The present invention relates to a device for locating, at a determined position on a tool table, such a tool or part thereof as is, at least during the final phase of such location, displaced along the surface of the tool table, the device including mutually cooperating guide means for guiding the tool transversely of its displacement direction, and guide heels for locational determination of the tool.

BACKGROUND ART

Devices for the above-mentioned purpose are previously known in the art, these devices presupposing that the press features a removable press table. In this type of design, the tool (which may weigh as much as between 20 and 40 tonnes) is lifted by means of, for example, a traversing crane, down onto the tool table. Locating the tool on the tool table is effected by upstanding keys in the upper face of the tool table, these keys being, for example, placed in a cruciform pattern. The keys cooperate with keyways in the underside of the tool. Normally, flat keys with a certain edge chamfer are employed.

In order that this method function satisfactorily, it is necessary that the tool depending from the traversing crane is in exactly the right position in relation to the keys before the tool is lowered, so that the keys are accommodated in the keyways provided on the underside of the tool. In order that this be possible in practice, the keys must have a certain edge chamfer and, furthermore, the clearance between the keys and keyways must be relatively large if it is to be at all possible to mount the tool in place. Thus, the level of precision in this method of locating tools is poor, at the same time as the work involved in tool change is time-consuming and laborious.

In such presses as possess a fixed tool table, the above-outlined methodology does not work. Here, use is made instead of a tool carriage which has a table flush with the height of the tool table. The tool is shifted home with the aid of some form of feeding arrangement from the tool

carriage in onto the tool table in the press. In this case, circular pins are employed for locating the tools on the tool table, the pins being inserted down into holes in the tool table. V-shaped notches are provided in the side surfaces of the tool, these notches being intended to cooperate with the cylindrical pins. Thus, the tool is slid along the tool table until two V-shaped notches cooperate each with its cylindrical pin so that thereby advancement of the tool is arrested. Thereafter, the tool is clamped in place on the tool table in the conventional manner.

Locating a tool using cylindrical pins and V-shaped notches suffers from a number of drawbacks. On the one hand, the pins are worn when they are inserted in and removed from the tool table, so that a certain play occurs. On the other hand, there is wear in the contact zones between the V- shaped notches and the cylindrical pins, since they are in point or linear contact. This combination leads to a poor degree of accuracy in locating the tool.

PROBLEM STRUCTURE

The present invention has for its object to design the device intimated by way of introduction such that the drawbacks inherent in prior art techniques are obviated. Thus, the present invention has for its object to realize such a device as permits rapid, simple and accurate location of the tool on the tool table. Finally, the present invention also has for its object to realize a device which also permits simple dismounting of the tool, irrespective of whether this takes place in a direction opposite to the mounting direction or in that same direction.

SOLUTION

These and other objects forming the basis of the present invention will be attained if the device disclosed by way of introduction is characterized in that the guide heels are disposed on the upper face of the tool table or the underface of the tool, while recesses intended for accommodating the guide heels are disposed on the underface of the tool or the upper face of the tool table, respectively, that the guide heels are switchable between inner positions inside the surrounding surface and outer positions where they extend beyond this surface, and that operating devices for the guide heels

are provided for transferring the guide heels to the inner positions when the tool is placed on the tool table and is moved therealong, and for transferring the guide heels to the outer positions when the recesses are located in register with each respective guide heel during the displacement of the tool.

According to one preferred embodiment, the mutually cooperating guide means are in the form of a groove and a guide pin engaging therein and displaceable therealong, and the guide heels are disposed one on either side of the groove or its prolongation.

As a result of this design of the device according to the present invention, it is sufficient for mounting a tool that the tool is placed on the tool table and shifted therealong so that the guide pin comes into engagement in its guide groove. In such instance, it is immaterial whether the tool is fed somewhat obliquely in its direction of displacement, since the tool can be pivoted somewhat about the guide pin. On placing of the tool on the tool table, or on displacement of the tool therealong, the guide heels are switched to the inner positions in order subsequently to be transferred - automatically or as a result of a suitable command signal - to the outer positions where they each engage in their recess in the tool. In such instance, it is immaterial whether the tool is slightly pivoted about the guide pin, since, in such an event, first the one guide heel will come into engagement with its recess, whereafter advancement of the tool continues such that the tool undergoes a combined rotation and translation movement until engagement is also established with the other guide heel.

Further advantages will be attained according to the present invention if the device according to the invention is also given one or more of the characterizing features as set forth in appended Claims 3 to 9.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The present invention will now be described in greater detail hereinbelow, with ^* particular reference to the accompanying Drawings. In th e accompanying Drawings:

Fig. 1 is a perspective view of a tool and a tool table, the tool being shown raised from its final, located position;

Fig. 2 is a perspective view of a retainer device for a guide heel, the retainer device being placed in a jig shown partly in cross section;

Fig. 3 is a partial section through the retainer device and jig of Fig. 2;

Fig. 4 is a side elevation partly in cross section of the tool and the tool table, the tool beginning to be advanced across the table;

Fig. 5 is a view corresponding to that of Fig. 4 of the tool in the desired, determined position; and

Fig. 6 is a magnified cross section through the jig with the guide heel.

DESCRIPTION OF PERTINENT EMBODIMENTS

In its most generic form, the device according to the present invention includes two mutually cooperating guide means on the tool 1 and tool table 2, these guide means being designed to guide the tool transversely of its direction of displacement 3, 3' in to the intended, accurately located position and back in the opposite direction therefrom along the tool table, respectively. These guide means are designed in such a manner that they also permit a certain pivoting of the tool in relation to the tool table about that point or that zone where engagement between the guide means takes place.

In one practical version, the guide means may consist of a guide groove 6 made in the upper face 4 of the tool table, in which groove a pin 7 may be accommodated and is movable along the groove.

The present invention further includes guide heels 8 or resilient bodies fulfilling the function of arrest or guide members which may be disposed both on the upper face 4 of the tool table 2 and on the underface 12 of the tool 1 proper. The guide heels are switchable between inner positions inside the surrounding surface and outer positions in which they extend beyond the surrounding surface. The guide heels may be operated by operating devices for the above-mentioned switching operation. For cooperation with the guide heels, there are corresponding recesses 13

which may consequently be placed both on the underface 12 of the tool 1 and on the upper face 4 of the tool table 2. Preferably, the guide heels and corresponding recesses are of relatively large geometric extent transversely of the longitudinal direction of the cooperating guide means 6 and 7 so that point loadings are thereby avoided when the guide heels enter into engagement.

The guide heels 8 and corresponding recesses 13 are also designed in such a manner that engagement may be established even if the tool were to be incorrectly rotated somewhat so that the longitudinal direction of the guide heels makes a slight angle with the longitudinal direction of the corresponding recesses 13.

The operating devices for the guide heels 8 may consist of springs 9 pretensioning the guide heels towards their outer position, and obliquely directed bevels 10, 10' on the forward edge areas in the direction of displacement 3, either of the underface of the tool or the upper face 4 of the table 2. However, such operating devices may also consist of hydraulic or pneumatic prime movers, mechanical drive apparatus etc.

A detailed description of one embodiment of the present invention will be given below. Those reference numerals which are accompanied by a primo symbol (') in this specification relate to the right-hand version of such fittings and details as are to be found one on both the left and the right- hand sides of the device.

In Fig. 1, reference numeral 1 refers to a tool and 2 to a tool table. For purposes of clarity, the tool is shown raised a slight distance above the tool table 2, but it should be emphasized that, on mounting and dismounting of the tool, the tool is displaced along the upper face 4 of the tool table 2. It should here also be observed that no direct contact between the tool table and the tool need take place, since the tool can be carried by various friction-reducing devices, such as rollers depressible in the tool table. The direction of displacement of the tool is indicated by reference numerals 3 and 3', in which 3' illustrates a dismounting direction. Jigs 5, 5' are disposed transversely, possibly at right angles, to this direction 3, 3', the jigs being recessed in the upper face 4 of the tool table. The jigs have longitudinal grooves, preferably of rectangular cross section. A different

number of jigs may also be employed. For example, a single long jig can be used, in which event this jig ideally extends from the one edge 23 of the tool table to its opposing edge 24. Retainer devices 18 are disposed in the grooves of the jigs, the retainer devices accommodating the above- mentioned guide heels 8. The guide heels 8 are in the form of resilient bodies upwardly biassed by means of springs 9, 9'. The number of springs in each retainer device 18 is not critical, but two springs would appear to be an appropriate alternative. The springs 9, 9' urge the resilient body upwards so that the upper face thereof extends beyond the surface 4 of the tool table. The resilient bodies with the springs 9, 9' may possibly also be placed directly in the groove of the jigs 5, without employing the above- mentioned retainer devices.

For lateral guiding of the tool 1 in relation to the tool table 2, i.e. transversely of the longitudinal direction 3, 3' for advancing the tool, there is provided a jig 6 with a longitudinal guide groove recessed in the surface 4 of the tool table 2. The jig 6, together with a guide pin 7 in the tool, caters for guiding of the tool transversely of the advancement direction 3, 3'. Thus, the guide pin runs in the longitudinal groove of the jig. Entry bevels for the guide pin are provided in the normal manner at the start of the groove. The guide pin is suitably movable in the vertical direction and impressible into the tool, and has a head which faces upwardly and is inserted in a hole in the tool. DBy its own weight, the guide pin depends as far as the head permits. In one case where the tool and tool table are employed sloping or in the vertical position, the guide pin 7 may also be provided with mechanical springing.

In the underface 12 of the tool, engagement members are provided for the guide heels, in the form of transverse grooves or recesses 13, 13'. The recesses are preferably of rectangular cross section, and the cross section is designed such that the guide heels 8, 8' or the resilient bodies can extend up into each respective recess. The recesses 13, 13' each project out to the side surfaces 25, 26 of the tool. The jigs 5, 5' of the tool table correspondingly project out to the side surfaces 23, 24 of the tool table. The number of recesses or grooves may be varied within broad limits, for example a single keyway which runs transversely across the underface 12 of the tool can be employed.

The underface 12 of the tool 1 is provided with entry devices or operating devices for the guide heels, in the form of bevels 10, 10' disposed between the underface 12 of the tool and its front face 11. The term "front face" is here taken to signify the front side 11 of the tool when this is advanced in the advancement direction 3. The purpose of these entry devices is to transfer or force down the guide heels 8 to their inner positions when the tool is shifted along the tool table 2. The guide heels 8, 8' can be shifted either alone or in their retainer devices 18 along the grooves of the jigs 5, 5 ^* . Normally, the guide heels 8, 8' are placed such that their outer short sides project somewhat outside the tool 1.

When the tool is to be advanced to the desired, determined position, it is first placed on the tool table in a position further back (seen in the advancement direction 3) than the desired end position. This is apparent from Fig. 4. When the tool is advanced from this position forwardly in the advancement direction 3, the bevels 10, 10' will force down the guide heels 8, 8' so that the tool can be shifted further. The underface 12 of the tool holds the guide heels 8, 8' depressed in their inner positions. In a slightly further advanced position, the guide pin 7 on the underface of the tool reaches the groove of the jig 6 and enters it. A guiding will thereby be achieved transversely of the advancement direction 3, i.e. in the lateral direction. In a yet further advanced position according to Fig. 5, the recesses 13, 13' reach the resilient bodies 8, 8' and these spring up into the recesses. Since the bodies lie partly outside the tool side, this may readily be verified visually.

The resilient bodies have at least one surface 14 which may be designated abutment surface or stop surface and which is transversely directed in relation to the upper face of the tool table 2, and preferably also transversely directed in relation to the advancement direction 3. Preferably, the surfaces 14 are at right angles both to the surface 4 of the table and to the advancement direction 3. On displacement of the tool in the advancement direction 3, one of the surfaces 14 will cooperate with a side 15 in the recess 13, this side being transversely directed, preferably at right angles, in relation to the underface 12 of the tool. Hereby, displacement of the tool is temporarily arrested. On continued positive displacement of the tool along the advancement direction 3, the tool will undergo a pivotal movement about an axis which is at right angles to the plane of the tool

table. This pivotal movement results in the second guide heel 8' also being transferred to the outer position where it is accommodated in the opposing recess 13'. In this position, the tool is correctly located whereupon it is locked in the table using conventional clamping means.

Since the jig 6 and guide pin 7 are placed centrally in the tool table and the tool, respectively in the lateral direction, tools of different widths can readily be employed together with the same tool table. Instead of two bevels 10, 10', a single continuous bevel can be employed along the entire front edge of the tool.

Fig. 2 shows in perspective a retainer device 18 which is shiftable in the grooves of the jigs 5, 5'. The resilient body 8, 8' (the guide heel) is preferably wedge-shaped with one sloping side 16 and the above- mentioned straight side or surface 14. Furthermore, the resilient body has an upper surface which may be planar and substantially parallel with the upper face 4 of the table 2, but which may also be arched. The resilient body has two parallel longitudinal sides 14, 27 with which it is guided in the grooves of the jigs 5, 5'. The retainer device 18 surrounds the resilient body on its short sides where it has catch-shaped projecting portions 19, 19', which serve as abutments for projecting edges 20, 20' on the short sides of the resilient body. Hereby, the elongation of the resilient body 8, 8' will be restricted. A number of springs 9, here two in number, are disposed between the bottom of the retainer device 18 and the resilient body 8. The resilient body is normally wedge-shaped with the sloping surface 16. When the retainer device 18 has been placed in the groove of the jig 5 and the resilient, wedge-shaped body is fully extended, the lower side of the oblique surface 16 will lie under the surface 4 of the tool table. This is apparent from Figs. 3 and 6. This implies that, on tool change (Cf Fig. 5), the tool may be drawn back in the advancement direction 3'. The resilient, wedge-shaped body 8 will then be urged down in that its oblique surface 16 is influenced by the forward, straight edge of the groove. In one case where the retainer device 18 is not employed but instead the resilient body with its springs 9, 9' lies alone in the groove of the jig, this effect can be achieved for example in that the resilient, wedge-shaped body bottoms out in the groove, or that projecting edges on the body bottom out on corresponding projecting edges on the side walls of the jig. The oblique surface 16 also permits the one guide heel first to enter into engagement

with its recess 13, and thereafter the tool to be pivoted somewhat in order to permit also the other guide heel to enter into engagement with its recess.

When tools of different widths are employed, the guide heels 8 and, where applicable, their retainer devices 18 are adjusted in the grooves of the jigs 5 in such a manner that the guide heels 8, 8' project beyond the side surfaces 25, 26 of the tool 1. It will hereby be easy to verify that the guide heels 8, 8' have actually extended completely into the recesses or grooves 13, 13' when the tool is advanced towards its intended position. On tool change, the conventional clamping means are first released and the tool is then drawn back in the described manner. An alternative tool change can be put into effect by drawing back the tool a few millimeters so that the guide heels 8, 8' are unloaded. They can thereafter be drawn out laterally along the grooves of the jigs 5 and be removed completely, since these grooves project all the way out to the side edges 23, 24 of the tool table. Alternatively, the guide heels can be held down under the action of their operating devices. The tool can subsequently be shifted forwards, i.e. in the advancement direction 3, and removed from the press. This may be desirable when the tool is moved aside to make room for a new tool. If tool change is only temporary, the original tool may be kept in an advanced position well forward in the advancement direction 3 on the tool table 2, while the new tool is located in the operative position. On return to the original tool, the new tool is removed following the procedure described above in the direction 3, whereafter the original tool is drawn back in the same direction, with the recesses 13 past the guide heels 8. Thereafter, the original tool is fed in the advancement direction 3 so that the guide heels enter into engagement, whereafter the tool is locked in the conventional manner.

It will be apparent from Figs. 4 and 5 that the guide pin 7 has a chamfered bottom end surface 21. In addition, the guide groove of the jig 6 has, at its inner end, a chamfered ramp surface 22. The purpose of these parts is that, on tool change forwardly in the advancement direction 3, when, for example, the old tool is shifted out of the press under the action of the new tool, the guide pin 7 is to be raised out of the guide groove either against the force of gravity or against possible spring loading by cooperation between these surfaces 21 , 22, in order subsequently, during the

remainder of the shifting movement, to slide with the end surface 21 on the upper face 4 of the table.

DESCRIPTION OF ALTERNATIVE EMBODIMENTS

According to the present invention, the resilient bodies 8, 8', i.e. the guide heels, can be designed with two longitudinal sides at right angles to the tool table. Such a box-shaped resilient body then cooperates with a groove 13, 13' which is so wide that the body can spring up between the walls of the groove, i.e. have suitable clearance. When the tool is to be changed, the resilient bodies must first be unloaded in order then to be drawn out laterally out of engagement with the tool. Furthermore, the tool table or the retainer device 18 may be provided with devices which urge down the resilient body so that its upper face lies below the surface of the tool table. These devices, for example levers, hydraulic or pneumatic cylinders etc., are activated for transferring the resilient body to the outer position when the tool is to be located. Otherwise, they can be disposed such that the resilient bodies are located in their inner positions at a level which makes the surface 4 of the tool table smooth and does not impede the movement of a tool thereon.

It is also possible to provide the jigs 5 with a drive motor and drive means, for example a feeder screw so that the retainer device 18 and resilient bodies 8, 8', respectively, may be moved along the jig with the aid of the drive motor. The inner short sides of the resilient bodies, i.e. those which are turned to face in towards the centre of the tool table, can be chamfered so that the resilient bodies 8, 8' (the guide heels) can be forced in under the tool with the aid of the drive motor. Thus, the bodies spring down when tool infeed takes place. Furthermore, each respective jig 5, 5' can be provided, proximal their outer end, with a downfeed edge which acts on the short side of the resilient body 8, 8' so that the body is urged downwards when it is driven with the aid of the drive motor towards the downfeed edge.

Bevels corresponding to the bevels 10, 10' may be provided on the opposing sides of the tool for depressing the resilient bodies when the tool is moved backwards in the direction 3'.

According to the present invention, a plurality of guide pins 7 may also be employed in order to provide an early guiding of the tool, which may be of benefit when no parallel advancement of the tool is provided. If such guiding is sufficiently accurate, the above-considered pivoting possibility of the tool is of less value.

In the foregoing, it has been assumed that both of the jigs 5 or those grooves which they define are in line with one another. However, this is not critical, but the grooves may instead make an angle with one another or be offset different distances in the advancement direction 3.

The above detailed description of one embodiment implies that the guide heels 8 are placed on the tool table. The reverse placement, with the guide heels on the underface of the tool is also possible. In such an alternative, the bevels 10, 10' must, however, be moved to the edge of the tool table 2 or, as intimated above, the guide heels 8 must be manoeuvrable between the inner and outer positions by means of some other operating device.

Irrespective of the placement of the guide heels 8, the jig 6 may be placed on the tool while, on the other hand, the pin 7 or a similar guide member is placed on the table.

Further modifications of the present invention are possible without departing from the spirit and scope of the appended Claims.