This application is the National Stage filing under 35 U.S.C. 371 of International Application No. PCT/EP2004/006737, filed Jun. 22, 2004, and claims priority of German Patent Application 103 29 219.5, filed Jun. 28, 2003.
The invention relates to a shaft rod, particularly for a heald shaft of a weaving machine, and includes the features of the preamble of claim 1. The invention further relates to a heald shaft provided with at least one of such a shaft rod.
Heald shafts of weaving machines are, as a rule, formed of a rectangular frame whose long sides are constituted by so-called shaft rods. Each shaft rod supports a shaft stave. Between the mutually parallel-arranged shaft staves healds are disposed which, by means of their end eyelets, are attached to the shaft staves. Each heald has at least one thread eyelet through which a warp thread extends which is moved by the motion of the heald shaft for shed forming. The healds are held on the shaft staves with a certain longitudinal play to enable them to freely align themselves in the lateral direction and to prevent them for being either compressed or extended. Such a play causes a continuous pounding or clattering of the healds against the shaft staves, creating a source of noise. Further, a stress on the healds is generated which may lead to heald breakage.
WO 01/48284 A1 discloses a heald shaft for a weaving machine. The shaft rods of the heald shaft each have a damping element on their sides facing the end eyelets of the healds. The damping element is arranged within the play range of the end eyelet, so that the latter may abut the damping element. Upon impact on the material having damping properties, lesser noise and mechanical stress on the heald are generated than in case of hard abutments.
The above principle is also realized according to U.S. Pat. No. 3,895,655 and Swiss Patent 588582.
Rubber or the like is being considered as the damping material. In the course of the threading step, the healds stand with their end eyelets on the lower damping element and remain suspended there by frictional engagement. Such a circumstance renders the thread-in of the healds more difficult. This is aggravated if a relatively small play is provided between the lower end eyelet and the damping element for the purpose of limiting the back-and-forth pounding of the healds in their longitudinal direction. If, on the other hand, a large play is provided for the operation, the damping effect remains limited.
It is therefore an object of the invention to provide a shaft rod which ensures a low-noise operation. It is further an object of the invention to provide a method of outfitting a heald shaft which includes at least one shaft rod as described above and where the thread-in of the healds may be effected in a manner as uncomplicated as possible.
The above objects generally are achieved according to a first aspect of the invention with a shaft rod, particularly for a heald or heddle shaft of a weaving machine, including:
The above objects generally are achieved according to a second aspect of the invention with a method of fitting a heald shaft with healds or heddles and/or threading threads into the healds, wherein the fitting step and/or the threading step is performed on a heald shaft; with the damping element from at least one shaft rod of the heald shaft having been removed, and
The shaft rod according to the invention comprises a damping element which is arranged in the vicinity of the shaft stave and which is transversely movably supported on the shaft rod. Thus, the damping element is supported for displacement in the longitudinal direction of the healds. Such an arrangement results in a reduction of the wear between the shaft stave and the healds. The heald motion is damped very effectively. Further, the damping measure avoids heald breakages and results in a noise reduction.
It is essential in the inventive shaft rod having a movable damping element that the healds be entrained, that is, pulled, by the shaft staves, and that during the entire motion process, a damping element lie on the healds by virtue of gravity affecting the element or by virtue of inertia. At the same time, the healds are freely movably supported and are damped only by the weight of the damping element. At the points of reversal of the direction of motion of the heald shaft, the damping elements assume, possibly briefly, a pushing function due to their elasticity. At the reversal points the healds slightly penetrate into the damping elements, so that the healds are gently, rather than abruptly braked to thereafter continue their motion in the opposite direction.
The loose support of the damping element on the shaft rod provides for the possibility of facilitating the fitting of the heald shaft with the healds. The damping element is not held fixedly on the heald shaft and thus may also move in the axial direction. This applies at least if, as preferred, the damping element has a constant cross section along its length. As a result, the heald shaft may be fitted with healds when the damping element is still absent during such a step. First, the warp threads may be threaded into the healds by a threading machine and thereafter the damping element is inserted into he heald shaft. The corresponding process steps are defined in the method claim.
The damping element is, for performing the process, preferably releasably connected to the heald shaft, that is, it is removably held thereon. It may be removed from its seat, for example, by a slight elastic deformation. In such an embodiment no longitudinal mobility of the damping element is required. It is, however, also possible, to pull the damping element longitudinally into its seat.
Further, the movable damping element provides for a reduction of the oscillations of the healds during operation of the weaving machine. This may lead to an improved appearance of the fabric. An oblique positioning of the healds as well as warp thread ruptures are prevented during operation.
In addition, the operating speed of the weaving machine and thus its productivity may be increased.
Further details of advantageous embodiments appear in the drawing, the description and the claims.
In the drawing, which illustrates examples of embodiments of the invention,
a are schematic cross-sectional views of a modified embodiment of a damping element,
The shaft rod 2 and the shaft rod 3 hold a respective shaft stave 6, 7 extending parallel to the respective shaft rod 2, 3. The shaft staves 6, 7 are flat, steel profile members, while the shaft rods 2, 3 are preferably extruded aluminum profile members. The heald shaft 1 has many, mutually parallel-arranged healds 8 which sit on the shaft staves 6, 7 by means of their end eyelets 9, 11.
At least at one, but preferably at both shaft rods 2, 3, respective damping elements 12, 13 are arranged in the immediate vicinity of the end eyelets 9, 11. The damping elements 12, 13 are supported on the shaft rods 2, 3 for displacement in the working direction of the heald shaft 1 as indicated by the arrow 14 in
In the present embodiment the shaft rods 2, 3 are of identical structure. For this reason, in the description which follows, only the shaft rod 2 will be discussed to represent both the shaft rods 2 and 3.
The shaft rod 2 illustrated in
In the buffer chamber 21 a damping element 12 is arranged which may be, for example, a cross-sectionally trapezoidal bar made of a damping material, such as plastic, a foam plastic, a plastic provided with hollow spaces, a synthetic fiber body or the like. The damping element may also be a bar or a strip made of a composite material (such as a metal-plastic composite, for example, a steel core having a plastic jacket), a jacketed foam body or a jacketed fiber body. The contour of the damping element conforms to the buffer chamber 21. At its side facing the planar securing web 18, the damping element has a planar surface. The carrier body 15 has, externally at its underside, an oblique engagement surface 26. At that location the damping element 12 has an engagement surface which too, is arranged obliquely, that is, at an obtuse angle to the securing web 18. The damping element 12 has likewise a planar surface at its outer side which is oriented parallel to the side wall 17. At the side facing the head 22, the damping element 12 may be provided with a strip-shaped planar surface or, if required, it may have a convexly or concavely bent surface. It is of importance that the largest possible distance shown in
In order to hold the damping element 12 securely in the buffer chamber 21, the shaft rod 2 is, for example at its side wall 17, provided with sheet metal securing members 27 to 33 (
The heald shaft 1 as described above, operates as follows:
Before use, the heald shaft 1 has to be fitted with the healds 8. For this purpose, the latter are slid onto the shaft staves 6, 7 from their ends. This manipulation occurs in the absence of at least the lower damping element 12, but preferably in the absence of both damping elements 12, 13. Thereafter the warp threads are threaded into the healds 8, that is, into their thread eyelet by means of a thread inserting machine. The warp threads have the tendency to extend in a linearly taut manner. As a result, they cause alignment of the healds 8, which sit with a large play on the shaft staves 6, 7, until the healds 8 have found their working position on the respective shaft staves 6, 7. At this point the damping elements 12, 13 may be inserted by sliding them, for example, with a certain elastic deformation, over the sheet metal securing members 27 to 33, into the buffer chamber 21 in which they will then loosely lie. In the alternative, the damping elements 12, 13 may be axially drawn in. As a further alternative, it is feasible to releasably connect, for example, by screws, the sheet metal securing members 27 to 33 with the carrier body 15. In such a case the sheet metal securing members 27 to 33 may be removed for facilitating the insertion of the damping elements 12, 13. In case of sufficient flexibility, the damping elements 12, 13 may also be introduced into the buffer chamber 21 through the gaps between the sheet metal securing elements 27 to 33.
After completion of the outfitting of the heald shaft 1, the weaving machine may start its normal operation, during which the heald shaft 1 is reciprocated very rapidly and with very abrupt motions in the direction of the arrow 14 (
In
In this instance, the damping element 12 has a circular cross section and again, is of a damping material. It is, for example, formed by a plastic bar, a rubber bar or the like. In the carrier body 15 the engagement surface 26 is formed which, in this embodiment, is constituted by a rounded trough. The engagement surface 26, together with a flat, wall-like rib 34 which extends parallel to the securing web 18, forms a receiving chamber for the damping element 12. The receiving chamber is part of the buffer chamber 21. In this embodiment, similarly to the previously described embodiments, a certain play is present between the securing web 18 and the frontal securing elements (the sheet metal securing elements 27 to 33) which are here replaced by the rib 34 which extends uninterruptedly in the longitudinal direction of the shaft rod 2.
By virtue of the above arrangement, between the engagement surface 26 and the damping element 12 an air cushion is enclosed which may develop a certain buffering effect. The damping element 12 may freely move in the buffer space 21 and thus it may engage the head 22 or, in the alternative, the engagement surface 26. In case the shaft rod 2 moves rapidly, the damping element 12 first lies on the head 22. Upon abrupt braking of the shaft rod 2, as it occurs during a change in the direction of motion, the damping element 12 and the healds 8, with their end eyelets 9, 11, penetrate into the buffer chamber 21, as a result of which the air cushion 35 is displaced. The latter then must escape past the damping element 12; this has a damping and thus an impact-reducing effect, particularly in case of very rapid braking steps.
It is further feasible to provide the rib 34, for purposes of controlling the escaping air cushion 35 or for saving weight, with apertures or interruptions in the shape of groove-like or slot-like milled-out portions.
The damping element 12 is in this instance a profile element having a damping cushion 37 which is joined by a web 38 passing through the slot. The web 38 extends perpendicularly from the damping cushion 37 into an inner chamber 39 surrounded, on the one hand, by the rear wall 18 and, on the other hand, by the rib 34. The inner chamber 39 is closed at the top by the engagement surface 26 which is engaged by a bead-like head region 41 formed at the free end of the web 38.
The damping element 12 has a play measured in the working direction (arrow 14). The range of play of the damping element 12 intersects—like in all the other previously described embodiments—the range of play of the end eyelet 9, that is, the damping element 12 and the head 22 may be in engagement with one another in any position inside the buffer chamber 21. In this embodiment too, as in the embodiment according to
A heald shaft 1 comprises at least one shaft rod 2 on which a damping element 12 is supported to be movable in the longitudinal direction of the heald. By virtue of movably supporting the damping element 12, an alignment of the healds 8 is improved and facilitated, and a desired damping effect is obtained during the entire motion course of the healds 8.
Number | Date | Country | Kind |
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103 29 219 | Jun 2003 | DE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/EP2004/006737 | 6/22/2004 | WO | 00 | 12/22/2005 |
Publishing Document | Publishing Date | Country | Kind |
---|---|---|---|
WO2005/001179 | 1/6/2005 | WO | A |
Number | Name | Date | Kind |
---|---|---|---|
2461496 | Kaufmann | Feb 1949 | A |
3895655 | Sujdak et al. | Jul 1975 | A |
4106530 | Kaufmann | Aug 1978 | A |
6009918 | Beyaert | Jan 2000 | A |
6230756 | Baumann et al. | May 2001 | B1 |
6789580 | Cardoen et al. | Sep 2004 | B1 |
6883554 | Baumann et al. | Apr 2005 | B2 |
6981527 | Froment | Jan 2006 | B2 |
6994122 | Cardoen et al. | Feb 2006 | B2 |
7036532 | Bauder et al. | May 2006 | B2 |
7147010 | Froment et al. | Dec 2006 | B2 |
7185679 | Schwemmlein et al. | Mar 2007 | B2 |
7204274 | Mettler | Apr 2007 | B2 |
20030150506 | Baumann et al. | Aug 2003 | A1 |
Number | Date | Country |
---|---|---|
588 582 | Jun 1977 | CH |
1 176 237 | Jan 2002 | EP |
10 001844 | Jan 1998 | JP |
WO-9726396 | Jul 1997 | WO |
WO-01-48284 | Jul 2001 | WO |
WO-2004057076 | Jul 2004 | WO |
WO-2004057077 | Jul 2004 | WO |
Number | Date | Country | |
---|---|---|---|
20060137759 A1 | Jun 2006 | US |