US3643613A

US3643613A - Device for guiding the needle thread of sewing machines

Info

Publication number: US3643613A
Application number: US751422A
Authority: US
Inventors: Lothar Schwehm
Original assignee: GM Pfaff AG
Current assignee: GM Pfaff AG
Priority date: 1967-09-23
Filing date: 1968-08-09
Publication date: 1972-02-22
Anticipated expiration: 1989-02-22
Also published as: DE1973757U; GB1163510A

Abstract

A device for guiding the needle thread of sewing machines including a lug having a thread guide eyelet mounted on the needle bar and a frame mounted on the stepper foot shaft, which frame has a crossbar that extends transversely proximate the path of the needle and is overlapped by the thread guide eyelet when the needle is in the lower position. This device serves to seize the excess thread between the needle eye and the thread carrier, thus facilitating the formation of the thread loops.

Description

United States Patent Schwehm 1 Feb. 22, 197 2 [54] DEVICE FOR GUIDING THE NEEDLE [56] References Cited THREAD OF SEWING MACHINES UNITED STATES PATENTS [72] Schwehm Kmserslaumm 363,656 5/1887 Littlejohn ..1 12/245 827,654 7/ 1906 Onderdonk ..l12/245 [73] Assignee: G.M. Piaff AG, Kaiserslautem Pfalz, Germany Primary Examiner-J1. Hampton Hunter [22] Filed: Aug. 9, 1968 AttorneyRobert H. Jacob [21] Appl. No.: 751,422 I [57] ABSTRACT [30] Foreign Application Priority Data A device for guiding the needle thread of sewing machines including a lug having a thread guide eyelet mounted on the nee- Sept. 23, 1967 Germany ..P 30 120/52 dle bar and a frame mounted on the Stepper foot Shaft, which frame has a crossbar that extends transversely proximate the l path of the needle and is overlapped by the thread guide eyelet [58] when the needle is in the lower position. This device serves to Field ofSearch ..ll2/218 R, 254,255,241, 245

seize the excess thread between the needle eye and the thread carrier, thus facilitating the formation of the thread loops.

2 Claims, 1 Drawing Figure BACKGROUND OF THE INVENTION The present invention relates to the guiding of the needle thread in sewing machines. More in particular, the present invention is concerned with a device for guiding the needle thread, with a thread guide eyelet arranged on the needle bar and a frame, the center part of which extends transversely of the path of the needle.

Devices of this type serve to avoid faulty stitching and the breaking of threads, especially in the formation of stitches outside of the material being sewn, in that-they favor the formation of thread loops above the stitch plate. They thereby prevent a faulty form of the thread loop at the eye of the needle for the entrance of the looper point.

SUMMARY OF THE INVENTION It is therefore, an object of the present invention to provide a thread-guiding device, which insures a correctly functioning, safe threading operation with a simple form of construction, and which in addition does not have any components that are subject to wear.

Therefore in accordance with the invention, the frame is mounted on the housing of the sewing machine, its center part or crossbar extends between the bath of the thread guide eyelet and the path of the needle eye, and when in the lower position, the thread guide eyelet overlaps the path of movement of the center part of the frame.

As a result of this arrangement of frame and thread guide eyelet, the needle eye is located above the midportion of the frame during the threading operation, which, as is well known, takes place in the area of the upper end position of the needle bar. In any event the needle thread is thereby guided on a correctly functioning course in the area of the thread-guiding apparatus, without special precautions being necessary on the part of the operating personnel.

By providing the frame with one or more finger guards, the apparatus allows itself to be used simultaneously as protection against finger injuries sustained by the operating personnel from the needle while sewing.

BRIEF DESCRIPTION OF THE DRAWINGS Further advantages and details of the invention will become apparent by reference to the accompanying drawing which illustrates an embodiment of the invention.

DESCRIPTION OF THE INVENTION In the head 1 of the sewing machine a supporting socket 2 for the stepper foot 4 is mounted, which accommodates the shaft 3 of the stepper foot 4. In an additional socket 5 secured in head 1, the needle bar 6 is mounted on which the needle holder 9, which carries the needle 7 with the needle eye 8, is threadedly secured. A lug 10 with a downwardly projecting thread guide eyelet I1 is connected to the upper portion of the needle holder 9.

A holder 12 is clamped onto the stepper foot socket 2 which carries a frame 13. The frame 13 has a center part or crossbar 14 which extends transversely of the path of movement of needle 7 and is disposed between the path of the thread eye 11 and path of the needle 7 at such a height, that in the lower position of needle shaft 6 it is overlapped by the thread guide eyelet l I as shown by the dashed lines in the drawing.

As a result of this arrangement, the direction of the needle thread 15 is changed by the crossbar 14 immediately before the entrance of the looper point, which is not illustrated, into the sling forming a loop at the needle eye 8 above the stitch plate 16 of the machine, so that the surplus length of the sewing thread 15 disposed between the thread lever, (not illustrated) and the needle eye 8 is caught and only the loop formation is effected of the size required for the entrance of the looper point.

In the threading position of needle 7, shown in the drawing in solid lines, the needle eye 8 is located above the center part I4 of the frame I3, so that the needle thread 15 coming from the thread lever of the machine is threaded into needle eye 8 after having been threaded through the thread guide eyelet I I.

The frame 13 is equipped with two finger guards I7, which extend downwardly and forwardly from the side portions of frame I3. These finger guards I7 are intended to prevent the fingers of the operator guiding the forward-moving material being sewn from being drawn into the path of the needle 7.

Having now described my invention with reference to the embodiment illustrated in the drawings, I do not wish to be limited thereto, but what I desire to protect by letters patent of the United States is set forth in the appended claims.

I claim:

1. Device for guiding the needle thread of a sewing machine having a housing and a needle bar supporting a needle having an eyelet, an outwardly and downwardly extending L-shaped member supported by said needle bar, said downwardly extending portion terminating in a free end, a thread guide eyelet in said free end, a frame fixed to said housing and extending downwardly therefrom, a transverse bar disposed at the lower end of .said frame proximate the lowest point of movement of said thread guide eyelet between said needle bar and said free end of said L-shaped member, whereby for the lowest position of said needle bar the thread between said thread guide eyelet and the needle eyelet is disposed over said transverse bar thus assisting in tensioning and guiding of the thread during formation of the stitch loop.

2. Device in accordance with claim I, where said frame is disposed in front of the path of movement of said needle and finger guards extend from the lower end of said frame.

Claims

1. Device for guiding the needle thread of a sewing machine having a housing and a needle bar supporting a needle having an eyelet, an outwardly and downwardly extending L-shaped member supported by said needle bar, said downwardly extending portion terminating in a free end, a thread guide eyelet in said free end, a frame fixed to said housing and extending downwardly therefrom, a transverse bar disposed at the lower end of said frame proximate the lowest point of movement of said thread guide eyelet between said needle bar and said free end of said L-shaped member, whereby for the lowest position of said needle bar the thread between said thread guide eyelet and the needle eyelet is disposed over said transverse bar thus assisting in tensioning and guiding of the thread during formation of the stitch loop.

2. Device in accordance with claim 1, where said frame is disposed in front of the path of movement of said needle and finger guards extend from the lower end of said frame.