Information
-
Patent Grant
-
6758906
-
Patent Number
6,758,906
-
Date Filed
Friday, April 20, 200123 years ago
-
Date Issued
Tuesday, July 6, 200420 years ago
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Inventors
-
Original Assignees
-
Examiners
Agents
- Venable LLP
- Kinberg; Robert
- Anderson; Chad C.
-
CPC
-
US Classifications
Field of Search
US
- 118 315
- 118 325
- 118 419
- 427 2071
- 427 356
- 156 578
- 239 290
- 239 5811
- 239 99
-
International Classifications
-
Abstract
Apparatus for the application of adhesive to one side of a running web of tipping paper for use in filter cigarete makers has a single source of adhesive or two or more sources containing identical or different adhesives, and one or more conduits leading from the source(s) to one or more nozzles which applies or apply one or more films of a single adhesive or of different adhesives to selected portions of the one side of the web. The rate of admission of adhesive(s) to the nozzle(s), including interruption and restarting of admission of adhesive(s), is regulated by one or more valves each having a body receiving a rotary valving element provided with one or more peripheral projections and/or recesses serving to regulate the rate of flow of adhesive toward the single nozzle or the respective nozzles. The rotary elements of two or more valves can constitute disc-shaped sections of a single rotor confined in a valve body common to all valves. The adhesive or at least one of two or more different adhesives being applied to the web can contain one or more taste- and/or odor- and or flammability influencing agents.
Description
The present application claims the priority of the commonly owned German patent application Serial No. 100 19 930.5 filed Apr. 20, 2000 and commonly owned European patent application Serial No. 01106122.3 filed Mar. 13, 2001. The disclosures of the above-referenced priority applications, as well as that of each US and foreign patent and patent application identified in the specification of the present application, is incorporated herein by reference.
BACKGROUND OF THE INVENTION
The invention relates to improvements in methods of and in apparatus for applying flowable adhesives to running strips or webs of paper or the like. More particularly, the invention relates to improvements in methods and in apparatus which can be resorted to with advantage in connection with the application of adhesive to running strips or webs (hereinafter called webs for short) of wrapping material of the type utilized in connection with the making and processing of smokers' products.
Examples of webs of wrapping material which must be provided with layers or films of special adhesive and/or with layers or films containing different types of adhesive are those which are employed for the assembly of filter rod sections with plain cigarettes to form filter cigarettes of unit length or multiple unit length. Wrapping material of such character is known as tipping paper and is utilized in machines known as filter cigarette makers or tipping machines. Examples of such machines are those known worldwise as MAX (distributed by the assignee of the present application). A MAX machine is designed to assemble successive groups of coaxial plain cigarettes and filter rod sections of unit length or multiple unit length, to connect the constituents of such groups with each other by resorting to so-called uniting bands (sections of a web of tipping paper one side of which carries a continuous or composite film of adhesive) which are convoluted around the filter rod sectons and the adjacent end portions of plain cigarettes, and to thereafter sever the groups to obtain filter cigarettes of unit length.
German patent No. 24 45 342 C2 discloses a machine which can change the quantity of adhesive being applied to successive still coherent uniting bands of tipping paper, i.e., prior to separation of successive foremost uniting bands from the leader of a running web of tipping paper. The quantity of adhesive per uniting band is changed by reducing or increasing the thickness of the film of applied adhesive and/or by changing the area(s) of the adhesive-coated portion(s) of each uniting band. The purpose of changing the quantity of adhesive per uniting band is to properly relate the quantity of applied adhesive to the permeability of the web of tipping paper and/or to properly relate the quantity of adhesive to the force with which certain portions of a uniting band must adhere to the filter mouthpiece, to the plain cigarette and/or both. The patented machine is further provided with means for intermittently interrupting the application of adhesive to the running web of tipping paper. This is accomplished by resorting to a rotary cam the RPM of which is related to the speed of the running web of tipping paper and which serves to alternatingly move the running web toward and away from the adhesive applying nozzle.
The patented apparatus exhibits certain drawbacks, especially as far as its versatility is concerned. For example, the patented apparatus applies adhesive to those portions of the running web which are not to be bonded to constituents of filter cigarettes. Furthermore, the patented apparatus increases the rate of application of adhesive immediately subsequent to each interruption of transfer of adhesive to the running web of tipping paper.
The aforementioned German patent also discloses a method of applying adhesive to a running web of tipping paper. The method involves the utilization of at least one nozzle with an orifice which discharges adhesive into contact with the running web of tipping paper. The method does not take into consideration the possibility of injury to a smoker, e.g., when the filter cigarette is smoked all the way to the end of the tobacco-containing part (i.e., to the end of the plain cigarette forming part of the filter cigarette). Combustion of the inner end of the tobacco-containing part of the filter cigarette can result in the development of flame (due to combustion of adhesive which forms part of the adhesive coat on the inner side of the convoluted uniting band), and such flame can cause injury to and can frighten the smoker. Moreover, once the tobacco-containing part of a filter cigarette is combusted close or very close to the end portion which is surrounded by the respective terminal portion of the convoluted uniting band, the glowing remaining part of the tobacco-containing portion is likely to fall to the floor or onto a chair or table or suit or dress with resulting damage to the carpet, to the piece of furniture or to the clothing and the danger of fire.
A further drawback of the patented method and apparatus is that the accuracy and predictability of the application of adhesive decrease when a tipping machine turns out filter cigarettes at a rate which can be achieved by resorting to modern high-speed tipping machines. This results in the making of a high percentage of rejects as well as in customer complaints.
OBJECTS OF THE INVENTION
An object of the present invention is to increase the predictability of the application of adhesive to running webs of wrapping material, such as tipping paper which is utilized in filter cigarette making machines.
Another object of our invention is to provide a method which can be resorted to for the application of adhesive to a running web of tipping paper or the like and which renders it possible to economize with the adhesive regardless of the complexity of the pattern which is formed by applied adhesive at one side of the web.
A further object of the invention is to provide a method which renders it possible to accurately select and/or alter the pattern formed by the adhesive at one side of a web of tipping paper or the like.
An additional object of the invention is to provide a method which renders it possible to impart to the adhesive desirable qualities and/or characteristics which were not known up to this time and/or which cannot be achieved by resorting to heretofore known and practiced methods.
Still another object of the instant invention is to provide a method which renders it possible to greatly reduce the likelihood of injury to and/or startling of the smoker as well as the possibility of damage to furniture, carpeting and/or clothing at the location(s) where filter cigarettes are being smoked in offices, at homes and/or elsewhere.
A further object of the invention is to provide a novel and improved apparatus for the application of flowable adhesive to running webs of paper or the like, such as webs of tipping paper for use in filter cigarette making machines.
Another object of the invention is to provide an apparatus which can properly and predictably apply one or more types of adhesive to a running web of tipping paper in modern high-speed tipping and/or analogous machines for the making of filter cigarettes, other smokers' products (such as cartons or packets for smokers' products), or products which are not classifiable as smokers' products but do employ or require the application of accurate patterns of adhesive substance(s) onto running webs of wrapping or other absorbent and/or foraminous material.
An additional object of the invention is to provide an apparatus which can be readily adjusted or converted for the application of one, two or more types of adhesive to different webs of adhesively bondable material and which can be installed in existing machines (such as the aforementioned tipping machines) for the making of various products including but not limited to smokers' products.
A further object of this invention is to provide rod-shaped smokers' products which are safer, more pleasing to the eye and tastier to smokers than heretofore known smokers' products.
Still another object of the invention is to provide an apparatus which exhibits the above-enumerated features and advantages, which can be utilized for the making of the aforementioned superior products, and which can be installed in or incorporated into existing mass-producing machines or productino lines.
A further object of the invention is to provide an apparatus which can interrupt and/or restart the application of adhesive to running webs of paper, tipping paper or the like with a degree of accuracy and predictability not achievable with presently known apparatus.
Another object of the invention is to provide an apparatus which can apply simple, complex or highly complex patterns of adhesive to a running web of paper or the like in such a way that the web is not induced or compelled to perform undesirable fluttering and/or other stray movements even when the application of adhesive takes place at a rate which is required in modern high-speed tipping machines or the like.
An additional object of the invention is to provide an apparatus which can repeatedly apply a pattern of adhesive films to one side of a running web of paper or the like in such a way that the quality of the pattern is higher than those achievable with conventional apparatus because the application of patterns is not affected by those irregularities of transport of the web which necessarily or normally develop in conventional apparatus.
A further object of the invention is to provide novel and improved filter cigarettes, filter cigars and analogous rod-shaped smokers' products.
An additional object of the invention is to provide novel and improved valves for use in the above outlined apparatus.
SUMMARY OF THE INVENTION
One of several features of the present invention resides in the provision of an apparatus which is designed to apply a flowable adhesive to selected portions of a running web of wrapping material, especially a wrapping material of the type utilized in connection with the making of smokers' products. A typical example of such wrapping material is so-called tipping paper which is to be subdivided into relatively short sections called uniting bands serving to connect filter mouthpieces with plain cigarettes in a filter cigarette making machine (also called tipping machine).
The improved apparatus comprises at least one source of adhesive (e.g., a tank), an applicator including at least one nozzle and having at least one adhesive-discharging orifice adjacent a course or path (hereinafter called course) for the running web, means (such as one or more groups of interconnected conduits, channels or the like) for connecting the at least one source with the applicator, and means for regulating (such regulation includes interrupting) the flow of adhesive in the connecting means. In accordance with an important and highly advantageous feature of the invention, the connecting means comprises at least one rotary valve, particularly a valve of the type wherein at least one rotor is confined in and can turn relative to a stator to thereby increase or reduce the rate of adhesive flow or to interrupt the flow of adhesive from the source to the applicator.
In a presently preferred embodiment, the at least one valve includes a valve body (stator) and at least one rotor which is disposed in and has a peripheral surface defining with the valve body at least one arcuate path for the flow of adhesive from the inlet to the outlet of the at least one valve. The peripheral surface of the rotor exhibits at least one irregularity or unevenness which is arranged to influence the flow of adhesive from the inlet to the outlet of the at least one valve. The at least one irregularity can include a recess (such as a groove) and/or at least one projection (e.g., a lobe or the like). The valve body can include or constitute a housing defining a chamber for the at least one rotor.
The applicator (such as the aforementioned nozzle) can be provided with at least one adhesive-storing chamber which communicates with the at least one orifice and can be resorted to for the purpose of regulating the quantity of adhesive being applied to unit lengths of one side of the running web. Similar or analogous results can be obtained by utilizing a nozzle with an orifice having a variable depth and/or capacity and/or another parameter which, if changed, influences the quantity of adhesive being applied to the web by the thus constructed applicator. In other words, the orifice(s) of the nozzle or nozzles is or are adjustable. For example, the arrangement can be such that the overall width of the applicator and/or of the orifice is adjustable.
The applicator, such as the nozzle(s) or a carrier for the nozzle(s), can be provided with an arcuate (such as convex) web-contacting surface which is adjacent a portion of the course for the web.
The apparatus is preferably provided with means (such as one or more pumps) which serves to adjust (such as vary) the pressure of adhesive in the connecting means.
The applicator can include or be constituted by a plurality of nozzles each having at least one adhesive-discharging orifice adjacent the course for the web. The connecting means of such apparatus can include discrete conduits each of which connects the at least one source (or a selected one of several sources) with a different nozzle. Such apparatus can further comprise means (such as two or more pumps) for individually selecting the pressure of adhesive in at least two conduits.
For example, the applicator can include at least two nozzles each having at least one adhesive-discharging orifice adjacent the course for the running web. The connecting means of such apparatus can include at least two conduits each of which connects the at least one source with a different nozzle, and the apparatus further comprises means (such as one or more pumps) for maintaining the pressure of adhesive in one of the at least two conduits at a value or level which at least approximates the pressure of adhesive in the other conduit. The connecting means can further include an additional conduit which communicates with the at least one source, and the at least two conduits have inlets which communicate with the additional conduit; the pressure maintaining means can include at least one pump which is disposed in the additional conduit upstream of the inlets of the at least two conduits.
At least a portion (e.g., at least one of several nozzles) of the applicator can be provided with a coat of a material which opposes (such as prevents) accumulations of adhesive on the applicator; this reduces the likelihood of clogging of one or more orifices and the resulting departure of actual rate of application of adhesive to one side of the running web from the desired or required rate of application.
In accordance with a desirable and advantageous additional feature of the invention, the apparatus further comprises means (such as one or more sensors and/or detectors) for monitoring at least one variable parameter of adhesive on the web. For example, the monitoring means can include means for ascertaining the quantity of adhesive being applied to the web. Alternatively, or in addition to such quantity-ascertaining monitoring means, the monitoring means can include means for generating signals denoting the monitored parameter(s) and the apparatus can further comprise means for adjusting the source and/or the applicator and/or the connecting means and/or the regulating means in response to (e.g., as a function of) such signals.
If the applicator comprises a plurality of nozzles each of which has at least one orifice, the regulating means of such apparatus can comprise a rotary valve for each nozzle. Each valve can include a valve body and a rotor which is disposed in and has a peripheral surface defining with the valve body at least one arcuate path for the flow of adhesive from the inlet to the outlet of the respective valve. The peripheral surface of each rotor can be provided with at least one irregularity (such as the aforementioned recess(es) and/or projection(s)) serving to influence the flow of adhesive from the inlet to the outlet of the respective valve. Each peripheral surface, or at least one of the peripheral surfaces, can be provided with two or more irregularities (e.g., with a projection and with a recess which at least partially surrounds the projection).
The improved apparatus or the machine which embodies or cooperates with such apparatus is provided with means for advancing the web along its course at a first speed, and with means for rotating (e.g., indexing) the rotor or rotors of the valve or valves forming part of the regulating means at a second speed. Such apparatus can further comprise means for synchronizing the operation of the advancing means with that of the rotating means.
The improved apparatus can comprise at least two sources of adhesive, e.g., a first source containing a first adhesive and a second source containing a different second adhesive. The applicator of such apparatus can comprise first and second nozzles each of which has at least one orifice adjacent the course for the web, and the connecting means of such apparatus can include at least one first conduit which serves to convey first adhesive from the respective (first) source to the first nozzle and at least one second conduit which serves to convey second adhesive from the respective (second) source to the second nozzle.
A presently preferred rotary valve of the improved apparatus can include a hollow stator and a rotor which is rotatable (such as indexible) in the stator about a predetermined axis. The stator and the rotor define an arcuate groove which is disposed in a plane normal to the predetermined axis and extending from the inlet to the outlet of the valve. The groove can extend along an arc which is close to but is less than 360°.
The applicator of the improved apparatus can comprise a plurality of nozzles each of which is provided with at least one orifice and each of which is adjacent a different portion of the course for the running web. The connecting means of such apparatus can include a plurality of conduits, at least one for each of the nozzles and each connecting the source or one of several sources with the respective nozzle. For example, the source of such apparatus can include a plurality of discrete sources of different adhesives, and the aforementioned conduits can include at least two conduits connecting one of the discrete sources with the respective nozzles. The regulating means of such apparatus can include a plurality of valves each of which has a hollow body and a rotor which is turnable in the respective body about a predetermined axis; the peripheral surface of each rotor defines with the respective valve body a path leading to one of the nozzles, and the valve bodies co-operate with the respective rotors to confine the adhesive to flow along the prescribed paths, namely to the respective nozzles.
The rotors of valves in the just discussed apparatus can constitute disc-shaped sections of a rotor which is common to all valves of the regulating means. Furthermore, the hollow bodies preferably form part of a stator which is common to and surrounds all of the disc-shaped sections, and the peripheral surface of each disc-shaped section can be provided with at least one irregularity which serves to influence the flow of adhesive within the respective hollow body.
At least one of the disc-shaped sections can cooperate with the respective hollow body to establish a seal against leakage of adhesive from the respective valve. Still further, the internal surfaces of such hollow bodies (i.e., the surfaces surrounding the respective rotors) can be provided with arcuate grooves for the flow of adhesive along the respective paths; the centers of curvature of such grooves are or can be disposed on the predetermined axis. Each such groove can extend along an arc which approximates but is less than 360°. As already mentioned hereinbefore, at least one of the nozzles can be provided with at least one adhesive-storing chamber which communicates with the respective orifice.
Another feature of the invention resides in the provision of a method of applying adhesive to selected portions of one side of a web, particularly a web of wrapping material for smokers' products. The improved method comprises the steps of advancing the web lengthwise along a predetermined course, placing first and second nozzles adjacent the one side of the web in a predetermined portion of the course, establishing first and second sources respectively containing first and second flowable adhesives, conveying adhesives from the first and second sources to the first and second nozzles, and utilizing the first and second nozzles for the application of first and second adhesives to the selected portions of one side of the web in the course.
The conveying step can include inducing the flow of first and second adhesives to the respective nozzles along discrete first and second paths, and the utilizing step can include intermittently applying at least one of the adhesives to the one side of the web in its course. Such step of intermittently applying at least one of the adhesives can include regulating the flow of the at least one adhesive by a rotary valve. The conveying step can be carried out by utilizing at least one pump for each of the first and second adhesives. In accordance with a presently preferred embodiment, the conveying step includes conveying the first and second adhesives along discrete first and second paths, and such method can further comprise the step of introducing into the adhesive at least one additive (such as a flavoring agent and/or a substance which prevents adhesive from adhering to parts of the valve(s) and/or nozzle(s)) in at least one of the first and second paths.
A further feature of our invention resides in the provision of a method of making rod-shaped smokers' products wherein a tubular envelope confines smokable material and at least a portion of the envelope consists of a section of a web of paper or the like one side of which is at least partially coated with at least one film of an adhesive. This method comprises the steps of advancing the web lengthwise along a predetermined course, establishing at least one source of flowable adhesive, positioning an orifice of at least one nozzle adjacent a portion of the course at one side of the advancing web, conveying adhesive along at least one path extending from the at least one source to the at least one nozzle, and regulating the flow of adhesive in the at least one path. This regulating step includes employing at least one rotary valve.
An additional feature of the invention resides in the provision of a method of making rod-shaped smokers' products wherein a tubular envelope confines a smokable material and at least a portion of the envelope consists of a section of a web one side of which is at least partially coated with at least one film of adhesive. This method comprises the steps of advancing the web lengthwise along a predetermined course, positioning the orifices of at least two nozzles adjacent a portion of the course at one side of the web, establishing at least two sources of flowable adhesive, and conveying flowable adhesive from each of the sources along a discrete path to a different one of the nozzles. Such method can further comprise the step of maintaining the adhesives in the paths at different pressures.
Another feature of the present invention resides in the provision of a novel article of manufacture which is a rod-shaped smokable product including a smokable filler and a tubular envelope consisting at least in part of a section of a web having one side at least partially coated with at least one film of adhesive. The at least one film contains at least two different types of adhesive.
At least one of the two or more different types of adhesive can consist, at least in part, of a combustion retarding material. Furthermore, at least one of the adhesives can contain a flavoring agent.
The filler can consist of cigarette tobacco and a filter mouthpiece, i.e., the smokable product can constitute a filter cigarette.
The aforementioned section of the web can constitute a convoluted uniting band of tipping paper which serves to attach one end portion of a plain cigarette to one end portion of a filter mouthpiece. Such band can include a first annular portion which is at least partially coated with adhesive containing at least one flavoring agent, and a second annular portion at least partially coated with adhesive consisting of or containing a combustion retarding material.
The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The improved apparatus itself, however, both as to its construction and the modes of assembling, installing and utilizing the same, together with numerous additional important and advantageous features and attributes thereof, will be best understood upon perusal of the following detailed description of certain presently preferred specific embodiments with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is a schematic exploded view of a web of tipping paper and of certain parts of one embodiment of an apparatus which can be utilized to apply films of adhesive to selected portions of one side of the web;
FIG. 2
is an enlarged partly schematic sectional view of certain details of the apparatus shown in the lower part of
FIG. 1
;
FIG. 3
is a schematic sectional view substantially as seen in the direction of arrows from the line III—III in FIG.
2
and shows one embodiment of a composite valve;
FIG. 4
is a similar schematic sectional view substantially as seen in the direction of arrows from the line IV—IV in
FIG. 2
;
FIG. 5
is a view similar to that of
FIG. 1
but showing certain details of a modified apparatus; and
FIG. 6
is an enlarged fragmentary perspective view of a structure somewhat similar to that shown in
FIGS. 3 and 4
but depicting a somewhat different valve and modified nozzles.
DESCRIPTION OF PREFERRED EMBODIMENTS
FIG. 1
shows a portion of an apparatus which embodies one form of the present invention. The character
10
denotes an elongated web of wrapping material, e.g., a web of paper which is to be subdivided into a series of successive so-called uniting bands
8
serving to be convoluted about abutting end portions of plain cigarettes
7
and filter rod sections
6
to form filter cigarettes of double unit length. For example, the web
10
can be subdivided into uniting bands
8
of the type formed in a so-called tipping (filter rod making) machine described and shown in commonly owned U.S. Pat. No. 5,135,008 granted Aug. 4, 1992 to Oesterling et al. for “METHOD OF AND APPARATUS FOR MAKING FILTER CIGARETTES”.
The patent to Oesterling et al. shows the details of a tipping machine wherein successive uniting bands (obtained upon repeated severing of the leader of a continuous web of tipping paper) are convoluted around successive filter rod sections of double unit length and the adjacent end portions of two plain cigarettes of unit length which flank the respective filter rod sections of double unit length and are coaxial therewith. The thus obtained filter cigarettes of double unit length are severed midway across the convoluted uniting bands of double unit length to yield pairs of filter cigarettes of unit length. One side of the running web of tipping paper is coated with a suitable adhesive prior to the subdividing step, and the web and/or the wrapper of each finished filter cigarette of unit length or double unit length is or can be perforated (if necessary) in order to increase the permeability of the tubular wrappers of such smokers' products.
The web
10
which is shown in the upper portion of
FIG. 1
is assumed to advance (stepwise or continuously) along a course or path wherein it advances in the direction indicated by arrow
9
. The illustrated web
10
is composed of a series of successive uniting bands
8
each of which is provided with two longitudinally extending parallel rows of perforations
11
. When the application of one or more suitable adhesives to selected areas of one side of each successive future uniting band
8
is completed, successive foremost uniting bands are separated from the leader of web
10
(i.e., from the immediately following uniting bands still forming part of the running web) along the transversely extending lines
13
. The thus separated foremost uniting band
8
(i.e., the uppermost band shown in
FIG. 1
) is thereupon convoluted around a group of three coaxial rod-shaped articles including a centrally located filter rod section (mouthpiece)
6
of double unit length and two plain cigarettes
7
of unit length. The thus obtained filter cigarette of double unit length is thereupon severed at
14
midway across the mouthpiece
6
and hence midway across the tubular envelope (converted uniting band
8
) to yield two filter cigarettes of unit length. The same procedure is thereupon repeated with the next-following (lower) uniting band
8
of the web
10
, and so forth. The just described steps of making successive pairs of filter cigarettes of unit length are fully described in and fully illustrated in
FIG. 2
of the aforementioned U.S. Pat. No. 5,135,008 to Oeasterling et al.
Each row of perforations
11
forms an annulus of holes around the circumference of the respective filter mouthpiece of unit length when the conversion of a uniting band
8
into the tubular wrapper of the filter mouthpiece
6
and the adjacent end portions of two plain cigarettes
7
of unit length is completed. The purpose of the perforations
11
is to permit entry of streamlets of cool atmospheric air into the filter mouthpiece (i.e., into one-half of a filter rod section
6
) when the smoker lights the exposed end of the tobacco-containing portion of the filter cigarette; this is believed to reduce the effect of nicotine and tar entering the mouth of the smoker by reducing the percentage of such substances in tobacco smoke. In
FIG. 1
, the perforations
11
are shown drawn to a greatly enlarged scale for the sake of clarity.
The characters
12
denote those areas of one side of each uniting band
8
which are to be coated with a suitable adhesive substance. Such areas do not include those which are provided with the perforations
11
and those which are to be severed (at
14
) to divide each convoluted web section
8
into two tubular wrappers simultaneously with subdivision of the respective filter mouthpiece
6
of double unit length into two filters of unit length. Absence of adhesive in the regions of perforations
11
is highly desirable because the adhesive could prevent or unpredictably and undesirably reduce the inflow of atmospheric air into the tubular filler of the filter mouthpiece forming part of the lighted filter cigarette.
Absence of adhesive at the free end (at
14
) of the filter mouthpiece of a finished filter cigarette of unit length at the very free end (at
14
) of the filter mouthpiece of a finished filter cigarette of unit length is just as desirable, for example, because the adhesive is less likely to come into contact with the lips of the smoker. In addition, the absence of adhesive at
14
ensures or increases the likelihood that the implement (the so-called cutoff) which is used to subdivide filter cigarettes of double unit length into filter cigarettes of unit length is less likely to be contaminated with adhesive. The same holds true for the regions
13
where the leader of the running web
10
is severed to yield discrete uniting bands
8
, i.e., the tool which is employed to carry out such severing work is less likely to be contaminated by adhesive.
Certain relevant component parts of an adhesive metering and applying apparatus which embodies one form of the present invention are shown schematically in the lower part of FIG.
1
. The apparatus comprises a holder or carrier
20
forming part of an applicator further including an array of five nozzles including a larger centrally located (twin) nozzle
121
and two pairs of identical or similar smaller nozzles
21
. The two pairs of nozzles
21
flank the nozzle
121
. Each nozzle
21
has an adhesive-discharging slit-shaped orifice
24
and an inlet
22
which receives adhesive from the discharge end of a conduit
23
(this conduit forms part of the means for connecting a single source
294
of adhesive with the applicator including the carrier
20
, the nozzles
21
and the nozzle
121
) and delivers adhesive to the orifice
24
by way of a recess or chamber
25
. The inlet
22
can constitute the discharge end of the respective conduit
23
of the connecting means.
The means for regulating the rate of flow (including terminating (interrupting) and restarting the flow) of adhesive from the single source
294
shown in
FIG. 1
(or from several sources
291
,
292
,
293
shown in
FIG. 5
) includes adjustable valves
26
in the connecting means including the conduits
23
and additional conduits
27
a
,
27
b
,
27
c
. The purpose of the chambers
25
is to regulate the rate of application of adhesive onto the respective portions of one side of the web
10
of tipping paper. In addition, or primarily, the chambers
25
serve to ensure that an adequate supply of adhesive is closely adjacent the loci of application of adhesive to the respective portions (strips) of one side of the web
10
.
The larger median nozzle
121
serves to supply adhesive to two median strips
5
at the one side of the web
10
; such strips flank the narrow uncoated portion
14
where the finished filter cigarette of double unit length is ultimately split into two filter cigarettes of unit length.
FIG. 1
shows that the valves
26
for the two outermost nozzles
21
receive adhesive at a first pressure P
1
, that the valves
26
for the nozzles
21
which immediately flank the centrally located nozzle
121
receive adhesive at a different second pressure P
2
, and that the valve
26
for the two sections or halves of the central or median nozzle
121
receives adhesive at a different third pressure P
3
. The adhesive which is supplied at the pressure P
1
is drawn from the single source
294
by a first adjustable pump
281
; a second adjustable pump
282
supplies adhesive from the source
294
to the nozzles
21
immediately flanking the nozzle
121
at the pressure P
2
; and a third adjustable pump
283
feeds adhesive, at the pressure P
3
, from the source
294
to the valve
26
for the median nozzle
121
.
The adjustments of the pumps
281
to
283
can be such that the pressure P
1
equals the pressure P
2
and that the pressure P
3
exceeds or is less than the pressure P
1
.
Since the two outermost nozzles
21
deliver adhesive to those (outermost) marginal portions
12
of one side of the running web
10
which are to adhere to the adjacent end portions of the wrappers of the two plain cigarettes
7
upon subdivision of the web into a series of discrete uniting bands
8
, such marginal portions
12
should normally receive relatively large quantities of adhesive. In other words, the marginal portions
12
of the web
10
should receive thicker or relatively thick layers or films of adhesive.
Furthermore, and since it is advisable to ensure a highly reliable delivery of preselected optimum quantities of adhesive to the web portions
12
which receive adhesive from the two outermost nozzles
21
, these two nozzles receive adhesive at an optimum pressure P
1
from the discrete pump
281
by way of conduits
27
a
leading to the respective outermost valves
26
. Such possibility of supplying adhesive to the two outermost valves
26
independently of the other valves is desirable and advantageous on the additional grounds that (a) this enables the improved apparatus to compensate for eventual departures of the finish of the outermost nozzles
21
from an optimum finish (i.e., to compensate for manufacturing tolerances of the outermost nozzles
21
), (b) this renders it possible to compensate for departures of the speed and/or guidance of the web
10
from optimum values, and/or (c) this renders it possible to compensate for eventual departures of absorbency of the web
10
or of certain strip-shaped portions of the web from a desirable optimum absorbency. In fact, it is also within the purview of the present invention to use discrete pumps (
281
) or other suitable sources of properly pressurized adhesive for each of the two outermost nozzles
21
.
The valves
26
at the inlets of those conduits
23
which supply adhesive from the pump
282
at the pressure P
2
are designed to supply adhesive intermittently, namely to those portions (shown at
52
in
FIG. 5
) of one side of the web
10
which alternate with the two rows of perforations
11
. Such intermittent application of adhesive via the two inner nozzles
21
is possible or can be carried out in a more reliable manner if the pressure P
2
of adhesive being supplied by the pump
282
is low, relatively low or very low. The pump
282
and the associated valves
26
cooperate to ensure that the pressure P
2
can be selected, varied and/or maintained in an optimum manner to ensure a highly predictable intermittent feeding of adhesive to the adjacent sections or strips of one side of the running web
10
by way of the nozzles
21
which are immediately adjacent the median nozzle
121
.
Those parts of the connecting means which include the conduits
27
a
and the respective conduits
23
cooperate with the pump
281
to supply adhesive to the two outermost nozzles
21
at the pressure P
1
which is best suited for application of adhesive to the areas
12
at one side of the running web
10
. The means for connecting the source
294
with the inner nozzles
21
includes two composite conduits each including a conduit
27
b
and the respective conduit
23
. The median nozzle
121
receives adhesive (at the pressure P
3
) from the source
294
by way of that part of the connecting means which includes the conduit
27
c
and the corresponding conduit
23
.
FIG. 2
shows one presently preferred form of that part (namely the regulating means) of the improved apparatus which includes the valves
26
. The five valves
26
have a common roller-shaped rotary valving element
32
which can be caused to turn by a suitable motor
126
in the cylindrical chamber of a stationary valve housing or valve body
30
(hereinafter called stator for short). The common axis of the stator
30
and valving element (rotor)
32
is shown at X—X. The clearances or gaps between the exterior of the rotor
32
and the internal surface of the stator
30
are filled with flowable adhesive. A cover
33
constitutes or forms part of a means for sealing the interior of the stator
30
(at one axial end of the rotor
32
) from the surrounding atmosphere. Such sealing means further comprises a resilient sealing ring
34
which is confined between the stator
30
and the cover
33
.
The composite valving system including the valves
27
further comprises a friction bearing
35
which ensures that the rotor
32
can be driven with a minimum of effort. In order to balance the forces or stresses which develop when the rotor
32
is caused to turn, the valving system of
FIG. 2
further comprises an antifriction ball bearing
36
.
Each of the five disc-shaped sections
461
to
465
of the rotor
32
forms part of one of the five valves
26
, and the corresponding annular sections of the stator
30
receive adhesive from the respective pumps
281
-
283
(not shown in
FIG. 2
) by way of the corresponding conduits
27
a
-
27
c.
FIG. 2
shows the rotor
32
in that angular position in which three of the five valves
26
can admit adhesive from the respective sources into the corresponding nozzles, namely to the conduits
23
leading to the two outermost nozzles
21
and to the conduit
23
leading to the central nozzle
121
. Thus, the apparatus embodying the structure of
FIG. 2
is set up to supply films of adhesive to the two marginal portions
12
at one side of the running web
10
and to the median portions
5
of such one side (namely to the two stretches flanking the narrow uncoated strip
14
and being flanked by the two rows of perforations
11
.
It is clear that the rotor
32
adequately seals the five annular sections of the chamber in the stator
30
from each other so that each of the five conduits
23
can receive adhesive only from the respective conduit
27
a
,
27
b
or
27
c.
The five sections
461
-
465
of the rotor
32
may but need not be made of one piece from a suitable metallic, plastic or other material. The sections
461
,
465
form part of the two outermost valves
26
, the section
463
forms part of the median valve
26
, and the sections
462
,
464
form part of the remaining two valves in the group of valves
26
shown in
FIGS. 1 and 2
. The peripheral surfaces of the rotor sections
461
-
465
are provided with male and/or female irregularities such as projections or lobes
37
which can be orbited about the axis X—X to positions of overlap or registry with the inlets of the respective conduits
23
(i.e., with the outlets of the respective valves
26
) so that such conduits are then sealed from the respective pumps
281
-
283
and conduits
27
a
-
27
c
. The female irregularities include recesses or depressions (such as grooves)
38
, each of which surrounds one of the projections
37
.
The heights of the projections
37
which are surrounded by recesses
38
are selected in such a way that their outermost portions (top lands) do not extend radially outwardly beyond the surfaces of the respective rotor sections
262
,
264
. Therefore, the conduits
23
leading to the two inner nozzles
21
of
FIG. 1
can receive only such adhesive which enters internal grooves
39
of the adjacent portions of the stator
30
. Each groove
39
can constitute a nearly circumferentially complete internal groove. One such groove
39
is shown in greater detail in
FIG. 3
; this groove defines an arcuate path extending along an arc of very close to but still less than 360°.
The sections
461
,
463
,
465
of the rotor
32
permit adhesive to flow from the respective conduits
27
a
,
27
c
,
27
a
into the associated conduits
23
during the entire revolution of the rotor
32
relative to the housing
30
except during the intervals of movement of their projections
37
along the inlets of the respective conduits
23
. The sections
462
,
464
of the rotor
32
cooperate with the stator
30
to permit entry of adhesive into the respective conduits
23
(i.e., onto the running web
10
) at a rate and to the extent necessary to apply adhesive to the web portions (at
52
in
FIG. 5
) between the respective rows of perforations
11
. To summarize, the valves
26
are designed and installed to enable the nozzles
21
,
121
to coat one side of the running web
10
save for the locations provided with the perforations
11
and the strips along the lines
13
and/or
14
shown in FIG.
1
.
FIG. 3
is a schematic sectional view as seen in the direction of arrows from the line III—III in FIG.
2
. That one of the two identical internal grooves
39
which is illustrated in
FIG. 3
extends along an arc of 360° minus the region where it communicates with the inlet of the respective conduit
23
leading to one of the two inner nozzles
21
. The rotor
32
turns in a clockwise direction as indicated by the arrow A. The section
462
of the the rotor
32
comprises three equidistant projections
37
each of which is surrounded by a recess
38
or by two discrete parts of a composite recess. The conduits
27
a
to
27
c
which are shown in
FIG. 3
can constitute, at least in part, bores or channels provided in the stator
30
and extending from the outlets of the respective pumps
281
-
283
to the chamber
31
of the stator
30
. The thus admitted adhesive gathers in the grooves
39
surrounding the rotor sections
462
,
464
and in those annular portions of the chamber
31
which surround the rotor sections
461
,
463
and
465
.
When the rotor
32
assumes the angular position which is shown in
FIG. 3
, it permits adhesive to flow around the rotor sections
461
,
463
,
465
and thence into the conduits
23
leading to the median nozzle
121
and to the two outermost nozzles
21
.
An annular sealing element
42
(e.g., an O-ring) which is shown in
FIG. 4
is provided to seal the eventual gap between the rotor
32
and a common head
44
accommodating and/or embodying the nozzles
21
and
121
. The adhesive flowing in the internal groove
39
of the stator
30
shown in
FIG. 3
gathers in the recesses
38
and flows from the recess
38
located at the 12 o'clock position of the rotor
32
into the conduit
23
leading to the respective outer nozzle
21
. The inlet
22
shown at the top of
FIG. 3
admits adhesive into a cavity
40
which serves to determine the quantity of adhesive entering the inlet
22
of the respective nozzle
21
. The inlet
22
admits the predetermined quantity of adhesive into the respective orifice
24
by way of the corresponding chamber
25
in the nozzle carrier
20
. The chamber
25
can also serve (or can serve in lieu of the cavity
40
) as a means for metering the quantity of adhesive which is to be discharged via the corresponding orrifice
24
.
A plate-like cover or lid
41
is provided to lie at least substantially flush against the head
44
. The peripheral surface
43
of the head
44
serves to guide successive increments of the running web
10
into the range of the orifices of the nozzles
21
and
121
. A pronounced or sharp tear-off edge is or can be provided immediately downstream of the nozzles
21
,
121
(as seen in the direction of the arrow
9
shown in
FIG. 1
, i.e., in the direction of advancement of the web), to separate successive uniting bands
8
from the leader of the running web.
The chambers
25
in the nozzle head
44
can be utilized to determine the quantity of adhesive being actually applied to successive increments of the corresponding strip-shaped portions of one (adhesive-receiving and bearing) side of the running web
10
. For example, the quantities of applied adhesive can be varied by utilizing a set of heads
44
each having cavities and/or chambers
25
of different sizes. The chambers
25
can serve to ensure that adequate quantities of adhesive can be stored to thus guarantee satisfactory distribution of adhesive along the full length of the carrier
20
, i.e., by way of all of the nozzles
21
and
121
.
FIG. 4
is a transverse sectional view of another portion of the carrier
20
, namely across the section
461
of the rotor
32
. The peripheral surface
45
of the rotor section
461
is provided with three projections
37
which serve to interrupt the admission of adhesive to the conduit
23
leading to the right-hand outermost nozzle
21
of FIG.
1
.
FIG. 5
illustrates a portion of a running web
10
of tipping paper and certain constituents of a modified adhesive applying apparatus which can be utilized to apply a predetermined pattern of adhesive films to one side of the web.
The hatched areas
51
denote those portions of one side of the web
10
which are coated with a first type (type
1
) of adhesive. These are the parts which adhere to and are convoluted around he inner end portions of plain cigarettes
7
(see
FIG. 1
) after the respective portion of the leader of the web
10
is converted into a uniting band which connects two coaxial plain cigarettes
7
with a filter mouthpiece
6
of double unit length.
A second type (type
2
) of adhesive is applied to the sections
52
of the web
2
shown in the upper portion of
FIG. 5
by the nozzles
21
which are immediately adjacent the median nozzle
121
. The sections
53
of that side of the web
10
which faces the observer of
FIG. 5
are coated (by the nozzle
121
) with films of a third type (type
3
) of adhesive; these films serve to bond the median portions of successive uniting bands
8
to the peripheral surfaces of filter mouthpieces
6
of double unit length.
Adhesive of the first type is drawn from a first source
291
by the pump
281
and is supplied (at the pressure P
1
) to the valves
26
serving to regulate the admission of adhesive to the two outermost nozzles
21
of the apparatus shown in FIG.
5
. The pump
282
draws adhesive of the second type from a sorce
292
and delivers such adhesive (at the pressure P
2
) to the valves
26
serving to regulate the flow of adhesive to the two inner nozzles
21
. Adhesive of the third type is drawn, by the pump
283
, from a third source
293
and is supplied (at the pressure P
3
) to the valve
26
which supplies adhesive to the median nozzle
121
.
The adhesive which is supplied by the source
291
can constitute a fire extinguishing and/or fire retarding and/or fire preventing substance. It will be recalled that such adhesive is supplied to the sections
51
of the running web
10
, i.e., to those portions of filter mouthpieces of filter cigarettes which are nearest to the lighted ends of such smokers' products.
The adhesive which is supplied by the source
292
(and is applied to the portions
52
of the illustrated surface of the running web
10
shown in
FIG. 5
) can constitute a standard adhesive (e.g., a hotmelt), and the adhesive furnished by the source
293
and supplied to the portions
53
of the web
10
can contain one or more flavoring agents, i.e., aromatic substances which are likely to be pleasant to the smoker and which are effective because they are applied to the mouthpieces of the finished filter cigarettes, i.e., to parts which enter the mouths of smokers of filter cigarettes.
The three sources
291
-
293
can be replaced with a single source (such as the source
294
shown in FIG.
1
). In order to impart to the apparatus of
FIG. 1
a versatility matching or approaching that of the apparatus shown in
FIG. 5
, the apparatus of
FIG. 1
is or can be provided with one or more injectors.
FIG. 1
shows a first injector
61
which supplies a combustion preventing or opposing agent (i.e., a substance corresponding to that contained in the adhesive confined in the source
291
shown in FIG.
5
). A second injector
62
can supply one or more desirable ingredients into the adhesive flowing in the conduits
27
b
serving to convey adhesive to the inner nozzles
21
, and a third injector
63
can be utilized to admit metered quantities of one or more flavoring agents into the conduit
27
c
servicing the valve
26
for the nozzle
121
.
Numerous other modifications of the improved methods and apparatus can involve various undertakings which contribute to compactness, versatility, lower cost and/or to other desirable characteristics of the ultimate products. For example, the improved apparatus can be modified for use in tipping machines of the character designed to produce filter cigarettes of unit length, i.e., to provide uniting bands large enough to combine plain cigarettes of unit length with filter mouthpieces of unit length.
Referring again to
FIGS. 1
to
4
, when one of the projections
37
and the concave surface
45
shown in
FIG. 3
advance past the inlet of the conduit
23
leading to the nozzle
21
shown in
FIG. 1
beneath the right-hand rows of perforations
11
, this conduit communicates with the pump
282
and the source
294
by way of the recess
38
at the 12 o'clock position of the disc
262
. On the other hand, when the disc
461
of the rotor
32
reaches the angular position of
FIG. 4
, the rightmost nozzle
21
is free to communicate with the respective conduit
27
a
by way of the right-hand groove
39
shown in
FIG. 2
, i.e., by way of the groove
39
shown in FIG.
4
.
One of numerous important advantages of the two improved apparatus shown in
FIGS. 1-4
and
5
is that they permit for highly accurate feeding of adhesive (from the single source
294
shown in
FIG. 1
or from the selected source or sources
291
-
293
shown in
FIG. 5
) into the nozzles provided in the respective carrier
20
. Moreover, the interruption of delivery of adhesive to one or more nozzles is not followed by the delivery of excessive quantities of adhesive upon renewed opening of the respective valve(s)
26
.
Another important advantage of the improved apparatus is that the rate of flow of adhesive into and from the nozzles
21
,
121
is uniform (i.e., steady) regardless of whether the flow of adhesive is restarted or is about to be interrupted. All this contributes to considerable savings in adhesive and to higher quality of the ultimate smokers' products because each selected section of one side of the web
10
is coated with an optimum quantity of adhesive which is supplied at the optimum pressure and from the appropriate source (provided that the improved apparatus employs two or more sources of adhesive—see the sources
291
-
293
shown in FIG.
5
).
The making of perforations
11
in the web
10
can be carried out prior to storing of the web in the form of a roll. Alternatively, the making of perforations
11
can take place while the web
10
is being advanced toward the carrier
20
for the nozzles
21
and
121
. The manner of making perforations in a running web of cigarette paper, tipping paper and the like is disclosed in numerous US patents many of which are owned by the assignee of the present application. Reference may be had, for example, to U.S. Pat. No. 5,060,668 granted Oct. 29, 1991 to Weinhold for “DEVICE FOR THE PRODUCTION OF AT LEAST TWO ADJACENT ROWS OF PERFORATIONS IN CIGARETTES AND/OR FILTER LINING PAPER OR FILTER WRAPPING PAPER”. Commonly owned U.S. Pat. No. 4,889,140 (granted Dec. 26, 1989 to Lorenzen et al. for “APPARATUS FOR MAKING PERFORATIONS IN ARTICLES OF THE TOBACCO PROCESSING INDUSTRY” discloses another apparatus which can provide a running web of wrapping material for rod-shaped smokers' products with several (e.g., four) rows of perforations. U.S. Pat. No. 4,121,595 (granted Oct. 24, 1978 to Heitmann et al. for “APPARATUS FOR INCREASING THE PERMEABILITY OF WRAPPING MATERIAL FOR ROD-SHAPED SMOKERS' PRODUCTS”) discloses an apparatus which can perforate a running web of cigarette paper or the like, or the tubular wrappers of rod-shaped smokers' products. At least some of the above-enumerated patents disclose apparatus which can provide the web
10
of
FIG. 1
or
5
with perforations
11
and/or with other suitable (e.g., other than round) perforations. As already explained hereinbefore, perforations which are provided in tubular envelopes of rod-shaped smokers' products are considered to be desirable and advantageous because they admit cool atmospheric air into the column of tobacco smoke flowing from the lighted end of a smokers' product into the smoker's mouth; this is believed to entail a reduction of the percentage of tar and nicotine in the tobacco smoke which actually reaches the smoker's mouth because such (cooled and less concentrated) substances are more likely to be intercepted by the filamentary or other filler of the filter mouthpiece.
Certain presently preferred methods of and apparatus for draping uniting bands around successive groups of coaxial plain cigarettes and filter mouthpieces are disclosed, for example, in commonly owned U.S. Pat. No. 4,825,882 granted May 2, 1989 to Hinz for “APPARATUS FOR ROLLING UNITING BANDS ABOUT GROUPS OF ROD-SHAPED ARTICLES”. Such or analogous apparatus can be utilized to convolute successive adhesive-coated uniting bands
8
around groups of coaxial rod-shaped articles (such as the articles
7
,
6
,
7
shown in
FIG. 1
) upon separation of successive adhesive-coated bands from the leader of the web
10
.
The valves
26
of the type shown in
FIGS. 1-4
(the valves in the apparatus of
FIG. 5
are or can be identical with those shown in
FIGS. 1-4
) together constitute a novel composite valve which has been found to be highly satisfactory for use in a filter cigarette maker or an analogous machine, and more specifically in that part or aggregate or module of a filter cigarette maker or the like which is to regulate the flow of a given type of adhesive or of two or more different types of adhesive to one side or surface of a running web of wrapping material or any other material which web need not or should not have one of its sides fully coated with one or more adhesives and/or which is to be provided with a relatively simple and/or a complex or highly complex pattern of adhesive films.
The illustrated and/or analogous recesses (such as
38
) and/or projections (
37
) exhibit the advantage that they can be provided in the rotor
32
in a time-saving manner as well as by resorting to relatively simple and readily available tools, groups of tools or machines. Such and/or analogous recesses and projections can be formed in, at and/or on the peripheral surfaces of discrete discs (
461
-
465
) which are thereupon assembled into a one-piece rotor (
32
), or in a one-piece rotor wherein the discs are neighboring parts of a converted one-piece block of a suitable material. An additional advantage of the projections
37
(or analogous projections) and/or of the recesses
38
(and/or analogous recesses) is that they can be readily formed and finished with a requisite degree of precision by resorting to available machinery.
An additional important advantage of the improved composite valve including the rotor
32
and the valve housing or stator
30
therefor is that such flow regulating means occupies a relatively small amount of space which is always at a premium in a modern filter cigarette maker. Moreover, the parts
37
,
38
can be readily provided with a degree of finish which ensures that the wear upon such parts is negligible or minimal, even after long periods of extensive use, especially since at least some types of adhesive can serve as a substance which lubricates the external surface of the rotor
32
and/or the internal surface of the stator
30
.
The just discussed composite valve (i.e., the adhesive flow regulating means of the improved apparatus) is surprisingly simple in spite of its versatility and ability to provide the web
10
with a relatively simple as well as a complex or highly complex pattern of adhesive films. Thus, all that is actually necessary is to provide the peripheral surface of the rotor
32
with a more or less complex pattern of projections (
37
) and/or recesses (
38
) and to ensure that such unevennesses or irregularities are properly distributed at the periphery of the rotor. Identical, similar, slightly different and/or pronouncedly different patterns of unevennesses or irregularities
37
,
38
and/or the like can be provided on neighboring and/or spaced-apart discs (
461
-
465
) of the rotor
32
shown in
FIG. 5
, depending upon the desired distribution of adhesive film patterns (
12
,
13
,
14
and/or the like) on successive uniting bands
8
to be yielded by the properly coated web
10
downstream of the carrier
20
.
At least one of the discs
461
-
465
shown in
FIGS. 2
to
4
can serve at least one additional purpose, for example, that of a sealing element which prevents adhesives of different types (see the sources
291
-
293
shown in
FIG. 5
) from mixing with each other. In addition, such at least one disc (or at least one other disc) can prevent adhesive streams which are to be maintained at different pressures (such as P
1
, P
2
and P
3
) at least during certain stages of their flow from the pressurizing means (
281
-
283
) to those portions of their respective paths wherein it is no longer necessary to maintain the contents of discrete adhesive streams at different pressures. The surface(s) of at least that disc or those discs of the rotor
32
and the adjacent portion(s) of the internal surface of the valve body or stator
30
are preferably smooth surfaces; this simplifies and enhances the sealing action and reduces the likelihood of extensive wear. The seals between neighboring discs (
461
-
465
) of the rotor
32
and the adjacent portions of the internal surface of the stator
30
can be established by providing the discs with circumferentially complete rings (not specifically shown due to the relatively small scale of
FIG. 2
) which are received in the stator
30
with minimal clearance or play. The provision of bearing means
35
and/or
36
also contributes to a reduction of leakage of adhesive between neighboring valves
26
of the composite valve including the rotor
32
and the stator
30
.
The adhesive which is stored in the single source
294
or the adhesives stored in the sources
291
-
293
can be of the commercially available type, e.g., one or more so-called cold glues or one or more so-called hot melts. Special qualities can be imparted by resorting to one or more injectors (such as those shown at
61
-
63
in FIG.
1
). It goes without saying that one or more such injectors can also be installed in the apparatus of FIG.
5
and/or that the stream of adhesive flowing in the conduit
27
a
and/or
27
b
and/or
27
c
can receive additives from two or more injectors.
FIG. 1
shows, by way of example, an injector
63
a
which is set up to introduce at least one additive into the conduit
27
c
in addition to that additive or those additives which can be introduced by the injector
63
.
It is also possible to employ one or more injectors (one shown at
64
) in at least one conduit
23
in addition to or in lieu of one or more injectors
61
-
63
and
63
a
in the conduit
27
a
and/or
27
b
and/or
27
c.
By way of example, the injector
61
of
FIG. 1
can be utilized to admit requisite quantities of an aroma infuencing substance (flavoring agent), e.g., a substance which can be extracted or otherwise obtained from certain types of tobacco. Alternatively, or in addition to such aroma influencing substances which are derivable from tobacco, it is possible to resort to natural or synthetic aroma influencing ingredients (flavoring agents) such as vanilla, cocoa and/or others. These aroma influencing substances are or can be admitted to adhesive which is to cover the central sections
5
of the web
10
, i.e., which is to be contained in that portion of a convoluted uniting band
8
that is to enter the mouth of the smoker, i.e., the end portion remotest from the plain cigarette
7
.
At least one section of one side of each uniting band
8
can be coated (at least in part) with an adhesive containing a suitable combustion- or flame-retarding or preventing substance, such as diammonium hydrogen phosphate. Such substance can be admitted via injector
61
of
FIG. 1
to be confined in the adhesive coating the sections
12
of the web
10
shown in FIG.
1
. Other combustion- or flame-retarding substances which can be applied in addition to or in lieu of diammonium hydrogen phosphate include melamine and dipentaerythrite.
The composite valve including the stator
30
and the rotor
32
can be provided with means for reliably sealing the adhesive supplied by the nozzle
121
from adhesive supplied by the two outer nozzles
21
in order to ensure that the adhesive (from the source
291
shown in
FIG. 5
) containing a combustion or flame retardant is not mixed with adhesive from the source
293
if the adhesive from the source
293
contains an aroma-influencing ingredient.
The provision of one or more grooves
39
in the internal surface of the valve body or stator
30
(in a plane which is normal to the axis X—X of the rotor
32
) constitutes a simple but reliable solution of the problem of properly sealing regions for reception of adhesives at different pressures (such as P
1
and P
3
or P
1
and P
2
or P
2
and P
3
) from each other. In addition, the provision of such grooves constitutes a simple and inexpensive but reliable solution of the problem of establishing small, sharply defined (if necessary) and adequately separated patterns in close or immediate proximity to each other.
An advantage of the chambers
25
is that they render it possible to transfer metered quantities of adhesive from the respective nozzles
21
,
121
onto the adjacent portions of the running web
10
. A chamber
25
can be provided for each of the nozzles
21
,
121
or for one or more selected nozzles. The nozzles
21
,
121
are preferably slotted (see the slit-shaped orifices
24
).
If the capacities and/or the depths of the chambers
25
are adapted to conform to the quantities of adhesive to be applied by the respective nozzles
21
or
121
, it is possible to vary or alter the quantities of adhesive to be applied to selected portions of one side of the running web
10
in a simple but highly reliable manner. It is particularly desirable to provide means for adjusting or conforming to a predetermined width the width(s) of the chamber(s)
25
and/or orifice(s)
24
of one or more nozzles
21
,
121
. This also permits for rapid adjustment of each of the thus adjustable nozzles to ensure that an optimum distribution, configuration and/or dimensioning of the respective film(s) or layer(s) of adhesive can be arrived at with little loss in time, i.e., without much experimentation and with minimal losses in web material and/or adhesive.
In accordance with a presently preferred embodiment, the carrier
20
and its nozzles
21
,
121
can be made of stainless steel and each of the orifices
24
can have a length of between 6 and 12 mm and a width of 0.15 mm. Reference may be had, for example, to the German patent application No. 44 37 764 of Krappweis (published Apr. 25, 1996) and to the corresponding U.S. Pat. No. 5,769,947 granted Jun. 23, 1998 for “APPLICATOR FOR ADHESIVE AND CORRESPONDING NOZZLE PLATE”. This patent discloses an apparatus employing a so-called nozzle plate provided with rows of circular orifices receiving adhesive from so-called glue valves the details of which are not shown and/or described. The patentee states that the glue valves can be electrically controlled in accordance with a high switching frequency.
It is often advisable to furnish the apparatus of the present invention with a set of carriers
20
each of which comprises one or more nozzles different from the nozzle(s) of the other carrier(s). A relatively small number of spare carriers
20
normally suffices to greatly enhance the versatility of the improved apparatus.
The convex external surface
43
of the head
44
of the carrier
20
(downstream of the stator
30
, as seen in the direction (arrow
9
) of advancement of the web
10
) renders it possible to ensure that the web
10
can advance steadily (i.e., uninterruptedly or steadily at an optimum speed) which contributes to desirable predictability of the shapes and thicknesses of various films of adhesive being applied by te nozzles
21
and
121
. The web
10
advances at an acute angle toward the severing or separating station (not shown) where it is folded and severed along successive lines
13
at which successive (adhesive-coated) uniting bands are separated from the leader of the next-following portion of the running web. The curvature of the peripheral surface
43
is selected to conform to the desired distance between successive lines
13
; this renders it possible to ensure a steady and highly predictable advancement of successive (still coherent) uniting bands
8
toward the uniting band separating station.
The pumps
281
-
283
are preferably adjustable. This is desirable on the ground that adjustments of the pressure P
1
, P
2
and/or P
3
enable the person(s) in charge or an automatic control system to accurately select and/or vary the quantity of adhesive being applied per unit length of the running web
10
.
The pressure of adhesive in each of the conduits
27
a
-
27
c
and/or in one or more selected conduits
23
can be varied by the pumps
281
-
283
and/or by varying the widths (cross-sectional areas) of the conduits
27
a
,
27
b
and/or
27
c
. Such and/or other suitable undertakings render it possible to accurately conform the quantity of flowing adhesive to the speed of forward movement of the web
10
in a filter cigarette making or other machine, i.e., to the momentary output of such machine.
In a conventional filter cigarette making machine, namely in a machine wherein the application of adhesive patterns to one side of a running web of wrapping or tipping paper is effected by the peripheral surfaces of adhesive-applying rollers, the quantity of adhesive being transferred to the running web decreases proportionally with the operating speed (output) of the machine. On the other hand, a presently preferred method of this invention (which is being practiced with an apparatus employing nozzles) provides for increases of the pressure of adhesive in synchronism with increasing output of machine. The characteristic curve of such mode of operation is individually ascertainable and selectable for each of the various adhesives (such as those supplied by the sources
291
-
293
). If the pressure (P
1
, P
2
or P
3
) of the adhesive is increased in accordance with a specific characteristic curve, one can achieve an unchanging rate of adhesive application within the entire operating (RPM) range of the machine which embodies the apparatus of the present invention.
The improved apparatus can embody or can cooperate with means for effecting an intermittent (interruptable) delivery of adhesive; this is desirable and advantageous because such mode of admission of adhesive facilitates or brings about an automatic cleaning of (expulsion of contaminants from) the nozzles, especially of the nozzles which (as already described hereinbefore with reference to the nozzles
21
,
121
) are nozzles provided with elongated slot-shaped orifices.
Contaminations of the nozzles are likely to take place because the conveyed adhesive often entrains contaminants and/or due to the development of nucleation at the locations of pronounced wettability (hydrophylia). This results in the development in the adhesive flow of often pronounced tracks which contain a reduced quantity of adhesive or are even devoid of any adhesive. Tracks of such character can be eliminated by the intermittent application of elevated pressure(s), e.g., elevated pressures which can be caused to arise, e.g., in response to short-lasting sporadic or repeated closing and opening of a valve or the like. For example, the irregularities
37
,
38
and/or analogous irregularities of the discs
461
-
465
can act as valving elements which repeatedly seal and expose the inlets of the conduits
23
with attendant intensive cleaning or unclogging of the paths for the flow of adhesive from the pumps
281
-
283
to the valves
21
,
121
.
An important advantage of the feature that those portions of the one side of the web
10
which are adjacent the separation lines
13
between successive uniting bands
8
being obtained in response to repeated severing of the leader of the web
2
are uncoated is that the tool which is being employed to separate successive uniting bands from the remainder of the web is invariably highly unlikely to be contaminated by adhesive. This reduces the number of down times of the machine which utilizes or cooperates with or embodies the improved apparatus. The just discussed feature (i.e., absence of adhesive along the lines
13
) is of added importance because the severing tool or tools is or are less likely to be or cannot be contaminated with adhesive during standstills of the apparatus, e.g., if the tool or tools is or are in contact with the web
10
while the web is idle. Intervals of idleness of the web
10
can alternate with intervals of advancement at regular intervals in certain types of tipping machines.
The web
10
is also likely to be brought to a standstill, e.g., during replacement of an expired reel of such web with a fresh reel. Thus, those filter cigarettes which contain portions of a web coming from an expiring reel and portions of a fresh reel (i.e., coming from a web which is being drawn off a fresh reel and is spliced to the trailing end of the preceding web) are expelled from the tipping machine. Such stoppages of the improved apparatus can take place in response to the generation of signals by one or more detectors serving to track the splice between the web coming from an expiring reel and the web coming from a fresh reel. Filter cigarettes embodying portions of spliced-together expiring and fresh webs of tipping paper are normally expelled from the tipping machine by pneumatic ejector means.
An advantage of the feature which is shown in
FIGS. 1 and 5
, namely that the output of a pump (such as
281
or
282
) is connected with several nozzles (such as the two outer nozzles
21
by way of the conduits
27
a
and the respective conduits
23
and the two inner nozzles
21
by way of the conduits
27
b
and the respective conduits
23
) is that this renders it possible to avoid the development of excessive pressure peaks during closing of the respective valves
26
and/or during interruption of delivery of adhesive (e.g., in response to stoppage of the pump
281
and/or
282
or in response to closing of a valve (not shown) between the source
291
or
292
and the respective pump
281
or
282
. The just discussed feature renders it possible to divide the pressure peaks between pairs of valves
26
, i.e., to reduce such pressure peaks in half.
In accordance with a further important feature of the present invention, at least certain portions of the nozzles
21
and/or
121
are provided with coats or films of a substance which prevents the adhesive from clinging to portions of surfaces or to entire surfaces of such valves. Such prevention of accumulations of caked-on adhesive upon the surfaces of the nozzles reduces the likelihood of undesirable changes in the thicknesses of adhesive films which are being applied to selected portions or sections (such as
51
and/or
53
) of the running web
10
. For example, the aforementioned adhesive repellent can be applied to the surfaces bounding the orifices
24
and/or the chambers
25
of the nozzles
21
and/or parts which are made of metallic sheet material or the like. Such application is particularly important for those surfaces which bound narrow slit-shaped orifices and like passages where a relatively minor change in the width of the path for the flow of adhesive can result in a highly pronounced change of the rate of adhesive flow, i.e., in the thicknesses of adhesive films being applied to the running web.
The effectiveness of repellent which has been applied to surfaces bounding the orifices and/or other narrow or relatively narrow passages in the nozzles
21
and/or
121
can be monitored by resorting to one or more suitable detectors which monitors or monitor the thicknesses of the still wet adhesive films on the running web
10
and/or the thicknesses of dried adhesive films on or in the corresponding portions of tubular wrappers of finished filter cigarettes or the like. The detector or detectors can constitute optical or capacitive sensor(s). Acceptable capacitive sensors are disclosed, for example, in German patent No. 39 09 990; such sensors are designed to furnish signals denoting the sufficiency or lack of sufficiency of adhesive which is being applied to sheets of paper or the like. Signals which are being generated by the patented capacitive sensor are transmitted to an evaluating circuit which, in turn, transmits signals that are utilized to arrest the machine if the thickness of the monitored adhesive film is insufficient or excessive. A capacitive sensor of the type disclosed in the aforementioned German patent is installed adjacent the uncoated side of a running paper strip to ascertain the quantity of moisture in the applied adhesive layer and to thus indirectly indicate the thickness of such layer.
Another suitable system which is capable of ascertaining the adequacy and lack of adequacy (i.e., excessiveness and/or insufficiency) of an adhesive film or layer is disclosed in European patent 0 300 734 A2. This publication discloses an optical sensor which ascertains the intensity of radiation being reflected by the adhesive film on a running substrate of paper or the like. The intensity and/or other characteristics of a beam of radiation which is reflected by a web of paper or an analogous substrate is different from that which is reflected by a film of adhesive; furthermore, the intensity of radiation being deflected by a film of adhesive varies in dependency upon the thickness of the adhesive film.
It is within the purview of the present invention to equip or associate the improved apparatus with an optical and/or capacitive and/or other suitable sensor
60
′ (see
FIG. 5
) which constitutes a monitoring means and transmits signals to an evaluating unit
61
′ (e.g., an electronic circuit); the latter transmits (when necessary) signals to a prime mover
62
′ of a filter cigarette making machine, and such prime mover is brought to a halt if the thickness of applied adhesive layer(s) is excessive or insufficient. Alternatively or in addition to such regulation of the prime mover
62
′, the evaluating circuit
61
′ can transmit signals to an adjustable arrangement
63
′ which regulates the operation of the pumps
281
-
283
and/or of a variable-speed motor
64
′ serving to advance the web
10
(in the direction of arrow
9
) at a selected one of a finite or infinite number of different speeds.
The sensor
60
′ can constitute a laser-operated distance sensor which is or which can be installed adjacent the nozzles
21
,
121
. This sensor can distinguish between the thickness of an uncoated portion of the web
10
and the thickness of a web portion which carries a film of adhesive. Alternatively, the sensor
60
′ can monitor the distance of the web
10
from a reference point; such distance increases or decreases when the pumps
281
-
283
are started and at least one of the valves
26
is open, i.e., when the adhesive issuing from one or more nozzles
21
,
121
begins to impinge upon the running web. Furthermore, the aforementioned distance changes also when the quantity of adhesive issuing from the nozzle(s)
21
and/or
121
changes, i.e., the sensor
60
′ can indirectly monitor the thickness(es) of the adhesive film(s) being applied to the running web by one or more nozzles of the array of nozzles
21
,
121
shown in FIG.
5
.
The controls including the parts
60
′ to
64
′ shown in
FIG. 5
are designed to adjust (at
63
′) the pressure of adhesive being applied by the pumps
281
-
283
and/or (at
64
′) the speed of lengthwise movement of the web
10
in the direction indicated by the arrow
9
. It is also possible to employ adjustable nozzles
21
and/or
121
and to monitor the thicknesses of adhesive films or layers on the web
10
for the purpose of adjusting such valve(s) when the monitored thickness of the adhesive film(s) departs from a range of acceptable thicknesses. The corresponding output of the evaluating circuit
61
′ is shown at
65
′. Still further, the evaluating circuit
61
′ can have an output (
66
′) which transmits signals to adjustable flow restrictor means (one shown schematically at
67
′) which can regulate the effective cross-sectional area(s) of conduit(s)
27
a
,
27
b
,
27
c
and/or
23
and hence the rate of flow of adhesive to te nozzle(s)
21
,
121
, i.e., the thickness(es) of adhesive film(s) being applied to the web
10
.
The evaluating circuit
61
′ can also serve to regulate the rotational speed of the rotor
32
forming part of the composite valve further including the body or stator
30
. The corresponding output of the circuit
61
′ is shown at
68
′; the signals being transmitted by the output
68
′ control the RPM of the motor
126
.
As already mentioned hereinbefore, the rotor
32
can be provided with one or more irregularities (such as
37
and/or
38
) per disc (
461
-
465
). For example, if one of these discs is provided with a single irregularity, the RPM of the rotor
32
can be selected in such a way that the application of adhesive to one of the uniting bands
8
is completed in response to one complete revolution of the rotor. Thus, if the number of irregularities per disc exceeds one, the improved apparatus is set up to complete the application of adhesive to two or more successive uniting bands
8
during each revolution of the rotor
32
.
The accuracy of the outlines of adhesive films being applied to one side of the web
10
is higher if the number of irregularities on the rotor
32
is lower. The interruption of application of adhesive (such as at
13
on the web
10
shown in
FIG. 1
) is simpler and more reliable if the distances between successively applied discrete adhesive films are greater. This can be achieved by prolonging he intervals of standstill of the rotor
32
; however, such prolonging necessitates a rotation at high speed when the rotor is in motion. The selection of optimum circumstances for the operation of controls for the improved apparatus will be readily comprehended by those skilled in such field of endeavor upon perusal of the preceding passages of this disclosure.
It is often preferred to select the characteristics of the rotor
32
in such a way that at least one of its discs
461
-
465
carries four irregularities (such as
37
and/or
38
). The motor
126
(
FIG. 1
) for the rotor
32
can be operated in synchronism with the variable-speed motor
64
′ which advances the web
10
in the direction of arrow
9
. Such arrangement, combined with the provision of at least four irregularities on at least one of the discs
461
-
465
, renders it possible to accelerate, to slow down, to arrest and/or to start the filter cigarette maker without affecting (or without unduly affecting) the quality of filter cigarettes which are being turned out while the maker is driven at a speed other than its normal opeating speed.
A feature of the improved method resides in the provision of steps of employing at least two different types of adhesive and utilizing an applicator which is constructed and assembled to apply different adhesives to different sections or portions of each uniting band of the running web, i.e., to each of a succession of web sections which constitute discrete uniting bands upon separation from the leader of the web.
The novel method renders it possible to apply different types of adhesive; this term is intended to encompass identical adhesives exhibiting different characterisics, e.g., as a result of injection of additives at
61
,
62
and/or
63
as described with reference to and as shown in FIG.
5
. Thus, the sections
53
of the running web
10
shown in
FIG. 5
can be coated with an adhesive which contains materials and/or substances affecting the taste and/or aroma of the part of the mouthpiece coming into actual contact with the lips of the smoker. On the other hand, the sections
51
of the web
10
shown in
FIG. 5
(i.e., the sections which bond the mouthpieces to the respective plain cigarettes
7
) can contain a flame or combustion retarding or preventing substance or a higher percentage of such substance than the adhesive films applied to other portion(s) of each uniting band.
A glow-preventing substance in the adhesive coating the sectons
51
of the web
10
shown in
FIG. 5
can serve to prevent or to reduce the likelihood of development of glowing remnant of the inner end of the tobacco-containing portion of a filter cigarette; such embers could fall onto the carpet, onto a piece of furniture or onto the doting of the smoker and could start a fire or other damage.
It is also within the purview of our invention to rely upon a method which can be practiced with advantage by resorting to the apparatus of
FIG. 1
or
5
, namely to an apparatus wherein the number of sources of adhesive is less or much less than the number of nozzles. Thus, and referring again to
FIG. 1
, a single source
294
of adhesive can supply adhesive to three pumps (
281
-
283
), and these three pumps can meet the requirements of five nozzles (
21
,
121
). If it should become necessary to change the composition and/or other characteristics of the adhesive being conveyed from the pumps
281
-
283
to the respective valves
26
, one resorts to the injector
61
and/or
62
and/or
63
in order to introduce into the respective adhesive stream one or more additives which influence the existing characteristics or impart one or more characteristics to the adhesive which is to be discharged by the nozzle
121
and/or by one or more nozzles
21
. It will be seen that the injectors
61
-
63
are installed ahead (upstream) of the valves
26
. However, it is equaly possible to install the injector
61
and/or
62
and/or
63
even closer to the respective nozzle or nozzles e.g., if the additive is likely to evaporate (at least in part) prior to reaching the running web
10
.
Another important advantage of the injectors is that they render it possible to reduce the overall dimensions of the improved adhesive applying apparatus. Thus, it suffices to resort to a single source (
294
) of adhesive rather than to two, three (see
FIG. 5
) or even more sources each of which can constitute a rather bulky vessel, tank or the like.
Compactness of a filter cigarette maker is a highly desirable and advantageous characteristic because, as a rule, such machine is but one of a series or group of machines which together form a production line normally employing a tobacco processing assembly arranged to supply properly prepared tobacco particles to a cigarette maker. The cigarette maker converts the tobacco particles into a continuous rod-like filler which is draped into a web of cigarette paper to yield a continuous cigarete rod. The rod is subdivided into a series of plain cigarettes of unit length or multiple unit length which are fed into a filter cigarette maker. The latter further receives filter rod sections of unit length or multiple unit length from a filter rod making machine which, in many respects, resembles a cigarette maker, e.g., a cigarette maker known as GARANT and distributed by the assignee of the present application. The filter rod maker can be of the type disclosed, for example, in U.S. Pat. No. 4,412,505 granted Nov. 1, 1983 to Hüsler et al. for “APPARATUS FOR APPLYING ATOMIZED LIQUID TO A RUNNING LAYER OF FILAMENTARY MATERIAL OR THE LIKE”. A GARANT-type cigarette maker is disclosed, for example, in U.S. Pat. No. 4,281,670 granted Aug. 4, 1981 to Heitmann et al. for “APPARATUS FOR INCREASING THE PERMEABILITY OF WRAPPING MATERIAL FOR RODSHAPED SMOKERS' PRODUCTS”. As concerns the filter cigarette maker which can be utilized in the aforedescribed productino line, reference may be had, for example, to the aforementioned U.S. Pat. No. 5,135,008 to Oesterling et al.
Finished filter cigarettes are supplied to a packing machine which, in turn, delivers soft cigarette packs, so-called hinged-lid packs or other types of packs to a machine wherein the packs are confined in transparent envelopes prior to being admitted into a carton filling machine.
The invention also relates to a web of wrapping material which can be utilized with particular advantage for the making of filter cigarettes and carries one or more strips or otherwise configurated continuous or discontinuous layers or films of adhesive. The adhesive is a flame retardant or a flame preventing or extinguishing substance or contains metered quantities of such substance.
Another novel feature of the improved web is that it carries or can carry one or more films containing several types of adhesive, e.g., an adhesive which is a flame retardant, at least one adhesive which imparts a particular taste or flavor, and so forth.
Still further, the invention encompasses rod-shaped smokers' products (such as filter cigarettes, cigars or cigarillos) which exhibit at least one, at least two or more than two (such as all) of the aforediscussed novel characteristics. The adhesive which can be applied to the web of tipping paper or the like can be of a pasty or any other consistency which is suitable for the application to a running web by resorting to the methods and/or to the apparatus of the present invention.
The exact viscosity of the adhesive in the sources
291
-
294
will depend upon the nature of the web and/or upon the characteristics of the devices (such as pumps, valves, nozzles and the like) which are utilized to prepare, to store, to convey and to apply the adhesive to a running web of tipping paper or the like.
The only chamber
225
which is shown in
FIG. 6
is different from those shown at
25
in
FIGS. 1
,
3
and
4
, namely the chamber
225
is higher and overlies the radially inner part of the respective orifice
24
. The width of each orifice
24
is between 6 and 12 mm, and its depth is or approximates 0.15 mm. The stator
30
is made of stainless steel and its peripheral surface
43
guides the running web
10
. The surface
43
is coated with a substance which prevents adherence of adhesive to the stator
30
.
FIG. 6
further shows a control bore
47
about 2 mm deep and about 0.6 mm wide. This bore allows for more accurate regulation of the delivery of adhesive to the orifices
24
. Thus, and since the cross-sectional area of the bore
47
is relatively small, it permits for more accurate regulation of the flow of adhesive to the nozzles
21
and
121
. The reference character
48
denotes the tear-off edge which is located immediately downstream of the nozzles
21
,
121
.
Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic and specific aspects of the above outlined contribution to the art of making filter cigarettes and the like and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the appended claims.
Claims
- 1. Apparatus for applying a flowable adhesive to selected portions of a running web of wrapping material for smokers' products, comprising:at least one source of adhesive; an applicator having at least one adhesive-discharging orifice adjacent a course for the running web; means for connecting said at least one source with said applicator; and means for regulating—including interrupting—the flow of adhesive in said connecting means, comprising at least one rotary valve, wherein said at least one rotary valve has a peripheral surface and a plurality of rotary section having at least one irregularity on the peripheral surface.
- 2. The apparatus of claim 1, wherein said at least one valve includes a valve body and at least one rotor disposed in and having the peripheral surface defining with said body at least one arcuate path for the flow of adhesive from an inlet to an outlet of said at least one valve, said peripheral surface including the at least one irregularity arranged to influence the flow of adhesive from said inlet to said outlet.
- 3. The apparatus of claim 2, wherein said at least one irregularity includes at least one of (a) at least one recess, (b) at least one groove, (c) at least one projection, and (d) at least one lobe.
- 4. The apparatus of claim 2, wherein said body includes a housing having a chamber for said at least one rotor.
- 5. The apparatus of claim 1, wherein said applicator has at least one adhesive storing chamber communicating with said at least one orifice.
- 6. The apparatus of claim 1, wherein said at least one orifice has at least one parameter, including the depth and the capacity thereof, which is variable to thus influence the quantity of adhesive being applied to the web by said applicator.
- 7. The apparatus of claim 1, wherein said orifice is adjustable.
- 8. The apparatus of claim 1, wherein said applicator has a first width, said at least one orifice has a second width, and at least one of said widths is adjustable.
- 9. The apparatus of claim 1, wherein said applicator has an arcuate web-contacting surface adjacent said course for the web.
- 10. The apparatus of claim 1, further comprising means for varying the pressure of adhesive in said connecting means.
- 11. The apparatus of claim 1, wherein said applicator includes a plurality of nozzles each having at least one adhesive-discharging orifice adjacent said course for the web, said connecting means including discrete conduits each connecting said at least one source with a different one of said nozzles, and further comprising means for individually selecting the pressure of adhesive in at least two of said conduits.
- 12. The apparatus of claim 1, wherein said applicator includes at least two nozzles each having at least one adhesive-discharging orifice adjacent said course, said connecting means including at least two conduits each connecting said at least one source with a different one of said nozzles, and further comprising means for maintaining the pressure of adhesive in one of said at least two conduits at a value which at least approximates the pressure of adhesive in the other of said at least two conduits.
- 13. The apparatus of claim 12, wherein said connecting means further includes an additional conduit communicating with said at least one source, said at least two conduits having inlets communicating with said additional conduit and said pressure maintaining means including at least one pump disposed in said additional conduit upstream of said inlets of said at least two conduits.
- 14. The apparatus of claim 1, wherein at least a portion of said applicator has a coat of a material opposing accumulations of adhesive on the applicator.
- 15. The apparatus of claim 1, further comprising means for monitoring at least one variable parameter of adhesive on the web.
- 16. The apparatus of claim 15, wherein said monitoring means includes means for ascertaining the quantity of adhesive being applied to the web.
- 17. The apparatus of claim 15, wherein said monitoring means includes means for generating signals denoting the monitored at least one parameter, and further comprising means for adjusting at least one of said source, said applicator, said connecting means and said regulating means as a function of said signals.
- 18. The apparatus of claim 1, wherein said applicator comprises a plurality of nozzles each having at least one orifice and said regulating means comprises a rotary valve for each of said nozzles, each of said valves including a valve body and a rotor disposed in and having the peripheral surface defining with said body at least one arcuate path for the flow of adhesive from an inlet to an outlet of the respective valve, said peripheral surface of each rotor including the at least one irregularity arranged to influence the flow of adhesive from the inlet to the outlet of the respective valve.
- 19. The apparatus of claim 18, wherein each of said peripheral surfaces is provided with a plurality of irregularities.
- 20. The apparatus of claim 1, further comprising means for advancing the web along said course at a first speed, means for rotating a rotor of said at least one valve at a second speed, and means for synchronizing the operation of said advancing means with the operation of said rotating means.
- 21. The apparatus of claim 1, comprising at least two sources respectively containing different first and second adhesives, said application including first and second nozzles each having at least one orifice adjacent said course for the web and said connecting means including at least one first conduit arranged to convey first adhesive from the respective source to said first nozzle and at least one second conduit arranged to convey second adhesive from the respective source to said second nozzle.
- 22. The apparatus of claim 1, wherein said valve has a hollow stator and a rotor rotatable in said stator about a predetermined axis, said stator and said rotor defining an arcuate groove disposed in a plane normal to said axis and extending from an inlet to an outlet of said valve.
- 23. The apparatus of claim 22, wherein said groove extends along an arc approximating but less than 360°.
- 24. The apparatus of claim 1, wherein said applicator includes a plurality of nozzles each having at least one orifice and each adjacent a different portion of said course, said connecting means including a plurality of conduits, at least one for each of said nozzles and each connecting said source with the respective nozzle.
- 25. The apparatus of claim 24, wherein said source includes a plurality of discrete sources of different adhesives, said conduits including at least two conduits connecting one of said discrete sources with the respective nozzles.
- 26. The apparatus of claim 24, wherein said regulating means includes a plurality of valves each having a hollow body and a rotor turnable in the respective body about a predetermined axis, each rotor having a peripheral surface defining with the respective body a path leading to one of said nozzles, said bodies and said rotors cooperating to confine the adhesive to flow to the respective nozzles.
- 27. The apparatus of claim 26, wherein said rotors constitute substantially disc-shaped sections of a rotor which is common to all of said valves, said hollow bodies forming part of a stator common to and surrounding all of said disc-shaped sections, the peripheral surface of each of said disc-shaped sections having at least one irregularity arranged to influence the flow of adhesive within the respective hollow body.
- 28. The apparatus of claim 27, wherein at least one of said disc-shaped sections cooperates with the respective hollow body to establish a seal against leakage of adhesive from the respective valve.
- 29. The apparatus of claim 26, wherein said hollow bodies have internal surfaces surrounding said rotor and provided with arcuate grooves for the flow of adhesive along the respective paths, said grooves having centers of curvature on said axis.
- 30. The apparatus of claim 29, wherein at least one of said grooves extends along an arc approximating but less than 360°.
- 31. The apparatus of claim 24, wherein at least one of said nozzles has at least one adhesive-storing chamber communicating with the respective at least one orifice.
Priority Claims (3)
Number |
Date |
Country |
Kind |
100 19 930 |
Apr 2000 |
DE |
|
01106122 |
Mar 2001 |
EP |
|
01109094 |
Apr 2001 |
EP |
|
US Referenced Citations (16)
Foreign Referenced Citations (11)
Number |
Date |
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10 10 891 |
Jun 1957 |
DE |
1 241 323 |
Mar 1967 |
DE |
28 45 342 |
Apr 1980 |
DE |
2 056 321 |
Mar 1981 |
DE |
39 09 990 |
Sep 1990 |
DE |
198 06 673 |
Aug 1998 |
DE |
197 14 029 |
Oct 1998 |
DE |
0 300 734 |
Jan 1989 |
EP |
1 147 716 |
Oct 2001 |
EP |
791 988 |
Dec 1935 |
FR |
458 443 |
Dec 1936 |
GB |