US2140532A

US2140532A - Trimming machine

Info

Publication number: US2140532A
Application number: US148079A
Authority: US
Inventors: Axel A Lawson
Original assignee: United Shoe Machinery Corp
Current assignee: United Shoe Machinery Corp
Priority date: 1937-06-14
Filing date: 1937-06-14
Publication date: 1938-12-20
Anticipated expiration: 1955-12-20
Also published as: DE687832C

Description

Dec. 20,1938. v v A. A; LAWSON 2,140,532

TRIMMING MACHINE Filed June 14, .1937 a Sheeis-Sheet ,1 7.

M I //v\/-NTU Dgc. 20, 1938.

A.YA. LAWSON TRIMMING MACHINE Fi led June v14, 1957 3 Sheets-Sheet 2 AVE/v7.0a; My,

'40 time of a bed-lasting operator.

Patented Dec. 20,

I v I I r Tm f eAxeI A.-1M,W m to United Shoe Machinery I son, N, 1., a corporation oi New Jersey Corporation, Pater- Application June, 1921. Serial No. 148,019

13 Claims. (of. 1z-ss.s

, This invention relates to shoe-trimming machines and is illustrated as embodying improvements, designed to facilitate the operation known as toe-lining trimming. This operation is now common in the manufacture of shoes of the type in which the toelasting is done with cement instead of tacks, and

7 in which the outsoles are to be attached with' cement. To obtain satisfactory toe-lasting and a strong bond of adhesion between the toe of an insole and thejoverlasted margin of the outer layer of the upper, the operation above mentioned consists in severing a strip from the corresponding margin of the inner layer, and one or u more intermediate layers of materials that would, if not so trimmed, lie between the insole and the overlasted margin of the outer'layer.

This-trimmingoperation is now being performed in many shoe-factories by bed-lasting operators.

o ment-applying operation for preparing the shoes for toe-lasting may both be performed before the shoes aredelivered to the bed-lasting operators.

A trimming machine of the type herein disclosed may be used to perform the trimming step 35 of the aforesaid improved method, since it provides for severing the aforesaid strip of all the layers except the outer'layer more rapidly and more evenly than it can be done by hand, and without requiring a bed-lasting machine, or the Moreover, one trimming machine is sufiicient to keep pace with .a battery of four or five bed-lasting machines. When the partially fabricated shoes reach that stage that calls for the trimming operation above 45 mentioned, they are commonly side-lasted with staples,.or otherwise, up to points slightly behind the tip-line, but the toes are merely pulled over. The trimming operator must first pullout the temporary toe-tack of each shoe to release the unlasted upper materials at the toe. Although these materials then loosely envelop the toe of the last, the lasted condition near the tip-line presents serious difficulties in beginning and ending 55 a trimming operation without cutting or othercut will be even and uniformly close to the inwise' damaging the margin of the outer layer, which should be left intact for toe-lasting.

" To deal with these conditions the present invention provides. a trimming machine in which a finger is arranged to project into the space between the inner and outer layers or margins of unlasted upper materials loosely enveloping the toe of the insole of a partially fabricated shoe, and in'which a reciprocatory cutting blade that confronts the bottom of the insole is reciprocated 1 to cut through the inner layer or margin toward the outer margin while the finger braces the inner margin close to the line of cutting. Preferably the finger. is provided with a sharp edge with which the reciprocatory blade cooperates to sever 1 the strip with successive shearing cuts. In any. event, the outer margin runs behind the finger and the latter has suflicient thickness adjacent to the line of cutting to maintain that margin beyond the range of the reciprocatory blade.

The invention also provides power-driven means arranged to tension the inner layer by drawing its margin away from the plane of the insole at a point just ahead of the cutting locality,.to the end that the course of the trimming sole, however much or little the materials to be trimmed may have been wrinkled by being pulled over before being trimmed. As'herein illustrated, the tensioning means comprises a pair of driven rolls arranged to grip the margin to be severed and to feed the work thereby, the diameters of the rolls being small and one of the rolls being arranged to project between the inner and outer margins of the upper materials.- This one of the rolls is preferably provided with a pointed end which, being ahead of the aforesaid finger and projecting beyond the end of the latter, is the first to enter between the inner and outer margins. The pointed end facilitates the beginning 40 of a trimming operation by wedging apart the inner and outer margins far enough to enable the finger to enter between them. The pointed roll thereafter deflects the outer margin so that it must pass behind the finger while the inner margin passes in front of the finger and into the path of the cutting blade. The tensioning effect of the rolls is obtained by arranging their axes in oblique relation instead of normal relation to the path of travel of the materials passing between them.

Referring to the drawings,

Fig. '1 is a front elevation, partly in section, of a trimming machine embodying'the present invention; u

Fig. 2 is an elevation partly in section, as viewed from the right-hand side, and includes a crosssection of a partially fabricated shoe in process of being trimmed; r

Fig. 3 is an elevation of one of the feed-rolls and asectional view of its bearing structure, the vertical arrangement of the roll, as drawn, instead of its actual inclined arrangement in the machine, being merely for the sake of convenience of execution;

Fig: 4 is a perspective view of the parts that constitute the cutting mechanism;

'Fig. 5 is a top-plan view of the forepart of a partially fabricated shoe in process of being trimmed, and includes portions of the cutting members, a trimming guide and the feed-rolls in section;

Fig. 6 is a side elevation, partly in section, of the movable cutter;

Fig. 7 is a side elevation of the holder that carries the movable cutter; and

' Fig. 8 is a front'elevation of a stationary finger that cooperates with the movable cutter.

The type of shoe that requires the trimming operation under consideration comprises an insole ill made without lip, feather, or rib and -having a smooth uninterrupted bottom surface against which the overlastecl margins of upper materials may be secured with metallic fasteners, cement or both. The upper materials com prise an outer layer Ii, usually of leather, an

inner layer or lining 12 of woven fabric or other'in the strip of waste in process of being severed, the separation is merely to give the layers individual identity for purposes of description. In practice, the toe-box l3 commonly comprisw woven or felted fabric impregnated with a sub-- stance capable of being rendered tacky by a solvent, and the tacky condition is usually brought about prior to the pulling-over operation. Consequently, it is to be understood thatthe layers [2, I 3, and I 4 will,'or may, be united by bonds of adhesion due to the tacky impregnant in the toe-box I3 and that these elements constitute,

in efiect, a three-ply lining from which a marginal strip is to be severed close to the insole without-severing the corresponding margin 15 of the outer layer. l

According to common practice, after the abovedescribed elements have .been pulled over on a last IS, the shoe is side-lasted with staples-l1 (Fig. 5) which extend through the overlasted margins of the outer layer It and the inner layer l2 and are anchored in the insole. 'At this stageof fabrication, the'toe of the shoe is left in a pulled-over condition with a single tack. not shown, securing the pulled-over margins of the several layers to the insole near the middle of the toe, the nearest side-lasting staples or temporary tacks 88 being a short distance behind the tip-line. The shoe is ready for the trimming operation hereinafter described, except that it is necessary to pull out the toe-tack to release all the layers at the toe-end. The margins of these layers then loosely envelop the toe of the insole and aremore or less distorted in consequence of having been pulled over and secured by the toe-tack while the toe-box I3 is under.

the influence of a solvent. 7

The operation to be described consists in severing a strip from the margin of the lining (layers i2, i3, and 18) close to the insole, to the end that when the margin Q5 of the outer layer is subsequently lasted, it will lie in contact with the bottom of the insole to which it willbe secured with cement.

The mechanism for severing this strip as pictured in Fig. 5 is shown in its entirety in Figs. 2 and 4. The actual cutting is done by a blade i8 provided with an acute cutting edge is that extends in oblique relation to its lines of movement and in oblique relation to the direction in which the work is fed at the cutting locality. This cutting blade is carried by a reciprocatory bar or plunger 29 and is arranged in underslung relation thereto, the bar being far enough above the blade to overhang and clear the margins of the upper materials. The blade is directly attached .to a holder 2! by a clamping screw 22, the shank of the blade being provided with a vertical rib 23 (Fig. 6) and theholder 2! being provided with a corresponding groove in which the rib is fitted to provide for vertical adjustment of the blade and to prevent its turning about the axis of the screw. A slot 24 is formed in the holder 2| to enable the blade and the screw to be adjusted up and down. The thread,

of the screw engages an internal thread 25 in the shank of the blade. The holder 2i is pro-' vided with a shank 26,'and this shank is mortised into a groove in'the bar 20 and is secured to with a device to prevent its turning, everso little,

about its axis. For this purpose, a fiat bearing block 3.4 is secured to'the under side of the bar by a bolt35 and is seated on a stationary bearing piece 36 afiixed to the frame 23 by screws 31.

v The strip to be severed is braced against the cutting thrust of the blade I8 by a finger 38 arranged to project downwardly into the space between the outer margin I5 and the inner margin of upper materials. This finger is afiixed to the front face of the forward bearing 28 by screws 39. Its lower extremity is blunt and of the same width as the blade l8 and is arranged in register therewith, the cutting bed or work-engaging face 40 of the finger having a sharp'edge 87 arranged to lie parallel with the path in which the work is fed and to extend across and touch the cutting edge l9 to have a shearing eifeot as the blade it! moves in the cutting direction. The adjustable connec tion between the blade l8 and the holder 2i provides for establishing a shearing relation.

As the blade l8 grows shorter in consequence of being sharpened, it may be advanced toward the finger 38 by sliding the shank 26 of the bladeholder along its hearing in the bar 20 when the cap-screw 21 is loosened.- As'shown in Fig. 2, the

mortise connection between the shank and the bar is inclinedmnd the slot 4| formed inthe shank to bar relieves the cap-screw-2'I of virtually all stress except that required to clamp the shank against the bar. To counteract up and down components of adjusting; movement of the blade-holder 2| the to insure'a true shearing relation with the stationary finger 36.. In practice the blade should be so adjusted that its point (see Fig. 4) will underlie the finger 36 when the bar 26 is at its forward limit of reciprocation, to the end that the cooperative edges of the blade and the finger will remain in contact with each other and maintain a V-shaped throat for the reception of the materials to be severed.

The machine is also provided with an underslung trimming guide, the work-engaging portion of which is a thin, flat plate 42 arranged to underlie the blade l6 and bearon the margin of the insole as shown in Figs. 2 and 5. The shank of this trimmin guide is mortised into a holder 45 and is secured thereto by a screw 44. The holder 46 is aifixed to the front faceof the .frame 29 by screws I45. The guide 42 maintains the insole at a level slightly below the blade l6, to the end that the trimmed materials will project slightly abovethe insole to be folded over on the latter when the toe of the shoe is subsequently lasted, and at the same time to enable the untrimmed margin l of the outer layer to lie in contact with the insole and thereby derive the full benefit of the bond of adhesion by which it is to be secured to the insole.

The margin comprising the layers to be severed may be gripped, fed, and tensioned with a component of updraft by a pair of feed-

rolls

45, 46 arranged ahead ofthefinger 96 and the blade l6 only far enough to clear them. The work-engagine'p rtions of the feed rolls are preferably fluted to render their feeding effect virtually-positive. Because the feed-rolls are necessarily of small diameter'to' enable them to operate in'narrow spaces, their axes are arranged in converging rela- Ition to provide clearance for mountings and driving means as pictured in Fig. 2 (see also the

broken lines

45 and 46 in Fig. 4 which represent 45 verging relation, the work-engaging portions of their axes). Moreover, to counteract this conthe rolls are tapered with the result thatthe portions that actually p the layers of the work will lie virtually in parallel relation to each other as shown in Fig. 2. The axis of the roll 45 is fixed but that of the roll 46 is movable'to provide for l separation of the rolls when it is desired to intro duce the work between them. Again, 'theworkengaging portion of the roll 45 is tangent to the plane of the cutting bed 46 (Fig. 8) of the-finger '36. The details of the bearing structure in which the roll 45 is mounted are shown in Fig. 3. This structure comprises ball-bearings 41 enclosed in a sleeve 46. An ear 49 formed on the sleeve is amxed to the frame 29 by screws 56. The spindle 5| ofthe feed-roll -45 extends upwardly through the ball-bearings and is provided with a pulley 52 by which the roll may be driven.

' ,The bearing structure for the feed-roll 46 is similarto thatshown in Fig. 3 except that instead of being provided with an ear 49 it is provided with two confronting ears 55 arranged to straddle a boss 54 proglecting from the sleeve of the feed-' roll 45. v The ears 5! and the boss 54 are connected by a hinge-pin 55 about which the feed-roll 46 and its bearing structure may swing sufliciently to provide for introducing the work between the feed-rolls. A link 56 for imparting movement of approach to the feed-roll, is connected to the corresponding bearing sleeve by a pivot-stud 51 Continuous rotation is. imparted to the 'feed-,

rolls by a belt 6i that runsover a driving pulley 62' (Fig. 2), an idler 65, a pulley 64 afiixed to the feed-roll 46, an idler 65 and the pulley 52 of the feed-roll 45, and thence backto the driving pulley '62. The idler 65 is mounted on'one arm of a bell-crank lever 66, the fulcrum-stud 61 of which is screwed into' the frame 29. The other arm 'of'this lever is stressed by a tension'spring 66 in a directionsuch as to tension the belt 6i and therebyretract the feed-roll 46 normally from the feed-roll 45 but to yield'in response to depression of the. treadle bywhichithe feed-roll- 46' is shifted toward the feed-roll 45 to grip the interposed work. One end of the spring 66 is attached to an anchoring pin 69 ailixed to the frame 29. The driving pulley 62 is afilxed to a countershaft 16,.journaled in a bearing member H and provided with a larger pulley 12 to which rotation is transmitted by'a belt '13. This belt is driven by a pulley 14 carried by'the shaft 15 of an electric motor '16. The bearing member H is provided with slots '11 through which clamping bolts I6 (Fig. 1) extend to secure the member to the frame 29, the slots 11 affording a range of adjustment for tightening the belt 13., The small diameter of the pulley 14, the large diameter of ,the pulley I2. and the small diameter of thepulley 62 afford a great. reduction in the v speed of rotation of the feed-rolls with respect to thatof the motor shaft 15. l

The shaft 15 is also provided with a driving pulley 66 from which rotation is transmitted by a belt 6| to a driven pulley 62 ailixed to the shaft 3| that carries the eccentric of the cutting 'mech-' anism. This transmission operates the cutter i6 at high speed.

As shown in Fig. 2, the tapering formation of the feed-roll 45 and the small diameters of its work-engaging portion enable it to project readily into the space between the outer margin l5 and the corresponding inner margin of theupper the blade is correctly adjusted.

Referring to Fig. 1, the feed-rolls are drivento feed the work from right to left. Since the insole of a shoe must pass under the trimming guide 42, the work-engaging surface of which'is virtually horizontal and parallel to the plane of the trimming cut, the feeding movement of the shoe will be virtually horizontal so long as the bottom of the insole is held in contact with this' trimming guide. The axes of the feed-rolls lie in a plane indicated by a broken line I00, which,- instead of being exactly normal to the direction of feeding movement, is oblique with respect thereto. Moreover, the pitch of this plane is course-of trimming and a virtually uniform pro-' jection of the trimmed margin above the level of the bottom of the insole.

' Assuming that the operator is about to presen ashoe to be trimmed by the described machine,

the feed-roll 46 will stand initially away from the feed-roll 45 by reason of the tension of the belt 6i due to the applied force of the spring fit. The shoe will be presented not as shown in .Fig. 5 but will be held first with itsheel end-at the left of the cutting blade l8 and with the starting point 83 in register with the lower end 86 of the feed-roll 35, which, as shown in Figs. 1 and 3, is pointed to facilitate its entrance between the outer margin l5 and the corresponding inner margin. At this stage the operator will tip the shoe to the rear to insert the point of the roll between the inner and outer margins-and, having done so, he will depress the treadle to shift the feed-roll 46 toward the roll 45. The feedrolls now grip the inner margin and bend it to an erect position while feeding it into theV- shap d throat formedby the cutting edge is and the lower edge of the surface of the stationary Once the feeding operation takes effect, the roll 45 enters farther the space between the inner and outer margins, thus spreading them apart far enough to admit the finger 38, whereupon the trimming cut runs into the inner margin. The operator thereupon tips the shoe forward to level the toe portion of the insole. The margin of the insole is thus brought face to face with the trimming guide 42 and the trimming cut progresses around the toe end of the insole, the margin of which is maintained in contact with the trimming guide not only by the operator but also by the updraft of the feed-rolls on the margin gripped thereby. As the trimming progresses around the toe, the operator swings the heel end of the shoe toward him and thence to the right, the margin in process of being trimmed being guided meanwhile-by the feed-rolls, the front face 40 of the finger 38 and the rounded corner 85 (Fig. 5) of the trimming guide 42. At the same time the outer margin I5 is deflected by the feed-r011 45 so that it must pass behind the finger 3B. As the trimming cut. approaches the terminal point 86 (Fig. 5), the operator will again tip the shoe toward the ear to enable the cut to run out at this point where both margins are overdrawn upon the insole and secured thereto.

In addition to bending the inner margin to an erect position, the feed-rolls smooth out wrinkles therein, including the two major wrinkles (dogears) usually formed at the toe incidentally to such as to develop a slight component of updraft .of the marginthat is gripped and being fed by into the space between the outer margin and the inner margin of unlasted upper materials loosely enveloping the. toe of the insole of a partially fabricated shoe on a last, and power-driven cutting means including a reciprocatory cutting blade arranged to cut through said inner margin toward the outer. margin, said finger being arranged to brace the inner margin close to the line of cutting and having suficient thickness adjacent to said line to maintain the outer margin beyond the range of said blade.

.2. A trimming machine as defined in claim 1, comprising also a'slender, pointed member arranged ahead of said finger to effect initial separation of said inner and outer margins and thereby facilitate the insertion of said finger between the margins.

3. A trimming machine as defined in claim 1 in which said finger is provided with a sharp shearing edge arranged to cooperate with the cutting edge of said blade to sever the inner margin.

4. A trimming machine as defined in claim 1, comprising'also power-driven means arranged to tension the inner margin with draft away from the plane of the insole ahead'of, but close to, the cutting locality.

5. A shoe-trimming machine comprising power-driven cutting means and a stationary cut ting bed arranged to sever an inner margin with out severing an outer margin of unlasted upper materials loosely enveloping the toe of the insole of a partially fabricated shoe on a last, a pairof rolls arranged to grip said inner margin ahead of but close to the cutting locality, one of said rolls being formed and arranged to project between said margins, and power-driven means by which said rolls are rotated to feed the'uncut stock of said inner margin to said cutting means.

6. A trimming machine as defined in claim 5, in which the axes of said rolls are oblique and so pitched with respect to the path of the work at the cutting locality as to tension said inner margin away from the plane of the insole.

'7. A trimming machine as defined in claim 5 in which the axes of said rolls converge toward the work-engaging portions of the rolls and in which said work-engaging portions are tapered to counteract the converging relation of the axes.

8. A trimming machine as defined in claim 5 comprising manually operable means by which the work-engaging portions of said rolls may be given relative movement of approach to grip the inner margin. p

9. A trimming machine as defined in claim 5 in which the work-engaging portions of said rolls are arranged to maintain the inner margin in a plane virtually normal to the cutting plane of said cutting means.

10. A trimming machine as defined in claim 5 in which said cutting means comprises a reciprocatory blade and a stationary finger, the blade being arranged to cut through the inner margin toward the outer margin, and saidfinger being arrangedv to project between the margins to brace the inner margin against the thrust of said blade. 11. A trimming machine as defined in claim 5 comprising also a trimming guide the work-engaging portion of which is a smooth plate formed and arranged to bear on the bottom of the insole abreast of the cutting locality and to engage the inner surface of the upper material lying against the perimeter of the insole.

12. A shoe-trimming machine comprising a virtually horizontal bar and power-driven mechanism for reciprocating'it lengthwise, an underthe outer margin beyond the range of said blade.

therefrom far enough to enable the bar to overhang and clear the unla'sted margins of layers of upper materials loosely enveloping and projecting above 'the'insole 'of a partially fabricated shoe presented'bottom-up for trimming, and. a stationary finger arranged to project downwardly between the margin of 'the outer layer and that of an inner layer to brace the latter margin against the cutting thrust of said blade and to maintain 13.1 shoe-trimming machine comprising a stationary finger one surface of which constitutes a cutting bed and is provided with a sharp shearing edge, power-driven cutting means including a reciprocatory blade having a cutting edge in oblique relationto said shearing edge to form a V-shaped throat, and a pair of power-driven rolls arranged to grip the material to be trimmed and iced it into said throat, one of said rollsbeing behind but tangent to the plane of said cutting bedsurface and so mounted as to be capable of pro 'jecting between the margin of an outer layer and the margin of an inner layer of unlasted up- 'per materials loosely enveloping the toe of the insole of a partially fabricated shoe on a last. 7 'AXEL A. LAWSON.