US2806440A

US2806440A - Guiding mechanism for fabric frame

Info

Publication number: US2806440A
Application number: US583092A
Authority: US
Inventors: Schenkengel Emerich
Original assignee: GM Pfaff AG
Current assignee: GM Pfaff AG
Priority date: 1956-03-17
Filing date: 1956-05-07
Publication date: 1957-09-17
Anticipated expiration: 1974-09-17

Description

Sept. 7, 1957 E. SCHENKENGEL 2,806,440

. GUIDING MECHANISM FOR FABRIC FRAME Filed May '7, 1956 2 Sheets-Sheet 1 wrs/vrop Sept 7, 1957 E. SCHENKENGEL GUIDING MECHANISM FOR FABRIC FRAME 2 Sheets-Sheet 2 Filed May 7, 1956 INVENTOP United States Patent 9 GUIDING MECHANISM F011 FABRIC FRAME Emerich Schenkengel, Kaisersiautern, Germany, assignor to G. M. Pfaif A.-G., Kaiserslautern, Germany Application May 7, 1956, Serial No. 583,092

Claims priority, application Germany March 17, 1956 Claims. (Cl. 112-103) The invention relates to a material guiding frame for sewing machines in which a pantograph is combined with a movable parallelogram which carries the material frame.

Numerous material guiding frames of this type are known. In all embodiments known from the prior art the stationary pivot points of the system of jointed links are mounted upon the surface of the sewing machine table. If these known devices are used in conjunction with a Zig-zag sewing machine for embroidery work of circular designs, for example, rings, the resultant designs always have a more or less oval shape. The cause for that resides in the fact that the stationary pivots of the system are unable to change their position with respect to the oscillation plane of the needle bar.

For embroidering rings or annular sections of even width by means of a zig-zag sewing machine it is necessary that the stitches are disposed in a position radially with respect to the center. This requirement can only be met by guiding the work piece in a closed circle the center of which is located at the intersection of the oscillation plane of the needle bar with the plane of the movement of the work piece.

For this purpose devices have already been employed which have an adjustable center of rotation, for example, a mandrel, and which are able with the aid of the material moving dog of the machine to produce ringsor annular cut outs. The usefulness is limited, however, to circular patterns.

If it is desired to produce annular sections, such as scallops, in combination with any desired ornamental patterns or with monograms, there exists the possibility of swinging the sewing machine about its needle bar axis as a center point and to move simultaneously a fabric frame in the initially mentioned manner by means of a pantograph and a parallelogram to follow a pattern.

An arrangement of this type is already known, where a sewing machine is placed upon a turntable mounted in a table top in such a manner that the axis of the needle bar isin alignment with the center ofthe turntable. In this manner a special arrangement is created which can only be adapted for sewing machines having mounted .or built in motors. It is not possible, however, to produce a closed ring with radially extending stitches because the support for the fabric frame does not admit of a full 360 rotation of the sewing machine.

It is the object of the invention to provide a fabric frame guide which makes it possible to produce rings, ornamental patterns, monograms or the like in accordance with a stencil and with any desired transverse position of the stitches.

It is a further object of the invention to make it possible to embroider by means of a zig-zag sewing machine,

rings having equal width around their entire circumference. At the same time the mounting and the dismantling in flat machines and arm machines are to be rendered simpler and more rapid.

In accordance with the invention these objects are achieved in that the entire moving mechanism, a pantograph with a movable parallelogram carrying the fabric frame and a stencil or pattern holder, are secured to a support to be rotated 360 centrally with reference to the stitch hole in the stitch plate.

Suitably the support is mounted upon a superimposed stitch plate or adapter plate. The bearing or support may be an extension fastened to the adapter plate, which is provided with a needle stitch aperture. The support is preferably constituted of two bars disposed perpendicularly to each other, one of which carries a displacement member having the stationary pivot points of the moving mechanism and the angularly disposed other of which carries the pattern support.

Other features and objects of the invention will "become more apparent if reference is had to the accompanying drawings which illustrate one embodiment of the invention and in which Fig. 1 is a perspective view of the sewing machine with the fabric frame guide mounted;

Fig. 2 illustrates the fabric frame with a workpiece and the stencil in place;

Fig. 3 shows the fabric frame guide in a position where it has been turned to the right) Fig. 4 shows the support mounting in an exploded view;

Fig. 5 is a stitch pattern of a ring which has been produced on a work piece by means of zig-zag stitches without turning of the fabric frame guide, and

Fig. 6 shows the stitch pattern of a ring for the production of which the fabric frame has been rotated around the axis of the needle bar.

The zig-zag machine 1, which is sunk with its base plate 2 into the tabletop 3 is provided with a known embroidering mechanism where the 'em broidering arm 6 which is guided by the needle "bar 5 is fastened to the presser bar 4. i

The moving mechanism of a guide for the material frame comprises a pantograph having legs 7, 8, 9, 10a parallelogram connected to the pantograph at the

pivot points

11 and 12 and which is defined by the leg 10, a a leg 14 carrying the fabric frame 13, a leg 15 and an angle lever 16 which is joined to a compensating guide 17. The pantograph leg 7 extended beyond the pivot 18 supports a stylus 19 at one end, while the other end of the leg 7 is connected to the pantograph leg 9 at the pivot joint 20. The pantograph leg 9 which is extended beyond pivot point 12 and the free end of the cornpensating or balancing guide 17 are journalled at fixed

pivot points

21, 22 upon a slide member 23.

The slide member 23 is adjustably mounted and is connected to be fixed in position by means of a clamp lever 23a to a bar 25a of a support 24 in the form of a' square which receives an interchangeable stencil frame 26 upon a second bar 25b which extends at a right angle.

The support 24 (Fig. 4) is provided with a bore-27 in a recessed area 28. A top stitch plate 29 presents a stub member or stud '30 having a needle aperture 31 constitut ing the pivot joint for the support or square 24 which is secured in position by means of a resilient locking blade 32. This locking blade 32 rests in the recess 28 in;the support 24 and engages a groove 34 of the stub30 with its resilient checks 33. I

The top or superimposed stitch plate 29 is suspended in known fashion in the stitch plate 38 of the machine (Fig. 4) by means of abutments 35 and lugs' 36, 37 and is retained by the base plate slide 39] l 7 The fabric frame 13 is slidablein an elongated slot 40 in the leg 14 of the parallelogram and can be secured in position by means of a screw 41.

The stencil support 26 is provided with two guide grooves 42 which receive a stencil 43 (Fig. 2) and with fastening strip 44. A set screw 45 secured to the bar 25b and a knurled nut 46 serve the dual purpose of securing the stencil holder or frame 26 and the stencil 43 in place.

flu-operation the fabric frame guide mechanism is .secured to the machine by insertion of the legs .36, 37 of the .top stitch plate in the corresponding aperture of the stitch plate 38 and by sliding the base'plate slide 39, Upon securing the stencil 43 in place and upon stretching the fabric 47 in the frame 13 the machine is ready for -.op.eration.

The accurate locating of the initial position of the pattern on thefabric is accomplished by adjustment of the slide member 23 in two directions and of the fabric frame 13 in the slot 40 in the directions perpendicular to the first setting.

The rotatability of the fabric frame guide about the axis of the needle bar, as illustrated in Fig. 3, provides the possibility'of producing patterns with any desired transverse position of the stitches.

The pattern of a ring shown inFig. is obtained as already explained with the position of the fabric frame as shown in Figs. 1 and 2, i. e. when the support 24 extends parallel to the longitudinal axis of the machine.

A ring of even width as shown in Fig. "6 results from rotating the fabric frame guide during operation. However, if that type of procedure taxes the ability of the operator too much, it is possible to operate with abundantly sufiicient accuracy in sections, and with departures from the theoretical stitch position of the pattern which can hardly be noticed by the eye, for example, by making sections such as 48, 49 (Fig. 6) of approximately 45 by turning the fabric frame'guide from one average position of the section to the next. possible to carry out this method of operation continuously over the largest ;part of a ring.

Bytmeans of the fabric frame guide in accordance with the invention it is also possible in simplest fashion to obtain the most variegated stitch effects in connection with planar patterns.

Having now described my invention with reference to one preferred embodiment thereof and the manner in which it can be most advantageously employed, I do not wish to be limited thereto but what I desire to protectby Letters Patent of the United States is set forth in the appended claims.

I claim:

1. Guiding mechanism for the fabric frame of a sewing'machine adapted for embroidery work and having a stitch plate provided with an aperture, said mechanism comprising a support mounted over said stitch plate and having an aperture substantially concentric with said aperture in said stitch plate, a pantograph mounted on said support, a movable parallelogram pivotally connected to said pantograph, the fabric frame mounted on said parallelogram with its inner periphery around said apertures, and a stencil supporting frame secured to said support in operative relationship to a leg on said pantograph, said mechanismbeing rotatable 360 relative to the aperture of the stitch plate.

2. Guiding mechanism for the fabric frame of a sewing machine adapted for embroidery work and having a stitch plate provided with an aperture, said mechanism comprising a support mounted over said stitch plate and having an aperture substantially concentric with said aperture in said stitch plate, a pantograph mounted on said support, a movable parallelogram pivotally connected to saidpantograph, the fabric frame mounted on said parallelogram with its inner periphery around said apertures, and a stencil supporting frame secured It has been found to be to said support in operative relationship to a leg on said pantograph, said mechanism further including a superimposed stitch plate disposed over the stitch plate of the sewing machine and said support being mounted for pivotal movement on said superimposed stitch plate.

3. Guiding mechanism for the fabric frame of a sewing machine adapted for embroidery work and having a stitch plate provided with an aperture, said mechanism comprising a support mounted over said stitch plate and hav ing an aperture substantially concentric with said aperture in said stitch plate, a photograph mounted on said support, a movable parallelogram pivotally connected to said pantograph, the fabric frame mounted on said parallelogram with its inner periphery around said apertures, and a stencil supporting frame secured to said support in operative relationship to a leg on said pantograph, said mechanism further including a superimposed stitch plate disposed .over the stitch plate of the sewing machine and said support being mounted-for pivotal movement on said superimposed stitch plate, a :pivot stub having a needle aperturebeing supported on said superimposed stitch plate and extending through said aperture in said support.

'4. Guiding mechanism for the fabric frame of .a sewing machine adapted for embroidery work and having astitch plate provided'with an aperture, said mechanism comprising a'support mounted over said stitch plate and having an aperture substantially concentric with said aperture in said stitch plate, a pantograph mounted on said support, a movable parallelogram pivotally connected to said pantograph, the fabric frame mounted on said parallelogram with its inner periphery around said aper tures, and a stencil supporting frame secured to said support inoperative relationship to a leg on said pantograph, said .mechanism further including a superimposed stitch plate disposed over the stitch plate of the sewing machine and said support being mounted for pivotal movement on said superimposed stitch plate, a pivot stub'having a needle aperture being supported on said superimposed stitch plate and extending through said aperture in said support, said pivot stub having a circurnferential groove and a bifurcated :blade having engagement with said groove toretain said supportmember on said stub.

5. Guiding mechanism for the fabric frame of a sewing machine adapted for embroidery workand having a stitch plate provided with an aperture, said mechanism .comprising a support mounted over said stitch plate and having an aperture substantially concentric with said aperture in said stitch plate, a pantograph mounted on .said support, a movable parallelogram pivotally connected to said pantograph, the fabric frame mounted .on said parallelogram'with-its inner periphery around said apertures, and a stencil supporting frame secured to said support'in operative relationship to a leg on said pantograph, said mechanism further including a superimposed stitch plate disposed over the stitch plate of the sewing machine and said support being mounted for pivotal movement .on said superimposed stitch plate, a pivot stub having a needle aperture being supported on said superimposed stitch plate and extending through said aperture insaidsupport, said support being in the form of a square comprising .apair of perpendicularly disposed bars, a slide .member presenting a pair of fixed pivots being supported on one of said bars and said stencil frame being supported on the .other of said bars.

References" Cited in the file of this patent FOREIGN PATENTS 348,344 .France Feb. 6, 1905