US1182949A - Presser-foot mechanism for sewing-machines. - Google Patents

Description

I. L. WHEELER.

PRESSER FOOT MECHANISM FOR SEWING MACHINES.

APPLICATION FILED MAR. 6, I9I4.

Patented May16,1916.

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UNITED STATES PATENT OFFICE.

- JOHN L. WHEELER, OF ST. LOUIS, MISSOURI, ASSIGNOR, BY MESNE ASSIGNMENTS, TO I SIMPLE-X SHOE MACHINERY COMPANY, OF ST. LOUIS, MISSOURI, A CORPORATION OF MISSOURI.

Specification of Letters Patent.

Patented May 16, 1916.

Application filed March 6, 1914. Serial No. 822,800.

To all whom it may concern Be it known that I, JOHN L. WHEELER, a citizen of the United States, residing in the city of St. Louis and State of Missouri, have invented new and useful Improvements in Presser-Foot Mechanisms for Sewing-Machines, of which the following is a specification.

This invention relates to sewing machines, and more particularly to resser-foot mechanisms for machines for sewing leather and other heavy material.

It has for its principal object to produce a simple, compact and durable device which will effectively hold the work while it is being punctured by the awl or the needle, as the case may be; to provide for the automatic adjustment of the device for different thiclmesses of work; to provide for the release of the device from the work while the latter is being shifted for each succeeding stitch; and to attain certain advantages which will hereinafter more fully appear.

The invention consists in the parts, and in the arrangements and combinations of parts hereinafter described and claimed.

In the drawing,Figure 1 represents a side elevation of a sewing machine equipped with a work-holdin device according to the invention; and Fig. 2 is a fragmentary view, partly in section and partly in side elevation, showing how the work-holding device may be operated when its locking means is released.

'The sewing machine illustrated in the drawing is of the type known as the looplock-stitch machine. That is, it employs two threads, one which is termed the needle thread or stitching thread, and which is looped successively through the work, and the other the locking thread, which is interlooped successively through the loops of the stitching thread to provide a look therefor when the stitchesare set. Such a machine is described with more particularity inthe patent to Savignac and Myers, No. 1,016,898, of February 6th, 1912, and also in an application for patent, Ser. No. 807,225, filed by myself and one Charles E. Myers, on the 17th day of December, 1913.

Briefly stated, the machine comprises a head-frame 1, at the front of which is a work support or table 2. To the rear of the work support is a transverse, horizontal rock shaft 3, on which is fixed an oscillatory awl carrier 4:. A transversely oscillating awl holder 5 is mounted on said carrier, and it has an arcuate awl 6 thereon which reciprocates through an opening 7 in the work table. Devices are employed for effecting the lateral oscillation of the awl holder during its reciprocatory strokes, so that the work is fed by the awl while it is in the work and whereby the awl is restored to puncturing. position after it has receded from the work.

Rocking about the shaft 3 is a needle carrier 8 having an arcuate needle 9 thereon adapted to carry a loop of the stitching thread 10 through the pimctnre made by the awl. Both of the oscillatory carriers 4: and 8 are provided with segmental gears meshing with tooth sectors on rearwardlyextending rocking levers 11 which are respectively actuated in timed relation by cams provided therefor on disks 12, which latter are mounted on a transverse driving shaft 13 to the rear of the head frame.

Pivoted at the side of the head frame 1 is a lever 14. This lever has a forwardly and laterally extending portion 15 which constitutes the work holder or resser-foot.

The lever is also provided with a rearward and upward extension 16 at the outer end of which is secured one end of a spring 17 whose opposite end is attached to a stud 18 near the top of the head frame. The spring 'yieldingly'holds the lever with its rearward extension in raised position, and its forward extension down upon the work.

Mounted on the side of the head frame is a bracket member 19 having a guide-opening or slide-way 20 therethrough for a bar The lower end of the bar has a slot and-pin connection with the lever extension 16, as'at 22. The upper portion of the bar is provided with a series of relatively fine teeth or serrations 23 adapted to be engaged by similar teeth on a locking pin 2 1 which works through a transverse opening in the bracket member 19. A spring 25 is provided so as to move and yieldingly' hold said locking pin normally outward free from engagement withthe bar 21, and incontact with an adjustable stop 26 on an arm of a rocking lever 27, which latter is pivoted, as at 28, between lugs 29 extending rearwardly from said bracket member 19. The opposite arm 30 of this rocking lever is provided at its end with a roller 31 which rides on the cam disk 12; and said cam disk is provided with two peripheral recesses 32, The recess 32 is positioned on the disk so that the roller 31 rests therein when the needle is in its uppermost position and the awl is entirely below the work table, or, in other words, at the proper time for placing the work in and removing it from the machine. The second recess 33 is positioned in timed relation to the actuation of the awl, so that the roller 31 rides into said recess just before the awl begins its oscillatory stroke to feed the work, and it remains therein during the completion of the stroke. The length of said recess 33 is governed by the maximum length of the stitch made by the machine.

In the operation of the device the presserfoot is raised by the operator depressing the rearward extension of the lever la r; a suitable knob or handle 31 being conveniently provided therefor. As soon as the work is placed under the presser-foot the handle 31 is released by the operator and the spring 17 raises the rearward extension of the lever and yieldingly holds the presser-foot upon the work. This manipulation and ac- .tuation of the presser-foot is permitted because the roller 31 is in the recess 32 and the rocking lever is in a position which permits the withdrawal of the locking pin 2% from engagement with the bar 21 by the spring 25. As soon as the machine is started the roller 31 rides out of the recess 32 and onto the peripheral face of the disk 12, whereby the lever 27 is moved so as to push the locking pin 24 into engagement with the bolt 21. Hence, the presser-foot is rigidly held upon the work while the awl is puncturing the latter. Then, as stated above, the recess 33 is brought into position to receive the roller 31 just after the awl has completed its puncturing stroke and before it begins its lateral oscillatory stroke to feed the work to bring the puncture in line with the needle. After the awl has completed this lateral oscillatory stroke, the presser-foot is again locked by reason of the roller 31 riding out of said recess 33.

By the construction and arrangement of the parts of the presser-foot mechanism herein set forth the presser-foot adapts itself automatically to different thicknesses of work and compensates for any unevenness or variation in the thickness in the piece of work which is being sewed. That is, the spring 17 yieldingly holds the presser-foot in contact with the work all the time the work is in the machine except when the presser-foot is raised by the operators ma nipulation thereof. I

Obviously the device admits of considerable modification without departing from the spirit of the invention. Therefore, I do not wish to be limited to the specific consion, a spring acting upon said lever to raise the rearward extension of the latter and to hold the forward extension thereof yieldably upon the work, a bracket on said headframe above said rearward lever extension, a bar slidably mounted on said bracket and having a slot-and-pin connection at its lower end with said rearward lever extension, a locking member slidably mounted on said bracket so as to move transversely with respect to said sliding bar, the inner end of said locking member and the adjacent side of said sliding bar being arranged and adapted for the locking engagement of the former with the latter, a spring acting upon said locking member to move it out of'engagement with said sliding bar, a lever mounted on said bracket and having an upward extension in cooperative relation to said locking member so as to move the latter into engagement with said sliding bar, said last-mentioned lever also having a rearward extension, and a rotating cam disk with which said last-mentioned rearward lever extension cooperatively engages, said cam disk having two recessed portions in timed relation so that said locking member is released from engagement with said sliding bar during the time the work is being shifted for each succeeding stitch and at the time for placing the work in, and removing it from, the machine.

2. In a sewing machine, a head-frame, a work support thereon, a work-piercing device, means for feeding the work, a lever mounted on said head-frame and having a forward extension cooperating with the work support for holding the work on the latter, said lever having a rearward extension, resilient means acting upon said lever to hold the latter yieldably upon the work, a supporting bracket on said headframe, a sliding bar on said supporting bracket having a slot-and-pin connection with the rearward extension of said lever, a looking element movable on said supporting bracket transversely with respect tand arranged and adapted to engage said sliding bar with looking effect, resilientmeans acting upon said locking element to move the latter out of engagement with-said sliding bar, a lever mounted on said supporting bracket and having an extension in coiiperative relation to said locking element so as to move the latter into engagement With said sliding bar, and a cam element rotating in cooperative relation to said last mentioned lever and having provision whereby the lever is actuated to effect the locking of said sliding bar during the time the Work-piercing device is operating to puncture the Work, and the sliding bar is released of its lock periodically to permit the feeding of the Work and the placing of the Work in and its 10 removal from the machine.

In testimony whereof, I have hereunto set my hand in presence of tWo subscribing Witnesses.

JOHN L. WHEELER. Witnesses:

G. A. PENNINGTON, STELLA HILL.

cm" of this patent may be obtained for five cents each, by addressing the Commissioner of Patents. Washington, D. C.

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