US2544577A

US2544577A - Needle-threading mechanism for sewing machines

Info

Publication number: US2544577A
Application number: US53008A
Authority: US
Inventors: Max E Weber
Original assignee: Singer Co
Current assignee: Singer Co
Priority date: 1948-10-06
Filing date: 1948-10-06
Publication date: 1951-03-06
Anticipated expiration: 1968-03-06

Description

M. E. WEBER March 6, 1951 NEEDLE-THREADING MECHANISM FOR SEWING MACHINES 2 Sheets-Sheet 1 Filed Oct.

lnfi` @mam/tov Wax E. ZUeer M. E. WEBER March 6, 1951 NEEDLE-THREADING MECHANISM FOR SEWING MACHINES 2 Sheets-Sheet 2 Filed Oct. 6, 1948 m W w m w w ww m Wax E. 2066er Patented Mar. 6, 1951 NEEDLE-THREADING MECHANISM FOR SEWING MACHINES Max E. Weber, Brooklyn, N. Y., assignor to The Singer Manufacturing N. J., a corporation of New Jersey Application October 6, 1948, Serial No. 53,008

This invention relates to needle-threading devices for use with sewing machines, and more specically to a needle-threading device which may be incorporated in the sewing machine as an integrated component thereof.

It is an object of the invention to provide a means whereby the needle of a sewing machine may be threaded without requiring the operator to manually seek out the needle-eye in the usual manner of threading needles. Accordingly this invention includes a retractable carrier for a needle-threading element which is controlled by simple hand operations and which automatically projects a thread-receiving portion of the threading element through the eye of the needle. Once the threading element is projected through the needle-eye itybecomes a relatively simple procedure to thread the needle by engaging the thread therewith and withdrawing the threading element from the needle eye.

Another object of the invention is to provide means whereby the threading device is self-adjusting to accommodate variations in the position of the needle above the throat-plate oi the sewing machine. Thus, the needle-eye need not be disposed at any specific or predetermined height in order for the device to be operable, but rather may be positioned anywhere within a given range.

A further object of the invention is to incorporate this self-aligning needle-threading mechanism within the frame of the sewing machine. In the embodiment of the invention selected for illustration, the face-plate has been adapted to house the mechanism, as shown in the accompanying gures in which:

Fig. 1 is a vertical sectional view of the headend of a sewing machine bracket-arm to which has been affixed a face-plate incorporating the needle-threading device, the needle-threading mechanism being shown in its retracted or inoperative position. Y Y

Fig. 2 is a partial duplication of Fig. 1, with the major portion of the needle-threading mechanism shown in elevation and showing, in full and dotted lines, the threading mechanism in two successive stages of operation.

Fig. 3 is a front elevational view of the faceplate carrying the needle-threader, a portion of the needle-bar and needle also being shown.

Fig. 4 is a rear elevational view of the faceplate and the needle-threading mechanism car- Tied thereby.

Fig. 5 is a vertical sectional view taken substantially along the line 5-5 of Fig. 4, lbut showing the threading device shifted to its operative Claims. (Cl. 112-225) Company, Elizabeth,

2 position and the threading element projected through the needle eye. K

Fig. 6 is a perspective view of three component elements of the device.

Fig. 7 is an enlarged horizontal sectional view taken substantially on the line 'I-I of Fig. 1.

Fig. 8 is an enlarged horizontal sectional view taken substantially on the line 8-8 of Fig. 1.

Fig. 9 is an enlarged sectional view, taken substantially on the line 9-9 of Fig. 2. The portion of a sewing machine shown includes part of a bracket-arm I having a hollow head 2 disposed at its free end. The head supports a reciprocatory needle-bar 3 carrying a needle 4 at its lower end. The needle is of the conventional sewing machine type, being provided with a thread-eye 5 proximate to its point. The needle-bar is reciprocated by a rotary armshaft E through a conventional crank 'I and connecting link 8. A presser-bar 9 is slidably mounted in the head 2 rearwardly of the needle'- bar and has a presser-foot I0 secured to its lower end.

The hollow head 2 is closed by a face-plate II secured to the head by a screw I2. The faceplate carries the present improved needlethreading mechanism, the preferred embodiment of which comprises a threading element, preferably but not necessarily in the form of a hook I3 secured to the lower free end of a carrier-arm I4 having bodily endwise and swinging movements. The hook I3 is designed to have its free end projected through the eye of the needle and to have the needle f thread placed therein, after which thehook is withdrawn from the needleeye pulling the thread with it, thereby threading the needle. Below the hook I3 the carrier arm or a separate head 45 carried thereby is bifurcated, as indicated at Illa, to straddle the needle thereby to facilitate passage of the hook I3 through the thread-eye 5. The carrier-arm I4 is mounted for vertical endwise movements in'a slideway provided in the face-plate. This slideway is defined by a pair of parallel vertical walls I5 and IE, the former being provided by a thickened portion IIa of the face-plate and the latter being provided by a separate angular guide member I'I held to the face-plate by a pair of screw I'I' (see Figs. 4 and 8). Y

The carrier I 4 is provided at its upper end with an enlarged portion from which project a pair of vertically spaced guiding pins, or studs, I8 and I9. A vertical guide slot 2l) `is cut in the wall I6 of the guide member I'I and receives the pins I8 and I9 of the carrier.

The pins fit snugly within the major portion of the slot 2li thereby restricting the carrier to movements in a vertical line. The slot 20, however, is provided with a widened portion 2I, which when entered by the guiding pins I8 and I9 permits limited angular movement of the carrier I4 (Fig. 5). This angular fmovement is yieldingly opposed ,by a two-armed lever 22 (Fig. 4) which is pivoted to a lug IIb on the inner surface of the faceplate by means of a shoulder screw 23. The lower arm of the lever 22 is .biasedagainst .the carrier I4 by a coil spring 24 interposed'between the upper arm of the lever and the inner surface of the face-plate.

To facilitate endwise and swinging movements of the carrier I4 a manual control device Yis provided comprising a slide-block 25 secured 'by .a pin 25a to an ear 26 on the carrier arm I4, which ear projects through the slideway in the Yfaceplate defined by the walls I5 and I6, and a ringer ipiece' .2,1 pivotally secured to fthe slide-block. The nger piece 21 may berswung tofits inoperativeqpositionas -shown in full lines in Fig. l, or to its operative position asshownin dotted lines. 712er-,pressing downwardly on -the'nger piece (it rst having'rbeenswung to yits 'horizontal or Yop- Yerativeposition) the carrier I4 is caused to be loweredvertically until'the guiding pins LS and .L9 renter vthe -widened portion -2I of `the guide slot 29, after which, vunder Ycontinued pressure .onthefingerpiece the'carrieris caused to pivot about the Apin I8 Van amount governed by the .breadth-.of :widened portion '.2I of the slot y2i). .This-pivotal movement of the carrier -is `utilized to project-the :hooked `end portion of the mem- .ber I3 through the needle-eyegpreparatory to-.the needle-threading operation.

In the absence of a suitable 'control means it would-be necessary to manually align 'the needle- .eye-and the threading hook-each time :the device .were used. This invention, however, `overcomes .that'necessity by providingmeansfor automatically aligning the threading hook with theneedleteye-in-anyone o'f1a .plurality of positions within aconsiderable range of movement of the needlebar. This'means comprises an element 23v slidingly .mounted lon the guide member .I-1 and Vadaptedzto connect theneedle-bar 3 andthe car- ;rier I4, :using the needle-bar as a lgauge from "which toiposition' the ithreading hook relative Yto .:th.e1needleeye. In other words the Jposition of the :needle-paris utilized to determine Vthe operative `position of Athe carrier by means :of the interposedv sliding element 2.8.

'The sliding element 28 yis formed-at its upper .and lower .ends with angle-portions 29 and .33

,havingidownturned and

upturned lingers

31 and 36, respectively,hereinafter mentioned. A notch 3.I isucut in thelower part ofthe verticaledge vof the stationary yguide member I1 to accommodate-the :angle-portion of the sliding element 28 :andito define thelimits of the Asliding move- 'ment-of `that element. A screw v32 is threaded -into the stationary element I1 4and'has lan enlarged head 4portion which overhangs an -edge -0f the sliding element'ZB to hold the 'latter in contact -with the guide member I1. Secured to the/element 23, intermediate its ends, is a U- shaped bracket 4I affording a pair of spaced par- 'all'el

arms

33 and 34 which extend voutwardly Vfrom the sliding element. The arms straddle Itheneedle-bar 3 above a collar 35 on the needle- A'bar lto which 'the driving link y8 is voperatively connected.

upturned linger 35 =on --thelowerend fof the element 28 slides in the lower portion of the slot 20 in stationary element I1 (see dotted lines, Fig. 6). The tip of this nger 36 forms a bearing or pivot point against which the pin I8 of the carrier arm I4 bears when the device is in use (Fig. 5).

The .tip ,of 'the downturned nger V31 on the upper end of the sliding element '23 is engaged by a horizontal shoulder 38 on the carrier arm I'4 (Fig. l) as the device is moved to its upper .or inoperative position. In this inoperative position,'the sliding element 28 is held in its uppermost position by the shoulder 38 and consequentlythe pair of

arms

33 and 34 of the element :28, are :maintained above and beyond the Stroke or pathfof travel of the collar 35 on the reciprocatory needle-bar 3. The carrier arm I4 is frictionally maintained in this inoperative position by a spring detent 39 secured to the inside face of the face-plate II and which has a .rounded-.portion.releasablyentering a notch 40 .fin `the carrier arm I4.

To operate the present needle-threader the vcarrier AI4 is Vslid downwardly, to aboutthe position illustrated Iin Figs. 2 and 5, by means'of its finger piece 21. In moving downwardly, the shouder 380i the carrier I4'moves away from the lower endofthe'finger 31^of the sliding element T28 until the pin I8 of the -carrier engages the :upstanding nger 36. Thereafter lthe element .28- -moves ydownwarcllywith the carrier I4 until the .

arms

33 and 34 engage the collar 35 on the needle-bar (Fig. .2).

vWitharms 33 and 34'bearing upon thecollar .35 of the needle-bar 3, the sliding elementZil .is festablished in a fixed poition relative to the needle-bar. Furthermore, the pin I8 of the carrier I4-in bearing-upon the finger 36 ofthe sliding element'28, causes the carrier to assume `a fixed vertical position relatively to the needlebarand yto the needle carried thereby. Within .a xed range of positions vof the needle-'bar these elements .are able to .assume -the same relative positions. 'ITh-ethreading hook lf3 thusbeing established at the proper height with respect tto itheneedle-eye '5, .it remains only 'to swing'the .carrier inwardly'to pass the threadinghcok'into andthrough the eye ofthe needle. This .is accomplished Aby continuing to press downwardly on the nger-piece `21 of the carrier which sets up a turning moment about the pivot pin I8.

'The pin IQ-at this point is disposed within the enlarged portion 2| of the guiding slot 20 and thus there is permitted limited angular movement of the carrier I4 (Fig. 5) suiiicient to allow the rthreading-hook to be -swung into the eye -ofthe needle against the laction of the springbiased lever 22.

Once the-thread has been ensnared on the hook vI3 the finger piece 21 may be released, permitting the spring-biased lever 22 to return the carrier to its vertical position carrying with it the thread- 'ing hook which vdraws a bight of the thread through the eye of the needle. The thread may then be lifted from the hook and the carrier raised to its inoperative position.

It may -tnus be seen that the operation of this `mechanism is independent of the relative position ofthe `needle with respect to the sewing machine frame within pre-established limits of substantial amplitude. The needle-bar may be disposed in any position between the top of itsstroke Nand Aa-point well beneathr the top which is govlerned in thev illustrated `mechanism by the engagement of the angle vportion 3Uofthe element 28 with the lower edge of the notch 3| in the member I1.

It is possible to make adjustments in the mechanism for accommodating, for example, needles of different lengths or in which the eye of the needle is disposed a different distance from the iiXed collar 35 on the needle-bar. To accomplish this purpose the unitary U-shaped bracket 4I (Figs. 6 and 7) is provided with an elongated slot d2 (Figs. 1 and 4) entered by a clamp screw d3 which secures the bracket to the sliding element 28. By shifting the bracket, within the limits defined by the slot d2, the ultimate position assumed by the threading-hook I3 relative to the needle-eye may be varied.

To facilitate removal and replacement of the threading hook I3, should that element become broken, the hook i5 preferably secured, by a screw 44, in a head 45 removably secured by a clamp screw 46 tothe lower end of the carrier-arm le. The arm I4 is provided with a transverse rib il adapted to t within a slideway 48 formed in the head 45. Thus by loosening the screw 26 the head 45, and the hook I3 carried thereby, may be entirely removed from the carrier-arm for ready removal and replacement of the hook I3.

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

l. In a sewing machine provided with a reciprocating needle having a thread-eye; a needle threader carried by the sewing machine and comprising a carrier-arm, a threading element carried by said carrier-arm, means to shift said carrier-arm and threading element lengthwise of said needle to align said `threading element with said thread-eye in any one of a plurality of vertical positions of said needle, means to swing said carrier-arm and threading element to a position in which a portion of the threading element is projected through said thread-eye to receive therein a thread, and means to retracty said carrier-arm and threading element to draw a portion of said thread through said thread-eye.

2. In a sewing machine provided with a faceplate and a reciprocating needle having a threadeye; a needle threader carried by said face-plate and comprising a carrier-arm mounted in said face-plate for bodily endwise and swinging movements, a threading element carried by said carrier-arm, means to shift said carrier-arm and threading element lengthwise of said needle to align said threading element with said threadeye, means to swing said carrier-arm and threading element to a position in which a portion of the threading element is projected through said thread-eye to receive therein a thread, and spring means to retract said carrier-arm and threading element to draw a portion of said thread through said thread-eye.

3. In a sewing machine provided with a faceplate and a reciprocating needle having a threadeye; a needle threader carried by said face-plate and comprising a carrier-arm, a threading element carried by said carrier-arm, a guide member carried by said face-plate and provided with a vertically disposed guide slot, means on said carrier-arm tracking said guide slot, means to shift said carrier-arm and threading element lengthwise of said needle to align said threading element with said thread-eye, means to swing said carrier-arm and threading element to a position in which a portion of the threading element is projected through said thread-eye to receive therein a thread, and spring means to retract said carrier-arm and threading element to B draw a bight of said thread through said threadeye.

4. In a sewing machine provided with a faceplate and a reciprocating needle having a threadeye; a needle threader carried by said face-plate and comprising a carrier-arm, a threading element carried by said carrier-arm, a guide member carried by said face-plate and provided with a vertically disposed guide slot having a widened portion, a pair of spaced studs on said carrierarm tracking said guide slot, means to shift said carrier-arm and threading element lengthwise of said needle to align said threading element with said thread-eye in any one of a plurality of vertical positions of said needle, means operable when one of said studs is in the widened portion of Said guide slot to swing said carrier-arm and threading element to a position in which a portion of the threading element is projected through said thread-eye to receive therein a thread, and spring means to retract said carrier-arm and threading element to draw a bight of said thread through said thread-eye.

5. In a sewing machine provided with a faceplate and a reciprocating needle having a threadeye; a needle threader carried by said face-plate and comprising a carrier-arm, a spring detent acting on said carrier-arm to yieldingly retain it in inoperative position, a threading element carried by said carrier-arm, a guide member carried by said face-plate and provided with a Vertically disposed guide slot having a widened portion, a pair of spaced studs on said carrier-arm tracking said guide slot, a nger piece attached to the carrier-arm to shift the carrier-arm and threading element lengthwise of said needle to align said threading element with said threadeye in any one of a plurality of vertical positions of said needle and when one of said studs is in the widened portion of said guide slot to swing said carrier-arm and threading element to a position in which a portion of the threading element is projected through said thread-eye to receive therein a thread, and spring ,means to retract said carrier-arm and threading element to draw a bight of said thread through said thread-eye.

6. In a sewing machine provided with a faceplate, a reciprocating needle-bar, a needle carried by the needle-bar and having a thread-eye; a needle threader carried by the face-plate and comprising a carrier-arm, a threading member carried by said carrier-arm, means to shift said carrier-arm and threading member lengthwise of said needle-bar, an element slidingly mounted on said face-plate and movable vertically with said needle-bar throughout a portion of its stroke and having a denite position relative to the eye ci the needle, cooperating stop means provided by said carrier-arm and said element to cause the arm and the element to be moved together during that portion of the stroke of the needlebar when the element moves therewith and to position said threading member in alignment with said thread-eye, means to swing said carrier-arm and threading member to a position in which a portion of the threading member is projected through said thread-eye to receive therein a thread, and spring means to retract said carrier-arm and threading member to draw a portion of said thread through said thread-eye.

7. In a sewing machine provided with a faceplate, a reciprocating needle-bar, and a needle carried by the needle-bar and having a threadeye; a needle threader carried by said face-plate andnormally disconnected .ffrorn said needle-bar and needle, said needle threader comprising a carrier-arm, athreadingelement'carried by said carrier-arm', 'detent means Ato `'hold said carrierarm Aand threading element iin an inoperative position, means to 'shift said carrier-arm and `threading elementflengthwise of said needle-bar to-align said threading `element with said threadeye -inanyrone of a plurality Tof vertical positions of said needle, -means to swing said carrier-arm and threading element to project a portion of the threading element through lsaid thread-eye to vreceive therein a thread, and means acting on said carrier-armltofretract `the carrier-arm and threading element to fdraw the thread through said thread-eye.

8. 4In a sewing machine provided with a'faceplate, a reciprocating needle-bar, a needle carried thereby andh'aving a thread-eye, and means fior reciprocating said needle-bar; a needle threader carried by said face-plate and comprising-a carrier-arm mounted on said face-plate for bodily endwise and swinging movements, a threading member carried by said carrier-arm, means to shift said carrier-arm and threading member lengthwise of said needle-bar, an element slidably mounted on said face-plate, an arm'carried by said element and engaging a portion of the needle-bar reciprocating means for causing said element to be moved vertically with said needle-bar during a portion of its stroke and to have a-predetermined position relative to 'the 'eye of the needle, cooperating stop means provided by said carrier-arm and said element to causethe 'arm and 'the element to be moved together'during that portion of the stroke of the needle-bar when the 'element is moved therewith and to position said threading member in alignment with said thread-eye, means to swing said carrier-arm and threading member to project a portion of the member through the thread-eye to receive therein a thread, and means to retract 'the carrier-arm and threading member to draw 8 a 'portion offsaid thread through-saidthread-eye.

9. A needle threader for sewing machines as set forth in claim 8, in which the arm, which is carried by the element'slidingly mounted on the face-plate and which engages a portion of the needle-bar reciprocating means, is vertically adjustable to adapt the'needle threader for needles of different lengths.

10. In a sewing machine provided with a faceplate, a reciprocating needle-bar, and a needle carried by said needle-bar and having a threadeye; a needle threader carried by said face-plate and comprising a carrier-arm mounted in said face-plate for bodily moving in a straight line and for swinging movements about an axis transverse to saidstraight line, a threading element carried by said carrier-arm, means for guiding said carrier-arm endwise of itself and in said straight line throughout one end portion of its amplitude of straight line travel, means providing a transverse aXis pivot about which said carrier-arm may be swung whenever said carrier-arm is shifted to the other end portion of its amplitude of straightline travel so that said threading elementmay be projected through said thread-eye, and means for connecting said pivot means with said needle-bar thereby accurately to position said threading element relative to the needle-eye preparatory to the swinging of said carrier-arm about said pivot means.

MAX E. WEBER.

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

UNITED STATES 'PATENTS Number Name Date 258,345 Altmann et al May 23, 1882- 258,870 Altmann et al June 6, 1882 479,426 Jenkins July 26, 1892 2,108,474 Brun et al Feb. 15, 1938