US2619927A

US2619927A - Darning foot for sewing machines

Info

Publication number: US2619927A
Application number: US218731A
Authority: US
Inventors: Hofgesang William
Original assignee: Singer Co
Current assignee: Singer Co
Priority date: 1951-04-02
Filing date: 1951-04-02
Publication date: 1952-12-02
Anticipated expiration: 1969-12-02

Description

1952 w. HOFGESANG 2,619,927

DARNING FOOT FOR SEWING MACHINES Filed April 2, 1951 3 INVENTOR.

47 William Hofges-ang WITMS'S BY A TTORNEY Patented Dec. 2, 1952 EARNING FOOT FOR SEWING MACHINES William Hofgesang, Avenel, N. J assignor to The Singer Manufacturing Company, Elizabeth, N. 1., a corporation of New Jersey Application April 2, 1951, Serial No. 218,731

Claims. 1

The present invention relates to a darning foot for a sewing machine, and has for a primary object to provide a darning foot that is similar to known devices and comparable thereto in efiiciency of operation but which can be manufactured and sold more inexpensively.

A further object of the present invention is to provide a darning foot that is adapted to be secured to the needle-bar of a sewing machine in an improved manner.

Other objects will become apparent from an understanding of the present invention. A presently preferred embodiment of my invention by which these objects are attained, is hereinafter described in the following specification and illustrated in the accompanying drawings in such detail as will enable those skilled in the art to make and use my invention. It is to be understood that this specific embodiment is for illustration only and is not to be considered as a limitation.

In the accompanying drawings which form a part of this disclosure:

Fig. 1 is a fragmentary perspective view of the head end of a sewing machine with a darning foot that is made in accordance with the present invention mounted upon the needle-bar thereof.

Fig. 2 is a perspective view of the darning foot shown in Fig. 1.

Fig. 3 is a fragmentary vertical sectional view of the darning foot and needle-clamp of Fig. 1.

Fig. 4 is a horizontal sectional view of the darning foot and taken on the line 44 of Fig. 3.

In the drawings, there is illustrated a portion of a sewing machine head I. Mounted for vertical reciprocation in the head I in the usual manner are a presser-bar 2 and a needle-bar 3. The presser-bar 2 is provided with a threaded aperture 4 at its lower end that is intended to receive a screw for securing a presser-foot thereto when the machine is to be used for normal sewing. When a darning foot is used, to adapt the machine for darning, the presser-foot is removed as shown in the drawings. The needle-bar 3 carries a needle 5 at its lower end which is held in the usual recess in the needle-bar by a needleclamp 6 secured to the needle-bar by a set screw 1 and having an internally threaded radial boss 8 that receives a needle-clamp screw 9. The needle-clamp screw 9 is adapted to bear against a needle-clamping gib In which abuts against the needle and presses it into engagement with a wall of the needle-bar 3 to clamp the needle therebetween. This needle-clamping means is substantially the same as that disclosed in the U. S.

2 patent of Grieb, No. 1,896,047, and reference may be made thereto for a more detailed description of the construction and operation thereof.

A throat plate I I secured to the bed of the machine by screws l2 is provided with feed dog slots [3 through which a feed dog [4 projects to engage and advance the work past the stitching mechanism. The throat plate II also includes a needle aperture 15 through which the needle 5 is adapted to project to cooperate with a looptaker (not shown) located therebeneath in the formation of stitches. A slide plate [6 abuts against one edge of the throat plate It in the usual manner. Since the above construction is all conventional, it is not deemed necessary to expand this disclosure in relation thereto. It is to be understood that these elements, and the other elements of the sewing machine, may be of any well-known construction and the present invention is not limited to use with any particular sewing machine.

The darning foot that comprises the preferred embodiment of my invention as herein disclosed, generally indicated at ll, includues a carrierclamp [8 that has a base portion 19 provided with a needle-aperture 20 located centrally thereof. concentrically with the aperture 20, the base portion I!) is formed with a circumferential groove 2| that receives the upper coil of a conical spring 22 which is thus secured to the base l9 at substantially a right angle thereto. The lower coils of the spring 22 are wound around the reduced neck 23 of a stripper-foot 24 which is thus secured thereto at substantially a right angle to the axis of the spring and which includes an outwardly and downwardly flared foot 25 provided with a needle-aperture 26 and a thread-guiding aperture 21. The neck 23 of the stripper-foot is formed integral with the foot 25 and is flared outwardly and upwardly to receive and hold the lower coils of the spring 22. The needle-

apertures

20 and 26 in the carrier-clamp base [9 and stripper-foot base 25, respectively, and the coils of the spring 22 define an inverted substantially frusto-conical space in which the needle 5 is adapted to be positioned when operatively secured in the needle-clamp 6. The needle thread is led downwardly through a thread-guide l0 formed integral with the needle-clamping gib ID and depending therefrom, the thread aperture 21 in the stripper-foot 24, and then through the eye of the needle.

The carrier-clamp I8 is formed from an integral piece of sheet material that is spring-like in character. Bent from one side of the base I9 at substantially a right angle thereto along a line 28 is a shank portion 29. Bent laterally from the shank 29, preferably at a right angle thereto along a line 30 perpendicular to the line 29, is an car 31 provided with an aperture 32, the periphery of which is formed into a laterally extending flange 33. The aperture 32 is adapted to receive the needle-clamp boss 8 with the flange 33 closely embracing the same. It will be seen that by this construction, the carrier-clamp l8 may readily be properly positioned vertically on the needle-bar and secured thereon against vertical movement. Although the flange 33 is not essential to this function, it is preferably employed because of the larger contact area, afforded and the more stable connection that results. It will also be noted that it is necessary to remove the needle-clamp screw 3 in order to remove the carrier-clamp from the needle-bar.

The upper portion of the side edges of the ear 3| carries two opposed and

segmental spring clips

34 and 35 bent laterally therefrom to overhang the base I9. The top edge of the ear 3! is bent laterally to form a lip 36 which overlie the

spring clips

34 and 35. The free edge of the lip 36 is cut away to form a semi-circular recess 37 complemental to the needle-bar 3. The width of the ear 3| is preferably, although not necessarily, made such that the spring clips may be bent at substantially a right angle to the ear and still be so spaced as to resiliently embrace the needlebar 3. The lip 36 is also preferably bent at substantially a right angle to the ear 3|. The lip 36 extends over the spring clips 34 and 35 a distance suflicient to form a pocket with the inwardly turned ends of the spring clips, which pocket is adapted to receive the needle-bar 3. The length of the lip 36 is made such that when the carrierclamp is secured to the needle-bar, the lip 36 will abut against the needle-bar with the ear 3| maintained vertical, thus serving to laterally position the carrier-clamp with respect to the needle-bar.

From the above, it will be seen that the present device, embodying the teachings of my invention, can be manufactured very inexpensively. The carrier clamp, since it is made from a single blank of sheet material, can be shaped by stamping which is well adapted to mass production methods. It will also be seen that this darning foot can be readily attached to the needle-bar of a sewing machine and will be securely held thereon against all relative movement.

In operation, the present darning foot functions in the well-known manner. That is, after having removed the presser-foot of the machine from the presser-bar and secured to darning foot to the needle-bar, as shown in Fig. 1, the stitching mechanism of the sewing machine is operated in the usual manner. The darning foot resiliently urges the work into engagement with the work-support during that portion of the stitching cycle when the needle is being withdrawn from the work, to prevent flagging and thus to insure the proper formation of a thread loop.

It will be obvious that certain modifications may be made to the darning foot herein disclosed without departing from the spirit of this invention.

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

l. A darning foot for a sewing machine comprising a carrier-clamp formed from a blank of sheet material and having a base portion and an apertured ear portion, said ear portion being arranged at substantially a right angle to the base portion, opposed spring clips projecting from the ear portion to a position overhanging the base, a lip projecting from the ear portion in the same direction as the spring clips and at least a portion thereof being shorter than the spring clips, and a stripper-foot spring secured to and depending from the base portion.

2. A darning foot adapted to be secured upon a sewing machine needle-bar having a needleclamp including a radially projecting boss mounted upon the lower end thereof, said darning foot comprising a carrier-clamp having a base portion, an apertured ear portion secured to the base portion, said ear portion being arranged at substantially a right angle to the base portion and adapted to receive the boss of the needle-clamp, opposed spring clips secured to the ear portion and adapted to resiliently embrace the needle-bar, a lip carried by the ear portion and projecting therefrom in the same direction as the spring clips and at least a portion thereof being shorter than the spring clips, said lip being adapted to abut against the needle-bar, and a stripper-foot spring secured to and depending from the base portion.

3. A darning foot adapted to be secured upon a sewing machine needle-bar having a needleclamp mounted upon the lower end thereof and a boss projecting radially from the needle-clamp, said darning foot comprising a carrier-clamp formed from an integral piece of sheet material and having a base portion formed with a needleaperture and an apertured ear portion, said ear portion being arranged at substantially a right angle to the base portion and being adapted to receive the needle-clamp boss, a depending coil spring secured to the base portion and surrounding the aperture therein, opposed spring clips bent forwardly from the side edges of the ear portion and being adapted to resiliently embrace the needle-bar, and a lip bent from the top edge of the ear portion in the same direction as the spring clips and at least a portion thereof being shorter than the spring clips, said lip being adapted to abut against the needle-bar.

4. A darning foot for a sewing machine, comprising a carrier-clamp having an apertured base, a flat shank rising from said base and terminating in an apertured ear substantially normal to said shank and base, opposed and segmental spring clips extending from one side of said ear to overhang said base, a lip extending from said ear into overlying relation with said spring clips, said lip being shorter than said spring clips and having a segmentally recessed free end, and a stripper-foot carrying spring depending from said base. 7

5. A darning foot adapted to be secured upon a sewing machine needle-bar having a needleclamp mounted upon the lower end thereof and a boss projecting radially from the needle-clamp, said darning foot comprising a carrier-clamp formed from an integral blank of sheet material and having a base portion and an apertured ear portion, said base portion being adapted to be positioned below the needle-bar and substan tially perpendicular thereto and being provided with a needle-aperture, said ear portion being arranged at substantially a right angle to the base portion to project upwardly to one side of and substantially parallel to the needle-bar, a flange surrounding the aperture of said ear and adapted to receive the needle-clamp boss with the flange closely embracing said boss, opposed spring clips bent from the side edges of the ear portion to a position overhanging the base and being adapted to resiliently embrace the needlebar, a lip bent from the top edge of the ear portion in the same direction as the spring clips and at least a portion thereof being shorter than the spring clips, said lip being adapted to abut against the needle-bar, and a coil spring secured to and depending from the base portion so that when the darning foot is arranged in operative position on the needle-bar the axis of the spring will substantially coincide with a needle secured in operative position in the needle-clamp and projecting through the needle aperture in the base portion.

WILLIAM HOFGESANG.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 10 Number Name Date 1,169,236 Carr Jan. 25, 1916 1,193,408 Moses et a1 Aug. 1, 1916 1,452,687 Hemleb Apr. 2-4, 1923 2,525,956 Schribert Oct. 17, 1950