US2032311A - Sewing machine - Google Patents

Description

Feb. 25, 1936 F.R!CKS ETAL 2,032,311

SEWING MACHINE Filed Feb. 6, 1954 4 Sheets-Sheet 1 m5 #6. mm a, W

$7 fWW Feb. 25, 1936, cKs ET AL 2,032,311

SEWING MACHINE Filed Feb. 6, 1934 4 Sheets-Sheet 2 *r 5 DJ I Feb. 25, 1936. F. RICKS ET AL. 2 3

SEWING MACHINE Filed Feb. 6, 1934 4 Sheets-Sheet 3 F. RECKS ET AL SEWING MACHINE Filed Feb. 6} 1934.

4 Sheets-Sheet 4 Patented Feb. 25, 1936 SEWING MACHINE Fred Ricks, Harold Ernest Elliott, and Frank Coleman Choice, Leicester, England, assignors to United Shoe Machinery Corporation, Paterson, N. .1., a corporation of New Jersey -Application February 6, 1934, Serial No. 709,916 in Great Britain November 4, 1933 10 Claims.

The present invention relates to sewing machines and particularly, but by no means exclusively, to hooked needle sewing machines such as are used, for instance, in the manufacture of shoes.

The invention willbe explained by way of illustration and not of limitation in connection with curved hooked needle chain stitch sewing machines of which the machine illustrated and described in the patents to Eppler No. 1,108,560 dated August 25, 1914 and Topham No. 1,099,328 dated June 9, 1914 is an example.

In machines of the type disclosed in the patents above referred to, the tension exerted on the thread by the agency of the usual tension device plays an important part in determining the propenformation of the seam, and requires to be adjusted with some nicety to deal with changing work conditions. The usual tension device is a friction device, and the actual tension being exerted in any given circumstances of adjustment is not, therefore, reliably constant or readily ascertainable by the operator of the machine, and the disturbance to meet other conditions of a condition of adjustment found by trial and error appropriate to one class of work makes it a matter of no small difficulty for the operator to restore the same tension conditions when he so desires.

In applicants pending application Serial No. 695,140, filed October 25, 1933, an invention is disclosed, the objects of which are to provide increased facilities'for effecting such restoration of conditions previously determined as appropriate to a given case and to provide tension devices for such machines which shall reliably create, as desired, tension of a determinate amount."

The present invention has for its object to improve and simplify mechanisms of the same general character as those disclosed in applicants prior application, and with this object in view, the several features of the present invention consist in the novel and improved devices and combinations of devices hereinafter described and claimed, the advantages of which will be appar- Figure 6 is a. detail sectional view, taken'on the line 5-5 of Figure 3; Figure '1 is a detail ver-. tical sectional view of a portion of the mechanism illustrated in Figure 3; Figure 8 is a detail view in rear elevation of certain of the parts illustrated in Figure 3; and Figure 9 is a. detail view in side elevation of certain of the parts illustrated in Figure 1.

The illustrated machine comprises a tension wheel 34 having a pair of discs the margins of which are notched and the projections formed by which notches are bent to furnish a V-shaped groove to receive the thread. The discs are secured to the right-hand end of a horizontal spindie 35 extending from right to left of the machine, which spindle is rotatably mounted in a. bracket 36 secured to the rear of the machine frame. The tension wheel spindle 35 has keyed on it an internally and externally coned clutch member 31 (Figs. 3- and 'l) which can slide on the spindle 35. An internally coned clutch ring 38 is supported by pins 39, which are secured in a yoke to, and is withdrawn by Pins 44 mounted in the arms of a yoke 45 secured to a horizontal shaft 46 rotatably'mounted in the block 42. The pins 44 engage a member 41 of a ball bearing 48 positioned between the clutch member 31 and-a collar 46 secured on a sleeve portion 50 projecting from the clutch member 31. The clutch ring 36 is prevented from rotating about the axis of the pins 35 by links 5| secured at one end to the ring 36 and having at their other ends recesses which engage the pins 44. The shaft 4| has secured on it an arm 52 which is connected by a link 53 to a cam lever 54 of the machine which controls the thread. The shaft 46 has secured to it an arm 55 connected by a link 56 to a lever |56 associated with stop mechanism of the machine for a purpose hereinafter described, the lever I55 being moved in a clockwise direction as viewed in Figure 4 asthe machine comes to rest.

The externally coned flange 51 hereinbefore referred to is secured to a three-armed flange 58 I formed on one end of a second shaft 53rotatably mounted in the bracket 36 in axial alignment with the shaft 35. The externally coned flange 51 is supported by a head I56 (Figure 7) formed on one end of the shaft 35, relative endwise movement between theflange 51 and head I59 being prevented by a plate 68 secured to the head. A ball bearing 6| is interposed between the end of the shaft 59 and the head I59.

The shaft 59 has projecting from it a pin 62 to which is connected one end of a wire 63. The wire 63 is wound round the shaft 59 and its other end is secured to one end of a helical tension spring 64. The other end of the spring 64 is connected to an arm 65 secured on a shaft 66 rotatably mounted in the bracket 38. Also secured on the shaft 88 is an arm 61 which is connected by a pin and slot connection 68 to a rod 69. The rod 69 extends from the back to the front of the machine and may be adjusted lengthwise to adjust the tension of the spring 64. For adjusting the rod 69, it is provided with a screw threaded portion which is threaded through a stud. 2| mounted on the frame of the machine. At its forward end, the rod 69 is provided with a hand wheel 10 conveniently accessible to the operator by means of which the rod 69 may be rotated to secure the desired adjustment in the tension of the spring 64. To indicate the condition of the adjustment to the operator, an arcuate scale 22 is formed on a fixed plate 23 and a pointer 24 is also provided which is pivoted on the stud 2| and is arranged to be moved over the scale'when the rod 69 is adjusted. The pointer 24 has extending from itshub a short arm 25 having formed in it a recess 26 which is engaged by a pin 21 extending upwardly-from a block 28mounted to move with the rod 69. The block 28 is substantially U-shaped when viewed from above, and its arms are arranged one at the front and one at the rear of the stud 2| and by their alternative engagement with the stud 2| limit the amount of adjustment which can be iven to the rod 69. The block 28 is mounted to slide between flanges 29 projecting from the machine frame and is held from rotation by these flanges. As has been indicated, the hand wheel 70 is within easy reach of the operator as he stands in his normal operative position in front of the machine, and the pointer 24 and scale 22 are readily visible to him in this position.

Movement of the shaft 59 under the influence of the spring 64 is limited by the engagement of a lug 13 (Fig. 8) on a collar 14 secured on the shaft 59 with a plunger 15 which is backed by a spring 16 (Fig. 5) the plunger and spring being carried by the bracket 36 and the spring 16 being stronger than the spring 64. The spring 16 and plunger .15 provide a buffer or yielding stop which yieldingly resists the rapid movement of the lug 13 under the influence of the spring 64.

When; during the operation of the machine, the take-up lever is setting the previously formed stitch and is pulling thread from the supply, the internally andexternally coned clutch member 31 is in engagement with the externally coned flange 51 and the clutch ring 38 is disengaged from the member 31. The tension wheel is, therefore, connected through the shafts 35, '59 to one end of the spring 64 which as the take-up is moving in a direction to set the previous stitch and draw thread from the supply is further tensioned (it being understood that the thread lapped round the wheel cannot slip around the same) and through the tension wheel exerts tension on the thread, the final amount of tension being primarily dependent upon the previous adjustment of the hand-wheel l0 and to a lesser degree on the extent of rotation of the tension wheel. After the take-up has finished its movement to set the previous stitch and draw thread from the supply the clutch ring 38 is moved by its cam lever 54 into engagement with the member 31 and moves this latter member axially away from the externally coned flange 51 (so that in effect the tension wheel is locked) and the shaft 59 is free to be returned by the spring 84 until the lug 13 on the collar 14 engages the plunger I5.

At the time in the machine cycle when the needle is moving back and pulling a loop of thread through the work and exerting a pull on the preceding loop, the tension wheel is prevented from rotation by the engagement of the clutch ring 38 with the clutch member 31. To allow the needle to obtain thread during its backward movement, the usual stop against which the auxiliary take-up is moved by the pull of the needle on the thread before the needle reaches its fully back position is, in the construction being described, arranged to yield at this time so that the needle may obtain by such yield thread during its final backward movement by movement of the auxiliary take-up, but means is provided to make the action of the stop positive and effective during movement of the main take -up to set the previous stitch and draw thread from the supply. In this way drawing of the thread from the supply is effected solely by the main take-up and the needle does not have to pull any thread from the supply and is not subject to the .heavy pull of the spring 64. 7

Referring to Figure 9, the main take-up lever 88 is pivoted at 8| to the machine frame and is operated by a cam on the cam shaft of the machine. The auxiliary take-up lever 82 is pivoted at 83 on the machine frame and is controlled by a comparatively light spring 84 connected at one end to the auxiliary take-up ,lever and at the other end to a block 85 which is adjustable by means of a threaded rod 86 and nut 81 in a guideway in the machine frame to adjust the tension of the spring.

A pointer 88 formed on the block 85 and a scale 89 on the frame provide means whereby the tension of the spring 84 is indicated to the operator and whereby the tension of the spring may be adjusted a definite and known amount. Movement of the auxiliary take-uplever 82 under the influence of the spring 84 is limited by a stop (not shown). The auxiliary take-up lever 82 has adjustably fixed on it an angled block 98 which, during the upward movement of the main takeup lever88 is engaged by a pin 9| secured in the main take-up lever, for a purpose hereinafter described. An arm 92 is pivoted on the same pivot as the auxiliary take-up lever 82 and is normally held upwardly against a stop (not shown) by a spring 93 connected at one end to the arm 92 and at the other end to a block 94 which is adjustable by means of a threaded rod 95 and nut 96 in a guideway in the machine frame to vary the tension of the spring 93.

A pointer 98 on the block 94 and a scale 99 on the frame serve to indicate to the operator the tension of the spring 93 and permit the tension to be quickly adjusted a known amount. The arm 92 is arranged to be engaged by an arm 91 on the auxiliary take-up lever 82 during the operation of the machine, as will hereinafter appear.

During the operation of the machine when the main take-up lever 88 is rising to draw thread from the supply, the pin 9| in the take-up lever 88 engages the block 98 near the end of its upward movement and swings the auxiliary take-up lever 82 in a direction to cause that lever to draw from the supply a small amount of thread in addition to that drawn by the main take-up. The main take-up draws from the supply an amount of thread slightly less than is required for the next stitch, and the main take-up lever 80 and pin 9| cause the auxiliary take-up to draw the rest of the thread required. When the main take-up lever is descending and the usual looper is placing the thread round the needle, the auxiliary take-up is under the control of the comparatively light spring 84. At the time in the machine cycle when the needle has pulled a loop of thread through the workand has nearly reached its rearmost position, the arm 91 comes 'into engagement with the arm 92 and, during the last part of the rearward movement of the needle,

when the needle is pulling the previous stitch tight, movement of the auxiliary take-up is resisted by both springs 94, 93.

' is drawing thread from the supply and setting the previous stitch against the tension of the spring 64 and the stop pin 9I is removed from the block .90 while the looper is wrapping the thread round the needle and while the needle is drawing a loop of thread through the work and pulling the last stitch tight. The three springs 64, 84 and 93 are independently adjustable and the adjusting means for each spring is provided with indicating means so that the operator can tell at a glance the tension in the various springs at any time and can readily adjust the tension of the springs by a known amount to suit the character of the work to be operated upon.

As in the case of the machine disclosed in the patents hereinbefore referred to, the machine is automatically stopped when sewing is discontinued with the needle retracted and accordingly it becomes necessary to provide means for releasing the tension wheel 34 on the stopping of the machine so that thread may be drawn from the supply when the shoe is, drawn away from. the machine. The releasing of the tension wheel when the machine stops is effected by moving the coned member 31 away from the ring 38 and externally coned flange 51. The internally and externally coned member 31 is moved away from the ring 38 and flange 51 by the pins 44, yoke 45 and connections to the stop mechanism of the machine hereinbefore described.

To guard against the thread being broken, when the main take-up starts to draw thread from the supply, due to the sudden pull on the thread having to overcome the inertia of the ten- Y sion wheel and its associated parts and the spring 64 is connected is given a movement in the direction in which it is moved by rotation of the tension wheel as the main take-up commences to draw thread from the supply. This movement of the shaft 59 is effected by the engagement of an adjustable screw I with the lug 13 extending from the collar I4 which is secured on the shaft 59, as hereinbefore described. The screw I00 is carried by a ing IOI extending from a pinion I02 rotatably mounted on the shaft 59 and the pinion is engaged by a gear segment I03 formed on an arm I04 which is secured to a shaft I05 rotatably mounted in bearings on the bracket 30.

The shaft I05 has secured on it an arm I06 (Figure 1) which is connected by a rod II" to an eccentric strap surrounding an eccentric secured to the cam shaft of the machine. The eccentric is arranged on the cam shaft so that just as, or

slightly before, the main take-up commences to draw thread from the supply, the screw I 00 is moved into engagement with the lug I3 on the collar 14 and causes the shaft 59 to begin to move in the direction in which it is subsequently moved by rotation of the tension wheel 34 when the main take-up is drawing thread from the supply so that the inertia of the tension wheel and its associated parts and the inertia of the spring 64 do not have to be overcome by the pull on the thread as the main take-up commences to draw thread from the supply. The screw I00 only engages the lug I3 for a short time and then moves away from. the

lug, the lug continuing to be moved in the direction in which itwas moved by the screw as the main take-up draws thread from the supply and when the tension wheel is returned by the spring 64, the screw I00 is out of the way of the lug so that the lug can engage the plunger 75.

The nature and scope of the invention having been indicated, and a machine embodying the several features of the invention having been spe ciflcally described, what is claimed is:

l. A chain stitch shoe sewing machine having, in combination, stitch forming devices, a thread tension wheel located at the back of the machine. a spring to restrain the rotation of the tension wheel, means acting in timed relation to the-stitch forming devices for connecting and disconnecting the wheel and spring during each stitch-forming cycle, means extending to the front of the machine conveniently accessible to the operator for adjusting the tension of the spring, and. an indicating device visible to the operator while at the front of the machine and actuated by said adjusting means for indicating the amount of tension placed on the spring.

2. A chain stitch shoe sewing machine having, in combination, stitch forming devices, a thread tension wheel located at the back of the machine, a spring to restrain the rotation of the tension wheel, means acting in timed relation to the stitch forming devices for connecting and disconnecting the wheel and spring during each stitch forming cycle, means extending to the front of the maadjusting the tension of said spring comprising a longitudinally movable rod, a tension indicat ing scale visible to the operator while at the front of the machine, apointer cooperating with the scale, and connections between the rod and the pointer for actuating the pointer to indicate the amount of tension placed on the spring.

3. A sewing machine having, in combination, stitch forming devices, a thread tension wheel, a rotatable shaft, a helical spring to restrain the rotation of the shaft, a flexible connection from one end of the spring to the shaft arranged to be wound on the shaft during its rotation. and means acting in timed relation to the stitch forming devices for connecting and disconnecting the wheel and shaft during each stitch forming cycle.

4. A sewing machine having, in combination, stitch forming devices, a thread tension wheel, a rotatable shaft, a helical spring to restrain the rotation of the shaft, a flexible connection from one end of the spring to the shaft arranged to be wound on the shaft during its rotation, means acting in timed relation to the stitch forming devices for connecting and disconnecting the wheel and shaft during each stitch forming cycle, and means connected to the other end of the spring for adjusting the initial tension of the spring.

5. A sewing machine having, in combination, stitch forming devices, a thread tension wheel,

a rotatable shaft, a helical spring to restrain the rotation of the shaft, a flexible connection from one end of the spring to the shaft arranged to be wound on the shaft during its rotation, means acting in timed relation to the stitch forming devices for connecting and disconnecting the wheel and shaft during each stitch forming cycle, means extending to the front of the machine conveniently accessible to the operator for adjusting the tension of the spring comprising a longitudinally movable rod, 2. connection between said rod and the other end of the spring, a tension indicating scale visible to the operator while at the front of the machine, a pointer cooperating with the scale, and connections between the pointer and said rod for actuating the pointer to indicate the amount of tension placed on the spring.

6. A chain stitch shoe sewing machine having,

' in combination, a hook needle, a looper, a main take-up acting while the needle is in the work, a spring pressed auxiliary take-up, a thread tension wheel, a spring to restrain the rotation of the wheel, means for connecting the wheel and spring during the take-up action of the takeup, means for locking the wheel from rotation during the loop drawing stroke of the needle, and a stop on the main take-up arranged to engage the auxiliary take-up during the take-up action of the main take-up.

7. A sewing machine having, in combination, stitch forming devices, a thread tension device, including a member movable with the thread as it is drawn from the supply, a spring yieldingly holding said member against movement, and means in addition to the thread for initiating the movement of said member in the direction in which it is moved by the thread.

8. A sewing machine having, in combination, stitch forming devices, a thread tension wheel, a rotatable member, a spring yieldingly holding the member from rotation, means for clutching and unclutching the tension wheel and member during each stitch forming cycle to cause the member to be rotated with the wheel. against the force of the spring by a pull on the thread and to be returned independently of the wheel, and power actuated connections, for initiating the rotation of said member in the direction in which it is moved by the thread.

9. A chain stitch shoe sewing machine having, in combination, a hook needle, a looper, a main take-up acting while,the needle is in the work, an auxiliary take-up, a spring connected to the auxiliary take-up to exert a yielding strain on the thread during the first portion of the loop drawing stroke of the needle, a spring pressed member arranged to be engaged by the auxiliary take-up during the latter portion of the loop drawing stroke of the needle, a thread tension wheel, a spring to restrain the rotation of the wheel, means for connecting the wheeland spring during the take-up action of the main take-up means for locking the wheel from rotation during the loop drawing stroke of the needle, and means for preventing yielding movement of the auxiliary take-up during the take-up action of the main take-up. v

10. A chain stitch shoe sewing machine having, in combination, a hook needle, a looper, a main take-up acting while the needle is in the work, a main take-up lever, an auxiliary take-up, a spring pressed auxiliary take-up lever, a spring pressed arm mounted coaxially with the auxiliary take-up lever arranged to be engaged by the auxiliary take-up lever during the latter portion of the loop drawing stroke of the needle, a thread tension wheel, a spring restraining the rotation of the wheel, means for connecting the Wheel and spring during the take-up action of the main take-up, means for locking the wheel from rotation during the loop drawing stroke of the needle, and a stop on the main take-up lever arranged to engage the auxiliary take-up lever and prevent yielding movement of the auxiliary take-up during the take-up action of the main take-up.

FRED RICKS. HAROLD ERNEST ELLIO'I'I'. FRANK COLEMAN CHOICE.

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