GB2031777A

GB2031777A - Tool changing

Info

Publication number: GB2031777A
Application number: GB7922095A
Authority: GB
Original assignee: Maschinenfabrik Heid AG; Machinefabrik Heid AG
Current assignee: Maschinenfabrik Heid AG; Machinefabrik Heid AG
Priority date: 1978-06-23
Filing date: 1979-06-25
Publication date: 1980-04-30
Also published as: AT356475B; ATA460478A; DE2925341A1; GB2031777B

Abstract

A tool-changing device, particularly for lathes, is associated with a drum or chain magazine 1 with receiving pockets 4 for the insertion of tool holders 3. The magazine is set up independent of the lathe, and a loading arm 5 which can be pivoted around an axis parallel to the axis of rotation of the machine is provided for transporting the tool holders between the magazine and a tool clamping block 8 on a slide 6. The arm 5 lies alongside the magazine or the clamping block. Lateral pushes transfer the holders to and from the arm. Preferably a slide is arranged on the loading arm which has mountings 7 for two tool holders and which can be displaced along the loading arm into at least two positions, to enable interchange of holders at the clamping block. <IMAGE>

Description

SPECIFICATION Tool-changing device The invention relates to a tool-changing device, particularly for lathes, wih a drum or chain magazine with receiving pockets for the insertion of tool holders, and a transfer device.

Tool-changing devices of this kind are known, but the systems available all have greater or lesser disadvantages. For instance, chain magazines are known wherein the working area of the tool, which is determined by the arrangement of the steel holders in the chain, is restricted, so that certain machining operations cannot be carried out. In other changing devices the tool operating area, and particularly the length of drill rods, is restricted by the transfer guideways.

Changing devices are also known wherein the tools are brought from the magazine to the machine by one or two gripper arms.

These grippers are equipped with complicated mechanisms which are expensive and unreliable, and generally restrict both tools and working space.

There exists the problem of devising a system with which neither the tools nor the working space are restricted, which has a wide storage capacity and, in addition, which allows short change-over times. It should be possible to use the device equally for facing machines or centre lathes; it should preferably be provided with 20, 30 or more tool holders for storing considerable numbers of tools, and it should be especially suitable for complicated tools with wide operating areas.

This problem is solved according to the invention by a tool-changing device of the kind described in the introduction which is primarily characterised in that the magazine is set up independently of the lathe, and a loading arm which can be swivelled around an axis parallel to the axis of rotation of the machine is provided for conveying the tool holders between the magazine and the clamping block. According to a further characteristic of the invention a slide is provided on the loading arm, has mountings for at least one tool holder, and can be displaced along the loading arm into at least two positions. According to the invention provision is also made for the loading arm to form an angle with the horizontal when in its terminal position at the magazine, and for the tool holder pockets in the magazine to be inclined parallel with it.Finally, there is the further advantage that on the loading arm, on the tool holder pockets and on the clamping block guideways are provided corresponding with axis-parallel receiving guideways on the tool holders (for example, as in VDI 3425, Sheet 3 and 4).

The tool-changing device according to the invention thus has a preferably stationary drum or chain magazine which is set up separately from the machine, and a transfer device in the form of a pivotable loading arm, which is mounted on the magazine or on the machine, and may equally well be set up independently. The loading arm can be pivoted around an axis parallel to the axis of rotation of the machine and is advantageously equipped with a slide for receiving the tool holders; this slide can be displaced along the loading arm into several positions.As will be appreciated, these arrangements make possible a simple transfer movement, and make it possible to bring the magazine up very close to the lathe, since for loading and unloading the slide can be extended towards the vicinity of the magazine and subsequently retracted again in a straight line, the pivoting movement not being carried out until after this.

The above advantage, and the advantage that tools with a wide operating area can be accommodated in the magazine without restriction, is achieved due to the fact that the loading arm is inclined at an angle to the horizontal in the loading or unloading position, and the tool pockets in the chain magazine are correspondingly inclined. This reduces the pivoting path of the loading arm considerably.

The technically most simple and most advantageous solution for mounting the tool holders in the magazine, on the loading arm and in the clamping block is achieved by equipping the loading arm, magazine pockets and clamping block with receiving guideways which correspond to the receiving guideways in the tool holders, which are standardised specifically according to VDI 3425, Sheet 3 and 4. In this way, no additional holding elements such as clamping strips are necessary on the individual component parts, for example, on the tool holders.

The subject of the invention is described in more detail in the following on the basis of a construction example, with reference to the Drawing in which Fig. 1 is a schematic side view of a lathe with a tool-changing device according to the invention, Fig. 2 shows schematically the position of the important parts of the lathe during transfer of the tool holder, viewed from above, and Fig. 3 shows the positions of the tool holder, the slide and the magazine pocket during the various phases of a tool-change.

A lathe can be seen in Fig. 1, with a bed 2, a face-plate 9, a carriage 6, clamping equipment 8 (clamping block) arranged on the carriage 6, and a clamped-in tool holder 3A with a tool. Furthermore, on the lathe a loading arm 5 is arranged which can pivot around an axis parallel to the axis of rotation and bears a holding slide 7 which can be displaced along the loading arm 5 into three positions and bears two dovetail guideways for receiving the tool holders. At a distance behind the lathe a chain magazine 1 is set up locationally fixed, having tool holder pockets 4 which, in the transfer position-where thus either a tool holder is being transferred from the pocket 4 to the receiving slide 7 on the loading arm 5 or vice versa-like the loading arm 5 and parallel thereto, form an angle with the horizontal.It will be appreciated that in this way on one hand the pivot path of the loading arm 5 is limited so that the magazine 1 and the lathe can be brought closer together, and on the other hand tool holders with a great extent, such as drill rods, can also be accommodated in the tool holder pockets 4 without the tool holders in adjacent pockets touching each other. Consequently, this means that, compared with magazines which have a horizontal movement of the tool holder pockets, a greater magazine capacity can also be obtained. In one of the tool holder pockets 4, which is aligned with the receiving slide 7 when the loading arm 5 is in the transfer position, a tool holder 3B is inserted, the receiving slide 7 and the tool holder pockets 4 having axis-parallel dovetail guideways, corresponding complementary profiling being provided on the tool holders 3.

Such profiling is standardised, for instance, in VDI 3425, Sheet 3 and 4.

In Fig. 2 it will be seen that, for the tool change-over, the machine carriage 6 with the loading arm 5 is moved so that the tool holder clamped in the clamping block 8 is lined up with the tool holders in the magazine. The loading arm 5 is then located between the clamping block 8 and the main spindle 9 of the machine (face-plate) and in the two terminal positions of the loading arm 5 the guideways in the receiving slide 7 are directly adjacent to the tool holders inserted in the clamping block 8 or in the magazine pocket 4 respectively. Now the loading arm 5 is brought into one of the terminal positions as shown in Fig. 1, and the receiving slide 7 is moved out until the inner guideway nearest to its pivot axis is lined up with the guideway in the magaxine pocket 4 in which the tool holder 3B is held (Phase 1 in Fig. 3).

Then the tool holder 38 is pushed by the loading device 10 into the receiving slide 7 (Phase 2 in Fig. 3).

Now the receiving slide 7 is retracted sufficiently far so that, after the subsequent pivoting of the loading arm 5 into its other terminal position, the empty, outer guideway on the receiving slide 7 is lined up with the tool holder 3A clamped in the clamping block 8. When the receiving slide 7 is retracted into this position the receiving slide 7 leaves the vicinity of the magazine 1 (Phase 3 in Fig. 3).

Now the loading arm 5 is pivoted into its other terminal position in the vicinity of the clamping block 8, the tool holder 3A is released from the clamping block 8 and is pressed by the loading divice 11 into the free outer guideway in the receiving slide. Now the tool holder 3A which is to be replaced and also the new tool bolder 3B are noth held in the receiving slide 7 (Phase 4 in Fig. 3).

The receiving slide 7 is extended so that the new tool holder 3B lies opposite the guideway in the clamping block 8; the new tool holder 3B is drawn into this guideway by the loading device 11 and is clamped fast in the clamping block 8 (Phase 5 in Fig. 3).

Now the loading arm 5 is pivoted back into its terminal position at the magazine in which the replaced tool holder 3A lies opposite the guideway in the tool holder pocket 4 of the magazine 1; the tool holder 3A is then drawn into the tool holder pocket 4 by the loading device 10 (Phase 6 in Fig. 3).

The loading arm 5 is then pivoted into an intermediate position (waiting position), and the magazine chain brings the tool holder required for the next change into the handover position on the magazine.

Alternatively, the loading arm 5 may also remain in its terminal position at the magazine 1 until the next change. In this case, the receiving slide 7 is retracted so that it does not obstruct the movement of the magazine. It is also possible to retract or extend the receiving slide 7 on the loading arm 5 during the pivoting movement of the loading arm 5.

With the apparatus according to the invention it is possible to shorten the tool changing time considerably, since only phases 4, 5 and 6 have to be taken into account, whilst phases 1, 2, 3 and 7 are carried out while the machine is operating.

Claims

1. A tool-changing device particularly for lathes, with a drum or chain magazine with receiving pockets for the insertion of tool holders, and a transfer device, characterised in that the magazine is set up independent of the lathe, and a loading arm which can be pivoted around an axis parallel to the axis of rotation of the machine is provided for transporting the tool holders between the magazine and the clamping block.

2. A tool-changing device according to Claim 1, charzcterised in that on the loading arm a slide is arranged which has mountings for at least one tool holder and can be displaced along the loading arm into at least two positions.

3. A tool-changing device according to one of Claims 1 and 2, characterised in that in its terminal position at the magazine the loading arm forms an angle with the horizontal, and the tool holder pockets in the magazine are inclined parallel thereto.

4. A tool-changing device according to one of Claims 1 to 3, characterised in that on the loading arm, on the tool holder pockets and on the clamping block guideways are provided corresponding the axis-parallel re ceiving guideways on the tool holders (for example, according to VDI 3425, Sheet 3 and 4).

5. A tool-changing device constructed, arranged and adapted for use substantially as hereinbefore described with reference to the accompanying drawing.