US1191747A

US1191747A - Shoe-sewing machine.

Info

Publication number: US1191747A
Application number: US72857912A
Authority: US
Inventors: Laurence E Topham
Original assignee: United Shoe Machinery Co AB
Current assignee: USM Ltd; United Shoe Machinery Co AB
Priority date: 1912-10-30
Filing date: 1912-10-30
Publication date: 1916-07-18
Anticipated expiration: 1933-07-18

Description

L. E. TOPHAM.

SHOE SEWING MACHINE.

APPLICATION FILED on. 30. 1912.

1,191,747. Patented July 18, 1916.

9 SHEETS-$HEET 2 I I 1 1 l I l I ll lnes'sesx [It vezzlan:

L. E. TOPHAM.

SHOE SEWING MACHINE.

APPLICATION FILED OCT-30.1912.

Patented July 18, 1916.

9 SHEETS-SHEET 3- JitUitZOi MW 7 75 W L. E. TOPHAM.

SHOE SEWING MACHINE.

APPLICATION men OCT. 30. 1912.

Patented July 18, 1916.

9 SHEETS--SHEET 4.

L. E. TOPHAM.

SHOE SEWING MACHINE.

APPLICATION FILED OCT- 30.19M-

Patented July 18, 1916.

L. E. TUPHAM.

SHOE SEWlNG MACHINE.

APPLICATION FILED OCT. 30. 1912.

Patented July 18,1916.

L. E. TOPHAM.

SHOE SEWING MACHiNE.

I APPLICATION FILED OCT. 30. 1912. 1,1 9 1 ,747. Patented July 18, 1916.

SSHEETS-SHEET 1.

L. TOPHAM. SHOE SEWING MACHINE. APPLICATION man OCT. 30. 912.

Patented July 18, 1916.

9 shins-such a.

a i i g l I L. E. TOPHAM.

SHOE SEWING MACHINE.

APPLICATION HLED 00130. 1912.

Patented July 18, 1916.

9 SHEETS-HEET 9 [lave/ita UNITED STATES PATENT OFFICE.

SHOE MACHINERY COMPANY, OF PATERSON, NE\V JERSEY. A CORPORATION OF NEW JERSEY.

SHOE-SEWING MACHINE.

Specification of Letters Patent.

1,191,717. Patented July 18,1916.

Application filed October 30, 1912. Serial No. 728,579.

To all whom it may concern:

Be it known that I, LAURENCE F. T OIHAM, a citizen of the United States. residing at Swampscott, in the county of Essex and State of Massachusetts, have invented certain new and useful Improvements in Shoe- Sewing Machines; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

The invention relates to sewing machines, and more particularly to curved hook needle sewing machines for sewing inseams of boots and shoes. In machines of this class during a cycle of operations of the machine in sewing a seam, starting with the needle in retracted position with a loop of thread held in its hook, the needle advances through the previously formed loop and through the materials, and after it has reached its advanced position the thread is laid in the hook of the needle by the looper. When the needle retracts, a loop of thread is drawn through the material and through the preceding loop which, when the needle advanced, lay about the shank of the needle. In order that the shoe may be removed when the scam has been completed and another shoe placed in position to be sewed, it is essential that the. needle be retracted out of engagement with the work. Before the shoe can then be removed, the loop of thread last t'ormcd must be removed from the barb ot' the needle. In order to tree the last loop from the barb of the needle and bring the needle to rest out of engagement with the work, in the machines heretofore devised, it has ordinarily been necessary for the operator to manipu late either the shoe or the machine. Certain automatic mechanisms have been devised tor accomplishing these results by arresting the forward movement of the machine when the needle has executed at least a portion of its work penetrating movement, and then reversing the direction of movement of the main driving shatt ot the machine and thereafter causing the shaft to come to rest when the needle is retracted out of engagement with the work.

The primary object of the present invention is to produce a curved hook needle inseam shoe sewing machine provided with mechanism for placing the thread and the parts of the machine in such a condition as to permit the ready removal of the shoe from the machine and the placing of another shoe in position to be sewed. without reversing the rotation of the main shaft of the machine.

\Yith the above object in view, the invention contemplates the provision in a machine of this class of mechanism to tree the last needle loop from the stitch t'orming devices during the forward rotation of the main shaft and thereafter to arrest the torward rotation of the main shaft and stop the machine with the needle in retracted position out of engagement with the work. In the preferred embodiment of the invention the last needle loop is i vcd from the stitch forming devices by rendering the loopcr inactive during the last cycle of operations before the main shaft is brought to rest.

The machine is provided with mechanism for advancing and retracting the welt guide during each cycle of opcrations. and a further tcaturc ot the invcinion contemplates the provision of means tor causing an increased retracting movement to be imparted to thc welt guide as the torward rotation of the main shaft is arrcstcd. By this provision the welt guide is brought to a position such that it present no obstacle to the rcady rcnioval ot the shoe or the inscrtion of anothcr shoe in the machinc.

Another fcaturc ot the invention contemplates the provision of mcans acting auto-- matically to actuate the tension dcvi c to rclcasc thc tension on the thread as the lorward rotation of the main shaft i allc lcil. to allow the removal of the work from thc machine.

Further features of the invention consist of certain constructions. arrangements and combinations of parts. the advantages of which will be obvious to onc skilled. in thc art ll'Ulll the following dcsci'ii tion.

The various t'caturcs ot' the invention will be radily understood from an inspection of the accompanying drawings and the following dctailcd dcscription of thc mechanism illustrated thcrcin.

In the drawings. l igurc l is a sidc clcvation of the licad ot' a \\clt and turn shoc sewing machine embodying the 'l'caturcs ot' the invention in their prcl'crrcd forms. illustrating the parts of the machine in the positions which they occupy during the sewing operation; Fig. 2 is a plan of a portion of the head of the machine, showing the parts in the positions which they assume after the 7 machine has been brought to rest at the completion of the sewing operation, with a part of the casing broken away and parts of the mechanism shown in section; Fig. 3 is a side elevation of a portion of the machine illustrating particularly the mechanism for actuating the looper and the mechanism for rendering the looper inactive, showing the parts in the positions which they assume after the treadle has been released to stop the machine, butbefore the machine has been brought to rest: Fig. 1 is a side elevation of a. portion of the machine illustrating particularly the mechanism for actuating the welt guide, the parts being shown in the positions which they occupy during the sewing operation; Fig. 5 is a side elevation of the mechanism illustrated in Fig. 4, showing the parts in the positions which they occupy when the machine has been brought to rest; Fig. (i is a side elevation of the mechanism illust ated in Fig. 3, showing the parts in the positions which they assume when the machine has been brought to rest; Fig. 7

a view in vertical section of the mechanism on the line 8% of Fig. 6; Fig. .l is a rear 'elevation of the mechanism illustrated in Fig. 4, together with a portion of the mechanism for arresting the rotation of the shaft; and Fig. 10 is a side elevation of the complete machine.

In the drawings, the invention is illustrated as embodied in a welt and turn shoe sewing machine for sewing the inseams of boots and-shoes, such as shown and described in the patent granted to Andrew Eppler, No. 1,108,560, dated August 25, 191i. This machine is provided with a curved hook needle 1, a looper i, a thread finger 3, a welt guide 4 and a hack gage 5, aml a feed point and channel guide not shown, and these devices are operated through suitable connections by cams ca rricd by the ma in shaft (3 of the machine. As is usual in this type of machine the main shaft makes one revolution for each cycle of operations performed by the stitch forming and work feeding devices. During the sewing operation, the machine is driven through a. belt pulley 7 secured to the end of the main shaft and connected by a driving belt 8 with a pulley 9 mounted upon the base of the machine. The pullcy 9 is connected by means of the bevel gears 10 with a sleeve 11 mounted on the driving shaft 12 and carrying one member 13 of the main driving clutch. The driving shaft carries the other member 11 of the clutch and also carries the driving pulley 15, through which motion is imparted to the driving shaft. The engagement of the members of the driving clutch is controlled through a treadle 16 connected with the clutch operating wedge 17. hen the treadle is depressed, the members of the driving clutch are forced into engagement and the machine is driven at a speed de pending upon the pressure which the op rator applies to the trcadle. When the treadle is released, the clutch members are disengaged, thus disconnecting the main shaft of the machine from the driving haft. The upward movement of the treadle when itis released also throws into operation the mechanism which brings the machine to rest with the parts in proper position for the removal of the slice. This ima'hanisni in the construction shown comprises a friction clutch consisting of the clutch members 18 and 1f). The clutch member 18 is formed on a spiral gear in which loosely mounted on the cam shaft '5 and is driven at a constant slow speed, in the same direction as the direction of rotation of the main shaft during the sewing operation by a spiral pinion 21 secured to a shaft 2; The shaft 22 is continuously driven from the driving pulley 15 through a belt 23 passing over a pulley formed on the hub of the pulley 15 and over a pulley llsecured to the shaft 22. The other member ltlof the'clutch is formed on a flange 2.) projecting from a sleeve 26 which is loosely mounted upon the cam shaft (3. The sleeve 26 is free to slide hingitudinally on the shaft but is connected to rotate with the shaft by means of a block 27 secured to the pulley T and arranged between lugs 28 projecting radially from the sleeve 20. The sleeve is held normally in position with the clutch members out of engagement by a spring 2) arranged in a recess in the block 27 and interposed between the bottom of the recess and the head of abolt which carries a plate 30 engaging the lugs The clutch member 18 is drlven-at a constant speed, as stated above, and the speed of this member is very slow compared with the speed of rotation of the cam shaft of the machine during the sewing operation. 'lhcreforc when the clutch members 18 and 11) are engaged, they act as a friction brake to absorb the energy due to the momentum of the cam shaft and of the machine until the speed of rotation of the main shaft is the same as that of the clutch member 19. After this has occurred. the clutch member 18 acts as a driving member for the clutch member 1!.) and the main shaft, and themain shaft is thereby rotated in a forward direction at slow speed until the stopping devices act to bring the main shaft to rest with the needle and other parts of the stitch forming mechanism in the proper position for the removal of the shoe. The stopping devices are constructed and arranged so that. the

clutch members

18 and 19 are engaged and disengaged at definite points in a cycle of operations of the machine and after the clutch members are engaged. the main shaft executes a definite movement before it is brought to rest. The mechanism for engaging and disengaging the members of the clutch at the proper time in the rotation of the main shaft comprises a cam groove 32 formed in the sleeve 26 and engaged by a roll on one arm of a bell crank lever 33. The other end of the bell crank lever is provided with a recess 31 adapted to receive a locking pin 35 which is normally held out of engagement with the lever so that during the normal running of the machine the lever is oscillated idly by the cam. The locking pin is mounted in the end of a slide 36 which is held in normal position by a spring 37. The spring surrounds a bolt or rod 38 extending from the rear of the slide and is interposed between a shoulder on the slide and the inner end of an ad justable screw threaded sleeve :32) through which the rod 38 passes, the sleeve being threaded into a suitable portion of the frame. The rod 38 is held in position to maintain the spring under compression by the engagement of a nut 39" threaded on the rod with an arm 40 projecting from a fixed bracket on the frame of the machine, the arm being provided with an aperture through which the rod passes. The locking pin is forced in a direction to engage it with the bell crank lever by a spring 41 and the lower end of the pin is connected with the trcadle 16 so that the pin is held down out of engagement with the bell crank lever so long as the treadle is depressed and the driving clutch is acting to drive the main shaft of the machine. A latch 42 is also connected with the lower end of the locking bolt and is arranged to engage a shoulder 43 on the slide 36 and hold the locking bolt in its lower position until the treadle has been raised sufficiently to allow the locking bolt to engage the recess in the arm of the bell crank lever. In the construction shown. the latch 42 is loosely pivoted on the rock shaft 41 and is connected with the shaft by a pin projecting through a slot in the hub of the latch. The rock shaft 44 is mounted in a block it secured on the lower end of the locking bolt and carries an arm 47 which is connected by a link 4% with the treadle .lti. \Vhen the trcadle is depressed. the rock shaft it turns until the latch 42 brings up against the slide 36. and then during the continued downward movement of the treadlc the locking bolt is drawn down against the tension of its sprin This carries the latch 42 below the shoulder 43. \Vhen the treadle is rel *ased, the latch 42, prevents the upward movement of the locking pin and the rock shaft 11 is rocked until the pin strikes the end of the slot in the hub of the latch and swings the latch outward. thus disengaging it from the shoulder 1 When this takes place the spring forces the pin upward against the under side of the bell crank lever. and when the hole in the lever registers with the pin, the pin snaps up into the hole, thus connect ing the lever with the slide it The cam IL is so timed that the hole in the end of the -cll crank lever is brought into position to register with the locking pin at the proper time in the cycle of operations of the stitch forming mechanism. When the pin is engaged with the bell crank lever, the lever is held from movement about its pivot, and the cam 32 acting on the roll carried by the lever shifts the clutch sleeve 26 to bring the

members

18 and 19 of the clutch into engagement. 'hen the lever and slide 36 are locked together by the locking pin, the movement of the lever is resisted by the spring 257, and the force with which the members of the friction clutch are pressed together will depend upon the tension of the spring. In the construction shown, the parts are so timed and controlled that the locking bolt is engaged with the lever and the friction clutch engaged while the needle is retracted, and the forward rotation of the main shaft is continued thereafter until the needle has penetrated the work, and then retracted out of engagement with the work, at which time the clutch members are disengaged and the rotation of the shaft is arrested, thereby bringing the parts of the machine to rest. \Vhen the

clutch members

18 and 19 have been engaged by the action of the cam 32. the

main shaft 1s first slowed down to the slow speed of the member 18 of the clutch by the braking action of the members of said clutch, and the rotation of the main shaft is then continued in a forward direction at slow speed for substantially a complete revolution, or until the shaft again arrives at a point where the cam acted to engage the members of the clutch, when the opposite portion of the cam from that which caused the engagement of the clutch members causes the clutch members to be again disengaged. Simultaneously with the disengagement of the clutch members, the motion of the cam shaft is arrested by a suitable brake so that the needle executes substantially a full cycle of its movement after the friction clutch is engaged and the needle is brought to rest in retracted position out of engagement with the work. The main shaft is therefore brought to rest with the needle in its rctracted position and the other parts of the stitch forming mechanism in such positions that they do not interfere with the removal of the shoe. hen the friction clutch is disengaged. the forward movement of the main shaft is finally stopped by a friction brake which is'applied to a brake disk on the main shaft of the machine. In the construction illustrated in the drawings, the brake consists of a brake strap 49 arranged to engage the surface of a brake disk 50', the forward extremity of which strap is attached at a fixed point on the framework of the machine, and the rear extremity of which is secured tn the vertical arm of the lever 49 pivoted on a shaft 50 securt in the machine frame.

As above described the machine is brought to rest with the needle in retracted position during the forward rotation of the main shaft and during a forward cycle of movement of the machine, and mechanism is pro vided for rendering the looper inactive during the last cycle of movement of the needle before the main shaft of the machine is brought to rest, so that the needle is retracted while its hook is empty, and is free of thread when it is brought to rest out of engagement with the work. In the present embodiment of the invention this mechanism is actuated in timed relation to the parts of the machine and to the devices for arresting the forward rotation of the shaft, by suitable connections from the mechanism for engaging the members of the braking and slow speed forward driving mechanism, and for disengaging said members and stopping the machine. In the construction illustrated in the drawings the looper is provided with a shank which is received in a cylindrical socket formed in the lower end of an arm 51, the connection between the looper shank and the arm being such that the looper can be adjusted vertically. The shank of the looper is held in the arm by means of a clamping screw 52. The arm 51- is pivoted midway its length to a block 53 secured to the forward end of a cam actuated slide 54. The slide 54: is arranged above the needle to reciprocate in a plane parallel with the plane of the needle, so that the reciprocating movements of the slide impart forward and rearward 1novc ments to the looper. The movements of the looper at right angles to the plane of the needle are produced by oscillating the arm 51, the movements of the looper due to the reciprocation of the slide and the oscillation of the arm acting to carry the thread around the needle and lay it in the barb. The upper end of the arm 51 provided with a socket in which a rod 55 is received. This rod is provided at its upper end with a socket or bearing which receives a rod 56 scoured to an arm 57 projecting from a rock shaft 58 arranged parallel with the slide 54.

-The rod 55 is free to slide in the socket in the upper end of the arm 51, and the rod 56 is free to slide in the socket in the upper end of the rod 55, so that the arm 51, can be oscillated from the rock shaft 58 and at the same time the slide 54 can be reciprocated. The shaft 58 is provided with a downwardly projecting arm 59 at its rear end which is provided with a roll engaging a cam on the cam shaft of the machine.

In the illustrated embodiment of the invention the looper is rendered inactive by causing the looper to operate in a single plane only during the last cycle of movement of the needle before the main shaft ol the machine is brought to rest. To this end the slide 54 is constructed of independently movable parts (30 and 61, of which the part 60 is arranged to slide within the part 61, as illustrated particularly in Figs. 1, 3 and 7. The parts (30 and 61 he lc r slide 5% are connected by a kage or toggle mechanism consisting of ie links and 63. \Vhen the machine is l ,unning normally the linkage (iii-63 is maintfiined in the posh tion illustrated in Fig. 1, so that the two parts of the looper slide move forwardly and rearwardly in unison, thereby imparting the proper forward and rearward move ments to the looper. hen the looper is thrown out of action, the movement of the rear cam actuated part 61 of the looper slide is absorbed in the relative angular movement of the parts of the linkage (vi- 6 3, so that substantially no forward and rearward movements are imparted to the part 60 of the looper slide. The linkage (32-433 is maintained in the position illustrated in Fig. 1 during the normal operation of the machine by a tilting pin (it mounted upon an rm 65 attached to a rock shaft 66 jour naled in a bearing in av bracket (37. The link (33 of the linkage carries a pin 68, to the end of which is attached a sleeve (39 which is arranged to slide on the t ting pin 64. During the normal operation of the machine the tilting pin (it is maintained in a position substantially parallel with the slide 51, thereby maintaining the linkage (32---(33 in the position illustrated in Fig. 1, and causing the two parts of the looper slide to move in unison. The looper is thrown out of action by tilting the pin til into the position illustrated in Fig. 3. hen the tilting pin occupies this position, and the part 61 of the looper slide is moved forwardly undcr the action of the cam, the sleeve (33), guided by the tilting pin, moves downwardly at an angle with relation to the looper slide, carrying the linkage (32 33 to the position illustrated in Fig. 3, thereby absorbing the forward movementof the. rear part of the looper slide in the angular movement of the parts of the linkage, so that substantially no forward movement is imparted to the looper. \Vhen the part (31 of the, looper slide is moved rearwardly, the linkage is again brought to the position illustrated in Fig. 1. It will therefore be observed that while the tilting pin is maintained in the position illustrated in Fig. 3,

substantially no forward and rearward movements will be imparted to the looper. In the construction illustrated the tilting pln is moved from a position parallel with the looper slide to the position illustrated in Fig. 3 at the time when the

members

18 and 19 of the friction cl-utch are engaged by suitable connections withthe rod 38.

block 75 carried by a pin 76 whichis mounted in a block '77 adj ust'ably carried between nuts 39*" and 7S u'pon the outer end of the rod 38. \V hen the members of the friction clutch are engaged by the cam 32, the rod 38 is moved outwardly through the sleeve 39. This movement of the rod through the connections described operates to tilt the i tilting pin (it into the position illustrated in Fig. 3. The machine is timed so that this occurs when the part 61 of the looper slide is retracted, and the parts are so arranged that at this time the axis of the pin 68, which carries the sleeve 69, and the axis of. the rock shaft (36 arein alincment; therefore the tilting of the pin does not affect-the relative positions. of the. links (52 and'63. V hen. however, the rear part of the looper slide advances, the nmvenwnt of this part of the slide is absorbed in the relative angular movement of the-parts of the linkage, as above described, but at each retracting movement of the rear member of the looper slide the linkage is restoredto the position illnstrated in Fig. 'ben the cam 32 operates to disengage the members of the friction clutch, at which point the shaft is brought to rest. the rod -18 is returned to its initial position illustrated in Figs. 1 and 6. '.his movement of the rod restores the tilting pin to the position illustrated in Fig. l' through the mechanism described. so that when the machine is brought to rest. the. parts'of the looper mechanism are in posi tion ready to start their normal operation when the machine is started.

The merhanism with which the machine is provided for applying the brake sl rap -lto the surface of the brake disk which it. is

arranged to engage comprises a linkage or toggle consisting ol the links Ti and H). of which the link Ti is romu-rled lo the upper extremity of the lever l The link SU is provided with a slot at its l'orward extremitv which l'('('(i\('s a pin 51 carried by the upper end of an arm 32 on the level 72-T l. The link so is provided with an arm fi l which is (tollluriwl by a comparatively light. tension spring Hl with the arm H2. When the machine. is performing its normal operation the. linkage T -S(l is maintained in the position illustrated in Fig. l by the pressure ofthe pin 81 against the end of the slit in the link80, the tension of the spring 84 not being suflicient tostraighten the linkage. At this time the coiled sprmg 8.3 surrounding the hub of the lever 49 operates to maintain the brake stra in a slacken -d condition, as shown in Fig. 1. When the rod 38 moves to the right in F ig. 1 upon the engagement of the members of the fric tion clutch, the forward movement of the pin 81in the slot in the link relieves the pressure upon the forward portion of the linkage 7980, and the coiled spring '84 then acts to straighten the linkage, as shown in Fig. 3. \V hen the rod 38.is returned to the left upon the-separa'tionof, the members of the friction clutch, thearm 82 of the lever 72-71 is moved .to the left (Fig. '1), and the engagement of the pin-81 inthe end of the slot in the'link'80 forces the-linkage 79-80 to the left, thereby moving the lever 45) in a. direction to apply the brake strap 49 to the surfaceof the brake disk 50. The forward movement of the main shaft, which is then rotating at slow speed is thereby quickly arrested withmttashock or jar.

The tension devices of the machine illustrated in the drawings are of wellskn'own construction, and comprise a tension wheel at the rear of the machine, a brake disk 86 fast upon the shaft of t-lie't ension. wheel, a

friction brake :shoe S7- bearing upon the pe-; riphery of the brake disk, :1.- pivoted lever 88 to one end of which thgbrake shoe is connected, and a spring pressed rod 89 connectcd to the otherend of the lever. In order that the tension may be released when the machine is brought-to rest, the lever 49 is provided with an arm 90, and to this arm is pivotally connected the upper end of a rod 91 which extends downwardly through a hole in the end of the brake shoe carrying lever 5 and is provided with an adjustable nut J2 arranged to engage the brake shoe. carrying lever to move the brake shoe from the l'ricl ion disk. The. rod i l is pressed upwardly b v means of a coiled spring 93. When the lever i fis moved to the left to appl v the brakestrap 4! to the surfare. of

the. ram disk. the arm is depressed, thereby releasing the tension.-

'lhc welt guide. r. is mounted upon the lower end of a pivoted welt guide carrying arm fll whirli is connected by a link 95 to the. welt guide slide 96. The welt guide is \ieldingl v advanced b a roiled spring 97 engaging a pin on the. welt guide slide in the usual manner, and is retracted at the proper time in the operation of the machine b a lever E i ronnerted by a link 93 with a ('lnlrli box surrounding the slide, and provided with the usual clutch mechanism for engaging the slide. The back rest 5 is carried on the forwa rd extremity of the back rest slide 100 which is moved forward by the usual spring 101. The mechanism for locking the back rest and welt guide slides is of the usual construction, and comprises clutch rolls 102 and 103, arranged to engage suitable friction surfaces on the welt guide and back rest sliderespectively, a wedge shaped supporting member 104 for the rolls pivoted to the arm of the cam actuated lever 105 provided with an arm 106 carrying a cam roll which engages a cam on the cam shaft of the machine, which cam actuates the lever to release the slide. The lever is actuated to lock the slides by a tension spring 107 connected at one extremity with the arm 105 of the lever, and at the other with a fixed point on the machine frame.

The welt guide of the machine is advanced and retracted during each cycle of operations in substantially the same manner as in the machine of the Eppler patent referred to above. In the present invention, however, mechanism is provided for causing an increased retracting movement to be imparted to the welt guide as the forward rotation of the main shaft of the machine is arrested to permit the ready removal of the shoe and the insertion of another shoe in the machine. The mechanism for actuating the welt guide is illustrated particularly in Figs. 1, 4 and 5. The lever 97 is pivoted at 108 on the machine frame, and is provided with a rearwardly extending arm 109. An arm 110 is pivoted at 111 to the arm 109 of this lever, and is provided at its outer extremity with a cam roll which engages a cam on the cam shaft of the machine. A linkage or toggle consisting of

links

112 and 113 connects the arm 109 of the lever 97 with the vertical arm of the lever 49, and the arm 110 is connected with the central joint of said linkage by a link 114. The position of the welt guide mechanism when the machine is in normal operation is illustrated in Fig. 4:, the parts being shown in said figure in the positions which they assume when the welt guide is advanced. It

- will be noted from an inspection of this figure that when the vertical arm of the lever 49 is in forward position, the oscillatory movements of the arm 110 cause very little change in the relative angular positions of the

links

113 and 114, the arm 110,

links

113 and 114, and lever 97 all oscillating in unison substantially as one. Referring to Fig. 5, it will be seen that when the vertical arm of the lever a9 is in back position, the oscillatory movement of the arm 110 from the position in which it is shown in Fig. 4, to that in which it is shown in Fig. 5, will cause an angular movement of the

links

113 and 114 such as to diminish the angle between said links. The lever 97 will thereby be operated to retract the welt guide 48 with the arm 46.

to a position to the rear of its normal retracted position when the machine is brought to rest, so as to permit the shoe to be easily removed from the machine and another shoe to be placed in position to be sewed.

At the completion of the sewing of a scam the thread leading from the thread handling devices to the shoe is severed by a suitable knife, and the free end of the thread is in serted between the gripping devices which hold the free ends of the thread during the formation of the first stitch. Since the machine is brought to rest with the needle in retracted position, when the machine is again started into operation the takeup immediately begins its loop drawing stroke. This action of the takeup, if exercised while the tension is'app'lied to the supply end of the thread, would operate to draw the free end of the threadfrom the gripping devices and interfere with the proper formation of the first stitch. It is therefore desirable that the tension be maintained in released condition until after the takeup has completed its first loop drawing stroke. It is however desirable upon starting the machine that the brake strap 19 be slackened so that it will not frictionally engage the coacting surface of the brake disk. In order to slacken the brake strap when the treadle is depressed to start the machine, without causing the tension tobe applied, the brake strap is connected with the lever 4 9 by means of a rotatable eccentric 115 ,carried by the shaft 116 which connects the brake strap with the lever. An arm 117 is attached to the shaft 110 and is provided at its extremity with a slot which receives the end of the pin 118 which connects the link hen the treadle is depressed to start the machine, the engagement of the pin 118 in the slot in the arm 117 causes said arm to be actuated to rotate the eccentric 115 and thereby slacken the brake strap 49. V hen the treadle is released the arm 117 is actuated in the opposite direction, thereby rotating the eccentric 115 in a direction to tighten the brake strap. This movement of the eccentric is, however, not sullicient to engage the brake strap with the surface of the brake disk, since there is considerable slack in the brake strap at this time. After the takeup has completed its loop drawing stroke, the linkage 7980 is broken so as to permit the spring 85 to op crate the lever 40 in a directionto permit the tension to be restored to the supply end of the thread, and to return the parts of the welt guide mechanism to their normal positions. It will be noted from an inspection of Fig. 5 that when the machine has been brought to rest, the link 79 lies against a collar carried by the cam shaft of the machine, which collar forms a stop to limit the movement of the link 79 when the link age is straightened. After the takeup has completed its loop drawing stroke the link 79 is lifted to break the linkage 79--S0 by a cam 119 carried by the cam shaft. When the linkage is broken the lever 49 is moved to the right under the influence of the spring 85, thereby lifting the arm 90 to permit the tension to be restored to the thread, and restoring the parts of the welt guide actuating mechanism to the position illustrated in Fig. 4. This movement of the lever 4-9 also causes the brake strap to be completely slackened.

Having explained the nature and object of the invention, and particularly described one form of machine in which it may be embodied, what is claimed. isz

1. A chain stitch shoe sewing machine, having, in combination, stitch forming dc vices including a hook needle and a looper, a main shaft from which said devices are operated, and mechanism to render the looper inactive during a forward cycle of movement of the machine and to cause the main shaft thereafter to come to rest with the needle in retracted position out of engagement with the work.

2. A chain stitch shoe sewing machine, having, in combination, stitch forming devices includinga hook needle and a looper, a main shaft from which said devices are operated, and mechanism to render the looper inactive during the forward rotation of the shaft and thereafter to arrest the forward rotation of the shaft and thereby the movements of the parts of the machine when the needle is in retracted position out of engagement with the work.

3. A chain stitch inseam shoe sewing machine, having, in combination, stitch forming devices including a hook needle and a looper, a \vcll guidc, means to advance and rctract the wclt guidc during each cycle of operation, a. cam shaft mechanism for causing the needle to retract while its hook is empty and comc to rcst out of cngagcmcntwith the work during the forward rotation of tlic cam shaft and mcans opcratcd during the forward rotation of thc cam shaft for importing an incrcascd rctracting movement to the wclt guide.

4.. An inscaln shoe scwing machine, having, in combination. stitch forming devices, a wclt guide, michanism for advancing and retracting tbc clt guidc during cach cycle of opcrat ions. a main shall, and mcans actuatcd by the fol ward movcmcnt of the shaft for causing all incrcascd rctracting movenicnt to be iln|artcd to thc \vcll guide to pcr mit the rcmmal and inscl'tion of the work.

An insc: m shoc sewing ma hine. having, in combnation, stitch forming dcviccs, a main shaft from wxhich Said deviccs are actuated, a welt. guide, means to advance and retract the welt guide during each cycle of operations, and mechanism for causing an increased retracting movement to be imparted to the welt guide as the forward rotation of the shaft is arrested to stop the machine.

6. An inseam shoe sewing macaine, having, in combination, stitch forming devices. a welt guide, mechanism for advancing and. retracting the welt guide during each cycle of operations of the machine, a tension device, a main shaft and mechanism actuated by the forward rotation of the main shaft of the machine to actu; '0 tie tension device to release the tension on the thread and to cause an increased retracting movement to be imparted to the welt guide to permit tlre removal and insertion of the work.

7. A chain stitch inseam shoe sewing machine, having, in combination, stitch forming devices including a hook needle and a looper, a welt guide, mechanism for advancing and retracting the welt guide during each cycle of operations of the machine, a tension device, mechanism to cause the needle to retract while its hook is empty and come to rest out of engagement with the work during a forward cycle of movement of the machine, and mechanism for actuating the tension device to release the tension and for causing an increased retracting movement to be imparted to the welt guide as the needle is brought to rest.

8. A chain stitch shoe sewing machine, having, in cc nbination, stitch forming de vices including a hook needle and a loopcr, means to operate the loopcr in a plane substantially perpendicular to the plane of the needle. a cam actuated slide for imparting movcnicnts to the loopcr in a plane substan tially parallel with the plane of the needle comprising indcpcmlcntly movable parts, a.

conncction between one of said parts and the loopcr. means to connect said parts so that they move in unison. and means to throw out said connecting mcans so that. substantially no movement is impartcdd the part of said slidc connected with the loopcr.

H. A chain stitch sboc sewing machine, having. in combination, stitch forming dc vices including a-hook needle and a loopcr, mcans to impart movcmcnts to the looper in a plane at right angles to the plane of the nccdlc. a cam actuated slide for imparting movements to thc loopcr in a plane parallcl with thc plane of the needle comprising indcpcndcntly movable parts, one of which is cam actnatcd. a conncction bctwccn the othcr of said parts and the loopcr. a linkage conncctiug said parts so that thcy opcratc in unison. and mechanism for causing the movements of the cam actuatcd part of the llll slide tobe absorbed in a relative angular movement of the parts of the linkageso that siibstantially no movement is imparted to the part of the slide connected with the looper.

10. A chain stitch shoe sewing machine, having, in combination, stitch forming devices including a curved hook needle and a looper, a cam actuated slide for imparting movements to the looper in a plane parallel with the plane of the needle comprising independently movable parts, one of which-is actuated by the cam, a connection between the other of said parts and the looper, a linkage connecting said parts, means to maintain the linkage normally in a relatively straightened condition comprising a tilting pin normally extending parallel with the direction of movement of the slide, a slide block arranged to slide on said pin and connected with the linkage, and mechanism for tilting the pin to cause a relative angular movement of the parts of the linkage during the movements of the cam actuated part of the slide so that substantially no movement is imparted to the part of the slide connected with the looper.

11. A shoe sewing machine, having, in combination, stitch forming devices, a main shaft from which said devices are actuated, a tension device, and positively operating means acting automatically to actuate the tension device to release the tension as the forward rotation of the shaft is arrested to stop the machine.

12. An inseam shoe sewing machine, having, in combination, stitch forming devices, a welt guide, means to advance and retract the welt guide during each cycle of operations, a tension device, a main shaft, means to arrest the forwardrotation of the shaft, and means acting automatically to actuate the tension device to release the tension and to cause an increased retracting movement to be imparted to the welt guide as the forward rotation of the shaft is arrested.

13. A chain stitch inseam shoe sewing machine, having, in combination, stitch forming devices including a curved hook needle, a looper, a welt guide, means to advance and retract the welt guide during each cycle of operations, a tension device, a main shaft, means to render the looper inactive during a forward cycle of movement of the machine and thereafter to arrest the rotation of the shaft when the needle is in retracted position out'of engagement with the work, and means acting automatically to actuate the tension device to release the tension and to cause an increased retracting movement to be imparted to the welt guide as the shaft is brought to rest.

14. An inseam shoe sewing machine, having, in combination, stitch forming devices, a welt guide, a. welt guide slide, a lever for actuating the slide, and mechanism for actuating the lever comprising a cam operated arm pivoted on the lever, a toggle connecting the arm with the lever, a second lever connected with the central joint of the toggle, means 'to maintain the second lever in one position during the normal operation of the machine, and means to change the position of the second lever upon stopping the machine to cause an increased retracting movement to be imparted to the welt guide before the machine is brought to rest. I p

15. A chain stitch shoe sewing machine, having, in combination, stitch forming fievices including a curved hook needle and a looper, a drive shaft from which said devices are actuated, braking and slow Speed forward driving mechanism for the shaft, means to throw said mechanism into action at a predetermined point in a cycle of operations and to throw said mechanism out of action and stop the machine, and means to render the looper inactive. i I

16. A chain stitch shoe sewing machine, having, in combination, stitch forming devices including a curved hook needle and a looper, a main shaft from which said devices are actuated, braking and slow speed forward driving mechanism for the shaft, means to throw said mechanism into operation and to throw said mechanism out ofoperation and stop the machine at a predetermined point in a cycle of movement of the machine, and means to render the looper inactive.

17. A chain stitch shoe sewing machine, having, in combination, stitch forming devices includinga curved hook needle and a looper, a main shaft from which said de vices are actuated, braking and slow speed forward driving mechanism for the shaft,

means to throw said mechanism into operation in a cycle of operations of the machine before the thread is laid in the barb of the needle, and to throw said mechanism out of operation and stop the machine when the needle is retracted out of engagement with the work, and means to render the looper inactive.

18. A chain stitch shoe sewing machine, having, in combination, stitch forming devices including a curved hook needle and a looper, a main shaft from which said devices are actuated, braking and slow speed forward driving mechanism for the shaft, means to throw said mechanism into operation and to throw said mechanism out of operation and stop the machine at predetermined points in a cycle of movement of the machine, and means to render the looper inactive.

19. -An inseam shoe sewing machine, having, in combination, stitch forming devices, a main shaft from which said devices are actuated, a tension device, a welt guide, means to advance and retract the welt guide during each cycle of operations, braking and slow-speed forward driving mechanism for the shaft, means to throw said mechanism into action and to throw said mechanism out of action and stop the machine, means to actuate the tension device to release the tension and to cause an increased retracting movement to be imparted to the welt guide as said mechanism is thrown out.

20. A chain stitch shoe sewing machine, having, in combination, stitch forming devices including acurved hook needle and alooper, a main shaft from which said devices are actuated, braking and slow speed forward driving mechanism for the shaft, means to throw said mechanism into and out of action, and means to render the looper inactive.

21. A shoe sewing machine, having, in combination, stitch forming devices, a takeup, a main shaft from which said devices are actuated, a tension device, automatically operating mechanism to actuate the tension device upon stopping the machine to release the tension, and means to cause the tension to be restored after the takeup completes its first loop drawing stroke upon starting the machine.

22. A chain stitch shoe sewing machine, having, in combination, stitch forming devices including a curved hook needle and a looper, a main shaft from which said devices are operated, mechanism including a timing cam to render the looper inactive during a forward cycle of movement of the machine and to arrest the rotation of the shaft and stop the machine with the needle in retracted position out of engagement with the work.

23. A chain stitch shoe sewing machine, having, in combination, stitch forming devices including a curved hook needle and a looper, a main shaft from which said devices are actuated. devices for arresting the forward rotation of the shaft at a predetermined point, and means to render the looper inactive at least a predetermined interval before the rotation of the shaft is arrested.

24. A chain stitch shoe sewing machine, having, in combination, stitch forming devices including a curved hook needle and a looper, a main shaft from which said devices are actuated, devices for arresting the forward rotation of the shaft at a predetermined point, and means including a timing device for throwing the arresting devices into action and for rendering the looper inactive at a predetermined point in a rotation of the shaft.

25. A chain stitch shoe sewing machine, having, in combination, stitch forming devices including a curved hook needle and a looper, a main shaft from which said devices are operated, mechanism to check the rotation of the shaft and thereafter to rotate the shaft at slow speed to stopping position, and means including a timing device for throwing said mechanism into action and for rendering the looper inactive at the same point in the rotation of the shaft.

26. A chain stitch shoe sewing machine, having, in combination, stitch forming devices including a curved hook needle and a looper, a. main shaft from which said. devices are actuated, devices for arresting the forward rotation of the shaft comprising means to check the rotation of the shaft and thereafter to rotate the shaft at slow speed to stopping position, mechanism including a timing device to throw said means into action and for throwing said means out of action and stopping the machine at predetermined points, and means controlled by the timing device to'render the looper inactive when said means are thrown into action.

27. A chain stitch shoe sewing machine, having, in combination. stitch forming devices including a curved hook needle and a looper, a main shaft from which said devices are actuated, devices for arresting the forward rotation of the shaft constructed to cause the shaft to execute at least a predetermined forward movement after said arresting devices are thrown into action before the shaft is brought to rest, and means including a timing device to throw the arresting devices into action and simultaneously to render the looper inactive.

28. A chain stitch shoe sewing machine, having, in combination, stitch forming devices including a hook needle and a looper, a main shaft from which said devices are operated and mechanism acting, when thrown into operation, to free the last needle loop from the stitch forming devices during the forward rotation of the shaft and to bring the shaft to rest in predetermined position with the needle in retracted position out of engagement with the work.

29. An inseam shoe sewing machine having, in combination, stitch forming devices, a welt guide, a welt guide slide, means including a toggle for actuating the slide to advance and retract the welt guide during each cycle of operations and to, retract the welt guide to the rear of its normal retracted position upon stopping the machine.

30. A shoe sewing machine, having, in combination, stitch forming devices, includ-. ing a hook needle and a looper, a main shaft from which said devices are operated, stopping devices for arresting the rotation of the shaft and means to render the 'looper inactive.

31. A shoe sewin machine, having, in combination, stitch aming devices, a tension device automatically operating mechanism to release the tension upon stopping the machine acting to maintain the tension in released condition until the takeup has completed its first loop drawing stroke upon starting the machine.

LAURENCE E. TOPHAM. Witnesses:

RUTH E. WARD, CHESTER E. ROGERS.

Copies of this patent may be obtained for five cents each, by addressing the "Commissioner of Patents, Washington, D. O.