JP7443470B1 - Tool support device and machine tool equipped with the tool support device - Google Patents

Abstract

An object of the present invention is to provide a tool support device capable of supporting a hob tool on both sides and a machine tool equipped with the tool support device at low cost. A tool support device 500 includes a rotation support unit 40 that is removably attached to a tool rest 6 while a hob tool 90 is held on a tool rotation member 7, and a rotation support unit 40 that is attached to the tool rest 6. It includes a fixing mechanism section that switches between a fixed state and a released state. The rotation support unit 40 includes a first support engagement part that engages with an engaged part formed on the tool rest 6, and a hob tip engagement part that engages with the tip of the hob tool 90 in a state that allows rotation thereof. A joining part 80 is provided. [Selection diagram] Figure 3

Description

The present invention relates to a tool support device and a machine tool equipped with the tool support device.

2. Description of the Related Art Conventionally, machine tools have been known that create and process tooth profiles on the circumferential surface of a workpiece by synchronously rotating a hob tool held on a tool spindle and a workpiece held on a workpiece spindle. This hob tool is supported by a cantilever on the tool headstock together with the tool spindle.

This type of machine tool may be equipped with a tool exchange device to enable automatic exchange of tools held on a tool spindle (see, for example, Patent Document 1). The tool changer performs a tool change operation between the tool magazine and the tool spindle. In addition to hob tools, the tool magazine stocks various tools such as end mills and milling tools. The tool changer receives a command from the control unit, selects the next process tool from among the multiple tools stocked in the tool magazine, and selects the selected next process tool and the completed machining tool held in the tool spindle. Execute an exchange operation with.

JP2022-017085A

However, in the machine tool shown in Patent Document 1, since the hob tool is cantilever-supported by the tool spindle (first support part) together with the tool spindle (first support part), the rigidity of the hob tool is insufficient and the tooth shape is machining accuracy may be reduced.

Therefore, it is conceivable to prepare a tool assembly in which a hob tool is supported on both sides by a highly rigid support frame, and to hold this entire tool assembly on a tool rotating member.

However, in this case, when exchanging tools, it is necessary to exchange the entire tool assembly using the tool exchanger, which increases the size of the tool exchanger. That is, since the tool assembly is heavier than the tool alone, for example, when changing tools using a rotary tool changing arm, it is necessary to increase the size of the motor for rotating the tool changing arm.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a tool support device capable of supporting a hob tool on both sides, and a machine tool equipped with the tool support device at a low cost.

One aspect of the present invention for solving the above problem is:
a first support part that rotatably supports a hob tool;
a second support portion rotatably supporting a side of the hob tool opposite to the side supported by the first support portion;
The second support part is
a rotation support unit that is removably attached to the first support part with the hob tool supported by the first support part;
a fixing mechanism section for fixing the rotation support unit attached to the first support section to the first support section;
The fixing mechanism section is configured to be able to switch the rotation support unit between a fixed state in which the rotation support unit is fixed to the first support section and a fixed release state in which the fixation is released,
The rotation support unit is
a first support engagement portion that engages with an engaged portion provided on the first support portion when the first support portion is attached to the first support portion;
a hob tip engaging part that engages with the tip of the hob tool in a state that allows rotation thereof;
The present invention relates to a tool support device having:

According to this tool support device, by mounting the rotation support unit on the first support portion, the first support engagement portion provided on the rotation support unit engages with the engaged portion provided on the first support portion. Then, the hob tip engaging portion engages with the tip of the hob tool in a state that allows rotation thereof. As a result, the hob tool is supported by the first support portion and the rotary support unit in a dual-supported state. That is, the base end portion of the hob tool is supported by the first support portion, and the tip portion of the hob tool is supported by the hob tip engaging portion of the rotation support unit. After the rotary support unit is attached to the first support part, the rotary support unit may be fixed to the first support part by the fixing mechanism section and hobbing may be started. This hobbing is performed in a state where the hobbing tool is supported at both ends by the first support portion and the rotation support unit, as described above. Therefore, compared to the case where the hob tool is cantilever-supported only by the first support part, the rigidity of the hob tool can be increased and the machining accuracy of the tooth profile can be improved.

Further, according to the tool support device, the rotation support unit is configured as a separate unit that can be separated from the hob tool. Therefore, even if there are a plurality of replacement hob tools, it is sufficient to prepare one rotational support unit common to the plurality of hob tools. Therefore, it is not necessary to prepare as many rotary support units as there are hob tools, so the number of parts can be suppressed and the hob tool can be supported at both ends with an inexpensive configuration.

The first support section is configured to be movable in a predetermined direction, and the rotation support unit receives the operating force of a predetermined movement operation performed by the first support section when the fixation mechanism section is in the unlocked state. It is preferable that the first support part be detachably attached to the first support part by using the first support part.

According to this configuration, the operation of attaching and detaching the rotary support unit to and from the first support portion can be automatically performed using a predetermined moving operation performed by the first support portion. Therefore, there is no need for the operator to manually attach the rotary support unit to the first support part, which reduces the physical burden on the operator and enables quick switching to the hob tool. I can do it.

The rotary support unit includes a support frame that extends along the length of the hob tool when attached to the first support part, and a tip end of the hob that is supported by the support frame via a bearing. the support frame constitutes one end in the extending direction thereof, has the first support engagement part, and the hob when the rotary support unit is attached. An annular part that annularly surrounds the periphery of the tool, a bearing holding part forming the other end in the extending direction and holding the bearing, and a connecting part connecting the bearing holding part and the annular part. It is preferable to have.

According to this configuration, when the rotary support unit is attached to the first support part, the hob tool is inserted into the first support part or the rotary support unit so that the hob tool penetrates inside the annular part that constitutes one end of the support frame. All you have to do is move it. Then, the first support engagement part provided on the annular part of the support frame is engaged with the engaged part provided on the first support part, and the hob tip engagement part supported by the support frame is activated. By engaging the free rotation member with the tip of the hob tool, attachment of the rotation support unit (support frame) to the first support portion is completed. Therefore, the rotation support unit can be attached to the first support part by a simple linear movement. Further, since the rotation support unit is not offset radially outward with respect to the hob tool, the surrounding space efficiency can be improved.

The engaged portion provided on the first support portion includes an annular tapered surface formed concentrically with the axis of the first support portion, and the first support engagement portion provided on the rotation support unit. preferably comprises an annular tapered surface formed concentrically with the axis of the free rotation member.

According to this configuration, when the rotation support unit is attached to the first support part, the annular tapered surface as the first support engagement part provided in the rotation support unit and the engaged part provided in the first support part are connected to each other. The annular tapered surface serving as the joint portion engages with the annular tapered surface. As a result, the support axis of the first support part and the axis of the free rotation member provided in the rotation support unit are positioned coaxially. This prevents the axis of rotation of the hob tool from tilting, which in turn makes it possible to improve the machining accuracy of the tooth profile with the hob tool.

The fixing mechanism section is provided in the rotation support unit, and when the rotation support unit is attached to the first support section, fluid is supplied through a fluid passage formed inside the first support section. It is preferable that the fixed state and the unfixed state be switchable based on the fluid pressure applied.

According to this, by providing the fixing mechanism part in the rotation support unit, the rotation support unit can be fixed to the first support part without significantly changing the structure of the existing first support part. . Therefore, it is possible to minimize the number of man-hours required for modifying the first support portion to realize double-sided support of the hob tool, and to reduce costs.

The rotation support unit may be attached to an external member attached to the first support section. That is, in the tool support device, the first support portion includes a tool rest, a tool rotating member rotatably supported by the tool rest, and an external member attached and fixed to an outer surface of the tool rest. , the external member has a unit mounting seat at a position offset to the side of the tool rotation member when viewed from the axial direction of the tool rotation member, and the rotation support unit is attached to the first support portion. The hob tool includes a support frame extending along the length of the hob tool in the installed state, and a freely rotating member as the hob tip engagement portion supported by the support frame via a bearing. , the support frame constitutes one end in its extending direction, has the first support engagement portion, and has a seat that abuts the unit mounting seat surface of the external member when the rotation support unit is attached. A surface contacting portion, a bearing holding portion constituting the other end in the extending direction and holding the bearing, and a connecting portion connecting the bearing holding portion and the seat surface contacting portion. It is possible to adopt a mode in which

According to this, the unit mounting seat surface can be secured at a position offset from the tool rotation member by the external member provided on the first support portion. Therefore, there is no need to provide a unit mounting seat surface in the first support section around the tool rotating member, which tends to have a complicated structure. Therefore, the configuration of the first support part can be simplified and costs can be reduced.

Other aspects of the invention include:
The machine tool includes the tool support device,
It has a tool magazine that stocks a plurality of tools that can be attached to the first support part, and a tool exchange arm, and the tool magazine has a tool exchange arm that can exchange the tools held in the tool magazine and the tools held in the first support part. a tool changing device that exchanges tools using the tool changing arm;
a unit accommodating portion that accommodates the rotation support unit;
The first support section is set to a tool exchange position where tools can be exchanged with the tool exchange device, and a unit attachment/detachment position where the rotary support unit can be attached and detached between the unit accommodating section. a movable first support drive section;
comprising a control unit that controls the operation of the first support drive unit, the tool changer, and the fixing mechanism unit,
When the tool changer performs a tool change to the hob tool, the control section positions the first support section at the tool change position using the first support drive section, and then controls the tool change device to change the tool to the hob tool. The hob tool is attached to the first support part supported by the first support part, and after the attachment, with the fixing mechanism part in the unlocked state, the first support driver drives the hob tool. By moving the first support part from the tool exchange position to the unit attachment/detachment position, the rotational support unit is attached to the first support part using the movement force during the movement operation, and after the attachment The present invention relates to a machine tool configured to switch the fixing mechanism section to the fixed state.

According to this machine tool, when the hob tool is used, the hob tool is attached to the first support part by the tool changer under the control of the control unit, and then the first support drive part is used to attach the hob tool to the first support part. is moved to the unit attachment/detachment position. Thereby, the rotation support unit is attached to the first support part, and the hob tool is supported on both sides by the first support part and the rotation support unit. After the attachment of the rotation support unit to the first support part is completed, the rotation support unit is fixed to the first support part by switching the fixing mechanism part from the fixing release state to the fixation state. To attach the rotary support unit to the first support section, a moving force of the first support section to the unit attachment/detachment position is utilized. Therefore, the rotation support unit can be attached to the first support part by using existing equipment (first support drive part) without separately providing a dedicated device (for example, a robot, etc.) for attaching the rotation support unit to the first support part. Can be installed.

When the rotary support unit fixed to the first support unit is attached or detached after the hob tool completes machining of the workpiece, the control unit first causes the first support drive unit to move the rotation support unit to the first support unit. The rotary support unit is accommodated in the unit accommodating portion by moving the rotary support unit to the unit attachment/detachment position, and then the fixation of the rotary support unit is released by the fixing mechanism portion, and the first support drive portion is moved to the unit attachment/detachment position. By moving the first support part away from the unit attachment/detachment position along a predetermined direction, the rotary support unit is attached and detached from the first support part using the movement force at the time of the separation movement. Preferably.

According to this, after the processing of the workpiece by the hob tool is completed, the first support section is moved to the unit attachment/detachment position by the first support drive section under the control of the control section. As a result, the rotation support unit attached to the first support part is housed in the unit housing part. After the rotation support unit is housed in the unit housing section, the fixing mechanism section switches to the fixing release state to release the fixation of the rotation support unit to the first support section, and after the fixation is released, the first support drive section The first support portion is moved away from the unit attachment/detachment position in a predetermined direction. As a result, the rotation support unit is detached from the first support section. To attach and detach the rotary support unit, the movement force generated when the first support section is moved apart is utilized. Therefore, the rotation support unit can be removed from the first support part by using existing equipment (the first support drive part) without separately providing a dedicated device (for example, a robot, etc.) for attaching and detaching the rotation support unit from the first support part. Can be attached and detached.

The machine tool further includes a locking device that can be switched between a locked state in which the rotary support unit housed in the unit accommodating portion is immovably locked and a unlocked state in which the lock is released. It is preferable that

According to this, for example, when the first support part is moved to the unit attachment/detachment position by the first support driving part and when moved away from the unit attachment/detachment position, the rotation support unit is attached to the unit housing part by the locking device. By locking the rotary support unit so that it cannot be moved, the rotation support unit can be smoothly and reliably attached to and detached from the first support portion.

It is preferable that the unit accommodating part is disposed on the opposite side of the tool magazine with the first support part in between.

According to this configuration, the unit accommodating part can be arranged using the dead space located on the opposite side of the tool magazine with the first support part in between.

The machine tool has a partition wall that partitions a processing area in which the first support part is accommodated and a magazine accommodation space in which the tool magazine is accommodated, and the unit accommodation part is arranged in the magazine accommodation space. It may be provided inside.

According to this, by providing the unit accommodating part in the magazine accommodating space, the tool exchange position, which is the movement destination of the first support part when exchanging tools, and the tool exchange position, which is the movement destination of the first support part when exchanging tools, and the tool exchange position when attaching and detaching the rotation support unit to the first support part, The unit attachment/detachment position, which is the destination of the movement of the first support part, can be brought as close as possible. Therefore, the time from when the hob tool is attached to the first support part to when the first support part is moved to the unit attachment/detachment position can be shortened. In turn, cycle time can be shortened and productivity can be improved.

As described above, according to the present invention, the rotary support unit is removably attached to the first support part while the hob tool is held on the first support part, and the rotary support unit is attached to the first support part. The rotation support unit includes a fixing mechanism that switches between a fixed state in which the fixation is fixed and a fixed release state in which the fixation is released. A tool support device that can hold a hob tool on both sides by providing a support engagement part and a hob tip engagement part that engages with the tip of the hob tool in a state that allows rotation of the hob tool, and the tool A machine tool equipped with a support device is provided at low cost.

FIG. 1 is an overall perspective view showing a machine tool to which a tool support device according to a first embodiment is applied. FIG. 2 is a front view showing the tool headstock. FIG. 3 is a side view of the tool support device seen from the right side. FIG. 4 is a perspective view showing the rotation support unit. FIG. 5 is a sectional view taken along the line VV in FIG. 4. FIG. 6 is a schematic diagram showing the configuration of the unit housing section. FIG. 7 is a block diagram showing the configuration of the control system of the machine tool. FIG. 8A is an explanatory diagram for explaining the contents of tool exchange control. FIG. 8B is an explanatory diagram for explaining the contents of tool exchange control. FIG. 8C is an explanatory diagram for explaining the contents of tool exchange control. FIG. 8D is an explanatory diagram for explaining the details of unit installation control. FIG. 8E is an explanatory diagram for explaining the details of unit installation control. FIG. 8F is an explanatory diagram for explaining the details of unit installation control. FIG. 8G is an explanatory diagram for explaining the details of unit installation control. FIG. 8H is an explanatory diagram for explaining the details of unit installation control. FIG. 8I is an explanatory diagram for explaining the details of unit installation control. FIG. 9 is a perspective view showing a tool support device in Embodiment 2. FIG. 10 is a perspective view showing a state in which the rotation support unit in FIG. 9 is removed. FIG. 11 is a plan view showing a unit mounting seat provided on an external member of the tool head stock. FIG. 12 is a perspective view showing a state in which the tool headstock is rotated so that the tip of the hob tool faces the unit accommodating portion in the second embodiment. FIG. 13 is a diagram corresponding to FIG. 12 showing a modification of the second embodiment. FIG. 14 is a diagram corresponding to FIG. 3 showing the third embodiment.

Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

(Embodiment)
FIG. 1 is an overall perspective view showing a machine tool 1 to which a tool support device 500 (see FIG. 3) according to the embodiment is applied. In the following description, the front side, rear side, left side, and right side are directions based on the machine tool 1, and are as shown on the directional axis in FIG. 1.

The machine tool 1 is a compound lathe with five-axis control, and includes a bed 2, a first work spindle 3 and a second work spindle arranged on the bed 2 to face each other in the Z-axis direction (horizontal direction). A turret tool rest 5 is arranged between the table 4, the first work head stock 3 and the second work head stock 4 so as to be movable in the X-axis direction (vertical direction) and the Z-axis direction, and the a tool headstock 6 (an example of a tool rest) arranged to be movable in the direction, the Y-axis direction (back and forth direction), and the Z-axis direction; (an example of a tool rotating member) and a control unit 100 (see FIG. 7) that controls the operation of each part of the machine tool 1. Various tools such as a hob tool 90, an end mill, and a milling tool can be attached to the tool spindle 7 as a tool 9. In the following description, these tools will be referred to as tool 9 unless otherwise distinguished. Further, the tool spindle stock 6 and the tool spindle 7 constitute a first support portion.

On the left side of the processing area S1 for the workpiece W on the bed 2, a tool exchanger 8 is arranged to exchange the tool 9 mounted on the tool spindle 7 with the tool 9 to be used in the next process.
The tool changer 8 has two tool magazines 8a, as will be described later. The two tool magazines 8a are housed in a magazine housing space S2 adjacent to the left side of the processing area S1.

The processing area S1 and the magazine storage space S2 are partitioned by a partition wall 16 arranged vertically along the front-rear direction. At the center of the partition wall 16, an opening 16a for tool exchange and a sliding ATC shutter 17 for opening and closing the opening 16a are provided. In this example, the ATC shutter 17 is configured to be slidable in the vertical direction, but is not limited to this, and may be configured to be slidable in the horizontal direction, for example.

Further, a unit housing portion 20 is provided on the opposite side of the tool changer 8 with the tool headstock 6 interposed therebetween. The unit accommodating portion 20 accommodates a rotation support unit 40, which will be described later, which is attached to the tool headstock 6 during hobbing.

The first workpiece spindle 3 is fixed to the upper surface of the bed 2 and holds the first workpiece spindle 10 rotatably around the C-axis parallel to the Z-axis. On the other hand, the second workpiece spindle 4 holds the second workpiece spindle 11 coaxially with the first workpiece spindle 10 so as to be rotatable around the C-axis. The second work headstock 4 is moved in the Z-axis direction by a feed motor 33a and a feed screw (not shown). The first work spindle 10 is driven by a first spindle motor (not shown), and the second work spindle 11 is driven by a second spindle motor (not shown). During hobbing, the workpiece W is rotated around the C-axis while being supported at both ends by the first workpiece spindle 10 and the second workpiece spindle 11.

The turret tool rest 5 has a turret 5a that can rotate around an axis parallel to the Z-axis, and is configured to be movable in the Z-axis direction and the X-axis direction by a feed motor and a feed screw (none of which are shown). ing. Tools 5b are radially arranged on the outer periphery of the turret 5a at intervals in the circumferential direction.

The tool headstock 6 is connected to a column 12 erected on the upper surface of the bed 2 via a saddle 13, a slider 14, and a ram 15.

The column 12 has a gate shape extending over both left and right ends of the upper surface of the bed 2. The saddle 13 is configured to be movable in the Z-axis direction by slidably engaging a pair of guide rails (not shown) provided on the front side of the column 12. The saddle 13 is driven in the Z-axis direction by a pair of upper and lower feed screws 31 (only one is shown in FIG. 1) and a pair of feed motors 30b.

The slider 14 is configured to be movable in the X-axis direction by slidably engaging with a pair of left and right guide rails (not shown) provided on the front side of the saddle 13. The slider 14 is driven in the X-axis direction by a pair of feed screws 32 (only one of which is shown in FIG. 1) and a pair of feed motors 30c.

The ram 15 is inserted into a ram guide hole 14a formed in the slider 14 and supported by a guide plate (not shown) so as to be movable in the Y-axis direction. This ram 15 is driven in the Y-axis direction by one feed screw and a feed motor (none of which are shown) arranged at the lower end of the slider 14.

Further, the tool headstock 6 is fixed to a swing drive shaft (not shown) rotatably supported by the ram 15. The tool headstock 6 is configured to be able to rotate around the B-axis parallel to the Y-axis by a rotation motor (not shown) connected to the rotation drive shaft.

[Tool change device]
As shown in FIG. 1, the tool exchange device 8 includes two tool magazines 8a lined up in the front-rear direction and a tool exchange arm (not shown). Each tool magazine 8a has an elliptical frame that is elongated in the vertical direction, a chain that goes around the frame, and a plurality of tool pots that are attached to the chain. Each tool pot removably holds various tools 9 such as a hob tool 90, an end mill, and a milling tool. A plurality of hob tools 90 are stocked in the tool magazine 8a for the purpose of replacement when worn or for forming tooth profiles of different shapes.

The tool exchange arm is rotationally driven around an axis parallel to the Z-axis by a motor (not shown). At the time of tool exchange, the ATC shutter 17 is opened and the tool headstock 6 is moved to the tool exchange position (see FIG. 8B, which will be described later). As a result, the tool 9 held by the tool spindle 7 horizontally enters the magazine accommodation space S2. Then, the tool 9 that has entered and the next process tool 9 indexed to a predetermined position by the tool magazine 8a are exchanged by the tool exchange arm.

[Tool headstock]
As shown in FIG. 2, the tool headstock 6 has a pivot housing 6a and a spindle housing 6b.

The rotating housing 6a has a rectangular box shape in appearance. An arc-shaped mounting plate portion 6c is integrally formed on the back surface of the swing housing 6a. A plurality of through holes 6d are formed at intervals in the circumferential direction on the peripheral edge of the mounting plate portion 6c. The mounting plate portion 6c is rotatably fixed to the swing drive shaft by bolts (not shown) inserted through the respective through holes 6d.

The main shaft housing 6b is fixed to the pivot housing 6a with its rotation axis perpendicular to the rotation axis (B axis) of the pivot housing 6a. The main shaft housing 6b is formed into an axially symmetrical cylindrical shape. Inside the spindle housing 6b, there are a bearing that rotatably supports the tool spindle 7, a built-in motor that drives the tool spindle 7, and a drawbar mechanism (none of which are shown) that fixes the tool 9 to the tool spindle 7. etc. are accommodated.

The main shaft housing 6b is attached to the rotating housing 9a so that a portion of its front end side is exposed to the outside. That is, the main shaft housing 6b includes a cylindrical non-exposed portion 6e housed inside the rotating housing 6a, and an externally exposed portion 6f exposed to the outside of the rotating housing 6a.

The externally exposed portion 6f has a flange portion 6g, a large diameter cylindrical portion 6h, and a small diameter cylindrical portion 6i that are lined up from the base end side to the distal end side of the main shaft housing 6b. The flange portion 6g is fixed to the lower surface of the swing housing 6a with bolts (not shown).

An annular groove 6k extending all the way around in the circumferential direction is formed in the stepped surface 6j located at the boundary between the large diameter cylindrical portion 6h and the small diameter cylindrical portion 6i. The inner circumferential surface of the annular groove 6k is an annular tapered surface 6l whose diameter decreases toward the distal end. This annular tapered surface 6l corresponds to an engaged portion formed on the tool post.

The small diameter cylindrical portion 6i has an annular engagement protrusion 6m at the tip of its outer peripheral surface. The annular engagement protrusion 6m slightly protrudes radially outward from the outer peripheral surface of the small diameter cylindrical portion 6i.

[Tool spindle]
As shown in FIG. 2, the tool spindle 7 is supported inside the spindle housing 6b via a bearing (not shown). A tool mounting hole 7a (shown only in FIG. 5 described below) for mounting a tool 9 is formed at the tip of the tool spindle 7. In the example of FIG. 2, a hob tool 90 is illustrated as an example of the tool 9 that is mounted in the tool mounting hole 7a.

[Hob tool]
The hob tool 90 is a tool for hobbing that forms a tooth profile on the circumferential surface of a workpiece W (see FIG. 1) supported by the first workpiece spindle 10 and the second workpiece spindle 11.

As shown in FIG. 2, the hob tool 90 has a tool main body part 91 and a holder part 92. The tool main body portion 91 has a shaft portion 91a and a large diameter blade portion 91b formed coaxially with the shaft portion 91a. The distal end of the shaft portion 91a is formed into a tapered shaft shape whose diameter decreases toward the distal end. The blade portion 91b is a part that processes the workpiece W. The blade portion 91b has a plurality of blade rows depending on the tooth profile to be machined.

The holder portion 92 has the same shape in all tools 9 including the hob tool 90. The holder portion 92 has a flange portion 92a, a shank portion 92b, and a pull bolt 92c.

The flange portion 92a is a portion that is held by the tool changing arm of the tool changing device 8 during tool changing. The flange portion 92a is connected to the tip of the shank portion 92b. The flange portion 92a protrudes outward in the radial direction from the shank portion 92b in a brim shape. A V-shaped gripping groove 92d extending in the circumferential direction is formed on the outer peripheral surface of the flange portion 92a over the entire circumference. At the time of tool exchange, the hob tool 90 is gripped by the tool exchange arm as gripping claws formed at both ends of the tool exchange arm (not shown) engage with the V-shaped grip groove 92d.

The shank portion 92b is formed into a tapered shaft shape that fits into the tool mounting hole 7a. The pull bolt 92c is coaxially connected to the shank portion 92b at its base end. This pull bolt 92c is pulled toward the base end side in the axial direction by a drawbar mechanism housed inside the main shaft housing 6b. Thereby, the shank portion 92b of the hob tool 90 is irremovably fixed to the inner wall surface of the tool mounting hole 7a. In this way, the hob tool 90 is held in a cantilever state with respect to the tool spindle 7 (with only the proximal end portion fixed to the tool spindle 7).

Here, in the machine tool 1 of this example, when performing hobbing, the hobbing tool 90 can be converted from a cantilevered state to a double-supported state by attaching and fixing the rotation support unit 40 to the tool headstock 6. It has become. This rotation support unit 40 and a fixing mechanism section 60, which will be described later, constitute a second support section.

[Rotation support unit]
FIG. 3 is a side view of the rotation support unit 40 mounted on the tool headstock 6, viewed from the right side, and FIG. 4 is an external perspective view of the rotation support unit 40.

The rotation support unit 40 includes a support frame 50 that is removably attached to the tool headstock 6, and a fixing mechanism section 60 (see FIG. 5 described later) for non-removably fixing the support frame 50 to the tool headstock 6. , and a freely rotating member 80 as a hob tip engagement portion held by the support frame 50 via a bearing 70.

The support frame 50 extends along the length of the hob tool 90 when it is mounted on the tool head stock 6 .

Specifically, the support frame 50 includes an annular portion 51, a bearing holding portion 52, and a connecting portion 53.

The annular portion 51 is formed to surround the hob tool 90 at one end of the support frame 50 in the extending direction. The annular portion 51 includes an annular main body portion 51a and an end attachment ring 51b attached to an end of the annular main body portion 51a. The annular main body portion 51a is integrally formed with the bearing holding portion 52 and the connecting portion 53.

As shown in FIG. 5, the end attachment ring 51b is constituted by a separate member from the annular main body portion 51a. The end attachment ring 51b has a cylindrical portion 51c, a spigot portion 51d, and an annular protrusion 51e. The spigot part 51d and the annular protrusion 51e are formed coaxially with the cylindrical part 51c along its inner edge, with the spigot part 51d protruding toward the distal end in the axial direction, and the annular protrusion 51e at the proximal end in the axial direction. protrudes to the side. The pilot part 51d fits into the inner circumferential surface of the annular main body part 51a. The annular protrusion 51e has an annular tapered surface 51f (an example of a first support engagement part). The annular tapered surface 51f constitutes the inner circumferential surface of the annular protrusion 51e, and its diameter decreases from the base end side to the distal end side in the axial direction. The annular tapered surface 51f engages with an annular tapered surface 6l provided on the tool head stock 6 side.

The bearing holding portion 52 is arranged with an interval in the axial direction with respect to the annular portion 51. The bearing holding part 52 is arranged perpendicularly to the axis of the annular part 51. A bearing mounting hole 52a is formed through the bearing holding portion 52. The bearing mounting hole 52a is formed coaxially with the annular portion 51. A pair of bearings 70 are fitted into the bearing mounting hole 52a, spaced apart from each other in the axial direction.

The free rotation member 80 includes a cylindrical portion 80a inserted into the inner rings of the pair of bearings 70, and a flange portion 80b formed at the lower end of the cylindrical portion 80a. The flange portion 80b regulates the axial position of the free rotation member 80 with respect to the pair of bearings 70. The free rotation member 80 is fixed to the pair of bearings 70 so as not to fall off by a nut 81 provided on the opposite side of the flange portion 80b. The free rotation member 80 is thus rotatably held by the bearing holding section 52 via the pair of bearings 70. A tip engagement hole 80c that engages with the tip of the hob tool 90 is formed in the end surface of the free rotation member 80 on the annular portion 51 side. The tip engaging hole 80c is formed into a tapered hole shape corresponding to the shape of the tip of the hob tool 90.

The connecting portion 53 is a portion that connects the annular portion 51 and the bearing holding portion 52. Specifically, the connecting portion 53 is constituted by a rectangular column extending parallel to the axis of the annular portion 51 . The connecting portion 53 connects one location in the circumferential direction of the annular portion 51 and the edge portion of the bearing holding portion 52. In this example, the connecting portion 53 is composed of one rectangular column, but is not limited to this. That is, the connecting portion 53 is not limited to a rectangular column, and may be, for example, trapezoidal plate-shaped or circular arc-shaped, and the number of connecting portions 53 is not limited to one, but may be two or more.

[Fixing mechanism part]
As shown in FIG. 5, the fixing mechanism section 60 is provided inside the annular section 51 of the support frame 50.

The fixing mechanism section 60 includes a sliding ring 61 that slides in the axial direction along the inner guide surface 51g of the end attachment ring 51b, and an annular fixing ring 62 fixed to the distal end surface of the end attachment ring 51b. It has a flexible ring 63 disposed inside the sliding ring 61 and a retaining ring 64 that holds the flexible ring 63 so that it cannot fall off.

An annular hydraulic chamber U0 is formed by the end mounting ring 51b, the fixed ring 62, and the sliding ring 61. This hydraulic chamber U0 is composed of a first hydraulic chamber U1 and a second hydraulic chamber U2 that face each other with a piston protrusion 61a formed on the outer peripheral surface of the sliding ring 61 interposed therebetween.

The flexible ring 63 includes a ring main body 63a, a plurality of flexible pieces 63b whose base ends are connected to the ring main body 63a, and an engaging claw portion formed at the tip of each flexible piece 63b. 63c. The ring body portion 63a is held by fitting into a holding groove 64a formed in the holding ring 64. The flexible piece portion 63b is in contact with the inner peripheral surface of the sliding ring 61.

When hydraulic pressure is supplied to the first hydraulic chamber U1, the piston protrusion 61a provided on the sliding ring 61 is pushed to the right in FIG. 5, and the entire sliding ring 61 moves to the right. As a result, the flexible piece portion 63b falls radially inward using its base end as a fulcrum. As a result, the engagement claw 63c formed at the tip of the flexible piece 63b engages with the annular engagement protrusion 6m formed at the tip of the main shaft housing 6b. Thereby, the main shaft housing 6b and the rotation support unit 40 are connected (fixed) inseparably in the axial direction.

On the other hand, when hydraulic pressure is supplied to the second hydraulic chamber U2, the piston protrusion 61a provided on the sliding ring 61 is pushed to the left in FIG. 5, and the entire sliding ring 61 moves to the left. As a result, the flexible piece portion 63b expands radially outward using its base end portion as a fulcrum due to the restoring force. As a result, as shown by the solid line in FIG. 5, the engagement claw 63c formed at the tip of the flexible piece 63b engages with the annular engagement protrusion 6m formed at the tip of the main shaft housing 6b. is released. As a result, the axial connection (fixation) between the main shaft housing 6b and the rotation support unit 40 is released.

In this way, the fixing mechanism section 60 is configured to be able to switch the rotation support unit 40 between a fixed state in which it is fixed to the tool spindle stock 6 (specifically, the spindle housing 6b) and a fixed release state in which the fixation is released. has been done.

Hydraulic pressure supply paths L1 and L2 to the first hydraulic chamber U1 and the second hydraulic chamber U2 are established by mounting the rotation support unit 40 on the main shaft housing 6b. That is, two hydraulic supply channels (not shown) for supplying hydraulic oil to the respective hydraulic chambers U1 and U2 are formed in the main shaft housing 6b, and when the rotation support unit 40 is attached to the main shaft housing 6b, these two hydraulic supply flow paths (not shown) are formed in the main shaft housing 6b. Two hydraulic supply passages communicate with two hydraulic supply passages (not shown) formed in the end mounting ring 51b of the rotary support unit 40. Thereby, the hydraulic pressure supply paths L1 and L2 are established.

[Unit housing]
The rotation support unit 40 is housed in the unit housing section 20 while hobbing is not being performed. The rotation support unit 40 is attached to the tool headstock 6 by moving the tool headstock 6 in the left-right direction as described later.

The unit accommodating portion 20 is formed in a rectangular box shape and is arranged above the second work headstock 4 . The unit housing portion 20 is fixed to the bed 2 of the machine tool 1 via a connecting plate 21. The connecting plate 21 and the lower surface of the unit accommodating portion 20 are connected by reinforcing ribs 22 .

As shown in FIG. 6, a first support section 23 and a second support section 24 that support the rotary support unit 40 are provided upright on the bottom wall 20c of the unit accommodating section 20.

The rotation support unit 40 is mounted above the first support section 23 and the second support section 24 in a state where the axis of the annular section 51 is parallel to the Z-axis and the connection section 53 is located on the near side when viewed from the front of the machine tool 1. will be placed on.

Furthermore, a unit locking device 25 for locking the rotary support unit 40 placed above the first support portion 23 and the second support portion 24 is provided within the unit housing portion 20 .

The unit locking device 25 includes a pair of engagement pins 25a, a holding plate 25b that holds the pair of engagement pins 25a, and a cylinder 25c that moves the holding plate 25b back and forth. The holding plate 25b is moved between a locking position and a locking release position by a cylinder 25c. At the locking position, the pair of engagement pins 25a engage with the pair of engagement holes 25d formed in the support frame 50. As a result, the entire rotary support unit 40 including the support frame 50 is locked so as not to be movable in the left-right direction (Z-axis direction). On the other hand, in the unlocked position, the pair of engagement pins 25a are separated from the support frame 50, so that the rotation support unit 40 can move in the left-right direction (Z-axis direction).

A rectangular opening 20b is formed in the left side wall 20a of the unit accommodating portion 20. The rotation support unit 40 is taken in and out of the unit housing section 20 through this opening 20b.

[Control system configuration]
As shown in FIG. 7, the machine tool 1 has a control section 100 that controls its overall operation. The control unit 100 includes a computer having a CPU, ROM, and RAM.

The control unit 100 includes a spindle rotation drive unit 101, a feed drive unit 102, a spindle rotation drive unit 103, the automatic tool changer (ATC) 8, a shutter drive unit 104, a hydraulic supply device 105, and the unit locking unit. It is connected to the device 25 so that signals can be sent and received.

The spindle rotation drive unit 101 includes a built-in motor for driving the tool spindle 7 described above.

The feed drive unit 102 includes a feed motor (for example, the above-mentioned feed motors 30a to 30c) for realizing relative movement between the workpiece W and the tool 9 in the X-axis direction, the Y-axis direction, and the Z-axis direction. There is. The feed drive section 102 corresponds to a first support drive section.

The spindle rotation drive section 103 includes a rotation motor for rotating the tool headstock 6 described above about the B axis.

The shutter drive unit 104 includes a motor for driving the ATC shutter 17 to open and close.

The hydraulic pressure supply device 105 switches the fixing mechanism section 60 between a fixed state and a fixed release state by controlling the supply of hydraulic oil to the hydraulic pressure supply paths L1 and L2 (see FIG. 5).

The control unit 100 executes machining control of the workpiece W based on an NC program stored in a ROM or the like. When the control unit 100 extracts a tool exchange command from the NC program being executed, the control unit 100 causes the tool exchange device 8 to execute tool exchange control. In this tool exchange control, as described above, the tool exchange arm is used to exchange tools between the tool spindle 7 and the tool magazine 8a.

In addition, when the control unit 100 extracts the tool 9 exchange command from the NC program and determines that the next process tool specified by the tool exchange command is the hob tool 90, the control unit 100 performs the tool exchange control after execution of the tool exchange control. , executes unit mounting control for mounting and fixing the rotation support unit 40 on the tool headstock 6. After the machining operation using the hob tool 90 is completed, the control section 100 executes unit attachment/detachment control for attaching/detaching the rotation support unit 40 from the tool headstock 6.

[Tool exchange control and unit installation control]
8A to 8I are explanatory diagrams for explaining the contents of tool exchange control (FIGS. 8A to 8C) and unit attachment control (FIGS. 8D to 8I) to the hob tool 90. The thick arrow in each figure indicates the next action to be performed.

FIG. 8A shows a state in which a predetermined tool 95 other than the hob tool 90 is attached to the tool spindle 7 (see FIG. 2) supported by the tool spindle stock 6.

In the tool change control for the hob tool 90, under the control of the control section 100, the ATC shutter 17 is moved to the open position by the shutter drive section 104, and the tool headstock 6 is moved to the feed drive section 102 and the spindle rotation drive section 103. to the above-mentioned tool exchange position (see FIG. 8B).

After this movement is completed, the tool exchange device 8 executes a tool exchange between the hob tool 90, which is the next process tool stored in the tool magazine 8a, and the predetermined tool 95 mounted on the tool spindle 7. Then, the hob tool 90 mounted on the tool spindle 7 due to tool exchange is fixed to the tool spindle 7 by the drawbar mechanism (see FIG. 8C).

After the attachment and fixation of the hob tool 90 to the tool spindle 7 is completed, unit attachment control is executed as shown in FIGS. 8D to 8I. In unit mounting control, first, under the control of the control section 100, the tool headstock 6 is retracted to the right side by the feed drive section 102, and the ATC shutter 17 is moved to the closed position by the shutter drive section 104 (Fig. 8D reference).

Next, the tool headstock 6 is rotated by 180° counterclockwise in FIG. 8D by the spindle rotation drive section 103. This brings the tip of the hob tool 90 into a state where it faces the opening 20b of the unit accommodating portion 20 (FIG. 8E). In the state of FIG. 8E, the axis of the hob tool 90 is coaxial with the annular portion 51 of the rotation support unit 40 housed in the unit housing section 20. Note that depending on the device configuration, it may not be possible to be coaxial, but in that case, the position of the tool headstock 6 may be adjusted by the feed drive section 102.

Then, after the axis of the hob tool 90 and the axis of the annular part 51 of the rotation support unit 40 become coaxial, the fixing mechanism part 60 is released from fixation by the hydraulic supply device 105 (the state shown in FIG. 5). While maintaining the position, the tool headstock 6 is horizontally moved to the right by the feed drive section 102 to the unit attachment/detachment position (see FIG. 8F).

Due to this movement of the tool headstock 6 to the unit attachment/detachment position, the annular tapered surface 51f (see FIG. 5) provided on the annular portion 51 of the rotation support unit 40 changes from the annular tapered surface 6l provided on the tool headstock 6. engage with. Further, the tip of the hob tool 90 passes through the inside of the annular portion 51 and engages with the tip engagement hole 80c of the free rotation member 80. Then, after this engagement is completed (in other words, after the rotation support unit 40 is completely attached to the tool headstock 6), the fixing mechanism section 60 is switched to the fixed state by the hydraulic pressure supply device 105. As a result, the rotation support unit 40 is fixed to the tool head stock 6 in a manner that cannot be separated.

After the rotation support unit 40 is fixed to the tool head stock 6, the holding plate 25b is moved to the unlocked position by the unit locking device 25 (see FIG. 8G). In this state, the rotation support unit 40 is pulled out from the unit accommodating part 20 by retracting the tool headstock 6 toward the left side by the feed drive part 102. This completes the attachment of the rotation support unit 40 to the tool headstock 6.

After the rotation support unit 40 has been attached, the tool spindle stock 6 is rotated counterclockwise by the spindle rotation drive section 103 (see FIG. 8I). Then, by rotating the tool spindle 7 in synchronization with the work W, a tooth profile is formed on the circumferential surface of the work W.

The unit attachment control has been explained above, but the unit attachment/detachment control (control for removing the rotation support unit 40 from the tool headstock 6) is an operation in the reverse order of the unit attachment control (that is, FIG. 8I → FIG. 8H → FIG. 8G→...operation proceeding in the order of FIG. 8A), detailed explanation will be omitted here.

[Effect]
As explained above, the tool support device 500 (see FIG. 9) of the present embodiment includes the rotation support unit 40, and the rotation support unit 40 includes the annular tapered surface 6l (engaged) provided on the tool headstock 6. an annular tapered surface 51f (an example of a first support engagement part) that engages with a joint (an example of a joint); and a free rotating member 80 (an example of a hob tip engagement part) that engages with a tip of a hob tool 90 in a state that allows rotation thereof. (an example of a joint).

According to this, the hob tool 90 is supported by the tool headstock 6 and the free rotation member 80 provided in the rotation support unit 40 in a dual-supported state. Therefore, compared to the case where the hob tool 90 is cantilever-supported only by the tool headstock 6, the rigidity of the hob tool 90 can be increased and the machining accuracy of the tooth profile can be improved. Further, since the rotation support unit 40 is a separate unit from the hob tool 90, it is sufficient to prepare one rotation support unit 40 common to the plurality of hob tools 90 stocked in the tool magazine 8a. . Therefore, it is not necessary to prepare as many rotary support units 40 as there are hob tools 90, so the number of parts can be suppressed and the hob tool 90 can be supported at both ends with an inexpensive configuration.

Further, the tool headstock 6 is configured to be movable in the left-right direction (an example of a predetermined direction). Then, the rotation support unit 40 uses the operating force of the linear movement movement (predetermined movement movement) to the right side performed by the tool headstock 6 while the fixation mechanism section 60 is in the unlocked state. 6 (see FIGS. 8E to 8H).

According to this, the operation of attaching and detaching the rotation support unit 40 to and from the tool headstock 6 can be automatically performed using the linear movement movement to the right performed by the tool headstock 6. Therefore, there is no need for the operator to manually attach the rotation support unit 40 to the tool headstock 6. Therefore, it is possible to reduce the physical burden on the worker and to quickly switch to the hob tool 90. Furthermore, since there is no need to separately provide a dedicated robot or the like for mounting the rotation support unit 40 on the tool headstock 6, the rotation support unit 40 can be mounted on the tool headstock 6 with an inexpensive configuration.

In the present embodiment, the rotation support unit 40 includes a support frame 50 that extends along the length of the hob tool 90 when mounted on the tool headstock 6, and a support frame 50 that is connected to the support frame 50 via a bearing 70. The free rotating member 80 is supported. The support frame 50 constitutes one end in its extending direction, has the annular tapered surface 51f, and constitutes an annular portion 51 that annularly surrounds the hob tool 90, and the other end in its extending direction. It has a bearing holding part 52 that holds the bearing 70, and a connecting part 53 that connects the bearing holding part 52 and the annular part 51.

According to this, when mounting the rotation support unit 40 on the tool headstock 6, the tool headstock 6 is mounted so that the hob tool 90 passes through the inside of the annular portion 51 that constitutes one end of the support frame 50. Just move it. Therefore, the rotation support unit 40 can be attached to the tool headstock 6 by simple linear movement. Moreover, since the rotation support unit 40 is not offset radially outward with respect to the hob tool 90, space efficiency around the tool can be improved.

The annular tapered surface 6l provided on the tool spindle stock 6 is formed concentrically with the axis of the tool spindle 7. Further, the annular tapered surface 51f provided on the support frame 50 is formed concentrically with the axis of the free rotation member 80.

According to this, when the rotation support unit 40 is mounted on the tool headstock 6, the annular tapered surface 6l provided on the tool headstock 6 and the annular tapered surface 51f provided on the support frame 50 engage with each other. As a result, the axis of the tool spindle 7 provided on the tool spindle stock 6 and the axis of the freely rotating member 80 provided on the rotation support unit 40 are positioned coaxially. This prevents the axis of rotation of the hob tool 90 from inclining, which in turn makes it possible to improve the accuracy of tooth profile machining by the hob tool 90.

Further, the fixing mechanism section 60 is provided in the rotation support unit 40. When the rotation support unit 40 is attached to the tool headstock 6, the fixing mechanism section 60 is operated by being supplied via a hydraulic pressure supply path (an example of a fluid passage) formed inside the tool headstock 6. It is configured to be able to switch between a fixed state and a fixed release state based on the oil pressure.

According to this, by providing the fixing mechanism section 60 in the rotation support unit 40, the rotation support unit 40 can be fixed to the tool headstock 6 without significantly changing the structure of the existing tool headstock 6. be able to. Therefore, the number of man-hours required for modifying the tool head stock 6 to realize dual-end support of the hob tool 90 can be minimized, and costs can be reduced.

Further, a unit locking device 25 is provided within the unit housing portion 20 . The unit locking device 25 is configured to be switchable between a locked state in which the rotary support unit 40 is immovably locked and a unlocked state in which the lock is released.

According to this, when the tool headstock 6 is moved to the unit attachment/detachment position by the feed drive part 102 and when moved away from the unit attachment/detachment position, the rotation support unit 40 is moved to the unit housing part 20 by the unit locking device 25. By being immovably locked to the tool head stock 6, the rotation support unit 40 can be smoothly and reliably attached to and detached from the tool head stock 6.

Further, the unit housing section 20 is disposed on the opposite side of the tool magazine 8a with the tool headstock 6 interposed therebetween.

According to this, the unit accommodating portion 20 is stored using the dead space located on the opposite side of the tool magazine 8a across the tool headstock 6 (in this embodiment, the space above the second workpiece headstock 4). can be placed. Therefore, by adding the unit accommodating portion 20, it is possible to prevent the machine tool 1 from increasing in size.

(Embodiment 2)
FIG. 9 shows a second embodiment. This embodiment differs from the first embodiment in that the rotation support unit 240 is attached to an external member 6p of the tool headstock 6. In the following embodiments, the same components as in Embodiment 1 are given the same reference numerals, and detailed explanation thereof will be omitted.

That is, the tool headstock 6 of this embodiment has an external member 6p attached as an option.
The rotation support unit 240 is attached and fixed to this external member 6p via a pull bolt 203.

[External components]
As shown in FIG. 10, the external member 6p is fixed to the front side of the pivot housing 6a of the tool head stock 6 with bolts. A disk-shaped mounting seat 6n for mounting an external member 6p is provided on the front side surface of the rotating housing 6a.

The external member 6p is made of a substantially hexagonal prism having a thickness in the front-rear direction. The external member 6p is arranged such that the lower end surface of the external member 6p is horizontal in a reference state in which the axis of the tool spindle 7 is oriented vertically. This lower end surface functions as a unit mounting seat surface 6q for mounting the rotation support unit 240. The unit mounting seat surface 6q is arranged at a position offset to the front side when viewed from the axial direction of the tool spindle 7.

As shown in FIG. 11, four clamp holes 6r are provided in the unit mounting seat surface 6q.

Each clamp hole 6r is provided in each of the four clamp devices 65 built into the external member 6p. Each clamp device 65 is a ball lock type hydraulic clamp device, and pulls in and clamps the pull bolt 203 (see FIG. 12) inserted into the clamp hole 6r by a hydraulically driven ball lock mechanism.

A hydraulic pressure supply channel (not shown) for supplying hydraulic pressure to each clamp device 65 is formed inside the external member 6p. Control of the supply of hydraulic oil to each clamp device 65 is executed by the hydraulic pressure supply device 105 that receives a command from the control section 100. Note that when the hydraulic pressure supply to each clamp device 65 is stopped, the ball lock is released by a biasing member (not shown) and the clamp device 65 enters an unclamped state.

[Rotation support unit]
As shown in FIG. 12, the rotation support unit 240 is housed in the unit accommodating portion 20 when not in use (when hobbing is not performed), as in the first embodiment. In addition, in FIG. 12, the unit locking device 25 provided in the unit accommodating portion 20 is omitted for ease of viewing.

As shown in FIGS. 9 and 12, the rotation support unit 240 includes a support frame 250 and a free rotation member 260.

The support frame 250 includes a rectangular block-shaped seat contact portion 251 that contacts the unit mounting seat surface 6q of the external member 6p, a rectangular plate-shaped bearing holding portion 252 that holds the free rotation member 260, and a seat contact portion 251 that contacts the unit mounting seat surface 6q of the external member 6p. It has an inclined beam-shaped connecting portion 253 that connects the contact portion 251 and the bearing holding portion 252.

The seat contact portion 251 has a contact seat surface 251a (see FIG. 12) that contacts the unit mounting seat surface 6q. Pull bolts 203 are provided protruding from the four corners of the abutting seat surface 251a.

The configurations of the bearing holder 252 and the free rotation member 260 are the same as those of the bearing holder 52 and the free rotation member 80 described in Embodiment 1, so a detailed explanation will be omitted.

[Unit installation control]
The basic operation of unit mounting control in this embodiment is the same as in the first embodiment, so only the differences will be described. In this example, when the tool headstock 6 is driven to the right from the state shown in FIG. 12 (corresponding to FIG. 8E of Embodiment 1) to the unit attachment/detachment position, the abutting seat surface of the rotation support unit 240 Four pull bolts 203 protruding from 251a engage with clamp holes 6r formed in an external member 6p of the tool headstock 6. After this engagement, each clamp device 65 clamps the pull bolt 203, thereby fixing the rotary support unit 240 to the external member 6p inseparably.

In this embodiment, the clamp hole 6r corresponds to an engaged part formed in the tool headstock 6, which is a tool rest, and the pull bolt 203 engages with an engaged part formed in the tool rest. This corresponds to the first support engagement portion. Further, the clamp device 65 corresponds to a fixing mechanism section.

Note that the unit attachment/detachment control only needs to be performed in the reverse order of the unit attachment control, so a detailed explanation will be omitted here.

[Effect]
As explained above, in this embodiment, the tool headstock 6 has an external member 6p that is attached and fixed to the outer surface thereof. The external member 6p has a unit mounting seat surface 6q at a position offset to the front side (an example of the side of the tool spindle 7) when viewed from the axial direction of the tool spindle 7.

According to this, the unit mounting seat surface 6q can be secured at a position offset from the tool spindle 7 by the external member 6p provided on the tool spindle stock 6. Therefore, there is no need to secure a unit mounting seat surface 6q around the tool spindle 7, which tends to have a complicated structure, in the tool spindle stock 6. Therefore, modifications and additional machining of the tool headstock 6 can be kept to a minimum and costs can be suppressed.

(Modification of Embodiment 2)
FIG. 13 shows a modification of the second embodiment. This modification differs from the second embodiment in that a protection plate 300 can be attached to the unit mounting seat surface 6q of the external member 6p.

The protection plate 300 has a rectangular plate shape. Pull bolts 301 are provided protruding from the four corners of the protection plate 300.

The protection plate 300 is accommodated in the protection plate accommodating section 26 provided below the unit accommodating section 20 during hobbing. After hobbing is completed and the rotary support unit 240 is accommodated in the unit accommodating portion 20, the tool headstock 6 is moved along the path indicated by the two-dot chain arrow in FIG. As a result, each clamp hole 6r of the unit mounting seat surface 6q engages with each pull bolt 301 provided on the protection plate 300. By clamping the pull bolts 301 with each clamp device 65 in this state, the protection plate 300 is mounted and fixed on the unit mounting seat surface 6q. Note that a locking device (not shown) for locking the protection plate 30 is provided in the protection plate accommodating portion 26 with the same concept as the locking device of the rotation support unit 40.

According to this modification, the protection plate 300 is attached and fixed to the unit mounting seat surface 6q of the external member 6p while hobbing is not being performed. Therefore, when processing other than hobbing is being performed, it is possible to prevent chips from adhering to the unit mounting seat surface 6q or from entering the clamp hole 6r.

(Embodiment 3)
FIG. 14 shows the third embodiment. In this embodiment, the installation location of the unit accommodating portion 20 is different from the first and second embodiments.

That is, in this embodiment, the unit accommodating section 20 is provided within the magazine accommodating space S2. The solid line in the figure shows the state in which the tool headstock 6 has been moved to the tool exchange position, and the two-dot chain line in the figure shows the state in which the tool headstock 6 has been moved to the unit attachment/detachment position.

As can be seen from this figure, in this embodiment, the tool exchange position and the unit attachment/detachment position can be brought as close as possible, so that after the hob tool 90 is mounted on the tool spindle 7, the rotary support unit 240 is attached to the tool spindle stock 6. It can shorten the time it takes to install the Therefore, processing cycle time can be shortened and productivity can be improved.

(Other embodiments)
In the embodiment described above, the hob tool 90 is held on the tool spindle 7 supported by the tool spindle rest 6, but the hob tool 90 is not limited to this. For example, the hob tool 90 is held on the tool spindle supported on the turret tool rest 5. A hob tool may also be held. In this case, for example, it is conceivable to configure the turret tool rest 5 to be movable in the front-rear direction (Y-axis direction), and to arrange the unit accommodating portion 20 on the front side or the rear side of the turret tool rest 5. As a result, the rotation support unit 240 can be attached to and removed from the turret tool rest 5 by moving the turret tool rest 5 in the front-rear direction. In this case, the turret tool rest 5 corresponds to the tool rest in the present invention.

Further, in the embodiment, the hob tip engaging portion that engages with the tip of the hob tool 90 is constituted by the free rotating member 80 supported by the bearing 70, but is not limited to this, for example. It may be configured with a conical engagement and fixing member. In this case, for example, the top of the engaging and fixing member may be engaged with a small diameter hole formed in the tip end surface of the hob tool 90. Thereby, the contact area between the hob tool 90 and the engagement fixing member can be reduced as much as possible to suppress frictional resistance, while the tip of the hob tool 90 can be rotatably supported by the engagement fixation member.

In the embodiment, the fixing mechanism section 60 is attached to the rotation support unit 240, but the fixing mechanism section 60 is not limited to this, and may be attached to the tool headstock 6, for example. Further, the fixing mechanism section 60 is not limited to the hydraulic drive type as explained in the above embodiment, but may also adopt a configuration using an electric arm, for example, or a configuration using a magnetic attraction force. Good too.

In the embodiment described above, the annular portion 51 of the support frame 50 is composed of two members, the annular main body portion 51a and the end attachment ring 51b, but is not limited to this. may be formed integrally with the annular main body portion 51a.

Note that the description of the embodiments described above is illustrative in all respects and is not restrictive. Modifications and changes can be made as appropriate by those skilled in the art. The scope of the invention is indicated by the claims rather than the embodiments described above. Furthermore, the scope of the present invention includes changes from the embodiments within the scope of the claims and equivalents.

1: Machine tool 6: Tool headstock (turret, first support part)
7: Tool spindle (first support part)
6l: Annular tapered surface (engaged part)
6p: External member 6q: Unit mounting seat surface 6r: Clamp hole (engaged part)
8: Tool exchange device 8a: Tool magazine 9: Tool 16: Partition wall 20: Unit housing section 40: Rotation support unit (second support section)
50: Support frame 51: Annular portion 51f: Annular tapered surface (first support engagement portion)
52 : Bearing holding part 53 : Connecting part 60 : Fixing mechanism part 65 : Clamp device (fixing mechanism part, second support part)
70: Bearing 80: Free rotating member 90: Hob tool 100: Control section 102: Feed drive section (first support drive section)
203: Pull bolt (first support engagement part)
240: Rotation support unit 250: Support frame 251: Seat contact portion 252: Bearing holding portion 253: Connection portion 260: Free rotation member 500: Tool support device S1: Machining area S2: Magazine storage space W: Workpiece

Claims (11)

a tool spindle that holds a hob tool ;
a tool spindle that rotatably holds the tool spindle;
a holding mechanism for holding the hob tool on the tool spindle;
a tool spindle drive unit that rotates the tool spindle;
A workpiece spindle that holds the workpiece,
a workpiece spindle that rotatably holds the workpiece spindle;
a workpiece spindle drive unit that rotates the workpiece spindle;
a feed drive unit that relatively moves the tool headstock and the workpiece headstock;
A machine tool comprising a control device for controlling the tool spindle drive section, the workpiece spindle drive section, and the feed drive section,
The hob tool is provided in a removable manner with respect to the tool spindle, and rotatably supports a non-retained end of the hob tool held on the tool spindle by the holding mechanism while being attached to the tool spindle. a support frame that
a fixing mechanism for fixing the support frame attached to the tool headstock to the tool headstock without intervening the hob tool ;
The fixing mechanism is configured to be switchable between a fixed state in which the support frame is irremovably fixed to the tool head stock and a fixed release state in which the fixation is released ,
The control device drives the holding mechanism to hold the hob tool on the tool spindle, and then supports a non-holding end of the hob tool while the hob tool is mounted on the tool spindle. The support frame is fixed to the tool spindle by driving the fixing mechanism, and then the tool spindle drive section, the workpiece spindle drive section, and the feed drive section are controlled to fix the workpiece held on the workpiece spindle. A machine tool configured to machine. The control device moves the tool spindle in a predetermined direction with the fixing mechanism in the unlocked state, and uses the operating force accompanying the movement to move the support frame to the tool spindle. The machine tool according to claim 1, wherein the machine tool is configured to be attached to and detached from a base . The support frame is
an annular portion that engages with an engaged portion formed on the tool spindle when mounted on the tool spindle and surrounds the hob tool held on the tool spindle ; ,
a support part having a bearing and rotatably supporting the non-retained end of the hob tool held by the tool spindle by the bearing ;
The machine tool according to claim 1 or 2, further comprising a connecting portion connecting the supporting portion and the annular portion. The engaged portion provided on the tool spindle has an annular tapered surface formed concentrically with the axis of the tool spindle ,
The annular portion of the support frame has an annular tapered surface formed concentrically with the axis of the bearing ,
4. The machine tool according to claim 3 , wherein the annular tapered surface of the annular portion is configured to fit into the annular tapered surface of the engaged portion . The fixing mechanism is configured such that when the support frame is attached to the tool headstock , the fixed state and the The machine tool according to claim 1 or 2, wherein the machine tool is configured to be switchable between a fixing release state and a fixing release state. The tool spindle has a mounting portion formed on its outer surface , and the mounting portion has a mounting seat at a position radially offset from the tool spindle when viewed from the axial direction of the tool spindle . has a surface and an engaged portion provided on the mounting seat surface ,
The support frame is
a seat surface contact that engages with an engaged portion formed on a mounting seat surface of the mounted portion and abuts the mounting seat surface when mounted on the mounted portion of the tool headstock; Department and
a support part having a bearing and rotatably supporting the non-retained end of the hob tool held by the tool spindle by the bearing;
The machine tool according to claim 1 or 2, further comprising a connecting portion that connects the support portion and the seat surface contact portion. A tool magazine that accommodates a plurality of tools including the hob tool that can be attached to the tool spindle, and a tool exchange arm , the tools held in the tool magazine and the tools held in the tool spindle . a tool changing device that changes the tool using the tool changing arm;
further comprising a housing section that houses the support frame ;
The feed drive section is configured to attach and detach the support frame between the tool headstock and the tool exchange position where tools can be exchanged with the tool exchange device and the housing section. configured to be moved into possible attachment/detachment positions;
When mounting the hob tool housed in the tool magazine on the tool spindle , the control device moves the tool spindle to a tool exchange position by the feed drive section, and then moves the tool exchanger to the tool spindle. The hob tool stored in the tool magazine is mounted on the tool spindle , and after mounting, the feed drive unit moves the tool spindle from the tool exchange position to the attachment/detachment position , and the movement The support frame, in which the fixing mechanism is in an unlocked state , is attached to the tool head stock using the operating force accompanying the fixing mechanism , and after the attachment , the fixing mechanism is switched to the fixed state. The machine tool according to claim 1 . When the support frame fixed to the tool headstock is removed after machining of the workpiece by the hob tool is completed, the control device first causes the feed drive unit to move the tool headstock to the tool headstock. After moving the support frame to the attachment/detachment position and storing the support frame in the housing section, the fixation of the support frame by the fixing mechanism is released , and then the feed drive section The machine tool according to claim 7, wherein the support frame is removed from the tool headstock by moving the tool headstock away from the attachment/detachment position. The apparatus further includes a locking device capable of switching between a locking state in which the support frame housed in the housing portion is immovably locked and a locking release state in which the support frame is released. The machine tool according to claim 8. The machine tool according to any one of claims 7 to 9, wherein the accommodating portion is disposed on the opposite side of the tool headstock with respect to the tool magazine. The tool has a partition wall that partitions a machining area that is a space in which the tool spindle is located and a magazine storage space in which the tool magazine is stored, and the storage part is provided in the magazine storage space. The machine tool according to any one of claims 7 to 9.

Images