WO2000055407A1

WO2000055407A1 - Heald made of strip material with shaped heald eye, method of its production, and a former for its production

Info

Publication number: WO2000055407A1
Application number: PCT/CZ2000/000013
Authority: WO
Inventors: Jiří JAKOUBĚ; Jiří VOPLAKAL
Original assignee: Seco, A.S.
Priority date: 1999-03-16
Filing date: 2000-03-08
Publication date: 2000-09-21
Also published as: CZ9900905A3; AU2793100A; CZ287292B6

Abstract

A heald (1) made of strip material with distributed heald eye (2) with heald eye (2) arms (21, 22) distributed by a plane distribution in the distribution area whose length is superior to the height of the heald eye (2). The invention also relates to a method of distribution of the heald eye in which the heald (1) is gripped between the shaping surfaces (31, 32, 331, 341) of a former (3) along a length superior to the height of the heald eye (2) overlapped by the shaping surfaces (31, 32, 331, 341) on both sides. In this way is calibrated the profile of the distributed area of the heald (1) overlapping into the body of the heald (1) so that the areas where the deformation pressures are greatest lie outside the heald eye (2) of the heald (1). The former (3) comprises two shaping surfaces (331, 341) that are parallel and whose length is superior to the height of the heald eye (2) of the heald (1).

Description

Heald made of strip material with distributed heald eye, method of its production, and a former for its production

Technical field

The invention relates to a heald made of strip material with distributed heald eye, the method of its production, and a former for the production.

Background art

Healds made of strip material are in general use with weaving machines. They are arranged in healdframes which, in their turn, are installed in weaving machines. In the weaving machine, the healds made of strip material are so arranged that the strip material plane is parallel with the warp threads. In the area of the heald eye, the heald made of strip material undergoes modifications intended to ensure the passage of the warp thread through the heald eye and consisting in an angular displacement of the area around the heald eye relative to the strip material plane or in alternatively distributing the arms of the heald eye.

The drawback of the healds with turned area (with angular displacement) around the central eye consists in excessive width of the heald in said area resulting in increased strain imposed on adjacent warp threads by the edges of the swivelled area.

The drawback of the healds fitted with alternately distributed heald eye consists in particular in the tendency to clamp the warp thread while carrying it.

The patent specification CZ 2620-94 (DE 4336362) discloses the heald eye of a heald made of strip material in which the plane of the heald eye area is turned relative to the plane of the other part of the heald, and the arms of the heald eye are distributed and turned back to the position parallel with the plane of the main part of the heald.

The advantage of this solution consists in the reduction of the heald width in the heald eye area with sufficient distance of the heald eye arms and good support for the warp threads in the dead centers of the healdframe. Its disadvantage consists especially in the high requirements imposed on the process of its production.

The space available for turning the heald eye arms back to the position parallel with the main flat part of the heald, defined by the heald eye length, is a limited one. For this reason, the return angular setting of the arms is made by a sharp bend almost cutting the heald which requires a very exact position of the shaping means relative to the heald eye. If during the return angular setting of the heald eye arms a deviation occurs from the correct position of the arm bend in relation to the heald eye, it may involve the danger of producing a sharp lug near the heald eye. A similar danger of almost cutting the heald is present even with the correct position of the arm bends due to the fact that the shaping means, small in radius, act heavily on the heald eye. The danger of damaging the inner wall of the heald eye is further increased by the fact that the deformation, and consequently the pressures, are greatest on the edge of the heald eye in its corners.

Another solution, described in US 5,348,055, discloses heald eye arms distributed and so shaped that the plane passing through them makes with the heald plane an angle different from zero.

The drawbacks of this solution are the same as those of the preceding one since here, as well, they relate to the deformation area of the heald eye arm.

Principle of the invention

The above drawbacks are reduced or fully eliminated by the heald made of strip material according to the invention whose principle consists in that the heald eye arms are distributed by a plane distribution in the distribution area whose length is superior to the heald eye height. Thus, the heald has a prismatic shape convenient for the passage of the carried warp thread also in the area over and under the heald eye which permits to reduce the requirements imposed on the position accuracy of the bends in relation to the heald eye in the longitudinal direction of the heald. Preferably, the width of the distribution area of each heald eye arm is superior to the width of this arm so that in a rectangular heald eye the deformation areas pass through the upper and the lower wall of the heald eye. The increased extension of the distribution area reduces the risk of pressure trace creation around the heald eye.

The solution according to the invention permits to increase the bend radii. Preferably, in the plane distribution of the arms, the inner diameter of the heald profile bends is superior, or equal, to two thirds of the size of the heald eye distribution. Consequently, the heald profile in the heald eye distribution area consists of stepless passages and is similar to the shape of the letter "S". As compared with the state of art, the pressure exerted on the heald material is inferior so that the former produces only a glossy trace on the heald surface.

Another not negligible advantage of the heald according to the invention consists in locating the section of the greatest pressures involving the risk of the heald eye deformation into the heald body outside the heald eye so that said risk of damage to, or deformation of, the inner walls of the heald eye is eliminated. The areas of the greatest pressures are located in such sections of the heald body where no carried or free neighboring warp thread can penetrate.

To reduce the strain on the material of the heald fitted with heald eye arms distributed in a plane, it is advantageous to set to less than 10° the angle α made between the distributed heald eye arms and the heald plane. The angular displacement by the angle α is technologically necessary especially with a large distribution to prevent the heald from being damaged at the heald eye area.

The principle of the method of production of the heald according to the invention consists in gripping the heald between the shaping surfaces of the former at a length superior to the heald eye height overlapped by shaping surfaces on both sides thus calibrating the profile of the distributed area of the heald overlapping into the heald body so that the areas of the greatest deformation pressures lie outside the heald eye.

The former contains two shaping surfaces for carrying out the method of production of the heald according to the invention, and its principle consists in that the two shaping surfaces of the former are parallel and surpass in length the height of the heald eye of the heald.

Preferably, the shaping surfaces of the former comprise distributing shaping surfaces of the heald eye arms whose width is superior to the width of the heald eye arms.

In order to obtain a fluent and accurate plane distribution of the heald eye arms, in particular in the area over and under the heald eye, the former is fitted with distributing shaping surfaces of the heald eye arms which are connected by means of calibration surfaces.

The inner bend radius between the distributing shaping surface and its following calibration surface can be equal or superior to the distribution size of the heald eye of the heald.

Description of the drawings

Examples of embodiment of the heald according to the invention and of the former for its production are schematically shown in the enclosed drawings in which Figs. 1 a, 1 b show the half finished product of the heald after the heald eye has been cut; Figs. 2a to 2e the sequence of the shaping operations for distributing the heald eye, and more specifically, Fig. 2a a view of the semi-finished product of the heald gripped between the shaping surfaces of the formers, Fig. 2b a section of the semifinished product of the heald according to Fig. 2a; Fig. 2c a section of the heald eye at the final stage of the plane distribution, Fig. 2d the view in the direction D of the final stage of the plane distribution according to Fig. 2c, Fig. 2e the view in the direction E of the final stage of the plane distribution according to Fig. 2c; Fig. 3a a section of the calibrating former at the beginning of the shaping, Fig. 3b a section of the calibrating former at the end of the shaping, Fig. 4a a view of the heald with the heald eye distributed in the warp thread direction, Fig. 4b a detail of the heald eye, Fig. 4c a section of the heald in the distributed area over the heald eye, Fig. 4d a section of the heald in the area of the heald eye, and Fig. 5 an axonometric view of the shaped part of the heald. Modes for carrying out the invention

A heald 1 made of strip material contains in its middle part a heald eye 2. The other parts of the heald 1 are not substantial for the invention, are made in one of t e well-known variants of embodiment and will be neither shown in drawings nor described in detail.

The heald eye 2 is made in the heald 1 as a cut hole as shown in Figs. 1a, 1b, and is defined on its side walls by arms 21, 22. On its upper side, the heald eye 2 is defined by an upper wall 23, and on its lower side, by a lower wall 24. The distance between the upper wall 23 and the lower wall 24 defines the height 25 of the heald eye 2, and the distance between the inner walls of the arms 21 , 22 defines the width 26 of the heald eye 2. The arms 21 and 22 of the heald eye 2 are distributed by a plane distribution which means that they are plane figures both before and after the distribution, as shown in Figs. 2a to 2e.

In the example of embodiment shown in Figs. 2a to 2e, the plane distribution is carried out by a pair of coupled and simultaneously operating formers 3_1, 32 out of which during the distribution process the first one 31_ grips the first arm 21 of the heald eye 2, and the second one 32 grips the second arm 22 of the heald eye 2. Fig. 2a shows a plan view of the heald 1. with a not yet distributed heald eye 2. The shaping surfaces of the two formers 31. 32 are longer than the height 25 of the heald eye 2 and at the same time wider than the width of the arms 21 , 22 of the heald eye 2, for instance by one tenth or less of the width 26 of the heald eye 2. In the first step of the plane distribution, shown in Figs. 2a, 2b, the shaping surfaces of the first former 31 come to lie on the surface of the not distributed arms 21 , 22 of the heald eye 2 of the shaping surface of the first former 31 and of the shaping surface of the second former 32 and grip them. The force 310 acting on the first former 31 and the force 320 acting on the second former 32 moves the two formers 31, 32 to their end pressing position thus causing both the plane distribution of the arms 21, 22 of the heald eye 2 and the deformation of the heald 1 in an area longer than is the height 25 of the heald eye 2, as shown in Figs. 2c, 2d, 2e. Consequently, the plane distribution of the arms 21., 22 is accompanied by the same plane distribution of the sections of the heald 1 situated over and under the heald eye 2 to a distri^¬ bution value 302. The distribution value 302 of the arms 21, 22 of the heald eye 2 is equal to the value of the overlapping of the shaping surface of the first former 3J. relative to the shaping surface of the second former 32 lying on the same side of the heald 1, in the end pressing position of the formers 3_1, 32.

Due to the increase in the size of the distribution of the arms 21, 22 of the heald eye 2, the deformation area in process of distribution of the arms 21 , 22 of the heald eye 2 is situated outside the places of contact between the inner surface of the arms 21, 22 with the upper and lower walls 23, 24 of the heald eye 2, thus eliminating the risk of cracks or changes in the shape at the corners of the heald eye 2 and/or on the inner walls of the heald eye 2.

According to a not shown example of embodiment, the shaping surfaces of the formers 3_1, 32 are of the same width as the arms 21, 22 of the heald eye 2. However, the length of the shaping surfaces of the formers 3_1, 32 is also in this embodiment superior to the height 25 of the heald eye 2.

Figs. 3a, 3b show a calibrating former 3 having a lower part 33 and an upper part 34. A lower shaping surface 331 is provided on the lower part 33, and an upper shaping surface 341 is provided on the upper part 34, of the calibrating former 3. The two shaping surfaces 331, 341 are parallel and their length is superior to the height 25 of the heald eye 2. The lower shaping surface 33 . of the calibrating former 3 consists of the lower distributing shaping surface 3311 of the first arm 21 of the heald eye 2 and of the lower distributing shaping surface 3312 of the second arm 22 of the heald eye 2 mutually connected by a lower calibrating surface 3313. The lower calibrating surface 3313 passes into the lower shaping surface 3311 of the first arm 21 by an inner radius RJ_ of a bend, and into the lower distributing shaping surface 3312 of the second arm 22 by an outer radius R2 superior in size to the inner radius Rl by the thickness of the heald To obtain an optimum quality of the distribution of the arms 21, 22 of the heald eye 2, the inner radius FM of the bend is equal or superior to two thirds of the distribution value 302 of the arms 21, 22 of the heald eye 2. Due to this, the heald profile in the area of distribution of the heald eye 2 consists of steplessly connected sections similar to the shape of the letter "S", and is easy to produce by cold pressing.

The upper shaping surface 341 of the calibrating former 3 consists of an upper distributing shaping surface 3411 of the first arm 21 of the heald eye 2 and of an upper distributing shaping surface 3412 of the second arm 22 of the heald eye 2 which are by means of the radii Rl, R2 of the bend connected with an upper calibrating surface 3413 extending between them. The distributing shaping surfaces

3411, 3412, 331. 3312 make with the heald plane an angle α inferior to 10° and chosen depending on the size of the heald eye 2, on the size of the distribution of the arms 21, 22 of the heald eye 2 as well as on other specific technological requirements. The angular displacement of the arms 21, 22 by the angle α is technologically necessary in particular if the distribution is large, because it prevents the heald from being damaged during the distribution process.

As is shown in Fig. 3b, the width of the upper and lower distributing shaping surfaces 3411 and 3311 of the first arm 21 of the heald eye 2 is superior to the width of the first arm 2J. of the heald eye 2, and the width of the upper and lower distributing shaping surfaces 3412 and 3312 of the second arm 22 of the heald eye is superior to the width of the second arm 22 of the heald eye 2. In this way, the areas D1 , D2, where the deformation pressures are greatest, are transferred outside the heald eye 2 of the heald 1, as shown in Fig. 5.

According to a not shown embodiment of the calibrating former 3, the width of the distributing shaping surfaces 3411 and 3311. 3412 and 3312 of the first and second arms 21 , 22 of the heald eye 2 is equal to the width of these arms 21 , 22 of the heald eye 2, and the length of the distributing shaping surfaces 3411, 3311 ,

3412, 3312 is superior to the height of the heald eye 2.

Claims

PATENT CLAIMS

1. A heald made of strip material with a distributed heald eye, characterized by that the arms (21 , 22) of the heald eye (2) are distributed by a plane distribution in the distribution area whose length is superior to the heald eye ( 2 ) height ( 25 ) .

2. A heald as claimed in Claim 1 , characterized by that the width of the distribution area of each heald eye (2) arm (21 , 22) is superior to the width of this arm (21 , 22).

3. A heald as claimed in Claim 1 or 2, characterized by that the inner diameters (R1 ) of the bend of the plane distribution of the arms (21 , 22) of the heald eye (2) are superior or equal to two thirds of the size (302) of the distribution of the arms (21 , 22) of the heald eye (2).

4. A heald as claimed in any of Claims 1 to 3, characterized by that the distributed arms ( 21 , 22 ) of the heald eye ( 2 ) are turned in relation to the plane of the heald (1 ) by an angle α inferior to 10°.

5. A method of production of the heald eye of a heald made of strip material as claimed in Claims 1 to 4, characterized by that the heald (1 ) is gripped between the shaping surfaces (31 , 32, 331 , 341 ) of a former (3) at a length superior to the heald eye (2) height overlapped by shaping surfaces (31 , 32, 331 , 341 ) on both sides thus calibrating the profile of the distributed area of the heald (1 ) overlapping into the heald (1 ) body so that the areas (D1 , D2) of the greatest deformation pressures lie outside the heald eye (2) of the heald (1).

6. A former containing two shaping surfaces for carrying out the method of production of the heald as claimed in Claim 1 , characterized by that the two shaping surfaces (331 , 341 ) of the former (3) are parallel and surpass in length the height of the heald eye (2) of the heald (1 ).

7. A former as claimed in Claim 6, characterized by that the shaping surfaces (331 , 341) comprise distributing shaping surfaces (3311 and 3411 , 3312 and 3322) of the heald eye (2) arms (21 , 22) whose width is superior to the width of the heald eye (2) arms (21 , 22).

8. A former as claimed in any of Claims 6 or 7, characterized by that the distributing shaping surfaces (3311 and 3411 , 3312 and 3412) of the arms (21 , 22) of the heald eye (2) are connected by means of calibrating surfaces (3313, 3413).

9. A former as claimed in Claim 8, characterized by that the inner radius (R1) of the bend between the distributing shaping surface (3312, 3411) of the arms (21 , 22) of the heald eye (2) and its adjoining calibrating surface (3313, 3413) is equal or superior to two thirds of the distribution value (302) of the heald eye (2) of the heald (1).