US2519274A

US2519274A - Device for gripping and holding a weft thread in nipper looms

Info

Publication number: US2519274A
Application number: US619522A
Authority: US
Inventors: Moessinger Albert
Original assignee: Sulzer AG
Current assignee: Sulzer AG
Priority date: 1945-08-15
Filing date: 1945-10-01
Publication date: 1950-08-15
Anticipated expiration: 1967-08-15

Description

g- 15, 1950 A. MQESSINGER 2,519,274

DEVICE FOR GRIPPING AND HOLDING A WEFT THREAD IN NIPPER LOOMS Filed Oct. 1, 1945 2 Sheets-Sheet. 1

ALBERT Mosssmezz.

[Me A ATTORNEK INVENTOR.

g- 1950 A. MOESSINGER 2,519,274

DEVICE FOR GRIPPING AND uowmc;

A WEFT THREAD IN NIPPER LOOMS 2 Sheets-Sheet 2 Filed Oct. 1, 1945 INVENTOR. ALB ERT M05551 M65112.

A TORNEY.

Patented Aug. 15, 1950 DEVICE FOR GRIPPING AND HOLDING A WEFT THREAD IN NIPPER LOOMS Albert Moessinger, Wint erthur, Switzerland, as-

signor to Sulzer Freres, Societe Anonymc, Winterthur, Switzerland Application October 1, 1945, Serial No. 619,522 In Switzerland August 15, 1945 15 Claims. (01. 139-126) The present invention relates to a device for gripping and holding a weft thread in nipper looms after insertion of the thread into the shed and before the beating up into the fabric. The invention consists in that the thread gripper is fixed movably on its operating member and held in its normal working position by yielding means.

As is known, looms with free flying shuttles are provided with a control device for the flight of the shuttle, which comes into operation and causes the 100m to come to rest if the shuttle fails to enter the shuttle box at all or at the right time. In such cases this stopping of the loom at the right time prevents the occurrence of one or more beats by the reed, which would lead to damage being done to the reed, the warp threads or the fabric.

In nipper looms with weft bobbins arranged outside the shed, the weft thread is held during the beat of the reed in known manner by edge thread grippers which must previously move into the path of the shuttle in order to grip the weft thread; there is therefore always a risk of the edge thread gripper colliding with a shuttle moving late towards the shuttle box, with the result that these parts may be damaged. In order to diminish this risk, the moving forward .of the edge thread gripper into the path of the shuttle has hitherto been set to occur later than the latest permissible entrance of the shuttle into its shuttle box. But since on the one hand .a certain time must elapse between the moment when the control device comes into operation .and the time when the loom is completely at rest, in consequence of the inertia forces of the considerable masses which are in motion, but on the other hand this movement must have stopped by the time the edge thread gripper has come into the path of the .shuttle, i. .e. into its gripping position, there .is necessarily adisadvantageous shortening of the time available for the flight of the shuttle within one pick.

7 With the device according to the invention a shortening of the time available for the flight of the shuttle is avoided and damage to the parts of this device in consequence of collision with the shuttle is prevented. .As a result the output of a loom equipped with the device according to the invention is increased.

By way of example forms of execution of the subject matter of the invention are illustrated diagrammatically in the accompanying drawing, where:

Fig. 1 shows the view of a whole loom, seen from the cloth Tbeam side.

Ill)

Figs. 2 and 3 show a first example of execution in side elevation and plan respectively, with the gripper control removed,

Fig. 4 the same example of execution with the thread gripper swung out of the normal position,

Figs. 5 and 6 a second example of execution in side elevation and front view respectively,

Fig. 7 a further example of execution in side elevation, and

Fig. 8 the same with thread gripper swung out of the normal position. v p p The loom illustrated diagrammatically in Fig. 1 has two side frames 1, '2, between which are arrangedthe cloth beam 3 with the wound-on fabric 5, the reed 28 and the heald shafts 30. Near the inner sides of the frames l and '2 a device 4 is provided at each side to grip and hold the weft thread 6, which is wound on a weft bobbin 1 located outside the shed, for instance on the side frame I. The weft thread may consist of vegetable, animal or mineral material. By means of a shuttle 8 moving along the shuttle path 9 the weft thread 6 is led through the shed, the shuttle 8 arriving in the shuttle box Ill which is arranged in the side frame 2. The control device ll supervises the entrance of the shuttle 8 into the shuttle box l0, causing the loom to be stopped in time, in case the entrance of the shuttle should be delayed or not take place at all. After the weft thread ii has been inserted into the shed the devices 4 move into the path 9 of the shuttle 8 in order to hold the thread 6 while it is being beaten up by the reed '28 into the fabric 5. Instead of arranging a device 4 on the side frame l and a device 4 on the shuttle box lll, only the one on the shuttle box f0 could be provided as being the more important. When dividing the fabric into several lengths, such a device could be arranged also between each two adjacent fabric lengths.

In the example shown in Figs. 2 to 4 the device for ipping and holding the weft thread has a thread gripper which is equipped with two arms l 2, .l 3 approximately at right angles to each other. The thread gripper l2, i3 is fixed to the operating bar l5 by means of the bearing pin M. The arm 13 is provided with a notch I6 and at its end with a stop pin .Zli. Through the notch It the spring-holding bolt H5 is fixed to the operating bar '15. On the bolt I8 is fixed the torsion spring i9, one end of which presses on the pin 2| and thus keeps the thread gripper l2, 13 in its normal working position, which is determined by the stop between notch l6 and bolt l8 and is transversely directed to the operating bar I5. The end of the thread gripper arm I2 is constructed as gripper cheek 29. Through this and through the arm I3 the guide pin I! of the gripper check 22 is passed, being movable in the direction of its length. To the pin H a spring plate 23 is fixed. Between this and the gripper cheek 29 a compression spring 24, through which the pin II passes, is inserted; this spring presses the pin I! on to a cam 25. The cam 25 is fixed to the operating bar 21 by screws 26 by means of which it can be adjusted.

In the left part of Fig. 2, the thread gripper I 2, I3 is shown in its gripping position, in which it is in the path 9 of the shuttle 8. In order to be able to grip the weft thread 6, the guide pin I! is pressed downwards by the cam 25 and the

gripping cheeks

29, 22 consequently open, so that the weft thread 6 comes between the gripper cheeks when the gripper is advanced. While the thread gripper I2, I3 with its two gripper cheeks 2!], 22 is in its outermost position, and lying in the path 9 of the shuttle, the operatin bar 2! with the cam 25 moves in the direction of the arrow 35, so that the cheeks 2U, 22 close under the action of the spring 24 and hold the weft thread 6 firmly. While the reed 28 beats the weft thread 6 into the fabric, the operating bar I5 with the thread gripper I2, I3 simultaneously moves in the direction of the arrow 35 into its right hand end position and holds the weft thread 5 firmly so that it keeps the tension received hen being inserted.

Now follows the change of shed formed by the warp threads 29. This is effected by moving the heald shafts 39. These movements are executed in accordance with the type of fabric 5 to be manufactured. On the shaft 39 are fixed the h alds 3| with the eves 32. The weft threads 29 are led through the eyes 32 and mu t therefore follow the movement of the shafts 39.

The ends of the weft thread 6 la t beaten up into the fabric 5, a e held by the ri per cheeks 2.4, 2'! (Fi 3) until the beginning of the next grinning pha e. Shortlv before the be inning of this pha e. the operatin bar 21 moves in the direction of the arro 36, o that the gri per cheeks 2'1. 22 o en. With the operatin bar I5, the o eratin bar 21 moves simultan ously in the direction of the arrow 35, so that the

rip er cheeks

20, 22 are brought into the gripping position while thev are open.

If the shuttle 8 moves late towards the shuttle box III, it may ha en. as sho n in Fi 4. that the thread rip er I2. I3 and articularl its parts 2|], 22, knock against the shuttle 8. The

gripper cheeks

29, 22 are thus held back, while the operating bar I5 must positively move still further in the direction of the arrow 35 until it comes into its left end position (Fig. 2), since the loom is still in action. The thread gripper I2, I3 then swings on the pin I4 counter-clockwise, so that its arm I3 moves upwards and gives tension to the torsion spring I9. Since the shuttle 8 has not arrived at the proper time in the shuttle box III, the control device I I (Fig. 1) comes into operation and brings the loom to rest before the reed 28 begins its working movement. In spite of the fact that the control device (Fig. 1) comes into operation. not when the shuttle 8 passes at the proper time in front of the

gripper cheeks

20, 22 advancing into the shuttle path 9, but when the shuttle 8 arrives late in the shuttle box I0, and con equently comes into operation first at a later point of time, the operating bar I5 can ca y 3 its motion to the end in the direction of the arrow 35. Since the thread gripper I2, I3 is movably fixed on the operating bar I5, the collision between the shuttle 8 and the

gripper cheeks

20, 22 cannot lead to any damage being done to these parts, since the thread gripper I2, I3 swings out elastically.

In the example of execution shown in Figs. 5 and 6, the operating bar 31 is equipped with an angular arm 38, which is provided with a stop 39. By means of the bolt 40, the thread gripper 4| is fixed rotatably to the operating rod 31. On the bolt 4!], a torsion spring 42 is arranged, whose extended end lies on the gripper 4| and presses it against the stop 39 into the normal working position, which is directed transversely to the operating bar 31. This torsion spring 42 is chosen so strong, that it overcomes the inertia forces of the thread gripper 4| caused by the motion of the operating bar 31; the gripper can swing in counter-clockwise direction and the torsion spring 42 holds it firmly on the stop 39. Through the gripper cheek 43 and the short arm 45 is passed the pin 4! of the counter cheek 44- By means of the compression spring 46, arranged in the same way as in the example of execution shown in Figs. 2 to 4, and by means of the cam 25 fixed to the operating bar 21, the pin 41 causes the opening and closing of the

gripper cheeks

43, 44 and thus frees the weft thread 6 or holds it respectively. The advantage of this thread gripper 4| consists particularly in the shortness of the arm 45, whereby a reduction is obtained in the gripping masses which are swung. If a collision occurs with the thread gripper 4| advancing into the shuttle path 9, because of the late arrival of the shuttle 8 into the shuttle box I0, this will produce only small forces of acceleration, since the mass of the thread gripper 4| set into swinging motion is small, so that the

sensitive gripper cheeks

43, 44 can be to a great extent protected from damage.

Corresponding to the example of execution shown in Figs. 7 and 8, on the foot 50 of the thread gripper 49 a gripper cheek 5|, formed as a two armed lever, is hinged by means of the pin 52 fixed on the foot 50. The gripper cheek 5| is pressed against the foot 50 by a compression spring 53 supported by a spur on the thread gripper 49. The thread gripper 49 is hinged to the operating bar 55 by means of a pin 54. The operating bar 55 is provided with an arm 56 to which the tension spring 51 is attached, the other end of which is fixed to the lever arm 58 of the thread gripper 49, so that the contact surface 59 of the lever arm 58 is pressed against the contact surface 60 of the arm 56. The operating bar 55 is carried in a guide 6| in such a way that it moves essentially in the direction of its axis 62. The amount of movement of which the operating bar is capable lies between the two extreme positions of the pin 54 shown in full and dotted lines. The shuttle 8 entering into the shuttle box ID has inserted the weft thread 6 5 into the shed.

For opening and closing the thread gripper 49, the gripper cheek 5| is actuated by means of the arm 63 of a bell crank lever, so that the control surface 64 of this arm presses against the cam 65 on the cheek 5|. The bell crank lever is pivotably supported on a pin 66 fixed to the side frame I or 2 (Fig. 1) and coupled by a second arm 61 to an operating bar 68, which is set in oscillating motion in the directions of the

arrows

59, 70, by means of mechanism not shown.

The length of the control surface 64 is --chosen insuch-a way that the cam 65 remains w'-ithin the range of this surface 64 in spite of its oscillating motion "in the directions of the arrow 69, caused by the operating bar 55.

In the normal service the nrethodoi working or the device illustrated' in'Figfi is as follows: The operating bar "55 and the thread gripper '4 9 jointed to it and held in the normal working position, make an oscillating motion in the directions of the arrows 69, T0. The tension-spring 51 is however chosen stronger than the inertia forces acting on it, -'so that the contact surfaces 59-, 60 are not separated from eachother because of these movements. The amount of movement of the operating bar 55 and of the bar- 68 in the directions of the arrows "6'9, 1 0, are chosen to suit each other and are positively connected to each other.

The left part of Fig. *7 shows the thread gripper 49 in its gripping position in which the weft thread 6 lies "between the opened gripper cheeks 5!), 5i, since the control surface 154 is still in its upper end position. Now the operating bar 68 moves in the direction of the arrow Ill, so that the spring 53 expands,

theagripper cheeks

50, 5! close and the weft thread .6is held firmly. After the thread gripper 49 has been closed in this manner, the operating bar 55 makes a motion in the direction of the arrow Hi and brings the closed thread gripper 49 together with the weft threadi into the right hand end position shown in Fig. '7.. This motion occurs approximately simultaneously with the beating up of the weft thread =6 into the fabric 5 by means of the reed 2-8 (see Figs. 1 and 3). After the shed has been changed and after a new weft thread 6 has been inserted into the shed, the operating bar 68moves in the direction of the arrow .69 and opens the gripper 5|. The

gripper cheeks

50, 5| release the ends of the weft thread 6 beaten up in the fabric, and the operating bar55'leads the thread gripper 49 in the direction of the arrow 69 again into the gripping position.

Now, if it should happen that the shuttle 8 for some reason or other does not arrive in the shuttle box It! at all, or at the right time, and is in the path of motion of the

grippers

50, 5|, the thread gripper 49 or its

parts

59, 5| will knock against the shuttle 8 as shown in Fig. 8, whilst the operating bar 55 continues its motion in the direction of the arrow 69 until it reaches its left hand end position. The thread gripper 49 turns on the pin 54 in counter-clockwise direction, so that the spring 51 is given tension. Because of the thread gripper 49 being movably fixed to the operating bar 55, the collision between the shuttle 8 and the gripper cheek 50 cannot cause any damage to these parts. Since the shuttle 8 does not enter its shuttle box Hi, the control device H (Fig. 1) comes into operation and the loom is consequently stopped. After removing the cause of disturbance, the loom can be restarted, since the thread gripper 49 is automatically brought back again by means of the tension spring 51 into its normal working position with respect to the operating bar 35.

I claim:

1. A thread gripper for looms, comprising a lever member having a clamping arm, a reciprocatingly movable operating member having an end portion swingably connected to said lever member, resilient means connected with said operating member and engaging said lever memher and forcing it into operating position, the

direction of movement iof said :ioperatmg member being substantially at a right angle to said clamping arm.

'2. A thread gripper rfor looms, comprising .a lever member having a clamping arm, areciproca'tingly movable operating member having :an end portion pivoted to said lever member and its pivot point forming the fulc'rum of said lever member, resilient means connected with said operating member and engaging said .IBVBI member andirorcing :it into operating osition, said clamping arm when in "normal operating position, extending substantially at a right angle to the direction of movement of'said operating member.

A thread gripper for looms comprising a lever member having a clampingsarm :and an extension, a substantially reciprocatingly movable operating member 'swingably connected with said lever member, resilient aneans connected to said operating member and to said lever member and forcing the :latter into operating position, the direction of movement of .said operating member being substantially at a right angle to :said clamping arm, said operating :member mailing a portion extending substantialry parallel to said extension and comprising an abutment for engaging said extension and limiting movement :of said il'ever member cinder the influence of said resilient means.

'4. A thread gripper for looms comprising a substantially reciprocatirigly rmovable operating member, thread clamp means pivoted toan 'd being swinga b'le on said member, and resilient means connected with said member :and with said means *and holding the latter in operating position. v

'5. A thread gripper for "looms comprising :a substantially 'reciprocatingly movable operating member, ;a two-arm lever member pivoted to said operating member and having a thread gripping jaw-like end portion, and having another end portion resiliently connected with said toperating member.

6. A thread gripper for looms comprising an operating member, thread gripping clamp means pivoted to said operating member, and a torsion spring connected with said member and said means and resiliently holding the latter in operating position,

7. A thread gripper for looms comprising a substantially reciprocatingly movable operating member having an arm portion, a two-arm lever member pivoted to said operating member and. having a thread gripping end portion, and having another end portion resiliently held to said arm portion.

8. A thread gripper for looms comprising an operating member having an arm portion, a twoarm lever member having thread grippin means on one arm thereof and being pivoted to said operating member, and a tension spring interconnecting said arm portion and one arm of said lever member.

9. A thread gripper for looms comprising an operating member, a lever member pivoted to said operating member and having a thread gripping end portion, and resilient means connected with said operating member and engaging said lever member between its pivot point and said end portion.

10. A thread gripper for looms comprising an operating member, thread gripping means, pivot means interconnecting said operating member and said gripping means, and a torsion spring rigidly connected with said pivot means and engaging and holding said gripping means in operating position.

11. A thread gripper for looms comprising a substantially reciprocatingly movable operating member having an arm portion, thread engaging means pivoted to said operating member, and resilient means connected With said member and said means and forcing the latter to said arm portion.

' 12. A thread gripper mechanism for looms, comprising a two-arm lever member having a thread gripper on one arm thereof, an operating member pivoted at one end to said lever member and extending at substantially right angle thereto and its pivot point forming the fulcrum of said two-arm lever, said operating member having an arm portion extending substantially at a right angle to the longitudinal axis of said operating member and having an abutment portion adapted to abut the other arm of said twoarm lever member, and spring means interconnecting said arm portion and said other arm of said lever member and forcing them together until abutment of said abutment portion and said other arm of said two-arm lever is obtained.

13. A thread gripper mechanism for looms, comprising a two-arm lever member having a thread gripper on one of its arms, a substantially reciprocatingly movable operating member pivoted at one end to said lever member and extending at a substantially right angle thereto and its pivot point forming the fulcrum of said two-arm lever member, an arm rigidly connected with said operating member and extending substantially at a right angle thereto and having an abutment portion adapted to abut the other arm of said two-arm lever member, and tension spring means interconnecting the end portion of said arm of said operating member and of said other arm of said lever member and forcing them together until abutment of said abutment portion and of said other arm of said two-arm lever member is obtained, the line of action of said spring means being substantially parallel to the direction of the reciprocating movement of said operating member.

14. A thread gripper mechanism for looms, comprising a two-arm lever member having at one end a foot portion having a thread engaging surface portion, another two-arm lever member pivoted to said foot portion and having one arm having a surface corresponding in shape to said first portion and being adapted to press the thread to be gripped to said first surface portion, a spur portion projecting from said first two-arm lever member substantially oppositely said foot portion, and a compression spring disposed between said spur portion and the other arm of said other two-arm lever member for resiliently pressing said surface portions together.

15. A thread gripper mechanism as claimed in claim 14, comprising an outside member, said other arm of said other two-arm lever member having a nose portion adapted to engage said outside member and to tip said other two-arm lever member against the action of said compression spring.

ALBERT MOESSINGER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 214,506 Hunt Apr. 22, 1879 1,027,996 Cruikshank May 28, 1912 1,564,603 Martin Dec. 8, 1925 2,134,125 Hoff Oct. 25, 1938 2,185,308 Pfarrwaller Jan. 2, 1940 2,326,863 Jennings Aug. 17, 1943 2,389,808 Moessinger Nov. 27, 1945 FOREIGN PATENTS Number Country Date 516,143 Great Britain Dec. 22, 1939