JPH0354807Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a spindle device for a machine tool equipped with an automatic tool changer.

Prior Art In this type of spindle device, when exchanging a tool holder, the spindle is moved to a tool exchange position, the tool holder is gripped by an exchange arm, and then the drawbar is moved against a disc spring by a cylinder or the like. Push the spindle forward to release the tool holder clamp,
In this state, the tool holder is pulled out from the spindle using the exchange arm, and when the tool holder is attached to the spindle, the reverse operation is performed.In any case, it takes a long time to change the tool. Ta.

To solve this problem, the tool holder is always
A fall prevention mechanism that elastically engages is provided on the spindle, and when exchanging tools, before the exchange arm grasps the tool holder, that is, while the spindle head is moving to the tool exchange position,
Japanese Utility Model Application Publication No. 138513/1984 discloses a device in which the tool holder is unclamped and held by a fall prevention mechanism, and when it is gripped by an exchange arm, the tool holder is immediately removed from the spindle. ing.

Problems to be Solved by the Invention In the conventional mounting described above, the falling-off prevention mechanism is always elastically engaged with the tool holder, so this mechanism alone cannot clamp the tool holder during processing. Therefore, it is necessary to use a drawbar for clamping and unclamping within the main shaft of the tool holder, which complicates the structure of the main shaft and reduces the rigidity of the main shaft.

In other words, the drawbar must be installed so as to pass through the main shaft, and a disc spring that urges the drawbar in the clamping direction is installed on the outer periphery of the drawbar. A cylinder must be provided that operates in the unclamping direction against the spring, and the rear end of the spindle must be connected to the spindle drive motor, making the structure at the rear of the spindle extremely complicated. Also, manufacturing and assembly are not easy. In addition, it is necessary to provide the main shaft with a center hole for mounting the drawbar and disc spring, and to form a slit in the main shaft that passes through the member connecting the cylinder and the drawbar, which reduces the rigidity of the main shaft. be. Further, even when the cutting tool oil is supplied through the main shaft, there are problems such as the formation of the oil supply hole being complicated.

The present invention was proposed in view of the above-mentioned problems of the conventional technology, and its purpose is to simplify the structure of the spindle and improve the rigidity of the spindle while maintaining the function of shortening tool change time. The aim is to provide equipment.

Means for Solving the Problems In order to achieve the above object, the spindle device of the present invention has a taper hole and a pull stud accommodation hole at the tip for receiving the taper shank part and the pull stud part of the tool holder, and a pull stud accommodation hole. A main shaft having radial through holes at multiple locations around the main shaft, a locking member of the pull stud section accommodated in each radial through hole, and a locking member of the pull stud part accommodated in each radial through hole, and a part of the inner periphery is provided on the outer periphery of the tip of the main shaft so as to be slidable in the axial direction. A self-locking position in which the lock members are pushed inward in the radial direction and held therein, and an elastic engagement member on a part of the inner periphery separated in the axial direction from this position to allow each lock member to retract radially outward through an elastic engagement member. The control sleeve has a mating position and is always held in a self-locking position by a spring, and a sleeve moving member that moves the control sleeve to the resiliently engaged position against the spring during automatic tool exchange. It is characterized by:

Operation When the spindle is moved to the tool exchange position and the sleeve moving means moves the control sleeve to the elastic engagement position, the locking member can be retracted radially outward, and the exchange arm moves the tool holder. It is possible to grasp it and pull it out from the main shaft.

When installing the next tool on the spindle, the locking member is in the elastic engagement position of the control sleeve, and when the exchange arm installs the tool holder on the spindle, it elastically engages with the pull stud part of the tool holder and temporarily holds it. . Therefore, even if the exchange arm releases its grip on the tool holder, the tool holder will not fall off. When the control sleeve is moved to the self-locking position under the action of the spring, the locking member cannot be retracted radially outwardly and firmly holds the pull stud portion of the tool holder on the main shaft. Therefore, this is sufficient for clamping during processing.

The sleeve moving member only needs to move the main shaft and the control sleeve relative to each other in the axial direction, and when the main shaft moves to the tool exchange position, the sleeve moving member is moved to correspond with the control sleeve just before the end of the path. If it is fixedly installed, there is no need for a special drive source, and the control sleeve can be moved to the elastic engagement position using the action of moving the spindle to the tool exchange position. Therefore, there is no need to provide a disc spring for clamping the tool holder, a cylinder for unclamping, a draw bar, etc. on the main shaft side.

Embodiment FIG. 1 is a vertical and horizontal side view of the tip of the spindle showing an embodiment of the device of the present invention, and FIG. 2 is a cross-sectional view taken along the line -- in FIG. The tool holder, 4 is a locking member, 5 is a control sleeve, 6 is an elastic engagement member, 7 is a spring, and 8 is a sleeve moving member.

The spindle 2 is connected to the spindle head 1 via a spindle bearing 9.
It is rotatably supported through the inside of the shaft, and is connected to the main shaft drive section at the rear end [not shown], so there is no need to provide a disc spring, drawbar, clamp cylinder, etc. However, there is no need to provide a cutting oil supply hole. ,
It is provided to penetrate in the axial direction.

The main shaft 2 has a taper hole 2a and a pull stud accommodating hole 2b at its tip for receiving the taper shank portion 3a and pull stud portion 3b of the tool holder 3, and has radial penetrations at multiple locations around the pull stud accommodating hole 2b. A hole 2c is provided.

The tool holder 3 has a grip groove 3c that is gripped by an exchange arm (not shown) of an automatic tool changer, and an engagement groove 3d that engages with a detent protrusion 2d on the tip surface of the main shaft 2. [not shown] is fixed.

The locking member 4 has a radial through hole 2c in the main shaft 2.
The case is shown in which a plurality of steel balls are used, but this means that only one steel ball can engage the pull stud portion 3b of the tool holder 3, considering the thickness of the spindle 2. This is to prevent the rigidity of the main shaft 2 from deteriorating since this requires the use of large-diameter steel balls.Therefore, in addition to the steel balls, the locking member 4 must have semispherical ends at both ends. It may also be a rod-shaped rod pin.

The control sleeve 5 is arranged in the direction of the key 10 and in the keyway 11.
It is attached to the outer periphery of the tip of the main shaft 2 so as to be able to slide freely in the axial direction and to rotate integrally, and to a self-locking position where the locking member 4 is pushed radially inward and held at a part of the inner periphery, and from this position in the axial direction. Each locking member 4 is connected via an elastic engagement member 6 to a portion of the inner circumference separated from each other.
It has an elastic engagement position that allows it to be retracted radially outward, and is always held in a self-locking position by a spring 7.

The control sleeve 5 integrally has a large-diameter flange 5a protruding from the outer periphery, and the sleeve moving member 8 moves along the movement path of the main spindle 2 to the automatic tool changing position in correspondence with the large-diameter flange 5a. It is fixedly installed just before the end of the

The sleeve moving member 8 has a shaft 8 attached to the bracket 8a.
This figure shows a case in which the roller 8c is rotatably attached via the main shaft 2, and is designed to reduce wear when it comes into contact with the large diameter flange 5a of the control sleeve 5 moving while rotating together with the main shaft 2. However, it may also be a simple fixed stopper.

In FIG. 1, the spring 7 is compressed and interposed between a spring receiver 12 fixed to the outer periphery of the tip of the main shaft 2 and the large-diameter flange 5a of the control sleeve 5, and is inserted into the large-diameter flange 5a. It is covered with a fixed spring cover 13.

The elastic engagement member 6 is slidably fitted into a radial hole 5c of a base sleeve 5b that is integrated with the control sleeve 5, and is constantly urged radially inward by a spring 5d. A locking collar 6a is provided at the radially outer end of the elastic engagement member 6, and a locking collar 6a is provided in the radial hole 5 of the base sleeve 5b correspondingly.
A large-diameter locking step portion 5e is formed on the radially outward side of c, thereby allowing the elastic engagement member 6 to
The radially inner end surface is substantially aligned with the inner diameter surface of the control sleeve 5. A cover sleeve 5f is integrally fixed to the outer peripheral surface of the base sleeve 5b, thereby making it possible to incorporate the elastic engagement member 6 and the spring 5d into the base sleeve 5b.

In FIG. 1, a holding cylinder 14 for holding the steel ball at the radially inner end of the locking member 4 in a normal position is screwed to the pull stud housing hole 2b of the main shaft 2. 14 anti-rotation pins 15 are provided on the main shaft 2, and these retaining cylinders 14
may be omitted.

The embodiment of the present invention has the following configuration, and the operation will be explained next.

FIG. 1 shows a state in which the control sleeve 5 has been slightly moved by the sleeve moving member 8 against the spring 7 from the self-locking position to the elastic engagement position; in this state, the locking member 4 is , is held in a radially inwardly pushed position by the inner peripheral surface of the control sleeve 5, and is in a state almost the same as a self-locked state. In this state, the pull stud portion 3b of the tool holder 3 is locked by the locking member 4, and is prevented from coming off from the main shaft 2.

In the above state, if the main shaft 2 is moved to the left in FIG. It becomes possible to move radially outward against the

Therefore, the tool holder 3 is moved against the main shaft 2 and the first
When moved to the right in the figure, the locking member 4 retracts and the tool holder 3 can be pulled out from the spindle 2.

It is also possible to attach the next tool holder to the spindle in the same way. When the installation is completed, move the main shaft 2 to the right in Fig. 1, and the spring 7
This moves the control sleeve 5 to the self-locking position, holds the locking member 4 in the radially inwardly pushed position, and pulls the pull rod 3b of the tool holder 3.
is locked within the main shaft 2.

If the sleeve moving member 8 is fixedly installed just before the end of the movement path of the main spindle 2 to the automatic tool change position,
When the main spindle 2 moves to the tool exchange position, the large diameter flange 5a of the control sleeve 5 comes into contact with the sleeve moving member 8 waiting just before the end of the movement path, and the main spindle 2 resists the spring 7. Then, the control sleeve 5 moves to the elastic engagement position. The locking member 4 and the elastic engagement member 6 stop at corresponding positions, and this position becomes the automatic tool changing position of the main spindle 2. That is, during the movement of the spindle 2 to the automatic tool change position, the control sleeve 5 can be moved into the resiliently engaged position and can be unlocked. When the spindle 2 reaches the automatic tool change position, the change arm is actuated to grip the tool holder 3, which can then be immediately pulled out from the spindle 2. After this, the exchange arm stores the tool in the tool storage position of the tool magazine, and the next tool is taken out from the tool magazine and mounted on the spindle 2 by the exchange arm. Then, the main spindle 2 moves toward the workpiece machining position, and as a result, the large diameter flange 5a of the control sleeve 5
is separated from the sleeve moving member 8,
The control sleeve 5 is moved into a self-locking position by the spring 7 and locks the locking member 4. Therefore, the tool holder 3 can be held securely during machining.

Effects of the invention According to the invention, disc springs, drawbars, unclamp cylinders, etc. can be eliminated, the structure of the spindle can be simplified and rigidity improved, and tool change time can be shortened. It is useful as such.

[Brief explanation of drawings]

FIG. 1 is a vertical and horizontal side view of the tip of the main shaft showing an embodiment of the device of the present invention, and FIG. 2 is a sectional view taken along the line -- in FIG. 1. DESCRIPTION OF SYMBOLS 1...Spindle head, 2...Spindle, 3...Tool holder, 4...Lock member, 5...Control sleeve, 6
. . . elastic engagement member, 7 . . . spring, 8 . . . spring moving member.

Claims (1)

[Claims for Utility Model Registration] A main shaft having a taper hole and a pull stud accommodation hole at the tip for receiving the taper shank part and pull stud part of a tool holder, and radial through holes at multiple locations around the pull stud accommodation hole. A locking member of the pull stud portion accommodated in each radial through hole, and a self-locking device that is slidably slidable in the axial direction on the outer periphery of the tip of the main shaft and that pushes and holds the locking member radially inward on a part of the inner periphery. and an elastic engagement position on a part of the inner periphery axially spaced apart from this position, which allows each locking member to retract radially outward via an elastic engagement member, and is always kept in a self-locking position by a spring. A spindle device comprising: a control sleeve that is held; and a sleeve moving member that moves the control sleeve to an elastic engagement position against the spring during automatic tool exchange.