US3012528A

US3012528A - Zigzag sewing mchine having operating means for adjusting the stitch width and the position of the stitching field

Info

Publication number: US3012528A
Application number: US827888A
Authority: US
Inventors: Gegauf Fritz
Original assignee: Fritz Gegauf AG
Current assignee: Fritz Gegauf AG
Priority date: 1958-07-17
Filing date: 1959-07-17
Publication date: 1961-12-12
Anticipated expiration: 1978-12-12
Also published as: DE1089252B; CH363222A; FR1219858A

Description

1961 F. GEGAUF 3,012,528

ZIGZAG SEWING MACHINE HAVING OPERATING MEANS FOR ADJUSTING THE STITCH WIDTH AND THE POSITION OF THE STITCHING FIELD 2. Sheets-Sheet 1 Filed July 17, 1959 IHH lllll INVENTOR- FRITZ GEGAUF BY Dec. 12, 1961' F. GEGAUF 3,012,528

ZIGZAG sEwING MACHINE HAVING OPERATING MEANS FOR ADJUSTING THE sTITcH WIDTH AND THE POSITION OF THE sTITcHING FIELD Filed July 17, 1959 2 Sheets-Sheet 2 Utcd States Patent 3 012,528 ZIGZAG SEWING MAHINE HAVING OPERATING MEANS FOR ADJUSTING THE STITCH WIDTH AND THE POSITION OF THE STITCHING FIELD Fritz Gegauf, Steckborn, Switzerland, assignor to F rrtz Gegauf Aktiengesellschaft Bernina-Nahmaschinenfabrik, Steckboru, Switzerland Filed July 17, 1959, Ser. No. 827,888 Claims priority, application Switzerland July 17 1958 4 Claims. (Cl. 112-158) In heretofore known zigzag sewing machines the operating means for regulating the stitch width and the position of the stitching field, that is the extent for which the central alignment of the sewing stitches is shifted to the right and left, are arranged at the front wall of the upper sewing machine arm each on a separate axis or also coaxially. The borings in which are arranged the axles for such operating means must be worked separately in the production cycle of the sewing machine with corresponding waste of time and raise of the costs. The mounting of such operating means moreover is complicated and very expensive owing to the position of their borings with respect to the zigzag mechanism and in view of the 'required bearing and connecting elements.

It is a prime object of the present invention to reduce the cost of manufacture and assembly of a sewing machine by arranging at least one of said operating means for the stitch width and for the position of the stitching field on a common axle necessarily present for another member of the machine.

According to the present invention this object is attained by arranging one or the other of said operating means or both coaxially with respect to each other on the driving shaft for the zigzag mechanism of the machine.

Other features and advantages of the invention will become apparent from the following description of a preferred embodiment thereof, in which reference will be made to the accompanying diagrammatical drawings, in which:

FIGURE 1 is a partial elevational view of a zigzag sewing machine showing the operating means for adjusting the stitch width, the position of the stitching field and the stitch length.

FIGURE 2 is a view similar to that of FIGURE 1 but with the front wall broken away in order to show the drive for the zigzag mechanism.

FIGURE 3 is a cross-sectional view taken along the line I-I in FIGURE 2, and showing the operating means for the stitch width and for the position of the stitching field, and

FIGURE 4 is a horizontal sectional view of FIGURE 2. Referring to the drawing reference numeral 1 designates I the L-shaped upperarm of a sewing machine having a removable cover 2. Reference numeral 3 designates the base plate of the sewing machine and reference 4 the drive wheel of the machine. At the front wall of the arm 1 there are arranged: the operating member 5 for adjusting the stitch width and its graduation 6, the operating member 7 for adjusting the position of the stitching field with an arrow 8 and a lever 9 for adjusting the stitch length. An abutting screw 10 arranged below the drive wheel 4 serves to limit the stitch length. The drive wheel 4 is releasably connected in a known and not represented manner with the main drive shaft 11 arranged in the arm 1. A driving gear 12 for the zigzag mechanism is rigidly mounted by means of a screw 13 on the shaft 11. A driven gear 14 revolving at one half of the speed of main shaft 11 forms one part with the zigzag eccentric 15 and is loosely mounted on a supporting axle 16. The eccentric 15 abuts a set ring 17 secured to the axis 16 ice 7 by means of a screw 1*8 while the gear 14 abuts with its side opposite the eccentric a groove or star segment 19 secured to the axle 16 by means of a screw 20. The eccentric 15 is enclosed by a fork '21 rigidly connected 'by means of a screw 23 with its tilting axle 22 mounted in an eye 24 of the arm 1. The pendulum movement imparted to the fork 21 by the eccentric 15 is transmitted to a swinging lever 25 secured to the axle 22 by means of a screw 26.

A stitch width link 27 is tiltably mounted in lever 25 through a tap 28. The slide member 29 of the link 27 is connected on the one hand by an arm 30 with the not represented needle bar link and thus with the needle and on the other hand by an attachment 31 and through a screw 32 is articulated to the lever 33 for adjusting the stitch width. The adjusting lever 33 has a long hub 34 by means of which it is pivotally mounted in a bushing 56 secured to the arm 1 by means of a screw 35. The

of a tap 40. The position of the segment 19 having three grooves for left position L, middle position M and right position R is secured by a pin 41 arranged in a boring in the arm 1 and engaging under the action of a spring 42 one of the grooves depending of the position of the segment 19.

In operation the drive wheel 4 entrains the shaft 11 and imparts through the helically geared

wheel pair

12, 14, the zigzag eccentric 15 and the fork 21 a pendulum movement to the link 27. If the operating member 5 for adjusting the stitch width, which is mounted on axle 16, is displaced to a position departing from the zero position and indicated on the graduation, the adjusting lever 33 moves the slide member 29 of the link 27 to a corresponding position spaced from the zero position. The army 30 pulls the needle to a greater or to a smaller needle deflection or amplitude. The modification of the needle amplitude may also be effected during the sewing operation. In order to modify the position of the stitching field, i.e. in order to shift the stitches to the right or the left of the normal needle path, the operating member 7 also mounted on the same axle 1'6 and provided with the arrow 8 is pivoted in such manner that the arrow is directed to the left, to the middle or to the right, whereby the stitching field position is correspondingly adjusted. Thereby the pin 41 engages one of the grooves L, M, R of segment 19 and secures the desired position. The member 39 is articulated as well to the segment 19 as also to the link 27 which in turn is articulated to the swinging lever 25. The member 39 displaces the zero position of the link 27 in accordance with the adjustment to the left or to the right into the desired position and thus modifies the stitch field position of the needle.

The illustrated embodiment may of course be modified by arranging only the operating member for the stitch width or only the operating member for the stitching field position on the driving shaft of the zigzag mechanism without departing from the scope of the invention as defined in the claims.

I claim:

1. In a zig-zag mechanism for a sewing machine ineluding an oscillatable slide link, a slide slidable on said link and connectable to a needle bar to shift the bar during its reciprocation, the improvement comprising a supporting axle, a driving member rotatable on said supporting axle, means connected to said driving member and said slide link for oscillating said link, a first operating member rotatable on said driving axle connected to said slide and rotatable to shift the position of said slide to vary the stitch width, a second operating member afiixed to said supporting axle to rotate said axle, and means on said supporting axle connected to said slide link to change the position of said slide link upon movement of said second operating member and said axle to vary the field position.

2. In a Zig-zag mechanism according to claim 1, wherein said first operating member includes a sleeve rotatable on said supporting axle, and a knob affixed to said sleeve.

3. In a Zig-zag mechanism according to claim 1, wherein said second operating member includes a knob connected to one end of said supportnig axle.

4. In a zig-zag mechanism according to claim 1, wherein said driving member is a sleeve having a gear portion at one end and an eccentric portion at the opposite end connected to said slide link for oscillating said slide link.

References Cited in the file of this patent UNITED STATES PATENTS 1,997,411 Eames Apr. 9, 1935 2,047,754 Tiesler July 14, 1936 2,653,557 Casas-Robert et al Sept. 29, 1953 2,757,626 Fujita Aug. 7, 1956 FOREIGN PATENTS 792,784 Great Britain Apr. 2, 1958