US2365654A

US2365654A - Traverse mechanism for card stripping apparatus

Info

Publication number: US2365654A
Application number: US501758A
Authority: US
Inventors: Charles E White
Original assignee: Abington Textile Machinery Works Inc
Current assignee: Abington Textile Machinery Works Inc
Priority date: 1943-09-10
Filing date: 1943-09-10
Publication date: 1944-12-19
Anticipated expiration: 1961-12-19

Description

. TRAVERSE MECHANISM FOR Dec. 19, 1944. wm 2,365,654

CARD APPARATUS Filed Sepjt. 10,

on the screw along its the disengagement of the parts at the end of the Patented Dec. 19, 1944 TRAVERSE MECH'ANISM FOR CABD STRIPPING APPARAT US Charles E. White, Abington,

Abington Textile Machinery Mass., a trust of Massachusetts Mass., assignor to Works, Boston,

Application September 1-0, 1943, Serial No. 501,758 6 Ciainis. (CL 19-109) The present invention is concerned with improvements in the traverse mechanism of card stripping apparatus. li 1 In pneumatic card stripping apparatus of the general type shown in the United States patent to Clark, No. 1,614,103,- the suction nozzles are mounted on a nozz1e' carriagewhich is given a traversing movement by a rotating lead screw, the carriage during stripping being connected with the traverse screw by a pawl or dog, the nose of which runs in the thread of the screw. Because of the proximity of fly during the operation of the machine, it is not possible to use oil to lubricate the parts. The friction is therefore considerable and the wear of the parts relatively rapid.

Furthermore,at the end of each traverse, it is necessaryrto disengage the pawl from the screw, which is done automatically by an abutment into which the pawl runs to knock-out the latter from the screw. This forcible disengagement tends in time to chip the screw m the zone where disengagement takes place; so that y frequently, in making repairs, it isnecessaryto replace the entire screw along with the pawl.

I t is the object of the present invention to improve the driving connections between the traverse screw and nozzle carriage of pneumatic card stripping apparatus by providing rolling engagement in place of sliding contact between the parts. More specifically, the invention contemplates the provision of a roller pawl of novel design, which not only substantially reduces wear length, but also permits traverse to take place smoothly and without damage to thepthreads of the screw.

i These objects have been attained by providing in accordance with the invention a pawl inthe form of a roller, the periphery of which runs in the thread of the traverse screw. The roller is of cup-shaped contour to permit engagement with the screw at a substantial of roller axis to the axis of the screw, in order that the iorces to which the bearing of the roller is subjected may be largely radial. This angular relationship of roller and screw axes is actually a compound V angle, based as will hereafter appear on; flare angles of the roller and on angles of inclination and tilt of the roller axis so that after the roller has been placed in engagement with the screw at the beginning of a traverse, the parts are automatically maintained in freely rolling engagement without the use of looking devices or other retaining means. At the end of the traverse, the

pawl may readily be rolled out of engagement without injury to the screw;

In the drawing illustrating the invention, Fig. 1 is a view of a portion of the traverse screw of Vacuum card strpping mechanism of the same general type as shown in the Clark patent above referred too, with a portion of the nozzle carriage shown in section and illustrating the roller pawl in operative engagement with the thread of the screw; Fig. 2 is a sectional view of the parts shown in Fig. 1, taken on the line of said figure; and Fig. 3 is a sectional view, taken on the line 33 of Fig. l.

Thetraverse screw, indicated at 8, is of conventional design for Vacuum stripping mechanisms. A pitch angle of 915 is indicated, although the roller pawl to be described may be employed with traverse screws having a greater or lesser pitch angle as desired or required. The traverse screw runs within a traverse tube H! fixed in the machine frame; the tube providing a support for the nozzle carriage, a portion of which is.indicated at I2. The sleeve is slotted along its length to provide access for the pawl.

The roller pawl l4 is of cup-shaped contour, and is so mounted that the thread of the screw is -engaged bythe outer edge |6 of the flaring rim. The roller is pivotally mounted on a pawl lever l8 by means of a shouldered rivet 20. The pawl lever is pivotally connected to the nozzle carriage 12 by a pin 22 to enable the roller pawl to be moved into and out of engagement with the traverse screw.

In describing the various angular relationships of the parts by which the objects of the invention are achieved, it is convenient to define the several angles which are involved. The first of these angles is the flare of the roller, being the angle between the outer wall of the roller and the center line or axis; Let such angle be termed A, as indicated on the drawing. A suitable value for this angle has been found to be in the .dicated in Fig. 1 as angle B, is chosen in relation to the angle of flare of the roller so that the sum of the two angles is somewhat greater than 90-. Thus, with an angle of approximately between axes of screw and roller, as indicated, a 15 difference results. This angle, represented by C in Fig. 1, insures that the engagement between screw and roller will take place between the rounded outer rim portion of the roller and the base of the screw thread.

pivotally mounted on the Due to the relatively large (60) angle between axes of screw and roller, a substantial proportion of the forces transmitted by the screw to the roller in driving the nozzle carriage is directed radially of the roller with a relatively small component of force in an axial direction at one point of the rim. Since this latter component tends to{skew the roller on its: pivot, it is desirable that this component be as small as practical in view of the rapid wear which results with bearings of limited length To insure, once the roller pawl has been placed in engagement with the screw, that the parts will automatically remain in driving engagement throughout the traverse without the use of locking devices, the roller is tilted at an angle which is hereinafter referred to as a run-in angle. This angle, indicated at D in Fig. 3, is the angle between the plane of rotation of the roller pawl and a tangent to the screw at the point of contact between the screw and roller. This angle need not be more than a few degrees,. an angle of approximately 5 having been found satisfactory. The tilt of the roller must be: in a direction toward that portion of the screw rotating toward the roller, to drive the nozzle carriage in the direction indicated by arrow 24.

While this run-in angle insures that the roller will automatically remain in engagement With the screw once the traverse has been started, no

difficulties are involved in disengaging the parts at the end of the stroke. As the limit of the traverse is approached, the handle 26 of the pawl lever engagesz the sloping face 28 of an abutment carried by the machine frame. Further advance of the carriage results in swinging the lever in a direction to disengage the roller, the latter being l rolled-out of the screw smoothly and without subjecting the screw to increased wear in this zone.

While certain angles have been indicated for the flare of the roller pawl and the inclination of the axes of traverse screw and roller, these particular angles are not in themselves extremely critical. It is, however, important that the sum of the fiare angle and the inclination angle be somewhat greater than 90, in order that the en gagement between screw and roller be With the outer rim of the roller. By making the angle between axes of roller and screw of the order of 60, adequate clearance may be provided 1'0r the roller, yet the forces at its bearing are predominantly radial, so that undue wear on the bearing is avoided These interrelated angles, together with the runin angle, engage the screw in rolling result that operation for long made possible without repair contact, with the periods of time is or replacement of the parts.

Iclaim as my invention:

1. A driving connection for the traverse motion of card stripping appa.ratus comprising, in combination with the nozzle carriage, a roller pawl carriage for rolling engagement with the traverse scre said pawl being cup-shaped to provide a fiaring rim portion, the axis of the pawl being inclined to the axis of the screw to provide engagement between the thread of the screw and the Outer rim portion of the pawl, said axis of the pawl also being tilted in non-intersecting relation to the axis of the screw enable the pawl to to provide run-in between the pawl and the screw.

2. A driving connection for the traverse motion of card stripping apparatus comprising, in combination with the nozzle carriage, a roller pawl pivotally mounted on the carriage for rolling engagement with the traverse screw, said pawl being cup-shapd to provide a flaring rim portion, the axis of the roller pawl being inclined to the axis of the screw and the plane of rotation of the roller pawl being inclined relativeto a tangent to the screw at the point of contact of screw and pawl.

3. A driving connection for the traverse motion of card stripping apparatus comprising, in combination With the nozzle carriage, a. roller pawl pivotally mounted on the carriage for rolling engagement with. the traverse screw, said pawl being cup-shaped to provide a rim portion fiaring outwardly from the axis at an angle of approximately 40, and. the axis of the roller pawl being inclined to the axis of the screw at an angle of approximately 60.

4. A driving connection for the traverse motion of card stripping apparatus comprising, in com bination With the nozzle carriage, a roller pawl pivotally mounted on the carriage: for rolling engagement with the traverse screw, said pawl being cup-shaped and having a ,rim portion flaring outwardly from the axis of the roller at an angle thereto, andthe axis of the roller being disposed at an angle to the axis of the screw, the sum of said angles being greater than to enable the outer portion of the rim of the pawl to engage the thread of the screw.

5. A driving connection for the traverse motion of card stripping apparatus comprising, in com-' and roller, said angle of tilt being of the order of 5 and in a direction toward that portion of the screw rotating toward the roller to provide relative run-in between the matically maintain. the roller pawl in engagement with the screw.

6. Traverse mechanism for pneumatic stripping apparatus of cards, comprising in combina-tion, a traverse screw, a nozzle carriage, a pawl lever, and a, roller pawl carried by said lever, the pawl consisting of a. cup-shaped member pivotally mounted on said lever and positioned to engage the screw with the axis of the pawl inclined at an angle of approximately 60 to the axis of the screw, said roller having an outwardly fiaring rim portion inclined at an angle of approximately 40 to the axis of the roller, the plane of rotation of the roller being tilted at an angle of approximately 5 with respect to a tangent to the screw at the point of contact between roller and screw, the tilt being towards the screw relative tothat portion thereof rotating towards the roller.

' CHARLES E. WHITE.

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