JP2020031488A - Power generation device and spindle device - Google Patents

Abstract

To provide a power generation device capable of generating a predetermined DC voltage even if rotation speed of a rotation member largely fluctuates, and a spindle device having the power generation device.SOLUTION: A power generation device 9 for generating a predetermined DC voltage by rotation of a main shaft 10 includes: a plurality of first magnets 81 and second magnets 82 mounted onto a housing 11; a power generation coil 31 attached to the main shaft 10 and interlinked with magnetic flux of the first magnets 81 and the second magnets 82; a rectifier circuit 32 for converting an AC voltage generated by the power generation coil 31 into a DC voltage; a first voltage converter 33 and a second voltage converter 34 capable of converting an input voltage supplied from the rectifier circuit 32 into a voltage of a specified value to output it; and an output circuit unit 35 for selectively outputting any of output voltages of the first voltage converter 33 and the second voltage converter 34. The first voltage converter 33 and the second voltage converter 34 have a different range of an input voltage necessary for outputting a voltage of a predetermined value.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a power generation device that generates a predetermined DC voltage by rotation of a rotating member with respect to a fixed member, and a spindle device including the power generation device.

  Conventionally, for example, in a spindle device used for a machine tool, an AC voltage is generated by rotation of a magnet attached to a spindle as a rotating member, and the spindle is supported using a DC voltage obtained by rectifying and smoothing the AC voltage. There is one that supplies lubricating oil to rolling bearings (see, for example, Patent Document 1).

  The lubricating oil supply device described in Patent Literature 1 is wound around a ring-shaped multipolar magnet embedded in an inner race spacer arranged between the inner races of a pair of rolling bearings, and an iron core arranged non-rotatably. A generator is constituted by the generated coil. The AC voltage generated by the generator is converted to DC by an AC / DC converter and stored in a capacitor. The DC power stored in the capacitor is supplied to electronic components such as a CPU of the control unit and a plurality of sensors. The plurality of sensors include a temperature sensor that detects the temperature of the rolling bearing and a speed sensor that detects the rotation speed of the rolling bearing. The CPU controls the electromagnet of the refueling unit based on the detection signals of these sensors, and moves the valve body forward and backward by the magnetic force of the electromagnet to open and close the nozzle. When the nozzle is opened, the lubricating oil stored in the tank is discharged to the rolling bearing.

JP 2013-92238 A

  The AC voltage generated by the generator configured as described above changes according to the rotation speed of the main shaft. On the other hand, it is necessary to supply a voltage in a predetermined range as a DC power supply to a control unit having a CPU and various sensors. For this reason, in the lubricating oil supply device described in Patent Literature 1, even if the lubricating oil can be discharged to the rolling bearings when the rotation speed of the main shaft is maintained in a predetermined speed range, the lubricating oil supply device does not exceed the speed range. If the rotation speed is low or high, an appropriate DC voltage cannot be supplied to the control unit.

  Therefore, the present invention provides a power generation device capable of generating an appropriate predetermined DC voltage for operating, for example, an electronic component even if the rotation speed of the rotation member relative to the fixed member fluctuates greatly, and a power generation device capable of generating the predetermined DC voltage. An object of the present invention is to provide a spindle device provided with the same.

  In order to achieve the above object, the present invention is a power generation device that generates a predetermined DC voltage by rotation of a rotating member with respect to a fixed member, wherein a magnet attached to one of the fixed member and the rotating member A coil attached to the other of the fixed member and the rotating member, the magnetic flux of the magnet interlinking, a rectifier circuit for converting an AC voltage generated by the coil into a DC voltage, and a rectifier circuit. A plurality of voltage converters capable of increasing or decreasing the supplied input voltage to a specified voltage and outputting the selected voltage; and selectively outputting any one of the output voltages of the plurality of voltage converters. And a plurality of voltage converters, wherein the plurality of voltage converters have different input voltage ranges required to output the specified voltage.

  Further, in order to achieve the above object, the present invention provides a control circuit unit using a DC voltage generated by the power generator as a power supply, a spindle as the rotating member, and the spindle controlled by the control circuit unit. And a pump for discharging a lubricating oil for smooth rotation of the main shaft.

  ADVANTAGE OF THE INVENTION According to the power generator concerning this invention, even if the rotational speed of the rotating member with respect to a fixed member fluctuates greatly, it becomes possible to generate | occur | produce predetermined DC voltage. Further, according to the spindle device according to the present invention, it is possible to appropriately supply the lubricating oil even if the rotation speed of the spindle largely fluctuates.

It is a sectional view showing the example of composition of the spindle device concerning an embodiment of the invention. It is sectional drawing of a spindle device in the cross section perpendicular | vertical with respect to the rotation axis of a spindle. FIG. 3 is a circuit diagram illustrating a schematic configuration example of a power supply circuit unit. 5A is a graph showing a temporal change in the voltage of each part of the power supply circuit unit, where FIG. 5A shows the output voltage of the rectifier circuit, FIG. 5B shows the input voltage to the first voltage conversion unit, and FIG. (D) shows the output voltage of the second voltage conversion unit, and (e) shows the output voltage of the output circuit unit. It is a schematic diagram which shows the structural example of a pump part, (a) shows the state when a voltage is not applied to a piezo element, (b) shows the state when a voltage is applied to a piezo element.

[Embodiment]
An embodiment of the present invention will be described with reference to FIGS. The embodiments described below are shown as preferred specific examples for carrying out the present invention, and there are portions specifically illustrating various technical matters that are technically preferable. However, the technical scope of the present invention is not limited to this specific embodiment.

  FIG. 1 is a sectional view illustrating a configuration example of a spindle device according to an embodiment of the present invention. FIG. 2 is a sectional view of the spindle device in a section perpendicular to the rotation axis of the spindle. FIG. 1 is a sectional view taken along line AA in FIG.

  The spindle device 1 is used for processing a workpiece in a machine tool such as a machining center, a grinding machine, or a lathe. The spindle device 1 includes a main shaft 10 as a rotating member, a housing 11 as a fixed member having a first housing member 111 and a second housing member 112, and a pair of rolling members that rotatably support the main shaft 10 with respect to the housing 11. It has bearings 12, a motor unit 13 having a stator 131 and a rotor 132, and a lubricating oil supply device 2 that supplies lubricating oil to the pair of rolling bearings 12. The housing 11 is non-rotatably fixed to, for example, a saddle provided so as to be position adjustable with respect to the base of the machine tool.

  The main shaft 10 integrally has a large-diameter portion 101 accommodated in a first housing member 111 and a small-diameter portion 102 accommodated in a second housing member 112, and rotates about a rotation axis O. Hereinafter, a direction parallel to the rotation axis O is referred to as an axial direction. The first housing member 111 and the second housing member 112 are arranged side by side in the axial direction, and are connected by unillustrated bolts. The rotor 132 of the motor section 13 has a plurality of magnetic poles, and is fixed to the outer peripheral surface of the large-diameter section 101 of the main shaft 10. In the stator 131, an excitation coil 131b is wound around a plurality of cores 131a attached to the first housing member 111. A motor current is supplied to the excitation coil 131b from a host controller (not shown). The main shaft 10 rotates with respect to the housing 11 by the torque of the motor unit 13 to rotate a tool, a grindstone or a workpiece.

  Each of the pair of rolling bearings 12, 12 has an inner ring 121 fitted on the small diameter portion 102 of the main shaft 10, an outer ring 122 fitted on the second housing member 112, and a track formed on the outer peripheral surface of the inner ring 121. And a plurality of spherical rolling elements 123 that roll on a raceway surface 122a formed on the surface 121a and the inner peripheral surface of the outer ring 122. The lubricating oil supply device 2 is disposed as a spacer between the pair of rolling bearings 12. In other words, the lubricating oil supply device 2 is axially sandwiched between the pair of rolling bearings 12,12.

  Of the pair of rolling bearings 12, 12, the inner ring 121 of one of the rolling bearings 12 disposed on the inner side of the second housing member 112 (on the side of the first housing member 111) has one side surface 121 b having a large diameter of the main shaft 10. The inner ring fixing nut 14 screwed into the screw portion 103 of the main shaft 10 abuts on the step surface 10 a between the portion 101 and the small diameter portion 102, and contacts one side surface 121 c of the inner ring 121 of the other rolling bearing 12. I have. The outer ring 122 of one rolling bearing 12 has one side surface 122b abutting on a contact surface 112a provided on the second housing member 112, and one side surface 122c of the outer ring 122 of the other rolling bearing 12 has An outer ring fixing member 15 fixed to an end of the two housing member 112 is in contact with the outer ring fixing member 15.

  As shown in FIG. 2, the lubricating oil supply device 2 receives an annular case member 20 made of a non-magnetic material, a power supply circuit unit 3 accommodated in the case member 20, and a supply of DC power from the power supply circuit unit 3. A control circuit section 4 and a sensor circuit section 5; a tank 6 for storing the lubricating oil L; a pump section 7 operated by an electric signal supplied from the control circuit section 4; and an annular magnet section 8 attached to the main shaft 10 And The power supply circuit section 3, the control circuit section 4, the sensor circuit section 5, the tank 6, and the pump section 7 are connected by electric wires 21 to 24, respectively.

  The case member 20 is disposed between the outer rings 122 of the pair of rolling bearings 12, and is fixed to the second housing 112 of the housing 11. The case member 20 houses the power supply circuit section 3, the control circuit section 4, the sensor circuit section 5, the tank 6, and the pump section 7. The magnet portion 8 is arranged between the inner rings 121 of the pair of rolling bearings 12 and is fixed to the small-diameter portion 102 of the main shaft 10.

  The control circuit unit 4 includes a CPU 41, a memory IC 42 that stores a program executed by the CPU 41, a switching element 43 that generates an electric signal to be supplied to the pump unit 7 by switching, and communication for performing communication with a higher-level controller. An IC 44 and the like are mounted on the circuit boards 401 and 402. Further, the control circuit section 4 has a battery 45 for supplying power to the CPU 41 and the like even when the main shaft 10 is in the rotation stopped state. DC power is supplied to the control circuit unit 4 from the power supply circuit unit 3 via the electric wire 21.

  In the sensor circuit section 5, various sensors such as a vibration sensor 51 and a temperature sensor 52, and an amplifying element 53 such as a transistor for amplifying an output signal of these sensors are mounted on a circuit board 50. Further, a magnetic field sensor for detecting the rotation speed of the main shaft 10 based on the magnetic field of the magnet unit 8 may be mounted on the circuit board 50. DC power is supplied to the sensor circuit unit 5 from the power supply circuit unit 3 through the electric wire 22. Detection signals indicating various physical quantities detected and amplified in the sensor circuit unit 5 are sent to the control circuit unit 4 via the electric wires 23.

  The magnet portion 8 includes a plurality of first magnets 81 whose N poles face the outer circumference side and S poles face the inner circumference side, and a plurality of second magnets 82 whose S poles face the outer circumference side and the N pole faces the inner circumference side. , A cylindrical inner sleeve 83 arranged on the inner periphery of the plurality of first magnets 81 and the second magnets 82, and a cylindrical outer sleeve 84 arranged on the outer periphery of the plurality of first magnets 81 and the second magnet 82 And The plurality of first magnets 81 and the second magnets 82 are alternately arranged along the circumferential direction, and a non-magnetic spacer 80 made of, for example, resin is provided between the first magnets 81 and the second magnets 82. It is arranged interposed. The inner sleeve 83 and the outer sleeve 84 are made of a non-magnetic metal such as austenitic stainless steel.

  The inner sleeve 83 is fixed to the outer peripheral surface of the small diameter portion 102 of the main shaft 10 by, for example, bonding. The plurality of first magnets 81 and second magnets 82 are attached to the main shaft 10 via the inner sleeve 83, and rotate integrally with the main shaft 10 together with the inner sleeve 83 and the outer sleeve 84. A slight gap (air gap) is formed between the outer sleeve 84 and the inner peripheral surface of the case member 20. The magnet unit 8 constitutes a power generation device 9 together with the power supply circuit unit 3.

  FIG. 3 is a circuit diagram illustrating a schematic configuration example of the power supply circuit unit 3. The power supply circuit unit 3 includes a circuit board 30 (see FIG. 2), a power generation coil 31 in which magnetic fluxes of the first magnet 81 and the second magnet 82 of the magnet unit 8 are linked, and a diode obtained by combining four diodes 321 to 324. A rectifier circuit 32 composed of a bridge; a first voltage converter 33 and a second voltage converter 34 having different output voltage to input voltage ratios supplied from the rectifier circuit 32; a first voltage converter 33 and a second voltage An output circuit unit for selectively outputting any one of the output voltages of the conversion unit; and a first voltage conversion unit configured to output the first voltage conversion signal when the output voltage of the rectification circuit exceeds a predetermined value. And a cutoff circuit section 36 for cutting off the voltage supply to the section 33.

  The power generation coil 31 is mounted on the circuit board 30, and the circuit board 30 is fixed to the case member 20. Thereby, the power generation coil 31 is attached to the housing 11 via the circuit board 30 and the case member 20. When the main shaft 10 rotates, the direction and magnitude of the magnetic flux linked to the power generation coil 31 change, and an AC voltage is generated in the power generation coil 31. The frequency and the effective value of the AC voltage generated in the power generation coil 31 increase as the main shaft 10 rotates at a higher speed. The rectifier circuit 32 performs full-wave rectification on the AC voltage generated in the power generation coil 31 and converts it to DC.

  The DC voltage converted to DC by the rectifier circuit 32 is input to the first voltage conversion unit 33 via a photocoupler 367 (described later) as a cutoff element of the cutoff circuit unit 36. The DC voltage converted by the rectifier circuit 32 into DC is always directly input to the second voltage converter 34.

  The first voltage converter 33 is a step-up voltage converter that steps up an input voltage and outputs the boosted voltage. The first voltage converter 33 can boost the input voltage supplied from the rectifier circuit 32 to a voltage having a specified value and output the same. . The second voltage converter 34 is a step-down voltage converter that steps down an input voltage and outputs the same, and can step down the input voltage supplied from the rectifier circuit 32 to a specified voltage and output the same. . That is, the first voltage conversion unit 33 and the second voltage conversion unit 34 differ from each other in the range of the input voltage required to output the voltage of the specified value. The specified value of the output voltage of the first voltage converter 33 and the specified value of the output voltage of the second voltage converter 34 are the same value. Here, the specified value refers to a target value of a voltage to be output.

  The first voltage converter 33 has a boost regulator IC 331, a boost coil 332 and a smoothing capacitor 333 connected to the boost regulator IC 331, and the boost coil 332 is turned on / off by a switching element built in the boost regulator IC 331. The input voltage is boosted and output by repeating the accumulation and release of the energy. The second voltage converter 34 has a step-down regulator IC 341, a step-down coil 342 connected to the step-down regulator IC 341, and a smoothing capacitor 343. The input voltage is reduced and output by adjusting the amount of current flowing through the coil 342.

  The specified value of the output voltage of the first voltage conversion unit 33 and the second voltage conversion unit 34 is a voltage value that allows for a voltage drop in the output circuit unit 35 with respect to the operating voltage of the electronic component such as the CPU 41 in the control circuit unit 4. Yes, for example, 4V. That is, the first voltage converter 33 boosts the input voltage to the specified voltage and outputs the same, and the second voltage converter 34 lowers the input voltage to the specified voltage and outputs the same. In addition, the second voltage conversion unit 34 does not output a voltage when the input voltage (average value) is less than a specified value of the output voltage.

  The output circuit unit 35 includes a first diode 351 to which the output voltage of the first voltage conversion unit 33 is input to the anode, and a second diode 352 to which the output voltage of the second voltage conversion unit 34 is input to the anode. And a diode OR circuit in which the cathode of the first diode 351 and the cathode of the second diode 352 are connected. The output circuit unit 35 supplies the higher one of the output voltages of the first voltage converter 33 and the second voltage converter 34 to the control circuit unit 4 via the electric wire 21.

  The cutoff circuit unit 36 includes a divided voltage obtained by dividing the output voltage of the second voltage conversion unit 34 by the resistors 361 and 362 and a divided voltage obtained by dividing the output voltage of the rectifier circuit 32 by the resistors 363 and 364. The comparator has a comparator 365 for comparing the output voltage and a photocoupler 367 to which an output voltage of the comparator 365 is supplied via a resistor 366. Here, the photocoupler 367 serves as a switch of the cutoff circuit unit 36. The resistance values of the resistors 361 to 364 are determined so that the supply of the voltage from the rectifier circuit 32 to the first voltage converter 33 is cut off when the output voltage of the rectifier circuit 32 becomes a predetermined value or more.

  This predetermined value is a value higher than the specified value of the output voltage of the second voltage converter 34. That is, the cutoff circuit unit 36 cuts off the voltage supply to the first voltage conversion unit 33 in a state where the input voltage input to the second voltage conversion unit 34 is higher than the output voltage of the first voltage conversion unit 33. Thus, the output circuit unit 35 is supplied with a voltage having a specified value from at least one of the first voltage conversion unit 33 and the second voltage conversion unit 34, and outputs the output circuit unit 35 when the cutoff circuit unit 36 cuts off the voltage. The voltage output from is never temporarily reduced to zero. In addition, since the voltage input to the first voltage conversion unit 33 is cut off by the cutoff circuit unit 36, the first voltage conversion unit 33 is protected from being damaged by an overvoltage.

  FIGS. 4A and 4B are graphs showing a temporal change in the voltage of each unit of the power supply circuit unit 3 when the rotation speed of the main shaft 10 increases from zero to near the maximum speed and then decreases to zero. 32, (b) is the input voltage to the first voltage converter 33, (c) is the output voltage of the first voltage converter 33, and (d) is the output voltage of the second voltage converter 34. And (e) shows the output voltage of the output circuit unit 35, respectively.

As shown in FIG. 4 (a), the output voltage of the rectifier circuit 32 rises with the rotation speed of the spindle 10 from time t ₀ to time t _4, then it becomes zero at time t _8. Voltage input to the first voltage converter 33, as shown in FIG. 4 (b), but to the time t ₃ increases with increasing output voltage of the rectifier circuit 32, the output of the rectifier circuit 32 at time t ₃ When the voltage reaches a predetermined value (V ₁ ), the voltage is cut off by the cutoff circuit unit 36 and becomes zero. When the output voltage of the rectifier circuit 32 becomes a predetermined value (V ₁₎ following at time t _5, the voltage blocking is released by the cutoff circuit 36, the voltage input to the first voltage conversion unit 33 is a rectifier circuit 32 It becomes almost equal to the output voltage.

The output voltage of the first voltage converter 33, the voltage input is blocked by the blocking circuit 36 in FIG. 4 (c), the stand up prescribed value at time t ₁ (V _2), and the time t ₃ And zero. Further, Standing output voltage of the first voltage converter 33, rising again when the output voltage of the rectifier circuit 32 at time t ₅ is equal to or less than a predetermined value (V _1), at time t ₇ the decrease in the output voltage of the rectifier circuit 32 It will be the prescribed value (V ₂ ) until it falls. This predetermined value (V ₁ ) is a value higher than the specified value (V ₂ ) of the output voltage of the first voltage converter 33 and the second voltage converter 34.

The output voltage of the second voltage converter 34, as shown in FIG. 4 (d), at time t ₂ when the output voltage of the rectifier circuit 32 becomes a prescribed value of the output voltage of the second voltage converter 34 (V ₂₎ stand up. The second voltage converter 34, until the output voltage of the rectifier circuit 32 at time t ₆ is the prescribed value of the output voltage of the second voltage converter 34 (V _2), and outputs a voltage of specified value (V ₂₎ . Between the time _{t 2} to time _{t 3,} and between the time _{t 5} to time _{t 6,} the first voltage conversion unit 33 and the second voltage converter 34 outputs a voltage of both the specified value _{(V 2)} Overlap period.

From the output circuit unit 35, from the specified value (V ₂ ) of the output voltage of the first voltage conversion unit 33 and the second voltage conversion unit 34 over the period from time t ₁ to t _7, the first diode 351 and the second diode A voltage having a voltage value (V ₃ ) obtained by subtracting the voltage drop of 352 (for example, 0.7 V) is output. This voltage value (V ₃ ) is a value suitable as the operating voltage of the electronic components such as the CPU 41 in the control circuit unit 4, for example, 3.3 V.

  FIGS. 5A and 5B are schematic diagrams illustrating a configuration example of the pump unit 7. The pump unit 7 is operated by an electric signal supplied from the control circuit unit 4, and discharges fine droplets D of the lubricating oil L from the discharge port 71. In the present embodiment, the pump section 7 has two discharge ports 71 (see FIG. 1), and each rolling element 123 of the pair of rolling bearings 12 sandwiching the lubricating oil supply device 2 from each discharge port 71. , A fine droplet D of the lubricating oil L is discharged. 5A and 5B show one discharge port 71 and a structure for discharging the droplet D from the discharge port 71. FIG.

  The pump unit 7 has a pump body 70 provided with a discharge port 71 and a piezo element 72 whose peripheral edge is fixed to the pump body 70. The piezo element 72 has a characteristic that its shape changes when a voltage is applied. In the present embodiment, the piezo element 72 is curved by application of a voltage, and the lubricating oil L introduced into the pump body 70 is compressed, and a part of the lubricating oil L jumps out of the discharge port 71 as a droplet D. The pump unit 7 is configured.

  The control circuit unit 4 supplies a pulse-like electric signal to the pump unit 7 via the electric wire 24. When the voltage of the electric signal is applied, the piezo element 72 deforms at the rising edge of the pulse and causes the droplet D to fly out. FIG. 5A shows a state when a voltage is not applied to the piezo element 72, and FIG. 5B shows a state when a voltage is applied to the piezo element 72.

  The CPU 41 of the control circuit unit 4 controls the pump unit 7 according to, for example, the rotation speed of the main shaft 10 so that the higher the rotation speed, the higher the frequency at which the droplet D jumps out. Specifically, the frequency of the pulse signal is increased. As a result, wear of the rolling bearing 12 can be suppressed, and seizure and the like can be prevented. The CPU 41 can detect the rotation speed of the main shaft 10 by communicating with, for example, a host controller that controls the motor unit 13. When the sensor circuit section 5 has a magnetic field sensor for detecting the rotation speed of the main shaft 10, the rotation speed of the main shaft 10 may be detected based on a detection signal of the magnetic field sensor.

  Further, the CPU 41 controls the pump unit 7 so that the larger the vibration detected by the vibration sensor 51 of the sensor circuit unit 5 is, the more frequently the droplet D is ejected. Thereby, vibration of the spindle device 1 due to insufficient lubrication of the rolling bearing 12 can be suppressed.

  A part of the DC power supplied from the power supply circuit unit 3 to the control circuit unit 4 is stored in the battery 45, and the electronic components such as the CPU 41 use the power stored in the battery 45 even when the spindle 10 is stopped. It is possible to work. The control circuit unit 4 communicates with the host controller even when the spindle 10 is stopped, and sends information on the detected value of the vibration intensity by the vibration sensor 51 and the detected value of the temperature by the temperature sensor 52 to the host controller, for example. Send.

(Operation and effect of the embodiment)
According to the power generating device 9 according to the embodiment described above, even if the rotation speed of the main shaft 10 with respect to the housing 11 fluctuates greatly, it is possible to stably generate a predetermined DC voltage and supply it to the control circuit unit 4. It becomes possible. Then, the lubricating oil L can be appropriately supplied to the rolling bearing 12. In particular, in the present embodiment, the power supply circuit unit 3 includes the first voltage conversion unit 33 as a voltage conversion unit for boosting and the second voltage conversion unit 34 as a voltage conversion unit for step-down. In a wide range of the rotation speed of the main shaft 10, it is possible to supply the control circuit unit 4 with DC power having an appropriate voltage value for operating electronic components such as the CPU 41.

(Note)
As described above, the present invention has been described based on the embodiments, but these embodiments do not limit the invention according to the claims. Also, it should be noted that not all combinations of the features described in the embodiments are necessarily indispensable for means for solving the problems of the invention.

  Further, the present invention can be appropriately modified and implemented without departing from the spirit thereof. For example, in the above embodiment, the case where the power generation device 9 is applied to the main shaft device 1 has been described. However, the application of the power generation device according to the present invention is not limited to the main shaft device, and can be applied to various devices. is there. Further, in the above embodiment, a plurality of magnets (first magnet 81 and second magnet 82) are attached to the rotating member (main shaft 10), and a coil (power generation coil 31) is attached to the fixed member (housing 11). Although the description has been given of the case where the rotation is performed, the coil may be mounted on the rotating member, and a plurality of magnets may be mounted on the fixed member. In this case, DC power of a predetermined voltage value can be supplied to an electronic component or the like that rotates together with the rotating member.

  Further, in the above embodiment, the case where the pump unit 7 has two discharge ports 71 has been described, but the pump unit 7 may have one discharge port 71. In this case, lubricating oil is supplied to one of the pair of rolling bearings 12 sandwiching the lubricating oil supply device 2. The one rolling bearing 12 is desirably the one of the pair of rolling bearings 12, 12 which has a larger load when the main shaft 10 rotates. In addition, the configuration of the pump unit 7 is not limited to the configuration using the piezo element. It may be supplied.

  Further, in the above-described embodiment, a case has been described in which the first voltage converter 33 for boosting and the second voltage converter 34 for step-down are provided as the plurality of voltage converters. A third voltage converter for step-up or step-down may be further provided.

1. Spindle device 10 Spindle (rotating member)
11 ... housing (fixing member)
31 ... Generating coil (coil)
32 rectifier circuit 33 first voltage converter (voltage converter for boosting)
34: second voltage converter (voltage converter for step-down)
35 output circuit section 36 cutoff circuit section 4 control circuit section 81 first magnet 82 second magnet 9 power generation device L lubricant oil

Claims (5)

A power generating device that generates a predetermined DC voltage by rotation of a rotating member with respect to a fixed member,
A magnet attached to one of the fixed member and the rotating member,
A coil attached to the other of the fixed member and the rotating member, and the magnetic flux of the magnet interlinks,
A rectifier circuit that converts an AC voltage generated by the coil into a DC voltage,
A plurality of voltage converters capable of boosting or stepping down an input voltage supplied from the rectifier circuit to a specified voltage and outputting the voltage;
An output circuit unit for selectively outputting any one of the output voltages of the plurality of voltage conversion units,
The plurality of voltage conversion units are different from each other in a range of an input voltage required to output the voltage of the specified value.
Power generator. The voltage conversion unit includes a voltage conversion unit for boosting the input voltage and outputting the voltage, and a voltage conversion unit for stepping down the input voltage and outputting the voltage.
The power generator according to claim 1. When the output voltage of the rectifier circuit is equal to or higher than a predetermined value, the rectifier circuit further includes a cutoff circuit unit that cuts off voltage supply from the rectifier circuit to the voltage converter for boosting.
The power generator according to claim 2. The output circuit unit is configured to output a higher one of an output voltage of the step-down voltage converter and an output voltage of the step-up voltage converter,
The cutoff circuit unit cuts off voltage supply to the boosting voltage converter in a state where an input voltage input to the step-down voltage converter is higher than an output voltage of the boosting voltage converter.
The power generator according to claim 3. A power generator according to any one of claims 1 to 4,
A control circuit unit using a DC voltage generated by the power generation device as a power supply,
A spindle as the rotating member;
A pump that is controlled by the control circuit unit and that discharges lubricating oil that facilitates rotation of the spindle;
Spindle device equipped with

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