US2824533A - Sewing machine needles - Google Patents

Description

Feb. 25,1958

mum 111A H. J. GOGSMAN 2,824,533

SEWING MACHINE NEEDLES Filed May 24, 1956 Fig.l

INVENTQR. WITNESS g- Herberf J Goosman 7 BY 4 m 3,

/ I E ZTfOR/VEY United States Patent '0 SEWmG MACHINE NEEDLES Herbert J. Goosman, Watchung, N. 11., a'ssignor to The Singer Manufacturing Company, :Eli'zabeth, N. 1., a corporation of New Jersey Application May 24, 1956, Serial No. 587,123

3 Claims. (Cl. 112-222) This invention relates to sewing machine needles.

In sewing machines, particularly of the high speed lock stitch type, it has been desirable under some conditions to set the sewing machine needle with the thread eye slightly angularly arranged in the direction of approach of the loop-taker loop-seizing beak as the beak rotates to loop-seizing position. When the needle eye is arranged in this manner the thread loop cast laterally of the needle during stitch formation extends in the same direction as the thread eye.

Conventionally, the needle used in these sewing machines comprises a longitudinal shank of circular cross section and a coaxial blade depending from the shank. The blades terminates in an eye-pointed work penetrating end and is provided on one side with the usual scarf arranged normal to the eye.

Considerable technique is required to set the above described needle to cast the thread loop in the desired direction since the circular cross-sectional shank of the needle does not provide any means for setting the needle in the needle bar with the thread eye predeterminately oriented. Accordingly, difiiculty is encountered when the needle is improperly set particularly when the thread eye is excessively turned in the direction of approach of the loop-seizing beak. With excessive turning of the thread eye a portion of the scarf surface normal to the eye extends into the path of movement of the loop taker and as the latter passes through the scarf during loop seizure it strikes the needle resulting in damage to the beak and also in needle breakage.

It is an object of the present invention to provide a sewing machine needle which will obviate the above difficulties.

Having in mind the above and other objects that will be evident from an understanding of this disclosure the invention comprises the devices, combinations and arrangements of parts as illustrated in the presently preferred embodiment of the invention which is hereinafter set forth in such detail as to enable those skilled in the art readily to understand the function, operation, construction and advantages of it when read in conjunction with the accompanying drawings:

Fig. 1 is a fragmentary front elevational view of a sewing machine showing the needle of the present invention mounted in a needle bar clamp and showing the relationship of the loop taker with the needle as the needle thread is cast laterally into a loop.

Fig. 2 is a greatly enlarged sectional view taken along the line 22 of Fig. 1.

Fig. 3 is an enlarged perspective view of a sewing machine needle embodying the features of the present invention.

Referring now to the drawings the sewing machine needle comprises a cylindrical shank 11 formed with a slabbed side or flat 12 extending along the full length of the shank. Coaxial with the shank 11 is a blade 13 having a pointed work penetrating end 14 and a thread eye 15 in proximity to the pointed end 14. The blade 13 is formed with a longitudinal thread groove 16 adapted to accommodate the needle thread r when the needle penetrates the material m during sewing. A scarf 17 is formed on the side of the blade substantially opposite from the groove 16. The thread eye 15 extends horizontally through the :blade 13 terminating at one end in the thread groove 16 and the other end in the scarf '17.

The scarf 17 is more or less of conventional shape and provides a longitudinal clearance groove in the blade through which the loop-"seizing beak 18 of the loop taker 19 passes during seizure of the needle thread loop L.

The scarf surface 20 in the vicinity of the thread eye 15 and across which the leading edge 21 of the loop taker 19 passes is slightly curved about the longitudinal axis of the blade 13. As shown in Fig. 2 in a plane substantially normal to the longitudinal axis of the blade and taken through the center of eye, which plane is hereinafter referred to as the cross-sectional plane, the scarf surface 20 is represented as being a convex surface approaching a planar surface substantially parallel with the slabbed side 12 and is bisected at 0 by a blade axis b lying in the cross-sectional plane, which axis is hereinafter referred to as the transverse blade axis b.

The thread eye 15, having a longitudinal axis r lying in the cross-sectional plane, is arranged in the blade with its axis t intersecting the transverse blade axis b at the point of intersection a forming an acute angle 10b. The angle tob represents the angle of inclination a of the thread eye 15 away from the blade axis b normal to a tangential plane p taken at 0 and to the plane of the flat 12. This angle may be varied within limits and it has been found that an angle of inclination of from 3 to 8 has been found to be sufiicient to achieve the desired improved results.

It is to be noted that in the form shown the plane p is substantially parallel to the fiat 12 and when the needle is inserted into a sewing machine needle clamp 22 the thread eye will be predeterminately positioned and will cast out the thread loop L in the direction of approach of the loop-seizing beak 18. It is to be understood, that the slabbed side 12 need not be positioned parallel with the plane p but may be arranged to cooperate with any particular design of needle setting means provided in the needle clamp 22. Under all conditions, however, the arrangement of the needle setting means and slab sided shank 11 must be such as to incline the eye 15 in the direction of approach of the beak 18 and maintain the tangential plane p parallel with the path of movement of the loop-seizing beak leading edge 21 to provide a clearance between the leading edge 21 and the scarf surface 20 and thereby prevent damage to the beak and needle breakage.

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

1. A sewing machine needle comprising, a blade, a shank formed on one end of said blade and provided with a flat, a work-penetrating point formed on the other end of said blade, a scarf formed in said blade adjacent said work-penetrating point and providing a scarf surface, and walls extending through said blade defining a thread eye opening into said scarf surface, the axis of said thread-eye through said blade lying in a plane normal to the longitudinal axis of said needle and forming an acute angle at said scarf surface with the transverse needle axis contained in said plane and perpendicular to said fiat.

2. A sewing machine needle comprising, a blade, a shank formed on one end of said blade and provided with a flat, a work penetrating point formed on the other end of said blade, a scarf formed in said blade on the same side of said blade as is said flat, said scarf providing a scarf surface, and walls extending through said blade end of said blade, a scarf formed in said blade on the 10 same side of said blade as is said flat, said scarf providing a scarf surface, and walls extending through said blade defining a thread eye opening into said scarf surface, the

axis of said threadeye through said blade lying in a plane normal to the longitudinal axis of said needle and forming an acute angle at said scarf surface with the transverse needle axis contained in said plane bisecting said scarf surface lying in said plane and perpendicular to said fiat.

References Cited in the file of this patent UNITED STATES PATENTS Hutchinson Apr. 12, 1887 Antclifi NOV. 12, 1940

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