JP3818695B2 - Spindle device - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a spindle device on which a cutting tool is detachably mounted.
[0002]
[Prior art]
For example, Japanese Patent Application No. 7-16376 discloses a spindle device in which a cutting tool in a conventional technique is detachably mounted.
The spindle device is integrated with the shank gripping part for gripping / releasing the taper shank of the cutting tool that is detachably fitted in the tapered hole formed at the tip of the spindle, and the spindle is integral in the rotational direction, and the axial direction Are slidably fitted, a shank gripping member actuating member that opens and closes the shank gripping part by moving back and forth in the axial direction, an annular nut member that is rotatably and concentrically fitted to the main shaft, and an outer peripheral surface of the annular nut member A clamping piston, which is provided on the main shaft housing so as to be freely disengaged from the locking recess, and which is fastened to be non-rotatable by engagement, or which is freed by disengagement, and an annular nut member. A tool clamp operating piece coupled with the shank gripping portion operating portion is provided while the outer periphery is screwed.
[0003]
In the above-described conventional spindle device, when the tool is mounted by exchanging the cutting tool with respect to the spindle stopped at the predetermined rotation original position, the clamping piston is attached to the outer peripheral surface of the annular nut member. After engaging the locking recess to make the annular nut member non-rotatable, the tool clamp operating piece screwed with the non-rotatable annular nut member is rotated by rotating the main shaft at a low speed.
[0004]
Then, the tool clamp operating piece is displaced in the axial direction, whereby the shank gripping part operating member is also displaced together with the tool clamp operating piece. As a result, the shank gripping part is closed and grips the taper shank of the cutting tool. At that time, in a state where the taper shank of the cutting tool is properly gripped, the rotation of the spindle reaches a predetermined torque. Then, the clamping piston is detached from the engaging recess on the outer peripheral surface of the annular nut member, and the annular nut member is rotated together with the main shaft, and then the processing is performed by the rotation of the main shaft.
[0005]
Normally, the spindle drive device has a function for stopping a predetermined rotation original position of the spindle, that is, an orientation function, but the angle phase of the spindle rotated until a predetermined torque for proper gripping is reached. The function of confirming is not provided.
Therefore, as shown in FIG. 14, the spindle device includes a deceleration proximity switch 21, a fixed position confirmation proximity switch 19, and an annular nut member 17 that are provided in the spindle housing and detect the rotational angle phase of the annular nut member 17. A first target 22 corresponding to a proximity switch for deceleration provided on an outer peripheral surface and a second target 20 corresponding to a proximity switch 19 for confirming a fixed position are provided.
[0006]
In the phase relationship in which the second target 20 faces the fixed position confirmation proximity switch 19, the clamping piston 18 is engaged with the engaging recess 17 a on the outer peripheral surface of the annular nut member 17, and the first target 22 is decelerated. When facing the proximity switch 21 for use, the main shaft 4 is stopped and rotated at a low speed.
[0007]
When the cutting tool is removed from the main spindle stopped at the predetermined rotation position in the cutting tool replacement after the machining is completed, the main spindle 4 is compensated so as to compensate for the low-speed rotation until the predetermined torque is reached in the cutting tool gripping. Unless it is rotated, the clamping piston 18 cannot engage with the locking recess 17 a on the outer peripheral surface of the annular nut member 17.
However, the rotation angle of the main shaft is not constant until a predetermined torque for completion of fastening is reached due to the shape and size of the taper shank of the cutting tool and the size of the shank gripping portion.
[0008]
Accordingly, the mounting / tightening / releasing of the cutting tool with respect to the spindle when the tool is replaced in the above-described conventional spindle apparatus will be described with reference to FIGS.
For the sake of convenience, after describing the mounting and fastening of a new cutting tool to be used in the next process to the main spindle 4 following the release of the used cutting tool from the main spindle 4 in the tool change, the main spindle 4 of the cutting tool will be described. I will explain the release from the mounting.
[0009]
As shown in FIG. 14 (a), after the machining process with one cutting tool is completed, the tool holder of the used cutting tool is removed from the main shaft 4 by exchanging the tool, and the tool holder of the new cutting tool is removed. At the time of mounting and tightening, the main shaft 4 is rotationally positioned at the rotation original position, and the annular nut member 17 is fixed to the main shaft housing 1 so as not to rotate by the clamping piston 18 that protrudes and press-engages with the locking recess 17a. It is in the state that was done. The shank gripping part is in the tool mounting release state.
[0010]
Then, after the used cutting tool is removed from the spindle 4 by the tool changing arm, a shank of the cutting tool is inserted into the spindle 4 so that the new cutting tool is mounted on the spindle 4 of the machining center.
Tool mounting and fastening will be described in accordance with the process in FIG.
Step 1
A tool mounting fastening command is output.
[0011]
Step 2
Then, the main shaft is driven to rotate at high speed.
Although the main shaft rotates counterclockwise at high speed, the annular nut member 17 is prevented from rotating by the clamping piston 18, so that the tool clamp operating piece is retracted, and the tool clamp operating piece is retracted so that the shank gripping portion is cut. Tighten the tool shank.
Step 3
As described above, the counterclockwise jogging high-speed rotation of only the spindle 4 proceeds, the mounting and clamping progress, the tool clamp operating piece is prevented from moving backward at the rotation angle θ, and the shank of the cutting tool shank on the spindle 4 is completed. To do. (See FIG. 14 (b))
[0012]
Step 4
When the mounting and fastening of the shank of the cutting tool is completed, the clamping piston 18 is detached from the locking recess 17a of the annular nut member 17.
Therefore, since the annular nut member 17 is rotatable together with the main shaft 4, there is nothing that prevents the main shaft 4 from rotating, and the main shaft 4 can be driven to rotate. (See FIG. 14 (c))
Step 5
Thus, the new cutting tool mounted and fastened to the main shaft 4 that is rotationally driven performs a desired cutting process on the workpiece.
[0013]
Next, the mounting / release of the cutting tool at the time of changing the tool will be described.
In the above, the machining process with the cutting tool mounted and fixed to the main shaft 4 is finished, and the main shaft 4 is stopped at a predetermined rotation original position (see FIG. 14D), and the tool exchange with the next cutting tool is performed. When done, the tool is released.
[0014]
The tool mounting release will be described according to the process in FIG.
Step 6
Tool mounting release command is output.
In order to release and attach the cutting tool, the locking recess 17a of the annular nut member 17 must be opposed to the clamping piston 18 in order to fix the annular nut member 17. However, since the main shaft 4 is positioned and stopped at a predetermined rotation original position, the locking concave portion 17a of the annular nut member 17 has a rotation angle θ (when the main shaft 4 rotates counterclockwise for the previous tool mounting fastening. Only the position of the clamping piston 18 is displaced from the position shown in FIG. (See FIG. 14 (d))
[0015]
Step 7
The main shaft 4 is driven to rotate in a clockwise direction at high speed. Then, the annular nut member 17 locked to the main shaft 4 is integrally rotated at a high speed in the clockwise direction. (See FIG. 14 (d))
Step 8
When the first target 22 faces the deceleration proximity switch 21, the position of the first target 22 is detected by the deceleration proximity switch 21.
[0016]
Step 9
When the first target 22 is detected by the deceleration proximity switch 21, the high-speed inching rotation of the main shaft 4 is stopped so that the locking recess 17 a of the annular nut member 17 faces the position of the clamping piston 18. (See FIG. 14 (e))
However, because the spindle 4 overruns and stops due to high-speed inching rotation, the locking recess 17a of the annular nut member 17 is shifted from the position of the clamping piston 18. (See FIG. 14 (f))
[0017]
Step 10
When the overrun is stopped from the rotation original position of the main shaft 4, the range of the first target 22 faces the decelerating proximity switch 21, so that the main shaft 4 is driven in a low-speed jogging rotation counterclockwise.
Step 11
When the second target 20 faces the fixed position confirmation proximity switch 19, the position of the second target 20 is detected by the fixed position confirmation proximity switch 19.
[0018]
Step 12
When the second target 20 is detected by the home position confirmation proximity switch 19, the locking recess 17 a of the annular nut member 17 faces the position of the clamping piston 18, and the low speed inching rotation of the main shaft 4 is stopped. Due to the low-speed jogging rotation, the spindle 4 accurately stops at the rotation original position. In this state, the locking recess 17 a of the annular nut member 17 faces the clamping piston 18. (See FIG. 14 (g))
Then, the clamping piston 18 protrudes and engages with the locking recess 17a.
[0019]
Step 13
Due to the pressing engagement of the clamping piston 18 with respect to the locking recess 17a, the main shaft 4 rotates clockwise and is returned to the original rotation position in a state where the annular nut member 17 cannot rotate. (See Fig. 14 (a))
This state is the initial state of the tool change described above, in which the main shaft 4 is at the rotation original position, and the shank gripping portion is in the tool mounting / release state. The annular nut member 17 is fixed to the main shaft housing 1 so as not to rotate by a clamping piston 18 that protrudes and press-engages with the locking recess 17a. That is, the tool can be exchanged with the next cutting tool.
Step 14
As with the previous time, the tool is replaced with the next cutting tool.
[0020]
[Problems to be solved by the invention]
When machining with the held cutting tool is completed as described above, and the used cutting tool is removed in the replacement with the next cutting tool, the clamping piston has an annular shape around the main shaft stopped at the predetermined rotation original position. In order to prevent erroneous detection of the proximity switch at the stop due to the detection of the proximity switch, a proximity switch for detecting the position is provided at the time of rotational positioning until it can be engaged with the locking recess on the outer peripheral surface of the nut member. If the jogging rotation is performed at a low speed, the operation time becomes long and it is inefficient.
[0021]
Therefore, in the spindle device of the above-mentioned conventional technology, not only the above-mentioned inching rotation is performed at a low speed but also a high-speed inching rotation and a low-speed inching rotation by two-step detection by a proximity switch for deceleration and a proximity switch for confirming a fixed position. It is divided into two.
The operation will be described with reference to FIG. 15. The main shaft is stopped at a predetermined rotation original position (T ₀ ), The locking recess 17a of the annular nut member 17 faces the position of the clamping piston 18, and the first target 22 is detected by the deceleration proximity switch 21 by the deceleration proximity switch. Time (T ₁ ), The high-speed inching rotation drive of the main shaft 4 is stopped.
[0022]
However, due to the high-speed inching rotation, the spindle 4 overruns and the time (T ₂ ) And is driven in a reverse direction at a low speed inching rotation (speed VL), the locking recess 17a of the annular nut member 17 is opposed to the position of the clamping piston 18, and the second target 20 is close to the fixed position confirmation. When detected by the switch 19 (T _Three ) Is stopped, and the main shaft 4 stops at a position where the locking recess 17a of the annular nut member 17 faces the position of the clamping piston 18 due to the low speed inching rotation.
[0023]
The rotation angle of the overrun (the hatched triangle area in FIG. 15) is equal to the rotation angle of the low-speed inversion reverse rotation (the hatched trapezoid area in FIG. 15). T ₀ To T ₁ If the speed of the high-speed inching rotation is increased in order to shorten the time until the rotation time, the overrun rotation angle (triangle area in FIG. 15) increases, and the rotation angle of the low-speed inversion reverse rotation (shaded trapezoid area in FIG. 15) also increases. Increase. As a result, T ₂ To T _Three The time until is increased. In addition, since the main shaft 4 stops at the position where the locking recess 17a of the annular nut member 17 is opposed to the position of the clamping piston 18, the speed of the low speed inching reverse rotation cannot be increased.
[0024]
Therefore, the time for indexing and rotating the main shaft from a predetermined rotation original position to the position where the locking recess 17a of the annular nut member 17 faces the position of the clamping piston 18, that is, T ₀ To T _Three It is difficult to shorten the time until the time.
Further, providing the spindle driving device itself with a function of recognizing the spindle rotation angle phase has a disadvantage that the apparatus is expensive.
The present invention provides a spindle apparatus having a function of efficiently rotating and positioning a spindle at a desired stop position other than a predetermined rotation original position without having an expensive function of recognizing a spindle rotation angle phase. It is aimed.
[0025]
[Means for Solving the Problems]
The spindle device of the present invention includes a spindle that is rotatably supported; a spindle motor that rotationally drives the spindle; a shank gripping portion that is provided on the spindle and fastens and releases a tool shank; and is axially displaceable to the spindle. A shank gripping member actuating member provided to open and close the shank gripping portion by its displacement; an annular nut member provided concentrically rotatably with respect to the main shaft and having an internal thread portion formed on an inner periphery; opening and closing of the shank gripping portion An annular nut member fastening means for fastening the annular nut member in a non-rotatable manner during operation; it is screwed into a female screw portion of the annular nut member provided integrally with the main shaft in the rotational direction and freely movable back and forth in the axial direction; A tool clamp piece coupled to the shank gripping member actuating member; a rotating member driven to rotate separately from the main shaft; and a control device for controlling the rotational driving of the main shaft motor and the rotating member It is constructed from.
[0026]
Then, the control device determines the completion of shank clamping by the shank gripping portion in the rotational driving of the main shaft; synchronous rotation for driving the rotating member only on a control signal in synchronization with the rotation of the main shaft Control means; at the time of shank clamping, the rotation angle at which the spindle rotates from the rotation original position of the spindle in the shank released state to the shank clamping completion position when the annular nut member fastening means cannot rotate the annular nut member. A calculating means for calculating from a synchronous rotation control signal of the rotating member that rotates synchronously; and a function of a storage means for storing a shank release start position in which the rotation angle calculated by the calculating means is added to a rotation original position of the spindle. When the shank is released, the main shaft in the shank-tightened state is driven to rotate from the original rotation position to the shank release start position. In release starting position, in terms of the annular nut member by an annular nut member fastening means is nonrotatably state, is adapted to operate controlled to rotate the main shaft rotational situ.
[0027]
Further, another type of spindle device further includes a detector for detecting the shank release start position, and the control device starts the shank release from the rotation original position of the spindle in a shank-tightened state when the shank is released. The rotary nut is rotated to the position offset from the position, and further rotated by the detector until the shank release start position is detected by the detector. At the shank release start position, the annular nut member cannot be rotated by the annular nut member fastening means. In this state, the operation is controlled so as to rotate the main shaft to the rotation original position.
[0028]
When describing the mounting and tightening of the tool at the time of tool change in the spindle device, the spindle device is in the initial state where the spindle is stopped at the rotation original position when the old and new tools are exchanged. That is, the tool clamp operating piece is in the release position. Therefore, the shank gripping part is in a released state. The annular nut member is in a position where it can engage with the annular nut fastening means, and is fastened non-rotatably by the annular nut fastening means.
When a new tool is mounted on the spindle, the tool shank is inserted into the spindle.
[0029]
Therefore, when the main shaft is rotated, the tool clamp operating piece rotating together with the main shaft is directed to the locking position in the axial direction with respect to the main shaft with respect to the annular nut member whose rotation is prevented by the annular nut member fastening means. Displace to The shank gripping part fastens the shank by the displacement of the tool clamp operating piece, that is, the shank gripping part operating member.
When it is determined that the shank has been clamped due to the displacement of the tool clamp operating piece, the spindle is stopped.
Thus, the tool is mounted on the spindle.
[0030]
In the control device, the rotation angle of the main shaft during this period is calculated from the synchronous rotation control signal of the rotating member that is driven to rotate synchronously with the main shaft only on the control signal, and the calculated rotation angle is added to the rotation position of the main shaft. The shank release start position is stored.
The rotation angle of the main shaft from the rotation original position required for the tool mounting and fastening required as described above is not constant depending on the shape and size of the taper shank of the cutting tool, the size of the shank gripping portion, and the like.
[0031]
Then, the annular nut fastening means releases the annular nut member, and the annular nut member becomes rotatable together with the main shaft.
Thus, the spindle is driven to rotate, and a desired machining is performed on the workpiece by the tool.
[0032]
Next, the tool mounting / release at the time of tool change in the spindle device will be described. As described above, the machining process with the tool fixed to the spindle is finished, and the spindle is positioned and stopped at a predetermined rotation original position. The
In order to release the tool, the annular nut member must be positioned at a position where the annular nut member can be engaged with the annular nut member fastening means so that the annular nut member is fastened by the annular nut member fastening means and cannot be rotated. . That is, the main shaft coupled with the annular nut member must be positioned at the shank release start position.
[0033]
Therefore, when the tool mounting release command is output in the control device, the shank release start position stored in the storage means for storing the shank release start position at the time of the tool mounting and fastening described above is called, and the rotation original position is set. A certain spindle is rotationally driven by a rotation angle corresponding to its position in accordance with a control command from the control device. As a result, the annular nut member that rotates integrally with the main shaft is positioned at a position where it can engage with the annular nut member fastening means.
[0034]
Then, the annular nut member is fastened by the annular nut member fastening means to be in a non-rotatable state, and the main shaft is rotationally driven to be rotationally positioned at a predetermined rotation original position and stopped.
When the main shaft is rotated until it reaches the rotation home position, the annular nut member is prevented from rotating by the annular nut member fastening means. Displacement in the axial direction towards the release position. The shank gripping part releases the shank by the displacement of the tool clamp operating piece, that is, the shank gripping part operating member. Thus, the tool can be removed from the spindle.
[0035]
When the tool release in the spindle device in the case of the type that also includes the detector for detecting the shank release start position is described, the machining by the tool fixed to the spindle as described above is performed. The process is completed, and the spindle is stopped at a predetermined rotation original position.
[0036]
In order to release the tool, the annular nut member must be positioned at a position where it can be engaged with the annular nut member fastening means so that the annular nut member is fastened by the annular nut member fastening means and becomes non-rotatable. That is, the main shaft coupled with the annular nut member must be positioned at the shank release start position.
[0037]
Therefore, when the tool mounting release command is output in the control device, the shank release start position stored in the storage means for storing the shank release start position at the time of the tool mounting and fastening described above is called, and the rotation original position is set. A certain spindle is rotationally driven by a rotation angle corresponding to a position offset from the shank release start position by a control command from the control device. Then, the main shaft is pivoted until the shank release start position is detected by the detector. As a result, the annular nut member coupled to the main shaft is brought into a position where it can engage with the annular nut member fastening means. Positioned. Then, after the annular nut member is fastened by the annular nut member fastening means to be in a non-rotatable state, the main shaft is rotationally driven, rotationally positioned at a predetermined rotation original position, and stopped.
[0038]
When the main shaft is rotated until it reaches the rotation home position, the annular nut member is prevented from rotating by the annular nut member fastening means. It is displaced in the axial direction toward the release position, and the shank gripping part releases the shank by the displacement of the tool clamp operating piece, that is, the shank gripping part operating member. Thus, the tool can be removed from the spindle.
[0039]
DETAILED DESCRIPTION OF THE INVENTION
A spindle device according to an embodiment of the present invention will be described with reference to the drawings.
As shown in FIG. 1, a built-in spindle motor 3 controlled by a control device is provided in an intermediate portion of a spindle 4 rotatably supported by a rolling bearing 2 in the spindle housing 1, and a tip of the spindle 4 is provided at the tip of the spindle 4. A tool holder 41 for holding the cutting tool 40 is mounted.
[0040]
In the tool holder 41, the cutting tool 40 can be displaced in the radial direction through the cutting tool displacement mechanism due to the axial displacement of the U-axis operating rod 42. As the cutting tool displacement mechanism, there are various mechanisms such as a cam mechanism and a wedge mechanism, and the cam groove mechanism 43 is illustrated as an embodiment.
A through-hole 6 is formed in the center of the main shaft 4, and a U-axis tension rod 7 for displacing a cutting tool that is detachably engageable with a U-axis operating rod 42 of the tool holder 41 is fitted in the through-hole 6. Yes.
[0041]
The rear end portion of the U-axis tension rod 7 for displacing the cutting tool, which is inserted in the through hole 6 so as to be slidable in the axial direction and restricted in rotation with respect to the main shaft 4, protrudes from the main shaft 4, Are coupled to the ball screw 32 via a coupling 31 coupled in the axial direction without rotation. A U-axis servomotor 33 controlled by the control device 30 is mounted on the rear end portion of the spindle housing 1, and a ball screw nut 34 into which a ball screw 32 is screwed onto the front end of the output shaft of the U-axis servomotor 33. However, encoders 35 are respectively attached to the rear ends.
The spindle housing 1 is provided with a rotation speed sensor 36 that detects the rotation of the spindle housing 1 facing the rear end of the spindle 4.
[0042]
A spindle drive amplifier 37 and a U-axis drive amplifier 38 are connected to the control device 30 so that a control command from the control device 30 is input, and detection signals are input from the encoder 35 and the rotation speed sensor 36. The encoder 35 and the rotation speed sensor 36 are connected to the above. The spindle drive amplifier 37 and the U-axis drive amplifier 38 are connected to control and drive the built-in spindle motor 3 and the U-axis servomotor 33 in accordance with a control command from the control device 30.
[0043]
In the illustrated embodiment, only the rotational speed sensor 36 inputs a detection signal to the control device 30, but a clamp torque detection means (not shown) is provided on the main shaft 4, and the detection signal from the clamp torque detection means is received. Similarly, the input may be performed, or the rotational speed sensor 36 may be omitted and only the clamp torque detecting means may be used.
[0044]
The control device 30 includes a CPU, a ROM, a RAM, an interface, an input board, a display and the like like a normal NC control device, and has a normal control function of a machining center as a control system. As shown, the synchronous control command means 51, the spindle rotation command means 52, the U-axis feed command means 53, the all-axis machine lock command means 54, the gate circuit 55, the current position of the U-axis in the fastening and release of the tool holder 41 in the spindle 4 The storage unit 56, U-axis coordinate counting unit 57, clamp determination unit 58, U-axis skip position storage unit 59, spindle rotation amount calculation unit 60, and rotation locking position storage unit 61 are provided.
[0045]
When all-axis machine lock is performed by a command from the all-axis machine lock command means 54, the spindle 4 is driven to rotate synchronously by a command from the synchronization control command means 51. The member is a ball screw nut 34 that displaces the U-axis tension rod 7. Not only the (U-axis servomotor 33), but other rotational drive shafts in the machining center (Drive motor) An encoder may be provided to the rotary drive shaft.
[0046]
The main shaft 4 will be described in detail with reference to FIGS. 2, 3, and 4. The main shaft 4 has a tapered hole 5 in which the outer peripheral tapered surface of the taper shank 41 a of the tool holder 41 is fitted at the tip thereof. Is penetrated from the bottom of the taper hole 5 toward the rear end.
The distal end portion of the U-axis tension rod 7 is reduced in diameter in two steps, forming a first small diameter portion 7a and a second small diameter portion 7b beyond the first small diameter portion 7a. The U-axis tension rod 7 is provided with a tension sleeve 8 concentrically with the tip portion.
[0047]
In the collar 9 in which the axial long hole 9a is formed in the rear end portion so as to face the diameter direction, the inner peripheral surface of the large-diameter portion 9b is connected to the first small-diameter portion 7a of the U-axis tension rod 7 and the large-diameter portion 9b. The outer peripheral surface is fitted to the tension sleeve 8 and the inner peripheral surface of the small diameter portion 9c is fitted to the second small diameter portion 7b so as to be slidable in the axial direction. The compression coil spring 10 wound around the first small-diameter portion 7a of the U-axis tension bar 7 is fitted between the fixed base of the tension sleeve 8 and the rear end surface of the collar 9, and the U-axis tension bar 7 is engaged with the elongated hole 9a of the collar 9 in a diametrical direction. Therefore, the collar 9 can move forward and backward with respect to the U-axis tension rod 7 within the range of the long hole 9 a and is always urged forward by the compression coil spring 10.
[0048]
A tip member 12 that holds a collet 13 that holds the U-axis actuating rod 42 of the tool holder 41 is provided at the tip of the U-axis tension rod 7, that is, the second small-diameter portion 7b. It is fixed.
The tip of the small diameter portion 9c of the collar 9 protrudes from the tip of the tip member 12, and the inner peripheral surface thereof is a tapered surface 9d.
[0049]
And the inner peripheral protrusion of the base part fits between the front flange part and the rear collar part of the tip member 12, and the collet 13 attached to the tip member 12 so as to be able to move is the taper surface of the collar 9 on the outer peripheral taper surface. A collet that is in contact with 9d and grips a pull stud 42a formed at the rear end portion of the U-axis operating rod 42 of the tool holder 41 from the tip member 12, the tapered surface 9d of the collar 9 and the collet 13. A chuck is configured.
[0050]
A clamp ball operating sleeve 14 is fitted into the small diameter portion 9c of the collar 9 so as to be slidable in the axial direction. That is, the center hole 14a in the front half and the center hole 14b in the rear half pass through the clamp ball operating sleeve 14, and the U-axis operating rod 42 of the tool holder 41 is inserted into the center hole 14a. The center hole 14 b is fitted into the small diameter portion 9 c of the collar 9.
[0051]
A clamp ball operating recess 14d having a front edge slope 14c is formed on the outer peripheral surface of the front half of the clamp ball operating sleeve 14, and the tool clamp operating piece 15 and the U-axis operating rod are formed on the outer peripheral surface of the rear half. The clamp piece 16 is fitted back and forth, and the former is engaged with an engagement protrusion 14e formed on the clamp ball operating sleeve 14 to restrain the axial displacement with respect to the clamp ball operating sleeve 14, and the latter is The clamp ball actuating sleeve 14 can be displaced in the axial direction, but the rear end portion can be opposed to and separated from the front end step portion of the large-diameter portion 9 b of the collar 9.
[0052]
An annular nut member 17 having an outer diameter substantially equal to the outer diameter of the main shaft 4 is rotatably fitted in an annular groove 4a formed on the outer peripheral surface of the main shaft 4 in the axial direction range corresponding to the rear half of the clamp ball operating sleeve 14. The annular nut member 17 is engraved with a first screw portion 17a in the first half and a second screw portion 17b in the second half of each other. The main shaft housing 1 is provided with a clamping piston 18 in a radial direction so as to face the outer peripheral surface of the annular nut member 17.
[0053]
Then, between the bottom surface of the annular groove 4a and the outer peripheral surface of the through hole 6 of the main shaft 4, as shown in FIG. 4, radial cavities 24 penetrate at intervals of 120 degrees, and the tool clamp operating piece 15 and the U-axis operation The radial screw portions 15a, 16a of the bar clamp piece 16 project into the radial cavities 24, 24, 24, and the rotation of the tool clamp operation piece 15 and the U-axis operation bar clamp piece 16 is restricted, and the screw portion 15a is Annular nut member 17 The threaded part 16a is screwed to the first threaded part 17a of the nut member 17 and the second threaded part 17b of the annular nut member 17, respectively.
[0054]
The spindle 4 is formed with a concentric clamp ball holding sleeve portion 25 that forms the tip of the through hole 6 within the tapered hole 5 at the tip. As a result, the outer peripheral surface of the clamp ball holding sleeve portion 25 and the tapered hole 5 A cylindrical tapered shank 41a of the tool holder 41 is fitted into a tapered annular hole formed by the inner peripheral surface. In the clamp ball holding sleeve portion 25, a clamp ball hole 25a corresponding to the clamp ball hole 41d of the taper shank 41a of the tool holder 41 fitted in the taper annular hole penetrates in the radial direction.
[0055]
Clamp ball A clamp ball 27 is accommodated across the clamp ball operating recess 14 d of the operating sleeve 14 and the clamp ball hole 25 a of the clamp ball holding sleeve portion 25.
[0056]
The tool holder 41 attached to the main shaft 4 is formed by extending a cylindrical taper shank 41a having a hollow hole 41b opened at the rear end.
The taper shank 41a is provided with a clamp ball hole 41d having a peripheral edge slope, and the stepped portion of the base of the taper shank 41a is formed on the tip surface of the main shaft 4 when the tool holder 41 is mounted on the main shaft 4. Abut.
[0057]
Therefore, the tool holder 41 is driven by the contact of the outer peripheral tapered surface of the taper shank 41a with the tapered hole 5 of the main shaft 4 and the contact of the stepped portion of the base of the taper shank 41a with the front end surface of the main shaft 4, that is, by the two-surface constraint. 4 is attached.
Here, in the embodiment of the invention described above, the tool holder 41 is defined as a standard shape that is generally popular in the market, as described above, in which the shape of the two-surface constraining portion in the fastening of the spindle 4 and the tool holder 41 is fixed. Simplification of production and management.
On the outer peripheral surface of the tool holder 41, an annular groove 41c that engages with an exchange hand of the automatic tool changer is formed.
[0058]
Although it can be omitted in the first embodiment, in the second embodiment, as shown in FIG. 4, the spindle housing 1 has a fixed position at a position shifted in phase from the clamping piston 18. A confirmation proximity switch 19 is provided in the radial direction facing the outer peripheral surface of the annular nut member 17. In the illustrated example, the clamping piston 18 and the fixed position confirmation proximity switch 19 are 180 degrees out of phase and face each other in the diameter direction.
[0059]
On the outer peripheral surface of the annular nut member 17, a locking recess 17 c is formed in the spindle housing 1 where the locking portion of the clamping piston 18 contacts and separates, and the target 20 detected by the fixed position confirmation proximity switch 19 is further formed. Are provided in a predetermined range and in a predetermined range in the circumferential direction. In the illustrated example, the locking recess 17 c and the target 20 are 180 degrees out of phase with each other with the clamping piston 18 and the proximity switch 19.
[0060]
The operation of the spindle apparatus will be described.
As can be easily understood in FIG. 6, in the machining center, automatic tool change is performed by a process as shown in the drawing, and a desired machining process is performed.
When the machining process with one cutting tool is finished, in step 1, the control device determines whether or not the tool needs to be changed. As long as there is no command to change the tool, the machining with one cutting tool is repeated and the entire machining process is repeated. Is completed.
[0061]
When a tool change command is issued in order to replace the tool, in step 2, the used cutting tool is mounted and released in the spindle device, and in step 3, the used cutting tool is removed from the spindle by a tool changing arm (not shown). At the same time, a new cutting tool is inserted into the spindle.
[0062]
Next, in step 4, the new cutting tool is mounted and tightened in the main spindle device, and in step 5, the main spindle is rotationally driven to perform processing with the new cutting tool.
In step 6, the completion of all machining processes is determined by the control device. Unless all machining processes are completed, the process returns to step 1, and the above processes are repeated to complete all machining processes.
[0063]
Therefore, according to FIGS. 7, 9 and 11, the mounting / tightening / release of the cutting tool at the time of the above-described tool replacement in the spindle device of the embodiment (first and second) will be described.
For the sake of convenience, after describing the mounting and fastening of a new cutting tool to be used in the next process to the main spindle 4 following the release of the used cutting tool from the main spindle 4 in the tool change, the main spindle 4 of the cutting tool will be described. I will explain the release from the mounting.
[0064]
As shown in FIG. 3, FIG. 9 (a) and FIG. 11 (a), the tool holder of the used cutting tool is removed from the spindle 4 by tool replacement after the machining process with one cutting tool is completed. When the tool holder 41 of the new cutting tool 40 is mounted and tightened, the main shaft 4 is rotationally positioned at the rotation original position, and the annular nut member 17 protrudes and is pressed and engaged with the locking recess 17c. The piston 18 is fixed to the main shaft housing 1 so as not to rotate.
[0065]
The U-axis tension bar 7 is in the original position, which is the forward position, the tool clamp operating piece 15 is in the advanced position, and the U-axis operating bar clamp piece 16 is in the retracted position, thereby being separated from each other. The ball operating sleeve 14 is in the forward position, the collar 9 is in the retracted position, and the clamp ball 27 and the collet 13 are in an open state.
[0066]
Then, after the tool holder 41 of the used cutting tool 40 is removed from the spindle 4 by a tool changer arm (not shown), the tool holder 41 of the new cutting tool 40 is attached to the spindle 4 of the machine tool so as to be mounted. The annular groove 41 c of 41 is gripped by the replacement hand, and the taper shank 41 a is inserted into the tapered hole 5 of the main shaft 4. At that time, the temporary clamp ball 28 protruding into the tapered hole 5 by the spring force of the compression coil spring 29 is once pushed into the temporary clamp ball hole 5a by the taper shank 41a and then compressed again when it matches the clamp ball hole 41d. The taper shank 41 a is temporarily clamped to the main shaft 4 by being pushed into the clamp ball hole 41 d by the coil spring 29.
[0067]
Tool mounting and fastening will be described according to the process in FIG.
Step 1
In the control device 30, a tool mounting fastening command is output.
Step 2
Then, the all-axis machine lock command means 54 operates, and when the all-axis machine lock command is input to the gate circuit 55, the gate circuit 55 inputs the command from the U-axis feed command means 53 to the U-axis drive amplifier 38. Instead, it is switched to input to the U-axis position counting means 57.
[0068]
Step 3
Since the rotational position of the U-axis servomotor 33 is always detected by the encoder 35, the rotational position of the U-axis servomotor 33 when the U-axis tension rod 7 is set to the original position, that is, the tool holder 41 of the new cutting tool. The rotational angle position of the U-axis servomotor 33 at the time when the taper shank 41a is inserted into the tapered hole 5 of the main shaft 4 and temporarily clamped is stored from the encoder 35 into the U-axis current position storage means 56.
[0069]
Step 4
When commands are simultaneously input from the synchronous control command means 51 to the spindle rotation command means 52 and the U-axis feed command means 53, a spindle rotation command is input from the spindle rotation command means 52 to the spindle drive amplifier 37, and based on that. The built-in spindle motor 3 is driven to rotate. At the same time, a U-axis feed command is output from the U-axis feed command means 53 so that the U-axis servomotor 33 rotates in synchronization with the built-in spindle motor 3, but this is not input to the U-axis drive amplifier 38. Input to the shaft position counting means 57. That is, the U-axis servomotor 33 does not actually rotate in response to the command, but the rotation angle based on the synchronous rotation command with the built-in spindle motor 3 is sequentially input to the U-axis position counting means 57.
[0070]
When the built-in spindle motor 3 is driven to rotate, the spindle 4 is rotated counterclockwise. However, since the annular nut member 17 is prevented from rotating by the clamping piston 18, the tool clamp operating piece 15 and the U-axis operating rod are The clamp piece 16 is displaced so as to approach each other by a reverse screw. That is, the tool clamp operating piece 15 moves backward and the U-axis operating bar clamp piece 16 moves forward.
[0071]
As the tool clamp operating piece 15 is retracted, the clamp ball operating sleeve 14, that is, the clamp ball operating recess 4d, is retracted. The taper shank 41a is located on the base of the taper shank 41a by engaging with the rear inclined inner peripheral surface of the clamp ball hole 41d. The stepped portion is drawn into the tapered hole 5 so as to abut the tip end surface of the main shaft 4 and is fastened to the main shaft 4. That is, the tool holder 41 is attached to the main shaft 4 by two-surface restraint.
[0072]
When the taper shank 41a is fastened to the main shaft 4, the rear end surface of the U-axis actuating rod 42 of the tool holder 41 in the original position, that is, the pull stud 42a, of the tip member 12 of the U-axis tension bar 7 in the original position. It will contact | abut to a front end surface, and will be in the state which the pull stud 42a can be hold | gripped by the collet 13. FIG.
[0073]
On the other hand, as the U-axis actuating rod clamp piece 16 advances, the collar 9 advances with the spring force of the compression coil spring 10 while the stepped portion of the small diameter portion 9c is in contact with the rear end of the U-axis actuating rod clamp piece 16. Since the tapered surface 9d closes the collet 13 by the advancement of the collar 9, the collet 13 holds the pull stud 42a that is in contact with the distal end surface of the distal end member 12 of the U-axis tension rod 7 that is stopped at the original position. .
[0074]
Eventually, when the collet 13 grips the pull stud 42 a, the advancement of the collar 9 is prevented, and the U-axis actuating bar clamp piece 16 moves away from the step portion of the small diameter portion 9 c of the collar 9. As a result, the spring force of the compression coil spring 10 to be extended acts in the direction in which the collar 9 advances, and the engagement between the tapered surface 9d of the collar 9 and the collet 13, that is, the closing of the collet 13 is performed by the compression coil spring 10. As a result, the pull stud 42 a is completely coupled to the tip member 12 while being firmly in contact with the tip surface of the tip member 12.
[0075]
Step 5
As described above, the mounting and fastening is advanced, and when the mounting and fastening is completed, the tool clamp operating piece 15 is prevented from moving backward, and the load on the built-in spindle motor 3 is increased. That is, the built-in spindle motor 3 is decelerated and eventually stops. In view of this, the clamp determination means 58 determines whether or not the taper shank 41a has been fixed in the main shaft 4 based on the change in the detection signal input from the rotation speed sensor 36 that detects the rotation speed of the built-in main shaft motor 3.
[0076]
This mounting / tightening completion determination may be performed by the clamp determination means 58 based on a change in the detected torque signal by providing a torque sensor instead of the rotation speed sensor 36.
That is, it is determined that the fastening is completed when the detection speed at which the rotation speed sensor 36 decelerates or the detection torque at which the torque sensor increases reaches a predetermined value.
[0077]
Step 6
In the U-axis position counting means 57, the rotational angle position of the U-axis servo motor 33 at the time of temporary clamping inputted from the U-axis current position storage means 56 and the rotational angle of the virtual synchronous rotation of the built-in spindle motor 3 are used. The rotational angle position of the U-axis servomotor 33 during synchronous rotation is obtained and input to the U-axis skip position storage means 59.
Then, when a clamping completion determination signal that determines the completion of mounting and clamping is input from the clamp determination means 58 to the U-axis skip position storage means 59, the rotational angle position of the U-axis servo motor 33 at that time is the U-axis skip. It is stored in the position storage means 59.
[0078]
Step 7
Based on the rotation angle position of the U-axis servo motor 33 stored in the U-axis skip position storage means 59 in the spindle rotation amount calculation means 60, the rotation amount of the built-in spindle motor 3, that is, the rotation source required for tool mounting and fastening. The rotation angle of the spindle 4 from the position is calculated. In short, the rotation amount of the main shaft 4 is indirectly calculated by converting from the virtual synchronous rotation amount of the U-axis servomotor 33 with the built-in main shaft motor 3.
The rotation angle θ of the main shaft 4 from the rotation original position required for the tool mounting and fastening required as described above (that is, the rotation deviation angle from the rotation original position) is the shape and size of the taper shank of the cutting tool and the shank gripping portion. It is not constant depending on the dimensions of the.
[0079]
Step 8
Based on the rotation amount of the main shaft 4 from the rotation original position required for the tool mounting and tightening calculated by the main shaft rotation amount calculation means 60 in the rotation lock position storage means 61, the locking recess 17 c of the annular nut member 17 is formed. The rotational locking position facing the locking portion of the clamping piston 18 is stored. (See Fig. 9 (b) and Fig. 11 (b))
[0080]
Step 9
The all-axis machine lock command means 54 is activated, and an all-axis machine lock release command is input to the gate circuit 55. The gate circuit 55 inputs a command from the U-axis feed command means 53 to the U-axis drive amplifier 38. Switched.
Then, the ball screw nut 34 is rotated by a desired rotation angle by the U-axis servomotor 33 being driven to rotate by a desired rotation amount in response to a command signal from the control device 30.
[0081]
Accordingly, the ball screw 32 is retracted by a desired amount, which is transmitted to the U-axis tension bar 7 via the coupling 31, and the U-axis operating bar 42 coupled to the original U-axis tension bar 7 is in-situ. To the axial direction by a desired amount.
As a result, the cutting tool 40 is positioned at a desired radial position via the groove cam mechanism 43.
[0082]
Step 10
The clamping piston 18 is retracted by a fluid pressure control device (not shown) and detached from the locking recess 17 c of the annular nut member 17.
Accordingly, since the annular nut member 17 is rotatable with the main shaft 4, there is nothing that prevents the rotation of the main shaft 4, and the main shaft 4 can be driven to rotate by the built-in main shaft motor 3. (See Fig. 9 (c) and Fig. 11 (c))
[0083]
Thus, the cutting tool 40 of the new tool holder 41, which is mounted and fastened to the spindle 4 that is rotated by the rotational drive of the built-in spindle motor 3, rotates at a position offset by a desired amount from the center axis, and a desired machining diameter for the workpiece. Cutting is performed. Here, the rear end surface of the pull stud 42a of the U-axis operating rod 42 and the front end surface of the front end member 12 are completely in close contact, that is, the U-axis operating rod 42 and the U-axis tension rod 7 are connected without any gap in the axial direction. Therefore, the amount of radial displacement of the cutting tool 47 corresponding to the amount of movement of the U-axis tension bar 7 becomes accurate, and processing can be performed with high accuracy.
[0084]
Next, according to FIGS. 8 and 9, the mounting / release of the cutting tool at the time of the above tool change in the spindle device of the first embodiment will be described.
As described above, the machining process by the cutting tool 40 of the tool holder 41 mounted and fastened to the main shaft 4 is completed, and the main shaft 4 is positioned and stopped at a predetermined rotation original position. (See FIG. 9 (d) and FIG. 11 (d))
[0085]
Tool release will be described according to the process in FIG.
Step 11
In the control device 30, a tool mounting release command is output.
Step 12
In order to release the tool holder 41, the locking recess 17c of the annular nut member 17 must be opposed to the clamping piston 18 in order to fix the annular nut member 17. However, since the main shaft 4 is positioned and stopped at a predetermined rotation original position, the locking recess 17c of the annular nut member 17 has a rotation angle θ (FIG. 9) when the main shaft 4 is rotated counterclockwise for tool mounting fastening. (See (b)) is displaced from the position of the clamping piston 18 only. (See Fig. 9 (d))
[0086]
Therefore, the control device 30 calls the rotation lock position stored in the rotation lock position storage means 61 at the time of the tool mounting and fastening described above, and the built-in spindle motor 3 is moved to the position by the control command from the control device 30. Is rotated clockwise by a rotation angle corresponding to (360 ° −θ). As a result, the locking recess 17c of the annular nut member 17 that rotates clockwise together with the main shaft 4 by the rotation angle (360 ° −θ) is positioned so as to face the clamping piston 18. (See Fig. 9 (e))
[0087]
Step 13
The clamping piston 18 in the retracted state protrudes by the operation of a fluid pressure control device (not shown) based on the advance command of the control device 30 and is pressed and engaged with the locking recess 17 c of the annular nut member 17. That is, the annular nut member 17 is fixed to the main shaft housing 1 so as not to rotate. (See Fig. 9 (f))
[0088]
Step 14
In the control device 30, the built-in main shaft motor 3 is controlled and driven, and the main shaft 4 rotates clockwise and is positioned and stopped at a predetermined rotation original position.
When the main shaft 4 is rotated clockwise until it reaches the rotation original position, the rotation of the annular nut member 17 is blocked by the clamping piston 18, so that the tool clamp operating piece 15 and the U-axis operating rod clamp piece 16 are They are displaced so as to be separated from each other by a reverse screw. That is, the tool clamp operating piece 15 moves forward, and the U-axis operating bar clamp piece 16 moves backward. When the main shaft 4 is positioned and stopped at a predetermined rotation original position, the tool clamp operation piece 15 is located at the most advanced position, and the U-axis operation bar clamp piece 16 is located at the last retracted position.
[0089]
As a result, the clamp ball operating sleeve 14, that is, the clamp ball operating recess 14 d, that is, the edge slope 14 b advances, so that the clamp ball 27 is released from the edge slope 14 b and the clamp ball hole of the taper shank 41 a of the tool holder 41 is released. The temporary clamp ball 28 is pressed by the compression coil spring 29 and engaged with the clamp ball hole 41d of the taper shank 41a of the tool holder 41.
Therefore, as shown in FIG. 3, the taper shank 41a of the tool holder 41 is released from the fastening with respect to the main shaft 4 and is temporarily clamped.
[0090]
On the other hand, the rear end of the retracting U-axis actuating rod clamp piece 16 abuts on the step portion of the small diameter portion 9 c of the collar 9 and further retracts the collar 9 appropriately against the spring force of the compression coil spring 10. As a result, the tapered surface 9d of the collar 9 is separated from the outer peripheral surface of the collet 13 of the U-axis tension bar 7 in the initial position, so that the collet 13 is opened and the pull stud 42a of the U-axis operating bar 42 of the tool holder 41 is opened. release.
[0091]
The state of the main shaft 4 is a state before starting the operation of removing the tool holder of the used cutting tool in the tool change described above from the main shaft 4 and mounting and fixing the tool holder of a new cutting tool on the main shaft 4. (See Fig. 9 (a))
Next, according to FIGS. 10 and 11, the mounting / release of the cutting tool at the time of the above tool change in the spindle device of the second embodiment will be described.
The positioning stop state at a predetermined rotation original position of the spindle 4 at the end of the machining process by the cutting tool 40 of the tool holder 41 attached and fastened to the spindle 4 is the same as that in the first embodiment described above. (See FIG. 11 (d))
[0092]
Tool release will be described according to the process in FIG.
Step 11
In the control device 30, a tool mounting release command is output.
Step 12
As in the first embodiment described above, when positioning the locking recess 17c of the annular nut member 17 so as to face the clamping piston 18, the controller 30 rotates at the time of the tool mounting and fastening described above. A position offset by an appropriate angle (δ) from the rotation locking position stored in the locking position storage means 61 is called, and the built-in spindle motor 3 rotates corresponding to the offset position by a control command from the control device 30. It is rotated clockwise by an angle (360 ° −θ + δ). (See FIG. 11 (e))
[0093]
Step 13
The built-in spindle motor 3 rotates in a low-speed inching direction counterclockwise in response to a control command from the control device 30.
Step 14
A target 20 provided in the annular nut member 17 with a phase difference of 180 degrees from the locking recess 17c is detected by a proximity position confirmation proximity switch 19 provided in the spindle housing 1 with a phase difference of 180 degrees with respect to the clamping piston 18. As a result, a stop command is applied to the build-in spindle motor 3, and the build-in spindle motor 3 is stopped and positioned.
As a result, the locking recess 17 c of the annular nut member 17 that rotates integrally counterclockwise with the main shaft 4 is positioned so as to face the clamping piston 18. (See FIG. 11 (f))
[0094]
In this case, in the case of the first embodiment described above, the annular nut member 17 and the U-axis actuating rod clamp piece 16 are used when the rotation positioning is performed only by the rotation locking position stored in the rotation locking position storage means 61. Even if there is a deviation from the actual rotational locking position, which may occur due to the lubrication state or the like in the screw mechanism, the locking recess 17c in the annular nut member 17 is accurately positioned in the clamping piston 18. Are positioned opposite to each other.
Steps 15 and 16
This is the same as steps 13 and 14 in the first embodiment described above. (See FIGS. 11 (g) and (a))
[0095]
【The invention's effect】
According to the spindle device of the present invention, the spindle at the predetermined rotation original position can be efficiently rotationally positioned at another desired stop position.
For example, when removing a used cutting tool in automatic tool change, the spindle stopped at a predetermined rotation original position is moved to the tool mounting release screw mechanism operation start position (nut member). Rotation lock It is possible to shorten the time for rotational positioning to the position. Eventually, the tool change time can be shortened.
[0096]
In addition, the function means for recognizing the spindle rotation angle phase, which is expensive for detecting the spindle rotation position, for example, is provided at the predetermined rotation original position in a shortened time without providing a proximity switch that requires an installation space near the spindle. The spindle can be rotationally positioned at another desired stop position.
[0097]
Even if a proximity switch is installed, only one proximity switch is installed, and the actual tool installation release screw type mechanism start position (nut member fastening position) due to the lubrication state of the tool installation release screw type mechanism, etc. Even if there is a deviation from the position stored in the control device, the tool mounting release screw type mechanism start position (nut member Rotation lock Position).
[Brief description of the drawings]
FIG. 1 is a configuration diagram of a spindle device according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view of a front half portion of a spindle device (tool holder mounted and fastened state) in an embodiment of the present invention.
FIG. 3 is a cross-sectional view of the front half of the spindle device (tool holder mounted and released state) according to the embodiment of the present invention.
4 is a cross-sectional view taken along line IV-IV in FIG.
FIG. 5 is a configuration diagram of a tool attachment / detachment control function of the control device of the spindle device in the embodiment of the present invention.
FIG. 6 is a flowchart of a tool change / machining process of the spindle device according to the embodiment of the present invention.
FIG. 7 is a flowchart of a tool holder mounting fastening process of the spindle device according to the embodiment of the present invention.
FIG. 8 is a flowchart of a tool holder mounting / releasing process of the spindle device according to the first embodiment of the present invention.
FIG. 9 is an explanatory diagram of a tool holder mounting fastening / releasing operation of the spindle device according to the first embodiment of the present invention.
FIG. 10 is a flowchart of a tool holder mounting / releasing process of the spindle device according to the second embodiment of the present invention.
FIG. 11 is an explanatory diagram of a tool holder mounting fastening / releasing operation of the spindle device according to the second embodiment of the present invention.
FIG. 12 is a flowchart of a conventional tool holder mounting / fastening process of a spindle device.
FIG. 13 is a flowchart of a tool holder mounting / releasing process of the spindle device in the prior art.
FIG. 14 is an explanatory view of a tool holder mounting fastening / releasing operation of a spindle device in the prior art.
FIG. 15 is a graph showing the relationship between the spindle rotational speed and the operating time of the tool holder mounting fastening / releasing operation of the spindle device in the prior art.
[Explanation of symbols]
1 Spindle housing 2 Rolling bearing
3 Build-in spindle motor 4 Spindle
4a annular groove 5 taper hole
5a Temporary clamp ball hole 6 Through hole
7 U-axis tension rod 7a 1st small diameter part
7b Second small diameter part 8 Tension sleeve
9 Color 9a Long hole
9b Large diameter part 9c Small diameter part
10, 29 Compression coil spring 11 Stop pin
12 Tip member 13 Collet
14 Clamp ball operating sleeve 14a, 14b Center hole
14c Front edge slope 14d Clamp ball operation recess
14e Engagement protrusion 15 Tool clamp operation piece
16 U-axis actuating rod clamp piece 15a, 16a Screw part
17 annular nut member 17a first screw part
17b Second screw portion 17c Locking recess
17d cylinder 18 piston for clamping
19 Proximity switch for fixed position confirmation 20 Target
24 Radial void 25 Clamp ball holding sleeve
25a Clamp ball hole 27 Clamp ball
28 Temporary clamp ball 29 Compression coil spring
30 Controller 31 Coupling
32 Ball screw 33 U-axis servo motor
34 Ball screw nut 35 Encoder
36 Rotational speed sensor 37 Spindle drive amplifier
38 U-axis drive amplifier 40 Cutting tool
41 Tool holder 41a Taper shank
42 U-axis operating rod 42a Pull stud
43 Groove cam mechanism
51 Synchronous control command means 52 Spindle rotation command means
53 U-axis feed command means 54 All-axis machine lock command means
55 Gate circuit 56 U-axis current position storage means
57 U-axis position counting means 58 Clamp determination means
59 U-axis skip position storage means 60 Spindle rotation amount calculation means
61 Rotation locking position storage means

Claims (2)

A main shaft that is rotatably supported; a main shaft motor that rotationally drives the main shaft; a shank gripping portion that is provided on the main shaft and fastens and releases a shank of a tool; and is provided on the main shaft so as to be axially displaceable. A shank gripper operating member for opening and closing the shank gripper; an annular nut member provided concentrically and rotatably with respect to the main shaft, and having an internal thread formed on an inner periphery thereof; annular nut member fixing means for non-rotatably securing the member; integrally with respect to the main shaft in the rotational direction, and is provided retractably in the axial direction, is screwed into the internal thread portion of the annular nut member, said shank gripping A tool clamp actuating piece coupled to a part actuating member ; and a main unit comprising a main unit motor and a control device for controlling a drive motor of a rotating member different from the main shaft. A shaft device ,
The control device is
Clamp determination means for determining in the rotational drive of the main shaft motor that the shank gripping portion of the shank gripping part has been completed by the rotational drive of the main shaft motor in a state where the annular nut member cannot rotate; in synchronization with the rotation of the main shaft motor A control signal for rotationally driving a driving motor of a rotating member different from the main shaft is sent to a driving amplifier that directly applies driving of the driving motor, or is directly applied to driving of the driving motor when the shank gripping portion is fixed to the shank. Synchronous rotation control means that is alternatively sent to the counting means ; storage means for storing the virtual rotation amount of the drive motor based on the control signal sent to the counting means during the shank fixing operation ; sometimes, in the rotational situ in a state in which the annular nut member by the annular nut member fixing means is unrotatable Shi Driving said main shaft of the link released state the rotation angle of rotation from the rotating original position to the shank locking completion position is a rotational position of the spindle motor when it is determined by said clamping determining means, stored in said storage means Calculation means for calculating from the virtual rotation amount of the motor ; and rotation lock position storage means for storing a rotation lock position in which the rotation angle calculated by the calculation means is added to the rotation original position of the spindle.
Comprising:
Rotatably driving said spindle shank solid fastening a stopped state to the rotating original position when the shank released from the rotational original position to the stored the rotation locking position to the rotation locking position storage means; said rotary locking position The main shaft device is configured to control the main shaft motor so as to rotate the main shaft to the rotation original position after the annular nut member fixing means makes the annular nut member non-rotatable. A main shaft that is rotatably supported; a main shaft motor that rotationally drives the main shaft; a shank gripping portion that is provided on the main shaft and fastens and releases a shank of a tool; and is provided on the main shaft so as to be axially displaceable. A shank gripper operating member for opening and closing the shank gripper; an annular nut member provided concentrically and rotatably with respect to the main shaft, and having an internal thread formed on an inner periphery thereof; annular nut member fixing means for non-rotatably securing the member; integrally with respect to the main shaft in the rotational direction, and is provided retractably in the axial direction, is screwed into the internal thread portion of the annular nut member, said shank gripping part tool clamp actuation piece coupled to the actuating member; detector for detecting the rotational locking position of the main shaft to be coupled to the annular nut member; and the spindle motor and the The axis a spindle device and a control device for controlling the drive motor of another rotary member,
The control device is
Clamp determination means for determining in the rotational drive of the main shaft motor that the shank gripping portion of the shank gripping part has been completed by the rotational drive of the main shaft motor in a state where the annular nut member cannot rotate; in synchronization with the rotation of the main shaft motor A control signal for rotationally driving a driving motor of a rotating member different from the main shaft is sent to a driving amplifier that directly applies driving of the driving motor, or is directly applied to driving of the driving motor when the shank gripping portion is fixed to the shank. synchronizing rotation control means is alternatively or send et no counting means; memory means in the shank fixing operation for storing a virtual rotation of the drive motor based on the control signal sent to the counting means; shank fastening sometimes, in the rotational situ in a state in which the annular nut member by the annular nut member fixing means is unrotatable Shi Driving said main shaft of the link released state the rotation angle of rotation from the rotating original position to the shank locking completion position is a rotational position of the spindle motor when it is determined by said clamping determining means, stored in said storage means Calculation means for calculating from the virtual rotation amount of the motor ; rotation locking position storage means for storing the rotation locking position in which the rotation angle calculated by the calculation means is added to the rotation original position of the main shaft; and the rotation source of the main shaft A rotation lock position storage means for storing a rotation lock position in consideration of the rotation angle calculated by the calculation means and a position offset with respect to the rotation lock position ;
The main shaft in the shank-tightened state stopped at the rotation original position when the shank is released is driven to rotate from the rotation original position to a position offset with respect to the rotation engagement position in the rotation engagement position storage means , and further, the detection Until the rotational locking position by the detector is detected; and at the rotational locking position detected by the detector, the annular nut member fixing means makes the annular nut member non-rotatable, A spindle device configured to control the spindle motor so as to rotate the spindle to a rotation original position.

Images