JP2016153669A - Lubricant supply unit and bearing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lubricant supply unit capable of detecting supply abnormality of lubricant.SOLUTION: A lubricant supply unit includes: a lubricant tank 30 holding lubricant; a pump 29 configured to supply lubricant from the lubricant tank 30 to the inside of a bearing; a temperature sensor 9 configured to detect a temperature of the bearing or a member adjacent to the bearing; and a data processing device 27a configured to control an operation of the pump 29, and detect whether temperature change is detected by the temperature sensor 9 in synchronization with timing of instructing the pump 29 to supply lubricant.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a lubricating oil supply unit, and more particularly to a lubricating oil supply unit that supplies lubricating oil inside a bearing and a bearing device including the same.

  2. Description of the Related Art Conventionally, a rolling bearing device in which an oil supply unit is incorporated in a rolling bearing is known. In a bearing device disclosed in Japanese Patent Laying-Open No. 2005-180629 (Patent Document 1), grease is sealed inside a rolling bearing, and the same type of lubricating oil as the base oil of this grease is adjacent to the rolling bearing. It is accommodated in a spacer, and lubricating oil in the spacer is replenished and supplied to the inside of the rolling bearing by capillary action.

  In addition, the bearing device disclosed in Japanese Patent Application Laid-Open No. 2014-37879 (Patent Document 2) lubricates the bearing by intermittently operating the pump from a lubricating oil tank disposed in a spacer adjacent to the bearing. It is said that oil can be supplied stably for a long time.

JP 2005-180629 A JP 2014-37879 A

  In the apparatus disclosed in Japanese Patent Application Laid-Open No. 2005-180629 described above, grease is sealed in advance in the bearing and lubrication is performed. At the same time, the base oil of grease contained in the spacer is always supplied into the bearing. Therefore, the supply of the lubricating oil tends to be excessive, and the consumption of the base oil (lubricating oil) in the spacer is fast, so it is difficult to stably supply the lubricating oil to the bearing for a long period of time.

  Further, in the device disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 2014-37879, it is considered that the supply of lubricating oil can be carried out for a longer period of time than the device disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 2005-180629. Therefore, it is not possible to confirm the supply state of the lubricating oil. Therefore, even if there is a failure in the supply of lubricating oil due to factors such as malfunction of the pump or running out of lubricating oil, etc., the problem of such a supply failure of the lubricating oil should be grasped until an abnormality occurs in the operation of the bearing. Is difficult. For this reason, in order to operate the bearing device stably for a long period of time, it has been difficult to take measures such as detecting an abnormality of the bearing device at an early stage and performing maintenance.

  In particular, even if the pump is driven, a failure in which the lubricating oil is not normally supplied is assumed. Therefore, it is desirable to detect that the lubricating oil is actually supplied to the bearing portion.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a lubricating oil supply unit capable of detecting an abnormal supply of lubricating oil.

  In summary, the present invention provides a lubricating oil supply unit comprising: a holding portion that holds lubricating oil; a supply portion that supplies lubricating oil from the holding portion to the inside of the bearing; and a temperature of a bearing or a member adjacent to the bearing. A temperature detection unit for detecting, and a control unit for controlling the operation of the supply unit and detecting whether or not a temperature change is detected by the temperature detection unit in synchronization with a timing at which the supply unit is instructed to supply the lubricant. Is provided.

  Preferably, when the temperature change is not detected, the control unit outputs a signal indicating that the lubricating oil is not normally supplied.

More preferably, the temperature change is a temperature increase of a predetermined value or more.
Preferably, the lubricating oil supply unit further includes a transmission unit that transmits a signal indicating a temperature change detection state from the control unit to the external unit. The external unit is provided at a position distant from the bearing and visible from the outside of the device in which the bearing is built.

  Preferably, the lubricating oil supply unit further includes a power generation unit that generates electric power for operating the supply unit, and a power storage unit that is charged by the electric power generated by the power generation unit. The controller performs discharging from the power storage unit when power storage exceeds the determination value. The discharge includes a first discharge that is executed by operating the supply unit and a second discharge that is executed without operating the supply unit. The control unit compares the temperature change detected by the temperature detection unit during the first discharge with the temperature change detected by the temperature detection unit during the second discharge.

  More preferably, the lubricating oil supply unit further includes a transmission unit that transmits a signal indicating the comparison result of the temperature change from the control unit to the external unit. The external unit is provided at a position distant from the bearing and visible from the outside of the device in which the bearing is built.

  More preferably, the transmission unit transmits a signal to the external unit using infrared rays or radio waves.

  Preferably, the lubricating oil supply unit is located away from the transmission unit that transmits a signal indicating information on temperature change from the control unit and the bearing, and is visible from the outside of the device in which the bearing is incorporated. And an external unit to be provided. The external unit includes a reception unit that receives a signal from the transmission unit, and a display unit that displays information based on the signal received by the reception unit.

  Preferably, the lubricating oil supply unit is located away from the transmission unit that transmits a signal indicating information on temperature change from the control unit and the bearing, and is visible from the outside of the device in which the bearing is incorporated. And an external unit to be provided. The external unit receives a signal from the transmission unit, and transmits information based on the received signal to at least one of the relay base and the management room by radio.

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

  According to the present invention, it is possible to detect at an early stage that a lubricating oil supply abnormality has occurred, and it is possible to detect an abnormality in the bearing device at an early stage and perform maintenance.

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 machine 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 the 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 an expansion schematic diagram of the area | region X of FIG. It is a basic waveform diagram for explaining the supply timing of the lubricating oil. It is the wave form diagram which showed the temperature change of the bearing at the time of normal. It is a wave form diagram which showed the temperature change of the bearing at the time of lubricating oil supply abnormality. 5 is a flowchart for explaining pump drive control and abnormality determination control executed by the data processing device of FIG. 4.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated.

<Configuration of mechanical device>
With reference to FIGS. 1-3, the structure of the spindle for machine tools which is an example of the mechanical apparatus to which the bearing apparatus which concerns on this embodiment is applied is demonstrated.

  FIG. 1 is a schematic cross-sectional view illustrating 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, a machine tool spindle 50 according to this embodiment includes a rotation shaft 51, a spindle housing 52 arranged to surround the rotation shaft 51, and an outer periphery of the spindle housing 52. It includes an outer peripheral housing 53 that is arranged, and a bearing device that rotatably holds the rotating shaft 51 with respect to the spindle housing 52.

  Two bearing devices are arranged 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 of the bearing and the outer ring spacer 33 are fitted and fixed to the inner peripheral surface of the spindle housing 52. The bearing including the inner ring 14, the outer ring 13, and the rolling elements 15 that are balls disposed between the inner ring 14 and the outer ring 13 is an angular ball bearing.

  The lubricating oil supply unit 20 is disposed between the inner ring spacer 34 and the outer ring spacer 33 that are disposed adjacent to the bearing. In addition, between the two bearings (on the side opposite to the side where the lubricating oil supply unit is disposed), other spacers are fitted and fixed to the rotating shaft 51 and the spindle housing 52, and are connected to the inner ring 14 and the outer ring 13. It has been hit.

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

  A through hole that penetrates the housing main 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. A flat portion is provided on the surface of the outer peripheral housing 53 at the outer peripheral side end portion of the through hole, and a pedestal 57 is disposed on the flat portion. An output board 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 board on which the control circuit 27 is formed, and the light receiving element 55 is mounted on the output board 56.

  The light emitting element 54 and the light receiving element 55 are disposed to face each other with the through hole interposed therebetween so that 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 so that the optical axis of the light emitted from the light emitting element 54 passes through the through hole. The light transmitted and received between the light emitting element 54 and the light receiving element 55 may have an arbitrary wavelength, but is, for example, infrared light (infrared light). In other words, the light-emitting element 54 is provided so that, for example, infrared light is used as a carrier wave and light on which a signal wave including data related to the supply state of lubricating oil, which will be described later, is superimposed can be emitted toward the light-receiving element 55. As the light emitting element 54, for example, an infrared light emitting diode is used. As the light receiving element 55, for example, a photodiode is used.

  Since the light emitting element 54 functions as a transmission unit that transmits a signal from the control circuit 27 to the external unit 70, the light emitting element 54 is described as the transmission unit 54 in the block diagrams of FIGS. Since the light receiving element 55 functions as a receiving unit that receives a signal from the transmitting unit, it is described as the receiving unit 55 in the block diagrams of FIGS. The transmission unit 54 and the reception unit 55 are not limited to infrared light, and may use other light, or may use radio waves.

  FIG. 3 is a schematic plan view of the external unit 70 attached to the machine apparatus shown in FIG. With reference to FIGS. 2 and 3, the cover member 58 is fixed to the pedestal 57 so as to cover the output board 56 disposed on the pedestal 57. On the output board 56, a battery 60 as a power source for driving the circuit of the output board 56 and a storage unit 59 are arranged. As the battery 60, for example, a coin battery or a button battery can be used. Although it is desirable to use a lithium ion battery as the battery 60, other batteries such as a nickel metal hydride battery may be used. A holder for fixing the battery 60 is disposed on the surface of the output substrate 56. 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 fixed to the holding unit in a removable manner 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 in which the fixing bolt is disposed) so that the cover member 58 can be removed from the pedestal 57 simply by loosening the fixing bolt as 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 board 56 sealed by the pedestal 57 and the cover member 58 constitutes a main part of the external unit. The pedestal 57 and the cover member 58 can be added with an arbitrary waterproof structure in order to prevent intrusion of coolant or the like used during processing using the processing machine spindle. As the waterproof structure, for example, packing, O-ring, caulking, resin mold or the like can be used.

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

  The configuration of the electric circuit of the lubricating oil supply unit installed on the above-described machine tool spindle 50 will be described below mainly with reference to FIGS.

  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 temperature sensor 9, a drive unit 90, a pump drive circuit 28, and a resistor 94.

  The power generation unit 25 generates power based on a 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 storage unit 25, the power storage unit 86 that stores the electric energy generated by the power generation unit 25 via the boost converter 82, and the voltage of the power storage unit 86. And a boost converter 85 that supplies the load to the load.

  The control circuit 27 is a control unit for controlling the operation of the pump 29 via the drive circuit 28, and includes a program storage unit that stores a control program and an arithmetic unit that is connected to the program storage unit and executes the control program (Microcomputer). The control circuit 27 sets in advance the supply start timing of lubricant oil to the bearing 11 (FIG. 7), the supply timing (interval), the driving time of the pump 29 for supplying the lubricant, the supply amount of the lubricant, and the like. Can do. And the lubrication life of a bearing apparatus can be extended by maintaining the supply state of lubricating oil appropriately in this way.

  More specifically, the control circuit 27 includes a data processing device 27a and a comparator 27b. The data processing device 27a includes an A / D converter 27d for capturing the output of the temperature sensor 9 and the value of the voltage VC as data, and a memory 27c for storing data relating to temperature changes monitored by the temperature sensor 9 in a nonvolatile manner. Including. The A / D converter 27d and the memory 27c may be built in the data processing device 27a, or may be provided outside the data processing device 27a.

  When the comparator 27b detects that the voltage VC has reached a predetermined voltage, it outputs an interrupt signal. When the data processing device 27a receives an interrupt signal from the comparator 27b, the data processing device 27a starts from the sleep state and discharges the electrical energy of the power storage unit 86 using the pump drive circuit 28 or the resistor 94. At this time, the data processing device 27a performs control so that the pump drive circuit 28 is driven after the discharge using the resistor 94 is performed a predetermined number of times to supply the lubricating oil into the bearing. By doing so, the lubricating oil is supplied at an appropriate time interval.

  The drive unit 90 includes switches 91 and 92 so that either 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 combined into one.

  The pump drive circuit 28 may include, for example, an arbitrary sensor (a bearing temperature sensor, a bearing rotation sensor, a lubricant remaining amount sensor, a lubricant temperature sensor, etc.). Signals from these sensors may be input to a calculation unit (microcomputer) of the drive circuit 28, and the pump 29 may be automatically controlled in accordance with the temperature of the bearing 11 and its rotation state to adjust the supply amount of the lubricating oil.

  In addition, the data processing device 27a receives at least one of the inner ring temperature Ti1, the inner ring side heat conductor temperature Ti2, and the outer ring side heat conductor temperature To from the temperature sensor 9 after activation, and these temperature changes cause the pump drive circuit 28 to change. It is analyzed whether or not it is synchronized with the timing of the used lubricating oil supply. The data processing device 27a causes the transmission unit 54 to output a signal Sout indicating the analysis result. Details of the above control will be described later using a flowchart.

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

  The storage unit 59 stores data relating to the lubricant supply state transmitted from the control circuit 27. The data includes lubricating oil supply timing, lubricating oil supply interval, voltage (power storage voltage) data in the power supply circuit (specifically, the power storage unit) when the pump 29, etc. are operated, Temperature.

  Any timing can be adopted as the timing at which this data is transmitted from the control circuit 27 to the external unit 70. For example, the storage unit of the control circuit 27 (independent of the memory 27c or the memory 27c included in the data processing device 27a) can be used. The data may be transferred from the control circuit 27 to the external unit 70 when the storage element provided in the control circuit 27 becomes full of data.

  The calculation unit 56a causes the display unit 71 to display information related to the supply of the lubricating oil indicated by the signal Sout. For example, as described later, when the temperature change synchronized with the supply timing of the lubricating oil is not observed in the bearing or its peripheral members, the calculation unit 56a displays a display indicating that an abnormality has occurred in the supply of the lubricating oil. Display on the unit 71.

  In addition, the data stored in the storage unit 59 may be transmitted to a relay base or a computer in a management room using the wireless transmission unit 72. In this way, it is possible to check the state of the lubricating oil supply unit (power generation state, operation state of the pump 29, etc.) on the external computer.

<Details of configuration of bearing device and lubricating oil supply unit>
With reference to FIGS. 6-10, the detail of the bearing apparatus and lubricating oil supply unit which are used for the machine apparatus shown in the said FIG. 1 is demonstrated.

  FIG. 6 is a schematic view showing the entire lubricating oil supply unit 20 provided adjacent to the bearing device. FIG. 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 sectional view taken along line IX-IX in FIG.

  With reference to FIGS. 7 and 8, the bearing device 10 includes a bearing 11 and a lubricating oil supply unit 20. Note that the bearing 11 and the lubricating oil supply unit 20 may be integrated as a bearing device.

  The lubricating oil supply unit 20 is incorporated between an outer ring spacer 33 and an inner ring spacer 34 that are abutted 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 and a housing of a mechanical device.

  The bearing 11 includes, for example, an inner ring 14 which is a rotating raceway ring, a fixed outer ring 13, a plurality of rolling elements 15 interposed between the inner ring 14 and the outer ring 13, and a plurality of rolling elements 15. Is held at a constant interval, and a seal member disposed on the outer peripheral side of the retainer 16 is included. An angular ball bearing is illustrated in the present embodiment, but as the bearing 11, for example, a deep groove ball bearing or a cylindrical roller bearing can be used.

  The bearing 11 is filled with desired grease in advance. The seal member is disposed at the end opposite to the side where the outer ring spacer 33 or the like is disposed.

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

  As shown in FIG. 6, the lubricating oil supply unit 20 includes a power generation unit 25, a power supply circuit 26, a control circuit 27, a drive circuit 28, a pump 29, a lubricating oil tank arranged in an annular housing in the circumferential direction. 30 is included. The lubricating oil tank 30 stores the same type of lubricating oil 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 drive circuit 28, the pump 29, and the lubricating oil tank 30 are arranged in the circumferential direction in the housing body 21. The power generation unit 25 is connected to a power circuit 26, the power circuit 26 is connected to a control circuit 27, and the control circuit 27 is connected to a drive circuit 28. The drive circuit 28 is a circuit for operating a pump 29 such as a micropump. A suction tube 31 connected to the bag body 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 are connected to the pump 29. A nozzle 37 is connected to the distal end of the discharge tube 32 (the end opposite to the base connected to the pump 29), as shown in FIG. The tip of the nozzle 37 extends to the inside of the bearing 11 (position adjacent to the rolling element 15, for example, between the bearing ring on the fixed side and the bearing ring on the rotating side of the bearing 11). Note that the inner diameter of the nozzle hole of the nozzle 37 is appropriately set according to the relationship between the surface tension resulting from the viscosity of the base oil and the discharge amount.

  As the power generation unit 25 of the lubricating oil supply unit 20, for example, a unit that generates power by the Seebeck effect can be used. Specifically, as illustrated in FIG. 6, the power generation unit 25 includes a heat conductor 23 a connected to the outer ring spacer 33, a heat conductor 23 b disposed to face the inner ring spacer 34, and heat conduction. The thermoelectric element 24 (element utilizing the Seebeck effect of the Peltier element) is disposed so as to connect between the body 23a and the heat conductor 23b, and is closely fixed to the heat conductors 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 frictional heat with the rolling elements 15 (see FIG. 7). Normally, the outer ring 13 is dissipated by heat conduction because it is incorporated in the housing of the device. 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 conductor 23a, 23b.

  The heat conductors 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, a thermoelectric element disposed between the heat conductor 23a (heat sink) connected to the outer ring 13 via the outer ring spacer 33 and the heat conductor 23b located on the inner ring spacer 34 side (inner ring 14 side). A temperature difference occurs between both end faces of 24. For this reason, the thermoelectric element 24 can generate electric power by the Seebeck effect.

  By using such a power generation unit 25, it is not necessary to supply power to the lubricating oil supply unit from the outside, and therefore it is not necessary to attach an electric wire for supplying power to the machine tool spindle 50 from the outside.

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

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

  As shown in FIG. 7, the annular housing of the lubricating oil supply unit 20 has a U-shaped housing body 21 whose surface opposite to the bearing 11 is open, and the opening of the housing body 21 is closed. The lid body 22 is detachably attached to the housing body 21.

  The housing lid 22 may be fixed to the housing body 21 with screws 39 (see FIG. 9). By fixing the lid body 22 to the housing body 21, the inside of the housing surrounded by the housing body 21 and the lid body 22 can be sealed. 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 body 21 without removing the entire lubricating oil supply unit 20 from the bearing device 10.

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

  FIG. 10 is an enlarged schematic view of region X in FIG. The bag body of the lubricating oil tank 30 is provided with a suction tube 31 connected to the pump 29. When the bag body of the lubricating oil tank 30 is formed by heat welding, the suction tube 31 is sandwiched between the stacked resin sheets to form the bag body and heat-welded. In this way, the suction tube 31 can be integrated with the bag.

  The suction tube 31 provided in the bag body of the lubricating oil tank 30 may be detachably connected to the pump 29. By making the suction tube 31 detachable from the pump 29, when the remaining amount of lubricating oil in the lubricating oil tank 30 runs out, the suction tube 31 is removed from the pump 29 and lubricated from the suction tube 31 into the bag body. Oil can be replenished.

  Moreover, by making the bag body of the lubricating oil tank 30 removable with respect to the pump 29, a spare bag body filled with lubricating oil can be prepared and the bag body can be replaced. For example, when the lubricating oil in the used lubricating oil tank 30 runs out, remove the used lubricating oil tank 30 bag and replace it with a spare bag (a bag filled with lubricating oil). By doing so, the lubricating oil supply unit 20 can be replenished in a short time.

  The bearing device described above is an inner ring rotation. Further, although the rotation center is the horizontal axis, it may be the vertical axis.

<Lubricating oil supply unit supply operation and abnormality detection>
The lubricating oil supply unit described above improves the reliability and durability of the machine tool spindle 50 by periodically supplying lubricating oil to the bearing 11 (see FIG. 7).

  The driving timing of the pump 29 can be performed when the electric power generated in the power generation unit 25 is stored in the power storage unit 86 (for example, a capacitor) in the power supply circuit 26 and the voltage of the power storage unit reaches a certain voltage. is there. Furthermore, in order to extend the lubrication life of the bearing 11 filled with grease and to increase the time to maintenance, it is desirable to set the following intervals.

  FIG. 11 is a basic waveform diagram for explaining the supply timing of the lubricating oil. In FIG. 11, the vertical axis indicates the voltage of the power storage unit, the horizontal axis indicates time, and the time change (charge and discharge status) of the voltage VC of the power storage unit is shown as a waveform.

  When the voltage of the power storage unit reaches the voltage V2 necessary for driving the pump 29 (or reaches full charge), the pump 29 is driven by the electric power stored in the power storage unit at time t1.

  Further, as shown in FIG. 11, once the pump 29 is driven and a part of the discharge is performed, then the discharge by the resistance is further performed and the voltage of the power storage unit 86 is lowered to the voltage V1, and the charging operation is performed again. It is. As a result, the voltage VC of the power storage unit 86 reaches the voltage V2. However, if the pump 29 is driven each time the voltage reaches V2 to supply the lubricating oil into the bearing, the supply amount may be too large. Therefore, after driving the pump 29 once, the electric charge of the power storage unit 86 is discharged a predetermined number of times by the resistor 94 of FIG.

  Specifically, as shown in FIG. 11, after the pump 29 is driven once (time t1), charging and discharging are repeated eight times, and when the ninth full charge is reached (time t2 when the voltage V2 is reached). The driving interval of the pump 29 may be managed so as to repeat the cycle of driving the pump 29 in FIG. In order to control in this way, the number N of discharges is stored in the control circuit 27, and N is increased every time discharge is performed, and control is performed so that the pump 29 is driven when N = 9.

  In FIG. 11, the post-discharge voltage V1 at the time of driving the pump is lower than the post-discharge voltage V3 due to the resistor. In order to make it easy to observe the pump drive timing, the voltage V3 and the voltage V1 may be equal. Since the data processing device 27a in FIG. 4 performs the pump drive by itself, the pump drive timing can be known without referring to the voltage VC.

  The lubricating oil discharge time (amount) and interval (interval) can be determined in advance by programming the data processor 27a in the lubricating oil supply unit.

  When such basic control is executed, the temperature of the bearing is also monitored in the present embodiment. If the temperature changes in synchronization with the drive timing of the pump, it is determined that the lubricating oil has actually been discharged into the bearing. On the other hand, if the temperature does not change, the lubricating oil is not supplied. to decide.

  For example, a spindle for a machine tool or the like may be used to detect abnormal heat generation of the bearing by monitoring the temperature on the bearing outer ring side. When the lubrication performance inside the bearing is lowered, heat generation due to rolling friction of the rolling elements increases, and the temperature of the inner and outer rings becomes higher than that at normal time. Therefore, the temperature sensor 9 shown in FIG. 4 is often provided in the bearing.

  The temperature sensor 9 can be used to detect the supply of lubricating oil. If the amount of lubricating oil inside the bearing is greater than the amount that contributes to lubrication, the temperature of the inner and outer rings will be higher than when the amount of lubricating oil is appropriate due to the influence of stirring resistance caused by the rotation of rolling elements and cages. . Immediately after the lubricating oil is discharged into the bearing, such a temperature increase is observed.

  Therefore, in the present embodiment, the outer ring (or inner ring) temperature rise immediately after the lubricating oil is discharged into the bearing is recorded together with the time information, and is compared with the pre-programmed discharge interval to thereby obtain the outer ring (or inner ring). The supply history of the lubricating oil can be confirmed based on the temperature rise on the side and the time information.

  FIG. 12 is a waveform diagram showing changes in the temperature of the bearing during normal operation. FIG. 13 is a waveform diagram showing a change in the temperature of the bearing when the lubricating oil supply is abnormal. 12 and 13 show inner ring temperature Ti1, inner ring side heat conductor temperature Ti2, outer ring side heat conductor temperature To, and voltage VC of power storage unit 86.

  In FIG. 12, the temperatures Ti1, Ti2, and To rise in synchronization with the pump drive times t1A and t2A. Therefore, when such a waveform is observed, it can be seen that the lubricating oil is actually supplied into the bearing.

  On the other hand, in FIG. 13, there is no increase in the temperatures Ti1, Ti2, and To synchronized with the pump drive times t1B and t2B. Therefore, when such a waveform is observed, it can be seen that no lubricating oil is supplied into the bearing.

  FIG. 14 is a flowchart for explaining pump drive control and abnormality determination control executed by the data processing apparatus of FIG. The process of this flowchart is called from a predetermined main routine and executed.

  Referring to FIGS. 4 and 14, when the processing of this flowchart is started, in step S1, it is determined whether or not there is an interrupt signal from comparator 27b that is generated when voltage VC is 2.5 V or higher. If there is no interrupt signal in step S1, the data processing device 27a maintains the sleep state, and control is returned to the main routine in step S20.

  On the other hand, if an interrupt signal is input in step S1, the process proceeds to step S2, and the data processing device 27a wakes up.

  In step S3, the data processing device 27a reads the number N of discharges of the power storage unit 86 stored in the nonvolatile memory 27c. Subsequently, in step S4, the data processing device 27a determines whether or not the number of discharges N is less than a specified value. For example, in the example shown in FIG.

  If the number of discharges N is less than the specified value in step S4 (YES in S4), the process proceeds to step S5. In step S5, the number of ejections is read from the nonvolatile memory 27c. In step S <b> 6, the data processing device 27 a transmits the number of ejections and the remaining number of ejections to the external unit 70. In step S <b> 7, the data processing device 27 a discharges the electric charge of the power storage unit 86 by the resistor 94.

  Subsequently, in step S8, the data processing device 27a measures the bearing temperature (temperature T1) by the temperature sensor 9, and stores it in the memory 27c. In step S9, the data processing device 27a adds 1 to the number N of discharges, and writes the number N of discharges in the nonvolatile memory 27c in step S17.

  On the other hand, if the number of discharges N is greater than or equal to the specified value in step S4 (NO in S4), the process proceeds to step S10.

  In step S10, the data processing device 27a drives the pump drive circuit 28 to cause the pump 29 to discharge the lubricating oil. In step S <b> 11, the data processing device 27 a measures the bearing temperature (temperature T <b> 2) using the temperature sensor 9. In step S12, the temperature T1 stored in the memory 27c is read, and it is determined whether T2> T1. This determination may be made based on T2−T1> α. Here, α may be a value determined in advance in consideration of measurement error and the like.

  As described in FIGS. 12 and 13, if T2> T1, the lubricating oil is normally supplied to the bearing, and if there is no difference between T2 and T1, it can be determined that the lubricating oil has not been supplied to the bearing. .

  If T2> T1 is not satisfied in step S12 (NO in S12), the process proceeds to step S18, and the data processing device 27a transmits to the external unit 70 that an abnormality has occurred in the supply of lubricating oil. For example, the external unit 70 outputs a display indicating an abnormality to the display unit 71, or notifies the management room or the like of the abnormality by the wireless transmission unit 72. When the process of step S18 ends, the process proceeds to step S19.

  On the other hand, if T2> T1 is satisfied in step S12 (YES in S12), the process proceeds to step S13. In step S13, the number of discharges of the lubricating oil is added once, and in step S14, the number of discharges is written in the nonvolatile memory 27c. Subsequently, after the discharge is completed to the voltage V1 using the resistor 94 in step S15, the number of discharges is reset in step S16, and the reset number of discharges is written in the nonvolatile memory 27c in step S17.

  After the writing in step S17 is completed, the process proceeds to step S19. In step S19, the data processing device 27a shifts to the sleep state, and control is returned to the main routine in step S20.

  When the process proceeds to step S18, the temperature rise timing does not coincide with the pre-programmed discharge timing, so that the program is abnormal, the pump is operating abnormally, or the lubricating oil leaks in the tank. The discharge or suction tube is disconnected, the discharge port is clogged, or the capacitor is charged (accumulated). Although it is not easy to identify which of these abnormalities, as shown in FIG. 12 and FIG. 13, the abnormality of the program or the capacitor is detected by detecting the temperature together with the stored voltage VC of the power storage unit 86. Can be specified.

  The temperature comparison in step S12 is performed by the data processing device 27a, and the result is stored in the memory 27c. The stored information can be transmitted from the unit to the outside of the spindle using infrared communication, radio wave communication, or the like. An external unit 70 for receiving the above information is provided on the outer peripheral surface of the spindle and displayed on the liquid crystal screen of the display unit 71 or recorded on an external recording medium of the storage unit 59 and compared with an external computer or the like. The result and abnormality determination result can be confirmed.

  Although FIG. 12 and FIG. 13 do not show the temperature change of the bearing outer ring, the temperature change immediately after the lubricating oil is discharged can be confirmed in the bearing outer ring as well as the inner ring and the inner and outer ring side heat conductors. Accordingly, the temperature of the outer ring may be observed to determine whether or not lubricating oil is discharged.

  In the process of the flowchart of FIG. 14, the bearing temperature T1 immediately after discharging is recorded in the resistor 94, and the bearing temperature T2 immediately after the operation of the pump 29 is higher than the bearing temperature T2 immediately after the pump 29 is operated. The unit function was normal, and when there was no difference between T1 and T2, it was judged abnormal. Although an example has been described in which the temperature rises when the lubricating oil is discharged, the temperature may be lowered when the temperature of the lubricating oil to be supplied is low, such as when the lubricating oil is supplied from the outside. Therefore, even if the temperature change is not a temperature increase but a temperature decrease, the same determination can be made by checking whether or not the change is synchronized with the pump operation timing. Alternatively, the temperature may be constantly monitored, and it may be determined as abnormal if the temperature change timing and the pump operation timing are not in a predetermined relationship (not synchronized).

  Further, information may be transmitted from the external unit 70 outside the spindle to the relay base or the management room by the wireless transmitter 72 by wireless radio waves. The type of radio wave is not specified.

The present invention can also be applied to various rotating machines other than the machine tool spindle.
The lubricating oil supply unit shown in the present embodiment can accurately confirm that the lubricating oil has been discharged into the interior by confirming the temperature rise around the bearing (including the bearing). For this reason, the reliability of the lubricating oil supply unit is improved. Further, since it is possible to check the past discharge history and the number of possible future discharges, it is easy to understand the maintenance time of the unit. Furthermore, since the change over time of the bearing temperature is measured, the abnormal phenomenon of the bearing can be confirmed at an early stage.

Finally, referring to FIG. 4 again, the present embodiment will be generally described.
The lubricating oil supply unit according to the present embodiment includes a lubricating oil tank 30 that holds lubricating oil, a pump 29 that supplies lubricating oil from the lubricating oil tank 30 to the inside of the bearing, and the temperature of the bearing or a member adjacent to the bearing. The temperature sensor 9 detects the temperature and the data processing for controlling the operation of the pump 29 and detecting whether a temperature change is detected by the temperature sensor 9 in synchronism with the timing at which the pump 29 is instructed to supply the lubricant. Device 27a.

  Whether or not the temperature change is synchronized with the timing at which the pump 29 is instructed to supply the lubricating oil, a delay time until the temperature change occurs from the command is experimentally obtained in advance, If a temperature change occurs within a period that takes into account a time error or the like, it may be determined that they are synchronized.

  Preferably, when no temperature change is detected, the data processing device 27a causes the transmission unit 54 to output a signal Sout indicating that the lubricating oil is not normally supplied. Moreover, the temperature change to detect can be made into the temperature rise more than a predetermined value.

  Preferably, the lubricating oil supply unit further includes a transmission unit (light emitting element 54) that transmits a signal indicating the detection state of the temperature change from the data processing device 27a to the external unit 70. The external unit 70 is provided at a position distant from the bearing and visible from the outside of the device in which the bearing is built.

  Preferably, the lubricating oil supply unit further includes a power generation unit 25 that generates electric power for operating the pump 29, and a power storage unit 86 that is charged by the electric power generated by the power generation unit 25. The data processing device 27a performs discharging from the power storage unit 86 when the power storage unit 86 stores power exceeding the determination value. The discharge includes a first discharge that is performed by operating the pump 29 and a second discharge that is performed without operating the pump 29. The data processing device 27a compares the temperature change detected by the temperature sensor 9 during the first discharge with the temperature change detected by the temperature sensor 9 during the second discharge.

  More preferably, the lubricating oil supply unit further includes a transmission unit 54 that transmits a signal indicating the comparison result of the temperature change from the data processing device 27a to the external unit 70. The external unit 70 is provided at a position distant from the bearing and visible from the outside of the device in which the bearing is built.

  More preferably, the transmission unit transmits a signal to the external unit 70 using infrared rays or radio waves.

  Preferably, the lubricating oil supply unit is located away from the bearing and the transmission unit 54 that transmits a signal indicating information on temperature change from the data processing device 27a, and is visible from the outside of the device in which the bearing is incorporated. And an external unit 70 provided at various positions. The external unit 70 includes a receiving unit 55 that receives a signal from the transmitting unit 54 and a display unit 71 that displays information based on the signal received by the receiving unit 55.

  Preferably, the lubricating oil supply unit is located at a position away from the bearing and the transmission unit (light emitting element 54) that transmits a signal indicating information on a temperature change from the data processing device 27a, and the device in which the bearing is incorporated. And an external unit 70 provided at a position visible from the outside. The external unit 70 receives a signal from the transmission unit, and transmits information based on the received signal to at least one of the relay base and the management room by radio.

  Although the embodiment of the present invention has been described above, the above-described embodiment can be variously modified. 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.

  DESCRIPTION OF SYMBOLS 9 Temperature sensor, 10 Bearing apparatus, 11 Bearing, 13 Outer ring, 14 Inner ring, 15 Rolling body, 16 Cage, 20 Lubricating oil supply unit, 21 Housing body, 22 Lid body, 23a, 23b Thermal conductor, 24 Thermoelectric element, 25 Power generation unit, 26 Power supply circuit, 27 Control circuit, 27a Data processing device, 27b Comparator, 27c Non-volatile memory, 27d Converter, 28 Pump drive circuit, 29 Pump, 30 Lubricating oil tank, 31 Tube, 32 Discharge tube, 33 Between outer rings Seat, 34 Inner ring spacer, 35 Tap hole, 36 Clearance, 37 Nozzle, 39 Screw, 50 Spindle for machine tool, 51 Rotating shaft, 52 Spindle housing, 53 Outer housing, 54 Transmitter (light emitting element), 55 Receiver ( Light receiving element), 56 output board, 56a arithmetic unit, 57 units , 58 cover member, 59 storage unit, 60 battery, 70 an external unit, 71 display unit, 72 wireless transmission unit, 82 and 85 boost converter 86 power storage unit, 90 drive unit, 91 and 92 switches, 94 resistance.

Claims (11)

A holding part for holding lubricating oil;
A supply unit for supplying the lubricating oil from the holding unit to the inside of the bearing;
A temperature detector for detecting the temperature of the bearing or a member adjacent to the bearing;
A control unit that controls the operation of the supply unit and detects whether or not a temperature change is detected by the temperature detection unit in synchronization with a timing at which the supply unit is instructed to supply the lubricant. Lubricating oil supply unit.   2. The lubricating oil supply unit according to claim 1, wherein, when the temperature change is not detected, the control unit outputs a signal indicating that the lubricating oil is not normally supplied. 3.   The lubricating oil supply unit according to claim 2, wherein the temperature change is an increase in temperature equal to or higher than a predetermined value. A transmission unit for transmitting a signal indicating the detection status of the temperature change from the control unit to an external unit;
The lubricating oil supply unit according to claim 1, wherein the external unit is provided at a position distant from the bearing and visible from the outside of a device in which the bearing is built.   The lubricating oil supply unit according to claim 4, wherein the transmission unit transmits the signal to the external unit using infrared rays or radio waves. A power generation unit for generating electric power for operating the supply unit;
A power storage unit charged with electric power generated by the power generation unit,
The control unit performs discharging from the power storage unit when power storage exceeding a determination value is performed in the power storage unit,
The discharge includes a first discharge that is performed by operating the supply unit, and a second discharge that is performed without operating the supply unit,
2. The lubrication according to claim 1, wherein the control unit compares a temperature change detected by the temperature detection unit during the first discharge with a temperature change detected by the temperature detection unit during the second discharge. Oil supply unit. A transmission unit that transmits a signal indicating the comparison result of the temperature change from the control unit to an external unit;
The lubricating oil supply unit according to claim 6, wherein the external unit is provided at a position distant from the bearing and visible from the outside of a device in which the bearing is incorporated.   The lubricating oil supply unit according to claim 7, wherein the transmission unit transmits the signal to the external unit using infrared rays or radio waves. A transmission unit for transmitting a signal indicating information on the temperature change from the control unit;
An external unit provided at a position distant from the bearing and visible from the outside of the device in which the bearing is incorporated;
The external unit is
A receiver that receives the signal from the transmitter;
The lubricating oil supply unit according to claim 1, further comprising a display unit that displays information based on the signal received by the receiving unit. A transmission unit for transmitting a signal indicating information on the temperature change from the control unit;
An external unit provided at a position distant from the bearing and visible from the outside of the device in which the bearing is incorporated;
The lubricating oil supply unit according to claim 1, wherein the external unit receives the signal from the transmission unit, and transmits information based on the received signal to at least one of a relay base and a management room by radio.   A bearing device comprising the lubricating oil supply unit according to claim 1.

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