US2675772A

US2675772A - Befringing means

Info

Publication number: US2675772A
Authority: US
Publication date: 1954-04-20
Anticipated expiration: 1971-04-20

Description

April 20, 1954 H, WEBB 2,675,772

DEFRINGING MEANS Filed Feb. 7, 1952 3nventor WaZze/ 15. 1 1 6 Q i Q- (Ittomeg Patented Apr. 20, 1954 UNITED STATES OFFICE DEFRINGING MEANS Application February '7, 1952, Serial No. 270,300

3 Claims.

The present invention relates to a rolled hem forming mechanism and particularly to a novel defringer device for use therein.

Heretofore defringer devices have been used in conjunction with a hemmer, of the type known as a twist hemmer, to turn in the fringed edges of the fabric so as to insure that they will lie within the rolled hem, thus producing a more satisfactory hem. Such prior defringers have been fixedly secured to the spiral hemmer and hence because of the fixed spacing would operate only on the material for which the hemmer was designed.

The present invention overcomes the difiiculties of the prior art by providing a separate defringer attachment which is adjustably mounted with respect to the hemmer so that the hemmer can be made to operate on various materials by suitably adjusting the defringer spacing with respect to the edge of the hemmer and can be adjusted independently of the hemmer so that it can be properly positioned without changing the adjustments of the hemmer. These are accomplished by providing a defringer member which is adjustably mounted on the base plate so as to extend transversely of the twist hemmer and which is provided with a curl at the end to lie adjacent the edge of the twist hemmer to properly direct the edge back into the folds of the material so that it will be completely enclosed therein.

Further, the defringer attachment can be applied to cooperate with existing twist hemmers without changing the structure of said hemmers.

Other features and advantages of the invention will be apparent from the specification and claims when considered in connection with the drawing in which:

Figure 1 shows a top plan view of a twist hemmer with the defringing attachment in place.

Fig. 2 shows a side view looking from the bottom of Fig. 1.

Fig. 3 shows a section taken along line 3-3 of Fig. 1.

Fig. 4 is a fragmentary View showing the defringing device adjusted into greater spaced relation than that of Fig. 1.

Fig. 5 shows a rolled hem such as produced by the present invention showing the edge secured within the hem.

While the device of the present invention may be applied to a sewing machine in many ways, in the preferred embodiment of the present invention it is formed as an attachment to be secured to the bed of a sewing machine in line with the feeding and sewing mechanism thereof as is usual. This attachment comprises a base plate it having an elongate opening II by which the attachment is secured to the bed by means of a bolt (not shown) passing therethrough. The twist hemmer comprises a pair of superposed spaced plates !2, it which are connected together at id and are preferably tapered as shown in Fig. 1. The plates are mounted on the base plate by means of a screw l5 extending through an extension IZCL on the plate and may be pivotally adjusted thereabout to line up with the sewing mechanism. The plates are twisted together lengthwise toward the needle to provide between them a spiral guideway IS extending toward the needle within which the edge of the fabric may be placed. The forward end of the guideway is flared as at Hid to aid in the insertion of the fabric. Movement of the fabric toward the needle will cause the material adjacent the edge to be folded over upon itself as it approaches the needle so that the edge is disposed within the rolled portion. One such hem is shown at IT in Fig. 5.

With same fabrics the raw edge of the fabric produces a fringed effect which has a tendency to be uncontrolled by the hemmer and to work out of the hem and to project therefrom and produce an unsatisfactory appearance. According to the present invention this is avoided by providing a separate defringing device l8 which cooperates with the hemmer to insure that the edge is turned into the hem. As herein illustrated the defringing device comprises an arm is having at one end an edge engaging curled portion 20 and having at its other end a slot 2| by which it may be adjustably mounted on the base plate to extend transversely of the hemmer intermediate the ends thereof by means of a clamping screw 22 passing through the slot and having an enlarged head 23 engaging the arm. While the edge engaging curl may be of any desired shape, it is at present preferred to provide it with a longitudinally extending curvature as shown in Fig. 1 so that it will follow the curve on the spiral on the hemmer and closely overlie the edge of the guideway as shown in Fig. 3 so as to accurately control the folding in of the fringed edge.

A feature of the invention resides in the fact that the defringing device being a separate member may be attached to any existing hemmer without in any way modifying the hemmer. Furthermore, since it is separate from the hemmer and has an elongate slot 2! in its mounting means it may be adjusted with respect to the hemmer without disturbing the adjustment of the hemmer in order that the device may accommodate different types of fabrics. This is clear from a Showing of Figs. 1 and 4 wherein Fig. 1 the adjustment is arranged so that the curl is closely adjacent the open edge of the guideway and will insure movement of fringed edges of fine fabrics, such as necktie fabrics, into the fold. In Fig. 4 the guide is positioned further away from the edge of the guideway and may be used to curl back the edge of heavier, stifier fabrics to aid in properly forming a rolled edge thereon. Also the device may be pivotally adjusted about the screw 22 to provide the required clearance all along the edge of the guideway without disturbing the adjustment of the hemmer.

Variations and modifications may be made within the scope of the claims and portions of the improvements may be used without others.

I claim:

1. A hemming attachment for sewing machines adapted to form a rolled edge on fabrics comprising a base plate adapted to be secured to the sewing machine in advance of the stitch forming mechanism, a pair of spaced longitudinally twisted guide members mounted on the base plate and forming a continuously twisting channel through which the edge of a fabric being hemmed may pass, and a defringer attachment comprising an arm having means at one end for adjustably mounting the arm on the base plate to extend transversely of the guide members intermediate the ends thereof and having a curl at the other end spaced inwardly from the free end of said twisted guide members a substantial distance and located adjacent the side of the guide members opposite said mounting means and spaced from the curved edges of the guide members in position overlying the same to turn the turning edge of the fabric into the folds of the fabric forming the rolled edge.

2. A hemming attachment for sewing machines adapted to form a rolled edge on fabrics comprising a base plate adapted to be secured to on the base plate to be aligned with the stitch forming mechanism, a pair of spaced longitudinally twisted guide members adjustably mounted on theb ase plate to be aligned with the stitch forming mechanism, said members forming a continuously twisting channel through which the edge of a fabric being hemmed may pass, and a defringer attachment comprising an arm having one end adjustably mounted on the base plate so as to extend transversely below the guide members intermediate the ends thereof and having a curl at the other end spaced inwardly from the free end of said twisted guide members and extending upwardly and overlying the edge of the twisted channel formed by the guide members to engage the turning edge of the fabric and direct it inwardly into the rolled edge, said arm being adjustable independently of said guide members to space the curled edge thereof in predetermined spaced relation to the side of said members in accordance with the fabric being used.

3. A hemming attachment for sewing machines adapted to forth a rolled edge on fabrics comprising a base plate adapted to be secured to the sewing machine in advance of the stitch forming mechanism, a pair of spaced longitudinally twisted guide members mounted on the base plate and forming a continuously twisting chan- V nel through which the edge of a fabric being hemmed may pass, and a defringer attachment comprising an arm having an elongate slot at one end for adjustably mounting the arm on the base plate to extend transversely and under the guide members intermediate the ends thereof at a point spaced inwardly of the free end of said twisted guide members and having a curl extending upwardly of the arm at the other end, said curl overlying the edges of the twisted guide members and having a longitudinal curvature corresponding to the curvature of the edges of the twisted guide members and being in spaced relation to said edges to overlie the same to engage the edge of the turning fabric and turn the edge of the fabric into the folds of the fabric forming the rolled edge.

References Cited in the file of this patent,

UNITED STATES PATENTS Number Name Date 1,857,058 Maier May 3, 1932 2,034,672 Ackerman Mar. 17, 1936 2,138,633 Greenfield et al. Nov. 29, 1938 2,621, 19 Enos Dec, 16, 1952