The present invention relates to tube filling machines, and more particularly to tube holders used with such machines.
Laminated thermoplastic tubes are commonly used for product packaging containing viscous materials. The nozzle and shoulder insert are typically thicker and more rigidly structured than the attached tubular sidewalls providing structure for the dispensing end and shaping for the tube. For unfilled tubes, the circular shoulders particularly help maintain the circularity of the adjoining sidewalls before the tubes are filled, at least closer to the nozzle end. The opposite end of the tube remains open and provides an entry into the internal cavity for filling the tube with the product. After filling the open end may be closed by crimping or capping.
The unfilled tubes are typically packaged and transported in bulk to the filling machine. The packaged tubes may be considerably deformed particularly at the sidewall area proximate to the open end which lacks support from the tube shoulder. The open end may partially collapse inwards and assume an oval cross sectional shape in which the sidewalls of the tube are no longer straight and parallel. This resulting ovality may interfere with the tube filling operation and product feed nozzles which are inserted into the open end of the tube. Tube filling machines can generally only tolerate ovality on the order of about 10%. This can limit the selection of tube materials to more rigid ones and the tube making process.
The ability to maintain circularity of the tube at the filling station is desired to reduce or eliminate the foregoing limitations.
The present invention may be directed, in one aspect, to a tube filling machine including a device operable to re-establish the circularity of a tube within acceptable ovality tolerances for filling.
In one embodiment, the invention can be a tube holder for carrying a tube to multiple processing stations of a tube filling machine. The tube holder includes a body comprising an open chamber configured for retaining a tube. The tube has an internal cavity for storing a product, a dispensing end, and an open filling end. A retractable tube shaping device is movably disposed in the body, the shaping device being movable between an extended position and a retracted position. When the shaping device is in the extended position, the shaping device engages the tube proximate to the open end and imparts a circular cross sectional shape to the tube for filling the cavity.
In another embodiment, the invention can be a tube holder for carrying a tube to multiple processing stations of a tube filling machine. The tube holder includes a body comprising an open circular chamber configured for retaining a tube in an upright position. The tube has an internal cavity for storing a product, a dispensing end, and an open filling end. A plurality of retractable straightening elements are movably disposed in the body and spaced circumferentially apart around the chamber. The straightening elements each comprise a bearing surface configured to engage the tube when seated in the chamber. The straightening elements vertically movable between an upward extended position and a downward retracted position. When the straightening elements are positioned to engage the tube proximate to the open end and impart a circular cross sectional shape to the tube for filling the cavity.
In a further embodiment, the invention can be a method for filling a tube. The method includes: providing a tube including an internal cavity, a dispensing end, and an open filling end; providing a tube holder configured to hold the tube in an upright position, the tube holder including a retractable tube shaping device; inserting the dispensing end of the tube into the tube holder; vertically extending a tube shaping device movably disposed in the tube holder from a top surface of the tube holder towards an extended position; engaging an upper portion of the tube proximate to the open filling end with the shaping device; conforming the cross sectional shape of the upper portion to a target filling reference circle; and filling the cavity of the tube with a product material. The method may further include vertically retracting the tube shaping device back towards the top surface of the tube holder towards a retracted position after filling the cavity of the tube.
Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.
The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:
10A is a top plan view of the tube holder and shaping device of
All drawings are schematic and not necessarily to scale.
The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.
The description of illustrative embodiments according to principles of the present invention is intended to be read in connection with the accompanying drawings, which are to be considered part of the entire written description. In the description of embodiments of the invention disclosed herein, any reference to direction or orientation is merely intended for convenience of description and is not intended in any way to limit the scope of the present invention. Relative terms such as “lower,” “upper,” “horizontal,” “vertical,” “above,” “below,” “up,” “down,” “top” and “bottom” as well as derivative thereof (e.g., “horizontally,” “downwardly,” “upwardly,” etc.) should be construed to refer to the orientation as then described or as shown in the drawing under discussion. These relative terms are for convenience of description only and do not require that the apparatus be constructed or operated in a particular orientation unless explicitly indicated as such. Terms such as “attached,” “affixed,” “connected,” “coupled,” “interconnected,” and similar refer to a relationship wherein structures are secured or attached to one another either directly or indirectly through intervening structures, as well as both movable or rigid attachments or relationships, unless expressly described otherwise. Moreover, the features and benefits of the invention are illustrated by reference to the exemplified embodiments. Accordingly, the invention expressly should not be limited to such exemplary embodiments illustrating some possible non-limiting combination of features that may exist alone or in other combinations of features; the scope of the invention being defined by the claims appended hereto.
A laminated tube is shown in
In one embodiment, the shoulder 60 and nozzle 62 may have thicker walls and be more structured than the sidewalls 56 which may be more flexible and resilient being subject to greater deformability. The sidewalls 56 may have a generally circular shape in cross section complementing and conforming to the shape of shoulder 60 (in top plan view best shown in
The product filled in the tube 50 may be any type of flowable composition or substance including solids (e.g. powder, granules, pellets, etc.), liquids, or viscous liquids such as pastes, gels, or creams of various types. In certain embodiments, for example without limitation, the product material may be an oral care material or a personal care material. Other types of products however may be used. Accordingly, the invention is not limited to the type of material emplaced in the tube.
Tube 50 may be formed of any type material. In one embodiment, the tube 50 may be a monolayer or multi-layered plastic tube formed of a suitable polymer selected for the product to be stored therein. The sidewalls 56, shoulder 60, and nozzle 62 may be formed of the same or different types of plastics. In some examples, the plastic may be a polyolefin thermoplastic such as polyethylene, polypropylene, or others.
Referring initially now to
A tube filling machine 100 includes a frame 101 supporting a moving conveyor 102 that transfers a tube holder 200 between process stations which may include tube supply, filling, sealing, and removal stations. The tube filling machine 100 thus operates to automatically fill and seal a plurality of tubes in sequential order with the intended product from start to finish in a continuous and efficient manner.
A movable carrier 104 is supported by the conveyor 102 which includes a plurality of receptacles 106 each configured for supporting a tube holder 200. Receptacles 106 may be in the form of a hole sized to at least partially allow insertion therein for retaining the tube holder 200. Tube holder 200 may include an annular flange 202 which engages the top surface 108 of carrier 104 to limit the insertion depth of the tube holder and support the holder. In certain embodiments, the carrier 104 may be a rotatable turntable or carousel which transports the tube holders 200 and tubes therein in a circular pattern between the various process stations positioned around conveyor 102 in the tube filling machine 100. In other possible arrangements, the carrier 104 may be a linearly movable apparatus in which the process stations are arranged along a linear path of the conveyor 102 from start to finish. Any type of process flow and equipment arrangement may thus be used with the present invention.
Tube filling machine 100 includes a drive mechanism 110 which is used to actuate the tube shaping device 301. The drive mechanism may be pneumatic, hydraulic, electric, or a combination thereof. The drive mechanism 110 may be separate from or a part of the conveyor drive equipment or other equipment of the tube filling machine that may control the other appurtenances provided such as tube sealing, empty tube fill loading to the carrier, or filled/sealed tube ejection operations.
A fill nozzle 112 may be supported by the frame 101 of the tube filling machine 100 and positioned above carrier 104. At the tube filling station, the end or tip of the nozzle is inserted into the open top filling end 54 of the tube 50 for introducing the product. In various embodiments, the nozzle 112 may remain stationary while the tube holder 200 is raised from the carrier 104 by a lifting mechanism of the tube filling machine 200 at the filling station (e.g. pneumatic, mechanical or electrically actuated drive member), or alternatively the tube holder 200 may remain stationary and seated in the carrier 104 while the fill nozzle is lowered. Either type of tube filling scenario and operation may be used with embodiments of the present invention.
Referring to
Chamber 206 may have a generally cylindrical shape defining a vertical centerline Cv including an upper portion 206A configured for holding sidewalls 56 of tube 50 and lower portion 206B configured to form a seat for holding tube shoulder 60 and dispensing nozzle 62. Lower portion 206B includes a reduced diameter section sized to receive the capped tube dispensing nozzle 62. Upper portion 206A has an open top 208 for inserting and receiving tube 50 for processing and filling in the tube filling machine 100. Chamber 206 has a complementary shape to the tube 50 intended to be carried therein.
Tube holder 200 may have a monolithic single unitary structure or may be formed of two or more sections (e.g., halves split vertically or horizontally) which are permanently or removably coupled together by suitable mechanical means (e.g. fasteners, welding, etc.). Tube holder 200 may be formed of any suitable metal or non-metal material. In some embodiments, without limitation, the holder 200 is made of metal such as aluminum, titanium, steel, etc. which is amenable to machining and forming.
A retractable tube shaping device 301 is provided for straightening the sidewalls 56 and top filling end 54 of tube 50 for filling. In a first embodiment shown in
In this present embodiment, bearing surfaces 306 are arcuately and concavely shaped to engage the convexly shaped circular sidewalls 56 of tube 50 (see, e.g.
It will be appreciated that other shapes may be used for tube bearing member 302 including various rectilinear and polygonal configurations so long a bearing surface 306 that engages tube 50 is provided. The invention is expressly not limited in shape therefore to the bearing member 306 shown and disclosed herein.
Actuator rod 302 may also have any suitable shape in transverse cross-section, including round, oblong, rectilinear (e.g. square or rectangular), and polygonal (e.g. triangular, hexagonal, trapezoidal, etc.). Other shapes may be used.
Referring to
Any suitable number of straightening elements 300 may be provided so long as any ovality present in tube 50 prior to filling may be reduced to within maximum acceptable ovality tolerance required by the tube filling machine for insertion of the filling nozzle 112 into the open filling end 54 of the tube. In certain embodiments, at least two diametrically opposed straightening elements 300 preferably may be provided. In other embodiments, three or four elements 300 may be provided. The number of straightening elements 300 will depend at in part to the circumferential extent or arc length of the bearing surfaces 306 provided on each element. Restraining the tube sidewalls 56 in at least two opposing locations with straightening elements 300 having relatively larger tube bearing members 302 and correspondingly sized surfaces 306 may be sufficient in some designs to force any ovality back within the desired circular shape needed for filling. In other designs having relatively smaller bearing members and surfaces 306, more straightening elements 300 may be needed to reduce the ovality. Importantly, it should be noted that because the resilient tube sidewalls 56 at the open filling end 54 will tend to return to their cylindrical shape when opposing inward radial straightening forces are applied against the sidewall surfaces normal to the vertical centerline Cv. Accordingly, an inwardly directed radial force need not be applied to the entire circumference of the tube sidewalls 56 in order to straighten and return them to a circular shape.
The straightening elements 300 may be formed of any suitable metal or non-metal material. In some embodiments, without limitation, the elements 300 are made of metal such as aluminum, titanium, steel, etc.
Straightening elements 300 with bearing surfaces 306 are vertically and linearly movable from a downward retracted position (see, e.g.
In the upward extended position, the bearing members are located more distally from the top surface and positioned to engage and straighten the upper portions of tube sidewalls 56. Advantageously, the ability to retract the straightening elements 300 ensures that the elements do not interfere with the process stations for initially loading the tubes 50 into the tube holder 200 and removing the tubes from holder. The straightening elements 300 are thus extended only when required to straighten the tube sidewalls 56 and remove any objectionable ovality for the tube filling operation.
In one embodiment, straightening elements 300 may be biased towards the retracted position by springs 218.
The tube straightening elements 300 are actuated by the drive mechanism 110 which may include drive members 114 for engaging actuator rods 302, as shown in
In an alternative embodiment shown in
Operation of the tube holder 200 and shaping device 301 will now be discussed. The goal of the shaping device 301 (e.g. straightening elements 300) is to bring any ovality of the upper tube portion and open filling end 54 back into specification within the maximum ovality acceptable tolerance. The maximum ovality acceptable tolerance may be visually represented by an imaginary target reference circle Rc illustrated in
Referring to
The upper portions of the tube sidewall 56 are assumed to still be partially collapsed inward imparting an oval cross-sectional shape to the tube as represented by the dashed-line oval shown in
At the same time or before the empty tube 50 reaches the filling station as shown in
The shaping device 301 continues to apply the radial force Fl against the tube sidewalls 56, thereby maintaining the circular shape of the filling end 54 at least until the fill nozzle 112 is inserted into the tube 50 as illustrated in
Once the tube 50 is filled with the desired product dispensed from fill nozzle 112, the shaping device 301 (e.g. straightening elements 300) may be returned to its downward retracted position shown in
It will be appreciated that numerous variations for filling a tube using shaping device 301 are possible.
In one embodiment, each sleeve 502 may include an integrally attached or formed actuator rod 304 disposed on the bottom of the sleeves. The rods 304 are vertically oriented and extend downwards from each sleeve 502. Each rod 304 include a springs218 and spring retention member 220 affixed to the bottom terminal end of the rod. The drive members 114 engage the retention members 220 to actuate the sleeves 502. The sleeves 502 may be positioned immediately adjacent to (and spaced apart from) the channel 206, or instead fully penetrate channel 206 thereby actually forming a movable sidewall portion of the channel 206. The sleeves 502 may extend vertically along the entire length or height of the channel 206 as shown. This positioning allows the sleeves 502 slidably engage the sidewalls 56 of tube 50. The sleeves 502 travel upwards and downwards in vertically-extending arcuately-shaped passageways 516 in tube holder body 204 which complements the shape and curvature of the sleeves. Other arrangements and configurations of sleeves 502 are possible.
In the present embodiment shown, at least two diametrically opposed sleeves 502 are provided. In other possible embodiments, three or more sleeves may be provided which may each have a smaller arc length or width than the two sleeve embodiment and ensure each quadrant of the tube sidewalls 56 is engaged.
As used throughout, ranges are used as shorthand for describing each and every value that is within the range. Any value within the range can be selected as the terminus of the range. In addition, all references cited herein are hereby incorporated by referenced in their entireties. In the event of a conflict in a definition in the present disclosure and that of a cited reference, the present disclosure controls.
While the foregoing description and drawings represent the exemplary embodiments of the present invention, it will be understood that various additions, modifications and substitutions may be made therein without departing from the spirit and scope of the present invention as defined in the accompanying claims. In particular, it will be clear to those skilled in the art that the present invention may be embodied in other specific forms, structures, arrangements, proportions, sizes, and with other elements, materials, and components, without departing from the spirit or essential characteristics thereof. One skilled in the art will appreciate that the invention may be used with many modifications of structure, arrangement, proportions, sizes, materials, and components and otherwise, used in the practice of the invention, which are particularly adapted to specific environments and operative requirements without departing from the principles of the present invention. The presently disclosed embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being defined by the appended claims, and not limited to the foregoing description or embodiments.
Filing Document | Filing Date | Country | Kind |
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PCT/US2015/015330 | 2/11/2015 | WO | 00 |