US1733515A - Presser-foot mechanism for sewing machines - Google Patents

Description

Oct. 29, 1929. H, REED 1,733,515

PRESSER FOOT MECHANISM FOR SEWING MACHINES Original Filed Nov. 11. 1922 [Va/enforc/Qzfio rneys.

Patented Oct. '29, 1929 UNITED STATES PATENT OFFICE? JAMES 311mm SWAMPSCOTT, MASSACHUSET assrenon, Y MESNE ASSIGN- MENTS, TO UNITED snon MACHINERY conronarron, or rArnnson, "NEW ma SEY, A CORPORATION OF NEW JERSEY PRESSER-FOOT MECHANISM, non snwrive'ivmcnmns' Original application filed November 11, 1922, Serial 1705600324. Divided and this application filed October 20, 1923. Serial 'No'. 669,829.

This invent-ion relates to presser-foot mechanism and especially, although. not exclusively, to presser-foot mechanism for lock stitch shoe sewing machines of the general type shown in Patent No. 1,482,619 dated February 5, 1924:, and in my prior application for Letters Patent, Serial No. 542,666, filed March 10, 1922, on which Patent No. 1,688,056 issued October 1.6, 1928, the present application being a division of application Serial No. 600,224, filed November 11, 1922, on which Patent No. 1,706,743 issued March 26, 1929. p

This invention has for its object to provide 5 improved presser-foot operating means of such a character as to insure the lifting of the presser-foota constant distance above the work irrespective of the thickness of the lat.-

ter.

This and other objects of the invention, together with means whereby the same may be carried into elfectfwill best be understood from the following description of'a preferred embodiment thereof illustrated in the accom- 25 panying drawings, in which--- bodied in a machine of the type described in my prior application above referred to. Said machine is adapted primarily for sewing r shoes of the McKay type, but is also capable of use for many other purposes, as, for eX- ,45 ing work-supporting horn 17 having in its The invention is herein illustrated asemtipanoscillating looper or whirl l8 supplya cop or needle thread I The needle is carried by a needle bar 19 which is connected by a link 20 with a lever 21 pivoted in the head frame/22 and oper ated by a cam 23 on the main shaft 24 Journalled in said head frame 22 and adapted to receive'powerfrom any suitable source.

The shuttle 16 is'of the discodial type and ismounted ina shuttle race 27 supported at the bottom ofthe head frame 22 ina position to hold the shuttle with its front face slightly inclined to the path of the needle. The shuttlehas a hook 28 projecting from its front face and extending circumferentially there of, the arrangement being such that, as the shuttle is oscillated, said hookwill cross the] path of the needle, take the loop therefrom, and'cast the same over the shuttle," said hook passing at one side of the path of'the needle when in its uppermost position.- 7

.Thefwhirl 18 is oscillated, by mechanism not shown herein, to place a loop of cop threadin the openhook ofthe needle 15 when the latter is in its lowermostposition, said loop being taken from] the needle,when the latter rises, by the shuttle 16, and the'shuttle a 7 thread being explained. s

Between i the formation of, successive stitches, t he work is fed forwardly by means of a four-motion feed point'or and 42 The parts thus far referred to, exceptas theyenter into combination with the parts hereinafterdescribed,-f specifically form no portion of the present invention andmay be of any suitable construction and l arrangement. They will, therefore, not be further discussed herein, as theyare fully shown and described in my priorfapplication above referred to, andthe foregoing explanation of their nature and function will besufiicient for a completeunderstanding ,ofvthe inven* tion about to be described. I

'1- The work W is,duringthe stitch-forming passed tl1erethrough,as above operations, clamped upon the work-supporting horn 17 by a presser-foot 34 carried by a presser-foot bar 35 guided for vertical movement in the head frame 22. Said 1 presser foot is pressed toward the work by a torsion spring 86 carried by a rod 37 supported at its ends in brackets 38 and 39 secured to the top of the head frame 22, said cam'23. The arrangement is such that, when the dog 44 is raised by the lever 45, it will first turn upon its pivot to engage the presser foot bar with'a'clamping pressure,the slide 43 bein then lifted by the lever 45, acting through the dog 44,.and carrying with it the presser foot bar. As the dog 44 is released by the lever 45, it will,'-in' turn, release the presser foot bar35,:permitting the spring 36 to depress the latter, the slide43 being independently depressed by a spring 46 to an extent determined by the engagement of an adjusting screw 47 carried by said slide with an adjacent portion of the head frame 22. The stroke of the lever being constant, it will be seen that the movement imparted to thesl'ide 43 will depend upon the adjustment of the screw 47 being, however, constant in amount for each adjustment of said screw. The slide 43 and dog 44 constitute an intermittent grip device which cooperates with the presser-footbar 8 5t'0 lift the latter a predetermined amount, irrespective of the initial position of said bar, this amount" being equal to the amount of movement of said slide It will,therefore,'be seen that, irrespective of thethickness of the work W, the

' presser-foot 34 will at each operation of the machine be lifted the same distance above the upper surface of the work, this amount being determined by adjustment of the screw 47. 1

Thepresser-foot maybe lifted vby the op- I erator in order to permit the insertion or V removal of the work by means of a lever 48 fulcrumed upon the bracket 39 and engagmgr at its forward endan opening. in the presser footbar3'5, said lever being operated through suitable connections bya'treadle not shown):- at the base of the machine. 7

Having thus described my invention, I claim:

In a sewing machine, in combination, a work s'upport, a? head frame, an operating shaft j'ournalled in said fra1ne,as presserfoot bar guidedyin saidfr'ame, a; presser foot. carried thereby and: cooperating; with said work'support, a s'lide guided 'On"said presser- 7 JAMES H. REED.

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