EP0165143A1 - Device for fitting and removing tools and accessories on a machine tool, especially a grinding machine - Google Patents

Abstract

Device for mounting and dismounting tools and accessories on a machine tool, in particular a grinding machine comprising a profiling head. The hub hub (22) and the cassette (14) have at one of their ends a housing (25, 54) having a groove (35) in which is likely to be engaged a gripper (36) an operating means (37) also comprising a thrust member (40) capable of selectively controlling locking members (27) of the grinding wheel hub (22) on the spindle and locking members of the wheel holder cassette on a mobile support member. The invention is used for mounting tools on a grinding machine.

Description

The present invention relates to a device for mounting and dismounting tools and accessories on a machine tool, in particular a grinding machine.

On machine tools, in particular mass grinders, changes of grinding wheels, wheel-holder cassettes and accessories make it necessary to automate the blocking, unblocking and handling operations of these members.

Indeed, the process of cutting in the mass by means of profile wheels makes it necessary to change these wheels frequently according to the profiles to be obtained.

Furthermore, this machining process requires frequent cutting of these grinding wheels. This profile is produced either by diamond coating or by a wheel with the appropriate profile.

The tendency to frequent profile changes has made it necessary to rapidly dismount these knurling devices.

These knobs are therefore mounted in preset cassettes which must then be positioned and locked on a support member for the knurling cassette holder.

The object of the present invention is to provide a device allowing the rapid automatic mounting and dismounting of the grinding wheel and the wheel-holder cassette.

According to the present invention the grinding wheel hub and the cassette have at one of their ends a housing having a groove in which is likely to be engaged a gripper for gripping an operating means also comprising a thrust member capable of selectively controlling locking members of the grinding wheel hub on the spindle and locking members of the wheel-holding cassette on a movable support member.

The device according to the invention comprises a locking mechanism built into the hub which prevents weakening of the spindle carrying the grinding wheel.

The device according to the invention can be actuated according to the installation by a simple manual grip, an automatic or semi-automatic tool such as a robot or a tool handling device.

Such an arrangement ensures handling without risk of falling of the element on the one hand by a positive locking of the gripping device, and on the other hand, by a logical control of the different phases of assembly and disassembly.

According to another characteristic of the invention, the jack has two chambers internally, one of which receives a first piston which is subjected on its two faces to the action of a compressed fluid, the other chamber receiving a second piston, the one of the ends extends outside the cylinder and which has an internal blind hole in which the rod of the first piston moves, the space between the bottom of the other chamber and the second piston as well as the space included in the blind hole being filled with hydraulic fluid.

This arrangement makes it possible to equip these machines with a dynamic balancing device for the grinding wheel which can be used on all the tools and which is automatically coupled to these when they are changed.

This means according to the invention makes it possible to couple the balancing device to the grinding wheel hub so as to ensure its rotational drive as well as its centering in a rigid manner to allow it to transmit the loads countering the vibrations.

Furthermore, in the device according to the invention, the balancing apparatus remains integral with a fixed element of the machine to allow disassembly of the tool without disassembly of said apparatus, this connection having to be isolated in terms of vibration so as not to harm to the operation of the whole.

• - la figure 1 est une vue en élévation latérale d'une rectifieuse perfectionnée suivant l'invention ;
• - la figure 2 est une vue en élévation de face et en coupe de la tête d'usinage ;
• - la figure 3 est une vue en élévation latérale et en coupe de la tête d'usinage ;
• - la figure 4 est une vue en coupe longitudinale du dispositif de montage et de démontage du moyeu porte-meule, la demi-vue supérieure représentant la meule montée et la demi- vue inférieure en cours de montage ou de démontage ;
• - la figure 5 est une vue en coupe longitudinale suivant la ligne V-V de la figure 3 du moyen de montage et de démontage du porte-cassette
• - la figure 6 est une vue en coupe axiale du moyen d'équilibrage de la meule ;
• - A la figure 1 on a représenté une rectifieuse qui comprend un bâti 1 sur lequel est monté coulissant horizontalement un montant 2 portant une poupée porte- meule 3 se déplaçant verticalement et sur laquelle est fixée à l'une de ses extrémités, un appareil à profiler 4 représenté plus en détail aux figures 2 et 3. L'appreil à profiler 4 se déplace à l'intérieur d'une enceinte fermée 5 disposée au-dessus d'une table d'usinage 6 sur laquelle est fixée la pièce à usiner.

Other features and benefits of the invention will be better understood on reading the description which follows of several embodiments and with reference to the appended drawings, in which:

• - Figure 1 is a side elevational view of an improved grinder according to the invention;
• - Figure 2 is a front elevational view in section of the machining head;
• - Figure 3 is a side elevational view in section of the machining head;
• - Figure 4 is a longitudinal sectional view of the mounting and dismounting device of the grinding wheel hub, the upper half-view representing the mounted grinding wheel and the lower half-view during mounting or dismounting;
• - Figure 5 is a longitudinal sectional view along line VV of Figure 3 of the mounting means and disassembly of the cassette holder
• - Figure 6 is an axial sectional view of the wheel balancing means;
• - In Figure 1 there is shown a grinding machine which comprises a frame 1 on which is mounted sliding horizontally an amount 2 carrying a grinding wheel doll 3 moving vertically and on which is fixed at one of its ends, a device to profiler 4 shown in more detail in FIGS. 2 and 3. The profiling device 4 moves inside a closed enclosure 5 disposed above a machining table 6 on which the workpiece is fixed .

The profiling device 4 (Fig. 2 and 3) comprises a frame 7 on which is mounted at its lower part a rotary spindle having a cone 9 on which is fixed a grinding wheel for machining the parts.

Above the grinding wheel and parallel to its axis is rotatably mounted a wheel 11 intended for cutting the profile of the wheel 10, said wheel 11 being fixed to a rotary shaft by means of bearings 13,13a, on a cassette 14, said shaft 12 being connected to a motor member for driving in rotation.

The cassette 14 is removably mounted on a support arm 15 fixed to the lower end of a tubular beam 16 which has at its upper part a nut 17 engaged on a ball screw 18 on which is fixed a pulley 19 connected by a toothed belt 20 to a pulley 21 wedged at the end of the shaft of a motor member 22.

This arrangement allows the rotation screw of the ball screw 18 and the nut 17 to ensure a displacement - vertical. of the cassette 14 and of the thumb wheel 11 to bring the latter closer or further away from the grinding wheel 10 for its cutting.

As shown in FIG. 4, the grinding wheel 10 is mounted on the cone 9 of the spindle by means of a hub 22 on which the grinding wheel 10 is tightened by a cheek 23 and screws-24.

The grinding wheel hub 22 has a housing 25 in which is fixed in the bottom a sleeve 26 internally receiving the jaws of a clamp 27 which is engaged on a head 28 formed at the end of a sliding rod 29 fixed on a disc 30 slidably mounted in the housing 25 and subjected to the action of a stack of elastic rings 31 bearing at its other end against a shoulder of the sleeve 26. At its end directed towards the opening of the housing 25 the rod 29 is provided with an adjustable stop 32 intended to bear against a thrust member.

The jaws of the clamp 27 are engaged under the action of the elastic washers 31 and of the rod 29 in a groove 33 of a nose 34 formed at the end of the cone 9 for driving.

The jaws of the clamp 27 are guided by a locking ramp 26a, shaped inside the sleeve 26.

Near the opening of the accommodation 25, a groove 35 is provided in which the jaws of a gripper 36 mounted on an operating means are engaged.

The maneuvering means consists of a movable arm 37 mounted in particular on a robot or a handling device, said arm 37 containing a jack whose cylinder 38 fixed therein has at one of its ends a screwed sleeve 39 delimiting between the latter and the end of a piston 40 which extends outside the cylinder an annular space 41 in which the jaws of the gripper 36 are mounted which are guided by a ramp 42 provided on the end of the piston 40. Said piston 40 also playing the role of the thrust member which acts by its end face 43 against the stop 32 integral with the rod 29 controlling the clamp 27.

The cylinder 38 has two chambers 44 and 45 inside which are separated by a watertight partition 46.

One of the chambers 44 receives a first piston 47 subjected on its two faces to the action of a compressed fluid, in particular compressed air.

The first piston 47 is provided with a rod 48 which passes through the partition 46 and which is capable of extending into a blind hole 49 of the second piston 40, which slides in the second chamber 45. The space between the second piston 40 and the partition 46 as well as the blind hole 49 contain a hydraulic fluid.

The device for mounting and dismounting the wheel holder operates as follows.

The grinding wheel hub 22 being fixed on the nose 34 of the cone 9 of the spindle as shown in the upper half-view of FIG. 4, the jaws of the clamp 27 are engaged in the groove 33 of the nose 34 of the cone 9 under the action of the elastic washers 31 which act through the head 28 of the rod 29 on said jaws of the clamp.

To disassemble the grinding wheel, approach the arm 37 of the operating means, as shown in the upper half-view of FIG. 4.1e first piston 47 being on the right the rod 48 is not engaged in the blind hole 49 of the second piston 40 which is pushed back right in chamber 45 of the cylinder. The clamp 36 is in the open position in order to enter the housing 25 opposite the groove 35.

By actuating the first piston 47 to the left, the rod 48 enters the blind hole 49 of the second piston 40 which, under the action of the hydraulic fluid, moves to the left as shown in the lower part of FIG. 4.

This results in a displacement of the jaws of the clamp 36 which engage in the groove 35 of the hub 22, simultaneously the end 43 of the piston 40 pushes the rod 29 to the right causing the clamp 27 to open and its release from the throat 33 from the nose 34 from the cone 9.

It then suffices to move the arm 37 to the right to disassemble the grinding wheel 10 from its cone 9, the hub 22 being fixed to the arm by the gripper 36.

To assemble another wheel, proceed in the same way but in reverse.

At the end of the second piston 40 there is provided a conduit 50 which opens at this end and which ensures both the detection of the presence of the member to be dismantled which closes the conduit 50 and the systematic cleaning of the conical surfaces.

This detection allows the normal course of the cycle, via the control automaton. Without it, the device returns to its starting point for a new part grip test.

The detection carried out, the piston 40 is therefore in contact with the disc 30 subjected to the elastic members and compresses the latter until the complete release of the locking system.

The hub 22 thus removed can be handled without risk of falling,

The removal of the grinding wheel carrier hub 22 on its receiving element is carried out, after installation, by eliminating the compression effect of the elastic washers 31, thus ensuring the locking of the hub.

The elastic rings 31 push the piston 40 to the intermediate position. Simultaneously, a cleaning blowing is carried out through the conduit 50 through all of the mechanisms. Locking of the rested hub is detected by closing the blowing duct 50.

If this signal is not recorded, the operating means cannot be separated from the grinding wheel hub 22.

Although a hydro-pneumatic control has been used, it is obvious that the clamps 27 and 36 could be operated differently, in particular by a simple manual grip (such as a hub puller) or a semi-automatic tool.

For the assembly and disassembly of the wheel-holder cassette, the same assembly and disassembly means are used, in particular the operating means described above (Fig. 4).

This arrangement which is shown in Figures 2, 3 and 5 comprises the cassette 14 which is slidably mounted by two of its edges 51 in two grooves 52 of the support arm 15 where it is held by locking members.

The cassette 14 is extended on one side by members 53, 53a which delimit a housing 54 similar to that of the grinding wheel hub 22 defined above, near the opening of this housing there is provided a groove or groove 55 intended to receive the jaws of the clamp 36. Between the support 15 and the cassette 14 are arranged combs 56 which guarantee the positioning of the case sette in the grooves of the support arm 15, said combs being supported by means of two rows of pins 57, 57a, against elastic washers 58, 58a.

The pins 57, 57a each have at their upper part an inclined groove 59 in which are engaged the edges of two rods 60, 60a, slidably mounted in the body of the cassette 14 perpendicular to the axes of the pins 57, 57a, said edges being delimited by oblong holes 61, 6la formed in said rods and in which are engaged the pins 57, 57a. The edges of said oblong holes 61, 6la having an inclined ramp 62, the displacement of the rods 60, 60a causes. the displacement of the pins 57, 57a by compressing the elastic washers 58, 58a thus canceling their action and allowing the release of the cassette from its support.

At one of their ends, the sliding rods 60, 60a are subjected to the action of stacks of elastic washers 63, 63a which push said rods against the ends of a lifting beam 64 guided in the housing and having in its central part a stop 65 against which is likely to come to bear the end 43 of the piston 40 of the operating means described above.

The cassette 14 being mounted in its support arm 15 as shown in Figures 2, 3 and 5 the pins 57, 57a under the action of the springs 58, 58a ensure the locking of the cassette in its support.

To disassemble the cassette, the end of the operating means shown in FIG. 4 is engaged in the housing 54 so that the jaws of the clamp 36 engage in the groove 55 of the entrance to the housing 54.

By actuating the clamp 36 the piston 40 comes simultaneously into contact at its end 43 with the stop 65 which by the spreader 64 push the rods 60, 60a to the right, against the action of the elas washers ticks 63, 63a, By the play of the ramps 62, of the rods 60, 60a, the pins 57, 57a are raised by compressing the elastic washers 58, 58a to release the cassette 14 which is mounted on the arm 37 of the member operation by the clamp 36 thus allowing its displacement and its replacement by another wheel-holder cassette 14.

To re-lock the new cassette in position, after engaging the edges 51 in the grooves 52, it is sufficient to release the pressure on the spreader 64, so that the washers 63, 63a push the rods 60, 60a, to the left and that the ramps 62 allow movement of the pins 57, 57a, and the locking action of the elastic washers 58, 58a on the cassette.

As shown in FIGS. 1, 3 and 6 on the door 66 of the wheel housing, a balancing device 67 is installed in the axis of the wheel 10, said device being fixed by bolts 68 with the interposition of elastic elements 69, on door 66, from which it is isolated in terms of vibrations.

The automatic opening of the door therefore releases the balancing device and the grinding wheel to be dismantled, thus in no way hampering this operation.

When a new tool is in place, the closing of the door 66 returns the balancing device 67 of the grinding wheel which carries a conical intermediate member 70 coming to engage in the conical inlet 71 of the hub 22 in order to center the device in the hub.

Any alignment faults are compensated for by the elastic members 69, the stress applied to them then guaranteeing the axial reaction RA generated on the cone under the effect of vibrations to contern Fr (radial load).

The positive drive in rotation of the balancing device is provided by pins. 72 screwed in holes provided in the hub 22 and engaged in holes 73 provided in the intermediate member 70,

These pins 72 are retractable to avoid having to index their position relative to that of the holes in the hub. The slightest slip at the start of the assembly then allows them to engage in these holes thus preventing any angular offset of the assembly in operation.

Of course, the invention is not limiting and those skilled in the art may make modifications to it without departing from the scope of the invention.

Claims (9)

1. Device for mounting and dismounting tools and accessories on a machine tool, in particular a grinding machine comprising a profiling head on which are mounted a rotary spindle carrying a grinding wheel hub and a cassette carrying a cutting wheel. of the grinding wheel, characterized in that the grinding wheel hub (22) and the cassette (14) have at one of their ends a housing (25, 54) having a groove (35, 55) in which is capable of '' be engaged a gripper (36) of an operating means (37) also comprising a thrust member (40) capable of selectively controlling locking members (27) of the grinding wheel hub (22) on the spindle and locking members (57, 57a, 58, 58a) of the wheel holder cassette (14) on a movable support member (15). 2. Device according to claim i, characterized in that the grinding wheel hub (22) has a housing (25) having, near its opening, a groove (35) in which the pliers (36) can be engaged operating means, said housing itself containing a clamp (27) whose jaws are capable of being engaged in a groove (33) provided on a nose of the rotary spindle (9) under the action of elastic members ( 31) and to be released from the groove under the action of a pusher (29, 30) compressing said elastic members (31) causing the opening of said jaws of the clamp (27 said pusher (29, 30) being actuated by the thrust member (40) of the operating means. 3. Device according to claim 1, characterized in that the wheel-holder cassette (14) is slidably mounted by two of its edges (51) in two grooves (52) of a support member (15) where it is held by locking members, said cassette (14) having a housing (54) provided near its opening with a groove (55) in which the gripping pliers (36) of the actuating means can be engaged glass (37), said housing containing a lifter (64) subjected in its central part to the action of the thrust member (40) of the operating means and bearing at its ends against two rods (60, 60a) of control of the locking members. 4. Device according to claim 3, characterized in that the locking members of the wheel-holder cassette (14) on its support (15) consist of pins (57, 57a) slidably mounted perpendicular to the control rods (60 , 60a) in which they are engaged in oblong holes (61, 61a) and having an inclined groove (59) in which is engaged a ramp (62) of the control rods which act against elastic members (58 , 58a) maintaining said pins (57, 57a) in the clamping position against the support member (15). 5. Device according to claim 4, characterized in that between the pins (57, 57a) and the support are arranged combs (56) provided with teeth and ensuring the positioning of the cassette (14). 6. Device according to claim 1, characterized in that the operating means consists of a movable arm (37) in which is mounted a jack whose cylinder (38) has at one of its ends a sleeve (39 ) delimiting between the latter and the end of a piston (40) which extends outside the cylinder (38) an annular space in which the jaws of the gripper (36) are mounted which are actuated by a ramp (42) formed on the piston (40), the end of which constitutes the thrust member acting on the locking members of the grinding wheel hub (22) and of the wheel-holder casing (14). 7. Device according to claim 6, characterized in that the cylinder internally comprises two chambers (44, 45), one of which (44) receives a first piston (47) which is subjected on its two faces to the action of a compressed fluid, the other chamber (45) receiving a second piston (40) one end of which extends outside the cylinder (38) and which has an internal blind hole (49) in which the rod (48) of the first piston (47) moves, the space between the bottom of the other chamber (45) and the second piston (40) as well as the space included in the blind hole being filled with a hydraulic fluid. 8. Device according to claims 6 or 7, characterized in that at the end of the piston (40) opens a compressed air duct (50) acting as a tool presence detector (10, 11) and cleaning of tool locking mechanisms. 9. Device according to claim 1, characterized in that on the door (66) of the wheel housing (10) and in the axis of the grinding wheel spindle is fixed by elastic members (69) a balancing device (67) which has a conical centering part (70) adapting to the inlet of the grinding wheel means (22) which is provided with pins (72) engaging in holes in the balancing device for its positive rotation drive.

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