JPS63105853A - Automatic tool exchanger - Google Patents

Abstract

PURPOSE:To enable a sliding speed or the like to be increased to a high speed and the exchange time of a tool to be reduced, by providing a guide mechanism which restricts a moving direction of a sliding member, connected to a sliding cylinder, setting the sliding member to a predetermined position. CONSTITUTION:A swing arm 21 turns 90 deg. with a fixed swivel center P serving as the center by driving a swiveling cylinder 25, while a turning cam 73 is turned 90 deg. through a turning center shaft 78 and a cas driving mechanism 80. While a sliding member 31 is turned by the minimum radius with a connection part 64 serving as the center because the connection part 64 of a connecting bracket 61 is stopped by a piston rod 63 of a sliding cylinder 62. When the swing arm 21 swivels, the cam driving mechanism 80, smoothly turning the center line of a cas follower 78 drawing a locus of almost tear shape while rotating the turning can 73 by 90 deg., moves the sliding member 31 along a guide way 22.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an automatic tool changer for changing tools between a spindle and a tool magazine of a machine tool such as a machining center or a boring machine.

[Background technology and its problems]

Conventionally, various types of automatic tool changers have been developed depending on the type, size, etc. of machine tools. By the way, in the case of a large-sized machine tool, the axis of the spindle and the axis of the tool pot of the tool magazine do not necessarily coincide, and may deviate, for example, by 90 degrees.

In such a case, in the automatic tool changer, the tool change arm unit itself, which includes the tool change arm, needs to slide or rotate to accommodate the axis deviation. In this case, in the conventional device, the sliding and turning drive mechanism of the unit is provided in the tool exchange arm unit itself, which results in an increase in size and weight of the tool exchange arm unit.

Therefore, there is a problem that the moment of inertia of the tool changing arm unit becomes large, making it impossible to increase the sliding and swinging speeds, and furthermore, there is also the problem that the tool changing arm has poor accessibility to the machine tool and the tool magazine. Ta.

[Purpose of the invention]

An object of the present invention is to reduce the tool exchange time by reducing the size of the tool exchange arm unit and increasing the sliding and swinging speeds in an automatic tool changer.

[Means and effects for solving the problems] The present invention has the following features:
A swing drive mechanism is provided for swinging a swing member having a fixed swing center at a predetermined angle, and a sliding member is supported on the swing member so as to be slidable in a linear direction; A tool changing arm unit having a tool changing arm and an arm drive mechanism is supported, and the spin rod end side of a sliding cylinder that is swingably supported by a fixed part is rotatably attached to a sliding member. can be slidably driven relative to the swinging member, and furthermore, when the swinging member is driven to swing by the swinging drive mechanism, the moving direction of the sliding member connected to the sliding cylinder is regulated to keep the sliding member in a predetermined position. It is constructed by providing a guide mechanism to set the position.

As a result, at least the sliding cylinder that slides the tool changing arm unit is supported by a fixed part separate from the sliding member, thereby reducing the weight of the tool changing arm unit, reducing the moment of inertia, and increasing the speed of operation. The aim is to achieve the above objective.

Further, the swing drive mechanism is constituted by a swing cylinder supported by a swing member outside the swing member, and the tip side of the piston rod of the swing cylinder is rotatably connected to the swing member. For example, the second swing drive mechanism is also supported by a separate part from the tool exchange arm unit, which makes it possible to further reduce the weight of the tool exchange arm unit, thereby better achieving the above object.

〔Example] Hereinafter, one embodiment of the present invention will be described based on the drawings.

In FIGS. 1 and 2 showing the overall configuration and FIG. 3 showing the main configuration, a machine tool 10 such as a machining center is equipped with a spindle 11, and an example of this machine tool 10 is provided with a tool magazine 15. A large number of tool pots 16 having axes perpendicular to the axis of the spindle 11 are stored in the tool magazine 15 and can rotate on orbits within the tool magazine 15. A swing center shaft 18 is rotatably supported on the frame 17 (see FIG. 2) of the tool magazine 15, and the swing center shaft 18 has a fixed swing center P, with the axis of the center shaft 18 being a fixed swing center P. A swing arm 21 as a swinging member is fixed so as to be integrally rotatable. The swing arm 21 is formed in a planar shape, and two guideways 22, upper and lower, are integrally provided on one long side of the L-shape at a predetermined distance apart. Further, at the L-shaped bent portion of the swing arm 21, the tip of a spittoon rod 26 of a swing cylinder 25 serving as a swing drive mechanism is rotatably connected via a connector 24. This swinging cylinder 25 is swingably supported by the tool magazine frame 17 by a trunnion center shaft 27 at the center of the cylinder.

Therefore, when this swing cylinder 25 is operated, the swing arm 21 swings about the fixed swing center P, and can swing approximately 90 degrees from the solid line position in FIG. 1 to the chain line position. .

A sliding member 31 of a tool exchange arm unit 30 is supported by the guideway 22 of the swing arm 21 so as to be slidable in the horizontal direction. This sliding member 31 has a pivot shaft 3.
2 is rotatably supported, and a pinion 33 is integrally fixed in the middle of this pivot shaft 32. This pinion 33
A rack 34 supported vertically movably by the sliding member 31 is engaged with the rack 34, and this rack 34 is connected to the arm rotation cylinder 3 attached to the upper surface of the sliding member 31.
5 is attached to the piston rod 36 of the cylinder 35.
As the pinion 33 is driven, the pinion 33 and, in turn, the pivot shaft 32 are driven to pivot.

Here, the pinion 33, the rack 34, and the arm rotation cylinder 35 constitute an arm rotation drive mechanism 37. Incidentally, reference numeral 38 is a stopper of the rack 34 provided on the sliding member 31 at a position below the rack 34.

A piston 42 having a piston rod 41 is housed inside the pivot shaft 32 on the side protruding from the sliding member 31, so that the protrusion end side of the pivot shaft 32 functions as a so-called cylinder casing. There is. Further, air supply holes 43.44 are provided in the central shaft portion on the pinion 33 side and the side surface on the other end side of the pivot shaft 32, and the piston 42 is moved by supplying compressed air to these air supply holes 43.44. It is designed to advance and retreat. Here, the protruding end of the pivot shaft 32, the piston loft 41, and the piston 42 constitute an arm advance/retreat drive mechanism 45, and the arm advance/retreat drive mechanism 45 and the arm rotation drive mechanism 37 constitute an arm drive mechanism 47. has been done.

One end of an arm interlocking member 52 is fixed to the tip of the piston rod 41 protruding from the pivot shaft 32 via a connecting plate 51, and this arm interlocking member 52 is attached to the outer periphery of the pivot shaft 32 via a spline 53 in the axial direction. It is slidably and non-rotatably supported.

A tool exchange arm 5 is provided at the other end of this arm interlocking member 52.
4 is fixed, and tool gripping portions 55 are formed at both ends of this tool exchange arm 54, respectively. Therefore, the tool exchange arm 54 is moved in the axial direction of the rotation shaft 32 by the operation of the arm forward/backward drive mechanism 45, and is also rotated around the rotation shaft 32 by the operation of the arm rotation drive mechanism 37, so that the tool exchange arm 54 can be moved in the axial direction of the rotation shaft 32 by the operation of the arm forward/backward drive mechanism 45, and rotated around the axis of the rotation shaft 32 by the operation of the arm rotation drive mechanism 37. It is now possible to perform exchange operations.

Here, the tool exchange arm unit 30 is constituted by members indicated by a series of symbols from the sliding member 31 to the tool gripping portion 55.

One end of a connecting bracket 61 is fixed to the lower end of the sliding member 31, and the lower bent portion of the other end of the connecting bracket 61 has a connecting portion in which a piston rod 63 of a sliding cylinder 62 can be driven. 64. The approximate center of this sliding cylinder 62 is the trunnion shaft 6
5 and is swingably supported by a trunnion bracket 66, and this trunnion bracket 66 is attached to a bracket 67 as a fixed part fixed to the tool magazine frame 17. Therefore, the sliding cylinder 6
2 is driven, the sliding member 31 is horizontally slid along the guideway 22 via the connecting bracket 61.

A camshaft 72 is rotatably supported by the bracket 67 as the fixed part via a bearing member 71, and a disk-shaped rotating cam 73 is integrally connected to the upper end of the camshaft 72. . As shown in FIG. 4, this rotary cam 73 has a guide surface 74 formed from a substantially T-shaped groove on its upper surface, and the center of the one-shaped branch of this guide surface 74 is located at the center of the camshaft 72. The center is made equal to the center of rotation of the rotation cam 73. Further, a fixed cam 75 is arranged above the rotating cam 73, and this fixed cam 75 is fixed to the bearing member 71. This fixed cam 75 is formed into a sub-curve shape, and has an L-shaped guide surface 76 formed inside thereof. The center of the L-shaped bent portion of the guide surface 76 is made equal to the center of rotation of the rotation cam 73,
In addition, this guide surface 76 always remains on the L-shaped guide surface 76 side of the T-shaped groove 74 even when the rotating cam 73 is rotated 90 degrees as shown in FIGS. 4(A) and 4(B). The sides located in are made to almost match. A cam follower 78 rotatably supported at the lower end of the connecting bracket 61 is engageable with the guide surfaces 74 and 76 of the rotary cam 73 and the fixed cam 75, and the guide surface 74 and 76 of the rotating cam 73 and the fixed cam 75 are engaged with each other. A cam follower 78 located at the center of the branching part of the surface 74 can slide in the vertical direction indicated by the arrow, while a cam follower 78 located at the center of the branching part of the guide surface 74 in FIG. It is designed to be able to slide in the horizontal direction shown by the arrow. Here, the position where the camshaft 72 is provided is, as shown in FIG. Position 6 where the connecting portion 64 at the tip of the piston rod 63 is located when the piston rod 63 is positioned in the direction passing through the fixed rotation center P.
It is set to 4A.

A first toothed wheel (sprocket) 81 is fixed to the lower end of the rotation center shaft 18 of the swing arm 21, and the same as the first toothed wheel 81 is fixed to the lower end of the camshaft 72. A second toothed wheel 82 having the number of teeth and shape is fixed, and a chain 83 serving as a rotation transmission means is hooked between the first and second toothed wheels 81, thereby rotating the swing arm 21. The first toothed wheel 81 and the chain 8
3, the second toothed wheel 82 is rotated, and the rotating cam 73
is also rotated so that the position of the T-shaped guide surface 74 is as shown in FIG.
), (B). Here, a cam drive mechanism 80 is constituted by the first and second toothed wheels 81 and 82 and the chain 83, and this cam drive mechanism 80 and a series of members with reference numbers from the bearing member 71 to the cam follower 78. This constitutes a guide mechanism 70 that restricts the moving direction of the sliding member 31 and sets the sliding member 31 at a predetermined position.

Next, FIG. 6(A) shows the operation of this embodiment.

This will be explained with reference to (Dan) and FIG.

In the states of the swing arm 21 and the tool changing arm 30 shown in solid lines in FIGS. 1, 2 and 6(A), the piston rod 26 of the sliding cylinder 25 and the piston rod 63 of the sliding cylinder 62 are both inside the casing. The swing arm 21 is in a retracted and contracted state.
is swung toward the tool magazine 15, and the sliding member 31 is located on the right side of the swing arm 21 in FIG. This position is the standby position or initial position of the tool exchange arm 54, and the tool exchange arm 54 in this state is shown at 54A.

When a predetermined tool pot 16 of the tool magazine 15 is indexed to the left position of the tool exchange arm 54A while the tool exchange arm 54 is in the standby position, the sliding cylinder 62 is actuated and the piston rod 63 advances. is,
The sliding member 31 is moved to the left in FIGS. 1 and 2 via the connecting bracket 61, and the tool gripping portion 55 on the left side of the tool changing arm 54 grips a tool (not shown) in the tool bot 16. It will be stopped in a state where The tool exchange arm 54 in this state is represented by 54B.

Next, compressed air is supplied to the air hole 43 of the arm forward/backward drive mechanism of the tool change unit 30, and when the piston rod 41 is driven in the direction of protruding from the pivot shaft 32 via the piston 42, the arm interlocking member 52 is moved. The tool exchange arm 54 is moved downward from the position 54B in FIG. Move to position 54C shown.

Thereafter, when the sliding cylinder 62 is driven in the direction in which the piston rod 63 contracts (retreats) and the sliding member 31 is moved to the right, the tool exchange arm 54 moves to the position indicated by 54D.

Next, when the piston rod 41 of the arm forward/backward drive mechanism is moved in the direction of recessing into the pivot shaft 32, the arm 54
returns to the initial position indicated by 54A (solid line position in FIG. 6(A)).

After the new tool is supported on the tool gripping portion 55 on the left side of the arm 54 in this way, the swinging cylinder 25
is driven in the direction in which the piston rod 26 advances;
The piston rod 63 of the sliding cylinder 62 is maintained in a retracted state.

At this time, the connecting portion 64 at the tip of the piston rod 63 of the sliding cylinder 62 moves to the initial position again and is attached to the T-shaped guide surface 74 of the rotating cam 73 as shown in FIG. 4(A).
As shown, it enters from the upper groove and is located at the intersection.

The swing arm 2 is driven by this swing cylinder 25.
1 rotates 90 degrees around a fixed rocking center P, and a rotating cam 73 rotates around a rotating center shaft 18 and a cam drive mechanism 8.
0 through 90 degrees in the direction of the arrow in FIG. 4(A), resulting in the state shown in FIG. 4(B). On the other hand, the sliding member 31 is
Since the connecting portion 64 of the connecting bracket 61 is stopped by the piston rod 63 of the sliding cylinder 62 at the position shown by the solid line in FIG. . Therefore, the sliding member 31
is the slideway 2 as the swing arm 21 swings.
2, and is moved from the right end side to the left end side of the swing arm 21, and reaches the position shown by the chain line in FIG. 6(A).

When swinging the swing arm 21, the cam drive mechanism 80 smoothly swings with the center line of the cam follower 78 drawing a substantially slanted trajectory Q, as shown in FIG. is rotated by 90 degrees in Figure 4 (B
), the sliding member 31 moves extremely smoothly along the guideway 22. ·On this occasion,
Assuming that the guide mechanism 70 is not provided, in FIG. 5, the tip connecting portion 64 of the piston rod 63 is at the most retracted position ff64A, and it is not clear whether the movement is upward or to the right in the figure. Although it is inconvenient that an extremely large stress is applied between the sliding member 31 and the swing arm 21, such a problem does not occur because the guide mechanism 70 smoothly changes direction as described above.
Since the piston rod 63 of the sliding cylinder 62 is not operated in the advancing direction at the same time as the swing cylinder 25 is operated, the sliding member 31 rotates at a minimum around the connecting portion 64 as shown by the chain line in FIG. 6(A). In addition to changing direction by 90 degrees in radius, the sliding member 31 automatically moves to the left end side of the swing arm 21 and moves to the side of the spindle 11 when the tool exchange arm 54 performs an F-g exchange operation with the spindle 11. This is a convenient position for inserting the tool exchange arm 54 into the tool, and no process loss occurs.

In this way, the swing arm 21 and the sliding member 3
1 is swung to the state shown in FIG. 6(B),
Once the tool exchange arm 54 is at the position indicated by 54E, the piston rod 3 of the piston rod 62 of the sliding cylinder 62 is driven in the advancing direction, and the sliding member 3
1 is moved to the right end side of the swing arm 21, the arm 54 is moved to the right side, and therefore the spindle 1 is moved by the tool gripping portion 55 on the right side of the arm 54.
The heavy tool previously attached to 1 is engaged, and the
The state shown by 4F will be reached.

In this state, the piston rod 41 of the arm advancement/retraction drive mechanism 45 is advanced, and the tool exchange arm 54 is moved from the spindle 11
The spindle 11 is moved in a direction away from the spindle 11 to pull out the heavy tool, and is moved to a position indicated by reference numeral 54G.

Next, the cylinder 35 of the arm rotation drive mechanism 37 is activated, the pinion 33 is rotated 180 degrees via the rack 34, and the old and new tools on the arm 54 are exchanged 180 degrees, so that the new tool that was initially on the left side is now on the right side and now on the right side. The heavy tools that were there were moved to the left. In this state, the arm forward/backward drive mechanism 4
The piston rod 41 of 5 is retracted, and the tool exchange arm 5
4 is again in the position indicated by reference numeral 54F, and a new tool is mounted on the spindle 11.

Next, the sliding cylinder 62 moves its piston rod 63
The arm 54 is moved downward in FIG. 1 and is again positioned at 54H. In this state, the swing cylinder 25 is moved in the direction in which its piston rod 26 is contracted, and the tool change arm unit 30 is returned to the initial standby position shown by the solid line in FIG. 1.2 and FIG. 6(A). The state is maintained until the next operation command. At this time, the operation of the guide mechanism 70 smoothly rotates the connecting portion 64 as described above, but the rotation direction of the rotation cam 73 at this time is as shown in FIG. 4(B). The direction is opposite to that described above, as indicated by the arrow.

On the other hand, the spindle 11, which has been replaced with a new tool, enters the next machining process and performs a predetermined machining operation.

Thereafter, when the next tool exchange command is issued, the above-described operations are repeated to perform seven sequential tool exchanges and predetermined machining is performed.

According to this embodiment as described above, there are the following effects.

That is, by not operating the sliding cylinder 62 when swinging the swing arm 21, the sliding member 31 can be held at the shortest position to the fixed swing center P of the swing arm 21. swing arm 21
The moment of inertia during swinging can be reduced, the swinging speed can be increased, and the stress applied to the swing arm 21 and the like can be reduced. In addition, this sliding member 31
Maintaining the shortest position to the fixed swing center P allows the tool changing arm unit 30 to maintain a position that is efficient for the tool changing operation on the spindle 11 side, and from this point as well, the tool changing operation can be speeded up. Furthermore, when the position of the sliding member 31 is maintained due to the non-operation of the sliding cylinder 62, the position of the connecting portion 64 of the piston rod 63 of the sliding cylinder 62 to the sliding member 31 side is different from that of the movable cam 73 and the fixed cam 75. Since the position is regulated by the guide mechanism 70 consisting of
The swinging motion of the swing arm 21 can be performed extremely smoothly, and no unnecessary stress or the like is applied. Furthermore, since the swinging cylinder 25 and the sliding cylinder 62 are supported on a fixed part separate from the swinging swing arm 21, the weight of the tool changing arm unit 30 can be reduced, and from this point of view, high-speed operation is possible. In addition, since the cylinder 25 is used for the swinging drive mechanism of the swing arm 21, the structure becomes simple and control becomes easy.
The cost of the device can be reduced. Furthermore, the sliding cylinder 6
The guide mechanism 70 that regulates the position of the connecting portion 64 of the second piston rod 63 includes a rotating cam 73 having a T-shaped guide surface 74 and a fixed cam 7 having an L-shaped guide surface 76.
5 or the like, sufficient position regulation can be achieved with a relatively simple structure, and from this point of view as well, the cost of the apparatus can be reduced.

Furthermore, since the cam drive mechanism 80 of the guide mechanism 70 has a simple structure consisting of the first and second toothed wheels 81, 82 and the chain 83, the cost can also be reduced. Further, the arm drive mechanism 4 of the tool exchange arm 54
Reference numeral 9 indicates an arm drive mechanism 37 consisting of a piston 33 and a rack 34, and a cylinder-type arm advance/retreat drive mechanism 45.
Since it is constructed from the above, there is no longer a structure in which the binion 33 slides in the axial direction with respect to the rack 34 as in the conventional device, and the mechanism can be simplified and made smaller. The overall size can be reduced and the accessibility to the tool magazine 15 and the spindle 11 of the machine tool 10 can be improved. In addition, as described above, the sliding member 3
1 rotates with an extremely small radius when the swing arm 21 rotates, the splash cover and the like for covering the entire tool changer can also be made smaller.

In carrying out the invention, the present invention is not limited to the above embodiments, and the present invention includes modifications within the scope of achieving the object of the present invention. For example, the swing drive mechanism does not need to be the swing cylinder 25 as in the above embodiment, and may be a swing drive source such as an electric motor or a rotary hydraulic actuator. However, if it is a cylinder type, It has the advantages mentioned above. Further, the guide mechanism 70 of the connecting portion 64 of the piston rod 63 is not limited to the structure using the rotary cam 73 etc. as in the above embodiment, but may have another structure. The structure is not limited to the two toothed wheels 81 and 82 and the chain 83 connecting them, but may also be connected by gears.Furthermore, the shape of the tool gripping part 55 of the tool changing arm 54 is such that it can move in a linear direction to remove the tool. The structure is not limited to one that grips the tool, and may be one that grips the tool by rotating, but as long as it moves in a straight line and grips the tool, as in the above embodiment, each tool change operation will be made more efficient. It has the advantage of being easy to perform.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to downsize the tool changing arm unit in an automatic tool changing device, increase the sliding speed, swing speed, etc., and shorten the tool changing time.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which Fig. 1 is a partially sectional plan view, Fig. 2 is a partially sectional front view of Fig. 1, and Fig. 3 is a schematic diagram of the main parts. A perspective view showing the configuration, FIGS. 4(A) and 4(B) are plan views showing different operating states of the rotary cam and the fixed cam, FIG. 5 is a plan view showing the operating states of the sliding cylinder, and FIG. 6 (A) and (B) are schematic plan views showing the operating states of this embodiment, and FIG. 7 is a plan view showing the operating states of the cam followers in the rotary cam and the fixed cam. 10...Machine tool, 11...Spindle, 15...
- Tool magazine, 16... Tool pot, 21... Swing arm as a swinging member, 25... Swinging cylinder as a swinging drive mechanism, 26... Piston rod, 30... Tool exchange Arm unit, 37... Arm rotation drive mechanism, 45... Arm advance/retreat drive mechanism, 47
...Arm drive mechanism, 54...Tool exchange arm, 6
2...Sliding cylinder, 63...Piston rod,
64... Connecting part, 67... Bracket as a fixed part, 70 φ guide mechanism, 73... Rotating cam, 74
... Guide surface, 75 ... Fixed cam, 76 ... Guide surface, 78 ... Cam follower, 80 ... Cam drive mechanism, 81 ... First toothed wheel, 82 ... No. 2 toothed wheel, 83... chain as rotation transmission means, P.
・Fixed swing center.

Claims (4)

[Claims] (1) An automatic tool changer that exchanges tools between the spindle of a machine tool and a tool magazine, which includes a swinging member having a fixed swinging center and a swinging drive that swings the swinging member at a predetermined angle. a mechanism, a sliding member supported by the swinging member so as to be slidable in a linear direction, a tool exchange arm supported by the sliding member, and an arm drive mechanism that provides a predetermined drive to the tool exchange arm. a tool exchange arm unit, a sliding cylinder that is supported by a fixed part so as to be vibrating, and whose piston rod end side is rotatably attached to the sliding member, and which slides the sliding member relative to the swinging member; A guide mechanism that regulates the moving direction of the sliding member connected to the sliding cylinder and sets the sliding member at a predetermined position when the swinging member is driven to swing by the swinging drive mechanism. Automatic tool changer. (2) In claim 1, the swing drive mechanism is a swing drive mechanism that is swingably supported on the outside of a swing member and has a piston rod end side rotatably connected to the swing member. An automatic tool changer characterized in that it is composed of a dynamic cylinder. (3) In claim 1 or 2, the guide mechanism includes a fixed cam having an L-shaped guide surface, and is provided so as to be able to be driven while being overlapped with the fixed cam, and the guide mechanism has an L-shaped guide surface. A rotary cam having a T-shaped guide surface whose rotation center is equal to the center of the bending part of the guide surface and which is branched at this rotation center; The cam drive mechanism is attached to the connecting portion between the piston rod of the sliding cylinder and the sliding member, and is engaged with the L-shaped guide surface of the fixed cam and the T-shaped guide surface of the rotating cam, respectively. An automatic tool changer comprising a cam follower. (4) In claim 3, the cam drive mechanism has a rotation center coaxial with a fixed rocking center of the swinging member, and a first toothed mechanism that is integrally fixed to the swinging member. A second toothed wheel having a rotation center coaxial with the rotation center of the rotation cam and integrally fixed to the rotation cam, and these first and second toothed wheels are interlocked. An automatic tool changer characterized in that it is configured to include a rotation transmission means for rotating the tool.