US1419087A

US1419087A - Work-holding-foot mechanism

Info

Publication number: US1419087A
Authority: US
Inventors: Weis John Peter
Original assignee: METROPOLITAN SEWING MACHINE CO
Current assignee: METROPOLITAN SEWING MACHINE CO; METROPOLITAN SEWING MACHINE Corp
Priority date: 1914-10-16
Filing date: 1919-01-02
Publication date: 1922-06-06
Anticipated expiration: 1939-06-06
Also published as: US1342008A; US1419088A; US1348527A; US1352333A; US1439211A; US1450531A

Description

J. P. W EI S. WORK HOLDING FOOT MECHANISM. APPLICATION FlLED JAN. 2, 1919.

1,419,087. PatentedJune 6,1922.

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Jenn. rETEn WEIS, or NYACK, NEW YORK, ASSIGNOR or ONE-HALF 'ro mn'rnorom- TANSEWING- MACHINE CORPORATION, or novnia, DELAWARE, a oonronarron or DELAWE.

WOBK-HOLDING-FOOT MECHANISM.

Specification of Letters Patent.

Patented June e, 1922.

Original applicationfiled October 16, 1914, Serial No. 867,005. Divided and this application filed Jannary-2, 1919.- Serial No. 269,273.

To all whom alt may concern:

Be it known that I, J OHN PETER Wins, a citizen of the United States, residing at Nlyack, in the county of Rockland and State of New York, have invented certain new and useful Improvements in Work-Holding- Foot Mechanisms, of which the following is aspecification.

This invention is an improvementin w0rkholding. foot construction for sewing machines. The object of the invention is to securea simple and convenient work-holding foot which shall automatically adjustitselt to variations in thickness of goods fed to the stitch-for1ning instrumentalities while the needle is operating at high speed, and be operable to glide over the goods in a traveling sewing machine.

In the accompanying drawings forming part hereof;

Fig. 1 is a front elevational perspective ol the front end portions of the upper and under arm of a sewing machine head embodying this invention and. showing the stitch-forming instrumentalities, the workholding foot being omitted for greater clearness. I

Fig. 2 is. a front elevation of what is shown in. Fig. 1, with the work-holding foot. in place.

Fig. 3.is a perspective view of the needlebar-actuating crank removed.

Fig. l i a perspective view'of the needleholder guide detached.

Fig. 5 shows the needle holder in plan and sideelevation.

Fig. 6 is a detailed view partially in section at line 66 to Fig. 5 of the needle holder and co-operating parts.

This application is a division of my pending application Serial No. 867,005, filed October 16, 1914.

Referring to the drawings, A represents the upper arm and A the under arm of a sewing machine head. The under arm carries an oscillating looperL on a looper shait M. The upper arm carries a needle-drive shaft'D on the front end of which is a crank 1 having on its rearward side about midway between its ends a right-angular tubular socket 2 that opens through the front wall of the crank. The latter is made approximately as the segment 01 a circle and is wider at one end in order to serve as a counterbalancing weight than it is at its narrower end from thefront side of which a crank pin 3 projects. The crank socket is secured on the front end of the drive shaft D by pins 00. On crank pin 3 of this sideweighted crank there is pivoted the upper end of a dependent pitman 1 the bottom end of which is pivoted at 5 to a sliding needle holder 6 holding the shank of the needle B. In the under end portion of the upper arm A there is socketed a dependent approximately L-shaped needle-holder guide which is generally indicated by G (Fig. 4) having an approximately half-round shank 7; at the foot of the shank a laterally projecting shoulder 8 from the outer end portion oi which there projects downwardly a crosssectionally l -sha-ped bar 9 to the free edge of the flange 10 of which there is'fixed a detachable cover-plate 11 by means of screws 12. By this construction a guideway 13 is formed tor one end of the needle holder. Shank 7 is provided with a dependent cross-sectionally round needle-holder guide pin 14 that is parallel to and opposite the lengthwise opening of the guideway 13. 1

Crank 1 and crank pin 3 are formed with a lubricant duct 15 and the guide pin 14 is formed from its upper end which is flush with the upper end of the shank 7 with a lengthwise-extending lubricant duct 16 that has radial wall openings 17 serving as lubricant ducts. v

That portion of the guide G which has the lengthwise-extending guideway 13 is mounted inwardly towards the trunk T of the head, the guide pin 14' being intermediate said portion of the guide G and the needle. The needle guide has a vertical bore 18 slidahle on the guide pin 14 and an integral guide wing 19 that slides in the vertical guideway 13. Thus the needle holder is kept from. oscillation in a horizontal plane during its vertical reciprocations. At that end of the needle holder which is opposite the vertical bore 18 and guide wing 19 the needle holder is provided with a vertical bore 20 for reception of the needle shank. Between the

bores

18 and 20 the needle holder is provided with a side recess 21 so that the bore 18 and the guide wing 19 are in one fork arm and the needle-hole bore 20 in another fork arm of the needle holder which thus straddles the bottom end of pit-- man 42, such bottom end playing in the recess 21 which is spanned by the pivot pin 5 by means of which the bottom end of the pitman and the needle holder are loosely connected together. The needle holder has a horizontally-extending bore 5 for the pintle pin 5; and has a horizontal bore 22 throughout its length, at the front side of the web 22 The bore 22 constitutes a thread pas sage. The inward end of the recess 21 inter sects this thread passage so that the threadnipper spring 23 may pass through the inward end portion of the recess 21 between the foot of the pitman and the thread or.

threads in the thread passage 22 to hold the needle thread whenever and as may be required.

The work-holding foot construction comprises a dependent bracket having a shank 24- that is secured by a screw 25 to the front end of the upper arm A, the shank 24: terminating in an angular outwardly-projecting foot 25 to the lower end of which by a pivot-.

screw 26 there is pivoted a work-holdingfoot carrier 27 that extends over the throat plate 28 The outward end of the work holding-foot carrier is bent upwardly and inwardly at 28 over the upper side of the angular foot 25 The free end of the bend at 28 is provided with an adjusting screw 29 the inward end of which impinges on the upper wall of the foot 25*. A suitable spring 30 is interposed between the carrier 27 and the under side of the foot 25. The spring tends to push the worlcholding foot 31 carried by its free end over the throat-plate downwardly and by adjustments of the screw 29 the work-holding foot 31 may be adjusted upwardly in relation to the throat plate 28. The front end of the work-holding foot is upturned at 32 easily to glide over goods held down'by it by the pressure of the spring 30. This spring pressure on the work-holding foot that glides over the goods when and if the sewing-machine head is bodily moved during stitchforming operations, is very useful whenever there are variations in the thickness of the goods, as for example in certain ribbed goods during the sewing of which the foot will be lifted automatically against the resistance of the spring 30. The foot 31 has on its upper side back of its needle hole an upstanding wall 33 adjacent the back side of the needle holeand forming a lateral abutment for the needle when in the goods, and the feed of the goods pulls the needlelaterally towards the wall. This is useful in diminishing needle breakage and skipping of stitches.

Emphasis is laid on the location of the pivotal connection at 26 of the pivoted end of the work foot. carrier. It is as closely adjacent the upper level of the throat plate as is consistent with the travel of goods across the throat plate 28, a goods way Y being formed between the throat plate and the under side of the work-foot carrier 21. By reason of such location, the abutment wall 33 moves practically vertically duringthe automatic or mechanical adjustments of the work-holding foot. It will be observed in the present case that there is no feed dog or means through the work plate for cooperation with the foot and needle. The foot has only negligible pressure on the goods except at ribs or seams, the carrier 27 being set so that the goods travel over the work plate in very gentle contact with the foot which is movable between the work plate and the un-- der end of the dependent guide G.

The bracket shank 24 while adjustable endwise to vary the working position of the work holding foot above the throat plate,

is fixed when in adjusted position. This stationary bracket constitutes the holder or carrier of the work holding foot which while movable on the lower end of the bracket has no reciprocating movement in cooperation with a feed dog, as is the case in most sewing machines. There is no feeding device in the sewing machine head herein shown; and" in machines in which my present invention has been incorporated, the feed of the goods has been effected by feed rolls spaced-apart from the sewing machine head. If the work holding foot herein described were comparable to the ordinary pressure foot of the usual sewing machine, its bracket shank 24 would have to be endwise movable in order to obtain the rise and fall or reciprocation of the foot synchronously with the movements of a feed dog and relatively to the throatplate.

What I claim is,-

In a sewing machine the combination gular under end portion of thebracket and p the work holding foot, the spring'functioning to hold the foot against the upper surface of goods between the throat plate and upper stitch forming instrumentality; and

move the foot into a lower position towards the goods while the foot is upwardly movable against the tension of the spring to permit goods to be fed freely between the throat plate and the foot and to prevent the spring from effecting a clamping pressure on the goods.

In testimony whereof I have hereunto set my hand this 27th day of December, 1918.

JOHN PETER WEIS.