JP2019074040A - Trochoid pump, lubricating oil supply unit, and bearing device - Google Patents

Abstract

To allow operation of a pump to be monitored.SOLUTION: A pump 29 comprises an inner rotor 104, an outer rotor 105 arranged outside the inner rotor 104, magnetism generating bodies 111-115 whose positions are changed in association with rotation of the outer rotor 105, a pump case 106 internally housing the outer rotor 105, and a magnetic pole detecting sensor 9 arranged on the pump case 106 to detect a magnetic field from the magnetism generating bodies 111-115. Preferably, the magnetism generating bodies 111-115 are embedded in an outer peripheral surface of the outer rotor 105, and the outer rotor 105 and the pump case 106 are made of resin.SELECTED DRAWING: Figure 14

Description

  The present invention relates to a trochoid pump, a lubricating oil supply unit and a bearing device, and more particularly to a trochoid pump and a lubricating oil supply unit for supplying lubricating oil to the inside of a bearing, and a bearing device including them.

  Although the lubrication system of the spindle for a machine tool is generally an air oil lubrication system, it requires an external oil tank and additional equipment for air supply. On the other hand, grease-lubricated bearings do not require any external equipment, but have a long service life. An example of a lubricating oil supply unit for extending the lubricating life of a grease-lubricated bearing is disclosed in JP-A-2016-153669 (Patent Document 1).

JP, 2016-153669, A

  The above lubricating oil supply unit is intended to extend the lubricating life of the bearing with a micro pump by replenishing the same lubricating oil as the base oil of grease to the inside of the bearing, but if the lubricating oil supply unit fails, the lubricating oil is replenished Ceases and the bearings are broken. For this reason, in Unexamined-Japanese-Patent No. 2016-153669, it is discriminate | determined whether lubricating oil was discharged by measuring the temperature in a bearing immediately after lubricating oil supply.

  However, it is necessary to supply a large amount of lubricating oil to check discharge by the temperature change in the bearing immediately after the lubricating oil is supplied, and the amount of supply per one operation is very small Since the rise is gradual, it is difficult to reliably catch the failure of the micro pump due to the temperature change in the bearing.

  Moreover, in the above-mentioned lubricating oil supply unit, the drive of the micro pump is controlled only by the time in the microcomputer, and there is also a problem that stable quantitative supply can not be performed against the viscosity change due to the type of lubricating oil and ambient temperature. .

  The present invention has been made to solve the problems as described above, and its object is to monitor the operation of a micro pump which is a major cause of unit failure and to determine the soundness of a lubricating oil supply unit. It is another object of the present invention to provide a trochoid pump, a lubricating oil supply unit and a bearing device which can perform stable supply against various fluctuation factors.

  The present invention, in summary, is a trochoid pump, which accommodates an inner rotor, an outer rotor disposed outside the inner rotor, a magnetism member whose position changes with the rotation of the outer rotor, and an outer rotor. A case and a magnetic pole detection sensor which is installed in the case and detects a magnetic field from a magnetizing member are provided.

Preferably, the magnetizing member is embedded in the outer peripheral surface of the outer rotor.
Preferably, the outer rotor and the case are made of resin.

  According to another aspect of the present invention, there is provided a trochoid pump according to any one of the above, a container for containing lubricating oil sucked by the trochoid pump, and a control device for monitoring the operating state of the trochoid pump upon receiving an output of a magnetic pole detection sensor. It is a lubricating oil supply unit provided.

  Preferably, the trochoid pump further comprises a motor for driving the inner rotor. The control device reports an abnormality of the trochoid pump when the output of the magnetic pole detection sensor indicates that the outer rotor is not rotating even though the drive signal is output to the motor.

  Preferably, the trochoid pump further comprises a motor for driving the inner rotor. The control device controls the discharge amount of the lubricating oil from the trochoid pump by driving the motor based on the output of the magnetic pole detection sensor.

  In another aspect, the present invention is a bearing device comprising any one of the above-described lubricating oil supply units.

  According to the present invention, the operation state of the micro pump can be easily monitored, and early detection of a failure and control of the lubricating oil discharge amount become possible.

It is a cross-sectional schematic diagram which shows an example of the mechanical apparatus which concerns on this embodiment. It is a cross-sectional schematic diagram of the mechanical apparatus shown in FIG. It is a plane schematic diagram of the external unit 70 attached to the mechanical apparatus shown in FIG. It is a block diagram for demonstrating the structure of the electric circuit of the principal part of a lubricating oil supply unit. It is a block diagram for demonstrating the structure of the external unit in a lubricating oil supply unit. It is a schematic diagram which shows the whole lubricating oil supply unit 20 provided adjacent to a bearing apparatus. It is a cross-sectional schematic diagram in line segment VII-VII of FIG. It is a cross-sectional schematic diagram in line segment VIII-VIII of FIG. It is a cross-sectional schematic diagram in line segment IX-IX of FIG. It is a figure which shows the structure of lubricating oil supply unit 20A which deform | transformed the electric power generation part. It is a figure which shows the structural example of the pump 29. As shown in FIG. It is a figure which shows the structure of the trochoid pump part 29A. It is a figure showing operation of a trochoid pump. It is a figure which shows the structure of the trochoid pump part used by this Embodiment. It is the figure which expanded and showed magnetic pole detection sensor vicinity of a trochoid pump part. FIG. 6 is a perspective view of an outer rotor 105. FIG. 10 is a perspective view of a pump case 106. It is a figure which shows the signal waveform output from a magnetic pole detection sensor, when an outer rotor rotates. It is a flowchart for demonstrating discharge control of lubricating oil. FIG. 5 is a basic waveform diagram for illustrating supply timing of lubricating oil. It is a flowchart which shows the detail of the first discharge process performed by step S5. It is a flowchart which shows the detail of the normal discharge process performed by step S6.

  Hereinafter, embodiments of the present invention will be described based on the drawings. In the following drawings, the same or corresponding parts have the same reference characters allotted and description thereof will not be repeated.

[Overview]
In the present embodiment, one of the features is that the lubricating oil supply unit 20 mounted on the bearing is configured to be able to monitor the operating state of the micro pump. Hereinafter, the configuration of the mechanical device incorporating the bearing, the configuration of the lubricating oil supply unit mounted on the bearing, and the configuration and control of the micro pump in the lubricating oil supply unit will be described in order.

[Configuration of machinery]
The configuration of a spindle for a machine tool, which is an example of a mechanical device to which the bearing device according to the present embodiment is applied, will be described with reference to FIGS. 1 to 3.

  FIG. 1 is a schematic cross-sectional view showing an example of a mechanical device according to the present embodiment. FIG. 2 is a schematic cross-sectional view of the mechanical device shown in FIG.

  With reference to FIGS. 1 and 2, the spindle 50 for a machine tool according to the present embodiment includes a rotating shaft 51, a spindle housing 52 disposed so as to surround the periphery of the rotating shaft 51, and an outer periphery of the spindle housing 52. It includes an outer circumferential housing 53 disposed, and a bearing device rotatably holding the rotation shaft 51 with respect to the spindle housing 52.

  Two bearing devices are disposed on the outer periphery of the rotating shaft 51. The inner ring 14 and the inner ring spacer 34 of the bearing in the bearing device are fitted and fixed to the side surface of the rotating shaft 51. Further, the outer ring 13 and the outer ring spacer 33 of the bearing are fitted and fixed to the inner peripheral surface of the spindle housing 52. In addition, although it may replace with fitting fixation and adhere and fix, in the case of adhesion fixation, an epoxy resin etc. can be used suitably.

  The bearing is an angular ball bearing, and includes an inner ring 14, an outer ring 13, and rolling elements 15 which are balls disposed between the inner ring 14 and the outer ring 13.

  A lubricating oil supply unit 20 is disposed between the inner ring spacer 34 and the outer ring spacer 33 disposed adjacent to the bearings. Further, another spacer is fitted and fixed to the rotating shaft 51 and the spindle housing 52 between the two bearings (the opposite side to the side on which the lubricating oil supply unit is disposed), and the inner ring 14 and the outer ring 13 It is hit.

  As shown in FIG. 2, the lubricating oil supply unit 20 includes a power generation unit 25 disposed along a circumferential direction in an annular housing, a power supply circuit 26 including a storage unit, a control circuit 27, and a pump drive. It includes a circuit 28, a pump 29, and a lubricating oil tank 30 for holding lubricating oil. The detailed configuration of the bearing device including the lubricating oil supply unit 20 will be described later.

  A through hole which penetrates the housing body 21 (see FIG. 7), the outer ring spacer 33, the spindle housing 52 and the outer peripheral housing 53 is formed in a region facing the control circuit 27 of the lubricating oil supply unit. At the outer peripheral end of the through hole, a flat portion is provided on the surface of the outer peripheral housing 53, and the pedestal 57 and the external unit 70 are disposed on the flat portion. An output substrate 56 is disposed on the pedestal 57.

  The control circuit 27 of the lubricating oil supply unit 20 is connected to the light emitting element 54. The output substrate 56 is connected to the light receiving element 55. For example, the light emitting element 54 is mounted on the control substrate on which the control circuit 27 is formed, and the light receiving element 55 is mounted on the output substrate 56.

  The light emitting element 54 and the light receiving element 55 are disposed to face each other across the through hole so that the light emitted from the light emitting element 54 is received by the light receiving element 55 through the through hole. That is, the light emitting element 54 and the light receiving element 55 are arranged such that the optical axis of the light emitted from the light emitting element 54 penetrates the inside of the through hole. The light transmitted / received between the light emitting element 54 and the light receiving element 55 may have any wavelength, and is, for example, infrared light (infrared ray). That is, the light emitting element 54 is provided, for example, using infrared light as a carrier wave so as to emit light toward the light receiving element 55 on which a signal wave including data on the supply condition of lubricating oil described later is superimposed. For example, an infrared light emitting diode is used as the light emitting element 54. For example, a photodiode is used as light receiving element 55.

  Since the light emitting element 54 functions as a transmitting unit that transmits a signal from the control circuit 27 to the external unit 70, the light emitting element 54 is described as the transmitting unit 54 in the block diagrams of FIGS. 4 and 5 later. Further, since the light receiving element 55 functions as a receiving unit that receives a signal from the transmitting unit, the light receiving element 55 is described as the receiving unit 55 in the block diagrams of FIGS. 4 and 5 later. The transmitting unit 54 and the receiving unit 55 may use not only infrared light but also other light, and may use radio waves.

  FIG. 3 is a schematic plan view of the external unit 70 attached to the mechanical device shown in FIG. Referring to FIGS. 2 and 3, the cover member 58 is fixed to the pedestal 57 so as to cover the output substrate 56 disposed on the pedestal 57. On the output substrate 56, a battery 60, which is a power supply for driving the circuit of the output substrate 56, and a storage unit 59 are disposed. As battery 60, a coin battery or a button battery can be used, for example. It is desirable to use a lithium ion battery as the battery 60, but another battery such as a nickel hydrogen battery may be used. A holder for fixing such a battery 60 is disposed on the surface of the output substrate 56. In addition, as the storage unit 59, for example, a holding unit (slot) for connecting and fixing a card-type external storage medium and an external storage medium detachably fixed to the holding unit can be used. As the external storage medium, any conventionally known storage medium such as a memory card can be used.

  The cover member 58 is formed with a U-shaped elongated hole (a hole for disposing the fixing bolt) so that the cover member 58 can be removed from the pedestal 57 simply by loosening the fixing bolt which is a connecting member with the pedestal 57. Replacement of the battery 60 and the external storage medium can be performed with the cover member 58 removed from the pedestal 57.

  The output substrate 56 sealed by the pedestal 57 and the cover member 58 constitutes the main part of the external unit. The pedestal 57 and the cover member 58 may have any waterproof structure in order to prevent the entry of coolant and the like used in processing using the processing machine spindle. As the waterproof structure, for example, packing, O-ring, caulking, resin molding or the like can be used.

  In addition, it is preferable that the cover member 58 use a transparent material so that the display content of the below-mentioned display part 71 can be visually recognized.

[Configuration of Lubricating Oil Supply Unit]
Details of the bearing device and the lubricating oil supply unit used in the mechanical device shown in FIG. 1 will be described with reference to FIGS.

  First, the configuration of the electric circuit of the lubricating oil supply unit installed on the machine tool spindle 50 will be described below mainly with reference to FIGS. 4 and 5.

  FIG. 4 is a block diagram for explaining the configuration of the electric circuit of the main part of the lubricating oil supply unit. FIG. 5 is a block diagram for explaining the configuration of the external unit in the lubricating oil supply unit.

  4 and 5, the lubricating oil supply unit includes a power generation unit 25, a power supply circuit 26, a control circuit 27, a magnetic pole detection sensor 9, a drive unit 90, a pump drive circuit 28, and a resistor 94. And.

  The power generation unit 25 generates power by the temperature difference generated between the inner ring and the outer ring of the bearing. The power supply circuit 26 boosts the voltage of the power generation unit 25, the power storage unit 86 stores the electric energy generated by the power generation unit 25 and passes through the boost converter 82, and boosts the voltage of the power storage unit 86 to load. And a boost converter 85 for supplying the

  The electric power stored in the storage unit 86 is supplied to the pump drive circuit 28 by microcomputer control or the like. When the pump 29 is driven by the pump drive circuit, lubricating oil is discharged from the nozzle of the pump 29 into the bearing.

  The control circuit 27 is a control unit for controlling the operation of the pump 29 via the pump drive circuit 28. The control circuit 27 is connected to a program storage unit in which the control program is held and the program storage unit, and executes a control program. (Including microcomputers). The control circuit 27 can preset the supply start timing and supply timing (interval) of the lubricating oil to the bearing 11 (FIG. 7). The control circuit 27 also determines the driving time of the pump 29 for supplying the lubricating oil, the supply amount of the lubricating oil, and the like based on the output of the magnetic pole detection sensor 9. And by maintaining the supply state of the lubricating oil in this way, it is possible to extend the lubricating life of the bearing device.

  More specifically, control circuit 27 includes a data processor 27a and a comparator 27b. The data processing device 27a includes an A / D converter 27d for taking in the value of the voltage VC as data, and a memory 27c for non-volatilely storing a state flag described later, the number of discharges and the number of discharges. The A / D converter 27 d and the memory 27 c may be incorporated in the data processing device 27 a or may be provided outside the data processing device 27 a.

  The comparator 27b outputs an interrupt signal when it detects that the voltage VC has reached a predetermined voltage. When receiving an interrupt signal from comparator 27b, data processing device 27a is activated from the sleep state and discharges the electric energy of power storage unit 86 using pump drive circuit 28 or resistor 94. At this time, the data processing device 27a controls the pump drive circuit 28 to drive the pump drive circuit 28 to supply the lubricating oil to the inside of the bearing after the discharge using the resistance 94 is performed a predetermined number of times. By doing this, the lubricant oil is supplied at an appropriate time interval. Details of the above control will be described later using a flowchart.

  The drive unit 90 includes switches 91 and 92 so that one of the pump drive circuit 28 and the resistor 94 can be energized. The drive unit 90 and the pump drive circuit 28 may be integrated into one.

  Referring to FIG. 5, external unit 70 receives data Sout relating to the supply state of lubricating oil from transmission unit 54 on control circuit 27 via reception unit 55, and receives data between operation unit 56a and operation unit 56a. And a display unit 71 that can be viewed from the outside, and a battery 60 that supplies a power supply voltage to the calculation unit 56a, the storage unit 59, and the display unit 71.

  The storage unit 59 stores data on the supply state of the lubricating oil transmitted from the control circuit 27. As data, the supply timing of lubricating oil, the supply interval of lubricating oil, the number of discharges, the number of remaining discharges, and the voltage (voltage VC) in the power supply circuit (specifically, power storage unit 86) when operating the pump 29 etc. Temperature around the inner ring or the outer ring.

  Arbitrary timing can be adopted as the timing at which this data is transmitted from control circuit 27 to external unit 70. For example, the storage unit of control circuit 27 (memory 27c included in data processing device 27a or memory 27c is independent) When the storage element or the like provided in the control circuit 27 becomes full of data, the data may be transferred from the control circuit 27 to the external unit 70. Alternatively, a part of the discarded power at the time of discharge in the lubricant oil supply timing basic waveform diagram of FIG. 20 may be allocated for data transfer and synchronized with the discharge timing.

  Arithmetic unit 56a causes display unit 71 to display information related to the supply of lubricating oil indicated by signal Sout. For example, as described later, even if the pump drive signal is sent, if the magnetic pole detection sensor 9 does not indicate the operation of the pump, the computing unit 56a displays a display indicating that the lubricating oil supply is abnormal. Display on 71

  Alternatively, the data stored in the storage unit 59 may be transmitted to a relay station or a computer in a management room using the wireless transmission unit 72. In this way, the condition of the lubricating oil supply unit (such as the power generation state and the operating state of the pump 29) can be confirmed on the external computer.

  FIG. 6 is a schematic view showing the entire lubricating oil supply unit 20 provided adjacent to the bearing device. 7 is a schematic cross-sectional view taken along line VII-VII in FIG. FIG. 8 is a schematic cross-sectional view taken along line VIII-VIII in FIG. FIG. 9 is a schematic cross-sectional view taken along line IX-IX of FIG.

  Referring to FIGS. 7 and 8, bearing device 10 includes a bearing 11 and a lubricating oil supply unit 20. As a bearing device, the bearing 11 and the lubricating oil supply unit 20 may be integrated.

  The lubricating oil supply unit 20 is incorporated between the outer ring spacer 33 and the inner ring spacer 34 that are butted against one end of the bearing 11 in the axial direction. The bearing device 10 is used by being incorporated, for example, between a rotating shaft of a mechanical device and a housing.

  The bearing 11 includes, for example, an inner ring 14 that is a bearing ring on the rotation side, an outer ring 13 that is on the fixed side, for example, a plurality of rolling elements 15 interposed between the inner ring 14 and the outer ring 13, and a plurality of rolling elements 15 And a seal member disposed on the outer peripheral side of the holder 16. Although an angular ball bearing is illustrated in the present embodiment, for example, a deep groove ball bearing or a cylindrical roller bearing can also be used as the bearing 11.

  Grease is sealed in the bearing 11 in advance. The seal member is disposed at an end opposite to the side where the outer ring spacer 33 and the like are disposed.

  An inner ring spacer 34 and an outer ring spacer 33 form a spacer, and the inner ring spacer 34 abuts on one end face of the inner ring 14. The outer ring spacer 33 is abutted against one end face of the outer ring 13.

  The lubricating oil supply unit 20 includes, as shown in FIG. 6, a power generation unit 25, a power supply circuit 26, a control circuit 27, a pump drive circuit 28, a pump 29, and a lubricating oil tank 30 disposed in an annular housing. . The lubricating oil tank 30 stores lubricating oil of the same type as the base oil of the grease sealed in the bearing 11. The power generation unit 25, the power supply circuit 26, the control circuit 27, the pump drive circuit 28, the pump 29, and the lubricating oil tank 30 are arranged in the circumferential direction in the housing main body 21.

  The power generation unit 25 is connected to the power supply circuit 26, the power supply circuit 26 is connected to the control circuit 27, and the control circuit 27 is connected to the pump drive circuit 28. The pump drive circuit 28 is a circuit for operating the pump 29 such as a micro pump. The pump 29 is connected to a suction tube 31 connected to a bag of the lubricating oil tank 30, and a discharge tube 32 for supplying lubricating oil from the pump 29 to the inside of the bearing 11. As shown in FIG. 7, a nozzle 37 is connected to the tip of the discharge tube 32 (the end opposite to the root connected to the pump 29). The tip end portion of the nozzle 37 extends to the inside of the bearing 11 (a position adjacent to the rolling element 15, for example, between the stationary race and the rotational race of the bearing 11). The inner diameter of the nozzle hole of the nozzle 37 is appropriately set according to the relationship between the surface tension and the discharge amount caused by the viscosity of the base oil.

  As the power generation unit 25 of the lubricating oil supply unit 20, for example, a thermoelectric element (Peltier element) that generates power by the Seebeck effect can be used. Specifically, as shown in FIG. 6, the power generation unit 25 includes a heat sink 23a connected to the outer ring spacer 33, a heat sink 23b disposed to face the inner ring spacer 34, a heat sink 23a, and a heat sink 23b. And a thermoelectric element 24 fixed in close contact with the heat sinks 23a and 23b.

  Here, when a rolling bearing device is used as the bearing device 10 as shown in FIG. 6, the temperature of the inner ring 14 and the outer ring 13 rises due to the frictional heat with the rolling element 15 (see FIG. 7). Since the outer ring 13 is usually incorporated into the housing of the device, it is dissipated by heat conduction. Therefore, a temperature difference occurs between the inner ring 14 and the outer ring 13 (the temperature of the inner ring 14 is higher than the temperature of the outer ring 13). The temperature is conducted to each heat sink 23a, 23b.

  The heat sinks 23a and 23b are disposed so as to penetrate the inner peripheral surface and the outer peripheral surface of the housing body 21, respectively. Therefore, temperature is applied to both end faces of the thermoelectric element 24 disposed between the heat sink 23a connected to the outer ring 13 via the outer ring spacer 33 and the heat sink 23b located on the inner ring spacer 34 side (inner ring 14 side) There is a difference. Therefore, the thermoelectric element 24 can generate power by the Seebeck effect. The low temperature side of the thermoelectric element 24 may be in direct contact with the inner circumferential surface of the outer ring spacer 33.

  The heat transfer (heat dissipation) effect is enhanced by bringing the close contact surface of the heat sink 23 a on the outer ring side into close contact with the curvature of the inner diameter of the outer ring spacer 33. On the other hand, the heat sink 23b on the inner ring side is not in contact with the inner ring spacer 34. If possible, it is desirable to increase the surface area of the inner peripheral surface of the heat sink 23b on the inner ring side. Also, thermal conductivity (and adhesion) between the inner circumferential surface of the outer ring spacer 33 and the outer circumferential surface of the heat sink 23a, between the heat sink 23a and the thermoelectric element 24, and between the thermoelectric element 24 and the inner ring side heat sink 23b. It is good to apply a heat release grease etc. in order to raise The heat dissipating grease is generally composed mainly of silicon. The heat sinks 23a and 23b use a metal having a high thermal conductivity. For example, gold, silver, copper and the like can be mentioned, but copper is generally used in terms of cost. In addition, the copper alloy which has copper as a main component may be used. Further, as a processing method, sintering, forging, casting and the like are advantageous in cost.

  By using such a power generation unit 25, there is no need to supply power to the lubricating oil supply unit from the outside, so there is no need to attach a wire for supplying power from the outside to the machine tool spindle 50.

  The charge generated (generated) by the power generation unit 25 is stored in the power supply circuit 26. Specifically, the charge is stored in storage unit 86 such as a storage battery or a capacitor included in power supply circuit 26 shown in FIG. It is preferable to use an electric double layer capacitor (capacitor) as the capacitor.

  The pump 29 is controlled by a control circuit 27 via a pump drive circuit 28. The pump 29 sucks the lubricating oil in the lubricating oil tank 30 from the suction tube 31 and supplies the suctioned lubricating oil to the inside of the bearing 11 through the discharge tube 32 and the nozzle 37.

  The annular housing of the lubricating oil supply unit 20, as shown in FIG. 7, closes the opening of the housing main body 21 with a U-shaped housing main body 21 whose surface opposite to the bearing 11 is open. The cover 22 is detachably attached to the housing body 21. The housing body 21 and the lid 22 are preferably formed of a thermoplastic resin such as PPS.

  The lid 22 of the housing may be fixed to the housing body 21 by a screw 39 (see FIG. 9). By fixing the lid 22 to the housing body 21, the inside of the housing surrounded by the housing body 21 and the lid 22 can be sealed. Note that the lid 22 can be removed by removing the screw 39 from the tap hole 35 to which the screw 39 is fixed. In this way, the lubricating oil can be replenished to the lubricating oil tank 30 housed in the housing main body 21 without removing the entire lubricating oil supply unit 20 from the bearing device 10.

  The outer peripheral surface of the housing main body 21 is fixed to the inner peripheral surface of the outer ring spacer 33. The housing body 21 (i.e., the lubricating oil supply unit 20) may be fixed to the stationary wheel of the bearing 11. A gap 36 is formed between the housing body 21 and the inner ring spacer 34.

  FIG. 10 is a diagram showing the configuration of a lubricant oil supply unit 20A in which the power generation unit is deformed. The lubricating oil supply unit 20A shown in FIG. 10 may have the configuration of the power generation unit 195 such that the low temperature side of the thermoelectric element 125 is in direct contact with the inner circumferential surface of the outer ring spacer 33. In the heat conductor 196, the thermoelectric element 125 is further closely fixed to the inner circumferential surface of the outer ring spacer 33 by being pressed in the outer diameter direction by the repulsive force of the compression coil spring 98.

  Although not shown, the power supply circuit 26, the control circuit 27, the pump drive circuit 28, the pump 29, the lubricating oil tank 30, and the like in FIG. Will be accommodated.

[Micro pump configuration and control]
It is conceivable to use a trochoidal pump for the micro pump because of the size of the lubricating oil supply unit. FIG. 11 is a view showing a structural example of the pump 29. As shown in FIG.

  Pump 29 includes a trochoid pump portion 29A and a motor 29B. The trochoid pump portion 29A includes a pump case 106, an outer rotor 105, an inner rotor 104, and pump lids 101 and 107. The rotation shaft of the motor 29 </ b> B is coupled to the inner rotor 104. The pump lid 101 is formed with a suction port connected to the suction tube 31 and a discharge port connected to the discharge tube 32.

  FIG. 12 is a view showing the structure of the trochoid pump portion 29A. FIG. 13 is a view showing the operation of the trochoid pump.

  The material of the trochoid pump portion 29A is resin. The motor 29B is rotated by the current supplied from the pump drive circuit 28 operated by the power stored in the storage unit 86, and the inner rotor 104 is rotated. The inner rotor 104 and the outer rotor 105 are in contact with and engaged with each other at a plurality of places. Inside the trochoid pump portion 29A, a plurality of spaces (for example, five spaces) divided by respective contact portions between the inner rotor 104 and the outer rotor 105 are formed.

  When the inner rotor 104 makes one rotation as in θ0 to θ6, the outer rotor 105 rotates about half in the same direction by meshing with the inner rotor 104. The rotation of the inner rotor 104 and the outer rotor 105 changes the volumes of the plurality of spaces.

  The volume of the space formed by the difference in the number of teeth of the outer gear of the inner rotor 104 and the inner gear of the outer rotor 105 changes, and suction and discharge of the lubricating oil become possible.

  Trocoid pumps without valve mechanism have poor sealability, and depending on the positional relationship between the lubricating oil tank, micro pump and nozzle, there may be minor leakage of lubricating oil, backflow of air, and factors that inhibit long-term stable lubricating oil supply It can be For this reason, it is preferable to provide a check valve (check valve) in the discharge tube 32 connected to the discharge port of the micro pump. Since the check valve does not open unless a constant discharge pressure is generated by the micro pump, it is possible to prevent a slight leak of the lubricating oil and at the same time prevent the backflow of air.

  In the trochoid pump having such a configuration, as shown in the vicinity of θ0 in FIG. 13, when the volume of one space becomes the smallest, the distance between the inner rotor 104 and the outer rotor 105 in the space is, for example, May be smaller than the outer diameter of the non-lubricating oil etc.) The pump 29 is controlled by the control circuit 27 via a pump drive circuit 28.

  If foreign matter in the lubricating oil is caught between the inner rotor 104 and the outer rotor 105 whose distance is reduced, the inner rotor 104 and the outer rotor 105 may not be able to rotate in the trochoid pump portion 29A. In such a case, it is preferable that the control circuit 27 can detect an abnormality and notify it to the outside.

  In addition, the lubricating oil changes its viscosity with temperature, and the torque required to drive the pump 29 also fluctuates. Therefore, even if the pump 29 is driven for a fixed time, for example, the discharge amount of the lubricating oil from the pump 29 may vary.

  The trochoid pump portion 29A functions as a pump by the rotation of the outer rotor 105 following the rotation of the inner rotor 104. Therefore, if it is possible to monitor the number of rotations and the rotation angle of the outer rotor 105, It is possible to grasp the state and the discharge amount.

  FIG. 14 is a diagram showing the configuration of a trochoidal pump used in the present embodiment. FIG. 15 is an enlarged view of the vicinity of the magnetic pole detection sensor of the trochoid pump portion. FIG. 16 is a perspective view of the outer rotor 105. FIG. FIG. 17 is a perspective view of the pump case 106. FIG.

  Referring to FIGS. 14 to 17, on the outer peripheral side surface of outer rotor 105, magnetizing members 111 to 115 of the same number as the number of teeth of outer rotor 105 are embedded. The magnetic pole detection sensor 9 is installed outside the pump case 106. Permanent magnets can be used as the magnetizing members 111 to 115. Further, as the magnetic pole detection sensor 9, a Hall IC, a Hall element or the like can be used. The number of magnetizing members may not be the same as the number of teeth of the outer rotor 105, and may be one.

  FIG. 18 is a diagram showing a signal waveform output from the magnetic pole detection sensor when the outer rotor rotates. When the outer rotor rotates at a constant speed, the magnetic pole detection sensor 9 periodically repeats on / off. Therefore, by counting the number of output pulses of the magnetic pole detection sensor, the control circuit 27 can grasp the rotational speed and the rotational angle of the outer rotor.

[Supply operation and error detection of lubricating oil supply unit]
FIG. 19 is a flow chart for explaining the discharge control of the lubricating oil. FIG. 20 is a basic waveform diagram for illustrating the supply timing of the lubricating oil. In FIG. 20, the vertical axis represents the voltage of the storage unit, the horizontal axis represents time, and the time variation (charging and discharging state) of the voltage VC of the storage unit is shown as a waveform.

  In FIG. 19, control circuit 27 in the sleep mode monitors voltage VC of power storage unit 86 in step S1, and determines whether voltage VC is equal to or higher than a predetermined voltage (for example, 2.5 V). If the voltage VC is lower than 2.5 V, the process of step S1 is repeated until the voltage VC reaches 2.5 V as it is. The voltage VC is gradually increased by the power generated by the power generation unit 25.

  When the voltage VC becomes 2.5 V or more in step S1, the control circuit 27 recovers from the sleep mode in step S2. Then, in step S3, the four pieces of information stored in the non-volatile memory are read out. The four pieces of information to be read out are the state flag, the number of initial discharges, the number of normal discharges, and the number of discharges. The state flag is a flag indicating whether the discharge to be performed from now is the first discharge or the normal discharge. The first discharge is discharge of lubricating oil performed in anticipation of the time when the grease initially filled in the bearing device has run out of base oil. This is carried out about 10,000 hours after the start of use because it is carried out waiting for the base oil depletion of the new grease. On the other hand, normal discharge is the second and subsequent discharges when the first discharge has been executed, and is performed about every 20 hours. As shown in FIG. 20, control circuit 27 determines these intervals by counting the number of times of charge and discharge of power storage unit 86.

  Subsequently, in step S4, the control circuit 27 determines whether the read state flag indicates the first ejection or the normal ejection. When the status flag indicates the first discharge in step S4, the first discharge process is performed in step S5. On the other hand, when the status flag indicates normal discharge in step S4, normal discharge processing is executed in step S6.

  When the discharge process is performed in step S5 or step S6, the control circuit 27 shifts to the sleep mode in step S7, and maintains the sleep mode again until the voltage VC reaches a predetermined voltage or more in step S1.

  FIG. 21 is a flowchart showing the details of the first discharge process performed in step S5. When the first discharge process is started, first in step S11, the control circuit 27 determines whether the number of times of first discharge read from the memory is equal to or more than a set value. The set value is set to a number corresponding to 10000 hours, as shown in the waveform diagram of FIG. In addition, 10000 hours is an example, and a setting value is suitably adjusted with a rotational speed, a grease type, etc.

  In step S11, if the number of first discharges is less than the set value (NO in S11), control circuit 27 conducts switch 92 in FIG. 4 so as to discharge the electrical energy stored in power storage unit 86 in step S12. Let Then, in step S13, the control circuit 27 adds 1 to the number of first discharges, and stores the number of first discharges in the non-volatile memory. Thereafter, the process returns to the flow of FIG. 20 in step S23, and the control circuit 27 shifts to the sleep mode.

  On the other hand, if the number of initial discharges is equal to or greater than the set value in step S11 (YES in S11), the control circuit 27 causes the switch 91 in FIG. 4 to conduct so as to operate the pump 29 in step S14. Then, the control circuit 27 counts the number of output pulses of the magnetic pole detection sensor 9 in step S15, and continues driving the pump 29 in step S16 until the count number becomes equal to or more than the set value. However, if the output of the magnetic pole detection sensor 9 indicates that the outer rotor is not rotating even if the drive signal is output to the motor in step S16, the control circuit 27 uses the transmission unit to determine that the trochoid pump is abnormal. Is notified to the external unit, and the process ends. When the count number becomes equal to or more than the set value in step S16 (YES in S16), the control circuit 27 turns off the switch 91 so as to stop the pump 29 in step S17.

  Then, in step S18, the control circuit 27 adds 1 to the number of times of ejection and stores the result in the memory 27c. Further, in step S19, the control circuit 27 changes the state flag from the first state to the normal state, and transmits the number of ejections and the number of remaining ejections to the external unit 70 by infrared rays in step S20. Thereafter, control circuit 27 causes switch 92 to conduct so as to discharge surplus electrical energy from power storage unit 86, returns the process to the flowchart of FIG. 20 in step S23, and shifts to the sleep mode.

  FIG. 22 is a flowchart showing the details of the normal discharge process performed in step S6. The normal discharge process shown in FIG. 22 is different from the first discharge process shown in FIG. 21 in that the processes of steps S11, S13, and S19 are replaced with the processes of steps S11A, S13A, and S19A, respectively. The other processes are the same, so only the differences will be described.

  When the normal discharge process is started, first, in step S11A, the control circuit 27 determines whether the number of times of normal discharge read from the memory 27c is equal to or more than a set value. The set value is set to a number corresponding to 20 hours as shown in the waveform diagram of FIG. In addition, 20 hours is an example, and a setting value is suitably adjusted with a rotational speed, a grease type, etc.

  If the number of normal discharges is less than the set value in step S11A (NO in S11A), control circuit 27 discharges the electrical energy stored in power storage unit 86 in step S12, and the normal number of discharges is 1 in step S13A. After the addition, the process returns to the flow of FIG. 20 in step S23, and the control circuit 27 shifts to the sleep mode.

  On the other hand, if the number of normal discharges is equal to or greater than the set value in step S11A (YES in S11A), the control circuit 27 executes the operation and stop of the pump 29 in the same manner as the first time in steps S14 to S18. Further, the control circuit 27 resets the number of normal discharges to zero in step S19A, and transmits the number of discharges and the number of remaining discharges to the external unit by infrared rays in step S20. Thereafter, control circuit 27 causes switch 92 to conduct so as to discharge surplus electrical energy from power storage unit 86, returns the process to the flowchart of FIG. 20 in step S23, and shifts to the sleep mode.

  The configuration of the embodiment described above will be summarized. Referring to FIGS. 1 and 2, the lubricating oil supply unit 20 is mounted on the inner peripheral surface of the outer ring spacer 33. Inside the lubricating oil supply unit 20, a lubricating oil tank 30 storing lubricating oil of the same type as the base oil of the bearing-enclosed grease is provided. The lubricating oil in the lubricating oil tank 30 is supplied by the pump 29 to the inside of the bearing. Electric power for driving and controlling the pump 29 is generated by the thermoelectric element 24. The electric power generated by the thermoelectric element 24 is stored in the storage unit 86 of FIG. 4.

  As shown in FIG. 14 to FIG. 17, the magnetizing members 111 to 115 are embedded in the outer peripheral portion of the outer rotor 105 in the trochoid pump portion 29A constituting the pump 29. A magnetic pole detection sensor 9 is provided outside the pump case 106 of the trochoid pump portion 29A for detecting the magnetic poles of the magnetizing members 111 to 115 embedded in the outer peripheral portion of the outer rotor 105, and the output signal from the magnetic pole detection sensor 9 is a control circuit 27. Is input to The control circuit 27 is provided with a transmission unit 54 for transmitting information to the outside of the spindle, and an external unit 70 outside the spindle receives an infrared signal from the control circuit 27 and information on the lubricating oil supply unit Can be displayed.

  With the above-described configuration, by setting in advance the timing to supply (replenish) the same kind of lubricating oil as the grease base oil to the inside of the grease lubricated bearing to the control circuit 27, the timing to supply after the start, the supply amount, etc. The lubricating life of the lubricated bearing can be extended. At this time, the control circuit 27 takes in the signal of the magnetic pole detection sensor 9 and counts the number of ON / OFF of the signal waveform to monitor the number of rotations or the rotation angle of the outer rotor 105 of the trochoid pump portion 29A. Is possible. That is, the discharge amount can be converted from the rotation speed, the rotation angle, and the volume of the space formed by the difference in the number of teeth of the outer rotor 105 and the inner rotor 104, which can not be achieved by the conventional control method using only the motor drive time It becomes possible to eliminate the instability of the discharge amount due to the viscosity change that occurs due to the difference between the base oil and the temperature that were present.

  Further, when the rotation can not be detected, the defect information is transmitted to the external unit 70 by infrared communication because the defect of the pump 29 is suspected, and the display on the display unit 71 or the wireless transmission unit 72 is further performed. Can communicate defect information to the user through communication.

  Although the embodiments of the present invention have been described above, various modifications of the above-described embodiments are possible. Further, the scope of the present invention is not limited to the above-described embodiment. The scope of the present invention is defined by the terms of the claims, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  Reference Signs List 9 magnetic pole detection sensor, 10 bearing device, 11 bearing, 13 outer ring, 14 inner ring, 15 rolling element, 16 cage, 20, 20A lubricating oil supply unit, 21 housing main body, 22 lid, 23a, 23b heat sink, 24, 125 thermoelectric Element, 25, 195 power generation unit, 26 power supply circuit, 27 control circuit, 27a data processing device, 27b comparator, 27c memory, 27d converter, 28 pump drive circuit, 29 pump, 29A trochoid pump unit, 29B motor, 30 lubricating oil tank , 31 suction tube, 32 discharge tube, 33 outer ring spacer, 34 inner ring spacer, 35 tap hole, 36 gap, 37 nozzle, 39 screw, 50 spindle for machine tool, 51 rotation shaft, 52 spindle housing, 53 outer peripheral housing, 54 transmitter (from Elements), 55 receiving unit (light receiving element), 56 output substrate, 56a computing unit, 57 pedestal, 58 cover member, 59 storage unit, 60 battery, 70 external unit, 71 display unit, 72 wireless transmitting unit, 82, 85 boost voltage Converter, 86 power storage unit, 90 drive unit, 91, 92 switch, 94 resistance, 98 compression coil spring, 101 pump lid, 104 inner rotor, 105 outer rotor, 106 pump case, 111 to 115 magnetized body, 196 heat conductor.

Claims (7)

Inner rotor,
An outer rotor disposed outside the inner rotor;
A magnetizing member whose position changes with the rotation of the outer rotor;
A case for housing the outer rotor therein;
And a magnetic pole detection sensor disposed in the case for detecting a magnetic field from the magnetizer.   The trochoid pump according to claim 1, wherein the magnetizing body is embedded in an outer peripheral surface of the outer rotor.   The trochoid pump according to claim 1, wherein the outer rotor and the case are made of resin. A trochoidal pump according to any one of claims 1 to 3;
A container for containing lubricating oil drawn by the trochoid pump;
A control device for receiving an output of the magnetic pole detection sensor and monitoring an operation state of the trochoid pump. The trochoid pump further comprises a motor for driving the inner rotor,
5. The controller according to claim 4, wherein when the output of the magnetic pole detection sensor indicates that the outer rotor is not rotating even when the drive signal is output to the motor, the control device reports an abnormality of the trochoid pump. Lubricant supply unit as described. The trochoid pump further comprises a motor for driving the inner rotor,
The lubricant oil supply unit according to claim 4, wherein the control device controls the amount of discharge of the lubricant oil from the trochoid pump by driving the motor based on an output of the magnetic pole detection sensor.   The bearing apparatus provided with the lubricating oil supply unit of any one of Claims 4-6.

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