US2972319A

US2972319A - Apparatus for obtaining in a zig-zag sewing machine an automatic displacement of thefabric apt to be amplitude adjusted

Info

Publication number: US2972319A
Application number: US525935A
Authority: US
Inventors: Moro Antonio
Original assignee: F ILI BORLETTI SpA
Current assignee: F ILI BORLETTI SpA; Fili Borletti SpA
Priority date: 1954-08-06
Filing date: 1955-08-02
Publication date: 1961-02-21
Anticipated expiration: 1978-02-21
Also published as: GB784358A; BE540369A; CH328719A; DE1277649B; DE1028860B; FR1143022A

Description

t 00 w 2 h 7 00 w 2 e e W h W S E 6 S G A 4 Feb. 21, 1961 o o APPARATUS FOR OBTAINING IN A ZIG MACHINE AN AUTOMATIC DISPLACEMENT OF THE FABRICAPT TO BE AMPLITUDE ADJUSTED Flled Aug 2, 1955 Inventor An nio Mot-a w y W 2% 1 Mme Feb. 21, 1961 A. MORO APPARATUS FOR OBTAINING IN A ZIG-ZAG SEWING MACHINE AN AUTOMATIC DISPLACEMENT OF THE FABRIC APT TO BE AMPLITUDE ADJUSTED 6 Sheets-Sheet 2 Filed Aug. 2, 1955 mm 9? \m mm mm Inventor A-nZ o-n 4o Moro y v wneys Feb. 21, 1961 o o APPARATUS FOR OBTAINING IN A ZIGZAG SEWING MACHINE AN AUTOMATIC DISPLACEMENT OF THE FABRIC APT TO BE AMPLITUDE ADJUSTED Flled Aug 2, 1955 6 Sheets-Sheet 3 Inventor Anion [o ore y 8 @5 4 W? I ttorneys Feb. 21, 1961 MQRQ 2,972,319

APPARATUS FOR OBTAINING IN A ZIG-ZAG SEWING MACHINE AN AUTOMATIC DISPLACEMENT OF THE FABRIC APT TO BE AMPLITUDE ADJUSTED Filed Aug. 2, 1955 6 Sheets-Sheet 4 I n ventor AflfOTILb Mal-0 7 y 7 7, H WAttorneys I Feb. 21, 1961 o o APPARATUS FOR OBTAINING IN A ZIG-ZAG SEWING MACHINE AN AUTOMATIC DISPLACEMENT OF THE FABRIC APT TO BE AMPLITUDE ADJUSTED Flled Aug 2, 1955 6 Sheets-Sheet 5 Inventor A12 L 07? L o Mora y Z W 211M247 t Attorneys Feb. 21, 1961 A. MORO 2,972,319

APPARATUS FOR OBTAINING IN A ZIG-ZAG SEWING MACHINE AN AUTOMATIC DISPLACEMENT OF THE FABRIC APT TO BE AMPLITUDE ADJUSTED Filed Aug. 2, 1955 6 Sheets-Sheet 6 Inventor A'n Z 071 (O M -0 Antonio Moro, Milan, Italy, assignor to F.lli Borletti S.p.A., Milan, Italy Filed Aug. 2, 1955, Ser. No. 525,935 Claims priority, application Italy Aug. 6, 1954 6 Claims. (Cl. 112-158) The present invention relates to an apparatus, by

means of which it is possible, in a zig-zag sewing machine, to cause the displacement of the fabric to automatically respond to a previously determined cycle, said apparatus allowing at the same time for the adjustment of the amplitude of this displacement.

The apparatus according to the present invention is characterized by a cam being able to be rechangeably mounted on a rear extension of the shaft of the cam for producing the cross displacement of the needle bar for 'the zig-zag sewing operation, said cam positioned on the rear extension of said shaft having the task of actuating the means for driving the fabric feeder through alever, the pivot of which is displaceable, by a hand driven mechanism, preferably according to an arc of circle in such a manner as to be able to adjust through its displacement the oscillation that the lever driven by the cam transmits to the means for driving the fabric feeder.

The amplitude of the fabric feeder movement, ensured by the cam controlling its cycle, can thus be adjusted at will.

As to the means for driving the fabric feeder, it can consist in the mechanism of known kind generally employed in the sewing machines for causing said feeder to work.

However, it has been ascertained that in certain cases this kind of mechanism can give place to drawbacks capable of troubling the regular working of the machine.

For instance a remarkable strength is necessary for keeping said mechanism in a determined position and, as it is held in contact with the lever actuated by the automatic driving cam by means of a spring, the latter must be excessively strong, which jeopardizes the facility of movement of the machine.

The present invention provides, as complemental means of the apparatus forming the subject matter thereof, a device for controlling and adjusting the travel of the fabric feeder, which device, as it eliminates all the drawbacks of the mentioned mechanisms, assures to the sewing machine a perfect working.

This device is characterized by the fact that an oscillating fork, driven by an eccentric fixed on the upper main shaft of the sewing machine, carries parallel to its oscillation plane, a guiding pin, upon which is slidably mounted a runner pivoted on the link effecting the advancement of the fabric feeder, a cross lever or, more precisely, a lever with two branching arms extending therefrom in opposite directions, serving for varying the position of said runner on its guiding pin, said cross lever being mounted on the same oscillation pin of the fork and being arranged in such a manner as to be able to be actuated either through one of its branching arms, automatically, according to a previously determined cycle, by the lever driven by the cam turning in synchronism with the main shaft of the machine, or, through the-other branching arm, by a hand lever. A spring is provided to keep the cross lever adherent either to the hand driven ice lever or the lever driven by the cam; and as the runner, Whatever position it may be made to take up, that is also when it is brought on the guiding pin in the position of maximum distance from the oscillation center of the fork, under the maximum raising strength of the fabric, does not tend to go by itself to the zero position. Said spring can be very light, which is advantageous for the strengths of the cam, the movement facility of the machine and the regularity of the stitch.

Of course, the variation of the travel of the link driven by the runner or slider and consequently the variation of the stitch length depend on the position of said runner or slider.

In the described device the two drives of the adjustment by cam and by hand, can work either simultaneously or separately, in the latter case being excluded one or the other drive.

An embodiment of the apparatus according to the present invention is shown by way of example, as applied to a zig-zag sewing machine with variable sewing cycle of the kind as in my copending patent application Serial No. 525,177, in the annexed drawings, in which:

Fig. 1 is a longitudinal section of the zig-zag sewing machine;

Fig. 2 is across section of the same according to the line A-A of Fig. 1.

Fig. 3 is a cross section of the same according to the broken line B-B of Fig. 1.

Fig. 4 is a cross section according to the line CC of Fig. 1.

Fig. 5 is a cross half section showing a modification of Fig. 4 concerning the mounting of the cam for displacing the fabric. 7

Fig. 6 is a cross half section showing another modification of Fig. 4 concerning the mounting of the cam for displacing the fabric.

Fig. 7 shows a partial longitudinal section of the machine according to the line D-D of Fig. 4.

Fig. 8 shows in longitudinal section the device for controlling the fabric feeder, said device being applied onto the machine.

Figs. 9 and 10 are two cross sections according to the line EE of Fig. 8, said figures showing said device in two different working conditions.

Fig. 11 is a partial rear view according to the arrow F of Fig. 10. 1

Fig. 12 shows the particular of the runner or slider.

The main shaft 1 (Fig. 1), mounted in the upper portion of the frame 2 of the machine, transmits a reciprocating up and down movement to the needle bar '5 by means of the crank pin 3 and the spring connecting rod 4. The cross movement for the zig-zag sewing operation is transmitted to the needle bar by the same shaft 1 throughthe worm 6 and worm wheel gear 7, the shaft 8, a cam 25 mounted on the shaft 8, the two arms lever 9, 10 actuated by said cam, the oscillating support 11 actuated by the arm 10 of said lever, the shaft 12 sliding in said support and the rod 13 pivoted, at one of its ends, on the shaft 12 and connected, at the other end, to the support 14 of the needle bar, fixed in 15 to the frame 2 by means of the small elastic plate 16. The main shaft 1 (Figs. 1 and 2) also actuates, by means of its crank 17, the link 18, the lever 19, the shaft 20 and the bevel toothed wheels 21 and 22, the hook 23, which cooperates with the needle 24 for producing the sewing operation. The cam mounted and secured on the shaft 8 for forming in known manner the zig-zag sewing is that indicated in the drawings (Figs. 1 and 3) with 25. On the hub of this cam, however, a second cam 26 (Fig. 3) can be mounted in such a manner as to be able to be changed for varying the zigzag cycle and for passing from one sewing cycle to another one while the lever 9-10 can be transferred from one of said cams to the other one, by causing it to slide by an actuation member (not shown) on both its rotation pin 27 and the pin 28, which is carried by the support 11 and on which said lever is mounted by the fork end of its arm 10. The oscillation pin 29 of the support 11 is connected, by means of the support 30 and the arm 31 to the piece 32 pivoted on the shaft 33 and carrying the small plate 34 fixed thereupon, said plate at its upper end being rigidly connected to the maneuvering button 35. On the pivoting pin 36 of the rod 13, which is located on the shaft 12 is pivoted the arm 37, which at its lower end is pivoted by means of the pin 38 on the sleeve 39, the latter having a projection 40 upon which is mounted the stem 41 of an actuating button 42. Thus, by acting on the buttom 35, the angular position of the support 11 and therefore the cross origin of the zig-zag stitch is varied. By acting on the button 42, one varies, by displacement of the shaft 12, the position of the pin 36 and the rod 13 with respect to the support 11 and, therefore, the oscillation amplitude of said rod, with consequent variation of the amplitude of the sewing zig-zag. The maneuvering movement of the button 42 in the relating window can be limited by stops 43 applied in said window and blocked each by a button 44 having threaded stem. These stops, however, can be surmounted by the button 42, when it is pushed towards the interior against the action of the spring 45, so as to bring in correspondence with said stops the portion 41' of the stem 41. Thus, button 42 is free to move to a new position, whereupon button 42 is released, and spring 45 moves the stem 41 back into engagement with the stops 43.

According to the present invention, on the rear extension 8' of the shaft 8 (Fig. 4) is mounted a cam 46 locked by means of a nut 47 on a flange 48, which can be either fixed on the shaft 8 (Fig. 4) or mounted in a bearing 49 fixed to the frame 2, said flange being connected to a hub 50 fixed on 8', in such a manner as to be able to be caused to turn by means of either a joint 48 (Fig. or a gear 50' (Fig. 6). In the last case the advantage is obtained that the speed ratio between the shaft 8' and the cam 46 can be varied by varying the ratio of the teeth on hub 50 and flange 48.

The periphery of the cam 46 (Fig. 7) is kept in contact with the small pin 51 carried by the arm 52 of the two

arm lever

52, 53, the other arm of which carries a small pin 54 capable of being brought into contact with the projection 55 of the lever 56 driving the mechanism of known kind which transmits the movement to the fabric feeder.

The

lever

52, 53 is pivoted at 57 on a support 58 pivoted on a shaft 59 and rigidly connected to an arm 60 bearing on an eccentric 61.

With the described arrangement the rotation of the cam 46 causes a reciprocating movement of the

lever

52, 53 and, therefore, of the projection 55 which by means of a spring 62 (Fig. 2) is kept in contact with the small .pin 54. Correspondent displacements are thus repeated by the projection 55 and thus by the lever 56, so that to the fabric can be imparted forward and backward displacements, said displacements responding to the cycle determined by the shape of the cam 46. By adjusting the angular position of the eccentric 61 by means of the button 63 and thus displacing by the arm 60 the angular position of the pin 57 on an are 64 (Fig. 7), the displacemerits of both the pin 54 and the projection 55 can be varied both in absolute value and with respect to the movement of the needle bar, so as to obtain by the same cam displacements of the fabric of different amplitude according to the position given to 61.

Under the angular positions that the eccentric 61 can be given, there is one at least for which the pin 54 is completely removed from the projection 55, so that it has no more influence on the advancement of the fabric. Under these conditions, the lever 65 can be caused to work, by maneuvering it by hand by means of the button 66, said lever through the pin 67 coming then into contact with the lever 56 is moved free of the pin 54 and biased by the spring 62. The displacement of the fabric takes place by hand, in the manner known for the sewing machines.

The cam 46 (Fig. 4) can be easily substituted with any other cam having a different profile simply by unscrewing the nut 47. Between the cam 46 and the flange 48 can be arranged a spring 68 to facilitate the removal of cam 46. It is not necessary to remove the cam 46, when it is already mounted, for passing from the drive for displacing the fabric by cam to the drive for displacing it by hand.

In order to be able to effect the mounting and the re moval of the cam 46, in the rear wall of the frame 2, opposite thereto, is provided a window closed by a plate 69, said window corresponding to the one closed by the plate 70, which is located in the opposite wall for both the mounting and the removal of the removable cam 26 for the zigzag sewing operation.

The lifting of the fabric feeder 71 (Figs. 1 and 2) is effected by a cam 72 mounted on the oscillating shaft 20, which drives the hook 23. On the cam 72 bears a lever 73, pivoted at 74, on the other end of which the pin 76 is mounted. The end 77 of the movable support 78 of the fabric feeder 71 bears on this pin 76, a spring 79 keeping the support, by means of the lever 73, biased towards the cam 72. The pin 76 is axially slidable in such a manner as to be able to be disengaged from the end 77 of the support 78, thus removing the fabric feeder from the drive of the cam 72. The fabric feeder then remains in a downward position and the machine can effect embroidery work for which the fabric is displaced by hand.

The pin 74 is secured in the bush 30, which is adapted to be displaced and fixed in a position chosen in any manner on the pin 81 by means of screw By this system the projecting portion of the fabric feeder can be easily adjusted.

In the foregoing description it was assumed (Figs. 1 to 7), that the means for driving the fabric feeder might consist of the mechanism as usually employed to this end in the sewing machines of known kind.

However, as it was already stated, a better drive of the fabric feeder ensuring a perfect working of the machines, is obtained by means of the device forming the subject matter of the invention, which is illustrated as applied on a zig-zag sewing machine in Figs. 8 to 12.

In this device, the fork 82 is caused to oscillate on the pin 83 by the cam 84 mounted on the upper shaft 1 of the machine. A guiding pin 85 is fixed to the

projections

86, 87 rigidly connected to the fork 82.

The guiding pin 35 accomplishes about the pin 83 the same oscillations of the fork 82, that is it displaces itself, at each revolution of the cam 84 from the position X-X to the position Y-Y, returning to the position XX at the end of each revolution. If the center 92 of the runner or slider 88, which is displaced on the pin 85 from one end 89 to the other end 99 of said pin and vice versa, coincides with the axis of the pin 83, said slider remains immovable and the link 91, pivoted at 92, does not receive any axial displacement. If the center 92 of the runner or slider 88 is displaced towards the end 86, it receives displacements from X to Y according to the arrow 93 and returns. If the center 92 of the runner or slider 88 is displaced towards the end 87, it receives opposed displacements, that is according to the arrow M and returns.

The link 91 consequently receives corresponding displacements. As the link 91 is connected by means of the parts 95, 96 (Fig. 2) to the support 73 of the fabric feeder 7i, consequently also said feeder 71, in synchronism with the feeder lifting means 75, moves from a forward position to a backward position or from a backward position to a forward position, in response to the position of the runner or slider 88 on the pin 85. The more the runner or slider 88 is displaced from the pin 83, the greater will be its displacement in the sense of the

arrows

93, 94 and the greater will be the travel of the link 91 and consequently of the feeder 71.

It is sufiicient to displace the runner or slider 88 from the pin 83 of a given distance and towards the determined side with respect to the pin 83 for obtaining the desired displacement length and direction of the fabric for each stitch.

As the maximum necessary inclination of the guiding pin 85 upwards or downwards with respect to its middle position -0 is small, that is of about 6, it is easy to understand that it is not necessary to have a great strength for causing the runner or slider 88 to slide on the pin 85, and that moreover the oscillation of the fork 82 does not tend to make the runner or slider 88 return to the central position (axis 83), so that a small force is sulficient for keeping said runner in any determined position.

The displacement of the runner or slider 88 is caused by the cross lever 97 pivoted on the pin 83. The projection 97 carries a pin with a slipper 98 which is retained in the fork 99. The fork 99 is secured to the link 91 on the upper portion of which is pivoted the runner or slider 88 which is held on the opposite side by the small plate 99. 1

The drive can be imparted to the lever 97 by two separate parts, of which, one 100 is connected to a lever 101 adapted to be actuated by hand from the outside of the frame and the other 102 is actuated by the lever 52 automatically driven by the cam 46 (Figs. 4 to 6). Either the part 100 or the part 102 can be inoperative independently of the other part, leaving only one part in operation. The adherence of one of the projections 97" and 97" against the

part

100 or 102, respectively, is maintained by a spring 103, one end 103 of which is fixed to the support 104, while the other end 103 is connected to the lever 97, said end 103" of said spring keeping said lever pushed against either the pin 100 or the pin 102 of the driving lever.

Assuming that the part 102 may be inoperative, the spring 103 will hold the projection 97" against the part 100. When this part has been displaced, the projection 97" will follow it and consequently the slipper 98 will be displaced, said slipper constraining the fork 99 to move and the runner 88 to slide upon the guiding pin 85 within the limits 89-90. According to the position of the part 100, the runner or slider 88 will accomplish one determined stroke, said stroke being repeated by the fabric feeder.

If, on the contrary, the part 100 is inoperative and the part 102 is put in operation, this part 102 accomplishing automatic cyclic displacements, will compel the projection 97" to make corresponding displacements and similarly the fork 99, the link 91 and, consequently, the fabric feeder, the stroke amplitude and direction of Which will continuously vary for each stitch according to the shape of the cam driving the part 102.

The device will also work if both

parts

100 and 102 are made operative, without any inconvenience being caused in the working, the one or the other of the

parts

100, 102 effecting then the task of stroke limiter of the lever 97 and consequently of length limiter of the stitch.

It is clear that the construction of the parts hereinbefore described can vary from that shown in the drawings, the mechanism resulting from their combination still remaining withinthe scope of the invention.

What I claim is: I

1. In a zig-zag sewing machine having a frame with a needle mechanism and work feeder therein, with two replaceable cams for the execution of pattern sewing, one of which cams is for driving the transverse displacements of the needle and the other of which cams is for driving the displacements of the work feeder, means for operatively connecting said second cam to the feeder comprising a two-armed lever, one arm of said lever carrying a cam follower for receiving movement from said second cam, means operatively connected with the other arm of said lever and to said feeder for controlling the movement of the feeder, a second two-armed lever, means swingably mounting said second lever on the machine frame, means pivotally mounting the first lever on an arm of the second two-armed lever, and a manually operated eccentric cam engaging the other arm of said second lever whereby operation of the eccentric cam results in a movement of the last-mentioned means of the first two-armed lever along a circular line and in a corresponding variation of the movements of the feeder.

2. A zig-zag sewing machine according to claim 1 wherein the means connecting the first lever to the work feeder comprises a cross lever having three arms, a hand-operated pin mounted on said frame and being in engagement with a first arm of said cross lever, said second arm of the first two-armed lever having a pin, the second arm of said cross lever being in engagement with said pin, an oscillating link operatively connected to the second arm of said first lever, said link having a fork engaging the third arm of said cross lever, to thereby transmit to the oscillating center of said link the displacements imparted in turn by the other two arms of said cross lever.

3. A zig-zag sewing machine according to claim 2, wherein a light spring keeps the cross lever adherent to either the hand-operated pin or the eccentric cam.

4. A zig-zag sewing machine according to claim 2, wherein said hand-operated pin operates said cross lever to impart simultaneously or separately to said work feeder controlling and adjusting drives from said eccentric cam and said hand-operated pin.

5. A zig-zag sewing machine according to claim 2, further comprising an oscillating guiding pin having a small angle of oscillation, a slider slidably mounted on said guiding pin, said oscillating link connected to said slider whereby the oscillation produced by the guiding pin on said work feeder is small to prevent autonomous displacements of the slider on the guiding pin.

6. A zig-zag sewing machine according to claim 2, wherein a slipper is mounted at the end of the third arm of said cross lever and arranged to slide in said fork.

References Cited in the file of this patent UNITED STATES PATENTS 696,039 Grothe Mar. 2, 1902 1,611,372 Rader Dec. 21, 1926 2,114,075 Gellman Apr. 12, 1938 2,305,556 Pinkvoss Dec. 15, 1942 2,653,557 Casas-Robert et al. Sept. 29, 1953 2,755,754 Urscheler July 24, 1956 UNITED STATES PATENT. OFFICE CERTIFICATE OF CORRECTION Patent No. 2,972,319 February 21 1961 Antonio Moro It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent shouldread as corrected below.

d Column 2 line 6 for "positions Said" read position sal Signed and sealed this 151; day of May 1962.

(SEAL) Attest:

DAVID L. LADD ERNEST W, SWIDER Commissioner of Patents Attesting Officer