JPH0788736A - Spindle part control device for machine tool - Google Patents

Abstract

PURPOSE:To detect the position of a tool with accuracy by providing a sensor for detecting the position of the tool, directly at a face plate, and providing drive mechanism for driving the sensor together with the face plate in the radial direction of the face plate. CONSTITUTION:The tip 18a of a tool 18 is put in rectilinear motion in the radial direction of a hollow rotating shaft 3 so as to increase the radial depth of cut to a workpiece W. The workpiece W can be machined as far as the innermost side of the inner peripheral recessed part by moving the tool 18 and the workpiece W relatively in the axial direction of the workpiece W. At this time, a sensor 20 is moved together with a face plate 17, along a spindle, so that the moving quantity of the tool 18 is detected by detecting the moving quantity of the sensor 20 at this time. On the basis of this detected information, a motor 4 is driven to position the tool 18 to the workpiece W with high accuracy.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spindle control device for a machine tool, and more particularly to a spindle control device provided on a machine tool for performing facing, recessing, boring and the like.

[0002]

2. Description of the Related Art Generally, in a machine tool for performing facing processing and recessing processing (grooving), it is necessary to move a tool in a radial direction during processing. Further, also in a machine tool for boring, if the tool can be set at an arbitrary position in the radial direction, it is possible to machine a desired hole diameter without exchanging the tool, which is useful. For this reason,
Recently, there has been a machine tool equipped with a spindle control unit to automatically adjust the position of the tool. Then, in this machine tool, the position of the tool is detected, and the position of the tool is automatically adjusted based on the detection information.
Conventionally, the position of the tool is detected by various methods.

As a conventional spindle control device for a machine tool of this type, there is, for example, one described in Japanese Utility Model Laid-Open No. 4-5302. This device mounts a face plate that is movable in the radial direction in front of a hollow rotary shaft that rotates integrally with the main shaft of a machine tool, and supports the tool on this face plate.It is a long drawbar that can move in the axial direction of the main shaft. Is housed inside the hollow rotary shaft, and the draw bar and the face plate are connected via a tapered surface.

The draw bar is pushed and pulled in the axial direction of the main shaft by a motor provided on the fixed side. When the draw bar is pushed and pulled, the draw bar is tapered along the tapered surface of the face plate. By moving the face plate in the radial direction, the position of the tool is automatically adjusted to an arbitrary position. In addition, in this spindle control device, an encoder that detects the rotation amount of the motor is provided on the fixed side, and this detection is performed by indirectly detecting the movement amount when the draw bar is pushed and pulled by the encoder. The position of the tool is controlled based on the information.

On the other hand, as a spindle control device for setting the position of the cutting edge to an arbitrary position in the radial direction, for example, a rotating body rotatably supported by a supporting body and a front portion of the rotating body are radiated. A machine tool provided with a face plate that is linearly movable in a direction, and a tool attached to the face plate, the motor being provided in a rotating body, and the motor provided between the motor and the face plate. And a face plate moving mechanism that converts the rotation of the blade into a linear motion in the radial direction of the face plate, and the blade edge position is automatically adjusted to an arbitrary position via the motor and the face plate moving mechanism.

In this device, a face plate having a tool attached thereto is moved by a motor to control the position of the cutting edge, but the rotary member having the face plate attached thereto is rotatably supported by a support. Therefore, it is necessary to send and receive an electrical signal between the support and the rotating body, and various measures have been taken to send and receive an electrical signal from the fixed support to the rotating rotating body.

As a conventional spindle control device of this type,
There is one in which a contact type connecting means such as a carbon brush and a slip ring is interposed between a support and a rotating body, and an electric current is supplied to a motor through the slip ring. Further, as other spindle control devices, for example, Japanese Patent Publication No. 3-5886.
There is something like that described in Japanese Patent Publication No. 0, which is
A rotary connector, which is rotatable with the rotating body and has a conductive liquid such as mercury inside, is interposed between the rotating body and the support body, and current is supplied from the support body to the motor on the rotating body side through the conductive liquid. I have to.

[0008]

However, in the spindle control unit equipped with the former sensor, since the encoder detects the amount of movement of the drawbar pushed and pulled in the axial direction of the spindle, the temperature of the drawbar is detected. In the case of the change, the encoder also detected the thermal deformation amount of the drawbar as the movement amount, and the actual position of the tool could not be detected.

In addition to the amount of thermal deformation of the draw bar, when the face plate is thermally deformed in the radial direction, or the face plate drive unit from the output shaft of the motor to the face plate, that is, the connecting portion between the output shaft of the motor and the draw bar, or the face plate. Due to the influence of the non-linear part such as the play and the play of the drawbar coupling part, the accurate movement amount of the tool cannot be detected, and the position control of the tool cannot be performed accurately.

Therefore, conventionally, since it is not possible to accurately control the positioning of the tool, when it is necessary to position the tool with an accuracy of several microns, it is possible to perform positioning on the order of substantially micron. could not. On the other hand, in the latter spindle control device that adopts the latter current supply structure, the contact resistance between the slip ring and the brush is large, so the slip ring wears out after long-term use, and the motor is powered by power. Can no longer be supplied. For this reason,
There is a problem in that it is necessary to replace the slip ring on a regular basis, which increases the maintenance cost of the spindle control device.

Further, since the abrasion powder of the slip ring may be scattered inside the rotating body, when the abrasion powder adheres to the sliding surfaces of the rotating body and the supporting body, the rotating body can be sufficiently supported. There is a problem that the life of the main shaft portion is shortened as well as being impossible. Further, in order to extend the life of the main shaft portion, it is conceivable that the sliding surface is not covered with abrasion powder by an air curtain or the like, but in such a case, the cost of the device increases. Something went wrong.

Further, when the contact between the carbon brush and the slip ring becomes unstable, electricity is momentarily cut off, and the sensor malfunctions when current is supplied to the signal processing system such as the sensor. There was a problem. further,
Since the case containing a conductive liquid such as mercury was interposed between the rotating body and the support, the conductive liquid may leak from the case, causing an electrical short circuit and destroying the electrical system. , The motor might not work. In addition to this, there is a possibility that ignition or the like may be induced by a short circuit, which causes a problem that safety is deteriorated.

Further, when the conductive liquid leaks from the case or the life of components such as bearings is shortened, the rotor connector must be periodically replaced.
As in the case described above, there is a problem that the maintenance cost of the spindle control device increases. Further, in the rotary connector, since the terminal on the support body side and the terminal on the rotary body side are connected via the conductive liquid, there is a problem that the structure of the terminal portion becomes complicated and the cost increases.

Therefore, it is desired to stably supply the electric current from the supporting body to the electric equipment such as the motor provided on the rotating body. Therefore, an object of the present invention is to provide a spindle control device for a machine tool that can perform highly accurate positioning of a tool. According to a second aspect of the present invention, between the rotating body and the support body, a power generating means for generating power according to the rotation of the rotating body is interposed, and the power generating means is connected to various electric equipments, whereby various electric equipments are provided. It is an object of the present invention to provide a low-cost machine tool spindle control device that can stably supply current to the machine tool.

According to a third aspect of the present invention, the rotating body is provided with a battery for storing electromotive force generated by the power generation means, and the battery is connected to various electric devices.
An object of the present invention is to provide a spindle control device for a machine tool that can supply current from a battery to various electric devices when the rotation of a rotating body is stopped. According to a fourth aspect of the present invention, a battery for supplying electric current to various electric devices is provided in the rotating body, and the battery is charged by the charging means when the rotating body is stopped or at low rotation, so that the various electric devices are stably provided. An object of the present invention is to provide a low-cost machine tool spindle control device that can supply an electric current.

[0016]

In order to achieve the above object, the invention according to claim 1 has a hollow rotary shaft rotatably supported by a support, and a radial linear motion at the front of the hollow rotary shaft. A machine tool comprising a face plate freely provided and a tool attached to the face plate, the drive mechanism having a rotation output shaft provided in the hollow rotation shaft, and the rotation output of the drive mechanism. A bevel gear that is connected to the shaft and is capable of converting the rotation generated by the drive mechanism into a rotation about a rotation center axis in a direction orthogonal to the axis of the hollow rotation shaft; and a bevel gear that meshes with the axis direction of the hollow rotation shaft. A rotatable ball screw extending in the orthogonal direction, a ball screw nut screwed onto the ball screw and fixed to the face plate, and movable along the axis of the ball screw as the ball screw rotates, and a hollow rotation. A shaft member provided in the front part of the shaft, extending in a direction orthogonal to the axis of the hollow rotation shaft, a sensor guided by the shaft member and fixed to a face plate, and a sensor capable of detecting the position of the tool; It is characterized by having.

To achieve the above object, the invention according to claim 2 is a machine tool having a rotating body rotatably provided on a support and a tool provided on the rotating body, the machine tool being provided on the rotating body. In a spindle control device for a machine tool that supplies electric current to various electric devices, a power generation unit that generates power in accordance with the rotation of the rotating body is provided, and the power generation unit includes a stator provided on a support body and a stator. A rotor provided on the rotating body so as to face the stator and connected to various electric devices;
It is characterized by supplying electric current to various electric devices by electromotive force generated by rotation of the rotor.

To achieve the above object, the invention according to claim 3 is the invention according to claim 2, wherein the rotating body is provided with a battery for storing electromotive force generated by the power generation means, and the battery is used for various electric devices. It is characterized by being connected to. In order to achieve the above object, the invention according to claim 4 is a machine tool having a rotating body rotatably supported by a supporting body and a tool provided on the rotating body, and various electric machines provided on the rotating body. In a spindle control device of a machine tool for supplying a current to a device, a battery for supplying a drive current to the electric devices, and a charging means for contacting a battery terminal when the rotating body is stopped or at low speed to charge the battery. It is characterized by having.

[0019]

According to the first aspect of the invention, the sensor for detecting the position of the tool is directly provided on the face plate, and the sensor is driven by the drive mechanism to move in the radial direction together with the face plate. Therefore, the sensor directly detects the position of the tool, and even if the face plate is thermally deformed, the sensor is not affected by this thermal deformation, so that the position of the tool is accurately detected. The face plate is positioned with high accuracy based on.

Further, since the distance between the tool and the sensor is not separated as in the conventional case, the face plate drive section between the tool and the sensor,
That is, the position of the tool is detected with high accuracy without being affected by rattling of the bevel gear or the like. Further, since the sensor is provided in the front part of the hollow rotary shaft and moves along with the face plate by being guided by the shaft member extending in the direction orthogonal to the axis of the hollow rotary shaft, the accuracy in detecting the position of the tool is significantly improved. It

According to the second aspect of the present invention, the power generation means for generating power according to the rotation of the rotary body is interposed between the rotary body and the support body, and the power generation means is connected to various electric devices. Therefore, the electric current is stably and surely supplied from the power generation means to the various electric devices during the rotation of the rotating body, and it is not necessary to regularly replace the slip ring and the conductive liquid. As a result, the maintenance cost of the spindle control device is reduced.

Further, since the electric current is supplied by the power generation means, it is not necessary to interpose a slip ring or the like between the support and the rotating body, and the abrasion powder does not scatter in the rotating body. As a result, the rotating body is smoothly rotated with respect to the supporting body, the life of the main spindle portion is extended, and it is not necessary to provide an air curtain for removing abrasion powder on the sliding surface between the rotating body and the supporting body. The cost of parts is reduced.

Further, unlike an electrically conductive liquid, an electrical short circuit does not occur, and an electric system does not ignite or a sensor malfunctions. In addition, since the contact does not become unstable like a slip ring, malfunction of various electric devices does not occur. In the invention according to claim 3, the rotating body is provided with a battery for storing the electromotive force generated by the power generation means, and the battery is connected to various electric devices. Therefore, electric power is reliably and stably supplied to various electric devices even when the rotating body is stopped.

According to a fourth aspect of the present invention, a battery for supplying a drive current to various electric devices is provided in the rotating body, and a charging means for charging the battery by contacting the battery terminal when the rotating body is stopped or at low rotation speed. Is provided. Therefore, the electric current is stably supplied from the battery to various electric devices, and it is not necessary to perform regular replacement unlike the slip ring and the conductive liquid. As a result, the maintenance cost of the spindle control device is reduced.

Further, since the current is supplied by the battery, it is not necessary to interpose a slip ring or the like between the support and the rotating body, and the abrasion powder does not scatter in the rotating body. As a result, the rotating body is smoothly rotated with respect to the supporting body, the life of the main spindle portion is extended, and it is not necessary to provide an air curtain for removing abrasion powder on the sliding surface between the rotating body and the supporting body. The cost of parts is reduced.

Further, unlike the conductive liquid, an electrical short circuit does not occur, and an electric system does not ignite or a motor does not operate properly. Moreover, since the electric current is supplied to various electric devices only by providing the rotating body with the battery, the structure of the electric system becomes very compact. Furthermore, since the battery is charged when the rotating body is stopped or at low speed, the battery is reliably charged when it is not necessary to process the workpiece. As a result, the electric current is reliably and stably supplied from the battery to various electric devices.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. 1 to 5 are views showing an embodiment of a spindle control device for a machine tool according to the present invention. First,
The configuration will be described.

1 to 3, reference numeral 1 denotes a main body case (support) of a machine tool such as a machining center, and the main body case 1 can be moved in three dimensions by the machine tool. A hollow rotating shaft 3 as a rotating body is rotatably supported in the main body case 1 via a plurality of bearings 2. Lubricating oil is supplied to the bearing 2 from an oil passage 1a formed in the main body case 1. It is like this. A drive belt 3a is in sliding contact with the outer periphery of the hollow rotary shaft 3 on the rear side, and the rotating body 3 is rotated by this belt 3a. The belt 3a is wound around a pulley (not shown) and driven by this pulley.

Inside the hollow rotary shaft 3, a step motor (motor) 4 as an electric device constituting a drive mechanism is housed. The step motor 4 is supported by the hollow rotary shaft 3 and the output shaft The (rotary output shaft) 4a side is fixed to the front plate 5. Front plate 5
Are attached to the first member 7 via bolts 6, and the first member 7 is attached to the second member 9 via bolts 8. The second member 9 is fixed to the hollow rotary shaft 3 via a bolt 10. The hollow rotary shaft 3, the front plate 5, the first member 7 and the second member 9 are integrally formed with the main body case 1. It is designed to rotate.

On the other hand, one gear 11a of the bevel gear 11 is attached to the output shaft 4a of the step motor 4, and the other gear 11b of this bevel gear 11 is meshed with the ball screw 12. Therefore, the rotating force of the step motor 4 is converted by the bevel gear 11 into rotation about the center axis of rotation in the direction orthogonal to the axis of the hollow rotating shaft 3, and the ball screw 12 is rotated by this rotating force. .

The ball screw 12 extends in a direction orthogonal to the axial direction of the hollow rotary shaft 3, and both ends thereof are rotatably supported by a guide member 14 via bearings 13. Also,
Side plates 15 are provided at both ends of the ball screw 12, and the ball screw 12 is prohibited from moving in the axial direction by the side plates 15. Also the side plate
An oil passage 15a is formed in 15 and this oil passage 15a is a bearing.
It is designed to supply lubricating oil to 13. The guide member 14 and the side plate 15 are attached to the first member 14 by bolts or the like (not shown).

The ball screw 12 has a ball screw nut.
A ball screw nut 16 is attached, and the ball screw nut 16 moves in the axial direction of the ball screw 12 as the ball screw 12 rotates. A face plate 17 is provided at the front of the hollow rotary shaft 3.
Is attached, and this face plate 17 is a ball nut screw 16
Installed on. Therefore, the face plate 17 moves together with the ball screw nut 16 in the axial direction of the ball screw 12. Further, a tool 18 is detachably provided at the center of the front surface of the face plate 17, and a tip 18a constituting a cutting edge of the tool 18 faces one side in the moving direction of the face plate 17.

This tool 18 rotates together with the hollow rotary shaft 3 and the face plate 17 and cuts, for example, the inner peripheral concave portion of the work W with the tip 18a, and the linear movement of the face plate 17 laterally feeds the cutting edge position (radiation inside). To move outward or radiating). Then, the position of the cutting edge is finely adjusted by converting the rotation of the step motor 4 into the radial movement of the face plate 17 via the bevel gear 11, the ball screw 12, and the ball screw nut 16.

Further, the face plate 17 is provided with a sensor 20 which is an electric device for detecting the position of the tool 18, and the sensor 20 is fixed to the guide member 14 as shown in FIG. The main body 32, which is guided by a spindle (shaft member) 31 extending in a direction orthogonal to the axial direction of the shaft 3 and is fixed to the face plate 17, and the tip portion of the spindle 31, are arranged alternately. A magnetic scale 33 having N and S magnetic poles, a detection head 34 disposed near the magnetic scale 33 and generating a resistance by detecting a magnetic flux generated from the magnetic scale 33, and a resistance detected by the detection head 34. And an amplifier 35 for amplifying the value.

In the sensor 20, when the main body 32 moves together with the face plate 17, the resistance value of the detection head 34 periodically changes due to the movement of the detection head 34 with respect to the magnetic scale 33. Is detected as the amount of movement of the face plate 17. Then, this resistance value is amplified by the amplifier 35, then transmitted to the machine tool side via the wiring 36, and the change in the resistance value is counted by the controller of the machine tool, whereby the movement distance of the face plate 17, that is, The tool moving distance (tool feed amount) is detected. Therefore, the position of the tool 17 is detected based on this moving distance.

On the other hand, as shown in FIG. 2, a battery 22 constituting an electric device is housed inside the hollow rotary shaft 3, and the battery 22 includes a motor 4, a sensor 20 and a controller 21 constituting the electric device. Is connected to the motor 4 and supplies current to these motors 4 and the like. The positive electrode 22a and the negative electrode 22b (battery terminals) of the battery 22 are a slip ring 23 provided on the outer peripheral portion of the hollow rotating shaft 3,
One end of the positive electrode brush 25 and one end of the negative electrode brush 26 are in contact with the slip rings 23, 24 as shown in FIGS. The other ends of the brushes 25 and 26 are attached to a brush attachment plate 27 and connected to a power source (not shown).

The brush mounting plate 27 is screwed into a ball screw 28, and the ball screw 28 is driven to rotate by a motor 29. Therefore, when the motor 29 is driven, the brush mounting plate 27 is moved in the vertical direction (the direction of the arrow in FIG. 5) by the ball screw 28, so that the brushes 25, 26 are brought into contact with and separated from the slip rings 23, 24. It When one ends of the brushes 25 and 26 are brought into contact with the slip rings 23 and 24, the battery 22 is passed through the brushes 25 and 26, the slip rings 23 and 24, and the positive electrode 22a and the negative electrode 22b of the battery 22.
Is charged.

Further, one end of the brush mounting plate 27 is slidably mounted on the linear guide 30a, and the brush mounting plate 27 is guided by the linear guide 30a and guided vertically in FIG. It has become. The linear guide 30a and the motor 29 are attached to the fixed portion 30,
The fixed portion 30 is attached to the machine tool body. Further, a control means (not shown) is connected to the motor 29, and this control means controls the rotation state of the hollow rotary shaft 3, for example,
Based on the output information of the sensor that detects the rotation speed, the motor 29
Motor to move the brushes 25, 26 downward in FIG. 5 when the hollow rotary shaft 3 is stopped or at low speed.
Rotate 29 in one direction and slip brushes 25 and 26 into slip rings.
The battery 22 is charged by bringing it into contact with 23 and 24.

That is, the above-mentioned slip rings 23, 2
4, brush 25, 26, brush mounting plate 27, ball screw 28,
The motor 29, the linear guide 30a, and the fixed portion 30 constitute a charging means 38 that charges the battery 22 when the hollow rotary shaft 3 is stopped or at low speed. Reference numeral 37 is a lead wire connecting the step motor 4 and the controller 21.
Next, the operation will be described.

First, in the state before the work W is processed, since the hollow rotary shaft 3 is stopped, the brushes 25, 26 are
Is in contact with the slip rings 23, 24 and the battery 22 is charged via the brushes 25, 26 and the slip rings 23, 24. Therefore, the step motor 4 and the sensor
Current is supplied from the battery 22 to the controller 20 and the controller 21.

On the other hand, when the work W is machined, first, as a preparatory work, the work W is held by a work holding means (not shown), and the tool 18 and the work W are moved relative to each other so that the tip 18a of the tool 18 and the work W are Close to the circumferential recess. Then, when the step motor 4 is operated, the rotational force of the motor 4 is changed by the bevel gear 11 to the rotation center axis in the direction orthogonal to the axial direction of the hollow rotary shaft 3 and transmitted to the ball screw 12. This transmission force is transmitted to the ball screw nut 16, and the ball screw nut 16 moves in the axial direction of the ball screw 12 to move the face plate 17 in that direction. For this reason, the tool 18
The tip 18a linearly moves in the radial direction of the hollow rotary shaft 3 (radial direction of the work W) to increase the depth of cut into the work W in the radial direction. Further, by relatively moving the tool 18 and the work W in the work axis direction, the work W is machined to the inner side of the inner peripheral concave portion.

At this time, since the sensor 20 moves along with the face plate 17 along the spindle 31, it is possible to detect the moving amount of the tool 18 by detecting the moving amount at this time by the sensor 20. By driving the motor 4 based on the information, the tool 18 can be positioned with respect to the work W with high accuracy. At this time, when the rotation speed of the hollow rotary shaft 3 becomes high, the control means drives the motor 29 in the other direction based on the output information of the sensor that detects the rotation speed of the hollow rotary shaft 3. At this time, the ball screw 28 moves the brush mounting plate 27 upward in FIG. 5 to separate the brushes 25, 26 from the slip rings 23, 24 and stop the charging of the battery 22. Therefore, the hollow rotary shaft 3 rotates at high speed without the brushes 25 and 26 coming into contact with the slip rings 23 and 24.

Then, when the processing of the work W is completed and the rotation speed of the hollow rotary shaft 3 becomes low, the control means drives the motor 29 in one direction based on the output information of the sensor. At this time, the ball screw 28 moves the brush mounting plate 27 to the position shown in FIG.
Move the brushes 25 and 26 to the middle and downward to slip ring 2
The battery 22 is charged by bringing it into contact with the batteries 3 and 24 again. As described above, in this embodiment, the sensor that detects the position of the tool 18 is used.
Since 20 is directly provided on the face plate 17 and the sensor 20 is driven by the motor 4 together with the face plate 17 in the radial direction of the face plate 17,
The sensor 20 can directly detect the position of the tool, and even when the face plate 17 is thermally deformed, it can be prevented from being affected by this thermal deformation, and the position of the tool 18 can be accurately detected. The face plate 17 can be positioned with high accuracy based on this detection information.

In addition to this, since the distance between the tool 18 and the sensor 20 does not become large, it is possible to prevent the face plate drive portion between the tool 18 and the sensor 20, that is, the influence of rattling of the bevel gear 11 and the like. The position of the tool 18 can be detected with high accuracy. Further, since the sensor 20 is fixed to the front part of the hollow rotary shaft 3 and guided by the spindle 31 extending in the direction orthogonal to the axis of the hollow rotary shaft 3 and moved together with the face plate 17, the position of the tool 18 is reduced. The detection accuracy can be significantly improved.

Further, a battery 22 for supplying a drive current to electric equipment such as the step motor 4, the sensor 20 and the controller 21 in the hollow rotary shaft 3, and a positive electrode of the battery 22 when the hollow rotary shaft 3 is stopped or at low speed. Since the charging means 38 for contacting the batteries 22a and 22b and charging the battery 22 is provided, it is possible to stably supply the current from the battery 22 to the step motor 4, the sensor 20 and the controller 21, and the slip ring or It is possible to eliminate the need for periodic replacement like a conductive liquid. As a result, the maintenance cost of the spindle control device can be reduced.

Further, since current is supplied by the battery 22, it is not necessary to interpose a slip ring or the like between the main body case 1 and the hollow rotary shaft 3, and abrasion powder is stored in the hollow rotary shaft 3 inside. It is possible to prevent scattering.
As a result, the hollow rotary shaft 3 can be smoothly rotated with respect to the main body case 1, the life of the main shaft portion can be extended, and the sliding surface between the hollow rotary shaft 3 and the main body case 1 can be provided with air for removing abrasion powder. It is not necessary to provide a curtain or the like, and the cost of the spindle can be reduced.

Further, unlike an electrically conductive liquid, an electrical short circuit does not occur, so that it is possible to prevent ignition of the electric system and malfunction of the step motor 4, the sensor 20 and the controller 21. Further, since the electric current can be supplied to the step motor 3, the sensor 20 and the controller 21 only by providing the battery 22 on the hollow rotary shaft 3, the structure of the electric system can be made very compact.

Further, since the battery 22 is charged when the hollow rotary shaft 3 is stopped or at low speed, the battery 22 can be reliably charged when it is not necessary to process the work W, and the step motor is used. 4 and the sensor 20 can be reliably and stably supplied with current from the battery 22. In this embodiment, the brushes 25, 26 are made to contact and separate from the slip rings 23, 24 as the charging means, but the charging means is not limited to this, and the hollow rotary shaft 3 is stopped. Any other structure may be used as long as it is in contact with the positive electrode 22a and the negative electrode 22b at the time of low speed or low rotation.

FIGS. 6 and 7 are views showing a second embodiment of the spindle control device for a machine tool according to the present invention. In this embodiment, the structure of the drive mechanism is different from that of the above-described embodiment, that is, the driving by the motor is not performed, and the driving method of the current to the battery or the bevel gear or the ball screw for driving the face plate is different. Since the configuration is the same as that of the above-described embodiment, the same components as those described above are designated by the same reference numerals and the description thereof is omitted.

In FIGS. 6 and 7, reference numeral 1 denotes a main body case as a support, and a hollow rotary shaft 3 is rotatably supported by the support 1 via a plurality of bearings 2. A main shaft driving motor 41 is attached to the main body case 1, and the motor 41 is connected to the hollow rotary shaft 3 via a belt 42.
The hollow rotary shaft 3 is rotated via the belt 42.

Further, a face plate positioning motor 43 is attached to the main body case 1, and an output shaft of the motor 43 is attached.
A ball screw 44 is attached to 43a via a reduction mechanism 40. The ball screw 44 is screwed into a ball screw nut 45, and the nut 45 is supported by a bracket 46. In FIG. 6, the lower end of the bracket 46 is slidably provided to a guide 47 fixed to the main body case 1, and the guide 47 extends along the axial direction of the hollow rotary shaft 3. Therefore, when the motor 43 operates, the ball screw 44 decelerated by the speed reduction mechanism 40 rotates, so that the bracket 46 is guided through the ball screw nut 45.
It is guided by 47 and moves in the axial direction of the hollow rotary shaft 3.

Further, a pair of cam followers 48a and 48b are provided on the upper end portion of the bracket 46 in FIG. 6, and the cam followers 48a and 48b hold the flange portion 49a of the slide ring 49 therebetween. The slide ring 49 is provided on the outer peripheral portion of the hollow rotary shaft 3 so as to be slidable in the axial direction of the rotary shaft 3, and when the guide 47 moves in the axial direction of the hollow rotary shaft 3, the cam followers 48a, 48b. Is the flange 49
By sandwiching a, it moves in the axial direction of the hollow rotary shaft 3.

A slit 3a is formed in the hollow rotary shaft 3 substantially in the center in the axial direction. A connecting rod 50 is provided in the slit 3a. The connecting rod 50 has slide rings at both ends. 49 is installed. Also, connecting rod
A cylindrical bush 51 is attached to the center of 49, and the bush 51 is slidably provided inside the hollow rotary shaft 3. Therefore, the slide ring 49 is a connecting rod.
It is connected to the bush 51 via 50, and slides on the inner peripheral portion of the hollow rotary shaft 3 as the slide ring 49 slides in the axial direction of the hollow rotary shaft 3.

A ball screw nut 52 is fixed inside the bush 51, and the nut 52 has a ball screw nut.
53 is screwed. The tip of the ball screw 53 is connected to one gear 11a of the bevel gear 11. Therefore, when the bush 51 slides on the inner peripheral portion of the hollow rotary shaft 3,
The ball screw 53 rotates to rotate one gear 11a of the bevel gear 11.
Rotates.

The speed reduction mechanism 40, the face plate positioning motor 43, the ball screws 44 and 53, the ball screw nut 45,
52, bracket 46, guide 47, cam follower 48a, 48
b, the slide ring 49, the connecting rod 50, and the bush 51 constitute a drive mechanism 54, and the ball screw 53 constitutes a rotation output shaft. In this embodiment, in order to move the face plate 17 in the radial direction of the hollow rotary shaft 3, the motor 43 is operated and the ball screw 44 is rotated. At this time, the bracket 46 is guided by the guide 47 via the ball screw nut 45 and moves in the axial direction of the hollow rotary shaft 3, so that the cam followers 48a and 48b sandwich the flange portion 49a, whereby the slide ring 49 rotates in the hollow direction. It moves in the axial direction of the shaft 3.

When the slide ring 49 moves, the connecting rod 50
Since the bush 51 slides on the inner peripheral portion of the hollow rotary shaft 3 via the ball screw 53 via the ball screw nut 52, the bevel gear 11 causes the center of rotation in the direction orthogonal to the axial direction of the hollow rotary shaft 3. Axis changed to ball screw 12
Be transmitted to. Since the subsequent operation is the same as that of the above-mentioned embodiment, the explanation is omitted.

Therefore, even in this embodiment, the face plate 17
At the same time, the sensor 20 is moved along the spindle 31, and the amount of movement at this time can be detected by the sensor 20, and the same effect as that of the above embodiment can be obtained. Further, since the method of charging the battery and the method of driving the current from the battery to the sensor 20 and the like are the same as those in the above-described embodiment, the same effect as that in the above-described embodiment can be obtained.

FIG. 8 is a diagram showing an embodiment of a spindle control device for a machine tool according to the invention described in claims 2 and 3. The present embodiment is characterized in that instead of the charging means, a power generation means for generating power in accordance with the rotation of the hollow rotary shaft is provided, and current is supplied from the power generation means to electric equipment such as a motor. Is the same as each of the above-described embodiments, and therefore, the same components are denoted by the same reference numerals and description thereof is omitted.

A rotor coil 71 is provided on the rear side of the hollow rotary shaft 3.
This coil 71 is connected to the voltage regulator 72 provided in the hollow rotary shaft 3 via a wire.
The voltage regulator 72 is connected to the pulse motor 4, the sensor 20 and the controller 21 (a part of the connecting line is omitted to avoid making the figure complicated), and the voltage is adjusted to the sensor 20, etc. Is to be supplied to. Further, a battery 22 is provided in the hollow rotary shaft 3, and the battery 22 is connected to the rotor coil 71 via the voltage regulator 72, and also connected to the pulse motor 4, the sensor 20 and the controller 21. ing.

A stator coil 73 is provided on the main body case 1 facing the rear side of the hollow rotary shaft 3, and this coil 73 generates a predetermined magnetic field. Therefore, an electromotive force is generated in the rotor coil 71 with the rotation of the hollow rotary shaft 3, and the electromotive force is adjusted by the voltage regulator 72, and then the battery 22, the pulse motor 4, the sensor 20, and the controller 21 are provided. Supplied. That is, the coil rotor 71 and the stator coil 73 are interposed between the hollow rotary shaft 3 and the main body case 1, and constitute a power generation unit that generates power as the hollow rotary shaft 3 rotates.

In this embodiment, while the hollow rotary shaft 3 is rotated by the drive belt 3a, the tool 18 and the work W are relatively moved so that the tip 18a of the tool 18 and the inner peripheral concave portion of the work W are brought close to each other. At this time, the coil 71 cuts off the magnetic field generated in the coil 73 as the hollow rotary shaft 3 rotates, and
Electromotive force is generated in the voltage regulator 72, and this electromotive force is supplied to the voltage regulator 72. The electromotive force supplied to the voltage regulator 72 is adjusted to a predetermined voltage, and then the battery 22, the pulse motor 4,
It is supplied to the sensor 20 and the controller 21, and the sensor 20 and the like are driven.

On the other hand, when the rotation of the hollow rotary shaft 3 is stopped, no voltage is generated in the coil 71, so that no current is supplied from the coil 71 to the sensor 20 or the like. However, since the electromotive force generated during the rotation of the hollow rotary shaft 3 is stored in the battery 22, current is supplied from the battery 22 to the sensor 20, the motor 4, etc., and the hollow rotary shaft 3 is not rotated. At this time, for example, the position of the face plate 18 can be adjusted through the face plate moving mechanism 19 by operating the motor 4 at the time of assembling and adjusting the main shaft portion or at the time of performance inspection at the work site.

As described above, in this embodiment, the hollow rotary shaft 3 and the main body case 1 are provided with the rotor coil 71 and the stator coil 73 which generate electric power as the hollow rotary shaft 3 rotates.
Since the rotor coil 71 is connected to the sensor 20, the motor 4 and the controller 21, the current can be reliably and stably supplied to the sensor 20, the motor 4 and the controller 21. For this reason, it is possible to eliminate the need for periodic replacement such as with a slip ring or a conductive liquid. As a result, the maintenance cost of the spindle control device can be reduced. Further, since the electric power is supplied by the power generation action of the coils 71, 73 accompanying the rotation of the hollow rotary shaft 3, it is not necessary to interpose a slip ring or the like between the main body case 1 and the hollow rotary shaft 3. It is possible to prevent the abrasion powder from scattering in the hollow rotary shaft 3. As a result, the hollow rotary shaft 3 can be smoothly rotated with respect to the main body case 1, the life of the main shaft portion can be extended, and abrasion powder can be removed from the sliding surface of the hollow rotary shaft 3 and the main body case 1. It is possible to reduce the cost of the main shaft portion by eliminating the need for an air curtain or the like.

Further, unlike an electrically conductive liquid, an electrical short circuit does not occur, so that it is possible to prevent ignition of an electric system and malfunction of a sensor. In addition to this, since the contact does not become unstable like a slip ring, it is possible to prevent malfunction of the sensor 20, the motor 4, and the controller 21.

Further, since the battery 22 is provided in the hollow rotary shaft 3 and is connected to the rotor coil 71, the sensor 20, the motor 4 and the controller 21, the battery 22 is connected to the battery 22 while the hollow rotary shaft 3 is rotating. It can be charged, and the battery will be charged when the rotation of the hollow rotary shaft 3 stops.
Can supply current to the sensor 20, the motor 4, and the controller 21. As a result, it is possible to reliably supply the current to the sensor 20 and the like even when the hollow rotary shaft 3 is stopped.

In this embodiment, the pulse motor 4 is provided inside the hollow rotary shaft 3 and the face plate 17 is driven from the pulse motor 4 via the face plate moving mechanism 19.
It is not limited to such an aspect. For example, the present invention may be applied to a main shaft portion of a machine tool that merely moves a main body case that supports the hollow rotary shaft without providing a motor and a controller inside the hollow rotary shaft. In this case, it suffices to provide only the sensor as an electric device on the hollow rotating shaft and supply the sensor with electric power from the power generation means. Further, although the hollow rotating shaft 3 is driven by the drive belt 3a in the present embodiment, the present invention is not limited to this, and a motor or the like is attached to the rear side of the hollow rotating shaft 3 so that the hollow rotating shaft 3 is driven by this motor. You can

[0067]

According to the present invention, the sensor for detecting the position of the tool is directly provided on the face plate, and the sensor is driven together with the face plate in the radial direction of the face plate by the sensor. The position of the tool can be detected, and even if the face plate is thermally deformed, it can be prevented from being affected by this thermal deformation, and the position of the tool can be detected accurately and based on this detection information. The face plate can be positioned with high accuracy.

In addition to this, since the distance between the tool and the sensor is not separated as in the conventional case, it is possible to prevent the face plate drive section between the tool and the sensor, that is, the influence of rattling of the bevel gear or the like. Therefore, the position of the tool can be detected with high accuracy. Furthermore, since the sensor is guided by a shaft member that is fixed to the front part of the hollow rotary shaft and extends in a direction orthogonal to the axis of the hollow rotary shaft and is moved together with the face plate, the accuracy of tool position detection is greatly improved. Can be improved.

According to the second aspect of the present invention, the electric current can be stably supplied from the power generating means to the various electric devices, and it is not necessary to perform the periodical replacement such as the slip ring and the conductive liquid. be able to. As a result, the maintenance cost of the spindle control device can be reduced. In addition, since the current is supplied by the power generation means that generates power in accordance with the rotation of the rotating body, it is not necessary to interpose a slip ring or the like between the support and the rotating body, and the abrasion powder is rotated. It can be prevented from scattering in the body. As a result, the rotating body can be smoothly rotated with respect to the support body, the life of the main shaft portion can be extended, and an air curtain for removing abrasion powder or the like can be provided on the sliding surface between the rotating body and the support body. It is possible to reduce the cost of the main shaft portion by making it unnecessary to provide it.

Further, unlike an electrically conductive liquid, an electrical short circuit does not occur, so that it is possible to prevent ignition of an electric system or malfunction of various electric devices. In addition to this, since the contact does not become unstable like a slip ring, it is possible to prevent malfunction of various electric devices. According to the third aspect of the invention, the battery can be charged while the rotating body is rotating, and when the rotating body stops rotating, electric power can be supplied from the battery to various electric devices. As a result, electric power can be reliably and stably supplied to various electric devices even when the rotating body is stopped.

According to the invention described in claim 4, it is possible to stably supply current to various electric devices from the battery,
It can eliminate the need for regular replacement such as slip rings and conductive liquids. As a result, the maintenance cost of the spindle control device can be reduced. Also, since the current is supplied by the battery, it is not necessary to interpose a slip ring or the like between the support and the rotating body,
It is possible to prevent the abrasion powder from scattering in the rotating body. As a result, the rotating body can be smoothly rotated with respect to the supporting body, and the life of the main shaft portion can be extended,
It is not necessary to provide an air curtain or the like for removing abrasion powder on the sliding surface between the rotating body and the support, and the cost of the main shaft portion can be reduced.

Further, unlike the conductive liquid, an electrical short circuit does not occur, so that it is possible to prevent ignition of the electric system and malfunction of the sensor. Also,
Since the electric current can be supplied to the motor only by providing the rotating body with the battery, the structure of the electric system can be made very compact. Furthermore, since the battery is charged when the rotating body is stopped or at low speed, the battery can be reliably charged when there is no need to process the workpiece, and the electric current from the battery to various electrical devices can be charged. It can be reliably and stably supplied.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing a first embodiment of a spindle control device for a machine tool according to the invention described in claim 1 or 4.

FIG. 2 is a schematic configuration diagram of an electric system inside the hollow rotary shaft.

FIG. 3 is a schematic configuration diagram of the sensor.

FIG. 4 is a perspective view of the charging means.

FIG. 5 is a front view of the charging means.

FIG. 6 is an overall configuration diagram showing a second embodiment of a spindle control device for a machine tool according to the invention described in claim 1 or 4.

FIG. 7 is a sectional view of a front portion of the hollow rotary shaft.

FIG. 8 is a schematic configuration diagram showing an embodiment of a spindle control device for a machine tool according to a second or third aspect of the present invention.

[Explanation of symbols]

 1 Body case (support) 3 Hollow rotary shaft (rotary body) 4 Pulse motor (electrical device) 4a Output shaft (rotary output shaft) 11 Bevel gear 12 Ball screw 16 Ball screw nut 17 Face plate 18 Tool 20 Sensor (electrical device) 21 Controller ( Electrical equipment) 22 Battery 22a Positive electrode (battery terminal) 22b Negative electrode (battery terminal) 31 Spindle (shaft member) 38 Charging means 53 Ball screw (rotary output shaft) 54 Drive mechanism 71 Rotor coil (power generation means) 73 Stator coil (power generation means)

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location B23Q 1/00 8107-3C 17/22 Z 9423-3C (72) Inventor Shigeru Hobouchi Aichi Prefecture Toyota City, Toyota-cho, Toyota Motor Co., Ltd. (72) Inventor, Kazutori Asano Toyota-cho, Toyota-shi, Aichi Prefecture Toyota Motor Co., Ltd.

Claims (4)

[Claims] 1. A hollow rotary shaft rotatably supported by a support, a face plate provided on a front portion of the hollow rotary shaft so as to be linearly movable in a radial direction, and a tool attached to the face plate. A machine tool comprising: a drive mechanism having a rotary output shaft provided in the hollow rotary shaft; and rotation generated by the drive mechanism, which is coupled to the rotary output shaft of the drive mechanism, with an axis line of the hollow rotary shaft. A bevel gear that can be converted into rotation about a rotation center axis in an orthogonal direction, a rotatable ball screw that meshes with the bevel gear and extends in a direction orthogonal to the axial direction of the hollow rotation shaft, and a screw that engages with the ball screw. Mounted on the face plate and movable along the axis of the ball screw as the ball screw rotates, and a ball screw nut that is provided at the front of the hollow rotating shaft and extends in the direction orthogonal to the axis of the hollow rotating shaft. A spindle control device for a machine tool, comprising: an existing shaft member; and a sensor which is guided by the shaft member and is fixed to a face plate and which is capable of detecting the position of a tool. 2. A machine tool having a rotating body rotatably provided on a support and a tool provided on the rotating body, the machine tool supplying electric current to various electric devices provided on the rotating body. In the main shaft portion control device, a power generation unit that generates power in accordance with the rotation of the rotary body is provided, and the power generation unit is provided on the stator provided on the support body and on the rotary body so as to face the stator, A spindle control device for a machine tool, comprising a rotor connected to various electric devices, and supplying electric current to the electric devices by an electromotive force generated by the rotation of the rotor. 3. A spindle control device for a machine tool according to claim 2, wherein the rotating body is provided with a battery for storing electromotive force generated by the power generation means, and the battery is connected to various electric devices. . 4. A machine tool having a rotating body rotatably supported by a support and a tool provided on the rotating body, the machine tool supplying an electric current to various electric devices provided on the rotating body. The main shaft control device includes a battery that supplies a drive current to the various electric devices, and a charging unit that contacts the battery terminal when the rotating body is stopped or at low speed to charge the battery. Machine tool spindle control device.