US1535025A - Automatic picot-cutting attachment - Google Patents

Description

April 21, 1925.

F. K. MARTINEK AUTOMATIC PIGOT CUTTING ATTACHMENT Filed March 27. 1922 2' Sheets-Sheet 1 INVENTOR. Jim/m f1. [Vanna/En:

ATTORNEY.

April 21, 1925. 1,535,025

' F. K. MARTINEK AUTOMATIC PICOT CUTTING ATTACHMENT Fi led March 1922 2 Sheets-Sheet 2 ATTORNEY.

tatented Apr. 21, 192.5.

UN! TE D 5 TA ream: K. amnrmnx, or -l\T-EW YORK, N. Y.

auroivrar c ricer-curative ATTACHMENT.

Application filed March 27, 1922. SeriatNo. 547,069.

To all whom it may-concern:

Be it known that I, FRANK K. MARTINEK, a citizen of the United States, residing at New York city, in the county of New York and State of New York, have invented certain new and useful Improvements in Automatic Picot-Cutting Attachments, of which the following is a specification.

This invention relates to an automatic picot cutting attachment for a sewing inachine and more particularly to a novel and improved removable device adapted to be carried by the presser bar of the machine.

The primary objectotthe invention is to provide a novel and improved attachment designed for useand cooperating with the conventional type of hemstitehing apparatus whereby the threads of the material of the hemstitching are severed to produce a picot edge.

One of the objects otthe invention is the construction of an automatic cutting attachment adapted to be mounted on the presser bar -liorcooperation with the piercer bar bracket including means for rendering the cutting element carried by said attachment inoperative or operative as the material is moved by the continuously, movable feed dog. I v

Another object of the invention 1s the provision of an attachment havingastationary and a movable cutting element cooperating therewith, said attachment being carried by the presserbar so that the cutting edges of the blades will be disposed rear-wardly of the needles, including provision whereby one of said blades will be moved for engagement with the ,piercer bar brackettoelfect the cutting of the material as the same is pierced b-y'the piercer.

lVith these and other objects in view the invention consists in the construction and novelcombination of parts hereinafter tully described, illustrated in the accompanying drawing, and'pointed out in the subject matter being claimed, it being understood that various changes in the form, proportion, size and minor details of construction maybe resorted to without departing from the spirit and scopeof the invention.

In the drawings, Figure 1 is a side view showing the invention in its operative position and as lTlOllHilQd on the presser-bar.

Figure 2 is a front view.

Figure 3 is a bottom view of the attachment as-shown in Figure '1.

v Figure 4: is an enlarged view partly in section of the attachment showing the cutting blades in theiroperative and inoperative positions. I

Figure 5 is-a section taken on'the line 5-5 of Figure 4 and Figure 6 is a further section taken on the line 166 of Figure 4.

Figure 7 is a view showing the hemstitching and the 'picot edge.

Referring now to the drawings wherein like reference characters designate corresponding parts throughout the several views, 5 designates a portion of the machine head and 6 the threaded bearing-for the upper end of the presser bar 7, said bar carrying an adjustable collar8 and a coiled springt) disposed between the said bearing and collar. as clearly shown by Figure 1 of the drawings. The frame 1Ov is. provided with the removable'throat plate 11 and theshuttle 12 is positioned beneath the feed dog 13 which is adapted to receive the respective shoes 1.4 of the 'presser foot 15. The .presser foot 15 is adapted to be'depressed by thespring 16 disposed between the top thereof and the collar 17 mounted on. the .presser bar 7. A securing collar 18-secured by a set screw 19 permits of the movement of-the upper part ofthe presser foot against'the spring 16 and maintains the shoes in their proper position 011 the work. The piercer bar 20 carries at its lower end-an L-shaped .piercer bar bracket 21 the lower curved end 22 of which is offset and carries the cloth ipiercer 23 disposed between the shoes 14- as shown by Figure 2' of the drawlng. This structure is old in the art and my nvention is dlrected to an attachment cooperating with the mechanism above. described and which will now be set forth in detail.

A slide carriageblock 25 substantially rectangular in crosssection is provided with a vfront extension '26, which extension is provided with a recess 27 whereby the slide carriage block 25 may be mounted on the lower end of the .presser bar 7 and 'be secured thereto by the screw 28 thus .properly maintaining the attachment on the spresser bar and in position adjacentthe -lo-wer*end of the presser foot. Theslide carriage block 25 re ceives a spring controlled. plunger or slide carriage 30 th-erei-n, said slide carriage havingastop Blon the top thereof to engage the block 2 5 to limit the inward movement of said .plunger. The-,pl-ungerslide carriage ill) is provided with a pair of diagonally positioned recesses 32 which recelve the springs 33, the said springs being also seated in recesses 34 in the slide carriage block and are adapted to maintain the carriage v and its knives in their inoperative position.

The carriage 30 is also provided with a spot hole 35 in one side thereof for receiving a lock pin 36 whenthe plunger 30 is moved inwardly of the block 25 so to dispose the cutting elements in their operative position. A lever 37 provided with an extension 38 is pivoted as at 39 in a recess in the side of the slide carriage block, one end of said lever having a slot 40 for engaging a stud 41 on the pin. The opposite end of the lever is enlarged to provide a finger piece 42 whereby said lever may be rocked on its pivot 39 against the resistance of a fiat spring 44, which spring is secured at one end to the slide carriage block and at its opposite end to a tension regulating screw 45. Since the slide carriage or plunger 30 frictionally rides within the slide carriage block 25, it will be readily seen that as the plunger 30 is forced inwardly, the pin 36 will fall in the spot hole 35 and thus maintain the said plunger in its locked position. However by depressing the lever 37 against the resistance of the spring 44, the pin 36 will of course be withdrawn from the spot hole and consequently thecoilsprings 33 hearing against the plunger 30 will force the same outwardly to its inoperative position. r

Referring now in particular to Figures 4 and 5 it will be observed that the bottom of the slide carriage block 25 is provided with a groove or recess for receiving the top reduccd portion 46 of a slide carriage block clamp 4-7, the same being fastened and secured to the slide carriage 30 by the screw 43. The said block clamp pivotally supports and carries the movable and stationary cutting knives 50, 51, which are held on the pin or screw 52 extending transversely of the said block clamp. The stationary blade or cutting element 51 is provided with a vertical extension 53 within. a recess in the is provided with a lug 58 hearing against a coilspring 57. The spring 57 urges the pin to the right, see Figure 6, so as to depress the end ()0 of the cutting knife 51. It will be observed that the rear end of the stationary :blade 51 is cut away at an angleso as to permit of its oscillation on the pivot 52, when the plunger is moved forwardly into operative position, the said cut away portion of the blade being adapted to bear against andride upon the bevelled edge 53 depending from the bottom of the slide carriage block 25 thus raising the front cutting edge as the plunger 30 moves rearwardly into inoperative position as clearly shown by Figure 4 of the drawing. The pointed front end 60 of the stationary blade is adapted to cooperate with the cutting edge 55' of the movable blade which is also pivotally mounted on the screw or pin 52 referred to. The movable blade 50, however, is provided with a curved tongue or extension which is movable to a position beneath the piercer bar bracket so as to be engaged thereby and thus be forced downwardly to engage the material between the shoes 14 thus severing the threads of the material and producing the desired hemstitching and the picot edge.

7 Of course the cuttin action of the blades 50 2D becomes noperative when the plunger or cal extension 58 which may oscillate in the slot 59 in the bottom of the slide carriage block 25. By this construction it will be readily seen that since the cutting edge 55* of the movable blade is normally maintained in its raised position since the spring pressed pin bears against the curved hook end 5?, as the plunger or slide carriage is moved forwardly and locks the curved tongue will be disposed beneath the 'piercer bar bracket 22 so as to be engaged thereby as shown in dotted line, see Figure 4. Consequently the curved tongue will be ('lQPlGSSQtl and the eutting edge 55" forced through the material, thus severing the material between the shoes 14. 'Of course when the slide carriage or plunger 30 is released or in its inoperative position, the blade 50 will not he engaged by the piercer bar b 'acket and the machine may continue in the regular sewing, or stitching of the material.

While I have illustrated and described my invention with some degree ofparticularity I realize thatin practice various alterations therein may be made. I therefore reserve the right and privilege of changing the form '.of the details of construction or otherwise altering the arrangement of the correlated parts without departing from thespirit, of the invention or the scope of the appended claims.

Having thus described my invention, what I claim as new, and desire to secure by United States Letters Patent is 1. An automatic p-icot cutting attachment in combination with the presser bar and piercer bar bracket of a machine, comprising a carriage block, means for mounting the carriage block on the presser bar so that it may extend rearwardly thereof, a resiliently controlled plunger slidable within the carriage block, means for locking the plunger in its operative position, cutting blades carried by the plunger, one of said blades being engageable by the piercer bar bracket when the slidable plunger is in its locked position.

2. An automatic picot cutting attachment in combination with the presser bar and piercer bar bracket of a machine, comprising a carriage block, a resiliently controlled plunger slidable within the block, means for locking and releasin the plunger to an op-' 37 erative and inoperative position, cutting ele ments movable with the plunger and means carried by one of the elements for engagement with the piercer bar bracket when the plunger is in its locked or operative position.

3. An automatic picot cutting attachn'ient in combination with the presser bar and piercer bar bracket of a machine, comprising a carriage block, a plunger slidable within the block, resiliently controlled, lever op erating means for locking and releasing the plunger to its operative and inoperative positions, cutting elements carried by the plunger, means for normally maintaining the cutting edge ot one of said elements in a raised position and means whereby said raised cut ting element may be actuated by the piercer bar bracket during its reciprocatory movement.

it. An automatic picot cutting attachment in combination with the presscr bar and piercer bar bracket of a machine, comprising a carriage block, a resiliently controlled plunger, slidablc within the block, means for maintaining said plunger in its locked, operative position, a stationary and a movable cutting element movable with the plunger, means formed on the movable cutting element for engagement with the piercer bar bracket and resiliently controlled means for rendering said cutting elements inoperative.

5. An automatic picot cutting attachment in combination with. the presser bar and piercer bar bracket of a machine, comprising a carriage block, a resiliently controlled plunger slidable within the block, means for locking the plunger in its operative posi tion, a block clamp secured to the bottom of the plunger, a stationary and a movable element pivotally mounted for vertical movement on the block clamp, means for depressing the front edge of the stationary cutting element when the plunger is moved to its op erative position, and a curved extension on the movable cutting element for engagement with the piercer bar bracket during its reciprocatory movement.

6. An automatic picot cutting attachment in conibination with the presser bar and piercer bar bracket of a machine, comprising a carriage block, a resiliently controlled plunger slidable within the block, means for locking and unlocking the plunger in its operative position, a block clamp and a horizontally pivoted pair of cutting elements carried thereby secured to the bottom of the plunger, means for depressing the front edge of one of the cutting elements, means for maintaining the cutting edge of the second cutting element in its raised position, and means formed on the last mentioned cutting element engageable with the piercer bar bracket during its reciprocatory movement.

7. An automatic picot cutting attachment in combination with the prcsser bar and piercer bar bracket of a machine, comprising a carriage block, a plunger slidable within the block, lever operated means for locking and unlocking the plunger in its opera tive position, a depending block clamp secured to the bottom otthe plunger, a pair of con'ii'nonly pivoted cutting elements carried by the block clamp, resilient means bearing against one of said elements when the ilunger is in its operative position whereby the front edge is depressed, means engaging the rear end of the second of said elements for normally n'iaintaining the front cutting edge in its raised position and means formed on the last mentioned cutting element for engagement with the piercer bar bracket during its reciprocatory movement.

In testimony whereof I atlix my signature.

FRANK K. h IARTIN EK. [1,. s]

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