US2865056A

US2865056A - Textile drawing mechanism

Info

Publication number: US2865056A
Application number: US630660A
Authority: US
Inventors: Friedrich Kubler
Original assignee: SKF Kugellagerfabriken GmbH
Current assignee: SKF GmbH
Priority date: 1956-01-04
Filing date: 1956-12-26
Publication date: 1958-12-23
Anticipated expiration: 1975-12-23
Also published as: FR1168065A; BE553146A; NL97656C; GB801071A; CH347462A; DE1027570B

Description

Dec. 23, 1958 F. KUBLER 2,865,056

TEXTILE DRAWING MECHANISM 'Filed Dec. 26, 1956 s Sheets-Sheet 1 INVENTOR Dec. 23 1958 F. KUBLER TEXTILE DRAWING. MECHANISM 3 Sheets-Sheet 2 Filed Dec. 26, 1956 W W Z M, E an v m w fly,

Dec. 23, 1958 F. KUBLER TEXTILE DRAWING MECHANISM 5 Sheets-Sheet 3 Filed Dec. 26, 1956 INVENTOP xvbarl'zh a o d/er United States Patent 2,865,056 TEXTILE DRAWING MECHANISM Friedrich Kiibler, Stuttgart-Bad Cannstatt, Germany, as-

signor to SKF Kugellagerfabriken Gesellschaft mit beschrinkter Haftung, Schweinfurt, Germany, a German company Application December 26, 1956, Serial No. 630,660 Claims priority, application Germany January 4, 1956 15 Claims. (Cl. 19135) 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 suspended top rolls will be eifective 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 of the forces of the springs against the top rolls.

Devices have been provided for releasably retaining the pivoted top roll supporting arm in its operative position. In such existing devices, a catch is frequently provided on the pivoted arm and is pivoted relative to the latter for engagement with a nose or keeper on a fixed bracket forming the support for the pivoted arm to resist pivoting of the latter away from the operative position by the reaction to the spring forces weighting the top rolls. In such an arrangement, the catch is pressed against its nose or keeper by the reactions to the weighting spring forces and this pressure must be relieved before the catch can be disengaged. In order to relieve such pressure, one hand is used to displace the pivoted arm from its operative position in the direction toward the lower rolls, while the other hand manipulates the catch to clear the nose or keeper. Since the release of the catch in the above described device requires the inconvenient use of both hands, other devices have been developed wherein the catch is disengaged from the nose or keeper by spring means within the pivoted arm when the latter is pressed toward the lower rolls from its operative position. Although the manipulation required for releasing or disengaging the catch is thus simplified, it is still necessary to exert a considerable force for that purpose in overcoming the combined weighting spring forces applied to the top rolls. Moreover, these other devices for simplifying the manipulation involved in disengaging the catch employ numerous parts which occupy much of the limited space within the pivoted arm, and which have the further disadvantage of resulting in a relatively expensive device that is not particularly reliable in its operation.

Accordingly, it is an object of the present invention to provide an improved device for releasably holding the pivoted arm supporting the top rolls of a drawing mechanism in its operative position; and wherein such improved device avoids the above disadvantages of the existing devices provided for that purpose and is particularly characterized by the simplicity of its construction,

2,865,056 1C Patented Dec. 2a, was

the convenience and ease of its manipulation and the reliability of its operation.

In accordance with an aspect of this invention, an operating lever is pivotally mounted on the pivoted arm carrying the top rolls and, in turn, carries a pivoted catch that is engageable with a fixed stop, for example, on the bracket supporting the pivoted arm, the parts being arranged so that engagement of the pivoted catch with the fixed stop prevents swinging of the arm from its operative position in the direction away from the lower rolls and so that manipulation of the operating lever provides a mechanical advantage for disengaging the catch from the stop and then moving the pivoted arm to its inoperative position, or for returning the pivoted arm to its operative position and again engaging the catch with its fixed stop.

Further, in accordance with the invention, the pivoting axes of the operating lever and the catch thereon and the fixed stop engageable by the catch are arranged relative to each other, when the catch is holding the pivoted arm in its operative position, so that the reaction of the fixed stop against the catch resulting from the weighting spring forces cannot effect inadvertent disengagement of the catch from the stop.

In one embodiment of the invention, the catch on the operating lever is spring urged to disengage from the fixed stop upon suitable manipulation of the operating lever, while, in another embodiment, the catch is pivoted relative to the operating lever during manipulation of the latter by the action of a pin fixed relative to the pivoted arm and received in a curved slot formed in the catch.

Further, in a device embodying this invention, the operating lever is adapted to frictionally engage a portion of a fixed part thereby to hold the pivoted arm in the inoperative position thereof.

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 drawings forming a part hereof, and wherein:

Fig. 1 is a side elevational view of a drawing mechanism for textile machinery which embodies the present invention, and which is shown in its operative condition with an operating lever thereof partly broken away and in section;

Fig. 2 is an enlarged, fragmentary sectional view of the drawing mechanism in the operative condition of Fig. 1;

Fig. 3 is a sectional view taken along the line 3-3 of Fig. 2;

Fig. 4 is a view similar to that of Fig. 2, but with the catch for holding the mechanism in its operative condition being disengaged;

Fig. 5 is another view similar to that of Fig. 2, but with the mechanism being retained in its inoperative condition;

Fig. 6 is a longitudinal sectional view of a drawing mechanism constructed in accordance with another embodiment of the invention and shown in its operative condition; and

Fig. 7 is a view corresponding to a portion of Fig. 6, but showing the catch for holding the mechanism in its operative condition after disengagement of the catch from its related fixed stop.

Referring to the drawings in detail, and initially to Figs. 1 to 5, inclusive, thereof, it will be seen that the drawing mechanism there illustrated includes a bracket 1t) which has spaced apart side walls and a connecting wall extending along the back, bottom and the lower portion of the front edges of the side walls so that the bracket 10 opens upwardly and forwardly. The side wallsof bracket have registering openings in the lower portions thereof receiving a fixed supporting rod 11, and

the lower portion of the bracket is split radially downward from the openings receiving rod 11 so that a bolt. 12 extending through the bracket 10 across the radial:

split and a nut 13 on the bolt can clamp the bracket on the supporting rod.

An elongated arm 14 of inverted, U-shaped' crosssection has its back end portion extending into the bracket 1 10 and is pivotally mounted, ata location adjacent'th'e back end of the arm, on a bolt or pivot 15 which extends through the upper front corner portions of the side walls of bracket 10.

The arm 14 is intended to support and weight the top saddles at their free ends which receive top rolls 17,

and helical springs (not shown) are arranged between the guiding arms 16 and the underside of the top of arm 14 in order to urge the top rolls 17 downwardly relative to the latter.

The arm 14 is swingable about its pivot 15 between an operative position (Figs.- 1 and 2) and araised inoperative position (Fig. 5 and a fixed underframe 18 carries rotatable lower rolls 19 against which the top rolls 17 are urged or weighted by the above mentioned helical springs when the arm 14 is in its operative position.

In order to effect movement of the arm 14 between its operative position (Figs. land 2) and its raised inoperative position (Fig. 5), thedrawing mechanism embodying this invention is provided with an operating lever 20 which extends, through an opening in the top of arm 14 adjacent the back end of the latter and is pivotally mounted withinthe arm 14 onv a pin 21 which is spaced rearwardly from the pivot -15'of the arm 14. The lever;

20 has a relatively long handle portion at one side of its pivot pin 21, and such handle-portion isjadapted to overlie the top of arm 14 and to bear downwardly, at its front end, on the arm 14, as at 22 in Fig. 1. Preferably, at least the handle portion of lever 20 has an inverted U-shaped cross-section (Fig. 3), and the arm 14 is provided with recesses 23 in the opposite sides thereof to receivethe flanks of the handle portion of lever 20.-

A torsion spring 24 encircles the pivot pin 21 and has its opposite ends bearing against the underside of the top of lever 20 and a lateral wall 25 at the back end of arm 14, respectively, to yieldably urge the lever 20 in the direction moving the handle portion of the latter upwardly relative to arm 14, that is, in the clockwise direction relative to arm 14, as viewed in Figs. 1, 2, 4 and 5.

As seen in Fig. 2, the operatinglever 29 has a relatively short extension projecting generally downward from the pivot pin 21"arid carryinga pivot pin 26 on which an auxiliary lever or catch 27 ispivotally mounted.

A leaf spring 28 has one-end encircling the pivot pin 21' so as to be supported by the latter, while the otherend:

of spring 28 bears against a lateral projection 29 on the free end portion of catch 27 and the spring 28 is bent, intermediate its ends, over the pivot pin 26, thereby to urge the catch 27 to rock in the counterclockwise direction, as viewed in Figs. 2, 4 and 5, relative to operating lever 20.

A portion-of the back Wall of fixed bracket 10 is bent or struck inwardly, as at 31, to define an upwardly facing bearing surface 30 which forms a fixed stop for the free end of catch 27. The surface 30 is disposed so that, when the free end of catch 27 bears downwardly thereon, as in Fig. 2, the lever 20 willbe held at its. frontend 22, against the top of arm 14 to retain the: latter in its operative position where the toprolls 17 are-z weighted, by their associated springs (not shown) against the lower rolls 19.

It will be appreciated that the weighting or loading springs acting on the top rolls 17 produce a reaction between the latter and the lower rolls 19 which tends to swing the arm 14 upwardly away from its operative position, and this reaction is absorbed and resisted by the contact of catch 27 with stop 30 which also resists upward swinging of the handle portion of lever 20 away from arm 14 by the action of spring 24.

It will be seen in Fig. 2 that the

pivot pins

21 and 26 and the stop 30 are arranged relative to each other so that, with the arm 14 held in its operative position by engagement of catch 27 with stop 30, the axis of pivot pin 26-lies a small distance in back of a line extending through the axis of pivot pin 21 and the point of contact of catch 27 with stop 30. Thus, the reaction of stop 30 against the. end of catch 27 tends to turn lever 20 in the counter-clockwise direction and, thereby, merely serves to securely seat the front end 22 of lever20 against the top of arm 14. Further, the spring 28 exerts only a relatively small turning force on the catch 27 merelyto ensure the proper positioning of the end of the latter on the stop 30 during engagement of the catch, as hereinafter described in detail, and the tendency of the spring 24 to turn lever 28 in the clockwise direction, when the parts are in the positions of Fig. 2, is much smaller than the contrary tendency described above and resulting from the reaction between the end of catch 27 and the stop 30. Thus, the engagement of catch 27 with stop 30 maintains arm 14in its operative position (Figs. 1 and 2) with the top rolls 17 being spring loaded or weighted against the lower rolls 19, and disengagement of catch 27 from stop 30 is. resisted by the spring loadingor weighting of the top rolls.

When it is desired to render the described drawing mechanism inoperative, that is, to move the arm 14 upwardly to its inoperative position, the handle portion of operating lever 20 is raised away from arm 14. The initial pivoting of lever 20 in the clockwise direction, as viewed in Fig. 2, relative to arm 14, moves the axis of pivot pin 26 forwardly to the line extending between the axis of pivot pin 21 and the point of contact of catch 27 with stop 30 and thereby further depresses the army 14 against the resistance of the loading or weighting springs associated with the top rolls 17. However, the relatively long handle portion of lever 20 and the toggle arrangement of the lever 20 and catch 27 provide a large mechanical advantage so that such initial pivoting of lever 20 can be accomplished with only a small effort. As the upward movement of the handle portion of lever 20 is continued and the axis of pivot pin 26 moves in front of the line between the axis of pivot pin 21 and the point of contact of catch 27 with stop 39, the spring 28 then rocks catch 27 in the counter-clockwise direction, as viewed in Figs. 2, 4 and 5, until a projection 32 on catch 27 engages an abutment 33 on lever 20 and the end of catch 27 is then free of the stop 30 and can be disengaged or moved forwardly off the latter (Fig. 4) by the clockwise swinging of lever 20 relative to arm 14. When the catch 27 has been disengaged, the spring 24 is effective to continue the clockwiseswinging of lever 20 relative to arm 14 until the lever 20 bears against the back wall 25 of arm 14 at the edge of the opening in the top of the latter through which the lever extendsv (Fig. 4). With .the parts of the drawing mechanism in the positions of Fig. 4, the weighting or loading springs associated withthe top rollers are relaxed since the arm 14 no longer forms a fixed abutment therefor, and the top rolls rest upon the lower rolls only under the weight of the pivoted arm 14.

When it is desired to move the pivoted arm 14 to its raised inoperative position, the lever 20 is manually swungfurther :in the clockwise direction :from theposi- 14 has been moved to its raised inoperative position (Fig. so that the frictional contact between

curved portions

34 and 35 will retain the arm 14 in that raised inoperative position.

When it is desired to return the arm 14 to its operative position from the position of Fig. 5 and to again impose spring loading or weighting upon the top rolls- 17, it is only necessary to swing the lever 20 in the counter-clockwise direction by pressing downwardly on the handleportion thereof. Initially, such swinging of lever 20 removes curved portion 34 thereof out of frictional contact with curved portion 35 of bracket 10, and then lowers arm 14 while the end of catch 27 is moved onto stop or bearing surface 30 and against the adjacent back wall of bracket 10. The final downward movement of the handle portion of lever 20 effects the toggle action of catch 27 to move the axis of pivot pin 26 rearwardly beyond the line connecting the axis of pivot pin 21 with the point of contact between catch 27 and stop 30, and thereby to further depress the arm 14 so that the loading or weighting springs associated with the top rolls are compressed and urge the latter against the lower rolls.

Referring now to Figs. 6 and 7 of the drawings, it will be seen that, in the embodiment of the invention which is there illustrated, the drawing mechanism, as before, includes a bracket 10a clamped by a bolt 12a and nut 13a on a supporting rod 11a, and an arm 14a for supporting the spring loaded or weighted top rolls (not shown), with the arm 14a being pivotally mounted on a bolt 15a carried by bracket 10a. In accordance with this invention, the drawing mechanism of Figs. 6 and 7 further includes an operating lever 36 which has a forked back end portion 38 pivotally mounted on a pivot pin 37 within the arm 14a. A lever or catch 40 is pivotally mounted, at one end, on a pivot pin 39 carried by the forked end 38 of lever 36 and is provided with a longitudinal slot 41 which slidably receives a guide pin 42 fixed within the arm 14a. The free end of catch 40 has a lateral projection 43 thereon adapted to bear against a bolt 44 carried by the bracket 10:: and forming a fixed stop which is disposed above the pivoting axis of the arm 14a defined by the bolt 15a.

As seen in Fig. 6, when the arm 14a is in its operative position with the catch 40 engaging the stop 44, the lever 36 generally overlies the arm 14a and, at its front end, bears downwardly upon the top of arm 14a, while the catch 40 extends generally rearwardly from the forked end 38 of lever 36 with the axis of pivot pin 39 being disposed slightly above a straight line extending from the axis of pivot pin 37 to the point of contact of the lateral projection 43 of catch 40 with stop 44. Thus, the engagement of catch 40 with stop 44 prevents any upward swinging of arm 14a away from its operative position while the reaction of stop 44 against catch 40, as a result of the spring loading or'weighting of the top rolls, tends to turn the lever 36 in the counter-clockwise direction relative to arm 14a and thereby merely presses the front end of lever 36 more strongly against the top of arm 14a so that inadvertent disengagement of catch 4% from stop 44 is thereby avoided.

It will be noted that the mechanism of Figs. 6 and 7 further includes a flat or leaf spring. 45 which is secured at one end to the underside of the top of arm 14a, and which extends rearwardly under pivot pin 37 and then over pivot pin 39, thereby to yieldably urge the lever 36 to swing in the clockwise direction, as viewed in Figs. 6 and 7, relative to arm 1411. However, the force exerted by spring'45 to swing lever 36 in the clockwise Hired tion is not adequate to overcome the contrary force resulting from the fact that the axis of pin 39 is disposed above the line between the axis of pivot pin 37 and the point of contact of catch 40 with stop 44 when the arm 14a is in its operative position.

When it is desired to move the arm 14a to its raised, inoperative position, the lever 36 is manually pivoted in the clockwise direction, as viewed in Figs. 6 and 7, and, initially, such pivotal movement of lever 36 relative to arm 14a moves the axis of pivot pin 39 downwardly past the line from the axis of pivot pin 37 and the point of contact of catch 40.with stop 44, thereby providing a toggle action which further depresses arm 1412 against the opposition of the loading or weighting springs associated with the top rolls. As soon as the axis of pin 39 has passed the line from the axis of pin 37 to the point of contact ofcatch 40 with stop bolt 44, the spring 45 can then become effective to further swing the lever 36 relative to arm 14a until the guide pin 42 reaches the end of the slot 41 in catch 40, as in Fig. 7, to thereby limit the swinging of lever 36, in the clockwise direction, relative to arm 14a. .With the parts in the positions of Fig. 7, catch 49 is free of stop 44, and the top rolls are free of the spring loading or weighting forces and are merely subjected to the weight of arm 14a.

It will be seen that, during the above mentioned swinging of lever 36 relative to arm 14a, the pivot 39 moves downwardly relative to guide pin 42 so that the free end of catch 40 is tilted upwardly relative to stop 44 to clear the latter when the lever 36 is swung further in the clockwise direction .to raise the arm 14a to the inoperative position of the latter.

When the arm 14a is to be returned to its operativev position, the lever 36 is pressed downwardly and, by reason of the spring 45, the arm 14a follows the downward movement of lever 36 until the parts are again in the positions of Fig. 7. Further downward pressure on lever 36 causes the latter to swing in the counter-clock-' wise direction, as viewed in Fig. 7, relative to arm 14a and the guide pin 42 and slot 41 of catch 40 cooperate to ensure engagement of projection 43 of the catch with stop 44, whereupon, the toggle action occurs for further depressing arm 14a and, thereby, compressing the loading springs associated with the top rolls, until the axis of pin 39 is again above the line from the axis of pin 37 to the point of contact between catch 40 and stop 44, as in Fig. 6, and the mechanism is therefore in its operative condition.

Since the movement of the top

roll carrying arm

14 or 14a between its operative and inoperative positions only requires manipulation of

lever

20 or 36, it is apparent that only one hand is required for such manipulation and that a relatively small effort is required therefor. Further, the described devices for moving the

arm

14 or 14a between the operative and inoperative positions are of relatively simple construction and reliable in operation.

Although illustrative embodiments of the invention have been described in detail herein with reference to the accompanying drawings, by way of example, it is to be noted that the invention is not limited to those particular embodiments, and that various changes and modifications may be eifected therein without departing from the scope or spirit of the invention, except as defined in the appended claims.

What is claimed is:

1. In a drawing mechanism for textile machinery hav ing 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 and for moving the pivoted arm to and from the operative position thereof, said device comprising a lever pivoted on. said arm: and having a portionadapted to bear downwardly against the latter, a catch pivotally mounted on said'lever, a fixed stop engageable by said catch when said portion of the lever bears downwardly upon the pivoted arm with the latter in. the operative position thereof to prevent displacement of the pivoted arm away from said operative position, said catch being disengaged from said fixed stop by swinging of said lever relative to thepivoted arm in the direction moving said portion of the lever away from the pivoted arm, and; means limiting the swinging of said lever, relative to the pivoted arm in said direction so that,oafter said catch has beendisengaged from said fixed stop, continued swinging of said lever in said direction efiectsrmovement of'the pivoted arm away from its operative position.

2. 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 for releasably locking the pivoted arm in its operative position against the reaction to the spring loading of the top rolls and for moving the pivoted arm to and from the operative position thereof, said device comprising a lever pivoted on said arm and having a portion adapted to bear downwardly against the latter, a catch pivotally mounted on said lever, with the pivoting axis of said catch spaced from the pivoting axis of said lever, and a fixed stop spaced radially from the pivoting axis of said arm and engageable by said catch when said portion of the lever bears downwardly on the pivoted arm with the latter in the operative position to prevent displacement of the pivoted arm away from its operative position, said pivoting axes of the lever and catch and-the point of engagement of said catch with said stop being arranged relative to' each other so that, during initial" swinging of said lever relative to the arm in the direction moving said portion of the lever upwardly away from the arm to release the latter, said pivoting axis of the catch is moved across the line connecting said axis of the lever with said point of engagement of the catch and stop thereby to rock said catch relative to said lever and to effect disengagement of said catch from said stop for thereafter permitting swinging of said lever and pivoted' arm together in the direction moving the latter away from its operative position.

3. 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 for releasably locking the pivoted arm in its operative position against the reaction-to the spring loading of the top rolls and for moving the pivoted arm to and from the operative position thereof, said device comprising a lever pivoted on said arm and having a portion adapted to bear downwardly against the latter, a catch pivotally mounted on said lever, with the pivoting axis of said catch spaced from the pivoting axis of said lever, a fixed stop spaced radially from the pivoting axis of said arm and engageable by said catch when said portion of the lever bears downwardly on the pivoted arm with the latter in the operative position to prevent displacement of the pivoted arm away from its operative position, said pivoting axes of the lever and catch and the point of engagement of said catch with said stop being arranged relative to each other so that, during initial swinging of said lever relative to the arm in the direction moving said portion of the lever upwardly away from the arm to release the latter, said pivoting axis of thecatch is moved across the line connecting said axis of the lever with said point of engagement of the catch and stopthereby to rock said catch relative to said lever and: to ,etfectdisengagement:of said catch frornsaid stop 81 for thereafter permitting swinging'of said lever and pivoted arm together in the direction moving the latter away. from its operative position, and means limiting the swinging of said lever relative to the pivoted arm in said direction so that, after said catch has been disengaged from said stop, continued swinging of said lever. in said directioneiiects movement of the pivoted arm away from its operative position.

4. In a. drawing mechanism for textile machinery; a device as in claim 3, further comprising spring means effective to rock said catch relative to said lever following themovement of, said axis of the catch across said line, and means limiting the rocking of said catch relative to said lever by said spring means.

5. In a drawing mechanism for textile machinery; a device as in claim 3, wherein said catch has a slot therein, and said means limiting theswinging of said lever relative,

to the arm includes arguide' pin fixed relative to the pivotedv arm andslidably receivedin said slot so that, when said guide pin engages; an end of said slot, further swinging of said lever relative, to the pivoted arm is prevented and so that, duringswinging of said lever relative to the arm, saidislot'and guide pin cooperate to control the rocking of said catch relative to said lever.

6; In a drawing mechanism for textile machinery; a device as in claim 3, further comprising yieldable means urging. said lever to swing relative to the pivoted arm in said direction, and wherein said axis of the catch is disposed at the side of said line which faces in the oppositev direction when the arm-is in its operative position with said portio-n of the lever bearing downwardly thereon so that the reaction between said catch and stop to the spring loading of the top rolls produces a turning moment on saidvlever in. said opposite direction to overcome said yieldable means urging said lever in the first mentioned direction.v

7; 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 for releasably locking the pivoted arm in its operative position against the reaction to the spring loading of the top rolls and for moving the pivoted arm to and from the operative position thereof, said device comprising a lever pivoted on said arm and having a portion adapted to bear downwardly against the latter, a catch pivotally mounted on said lever, a fixed stop engageable by said catch when said portion of the lever bears downwardly upon the pivoted arm with the latter in the operative position thereof to prevent displacement of the pivoted arm away from said operative position, said catch being disengaged from said fixed stop by swinging of said lever relative to the pivoted arm in the direction moving said portion of the lever away from the pivoted arm, means limiting the swinging of said lever relative to the pivoted arm in said direction so that, after said catch has been disengaged from said fixed stop, continued swinging of said lever in said direction efiects movement of the pivoted arm away from its operative position, and fixed means frictionally engageable by said lever following swinging of the latter to an extent producing a predetermined movement of the pivoted arm away from its operative position to hold the arm against return to the operative position thereof.

8. A drawing mechanism for textile machinery comprising a fixed support, lower rolls rotatable about axes which are fixed in relation to said support, an arm pivoted adjacent one end on said support and carrying top rolls at locations between its pivoting axis and the other end of the arm and which are spring loaded in the direction downwardly from the latter, said arm being movable about said pivoting axis between an operative position, where said top rolls are spring loaded against said lower rolls, anda raised inoperative position, a lever pivoted on said arm for swinging relative to the latter about an axis which is parallel to, and spaced from, said pivoting axis of the arm, said lever having a handle portion adapted to bear downwardly on said arm at a location adjacent said other end of the latter when said lever is pivoted in one direction, a catch mounted on said lever for rocking relative to the latter about an axis spaced radially from said pivoting axis of the lever, and a fixed stop on said support at a location spaced radially from said pivoting axis of said arm and engageable by said catch when said arm is in said operative position with said handle portion bearing downwardly on said arm, while said rocking axis of the catch is disposed at the side of a line between said pivoting axis of the lever and the point of contact of said catch and stop which faces in the direction opposite to said one direction of swinging of said lever so that the reaction between said catch and stop to the spring loading of said top rolls tends to turn said lever in said one direction to prevent raising of said arm from said operative position, while swinging of said lever in said opposite direction exerts a toggle action on said catch rocking the latter relative to said lever for disengagement from said stop.

9. A drawing mechanism for textile machinery as in claim 8; wherein said arm and said handle portion of the lever have inverted U-shaped cross-sections and said arm has recesses in the sides thereof receiving the sides of said handle portion when the latter bears downwardly on the arm.

10. A drawing mechanism for textile machinery as in claim 8; wherein said arm has an Opening in the top thereof, and said lever includes a portion extending upwardly through said opening of the arm between said handle portion and said pivoting axis of the lever so that, following the swinging of said lever in said opposite direction relative to said arm for disengaging said catch, said upwardly extending portion of the lever engages the back edge of said opening to cause said arm to swing with said lever to its raised inoperative position in response to continued swinging of said lever in said opposite direction.

11. A drawing mechanism for textile machinery as in claim 10; wherein said support has a curved surface effecting frictional engagement with a curved surface of said lever when said arm reaches said raised, inoperative position, thereby to retain said arm in said inoperative position.

12. A drawing mechanism for textile machinery as in claim 8; wherein said catch has an elongated, closed end slot therein, and further comprising a guide pin fixedly carried by said arm and slidably received in said slot to control the rocking of said catch relative to said lever in response to the swinging of the latter with respect to said arm and to limit the swinging of said lever in said opposite direction relative to said arm when an end of said slot engages said guide pin to thereafter cause said arm to pivot with said lever in response to continued swinging of the latter in said opposite direction.

13. A drawing mechanism for textile machinery as in claim 8; further comprising means yieldably urging said lever to swing in said opposite direction relative to said arm but with a force that is incapable of overcoming the tendency of said lever to turn in said one direction by reason of the reaction between said catch and stop to the spring loading of the top rolls while said handle portion bears on said arm in the operative position of the latter.

14. A drawing mechanism for textile machinery as in claim 8; further comprising spring means tending to rock said catch relative to said lever in the same direction as results from said swinging of said lever in said opposite direction but with a force that is inferior to the rocking force applied to said catch as a result of said reaction between said catch and stop so that said spring means effects rocking of said catch only after swinging of said lever in said opposite direction has caused movement of said rocking axis past said line between the axis of said lever and the point of engagement of said catch and stop.

15. A drawing mechanism for textile machinery as in claim 14; wherein said catch and lever have cooperative abutments thereon which are engageable to limit the rocking of said catch relative to said lever by said spring means so that, upon the swinging of said lever relative to said arm in said one direction, said catch will again be positioned for engagement with said stop.

References Cited in the file of this patent UNITED STATES PATENTS 2,508,964 Naegli May 23, 1950 2,525,647 Burnham et al Oct. 10, 1950 2,644,988 Haythornthwaite et al. July 14, 1953 2,751,632 Dausch June 26, 1956