JPH0243639Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a tool holder used when connecting a tool to a drive shaft of a machine tool.

[Conventional technology and its problems] A machining center is equipped with a tool magazine that can store a large number of tools and an automatic tool changer. They are attached to the main shaft of the machine in order to perform a series of machining operations continuously.

The tool exchange operation involves indexing the necessary tool inside the tool magazine and moving it to the exchange position of the automatic tool changer.The changer holding the tool moves to a position near the spindle and is attached to the spindle. Exchange it for a tool. Thereafter, the exchange device conveys the exchanged tool to the tool magazine and the exchange operation is completed, but the machine is kept at rest between the conveyance of the tool and the exchange to the spindle.

For this reason, as the number of tool changes increases, the down time of the machine increases. The machining time may be significantly longer than machining using a dedicated machine.

Furthermore, if the shape of the workpiece is complex and the number of processing steps required to complete the product is extremely large, the number of tools stored in the tool magazine may not be sufficient. In this case, there is a problem that tooling for machining becomes insufficient due to the restriction on the number of stored pieces, leading to inefficient machining and automatic operation becoming impossible.

In order to deal with the above-mentioned problems, a rotating device to which a plurality of tools can be attached and which sequentially index the tools to machining positions has been proposed in Japanese Utility Model Publication No. 38-2100.

This device pushes a rack shaft protruding from a fixed member downward, operates a conical clutch by operating an operating rod connected to the rack shaft, and rotates an indexing board and a rotary bearing on which a tool is attached to a machining position. The necessary tools among multiple installed tools can be automatically moved to the working position.
This has the advantage of shortening tool exchange time and increasing the number of stored tools.

However, in the above-mentioned rotating device, it is necessary to push down the rack shaft each time it is operated, so in order to perform an indexing operation while the main shaft is rotating, it is necessary to move the main shaft and press the rack shaft against the main shaft head, or to push the rack shaft down on the machine side. It is necessary to take measures such as installing a push-down device for the easy shaft.

However, in a normal machining center, either the spindle head or the table is movable.
Since the main shaft itself is structured so that it cannot be moved, there is a problem in that it is not possible to move the main shaft and automatically push down the easy shaft.

On the other hand, providing a push-down device for the easy shaft on the main shaft of a machine requires large costs, and there is almost no space for mounting it on the main shaft of a machining center, so it is often difficult to install it in practice. Therefore, there is a problem in that the above-mentioned rotating device cannot be applied to work in which a tool is automatically indexed by being attached to a machining center.

In addition, in the above-mentioned rotating device, the indexing disk and the operating rod contact each other and rotate, and the conical clutch slips while the indexing disk is indexed, which causes wear on the contact parts of the indexing disk and the conical clutch. This tends to occur easily, resulting in unstable operation and the need for frequent replacement of worn parts.

[Purpose of invention]

This invention solves the above-mentioned problems and provides a tool holder that can be attached to a machining center etc. to automatically index tools, as well as reduce wear due to mechanical contact and ensure stable operation. With the goal.

[Means for solving problems]

In order to solve the above problems, this invention rotatably supports a case body on a shank that is removably connected to the drive shaft of a machine tool, and the case body has a shank that is tilted with respect to the axis of the shank. A turret body that rotates around an axis is attached, and a rotation transmission shaft is rotatably attached to the turret shaft installed on the rotation center line of the turret body, and the rotation transmission shaft is connected to the rotation center via a torque transmission mechanism. A plurality of tool rotation axes arranged around the line are connected, the case body is provided with a cylinder that drives the indexing axis so as to be movable along the rotation center line, and the turret body is provided with cylinders that move the indexing axis along the rotation center line. An engagement hole is provided in which the indexing shaft engages, and a gear that constantly transmits the rotation of the shank to the gear shaft is connected to the gear shaft connected to the indexing shaft, and the rotation is transmitted at a position where the indexing shaft is engaged with the engagement hole. A gear connected to the shaft,
At the position where the indexing shaft and the engagement hole are disengaged, attach the gear that connects to the turret shaft, and connect the shank to the drive shaft in the case body, which communicates with the pressurized fluid discharge port provided on the machine tool. A fluid introduction hole is provided, and the fluid introduction hole and the cylinder are communicated with each other.

[Effect]

In the above configuration, when the shank is connected to the drive shaft of the machine tool, the cylinder of the case body communicates with the pressurized fluid discharge port of the machine via the fluid introduction hole.

Now, when pressure fluid is introduced into the cylinder and the shank is rotated with the indexing shaft removed from the engagement hole, the turret shaft rotates via the gear shaft, and the turret body rotates. When the tool rotation axis of the required tool rotates to the machining position, the shank stops rotating and
Drain the pressure fluid from the cylinder. As a result, the indexing shaft engages with the engagement hole, and the tool rotation shaft is indexed.

On the other hand, when the pressure fluid is discharged from the cylinder and the shank is rotated with the indexing shaft engaged with the engagement hole, the rotation of the drive shaft is transmitted from the gear of the gear shaft to each tool via the transmission shaft and torque transmission mechanism. transmitted to the rotating shaft.

Note that, contrary to the above, the indexing shaft and the engagement hole may be engaged by introducing pressure fluid into the cylinder.

〔Example〕

FIG. 1 shows a state in which the tool holder of the embodiment is attached to the main shaft of a machining center.

As shown in the figure, the shank 1 has a tapered portion 1a.
is fitted and positioned inside the main shaft 2, and the pull bolt 3 at the rear end is pulled inward and fixed to the main shaft 2 by a draw bolt mechanism (not shown). As shown in FIGS. 1 and 4, this shank 1 is formed with a flange portion 4 and a V-shaped groove 5, and key grooves 4a provided on both sides of the flange portion 4 are provided on the end surface of the main shaft 2. The key 2a is inserted into the V-shaped groove 5 to transmit the rotation of the main shaft 2, and a grip of a tool changer is fitted into the V-shaped groove 5 to pull out the shank 1 from the main shaft 2.

A case body 7 is rotatably supported at the tip of the shank 1 via a bearing 6. The case body 7 has a circular opening 8, into which the turret body 10 fits and is rotatably mounted by a bearing 9.
The turret body 10 is rotatable about an axis inclined at a predetermined angle with respect to the axis of the shank 1.

One end of a turret shaft 11 is fixed to the center of rotation of the turret body 10, and the turret shaft 1
The other end of the case body 7 is rotatably supported by a support plate 12 of the case body 7. A cylindrical rotation transmission shaft 13 is fitted onto the outside of the turret shaft 11 and is rotatably supported.

Further, the turret body 10 is formed with a plurality of insertion holes 14 for inserting a plurality of tool rotation axes around the rotation center.
The axis of each insertion hole 14 is inclined at a predetermined angle with respect to the center of rotation of the turret body 10, and a tool rotation shaft 15 is inserted into each insertion hole 14 and rotatably supported.

The tip of the tool rotating shaft 15 projects outside the turret body 10, and a tool holder 16 such as a collection chuck or tap holder is attached to the tip.

A sleeve 17 is rotatably supported by a support plate 12 provided on the case body 7, and a gear 18 provided on the sleeve 17 meshes with a gear 19 provided at the tip of the shank 1, causing the shank 1 to rotate. Then, the sleeve 17 also rotates.

A gear shaft 20 is inserted inside this sleeve 17, and a key 22 fits into an axial key groove 21 provided on the outer periphery of the gear shaft 20, within a range where the key 22 abuts both ends of the key groove 21. The gear shaft 20 is movable in the axial direction. Further, due to the engagement between the key 22 and the keyway 21, the rotation of the sleeve 17 is transmitted to the gear shaft 20.

The gear 23 provided on the gear shaft 20 is the gear shaft 2
The turret shaft 11 engages either the gear 24 provided at the rear end of the turret shaft 11 or the gear 25 provided at the rear end of the transmission shaft 13 by the axial movement of the turret shaft 11 .

In this case, the gear 23 of the gear shaft 20 is connected to the transmission shaft 13.
When the gear shaft 20 is engaged with the gear 25, the rotation of the gear shaft 20 is transmitted to the transmission shaft 13, and the rotation of the transmission shaft 13 is as follows.
The torque is transmitted to each of the tool rotation shafts 15 via the torque transmission mechanism 26. The torque transmission mechanism 26 is
A bevel gear 27 is provided on the transmission shaft 13, and the bevel gear 27 is engaged with a bevel gear 28 of the tool rotation shaft 15.

Further, when the gear 23 of the gear shaft 20 is engaged with the gear 24 of the rotating shaft 11, the rotation of the gear shaft 20 is transmitted to the turret shaft 11, and the turret main body 10 rotates.

This turret main body 10 is prevented from rotating by the operation of the indexing mechanism 29, and the turret main body 10
Among the plurality of tool rotation shafts 15 supported by the shank 1 , one tool rotation shaft 15 is held parallel to or perpendicular to the axis of the shank 1 .

The indexing mechanism 29 has a cylinder 30 attached to the support plate 12 of the case body 7, and the cylinder 30
A piston 3 formed on the indexing shaft 31 is inside the piston 3.
1a and a spring 32 that pushes back the piston 31a, and the tip of the lower rod 33 of the indexing shaft 31 is removably inserted into the engagement hole 34 provided in the turret body 10. When the turret body 10 is
It is stopped from rotating. Note that this engagement hole 34 is
The same number of tool rotating shafts 15 are provided.

Also, the upper rod 35 of the indexing shaft 31
and the gear shaft 20 are connected via a connecting plate 36, and when the lower rod 33 is disengaged from the engagement hole 34, the gear 23 of the gear shaft 20 meshes with the gear 24 of the turret shaft 11.

The piston 31a is moved in the axial direction by forcing pressure fluid into the lower part of the cylinder 30. The cylinder 3 below this piston 31a
0 is provided with an inlet 37 for high pressure air, which is pressurized fluid, and the inlet 37 is connected to the fluid introduction hole 3 provided in the part of the case body 7 facing the main shaft head H.
It is connected to 8.

A plug 40 having a through hole 39 inside is attached to the fluid introduction hole 38 so as to be movable in the axial direction. Further, the plug 40 is always urged in the withdrawal direction by a spring 41 housed inside the fluid introduction hole 38, and when the tool holder is attached to the main shaft 2 as shown in FIG. Groove 4 of block 42 provided at the end of head H
Insert into 2a.

This groove 42a has an air discharge port 44 that is guided from an air pump (not shown) through piping inside the machine.
is provided, and the tip of the plug 40 is pressed into contact with this air discharge port 44.

Note that when the tool holder is held in the automatic tool changer and pulled out from the main shaft 2, the plug 40 is biased by the spring 41 as shown in FIG.
One end of the case body 7 is fitted into a groove 43 provided in the flange portion of the shank 1 to prevent the case body 7 from rotating relative to the shank 1. Therefore, the case body 7 is prevented from moving undesirably during tool holder replacement or transportation to the tool magazine, allowing safe tool replacement.

Next, a method for indexing the tool rotating shaft 15 will be explained.

With the main shaft 2 stopped at a predetermined position, high pressure air is passed through the air discharge hole 44 of the block 42 and the fluid introduction hole 38 to the cylinder 3 below the piston 31a.
0, the indexing shaft 31 and gear shaft 20 move in the direction of the arrow, as shown in FIG. In this case, the gear 23 of the gear shaft 20 disengages from the gear 25 of the transmission shaft 13, and the gear 23 of the gear shaft 20 disengages from the turret shaft 11.
At the same time, the tip of the lower rod 33 of the piston 31a is disengaged from the engagement hole 34 of the turret body 10, and the turret body 10 becomes rotatable.

When the main shaft 2 is rotated in this state, the rotation of the main shaft 2 is transmitted to the turret shaft 11 via the gear shaft 20, and the turret main body 10 fixed to the turret shaft 11 is rotated around the turret shaft 11. . At this time, since no rotation is transmitted to the transmission shaft 13, the tool rotation shaft 15 does not rotate.

The tool can be indexed by rotating the main shaft 2 by a predetermined number of rotations derived from the gear ratio between the shank 1 and the transmission shaft 13. That is, by rotating the main shaft 2 a predetermined number of times, the required tool rotation axis 15 can be indexed to a processing position parallel to or perpendicular to the axis of the shank 1.

Next, when the air supply is stopped and the pressure inside the cylinder 30 is reduced, the piston 31a is pushed back by the elastic force of the spring 32, and the tip of the lower rod 33 of the indexing shaft 31 engages the newly indexed turret body 10. The turret main body 10 is fixed by fitting into the matching hole 34. At the same time, the gear shaft 20 is pushed down, the gear 23 engages with the gear 25 of the transmission shaft 13, and the rotation of the shank 1 is transmitted to each tool rotation shaft 15.

In the tool holder configured as described above, a drill for the prepared hole, a chamfering tool for the entrance of the prepared hole, and a tap are attached to each tool rotating shaft 15 in connection with, for example, tap machining, and the tools are attached in accordance with the order of machining. You can perform a series of tap operations in succession by determining the

In addition, in the case of the embodiment, the turret body 10 has two
Although the book tool rotating shaft 15 is shown, the number of rotating shafts is arbitrary, and the number can be four or three as shown in FIG. 5.

Furthermore, although the tool rotation axis that stops at a position parallel to the shank 1 is used as the machining axis, one of the tool rotation axes may be stopped at a position perpendicular to the shank 1 and that axis can be used as the machining axis.

Furthermore, the above tool holder is not limited to machining centers, but can be widely applied to machine tools that rotate tools, such as milling machines and drilling machines.

〔effect〕

As described above, according to this invention, a cylinder for driving the indexing shaft is provided in the case body, and the indexing shaft is engaged with or disengaged from the engagement hole by pressure fluid introduced into and discharged from the cylinder from the machine tool, thereby operating the turret. Since the main body is indexable, the tool can be automatically indexed even when installed in a machine tool that does not have a rack shaft push-down device or a main shaft movement function.

In this case, the machine tool only needs to be provided with a pressure fluid supply port, so it can be easily applied even if there is no space around the main shaft.

In addition, since the index shaft is moved to engage or disengage from the engagement hole by the operation of the cylinder, wear due to mechanical contact rotation or slipping can be eliminated, and stable operation with less wear and tear on parts can be achieved. .

[Brief explanation of drawings]

Fig. 1 is a partially longitudinal front view showing a tool holder according to an embodiment of this invention attached to the main shaft of the machine, Fig. 2 is a partially longitudinal front view showing the same state during indexing, and Fig. 3 is a partial longitudinal cross-sectional view showing the main parts of the tool holder of the same embodiment when removed from the main shaft;
FIG. 4 is a diagram showing the positional relationship between the keyway and the plug in the flange portion, and FIG. 5 is a diagram showing a four-axis tool holder. 1...Shank, 2...Main shaft, 7...Case body, 10...Turret body, 11...Turret shaft, 13...Transmission shaft, 15...Tool rotation axis, 20
... Gear shaft, 23 ... Gear, 24 ... Gear, 25
... Gear, 26 ... Torque transmission mechanism, 29 ... Indexing mechanism, 30 ... Cylinder, 31 ... Indexing shaft, 31a ... Piston, 34 ... Engagement hole, 36
... Connection plate, 38 ... Fluid introduction hole, 44 ... Air discharge port.

Claims (1)

[Scope of utility model registration request] A case body is rotatably supported by a shank that is detachably connected to the drive shaft of a machine tool, and a turret body that rotates around an axis that is inclined with respect to the axis of the shank is attached to the case body. The rotation transmission shaft is rotatably mounted on the turret shaft mounted on the rotation center line of the main body, and
A plurality of tool rotation shafts arranged around the rotation center line are connected to the rotation transmission shaft via a torque transmission mechanism, and a cylinder that drives the indexing shaft movably along the rotation center line is attached to the case body. The turret body is provided with an engagement hole corresponding to the tool rotation axis and into which the indexing shaft engages, and a gear shaft connected to the indexing shaft is provided with a gear that constantly transmits the rotation of the shank to the gear shaft. and a gear connected to the transmission shaft at a position where the indexing shaft engages with the engagement hole;
At the position where the index shaft and the engagement hole are disengaged, attach the gear that connects to the turret shaft, and connect the shank to the drive shaft in the case body, which communicates with the pressurized fluid discharge port provided on the machine tool. A tool holder having a fluid insertion hole and communicating the fluid insertion hole with the cylinder.