US1053958A - Gripper. - Google Patents

Description

S. W. WINSLOW, JR.

Patented Feb. 18, 1913.

L53 95SQ UNITED STATES PATENT OFFICE.

SIDNEY W. WINSLOW, JR., 0F BEVERLY, MASSACHUSETTS, ASSIGNOR TO UNITED SHOE MACHINERY COMPANY, OF PATERSON, NEW JERSEY, A CORPORATION OF NEW JERSEY.

GRIIPPER Patented Feb. 18, 1913.

Application filed December 14, 1910. Serial No. 597,195.

To all whom it may concern:

Be it known that. I, SIDNEY V. \VINsLow, J12. a citizen of the United States, residing at Beverly, in the county of Essex and State of Massachusetts, have invented certain Improvements in Grippers, of which the following description, in connection with the accompanying drawings, is a specification like reference characters on the drawings indicating like parts in the several figures.

This invention relates toupper stretching grippers and particularly to grippers of power-operated shoe machines, such as the pulling-over machines.

In the manufacture of shoes under present conditions the upper is thoroughly stretched in conforming it to the last and for the purpose of avoiding waste of ex pensive leather the upper is out only large enough to overlie the shoe bottom the required amount when it has been so stretched. These facts preclude the pulling-over machine which is the initial upper stretching machine from obtaining a deep grip on the upper. This is particularly the case at the sides of the shoe and it has become important to devise gripper jaws which can. with a shallow grip. seize and securely hold the upper without tearing or otherwise injuring itwhile subjecting it to the required severe stretching.

To provide grippers which will successfully meet these conditions is the object of the present invention.

lVith this and other objects in view, an important feature of this invention is found in gripper jaws that have what is herein termed ball and socket gripping formations on their upper seizing faces. These faces have substantially hemispherical projections on one jaw, which is preferably the jaw that engages the finished side of the leather, and correspondingly shaped recesses or sockets formed in the opposed jaw and arranged to have the leather forced thereinto by the projections. Such jaws are found to be peculiarly effective for holding the shoe upper without tearing or otherwise damaging it while it is being thoroughly stretched by the operation of the powerful commercial pulling-over machine which is of the type represented in United States Letters Patent No. 663,777. Preferably the projections, and of course cooperating depressions. will be spaced a substantial distance apart so as to form distinctly separate holding points along the edge of the upper with intervals between them in which the upper is gripped by the plane faces of the jaws. These local holding points may advantageously be arranged in two rows to engage along the edge of the upper and be staggered.

The projections have been referred to as hemisp ierical but they may be any spherical segment or the functional equivalent thereof. They are preferably formed as integral protuberances from the body of the jaw, but may be made as separate devices inserted in the face of the jaw, and in one embodiment 'of the invention these projections are shown as the rounded heads of pins or blocks and as backed up by screws that permit adjustment to vary the projection of the heads. hen the projections are non-integral with the body of the jaw they may be formed of a different kind of material. as for example, a material that has a greater coefficient of friction or holding power against the upper material than does the material of the jaw the primary requirement for which is strength. Hard rubber and fiberoid are holding materials of this class and T have shown one of these ma terials in an illustrated embodiment of the invention. Herein are to be seen further features of this invention and still another feature is to be found in provision for clearing the sockets. One of the practical conditions that reduces the efiiciency of grippers is that depressed portions fill more or less with particles of leather. lint, dressing and other foreign material which tend to make the gripping faces smooth. I have provided the jaw that has the recesses in its gripping face with clearance openings through from said recesses to permit the es cape of foreign material. The projections on the other jaw force the dirt into and through the clearance openings and so keep the recessed jaw clear. The clearance openings are preferably of smaller diameter than the sockets, this construction having the effect of truncating or cutting off the narrow portions of the sockets. so that gripping of the material is avoided at the points or tops of the projections, where it might become too intense when thin stock is being treated; taltes ltl place only,aboutQan; nular area or izonaryisurface of "such proje etions, the jpressurejbeing tliusjdistributetl over ,a, larger= area wand-undesirable :mark- "-ing,o f the st'oek prevented} Some of the advantages of this invention might, however,

be'obtained'if theopenin s wee substantially of-the samesize as tlie projections on the opposed jaws, this construction tending to concentrate-the gri i'pin'g-etfcct about a narrowerannular area than s tlie'case when the'opemngslfa're of'.sinaller size. In jaws made in accordancefwith this invention in' which the projections and socketsare'relatively large andtnot'numerous,.it 1s' practical to provide the clearance openings without obje ctionably weakening the jaw.

The several features of the invention \\'Ill be more fully understood from the follow ing description of an illustrative construction and thenthe invention will be more definitely pointed out in theclaims.

Figure 1 is a side elevation, partly in section, of a gripper for the )ulling-over machine of said patent and which is equipped with the present invention. Fig. 2 shows in perspective the gripping faces of the cooperating jaws. Fig. 3 is a section showing clearance openings. Fig. 4 is a section showing a construction in which the projections are non-integral with the jaw and are adjustable, the shadin indicating that the projections are of a diti'crent material from the body ofthe jaw.

The gripper mechanism as a whole is of well known commercial construction fully described in a prior United States Letters Patent No. 1,030.264, granted June 18, 1912, on application of Ronald F. McFcely. This com )rises a jaw carrier 2 on which jaw 4 is ri i ly mounted and jaw I) is pivoted at 6. ithin the jaw carrier moves longitudinally a bar 10 from which is suspended a book 12 that engages a slide 14 to pull it upwardly.

The slide has a'roll ll'i'that contacts with the upper arm of pivoted jaw 5 to rock said jaw toward the fixed jaw and by its wedging action on said upper arm to-close the jaws powerfully upon the stock. The bar 10 ms on its upper end a head 16 bywhich it is raised to close the jaws, against the downholding force of a spring '18 that rests on a shelf 3 of the jaw carrier, and is then'further' uplifted by a power actuated lever mechanism to stretch the upper. In accordance with this invention one of the jaws, which will preferably. be the jaw 5 that engagesthe outer or finished side of the upper cathferjis provided with'a series of pro ections 20. These projections are substantially I hemispherical in appearance, J although obviously they-f may forlnf less'than, a hemisphere. -In the"opposed jawl it"are formed correspondingly shaped'or counterpart socle.

aIi-

"ranged in a row along the site-to the'projections on jaw 5 and into are closed to grip the upper.

'lhe projections, and'hkewise the e )ressions, are arlower edge of the jaw, being spaced a substantial distance apart to provide plane gripping faces between them. A second row of gripping form'ations'is provided above the first row and iirstaggercd relation therewith. The sockets may have clearance openings outwardly through the-jaws as at 22-3, Fig. 3. The prejections may be formed on pins or blocks it as in Fig. 4 and be backed up and positioned .adjustably by screws .25.

In this construction the projections are formed by the rounded ends of blocks of hard rubber or it might bofibroid or other material having a high cocllicient of friction against the upper and thus adapted to hold the same frictionally. This provision of jaws presenting gripping areas of one kind of material for engaging the upper and areas of a ditlerent kind of material for engaging a lining will result in holding the upper from slippage with greater security than the lining is held. These )rojections, when made of material other than metal will be less liable than a harder material to mark the edge of the upper permanently. The. gripped area of leather need not, with this formation of jaws, however, extend deeply into the upper and no disadvantage ordinarily results even if the upper is permanently marked. The

.extent to which the blocks 24 project can be chan ed by the screws 25 and the blocks can be ac vanced to compensate for wear as may be needed.

Having ex )lained the nature of the invention and described how it may be used I claim as new and desire to secure by Letters Patent of the United Statcs:-

1. A shoe upper stretching gripper having, in combination, opposed aws and means for actuating them, Stlltl jaws having a plurality of cooperating ball and socket formations on their gripping faces.

which jaws has an otherwise plane face into which extend recesses corresponding in locatron to the pro ections of the'opposed jaw.

- points at opposite lateral sides of which 4.-A shoe upper stretching gripper having, in combination, cooperating jaws and means for actuating them, said jaws havin a row of cooperating blunt projections and recemes along their lower edges spaced va substantial dlstance apart and constituting a series of separate and distinct gripping the stock is less securely held. 1

5. A shoe upper stretching gripper having, in combination, cQo eratingjaWs and means for actuating thennone of said jaws having on its gripping face a 'p'lurality of blunt projections arranged longitudinall or the edge of the upper and the'other of w ich jaws has recesses opposed to the projections and having clearance outlets. V a

'6. A shoe upper Stretching gripper having, in combination, cooperating jaws and means for actuating them, oneof said jaws having on its gripping face a plurality of projections and the other of which jaws has counter art sockets into which thestock is Y blocks of friction material set in said. re-,- cesses, and means for adjustingsaid blocks v -jections.

plane of the gripping recesses through, the jaw.

10. A shoe upper stretching gripperhav 'ing, in combination, opposed jaws and means 'for actuating them, one of said jaws being provided with-a 'pluralityigof s h ericall rounded projections and v the ,ot er wit cooperating bottomless" recesses whereby the eter than the recesses and leading from the gripping pressure is applied to annular areas of the stock. a r I -111 A shoe upper stretching gripper-haw ing'. in' combination opposed jaws and means for actuating them, one oi said jaws being provided with; spherically rounded "projections and the" other v jaw with similarly shaped truncated recesses whereby gripping 'actionis avoided boutthe tops ofthe pro- 12. A shoe upper stretching device, having combination, opposed gripping surfaces,- said surfaces being contoured m grip the stock over a plurality of annular areasonly.

In testimony whereof I have; signed 1113? name to this specification in the'presnce of two subscribingwitnesses.

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