GB2148173A

GB2148173A - Copying device for shaping blanks in presses and tools for presses

Info

Publication number: GB2148173A
Application number: GB08328842A
Authority: GB
Inventors: Charles Henry Clews
Original assignee: Individual
Current assignee: Individual
Priority date: 1983-10-28
Filing date: 1983-10-28
Publication date: 1985-05-30
Also published as: GB8328842D0; GB2148173B

Abstract

A copying device for shaping blanks that can be quickly attached to many types of mechanical press comprises a holder 2 for carrying a blank 1 that can be moved in two directions at right angles on slides 4, 5 to position any part of the blank over a die 10 with a reciprocable punch above the blank. A fixed template 16 has small holes disposed so that when the blank holder 2 is moved by means of a plunger 18 mounted thereon and the plunger is caused to engage the holes in succession, the blank 1 is located over the die 10 in corresponding positions so that a pattern 22 determined by the template and by the shape of the punch and die is cut. Alternatively the sensor engages a profiled edge of a template. The punch and die are latched in position by spring catches enabling them to be readily replaced by other shapes. <IMAGE>

Description

SPECIFICATION Copying device for shaping blanks in presses and tools for presses This invention relates to a copying device for fitting to a hand or open fronted mechanical press for producing punched or notched blanks from simple templates. The invention further relates to tools for such presses.

One object of the invention is to provide such a device that can be set up, even in a few minutes, on a press primarily for short run work, preproduction and prototype work.

According to the invention a copying device for shaping blanks in presses comprises a blank holder mounted for movement in two directions at right angles while carrying a blank between a punch and a die mounted on a common fixed axis whereby the blank can be punched at any location thereon within the range of movement of the blank, means supporting a stationary template and a sensing member carried by the blank holder and arranged to engage holes in or edges of the template located according to the location of points on the blank to be punched, whereby the sensing member can be used to move the blank holder to positions in succession for the punch to cut a shape in the blank corresponding to the shape of the template.Very conveniently the template may be formed with simple holes located according to the locations on the blank to be punched and the sensing member is a spring loaded plunger arranged to be pressed down into each of the holes in succession so as to hold the blank stationary in positions corresponding to the positions of the holes and at which the punch is operated.

Although the template may be formed with simple holes the actual pattern produced on the blank depends also on the shapes of the punch and die.

It is therefore very advantageous for the punch and die to be quickly changed when holes of different shapes are to be punched in the blank. This can be very conveniently achieved by arranging the punch and die to be latched in holders by spring loaded means enabling them to be readily inserted in and withdrawn from the holders.

According to a further aspect of the invention therefore a punch and die assembly for use in a copying or other mechanical press comprises holders into which the punch and die are respectively inserted by axial movement into passages in the holders and spring loaded means whereby the punch and die are latched in their holders, the spring loaded means being arranged to yield when the punch and die are withdrawn from their holders for quick replacement.

In order that the invention may be clearly understood and readily carried into effect a press comprising a copying device for shaping blanks will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a front elevation of the copying device; Figure 2 is a plan of the copying device of Figure 1; Figure 3 is a plan of a die holder; Figure 4 is a vertical section through the die holder of Figure 3; and Figure 5 is a vertical section through a punch holder.

Referring to Figures I and 2 a blank 1 is clamped along one edge between a blank holder 2 and a clamp 3. The blank holder 2 is mounted to move in two directions at right angles along two pairs of rod or roller slides 4, 5. The pair of slides 4 project through a portion of the blank holder 2 from a sup port 6 mounted to move transversely along a frame member 7 which also comprises sides 8 carrying the transverse slides 5 which extend through a further portion of the blank holder 2. Thus, the blank can be moved to any position within its area relatively to the axis of a punch 9 and die 10.

The frame 7, 8 is completed by a further transverse member 11 and is mounted on a base 12 supported by a bolster 13 fixed to a press bed 14.

The die 10 is mounted in a die holder 15 fixed to the bolster 13, these parts being shown diagrammatically in Figures I and 2 and described in detail below with reference to Figures 3 to 5.

The punch 9 is caused to punch the blank 1 in a sequence of operations between each of which the blank 1 is moved to a new position by manual movement of the blank holder 2 as determined by a template 16 fixed to the base 12. Each position is located by the registering of a pin 17 at the end of a plunger 18 with an appropriate one of the holes in the template 16. The plunger 18 is vertically guided in a bush 19 at the free end of a cantilever member 20 adjustably mounted on the blank holder 2. To insert the pin 17 into a selected hole in the template 16, the plunger 18 is depressed against the action of a spring 21. Immediately the punch 9 has operated the plunger is released.

In the illustrated example a cross is represented by the holes in the template but the outcome of the operation is an uninterrupted aperture 22 in the blank in the shape of a cross with rectangular corners. This is because the punch 9 is square and of a dimension such that after each punching action the next will extend the hole made by the previous one. Thus, the pitch of the holes in the template is made slightly less than the length of the side of the square punch. When a transverse row of punched holes is to be made it is advantageous to lock the blank holder on the slides 4, and when a perpendicular row is to be punched to lock the carrier on the transverse slides 5.

It will be appreciated that while using the simple form of template for use with the plunger 18, a variety of different types of cuts can be obtained by changinrj the punch and die. Therefore, a very important feature of the press consists in providing means as shown in Figures 3 to 5 for rapidly changing the die and punch. As shown in Figures 3 and 4, the die 10 is simply pushed into a bore in the die holder 15 as far as a shoulder 23. One side of the die, however, has a flat face 24 which is retained in a set position by a detachable locating plate 25. In this position a spring loaded ball 26 can enter a notch in the side of the die which nevertheless can readily be pulled out of the bore for replacement by another.Similarly the punch 9 is retained in a punch holder 27 by a spring loaded ball 28, a locating plate 29 being provided to hold the punch in the required orientation about its axis.

A polyurethane tube 31 is located beneath the locating plate 30 for stripping the blank 1 from the punch 9 when the punch is withdrawn, thereby keeping both punch and die in place.

The area of the blank is only restricted by the throat depth of the press available. The device may be provided with means for cutting a series of blanks from a strip fed through the device, the holes being punched in the blanks either before or after they are severed from the strip. In some instances, where a fair number of blanks are required, initial holes can be punched that are all the same size and these are then modified by using larger round or shaped punches with pilots In larger versions of the blank copying device, the blanks or strips are preferably supported on rollers to provide easier movement of the support along the slides.

In a further modification automatic operation by way of screw drives and stepping motors may be provided under CNC control. Various versions of the device comprising multiple punch heads may be arranged to handle long strips.

In yet another modification, the template of the kind shown in Figure 2 may be replaced by a profiled template for producing curves and radii. In this case the spring 21 is removed from the plunger 18 so that the pin 17 can act as a stylus causing the blank to follow the form of the profile.

Then the punch is caused to reciprocate at a sufficient rate to cut the required shape.

Trial blanks can be produced from a paper or card template.

Claims

1. A copying device for shaping blanks in presses comprising a blank holder mounted for movement in two directions at right angles while carrying a blank between a punch and a die mounted on a common fixed axis whereby the blank can be punched at any location thereon within the range of movement of the blank, means supporting a stationary template and a sensing member carried by the blank holder and arranged to engage holes in or edges of the template located according to the location of points on the blank to be punched, whereby the sensing member can be used to move the blank holder to positions in succession for the punch to cut a shape in the blank corresponding to the shape of the template.

2. A copying device according to claim 1, in which the punch and die are mounted in holders enabling the punch and die to be quickly changed when holes of different shapes are to be punched in the blank.

3. A copying device according to claim 2, in which the punch and die are latched in holders by spring loaded means enabling them to be readily inserted in and withdrawn from the holders.

4. A copying device according to any one of the preceding claims, in which the template is formed with simple holes located according to the locations on the blank to be punched and the sensing member is a spring loaded plunger arranged to be pressed down into each of the holes in succession so as to hold the blank stationary in positions corresponding to the positions of the holes and at which the punch is operated.

4. A copying device according to claim 2, or claim 3, in which the punch is arranged to work through a tubular stripper facilitating stripping the blanks from the punch while keeping both punch and die in place.

5. A copying device according to any one of the preceding claims, in which the template is formed with simple holes located according to the locations on the blank to be punched and the sensing member is a spring loaded plunger arranged to be pressed down into each of the holes in succession so as to hold the blank stationary in positions corresponding to the positions of the holes and at which the punch is operated.

6. A copying device substantially as hereinbefore described with reference to the accompanying drawings.

7. A punch and die assembly for use in a copying or other mechanical press comprising holders into which the punch and die are respectively inserted by axial movement into passages in the holders and spring loaded means whereby the punch and die are latched in their holders, the spring loaded means being arranged to yield when the punch and die are withdrawn from their holders for quick replacement.

8. An assembly according to claim 7, in which each holder is provided with a locating plate for engaging a face on the punch or die shaped to ensure that the punch or die is correctly positioned about its axis for engagement by the spring loaded means.

9. A punch and die assembly substantially as hereinbefore described with reference to Figures 3 to 5 of the accompanying drawings.

Amendments to the claims have been filed, and have the following effect: *(a) Claims 1 to 5 + 7 to 9 above have been deleted or textually amended.

*(b) New or textually amended claims have been filed as follows:-*(c) Claims 6 above have re-num- bered as 5 and their appendancies corrected.

1. A copying device for mounting on a hand or open fronted mechanical press for producing punched or profiled blanks from simple templates, the device comprising a bolster for fixing to a press bed, a base member mounted on the bolster and arranged to support a stationary template thereon, a rectangular frame mounted on the base member and arranged for the template to lie within the ambit of said frame, a blank holder mounted on rod or roller slides located in said frame for movement of the blank holder in two directions at right angles with reference to the axis of a die mounted in a die holder on said bolster outside said frame, a sensing member carried by the blank holder and arranged to engage holes in or edges of the template located according to the location of points on the blank to be punched by a punch when mounted in the press on the axis of the die, whereby the sensing member can be used to move the blank holder to positions in succession for the punch to cut a shape in the blank corresponding to the shape of the template, said die holder as well as a punch holder, to be mounted in the press, being arranged to enable the punch and die to be changed without disturbing the device when holes of different shapes are to be punched in the blank.

2. A copying device according to claim 1, in which the punch and die are latched in holders by spring loaded means enabling them to be readily inserted in and withdrawn from the holders.

3. A copying device according to claim 1, or claim 2, provided with a tubular stripper facilitating stripping the blanks from the punch while keeping both punch and die in place.