JP2004173407A - Eddy-current speed reducer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To detect any failure or operation abnormality with ease in an eddy-current speed reducer using electromagnets. <P>SOLUTION: The temperature of or in proximity to an electromagnetic coil is measured, or the value of a current passed through the electromagnetic coil is measured. The measured value is compared with a preset value, and any failure in the eddy-current speed reducer is determined based on the result of the comparison. For example, the eddy-current speed reducer comprises a braking unit which applies braking force to a rotating shaft and releases the application of braking force using electromagnetic fields produced by energization of the electromagnetic coil, a first temperature sensor 12 which detects the temperature of the electromagnetic coil, and a judgment unit which judges the presence or absence of any failure in the equipment based on the output of the first temperature sensor 12. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
[Industrial applications]
The present invention relates to an eddy current type speed reducer, and more particularly, to an eddy current type speed reducer having a structure in which braking or releasing is applied to a rotating shaft by energizing or de-energizing an electromagnetic coil.
[0002]
[Prior art]
Eddy current type reduction gears (hereinafter referred to as "retarders") can be roughly classified into a type using only a permanent magnet, a type using only an electromagnet, and a type including both a permanent magnet and an electromagnet ( 2002-272193). In a retarder using a permanent magnet, a magnet support ring provided with a plurality of permanent magnets on the outer periphery is arranged inside a stator case, and the braking force is switched by moving the magnet support ring. On the other hand, in a retarder using an electromagnet, an electromagnetic coil wound around an iron core is disposed close to a rotor, and braking or releasing of a rotating shaft (rotor) is performed by energizing or de-energizing the electromagnetic coil. Has become.
[0003]
[Problems to be solved by the invention]
In the conventional eddy current type speed reducer, even if the brake release command is output from the control device, current may be supplied to the coil due to control failure and the brake may remain in the brake state. Conversely, even if a braking command is output from the control device, there may be a case where a braking state is not achieved or a sufficient braking force cannot be obtained due to a disconnection in a circuit that energizes the coil or a contact failure of a switch. Further, even when the coil and the rotor rub against each other due to abnormal eccentricity of the rotor, the failure or abnormality of the apparatus cannot be detected. In the case of such a failure, it is necessary to repair or replace the eddy current speed reducer immediately.
[0004]
An object of the present invention is to make it possible to easily detect a failure or an abnormal operation in an eddy current type reduction gear using an electromagnet.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, the present invention measures the temperature of an electromagnetic coil or its vicinity, or measures the value of a current flowing through the electromagnetic coil. Then, the measured value is compared with a preset value, and a failure of the eddy current speed reducer is determined based on the comparison result.
[0006]
That is, the eddy current type speed reducer according to the first aspect of the present invention includes at least a braking unit that applies and releases a braking force to a rotating shaft using an electromagnetic field generated by energizing an electromagnetic coil; A first temperature sensor that detects a temperature of the coil; and a determination unit that determines whether there is a failure in the device based on an output of the first temperature sensor.
[0007]
Further, the eddy current type speed reducer according to the second aspect of the present invention includes at least a braking unit that applies and releases a braking force to a rotating shaft by using an electromagnetic field generated by energizing an electromagnetic coil; A current control unit for controlling supply of current to the coil; a current measuring device for measuring a current value supplied from the current control unit to the electromagnetic coil; and presence or absence of a device failure based on an output of the current measuring device. And a judging unit for judging.
[0008]
Note that the first and second aspects can be combined. That is, at the same time as detecting the energization of the electromagnetic coil, the temperature of the electromagnetic coil can be measured as in the first embodiment, and a failure can be determined based on both measurement results.
[0009]
Generally, in an eddy current type speed reducer using an electromagnet, when a current flows to an electromagnetic coil during braking, the electromagnetic coil itself generates heat and becomes higher than the ambient temperature. Conversely, during non-braking, the temperature of the electromagnetic coil drops until there is no difference from the ambient temperature. Here, when the rotor and the electromagnetic coil or the rotor and the iron core rub against each other due to abnormal eccentricity of the rotor, frictional heat is generated and the temperature of the electromagnetic coil increases even during the braking release command. Therefore, if the eddy current type speed reduction device is normal, the device is brought into the non-braking state by the braking release command, and the temperature of the electromagnetic coil does not rise. If the temperature of the electromagnetic coil rises during the braking release command, the eddy current type speed reducer will fail due to the current being supplied to the coil due to poor control, causing a braking condition, or the rotor and the electromagnetic coil rubbing. Can be determined to be.
[0010]
On the other hand, if the eddy current type speed reduction device is normal, the device is brought into a braking state by the braking command, and the temperature of the electromagnetic coil becomes higher than the ambient temperature. If the temperature of the electromagnetic coil does not become higher than the ambient temperature during the braking command, it can be determined that the operation is defective in a non-braking state in which the braking state is not entered.
[0011]
Further, in the eddy current type speed reducer using the electromagnet, the electromagnetic coil is energized during braking and is not energized during non-braking, so that the failure of the speed reducer can be determined by measuring the current flowing through the electromagnetic coil. Note that the first and second aspects may be replaced with a retarder of a type in which a so-called hybrid magnet combining a permanent magnet and an electromagnet is used as a magnetic force source.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
First, a retarder to which the technical idea of the present invention is applied will be briefly described. 1 and 2 are a plan view and a side view showing a schematic configuration of an electromagnet type retarder to which the present invention is applied. In the figure, reference numeral 1 denotes a rotor, and reference numeral 2 denotes a fixing frame for fixing the electromagnet (braking unit) 10. The rotor 1 is connected to a propeller shaft 3 of the vehicle, and rotates in conjunction with the shaft 3. Note that a radiation fin (not shown) is formed on the outer periphery of the rotor 1. A plurality of electromagnets 10 arranged to face the inner peripheral surface of the rotor 1 and a fixed frame 2 for fixing the electromagnets 10 constitute a stator. The electromagnet (braking unit) 10 includes a plurality of iron cores 10a connected to the fixed frame 2 and an electromagnetic coil 10b wound around the outer circumference of each iron core 10a. The electromagnetic coil 10b is connected to a current source (control device) (not shown) and is energized during braking.
[0013]
FIG. 3 is a longitudinal sectional view showing a structure of a main part of a hybrid eddy current type reduction gear (retarder) to which the present invention is applied. FIG. 4 is a cross-sectional view showing a structure of a main part of the retarder shown in FIG. 3, and is a view of FIG. 3 viewed from above. The retarder 110 includes: a rotor 111 fixed to a rotating shaft 116 of the engine via a fixing member 18; braking units (112a, 112b, 114a, 114b) arranged near the rotor 111; And a surrounding case 120. It is needless to say that the present invention can be applied to other types of hybrid type retarders other than the examples shown in FIGS.
[0014]
The rotating shaft 116 is connected to, for example, a propeller shaft of a large vehicle (truck). The rotor 111 is formed in a disk shape, and is arranged so that the rotation shaft 116 passes through the center. The braking unit housed inside the case 120 includes a plurality of electromagnetic coils 112a arranged on the right side of the rotor 116; an iron core 122a penetrating the inside of the electromagnetic coil 112a; and a part embedded in the iron core 122a. A plurality of permanent magnets 114a facing the right side of the rotor 111; a plurality of electromagnetic coils 112b arranged on the left side of the rotor 111; an iron core 122b penetrating the inside of the electromagnetic coil 112b; and a part of the iron core 122b And a plurality of permanent magnets 114 b facing the left side surface of the rotor 111.
[0015]
The adjacent permanent magnets 112a are arranged such that N poles or S poles face each other. Further, the permanent magnets 112a and 112b arranged on both the left and right sides of the rotor 111 are arranged such that the N pole and the S pole face each other. Although not shown, the permanent magnets may be arranged so that the same poles of the permanent magnets face each other as another example.
[0016]
In the retarder having the above-described structure, in a non-braking state (when braking is OFF), the electromagnetic coils 112a and 112b are in a non-energized state in principle. The magnetic field emitted from the N poles of the permanent magnets 114a, 114b passes through the cores 122a, 122b to the inside of the electromagnetic coils 112a, 112b to form a short-circuit magnetic circuit. The magnetic field from the permanent magnets 114a and 114b hardly goes out of the iron cores 122a and 122b.
[0017]
It is preferable that the electromagnetic coils 112a and 112b be in a non-energized state during non-braking. It is also possible to energize the electromagnetic coils 112a, 112b so that the magnetic fields of the electromagnetic coils 112a, 112b and the permanent magnets 114a, 114b have the same direction. In this case, the magnetic field generated from the electromagnetic coil may not pass through the permanent magnet and may flow into the rotor 111.
[0018]
Next, in the braking state (when braking is ON), the electromagnetic coils 112a and 112b are energized in a direction in which the magnetic fields of the electromagnetic coils 112a and 112b and the magnetic fields of the permanent magnets 114a and 114b are opposite. The magnetic field emitted from the N poles of the permanent magnets 114a and 114b repels the magnetic field generated by the electromagnetic coils 112a and 112b, enters the rotor 111, and returns to the S pole of the permanent magnets 114a and 114b. That is, a magnetic circuit is formed between the permanent magnets 114a and 114b and the rotor 111. Then, a braking force is applied to the rotor 111 by an eddy current based on the magnetic fields from the electromagnetic coils 112a and 112b and the magnetic fields from the permanent magnets 114a and 114b.
[0019]
Hereinafter, as a first aspect of the present invention, a retarder having a failure detection function based on the temperature of an electromagnetic coil or its surroundings will be described. At this time, a failure detection function during a braking release command (during vehicle running) (first to fourth embodiments) and a failure detection function during a braking command (during vehicle braking) (fifth to eighth embodiments) are provided. I will explain separately.
[0020]
First Embodiment FIG. 5 is a block diagram showing a configuration of a failure detection unit of an eddy current type reduction gear according to a first embodiment of the present invention. FIG. 6 is a flowchart illustrating a failure detection procedure of the eddy current type reduction gear according to the first embodiment.
[0021]
The failure detection unit according to the present embodiment includes a first temperature sensor 12 that detects the temperature of the coils 10b, 112a, 112b or the iron cores 10a, 122a, 122b that constitute the electromagnet; a controller 14; and a temperature ΔT given from the controller. And a reference temperature ΔTc; and a warning device 16 for giving a predetermined warning such as a flashing of a fluorescent lamp. The controller 14 supplies a braking command (energization) or a braking command release instruction (non-energization) to the braking unit 10. The braking unit 10 starts or stops the braking operation based on a command signal from the controller 14.
[0022]
The first temperature sensor 12 always or directly measures the temperature T of the coils 10b, 112a, 112b. The controller 14 stores the temperature measurement value T0 at the time of switching from the braking command to the braking release command, and stores the difference between the coil temperature measurement value T during the braking release command and the temperature measurement value T0 at the time of switching as the temperature increase value ΔT ( ΔT = T−T0). The comparator 18 compares the temperature rise value ΔT given from the controller 14 with a preset upper limit value ΔTc, and transmits the comparison result to the controller 14. When ΔT ≧ ΔTc, the controller 14 determines that it is a failure of the eddy current type speed reducer, and transmits a failure occurrence signal to the warning device 16. The warning device 16 outputs a warning of abnormality to a driver of the vehicle or a control device of the vehicle. Thus, it is possible to detect a failure of the speed reduction device during a braking release command of the speed reduction device (while the vehicle is running).
[0023]
The coil temperature is directly measured by a temperature measuring means such as a thermocouple, a resistance thermometer, or a thermistor, or an iron core having a correlation between the coil and the temperature is measured. Then, the measured value is used as data for failure detection.
[0024]
The value of ΔTc is set to an optimum value in consideration of the method of measuring the coil temperature and its position, the current value supplied to the coil, and the temperature rise characteristics of the coil itself.
[0025]
When the coil temperature is measured by embedding a thermocouple directly in the coil winding part, if the eddy current speed reducer is not faulty, the device will be in the braking state by the braking command, the coil temperature will rise, and the braking release command The coil temperature drops. On the other hand, even if a brake is released and a current is actually applied to the coil due to a failure and the brake is in a braking state, the coil temperature increases.
[0026]
When the temperature of the coil is directly measured, the coil temperature decreases immediately after the brake release command. However, when the coil temperature is indirectly measured by a thermometer attached to the iron cores 10a, 122a, 122b, etc., the normal condition is obtained by the brake release command. Even when the braking is released, the temperature measurement value of the thermometer rises temporarily. Therefore, it is necessary to set the upper limit value ΔTc in consideration of the amount of temporary increase. Since the temporary temperature rise value varies depending on the measurement position, the temperature rise characteristics of the coil itself, and the like, the test conditions are changed, and the value of ΔTc is further increased in consideration of the rise value when the temperature rises most. It is necessary to
[0027]
Second Embodiment FIG. 7 is a block diagram showing a configuration of a failure detection unit of an eddy current type reduction gear according to a second embodiment of the present invention. FIG. 8 is a flowchart illustrating a failure detection procedure of the eddy current type reduction gear according to the second embodiment. In the description of the present embodiment, components that are the same as or correspond to those of the above-described embodiment are denoted by the same reference numerals, and redundant description will be omitted.
[0028]
This embodiment is obtained by adding control based on the vehicle speed to the apparatus of the first embodiment. As a specific configuration, a vehicle speed sensor 22 and a comparator 24 are added. A vehicle speed V of a vehicle equipped with the eddy current type reduction gear according to the present embodiment is detected by a vehicle speed sensor 22. When the detected vehicle speed V is equal to or higher than the preset value Vc in the comparator 24, it functions similarly to the first embodiment. If the vehicle speed is lower than the value Vc, the failure is not considered even if the temperature rise value ΔT is equal to or higher than ΔTc. That is, the controller 14 does not output an alarm signal to the alarm device.
[0029]
If the rotation of the rotor is suddenly stopped while the electromagnetic coil is at a high temperature, the temperature of the electromagnetic coil itself gradually decreases, but the thermometer mounted near the coil (iron core, etc.) The temperature measurement value increases even during braking. Therefore, when the vehicle speed is low (especially when the vehicle is stopped), the temperature in the vicinity of the coil may significantly increase during the braking release command even though the vehicle is not out of order. Therefore, if the vehicle speed is lower than a certain value Vc, a failure alarm is not issued even if the temperature rise value ΔT is equal to or higher than ΔTc.
[0030]
Third Embodiment FIG. 9 is a block diagram showing a configuration of a failure detection unit of an eddy current type reduction gear according to a third embodiment of the present invention. FIG. 10 is a flowchart showing a failure detection procedure of the eddy current type reduction gear transmission according to the third embodiment. In the description of the present embodiment, the same reference numerals are given to the same or corresponding components as those of the above-described embodiments, and duplicate description will be omitted.
[0031]
The apparatus according to the present embodiment is different from the first embodiment in that control based on the vehicle speed is added so that the upper limit value ΔTc varies depending on the vehicle speed. As a specific configuration, a vehicle speed sensor 22 is added. The relationship between the vehicle speed V and the upper limit value ΔTc is stored in the controller 29 in advance, and the upper limit value ΔTc according to the vehicle speed V at that time is selected. Then, the comparator 18 compares the selected ΔTc and ΔT to determine a failure. This makes it possible to detect a failure more accurately than in the first embodiment or the second embodiment.
[0032]
Fourth Embodiment FIG. 11 is a block diagram showing a configuration of a failure detection unit of an eddy current type reduction gear according to a fourth embodiment of the present invention. FIG. 12 is a flowchart showing a failure detection procedure of the eddy current type reduction gear according to the fourth embodiment. In the description of the present embodiment, the same reference numerals are given to the same or corresponding components as those of the above-described embodiments, and duplicate description will be omitted.
[0033]
The fourth embodiment is configured by combining the second embodiment and the third embodiment. That is, controller 34 adopts a different value as upper limit value ΔTc according to vehicle speed V. Further, if the vehicle speed V is lower than a certain value Vc, no failure alarm is issued.
[0034]
Fifth Embodiment FIG. 13 is a block diagram showing a configuration of a failure detection unit of an eddy current type reduction gear according to a fifth embodiment of the present invention. FIG. 14 is a flowchart showing a procedure for detecting a failure of the eddy current type reduction gear according to the fifth embodiment. In the description of the present embodiment, the same reference numerals are given to the same or corresponding components as those of the above-described embodiments, and duplicate description will be omitted.
[0035]
In the present embodiment, the coil temperature is always directly or indirectly measured by the first temperature sensor 12a, and at the same time, the ambient temperature of a portion not affected by the heat generated by the rotor or the electromagnetic coil is measured by the second temperature sensor 12b. Measure. The output of the first temperature sensor 12a is input to the comparator 48 via the controller 44 or directly. The output of the second temperature sensor 12b is input to the controller 44. The controller 44 calculates a reference value Tc (= Ta + α) based on the ambient temperature Ta detected by the second temperature sensor 12b.
[0036]
Generally, depending on the measurement position of the ambient temperature and the method and position of measuring the temperature of the electromagnetic coil, the ambient temperature and the electromagnetic coil temperature do not always have the same value even in the non-braking state. The optimum value is selected in consideration of these.
[0037]
The comparator 48 compares the coil temperature T with the reference value Tc, and returns the result to the controller 44. When T ≦ Tc, the controller 44 determines that it is a failure of the eddy current type speed reducer, and transmits a warning signal to the warning device 16. The warning device 16 outputs a warning of an abnormality to a driver's seat or a control device of a vehicle. This makes it possible to detect a failure when an operation failure occurs in a non-braking state despite a braking command.
[0038]
Immediately after switching from the non-braking state (during running) to the braking state, the temperature measurement value T does not exceed Ta + α, so that the failure determination is performed after a lapse of the set time ts after the switching of the braking. As a specific configuration, a braking command signal output from the controller 44 is transmitted to the timer 46 in addition to the braking unit 10. The timer 46 measures the time from when the braking command signal is input, and outputs a predetermined signal to the controller 44 after a predetermined time ts has elapsed. If the set time ts has not been reached after the output of the braking command signal, no failure is determined even if T ≦ Tc.
[0039]
Sixth Embodiment FIG. 15 is a block diagram showing a configuration of a failure detection unit of an eddy current type reduction gear according to a sixth embodiment of the present invention. FIG. 16 is a flowchart illustrating a failure detection procedure of the eddy current type reduction gear according to the sixth embodiment. In the description of the present embodiment, the same reference numerals are given to the same or corresponding components as those of the above-described embodiments, and duplicate description will be omitted.
[0040]
In the present embodiment, control based on the vehicle speed V is performed in the failure detection during braking, as in the second embodiment. As a specific configuration, a vehicle speed sensor 22 and a comparator 24 are added. A vehicle speed V of a vehicle equipped with the eddy current type reduction gear according to the present embodiment is detected by a vehicle speed sensor 22. When the detected vehicle speed V is equal to or higher than the preset value Vc in the comparator 24, the comparator 24 functions in the same manner as in the fifth embodiment. If the vehicle speed is lower than the value Vc, the failure is not considered even if the temperature rise value ΔT is equal to or higher than ΔTc. That is, the controller 54 does not output an alarm signal to the alarm device.
[0041]
In general, when the vehicle speed V is low, the temperature of the coil itself hardly rises because the current value flowing through the electromagnetic coil is small even if the device is normally braked by the braking command. For this reason, the value of the thermometer also takes the same value as the ambient temperature. Therefore, when the vehicle speed is low, the temperature measurement value is not much different from the ambient temperature even during the braking command. Therefore, if the vehicle speed is lower than a certain value Vc, a failure alarm is not issued even if the temperature measurement value satisfies T ≦ Tc.
[0042]
Seventh Embodiment FIG. 17 is a block diagram showing a configuration of a failure detection unit of an eddy current type reduction gear according to a seventh embodiment of the present invention. FIG. 18 is a flowchart illustrating a failure detection procedure of the eddy current type reduction gear according to the seventh embodiment. In the description of the present embodiment, the same reference numerals are given to the same or corresponding components as those of the above-described embodiments, and duplicate description will be omitted.
[0043]
In the present embodiment, control is performed based on the vehicle speed V in detecting a failure during braking, as in the third embodiment. That is, the correction amount α takes a different value according to the vehicle speed V. As a specific configuration, a vehicle speed sensor 22 is added. The relationship between the vehicle speed V and the correction amount α is stored in the controller 64 in advance, and the correction amount α according to the vehicle speed V at that time is selected. This makes it possible to detect a failure more accurately than in the fifth and sixth embodiments.
[0044]
Eighth Embodiment FIG. 19 is a block diagram showing a configuration of a failure detection unit of an eddy current type reduction gear according to an eighth embodiment of the present invention. FIG. 20 is a flowchart illustrating a failure detection procedure of the eddy current type reduction gear according to the eighth embodiment. In the description of the present embodiment, the same reference numerals are given to the same or corresponding components as those of the above-described embodiments, and duplicate description will be omitted.
[0045]
The eighth embodiment is configured by combining the sixth embodiment and the seventh embodiment. That is, the controller 74 adopts a different value as the correction amount α according to the vehicle speed V. Further, if the vehicle speed V is lower than a certain value Vc, no failure alarm is issued.
[0046]
Ninth Embodiment Next, a description will be given of a retarder having a failure detection function based on a current value flowing through an electromagnetic coil as a ninth embodiment.
[0047]
FIG. 21 is a block diagram showing the configuration of the failure detection unit of the eddy current type reduction gear according to the ninth embodiment of the present invention. In the description of the present embodiment, the same reference numerals are given to the same or corresponding components as those of the above-described embodiments, and duplicate description will be omitted. The device according to the present embodiment includes a controller 114 that switches between braking and non-braking by supplying a current to the electromagnetic coil 10b, a current detection note 112 that detects a current value flowing through the electromagnetic coil 10b, and a predetermined A warning device 16 for giving a warning.
[0048]
In the present embodiment, when braking the vehicle, a necessary current is supplied (energized) from the controller 114 to the electromagnetic coil 10b. On the other hand, when the vehicle is not braked, the power supply to the electromagnetic coil 10b is cut off. The current detector 112 constantly monitors the value of the current flowing through the electromagnetic coil 10b. Then, if no current flows through the electromagnetic coil 10b even though a braking command is issued from the controller 114, it is determined that the speed reduction device has failed. In addition, even when a current is flowing through the electromagnetic coil 10b despite a braking release command being issued from the controller 114, it is also determined that the speed reducer has failed.
[0049]
The controller 114 includes an energizing circuit for energizing the electromagnetic coil 10b, and the current detector 112 is connected in series between the energizing circuit and the electromagnetic coil 10b. Further, the controller 114 can set a threshold value of energization / non-energization in consideration of a certain amount of current noise or the like. That is, when an extremely small current is detected by the current detector 112, it is determined that no current is supplied. As a result, it is possible to more accurately determine the failure of the reduction gear transmission.
[0050]
This embodiment can be combined with the above-described embodiments. In other words, the temperature of the electromagnetic coil is measured at the same time as detecting the energization of the electromagnetic coil, and a failure can be determined based on the results of both measurements.
[0051]
The embodiments (embodiments, embodiments) of the present invention have been described above. However, the present invention is not limited to these embodiments, and changes may be made within the scope of the technical idea described in the appended claims. It is possible.
[Brief description of the drawings]
FIG. 1 is a plan view showing a schematic configuration of an electromagnet type retarder to which the technical idea of the present invention is applied.
FIG. 2 is a side view of FIG. 1;
FIG. 3 is a longitudinal sectional view showing a structure of a main part of a hybrid type retarder to which the technical idea of the present invention is applied. It is a top view which shows a schematic structure.
FIG. 4 is a cross-sectional view showing a structure of a main part of the retarder shown in FIG. 3;
FIG. 5 is a block diagram illustrating a configuration of a failure detection unit of the eddy current type reduction gear according to the first embodiment of the present invention.
FIG. 6 is a flowchart illustrating a fault detection procedure of the eddy current type reduction gear according to the first embodiment.
FIG. 7 is a block diagram showing a configuration of a failure detection unit of the eddy current type reduction gear according to the second embodiment of the present invention.
FIG. 8 is a flowchart illustrating a failure detection procedure of the eddy current type reduction gear according to the second embodiment.
FIG. 9 is a block diagram showing a configuration of a failure detection unit of the eddy current type reduction gear according to the third embodiment of the present invention.
FIG. 10 is a flowchart illustrating a failure detection procedure of the eddy current type reduction gear according to the third embodiment.
FIG. 11 is a block diagram showing a configuration of a failure detection unit of an eddy current type reduction gear according to a fourth embodiment of the present invention.
FIG. 12 is a flowchart illustrating a fault detection procedure of the eddy current type reduction gear according to the fourth embodiment.
FIG. 13 is a block diagram showing a configuration of a failure detection unit of an eddy current type reduction gear according to a fifth embodiment of the present invention.
FIG. 14 is a flowchart illustrating a failure detection procedure of the eddy current type reduction gear according to the fifth embodiment.
FIG. 15 is a block diagram illustrating a configuration of a failure detection unit of an eddy current type reduction gear according to a sixth embodiment of the present invention.
FIG. 16 is a flowchart illustrating a failure detection procedure of the eddy current type reduction gear according to the sixth embodiment.
FIG. 17 is a block diagram showing a configuration of a failure detection unit of an eddy current type reduction gear according to a seventh embodiment of the present invention.
FIG. 18 is a flowchart illustrating a failure detection procedure of the eddy current type reduction gear according to the seventh embodiment.
FIG. 19 is a block diagram showing a configuration of a failure detection unit of an eddy current type reduction gear according to an eighth embodiment of the present invention.
FIG. 20 is a flowchart illustrating a failure detection procedure of the eddy current type reduction gear according to the eighth embodiment.
FIG. 21 is a block diagram showing a configuration of a failure detection unit of an eddy current type reduction gear according to a ninth embodiment of the present invention.
[Explanation of symbols]
1 rotor 3 propeller shaft 10 braking unit (electromagnet)
10a, 122a, 122b Iron core 10b, 112a, 112b Electromagnetic coil 12 First temperature sensor 14, 114 Controller 16 Warning device 18 Comparator 112 Current detector

Claims (15)

In eddy current type reduction gears using electromagnets,
A braking unit that applies and releases a braking force to the rotating shaft by an electromagnetic field generated by the electromagnetic coil;
A first temperature sensor for detecting the temperature of the electromagnetic coil or the vicinity thereof;
An eddy current type speed reducer, comprising: a determination unit configured to determine the presence or absence of a device failure based on an output of the first temperature sensor. In an eddy current type speed reducer using an electromagnet and a permanent magnet,
A braking unit for applying and releasing a braking force to the rotating shaft by a magnetic field generated by the electromagnetic coil and the permanent magnet;
A first temperature sensor for detecting the temperature of the electromagnetic coil or the vicinity thereof;
An eddy current type speed reducer, comprising: a determination unit configured to determine the presence or absence of a device failure based on an output of the first temperature sensor. The eddy current type reduction gear according to claim 1 or 2, further comprising a warning unit that issues a predetermined warning when a failure of the device is found as a result of the determination by the determination unit. The apparatus according to claim 1, wherein the determination unit determines whether there is a failure in the device using a predetermined reference value and a temperature detected by the first temperature sensor. 5. An eddy current type reduction gear as described in the above. 5. The eddy current type reduction gear according to claim 1, wherein the reference value is determined based on a condition detected by the first temperature sensor and a braking condition of the braking unit. 6. The determination unit determines a difference ΔT (T−T0) between a temperature T0 at the time of a brake release command and a detection value T of the first temperature sensor during a brake release command (during a non-braking operation) in advance. 6. The eddy current type reduction gear according to claim 1, wherein a failure is determined when the temperature difference becomes equal to or larger than ΔTc. A vehicle speed sensor for detecting a speed V of a vehicle on which the eddy current type reduction gear is mounted;
The first temperature sensor is configured to detect a temperature near the electromagnetic coil,
7. The eddy current type reduction gear transmission according to claim 6, wherein the determination unit determines that a failure has occurred only when the vehicle speed V detected by the vehicle speed sensor is equal to or higher than a predetermined vehicle speed Vc. The eddy current type reduction gear according to claim 7, wherein the specified temperature difference ΔTc is set according to a vehicle speed V detected by the vehicle speed sensor. A second temperature sensor that detects a temperature Ta of a portion that is not substantially affected by heat generated by the braking unit;
The determination unit may determine whether a difference (T−Ta) between the detection value T of the first temperature sensor and the detection value Ta of the second temperature sensor during braking is equal to or less than a predetermined reference value α. 6. The eddy current type speed reducer according to claim 1, wherein a failure is determined. It further comprises a timer that detects the time since the braking command was input,
The eddy current type reduction gear device according to claim 9, wherein the determination unit performs a failure determination after a predetermined time has elapsed from the braking command based on an output of the timer. A vehicle speed sensor for detecting a speed V of a vehicle on which the eddy current type reduction gear is mounted;
The first temperature sensor is configured to detect a temperature near the electromagnetic coil,
The eddy current type deceleration according to claim 9 or 10, wherein the determination unit determines that a failure has occurred only when the vehicle speed V detected by the vehicle speed sensor is equal to or higher than a predetermined vehicle speed Vc. apparatus. The eddy current type reduction gear according to claim 11, wherein the reference value α is set according to a vehicle speed V detected by the vehicle speed sensor. In eddy current type reduction gears using electromagnets,
A braking unit that applies and releases a braking force to the rotating shaft by an electromagnetic field generated by the electromagnetic coil;
A current control unit that controls supply of current to the electromagnetic coil;
A current measuring device for measuring a current value supplied to the electromagnetic coil from the current control unit;
An eddy current type speed reducer, comprising: a determination unit for determining the presence or absence of a failure of the device based on an output of the current measuring device. In an eddy current type speed reducer using an electromagnet and a permanent magnet,
A braking unit for applying and releasing a braking force to the rotating shaft by a magnetic field generated by the electromagnetic coil and the permanent magnet;
A current control unit that controls supply of current to the electromagnetic coil;
A current measuring device for measuring a current value supplied to the electromagnetic coil from the current control unit;
An eddy current type speed reducer, comprising: a determination unit for determining the presence or absence of a failure of the device based on an output of the current measuring device. 15. The eddy current type reduction gear according to claim 13, further comprising a warning unit that issues a predetermined warning when a failure of the device is found as a result of the determination by the determination unit.

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