US2506275A - Needle threading device - Google Patents

Description

May 2, 1950 J. H. OLDHAM NEEDLE THREADING DEVICE 2E She ets-Sheet 1 Filed 001;. 20, 1947 INVEN TOR. Jaw l7! OLflH/IM,

A TT'ORNE).

y 2, 195a .J. H; OLDHAM 2,506,275

NEEDLE THREADINGDEVICE Filed Oct. 20. 1947 2 Sheets-Sheet 2 Hill-UM g INVENTOR. 30 28 JOHN h. 0L DH/IM,

v BY 9 Patented May 2, 1950 TENT OFFICE NEEDLE THREADING DEVICE John H. Oldham, Fort Lauderd'a le, the.

Application October 20, 1947; Serial No; 780,839

5 Claims. 1

This invention relates to improvements in needle threading devices, particularly sewing machine needles.

It is an object of the present invention to provide a threading device that may be quickly and accurately positioned relative to a sewing machine needle to facilitate the passage of the thread through the needle eye.

A further object of the invention resides in the provision of a threading device that may be quickly positioned with respect to a sewing machine needle to be clamped in accurate position relative to the needle eye between the conventional needle bar and pressure foot of the machine and, so constructed that, upon completion of the needle threading and the subsequent release of pressure by the needle bar, the device will bodily fall away from the needle and associated parts, simultaneously disengaging itself from the thread.

Another and highly important object of the invention resides in the ability of the threadr to automatically adjust itself to needles of varying: sizes for exact alignment and positioning of the device with respect to the needle eye whereby the thread guide will at all times be automatically in axial alignment with the eye of the needle.

A further object resides in the extreme sir'n' plicity of the device; requiring no adjustments or skin in its operation, is siniple iii onstruction. is strong, durable,- cheap to manufacture and highly efii'cient usea Other important objects" and advantages of the inventionwill readily present" themselves during the course of the following description, reference being had to the accompanying drawings, wherein:

Figure 1 is a fragmentary erspective View T a sewing machine needle barand pressure foot, showing the invention use,

Figure 2 is a slightly eh'lar'gedsid" elevation Of the device aspo'siti'oned upon the sewing machine and in the act of directing the thread through tli'eneedle eye,

Figure 3is'a: top plan view of the threade'r';

Figure 4 is a vertical section; taken on" line l -J of Figure 3, I

Figure 5 is an enlarged front elevation-ofthe threader',

Figure 6 is" a" horizontal: section taken on" line 66' of Figure"4-,-

Figure '7 isa" cross section" taken on' line L4" of Figure 6,

Figure: 8 is a greatly magnified aegis-emer the thread guide, illustrating the relative posi tions of the needle eyes of variable sized needles,

Figure 9 is a view similar to Figure 8, but illustrating a slightly modified needle positioning channel,

Figure 10 is an enlarged side elevation of a modified form of threader;

Figure 11 is a front edge view thereof,

Figure 12 is a vertical section on line I Z I 2 or Figure 11 and,

Figure 13 is a top plan view of the device.

Like numerals are employed to designatelike parts throughout the severalfigures of the draw 1ngs.-

Referring specifically to the drawings and par ticularly Figures 1 to 8 inclusive; the numeral 5 designates the body portion of the device comprising a plate 6 having its upper portion bent upon itself to'form spaced parallel side walls I, the free ends or which extend upward, as at 8; to' form engaging surfaces for the; needle bar A; The plate 6 ofis'et to provide a portion 9 for engagement with the prssiir font B or the sew: ing" machine. The terminus of" the portioii 9 is formed triangular, as" at I0, the apex or w icli seats within the nedleopening' 0 off the foot B1 in use. The onset portion of the plate 611s iii vertical eng'mfiefit withan'd centrally disposed Withr'espe'et t nsidewalls 1. iiiusethe plate is arranged upen' tiie sewinginachine with the ape of thetriarigl m engaging inthe opening 0 and rigidly clamped in such pbsition by the gagement 6f the needle barA with the extend (1 portions 3; It is feired, that the n'g'ag rig" surfaces ofthep rtions 8 be formed upon snar struck from the-ape? or; the tr'iaiig e |0, to" assur an equal clamping'pr'e'ssuieoithe device through out its rangear'ose; Y T opening C is, ineflct'; a fixed fuleruiii piii'iit for the lateral displ'a'ee ment of the de'i'iic'efirfaligiiin'g itself with tli l l. I l

Threading" r'hains-iiidicated' at H, ec'n'iipri'ses plate f2; geh'e auy rectangular in's'liap, is p v t are between the when aiidada'pted tdpartake of lateral rc' rig movement, limited by are e'r'iga-gefneritof t "points [land] 5: with the en we'll o'f thes ot ormd by'tl'i'e 'walls 1'. The 11 e1 f'ofwaid fitrefiiity'o'i the plate l2 terminates outwardly flared points l6, forming a trianguliaff socket for engagement over and centeringthe device with theflb as; or the needle- N, or the" Sh'a-Tlk' D ()f tnenedle; depending upon the degree 6f pro'triisi Of tht? Shani? D1 The points" I6 lightly eiigage-theinner surfaces of the walls I;

sectionrtakenhorizontal yrtlirough tiie exitendoi .a'l'id pellfiifi a slight-fulcrum action-sideways permit perfect alignment with the needle, there being sufficient clearance of the plate l2 over the rivet I3. The plate 12 is centrally disposed in vertical alignment with the portion 9 of the plate 6 and is ofiset at H.

The lower portion lZa of the plate I2, is bent upon itself to provide a thread channel and comprises a generally flared semi-conical portion I8, tapering forwardly to merge into a straight parallel and slightly spaced wall portion is. The wall l9 terminates in an angularly disposed, downwardly tapering lip 20, while the plate l2a. is provided with a correspondingly shaped lip 2|. The lips 20 and 2| jointly serve to provide a triangular aligning groove for the reception of the lower end of the needle and this groove is in vertical alignment with the upper triangular socket. Thus, the upper socket and lower groove jointly provide a perfect aligning means for the needle. The slot formed bythe walls I20. and it? is open at its top, while the bottom of the slot, formed by the bending of the plate provides, in conjunction with the walls [20. and Ill a definite line of travel for the end of the inserted thread. The flared portion [8 serves to facilitate the entry of'the thread to the slot for positive guiding to the eye of the needle.

As shown, the device when in position for threading, engages the shank D of the needle in the socket formed by the points l6, while the body of the needle projects downwardly and lies within the triangular groove formed by the lips 20 and 2! and, when in this position, the eye of the needle registers with the slot, with the lower end of the eye substantially in alignment with the bottom of the slot.

A horizontal cross-sectional positioning of the needle eye with respect to the slot is illustrated in Figure 8, where it will be seen that the needle eye lies in direct central alignment with the slot to receive the thread directed therethrough. The larger needle is shown by dotted lines, with the smallest needle in full lines. In the use of this form of the invention, the needle bar is raised to its uppermost limit, at which time the apex of the triangular portion l t is seated within the needle opening of the pressure foot and the device as a whole is swung inwardly toward the needle, using the portion in as the fulcrum point, at which time the threader is engaged with the shank of the needle, and being definitely centered by the engagement of the shank D in the upper triangular socket. The portions 8 at this time underlie the needle bar A. The body of the needle simultaneously centers itself in the triangular groove formed by the lips 20 and El. Movement of the needle bar downwardly will clamp the device in perfect vertically aligned engagement with the needle, with the eye of the needle in axial alignment with the lower end of the threading slot. A thread suitable to the particular needle is then inserted through the flared portion I8, riding between and guided by the bottom and side walls of the slot and emerges through the eye of the needle. The side walls and bottom of the slot tend to straighten out the end of the thread to direct its movement in a straight line toward the needle eye.

Since the threader is constructed for use with various sized needles in a given range, it follows that there must be a shifting of the carrier and threader to compensate for the various diameters of needles without distorting the needle itself. 7 As before pointed out, the opening C in the pressure foot remaining constant, serves as a fixed fulcrum point for the carrier and, as the device is placed in position against the needle, with the portion l0 engaging the pressure foot and the extensions 8 underlying the bar A, there will obviously be a slight lateral shifting of the entire device from the fulcrum point it, resulting in the axis of suspension of the threader being displaced laterally in regards to the vertical axis of the needle. This lateral displacement of the pivot point compensates progressively for the increasing distance to the bottom of the needle eye in proportion to the size of the needle. The engagement of the needle in the upper socket and lower groove causes the lower edge of the threader to move posteriorly and anteriorly and vertically depending upon the size of the needle. Vertical movement is progressively downward as the needles increase in diameter, causing the floor of the threader throat to be so adjusted that it will coincide with the needle eye.

The carrier is free to move laterally, but not posteriorly or anteriorly, describing an arc upon the fixed point of fulcrum of the pressure foot. The upper posterior or anterior movement of the carrier is restricted by the shank of the needle. Lateral movement is restricted by the pressure of the needle groove against the needle, transmitted at point of suspension of the threader and extreme lateral excursion limited to a maximum which is suflicient to cause a slight displacement of the point of the finest needle in a series from the vertical plane. Whereas this stop point would allow greater displacement of larger needles if suificient lateral pressure were applied, in practice, the additional rigidity of the larger needles do not allow this to occur when threader is brought up against the needle with the recommended slight but firm pressure. In'actual use this really gives the same action as though there was a spring holding the threader against the needle. Also, the friction of the needle bar on surface arc C is not sufficient to allow too great an engaging displacement on larger more rigid needles. Actually, the needle groove centers the threader upon the needle in respect to the needle eye, while the'carrier allows of this and maintains the threader in that position.

That portion of the plate 9 has been cut away above the triangular portion Ill and to a point slightly beyond the point of the needle as it projects below the needle groove and serves as a guard against injury to the fingers of the operator as he grasps with the thumb and finger for the projecting point of the thread as it extends through the needle eye.

As shown and described, the threader throat has been left open at its upper end and the carrier and associated parts are constructed in overbalancing relation to the fulcrum point Ill, hence, after the threading of the needle has been completed, the needle bar is elevated, which action releases the carrier and associated parts and such release permits the entire device to fall outwardly away from the needle and pressure foot and permits the thread to disengage itself from the threader by passing through the upper open end of the throat.

It should here be stated, that the thread guiding slot is of a sufficient width to accommodate the maximum sized threads for use in the maximum sized needles for which the device has been designed.

It will be seen from the foregoing that the invention so far described has been designed with ama-ximum of simplicity. It is quickly and easily attached to the machine, requiring no careful adjustments and will accurately align itself with the needle automatically with the needle eye properly positioned adjacent the bottom wall of the slot to receive the thread projected therethrough. The thread guide is so designed as to receive and straighten the thread for a perfect axial movement to the eye of the needle. In actual use, the device has been found highly satisfactory. After threading, as before pointed out, pressure release permits the dev ce to fall away from the needle and pressure foot, releas-v ing' itself from the thread, requiring no manual disengagement of the thread from theguide' In Figure 9 is illustrated a slight modification of the lower groove, in which case the lips and 2! are employed as before. However, the lips are arranged in staggered relat on-so that the apex of a triange so formed will lie off center to the thread slot and, in use, the rear edge of the needle eye of the smallest needle will be in direct alignment with the rear wall of the slot. Thus, a pointed thread travelling along the rear wall will have no opportunity to catch upon the needle outwardly of the eye. Obviously, the eye of the largest needle will substantially span the full width of the slot.

Referring now to Figures 10 to '13 inclusive, a modificat on of the complete threader is illustrated. In this form of the invention, the device may be constructed in any desirable manner, such as casting or a laminated assembly and compr ses a fixed construction with no moving parts. A fiat plate 22 serves as a body portion, offset forwardly at 23 and 24 to provide an upper head portion 25 and a lower pressure foot engaging portion 26. The head portion has its forward edge provided with a triangular, vertically arranged groove 21, the walls of which extend forwardly to terminate in straight spaced parallel walls 28. The portion 26 terminates at its lower end in a triangular foot 29, the apex of which is adapted to engage in the needle opening of the pressure foot. The parallel walls 28 are adapted to embrace the shank of the needle with their upper edges underlying the needle bar, in use.

A thread guide and needle aligning means are provided, comprising a flaring, semi-con cal mouth portion 30, tapering forwardly and merging into a straight, vertically arranged wall portion 3 I, parallel with and slightly spaced from the plate 22 for forming a thread gu ding slot 32, closed at its bottom and op n at its top. The mouth portion 30 including the wall 3|, may be formed integral with the plate 22, as by casting or it may be attached by welding or soldering. The forward edge of the plate 22 for a distance equal to the depth of the slot 32, is provided with an angular extension 33, while the free end of the wall section of the slot terminates in a correspondingly shaped angular extension 34, coextensive in length and in horizontal alignment with the extension 33, the angular extensions jointly forming a triangular slot or groove, the apex of which is centrally disposed with the slot. The groove serves to receive the lower end of the needle N. The triangular groove 35 and the groove 21 are in vertical alignment and jointly serve to correctly align the threader with respect to the needle to properly position the needle eye at the exit end of the thread slot 32. The formation of the thread guide upon the plate 22, whereby the plate 22 serves as one side wall for the slot 32, may be by casting the device as a unitary structure or it may be laminated, the thread guide preformed andattachedto the plate in any convenient manner.

In use, the device is engaged with the needle shank as before described and the foot portion swung forwardly to a position overlying-the needle opening of the pressure foot. Movement of the needle bar downwardly will obviously clamp the threader in position with the needle accurately aligned in the grooves 27 and-35 for positioning the needle eye in axial alignment with the bottom wall of the slot 32. Threading of. the needle is accomplished as before. Since this form of threader'has been designed-primarily for use on a single sized needle, it follows that it play he used on needles of-other diameters. However, the larger sized needles, due to their increased diameter both of the shank and body,- will be slightly distorted when the needle baris broughtdown to clamping position. The threading of the needle however is accomplished with a high degree of success.

It is to be understood however, that the invention is not limited to the precise arrangements shown, but that it includes within its purview, whatever changes fairly come within either the terms or the spirit of the appended claims.

Having described my invention, what I claim is:

1. A needle threading device for use in connection with a sewing machine having. a needle bar and a pressure foot, a needle carried by the bar, a threader, comprising a supporting plate having a portion thereof constructed to engage over the shank of the needle, a triangular foot portion formed on the plate for engagement with the pressure foot, extensions formed upon the shank engaging portion to be engaged by the needle bar, a thread guide supported upon the plate, needle centering and aligning means carried by the threader, said device when centered and aligned with the needle definitely positioning the needle eye in axial alignment with the thread guide.

2. A needle threading device for use upon sewing machines having a needle bar and a pressure foot, comprising a supporting plate having its upper portion bent upon itself to provide spaced parallel walls, extensions formed upon the upper free ends of the walls, a triangular offset foot portion formed upon the plate below and equidistantly spaced from the walls, an aligning and threading device pivotally supported between the walls, a trianguler socket formed upon the upper end of the threading device for engagement with the shank of a needle, the threading device provided with a thread guide having a flaring mouth portion and a restricted throat portion, triangular lip portions formed on the guide at the discharge end of the throat portion, said lips providing a triangular groove in vertical alignment with the shank socket, said guide formed open at its upper end, said socket and triangular groove serving to center and align the needle with the needle eye in axial alignment with the bottom of the throat portion.

3. A needle threading device for sewing machine supported needles comprising a supporting plate having a U-shaped head portion open at its forward end, extensions formed upon the head portion to engage beneath the needle bar of the machine, a triangular foot portion formed on the plate for engagement with the pressure foot of the machine, a needle aligning and threading plate pivotally supported in the U- shaped head to partake of lateral pivotal movemerit, a triangular socket formed upon the upper portion of the threading plate for centering engagement with the shank portion of the needle, said threading plate having its lower portion bent upon itself to provide a flaring semi-conical mouth tapering to a flat parallel wall portion slightly spaced from the threading plate to provide a restricted thread guiding throat open at its top, triangular lips formed upon the threading plate and parallel wall portion at the discharge end of the throat, said lips jointly providing a triangular groove for alignment of the needle and axial alignment of the needle eye with the bottom wall of the throat portion.

4; A threading device for sewing machine supported needles comprising a supporting plate having a U-shaped head portion and a triangular foot portion, a threader comprising a flat plate pivotally supported in the head and provided with a triangular shank engaging extension at its upper forward corner, said threader plate having its lower portion bent upon itself to provide a thread guide open at its top, said guide comprising a flaring semi-conical mouth portion tapering to a flat wall slightly spaced from and parallel with the threader plate to provide a restricted thread guiding throat, the parallel walls terminating in angularly disposed horizontally aligned lips for providing a triangular needle aligning groove, the apex of the groove being centrally arranged with respect to the throat, the shank engaging extension and the triangular groove being vertically aligned for definitely positioning the eye of the needle in axial alignment with the bottom of the thread guiding throat.

5. A threader for sewing machine supported needles comprising a body portion having a head and a lower offset triangular shaped foot portion, the forward edge of the head formed with a vertically arranged groove having parallel side walls and a triangular base, said side walls and the triangular foot adapted to be clamped in threading position between the needle bar and pressure foot respectively of a sewing machine, a thread guiding restricted throat formed on the body portion and having a semi-conical flaring mouth, a pair of angularly disposed lip portions extending forwardly from opposite sides of the discharge end of the throat for providing a needle aligning groove triangular in cross-section, the apex of which is centrally disposed with respect to the restricted throat, said triangular base and said groove serving to vertically align the threading device with respect to the needle with the eye of the needle disposed in axial alignment with the thread guiding throat, the thread guide formed upon at its top and ends.

JOHN H. OLDHAM.

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

UNITED STATES PATENTS Number Name Date 60,353 Foote Dec. 11, 1866 282,116 Pommer July 31, 1883 1,753,114 Fluharity Apr. 1, 1930

Images