US2974333A - Inseam trimming machines - Google Patents

Description

-Juni March 14, 1961y 2,974,333

H. A. IMHOF ET AL INSEAM TRIMMING MACHINES Filed March 14, 1958 4 Sheets-Sheet 1 i hors Herman A. Imhof Joseph C. Cantley By their Attorney March 14, 1961 H. A. IMHoF ErAL INsEAM TRIMMING MACHINES 4 Sheets-Sheet 2 Filed March 14, 1958 March 14, 1961 H. A. lMHoF ETAL 2,974,333

INSEAM TRIMMING MACHINES Filed March 14, 1958 4 Sheets-Sheet 3 March 14, 1961 H. A. IMHoF Erm. l 2,974,333

INSEAM TRIMMING MACHINES Filed March 14, 1958 4 Sheets-Sheet 4 FORCE COMPONENT TENDING TO TURN SHOE FORCE COMPONENT INSEAM TRn/IMING MACHINES Filed Mar. 14, 1958, Ser. No. 721,586

Claims. (Cl. 12-4.4)

This invention relates to shoe machinery and more particularly to machines for trimming the inseams of partially fabricated welt shoes. An object of the invention is to provide an inseam trimming machine wherein the parts are so arranged as to eliminate or reduce the tendeney of a shoe to twist in the hands of an operator during the trimming op eration.

It has been found that the common undesirable tendency of a shoe to twist in the hands of an operator during inseam trimming is attributable to a component of the feeding force imparted by the inclined feed wheel acting normal to the direction of feed and toward the operator.

A force opposing the twisting component is the force applied by the cutter, be it either a conventional cupshaped knife or the newer type rotary chopper cutter, as it makes its cut in a direction normal to the direction of feed but away from the operator. This force is employed, in accordance with a feature of the invention, to oppose or counteract the undesirable twisting force by positioning its fulcrum so as toy produce an opposing torque. Since its fulcrum is the pivot edge of the welt crease guide, by spacing the axis of the welt crease guide from the axis of the feed wheel, measured in the direction of feed, or by positioning the cutter in advance of the welt crease guide, the desired counteracting torque may be obtained Without changing the operating characteristics of the machine or by adding an additional structure to impair vision or accessibility.

The above and other features of the invention, including various details of construction and novel combinations of parts, will best be understood from a consideration of the following specification taken in conjunction with the accompanying drawings in which,

Fig. 1 is a side elevation, partly in section, on a reduced scale of the head of an inseam trimming machine embodying the principles of the present invention;

Fig. 2 is a front elevation, partly in section, of the portion of the machine shown in Fig. 1;

Fig. 3 is a section of a welted shoe taken on its widest part during inseam trimming and showing the feeding and trimming instrumentalities of the machine;

Fig. 3a is a section of a welted shoe taken at its widest part prior to inseam trimming illustrating the condition known as strapping;

Fig. 4 is a front elevation, partly in section, of the trimming cutter and including a shoe being trimmed;

Fig. 5 is a diagrammatical plan view of the feeding and trimming forces acting on a shoe while it is being trimmed;

Fig. 6 is a plan view of the feeding and trimming in-v tes Patent O "ice strumentalities of the machine including a shoe being fed and trimmed; and v Fig. 7 is a front elevation on an enlarged scale of a portion of the feeding instrumentalities shown in Fig. 6.

The construction of the inseam of the usual welted shoe is illustrated in Figs. 3, 3a and 6. Fig. 6 represents the bottom of a partially fabricated shoe on a last as trimming takes place, the inseam extending upward away from the insole. Figs. 3 and 3a show sections through the shoe and last taken at the ball line, i.e. at the widest part of the shoe, Fig. 3a before trimming and Fig. 3 during trimming. The following elements are included: a last 2, an insole 4, a welt 6, a preformed insole rib 8, a lining 10, an upper leather 12, and a line of stitches 14 that form the actual inseam joint. To sever the excess portion of the sewn inseam extending above the stitch line, the shoe being held bottom upward, there is provided a rotary trimming cutter 20 which is of multi-blade construction and will be described in more detail hereinafter. The cutter is mounted for rotation by a substantially horizontal shaft 22 (Fig. 4) journaled in bearings 24 and 26 and is driven by a motor, not shown, through a belt 28 passing around a pulley 30 fixed to the cutter shaft 22.

Cooperating with the rotary cutter 20 to feed and trim the shoe are a driven feed wheel 34 (Fig. 3), which is also a rotary shearing member, a welt crease guide 36 and a rib guide 38 in addition to a depth gage 40 all mounted adjacent the lower edge or cutting point of the rotary cutter 20. The welt crease guide 36 is shaped and mounted on the machine to enter the crease between the grain side or the upper engaging surface of the welt 6 and the upper leather 12 to press the welt against the feed Wheel 34 yand also to restrict lateral movement of the shoe inwardly of the machine, ie., to the right as seen in Fig. 3. The feed wheel 34 has a conical periphery provided with radial ridges 42 engageable with the ilesh side or outsole attaching surface of the welt opposite the Welt crease guide. Formed on each of the ridges 42 is a projection or tooth 44 the function of whichv will be described in more detail hereinafter. The rib guide 38 is engageable with the inner surface of the insole rib 8 and with the bottom of the insole 4 in the channel area. Also contacting the bottom of the insole is the depth gage 40. The above-mentioned elements comprising the trimming and feeding mechanism will be described in more detail hereinafter and their cooperation explained more fully.

The rib guide 38 and its supporting mechanism will now be described with particular reference to Figs. 1 and 3. The guide is herein shown as an inverted frustum of a cone having its apex rounded, although it may be of other conventional design. It is mounted on a bracket 46 which is secured for heightwise adjustment by a slot and screw connection 48 on a pivotal bracket 50. The depth gage 40 is also mounted by slot and screw connections 52 for heightwise adjustment on `the bracket 50. The bracket 50 is pivotally mounted on a fulerum stud 54 in a forked bracket 56 iixed to the machine frame 58. Also pivoted on the fulcrum stud 54 is a lever extension 60. Passing through the upper end 62 (Fig. 2) of the bracket 50 and the lever extension 60 is a spring-biased pin 64 which, when in the position shown in Fig. 2, locks the bracket 50 and the lever extension 60 together lso that they may -pivot as a unit about the fulcrum stud 54. When the spring-biased pin 64 is withdrawn from the upper portion 62 of the bracket 50, the bracket, and consequently the rib guide 38 and the depth gage 40, may be pivoted upwardly, independent of the lever extension 60, to the left in a counterclockwise direction, as viewed in Fig. 1, to gain access to the trimming cutter and to the other trimming and feeding instrumentalities.

The welt crease guide 36, best seen in Fig. 3, comprises an idler wheel shaped to enter the crease between the grain side or upper engaging surface of thewelt and the upper of the shoe. rlhe wheel is mounted for rotation about an axis A on a stud 66 by means of ball bearings 68. 'Ihe stud 66 is xed in a projection 70 on a collar 72 loosely surrounding a bearing sleeve in which is jonrnaled a shaft 74 which mounts the feed wheel 34 for rotation about an axis B. r[he lower end of the collar 72 engages a forked bracket 76 (Fig. 1) having arms 78 which pass one on each side of the shaft 74. Extending outwardly from the collar 72 and between the arms 78 are a pair of parallel plates 80. A block 82 ts between the plates 80 inwardly of the arms 78. A shaft 84 pivoted in the arms 78 passes loosely through the block 82. The bracket 76 is secured by screws 86 to a bifurcated bell crank 88 which is pivotally mounted on the main drive shaft 90 of the machine. A worm 92 -is keyed to the shaft 90 between the arms of the bell crank 88 the function of which will appear hereinafter. When the bracket 76 is pivoted about the shaft 90, by means now to be described, the shaft 84 will move in an arcuate path and the collar 72 will move along the axis B of the shaft 74. There will at this time be relative sliding movement between the block 82 and the plates 80 and pivotal movement relative to the arms 78 of the bracket 76. rIhe bell crank 88 includes an arm 94 which extends upwardly and is urged to the right or in a clockwise direction about the shaft 90, as viewed in Fig. l, by a spring 96 which is stretched between a pin 98 on the zum 94 and an eye bolt 100 adjustably secured in the machine frame 58. Clockwise movement of the arm 94 and consequently of the bell crank 88 is limited by a stop screw 102 also adjustably threaded in the machine frame 58. By this mechanism the welt crease guide 36 is urged upwardly along the axis of the shaft '74 toward the feed wheel 34 to press the welt against the feed wheel whereby the welt is gripped between them. The uppermost position of the welt crease guide is determined by the position of the adjustable stop screw 102.

To release the welt crease guide 36 from its gripping position after a shoe is trimmed and in order to insert another shoe, the operator depresses a treadle 104 (Fig. 1) which lis connected to ya treadle rod 106 extending vertically through the frame ofthe machine. The upper end of the treadle rod 106 is pivot-ally attached to a lever 108 the opposite end of which is secured by a set screw 110 to a shaft 112 journaled in a fulcrum block 114 fixed to the upper portion of the machine frame 58. Fixed to and extending downwardly from the shaft 112 is a lever 116 having a roller 118 journaled in its lower end. Also fixed to but extending upwardly from the shaft 112 is a second lever 120 having a forked upper end 121. Passing through the fork of the lever 120 is a rod 122, the opposite end of which is pivotally journaled in a pair of forked arms 124 formed at the upper end of the lever extension 60. A spring 126 is compressed between a plate 128 on the rod 122 and an abutment 130 secured to the fulcrum block 114. The compressive force of the spring 126 is adjusted by a nut 129 on the rod 122. To insert a shoe in the machine an operator depresses the treadle 104 which through the above-mentioned mechanism pulls the rod 122 to the right, as seen in Fig. 1, against the force of the spring 126 causing the lever extension 60 and the bracket 50 to pivot in a clockwise direction about the fulcrum stud S4 thereby causing the rib guide 38 and the depth gage 40 to move in a clockwise direction away from the feed wheel 34. Continued downward movement of the treadle 104 causes the lever 116 to pivot the lever 94 in a counterclockwise direction about the main shaft thereby drawing the collar 72 and consequently the welt crease guide 36 downwardly away from the feed wheel 34 whereby the welt of the shoe may be placed between the feed wheel and welt crease guide as seen in Fig. 3.

Release of the treadle 104 permits the springs 126 and 96 to move the rib guide 38 and the welt crease guide 36, respectively, into the positions shown in Fig. 3. It will be noted that variations in the thickness of the upstanding rib will cause movements of the rib guide 38 toward and away from the feed wheel 34 as the shoe is being trimmed. However, the lever 94 being normally spaced from the roller 118 on the lever 116 by the adjusting screw 102, these movements will not be transmitted to the welt crease guide and it will at all times maintain its upward pressing action against the welt.

The cutter 20, seen best in Figs. 3 and 4, comprises a plurality of arms 130 in the ends of which are clamped cutting bits 132 of carboloy or similar material. These I bits cooperate with, although they do not touch, the upper periphery 134 of the dished feed wheel 34 to sever the surplus inseam material. As will be seen in Figs. 5 and 6, the face E of the cutter 20 lies in the same plane as the axis of rotation B of the feed wheel 34 and therefore passes above the lowest point of the periphery 134 (Fig. 3) of the feed wheel. In order that the bottom edges of the cutter bits 132, which are about one-fourth inch wide, clear the upper periphery 134 of the feed wheel 34 by a substantially uniform amount along their width they are positioned in the arms 130 in offset relationship, as seen in Fig. 6, i.e. with their bottom edges inclined slightly upwardly to the left. Were the face E positioned to the right of the lowest point of the feed wheel 34, the bits would be inclined in the opposite direction. Secured to a portion 136 o'f the machine frame closely adjacent to but not touching the cutter, is -a block 138. This block presents an effective barrier to chips adhering to the face of the rotating cutter which would otherwise be carried by the cutter back toward the work piece. Surrounding the cutter 20 and the barrier block 138 is a housing 140 (Fig. 1) and connected thereto is a conduit 142 through which chips are drawn by an exhaust fan or other yappropriate mechanism.

'Ihe mechanism for imparting welt beating motion to the feed wheel 34 will now be described. The shaft 74 (Fig. 1) which mounts the feed wheel extends downwardly passing between the arms 78 of thelever 76, through a pair `of bosses 144, 146 on the machine frame and nally terminating in a thrust bearing 148. A pair of brackets 150, \152 (Fig. 2) project downwardly from the thrust bearing 148 and receive between them on a wrist pin 154, the upper end of a driven crank 156. 'Ihe crank is driven by an eccentric 158 (Fig. 2) connected to the crank by a bearing 160. The eccentric is mounted on a shaft 162 which rotates in bearings 164, 166 and 168 in the lower part of the machine frame. The shaft receives its power from the main drive shaft 90 through a belt and pulleys 172 and 174. The main shaft 90 receives rotary power from a motor driven belt 176 and a pulley I178.

Surrounding the shaft 74 and mounted between the bosses "144 and 146 is a worm gear 180 which is driven by the above-mentioned worm 92. The worm gear is constrained from moving axially of the shaft 74 by its hub 182 which engages the boss 144 and a bearing 184 which spaces it from the boss 146. The hub 182 is connected by keys 186, 188 to the shaft 74 to impart rotary driving motion to the feed wheel 34 but the`keyways in the hub are of greater length than the keys permitting the shaft 74 to move axially relative to the hub as it is being driven.

Thus, as the welt of the shoe is gripped between the drivenffeed wheel 34 and the welt crease guide 36 to feed the shoe past the cutter 20, the above described eccentrically driven mechanism causes it to be continuously pounded at low amplitude and high frequency by the feed wheel 34 against the welt crease guide 36 as an anvil while the ridges `42 and the spurs 44 tend, not only to provide a positive gripping action to feed` the shoe, but also assist in counteracting strapping, which is the tendency of the welt to bend toward the upper, as shown in broken lines in Fig. 3a, by indenting the welt to relieve the troublesome stresses. Because the cutting bits 132 of the cutter 20 are designed to operate without touching the edge 134, a minimum gap of a few thousandths yof an inch being maintained and because of the high speed of rotation of the cutter, the movement of the edge 134 of the feed wheel 34 toward and away from the cutter bits does not impair the trimming action as might be the case if it were required that the bits maintain metal-to-metal contact with the edge 134.

While, by strict definition, a shearing action does not 'take place between the bits 132 and the edge 134 because there is no metal-to-metal contact, the gap between them is so small that the action on the stock or work is tantamount to shearing. In any event, however, the members 132 and 134 cooperate to produce the cut.

Because the feed wheel 34 is inclined on an axis forming an angle with the horizontal, rather than, for example, a cylinder rotating in a horizontal axis, the locus of a point on its periphery is not a straight line when viewed from above but rather a closed, generally elliptical curve as can plainly be seen in Figs. 5 and 6 which are plan views of the feed wheel. The projections 44 and the ribs 42 of the feed wheel 34 engage the welt 6 of the shoe lover a substantial area indicated in Fig. 7 as extending from C to D. A combination of these factors results in a force' applied to the `shoe in the direction as shown in the diagram of Fig. 5. This force may be resolved into two components, one being the force normal to the face E of the cutter and a second, parallel to the face E of the cutter. The normal force tends to feed the shoe and the parallel force tends to turn the shoe. The fulcrum of the turning force is the lowest point of the feed wheel 34 which, as seen in Fig. 5, is in alignment with the axis B. A second or left hand component, less severe, but also tending to turn the shoe in a clockwise direction occurs as the vfeed wheel grad- 1 ually relinquishes its grip von the welt. The reason the second turning component is less than the first is because the spurs 44 are no longer biting into the welt and forming elongated indentations 441, |but rather )are being withdrawn from those indentations. Nevertheless, the turning components are cumulative and in a clockwise'direction. While this turning of the shoe often assists in feeding the shoe around curves it just as frequently opposes it and an operators job is made all the more difficult thereby.

Also acting on the shoe is the cutting force imparted by the cutter as its bits chop into the inseam substance, or by the conventional cup-shaped rotary knife slicing across the inseam. (Note that the cutter rotates in a counterclockwise direction as viewed in Fig. 3.) To take advantage of this force to counteract tfhe turning tendency, the position of the fulcrum of this force was selected so as to result in -a turning moment counterclockwise as viewed in Figs. 5 and 6. The fulcrum is the outermost point of the welt crease guide, i.e. point F in Fig. 3, or the point against which the shoe is normally pivoted during trimming. Point F is in vertical alignment with the axis of rotation A of the welt crease guide. Therefore, the machine is constructed with the axis A -to the left of the axis B of the feed wheel or beyond the axis B when measured in the direction of feed which is from right to left. As seen Iin the drawings, the axes A and B lie in parallel spaced planes with the face E of the cutter lying in the same plane as does the axis B.

Similarly, the same results may beobtained by-advancing the cutter to the right of the point F Without changing the positions of the axes A and B, for example, as in conventional inseam trimmers wherethe axes A and B and the point F all lie in the same vertical plane. i While the `lever arm of the cutting force about its fulcrum F is less than the lever arm of either of the turning components, its magnitude is considerablyV greater resulting in a torque yielding substantial equilibrium. This permits the operator to control the rotative movements of the shoe more accurately than when the axes A and B occupy the same vertical plane as in conventional inseam trimmers. 1 v v Having thus described our invention, what We claim as new and `desire to secure by Letters Patent of the United States is: K

1. In an inseam trimming machine the combination with a feed member constructed and arranged to engage the outer portion of the inseam substance and a work supporting member constructed and arranged to engage the upper attaching surface of the welt, a rotary cutter comprising a plurality of chopping blades constructed and arranged to cooperate with an edge formed on the feed member to trim the inseam, means for rotating the cutter in a counterclockwise direction measured in the direction of feed, the work supporting member cooperating with the feed member to grip the welt between them, said supporting member being located at a point displaced from the point of cut measured in the direction of feed whereby said chopping blades impart a torque to said shoe about said displaced point as a fulcrum.

2. An inseam trimming machine having, in combination, trimming means comprising a rotatable cutter, the normal operation of said cutter imparting a force to said shoe, feeding means located adjacent said trimming means and including a rotatable welt crease guide constructed and arranged to enter the crease between the upper and the welt of a partially fabricated welt shoe, means for rotating the cutter in a counterclockwise direction measured in the direction of feed, the axis of rotation of said welt crease guide being spaced from the direction of said cutter force measured in the direction of feed of the shoe whereby the cutter force imparts a torque to said shoe about said crease guide in a counterclockwise direction measured downwardly.

3. An inseam trimming machine having, in combination, trimming means comprising a rotatable cutter, the normal operation of said cutter imparting a force to said shoe, feeding means located adjacent said trimming means and comprising a rotatable welt crease guide constructed and arranged to enter the crease between the upper and the welt of a partially fabricated welt shoe, a rotatable feed wheel engageable with the outlying margin of the welt on the side opposite the Welt crease guide, means for rotating the'cutter in a counterclock- Wise direction measured in the direction of feed, the axis of rotation of said rotatable feed wheel and the direction of'said cutter force projected to intersect said axis defining a plane, the axis of rotation of said crease guide being parallel to and spaced from said plane measured opposite to the direction of feed whereby the cutter force imparts a torque to said shoe about said crease guide in a counterclockwise direction measured downwardly.

4. An inseam trimming machine having, in combina-l tion, trimming means comprising a rotatable cutter, feeding means located adjacent said trimming means and comprising a rotatable welt crease guide constructed and arranged to enter the crease between the upper and welt of la partially fabricated welt shoe, and a feed wheel having a conical surface rotatable about a fixed axis and arranged to engage the upper eattaching surface of the welt, means for rotating the cutter in a cutting plane and in a counterciockwise direction measured in the direction of feed, the axis of rotation of the Welt crease guide being parallel with and spaced from said cutting plane.

5. An inseam trimming machine having, in combination, trimming means comprising a rotatable cutter, feeding means located adjacent said trimming means and comprising a rotatable welt crease guide constructed and arranged to enter the crease between the upper and welt of a partially fabricated welt shoe, and a feed wheel having a conical surface rotatable about a fixed axis and arranged to engage the upper attaching surface of the welt, means for rotating the cutter in a counterclockwise direction measured in the direction of feed, the axis of rotation of the welt crease guide being spaced from the axis of rotation of the rotatable feed wheel measured in the direction of feed of the shoe.

References Cited in the tile of this patent UNITED STATES PATENTS Germany Nov. 12, 1912 i... ma

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