GB2442894A - Sewing machine quick release jig - Google Patents

Abstract

Disclosed is a quick release jig mechanism for locating stitching templates of various sizes and shapes, and securing the templates accurately to a sewing machine bed, in preparation for final assembly stitching of various items and belts to automobile air bags. The mechanism preferably comprises a base member 7 attached to each template by screws through holes 8, and an engagement member 13 secured to the sewing machine bed by screws through holes 14. Preferably, latch 9 is secured by a screw 10 to the upper face of the base 7, and dowel 17 captive within a rectangular section key 16, holds member 7 in position on member 13, and dowels 20 provide for accurate relative location of the members. Key 16 is preferably spring loaded and member 7 (including the template) can be released from member 13 by depressing the end of key 16 to disengage dowel 17 from latch 9. Another member 7 with a different template can then be accurately located on the sewing machine, giving quick production changeover.

Description

IMPROVEMENTS IN OR RELATING TO SEWING MACHINE

JIGS AND THE LIKE.

Present day automobiles are fitted with safety Air Bags' and have been for many years, compliant with strict health and safety regulations and legislation presently in force.

By reason of the vast numbers of models manufactured within the automotive industry world wide, it is necessary to have hundreds, if not thousands of various shapes and sizes, which satisfy the design criteria of both the model type of automobile and its manufacture, other than a small number of large automobile manufactures, who produce their own Air -Bags' whilst the remainder sub-contract the manufacture and supply.

On final assembly of the' Air -Bags' it is necessary to attach various reinforcement pieces by stitching in specified positions, in order to strengthen the bag in key areas.

Straps also of varying design require stitching in position.

In the main sewing machines used for this stitching method will have computer numerical control (C.N.C.) which provides both speed and accuracy. However to achieve this it is found necessary to have accurate stitching templates, which Locate on the sewing machine and require to be rigid and remain in position whilst stitching takes place. The templates have holes' and slots' in specified positions where the actual sewing takes place.

One of the present conventional methods used, is to provide templates in varying shapes and sizes, and for this description only is manufactured from a semi -ridged plastic of three millimetres thickness. Attached at a specified position on the template is an engagement member (usually on the perimeter), and secured by screw isteners.

A mating engagement member is attached and remains in permanent position. to the machine, when the said template is positioned on the uppermost side of the air bag on the machine bed., as the two engagement members are engaged and located together.

The Air -Bag' having already been placed in position with the various reinforcement sections and straps, in readiness for stitching permanently in position.

When the quantity of Air-Bags' corresponding to the production/design determined by the template are completed, then it becomes necessary for the template to be changed, ready for completion of the next design required within the production schedule. Both the removal of the engagement members and template, and the said re-fitting of the template (although each template is fitted with an engagement member), it is time consuming for this change over to take place. Taking some fifteen to twenty minutes creating loss in production time.

The change over also involves removal of certain parts on the sewing machine for accessibility for template change; the time loss would be significant if template changes take place frequently within production runs.

Bt way of the following description and drawings the invention seeks to improve on this time loss problem.

SUMMARY OF THE INVENTION.

A quick release jig used for locating templates of varying sizes and shapes, and securing the said template easily and accurately to a sewing machine, in readiness for final assembly stitching of various items to Air -Bags' fitted to automobiles.

Fig. I. Assembly drawing of the device (Plan view) Fig.2. Plan elevation and end view.

Fig.3. Plan, elevation and sectional end view.

Fig.4. Plan and elevation.

Fig.5. Plan view of top plate.

Item 6 Fig 1 is the device/tooling aid, which will be secured by screw fastenings to each and every template (the template not shown) Item 7 Fig' s 1 and 2 shows the main base/housing to be secured to each template, using the eight holes 8.

Item 9 Fig' s 1 and 2 is a small latch secured within the top surface T' by a C/sunk headed screw 10 and aided by a tight -close fit within the parallel groove/recess 11 within the top surface, Fig 2 the thro' slots items 12 Fig' s I and 2 are provided for clearance purposes only on screw head projections on the sewing machine.

Item 13 Fig 3 is an engagement member and secured to the machine by screw fasteners (not shown) using the two holes 14 Fig's I and 3, retaining the member in position on the machine.

A closed end slot' 15 Fig 3 having dimensions compatible with a key item 16 Fig' s 1 and 4.

A Dowel' item 17 Fig' s I and 4 is secured by a light -drive fit within the key 16, (AND FOR THIS DESCRIPTION ONLY IS OF CIRCULAR SECTION).

The recess 18 in the key' 16 Fig 4 is a clearance for the latch item 9 Fig's I and 2.

The secondary recess 19 Fig 4 is for clearance purposes only, on the upper surface of the dowel item 20 Fig 3 (Ref. at the right hand side only).

The dowels items 20 Fig' s I and 3 are used when the engageable member item 13 is positively engaged within the holes 21 within the main base housing item 7 Fig's I and 2.

A compression spring item 22 Fig 1 is fitted on assembly between the key item 16 within the groove 15 Fig's I and 3 at the closed end of the slot' 15., the spring is of a compression type with a specified rating, both the key 16 and the spring 22 are retained in position by a top' mounting plate 23 Fig 5.

The top plate item 23 is secured in position using the four counter -sunk holes 24 within the plate, using four C/sunk screws within the internal threaded holes 25 Fig s 1 and 3.

To ensure that the top plate item 23 when screwed down in position, does not clamp the key' preventing movement of the key 16 Fig I., denoted by the arrow x. This is achieved by ensuring that the dimension of the depth of slot' 15 Fig 3, represented by the dimension D', is greater than the height of the key item 16 Fig 4, when in position on final assembly.

This is achieved by ensuring that the slot 26 Fig 5 having a width represented by the divension W' is compatible with the dowel diameter item 17 Fig's 1 and 4 the slot 26 Fig 5 will restrict and control movement (forward and backwards) of the key 16 Fig 1.

Suminarising, the aforesaid components having been assembled, the mode of operation for use, is as follows: -The engageable member item 13 Fig 3 will be secured in a specified position on the sewing machine using the two holes 14 and screw fasteners, the larger holes 27 allow the head of the socket screw to pass through to the underside base of the slot 28 Fig 3 at the rear of the block, and engage within threaded holes in the machine bed. The larger holes 29 Fig 5 allow access for a hand tool (for this description only) an allan key, for use within the hexagon head of the screw below (not shown) The main housing item 7 Fig's 1 and 2 having been secured to all templates, will allow the selected templates to be presented in position on the machine, and the latch item 9 Fig' s I and 2 will engage within the recess 30 Fig' s I and 3 causing the key to move forward (shown abbreviated in Fig 1) against the resistance of the compression spring item 22 Fig I and held captive in position by the latch item 9 and dowel 17 Fig I, accurately located in position, engagedly together by the dowel locations items 20 Fig's land 3.

To release the template from the machine is as follows, when the outer end' of the key item 16 Fig 1 is pushed forward (shown abbreviated in Fig 1) against the spring pressure, allowing the template to be withdrawn., this operation will take less than thirty seconds.

Claims (4)

1. A quick release jig, used for locating stitching templates of various sizes and shapes, and temporally securing the templates to a sewing machine in readiness for final assembly stitching of various items and straps, to Air-Bags' fitted to AutomobiLes.

2. A quick release jig, as claimed in claim 1, having in the first part a base member attached by screw fasteners to the said templates, a mating secondary member is secured to a sewing machine, a latch secured to the upper top surface of the said base member, will temporally retain in position the first and secondary members by a circular dowel captive within a rectangular key', housed within the secondary member, and retain the first and secondary members in position, by the said dowel restricting movement of the said latch, aided by a compression spring acting at one end of the said key'.

3. A quick release jig, as claimed in claim 2, where controlled linear guide movement of the first member relative to the secondary member is achieved by two circular dowels secured within the said secondary member, and two corresponding compatible holes within the outer section of the said first member.

4. A quick release jig, as claimed in claims 1, 2 and 3 and substantially as herein before described with reference to the accompany drawings.