GB2187212A - Device for sewing materials with nap or pile - Google Patents

Abstract

A carrier 8 is formed so as to fit conveniently (as for example on the safety cover 14) on an existing swing needle or blind stitching machine, at the same time housing and guiding an endless flat belt 7 under part circular safety guards 12 (which can be removed to permit changing of the belt 7) and provide a method of slack adjustment. The belt 7 forms a cushion between the under support (and transport) elements of the machine and the material being sewn which will travel at the same velocity as the material whilst remaining in position on the sewing machine. <IMAGE>

Description

SPECIFICATION Deviceforsewing materials with nap or pile This invention relates to machines for sewing materials with nap or pile.

It is well known that sewing machines with straight line movement having their needles passing through both thicknesses of materials to be sewn, leave the stitching with an unacceptable appearance. In order to tryto overcome this drawback, "swing" needle or blind stitching machines may be used whereby the needle is caused to move in an arc to penetrate fully the upperlayerand only partiallypenetratethe under layer so forming a stitch which is hidden from the side most often seen, as for example, in curtains and upholstery. Even with this method the combination of feed mechanism and under support (e.g. rib and feed platens) cause a crushing of the pile leaving a mark in the material which cannot be completely removed.The latter effect can be overcome by placing a strip of material between the under supporting elements and the fabric being sewn and causing both to pass through the machine at the same time. Usually such strips are short and have to be continually reinserted, a time consuming and non-productive activity. A known modification to blind stitching machines uses an endless belt of material passing overfour rollers mounted on a frame fitted after modification to an existing machine but still with inherent problems.

According to the present invention a simple belt of conventional "flat" type, having athin rectangular cross section is formed into a small continuous ring and is mounted in a carrier in such a manner as to allowthe beltto transportthe fabric overthe under support in a smooth continuous motion. Such a system needs little modification to existing machines and provides blemish free output.

A specific embodiment of the invention will now be described by way of example with reference to the following drawings in which: Figure 1 shows in perspective the sewing area of a blind stitching machine with the invention shown in "ghosted" outline.

Figure 2 shows a section across the invention and the relationship to the carrier Figure3shows a cross section of the invention with covers removed and belt in process of being changed.

Referring to the drawings the invention comprises a belt 7 lightly constrained to travel in a substantially circular path tangential and perpendicularto the line of travel of the sewn material by a carrier 8.

In the embodiment of the invention illustrated the blind stitching machine 1 has the safety cover 14 removed, fitted with the carrier 8 complete with belt 7 cover 12 adjuster 16 etc. and refitted. As the carrier 8 mounted on the safety cover 14 is refitted to the machine 1 the belt 7 is caused to lie overthe under support elements (rib 4feed platen 3 and 3a or roller 3b and between these and the feed foot 2 in the path 5 of travel of the material being sewn.

Shoulders 9 one on each side of the carrier8 constrain the belt from sideways movement in the plane of fabric movement 10. Slots 11 formed in the shoulders 9 house transparent safety covers 12 which can be slid out of the slots 11 in orderto remove and replace the belt 7. In a specific form of the invention the carrier 8 has integrally extended from the shoulders 9 a wing 13 on each side to act as a stiffener to its construction and prevent tilting of the carrier when mounted upon the machine safety cover 14.

In orderto retain the carrier 8 in the correct position on the cover 14 and prevent rotation around it, fasteners 15 are provided in the form of screws or rivets for example.

Since the circumferential length of the inside of the belt 7 must be slightly largerthan the cross sectional perimeter of the carrier 8 in orderto permit replacement of the belt 7 it follows that adjustment should be provided to take up some of the slackthus formed. In the case illustrated a pin 16 is equipped with locking means e.g. a nut 17 and constrained within a slot 18 sothat pin 16 may be moved outwardly substantially radically with respect to the centre of the cover 14. By choice otherformsof adjustment,asforexample,acam ring (mounted on the carrier 8) (not shown) may be used instead or additionally.

From the foregoing description it can be seen that a device according to the present invention occupies little volume upon and needs minimal modification to an existing blind stitching machinewhilst providing a method of producing blemish free sewing on piled or napped materials at commercially acceptable production rates.

1. An element for a sewing machine comprising a flat section endless belt formed into a ring and constrained to move in a substantially circular path under and in direct contact with the material whilst it is being sewn.

2. Acarrierforming a mounting and guide means for an endless belt to move as described in 1.

3. Acarrierwith guidewaysforming sideways restraint to the belt as described in 1 and 2.

4. Acarrierwherein provision is made to mount in an easily detachable manner safety covers over the belt as in 1 in order to prevent possible contact with the moving belt.

5. A carrier as in 2,3 and 4wherein provision is made to extend the near circulartrack of the belt as in 1 in order to remove some slack and provide slight tension to it.

6. A carrier and belt system as described in any preceding claims so formed asto permitthesystem to fit readily on to existing swing needle or blind stitching sewing machines.

New claims or amendments to claims filed on 9th March 1987.

Superseded claims N.A.

New or amended claims:

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (7)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Deviceforsewing materials with nap or pile This invention relates to machines for sewing materials with nap or pile. It is well known that sewing machines with straight line movement having their needles passing through both thicknesses of materials to be sewn, leave the stitching with an unacceptable appearance. In order to tryto overcome this drawback, "swing" needle or blind stitching machines may be used whereby the needle is caused to move in an arc to penetrate fully the upperlayerand only partiallypenetratethe under layer so forming a stitch which is hidden from the side most often seen, as for example, in curtains and upholstery. Even with this method the combination of feed mechanism and under support (e.g. rib and feed platens) cause a crushing of the pile leaving a mark in the material which cannot be completely removed.The latter effect can be overcome by placing a strip of material between the under supporting elements and the fabric being sewn and causing both to pass through the machine at the same time. Usually such strips are short and have to be continually reinserted, a time consuming and non-productive activity. A known modification to blind stitching machines uses an endless belt of material passing overfour rollers mounted on a frame fitted after modification to an existing machine but still with inherent problems. According to the present invention a simple belt of conventional "flat" type, having athin rectangular cross section is formed into a small continuous ring and is mounted in a carrier in such a manner as to allowthe beltto transportthe fabric overthe under support in a smooth continuous motion. Such a system needs little modification to existing machines and provides blemish free output. A specific embodiment of the invention will now be described by way of example with reference to the following drawings in which: Figure 1 shows in perspective the sewing area of a blind stitching machine with the invention shown in "ghosted" outline. Figure 2 shows a section across the invention and the relationship to the carrier Figure3shows a cross section of the invention with covers removed and belt in process of being changed. Referring to the drawings the invention comprises a belt 7 lightly constrained to travel in a substantially circular path tangential and perpendicularto the line of travel of the sewn material by a carrier 8. In the embodiment of the invention illustrated the blind stitching machine 1 has the safety cover 14 removed, fitted with the carrier 8 complete with belt 7 cover 12 adjuster 16 etc. and refitted. As the carrier 8 mounted on the safety cover 14 is refitted to the machine 1 the belt 7 is caused to lie overthe under support elements (rib 4feed platen 3 and 3a or roller 3b and between these and the feed foot 2 in the path 5 of travel of the material being sewn. Shoulders 9 one on each side of the carrier8 constrain the belt from sideways movement in the plane of fabric movement 10. Slots 11 formed in the shoulders 9 house transparent safety covers 12 which can be slid out of the slots 11 in orderto remove and replace the belt 7. In a specific form of the invention the carrier 8 has integrally extended from the shoulders 9 a wing 13 on each side to act as a stiffener to its construction and prevent tilting of the carrier when mounted upon the machine safety cover 14. In orderto retain the carrier 8 in the correct position on the cover 14 and prevent rotation around it, fasteners 15 are provided in the form of screws or rivets for example. Since the circumferential length of the inside of the belt 7 must be slightly largerthan the cross sectional perimeter of the carrier 8 in orderto permit replacement of the belt 7 it follows that adjustment should be provided to take up some of the slackthus formed. In the case illustrated a pin 16 is equipped with locking means e.g. a nut 17 and constrained within a slot 18 sothat pin 16 may be moved outwardly substantially radically with respect to the centre of the cover 14. By choice otherformsof adjustment,asforexample,acam ring (mounted on the carrier 8) (not shown) may be used instead or additionally. From the foregoing description it can be seen that a device according to the present invention occupies little volume upon and needs minimal modification to an existing blind stitching machinewhilst providing a method of producing blemish free sewing on piled or napped materials at commercially acceptable production rates. CLAIMS

1. An element for a sewing machine comprising a flat section endless belt formed into a ring and constrained to move in a substantially circular path under and in direct contact with the material whilst it is being sewn.

2. Acarrierforming a mounting and guide means for an endless belt to move as described in 1.

3. Acarrierwith guidewaysforming sideways restraint to the belt as described in 1 and 2.

4. Acarrierwherein provision is made to mount in an easily detachable manner safety covers over the belt as in 1 in order to prevent possible contact with the moving belt.

5. A carrier as in 2,3 and 4wherein provision is made to extend the near circulartrack of the belt as in 1 in order to remove some slack and provide slight tension to it.

6. A carrier and belt system as described in any preceding claims so formed asto permitthesystem to fit readily on to existing swing needle or blind stitching sewing machines.

New claims or amendments to claims filed on 9th March 1987.

Superseded claims N.A.

New or amended claims:

7. A belt like element and its carrier as described in claims 1-6 and broadly as shown in the accompanying drawings.