US2905120A

US2905120A - Feeding mechanisms for sewing machines

Info

Publication number: US2905120A
Application number: US664385A
Authority: US
Inventors: Hacklander Hans
Original assignee: Singer Co
Current assignee: Singer Co
Priority date: 1957-06-07
Filing date: 1957-06-07
Publication date: 1959-09-22
Anticipated expiration: 1976-09-22

Description

Sept. 22, 1959 H. HACKLANDER FEEDING MECHANISMS FOR sawmc MACHINES 5 Sheets-Sheet 1 Filed June 7, 1957 INVEN TOR. Hans Hack/under w vwmq NW N- \.|"1w u. I- v 1 l l -l 1w m 0. 9. m WW QM w. m M. Q NN mm I E 4 8 2 mm i i1 Q p. W M I! w Q :1! W fi i! m .1. in twahfar ATTORNEY Sept. 22, 1959 H. HACKLANDER FEEDING MECHANISMS FOR SEWING MACHINES 5 Sheets-Sheet 2.

Filed June 7, 1957 INVENTOR. Hans Hack/under Z ZITTORNEY p 22, 1959 H. HACKLANDER 2,905,12@

FEEDING MECHANISMS FOR SEWING MACHINES 5 Sheets-Sheet Filed June '7, 1957 2 3 4 &

Fig. 3.

INVENTOR.

Hans Hack/under ATTORNEY Sept. 22, 1959 H. HACKLANDER FEEDING MECHANISMS FOR SEWI ENG MACHINES 5 Sheets-Sheet 4 Filed June 7, 1957 INVENTOR. Hans Hack/under BY yjfi j fl asud ATTORNEY Sept. 22, 1959 H. HACKLANDER FEEDING MECHANISMS FOR SEWING MACHINES 5 Sheets- Sheet 5 Filed June 7, 1957 INVENTOR. Hans Hack/under ATTORNEY Patented Sept. 22, 1959 I The Singer. Manufacturing Company, Elizabeth, N.J.,

a corporation of-New Jersey.

Application June 7, 1957,Serial No. 664,385

10 Claims; (Cl.-'112--212) The present invention relates to a feeding mechanism for sewing machines and panicutarlyto a four-motion type feeding mechanism;

In applicants copending application Serial No. 609,836 there is disclosed and claimed a sewing machine designed to accommodate a number ofdifierent attachment mechanisms and toward this end is designed to be provided with a pair of vertically spaced parallel attachment drive shafts which extend longitudinally of the bracket arm and which may be used individually or in combination. One of the primary objectsof the present invention is to provide a feeding mechanism and specifically a four motion feeding mechanism carriedby the bracket arm of the machine and operating on the upper surface of the work, which feeding mechanism is designed for use with a sewing machine as disclosed'in my above noted application Serial No. 609,836and which is designed to be ac tuated bythe same two-attachment drive shafts.

' It is a further object of this invention to provide a top four motion feeding mechanism for a sewing=machine, whichmechanism is relatively simple, economical,- dependable, efiicient and easy to operate and adjust.

" Having in mind thefabove and other objects that will be evident'from an understanding of this disclosure, the invention comprises the devices, combinations and arran ements ofparts as illustrated in the presently prefeired embodiment of theinvention whichis hereinafter set forth in such detail 'as' to enable those skilled in the art readilytounderstand thfunction, operation, construction and advantages ofitwhen read in conjunctionwith the accompanying drawings in which:

, Fig; l is a fragmentary vertical sectional'view longitudinally of a sewing machine embodying the present invention. p 7

Fig.2 is a horizontalsectional view longitudinally of the bracket arm of the sewing machine illustrated in Fig.1.

Fig. 3 is a vertical sectional view taken substantially entire lin 3 -3 of Fig. l. v

Fig. 4 is a fragmentary elevational view of the head end of the sewin machine-illustrated in Fig. 1 with the face platerer'noved.

Fig. 5 is an enlarged fragmentary detail view illustrat ing the feeding mechanism per se in elevation.

Fig. 6is an enlarged fragmentary detail view in top plan of the drivin connection-for the feed lift shaft.

Fig. 7 is a fragmentary detail sectional view taken sub stantially entire line 7 7 of Fig. 5.

The present invention is herein disclosed as embodied in a sewing machine as disclosed and claimed in my prior application Serial No. 609,836 to which application reference may be hadfol' a more complete description of the machine. As disclosedin the drawings, the illustrated machine ccm nsesatrame having a bed 1 from'the one end of which rises astandard Zcarrying' a bracket arm 3 that-terminates in a head 4.= The open end of the head dis closed by aface plate'5 and the open'top ofthe bracket ar'm sis closed bya top cover plate 6. Journaled longitudinally of the bed 1 is a driven rotarymain shaft 7 A needle bar 8 is mounted vertically for endwise reciprocatory movement in the head 4. To impart reciprocation to the needle bar 8, there is a rock lever indicated. generally as 9, arranged longitudinally of the bracket arm 3 and having a hub 10 secured to a pivot shaft 11 that is journaled transversely of the bracket arm 3, A lever arm 12 extends from the hub 11 toward the head 3*"and the free end thereof is connected to the needle bar 8. A second lever arm 15 extends from the hub 11 toward the standard 2 and the free end thereof is con-, nected by a pitman 16 to a crank 17 on the main shaft 7.

The bracket arm 3 is provided with two sets of aligned bearings comprising an upper set including a bushing 18provided in a boss 19 at the standard end of the bracket arm and two bushings 20 provided in bosses 21 atthe head endof the bracket arm, and a lower setof bearings including a bushing 22 secured in a boss 23 at the standardend of the bracket arm and two bushings 24 provided in bosses 25 at the head end of the bracket arm. An upper attachment drive shaft 26 is journaled in the bushings 18 and 20 and a lower attachment drive shaft 27 'is journaled in the bushings 22' and 24. With reference to my prior application Serial No. 609,836, these attachment drive shafts are designed to be used either singly or in combination to actuate any selected one of a number of different attachment mechanisms. In accordancewith the present invention, both of these attachment drive shafts are used for a top fourrnotion feeding mechanism ashereinafter disclosed, the shaft 26 comprising the feed lift shaft and the shaft 27 comprising the feed advance shaft.

As is fully disclosed in my prior application Serial No. 609,836, and as can be seen in Fig. 2, the bracket arm 3 is angled relatively to the bed to position the head 4 forwardly relatively to the standard, thus increasing the visibility at the pointof stitch formation and also facilitating reaching behind the head 4 in the manipulation of the work. Also,- the ends of the lever arms 12 and 15 of the rock lever 9 are located on a line normal to the pivot axis of therock lever 9 to avoid distortion at the pivotshaft 11. Further, the

attachment drive shafts

26 and 27 are to be arranged parallel to the mainshaft 7 to avoid the necessity of complicated drive connections, and at the same time, must be arranged longitudinally of the bracket arm 3 without interfering with the oscillation of the rock lever 9; Thus, in the construction disclosed and claimed in my prior application Serial No; 609,836, the

attachment drive shafts

26 and 27 are disposed in vertically spaced relation parallel to the main shaft 7 with theupper shaft 26 passingover thehub Not the rock lever 9 and the lower shaft 26 passing under the hub 10, and the lever arms 12 and 15 are spaced laterally on the hub 10 with the lever arm 12 disposed wholly in front of the

shafts

26 and 27 and the lever arm 15 disposed wholly to the rear of the

shafts

26 and 27. In this construction, the

shafts

26 and 27 are therefore angled through the bracket arm 3 so that at the head end of the machine they are disposed to the rear of the bracket arm and at the standard end they are disposed at the front of the bracket arm.

In the illustrated machine there is a presser mechanism comprising a presser foot 28 mounted upon the lower end of a presser bar 29 that is mounted for cndwise sliding in the head 4. The presser lifter mechanism. coinprisesa collar 30 fast on the presser bar 29 and connected by a link 31 to one armrof a bell crank lever 32, the-other arm of which is connected by a link 33 to a crank arm 34 secured on a presser lifter shaft 35 journaled transversely in the standard 2 and having an operator-aotuatedlever arm 3613i: the rear of the standard The resser foot acts to hold the work down against a throat plate 37 and in cooperation with the feed dog 38 of a lower four-motion feeding mechanism details of which are not shown.

In accordance with the present invention there is pro-- vided a top four-motion feeding mechanism comprising a vertically arranged feed bar 39 carrying a feeding foot 40 at its lower end. The feed bar 39 is guided for movement 1n a vertical plane parallel to the line of stitch formation by a strap 41 secured to the end of the head 4 by screws 42 and having a groove 43 in which the feed bar 39 moves, the feed bar thus being held loosely between the end of the head 4 and the bottom of the groove 43 in the strap 41.

Adjustable feed advance movements are imparted to the feed bar 39 by the lower attachment drive shaft 27 which s used as the feed advance shaft through a vertically arranged crank arm 44 secured on the head end of the shaft 27 and connected at its free end by a link 45 to an intermediate point on the feed bar 39. Thus, oscillation of the shaft 27 will impart feed advance movements to the feed bar 39. Oscillation is imparted to the shaft 27 by a crank arm 46 mounted on the standard end thereof and connected by a pitman 47 arranged vertically in the standard 2 to an adjustable eccentric 48 forming one of the elements of a double adjustable eccentric 49 mounted on the main shaft 7.

Rising and falling movements are imparted to the feed bar 39 by the upper attachment drive shaft 26 which is used as the feed lift shaft through a horizontally arranged crank arm 50 mounted upon the head end of the shaft 26 and connected at its free end to the upper end of the feed bar 39. Thus. oscillation of the shaft 26 imparts movement to the feed bar 39 toward and away from the throat plate 37. Oscillation is imparted to the shaft 26 by a pitman 51 arranged vertically in the standard 2 :and connected at its lower end to an eccentric 52 which forms the other element of the double adiustable eccentric 49. At its upper end. the pitman 51 is pivotally connected to an intermediate point on a lever 53 (Fig. 3) by a pivot 54 secured to the lever 53 by a set screw 55 and having the ends thereof upon the opposite sides of the lever 53 jou-rnaled freely in the bifurcated end of the pitman 51. The lever 53 has a hub 56 (Fig. 2) at one end which is loosely journaled on the shaft 26 and at its free end is formed as a fish-tail 57 having a V-shaped slot defined bv a 'pair of

edges

58 and 59 that diverge from a throat 60. A crank arm 61 is provided with a bifurcated hub having apertured tines 62 that are mounted on the shaft 26 on op osite sides of the hub 56 of the lever 53, and are secured thereon by set screws 63. At its free end. the crank arm 61 has a transverse pivot pin 64 secured therein by a set screw 65. u on which pin 64 is loosely journaled one end of a connecting link 66. the pin 64 extending throu h tines 67 in the bifurcated end of the link 66. The other end of the link 66 is bifurcated to provide tines 68 which are arranged upon the op osite side of the fish-tail 57 in the end of the lever 53. A pin 69 extends between the tines 68. A wire spring 70 is wrap ed around the hubs 71 on the tines 67 for the pivot pin 64 and the o posite arms thereof overlie the crank arm 61 and the links 66 to bias them to collapse about the pivot pin 64. A coil spring 72 is dis osed on the shaft 26 and has one end thereof anchored in a bore 73 in a collar 74 secured to the shaft 26 by set screws 75. The other end of the spring 72 overlies the lever 53 to bias it in a clockwise direction as seen in Fig. 5.

' To lift the feeding foot 40 from the work. such as for introducin work. there is a stud screw 76 threadedinto the collar 30 on the presser bar 29 and extending into an opening 77 in the feed bar 39. The opening 77 is elongated vertically and horizontally to provide in effect a lost motion connection for accommodating feeding movements of the feed bar 39 independently of the stud screw 76. When the presser foot 28 is lifted, the screw 76 moves upwardly with the presser bar 29 and when it con- 4 I tacts the top of the opening 77, continued raising of th presser bar 29 will also raise the feed bar 39.

In the operation of theffeed lifting and lowering mechanism, as the pitman 51 israised by the eccentric 52, the lever 53 is pivoted upwardly or in a counterclockwise direction as seen in Fig. 5 about the axis of the shaft 26. This movement is transmitted directly to the feed lift shaft 26 through the spring 72 to turn the shaft and through the crank arm 50 to lower the feed bar 39 and the feeding foot 40 toward the work. As soon as the feeding foot 40 contacts the work, indicated at W in Fig. 5, and is thus held against further downward movement which also holds the shaft 26 against further turning, continued rising of the pitman 51 will cause the lever 53 to pivot about the shaft 26 on-which it is journaled, the relative motion of the lever 53 relative to the shaft 26 being taken up in the yielding of the spring 72 so that the spring 72 resiliently biases the feeding foot 40 into operative engagement with the work. The throw of the eccentric 52 is adjusted to provide for feeding of the minimum thickness of work to be encountered. Thus, as the thickness of the work varies, as for example by a cross seam such as indicated as S in Fig. 5, the amount that the shaft 26 is turned will be varied. More particularly, with reference to Fig. 5, there is illustrated a full line and dotted line position of the parts. In the full line position a minimum thickness of the work W, represented by a single thickness, is illustrated beneath the feeding foot 40, and, in the dotted line position, a maximum thickness of work represented by the cross seam 5 is illustrated beneath the feeding foot 40. Thepitman 51 is illustrated in its position of maximum rise. In both cases, the amount of turning imparted to the lever 53 is the same, and in both cases, the feeding foot 40 is biased against the work by the same force, which is that of the spring 72. However, the vertical position of the feeding foot is varied in accordance with the variation in the thickness of the work, and the variation in the posititon of the parts is taken up by the yielding of the spring 72.

While the pitman 51 is lifting the lever 53 and, through the spring 72, turning the shaft 26, the crank arm 61, link 66 and lever 53 will remain in the relative position as illustrated in full lines in Fig. 5, i.e., with the pin 69 of the link 66 seated in the throat 60 of the fish-tail at the free end of the lever 53. When further turning of the shaft 26 is prevented by engagement of the feeding foot 40 with the work, the crank arm 61, which is secured to the shaft 26, is also held against further turning and continued rising of the pitman 51 will pivot the lever 53 relatively to the crank arm 61, thus moving the pin 69 out of the throat 60. As the pitman 51 is lowered by the eccentric 52, the lever 53 will be turned in a clockwise direction as seen in Fig. 5. The spring 72 will be relaxed while still holding the feeding foot 40 in engagement with the work until the pin 69 is seated in the throat 60. In this position the spring 72 is captive and there is then a direct connection from the pitman 51, through the lever 53, pin 69, link 66 and crank arm 61 to the shaft 26 so that continued lowering of the pitman 51 will pivot the shaft 26 to lift the. feeding foot 40 from the work.

The connection at the pin 69 and fish-tail 57 comprises in effect a lost motion connection which is designed to accommodate the relative motion between the lever 53 and crank arm 61. If the pin 69 were separated from the lever 53 as it moves out of the throat 60, there would be a slap when they were brought back into contact, which would generate considerable noise at high speeds. To hold the pin 69 continually in engagement with the lever 53, there is provided the spring 70 which tends to pivot the link 66 relatively to the crank arm 61 in a direction to hold the pin 69 against the edge 58 of the fish-tail. The edge 58 formed to extend radially outwardly of the throat 60 relatively to the pivot axis of the link 66, which is the axis of the pivot pin 64. As the pin 69 is moved out of the throat 60 by the turning of the lever 53 toward the crankaarm 61,1 theciink-Gfi is pivoted by the spring 70 sothat the pin*69nwill-slide along the edge 58. As seenin Fig..5,.the amount that the pin 69 moves out of .the throat 60 depends upon the thickness of the work. In the-full line position-which represents a minimum thickness, the pin 6moves1out of the throat 60 an imperceptible amountsin'ce the pitman SI has virtually completed its rise by the time the feeding foot 40 has cont-actedthe work and thusstopped the turning of the shaft -26 and crank arm 61; In the dotted line position, which representsva maximum thickness, the pin 69 moves out ofthe' throat 60 and slides along the edge 58 substantially to the end. The spring 72 is stronger than the spring 70 so that as the lever 53 is pulled down by the pitman- 51, the link 66 will be pivoted against the action of the spring 70 by the 'camnaction between the pin 69 and edge 58 as'the pin :68 slides along the edge 58and returns to the throat 60; -When in the throat 60, the pin 69 constitutes a direct tension connection between the lever 53and link 66,

The timing of the advance movements and the rising and falling movements of thefeedinglfoot40 are such that the advance movementlof'the'feeding foot 40 in a feeding stroke is madelwith the feeding foot 40 lowered in engagement with the work and thereturn movement occurs when the feeding foot '40 is out of engagement with the Work. The movements of the feeding foot 40 are synchronized with the action of the lower feeding mechanism including the fecddog 38.

Numerous alterations of the. structure herein disclosed will suggest themselves'to those skilled in the art.. However, it is to be understood that the present disclosure relates to a preferred embodiment "of my invention which is for purposes of illustration 1 only and not'to be con strued as a limitation of the invention. All such modification which do not depart from the spirit of the invention are intended to be included within the: scope of the appended claims.

Having thus set forth the nature of the invention, what I claim herein is: r

1. In a sewing machine h ving a frame including a work support and a bracket arm overhanging said work support, a feed lift shaft journaled in said frame, a feed bar carried by said frame for feeding movements, means operatively connecting said shafttosaid feed bar for imparting feed rising and falling" movements to said feed bar upon rocking of said shaft, and means for imparting rocking movement to said shaft comprising a lever pivotally mounted on said shaft, a crank arm secured to said shaft, a torsion spring surrounding said shaft and acting between said lever and a collar adjustably secured on said shaft, and means disposed between said lever and crank arm for permitting motion of said lever relatively to said crank arm in that direction which urges said shaft to turn in said one direction andfor limiting motion of said lever relatively to said crank arm in the opposite direction, and means for imparting oscillation to said lever.

2. In a sewing machine having a framc including a work support and a bracketarm overhanging said work support, a feed lift shaft journaled in said bracket arm, a crank arm extending laterally from said shaft, a feed bar pivotally-conncctedtoisaid crank arm, .and means for imparting rocking movement to said shaft to impart rising and falling movements to said feed bar comprising a pair of cooperating elements including a lever pivotally mounted on said shaft and a second crank arm secured to said shaft, s ring means operatiyely connecting said lever to said shaft for biasing said shaft to turn in one direction, a link disposed between saidlever and crank arm and being pivotally carried by onevof said elements and having a lost-motion connection with theother of said elements, said link through the lost-motion connection permitting motion of said lever relatively to said second crank arm in that direction which urges said shaft d to turn insaid one direction and for limiting motion of said lever relatively to said second crank arm in the opposite direction, and means for imparting oscillation to said lever.

3. In a sewing machine having a frame includinga work support and a bracket arm overhanging said work support, a feed lift shaft journaled in said bracket arm, a crank arm extending laterally from said shaft, a feed bar pivotally connected to said crank arm, and means for imparting rocking movement to said shaft to impart rising and falling movement to said feed bar comprising a pairv of cooperating elements including a lever pivotally mounted on said shaft and a second crank arm secured to said shaft, spring means operatively connecting said lever to said shaft for biasing said shaft to turn in one direction, a link disposed between said lever and crank arm and. being pivotally secured to one of said elements and having a lateral extension engaging the other of said elements on the side to limit pivotal motion of said lever relatively tosaid crank arm under the action of said spring means, said element at the point of engagement with said lateral extension having a throat and an edge extending from said throat along a line diverging radially relatively to the pivot axis of said link, a spring pivotally biasingsaid link into engagement with said edge, and means for imparting oscillation to said lever.

4. Ina sewing machine having a frame including a bed, a standard rising from one end of said bed, and abracket arm carried by said standard and overhanging, said bed, a rotary main shaftljournaled in said bed, a feed advance shaft and a feed lifting shaft journaled, in said bracket arm, a feed bar carried by said bracket arm for feed advance and return and feed rising and falling movements in a plane defining a normal line of feed, means operatively connecting said feed advance shaft to said feed bar for imparting feed advance and return movements thereto upon'actuation of said shaft, means operatively connecting said feed lifting shaft to said feed bar for imparting feed rising and falling movements to said feed bar upon actuation of said shaft, a pair of eccentrics on said main shaft, a pair of pitmans extending through said standard and operatively connected individually to said eccentrics, means operatively connecting a first one of said pitmans to said feed advance shaft for actuating said feed advance shaft upon rotation of said main shaft, and means operatively connecting the second one of said pitmans to said feed lifting shaft foractuating said feed lifting shaft upon rotation of said main shaft, said last mentioned means including a resilient connecting element that is flexed upon continued movement of said pitman after the feed bar is in engagement with the work for uniformly biasing the feed bar toward the work upon variations in the thickness of the work. 7

5. In a sewing machine having a frame, a main shaft journaled in said frame, a feed lifting shaft journaled in said frame, a feed bar carried by said frame for movement in aplane, operative connections between said feed bar and said main shaft for imparting feed advance and return movements to said feed bar upon rotation of said main shaft, means operatively connecting said feed lift ing shaft and said feed bar for imparting feed rising and falling movements to said feed bar upon actuation of said feed lifting shaft, and means for actuating said feed lifting shaft comprising an actuating element on said main shaft, a pitman operatively connected to said actuating element for imparting endwise movement to said pitman upon rotation of said main shaft, a lever pivotally mounted on said feed lifting shaft and pivotally connected to said pitman, resilient means connecting said lever to said feed lifting shaft for biasing said shaft to turn in a direc tion to move the feed bar toward the work, and means forholding said resilient means captive during that portion of the feeding cycle when said feed bar is outside the range determined by the maximum anticipated thickness of the work and during the remaining portion of 7 the cycle when said feed bar is out of engagement with the work.

6. In a sewing machine having a frame, a main shaft journaled in said frame, a feed lifting shaft journaled in said frame, a feed bar carried by said frame for movement in a plane, operative connections between said feed bar and said main shaft for imparting feed advance and return movements to said feed bar upon rotation of said main shaft, means operatively connecting said feed lifting shaft to said feed bar for imparting feed rising and falling movements to said feed bar upon actuation of said feed lifting shaft, and means for actuating said feed lifting shaft comprising an actuating element on said main shaft, a pitman operatively connected to said actuating element for imparting endwise movement to said pitman upon rotation of said main shaft, a lever pivotally mounted on said feed lifting shaft and pivotally connected to said pitman, resilient means connecting said lever to said feed lifting shaft for biasing said shaft to turn in a direction to move said feed bar toward the work, means operatively connecting said lever to said feed lifting shaft for turning said shaft in the opposite direction, said last mentioned means including a lost-motion connection to provide for relative motion between the same and the lever when said feed bar is in contact with the work and is thereby held against further movement.

7. In a sewing machine having a frame, a main shaft journaled in said frame, a feed lifting shaft journaled in said frame, a feed bar carried by said frame for movement in a plane, operative connections between said feed bar and said main shaft for imparting feed advance and return movements to said feed bar upon rotation of said main shaft, means operatively connecting said feed lifting shaft and said feed bar for imparting feed rising and falling movements to said feed bar upon actuation of said feed lifting shaft, and means for actauting said feed lifting shaft comprising an actuating element on said main shaft, a pitman operatively connected to said actuating element for imparting endwise movement to said pitman upon rotation of said main shaft, a lever pivotally mounted on said feed lifting shaft and pivotally connected to said pitman, resilient means connecting said lever to said feed lifting shaft for biasing said shaft to turn in a direction to move said feed bar toward the work, a crank arm secured to said feed lifting shaft, means carried by the crank arm and cooperating with the free end of said lever for providing a positive connection between said crank arm and said lever for turning said crank arm and thereby turning said feed lifting shaft in a direction to move said feed bar away from the work and for providing a lost-motion connection in the opposite direction for turning of said lever relatively to said crank arm and feed lifting shaft against the action of said resilient means.

8. In a sewing machine having a frame, a main shaft journaled in said frame, a feed lifting shaft journaled in said frame, a feed bar carried by said frame for movement in a plane, operative connections between said feed bar and said main shaft for imparting feed advance and return movements to said feed bar upon rotation of said main shaft, means operatively connecting said feed lifting shaft to said feed bar for imparting feed rising and falling movements to said feed bar upon actuation of said feed lifting shaft, and means for actuating said feed lifting shaft comprising an actuating element on said main shaft, a pitman operatively connected to said actuating element for imparting endwise movement to said pitman upon rotation of said main shaft, a lever pivotally mounted on said feed lifting shaft and pivotally connected to said pitman, resilient means connecting said lever to said feed lifting shaft for biasing said shaft to turn in a direction to move said feed bar toward the work, a crank arm secured to said feed lifting shaft, a link pivotally mounted on said crank arm, and a pin carried by said link and underlying the free end of said lever for providing a positive connection=between said crank arm and said lever for turning said crank. arm and thereby turning said feed lifting shaft in a direction to move said feed bar away from'the-wo'rk and for providing a lost-motion connection'in the opposite direction for turning of said lever relatively tosaid crank arm and feed lifting shaft against the action of said resilient means.

9. In a sewing machine having a frame, a main shaft journaled in said frame, a feed lifting shaft journaled in said frame, a feed bar carried by said frame for movement in a plane, operative connections between said feed bar and said main shaft for imparting feed advance and return movements to said feed bar upon rotation of said main shaft, means operatively connecting said feed lifting shaft and said feed bar for imparting feed rising and falling movements to said feed bar upon actuation of said feed lifting shaft, and means for actuating said feed lifting shaft comprising an actuating element on said main shaft, a pitman operatively connected to said actuating element for imparting endwise movement to said pitman upon rotation of said main shaft, a lever pivotally mounted on said feed lifting shaft and pivotally connected to said pitman, resilient means connecting said lever to said feed lifting shaft for biasing said shaft to turn in a direction to move said feed bar toward the work, a crank arm secured to said feed lifting shaft, a link pivotally mounted on said crank arm, the free end of said'lever being formed with a throat and an edge extending from said throat on a line diverging radially relatively to the pivot axis of said link, a pin carried by said link and underlying the free end of said lever and adapted to be seated in said throat for providing a positive connection between said crank arm when said lever is turned in a direction to move said feed bar away from the work and adapted to move freely out of said throat for providing a resilient connection through said resilient means to provide for turning of said lever relative to said crank arm and feed lifting shaft against the action of said resilient means when said lever is turned in the direction to move said feed bar toward said work, and resilient means for biasing said link about its pivot axis into sliding contact with said edge of the lever as it is moved out of said throat.

10. In a sewing machine having a frame including a work support and a bracket arm overhanging said work support, a feed lift shaft journaled in said frame, a feed bar carried by said bracket arm for feeding movements, means operatively connecting said feed lift shaft to said feed bar for imparting feed rising and falling movements to said feed bar upon rocking of said shaft, and means for imparting rocking movement to said shaft comprising a lever pivotally mounted on said shaft, a crank arm secured to said shaft, spring means operatively connecting said lever to said shaft for biasing said shaft to turn in one direction, means disposed between said lever and crank arm for permitting motion of said lever relatively to said crank arm in that direction which urges said shaft to turn in said one direction and for limiting motion of said lever relatively to said crank arm in the opposite direction, and means for imparting oscillation to said lever.

References Cited in the file of this patent UNITED STATES PATENTS Kelly Ian. 28, 1958