Tool-holder for a press

Abstract: A tool-holder for machine tools, in particular a punch-holder (10) for forging machines utilised for the production of bolts and screws and provided with an oscillating plate (18), is connected to a plate-like support (12) by means of screws (14), and is adjustable on the same by means of eccentrics (16); said plate-like support (12), which bears at least a punch-holder (10), is caused to be interchangeably integral by two or more screws (20) with the oscillating plate (18) of said forging machine.

Description: The present invention relates to a tool-holder for forging machines employed for the production of bolts and screws and provided with an oscillating plate according to the preamble of claim 1 (see e.g. GB-A-413 132). As is known, in the field of the production of screws, rivets and the like, obtained by cold deformation of wire lengths, special machines are used that carry out sequentially different working operations starting from a semi-finished product, constituted precisely by a wire having a suitable section, which unwinds from a skein. In the forging machines of the known art, one of the basic problem is associated to the type of product to be obtained in terms of size, or the necessity of systematically replacing the forging members whenever the type of artefact to be made changes. Raw screws or rivets or like small items are in fact obtained on the forging machines by means of special forging tools, in particular by punches caused to be integral with a special support and to co-operate with a matrix restraining the wire that constitutes the semi-finished product. Therefore, whenever the product to be obtained changes, it is necessary to replace said punches and the related support with other ones having suitable shape or size, which involves difficult adjustments, with ensuing delays in the time of preparation of the machine. Object of this invention is to obviate the aforesaid drawback. More particularly, object of this invention is to provide a tool-holder for forging machines employed for the production of bolts and screws, suitable to be easily installed and replaced, with no need for complex adjustments. A further object of the invention is to provide users with a tool-holder as defined above, such as to ensure a high level of resistance and reliability in the time, and also such as to be easily and economically realised. These and still other objects are achieved by the tool-holder according to claim 1. The construction and functional characteristics of the tool-holder of this invention will be better stressed by the following description, wherein reference is made to the attached drawings which represent a non limiting preferred embodiment of the same, and wherein: Figure 1 schematically shows a front view of one embodiment of the tool-holder of this invention; Figure 2 schematically shows a longitudinal section of the same tool-holder. With reference to the above figures, the tool-holder of this invention for forging machines employed for the production of bolts and screws, is indicated as a whole by 10 and comprises a punch-holder connected to a plate-like support 12, known in itself, by means of a couple of screws 14; on said support, the punch-holder is adjustable by means of a system of eccentrics 16, also known. According to the invention, the plate-like support 12 is adapted to be fixed to the oscillating plate 18, making part of the forging machine (not shown), by means of two or more further screws 20; said plate 18 forms in the upper part a protruding extension 18' suitable to strike, during its oscillatory movement, conventional stop members 22. In the preferred embodiment of the figures, as can be especially seen in Figure 1, two coupled punch-holders 10 are connected to the plate-like support 12, because of the oscillatory movement of plate 18 which leads alternatively either of said punches to operate on the wire to realise the small items, namely screws, rivets and the like. Said wire, which unwinds from a corresponding skein, is fed near the punch-holders 10 by special devices, not included in the invention, comprising extraction pins 24, 24' with the related springs 26 and subjected to working starting from the ram, indicated by 28, of the forging machine, co-operating with a tang 30 integral with the oscillating plate 18. The plate-like support 12 is advantageously coupled to the latter in a precise and univocal manner, through reference and strike means 32, constituted by one or more keys or the like. If the working should be changed, changing therefore also the forging punches, it suffices to provide to replacing the plate-like support 12 bearing the punch-holders 10, with another similar support already assembled and provided with suitable seats for housing and restraining differently shaped and/or sized punches, to be used in the case in point. The operation is particularly quick and easy for the operator, as there is only needed the prior removal of said plate-like support 12, on prior loosening and unthreading of screws 20 and the subsequent installation and connection of another complementary support by the same blocking means. As the replacement of said support 12 does not cause any changes in the operating whole of the forging machine, as it does not affect the working of the same, the result is achieved of markedly accelerating tooling times, especially considering that the punch or punches are substantially separate or external relatively to the operating whole of the machine and do not require therefore supplementary adjustments or regulations of other devices. As can be understood from the above, the advantages of the invention are obvious. The tool-holder of the present invention allows to markedly reduce the machine-tooling time and excludes the need of adjustment operations on the tools or devices whose working is related to the same.

Claims: A tool-holder for forging machines employed for the production of bolts and screws and provided with an oscillating plate (18), comprising at least one punch holder (10) connected to a plate-like support (12) by means of screws (14) and being adjustable on the same by means of eccentrics (16), characterised in that said plate-like support (12) bearing said at least one punch-holder (10) is adapted to be interchangeably fixed by means of two or more further screws (20) to the oscillating plate (18) of said forging machine. The tool-holder according to claim 1, characterised in that it has one or more obligated strike and centring means (32) for coupling with the oscillating plate (18). The tool-holder according to claim 2, characterised in that said strike and centring means (32) are obtained on the plate-like support (12) and are adapted to engage with said oscillating plate (18). The tool-holder according to claim 2 or claim 3, characterised in that said obligated strike and centring means (32) are constituted by at least a key.

Inventors: GARLASCHI EUFEMIA, GARLASCHI, EUFEMIA
Applicants: CARLO SALVI & C S R L, CARLO SALVI & C. S.R.L.
Application year: 1998
Main classification: B21J13
IPC codes: B21J13, B21K1