US3900050A

US3900050A - Reed dent arrangement

Info

Publication number: US3900050A
Application number: US436866A
Authority: US
Inventors: Edgar Strauss
Original assignee: Maschinenfabrik Rueti AG
Current assignee: Ruti Machinery Works Ltd; Maschinenfabrik Rueti AG
Priority date: 1973-02-02
Filing date: 1974-01-28
Publication date: 1975-08-19
Anticipated expiration: 1992-08-19
Also published as: ES422882A1; GB1418436A; SU527141A3; CH554433A; DE2404980A1; JPS49102969A; CS178164B2

Abstract

The disclosure is directed to a reed dent arrangement for a wave-motion loom in which the reed dents are arranged between laminar guide elements, have elongate, lamella-like shape, and travel at a narrow side on drive-cam means which imparts to them pivoting or rocking movements taking place about an axis extending perpendicular to their broad sides.

Description

1451 Aug. 19, 1975 Strauss REED DENT ARRANGEMENT 3,739,816 6/1973 Kramenic et a1. 139/12 5 1974 l [75] Inventor: Edgar Strauss, Ruti, Zurich, 3809l30 Strauss et a 89/12 Switzerland [73] Assignee: Ruti Machinery Works Ltd., Ruti, Primary Examiner1-1enry S. jaudon Zurich, Switzerland Attorney, Agent, or Firm-Donald D. Denton [22] Filed: Jan. 28, 1974 [21] Appl. No.: 436,866

[57] ABSTRACT [30] Foreign Application Priority Data Feb. 2, 1973 Switzerland 1540 73 The disclosure is directed to a feed dent arrangement for a wave-motion loom in which the reed dents are 52 U.S. C1 139/12; 139/192 arranged between laminar guide elements, have [51 Int. C1. D03D 47/26 gate, lamena'like shape, and travel at a narrow Side 58 Field 61 Search 139 12, 13, 16, 66 A, 79, drive-Cam means which imparts t9 them p g 9r 139/82 74/569 rocking movements taking place about an axis extending perpendicular to their broad sides. [56] References Cited UNITED STATES PATENTS 8 Claims, 8 Drawing Figures 3,124,164 3/1964 Ewing 139/12 PATENTEU AUG 1 91975 2x 20 23 27 Fl {f7 I I a) Fig.5 77

Q i A W REED DENT ARRANGEMENT BACKGROUND OF THE INVENTION In looms of the wave-motion type, the reed dents serve not only for beating up the weft threads but also for driving the shuttles. They drive the shuttles due to forces directed transversely of the broad side of the reed dents. If the drive camming means is constituted by a screw-shaft, then also this component affords, due to its helical pitch, a thrust force directed transversely of the broad side of the lamella-shaped reed dents. In order to prevent lateral compression (condensing) of the reed dents on mutual contact taking place, i.e. in order to prevent the reed dents from being crowded together due to the thrust force along the axis towards one side of the loom, and thereby pressed together, they are arranged between laminar guide elements and effect their rocking movement in thin interspaces provided between each two adjacent guide elements. In order that the reed dents may be as mobile as possible, the interspace is so dimensioned that some free space or a slight lateral clearance is available between the reed dent and the guide elements. It is a further important task of the guide elements to effect the supporting of the pivot about which the reed dents are rockable.

It has now been found that, due to the thinness of the reed dents (determined by textile requirements), incisions may be formed both in the pivot of the reed dents and also in the drive means for the latter. The drive means are preferably designed as screw-shafts provided with proviles made from a plastics material. In the case of these, it may additionally happen that the plastics is displaced laterally of the incisions formed.

Due to these circumstances and effects, the attempt might be made to design the reed dents to be thickened, to the extent that this is possible textile-wise. Thereby, the reed dents would, in the zone of the thickened dents portions, be layered one against the other without interspace. With this solution, however, it would no longer be possible to arrange guide elements between the reed dents. For reasons already mentioned, i.e. the condensing or crowding together of the reed dents, and also the provision of a carrier for the pivoting axis, it is indispensable to provide a guide element between each dent.

The closest prior art known to the applicant in connection with the invention presented in this application for Letters Patent is in British Patent No. 1,201,295.

SUMMARY These disadvantages are to be obviated by the pres ent invention. The invention is characterized in that each reed dent has, at least at one of the locations at which it bears on the drive camming means or on the pivot, a thickened portion. It will be appreciated that the above and other advantages will be apparent from the following description of the invention which will be discussed in greater detail with reference to examples of embodiments and with reference to the drawings, in

which:

FIG. I shows a cross-sectional view illustrating the reed dents and the assembly thereof with the remaining elements;

FIG. 2 is a plan view of the elements shown in FIG. 1 showing the profile of the driving earns;

FIG. 3 is a cross-sectional view taken along the line III-III of FIG. 1 showing reed dents with thickened portions;

FIG. 4 is a cross-sectional view along the line lV-IV of FIG. 1 showing the thickened portion of the reed dents;

FIG. 5 shows a reed dent according to the invention, as seen from the side, i.e. as viewed towards one of its broad sides;

FIG. 6 shows an elevational view of the reed dent according to FIG. 5 as viewed towards one of its narrow sides;

FIG. 7 shows a lateral view of a further embodiment of a reed dent; and

FIG. 8 a through d shows some examples of various types of thickened portions for reed dents.

DESCRIPTION OF PREFERRED EMBODIMENTS FIG. 1 shows two end positions of a reed dent 11, one depicted in black lines. The reed dent 11 is pivotal about a pivot axis 12. FIG. 2 shows how the reed dents 11 are aligned along the pivot axis 12. Each reed dent 11 is arranged between two guide elements 13. Two screw-shafts 14 have a profile so shaped that both screw-shafts 14 continuously bear at each reed dent 11. The profile of each screw-shaft 14 thus constitutes for each reed dent 11 a drive cam, whereby the reed dents are induced to perform pivoting or rocking movements, the direction of which is shown by the double headed arrow 15. The entire assembly of guide elements 13 and reed dents 11 with the pivot 12 is combined by rods 16 (only two thereof shown in FIG. 2) to constitute an assembly secured to the loom. The pivot 12 extends through the guide elements 13 in the direction perpendicular to the latter and is disposed in apertures formed in the latter. It is supported by the guide elements 13. FIG. 1 also shows shaft healds 17 by means of which sheds are formed from the warp threads 18. The woven fabric produced by the operation of the read dent arrangement has been designated 19.

FIG. 3 illustrates a cross-sectional view at the location designated IIIIII in FIG. 1. The reed dents 11 have thickened portions 20 extending along the periphery of the pivot 12 over that zone via which the reed dents 11 bear on the pivot 12. The guide elements 13 are formed with apertures 26 by means of which spaced is provided for the thickened portions 20, without the guiding of the reed dents 11 being thereby hindered by the elements 13. FIG. 4 (which is a cross-section at location IV-IV of FIG. 1) shows that the reed dents have furthermore a thickened portion 21 at that location at which they bear on the right-hand screw-shaft 14 in FIG. 1. In the case of the left-hand screw shaft 14 according to FIG. 1, there is a further corresponding thickened portion 21. The design of the reed dents 11 is best seen from FIGS. 5 and 6. Due to the provision of the thickened

portions

20 and 21, the formation of incisions both in the pivot 12 and also in the drive camming means 14 is prevented or at least very considerably reduced, Without its being necessary to accept the disadvantages resulting from thickened reed dents ll.

Hitherto, it had been necessary to impart a certain degree of width enlargement to the reed dent according to FIG. 5, so as to secure it against tilting or tipping. According to the example shown, the thickened portions 20 are so selected that they are able to contact each other with only a small clearance or play. Therewith also, the danger of tilting is eliminated, so that the aforementioned width enlargement" of the reed dents 11 is no longer necessary. Thus, it is possible to employ reed dents 22 such as have the narrower shape shown in FIG. 7. These have the important advantage that the pivot 12 no longer requires to be pushed through a closed aperture in the read dent 22, since the latter is downwardly open at its pivot-point. This has again the advantage of extremely ready replaceability and also lower reed dent weight.

The thickened

portions

20, 21 may be of varying shapes and sizes. They may, for example as shown in FIG. 8a with regard to the thickened portion 20, be constituted by strips which are hard-brazed onto the body of the reed dent. Of course, it is possible to employ also such a welded-on strip for the thickened portions 21. On punching out the laminar reed dents, it will be possible to leave standing a projecting strip 23 which is bent over, thus affording'a shape according to FIG. 8b. The embodiment shown in FIG. 80 is suitable for the thickened portions and 21. It is manufactured in a pressing step and can be employed in particular in the case of reed dents made from plastics. Referring to FIG. 8d, the thickened portion comprises a U-shaped strip applied along a longitudinal edge of the reed dent 11. In particular in cases wherein the thickened portion 21 is made from plastics, this embodiment is suitable also for the thickened portion 20.

In operation of the loom, the rocking movements of the reed dents 1] follow each other, one after the other, in the sequence of their arrangement along the pivot 12. The pivoting of two adjacent reed dents relativev to each other is always relatively small. However, it is necessary to ensure that, in the case of the embodiments according to FIGS. 8b, c, d, the thickened portion 21 of one of the reed dents always remains in lateral abutment against the adjacent reed dent 11 at least over a small zone, in order to exclude any possibility of jamming or impingement of a thickened portion with its adjacent reed dent. In the case of the embodiment according to 8d, it is correspondingly necessary that, in all pivoting positions, the adjacent thickened portions 21 should remain continuously in lateral abutment. In order that this may be the case, the maximal, mutual pivoting or rocking of immediately adjacent reed dents *11 at the location of the end adjacent the pivot 12 of a thickened portion 21 must, as to length, be smaller than the width of the thickened portion 21.

In connection with the showing in FIG. 4, it should also be pointed out that the maximum forces at the reed dents 11 occur during weft beat-up. This is the case when the reed dents 11 travel on the highest portion of the screw-shaft 14. It will be perceived that, under these circumstances, the thickened portions 21 bear flat at their broad side on the surface of the screw shaft 14, so that the pressure per surface unit remains at a low level. Additionally, relatively large forces occur at the commencement of acceleration of the ends of the reed dents 11 projecting out of the guide element 13 assembly, in the upward direction. This is the case approximately at the location 24. There again, the thickened portions 21 bear more or less parallel to the surface of the screw-shaft 14.

If the shape illustrated of the reed dents is compared with the possibility, mentioned at the outset, for utiliz- 4 ing generally thicker reed dents, then it will be apparent that the construction according to the present invention has, additionally, the advantage that due to the interspaces available between the reed dents 11 and the guide elements 13 fibers which fly about" are not readily caught up and if some should be so caught up they can be blown away or they are automatically eliminated.

Diminution of wear or formation of incisions is achieved if, at least at one location at which the reed dents 11 bear on the drive camming means 14 or on the pivot 12, a thickened

portion

21 or 20 is provided.

It will be appreciated that various changes and modifications may be made within the skill of the art without departing from the spirit and scope of the invention illustrated and described herein.

What is claimed is:

1. A reed dent arrangement for a wave-motion loom wherein the reed dents are arranged between laminar guide elements, are of elongate lamella-like shape, and travel at one narrow side on a drive camming means due to which there are imparted to them. a rocking movement which takes place about a pivot extending perpendicular to their broad sides, characterized in that each reed dent has at least at one location a thickened portion which bears on said drive camming means and said pivot, and in those zones over which the thickened portions extend and over which they travel, the guide elements are formed with recesses.

2. The reed dent arrangement according to claim 1 in which said thickened portion is constituted by an elongate element secured to the reed dent and extending along its longitudinal edge which passes into abutment.

3. The reed dent arrangement according to claim 2 in which said thickened portion is constituted by a strip-shaped element secured to a lateral face of said reed dent.

4. The reed dent arrangement according to claim 3 in which the thickened portion is constituted by an elongate, narrow, U-shaped element secured to said reed dent.

5. The reed dent arrangement according to claim 1 in which each reed dent has a thickened portion at all locations at which it bears on the drive camming means.

6. The reed dent arrangement according to claim 1 in which said thickened portions bearing on said drive camming means have a width at least equal to the maximum rocking of directly adjacent reed dents relative to each other at the location of the end adjacent the pivot of the said thickened portions.

7. The reed dent arrangement according to claim 1 in which, in the case of thickened portions provided at the location of abutment of the reed dent at the pivot, a maximum minimal interspace is provided for maximum allowable play.

8. The reed dent arrangement according to claim 7, for a rocking shaft loom, wherein the drive camming means is disposed on one of the narrow sides of the reed dent, characterized in that each of the reed dents bears in a recess at the pivot which is located on the narrow side of the reed dent opposite the camming means and which at maximum half embraces the pivot.

Claims

1. A reed dent arrangement for a wave-motion loom wherein the reed dents are arranged between laminar guide elements, are of elongate lameLla-like shape, and travel at one narrow side on a drive camming means due to which there are imparted to them a rocking movement which takes place about a pivot extending perpendicular to their broad sides, characterized in that each reed dent has at least at one location a thickened portion which bears on said drive camming means and said pivot, and in those zones over which the thickened portions extend and over which they travel, the guide elements are formed with recesses.