JP6344053B2 - Brush wear notification device - Google Patents

Description

  The present invention relates to a brush wear notification device, and more particularly to a device for reporting brush wear in a motor that supplies electric power to a rotor via a brush.

  As the above notification device, Patent Document 1 discloses a technique in which two electric wires covered with a detection hole of a brush are inserted and a lamp and a battery are provided in series with each electric wire. In this technique, when the brush is worn to a position where the electric wire is exposed, the notification is performed in such a manner that the core wire of each electric wire comes into contact with the commutator and becomes conductive, and the lamp is turned on.

  Japanese Patent Application Laid-Open No. 2004-228561 discloses a technique that includes a switch that is operated by an articulated metal fitting whose posture changes according to the wear of the brush, and that has an alarm unit that issues an alarm based on the output of the switch. In this technique, when the brush is worn, the posture of the connecting metal changes, and notification is performed in a form in which the lamp is turned on by the output signal of the switch.

  Moreover, in patent document 3, when the terminal metal fitting is provided in the inside of the brush holder holding a brush, and the pressing spring which applies a pressing force to the brush inside the brush holder is provided, and the pressing spring contacts the contact of the terminal metal fitting, A technique with a working alarm is shown. In this technique, the alarm is notified by the pressing spring coming into contact with the contact of the terminal fitting due to the wear of the brush.

JP 2002-233114 A JP 2008-79459 A Japanese Patent Laid-Open No. 9-182384

  In the configuration of Patent Document 1, not only a brush processed to insert an electric wire is required, but, for example, it takes time to connect the electric wire to a notification circuit every time the brush is replaced. .

  In addition, the configuration of Patent Document 2 not only requires a structure that changes the posture of the connecting bracket in accordance with the wear of the brush, but also requires a switch for detecting this change in posture, which makes the structure complicated. In addition, the cost of parts was also increased.

  Further, in the configuration of Patent Document 3, there is no trouble in replacing the brush as in Patent Document 1, and the number of parts can be reduced as compared with Patent Document 2. However, since it is necessary to expose the contact inside the brush holder, it is necessary to reduce the size of the contact, which takes time for assembly. In particular, in the configuration in which the contact contacts the outer peripheral surface of the spring, the contact may be unstable, and there is room for improvement.

  An object of the present invention is to configure a wear notification device that detects and notifies the wear of a brush that supplies electric power to a rotor of a motor so as to realize reliable detection without causing complication.

A feature of the present invention is that a torsion spring made of a conductor having an arm portion that presses a brush that contacts a conduction portion of a motor rotor;
A rod portion that is disposed in a posture that intersects a displacement direction of the arm portion due to wear of the brush, and that the arm portion contacts when the arm portion changes to a predetermined posture with wear of the brush; and A detection mechanism having a spring portion for urging the rod portion toward the arm portion;
And a notifying unit for notifying that the arm part and the rod part are in contact with each other and reach a conductive state.

According to this configuration, when the arm portion of the torsion spring reaches a predetermined posture as the brush wears, the arm portion and the rod portion come into contact with each other to reach a conductive state, and notification is performed by the notification portion. Also, even when the brush is further worn and the arm part is further displaced, the rod part is allowed to be displaced by the spring part, so that the detection state is maintained while maintaining the state in which the urging force is applied from the arm part to the brush. It becomes possible to do. In this configuration, since the rod portion of the detection mechanism can be disposed in a region where the arm portion is displaced, the arm portion and the rod portion are reliably brought into contact with each other, and the contact state can be easily maintained.
In particular, in this configuration, it is not necessary to use switches as a detection mechanism, so that the configuration is simple, there are few failures, and there is no increase in cost.
Therefore, the wear notification device for detecting and notifying the wear of the brush that supplies electric power to the rotor of the motor is configured to realize low-cost and reliable detection that is unlikely to cause a failure.

  The present invention further includes a restricting body that sets the rod portion to a set position, the detection mechanism is configured using a torsion coil spring, the spring portion is a coiled portion of the torsion coil spring, and the rod portion is the A rod-shaped portion extending from one end of the coil-shaped portion, wherein the spring portion biases the rod portion in a direction against the displacement direction of the arm portion, and the rod portion You may contact the said regulation body by urging | biasing force.

  According to this, it is possible to form the rod portion in a form extending from one end of the coiled portion of the torsion coil spring in which the wire is formed in a coil shape, and the detection mechanism is simplified. Also, since the rod part is brought into contact with the regulating body by the urging force of the spring part, the rod part also comes into contact with the rod part when the arm part of the torsion spring comes into contact with the rod part and the arm part is subsequently displaced. A predetermined urging force can be applied from the beginning to the arm portion from the portion. As a result, the contact state between the arm part and the rod part is stabilized, and for example, even when vibration is applied from the motor, the contact state between the arm part and the rod part is well maintained.

  The present invention may further include a locking end portion extending from the other end of the coil-shaped portion, and the locking end portion may engage with the restriction body or a portion integrally formed with the restriction body.

  According to this, the urging | biasing force of a spring part is made to act on a rod part by engaging the latching end part extended from the other end of a coil-shaped part with the part integrally formed with the control body or the control body. For example, it is not necessary to provide a special pin or the like for engaging the locking end.

  In the present invention, the restricting body has a restricting surface disposed in a posture intersecting with a displacement plane of the arm portion, and the restricting surface is further displaced after the arm portion contacts the rod portion. In this case, the rod portion may be allowed to move in a direction along the restriction surface.

  When the brush is worn, the arm portion is displaced in a swinging manner about the coiled portion of the torsion spring. Due to such a displacement mode, it is possible to apply a component force that is displaced toward the center direction of the torsion spring to the rod portion that contacts the arm portion as the brush wears. For example, when the arm portion comes into contact with the rod portion for the first time, the arm portion and the spring portion are installed so that the urging force is applied in a direction in which the rod portion is inclined with respect to the arm portion. As a result, as the arm portion presses the rod portion, the extending direction of the swinging arm portion further inclines with respect to the urging direction of the rod portion, and the rod portion slides on the surface of the arm portion while the arm portion slides. It will move to the base end side of the part. As a result, the distance (arm length) between the contact point of the arm portion with the rod portion and the swing center of the arm portion becomes short, and the moment acting on the arm portion from the rod portion becomes small. Therefore, even if it is in the state after an arm part contact | abuts to a rod part, an arm part can press a brush reliably.

According to the present invention, when the arm part is further displaced after contacting the rod part, and the rod part swings to the limit position with the displacement, the rod part is detached from the arm part. Configured as
The control unit further controls the notification unit, and the control unit causes the notification unit to perform notification in the first notification mode when the arm unit comes into contact with the rod unit and reaches a conductive state. When it is determined that the arm part and the rod part are separated after the notification in the first notification mode, the notification unit may perform notification in the second notification mode.

  According to this, when the arm portion is displaced with the wear of the brush and reaches the set position, the state in which the arm portion is in contact with the rod portion is maintained, and the control unit configuring the notification unit is in the first notification mode. Since the notification is performed, the wear of the brush can be grasped. Next, when the brush part wears, the rod part swings, the arm part exceeds the limit position, and when the rod part is separated in such a way that the arm part gets over, the control part performs notification in the second notification mode. Therefore, it is possible to grasp from the notification form that the wear of the brush is further progressing.

1 is an overall view showing a configuration of a brush wear notification device. It is a perspective view which shows a brush, a torsion spring, and a detection mechanism. It is a figure which shows arrangement | positioning of a brush and a torsion spring. It is a top view which shows the arm part and rod part in a non-contact state. It is a side view which shows the arm part and rod part in a non-contact state. It is a top view in the state where the arm part contacted the rod part in the setting position. It is a side view in the state where the arm part contacted the rod part in the setting position. It is a top view which shows the rod part and arm part in a limit position. It is a side view which shows the rod part and arm part in a limit position. It is a top view which shows the rod part and arm part which exceeded the limit position. It is a side view which shows the rod part and arm part which exceeded the limit position.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[Basic configuration]
As shown in FIG. 1, a shaft 3 rotating integrally with a rotor 2 (an example of a motor rotor) is rotatably supported with respect to a housing 1 as a stator, and at a position surrounding the rotor 2 on the inner periphery of the housing 1. A direct current type motor is configured by including a pair of brushes 6 that supply a power to the coil of the rotor 2 by contacting a commutator 5 (an example of a conducting portion) that includes a permanent magnet 4 and rotates integrally with the shaft 3. Yes.

  This motor is provided with a wear notification device A that performs notification by light emission of the light emitting diode 21 (an example of a notification unit) when the amount of wear of the brush 6 reaches a predetermined value. The wear notification device A is assumed to be provided in the motor housing 1, but may be configured to be provided in a device operated by the motor. The motor provided with the wear notification device A may be an AC motor.

  The wear notification device A is informed based on a torsion spring 12 that applies a biasing force that brings the brush 6 into contact with the commutator 5, a detection mechanism As that detects wear of the brush 6, and detection by the detection mechanism As. A light emitting diode 21 is provided as a notification unit that operates.

[Brush part]
As shown in FIGS. 1 to 3, a brush case 11 is provided with respect to a support plate 10 inside the motor, and a brush 6 is supported movably with respect to the brush case 11. The support plate 10 is provided with a torsion spring 12 for applying an urging force for bringing the brush 6 into contact with the commutator 5. A pair of slits 11A are formed in the brush case 11 in a posture parallel to each other, the torsion spring 12 is inserted into one of the slits 11A, and the pigtail 6A of the brush 6 is inserted into the other.

  The brush 6 is formed into a prismatic shape by the inclusion of copper powder and graphite, and a pigtail 6A is formed on the brush 6 as a power feeding point. In this motor, power from the power source 7 is supplied to the pair of pigtails 6A. In addition, the material of the brush 6 is not restricted to this, A metal may be used and only graphite may be used.

  The torsion spring 12 uses a wire material made of a material having a good conductor or low electrical resistance, such as a spring material made of copper alloy or a steel material plated with gold, and the coil portion 12C to the arm portion 12A and the locking portion 12B. And is formed in a structure that extends. A coil support 13 that is inserted into the coiled portion 12C of the torsion spring 12 is provided in the support plate 10, an arm portion of the torsion spring 12 is inserted into one slit 11A of the brush case 11, and a locking portion 12B is provided in the support plate 10. The locking piece 10A is locked.

  The detection mechanism As is disposed in the vicinity of the brush case 11. The detection mechanism As uses a torsion coil spring and is supported by a holder 18 made of an insulating resin. A spring portion 15 is formed by a coiled portion of the torsion coil spring, a rod portion 16 is formed by a portion extending linearly from one end of the coiled portion, and a locking end portion 17 by a portion extending from the other end of the coiled portion. Is formed.

  The spring portion 15, the rod portion 16, and the locking end portion 17 are made of a wire made of a good conductor or a material having low electrical resistance, such as a copper alloy spring material or a steel spring material plated with gold. It has been. Since the spring portion 15 maintains a contact state with the arm portion 12A, an urging force is applied in a direction against the displacement direction of the arm portion 12A, and the urging force is smaller than the urging force of the torsion spring 12. Is set. Further, the cable constituting the detection line 22 is electrically connected to the spring portion 15 so as to be electrically connected to the rod portion 16.

  The holder 18 has a U-shaped cross section and has a pair of side walls 18 </ b> A at opposing positions, and the side walls 18 </ b> A are fixed to the support plate 10 in a posture orthogonal to the moving direction of the brush 6. The pair of side walls 18A may be formed so as to intersect with the displacement plane of the arm portion 12A. Specifically, the regulating surface 18S is in the displacement direction of the arm portion 12A due to wear of the brush 6. It is formed in an intersecting posture.

  The spring portion 15 is disposed in a state of being fitted in an intermediate position between the pair of side walls 18 </ b> A of the holder 18, and the locking end portion 17 is engaged with the one side wall 18 </ b> A of the holder 18. Further, a regulating surface 18S is formed on the inner surface side of the other side wall 18A (an example of a regulating body), and the rod portion 16 is brought into contact with the regulating surface 18S by the urging force of the spring portion 15. Furthermore, the extending direction of the rod portion 16 is set to intersect with the displacement direction of the arm portion 12A of the torsion spring 12. In addition, you may comprise so that the latching end part 17 may be engaged with the member integrally formed in the side wall 18A.

  Thus, the rod portion 16 in the restricted state is maintained at the set position S by contacting the restricting surface 18S of the side wall 18A with the urging force. Further, since the rod portion 16 is kept in contact with the side wall 18A by the biasing force of the spring portion 15, the arm portion 12A of the torsion spring 12 abuts on the rod portion 16, and thereafter the posture of the rod portion 16 is changed by the arm portion 12A. In this case, a predetermined urging force can be applied from the beginning of contact to the arm portion 12A from the rod portion 16. As a result, the contact state between the arm portion 12A and the rod portion 16 is stabilized, and, for example, even when vibration is applied from the motor, the contact state between the arm portion 12A and the rod portion 16 is favorably maintained.

  The wear notification device A includes a control circuit 20 (an example of a control unit) having a DSP, a microprocessor, and the like with a built-in nonvolatile memory, and a light emitting diode 21 (notification unit) so as to be controlled by the output of the control circuit 20. Example). In addition, a detection signal of the pair of rod portions 16 is input to the control circuit 20 via a detection line 22 configured by a wire, and a reference voltage signal applied from the power source 7 to the brush 6 is configured by a wire. Input is performed via the reference voltage line 23.

  When it is determined that the arm portion 12A comes into contact with the rod portion 16 and has reached the conduction state, the control circuit 20 continuously supplies power to the light emitting diode 21 to perform lighting (a first notification described later). Along with the notification in the mode), the fact that the conductive state has been reached is stored in the nonvolatile memory. Thereafter, when it is determined that the rod portion 16 is separated from the arm portion 12A, blinking is performed by intermittently supplying power to the light emitting diode 21 based on information stored in the nonvolatile memory (described later). Second notification mode). This control is realized by software set in the control circuit 20, but the control circuit 20 may be realized by hardware by a combination of logic.

[Operating form]
In this motor, as shown in FIGS. 4 and 5, the inner end of the brush 6 is rectified by bringing the tip of the arm portion 12A of the torsion spring 12 into contact with the outer end of the brush 6 and applying a biasing force. It is in contact with the child 5. With this configuration, as the brush 6 is worn, the arm portion 12A is displaced in such a manner that it swings around the coiled portion 12C. As shown in FIGS. 6 and 7, when the posture of the arm portion 12 </ b> A changes due to wear of one brush 6, and the arm portion 12 </ b> A contacts the rod portion 16 at the set position S, the rod portion 16 moves to the arm portion. The control circuit 20 determines the conduction state and turns on the light-emitting diode 21 (continuous light emission: notification mode in the first notification mode).

  For example, when the rod portion 16 corresponding to the plus-side brush 6 comes into contact, the detection line 22 is grounded via a pull-down resistor in order to determine the contact state by increasing the voltage of the detection line 22. In addition, when the rod portion 16 corresponding to the negative brush 6 comes into contact, the detection line 22 is connected to a power source via a pull-up resistor in order to determine the contact state based on the voltage drop of the detection line 22. .

  As described above, since the biasing force of the spring portion 15 that biases the rod portion 16 is set to be smaller than the biasing force of the torsion spring 12, even after the arm portion 12 </ b> A contacts the rod portion 16, the brush 6 is worn. Accordingly, the arm portion 12 </ b> A is displaced, and the urging force of the torsion spring 12 is continuously applied to the brush 6.

  When the arm portion 12A is displaced in this way, the arm portion 12A is displaced in a swinging manner. With this displacement, as shown in FIGS. 8 and 10, the rod portion 16 serves as a restriction wall. It moves in a direction approaching the coiled portion 12C of the torsion spring 12 along the regulating surface 18S on the inner surface of the side wall 18A. However, when the rod portion 16 moves, the rod portion 16 does not necessarily need to contact the regulating surface 18S on the inner surface of the side wall 18A, and may be separated from the regulating surface 18S as shown in FIGS.

  Thus, when the rod part 16 moves in the direction approaching the coiled part 12C of the torsion spring 12, the distance (arm length) between the position in contact with the arm part 12A and the swing center is shortened. The moment acting on the arm portion 12A from the rod portion 16 is reduced to facilitate the swinging of the arm portion 12A. As shown in FIG. 6, when the arm portion 12A first contacts the rod portion 16, the arm portion 12A and the spring portion 15 are installed so that the urging force acts in a direction in which the rod portion 16 is inclined with respect to the arm portion 12A. Has been. Thereby, as the arm portion 12A presses the rod portion 16, the extending direction of the swinging arm portion 12A further increases the degree of inclination with respect to the urging direction of the rod portion 16, and the rod portion 16 is moved to the arm portion 12A. It moves to the base end side of the arm portion 12A while sliding on the surface. As a result, the distance (arm length) between the contact point of the arm portion 12A with the rod portion 16 and the swing center of the arm portion 12A is shortened, and the moment acting on the arm portion 12A from the rod portion 16 is reduced. Therefore, even if it is in the state after arm part 12A contacted rod part 16, arm part 12A can press a brush certainly.

  In the detection mechanism As, after the arm portion 12A comes into contact with the rod portion 16 at the set position S, the arm portion 12A is further displaced, and immediately after reaching the limit position as shown in FIG. As shown in FIG. 2, the rod portion 16 is displaced in a state of getting over the arm portion 12A. That is, the length of the rod portion 16 is set so that the rod portion 16 is separated from the arm portion 12A due to the displacement of the arm portion 12A. When the control circuit 20 determines that the arm portion 12A is separated from the rod portion 16 after contacting the rod portion 16, the control circuit 20 blinks the light emitting diode 21 to indicate that the amount of wear of the brush 6 is extremely large. Control is performed (repetition of lighting and extinguishing, notification mode in the second notification mode).

  As described above, the user recognizes that the wear amount has reached a predetermined amount due to the first lighting of the light emitting diode 21, and after that, the wear amount of the brush 6 needs to be replaced by switching to the state where the light emitting diode 21 blinks. The user is made aware that the value has been reached. As described above, since the control circuit 20 includes the nonvolatile memory, even if the device is turned on again after the supply of power is stopped as if the device having the motor is turned off, the nonvolatile memory Notification in the second control mode can be performed based on the information.

[Another embodiment]
The present invention may be configured as follows in addition to the embodiment described above.

(A) As a notification unit, a liquid crystal display, a speaker for generating a message by an alarm sound or a human language, and the like are provided. For example, when a liquid crystal display is provided, detailed notification is possible by displaying an icon indicating wear on the display or displaying a message indicating wear. In addition, when an alarm sound or a message in human language is output from a speaker, information can be grasped by voice.

(B) Two light emitting diodes are provided, and one light emitting diode is turned on in the first notification mode, and both light emitting diodes are turned on in the second notification mode. Thus, by using a plurality of light emitting diodes, it is possible to appropriately determine the replacement time of the brush.

(C) In a motor having a plurality of brushes, the wear notification device A is configured to detect only the wear of one brush. With this configuration, the configuration for notification can be simplified.

  INDUSTRIAL APPLICABILITY The present invention can be used for a motor configured to supply power to a rotor with a brush.

2 Rotor (motor rotor)
5 Conducting part (commutator)
6 Brush 12 Torsion Spring 12A Arm 15 Spring 16 Rod 17 Locking End 18A Regulator (Side Wall)
18S restriction surface 20 control section (control circuit)
21 Notification unit (light emitting diode)
As detection mechanism S Setting position

Claims (5)

A torsion spring made of a conductor having an arm portion that presses a brush that is in contact with the conductive portion of the motor rotor;
A rod portion that is disposed in a posture that intersects a displacement direction of the arm portion due to wear of the brush, and that the arm portion contacts when the arm portion changes to a predetermined posture with wear of the brush; and A detection mechanism having a spring portion for urging the rod portion toward the arm portion;
A notifying unit for notifying that the arm part and the rod part have contacted each other and have reached a conductive state;
A regulating body for setting the rod portion at a set position,
The detection mechanism is configured using a torsion coil spring, the spring part is a coiled part of the torsion coil spring, and the rod part is a rod-like part extending from one end of the coiled part,
The spring portion biases the rod portion in a direction against the displacement direction of the arm portion;
A brush wear notification device in which the rod portion is in contact with the regulating body by the biasing force of the spring portion . A torsion spring made of a conductor having an arm portion that presses a brush that is in contact with the conductive portion of the motor rotor;
A rod portion that is disposed in a posture that intersects a displacement direction of the arm portion due to wear of the brush, and that the arm portion contacts when the arm portion changes to a predetermined posture with wear of the brush; and A detection mechanism having a spring portion for urging the rod portion toward the arm portion;
An informing part for informing that the arm part and the rod part have come into contact with each other and have reached a conductive state;
When the arm part is further displaced after coming into contact with the rod part, and the rod part swings to the limit position with the displacement, the rod part is configured to be detached from the arm part. ,
A control unit for controlling the notification unit;
The control unit causes the notification unit to perform notification in the first notification mode when the arm unit comes into contact with the rod portion and reaches a conductive state, and the arm unit after the notification in the first notification mode A brush wear notification device that causes the notification unit to perform notification in the second notification mode when it is determined that the rod part is separated from the rod part . Further comprising a regulating body for setting the rod portion to a set position;
The detection mechanism is configured using a torsion coil spring, the spring part is a coiled part of the torsion coil spring, and the rod part is a rod-like part extending from one end of the coiled part,
The spring portion biases the rod portion in a direction against the displacement direction of the arm portion;
The brush wear notification device according to claim 2 , wherein the rod portion is in contact with the restricting body by an urging force of the spring portion. It further comprises a locking end extending from the other end of the coiled portion,
The brush wear notification device according to claim 1 or 3 , wherein the locking end portion engages with the restriction body or a portion integrally formed with the restriction body. The regulating body has a regulating surface arranged in a posture intersecting the displacement plane of the arm portion;
Said regulating surface is, when the arm portion is further displaced from the contact with the rod portion, claim 1 to permit movement of the rod portion in a direction along the regulating surface, any one of 3, 4 The brush wear notification device according to the item .

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