JPH0242620B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a tool replacement method applied to an automatic machine tool.

[Conventional technology]

Recently, many machining systems (FMS) have been seen in which many machining centers are installed side by side and these machine tools are collectively controlled by a computer. As with any other tool, the tools used in this equipment must be replaced when they reach the end of their service life, break, or when the object of processing changes.

Conventional tool replacement methods include: (a) Stopping the machine tool and manually replacing the tool in the special tool magazine installed in the machine tool.

(b) Make the tool magazine of the machine tool replaceable and replace the tools together with the magazine.

(c) Swap between the dedicated tool magazine installed on the machine tool and another replacement tool magazine (submagazine).

etc. are being adopted.

[Problem to be solved by the invention]

In the case of (a) above, the operating rate is low because it is necessary to stop the machine and replace tools, and it also requires human labor, which has the disadvantage that unmanned operation cannot be achieved. In the case of (b), common tools and dedicated tools are used depending on the process and object of the workpiece in general machining, but when storing them in one tool magazine, the entire magazine must be replaced. The replacement method requires a shared tool for each magazine, which is uneconomical, and it also requires the use of ordinary tools such as the drive device of a large loading device such as a drum changer (magazine changer) that loads magazines into machine tools. This method has disadvantages such as requiring equipment other than the tool changing device, being expensive, and requiring a large space.

Furthermore, in case (c), a dedicated tool indexing device for the replacement tool magazine and its drive device are required, which, like in case (b) above, is expensive and takes up a lot of space. be.

In addition to the above, there has also been a proposal in which a tool pallet is equipped with a tool shelf and a tool changing device (robot), and the tools placed on the tool shelf are replaced by a robot. No. 70579),
When replacing a tool, other tools tend to get in the way, which places significant restrictions on the number of tools and their arrangement. In addition, the equipment becomes expensive due to the need for robot equipment.

The present invention is a tool replacement method that does not require a large loading device or drive device such as a drum changer, and can facilitate tool replacement by simply adding a simple device to an existing machine tool. The purpose is to provide

[Means to solve the problem]

In order to achieve the above object, the present invention provides a machine tool in which tools are exchanged directly or indirectly between a main spindle and a special tool magazine in which the tool is installed with the axial direction of the tool coincident with the main spindle axis. A posture changing device that is removably installed in a replacement tool magazine, etc., and includes a holding mechanism and a posture changing mechanism that is operated by the rotation of the main shaft to change the posture of the tool holding mechanism, A tool that is attached to the spindle by movement and held in a tool holder of a replacement tool magazine placed in front of the spindle of a machine tool when the tool is replaced, with the axial direction pointing in a direction different from the axis of the spindle. is held by the tool holding mechanism of the attitude changing device by relative movement of the attitude changing device with respect to the replacement tool magazine, and removed from the tool holder of the replacement tool magazine, and then the attitude of the tool held in the tool holding mechanism is changed to the above-mentioned position. The rotation of the spindle activates the attitude change mechanism to change the axial direction of the tool so that it becomes parallel to the axis of the spindle, and the tool is held directly or held between the tool holding mechanism of the attitude change device and the dedicated tool magazine. It is configured so that it can be replaced with a new tool.

〔Example〕

FIG. 1 shows the related structure of a machine tool B, which is an object of the present invention, a posture changing device A, etc. The machine tool B has a conventionally well-known tool magazine 1 (hereinafter referred to as a dedicated tool magazine) which is always attached to the machine tool B. (referred to as magazine)
and a tool changer 2, the tool changer 2
, one tool 3 is taken out from the special tool magazine 1, the axial direction of the tool 3 matches the axis of the main spindle 4, and the tool 3 is mounted on the main spindle 4, and the tool 3 is removed from the main spindle 4.
can be removed and returned to the dedicated tool magazine 1. Auto pallet changer D is installed in front of rotary table C of machine tool B above.
A work pallet F or a tool pallet C is transported by an automatic guided vehicle E.
can be fed onto the rotary table C through the automatic pallet changer D. In addition, the above-mentioned machine tool B, rotary table C, or auto pallet changer D
etc. are well known. The attitude changing device A was developed by the present applicant and is detachably attached to a tool pallet G or a replacement tool magazine H loaded on the pallet G.

FIG. 2 shows an example of the attitude changing device A.
5 in the figure is a frame. In this frame 5,
The rotating shaft 6 and the driven shaft 7 mesh with each other's bevel gears 8 and 9, and are pivotally connected to each other at an angle of 45 degrees in a vertical plane so as to be rotatable in the circumferential direction. Stopper 1 provided in 4a)
A locking pin 11 is provided which is locked to 0. This locking pin 11 is biased by a spring 11a in the direction of protruding from the frame 5, and normally the protruding piece 11b fixed to the locking pin 11 is attached to the rotating shaft 5.
The rotary shaft 6 is engaged with an engaging groove 6b of a locking shaft 6a fixed to the rotary shaft 6, thereby fixing the rotary shaft 6 at a predetermined rotational position. The rotary shaft 6 has a tapered shaft portion at its outer end that matches the tapered hole of the main shaft 4, and a shank shaft 12 having a key groove that fits into the key of the main shaft. The shank shaft 12 is inserted into the hole to prevent the frame 5 from rotating together, and is held in the main shaft 4 of the machine tool B and supported horizontally, and rotates together with the main shaft 4 to form the driven shaft 7.
It is designed to rotate.

On the other hand, at the outer end of the driven shaft 7, there is a rotating arm 14 having a tool holding mechanism 13 such as a well-known tool pot or a spring clamp at the tip.
It is rotatably mounted around a driven shaft 7 within a plane inclined at 45 degrees. This rotating arm 14 is rotated by the driven shaft 7 around the driven shaft 7, and changes the tool 3 held by the tool holding mechanism 13 from a vertical state to a horizontal state, and from a horizontal state to a vertical state. By touching a stopper 15 provided on the frame 5, the rotating shaft 6 and the driven shaft 7 are stopped at two positions, upper and lower, in a perpendicular plane including the central axes of the driven shaft 7.

Note that the rotating shaft 6, the driven shaft 7, and the rotating arm 14 constitute the main body of the attitude changing mechanism. The replacement tool magazine H also includes a main pillar _H1 erected on the pallet G, a disk-shaped support plate _H2 horizontally fixed to the upper end of the main pillar _H1 , and this support plate. It consists of a plurality of tool holders 16 provided at appropriate intervals along the outer periphery of _H2 . Each holder 16 grips the flange groove 3a of the tool ₃ through the elasticity of a spring with a pair of grippers rotatably supported on the outer periphery of the support plate H2. ₂ , and between the pair of grippers, there is a groove to prevent the tool gripped by the grippers from rotating.
A key that fits into the keyway of the tool 3 is provided. Since the tool 3 is held vertically in the tool holder 16 of the replacement tool magazine H as described above, the tool 3 can be exchanged between the replacement tool magazine H and the dedicated tool magazine 1 by the tool changer 2. I can't.

Next, the tool changing method of the present invention will be explained step by step, starting from tool removal.

The tools 3 prepared at the tool station are held in each tool holder 16 of a predetermined replacement tool magazine H placed on a predetermined tool pallet G.
The computer that controls machine tools, etc., stores the tool palette number (replacement tool magazine number), the tool number in the replacement tool magazine H, and the tool code (tools are assigned absolute codes). be done. The tool pallet G with the replacement tool magazine H set therein waits at a pallet storage location or the like until a replacement command is received from the computer. The attitude changing device A is removably stacked on the tool pallet G or the replacement tool magazine H.

When a replacement command is issued according to the machining schedule, the tool pallet G with the replacement tool magazine H set is placed on the automatic guided vehicle E and delivered to the automatic pallet changer D located in front of the main spindle 4 of the machine tool B. and then pulled into the automatic pallet chainer D together with the replacement tool magazine H. When machine tool B is machining, tool pallet G waits on automatic pallet changer D until machining is completed.

When machining by machine tool B is completed, tool pallet G is transferred to rotary table C of machine tool B. In addition, in parallel with the above, the tool 3 held in the spindle 4 is transferred to the dedicated tool magazine 1 by the action of the tool changer 2. The main shaft 4 from which the tool 3 has been removed grips the shank shaft 12 and takes out the attitude changing device A from the tool pallet G or replacement tool magazine H on which it is loaded. At this time, the locking pin 11 of the frame 5 is inserted into the hole of the stopper 10, and the frame 5 is fixed to the machine tool B (see FIG. 2). At this time, the locking pin 11 comes into contact with the end surface of the hole and is pushed to the right in FIG.
Since the rotation shaft 6 is disengaged from the engagement groove 6b, the rotation shaft 6 becomes free to rotate.

The main spindle 4 (spindle head 4a) that supported the attitude changing device A in this manner moves forward to the right from the state shown in FIG. 3, move the tool holding mechanism 13 directly below the tool holding mechanism 13, then move it upwards to hold the replacement tool 3 in the tool holding mechanism 13, then retreat to the left in the figure, remove the replacement tool 3 from the tool holder 16, and remove the main spindle 4. The rotating shaft 6 is rotated, and the rotating arm 14 is rotated 180 degrees via the bevel gears 8 and 9 and the driven shaft 7. Due to the above-described rotation of the rotation arm 14, the replacement tool 3, which had been vertically held by the tool holding mechanism 13, becomes horizontal as shown by the two-dot chain line in FIG.

Immediately after the spindle 4 finishes leveling the replacement tool 3, it moves up and down and left and right to bring the replacement tool 3 to the tool exchange (replacement) position. This tool conversion position is
Replacement tool 3 held horizontally by rotating arm 14
This is a position where the axial direction coincides with the axis of the main spindle 4 at a normal tool exchange position where tools are exchanged between the dedicated tool magazine 1 and the main spindle 4. The tool changer 2 takes out the tool to be replaced from the dedicated tool magazine 1 and waits until the main spindle 4 places the replacement tool 3 at the tool exchange position, and then takes out the replacement tool held by the tool holding mechanism 13 of the rotation arm 14. 3 reaches the tool changing position as described above, the rotating arm 14
The replacement tool held in the tool holding mechanism 13 of the rotary arm 14 is grabbed and removed from the tool holding mechanism 13, and the tool taken out from the dedicated tool magazine 1 is held in the tool holding mechanism 13 of the rotating arm 14, and then the tool holding mechanism 13 of the rotating arm 14 is held. The tool taken out from the mechanism 13 is loaded into the dedicated tool magazine 1. In other words, the tool 3 held in the tool holding mechanism 13 of the attitude changing device A
is connected to the dedicated tool magazine 1 via the tool changer 2.
indirectly attached to the

The main shaft 4 is a tool holding mechanism 13 of the rotating arm 14.
When the tool to be replaced is installed by the tool changer 2, it rotates in the opposite direction to the previous direction, rotating the rotating arm 14 from the state shown by the two-dot chain line in FIG. 2 to the state shown by the solid line in the figure. After the replacement tool 3 is made vertical, it is moved from the tool replacement position to the replacement tool magazine H side, and then the flange groove 3a of the tool 3 to be replaced is
The position is the tool holder 16 of the replacement tool magazine H.
After moving forward to the right in Fig. 2, it descends to take out the tool 3 to be replaced from the tool holding mechanism 13, and removes the tool from the empty replacement tool magazine H. Attach it to the tool 16 and retreat.

The above completes one tool replacement, but when many tools are replaced, the above operation is repeated. In this case, the rotary table C rotates with the tool pallet C placed thereon to index the next tool.

The main spindle 4, which has moved back after attaching the tool to be replaced to the tool holder 16 of the replacement tool magazine H, returns the attitude changing device A to the tool pallet G or the replacement tool magazine H, and has the next command.

FIG. 3 shows another example of the attitude changing device A. This attitude changing device has a movable nut 1 having a locking key 17 on a rotating shaft 6 configured as a screw shaft.
The locking key 17 is fitted into a sliding groove 19 provided in the frame 5 to be movable in the axial direction of the rotating shaft 6, and the tool holding mechanism 13
The pivot arm 14 with
A link 23 is attached between the movable nut 18 and the rotating arm 14 with its both ends connected to the movable nut 18 and the rotating arm 14 by connecting shafts 22 and 24. It is being

In this posture changing device, when the main shaft 4 grips the shank shaft 12 and rotates the rotating shaft 6 in one direction, the movable nut 18 moves to the left in FIG. When pushed upward, the movable nut 18 moves to the right in FIG. 3 and stands up vertically using the pivot shaft 20 as a fulcrum as shown by the two-dot chain line in the same figure, and when the rotating shaft 6 is rotated in the other direction. The rotary arm 14, which is currently in use, can be tilted horizontally as shown by the solid line. Note that since the tool holding mechanism 13 of this embodiment is attached to the rotating arm 14 at right angles, it becomes vertical when the rotating arm 14 becomes horizontal, and becomes horizontal when the rotating arm 14 becomes vertical.

Reference numeral 25 in FIG. 3 is a stopper attached to the frame 5, 26 is a stopper attached to the locking pin 11, and the former stopper 25 horizontally stops the rotating arm 14 to hold the tool. The mechanism 13 is properly vertical, and the latter stop 26 is adapted to stop the pivot arm 14 vertically to properly level the tool holding mechanism 13. Stopper 25, 2
6, a bolt is usually used to allow fine adjustment. The rotating shaft 6, the link 23, and the rotating arm 14 constitute the main body of the attitude changing mechanism. The attitude changing device of this example has the main shaft 4,
The tool holding mechanism 13 is lowered from top to bottom, and the replacement tool held in the tool holder 16 of the replacement tool magazine H with the taper shank facing upward is held in the tool holding mechanism 13, and the tool to be replaced is held in the tool holding mechanism 13. The tool holder 16 of the replacement tool magazine H holds the taper shank with the taper shank facing upward, and then rises to remove the tool to be replaced from the tool holding mechanism 13. A description of the tool replacement method using this attitude changing device will be omitted.

In this example, it goes without saying that the tool holding mechanism 13 has a built-in appropriate locking mechanism (not shown) to prevent the held tool from falling due to its own weight.

The above description has been made of the case where the tool changer 2 is used to indirectly perform normal tool exchange between the dedicated tool magazine 1 and the spindle 4 in a machine tool equipped with an automatic tool change device. The present invention is not limited to this, and can also be applied to a machine tool in which tools are directly exchanged between the dedicated tool magazine 1 and the spindle 4 without using the tool changer 2.

That is, FIG. 4 shows a machine tool without a tool changer, in which a special tool magazine 1 is arranged above the main shaft 4 so as to be rotatable in a vertical plane, and the special tool magazine 1 is installed in the special tool magazine 1. After the main shaft 4 rises backward from the lowest tool 3 among the plurality of tools (only one is shown in the figure),
It moves forward a little to grip the tool 3, and then descends downward to extract the gripped tool from the dedicated tool magazine 1. In this case, the replacement tool and the replaced tool are directly replaced between the dedicated tool magazine and the tool holding mechanism 13 of the attitude changing device A.

〔Effect of the invention〕

As explained above, the present invention provides a tool holding mechanism and a tool holding mechanism for a machine tool in which a tool is directly or indirectly exchanged between a main spindle and a special tool magazine in which a tool is mounted with the axial direction of the tool aligned with the main spindle axis. An attitude changing mechanism that is actuated by the rotation of the spindle to change the attitude of the tool holding mechanism, and is detachably installed in a replacement tool magazine, etc. The tool is attached to the main spindle, and when the tool is replaced, the tool held in the tool holder of the replacement tool magazine placed in front of the main spindle of the machine tool with the axial direction facing in a direction different from the axis of the main spindle is replaced. After being held by the tool holding mechanism of the attitude changing device by relative movement of the attitude changing device with respect to the tool magazine and removed from the tool holder of the replacement tool magazine,
The attitude of the tool held in the tool holding mechanism is changed by activating the attitude changing mechanism by rotation of the spindle so that the axial direction of the tool is parallel to the axis of the spindle, and the tool holding mechanism of the attitude changing device is It is structured so that tools can be exchanged directly or indirectly with a dedicated tool magazine, and there is no need for a large loading device such as a drum changer, its drive device, or a multi-functional robot, and it is easy to use. It has the advantage that it can be implemented on existing machine tools simply by using a posture changing device with a similar structure.

[Brief explanation of drawings]

Fig. 1 is a schematic plan view showing an overview of a machine tool and an attitude changing device, etc., which are objects of the present invention, Fig. 2 is a front view showing an example of an attitude changing device used in carrying out the present invention, and Fig. 3 is Front view of other attitude changing device,
FIG. 4 is a front view of a machine tool without a tool changer. A...Position conversion device, B...Machine tool, H...Replacement tool magazine, 1...Special tool magazine, 3...Tool, 4...Main shaft, 6...Rotating axis, 7...Driver axis, 13...
Tool holding mechanism, 14... Rotating arm, 16... Tool holder.

Claims (1)

[Claims] 1 In a machine tool B in which the tool 3 is directly or indirectly replaced between the main spindle 4 on which the tool 3 is mounted with the axial direction of the tool 3 aligned with the main spindle axis line and the dedicated tool magazine 1, the tool holding mechanism 13 and the above-mentioned main spindle 4
An attitude changing device A is provided with attitude changing mechanisms 6, 7, and 14 that are actuated by the rotation of the tool holding mechanism 13 to change the attitude of the tool holding mechanism 13, and is detachably installed in a replacement tool magazine H or the like. When the tool 3 is replaced, the axis of the main spindle 4 and the tool holder 16 of the replacement tool magazine H placed in front of the main spindle 4 of the machine tool B are attached to the main spindle 4 by moving the main spindle 4 relative to the tool 3. The tool 3 held with its axial direction in a different direction is held by the tool holding mechanism 13 of the attitude changing device A by the relative movement of the attitude changing device A with respect to the replaceable tool magazine H, and the tool is held in the replaceable tool magazine H. After being removed from the tool 16, the attitude of the tool 3 held in the tool holding mechanism 13 is changed to the attitude changing mechanism 6, 7, 14 by rotation of the main shaft 4.
is operated so that the axial direction of the tool 3 is parallel to the axis of the spindle 4, and the tool 3 is directly or indirectly transferred between the tool holding mechanism 13 of the attitude changing device A and the dedicated tool magazine 1. A tool replacement method characterized by replacing the tool.