FR2547230A1 - Automatic tool-changing device, especially for machine tools - Google Patents

Abstract

The device essentially comprises a rotary magazine for positioning tools, and a handling unit equipped with at least one tool-holding arm with a gripper, the said handler being securely fastened to a member for rotationally controlling a drum which peripherally has at least two grooves of suitable profile and in combination with the mechanical assembly, allowing the linear displacement in both directions (advance and retraction) of the gripper P of the tool-holding arm C, the other cam 10b via another suitable profile allowing, in combination with the two separate mechanical assemblies, on the one hand, the tool-holding arm C to be raised and lowered and, on the other hand, the said arm C to be rotated in a horizontal plane, these two movements being separate. The member for rotationally controlling the drum and the member for controlling the magazine being securely fastened to an automatic position-control device. The device is used in particular to be fitted to all machine tools with a horizontal or vertical spindle.

Description

 The subject of the invention is an automatic tool changer device, in particular for machine tools.

 The object of the invention relates to the technical sectors of machine tools and handling means.

 Currently, numerically controlled machines, by simplifying their programming and their increasing performance, are gradually entering light mechanical or micro-mechanical workshops. The market for numerically controlled machines, generally of small capacity, is increasing as a result of the evolution of electronics techniques which tends to an increasingly advanced miniaturization.

 On the other hand, cutting tools, whose increased performance reduces production times, the speed of tool change between each operation becomes an important performance criterion.

 To meet these requirements, it appeared necessary to create a new type of tool changer comprising, in a known manner, a rotary magazine receiving the tools and a manipulator block equipped with at least one gripping arm.

 According to one characteristic, the manipulator is shaped and arranged to allow a complete cycle of tool changes to be carried out - extraction of the tool from the spindle of the machine tool then placement of said tool in the magazine - extraction of the tool from the magazine and placement in the spindle.

 The movements necessary for these operations are controlled by an electric motor with two directions of operation which actuates a system of suitably profiled cams and of variable amplitude, the said cams cooperating with appropriate members for transmitting the gripping arms the preset movements, said motor being subject to a position control in combination with the magazine.

This results in the next cycle
For extracting the tool from the magazine, with a view to placing it in the spindle - The gripping arm being positioned in the direction of the magazine, c brings the chosen tool into axial alignment with said arm.

- The arm is deployed linearly to grasp the tool.

- We lower the arm equipped with the tool.

- We fold the arm.

- We act in rotation on the arm to bring it opposite the spindle of the machine tool.

- The arm is deployed linearly.

- The arm is raised to the latching position of the tool in the spindle of the machine.

- Remove the arm and bring it back to the initial position.

For the reverse operation, that is to say the extraction of the tool from the spindle of the machine tool for storage in the store, the cycle is very much the same, but the motor is controlled in reverse to the previous one.

 These characteristics and others will become apparent from the following description #.

 To set the subject of the invention, without however limiting it, in the accompanying drawings.

 Figure 1 is a perspective view of the changer device according to 1 invention.

 Figures 2 to 9 are front views showing the different phases of the device operating cycle in the case of removing the tool from the magazine and placing it in the spindle of the machine.

 Figure 10 is a longitudinal sectional view of the store.

 FIG. 11 is, on a larger scale, a view in longitudinal section considered along line 11-11 of FIG. 1.

 FIG. 12 is a sectional view taken along line 12-12 of FIG. 11.

 FIG. 13 is a sectional view taken along line 13-13 of FIG. 11.

 In order to make the object of the invention more concrete, it is now described in a nonlimiting manner with reference to the exemplary embodiments of the figures of the drawings.

 We see in Figure 1 that the device essentially comprises a rotary magazine (M) for positioning the different tools (o) and a manipulator block (B) equipped with at least one tool-carrying arm (C) with gripper (P ).

The whole store (M) with. his manipulator (B) is my
s t on a common support base easily movable to be adapted to any machine tool, leaving free the entire working field of the machine. It should be noted that the device according to the invention can be adapted to all machines with horizontal or vertical spindle, whether they are traditional cycled or with digital control.

 As shown in Figure 10, the magazine (M) consists of a circular support plate (1) having peripherally different pots (2) shaped to receive the tools (O). This plate (1) is integral with a central shaft (3) disposed vertically and on which is mounted free in rotation a console (4) supporting a DC gear motor (MR).

This gear motor has at the end of its axis of rotation
a pinion (5) meshing with a crown (6) which appears at the base of the plate (1).

 The rotation of the magazine is controlled by a means of control and reading of the position subject to the entire position control.

 The manipulator unit (B) has a two-phase motor (8) with two directions of movement which drives in rotation, by belt (9) or other coupling means, a drum (10) mounted rotating in bearings A-P1) relative to the flanges of the protective casing (CF the axis. of said drum being disposed horizontally. The drum (10) has peripherally at least two grooves profiled in cam (lOa and lOb) capable of being angularly adjusted I'opop raF port à l In fact, provision is made to execute the drum (10) and two separate parts # (vioc and lOd).

 According to the invention, the first cam (lOa) by a suitably suitable profile and in combination with a mechanical assembly, allows linear movement in both directions (forward and backward) of the gripper (P) of the support arm tool (C). The cam axis (lOb), for another suitable profile, allows in combination with two separate mechanical assemblies, on the one hand the raising and lowering of the tool-carrying arm (C) and, on the other hand, the rotation da a horizontal plane of said arm (C), these two movements being sepia res.

 For this purpose, the first groove <îOa) cam-shaped c father with a roller (11) integral with a rack (12) mounted to slide freely on two parallel guides (13 and 14). The 1st crema (12) meshes with a pinion (15) integral with a rotated shaft (16) at the end of which is vertically mounted a plate (17) which has, in the manner of a crankshaft.

 Indeed, the plate (17) has near its circular bor a roller (18) which acts in a groove (19a) formed by a squared branch (19b) of a rack (19) mounted with free sliding along one or more guides (20) arranged parallel to the guides (13 and 14) of the rack (12) (Figure 13). I1 results in an alternating movement of the rack (19) during the rotation of the plate (17).

 The rack (19) cooperates with a toothed pinion (21) mounted to rotate freely on a vertical shaft (22) arranged at the end to act on the clamp (P) of the tool-carrying arm (C). The pinion (21), via satellites (23) rotates the control shaft (22) for the linear movement of the clamp (P), in one direction or the other depending on the direction for rotation of the shaft C22) subject to the movement of the rack (19) For this purpose, the shaft (22) is secured at the end of a pinion (24) which cooperates with a crema # i1lère (25) formed on the body of the clamp mounted to slide guided in a protective casing (26) (Figures 1 and 11).

 It is pointed out that the shaft (22) is mounted to slide freely inside a sheath (22a) fixed in translation, part of the bore of the sheath (22a) being splined to cause said shaft (22) to rotate. which is hollow in its upper part for housing a compensation spring (R) hung at the end of the sheath (22a).

 The second groove profiled in cam (lOb), cooperates in the same way as the groove (lova), with a roller (27) secured to a rack (28) mounted to slide freely on the two guides pa parallel (13 and 14). The rack (28) meshes with a pinion (29) integral with a rotating shaft (30) at the end of which is mounted vertically a crankshaft plate (31) disposed in the same plane and next to the plate (17).

As before, the plate (31) has, near its circular edge, a roller (32) which acts in a groove (33a) formed in a squared branch (33b) of a rack (33) mounted to slide freely along guides (34) arranged parallel to the guides (20) and in the same vertical plane (Figure 11). The 1st rack (-33) meshes with a circular toothing (35) formed
at the periphery of a sleeve (36) rotatably mounted on the control shaft (22).

 The bore of the sleeve (36) has internally a toothed ring (37) which, by means of the satellites (38), whose axes are fixed to the frame, acts in rotation on a sleeve (39) in which is mounted the control shaft assembly (22) sheath (22a). The sheath (39) has grooves (39a) to allow the rotation of a hollow vertical axis (40) suF carrying the tool holder arm (C).

 It is emphasized that the bore of the sleeve (36) also has internally in the upper part, another toothed ring (41? Capable of cooperating with the satellites (23).

 According to another important characteristic of the invention, the second profiled cam groove (lob) cooperates with a second roller (41) integral with another rack (42). This roller (41) occupies an angular position (ct) determined relative to the roller (27) (Figure 11) to allow to obtain in combination with the profile of the cam (10b), the two separate movements as indicated above.

 The rack (42) is mounted to slide freely on guides (43) and cooperates with pinion (44) to drive in rotation on a half-turn, a crankshaft plate (45) equipped with a roller (46) which acts in a groove (47a) of a square guide (47) mounted sliding guided along a column (48) (Figure 13) This guide is coupled to the upper part of the support axis (40) being mounted free in rotation on said axis (Figure 11).

 It therefore follows that the partial rotation drive of the crankshaft plate (45) has the effect of controlling the displacement in height (descent and ascent) of the support axis (40) of the arm via the guide (47 ).

 It is emphasized that the different crankshaft plates (17, 3: and 45) are suitably determined to make a U-turn so that, at uniform speed of rotation of the different pinions, oi has an acceleration period and an elation period, which results in smooth operation.

 It is now necessary to analyze the operation by referring more particularly to FIGS. 2 to 9 of the drawings.

 It will be recalled that the phases shown in these figures relate to the tool extraction cycle (o) from the magazine with a view to placing it in the spindle (b) of the machine tool (Mo). It is obvious that the principle is the same for the reverse cycle where only the direction of rotation of the motor is different.

 After determining the desired tool, a position control allows the tool-carrying arm and the chosen tool (o) to be brought into axial alignment (Figure 2). In this original position, the clamp is retracted, the vertical axis (40) of the support arm is not lowered.

 In the phase of FIG. 3, the drum (10) being driven in rotation, in one direction, by the motor (8), first controls the movement of the clamp (P) which comes to grip the tool.

The profiled cam (10a), in combination with the roller (11), controls rotation, on a half-turn via the rack and pinion assembly (12) - pinion (15), the crankshaft plate (17) which allows the reciprocating movement of the rack (19) to act in rotation on the control shaft (22) - sleeve assembly
(22a) via a pinion assembly (21) - satellite (23).

The pinion (24) of the shaft (22) drives the rack (25) of the body of the clamp for its deployment.

 In the phase shown in FIG. 4, the cam (10b), in combination with the roller (41), has controlled in one direction by the rack (43) and the pinion (44), the crankshaft plate (45) to act on the guide (47) for the descent of the vertical support axis (40) of the tool holder arm. The tool (o) is released from the magazine (M).

 In FIG. 5, the profiled cam (lova), in combination with the roller (11), continues to act on the crankshaft plate (7) which controls the movement of the rack (19) in a direction directly opposite to that of the Figure 3. The shaft assembly (22) - sleeve (22a) is therefore driven in the opposite direction, so that the pinion (24) and the rack (25) allow the withdrawal of the body of the clamp (P).

 In FIG. 6, the cam (lob) in combination with the roller (27) controls the rack (28) to act in rotation on the crankshaft plate (31) via the pinion (29). The plate (31) allows movement in one direction of the rack (33) for the limited rotation drive of the sleeve (39) and consequently of the support axis (40) of the arm. The tool is positioned opposite the machine (MB).

 In FIG. 7, the cam (10a) in combination with the roller (11) acts again on the crankshaft plate (17) as indicated in the phase of FIG. 3 to authorize the deployment of the clamp (P) in view of the axial positioning of the tool (o) under the spindle (b) of the machine (Mo).

 Figure 8 shows the tool coupling of the machine spindle. For this purpose, the cam (10b) in combination with the roller (ol) controls in the opposite direction to that of FIG. 4, the crankshaft plate (45) which ensures, via the guide (47), the ascent of the entire tool holder arm.

 In Figure (9), the clamp (P) is again removed and released from the tool which remains coupled to the spindle of the machine (Mo). The cam (loua) in combination with the roller (11) acts on the crankshaft plate (17) as shown in Figure 5.

 The cam (10b), with the roller (21), continues to act on the crankshaft plate (31) in a direction opposite to that of the figure for the rotary drive of the support arm with a view to bringing it back to the position d 'origin.

 It is obvious that this preset cycle is carried out during one complete revolution of the drum (.10).

 In an alternative embodiment, provision is made to replace the profiled cam grooves with # crémai1lères cylinders which act.

feels directly on the various pinions relating to the mechanical assemblies for the linear movement in both directions of the gripping pliers and for the raising and lowering of the tool holder arm on the one hand, and the rotation in a horizontal plane of said bra somewhere else.

 The advantages emerge clearly from the description, in particular it is emphasized that the constraints of electrical connection with the machine are reduced. It is not necessary to control each movement. The enslavements are reduced.

 Finally, we note that the manipulator block can have either a single gripping arm. In this case, only the coding of the location of the tool is necessary, the tool being always returned to the same location, that is to say two arms. In this second case, the loading time of the tools is very short, but it is necessary to continuously memorize their position in the magazine. The exchanger-machine link must take account of the memory of the rmic command.

Regarding the control of the magazine positions relative to the exchanger block, different solutions are possible pc convert the coded indication of the number of tools under the numerical control of the machine in order to ensure the chosen positioning of the tool of the magazine in axial alignment with the exchanger arm, then the control of the exchange drive motor #
The invention is in no way limited to that of its modes of appli # ation any more than to those of the embodiments of its various parts having been more particularly indicated, on the contrary it embraces all variants.

Claims (14)

-1- Automatic tool changer device for machine tools essentially comprising a rotary magazine for positioning the tools and a manipulator block equipped with at least one tool-carrying arm with gripper, characterized in that said manipulator is subject to a member for controlling the rotation of a drum which has arrangements or means, one of said arrangements C or means, in combination with a mechanical assembly, allows the linear displacement in both directions (forward and backward) of the gripper ( P) of the tool-carrying arm (C), the other arrangement or means allowing, in combination with two separate mechanical assemblies, on the one hand the raising and lowering of the tool-carrying arm (C) and, on the other hand , the rotation in a horizontal plane of said arm (C), these two movements being separated; the drum rotation control member and the magazine control member being subjected to a position control. -2- Device according to claim 1, characterized in that the drum has peripherally at least two grooves of profile de-: finished forming cam #, one of said cams (lova), by a suitably suitable profile and in combination with l mechanical assembly, allows linear movement in both directions (forward and backward) of the gripper (P) of the tool arm (C), the other cam (10b), by another suitable profile allowing in combination with the two separate mechanical assemblies, on the one hand the movement and the descent of the tool-carrying arm (C) and, on the other hand, the rotation in a horizontal plane, of said arm (C), these two movements being separated. -3- Device according to claim 2, characterized in that the first groove (lOa) cam-shaped cooperates with a rolling member (11) integral with a rack (12) slidably mounted on parallel guides (13 and 14 ), said rack (12) driving in rotation a plate (17) which acts like a crankshaft. -4- Device according to claim 3, characterized in that the plate (17) has near its circular edge a rolling member (18) which cooperates with a groove (19a) relating to a part (19b) of a rack (19) slidably mounted on guides (20) arranged parallel to the guides (13 and 14), said rack (19) being driven in an alternating movement during the rotation of the plate (17). -5- Device according to claim 4, characterized in that the rack (19) cooperates with different drive members (21 23) for the rotation of a vertical control shaft (22) arranged at the end for linear movement in translation of the body of the clamp, in one direction or the other, depending on the direction of rotation of the shaft (22) subject to the alternating movement of the rack (19). -6- Device according to any one of claims 2 and 3, characterized in that the profiled cam groove (lob), cooperates with a rolling member secured to a rack (28) slidably mounted on the guides (13 and 14) of the rack (12), said rack (12) driving in rotation a plate (31) which acts like a crankshaft. -7- Device according to claim 6, car-actuated in that the plate (31) has near its circular edge a rolling member (32) which cooperates with a groove (33a) relating to a part (33b) d 'a rack (33) slidingly mounted on guides (34), said rack being driven by an alternating movement during the rotation of the plate (31). -8- Device according to claim 7, characterized in that the rack (33) cooperates with different drive members (35, 36, 37, 38) to act in rotation on a sleeve (39) in which lc is mounted l 'control shaft (22), said sheath (39) taking arrangements to allow the rotational drive c a hollow vertical axis (40) supporting the tool holder arm (C). -9- Device according to any one of claims 2 to 8, characterized in that the profiled groove (10b) cooperates with another rolling member (41) integral with a rack (42) slidably mounted on guides (43 ), said rack driving in rotation a plate (45) which acts like a crankshaft. -10- Device according to claim 9, characterized in that one rolling member (41) occupies relative to the rolling member (27) an angular position (o () determined to obtain, in combination with the profile the cam (lOb), the two separate movements.  tool holder arm. -11- Device according to claim 9, characterized in that the plate (45) has near its circular edge, a rolling member (46) which acts in a groove (47a) of a guide (47) coupled to the upper part of the support axis (40), with a view to lowering or raising the assembly of the support axis (40) of the -12- Device according to any one of claims 1 and 2, characterized in that the magazine (M) is integral with a central shaft arranged vertically and on which is mounted free in rotation a console (4) supporting a gearmotor < MR) shaped and arranged to drive the magazine, the rotation of which is controlled by an electronic member subject to the position control.  -13- Device according to any one of claims 1 to 12, characterized in that the entire magazine (M) with its manipulator (B) is mounted on a common support base easily movable to be adapted to a machine- any tool. -14- Device according to any one of claims 1 - 13, characterized in that, alternatively, the profiled cam grooves are replaced by # cylinderscracking which act directly on the mechanical assemblies.