US2900675A - Dausch - Google Patents

Description

Aug. 25, 1959 E, DASCH 2,900,675

TEXTILE DRAWING MECHANISM Filed March 12, 1958 2,9%,675 Patented Aug. 25, 1959 2,900,615 rnxrnn DnAwiNG MECHANISM Ernst Daiisch, Stuttgart, Germany, 'assignor to SKF Kugellagerfabriken Gesellschaft mit beschrnkter Haftung, Schweinfurt, Germany Application March 12, 1958, Serial No. 720,859 Claims priority, application Germany March 15, 1957 8 Claims. (Cl. ISL-135) This invention relates to drawing mechanisms for textile machinery and, more particularly, is directed to improvements in devices for supporting and weighting the top rolls in such mechanisms.

In drawing mechanisms for textile spinning frames and the like, weighted top rolls cooperate with lower rolls which are rotatably supported in an underframe of the mechanism. The top rolls are individually suspended from a pivoted arm which is movable between operative and inoperative positions, and springs act between the pivoted arm `and the top rolls suspended therefrom to urge the latter toward the related lower rolls` with respect to the pivoted arm in the operative position of the latter. It is apparent that the springs acting between the pivoted arm and the individually suspendedtop rolls will be effective to weight the latter, or to press them against the related lower rolls, only so long as the pivoted arm is locked in its operative position against the reactions to the forces of the springs against the top rolls.

Although devices have been provided for releasably retaining the pivoted top roll supporting arm in its operative position, such existing devices are usually complex in construction and unreliable in operation. Thus, by way of example, one existing device for releasably retaining the pivoted top roll supporting arm in its operative position includes a lever pivotally mounted on the supporting arm and formed with a detent engageable with a spring biased latch element that is pivotally mounted on the xed support of the top roll carrying arm. When the locked top roll supporting arm is pressed downwardly from its operative position toward the lower rolls, the detent of the pivoted lever is disengaged from the latch element to permit upward swinging of the pivoted top roll supporting arm to its inoperative position. 'When the pivoted arm is subsequently moved downwardly, preliminary engagement of the latch element with the detent Vof the pivoted lever is achieved, and this preliminary engagement is further secured by an additional lever coacting with the lever carried by the top roll supporting arm, and both the first mentioned lever having a detent and the additional lever are under the influence of oppositely acting springs. The above described arrangement requires extremely accurate machining of the individual levers and precise balancing of the springs acting thereon in opposed directions in order to ensure dependable operation of the locking device. However, breakdowns or defective operation may still occur quite readily because of the entry of lint into the device or because of normal wear which occurs chiefly at the detent and at the cooperating locking surface of the latch element, so that replacement of the levers and of the latch element may be frequently required. Further, in the described existing locking device, there is a tendency for fatigue to occur in the oppositely acting springs or for such springs to break, thereby causing inoperativeness ofthe drawing mechanism by preventing locking or unlocking ofthe pivoted top roll supporting arm.

Accordingly, it is an object of the present invention vice for releasably locking the pivoted top roll supporting arm in its operative position against the reaction to the spring loading of the top rolls comprises a latch member pivotally mounted on the pivoted arm and having a nose, a locking member pivoted on the xed support of the top roll supporting arm for angular movement between first and second pivotal positions and having a keeper engageable by the nose of the latch member to prevent upward movement `of the pivoted arm from its operative position, and spring means acting on the latch member to urge the latter to a predetermined pivotal position. In the locking device embodying this invention, the keeper of the locking member is disposed in the path of the nose on the latch member when the latter is in its predetermined pivotal position and the locking member is in the first position thereof, while the keeper is located in relation to the pivoting axis of the locking member to cause the latter to move from said first position to said second position by the reaction to the spring loading of the top rolls applied by engagement of the nose with the keeper. Further, the keeper and nose are shaped to resist movement of the latch member to its predetermind spring-urged position when the locking member moves to its second position while the nose engages the keeper so that the latch member returns to its predetermined position to free the nose from the keeper and thereby release the pivoted arm for upward movement from its operative position only when the pivoted arm is iirst depressed. Further, and most important, the latch member and the locking member of a locking device embodying this invention have cooperating surfaces which are slidably engageable during upward movement of the pivoted arm from its operative position to forcibly displace the locking member from its second position to its first position where the keeper is again disposed to receive the nose of the latch member upon return of the pivoted arm to its operative position. The forcible positive movement of the locking member by the latch member upon movement of the latter with the pivoted top roll supporting arm ensures that the locking device will operate reliably and will resist breakdowns.

Further, in accordance with another aspect of the invention, the locking member may be provided with a handle portion projecting beyond the fixed support on which the top roll supporting arm is pivoted, so that the locking member may be manually displaced from its second position to its first position where the keeper is disposed to receive the nose of the latch member. Thus, the locking device may be reengaged following the unlocking thereof without requiring the upward movement of the top roll supporting arm to its inoperative position. This possibility of relooking the locking device without requiring movement of the pivoted top roll supporting arm to its raised inoperative position is of special importance because all drawing mechanisms ,of a textile spinning frame must be unlocked during' extended idle or inoperative periods in order to prevent damage to the covers of the upper rolls by reason of the pressure of the latter against the fluted or grooved surfaces of the related lower rolls in order to prevent the development of eccentricity in the surfaces of the upper rolls which would result in non-uniformity of the produced yarn.

Further, in accordance with the invention, stop members are preferably provided for engagement by the locking member in the first and second positions of the latter, thereby to limit the pivotal movement of the locking member, and the latter is also provided with means frictionally resisting the pivotal movement of the locking member so that the latter is angularly displaced only in response to the forces applied by engagement with the latch member.

The above, and other objects, features and advantages of the invention, will be apparent in the following detailed description of illustrative embodiments thereof which is to be read in connection with the accompanying drawing, forming a part hereof, and wherein:

Fig. 1 is a side elevational view, partly broken away and in section, of a locking device for releasably retaining the pivoted top roll supporting arm of a drawing mechanism in its operative position;

Fig. 2 is a vertical sectional view taken along the line II-II of Fig. l;

Fig. 3 is a longitudinal sectional view of a locking device constructed in accordance with another embodiment of the invention for retaining the pivoted top roll supporting arm of a drawing mechanism in its operative position;

Fig. 4 is a view of a portion of the structure shown in Fig. 3, but with the elements of the locking device depicted in their relative positions upon release of the locking device;

Fig. 5 is a View similar to that of Fig. 4, but showing the elements of the locking device in their relative positions following movement of the pivoted top roll supporting arm to its inoperative position; and

Fig. 6 is another view similar to that of Fig. 4, but showing the relative positions of the elements of the locking device upon reengagement thereof.

Referring to the drawing in detail, and initially to Figs. l and 2 thereof, it will be seen that the textile drawing mechanism there illustrated includes a fixed support or bracket 2 secured on a supporting rod 1 of a spinning machine or the like. The fixed support 2 includes spaced apart side members having upwardly directed legs carrylng a pin 3 extending therebetween. An arm 4 of downwardly opening U-shaped cross-section is pivotally mounted, at one end, on the pin 3, and the usual top rolls 5 are individually suspended from the pivoted arm 4 by suitable saddles (not shown) with springs (also not shown) acting between the pivoted arm 4 and the top roll 5 suspended therefrom to urge the latter toward related lower rolls 19 which are rotatably supported in an underframe of the mechanism, for example, in the manner indicated in United States Letters Patent No. 2,751,632, issued lune 26, 1956, to E. F. Dausch.

The pivoted arm 4 is enveloped, along its entire length, by a cover 6, and the pivotally supported end of arm 4 is formed with downwardly extending, laterally spaced apart legs 7 which. at their lower ends, carry a pin 8.

A latch member'9 is pivotally mounted on the pin S for rockable movement about an axis extending parallel to the pivoting axis of arm 4, and the latch member 9 is formed as a bell crank or two-armed lever having arms 9 and 9" extending substantially at right angles to each other. The downwardly extending legs 7 of pivoted arm 4 also carry a pin 10 on which a spring 11 is supported. The spring 11 has two depending resilient legs disposed at opposite sides of a pin 12 carried by the legs 7 of pivoted ann 4, and the arm 9' of the latch member is embraced by the free ends of the legs of spring 11 so that the latch member 9 is urged by the spring 11 to a predetermined pivotal position at which the legs of the spring 11 are equally stressed.

The free end of arm 9" of latch member 9 is formed with a nose or contact section 30 which is engageable with a keeper or contact surface 13 formed on a locking member 15. The locking member 15 is pivotally supported, approximately at its center, on a pin 14 which extends between, and is carried by, the side members of fixed support 2.

The locking member 15 is formed of a plurality of similarly shaped, interconnected plates, as is apparent in Fig. 2, and is rockable about pin 14 between pivotal positions shown in broken and full lines, respectively, on Fig. l, and hereinafter referred to as the first and second pivotal positions of the locking member.

The locking member 15 is further formed with an arcuate abutment surface 16 which is slidably engageable by a surface 9a on the latch member 9 so that, when vthe latch member is moved bodily with the pivoted arm 4 in response to upward movement of the latter from lts operative position (shown in full lines on Fig. 1) to a raised inoperative position (shown in broken lines on Fig. 1), the engagement of surface 9a with surface 16 causes rocking of locking member 15 from its second position (shown in full lines on Fig. 1) to its first position (shown in broken lines on Fig. 1).

Preferably, iixed stops 17 are carried by the support 2 at opposite sides of the rocking axis of locking member 15 and are engageable by the latter in order to limit the pivotal or rocking movement of the locking member at the above mentioned iirst and second positions thereof. Further, the locking member 15 preferably has `an extension at one end defining a handle portion 18 which projects beyond the support 2 in order to permit manual actuation of the locking member 15 from the full line position of Fig. l to the broken line position of the same view.

As is apparent in Fig. 2, a helical spring 20 is provided on pin 14 at one side of locking member 15 in order to urge the latter axially against a member 21 which is also supported on pin 14 and which is formed of a material having a high coeicient of friction, for example, rubber Iand the like, so that the locking member will be frictionally held against inadvertent pivoting on the pin 14 and must be forcibly moved between the two positions of the locking member illustrated in Fig. 1.

The keeper 13 of locking member 15 and the nose 30 of latch member 9 are shaped and arranged so that, with the locking member 15 in the full-line position of Fig. 1 and with the latch member in the predetermined position established by the spring 11, the keeper 13 will be out of the path of movement of the nose 30', thereby to free the pivoted arm 4 for upward movement from its operative position to a raised inoperative position. However, the keeper 13 and nose 30' are both shaped so that, if the nose 30' is engaged with the keeper 13 at the time when the locking member 15 is moved to the full-line position of Fig. 1, the nose 30' will be retained in the keeper 13 while the latch member 9 is rocked about its pivot 8 against the force of the spring 11 to the position shown in full line in Fig. 1, where the latch member is angularly displaced in the counterclockwise direction from the predetermined position established by the spring 11. Further, the keeper 13 and the nose 30 are shaped and disposed on the locking member and latch member, respectively, so that, with the locking member 15 in the broken line position of Fig. 1 and with the latch member 9 in the predetermined position established by the spring 11, and wherein the legs of the spring 11 are equally stressed, the nose 30' will engage in the keeper 13 to lock the pivoted arm 4 against upward movement from its operative position.

Assuming that the various parts of the above described locking device embodying the present invention are initially in the positions shown in full line on Fig. 1, such locking device operates as follows:

The pivoted top roll supporting arm 4 is initially depressed or moved downwardly from its operative position so that the pin 8 supporting latch member 9 moves toward the right, thereby to withdraw nose 30 from keeper 13 and to permit the spring 11 to angularly return the latch member to its predetermined position, that is, in the counterclockwise direction as viewed in Fig. 1, so that the keeper 13 no longer extends into the path of movement of nose 30. Thereupon, the pivoted arm 4 is free to be moved upwardly about pin 3 to its raised inoperative position, `as shown in broken line on Fig. 1. During such upward movement of arm 4 from its operative position to its inoperative position, the surface 9a of latch 9 rides along the surface 16 of locking member and thereby forcibly rocks the locking member 15 from the full line position of Fig. 1 to the broken line position of Fig. 1. Thus, when the pivoted arm 4 is returned downwardly from its inoperative position, the keeper 13 of locking member 15 is already disposed for engagement by the nose 30 of latch member 9 with the latter being disposed in its predetermined position by the action of spring 11. Upon release of the downward force exerted on pivoted arm 4 in order to eifect the return of the latter from its inoperative position, the. reaction to the forces of the springs (not shown) weighting the top rolls 5 tends to swing pivoted arm 4 upwardly, and this reaction causes a slight angular movement of latch member 9 to the position shown in full lines on Fig. l, whereby spring 11 is tensioned and locking member 15 is angularly displaced from its broken line position to the full line position of Fig. l, as established by the stops 17. Thus, the described locking device is again conditioned for release upon subsequent depressing of the pivoted arm 4 from its operative position.

Although the locking member 15 has been described above as being moved from its full line position to its broken line position where it is again engageable by the nose 30 of latch member 9 in response to upward movement of pivoted arm 4 to its raised inoperative position, relooking of the locking device can be achieved without such movement of the pivoted arm 4 to its fully raised inoperative position. Thus, after release of the locking device, the handle portion 18 of locking member 15 may be manually actuated to move the locking member to its broken line position on Fig. 1, whereupon a downward force applied to pivoted arm 4 will again cause nose 30 of latch member 9 to be engaged in keeper 13 of the locking member.

Referring now to Fig. 3 of the drawing, it will be 'seen that the locking device there illustrated for retaining the pivoted top roll supporting arm 4 in its operative position with respect to the fixed support 2 includes a latch member 23 in the form of a pawl pivoted on a pin 22 carried by arm 4 and urged to a predetermined position, shown in Fig. 4, by a leaf spring 24 which is anchored, at one end, to the pivoted arm 4 and extends, at its other end, into a slot provided in the latch member 23. The locking device of Fig. 3 further includes a locking member 25 which is pivotally mounted approximately at its center on a pin 28 carried by the fixed support 2.

The locking member 25 is formed with a downwardly facing shoulder or keeper 27 which is engageable by a nose 30 on the latch member 23 (Figs. 3 and 6) in order to lock pivoted arm 4 against upward swinging about its pivot pin 3 from the operative position of the arm 4 illustrated in Fig. 3.

The locking member 25 is capable of pivotal movement between a rst position (Figs. 5 and 6) where the keeper 27 is disposed in the path of movement of the nose 30 of latch lmember 23 to receive the nose 30 with the latch member in the predetermined position established by the spring 24, as in Fig. 6, and a second position (Figs. 3 and 4) where the keeper 27 is spaced from the nose 3l) of the latch member 23, with the latter in its predetermined position established by spring 24, as in Fig. 4, thereby to free the pivoted top roll supporting arm 4 for upward movement to its inoperative position.

Further, the xed support 2 preferably carries two stops 29 which are alternately engageable by locking member 25 in order to establish the two dilerent terminal positions of the locking member, as in Figs. 4 and 6, respectively.

6 Although the keeper or shoulder 27 is clear of the nosel 30 of latch member 23 when the locking member 25 is in the position of Fig. 4 and the latch member 23 is in the predetermined pivotal position established by the spring 24, it will be noted that the keeper 27 and nose 36 are so shaped as to retain the nose in engagement with the keeper when such engagement is initiated with the locking member 25 in the position of Fig. 6 and the locking member is thereafter rocked to the position of Fig. 3, so that the latch member 23 is slightly pivoted about pin 22 from` the predetermined position established by spring 24.

Further, the latch member 23 and locking member 25 are formed with surfaces 23a and 26, respectively, 'which are slidably engageable, as in Fig. 5, during bodily movement of the latch member in response to upward swinging of supporting arm 4 from its operative position, as in Fig. 3, to a raised inoperative position, thereby to cause movement of locking member 25 from the position illustrated in Figs. 3 and 4 to the position illustrated in Figs. 5 and 6.

The locking member 25 of the device illustrated in Figs. 3 to 6, inclusive, is also preferably frictionally held against inadvertent or free rocking between the two positions thereof illustrated in Figs. 4 and 5, respectively. In order to provide such frictional resistance to free rocking of locking member 25, the latter may be formed with a substantially U-shaped cross-section so that the locking member has resilient sides or anks yieldably bearing against the adjacent side members of the support 2 and thereby ensuring that the locking member will be yieldably held in any position thereof and can be displaced from such position only in response to the application of a positive force.

Assuming that the locking device of Figs. 3 to 6, inclusive, is initially in the locked condition of Fig. -3. for retaining top roll supporting arm 4 in its operative position, the locking 4device then operates as follows:

When pivoted arm 4 is pressed downwardly from its operative position, nose 30 of latch member 23 is released from keeper 27 of locking member 25 thereby to permit spring 24 to angularly return the latch member to its preestablished position, wherein nose 30 clears keeper 27, as in Fig. 4, to permit upward movement of the latch member with pivoted arm 4. During upward movement of pivoted arm 4 to its raised inoperative position, surface 23a of the latch member rides against surface 26 of locking member 25 thereby to angularly displace the latter from the position of Fig. 4 to the position of Fig. 5.

Thus, the locking member 25 is automatically disposed in its position (Figs. 5 and 6) for receiving the nose 30 or" latch member 23 in the keeper 27 of the locking member upon subsequent downward movement of pivoted ann 4 to its operative position, as in Fig. 6.

Upon release of the downward force applied to pivoted arm 4 to effect the return of the latter to its operative position, the reaction to the spring forces waiting the top rolls carried -by arm 4 causes latch member 23 to rock in the clockwise direction, a's viewed in Fig. 6, and such slight rocking of the latch member flexes the spring 24 and returns the locking member 25 to the position of Fig. 3 wherein the locking member is again disposed to release the nose 30 from keeper 27 upon a subsequent depression of the pivoted arm 4.

It is apparent that the locking member 25 may be provided with a handle portion (not shown) projecting beyond the fixed support 2 in order to permit manual actuation of the locking member from the position of Figs. 3 and 4 to the position of Figs. 5 and 6 so that pivoted arm 4 may be relocked in its operative position without first moving such pivoted arm to its raised inoperative position for effecting automatic movement of locking member 25 to the position of Figs. 5 and 6.

It will be apparent that, in each of the above described embodiments of the invention, the locking member or is positively and forcibly actuated between the two described positions thereof, thereby to ensure long continued and reliable operation of the locking device.

Although illustrative embodiments of the invention have been described in detail herein with reference to the accompanying drawing, it is to be understood that the invention is not limited to those precise embodiments, and that various changes and modifications may be effected therein without departing from the scope or spirit of the invention, except as defined in the appended claims.

What is claimed is:

l. ln a drawing mechanism for textile machinery having a fixed support, an arm pivoted on the support and carrying top rolls which are spring loaded against lower rolls in an operative position of the pivoted arm; a device for releasably locking the pivoted arm in its operative position against the reaction to the spring loading of the top rolls, said device comprising a latch member pivotally mounted on the pivoted arm and having a nose, a locking member pivoted on the fixed support for angular movement between first and second pivotal positions and having a keeper engageable by said nose of the latch member to prevent upward movement of the pivoted arm from its operative position, and spring means acting on said latch member to urge the latter to a predetermined pivotal position, said keeper being disposed in the path of said nose when said latch member is in said predetermined pivotal position and said locking member is in said first position, said keeper being located in relation to the pivoting axis of said locking member to cause the latter to move from said first position to said second position by the reaction to the spring loading of the top rolls applied by engagement of said nose with said keeper, said keeper and nose being shaped to resist movement of said latch member to said predetermined position when said locking member moves to said second position while said nose engages said keeper so that said latch member returns to said predetermined position to free said nose from said keeper and thereby release said pivoted arm for upward movement from its operative position only when the pivoted arm is first depressed, and said latch member and locking member further having cooperating surfaces which are slidably engageable during upward movement of the pivoted arm from its operative position to forcibly displace said locking member from said second position to said first position where said keeper is again disposed to receive said nose upon return of the pivoted arm to its operative position.

2. ln a drawing mechanism for textile machinery having a xed support, an arm pivoted on the support and carrying top rolls which are spring loaded against lower rolls in an operative position of the pivoted arm; a device as in claim l, wherein said locking member has a I Cal carrying top rolls which are spring loaded against lower rolls in an operative position of the pivoted arm; a device as in claim l, further comprising stop members carried by the fixed support and engageable by said locking member to limit the pivotal movement of the latter to the angular range between said first and second positions.

4. In a drawing mechanism for textile machinery having a fixed support, an arm pivoted on the support and carrying top rolls which are spring loaded against lower rolls in an operative position of the pivoted arm; a device as in claim l, further comprising means frictionally resisting pivotal movement of said locking member between said first and second positions thereof so that said locking member tends to remain in any position to which it is forcibly moved.

5. In a drawing mechanism for textile machinery having a fixed support, an arm pivoted on the support and carrying top rolls which are spring loaded against lower rolls in an operative position of the pivoted arm; a device as in claim 4, wherein said means frictionally resisting pivotal movement of said locking member includes a braking member of friction material engageable with said locking member, and spring means urging the latter in the direction of its pivoting axis against said braking member.

6. In a drawing mechanism for textile machinery having a fixed support, an arm pivoted on the support and carrying top rolls which are spring loaded against lower rolls in an operative position of the pivoted arm; a device as in claim 4, wherein said means frictionally resisting pivotal movement of said locking member includes resilient side portions on the latter pressing laterally outward against adjacent surfaces of the fixed support to frictionally resist pivotal movement of the locking member.

7. In a drawing mechanism for textile machinery having a xed support, an arm pivoted on the support and carrying top rolls which are spring loaded against lower rolls in an operative position of the pivoted arm; a device as in claim l, wherein said latch member has an arm projecting radially therefrom, and said spring means includes a generally U-shaped spring member carried by the pivoted arm and embracing said arm projecting radially from the latch member.

8. In a drawing mechanism for textile machinery having a xed support, an arm pivoted on the support and carrying top rolls which are spring loaded against lower rolls in an operative position ofthe pivoted arm; a device as in claim 1, wherein said latch member has a radial slot therein, and said spring means includes a leaf spring member anchored, at one end, on the pivoted arm and engaging, at its other end, in said radial slot of the latch member.

References Cited in the file of this patent UNITED STATES PATENTS 2,688,162 Balmes Solanas Sept. 7, 1954 2,777,169 Noguera Jan. 15, 1957 2,787,025 Balmes Solanas Apr. 2, 1957

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