US1733220A - Picot cutter for hemstitching machines - Google Patents

Description

Oct. 29, 1929. A. E. FARRELI. 1,733,220

PICOT CUTTER FOR HEMSTITCHING MACHINES Filed Oct. 26, 1925 la Prg. i-

"4 /4 O 3 ya INVENTOR ATTORNEY Patented Get. 29, 1929 UNITED STATES ANNA E. FARRELL, OF

SEATTLE, WASHNGTON PICOT CUTTER FOB, HEIVISTC-IING MACHINES Application led October 26, 1925.

This invention relates to devices adapted to be applied to a hem-stitching machine for cutting double-hem-stitched work to provide picot edges thereon.

The object of the invention is to provide an eiiicient device of this character whereby the picot cutting is done uniformly and expeditiously.

More specific objects and advantages of the invention will appear in the following description.

The invention consists in the novel construction, adaption and combination of parts hereinafter described and claimed.

In the accompanying drawing,-

Figure 1 is a view partly in side elevation and partly in vertical section of a portion of a sewing machine with an embodiment of my invention applied thereto, a part of the knife support being broken away. Fig. 2 is an end elevation taken from the left hand side of Fig. 1. Fig. 3 is a plan view of the throat plate of the machine. Fig. 4 is a perspective view of my cutter attachment illustrated in Figs. 1 and 2. Fig. 5 is a plan view of a piece of fabric illustrating the function of the invention. Fig. 6 is a side elevation of parts of a sewing machine showing a modified form of the invention, a part of the knife support be- 0 ing broken away.

In said drawing. the reference numeral 10 represents a portion of the arm member of a sewing machine in which is mounted for vertical movement a foot-bar 11 which carries the presser foot consisting of two companion elements 12 and 13.

As shown. the bar 11 extends through rectangular boss elements 14 and 15 of the shank or support 16 of the presser foot.

Secured within the top of the machine table is a throat plate 17 having parallel slots 18 to accommodate serrated feed bars (not shown) bv which the cloth is intermittentlf.7 fed in the direction indicated by the arrow in Figs. 1

4 and 6.

19 represents a machine-needle and 2() .a punch, two of each being employed in double hemstitching operations. All of the mao chine parts above mentioned are, or may be,

of any suitable or known construction.

Serial No. 64,759.

According to the present invention I provide a knife 21 which is secured by means of a hanger to the presser foot support 16 and arranged to operate between the presser foot elements 12 and 13 so as to progressively cut 55 the cloth between the double stitches.

Referring to Figs. 1 to 4, inclusive, the knife 21 is fermed with a horizontal straight lower edge 22 to seat against the surface 23 between the slots 18 of the plate 17 and, at its 60 forward end, the knife is provided with a downwardly directed toe 24 fitting within a slot 25 of said plate and against a stop 26 provided at the rear end of the slot. The front edge 27 of the knife is inclined to make an acute angle with the plane of the table and is beveled as at 28 to afford a sharp cutting edge which extends to the plane, at least, of the table top.

In the embodiment now being considered, the upper portion of the knife 21 extends between two lugs 29 depending from a hanger member 30, and is rigidly held to the hanger by means of a clamping screw 31 extending through apertures provided respectively in the lugs 29 and the knife.

The hanger 30, above referred to, consists of a body 33 of a substantially U-shape in transverse section providing at the top of each of its sides 34 a shoulder 35 which are adapted to be held in engaged relation with the underside of the boss element 15 of the presser foot support 16.

As shown, the4 means for retaining said hanger body in such engaged relation to the boss element consists in two supporting arms 36 extending upwardly from the body, one at each side of the boss, the upper ends of said arms being formed to provide fingers 37 directed toward each other to engage upon the top surface of the boss at diametrioally opposite sides of the foot bar 11.

The body supporting means, as shown, consist of plat-es which are secured by means of headed screws 33 to the hanger body. Said arms are arranged to embrace the boss 15 from opposite sides and hold the body firmly against the underside of the boss.

To prevent the hanger being accidentally displaced rearwardly of the boss 15 when the knife toe 24 is not engaged, I provide at one side of the hanger body a forwardly directed arm .39 which terminates in a linger et() engageable with the front side of the boss 15.

stantially the same'as the cevice before deo scribed with the substitution of a tiltable knife 211 for the relatively fixed knife 21; such tiltable knife being fulcrumed to the screw or pin 311 between lugs 29, the latter having frictional Contact with the knife sufficient to yieldably retain the knife in either its full line position (211) or in its dotted line position 212, when the knife is to be held in its inoperable and operable positions,l respectively.y

A thumb knob Ll2 is desirably provided upon the knife 2l1 to 4facilitate the tilting of the` same. This knife also is provided with a straight table engaging edge 221 and a downwardly protruding toe 241 which is adapted when brought into its dotted line position 242 to be engaged within the plate slot 25 (Fig. 3) to present the edge 271 of the blade in cutting position with .respect to the work. Y

The devicel as a whole is readily attached and disconnected to and from the machine by moving the hanger horizontally upon the boss: l5 after the operator renders the arm 39 temporarily ineffective by a thumb pressure against the finger 40 of the arm to be clearl of the boss l5. f

The character of the work performed by myl invention will be understood by reference to Fig. 5, wherein is shown a piece of cloth. C having two li-nes of hemstitches S conventionally known as double hemstitching with arow of holes H, made by the machinepunches, positioned 'intermediate said lines of hemstitching.

'These punch holes effect the gathering of the cloth threads between the successive holes and which gatherings of thread are-eut-generally by scissors-to providev tufted edges as indicated by P and known' in the art as Picot/77. l,

The knife of my devicer being arranged as hereinbefore described has its cutting edge in the path of the row of holes H (Fig. 5) so that the cloth when drawn beneath the presser foot encounters the knife to cause the latter to sever the threads between' the punch holes H thereof.

The devicey is easy to operate, and will accurately cut the cloth because the knife is li'rml'y held from lateral vibration by the engagement of itstoe element within the slot 25 Aof the stationary plate 17 in the machine table.

The device also is rmly held against longitudinal shifting and tilting by means of the toe cooperating with the stop 26 and having a bearing for the knife against the top of said plate and also by reason of its securement to the hanger 30 above the plane of the cloth. The hanger is connected to the presser foot shank or support for convenient removal when desired. Y

Vifhile l have illustrated and described embodiments of the invention now preferred by me, l do not confine myself specifically thereto except as limited by the scope of the following claim.

What I claim, is,-

A cloth-cutting attachment for a sewing machine, having a hanger member adapted to be; connected to the presser foot for vertical movement therewith, a single cutting knife rigidly secured to said hanger and carried thereby into position to have the knife extend below the upper surface of the machine table when the presser foot is depressed into operable position, and a resilient arm provided en the hanger and adapted to serve a latch with respect to the presser foot for detachably connecting the hanger andthe knife as a unit tothe presser foot.

Signed at Seattle, VVashi-ngton., this 23rd day of September 1925-.

ANNA E. FARRELL.

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