US2273080A - Shoe stitcher structure - Google Patents

Description

INVENTOR EUGENE G. WOLF I A11To NEY' 3 sheets-sheet '1 E. G. WOLF SHOE STITCHER STRUCTURE Filed July 17, 1939 Feb. 17, 1942.

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Feb. 17, 1942. E. G. WOLF SHOE STITCHER STRUCTURE 3 Sheets-Sheet 2 Filed July 17. 1959 vINVENTOR EUGENE G. WOLF BYQQM AT ORNEY Feb. 17, 1942. E. WOLF SHOE STITCHER STRUCTURE Filed July 17, 1939 3 Sheets-Sheet 3 INVENTOR EUGENE G. WOLF Patented Feb. 17, 1942 SHOE STITCHER STRUCTURE Eugene G. Wolf, St.- Louis, Mo., assignor to Landis Machine Company, St. Louis, Mo., a corporation of Missouri Application July 17,1989, seria1No.284,819

10 Claims.

The invention relates to sewing machines and particularly the type of leather stitchers Aused in sewing shoe soles and uppers together, and

the invention consists in structure for eiectig and releasing thread and presser vfoot locks.

In most machines of this type it is customary to lock the thread against being pulled from the spool d uring a substantial portion of the cycle of operations of the machine and more specifically during the take up operation in which the surplus thread, fed to the Work and drawn through the same by the needle, is pulle'd back to tighten the stitch.

Also on such machines the presser foot is thrust against the Work to hold the work against movement through the machine during the greater part of the machine cycle but this thrust is released for a short period during each cycle to permit the work to be fed the length of the stitch for the succeeding operation.

Previously it has been customary to effect the thread lock by spring pressure and the spring would vary in its thrust, due to temperature conditions and other factors. The cramped space available for the spring makes it dicult or impossible to use a spring as long and as large as is desirable for satisfactory and permanent results.

Usually the presser foot is held in locked position by a ratchet and pawl device, the ratchet ffm lock released by the manual control indepeud teeth being intended to accommodate every variation in the thickness of the work. Obviously, the work .may be of a thickness intermediate successive ratchet teeth and obviously wear on i secure irrespective of the thickness of the thread or the thickness Vof the work, and which will remain secure irrespective of wear in the parts.

It is further desired to construct the lock parts so they will vrequire little space thereby facilitating assembly and replacement and also increasing the accessibility of adjacent mecha.- r

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Itis a. further object of the invention to provide a manual release for the new locking structure whereby bothV locks' may bereleased ,simultane'ously at any time in the' cycle of operations of the machine irrespective of the position 0f the machine earns which normally set and release the locks at stated periods in the cycle of operations.

These and other detailed objects of the invention as will appear from the following description are attained by the structure illustrated in the accompanying drawings in which- Figure 1 is a front elevation of th'e head of .a stitcher of the type described, `only the operating l0 parts essential to understanding the present invention being illustrated.

Figure 2 is a view taken from the left hand side of Figure 1 with some of the parts being 'broken away to more clearly illustrate the essenl tial mechanisms. ,The parts are shown with the 20 released by its cam on the main shaft of the.

machine.

Figure 4 is a view in theIl same direction, showing mainly the presser foot lock released by the manual control independently of its cam on the '35 main shaft.

Figure 5 is a view in the same direction, showing the thread lock released by its camon the main shaft.

Figure 6 is a similar view showing the thread ently of its cam on the main shaft.

Aside from the presser foot and thread lock devices, the machine corresponds to the Goodyear type of stitchers familiar to those skilled in the 35 art and includes a pedestal I, a.table or head 2 `having spaced brackets 3 journallingr the main cam shaft 4. The thread lock cam disk 5 includes the face cam groove 6 receiving the cam roller 1 on the end of cam lever 8. The presser 10 foot lock cam disk 9 includes the face cam groove I0 which receives roller II on cam lever I2.

B indicates the worksupport bracket on whichthe shoe sole S rests. The operating ends of the usual curved awl and needle are shown at I3 and 5 I4 respectively and oscillate about a commonaxis A- in the usual manner.

A presser foot arm I6 (Figure 3) oscillates about an axis I5 and its inner end I1 is pivotally connected to a forked jaw I8 on a rod I9 slidably mounted in a sleeve 20 having a pivotal mounting member 2| on a pin 22 on the machine frame. The lower end of sleeve 20 terminates in a jaw 23. 'I'he lower end of rod I9 has a steep square thread, and` a nut 24 on the threaded `por "5 tion/of the rod has a corrugated cylindrical exroller 28 is journaled on disk 216 at oneside off,

pivot 21. Throughout the major portion of the cycle of operations cam groove I9 holds lever I2 v in the position shown in Figure 2 and normally roller 28 tilts dog 25 to the position shown in Figure 2, holding nut 24 against rotation and therefore holding rod I9 against axial movement. Preferably roller 28 lifts upwardly on dog 25 moving sleeve and rod I9 and the presser foot arm I6 far enough to tightly clamp the work against its support bracket B.

A plate 29 is threaded on the upper end 0f sleeve 20 and an adjusting screw 30, threaded through plate 29, bears against the mounting member 2I and is held in adjusted position by a set screw 3I. A spring 32 yieldingly thrusts jaw I8, rod I9 and the inner end of presser foot arm I6 upwardly to maintain the presser foot in contact with the work.

During a short period* in the cycle of operating the work to be moved across bracket B by the usual feeding mechanism (not shown) subject only to the relatively slight friction by the presser foot exerted by spring 32.

Manually operated mechanism is provided for releasing the presser foot lock at any time in the cycle of operations of the machine. This mechanism comprises a rod connected at its lower end to a foot treadle (not shown) and at its upper end to a lever 36 pivoted to a shaft 31 journaled in the machine head and connected by a link 38 toa vertically movable bar 39. The front face of bar 39 contacts a guide pin 40 on presser foot arm I6 and the rear face of member 39 has an offset track 4I engaging the opposing face of an arm 42 pivoted at 43. A lug 44 on arm 42 engages the right hand end of a lever 45 pivoted on pin 22 and the left hand end of the lever engages pin 41 on disk 26 aligned with the journal of roller 28.

. When the treadle and rod 35 are depressed, slide 39 moves downwardly to the position shown in Figure 4 in which it thrusts arm 42 to the left, the thrustbeing transmitted through lever 45 to pin 41 which rotates disk 26l about its axis 21 and against the pull of spring 48 to move roller 28 to the position shown in Figure 4 in which dog 25 is freed from roller 28 to vrelease nut 24 and permit -it to be rotated by movement therethrough of rod I9 irrespective of the position of cam groove I0, lever I2 and disk pivot 21. Thereupon hook 49 on bar 39 engages pin 4 0 on the presser foot arm to tilt the same about its pivot I5 and lift thepresser foot from the work, rod I9 moving downwardly and its threads rotating nut 24 freely in dog 25.

The thread lock cam lever 8 is pivoted at 50 (Figures 2, 5 and 6), and a link 5I connected thereto extends through a sleeve 52. Nuts 53 on link 5I form means for adjusting the effective length of link 5I. Sleeve 52 has a lateral stem 52a (Figures 1 and 6) journaled in a collar 54 provided with an arm 54a. A crank shaft or bell crank lever 55 journaled on the machine head has an arm 55a pivoted to arm 54a. Another arm 55h has a notched outer end for receiving the corresponding end of a lever 56 pivoted on a shaft 51. The other end of lever 56 is shaped to oppose the surface of a grooved thread guide 58 to lock -the thread T against being drawn through the machine by the thread take up 59 (Figures 1 and 2) or' otherwise. When the low portion 6a of cam 6 engages roller 1, lever 8 is moved to the position shown in Figure 5, drawing link 5I, sleeve 52, collar 54 and arm 55a to the left and thrusting arm 5512 in an anti-clockwise direction and lever 56 in a clockwise direction to release thc thread. During the remainder of the cycle, cam 6, lever 8, link 5I, collar 54 and crank arms 55a and 55h and lever 56 positively hold the thread locking elements in locking position.

When the treadle is depressed to release the presser foot, as in withdrawing the work, it is necessary to release the thread lock also. Downward movement of rod 35 and the clockwise'rotation of shaft 31 rotates crank 60 on shaft 31 in a clockwise direction and moves a link 6I downwardly (Figure 6). The upper end of link 6I is connected to stem 52a (Figures 1 and 6) and may pull the latter downwardly from the position shown in Figures 2 and 5 to that shown in Figure 6.

As link 5I anchors sleeve 52 and the upper end of link 6I against movement to the right, the downward movement of link 6I, bringing arm 54a from the inclined position of Figure 5 to the horizontal position of Figure 6, causes crank shaft 55 to turn in an anti-clockwise direction and causes lever 56 to turn in the opposite direction and release the thread.

Spring returns the treadle rod and all the parts actuated thereby to normal position whenever pressure on the treadle is released.

The construction described provides a thread lock applied by levers and links rather than by spring pressure but, nevertheless, the pressure on the thread may be readily adjusted by shifting nuts 53.

The construction also provides a positive lock for the presser foot for any given thickness of work and does not depend upon the proper spacing of a series of ratchet teeth relative to the presser foot and work-supporting bracket as is required in the ratchet type locks previously used as illustrated, for example, in Patent 1,921,277, issued to the present applicant.

With the spring actuated thread locks and ratchet actuated presser foot locks as previously used, it has lbeen customary to adjust the locking elements every'couple weeks or so to maintain their effectiveness, Whereas machines with the present locking structure have been run without adjustment for a period of six months.

It will be understood that 'either the thread lock or the presser foot lock described herein may be used independently of each other but the preferred arrangementvcontemp'lates the use of both of these locks in association with each other, and their manual release by a common mechanisrn.

The principles of the invention may be embodied in structures differing in details from those illustrated and described herein and the exclusive use of such modifications as come within the scope of the claims is contemplated.

What is claimed is: 1. In a stitching machine, a thread lock including a thread engaging member, cam'mechpoint in the cycle actuated manuallyat any point in said cycle, a

linkage pivotally connected at its ends to said devices respectively, each of said devices upon being actuated swinging said linkage about its connection to the other device as an anchorage chine, the respective cams each having portions automatically releasing said lock and presser foot at desired points'during said cycle, and a part operatively connected to said member and presser foot for manually releasing said lock and presser footsimultaneously at any time during said cycle.

7. In a stitching machine, a thread lock including a thread engaging element, a cam driven lever, a pair of pivotally connected links connecting said lever and said element, a device for limiting the pivotal movement of said links whereby said vlever may move said element to clamp the thread, a part operable to shift said device to release said thread lock, a presser foot including a thrust-transmitting arm and a cam driven lever, a connection between said lever and said arm for holding them against relative movement to hold said presser foot in work clamping position, a member operable to release said arm from to positively move said Ielement towards and from the thread.

3. In a stitching machine, a thread lock, a device actuated mechanically during the normal operation of the machine, a device arranged to be actuated manually at the will vof the operator, members pivoted to each other and connecting said devices, each of said devices when actuated oscillating said members about a part of the other device as an anchorage, and an element having a connection to said members and movable positively thereby, when either of said devices is actuated, to control said thread lock.

4. In a stitching machin-e, a thread lock including a thread engaging element, a member oscillated during the cycle of operation of the machine, and a member arranged to be oscillated manually, each of said members having a fixed pivot, a linkage connected at its ends to said members respectively, a lever having one arm connected to said element and having its other arm connected to said linkage, each of said members, when oscillated, moving said linkage about its connection to the other member to actuate said lever to positively move said element to engage and disengage the thread.

5. In a stitching machine, a thread lock including a thread engaging element, a cam actuated lever, a bell crank with its arms pivotally connected to'said element and said lever respectively whereby cammed movement of said lever swings said bell crank about its pivot to oscillate said elem-ent to release and engage the thread, a manually actuated part, and a connection between the same and said bell crank whereby movement of said part swings said bell crank about its pivot to positively oscillate said element to release and engage the thread.

6. In astitching machine, a thread lock including a thread engaging member anda cam driven lever for actuating the same to positively clamp the thread during a portion of the` cycle of operation of the machine, a presser foot including. thrust-transmitting arm and a cam driven lever for actuating the same to positively hold the presser foot against the work during a' portion of the cycle of operation of the masaid connection, and means actuated by a single manual operation for actuating said part and member simultaneously at any point in the c fcle of operation of the machine.

8. In a stitching machine, a thread lock including a thread engaging element and a lever for actuating the same and having a fixed pivot,

an operating shaft, a cam thereon, means movable positively in opposite directions by said cam and having a link connection to said lever, a manually operated means having a link connection to said lever, each of said means and its link connection forming an anchorage for the other link connection and each of said means being operable independently of the operation ofthe other of said means to move said lever and the element actuated thereby to and'from the thread.

9. In a stitching machine, a thread lock including a thread engaging element, a cam operated member, a manually operated device, a lever having a pivotal connection at one end to said element, a linkage pivotally connected at its ends to said lever and to said member respectively, Aa linkage pivotally connected at its ends to said 4lever and said device respectively, said second-mentioned linkage swinging on its pivotal connections to said lever and devi-ce to accommodate movement of said lever by said member and said first-mentioned linkage, Vand said iirst-mentioned linkage swinging on its pivotal connections to said lever and member to accommodate movement of said lever by -said device .and said second-mentioned linkage.

10. In a stitching machine, a thread lock in-

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