US3859937A

US3859937A - Method of and apparatus for feeding a workpiece to a dart-forming sewing machine

Info

Publication number: US3859937A
Application number: US472991A
Authority: US
Inventors: Horst Fenzl
Original assignee: Duerkoppwerke GmbH
Current assignee: Duerkoppwerke GmbH
Priority date: 1973-05-25
Filing date: 1974-05-24
Publication date: 1975-01-14
Anticipated expiration: 1992-01-14
Also published as: FR2230774A1; DE2326683C3; JPS5036257A; DE2326683A1; GB1441723A; JPS5646879B2; DE2326683B2; IT1012717B

Abstract

A fabric workpiece is laid right side up on a flat table adjacent and transverse to the bed of a dart-forming sewing machine. A predetermined location on the workpiece is positioned over an aparture in the table in line with the bed and a folding element comprising a row of needles projecting from a reciprocal bar is pushed against the workpiece at the aperture and through this aperture to form a fold in the workpiece and displace this fold to the stitching location of the sewing machine. The table extends at an angle of approximately 75* to the bed of the sewing machine and is provided to each side of the aperture slot with an elastic lip formed by a coil spring that serves to guide and hold the fold.

Description

United States Patent Fenzl Jan. 14, 1975 [54] METHOD OF AND APPARATUS FOR 3,773,002 11/1973 Burton l12/121.l2

FEEDYNG A WORKPIECE TO A FOREIGN PATENTS 0R APPLICATIONS DART'FORMING SEWING MACHINE 1,660,839 5/1971 Germany ll2/l3l Inventor: Horst Fenzl, Oerlinghausen,

Germany Assignee: Durkoppwerke Gmbll, Bielefeld,

Germany Filed: May 24, 1974 Appl. No.: 472,991

Foreign Application Priority Data May 25, 1973 Germany 2326683 References Cited UNITED STATES PATENTS Davidson ll2/ 150 X Primary Examiner-H. Hampton Hunter Attorney, Agent, or Firml(arl F. Ross; Herbert Dubno [57] ABSTRACT A fabric workpiece is laid right side up on a Hat table adjacent and transverse to the bed of a dart-forming sewing machine. A predetermined location on the workpiece is positioned over an aparture in the table in line with the bed and a folding element comprising a row of needles projecting from a reciprocal bar is pushed against the workpiece at the aperture and through this aperture to form a fold in the workpiece and displace this fold to the stitching location of the sewing machine. The table extends at an angle of approximately 75 to the bed of the sewing machine and is provided to each side of the aperture slot with an elastic lip formed by a coil spring that serves to guide and hold the fold.

10 Claims, 2 Drawing Figures METHOD OF AND APPARATUS FOR FEEDING A WORKPIECE TO A DART-FORMING SEWING MACHINE CROSS-REFERENCE TO RELATED APPLICATION 5 The present application is related to the commonly assigned and copending application Ser. No. 471,645 filed on May 20, 1974 by Konrad POLLMEIER for a WORKPIECE GUIDE FOR SEWING MACHINE.

FIELD OF THE INVENTION The present invention relates to an apparatus for BACKGROUND OF THE INVENTION There is known a sewing machine in which the workpiece is fed past a sewing station between two surfaces which have a folding element displaceable toward the sewing station and serving to feed the workpiece in a folded condition between the guide surfaces of the sewing apparatus.

In such a machine the fabric workpiece after being folded at the requisite place is fed to a driven advancing bar or element which transports this workpiece to the stitching station of the sewing machine so that a gusset or dart may be formed in the workpiece. This apparatus comprises a displaceable base plate whose edge turned toward the advancing element constitutes a folding bar which in its starting position is overhung by an as yet unfolded workpiece. After orientation of the workpiece with the aid of conventional orienting means,

such as light spots generated by marking lamps, the

base plate with the folding bar goes through a folding channel thereby folding the workpiece in the region of dart to be formed and lays the folded workpiece under the raised ready advancing element which takes over the further transport of the prepared workpiece toward the sewing station. The displaceable base plate returns to its starting position in order to take the next workpiece to the sewing machine. Such an apparatus is disclosed in German Pat. No. 1,660,839.

This sewing apparatus does indeed aid in the production of garments having darts wherein the apparatus can be loaded automatically with prepared pieces. However, the workpiece must be placed on the base plate and folding bar with the wrong side up so that its right side is not visible to the operator. With solid-color fabrics it is irrelevant where the dart is placed in the garment so that the fact that only the wrong side of the goods can be seen is irrelevant. However, with fabrics having patterns, prints or the like it is impossible to arrange the dart so that they fall at a place in the pattern where they will be least obvious.

OBJECTS OF THE INVENTION It is therefore an object of the present invention to provide an improved apparatus of the abovementioned general type.

Another object is to provide an apparatus for folding and feeding the fabric workpiece to the stitching station of a sewing machine.

Another object is an improved method of feeding a workpiece to the stitching station of a sewing machine.

SUMMARY OF THE INVENTION The above objects are attained in accordance with the present invention in an apparatus having a table arranged adjacent and transverse to the plane of the bed of the sewing machine and formed adjacent to the stitching station of the sewing machine with an oper ture or slot. A folding element is provided which is reciprocal through the aperture through the station to push a fold of the workpiece at the location through the aperture along the bed of the station. The workpiece is arranged with a predetermined location on its surface in line with the aperture so that the fold will be formed at this location.

According to the method and apparatus of the present invention it is possible to form folds at a desired location on the workpiece since this workpiece is laid right side up on the table. It is possible for an experienced worker to very rapidly feed workpieces to the stitching location of a dart-forming sewing machine.

In accordance with other features of this invention the table is a slotted plate extending at an angle of between and 80 to the planar bed of the sewing machine. This plate is provided adjacent the slot-forming aperture with a pair of elastic lips constituted by a single coil spring which serves to guide and hold the fold as it is pushed therethrough.

According to yet another feature of this invention the folding element comprises a reciprocal bar and an array or row of parallel needles arranged on the bar directed toward the station.

BRIEF DESCRIPTION OF THE DRAWING The above and other objects, features, and advantages will become more readily apparent from the following, reference being made to the accompanying drawing, in which:

FIG. 1 is a side sectional view of the apparatus according to this invention; and

FIG. 2 is a view taken in the direction of arrow II of FIG. 1.

SPECIFIC DESCRIPTION As shown in FIGS. 1 and 2 a folding bar 10 is dis placeable from a solid-line starting position to a dotdash line end position to form a fold in a workpiece 20. This fold underlies a workpiece guide 21 which forms part of the feed bar of a sewing machine 50.

The folding element 10 comprises a flat bar or strip 11 on which is provided an array of parallel needles 12. This bar II is carried on a pair of arms 15 pivoted on a support 43 and operated by the piston rod 14 of a pneumatic cylinder 13. Thus when the piston rod 14 is extended the needles 14 force a fold of the workpiece 20 between the bar 21 and the table 22 of the sewing machine 50 so as to allow the stitching needle 51 of this machine to form a line of stitching in the fold.

The advance bar 21 can be raised and lowered as shown by arrow A at right angles to the plane of movement of the folding element 10 so as to be able to clamp the fold snugly against the surface 22.

In accordance with the present invention the support plate 40 extends at an angle of approximately to the surface 22. This plate 40 is planar and formed with a slot 41 provided on each side with lip-forming springs 42 formed as a single loop of a coil spring so that the fold pushed through the slot 41 is held between these lips 42.

A marking lamp is provided which directs a beam of light directly at the slot 41 at the position where the needles 12 will engage and fold the fabric workpiece 20. Thus the workpiece is held on the table 40 in such a manner that the position where the dart is to be formed lies exactly at the beam of light from the lamp 30. Then the cylinder 13 is actuated to form the fold and the dart is stitched in a manner known per se. Since the goods 20 are arranged with their right side 23 out it is possible to position the dart within the pattern at an inconspicuous location.

Once the stitching operation is started the folding element 10 can be withdrawn. An experienced worker can therefore form darts in fabric workpieces in just several seconds, orienting them perfectly. An operating pedal 18 is provided connected to the cylinder 13 for advancing the needles 12 into the fold slowly so as to position this fold under the holding bar 21 and to withdraw it rapidly. In addition the supports 43 are mounted on an arm 44 pivotal about a vertical axis A so as to allow the entire fold-forming assembly to be displaced out of the way.

Although the surface 40 illustrated in FIGS. 1 and 2 is shown to be upright or substantially vertical it is possible to have this table perfectly horizontal and provide the sewing machine 40 underneath it with the surface 22 vertical.

1 claim:

1. A method of feeding a workpiece to the stitching station of a sewing machine having a flatbed under said station, said method comprising the steps of:

laying said workpiece right side out on a flat table, ad-

jacent and transverse to the plane of said bed; thereafter positioning a predetermined location on said workpiece over an aperture in said table in line with said bed; and

pushing a fold of said workpiece at said location through said aperture along said bed to said station.

2. An apparatus for feeding a workpiece to the stitching station of a sewing machine having at said station a flat bed, said apparatus comprising:

a flat support table adjacent and transverse to the plane of said bed, said table being formed with an aperture in line with said bed;

a folding element reciprocal through said aperture to said station; and

means for reciprocating said element to push a fold of said workpiece through said aperture in to said station.

3. The apparatus defined in claim 2 wherein said table is a slotted plate.

4. The apparatus defined in claim 3 wherein said plate is provided at the edges of said aperture with elastic lips.

5. The apparatus defined in claim 4 wherein said lips are constituted by at least one coil spring.

6. The apparatus defined in claim 2 wherein said folding element comprises a reciprocal bar and an array of parallel needles arranged in a row on said bar and directed toward said station.

7. The apparatus defined in claim 2 wherein said sewing machine is a dart-forming sewing machine.

' l I= l

Claims

1. A method of feeding a workpiece to the stitching station of a sewing machine having a flat bed under said station, said method comprising the steps of: laying said workpiece right side out on a flat table adjacent and transverse to the plane of said bed; thereafter positioning a predetermined location on said workpiece over an aperture in said table in line with said bed; and pushing a fold of said workpiece at said location through said aperture along said bed to said station.

2. An apparatus for feeding a workpiece to the stitching station of a sewing machine having at said station a flat bed, said apparatus comprising: a flat support table adjacent and transverse to the plane of said bed, said table being formed with an aperture in line with said bed; a folding element reciprocal through said aperture to said station; and means for reciprocating said element to push a fold of said workpiece through said aperture in to said station.

3. The apparatus defined in claim 2 wherein said table is a slotted plate.

7. The apparatus defined in claim 2 wherein said table is a plate extending at an angle between 70* and 80* to said bed.

8. The apparatus defined in claim 2, further comprising means for displacing said table and said element away from adjacent said bed.

9. The apparatus defined in claim 2, further comprising a lamp having a beam directed at said aperture.

10. The apparatus defined in claim 2 wherein said sewing machine is a dart-forming sewing machine.