The invention relates to a method for producing a fabric which has both plain weaves comprising weft and warp threads and leno weaves comprising weft and warp threads according to the features of the pre-characterising clause of patent claim 1, and a loom for carrying out the method according to the features of the pre-characterising clause of patent claim 4 and 12.
The invention further relates to a shoulder blade for a blade and needle shaft of the loom mentioned in claim 4 and 12.
DE-PS 360 112 discloses a needle shaft device for producing types of fabric with alternate plain and leno weave.
The shafts are raised in a controlled manner in this instance by the slay being retracted by means of a carrier which is connected to the slay arm. By changing the manner in which the shafts are raised, it is possible to produce plain weave, and by successively raising the same shaft with lateral displacement thereof, it is possible to produce leno weave. In order to form the leno shed, a conventional shaft is laterally displaced with the shed in the closed state so that the warp threads of this shaft can be guided over the needle tips and warp threads of the other shaft which is a needle shaft.
If the needle shaft over whose needle tips the warp threads of the second shaft, that is to say, the conventional shaft, have been guided is raised, the leno shed is formed.
When the plain shed is formed, the lateral displacement of the warp threads is dispensed with; the shafts are raised alternately at regular intervals.
From the sequence described for forming a leno and plain shed, it can be seen that a fabric having alternate plain and leno weaves can be produced, that is to say, a plain weave can first be formed in the fabric and subsequently a leno weave. It is not disclosed how, during a weaving cycle, that is to say, from one reed beat-up operation to the next, both a plain weave fabric and a leno weave fabric can be produced.
Consequently, it is not disclosed what means could be provided for simultaneously producing weaves of this type in a fabric.
A device for producing a fabric having plain weaves and leno weaves is known from DE-PS 646 462 and has two needle combs which are located one above the other in one plane.
The needle combs are controlled independently of each other, whereby it is possible to change the weave during operation of the loom in such a manner that, after one or more leno weaves, plain weaves can also be produced.
However, the document does not disclose how plain and leno weaves can be formed in a fabric at the same time and what means are used for the production thereof.
A loom for producing a fabric comprising stationary, leno and weft threads is known from DE 101 28 538 A1.
This document also does not disclose how plain or leno weaves can be produced simultaneously during the production of fabric.
The object of the invention is to produce plain and leno weaves in a fabric which is to be produced during a weaving cycle, without the use of costly shed-forming means. The object is achieved with a method and a loom for carrying out the method.
In accordance with the method according to the invention, it is possible to form plain and leno weaves in a fabric which is to be produced simultaneously during a weaving cycle.
In one configuration of the invention, there is provision, in order to form the plain weaves, for the mutually adjacent warp threads which are used to form a lower shed and an upper shed to be raised alternately by one and the same blade and needle shaft from the position of the lower shed into the position of the upper shed and conversely to be guided back into the position of the lower shed again.
At the same time as the plain shed is formed, the formation of the leno shed is brought about using the same blade and needle shaft in such a manner that only the warp threads which are used to form the leno upper shed are raised in a manner known per se.
In the case of a substantially raised plain and leno shed, in a manner known per se, at least one weft thread is inserted into the shed. The weft thread which has been inserted is subsequently beaten-up to the fabric edge.
When the at least one weft thread is beaten-up, the second blade and needle shaft which has raised the warp threads to form the upper shed moves over the shed closure into the lower shed position. At the same time, the first blade and needle shaft is displaced transversely relative to the path of the warp threads so that the warp threads which are guided into the first blade and needle shaft are displaced laterally back or forth relative to the warp threads which are guided in the second blade and needle shaft. When the warp threads are laterally displaced, the warp threads which previously formed the plain upper shed instead now form the plain lower shed, whilst the warp threads of the original plain lower shed are used to form a new plain upper shed and, at the same time, the warp threads originally used to form the leno upper shed are again used to form a leno upper shed.
Using this method of operation disclosed above for the first and second blade and needle shaft, a plain weave and a leno weave are produced simultaneously during a weaving cycle.
In the case of light medical dressing material which is, for example, woven as a strip in plain weave, it is possible to dispense with separate leno devices for producing secure fabric edges since, in accordance with the method according to the invention, plain weave can be carried out together with at least one leno weave at the fabric edges of the strip using only two blade and needle shafts.
In order to carry out the method according to the invention, a loom is provided which has means for forming a shed, means for inserting weft threads into the shed which has been formed and means for beating-up the weft thread which has been inserted into the shed to the beating-up edge of the fabric to be produced.
The means for forming the shed comprise, in known manner, a first blade and needle shaft which is connected to a drive which allows the first blade and needle shaft to move back and forth in an oscillating manner transversely relative to the warp threads and therefore relative to the weaving plane.
The means for forming the shed further comprise a second blade and needle shaft which is located beside the first blade and needle shaft and which is connected to a suitable means which acts in a rotationally fixed manner on a shaft which is arranged remote from the slay shaft of the loom, the driving action of this shaft being directed away from the slay shaft.
In order to form plain and leno weaves simultaneously in a fabric, there is provision according to the invention for a needle blade having thread guiding eyelets which are directed away from each other to be connected in each case between two of the rod blades which are arrested at the upper and lower shaft connection of the first and second blade and needle shaft on a portion of the operating width of the first and second blade and needle shaft intended for forming leno weaves, and for a plurality of mutually spaced-apart rod blades to be arranged beside each other in the first blade and needle shaft closest to the slay of the loom on another portion of the operating width of the first and second blade and needle shaft intended for forming plain weaves, with which rod blades there is associated a so-called shoulder blade, having a shoulder at one or both sides, in the second blade and needle shaft either of each even-numbered or each odd-numbered rod blade of the first blade and needle shaft. In another configuration of the invention, the shoulder blades comprise an elongate, planar member which is preferably of metal and which, according to the invention, has, at one location of the longitudinal extent thereof, a laterally protruding first and second shoulder on which a warp thread from the lower shed of the warp is guided into the upper shed and conversely from the position of the upper shed into the position of the lower shed at alternate sides in order to form a plain shed.
The shoulder may have a special construction; the shoulder may have a trough-like recess in order to be able to raise and lower the warp thread in a secure manner; the face of the shoulder which carries the warp thread can be planar and orientated at an angle α≦90° relative to the longitudinal extent (longitudinal axis of the shoulder blade).
The protruding shoulders can be connected to the elongate member by means of a non-releasable connection and enclose an angle β<180°.
However, each shoulder blade can also comprise a first elongate, planar member having a shoulder which is bent out from the planar side of the member and a second member which is constructed as a mirror image of the first member. Both members are then joined together in the upper and lower shaft connection of the blade and needle shaft in such a manner that these members form the shoulder blade having shoulders which are directed away from each other.
In another configuration of the invention, in order to form the plain weave fabric, each of the even-numbered or each of the odd-numbered rod blades of the first blade and needle shaft, that is to say, the blade and needle shaft which moves transversely, that is to say, horizontally relative to the weaving plane may have a shoulder blade which has at least a shoulder at one side for retaining the plain weave warp threads which are not involved in forming the upper shed. The shoulder of the shoulder blades that retains the plain weave warp thread is formed substantially in the plane of the thread guiding eyelet of the needle blades of the first blade and needle shaft.
In a preferred configuration, the shoulder is in the form of a trough-like recess which is open downwards. In contrast, the shoulder of the shoulder blades of the second blade and needle shaft forms a trough-like recess which is open upwards. In another configuration of the invention, the shoulder blade is in the form of an elongate planar member which is preferably of metal and which has, at one side in the region of the longitudinal extent thereof, a shoulder which is directed counter to the supply direction of the warp.
Instead of the shoulder, it is possible to provide a trough-like recess in the corresponding rod blade in the relevant region of the longitudinal extent thereof. The trough-like recess terminates in a hook shape.
The recess may further have different geometric configurations; the important aspect is for the relevant warp thread to be able to be collected through the respective recess in the rod blade of the first blade and needle shaft and to be retained in the predetermined position thereof when the shed is formed.
Using the solutions according to the invention it is for the first time possible to produce fabrics in plain weaves and leno weaves during a weaving cycle on looms having no additional shed forming machine including shafts having healds and beams.
Since additional shafts are dispensed with, the front shed can have a shorter construction in looms of this type. The warp threads of the lower shed are relatively undisturbed so that, for example, in air jet looms, the lower shed is not displaced a large distance below the lower projection of the weft insertion duct which extends in the reed.
With the solution according to the invention, a retainer for the warp threads is also advantageously dispensed with in the region of the rear shed; warp thread holders in the region of the shed forming devices are completely avoided and fabric having faulty plain weaving is prevented.
Further advantageous effects of the invention will be appreciated from the patent claims and the following embodiments.
The invention is explained in greater detail below with reference to one embodiment and the appended drawings, in which:
The loom which is schematically illustrated in
The insertion of a weft thread into the insertion duct of a weaving reed 5 which is mounted on a slay 6 takes place within the period of time in which a shed 7 is formed in each case, that is to say, the blade and needle shaft 4 is located in the position thereof illustrated in
Using a movement sequence of this type, the fabric is produced in leno weave 15, see also
To this end, the blade and needle shaft 4 has, in addition to the usual rod blades 10 and the so-called needle blades 11 having a thread guiding eyelet 11a, see also
The fabric 9 produced is directed, according to
The rollers mentioned are rotatably supported in a partially illustrated machine frame 23 which also carries the fabric table 17.
The drives which are associated with the rollers are known per se and are not illustrated in greater detail.
In the region between the point 24a of the backrest 24 and the blade and needle shafts 3, 4, the warp threads 1L, 1D and 2L, 2D extend through a warp thread stop motion device 25 whose blades 26 which travel on the warp threads 1L, 1D; 2L, 2D and the warp threads 1L, 1D; 2L, 2D are readily accessible in an unimpeded manner from above in the event of a warp thread breakage.
The slay 6 having the weaving reed 5 is securely connected, by means of supports 27, to a shaft, the so-called slay shaft 28, which is rotatably supported in the machine frame 23 and which carries out an oscillating rotation movement and about whose axis of rotation it carries out a back and forth movement which serves to beat up the weft thread.
The drive action of the slay shaft is generally known, so no further explanations are required in this regard.
The basic construction of the blade and needle shafts 3, 4 can be seen in
The blade and needle shafts 3, 4 have a lower shaft connection 29 and an upper shaft connection 30. Both shaft connections are surrounded by a frame, the so-called shaft frame 31.
Both blade and needle shafts 3, 4 have a plurality of rod blades 10 which are arranged in a mutually spaced-apart manner and whose respective ends are anchored in the upper and lower shaft connection 30, 29.
In order to be able to simultaneously form, in accordance with the method according to the invention, a plain weave 16 and a leno weave 15 in a fabric 9, as illustrated in
Furthermore, a needle blade 11 having a thread guiding eyelet 11a is arranged in each case between two rod blades 10 on a second longitudinal portion of the cloth width of the blade and needle shaft 3 identical to the first longitudinal portion. The thread guiding eyelets 11a of the needle blades 11 of both blade and needle shafts 3, 4 are directed away from each other.
A shoulder blade 12 according to the invention is illustrated in
The shoulder blade 12 comprises in this instance a first single rod blade 13 having a so-called half shoulder 13a and a second single rod blade 14 having a half shoulder 14a. Both half shoulders 13a, 14a in this instance have a trough-like recess as a temporary warp thread carrier.
In
According to the sectional illustration A-A in
The method for producing a fabric with plain weaves and leno weaves being formed at the same time will now be explained with reference to
The blade and needle shafts 3,4 which are schematically illustrated in
Only the blade and needle shaft 4 additionally has shoulder blades 12.
The blade and needle shaft 3 carries out an oscillating back and forth movement transversely relative to the supply of the warp threads 1L, 1D; 2L, 2D. The back and forth movement is indicated by the directional arrow 32.
The blade and needle shaft 4 carries out a substantially vertically oscillating upward and downward movement, as indicated by the directional arrow 33.
The warp threads 1L, 2L are drawn into the gaps between the shoulder blades 12 and the rod blades 10 of the blade and needle shaft 4 on the one hand and into the gaps between the rod blades of the blade and needle shaft 3 on the other hand, in order to form a plain weave 16. A warp thread 1D is in each case drawn into the thread guiding eyelet 11a of each needle blade 11 of the blade and needle shaft 4 and a warp thread 2D is in each case drawn into the thread guiding eyelet 11a of each needle blade 11 of the blade and needle shaft 3 in order to produce a leno weave.
When the shaft 4 is lowered into the lower shed, in accordance with the direction of the downwardly directed double-headed arrow 33, this corresponds in
In the same manner, all the warp threads 2D of the blade and needle shaft 4 which have been guided through the thread guiding eyelets 11a are moved out of the position of the lower shed into the position of the upper shed, whereby the warp threads 1D and 2D form a leno weave.
Subsequently, a weft thread 34 is inserted into the plain and leno shed 7 formed, is beaten-up to the connection point 8 by the weaving reed 7 according to
In another configuration of the invention, the means for producing a fabric having plain weaves and leno weaves according to
The warp threads mentioned are, starting from the connection point 8 of the fabric 9, successively drawn into a weaving reed 5 which is driven in a pivoting manner so as to move about the centre axis 28a of the slay shaft 28, into a first blade and needle shaft 3 which is movingly driven back and forth transversely relative to the weaving plane 35 and into a second blade and needle shaft 4 which is driven in a pivoting manner so as to move about the centre axis 36a of a pivoting arm shaft 36 which is located remote from the weaving reed shaft.
As already disclosed above, the first blade and needle shaft 3 has a plurality of rod blades 10 and, at locations provided in each case between two rod blades 10, a needle blade 11 having a thread guiding eyelet 11a, see also
The warp threads 1L and 2L are alternately received between the rod blades 10 of the first blade and needle shaft 3 in order to form a plain weave fabric 9 whilst a warp thread 1D is guided in each thread guiding eyelet 11a of the needle blades 11 in order to form a leno weave fabric 9 or a leno edge as a closure for a plain weave fabric portion.
Accordingly, the second blade and needle shaft 4 also has a plurality of rod blades 10, a so-called shoulder blade 12 being positioned between two rod blades 10 in each case in order to form the plain weaves, which shoulder blade 12 has a shoulder 13a, 14a for alternately receiving a warp thread 1L or 2L. In the blade and needle shaft 4, a needle blade 11 having a thread guiding eyelet 11a is also provided at locations provided in each case between two rod blades 10 and, together with the needle blades 11 having a thread guiding eyelet 11a of the first blade and needle shaft 3, forms the leno weave fabric 9 or single leno weaves.
In another configuration of the invention, in order to prevent faulty plain weave fabric 9 caused by hooking warp threads in the region of the rear shed 7a, a shoulder blade 12 is also arranged alternately between each even-numbered or each odd-numbered rod blade 10 of the first blade and needle shaft 3 or the relevant rod blade 10 is constructed as a shoulder blade 12, with a trough-like recess 13a which terminates substantially in a hook and which is vertically open downwards in order to alternately retain the warp threads 1L or 2L if these are not moved into the upper shed during shed formation by the second blade and needle shaft 4, see also FIGS. 11 to 14.
The means for forming a shed 7 which is formed by an upper shed and a lower shed comprise in this instance the second blade and needle shaft 4 having the above-mentioned rod, shoulder and needle blades.
The blade and needle shaft 4 is connected to the lower connection 4a thereof at the free end of at least one pivoting arm 37 which engages on the pivoting arm shaft 36 in a rotationally secure manner.
The pivoting arm shaft 36 has a connection tab 38. The slay shaft 28 is also equipped with a connection tab 39. Both connection tabs 38, 39 are coupled by means of a rod 40.
In
Whilst in this position, the first blade and needle shaft 3 is moved by means of a drive which is not illustrated in this instance, according to
Owing to the fact that the relevant rod blades of the first blade and needle shaft 3 are also in the form of shoulder blades 12 and the relevant warp thread 1L or 2L is retained during the production of the shed, weaving errors in the plain weave fabric are prevented.
Number | Date | Country | Kind |
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103 07 489.9 | Feb 2003 | DE | national |
103 34 359.8 | Jul 2003 | DE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/DE04/00293 | 2/18/2004 | WO | 8/30/2005 |