US2287275A - Trimming machine - Google Patents

Description

June 23, 1942. w. 'r. a. ROBERTS 2,287,275

v wnmmme MACHINE Filed Jan. 28, 1941 s Sheets-Sheet 1 June 23, 19.42. w. ROBERTS 2,287,275

TRIMMING MACHINE Filed Jan. 28, 1941 5 Sheets-Sheet 2 June 23; 1942. w, T, ROBERTS 2,287,275

TRIMMING MACHINE Filed Jan. 28,1941 5 Sheets-Sheet 3 Patented June 23, 1942 TRIMll/IING MACHINE William Thomas Buckingham Roberts, Leicester, England, assignor to United Shoe Machinery Corporation, Borough of Flemington, N. J., a corporation of New Jersey Application January 28, 1941, Serial No. 370,307- In Great Britain February 29, 1940 4 Claims. (Cl. 12-835) This invention relates to machines for trimming surplus material from the lasting margins of partially fabricated shoes and, more particularly, to the type of trimming machine illustrated in British Letters Patent No. 530,981, and in'my application for Letters Patent of the United States Serial No. 338,723, filed June 4, 1940, and granted as Patent No. 2,260,483, on Oct. 28, 1941.

A machine of the type under consideration is designed to sever surplus material from the lasting margin of the vamp ofa McKay shoe prior to the lasting of such margin but after the shoe has been partially fabricated on a last. Such a shoe may be side-lasted and its toe margin may have been pulled over prior to this trimming operation. Under these circumstances, the tack customarily driven at the toe end in the pullingover operation forms two ears of the toe margin, which ears usually include a layer of stiffening material (toe-box) and distort the portion of the vamp that envelops the toe of the last. from the last instead of conforming closely thereto.

To obtain uniform and satisfactory results from the trimming operation with which this invention is concerned, the bulging formations above referred to should be eliminated and the vamp should be conformed to the toe of the last when the trimming operation is initiated.

With the foregoing purpose in view, the present invention provides an improved combination comprising, in addition to the several mechanisms heretofore provided, a supplemental mechanism arranged to wipe the vamp heightwise of the last and to eliminate any bulging formations that may have been developed prior to severing the surplus material from the vamp.

A novel feature of this wiping mechanism is embodied in the work-engaging element thereof.

This element is U-shaped and is arranged to embrace the toe portion of a shoe and to travel between that portion and the wall of a U-shaped recess in a cutting bed against which the toe of the shoe is stressed with sufficient force to render the wiping movement effective. The wall of this recess is thus utilized first to develop clamping pressure of the vamp against the toe of the last and thereafter to guide and brace the wiping element.

The invention also provides a novel combination of power-operated mechanisms organized to perform their respective functions according to a predetermined sequence and to derive their operative motions from a common source of rotation These ears cause the vamp to bulge away under manual control. The timing of the several mechanisms in this combination produces the following results: one train of mechanism clamps the shoe endwise with pressure against the wall of the U-shaped recess in the cutting bed; another train of mechanism wipes the vamp heightwise of the last while the shoe is so clamped; still another train of mechanism thereafter spreads the lasting margin of the vamp on another surface of the cutting bed; and finally, a cutting mechanism severs the surplus material of the margin 0 spread on the cutting bed. All these operations are performed automatically without manual intervention except that required to initiate the first of them.

Referring to the drawings:

Fig. 1 is a right side elevation, partly in section, of a trimming machine embodying the invention, the general outline of the machine cor-- responding to a former development being represented in broken lines;

Fig. 2 is a vertical section, partly in elevation, of an assemblage in which a partially fabricated shoe to be trimmed is secured in the desired position for the trimming operation;

'Fig. 2A represents a portion of the cutting bed in section and a wiping element at the upper limit of its range of wiping movement;

Fig. 3 is a top plan view of the U-shaped wiping element included in Figs. 1 and 2;

Fig. 4 is a sectional view of the structure intersected by the line IVIV of Fig. 2; and

Fig. 5 is a front elevation, partly in section, including the wiping mechanism, the cutting bed,

the elements for spreading the lasting margin on the cutting bed, and portions of the machine frame.

Referring first to Fig. 2, the shoe I0 represented therein is partially fabricated on a last I I. This is a shoe of the McKay type in which the upper is side-lasted with tacks l2 driven through the lasting margin, through the insole l3, and clenched against a metal plate on the bottom of the last. To prepare such a shoe for the trimming operation to which this invention is related, the operator pulls out the tack usually driven at the toe end in the pulling-over operation to secure the lasting margin 14 temporarily to the insole. The lasting margin, being thus released, may spring up as represented in solid lines, but, if it doe not spring up, it may be raised manually.

Since the general organization of the machine herein illustrated and described is the same as that more fully disclosed in my former application, Serial No. 338,723, it will suffice for the present purposes to describe only briefly those elements common to both disclosures. The frame of the machine is indicated at Hi. It provides support for a stationary cutting bed comprising two relatively adjustable blocks [6, l6 (Fig. 5) on the upper surface of which the lasting margin I4 is to be spread in the manner represented by dotted lines in Fig. 2. These blocks are so formed as to provide a U-shaped recess (in plan View) for the reception of the toe portion of a shoe and they are So fitted one into the other as to provide an uninterrupted work-supporting surface and, at the same time, to provide for relative angular adjustment whereby the effective width of the U-shaped recess may be regulated according to the widths of the shoes to be trimmed. The blocks I6 are seated upon supporting blocks I1, I! also formed to provide a U- shaped recess and capable of corresponding angular adjustment to regulate its width. A thin flexible U-shaped steel strip I8 is interposed between confronting surfaces of the blocks l6 and 11. This strip stands on edge, its upper edge projecting slightly above the work-supporting surfaces of the blocks l6 and lying in the cutting plane of a trimming knife 20 to provide a shearing edge with which the knife may cooperate to sever surplus material of the margin [4. The lower edge of the strip 18 is seated upon a series of adjustable supporting screws l9 threaded in the blocks l1 and arranged to provide means by which the upper edge may be located in true shearing relation to the cutter. As the blocks l6 and I! are adjusted to regulate the width of the U-shaped recess, the curvature of the strip [8 will partake of such adjustment.

The knife 20, although circular, does not rotate, but is operated with movement of translation in the direction of the arrow in Fig. 2, and its leading edge is thereby carried across the cutting-bed and beyond the shearing strip l8. Thus, with one stroke in a straight path, the knife skives the margin l4 to a thin edge and severs all portions of the margin that extend beyond the strip I8. At the conclusion of its cutting stroke the knife is returned to its initial position, represented in Fig. 2, where it remains until the machine is again set in operation by tripping a clutch of a starting-and-stopping mechanism.

Referring to Fig. 1, the-knife is aflixed to a carrier 2| arranged to slide in guides on the frame I5. Its to-and-fro motions are derived from an eccentric 22 aifixed to a power-operated camshaft 23. The train of connections for communicating motion to the carrier 2| comprises an eccentric strap 24, a lever 25 having two upstanding arms in duplex relation, and two connecting rods 26 each connecting one arm with the carrier 2|. The lower end of the lever '25 is mounted on. a stationary fulcrum rod 21, and the camshaft 23 is journaled in bearings 28'provided by the frame. (See Fig. 5).

Other elements common to the machine disclosed in the aforesaid application, Serial No. 338,723, include a pair of fingers 3|], 30 so arranged and operated by automatic mechanism as to spread the lasting margin l4 on the cutting bed and to press it firmly against the latter in advance of the knife 20. These spreading fingers are carried by -a member 3| to which they are connected by individual pivot pins 32 that enable them to swing toward and from each other. Up-and-down motions are imparted to the carrier 3| in addition to motions parallel with the path of the knife 20. The spreading fingers stand initially in the positions represented in Figs. 2 and 5 but when the automatic operation of the machine is initiated they execute the following motions: First, a motion'toward the knife of a length sufficient to carry them beyond the lasting margin l4; angular motion about their pivot pins 32 whereby their front ends are moved toward each other to bring them within the bounds of the lasting margin; a downward movement by which their lower edges are brought nearly, if not quite, to the insole I3; a movement of translation away from the heel end of the shoe to place their butt ends in register with the cutting bed, and at the same time, a spreading movement of their tip ends; a dwell in the movement of translation occurs at this stage, during which the fingers are depressed slightly to compact the outspread margin I4 against the cutting bed; next, upward movement by which the fingers are raised out of contact with the outspread margin; and further movement of translation away from the heel end of the shoe to clear the path of travel of the knife 20; and, finally, a return movement to their initial positions. All these movements of the fingers 30 are derived from power-operated mechanisms including cams (not shown) aifixed to the camshaft 23.

To locate a shoe in the desired position for the trimming operation, the forepart of the shoe bottom is placed in contact with the lower surfaces of two stationary gages 35 and 36. The forepart may be supported firmly against these gages by a roll 31 mounted in the upper end of a post 38. The latter is connected to a treadle (not shown) by which it may be raised. Moreover, a clamping member 40 is arranged to be brought against the heel end of the shoe with movement toward the cutting bed. The member is effective to force the toe end of the shoe against the upright surface of the cutting bed that forms the boundary of the U-shaped recess therein. The initial movement for operating the member 40 is derived from a hand lever 4|, Fig. 1, arranged to swing on a fulcrum rod 42. This movement of the lever 4| is communicated by a compression spring 66 to a carrier 43 and ;thereby to the clamping member 40.

Rotation for driving the camshaft 23 is communicated thereto by gears 44 and 41 and is derived from a shaft 45 to which the driven member of a clutch is afiixed. The driving member of this clutch includes a pulley 46 that is intended to be rotated continuously by a belt. A starting-and-stopping mechanism for controlling this clutch is, or may be, the same as the corresponding controlling mechanism described in the aforesaid application, Serial No. 338,723.

Moreover, all the other elements hereinbefore described are, or may be, like the corresponding elements in the former application above mentioned.

The improvements that constitute the novel subject matter of the present invention will now be described. A U-shaped wiping element comprising two sections 50, 50 (Fig. 3) is arranged to move heightwise of the shoe in the U-shaped recesses in the blocks l6 and H. The workengaging portions of the members 50 are thin plates of steel having rounded upper edges but the lower portions thereof are provided with hinge formations and these are connected by a hinge-pin 51. The upright meeting edges of the work-engaging portions are formed one with a convex cylindrical surface and the other with a concave cylindrical surface and one is nested in the other to form a flush joint 49 (see Figs. 3 and 5). The axis of these cylindrical surfaces coincides with the axis of the hinge-pin 51. A deflected spring 52 is attached to pins 53, 53 affixed respectively to the sections 50. The eifect of this spring is to spread the sections 50 and maintain them in contact with the recess-forming surfaces of the blocks I1.

The lower surfaces of the sections 50 lie in a common plane (see Fig. 5) and are seated upon a fiat supporting surface of a carrier 54. The hinge-pin 5! extends through this carrier and the wiping element is thereby connected to the carrier with provision for angular movement of the sections 50 corresponding to angular adjustments of the blocks 16 and IT. The lower end of the carrier 54 is connected to a block 55 by a horizontal pivot pin 56. This pivotal connection provides for swinging the carrier 54 and the wiping element forwardly and downwardly out of the U-shaped recess in the blocks I1, and thus facilitat-es access to the adjusting screws l9 and to other elements in their vicinity that may sometimes require adjusting or cleaning.

Although the inclination and the force of gravity of the wiping assemblage tend to swing the wiping element away from the blocks ll, this tendency is counteracted by duplicate spring followers 51 arranged in sockets in the block 55. Each of these followers comprises a moderately stifl compression spring and a plunger, the latter being arranged to abut one of two flat surfaces 58 formed on the carrier 54. The combined forces of the followers are sufficient to maintain the wiping element in contact with the blocks IT, as shown in Fig. 2, but the followers will yield to permit the wiping element to be swung downwardly about the pivot pin 56.

Wiping motion is derived from a cam 66 (Fig. l) afixed to the power-operated shaft 23 and is communicated therefrom by a lever 6!, a link 62, and the block 55 to the carrier 54. The lever 6| is mounted on the fulcrum rod 42 and is provided with a roll 63 that engages the cam. The up-and-down movements of the block 55 are guided by a pair of arms 64 through which the shaft 23 extends to provide bearings for them. The forward ends of the arms 64 are rigidly secured to the block 55 by screws 65. The force of gravity of the wiping element and of the parts for communicating motion to it is sufficient to maintain the roll 63 in contact with the periphery of the cam 60.

Assuming that the wiping mechanism stands in its initial position, as represented in Figs. 1, 2, and 5, the shoe may be stressed against the cutting bed by operating the clamping member 40 through the medium of the hand lever 4|. This lever is also an element of a starting mechanism by which rotation of the clutch member 46 is utilized to produce rotation of the camshaft 23. The starting motion of this lever is the one that operates the clamping member 40, but the applied force of the latter against the shoe is automatically increased by a cam 61 (Fig. 1) carried by the shaft 23 to compress the spring 66.

The wiping mechanism performs its wiping function before the spreading fingers 30 reach that point in their paths of movement where they spread the lasting margin on the upper surface of the cutting bed. The wiping element starts to rise immediately and the automatic compression of the spring 66 starts when rotation of the shaft 23 is initiated. At this stage, the upper of the shoe is initially in contact with the wall of the U-shaped recess in the cutting bed but the shoe is forced away slightly by the upper edge of the wiping element which rises to a plane about flush with the upper surface of the cutting bed. The shoe does not rise because the bottom of the forepart is maintained in the desired plane by the stationary gages 35 and 36. The member 40 and the spring 66 both yield to permit the lengthwise displacement of the shoe in response to the demand of the wiping element.

If, prior to upward movement of the Wiping element, the upper of the shoe is not closely conformed to the toe of the last, the wiping element will remove any wrinkles or slack that may exist and will come to rest when its upper edge is about flush with the upper surface of the cutting bed. It will arrive at this position in time to provide a fulcrum over which the lasting margin M will be bent by the spreading fingers 30. The force by which the shoe is then stressed against the wiping element by the member 40 and the compressed spring 66 is sufficient to support the wiping element until the member 4|] releases the shoe at the conclusion of the cycle of automatic motions even though, in the meantime, the cam 6i] (Fig. 1) will have moved out of contact with the cam roll 63. Then, when the shoe is released, it will release the Wiping element and permit the force of gravity to return the latter to its initial position. I

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. A trimming machine comprising a cutting bed having a U-shaped recess to receive the toe end of a partially fabricated shoe on a last, shoeclamping means arranged to secure the forepart of the shoe in said recess, an articulated U-shaped wiping element arranged to travel heightwise of the last between the toe of the shoe and said surface of said recess, said wiping element comprising a series of connected and relatively movable parts, resilient means arranged to maintain said parts in contact with said surface, mechanism arranged to impart heightwise wiping movement to said Wiping element, spreading means arranged to lay the toe margin of the shoe on said cutting bed, and cutting mechanism arranged to sever surplus material from the margin spread on said cutting bed.

2. A trimming machine comprising a cutting bed having a U-shaped recess to receive the toe end of a partially fabricated shoe on a last, means arranged to secure the forepart of a shoe in said recess, wiping mechanism including a U-shaped wiping element arranged to travel heightwise of the last between the shoe and the surface of said cutting bed by which said recess is bounded, spreading means arranged to lay the toe margin of the upper on said cutting bed, and trimming mechanism including a cutter arranged to cooperate with said cutting bed to sever surplus material from said margin.

3. In a trimming machine of the type in which a cutter and a cutting bed having a U-shaped recess are cooperatively related to sever surplus lasting material from the outspread toe margin of the upper of a partially fabricated shoe on a last of which the toe is nested in said recess; means arranged to maintain the shoe in cooperative relation to said cutting bed, a U-shaped Wiping element comprising relatively adjustable portions arranged to embrace toes of different widths, said wiping element being formed and arranged to travel heightwise in said recess of the cutting bed, power-operated mechanism arranged to thrust said wiping element between the shoe and said cutting bed, and power-operated mechanism arranged to operate said cutter with movement across said wiping element and said cutting bed.

4. A trimming machine comprising a cutting bed having a U-shaped recess to receive the toe end of a partially fabricated shoe on a last,

means arranged to secure the forepart of a shoe in said recess, power-operated wiping mechanism including a U-shaped wiping element arranged to travel heightwise of the last between the shoe and the surface of said cutting bed by which said recess is bounded, spreading means arranged to lay the toe margin of the shoe on said cutting bed, and power-operated trimming mechanism including a cutter arranged to cooperate with said cutting bed to sever surplus material from said margin.

WILLIAM THOMAS BUCKINGHAM ROBERTS.

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