US3291084A - Needle eye threading device - Google Patents

Description

1966 YOSHIHIKO ASAHATA 3,291,084

NEEDLE EYE THREADING DEVICE Filed April 1, 1964 FIG.

FIG.

FIG. 3

I NVEN TOR.

BY M- United States Patent i 3,291,084 NEEDLE EYE THREADING DEVICE Yoshihiko Asahata, 151 Z-chome Shimoshinjo-maelii, Higashiyodogawa-ku, OSaka shi, Japan Filed Apr. 1, 1964, Ser. No. 356,423 1 Claim. (Cl. 112225) This invention relates to a new and improved device capable of easily passing thread through the eyes of needles such as sewing needles and embroidering needles used in the production of sewn products and embroidered products.

Heretofore, such needle threading operation has, in almost all cases, been carried out by hand. Such practice is inefiicient and requires experience and skill, a high degree of skill being required particularly in cases where a large number of needles are required to be operated at one time as, for example, in an embroidery lace machine.

It is an object of the present invention to overcome this deficiency by providing a device of relative simple construction capable of easily and rapidly threading the eyes of needles.

It is another object of the invention to provide a device of the above stated character which can be operated by a large number of operators who are not highly skilled.

It is a further object to provide a device of the above stated character which is capable of rapidly threading a large number of needles.

It is a still further object to provide a device of the above stated character which is adaptable to and contributive to automatization of needle threading work.

With the foregoing objects and other specific objects in view, the invention resides in the novel arrangement and combination of parts and in the details of construction hereinafter described and claimed, reference being had to the accompanying drawings in which like parts are designated by like reference characters, and in which:

FIGURE 1 is an elevational view, with a part cut away, showing the embodiment of the needle threader according to the invention;

FIGURE 2 is a sectional view of the section taken along the plane indicated by line II-II in FIGURE 1;

FIGURE 3 is a sectional view of the section taken along the plane indicated by line IIIIII in FIGURE 1; and

FIGURE 4 is a sectional view of the section taken along the plane indicated by line IVIV in FIGURE 1.

Referring to the drawings, the support structure of the embodiment of the invention shown consists essentially of a base plate 1, a cover plate 2 disposed parallelly and secured by a screw 4 to the base plate 1 with a suitable gap therebetween, and a bar 3 which is directed in a direction parallel to a support member (not shown), and to which bar 3 the root part of the cover plate 2 is perpendicularly fixed. The bar 3 is so supported that it is capable of rotating about its axis and, moreover, of moving to the left and right as viewed in FIGURES 1 and 2. The rotational and left and right movements of this bar 3 may be effected automatically by mechanical power means (not shown) or manually.

In the gap between the base plate 1 and the cover plate 2, there is provided a guide lever 7 having a hook part 6 at its free end and pivoted at its other end on a pin supported on the base plate 1 and cover plate 2. This guide lever 7 is made to have a thickness such that it can freely pass through the eye 14 of a sewing needle (or embroidery needle) a placed in the needle threading device.

The outer end (that is, the right-hand end as viewed in FIGURES l and 2) of the base plate 1 is provided with a bent back part 8 curved toward the side of the cover plate 2 and then back toward the fixed end of the cover plate 2. A gap is provided between the extreme end of the easiest Patented Dec. 13, 1966 cover plate 2 and the extreme end of this bent back part 8 so as to permit the passing therethrough of a needle with suflicient clearance. Stepped cutouts 2 and 1 are provided respectively at the outer end of the base plate 2 and the part of the base plate 1 confronting said outer end, said stepped cutouts 2 and 1 being in mutually facing and symmetrical disposition so as to form a groove for accommodating a needle to be threaded as will be described hereinafter. At approximately central parts of the bent back part 8 and the end part of the base plate 1 facing the bent back part 8, there are formed respective threading slots 9, 9 of converging shape extending upwardly at an inclined angle from the outer edge of the said parts as shown most clearly in FIGURE 1. The inner ends of these threading slots 9, 9 communicate with respective thread receiving holes 10, 10 formed in the base plate 1 and bent back plate 8 at positions within the radius of rotation of the afore-mentioned hook part 6 of the guide lever 7.

A stop 11 is fixed to the base plate 1 so as to limit the rotational range of the guide lever 7 in the clockwise direction as viewed in FIGURE 1. A spring 12 is provided to impart a moment to the guide lever 7 always urging it to rotate in the clockwise direction as viewed in FIGURE 1, and this rotational tendency can be locked by a latch member 13. .This latch member 13 is supported on the base plate 1 in a manner permitting it to be projected out and retracted at a relative position such that, at the time of retraction of the needle a, as will be described more fully hereinafter, when the guide lever 7 caused to rotate by actuation due to the eye 14 disengages from the eye 14 of this retracting needle a, the latch member 13 locks the guide lever 7, which is normally in this locked state when not in use. Reference characters 14,, and 14 designate depressions generally formed on the left and right sides of the eye 14 of the needle a.

The needle threading device of the invention of the above described construction operates in the following manner. When a thread passed through a needle a breaks because of some cause, this thread break can be readily detected in both the case of a sewing machine and the case of an embroidery lace machine (in which latter case an automatic monitoring and indicating means such as buzzer or a blinker lamp is usually provided).

When, in such a machine provided with the needle threading device of this invention mounted in a suitable position therein, a thread break is detected, the latch member 13 is retracted (downwardly as viewed in FIGURE 2) by a manually operated mechanism or by any suitable means such as an electromagnetic device (not shown) activated by an automatic monitoring and indicating system. Consequently, the guide lever which has been locked by the latch member 13 is released and is caused by the spring 12 to rotate in the clockwise direction (as viewed in FIGURE 1) until it is stopped by the stop 11.

When the needle threader in the above described state is rotated by the rotation of the bar 3 to the side of the needle a, the extreme end of the bent back part 8 of the base plate 1 and the extreme end of the cover plate 2 pass by opposite sides of the needle a with sufiicient clearance, whereby, in relative effect, the needle a enters through the gap between the two said extreme ends. Then the needle threader is shifted together with the bar 3 to the right as viewed in FIGURES 1 and 2, whereupon the needle a is encompassed on three sides by the aforementioned groove formed by the stepped cutouts 1 and 2,, 'formed in the base plate 1 and the cover plate 2. Accordingly, if the needle a is advanced beforehand to the appropriate position, the hook part 6 of the guide lever '7 will fit into the eye 14 of the needle a. This state of the operation is shown in FIGURE 1.

On one hand, a thread end b drawn out from a bobbin (not shown) is introduced at a suitable time after the above described operational step or prior thereto through the threading slots 9, 9 on the base plate 1 into the thread receiving holes 10, 10, a thread end of suitable surplus length being left.

Then when, with the needle threader, needle, and thread in the above described state, the needle a is retracted, the guide lever 7 is actuated accordingly by the eye 14 of the needle a to rotate in the counter-clockwise direction (as viewed in FIGURE 1) against the elastic force of the spring 12. As the retraction of the needle a proceeds and reaches approximately the midpoint of its stroke, the hook part 6 of the guide lever 7 passes through the eye 14 to the opposite side. Then, as the retraction of the needle a proceeds further, the resulting rotation of the guide lever 7 causes the hook part 6 to hook the thread b at its span between the thread receiving holes 10, 10. Still further retraction of the needle a causes further rotation of the guide lever 7 whereby the hook part 6, still with the thread b hooked therein, is caused to begin withdrawal from the eye 14, and the guide lever 7 overrides the latch member 13 and is locked thereby.

The working end of the latch member 13 is preferably provided with an inclined surface as indicated in FIG- URE 2 so as to facilitate the passing of the guide lever 7 thereover. At this point in the operation when the guide lever 7 is locked by the latch member 13, the hook part 6 of the lever 7 is in the state of being almost completely withdrawn from the eye 14 as indicated by the two-dot chain line in FIGURE 1, and the thread end b from the bobbin is in a state of being passed almost completely through the eye 14.

Then, after the needle threader has been shifted to the left as viewed in FIGURES 1 and 2, the needle a is caused to advance. Consequently, and since the guide lever 7 is locked by the latch member 13, the thread b, which, having been hooked by the hook part 6 at the tip of the guide lever 7, is stretched between the hook part 6 and the thread receiving holes 10, 10, is further stretched as the needle a advances, whereby the thread part on the bobbin side from the hook part 6 is pressed by the eye 14 and is drawn out from the bobbin. At this time, the thread part from the hook part 6 to the extreme end of the thread becomes progressively shorter as the needle a advances and would finally slip off the hook part 6 if it were short. However, if this thread end is provided with a sufiicient surplus length as mentioned hereinbefore, it will not pass out, unthreaded, from the eye 14 toward the bobbin side.

On the other hand, the thread part extending from the hook part 6 by way of the thread receiving hole to the bobbin slips out of the threading slot 9 during the latter part of the advance of the needle a because of the inclination of the threading slot 9.

The entrance parts of this threading slot 9 and the end part of the needle threader assembly contiguous thereto are preferably formed to have rounded, fair contours as indicated in FIGURE 1 so as to facilitate the smooth separation of the thread from the threading slot 9.

The needle threading operation is thus completed, and the sewing (or embroidering) operation can be resumed. If necessary, the needle threader assembly may be adapted to rotate together with the bar 3 to be amply separated from the neede a for resumption of sewing (or embroidering).

From the foregoing disclosure, it will be seen that the present invention provides a needle threading device by the use of which thread can be passed through the eyes of needles by any number of operators without high skill, whereby Work efficiency can be greatly increased. Moreover, the needle threading device of the invention is adaptable to and contributive to automatization of needle threading steps and is particularly suitable and useful for application to machines such as embroidery lace machines wherein a large number of needles are operated at the same time.

It should be understood, of course, that the foregoing disclosure relates to only a preferred embodiment of the invention and that it is intended to cover all changes and modifications of the example of the invention herein chosen for the purposes of the disclosure, which do not constitute departures from the spirit and scope of the invention as set forth in the appended claim.

What I claim is:

A device for passing thread through the eye of a needle, comprising in combination,

(a) a base plate having a bent back part provided with threading slots for holding thread and a cover plate disposed parallel and secured to said base plate with a suitable gap therebetween, confronting ends of said bent back part and cover plate being spaced apart so as to insert a needle to be threaded therethrough, said base and cover plates defining a guide groove to hold said needle therein towards the outer end of said cover plate and part of the base plate confronting said cover plate outer end;

(b) a guide lever including a hook portion pivotally supported in said gap between said plates, said hook portion being positioned to freely pass through the eye of a needle located in said guide groove, said guide lever being adapted to be rotated by said needle eye when the needle undergoes longitudinal movement, the length of the lever being selected so as to be rotated by said needle movement and passed first through the needle eye from one side of the needle to the other side thereof, and, as its rotation progresses, passed between said threading slots on the other side so as to hook onto thread therein, and back through said eye to said one side by further rotation of said guide lever thereby drawing and passing said thread through the needle eye;

(c) a latch member, supported on said base plate so as to project out and retract to lock said guide lever when the device is not used; and,

(d) a stop fixed to the base plate to limit the rotational range of the guide lever.

References Cited by the Examiner UNITED STATES PATENTS 2,490,882 12/1949 Pinkham et al. 223-99 2,518,287 8/1950 Costello 22399 2,543,587 2/1951 Nas 223-99 2,552,731 5/1951 Pinkham et al. 112225 JORDAN FRANKLIN, Primary Examiner.

RICHARD J. SCANLAN, .TR., Examiner. I

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