GB2341134A

GB2341134A - A press assembly

Info

Publication number: GB2341134A
Application number: GB9819185A
Authority: GB
Inventors: John Leslie Broad
Original assignee: MG Rover Group Ltd
Current assignee: MG Rover Group Ltd
Priority date: 1998-09-04
Filing date: 1998-09-04
Publication date: 2000-03-08
Also published as: GB9819185D0

Abstract

A press assembly 105 is disclosed having a location piercing means 120, 121 attached to a fixed support 106 and a ram 107. The location piercing means includes a punch 112 engageable with an aperture in a die 113 and a location pin 114 locatable in an aperture in an bush 115. The location forming means 120, 121 accurately forms a location aperture in sheet material 104 as it is fed into the power press. This obviates the need for the dies used in the power press to include means for producing such location holes or for guiding the material.

Description

2341134 A Press Assembly This invention relates to a power press and in

particular to a power press for use with a progression type of press tool having a number of forming, cutting and piercing stations.

It is well known to provide a power press with a means for feeding sheet material to the press and ineans to accurately control the movement of the sheet material through a multi-station or progression press tool.

Such prior art power presses normally have a moveable ram and a stationary bed to support the press tool. The press tool includes not only the required shape and configuration to form the component from sheet material but also includes additional operations to produce one or more location holes used to accurately locate the sheet material as it progresses through the press tool.

It is a disadvantage with such an arrangement that every press tool has to have a means to produce such location holes so as to ensure that the material is correctly located and this increases both the size and cost of manufacture of such press tools.

It is an object of this invention to overcome the problems associated with the prior art.

According to the invention there is provided a press assembly having a power press and a progression press tool, the power press having a fixed support and a ram moveable with respect to the fixed support defining an aperture into which the progression press tool is secured, the press tool having upper and lower dies defining a number of stations through which sheet material is progressed to form an article, wherein the power press has one or more location pins attached thereto for engagement with apertures in the material being formed to locate the material accurately between the dies and a location piercing means to produce said apertures.

Each of said apertures may be formed in the material by piercing with a punch supported by the ram for co-operation with a die supported by the fixed support.

The punch and die used to pierce the material may be moveable to adjust the location of the apertures in the material.

The location piercing means may include one or more adjustable guide rails.

The location piercing means may include at least one location pin and one location bush to accurately position the material.

The position of the location pin and the position of the location bush in the location piercing means may be adjustable to allow them to be aligned with the apertures in the material.

The punch may be releasably secured to the ram of the power press so as to allow punches of different shape and size to be easily attached to the ram.

The die may be releasably secured to the fixed support of the power press so as to allow dies of different shape and size to be easily attached to the fixed support.

The location pin may be releasably attached to the ram so as to allow location pins of different shape and size to be easily attached to the ram.

The location pin bush may be releasably attached to the fixed support so as to allow location pin bushes of different shape and size to be easily attached to the fixed support.

The invention will now be described by way of example with reference to the accompanying drawing of which:- Fig. 1 is a pictorial representation of a prior art press assembly;

Fig.2 is a pictorial representation of a press assembly according to this invention; Fig.3 is a plan view of a lower die forming part of the prior art press assembly shown in Fig. 1;

Fig.4 is a plan view of a progression tool for use in a press assembly according to this invention; and Fig.5 is a plan view of a location piercing means forming part of this invention.

With particular reference to Figs.1 and 3 there is shown a prior art power press 5 having a fixed support 6 and a moveable ram 7. A progression press tool 40 interposed between the fixed support 6 and the ram 7. The progression press tool 40 having a lower die 9 fitted with guide rails 8 and an upper die (not shown). The power press 5 being arranged to be supplied with sheet material 4 by a sheet metal feeder 10. The lower die 9 having a punch support 13 for co-operation with a punch support 13 for cooperation with a punch (not shown) attached to the upper die to form a location hole in the strip 4 and a location hole 15 used to locate the strip 4 within the guide rails during punching of said location hole. Location apertures 16 are provided within a productive part of the progression tool to locate the sheet material as it progresses through the progression tool.

With particular reference to Figs.2, 4 and 5 there is shown a press assembly 105 having a ram 107 and a fixed support in the form of a bed or bolster 106. The fixed support 106 supports a lower die 109 of a progression tool 140 which includes a.number of forming, cutting and piercing stations used to produce an article from a sheet of metal 104 fed to the press assembly 105 by a sheet metal feeder 110. The progression tool 140 also includes an upper die (not shown).

A location piercing means is attached to the fixed support 106 and the ram 107 on the side of the power press from which the sheet material 104 is fed into the progression tool 140. The location piercing means comprises of an upper platen 120 supporting a piercing punch 112 and a location pin 114 and a lower platen 121 supporting a punch support block 113, a location aperture block 115 and two spaced apart guide rails 108.

The guide rails 108 are moveable in the direction X-X as shown on Fig.5 so as to accommodate difierent widths of sheet material 104.

The piercing punch 112 and the punch support block or die 113 are moveable both longitudinally along the platens 120, 121 and transversely across the platens 120, 121. The location pin 114 and its co-operating location bush 115 are also moveable longitudinally and transversely with respect to the platens 120, 121.

A method of accurately indexing the punch is provided in the form of a servo motor 111 to move the punch support block 113 longitudinally along the platen 121.

The punch 112 and the punch die block 113 are fitted in recesses (not shown) in the platen 120 and 121. Both the punch 112 and the punch die block 113 are releasably secured to the platens 120, 121 so that they may be easily changed and replaced for alternative punch and punch support means of different shape and size. Similarly, the location pin 114 and the location aperture block 115 are releasably secured to the platens 120, 121 so that they can be easily replaced by components of different shape and size corresponding to the location apertures made by the punch 112.

Both the punch and the die and the guide pin and the guide pin bush must be indexed to the same position to ensure that they are correctly aligned.

The location pin 114 is used to accurately position the material between the dies of the progression tool 140.

As can be seen by comparing Fig.4 with Fig.3, the lower die 109 progression tool is considerably smaller than the lower die 9 of the progression tool 40. This is because all of the hardware required to produce the location apertures in the sheet material is attached to the platens 120, 121 forming the location piercing means. This enables the progression tool 140 to be much smaller and therefore both lighter and cheaper to manufacture than the prior- art press tool 40.

By using a press assembly according to the invention, a simpIffied press tool without the facility to produce location apertures can be employed and so the means to produce said location apertures only has to be produced once. If the size or position of the location apertures demanded by a particular press tool need to be altered, the location piercing means is fully adjustable and both the punch 112 and the location pin 114 are easily replaced by corresponding components of different shape and size.

It will therefore be appreciated that the location piercing pin, piercing bush, guide pin, guide pin bush and guide rails to guide the material are all part of the power press and do not need to be included in any tool used in the power press.

Claims

A press assembly having a power press and a progression press tool, the power press having a fixed support and a ram moveable with respect to the fixed support defining an aperture into which the progression press tool is secured, the press tool having upper and lower dies defining a number of stations through which sheet material is progressed to form an article, wherein the power press has one or more location pins attached thereto for engagement with apertures in the material being formed to locate the material accurately between the dies and a location piercing means to produce said apertures.
2. A press assembly as claimed in Claim 1 in which each of said apertures is formed in the material by piercing with a punch supported by the ram for co-operation with a die supported by the fixed support.
3. A press assembly as claimed in Claim 2 in which the punch and die used to pierce the material are moveable to adjust the location of the apertures in the material.
4. A press assembly as claimed in any of Claims 1 to 3 in which the location piercing means includes one or more adjustable guide rails.
5. A press assembly as claimed in Claim 2 or in Claim 3 when dependent upon Claim 2 in which the location piercing means includes at lehst one location pin and one location bush to accurately position the material.
6. A press assembly as claimed in Claim 5 in the position of the location pin and the-position of the location bush in the location piercing means are adjustable to allow them to be aligned with the apertures in the material.
7. A press assembly as claimed in Claim 2 or in Claim 3 in which the punch is releasably secured to the ram of the power press so as to allow punches of different shape and size to be easily attached to the ram.
8. A press assembly as claimed in Claim 2 or in Claim 3 in which the die is releasably secured to the fixed support of the power press so as to allow dies of different shape and size to be easily attached to the fixed support.
9. A press assembly as claimed in Claim 5 or in Claim 6 in which the location pin is releasably attached to the ram so as to allow location pins of different shape and size to be easily attached to the ram.
10. A press assembly as claimed in Claim 5 or in Claim 6 in which the 1 location pin bush is releasably attached to the fixed support so as to allow location pin bushes of different shape and size to be easily attached to the fixed support.
11. A press assembly substantially as described herein with reference to the accompanying dra-,.ving.