US2854935A

US2854935A - Automatic shifting mechanism for sewing machines adapted for embroidery work

Info

Publication number: US2854935A
Application number: US545482A
Authority: US
Inventors: Benink Christian Josef Marines; Bungert Heinrich
Original assignee: GM Pfaff AG
Current assignee: GM Pfaff AG
Priority date: 1953-11-19
Filing date: 1955-11-07
Publication date: 1958-10-07
Anticipated expiration: 1975-10-07
Also published as: BE542467A; GB762328A; GB792328A; FR1137737A; CH336252A

Description

OC- 7, 1958 c. J. M. BENINK ETAL 2,854,935

AUTOMATIC SHIRIING MROHANISM FOR SEWING Y MACHINES AOAPIRO FOR EMBROIDERY WORK Filed Nov. 7, 1955 4 Sheets-$heet l Oct. 7, 1958 c. J. M. BENINK ETAL 2,854,935

AUTOMATIC sHIETIm MEcHANIsM EOE SEWING MACHINES ADAPTEO EOE EMBROIDERY WORK 4 Sheets-Sheet 2 Filed NOV. 7, 1955 Oct. 7, 1958 c. J. M. BENINK ETAL v 2,854,935

AUTOMATIC SHIF'TING MECHANISM FOR SEWING MACHINES ADARTED RoR EMBROIDERY woRR Filed NOV. 7, 1955 4 Sheets-Sheet 3 ff/vr Oct. 7, 1958 Filed NOV. 7, 1955 C. AUTOMATIC SHIFTING MECHANISM FOR SEWING J M. BENINK ETAL 2,854,935

MACHINES ADAPTED FOR EMBROIDERY WORK 4 Sheets-Sheet 4 745' f 90 f2 146129 sa 752 f5@ Agi/vr United States Patent O AUTOMATIC SHIFTING MECHANISM FOR SEW- ING MACHINES ADAPTED FOR EMBROIDERY WORK Christian Josef Marines Beninlr and Heinrich Bungert, Kaiserslautern, Germany, assignors to G. M. Pfad A.G., Kaiserslautern, Germany Application November 7, 1955, Serial No. 545,482 Claims priority, application Germany November 9, 1954 11 Claims. (tCl. 112-158) This invention relates to a shifting and guiding mechanism for zig zag sewing machines having a control'device which permits the adjustment of the stitch location and of the stitch width separately as well as simultaneously for the purpose of producing a plurality of diierent stitch designs from a design disk.

ln a known arrangement this is achieved in that the guiding impulses derived from the design dial are transferred to swinging adjusting links. From these they are applied by means of guide bars to oscillating shafts which are in operative engagement with the bearing stud of the oscillating lever of the needle bar oscillator. The operation of the guiding device is effected from the crank shaft by way ol? an adjustable cam, the deflections or throws of which are applied to a stepping device which, in turn, drives the design dial.

It is possible with devices of that type to derive a large number of design variations from a design disk; but the proper operation of the numerous adjusting elements mounted externally of the machine arm requires the use of both hands and is cumbersome and tir're consuming. Furthermore, the known arrangement cannot be readily installed in a simple Zig zag sewing machine of conventional construction.

In another known arrangement the design dial is driven by the motor by way of a step cone and a worm drive mounted in the standard of the machine. The guiding impulses derived from the dial disk are transferred to a suspended arm rotatably mounted in the machine arm by means of an oscillating lever and an adjustable transmission bar, and from there the impulses may be applied to the adjustment levers for the stitch location and the width by means of a manually operated lever connection which is likewise provided externally of the machine arm.

Also here the adjustment of the designs is relatively cumbersome, especially as far as the change over to different design lengths is concerned. For that purpose it is necessary for each change to change over the belt on the step cone pulley.

Furthermore, step switching mechanisms have been proposed in connection with fancy stitch sewing machines for producing star patterns where the length of the steps is made adjustable by following certain procedure.

The problem underlying the invention is to eliminate the shortcomings of the known arrangements and it is one object of the invention to provide a shifting and guiding mechanism which makes it possible with simple structural means to provide for continuous or stepless adjustment even during the running of the machine. The invention solves this problem by means of engageable and disengageable connections between the transfer lever for the guiding impulses and the adjusting levers for the stitch location and the stitch width and furthermore by means of a selector switch for engaging and disengaging the connections and by a means for the continuously ad- 2,854,935 Patented Oct. 7, 1958 2 justable variation of the advancing length of the drive for the control mechanism.

In the preferred embodiment it is possible to provide supports for yokes upon the transfer lever which coopcrate with spring loaded coupling or shifts bars connected to the adjusting levers of the machine. It is furthermore appropriate to movably connect the shift bars with the adjusting levers for the stitch location and the stitch width by means of eccentric bolts. Furthermore, it is suitable to make the adjusting pressure of the springs for the coupling bars which are mounted on a carrier rack variable by means of set screws.

In accordance with a further object of the invention the engaging and disengaging of the shifting bars can be effected by a cam shaft operated by the selector switch, which carries additional cams besides the cams associated with the shifting bars, in particular one cam which, for a specific position of the selector switch, keeps the transmission system for the control impulses out of engagement with the control mechanism, and one cam which, in response to predetermined positions of the selector switch, operates the stitch location control. In this connection the particular shifting positions of the selector switch can be secured by a toothed rack.

A still further object of the invention provides for a possibility of inlluencing the stitch location adjustment by means of the selector switch by way of a double armed lever mounted rotatably under control of a spring on the outside of the machine arm, one arm of which lever extends into the interior of the machine arm and rests with its angular end against the cam of the cam shaft while the other arm extends downwardly on the outside of the machine arm and is provided with teeth forming a rack which, when the stitch location control is in operative position, are in engagement with the point of the adjusting lever for the stitch location.

A further object of the invention is to provide a cone shaped cam on the drive shaft which is operatively connected to a step by step advancing mechanism for operating the control mechanism by way of an adjustably mounted double armed lever and a push rod. The pivot of the double armed lever may be mounted on a slide member which is slidably mounted on a supporting plate secured to the machine arm and adjustable by means of a switch provided in the cover of the machine.

Further features and objects of the invention and details of the advantages provided thereby will become apparent from the following description of one embodiment of the switching mechanism illustrated in the accompanying drawings in connection with a zig zag sewing machine in which Fig. l is a perspective front view of a sewing machine equipped with the mechanism in accordance with the invention;

Fig. 2 is a further perspective view looking down on the machine with the cover removed;

Fig. 3 is a perspective view of a portion of the machine with the cover removed and of the raised mechanism from the bottom;

Fig. 4 is a partial perspective and exploded view of the machine with the cover removed and the mechanism raised with the dismounted coupling bars without the springs at the top;

Fig. 5 is a partial view of the machine arm from the front with the cover removed, with the shifting bars and springs, the transfer lever, the earn shaft without bearing means and selector switch, the stitch adjuster without adjusting knob -or indicating dial;

Fig. 6 is the transfer lever with the carriers or sup` Fig. 7 is an exploded view of the transfer elements for the design length adjustment and the journalling of the slide upon the support;

Fig. 8 is the cam shaft with the bearing member and the selector switch;

Fig. 9 is a side view, partly in section, showing the switching device installed in a zig zag type sewing machine for cooperation with the conventional type of needle bar oscillator mechanism;

Fig. l is an exploded view of the stitch location lever and of the cam fork rod and their interengaging elements, and

Fig. 1l is a plan view of a unidirectionally operating cam nest advancing device in the form of a clutch.

The shifting or switching mechanism is mounted on the arm 1 of the machine beneath the cover 2 which is provided with a ilap 3 and bores for the shifting shafts of the mechanism.

A supporting plate 4 is provided with bores 5 for screws 6 by means of which it is secured in the threaded bores 7 of the machine arm 1. A cam disk assembly 8 rotatably mounted on the supporting plate 4 is moved by a continuously (stepless) adjustable advancing device 9 which is connected for operation by way of variable cam drive means including a pusher bar 10 and adouble armed lever 11 to a conical cam 13 secured to the drive shaft 12 in the machine arm. The device 9 is preferably of a conventional ratchet and pawl, or wedge, or one way clutch type which, when rotate-d in one direction rotates the shaft of the cam assembly, while on the return movement it slides over its engagement with the cam assembly so that the cam assembly is only moved in one direction. Fig. l1 shows one such device by way of example. The double armed lever 11 is spring biased by means of a tension spring 14 which is hooked at one end to said lever and at the other end to the supporting plate 4 by means of a screw 15, which holds it with its free arm 17 which is provided with a roller 16 in uninterrupted operative engagement with the cam 13. The lever 11 is rotatably mounted by means of its hub 18 of tubular shape (Fig. 7) upon a shaft 19 and is retained by a fastening ring 20. The shaft 19 is mounted upon a slide 21 which is movable parallel to the drive shaft 12 and which is held and guided on the supporting plate 4 by means of

collar screws

22, 23 which extend through

longitudinal slots

24, 25. The movement of the slide 21 is limited in the direction toward the head of the machine by means of a guide member 28 mounted on the supporting plate 4 by means of screws 27 in a recess l26 of the slide 21.

A pin 29 projects through longitudinal slot 25 in the slide 21 and serves as an abutment for a lug 30 on the pusher bar 10 in the inoperative position of the slide 21. A pin 33 secured to an angular lever 32 engages a recess 31 in the slide 21. The angular lever 32 is rotatable around a pivot shaft 34 and is provided with a slot 35 which is engaged by a pin 36 on a collar 39 mounted upon a shifting shaft 37 to which it is secured by means of a set screw 38. The shifting shaft 37 projects through the cover 2 and carries a manipulating knob 40 at its upper free end which has curved recesses 41 for seating a spring biased ball (not shown) which is embedded `in the top surface of cover 2 under knob 40. The supporting plate 4 is provided with a correspondingly large longitudinal aperture 42 so that the pin 33 can readily reach through for operating the slide 21.

An angular lever 44 pivoted on a bolt 43 (Figs. 2, 4) carries at its vertex a rotatably mounted shifting start 46 provided with a locking means 45 and having feeler ngers 47 for selecting a cam disk from the nest of cam disks. A lever 49 is linked to the free end of the angular lever 44 by means of a collar screw 48, which lever is provided with slots 50 longitudinally thereof for the adjustable connection with a lever 51 by means of screws 52. Lever 51 is pivotally connected at its other end by means of a collar screw 53 to a transfer lever 55 pivotally supported on a threaded bolt 54.

Thus the

lever mechanism

44, 49, 51, 55 for receiving and transferring the control movements, which is pivoted around

bolts

43 and 54 and carries the shifting star 46, constitutes a coupling system or impulse transfer means which is held in operative engagement with the cam disk nest 8 by means of a spring 56. The spring 56 is hooked at one end to a lug 57 on the transfer lever 55 and secured at its other end to the supporting plate 4 by means of a screw 58.

Three bearing

bushings

59, 60, 61 are provided, on the transfer lever 55 which rotatably receive

studs

62, 63, 64 of

supports

65, 66, 67 and which are secured to said lever by

screws

68, 69, 70. The supports 65, 66, 67 are provided at their ends with

slots

71, 72, 73 and

yokes

74, 75, 76. Coupling bars 77, 78, 79 which are guided in the

slots

71, 72, 73 are provided at one end with recesses 80, 81, 82 for seating in the

yokes

74, 75, 76. At the other end the coupling bars 77, 78, 79 are movably connected to the shifting levers of the machine by means of

eccentric collar bolts

83, 84, 85. The collar bolt 83 carrying the coupling bar 77 is secured in a bore 86 in an extension lever 87 by means of a set screw 88. The extension lever 87 is secured by means of a screw 89 to the stitch location adjusting lever 90 which at its lower end rotatably receives the shaft 92 of the stitch adjuster or locater in a bearing 91.

The

collar bolts

84, 85 of the coupling bars 78, 79 are secured in

bores

93, 94 on both sides of an angular lever 95 by means of

screws

96, 97. The angular lever 95 (Fig. 5) is pivotally connected in a known manner by way of a pull bar 98 to a one armed lever 100 which is secured by means of a screw 99 to the shaft 92 of the stitch adjuster.`

A bearing member 1'01 (Figs. 3 and 8) is mounted upon the supporting plate 4 by means of screws 102 and accommodates between its upwardly extending cheeks 103, 104 a cam shaft 105, which is disposed transversely of and beneath the coupling bars 77, 78, 79. A toothed gear 106 is disposed upon the end of the cam shaft 105 which extends through the cheek 104 which meshes with another toothed gear 107 mounted by means of a bolt 108 upon cheek 104. The hub 109 of gear 107 supports a selector switch 110 which is provided on its front face with markings 111 and on the rear surface with corresponding indentations or cavities 112 for seating a spring biased ball 112a mounted in the hub 113 of the gear 106.

Cams

114, 115, 116 associated with

coupling bars

77, 78, 79 are mounted von the cam shaft 105 which, in corresponding positions of the selector switch 110, disengage the coupling bars 77, 78, 79 from the

yokes

74, 75, 76 of the

supports

65, 66, 67. There is furthermore provided upon the cam shaft a cam 117 which in the position of disengagement of the selector switch engages a lug 118 of the transfer lever 55 and removes the transfer system for the control or shifting movements from engagement with the nest of cam disks 8, and also a cam 119 which in predetermined positions of the selector switch 110 operates a double armed lever 120 (Fig. 5) and thus shifts the stitch location adjustment. One arm 121 of the double armed lever 120 is provided with recesses 122 while the other arm 123 bulges out and extends at an angle at the end in the direction of the balance wheel. On the outside of the arm 1 lever 120 is rotatably mounted by means of a collar screw 124 and extends with its curved arm 123 through an aperture 125 to the inside of housing arm 1 to cam 119 on the cam shaft 105 where it is held in continuous engagement by a tension spring 126. Spring 126 is hooked onto arm 123 at one end and at the other end onto a pin 127 on the machine housing arm. The other arm 121 of the double armed lever which extends downwardly is adapted to receive in one of its recesses 122 the edge 128 of the stitch location adjusting lever 129 which, in a known manner, is rotatably and resiliently disposed in the bearing 91 of the stitch location adjusting lever 90 as shown in Fig. 5.

The coupling bars 77, 78, 79 are biased by

springs

130, 131, 132 which are secured by means of screws to

mountings

133, 134, 135. These

mountings

133, 134, 135 are movably supported upon a yoke 137 secured to the supporting plate 4 by means of screws 136 and are provided with lugs through which extend adjustment or set screws 138 which are supported on a plate 140 secured to the supporting plate 4 by means of screws 139. The pressure of the

springs

130, 131, 132 against the ycoupling bars 77, '78, 79 can be adjusted by means of set screws 138.

The manner in lwhich the mechanism operates is now described. However, before discussing the shifting mechanism proper, a brief explanation is given of a conventional zig zag stepping mechanism and of the manner in which the shifting mechanism in accordance with the invention cooperates therewith.

The stitch location adjusting lever 90 and the angular lever 95 are pivotally supported in the machine arm 1 upon a stud 141. At the end of shaft 92 of the stitch locator which projects through the aperture 125 an operating knob 143 is secured by means of screw 142 (Fig. 3), which serves for manually setting the width of the stitch.

Between the knob 143 and arm 1 an indicator dial 144 is provided for indicating the adjusted stitch width. This dial moves together with knob 143 and the stitch location lever 129 as they are turned to change the position of shaft 92, but retains its adjusted position relative to the machine. Furthermore, pointer 145 is formed on the dial 144 which cooperates with the markings 146 provided upon machine arm 1 to indicate the stitch location.

At the other end of the shaft 92 of the stitch adjusting means the stitch adjuster guide member 147 (Fig. 9) is mounted in which is guided the sliding member 149 which is rotatably mounted upon the cam fork rod 148. The fork 150 of the cam fork rod 148 receives the stitch locating cam 151 which is driven by way of the bevel gears 152 and 153 from the drive shaft 12. The cam 151 and the bevel gear wheel 153 are rotatably disposed on a stud (not shown) which is secured in the machine arm 1 at the rear of the machine housing. The cam fork rod 148 is connected by means of a movable joint 154 to the needle bar oscillator 156 which is pivotally supported at bearing stud 155. The needle bar oscillator 156 receives the needle bar 157 for reciprocating movement, which in turn is in operative engagement with the bell crank lever 159 secured to the housing arm 12. Cam 151 effects one half revolution in response to one up and down movement of needle bar 157, and the strokes of the cam 151 cause cam fork rod 148 to oscillate about the bolt of the joint 154.

Adjusting the stitch location setting lever 129 to the center stitch position for which the edge 128 of the stitch location lever 129 is 'seated in the center tooth of the three teeth formed at the end of lever 120 (Fig. 5) and setting the switch knob 143 to zero causes the cam fork rod 14S in response to the rotary movement of the cam 151 to move pivotally about the pivot bolt 154 of the vertically disposed needle bar oscillator 156, because the guide member 147 is disposed in the direction of the rotary movement of the sliding member 149, The needle bar oscillator 156 thus edects no oscillatory movement with this adjustment so that the machine is set to effect straight forward stitching.

Rotating the switch knob 143 from zero position to the left causes the stitch locator guide member 147 to turn in the counterclockwise direction so that the eccentric fork rod 148 is imparted a forward movement in addition to the oscillatory movement around bolt 154 which causes the needle bar oscillator 156 to pendulate about its center position.

The greater the rotation of the guide member 147, the greater will be the lateral swinging movements of the needle bar oscillator 156 and thus also of needle bar 157. The triangular shape of the cam 151 causes the fork rod 148 to swing laterally only at predetermined partial sections of its course of rotation while the cam 151 is positioned in such a manner that the lateral swinging movement of the fork rod 143 takes place only when the needle bar 157 is in the area of its highest position.

The stitch location setting or adjusting is eected by means of the stitch locating lever 129. For example, if the setting is to be effected for shifting the stitch location to the left, then the stitch location lever 129 is brought to be seated in the upper groove or tooth of lever 120. In this manner the guide member 147 is moved about bolt 141 which, in turn, causes the fork rod 148 and thus the needle bar 157 to be displaced to the extreme left position. By simultaneous raising of the guide member 147 during the shifting, however, the sliding member 149 on fork rod 148 arrives in the lower part of the guide member 147 so that rotation of the knob 143 from the zero position causes the zig zag movements of the needle bar 157 to start always from the extreme left location.

lf the machine is intended to be operated as an ordinary Zig zag sewing machine the selector switch 118 is turned until the digit 0 is at the top as shown in Figs. 1 and 4. For this setting the cam 117 on cam shaft engages the lug 11S of the transfer lever 55 and restrains the shifting star 46 of the transfer system which is mounted on the shifting lever 44 of the transfer system from engaging the cam disk assembly or nest 8. Simultaneously the cam 119 on cam shaft 165 depresses arm 123 of the double armed lever 128* against the pressure of spring 126 so that the teeth 122 on its arm 121 are moved into engagement with the edge 128 of the stitch location adjustment lever 129. Thus the stitch location adjustment is set. The coupling bars 77, '78, 79 are raised by their

respective cams

114, 115, 116 on cam shaft 105 and are, therefore, disengaged from the

yokes

74, 75, 76 or the

supports

65, 66, 67.

By turning the shifting knob 40 counterclockwise for the adjustment of the design length the slide 21 is moved in the direction of the hand wheel of the machine by way of the eccentrically journalled pin 36 on switching 'shaft 37 and by way of the angular lever 32 and the pin 33 until the roller 16 of the double armed lever 11 is out of engagement with the conical cam 13 on the arm shaft 12 and the nose 3i) of the pusher rod 1th engages the stud 29. Thus the driving mechanism for the cam disk nest 8 is also disengaged.

In order to condition the mechanism for operation the aforementioned switches must again be manipulated, the sequence of the setting operations being immaterial. lt is suitable to effect the setting by means of a pattern hand book or the like, in which the adjustments for each pattern are indicated.

By rotating the shifting star 46 a suitable cam is selected from the cam disk assembly 8. Then by turning the shifting knob 41B counterclockwise the desired pattern or design length is adjusted. Thus the roller 16 of the double armed lever 11 is again brought into operative engagement with the conical cam under the effect of the tension of spring 14. Oscillatory movements are therefore imparted to the double armed lever when the mechanism is in operative position which are transferred by the pusher bar 1t) to the step switching mechanism 9 whereby the cam disk assembly S is operated in steps. Displacement of the axis 19 of the double armed lever 11 parallel to the arm shaft 12 when the shifting knob 40 is operated causes roller 16 to 'oe guided along the side of the conical cam 13, so that the step size of the advancement movement of the cam disk assembly 8 can be controlled in a continuous manner from zero to a maximum corresponding to the eccentricity of the cam 13.

For example, if it is desired for producing a predetermined design to set the yselector switch 110 to l it must be turned clockwise until the digit "1 is at the top and the spring biased ball 112:1 provided in the hub 113 engages and seats in a recess or detent 112 corresponding to the position of the selector switch 110. In this connection the cam 117 slides from the yoke 118 of the transfer lever 55 and releases it so that it may yield to the pull of the spring 56 and establishes operative engagement between the shifting star 46 and the cam disk assembly 8 by way of the

lever train

44, 49, 51.

Furthermore, the two

coupling bars

77 and 79 are raised by the

cams

114 and 116 on cam shaft 105, respectively, associated therewith, while the coupling bar 78 is released from its associated cam 115, so that it is enabled under the pressure of the overlying spring 131 to seat in the yoke 75 of the support 66 by means of its notch or recess 81. Thus the connection of the transfer lever 55 with the adjusting levers for the stitch width is established. By means of this adjustment, therefore, only the stitch width is controlled. The distance of the support 66 mounted upon the transfer lever 55 from its axis of rotation is so chosen that only half of the stitch width is controlled. Furthermore, the stitch location adjustment remains in operative position as in the setting of the selector switch 110 due to the conformation of the cam 119, so that it is possible, in addition, to adjust also the stitch location by means of the stitch location adjustment lever 129.

The further adjustment possibilities of the selector switch are briefly described hereinafter:

In the position 2 of the selector switch 110 also the coupling bar 77 engages the yoke 74 of the support 65 upon release by the cam 114 and establishes the connection with the stitch location adjusting lever 90. Accordingly the stitch location is controlled in addition to one half of the stitch width. For that reason the cam 119 in this position releases the double armed lever 120 again which under the influence of spring 126 disconnects the stitch location adjustment while the notches 122 are withdrawn from the reach of the edge 128 of the stitch location adjustment lever 129.

In the position 3 of the selector switch 110 the coupling bar 78 is raised by the cam 115 and only coupling bar 77 remains in operative connection with the transfer lever 55. Thus only the stitch location is controlled while the stitch width can be adjusted by hand. Also in this position the stitch location adjustment is disconnected.

In the position 4" of the selector switch 110 the coupling bar 77 is again raised by cam 114 while the cam 116 now frees the coupling bar 79 which in a similar manner engages the yoke 76 of support 67. The coupling bar 79 is also connected with the adjusting levers for the stitch width so that only the stitch width is controlled. The arrangement of the support 67 upon the transfer lever 55 is made in such a manner that now the stitch width is fully guided. By means of the cam 119 the stitch location adpjustment means is reconnected so that it is possible to effect the control of the stitch width from the stitch location left, right or center.

In the position 5 of the selector switch 110 the coupling bar 77 for the stitch location and the coupling bar 79 for the full-stitch width is released for seating in the

yokes

74 and 76, while the coupling bar 78 for one half Cil of the stitch is raised. Also in this position the stitch location adjustment means is disconnected.

The

adjustable lever connection

49, 51 affords the possibility of determining the swinging range of the transfer lever 55. It is furthermore possible-upon releasing screws S8, 96, 97 by correspondingly rotating the

eccentric bolts

83, 84, 85 to effect an accurate adjustment of the coupling bars 77, 78, 79.

Having now described our invention with reference to one operative embodiment thereof, we do not wish to be limited thereto but what we desire to protect by Letters Patent of the United States is set forth in the appended claims.

We claim:

l. Shifting and guiding mechanism for a sewing machine of the zig-zag type having a drive shaft and a needle bar oscillator operatively connected to said drive shaft; Said mechanism including a conically shaped cam mounted on said drive shaft a guiding device having a motion input portion, and a variable cam and follower means, variable cam drive means in operative engagement with said conically shaped cam, and impulse transfer means connected to said follower means, a stitch width adjusting means and a stitch location adjusting means operatively connected to said impulse transfer means, said cam follower means being movable in steps to transmit control impulses by way of said impulse transfer means and said stitch location adjusting means to the needle bar oscillator for producing embroidered designs, and said mechanism including selectively operable coupling bars disposed between said impulse transfer means and said stitch width and stitch location adjusting means, a selector switch having actuating members operative to shift selected ones of said coupling bars into and out of engagement with said impulse transfer means, and variable means operatively associated with said guiding device including a manipulating member operative to change the position of. said drive means relative to said cam on said shaft for continuous variation of the size of the control impulses for said guiding mechanism.

2. Shifting and guiding mechanism for a sewing machine of the zig-zag type having a drive shaft and a needle bar oscillator operatively connected to said drive shaft; said mechanism including a conically shaped cam mounted on said drive shaft a guiding device having a motion input portion, and a variable cam and follower means, variable cam drive means in operative engagement with said conically shaped cam, and impulse transfer means connected to said follower means, a stitch width adjusting means and a stitch location adjusting means operatively connected to said impulse transfer means, said cam and follower means being movable in steps to transmit control impulses by w-ay of said impulse transfer means and said stitch location adjusting means to the needle bar oscillator for producing embroidered designs, and said mechanism including selectively operable coupling bars disposed between said impulse transfer means and said stitch width and stitch location adjusting means, a selector switch having actuating members operative to shift selected ones of said coupling bars into and out of engagement with said impulse transfer means, and variable means operatively associated with said guiding device including a manipulating member operative to change the position of said drive means relative to said cam on said shaft for continuous variation of the size of the control impulses for said guiding mechanism, said coupling bars being spring biased toward said lever and said lever carrying a plurality of supports presenting yokes for selective engagement by the free ends of said coupling bars and said coupling bars being connected at their other ends to the stitch location adjusting means and to the stitch width adjusting means.

3. Shifting and guiding mechanism for a sewing machine of the zig-zag type having a drive shaft and a needle bar oscillator operatively connected to said drive shaft; said mechanism including a conically shaped cam mounted on said drive shaft a guiding device having a motion input portion, and a variable cam and follower means, variable cam drive means in operative engagement with said conically shaped cam, and impulse transfer means connected to said follower means, a stitch width adjusting means and a stitch location adjusting means operatively connected to said impulse transfer means, said cam and follower means being movable in steps to transmit control impulses by way of said impulse transfer means and said stitch location adjusting means to the needle bar oscillator for producing embroidered designs, and said mechanism including selectively operable coupling bars disposed between said impulse transfer means and said stitch width and stitch location adjusting means, a selector switch having actuating members operative to shift selected ones of said coupling bars into and out of engagement with said impulse transfer means, and variable means operatively associated with said guiding device including a manipulating member operative to change the position of said drive means relative to said cam on said shaft for continuous variation of the size of the control impulses for said guiding mechanism, said coupling bars being spring biased toward said lever and said lever carrying a plurality of supports presenting yokes for selective engagement by the free ends of said coupling bars and said coupling bars being connected at their other ends by means of eccentric bolts to the stitch location adjusting means and to the stitch width adjusting means.

4. Shifting and guiding mechanism for a sewing machine of the zig-zag type having a drive shaft and a needle bar oscillator operatively connected to said drive shaft; said mechanism including a conically shaped cam mounted on said drive shaft a guiding device having a motion input portion, and a variable cam and follower means, variable cam drive means in operative engagement with said conically shaped cam, and impulse transfer means connected to said follower means, va stitch Width adjusting means and a stitch location adjusting means operatively connected to said impulse transfer means, said cam and follower means being movable in steps to transmit control impulses by way of said impulse transfer means and said stitch location adjusting means to the needle bar oscillator for producing embroidered designs, and said mechanism including selectively operable coupling bars disposed between said impulse transfer means and said stitch width and stitch location adjusting means, a selector switch having actuating members operative to shift selected ones of said coupling bars into and out of engagement with said impulse transfer means, and variable means operatively associated with said guiding device includinU a manipulating member operative to change the position of said drive means relative to said cam on said shaft for con tinuous variation of the size of the control impulses for said guiding mechanism, each said coupling bar being provided with a biasing spring and each biasing spring being provided with a set screw or the like for biasing said bars toward said lever, said lever supporting a plurality of supports presenting yokes to receive the free ends of said coupling bars, said coupling bars being pivotally connected at their other ends to said stitch location adjusting means `and said stitch width adjusting means.

5. Shifting and guiding mechanism for a sewing machine of the zig-zag type having a drive shaft and a needle bar oscillator operatively connected to said drive shaft; said mechanism including la conically shaped cam mounted on said drive shaft a guiding device having a motion input portion, and a variable cam and follower means, variable cam drive means in operative engagement with said conically shaped cam, and impulse transfer means connected to said follower means, a stitch width adjusting means and a ystitch location adjusting means operatively connected to said impulse transfer means, said cam and follower means being movable in steps to transmit control impulses by way of said impulse transfer means and said stitch location adjusting means to the needle bar oscillator for producing embroidered designs, and said mechanism including selectively operable coupling bars disposed between said irnpulse transfer means and said stitch width and stitch location adjusting means, a selector switch having actuatling members operative to shift selected ones of said coupling bars into and out of engagement with said impulse transfer means, and variable means operatively associated with said guiding device including a manipulating member operative to change the position of said dri-ve means relative to said cam on said shaft for continuous variation of the size of the control impulses for said guiding mechanism, said selector switch including a cam shaft and said actuating members being cams mounted on said cam shaft, said cam shaft being also provided with a cam operative in a predetermined position of said cam shaft to disengage said stitch location and said stitch `width adjusting means from said guiding device, and a further cam operative to render effective holding means associated with said stitch location adjustment lever.

6. Shifting and guiding mechanism for a sewing machine of the zig-zag type having a drive shaft and a needle bar oscillator operatively connected to said drive shaft; said mechanism including a conically shaped cam mounted on said drive shaft a guiding device having a motion input portion, and a variable cam and follower means, variable cam drive means in operative engage ment with said conically shaped cam, and impulse transfer means connected to said follower means, a stitch width adjusting means and a stitch location adjusting means operatively connected to said impulse transfer means, said cam and follower means being movable in steps to transmit control impulses by way of said impulse transfer means and said stitch location adjusting means to the needle bar oscillator for producing embroidered designs, and said mechanism including selectively operable coupling bars disposed between said impulse transfier means and said stitch width and stitch location adjusting means, a selector switch having actuating members operative to shift selected ones of said coupling bars into and out of engagement with said impulse transfer means, and variable means operatively associated with said guiding device including a manipulating member operative to change the position of said drive means relative to said cam on said shaft for continuous variation of the size of the control impulses for said guiding mechanism, and locking means associated with said selector switch operative to retain said switch in the selected positions.

7. Shifting and guiding mechanism for a sewing machine of the zig-zag type having a drive shaft and a needle bar oscillator operatively connected to said drive shaft; said mechanism including a conically shaped cam mounted on said drive shaft a guiding device having a motion input portion, and a variable cam and follower means, variable cam drive means in operative engagement with said conically shaped cam, and impulse transfer means connected to said follower means, a stitch width adjusting means and a stitch location `adjusting means operatively connected to said impulse transfer means, said cam and follower means being movable in steps to transmit control impulses by way of said impulse transfer means land said stitch location adjusting means to the needle bar oscillator for producing embroidered designs, and said mechanism including selectively op'erable coupling bars disposed between said impulse transfer means and said stitch width and stitch location adjusting means, a selector switch having actuating members operative to shift selected ones of said coupling bars into and out of engagement with said impulse transfer means, and variable means operatively associated with said guiding device including a manipulating member operative to change the position of said drive means relative to said cam on said shaft for continuous variation of the size of the control impulses for said guiding mechanism, said selector switch including a cam shaft and said actuating members being cams mounted on said cam shaft, said cam shaft being 'also provided with a cam operative in a predetermined position of said cam shaft to disengage said stitch location and said stitch width adjusting means from lsaid guiding device, and a further cam operative to render effective holding means associated with said stitch location adjustment lever, said holding means comprising a double armed lever mounted externally of the machine housing, including one arm resting against said last mentioned cam and another arm extending downwardly externally of the machine having recesses endwise thereof for engagement by said stitch `location adjusting means.

8. Shifting and guiding mechanism for a sewing machine of the zig-zag type having a drive shaft and a needle bar oscillator operatively connected to saiddrive shaft, said mechanism including a conically shaped cam mounted on said drive shaft a guiding device having a motion input portion, and a variable cam and follower means, variable cam drive means in operative engagement with said conically shaped cam, and impulse transfer means connected to said follower means, a stitch width adjusting means and a stitch location adjusting means operatively connected to said impulse transfer means, said cam and follower means being movable in steps to transmit control impulses by way of said impulse transfer means and said stitch location adjusting means to the needle bar oscillator for producing embroidered designs, and said mechanism including selectively operable coupling bars disposed between said impulse transfer means and said stitch width and stitch location adjusting means, a selector switch having actuating members operative to shift selected ones of said coupling bars into and out of engagement with said impulse transfer means, and variable means operatively associated with said guiding device including a manipulating member operative to change the position of said drive means relative to said cam on said shaft for continuous variation of the size of the control impulses for said guiding mechanism, said variable means including said cam provided upon the drive shaft of the machine, a double armed lever pivoted on a stud, a pusher bar and a unidirectional stepping mechanism for rotating said guiding device, said double armed lever supporting a roller at one end for following said conically shaped cam and being pivotally connected to said pusher bar at the other end.

9. Shifting mechanism in accordance with claim 8, wherein a slide is mounted upon a supporting plate secured to the machine housing arm and supporting said stud and a switch is mounted upon the cover of the machine including a manipulating device for moving said slide.

10. Shifting mechanism in accordance with claim 9, wherein said manipulating device comprises a shaft and a bell crank lever having a member in operative engagement with said slide.

l1. Shifting mechanism in accordance with claim 8, including a pin on said ysupporting bar and a lug on said pusher bar for engagement by said pin in the position of said slide where said roller is disengaged from said conically shaped cam.

References Cited in the le of this patent UNITED STATES PATENTS 1,338,074 Eames et al Apr. 27, 1920 2,297,197 Bolter Sept. 29, 1942 2,713,838 Johnson et al July 26, 1955 2,755,754 Urscheler Iuly 24, 1956