JPH0533242Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention relates to an automatic tool changer for machine tools.
More specifically, the present invention relates to an automatic tool changer having an opening/closing mechanism for a splash guard cover disposed between the tool change arm of the automatic tool changer and the main shaft of a machine tool.

[Conventional technology]

Traditionally, machine tools have been equipped with automatic tool changers, which include a tool changer arm for changing tools between the main spindle of the machine tool and a tool preparation means such as a tool magazine. It was hot. Furthermore, to protect the tool magazine of the automatic tool changer and the tool change arm from chips and cutting fluid during machining, a splash guard cover is placed between the tool change arm and the main shaft of the machine tool.
The cover disposed between the tool exchange arm and the spindle is closed during machining, and opened to allow the tool exchange arm to approach the spindle when exchanging tools. Therefore, a mechanism for opening and closing the cover is required. A conventional cover opening/closing mechanism is operated by a dedicated actuator, and after detecting that the cover is actually opened during a tool change, the tool change arm starts operating.

In this way, the cover opening/closing mechanism that has a dedicated actuator needs to detect that the cover is actually opened, so it takes time to start the operation of the tool exchange arm, and therefore the tool exchange time cannot be shortened. There was a problem. In order to solve this problem, it is necessary to be able to perform the cover opening operation and the tool exchange arm operation almost simultaneously. For example, Japanese Utility Model Application Publication No. 63-57039 provides an upward swing opening type door (cover) or a double door type door with a return spring, and the door is pushed open when a linear motion type magazine base moves forward. An opening/closing mechanism is disclosed.

[The problem that the idea attempts to solve]

As described above, in the case of a linear motion type magazine base, the door (cover) can be configured to be pushed open during its forward motion. However, when using a rotating tool changing arm, it is difficult to use such a push-open door (cover). Although it is not impossible to open and close the door (cover) using a rotating tool exchange arm,
This requires a complex link mechanism.

In the case of a swivel-type tool exchange arm, the tool exchange arm rotates once toward the spindle to remove the tool on the spindle from the standby position, rotates to exchange the old and new tools, and then swings again to return to the standby position. is necessary. The cover must be opened during the first pivot of the tool change arm, then kept open during the next pivot of the tool change arm, and closed during the final pivot. As described above, when the movement of the tool exchange arm becomes complicated, there is a problem in that it becomes increasingly difficult to open and close the cover in conjunction with the tool exchange arm.

The purpose of this invention is to solve these problems and
To provide an automatic tool changer having a simple structure and having a cover opening/closing mechanism that does not adversely affect tool change time.

[Means to solve the problem]

The automatic tool changer according to the present invention includes a first actuator that rotates the tool change arm between a standby position and a tool gripping position, a cover opening/closing mechanism connected to the first actuator, and a cover opening/closing mechanism connected to the first actuator. The cover is opened in synchronization with the rotation of the tool changing arm from the standby position to the tool gripping position, and the cover is closed in synchronization with the rotation of the tool exchange arm from the tool gripping position to the standby position. More specifically, in an automatic tool changer in which a tool exchange arm having tool grippers at both ends exchanges tools between a tool spindle and a tool stocker of a machine tool by a rotating operation, the tool exchange arm performs tool exchange. a first actuator that rotates the tool changing arm between a standby position where it waits until a command is received and a tool gripping position where it grips a tool mounted on the tool spindle or a tool mounted on the tool stocker; a second actuator that moves the tool exchange arm back and forth in the direction of its rotation axis in order to attach and detach the tool after the exchange arm has pivoted to the tool gripping position; and the tool exchange arm is brought to the forward position by the second actuator. a third actuator that rotates the tool exchange arm 180 degrees between the tool spindle of the machine tool and the tool stocker to exchange the position of the gripped tool; a cover that can be opened and closed and is disposed between the tool spindle and the first
opening the cover in synchronization with the actuator pivoting the tool change arm from the standby position to the tool gripping position; and opening the cover in synchronization with the actuator pivoting the tool change arm from the tool gripping position to the standby position. The invention is characterized by comprising a cover opening/closing mechanism connected to the first actuator so as to close the cover.

[Effect]

In the above configuration, the first actuator is actuated to rotate the tool exchange arm between the standby position and the tool gripping position, and the cover is opened in synchronization with the rotation from the standby position to the tool gripping position. In the tool gripping position, the second actuator is actuated to advance the tool changing arm to remove the tool from the tool spindle and carry it on the tool gripper at one end of the arm (while simultaneously removing the tool from the tool preparation means and transferring it to the other end of the arm). The third actuator then pivots the tool changing arm between the tool spindle and the tool stocker, supplying the tool spindle with a new tool (the tool stocker carrying the new tool). supplied with finished tools). The second actuator is then actuated to move the tool changing arm backwards to attach the tool to the tool spindle (and simultaneously transfer the tool to the tool stocker). Finally, the first actuator is actuated to close the cover in synchronization with pivoting the tool exchange arm from the tool gripping position to the standby position.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

Referring to FIGS. 2 and 3, the machine tool includes a bed 10, a column 12, a spindle head 14 attached to the column 12, a spindle 16, and a table 1.
8 and a pallet stocker 20 for replacing pallets. In this embodiment, the main shaft 16 is arranged horizontally, and the main shaft head 14 is mounted so as to be movable in the vertical direction (Y direction) with respect to the column 12 by a known slide guide mechanism. The column 12 is movable in the left-right direction (X direction) on the bed 10 when viewed from the front of the machine tool (in the following description, the direction seen from the arrow in FIG. 3 is taken as the front) by a slide guide mechanism. Similarly, the table 18 is movable on the bed 10 in the front-back direction (Z direction). Therefore, the main shaft 16 is movable relative to the table 18 in three directions: X, Y, and Z.
Further, a tool magazine 22 and a tool changing arm 24 of an automatic tool changer are arranged on the left side of the main shaft 16, and an NC control device 26 is arranged on the right side of the column 12. The tool magazine 22 and the tool exchange arm 24 are attached to a machine frame F (second
(omitted in the figure and FIG. 3).

As shown in FIG. 5, the tool magazine 22 has a disk shape with a plurality of pockets 28 on the outer periphery, and a tool 32 supported by a socket 30 is accommodated in each pocket 28. The tool magazine 22 can be rotated clockwise or counterclockwise as shown by arrow R, and the desired tool 32 to be used next can be rotated clockwise or counterclockwise.
can be indexed to a position A facing the tool exchange arm 24. In some embodiments, tool preparation device 34 includes tool magazine 22 and tool change arm 24.
is established between. The tool preparation device 34 extracts the selected and indexed tool 32 from the tool magazine 22 together with the socket 30 and makes it stand by at a predetermined position B for tool exchange, and also removes the tool 32 after being used by the spindle 16 from the tool exchange arm 24. It is to be received and returned to the tool magazine 22. For this reason, the fourth
As shown, the tool preparation device 34 is mounted on a piston rod 38 of a hydraulic cylinder 36 mounted on the machine frame F and is movable radially and horizontally relative to the tool magazine 22. The tool preparation device 34 is equipped with a gripping means for gripping the tool 32 together with the socket 30.
Detailed explanation will be omitted. The tool stocker described in the claims of the utility model registration refers to the tool magazine 22 and the tool preparation device 34 in this embodiment.
Note that if the tool preparation device 34 is not provided, a configuration may be adopted in which the tools 32 on the tool magazine 22 are directly exchanged.

In FIGS. 2 and 3, a tool 32a that has been extracted from the tool magazine 22 and held in the tool preparation device 34 is shown as being held in the spindle 16 when the tool reaches the uppermost left-hand tool exchange position. The tool being used is indicated by 32b. The tool exchange arm 24 is supported by the machine frame F via a hydraulic cylinder device 40, and the tools 32a and 32b at the center of rotation of the tool exchange arm 24 and the gripping position.
are located on a straight line at the same height, and the distances from the center of the tool exchange arm 24 to the tools 32a and 32b are equal.

Furthermore, a splash guard 42 is provided to surround the machining area in order to prevent chips, cutting fluid, etc. from scattering from inside the machining area including the spindle 16 and the table 18 to the outside. A retractable cover 44 is vertically movably disposed between the tool changing arm 24 and the main shaft 16.
is a part of the splash guard 42.

Next, details of the automatic tool changer and cover 44 will be explained with reference to FIGS. 1, 4, and 5.

Referring to FIG. 4, hydraulic cylinder assembly 40 includes a hydraulic cylinder 46, a piston 48, and a piston rod 50. The piston rod 50 extends long on both sides of the piston 48 and is supported by the machine frame F via bearings 52 and 54 at both ends. In this case, therefore, the piston 48 and the piston rod 50 are longitudinally stationary and the hydraulic cylinder 46 is longitudinally movable. Tool change arm 24 is attached to hydraulic cylinder 46 via bracket 52.

Further, two sliding guide rods 54 are provided parallel to the piston rod 50, and these sliding guide rods 54 and piston rod 50 are fixed by a bracket 56. A bracket 58 similar to bracket 52 is provided, and these brackets 52, 58 include bushings for sliding the sliding guide rod 54. The tool changing arm 24 is thus movable together with the hydraulic cylinder 46 in the axial direction of the piston 48 and the piston rod 50, and together with the sliding guide rod 54 and the piston rod 50.
It is possible to pivot around the zero axis. For driving in the axial direction, a hydraulic passage 60 is formed in the piston rod 50, and a hydraulic pressure supply device 62 is attached to the end of the piston rod 50. Further, a pinion gear 64 for rotational driving is attached to one end of the piston rod 50.

Referring to FIG. 1, this pinion gear 64 is arranged facing the machine frame F on the front side.
A vertical slide guide 66 is provided on the machine frame F, and a rack 68 is attached to this slide guide 66.
It is provided so as to be movable in the vertical direction along. Rack 68 engages pinion gear 64 and its vertical movement causes pinion gear 64 to rotate, thereby causing tool change arm 24 to pivot.

The rack 68 is a two-stage hydraulic cylinder 70, 72.
connected to. The first stage hydraulic cylinder 70 is fixed to the machine frame F by a bracket 74. A bracket 78 is attached to the piston rod 76 of the first stage hydraulic cylinder 70.
The second stage hydraulic cylinder 72 is attached to this bracket 78.
can be attached to. Bracket 82 attached to piston rod 80 of second stage hydraulic cylinder 72
is connected to rack 68. In this case, the first stage hydraulic cylinder 70 is designed to have a stroke that rotates the pinion gear 64 90 degrees, and the second stage hydraulic cylinder 72 is designed to have a stroke that rotates the pinion gear 64 180 degrees. Therefore, the first
When both the second-stage hydraulic cylinders 70 and 72 are lifted, the pinion gear 64 (tool exchange arm 24) rotates 270 degrees.

As shown in FIGS. 1 and 4, the cover 4
Reference numeral 4 designates a vertically arranged plate-like member, whose both end surfaces are guided by guides 84. In the embodiment, the cover 44 is normally closed when in the upper position shown in FIG. 1, and is closed when it is in the lower position. It opens when you move to . The cover 44 is the first
The cover 44 is connected to the hydraulic cylinder 70 of the stage.
The opening and closing of the tool changing arm 24 is performed simultaneously with the turning movement of the tool changing arm 24. In the example,
A rack and pinion mechanism is employed in this connection drive mechanism. However, other mechanisms such as pulley and belt mechanisms may also be employed.

In the embodiment, a rack 86 is attached to one end surface of the cover 44. The rack 86 is engaged with a pinion gear 88, the pinion gear 88 is integrated with a speed increasing pinion gear 90, the pinion gear 90 is engaged with a rack 94, and the pinion gear 88 is integrated with a pinion gear 90 for increasing speed.
4 is connected to a bracket 78 attached to the piston rod 76 of the first stage hydraulic cylinder 70.
This rack 94 is located below the rack 68 and can be moved along the slide guide 68 for the rack 68. pinion gear 88 and 9
The speed increasing ratio of 0 is set so that when the rack 94 moves by the stroke of the cylinder 70, the cover 44 is completely lowered.

Referring to FIG. 5, the tool changing arm 24 is of a double gripper type having tool grippers 96 at both ends, and each tool gripper 96 has an approximately semicircular gripping portion and can be moved forward and backward by a spring. It has a holding part 98. The tool changing arm 24 is designed to maintain the vertical state shown in FIG. 5 during machining, and this state is referred to as the tool changing arm 24 being in the standby position. The cover 44 is located very close to the tool changing arm 24 in the standby position. Further, the tool change arm 24 can be pivoted from the state shown in FIG. This state is said to be that the tool changing arm 24 is in the tool gripping position.

Next, the operation will be explained with reference to FIGS. 6 to 8.

FIG. 6 shows the pivoting position of the tool changing arm 24, and for identification of the pivoting position, the tool changing arm 24 is
One end of 4 is shown in black. FIG. 7 shows the position of a bracket 82 connecting a rack 68 for pivoting the tool changing arm 24 and a piston rod 80 relative to the slide guide 66. There are three operating positions of the bracket 82 (in units of 90 degree rotation of the tool exchange arm 24) depending on the operating positions of the first and second stage hydraulic cylinders 70, 72. FIG. 8 shows the rack 9 corresponding to the opening/closing position of the cover 44.
4 and the piston rod 76 are shown (blacked out).

As shown in FIG. 6a, the tool change arm 24 is in a vertical standby position during machining.
Bracket 82 is in the lower position. Also, cover 44 is in the upper closed position and bracket 78 is in the lower position.

When exchanging tools, first stage hydraulic cylinder 70 is operated. As shown in b of each figure,
The bracket 78 moves to the upper position and the cover 44
is lowered and opened, and at the same time, the bracket 82 is raised to the first operating position C and the tool change arm 24 is opened.
Rotate 90 degrees to bring the tool changing arm 24 to the tool gripping position. These two operations are performed synchronously,
Since the time for opening the cover 44 is absorbed within the time for rotating the tool changing arm 24, no special time is required for opening the cover 44, reducing the overall tool changing time. can be achieved.

Next, when the tool gripper 96 grips the tool 32a gripped by the tool preparation device 34 and the tool 32b gripped by the spindle 16, the hydraulic cylinder 46 is activated. Since the first stage hydraulic cylinder 70 remains in the operating state, the bracket 7
8 is maintained in the upper position, so that the cover 44 continues to be open. When the hydraulic cylinder 46 is actuated, the tool changing arm 24 is moved from right to left in FIG.
Remove.

Next, the second stage hydraulic cylinder 72 is operated while the first stage hydraulic cylinder 70 is maintained in the operating state. As shown at c in each figure, the bracket 78 is in the upper position and continues to open the cover 44, and the bracket 82 is raised to the third operating position E to move the tool change arm 24 clockwise. Rotate a total of 270 degrees (further rotate 180 degrees from the tool gripping position). Therefore, the tool preparation device 3
4 and the tool 32a and tool 32b for the main shaft 16
The positions of are reversed, the tool 32a to be used next comes to the position of the spindle 16, and the used tool 32b comes to the tool preparation device 34.

Therefore, the first and second stage hydraulic cylinders 70,
72 in the operating state, the hydraulic cylinder 46 is operated in the opposite direction, and each tool 3 is
2a and 32b are stored in the main spindle 16 and the tool preparation device 34.

Finally, the first stage hydraulic cylinder 70 is deactivated (conversely activated) while the second stage hydraulic cylinder 72 is maintained in the activated state. Then, as shown in d of each figure, the bracket 82 is lowered by the amount by which the first stage hydraulic cylinder 70 is deactivated and reaches the second operating position D, and the tool change arm 24 is rotated 90 degrees in the opposite direction. Then, the bracket 78 moves to the lower position and the cover 44 is closed.

During machining, the tool preparation device 34 cooperates with the tool magazine 22 to prepare the next tool 32 for use. When the next tool is replaced, the first stage hydraulic cylinder 70 is operated (bracket 82
from the second operating position D to the third operating position E) rotates the tool changing arm 24 by 90 degrees to bring it from the standby position to the tool gripping position, opens the cover 44, and then operates the hydraulic cylinder 46. to remove the tool 32, and then deactivate the second-stage hydraulic cylinder 72 (conversely by activating it (move the bracket 82 to the first operating position C))
The tool exchange arm 24 is rotated 180 degrees counterclockwise to exchange the tool position, then the tool 32 is stored by operating the hydraulic cylinder 46, and finally the first stage hydraulic cylinder 70 is deactivated. Therefore, the bracket 82 is returned to the lower position and the tool changing arm 24 is
is set to the standby position, and at the same time, the bracket 78 is set to the lower position and the cover 44 is closed. In this way, the tool change arm 24 is rotated through 180 degrees in alternate directions of rotation.

[Effect of idea]

As explained above, according to the present invention, the tool changing arm can be rotated and moved back and forth, and the cover disposed between the tool changing arm and the main shaft of the machine tool can be used as the first cover for the tool changing arm. The first actuator opens the cover synchronously when the tool changing arm is rotated from the standby position to the tool gripping position, and synchronously when the tool changing arm is turned from the tool gripping position to the standby position. Since the cover is configured to be opened and closed, the time required to open and close the cover is included in the time it takes for the tool exchange arm to rotate between the standby position and the tool gripping position, and the time required to open and close the cover is included in the time it takes to change the tool. This can be virtually ignored in terms of time, and tool change time can be reduced. In addition, there is no need for a dedicated actuator to open and close the cover, and the first actuator is shared.
The structure is simple, the cover opens and closes reliably in synchronization with the rotation of the tool exchange arm, and is highly reliable, and the cover can be kept open continuously during the continuous rotation of the tool exchange arm.

[Brief explanation of the drawing]

Fig. 1 is a front view of the tool changer seen from the arrow in Fig. 4, Fig. 2 is a front view of a machine tool equipped with the tool changer according to the present invention, seen from the arrow in Fig. 3; FIG. 4 is a plan view of the machine tool shown in FIG. 2, FIG. 4 is a plan sectional view of the tool changing device shown in FIGS. 2 and 3, and FIG. FIG. 6 is a diagram illustrating the turning operation of the tool changing arm, and FIG. 7 is a diagram showing the operation of the bracket that drives the rack connected to the first and second hydraulic cylinders to turn the tool changing arm. Figure 8 is a diagram explaining the first step to open and close the cover.
FIG. 2 is a diagram illustrating the operation of a bracket that drives a rack connected to a hydraulic cylinder. 16... Spindle, 22... Tool magazine, 24...
...Tool exchange arm, 32, 32a, 32b...Tool, 34...Tool preparation device, 40...Arm support hydraulic cylinder device, 44...Cover, 36, 4
6, 70, 72... Hydraulic cylinder, 64... Arm rotation pinion gear, 68, 86, 94... Rack, 88, 90... Cover opening/closing pinion gear.

Claims (1)

[Scope of utility model registration request] In an automatic tool changer in which a tool exchange arm having tool grippers at both ends exchanges tools by rotating between a tool spindle and a tool stocker of a machine tool, the tool exchange arm waits until a tool exchange command is received. a first actuator that pivots the tool changing arm between a standby position and a tool gripping device that grips a tool mounted on the tool spindle or a tool mounted on the tool stocker;
a second actuator that moves the tool exchange arm back and forth in the direction of its rotation axis in order to attach and detach the tool after the tool exchange arm has pivoted to the tool gripping position; The tool change arm is moved 180 degrees between the tool spindle of the machine tool and the tool stocker.
a third actuator that rotates the gripped tool to change the position thereof; a cover that can be opened and closed and is disposed between the tool change arm and the tool spindle of the machine tool in the standby position; and the first actuator. opens the cover in synchronization with rotating the tool change arm from the standby position to the tool gripping position, and opens the cover in synchronization with the rotation of the tool change arm from the tool gripping position to the standby position. an automatic tool changer comprising: a cover opening/closing mechanism connected to the first actuator so as to close the cover.