US2880685A - Hem-folding attachments - Google Patents

Description

April 7, 1959 A. M. GARDNER 2,880,685

HEM-FOLDING ATTACHMENTS T Filed Feb. 17. 1956 2 uvmvroa.

'9- Augusf M. Gardner W/ TNESS A TTOVBNEY United States Patent HEM-FOLDING ATTACHMENTS August M. Gardner, Elizabeth, N.J., assignor to The Singer'Manufacturing Company, Elizabeth, N.J., a

H corporation of New Jersey ApplicationFebruary 17, 1956, Serial No. 566,189

1 Claim. (Cl. 112---141) This invention relates to overedge sewing machines and more particularly to 'means embodied therein for hem-folding the marginal portions of both fiat and tubular work-pieces and for so presenting the folded workpieces to the trimming and stitch forming mechanisms that the projecting edge portion of each work-piece is trimmed substantially in line with the fold and the hem is secured to the body material by a blind-stitch overedge seam.

A primary object of the invention is to provide an improved hem-folder which, although most efficient in operation, is at the same time adapted to be applied readily to a conventional type of sewing machine without the necessity of adding to the machine any special fittings in the way of brackets, bolts, clamps or the like.

Another object of the invention is to providesuch a hem-folder attachment that may be swung about a horizontal axis to the end that the folder may be removed from its operable position thereby to facilitate certain sewing operations.

With the above and other objects in view, as will hereinafter appear, the invention comprises the devices, combinations and arrangements of parts hereinafter set forth and illustrated in the accompanying drawings of a preferred embodiment of the invention, from which the several features of the invention and the advantages attained thereby will be readily understood by those skilled in the art.

In the drawings:

Fig. 1 represents a fragmentary top plan view of a portion of an overedge sewing machine fitted with the present hem-folder.

Fig. 2 represents, on an enlarged scale, a left-hand elevational view of a presser-foot employed in the present machine, which resser-foot has incorporated therein the present hem-folder.

Fig. 3 represents, on an enlarged scale, a right-hand elevational view of the presser-foot with the present hemfolder attached thereto.

Fig. 4 represents a front elevational'view of-the device disclosed in Fig. 2.

Fig. 5 represents a sectional view taken substantially along the line 5-5 of Fig. 3.

Referring to the drawings, the invention is shown as embodied in an overedge sewing machine of the type disclosed in the U. S. patent of N. Knaus, No. 2,238,796, April 15, 1941. Furthermore, the present invention represents an improvement over the hem-folding attachment disclosed in the U. S. patent of N. Knaus et al., No. 2,649,066, August 18, 1953.

Referring to Fig.1 of the drawings, the sewing machine partially illustrated therein comprises a usual type of overedge sewing machine comprising a base frame portion and an upstanding portion 12. The base portion 14 carries a horizontally disposed work-supporting plate 13 and a throat-plate 14 provided with slots (not herein shown) through which operate the usual feed-dogs which, since they do not form a part of the present invention, are not disclosed herein. The main frame also supports the usual overedge stitch-forming mechanism including a reciprocatory curved needle 15 and an overedge loop ice 2 spreader 16 which cooperates with the needle "15 in the formation of overedge stitches.

The present overedge stitching machine also includes a conventional presser device comprising a horizontally disposed spring-depressed presser-bar 17 pivoted at its rear end to the machine frame andcarrying at its forward end a presser-foot 18 which overlies the throatplate 14 and the feeding mechanism which is not herein disclosed.

The machine further includes a trimming mechanism adapted to trim the work at one side of the line of seam formation. The trimming mechanism includes a vibratory trimmer bar 119-actuated from the main shaft ofthecm'achine and carrying at its forward end a "movable trimmer blade 20 which cooperates with a stationary trimmer blade carried by the base portion of the-machine frame and not disclosed herein. Inasmuch as the specific constructions of the stitch-forming, work-feeding and worktrimming mechanisms are shown in the above mentioned Knaus Patent No. 2,238,796 andform no part of the present invention, further illustration and description thereof is deemed unnecessary.

As hereinabove indicated, this invention relates primarily to improved means, provided in the machine of the type above described, for so presenting a work-piece to the stitch-forming mechanism that the marginal portion of the work is folded into flattened S shape, with the uppermost portion thereof trimmed substantially in verical alignment with the lowermost fold. The needle 15 thereupon penetrates the upper part of the work adjacent the trimmed edge and passes through the underlying .fold entering and then merging from the same face of the work, all in a manner as described in the above noted Knaus et a1. Patent No. 2,649,066. I

The present hem folder is adapted to be secured upon the sewing machine resser-foot 18. This presser-fo'ol comprises an elongated sole-plate 21 which is provided in its upper portion with the groove 22 for receiving therein the depending portion 23 of the .presser-ba'r 17 about which the presser-foot is pivotally mounted. The resser-foot 1% is maintained in its pivotal relation relative to the presser-bar by means of'an arm 24 secured to the presser-foot by means of a screw 25. Referring particularly to Fig. 1, it will be noted that the arm 24 extends rearwardly so as to overlie a laterally extending portion 26 of the presser-bar thereby 'to'provide a pivotal connection between the presser-bar and the .presser-foot.

Projecting upwardly from the forward end of the soleplate 21 is an inclined presser-foot ftoe 27, the upper'portion of which is provided with a groove 23 which is disposed crosswise of the presser-foot and of the direction of work feed. As will hereinafter be described, this groove 28 is adapted for receiving therein a member which carries the present hem-folder device. For a more complete description of a presser mechanism of the present type, reference may be had to the U. S. patent of N. Knaus, No. 2,41%,494, April 22, 1947.

A preferred form of the present hem-folder device com prises a substantially L-shaped platform member includ ing limbs 29 and 30. Referring particularly to Figs. and 2, the limb 29 is slidably mounted Within the resserfoot toe groove 28 and is adapted to be secured .in a selected position of crosswise adjustment of the presserfoot by means of a screw 31 which passes freely through an elongated slot 32 provided in the limb 29. The limb 30 has formed therein a cylindrical'opening 33 which is disposed in parallelism with the direction of work feed and in which is rotatably mounted a stub shaft 34. As best disclosed in Fig. 3, the left-hand end portion of the shaft 34 is provided with an enlarged head 35 while the right-hand end portion of the shaft passes out of the limb 30 and is secured imposition by means of a 'cfillar 36 and a set screw 37 which locks the collar in position upon the distal end portion of the shaft 34. Formed crosswise of the head portion 35 of the shaft 34 is a cylindrical aperture 38 which, as will be hereinafter described, carries a wire hem-folder element. The free end portion of the shaft head 35 is appropriately threaded to receive a set screw 39 which, as will hereinafter be described, functions to lock the wire edge folder within the aperture 38.

The present hem-folding portion of the attachment includes a horizontally disposed U-shaped wire member including upper and lower limbs 41 and 42, of which the lower limb 42 is adapted to enter between the plies of the folded work and hold the folded right-hand edge of the work against a floating edge guide of the type provided in the machine disclosed in the above U.S. patent of Knaus, No. 2,238,796. The left-hand folded edge of the work engages the crotch portion 43 of the U-shaped wire member. More specifically, the present hem-folder element comprises a length of wire which is bent intermediate its two ends into a substantially U-shaped member including the above noted upper and lower limbs 41 and 42, which member receives the inner fold of the work-piece. It will be observed that the limbs 41 and 42 of the U-shaped member are disposed when in their operable position, as disclosed in Fig. 4, in substantial parallelism with the plane defined by the lower or active face of the presser-foot 18. The free end portion of the upper limb 41 enters the aperture 38 provided in the head portion 35 of the stub shaft 34 and may be locked in a selected position within said aperture by means of the set screw 39. From this it will be appreciated that the U-shaped wire member may be adjusted crosswise of the direction of feed in either one of two ways. For example, the entire U-shaped member together with the L-shaped platform element may be shifted crosswise of the direction of feed by adjustment of the lock-screw 31. An alternative adjustment is to shift the wire member within the aperture 38 and thereafter lock it in a selected position by means of the set screw 39.

The free end portion of the lower limb 42 is bent at right angles to the plane defined by the first U-shaped member and forms an arbor 44 about which the outer fold of the work-piece is wrapped. This arbor 44 is bent backwardly from the first U-shaped member in the line of scam formation and, as is best disclosed in Figs. 1 and 2, it terminates at a location directly beneath the upwardly inclined toe portion 27 of the presser-foot. Thus, this wire hem-folding unit is carried entirely by the presserfoot and after it is properly adjusted relative to the foot by means of the screw 31 it forms an integral part of the foot. Referring particularly to Figs. 1, 2 and 3, it will be observed that the arbor portion 44 of the hem-folder is slabbed at its upper and lower portions 45 and 46 so as to give a tapered effect to the arbor in order to facilitate the passage of work thereabout. Also, it will be observed from Fig. 4 that the lower surface 47 of the lower limb 42 is slabbed so as to reduce the diameter of the lower limb in order to facilitate the passage of work thereabout.

By mounting the present hem-folder wire upon the presser-foot, an integral unit is produced which, in re sponse to actions of the feed-dog, will pivot about the presser-bar and facilitate the passage of work therethrough. Also, it will be appreciated that as variations occur in the work, such as due to cross seams, the present hem-folder device will be permitted to move up and down with the presser-foot so as properly to accommodate such work.

Those skilled in the art will readily appreciate that sometimes it is desirable to employ such an edge-folder intermittently and, thus, it is helpful if such a device can be thrown into and out of operation without removing the same from the sewing machine or the presser-foot itself. In order to facilitate such operations the present wire hem-folder may be swung from its operative posi- '4 tion as disclosed in solid lines in Fig. 4 to an inoperative position as is illustrated by the dotted line view of Fig. 4.

More specifically, the wire edge-folder is maintained in its operative position as disclosed in Fig. 4 due to the fact that the upper limb 41 rests upon a lip portion 48 carried by the limb 30 of the platform member. When the operator wishes to remove the wire edge-folder from its operative position, it is merely necessary to grasp the crotch portion 43 thereof and swing it in a clockwise direction as viewed from Fig. 4 so that the unit will swing about a horizontal axis provided by the rotary shaft 34. As may be best observed from Figs. 1 and 4, the clockwise movement of the wire hemmer will be arrested by a stop element 49 formed on the outer extremity of the platform limb 30.

Referring particularly to Figs. 1, 3 and 5, means are provided for releasably locking the wire edge-folder element in its retracted position. This means includes a substantially L-shaped spring including limbs 50 and 51, of which the limb 50 is secured directly to the limb 30 of the platform member by means of a screw 52. As may be best seen in Fig. 5, the limb 51 of the spring is adapted to engage the shaft collar 36 which is secured to the shaft 34 in a manner such that a slabbed portion 53 thereof will be engaged by the limb whenever the wire edge-folder is in its operable position. From this, it will be appreciated that the limb 51 of the spring will function to maintain the edge-folder in its operable position but that the operator may readily overcome the force of the spring and shift the edge-folder to its inoperable position by a mere flick of the finger.

From the above, it will be understood that the present device is not only most efficient in use but at the same time it presents a unit which may be most economically manufactured and exploited commercially.

Having thus set forth the nature of the invention, what I claim herein is:

A sewing machine hemming attachment comprising, a presser-foot including an elongated flat-bottomed soleplate, and a toe projecting from the forward end of and being inclined upwardly relative to the fiat bottom of the sole-plate; a shaft disposed lengthwise of the sole-plate; means mounting the shaft upon the elevated end of the presser-foot toe for turning movements about its longitudinal axis; a work-folding member including a length of wire bent intermediate its two ends into a substantially U-shaped member whose two limbs when in operative position are disposed in substantial parallelism with the plane defined by the flat bottom-surface of the sole-plate and with the plane defined by the two limbs disposed at all times at right angles to the plane defined by the flat bottom surface of the sole-plate; the free end portion of a first limb of the member being bent at right angles to the plane defined by the two limbs and extending when the member is in its operative position lengthwise of the sole-plate and terminating directly in front of and beneath the level of the top of the inclined presser-foot toe; means securing the free end portion of the second limb of the member upon the shaft whereby the member may be swung upwardly about the shaft axis and away from its operative position to an inoperative position wherein the free end of the first mentioned limb is disposed above the level of the top of the inclined presser-foot toe; and means carried by the presser-foot toe releasably maintain ing the shaft and the work-folding member in their operative and inoperative positions.

References Cited in the file of this patent UNITED STATES PATENTS 359,452 Lavigne Mar. 15, 1887 877,659 Maus Jan. 28, 1908 2,649,066 Knaus et a1 Aug. 18, 1953 FOREIGN PATENTS 115,884 Sweden Feb. 19, 1946

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