US3149648A

US3149648A - Weaving looms

Info

Publication number: US3149648A
Application number: US260485A
Authority: US
Inventors: Laithwaite Eric Roberts
Original assignee: Nat Res Dev
Current assignee: National Research Development Corp UK
Priority date: 1961-10-23
Filing date: 1963-02-25
Publication date: 1964-09-22
Anticipated expiration: 1981-09-22

Description

Sept. 22, 1964 R. LAITHWAITE 3,149,648

,WEAVING LOOMS Original Filed Oct. 23, 1961 2 Sheets-Sheet 1 v INVENTOR: ERIC ROBERTS LAITHWAITE.

Sept. 22, 1964 E. 4R. LAITHWAITE WEAVING LOOMS 2 Sheets-Sheet 2 Original Filed Oct. 25, 1961 INVENTOR: ERIC ROBERTS LAITHWAITE.

United States Patent 3,149,648 WEAVING LOOMS Eric Roberts Laithwaite, Cheadle, England, assignor to National Research Development Corporation, London, England, a British corporation Original application Oct. 23, 1961, Ser. No. 147,006. Divided and this application Feb. 25, 1963, Ser. No. 260,485 Claims priority, application Great Britain Oct. 27, 1960 3 Claims. (Cl. 139-55) This application is divided from copending application Serial No. 147,006 filed October 23, 1961.

The present invention relates to weaving looms and is more particularly concerned with improvements which enable a more constant tension to be maintained in the warp threads during the weaving operation.

It is well known that the tension in the warp threads varies considerably in a conventional loom during the opening and closing of the shed. This variation in tension is very undesirable and it is the object of the present invention to provide arrangements whereby the variation in tension is substantially eliminated.

According to a feature of the invention, in a weaving loom having arrangements for oppositely separating the warp threads to form a shed, the sley and the reed are maintained in a fixed position relative to the frame of the loom and cam-controlled means are effective to move the warp threads and the cloth relative to the reed to effect the beat-up operation, said cam-controlled means also being effective during the formation of the shed in ensuring that the tension in the warp threads is substantially the same as it was prior to the shedding operation.

According to another feature of the invention, in a combined reed and healds, the reed is maintained stationary with respect to the frame of the loom and consists of a plurality of members shaped to define a dent between any two of them and a plurality of sliding members each having supporting surfaces for a warp thread and each movably mounted within one dent, means being provided for controlling the movement of the sliding members in the slots to form a shed.

The invention will be better understood from the following description of a number of embodiments which should be taken in conjunction with the accompanying drawings comprising FIGS. 1 to 6.

In the drawings;

FIG. 1 shows diagrammatically one embodiment for obtaining constant warp thread tension,

FIGS. 2 and 3 show diagrammatically another embodiment,

FIG. 4 shows a combined reed and healds,

FIGS. 5A, 5B and 5C show details of the sliding member forming the healds, and

FIG. 6 shows the details of one of the plates forming the reed.

Referring first to FIG. 1, warp threads 61 and 62 are taken ofi a warp beam 63 and passed through

heald frames

64 and 65 and

second heald frames

66 and 67 respectively. The warp threads 61 and 62 are held in relatively fixed locations in the

heald frames

64, 65 and 66, 67 in conventional manner and are free for vertical displacement in one or the other of the heald frames of each set. Upon leaving the

second heald frames

66 and 67, the warp threads 61 and 62 pass through a reed 68 and across the sley 69 to a take-up roller 70.

In operation,

heald frames

66 and 67, reed 68, sley 69 and take-up roller 70 operate in a conventional manner, the raising and lowering of the

heald frames

66, 67 being effected under the control of

earns

71, 72 mounted on the loom camshaft 73. The

heald frames

64 and 65 are displaced at the same time as the

heald frames

66 and 67 under the control of

cams

74, 75 also mounted on the loom camshaft 73. However, the displacement of the

heald frames

64 and 65 is related to that of

heald frames

66 and 67 thereby causing a second separation of the warp threads to maintain a uniform tension in each thread. Consider a single warp thread such as 61 extending from point A on the warp beam 63 to the cloth on point D of the sley 69, this thread passing through an eyelet in heald frame 64, freely through frame 65, through an eyelet in frame 66 and freely through frame 67. A warp thread, such as 62, passes freely through the frame 64, through an eyelet in frame 65, freely through the frame 66 and through an eyelet in the frame 67. In the position shown in FIG. 1, both warp threads are tensioned and the heald frames are so arranged that the path AB+BC+CD followed by the thread 61 is equal to the path AE-l-EF-i-FG +GD by the thread 62. During shed changing

frames

64 and 66 will be lowered and

frames

65 and 67 will be raised so that thread 62 will take up a position substantially that shown in FIG. 1 for thread 61 and vice versa. Further the path followed by the two threads in the heald frames is such that during shed changing the distance between points A and D measured along the threads remains constant and hence the threads are under the same tension during shed changing.

The invention is not limited in its application to looms of conventional type but may be applied to looms where shed formation is not dependent on the provision of healds. Thus in the embodiment illustrated in FIGS. 2 and 3, the shed is formed by

cams

81 and 82, each Warp thread being engaged by the periphery of one of said cams. The tension in the warp thread is maintained constant by passing the threads under an additional pair of

cams

83 and 84, each thread engaging the periphery of one of said cams. The

cams

81 and 82 are secured to the shaft and the

cams

83 and 84 to the shaft 86. The

shafts

85 and 86 rotate at constant and uniform speeds and thereby the cam arrangement ensures that the threads are of constant length between the points A and D for all positions of the

cams

81 and 82 so that the tension in the threads is maintained substantially uniform. FIGS. 2 and 3 show the positions of the two pairs of cams in the formation of different sheds, the path A B C D and the path A B C D having the same length in the two drawings.

Referring now to FIGS. 4, 5 and 6, these show a combined reed and healds. A short section of the combined reed and healds is shown in FIG. 4 and consists of a plurality of similar members 200 each of which has the shape shown in FIG. 6. Referring to this drawing, each member consists of a fiat plate 201 having on one surface four equal raised

portions

202, 203, 204 and 205, one at each corner. When two such plates are mounted face-toface with the raised portions on one engaging the flat surface of the other as in FIG. 4, it will be seen that the separation between the raised

portions

202 and 204 and between 203 and 205 defines a slot which forms one dent in the reed.

The healds are formed by a plurality of sliding members 206 (FIG. 4) one of which is shown in detail in FIGS. 5A, 5B and 50. Each sliding member consists of a flat portion 207 having a cut-out which provides two

projections

208, 209, the tips of which face one another and are spaced apart by substantially the same distance as the diameter of the aperture in the conventional wire healds. The flat potrion has two rearwardly extending

lips

210, 211 along each edge, the distance between the facing edges of the two lips being substantially equal to the width of the plate 201 (FIG. 6). In addition the thickness of the flat portion is substantially equal to the height of the raised portions 202-205 (FIG. 6). Operating

members

212, 213 extend upwardly and downwardly of the flat portion and are each provided with lugs 214,

215, the lugs being provided on opposite sides of adjacent Sliding members as shown in FIG. 4. The sliding members 206 may be secured to heald frames, for instance, by means of wires passing through holes in the

lugs

214, 215 and in the arrangement shown in the drawing two heald frames would be used to give a plain weave. However, for pattern weaving, the operating members may be controlled in the required combinations byselector mechanism of known type.

I claim:

1. A combined reed and healds comprising a plurality of reed members, means securing said members together to define a plurality of dents between adjacent pairs of said reed members, and a plurality of slidable members each having engaging surfaces for a warp thread, each of said slidable members being movably mounted within one of said plurality of debts to form a shed.

2. A combined reed and healds as claimed in claim 1, wherein said reed members each comprise a flat plate having a projecting portion at each corner of one surface,

the height of the projecting portions being equal to the required width of a dent.

3. A combined reed and heald as claimed in claim 2, wherein said slidable members each comprise a body portion and top and bottom stem portions, the stem portions lying between the projecting portions at the top and bottom of the associated reed member and the body portion incorporating the engaging surfaces and being flanged 12o engage with the side edges of the associated reed mem- References Cited in the file of this patent UNITED STATES PATENTS 521,656 Johanson June 19, 1894 869,892 Gay Nov. 5, 1907 2,457,852 Tiefenthal Jan. 4, 1949 2,480,064 Walker Aug. 23, 1949 FOREIGN PATENTS 1,436 Great Britain of 1901 760,419 Great Britain Oct. 31, 1956

Claims

1. A COMBINED REED AND HEALDS COMPRISING A PLURALITY OF REED MEMBERS, MEANS SECURING SAID MEMBERS TOGETHER TO DEFINE A PLURALITY OF DENTS BETWEEN ADJACENT PAIRS OF SAID REED MEMBERS, AND A PLURALITY OF SLIDABLE MEMBERS EACH HAVING ENGAGING SURFACES FOR A WARP THREAD, EACH OF SAID SLIDABLE MEMBERS BEING MOVABLY MOUNTED WITHIN ONE OF SAID PLURALITY OF DENTS TO FORM A SHED.