JP2002125349A - Brush holder device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce dimensions of a brush holder device, and to relax restrictions on a maximum current and continuous current application time. SOLUTION: Heat generated by a brush 16 is absorbed by a Peltier device 7 via a metal plate 9, and further, pumped into a housing 17, which is a heatsink for cooling the metal plate 9 and the housing 17.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brush holder device for a motor for an electric power steering device, and more particularly to a cooling mechanism for the motor.

[0002]

2. Description of the Related Art FIG. 8 is a plan view showing a brush holder device of a conventionally used motor for an electric power steering device, FIG. 9 is a sectional view taken along line AA of FIG. 8, and FIG. FIG. 8 and 9, 41 is a brush holder base, 42 is a metal holder, 43 is a metal plate, 44 is a brush, 45 is a spring, 46 is a grommet, and 47 is a lead wire. 10, 48 is a yoke, 49 is a bearing, 50 is an amateur, 51 is a brush holder device, 52 is a housing, 53
Is the boss.

[0003]

The conventional motor for an electric power steering device is constructed as described above. However, the brush holder base is made of resin, the temperature of the brush rises, and the brush holder base is removed. When the resin is melted, the sliding of the brush becomes poor. In the worst case, when the motor is locked, there is a possibility that a serious mode in which steering cannot be performed may occur. In general, a relatively large frequency must be supplied to the motor at this time, even though the frequency is relatively low when the vehicle is put in a garage, and the temperature of the brush rises, so that the maximum current value of the motor and the continuous energizing time are limited. In order to increase the heat capacity of the motor, it is necessary to increase the size of the motor.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an electric power steering apparatus motor capable of reducing the size of the apparatus and relaxing the restrictions on the maximum current value and the continuous energizing time. It is intended to provide.

[0005]

According to a first aspect of the present invention, there is provided a brush holder device comprising: a brush housed in a metal plate; and a housing housing the metal plate and the brush. A Peltier device for cooling the brush is provided.

In a brush holder device according to a second aspect of the present invention, the heat absorbing side of the Peltier element is provided on the metal plate, and the heat generating side is provided on the housing.

A brush holder device according to a third aspect of the present invention is provided with a control device for storing the amount of current to the motor and controlling the current to the Peltier element based on the amount of current.

The brush holder device according to a fourth aspect of the present invention is provided with a control device for detecting the temperature of the motor and controlling the amount of current supplied to the Peltier element based on the detected temperature.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory diagram showing the principle of electronic cooling and heating of a Peltier element as a premise technology of the present invention. In the figure, two types of semiconductors, a P-type element 1 and an N-type element 2, are joined by a metal electrode 3 to form a π-type series circuit. When a current flows in the direction of P → N of the P and N pairs, heat is absorbed at the upper part of the π-type series circuit by the Peltier effect,
Heat is generated in the lower part, and heat is pumped from the upper part to the lower part.

FIG. 2 is a plan view of the brush holder device according to the first embodiment of the present invention as viewed from below, FIG. 3 is a sectional view taken along line BB of FIG. 2, and FIG. 4 is a sectional view showing a motor. In the figure, 4 is a brush holder base, 5 is a grommet,
6 is a lead wire, 7 is a Peltier element as a cooling element,
8 is a metal brush holder, 9 is a metal plate in contact with the resin of the brush holder, 10 is a brush, 11 is a spring, and the heat absorbing side of the Peltier element 7 is attached to the bottom surface of the metal plate 9.

Further, in FIG.
Is a bearing, 14 is an amateur, 15 is a brush holder device, 16 is a brush, 17 is a housing made of aluminum or the like, and 18 is a boss. The Peltier element 7 is attached to the metal plate 9 of the brush holder device 15 and is in contact with the housing 17.

In the motor configured as described above, heat is generated in the brush 16 by energization. However, when the Peltier element 7 is energized, the heat generated in the brush 16 is transferred from the metal plate 9 to the Peltier element 7. Heat is absorbed and pumped to the housing 17 which is a heat sink.
By bringing the heat generation side into contact with the housing 17, the cooling effect can be improved. The heat absorption by the Peltier element 7 cools the metal plate 9 and also cools the brush 16.

At this time, the control device stores the amount of current to the motor, and controls the current to the cooling element based on the amount of current. Alternatively, it is possible to prevent unnecessary cooling by detecting the temperature of the motor or the ambient temperature of the motor and controlling the amount of current supplied to the Peltier element 7 based on the detected temperature.

In the electric power steering apparatus configured as described above, when a certain current is continuously supplied for a predetermined time or more, the Peltier element 7 is supplied with current.
The temperature rise of the brush 16 can be suppressed. Thereby, the deterioration of the brush 16 due to heat can be reduced, and the motor performance can be stabilized. Further, as compared with the conventional electric power steering apparatus, the maximum current value can be increased, and the continuous energizing time can be extended, so that the motor performance suppressed by heat can be sufficiently exhibited.

In the prior art, it was necessary to increase the size and surface area in order to increase the heat capacity and dissipate heat. However, in the present invention, since the size of parts can be reduced, the motor can be reduced in size. Further, even if the cost of the Peltier element is taken into consideration, the cost is reduced as a whole. In addition, since the mounting space for the motor can be reduced and the brush size can be reduced, it is also effective in reducing the brush noise. Further, since the brush can be reduced in size, the commutator can also be reduced in size, leading to a reduction in loss torque and inertia of the motor, which is particularly effective as a motor for an electric power steering device.

As described above, according to this embodiment, by cooling the brush 16, deterioration of the brush 16 due to heat can be reduced, and the performance of the motor can be stabilized. Further, since the temperature rise of the motor is suppressed, the maximum current value can be increased and the continuous energizing time can be extended.

Furthermore, it is possible to use a small motor,
The cost increase of the cooling element can be absorbed, and the mounting space can be reduced by using a small motor. or,
The brush noise can be reduced by reducing the brush size, and the loss torque and inertia of the motor can be reduced by reducing the commutator.

Embodiment 2 FIG. FIG. 5 is a plan view showing a brush holder device to which a Peltier element according to Embodiment 2 of the present invention is attached, FIG. 6 is a plan view showing a housing ASSY, and FIG. 7 is a sectional view showing a motor. In the figure, 1
9 is a brush holder base, 20 is a metal brush holder, 2
1 is a metal plate, 22 is a brush, 23 is a spring,
Reference numeral 24 denotes a Peltier element. The Peltier element 24 is attached to the back of the metal plate 21. Also, 25
Is a brush holder device, 26 is a housing, and the Peltier element 24 is in contact with the housing 26.

In FIG. 7, reference numeral 27 denotes a yoke, 28 denotes a bearing, 29 denotes an armature, 30 denotes a brush holder device, 31 denotes a brush, and 32 denotes a boss.
4 is attached to the back of the metal plate 21 of the brush holder device 30 and is in contact with the housing 26.

[0020]

According to the brush holder device according to the first aspect of the present invention, the brush housed in the metal plate,
It is composed of a metal plate and a housing for accommodating the brush, and is provided with a Peltier element for cooling the brush, so that the limitation of the maximum current value and the continuous energizing time can be relaxed and the size of the device can be reduced. Can be planned.

According to the brush holder device of the present invention, the heat absorbing side of the Peltier element is provided on the metal plate and the heat generating side is provided on the housing, so that the brush can be effectively cooled.

According to the brush holder device of the third aspect of the present invention, the control device for storing the amount of current to the motor and controlling the current to the Peltier element based on the amount of current is provided. Cooling can be prevented.

According to the brush holder device of the fourth aspect of the present invention, the control device is provided for detecting the temperature of the motor and controlling the amount of current supplied to the Peltier element based on the detected temperature.
Unnecessary cooling can be avoided.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the principle of electronic cooling and heating of a Peltier device.

FIG. 2 is a plan view showing a brush holder device according to the first embodiment of the present invention.

FIG. 3 is a sectional view taken along line BB of FIG. 2;

FIG. 4 is a sectional view showing a motor.

FIG. 5 is a plan view showing a brush holder device according to Embodiment 2 of the present invention.

FIG. 6 is a plan view showing a housing ASSY.

FIG. 7 is a sectional view showing a motor.

FIG. 8 is a plan view showing a conventional brush holder device.

FIG. 9 is a sectional view taken along line AA of FIG. 8;

FIG. 10 is a sectional view showing a conventional motor.

[Explanation of symbols]

7,24 Peltier element, 9,21 metal plate, 1
0,31 brush, 17,26 housing.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5H609 PP12 QQ25 RR65 SS23 5H613 AA06 BB04 BB11 BB15 BB27 GA12 GB12 GB13 PP03 QQ07 RR05 SS13 SS14

Claims (4)

[Claims] A brush housed in a metal plate;
A brush holder device comprising a metal plate and a housing for accommodating a brush, wherein a Peltier element for cooling the brush is provided. 2. The brush holder device according to claim 1, wherein the heat absorbing side of the Peltier element is provided on the metal plate, and the heat generating side is provided on the housing. 3. The brush holder device according to claim 1, further comprising a control device for storing the amount of current supplied to the motor and controlling the power supply to the Peltier element based on the amount of current supplied. 4. The brush holder device according to claim 1, further comprising a control device for detecting a temperature of the motor and controlling an amount of current supplied to the Peltier element based on the detected temperature.