JPS6157138B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tool attachment/detachment device for an attachment.

The conventional automatic tool change method for attachments is
A pressing device for opening the tool gripping collet in the attachment spindle is installed at the tool exchange origin position,
When changing a tool, the attachment body is moved to the tool change origin position, the pressing device and the attachment are connected, the pressing device is operated to open the collet, and the tool is attached or removed. In addition, if the tool does not have an automatic exchange system, the shaft for attaching and removing the tool is a screw type, and the tip of the collet is opened by manually screwing the shaft.

As described above, the automatic exchange system requires a separate device for attaching and removing tools externally, and automatic exchange is possible only at the tool exchange origin position. Furthermore, it is difficult to attach and detach tools of special shapes that cannot be stored in the tool magazine of the automatic tool changer. In addition, in the case of a manual method, two or more people usually need to work, which takes a lot of time.

The present invention eliminates the above-mentioned problems, and provides an attachment that not only automatically attaches and detaches tools using an automatic tool changer, but also allows special tools to be attached and detached at any position on the attachment in a short time. The present invention aims to provide an automatic tool changer.

Hereinafter, one embodiment of the present invention will be described based on the drawings. First, the outline of the machine tool of the present invention will be explained based on FIGS. 1 to 3. This machine tool consists of a quill 2 mounted on the lower surface of the spindle head 1 so as to be able to rise and fall within the spindle head. A cylindrical attachment clamp cylinder 3 is installed in the section, and the main body 5 of the attachment 4 is firmly clamped by the clamp cylinder 3. That is, the cylindrical cylinder body 3A of the attachment clamp cylinder 3 is installed on the outer periphery of the quill 2 on the lower surface of the spindle head 1, and the cylindrical piston 3B is mounted on the outer periphery of the cylinder body 3A so as to be movable up and down. Clamp plates 3C are fixed at four locations on the lower end surface of the outer periphery of the piston 3B. Further, a ring-shaped indexing plate 3D is installed on the lower surface of the cylinder body 3A with indexing teeth facing downward.

On the other hand, on the upper outer peripheral surface of the attachment body 5,
The same number of clamp parts 3E as the clamp plates 3C are formed to contact the clamp plate 3C, and a ring-shaped indexer is provided near the clamp parts inside the attachment body 5 to be paired with the lower index plate 3D of the cylinder body 3A. The board 3F is installed with the indexing tooth facing upward. Further, as shown in FIG. 3, an adapter 6 installed at the center of the attachment 4 is fitted into a tapered hole 8 of a main shaft 7 rotatably mounted within the quill 2.
The tip gripping part 9 is the collet 1 installed inside the main shaft 7.
It is held in tension by 0. Further, a drive key 11 installed at the end of the main shaft is inserted into a keyway 13 formed in a flange 12 of the adapter 6.
An internal gear 14 is provided on the bottom surface of the flange 12 of the adapter 6.
is fixedly installed, and the teeth of the internal gear 14 mesh with an external gear 17 fixed to the upper part of a transmission shaft 16 coaxially with the axis A of the main shaft 7 and rotatably supported by a bearing sleeve 15. . An attachment main shaft 19 is rotatably supported on a bearing 18 in a direction perpendicular to the main shaft axis A at the lower part of the attachment main body 5, and a second bevel gear 20 is installed on the outer periphery of the attachment main shaft 19. First bevel gear 21 fitted and fixed to the lower end of shaft 16
are interlocked. In this state, the main shaft 7
The rotation is transmitted to the drive key 11, the adapter 6, the internal gear 14, the external gear 1, the transmission shaft 16, the first bevel gear 21, and the second bevel gear 20, and the attachment main shaft 19 is rotated.

The attachment main shaft 19 is formed into a cylindrical shape, and a collet 23 for gripping the tool 22 is attached to the center of the shaft.
A draw bar 24 for supporting the collet 23 is installed so as to be movable in the axial direction.

As shown in FIG. 4, the collet 23 has elasticity in the vertical opening direction, and its tip grip portion 23
a is configured to abut the small diameter part 25a at the front of the central hole 25 of the attachment main shaft 19 in the closed position a, and expand by its own elasticity to the middle diameter part 25b on the front side of the small diameter part 25a in the open position b. has been done.

The tool attachment/detachment device B according to the present invention utilizes a disc-shaped spring 26 that fits and holds the drawbar 24 and the collet 23, and the lowering of the main shaft 7 in order to bias the collet 23 toward the closed position. A switching means 27 is provided which operates to switch the collet 23 from the closed position a to the open position b against a spring 26.

That is, the switching means 27 includes a second cylinder housing a first piston 28 that moves up and down with the internal gear 14, and a second piston 29 that is disposed coaxially with the rear end of the drawbar 24. 30 and
a hydraulic circuit 31 for moving the second piston 29 in the axial direction by raising and lowering the first piston 28;
It consists of

Also, inside the cylinder 30, a second piston 29
A coil spring 32 is inserted into the outer periphery of the shaft portion of the draw bar 24 to constantly press the second piston 29 to the opposite side of the draw bar 24 (toward the left in the figure). Further, the first piston 28 is mounted between the outer circumference of the internal gear 14 with the flange 14a fixed to the lower surface of the adapter 6 and the inner circumference of the attachment body 5. A plate 33 is installed on the upper surface of the first piston 28 so as to sandwich the outer periphery of the flange 14a of the internal gear 14.
A slide bearing 34 is interposed between the upper surface of the flange 14a of the internal gear 14 and the rotation of the internal gear 14 when the main shaft is driven.
Therefore, the first piston 28 is suspended from the flange 14a of the internal gear 14.
A transmission shaft 16 is located below the first piston 28.
The bearing sleeve 15 bearing the first piston 28 is installed, and the upper cylindrical part of the bearing sleeve 15 is inserted into the inner diameter part of the first piston 28.
The flange portion 15a of the attachment body 5
The pin hole 3 of the lower surface of the first piston 28 is fixed to the mounting seat 35 of the first piston 28 on the upper surface of the flange portion 15a.
A guide pin 36 that fits into the guide pin 7 is fixed.

and the first piston 28 and the bearing sleeve 15
A space formed by the outer circumferential surface of the first cylinder 39, the upper surface of the flange 15a, and the inner circumferential surface of the attachment body serves as a cylinder chamber 40 of the first cylinder 39. A fluid inlet/outlet hole 41 is bored in the attachment body 5 so as to communicate with the cylinder chamber 40, and the fluid inlet/outlet hole 41 is connected to a conduit in a manifold 42 installed near the second cylinder 30 at the rear of the attachment. 43 to the left chamber 30a of the second cylinder 30 on the cylinder cover 43 side. Furthermore, an L-shaped hole 44 is formed in the first piston 28 so as to communicate with the first cylinder chamber 40 and a horizontal hole 45 formed in the attachment body 5, and the horizontal hole 45 is connected to a pipe in the manifold 42. It is connected via a channel 46 to a replenishment tank 47 above it. Further, the right chamber 30b of the second cylinder 30 is communicated with a replenishment tank 47 via a pipe 48 in a manifold 42, and a relief valve 50 is connected to a pipe 49 connecting the pipe 48 and the pipe 43. Intervention is provided.
And the flange portion 15a of the bearing sleeve 15
A valve holding hole 51 is formed in the upper surface, and an auxiliary valve 52 is fitted into the holding hole 39, and a spring 53 is interposed between the bottom of the valve and the bottom of the holding hole 51, so that it can freely move up and down. has been done. and the auxiliary valve 5
A seal 54 is fitted onto the outer periphery of the upper narrow diameter portion 52a of the cylinder 2, and an L-shaped hole 55 is formed inside the cylinder chamber 40 and the L-shaped hole 44 to communicate with each other.

Therefore, the hydraulic circuit 31 is connected to the replenishment tank 4.
7, conduits 43, 46, 48, 49 connecting the first cylinder 39 and second cylinder 30, a relief valve 50, an auxiliary valve 52, etc. Note that 56 is a supply valve for supplying fluid to the second cylinder 30, 57 is a bolt that fixes the tank 47 and the manifold 42, and 58 is a tank level gauge.

Next, the effect will be explained. First, attachment 4
The mounting on the spindle head 1 will be explained. The upper clamp part 3E of the attachment main body 5 is inserted into the piston 3B of the attachment clamp cylinder 3 from between the four clamp plates 3C using an attachment conveyance device (not shown), and then the attachment 4 is moved at a predetermined angle (approximately 45 degrees). ), the clamp portion 3E of the attachment 3 and the clamp plate 3C of the piston 3B intersect by rotating around the vertical axis. Then, when the piston 3B rises due to the operation of the clamp cylinder 3, the clamp plate 3C and the clamp 3E of the attachment 4 come into contact with each other, and when the piston 3B further rises, the attachment body 5 also rises, and the clamp cylinder 3
The teeth of the indexing plate 3D of the cylinder body 3A and the teeth of the indexing plate 3F on the attachment side engage and connect, and the attachment 4 is moved upward by the rising of the piston 3B.
is firmly clamped to the spindle head 1. At the same time, the adapter 6 of the attachment 4 also fits into the tapered hole 8 of the main shaft 7, the gripping part 9 at the top end of the adapter 6 is gripped by the collet 10 in the main shaft 7, and the drive key 11 of the main shaft 7 is inserted into the taper hole 8 of the main shaft 7. Keyway 13
The adapter 6 and the main shaft 7 are connected to each other.

As a result, the attachment body 5 is attached to the spindle head 1.
In addition, due to the connection between the main shaft 7 and the adapter 6, the rotational drive of the main shaft 7 is controlled by the adapter 6, the internal gear 14, the external gear 17, the transmission shaft 16, the first bevel gear 21, and the second bevel gear. Bevel gear 2
0 to the attachment main shaft 19,
The attachment main shaft 19 is rotated.

FIG. 3 shows a tool 22 mounted on the attachment main shaft 19. To explain the working state when replacing the tool 22 from this state, first, the quill 2 in the spindle head 1 is lowered by a certain distance. Then, as the quill 2 descends, the main shaft 7 descends, and the adapter 6 and internal gear 14 are pushed down.
The first piston 28 is also pushed down. Therefore,
The pressure in the cylinder chamber 40 on the lower surface of the first piston 28 increases and the fluid passes through the manifold 42 to the left chamber 30 on the cylinder cover 43 side of the second cylinder 30.
sent to a. The fluid pressure moves the second piston 29 to the right against the coil spring 32 in the second cylinder 30. Due to this movement of the second piston 29, the right shaft end of the second piston 29 comes into contact with the rear end surface of the draw bar 24, and the increased fluid pressure exceeds the force of the disc spring 26 on the outer periphery of the draw bar 24. , push the drawbar 24 to the right. This movement of the drawbar 24 causes the tip of the collet 23 to loosen its grip on the opening tool 22. Then, the tool 22 is pulled out by an automatic tool changer or manually and removed from the attachment main shaft 19.

Next, when attaching a tool, use the automatic tool changer or manually to attach the tool to the attachment spindle 1.
9. When the quill 2 is raised at the time of insertion, the first piston 28 is also forcibly pulled up, thereby reducing the pressure in the cylinder chamber 40. Therefore, the second piston 29 in the second cylinder 30 moves the second piston 29 to the left by the spring 32. With this movement of the second piston, the drawbar 24 moves to the left by the force of the disc spring of the drawbar 24, and the tip of the collet 23 grips the grip portion of the tool 22 and firmly fixes the tool.

Next, the hydraulic circuit will be explained. When the first piston 28 descends a small amount, the auxiliary valve 52 contracts and the L-shaped hole 44 of the first piston 28 is removed from the side hole 45 of the attachment body 5, the tip of the hole 44 is closed, and the replenishment tank 47 is closed. The circuit with the inside of the first cylinder chamber 40 is closed. When the first piston 28 continues to descend further, the pressure in the first cylinder chamber 40 increases, and the working fluid flows through the inlet 41 of the attachment body 5 and the pipe 43 of the manifold 42.
It flows into the left chamber of the second cylinder 30 on the cylinder cover side through the cylinder cover, and operates the second piston 29. When the working fluid pressure further increases due to the lowering of the first piston, the second piston 29 moves further to the right, comes into contact with the rear end surface of the drawbar 24, and pushes the drawbar 24 to the right. Therefore, the tip of the collet 23 opens and the tool 22 can be attached and detached. When the pressure increases due to the lowering of the first piston 28 and exceeds the set pressure, the relief valve 50 is activated as a safety function, the circuit is opened, and a portion of the working fluid returns to the replenishment tank 47. At this time, the working fluid in the right cylinder chamber 30b of the second piston 29 is pushed out and enters the replenishment tank 47.

Next, when installing and fixing a tool, the first piston 28 is raised. Then, the pressure in the first cylinder chamber 40 decreases and the pressure in the second cylinder 30 decreases.
The operating pressure in the left cylinder chamber 30a also decreases. Due to this decrease in operating pressure, the coil spring 3 is lower than the operating pressure.
The biasing force 2 rotates upward and pushes the second piston 29 back to the left. Therefore, the working fluid in the left cylinder chamber 30a of the second piston 29 is
, and returns to the cylinder chamber 40 of the first cylinder 39 . On the other hand, the cylinder chamber 30b on the right side of the second piston 29 is replenished with working fluid from the replenishment tank 47. The horizontal hole 45 and the small hole 44 communicate with each other at the highest position of the first piston 28, and the fluid decreased by the operation of the relief valve 50 is supplied to the replenishment tank 47.
From there, the first cylinder chamber 40 is replenished through the horizontal hole 45 and the fine hole 44.

In addition, in the present invention, the opening operation of the collet can be performed using the ascending motion of the main shaft instead of using the descending motion of the main shaft as in the above embodiment.

As is clear from the above description, in the present invention, an attachment is removably attached to the lower surface of the spindle head that supports the spindle in a vertically movable and rotatable manner, and a tool gripping collet is attached to the main body of the attachment in the closed and open positions. In a machine tool that is internally movable and capable of switching between postures, there is a spring for biasing the collet in the direction of the closed posture, and a spring for biasing the collet in the direction of the closed posture, and a movement of the collet against the spring to move the collet to the closed posture in conjunction with the rise or fall of the main shaft. The present invention relates to a tool attachment/detachment device for an attachment, characterized in that it includes a switching means for switching the tool from the open position to the open position.

Therefore, according to the present invention, there is an excellent effect that the switching means allows tools to be replaced at any position without using an automatic tool changer at the tool change origin position.

[Brief explanation of the drawing]

1 to 6 show an embodiment of the present invention, in which FIG. 1 is a side view showing the attachment attached, FIG. 2 is a rear view, FIG. 3 is a vertical side view, and FIG. is a sectional view showing the open/closed state of the collet,
FIG. 5 is a block diagram of the main parts, and FIGS. 6a, b, and c are sectional views showing the operating state of the auxiliary valve. 1: Spindle head, 2: Quill, 5: Attachment body, 7: Main shaft, 14: Internal gear, 16: Transmission shaft,
19: Attachment main shaft, 23: Collection, 2
4: drawbar, 27: switching means, 25: first piston, 29: second piston, 30: cylinder,
31: Hydraulic circuit.

Claims (1)

[Claims] 1. A workpiece in which an attachment is removably attached to the lower surface of the spindle head that supports the spindle so that it can be raised and lowered and rotatably supported, and a tool gripping collet is installed inside the body of the attachment so that it can be switched between a closed position and an open position. The machine includes a spring for biasing the collet in the direction of the closed position, and a switching means for switching the collet from the closed position to the open position against the spring in conjunction with the rise or fall of the main shaft. A tool attachment/detachment device for an attachment.