Textiles: weaving – Fabrics – Drier felts
Reexamination Certificate
2000-05-26
2003-04-29
Calvert, John J. (Department: 3765)
Textiles: weaving
Fabrics
Drier felts
C028S141000, C028S208000
Reexamination Certificate
active
06554029
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a method for mounting a harness on a seam weaving machine, an apparatus for making a flat woven fabric endless by means of a woven seam joining together opposite ends of the fabric and a harness carriage for use in the harness mounting method. Forming fabrics used in the wet end section of papermaking machines have to be made endless by a woven seam. The weave pattern is continued exactly in the woven seam so that the joining does not cause markings in the paper.
2. Related Prior Art
U.S. Pat. No. 4,581,794 and U.S. Pat. No. 4,557,025 disclose an automatic seaming machine for forming a seam in a length of woven fabric for joining opposite ends of the fabric together thereby to form an endless woven fabric belt. When using that machine, a strip of woven material, cut from one of the ends of the fabric, the so-called seam strip, is supported between the opposite ends of the fabric. The seam strip is clamped at one end and weights or springs are attached to the opposite end of this seam strip so that it is pulled taut. The warp threads are removed from the seam strip located between the opposite ends of the fabric leaving only the weft threads. The weft threads of the seam strip are drawn in through a shedding mechanism and are controlled by means of a Jacquard machine to form a shed opening. The opposite ends of the fabric each include a fringe formed by removing a majority of the weft threads within an end portion of approx. 20 cm. A few weft threads are left at the edge of the fringe to form a narrow lease functioning to maintain the warp threads of the fringe in the proper position and sequence and to maintain proper relative alignment of the warp threads with respect to each other. The woven seam is formed by separating a first one of the warp threads of the lease and drawing it through the shed opening formed by the weft threads of the seam strip. The shed is then changed and a warp thread drawn out of the lease at the opposite end of the strip is separated and woven into the weft threads of the seam strip. This cycle is repeated until a seam has been woven along the entire width of the fabric. The warp thread fringes and seam strip weft threads reproduce within the woven seam exactly the weave pattern of the fabric because the fabric has been thermoset after weaving so that the warp and weft threads of the fabric, which are synthetic monofilaments, are permanently crimped. The warp thread fringes and the seam strip weft threads will be forced by their thermoset crimp knuckles to cross each other exactly as in the fabric.
The automatic seam weaving machine comprises a Jacquard machine carriage which supports the Jacquard machine and the shedding mechanism including the heddling assembly and the spring box. A plurality of eyeletted heddles are mounted between the springs of the spring box and the vertically reciprocal hooks of the Jacquard machine. The heddles are designed such that they can be slidably placed over the weft threads so that the individual weft threads do not have to be threaded through the heddles. The heddling assembly is fixedly mounted on the Jacquard machine.
U.S. Pat. No. 5,386,854 discloses a seam weaving machine wherein the Jacquard machine is arranged slightly offset underneath the shedding mechanism, a plurality of harness cords extending vertically downward from the jacquard machine and being deflected by 180° prior to passage through the shedding mechanism to return springs secured in the machine above the shedding mechanism.
U.S. Pat. No. 4,862,566 discloses an auxiliary device for a seam weaving machine. The auxiliary device couples each seam strip weft thread drawn in through one of the heddles to a tensioning string of a tensioning device. Said auxiliary device simplifies the drawing in of the seam strip weft threads through the heddles of the shedding mechanism.
U.S. Pat. No. 5,791,382 discloses a separable collar or coupling for the harness of the Jacquard machine. The separable collar enables a simple and quick connection and disconnection of a twine to one or several harness cords which in turn are fastened to the eyeletted heddles.
U.S. Pat. No. 5,636,663 discloses a harness system for weaving looms wherein all twines are releasably connected to one or several harness cords by means of couplings. The harness cords pass through openings in a plate which is reciprocally moveable so as to connect or disconnect all of the couplings simultaneously. In this way, the Jacquard machine can be disconnected from and reconnected to the shedding mechanism without the need to disconnect and connect each twine individually from the harness cords. A similar device for disconnecting and connecting a plurality of twines to harness cords collectively and simultaneously is disclosed in German Patent DE 42 13 958.
The width of the heddling assembly and the number of heddles or eyelets are fixed so that only small variations in the width of a woven seam and the density of the weft threads are possible with a specific heddling assembly. Each seam weaving machine can, therefore, be used only for fabrics within a narrow range of weave parameters. If a rather coarse fabric has to be made endless following a fine fabric on the same machine, the shedding mechanism has to be disconnected from the Jacquard machine and replaced by a shedding mechanism adapted to the coarser fabric. Such conversion of a seam weaving machine requires several days because each twine has to be disconnected from the harness cords of the previous shedding mechanism and reconnected to the harness cords of the new shedding mechanism separately.
Even if a fabric having the same parameters as the previous one has to be made endless, a standstill of several hours occurs because a new harness has to be drawn in, i.e. a new set of the seam strip weft threads has to be drawn in, through the eyeletted heddles or the eyelets. A Jacquard machine as used for a seam weaving machine includes, for example, 896 cords. Depending on the complexity of the weave pattern, it takes about 2 to 8 hours to draw in a new harness. A typical forming fabric for use in the wet end section of a papermaking machine has an average width of 7 meters. The opposite ends of such a fabric can be made endless by means of a seam weaving machine within about 10 to 15 hours. A standstill of several hours is, therefore, a considerable economic factor.
The weft threads of the seam strip cut from the fabric are arranged to form a shed opening so that they are used as or function as the warp thread in the seam weaving machine. Similarly, the warp thread fringes are drawn in through the shed opening so that they are used as or function as the weft threads in the seam weaving machine. The designations “weft threads” and “warp threads” are used here in accordance with the arrangement the threads had in the fabric rather than in accordance with their function in the seam weaving machine.
BRIEF SUMMARY OF THE INVENTION
The present invention provides a technique for adapting the design of a seam weaving machine quickly and without extended standstill periods of the seam weaving machine to the weave pattern and parameters of different fabrics. The improvement includes preparing the harness for a fabric having parameters differing from those of the previous fabric while the shedding mechanism is removed from the seam weaving machine and mounting the prepared shedding mechanism on the seam weaving machine, the twines and harness cords being coupled collectively.
Thus, in one aspect, the present invention provides a method for mounting a new harness on a seam weaving machine for making endless a flat woven fabric formed by interwoven warp and weft threads by means of a woven seam joining together opposite ends of the fabric, the opposite ends of the fabric each including a fringe of warp threads, the warp threads of the fringe being supported such that they can be interwoven with weft threads taken out of the fabric and drawn in through a shedding mechanism controlled
Gluck Ernst
Hacker Hans Eugen
Hofstetter Edgar
Calvert John J.
Graybeal Jackson Haley LLP
Muromoto Jr. Robert H
Wagner Finckh GmbH
LandOfFree
Method for mounting a new harness on a seam weaving machine,... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for mounting a new harness on a seam weaving machine,..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for mounting a new harness on a seam weaving machine,... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3112309