JPH079573Y2 - Induction motor for vehicle - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle induction motor driven by a variable voltage, variable frequency inverter.

[0002]

2. Description of the Related Art In recent years, an induction motor for a vehicle driven by an inverter has been commonly used and is shown in FIG. FIG. 5 is an upper half sectional view of an induction motor for a vehicle. 1 is a stator, 2 is a rotor, 3 is a rotor shaft, 4 is an iron drive side bracket, 5
Is a roller bearing box, 6 is a roller bearing, 7 is an iron anti-drive side bracket, 8 is a ball bearing box, and 9 is a ball bearing. The stator 1, the rotor 2, and the rotor 3 are the usual constituent parts of an electric motor, and a detailed description thereof will be omitted. However, the iron drive side bracket 4,
The roller bearing box 5, the roller bearing 6, the iron anti-drive side bracket 7, the ball bearing box 8 and the ball bearing 9 are components of the bearing support portion according to the present invention.

Conventionally, an induction motor for a vehicle has a structure in which an iron drive side bracket 4 and an iron anti-drive side bracket 7 of steel or cast iron are provided to support the bearing in order to realize high reliability and high durability of the bearing support portion. Met.

[0004]

As described above, the bracket of the conventional vehicle induction motor is made of steel or cast iron. Therefore, the mass of the entire electric motor becomes large, which imposes a heavy load on the track and hinders the speeding up of the vehicle.

[0005]

The present invention was made for the purpose of reducing the weight of an induction motor for a vehicle. The bracket for supporting the bearing is made of aluminum alloy and made of steel which is disposed on the surface in contact with the bearing box. Shrink-fitting into a boss, wherein the steel boss has a bobbin shape, and the outer diameter of one of the flanges is set to a dimension that does not exceed the thermal expansion dimension of the aluminum alloy bracket during shrink-fitting. Is.

[0006]

Since the bracket according to the present invention is made of an aluminum alloy, the weight of the electric motor can be reduced, and the flanges at both ends of the steel boss greatly improve the thrust load resistance. Further, the above-mentioned constitution in which the outer diameter dimension of the collar portion of the steel boss is limited realizes smooth shrink-fitting work of the aluminum alloy bracket.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described with reference to FIG. 5 which is an upper half sectional view of an induction motor for a vehicle described in the above-mentioned prior art.
FIG. 1 is an external view of the drive side bracket of the present invention, and FIG.
2A is a sectional view taken along the line A--A in FIG.
FIG. 2B is an enlarged view of part C of FIG. 3 is an outline view of the non-driving side bracket of the present invention, and FIG.
4A is a cross-sectional view taken along the line YY of FIG.
FIG. 4B is an enlarged view of part D in FIG. 4'is an aluminum alloy drive side bracket, 7'is an aluminum alloy anti-drive side bracket, 10 is a drive side steel boss, and 11 is an anti-drive side steel boss.

The bearing of the electric motor is supported by the aluminum alloy drive side bracket 4'and the aluminum alloy anti-drive side bracket 7'of the present invention, and these brackets are arranged on the surface contacting the bearing box. The drive-side steel boss 10 and the non-drive-side steel boss 11 are shrink-fitted to each other. Incidentally, these steel bosses have a bobbin shape, and the outer diameter of the collar portion on the one side is configured so as not to exceed the thermal expansion dimension at the time of shrink fitting of the aluminum alloy bracket described above.

In the above structure, by shrink-fitting the aluminum alloy bracket into the steel boss, residual stress acts on the fitting portion between the aluminum alloy bracket and the steel boss to raise the temperature of the induction motor. However, there is no gap between the fitting part of the aluminum alloy bracket and the steel boss, and a robust and reliable bracket can be provided in any use condition.

[0010]

[Effect of the Invention] According to the present invention, the component part where the aluminum alloy bracket is shrink-fitted to the steel boss has the aluminum alloy bracket, which makes 5% to 10% of the mass of the electric motor lightweight, It contributes to speeding up. Further, the flanges at both ends of the steel boss greatly improve the thrust load bearing capacity of the fitting portion, and provide a highly reliable bracket. further,
By providing a steel boss at the joint with the bearing box, it is possible to prevent galling and swelling of the joint surface, which is expected to occur during disassembly and assembly for repairing the motor, and to prevent vibration of the joint. The durability against shock and impact can be maintained as same as the conventional one.

[0011]

[Brief description of drawings]

FIG. 1 is an external view of a drive-side bracket showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA in FIG. 1 and a partially enlarged view thereof.

FIG. 3 is an outline view of a non-driving side bracket showing an embodiment of the present invention.

FIG. 4 is a sectional view taken along the line EE in FIG. 3 and a partially enlarged view thereof.

FIG. 5 is a cross-sectional view of an upper half portion of a conventional vehicle induction motor.

[0012]

[Explanation of symbols]

 1 Stator 2 Rotor 3 Rotor shaft 4'Aluminum alloy drive side bracket 5 Roller bearing box 7'Aluminum alloy anti-drive side bracket 8 Ball bearing box 10 Drive side steel boss 11 Anti drive side steel boss

Claims (1)

[Scope of utility model registration request] 1. A vehicle induction motor driven by a variable voltage, variable frequency inverter, comprising a steel boss arranged on a surface in contact with a bearing box and an aluminum alloy bracket shrunk on the steel boss. The steel boss has a bobbin shape, and the outer diameter of one of the flanges is set to a dimension that does not exceed the thermal expansion dimension of the aluminum alloy bracket during shrink fitting.