FR2562179A1 - Device for automatically fastening a tool on a support - Google Patents

Abstract

Device for fastening a machining tool on a positioning grid comprising at least one hollow barrel. According to the invention, the barrel 2 has, in its front portion, a groove 2b in which there are included, in a locking position, balls or the like 1, which can be disengaged from the groove 2b by translation of a ring 4, 14 whose movement is controlled by the introduction of a pressurised fluid via a duct 6, 12. Applications: fastening of a machining tool by a robot on a positioning grid.

Description

DEVICE FOR AUTOMATICALLY FIXING TOOLS ONTO A
SUPPORT.

The present invention relates to a fixing device intended in particular, but not exclusively, for fixing on a grid or any other support in general of a tool brought by a robot, or by any mechanized or manual positioning means in view machining a part that cannot be mounted on a machine tool
The problem of machining bulky and heavy parts is very frequent, for example in aeronautics or in the automobile industry. It is not possible in this case to bring the part under the tool but, it is the tool which must be positioned relative to the part.

It can be, for example the production of holes or a local surfacing.

To carry out such machining, it is known to have a grid in front of the part on which the tooling is fixed. This fixing is usually carried out by a fitting operating by quarter-turn blocking or according to a baronet mounting, or again by screwing on a pin of the grid.

It is known, moreover, to carry out such operations, in places which are often inaccessible, to use robots whose interface is constituted by a manipulator arm articulated with several degrees of freedom and which constitute means for guiding or positioning and / or tool drive.

Unfortunately, known fastening devices, using even partial rotation, can be used for mounting a tool, using a robot, on a positioning grid, but at the expense of a degree of freedom of positioning. Indeed, the robot arm, to be effective during the actual work must retain all its possibilities of action, and in particular the possibility of rotation of the end of its arm.

It is therefore necessary, for this application to have a fixing device which is simple, to be able to be implemented by a robot at a relatively high speed, which does not call for rotation, even partial, and which is reliable, the locking of the device being automatic and its unlocking being controlled by the robot itself according to its work program.

The present invention relates to a fixing device meeting the above requirements.

According to the present invention, the device for fixing a tool or the like on a positioning grid comprising a barrel projecting from the outside of the grid is characterized in that said barrel comprises in its front part a groove in which come insert locking pieces held in said groove by a second outer ring movable in translation, the locking pieces being able to escape from the groove by a movement of the outer ring.

Thus, the locking and unlocking of the binding result from the radial movements of independent locking pieces and for example of balls, themselves controlled by a single translational movement.

Other characteristics and advantages of the invention will emerge from the description which follows of a particular embodiment of the invention, given solely by way of nonlimiting example, with reference to the single figure which is a half vertical section of a fixing device according to the invention.

We distinguish in the figure a grid G or more generally any support pierced with orifices in the # squels are subject to hollow barrels 2 on which can be fixed a tool, such as a drill for example, the barrels 2, of which only one appears in Fig., serving as a support element and support for the tooling or the like.

Although the grid G is shown in a vertical position, it goes without saying that this grid can be in any position. The barrel 2 carries in its front part, on the side opposite to the workpiece, symbolized in FIG. by a vertical line, a groove 2b. This groove is intended to receive a set of balls 1, only one of which appears in FIG. , regularly distributed inside the throat.

Surrounding the balls 1 is provided an outer ring 4 secured to a skirt 14, the assembly being able to slide on a bush 3 mounted on the nose of the machining machine. The centering of the tool or more generally of the object to be fixed is ensured by the penetration of a barrel 8 inside the spindle 2. Lugs 9 ensure the locking of the socket 3 and of the nose 8 in rotation .

The rear part 7 of the sleeve 3 determines, with the internal surface of the ring 14, two cylindrical chambers. In the first chamber is mounted a return spring 5 which projects the ring 4.14 to the left of FIG. The second chamber, isolated from the first by the heel of the part 7 is in communication with a conduit 6, itself connected to a nozzle 12 connected, via the robot (not shown) to a source of pressurized fluid , such as air for example. The duct 6 is closed, to the right of the
Fig. by a plug. The nose 8 is continuously pushed forward by a return spring 10 bearing, on the one hand, against a stop surface 11 provided in the rear part of the nose 8 and, on the other hand, against a stop 13 integral with the machining machine. The front face of the nose 8 thus constantly bears against the surface to be machined.

Of course, seals, not referenced are arranged so as to maintain the necessary seal.

Fig. shows the device in the locked position.

According to a characteristic of the invention, this position is that which is obtained in the absence of supply of compressed fluid. It is thus certain that, if a fluid supply failure occurs, the machining machine remains fixed on its positioning grid.

The machining machine being in the position shown in Fig., When the work is finished, the robot sends via the nozzle 12 a compressed fluid. This fluid enters the second chamber and the movable wall formed by the bottom of the ring 4,14 moves to the right of FIG. and has above the balls 1 a ramp 15 freeing, at the end of the translation, sufficient space for the balls 1 to be able to come out of the groove 2b, without thereby falling, so that at this moment the device is unlocked . The machine can then be gripped by the robot arm, or even manually, and taken to another spindle to start another machining.

Of course, the recoil movement of the ring 4.14 can be caused not only by an injection of pressurized fluid but also by an electromagnet, or even, in the event of a breakdown, by hand since it suffices to move the ring 4 , 14 against the return spring 5.

 Thus, the locking of the machine is ensured automatically by a single translational movement which allows the robot to leave an axis of freedom. The unlocking order is given directly by the robot, or by any other remote control device, through its arm.

In addition, when the machine normally has a handle, the movement of the machine body and the handle around its axis is no longer necessary, which allows access in confined places.

It goes without saying that many variants can be introduced, in particular by substitution of equivalent technical means, without departing from the scope of the invention as defined by the appended claims.

Claims (2)

10 Attachment device for a machining machine or the like  on a positioning grid comprising at least one  barrel protruding from the outside of the grid,  characterized in that the barrel (2) has in its part  before a groove (2b) into which are inserted  locking pieces (1) held in the groove (2b)  by an outer ring (4,14) slidably mounted on a  sleeve (3), the parts (1) being released from the groove  (2b) by a movement of the ring (4.14).  20 Device according to claim 1, characterized in that  the movements of the ring (4.14) are determined in a  direction by a return spring (5) and, in the other direction,  by the introduction of a pressurized fluid by the  duct (6,12), the corresponding locking position  blocking of the locking parts (1) in the groove  (2b) under the action of the spring (5).  36 Device according to one of claims 1 or 2,  characterized in that a nose (8) is introduced at  inside the barrel (2), and applied against the part to  machining by a return spring (10) bearing on the one hand  on a fixed stop (13) and, on the other hand, on a surface  stop fixed to the nose (8).