JPH0596959A - Electric running vehicle - Google Patents

Abstract

PURPOSE:To sufficiently generate output of an electric motor and improve durability of a power transmission mechanism by cooling the motor and the power transmission mechanism in a simple construction and efficiently. CONSTITUTION:Both the motor 1 of an electric running vehicle and a power transmission mechanism 4 to transmit the power to drive wheels 3 are received in a case 5 of one body. The case 5 is provided with a water jacket 16 for cooling the motor and the power transmission mechanism.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric vehicle in which drive wheels are driven by an electric motor via a power transmission mechanism for transmitting the power of the electric motor.

[0002]

2. Description of the Related Art Electric motors and power transmission mechanisms for electric vehicles are
It is known that heat is generated during operation, and the temperature rise due to this heat deteriorates the performance of the electric motor and the power transmission mechanism. That is, when the temperature of the electric motor rises, the efficiency of the electric motor decreases and its output decreases. Therefore, in order to generate a desired output, a relatively large amount of current has to be passed through the electric motor, which leads to faster battery consumption,
Battery life is reduced. When the temperature of the electric motor further rises, the insulating property of the winding and the magnetic force of the magnetic substance may be lost. Further, in the case where a pulley / belt type continuously variable transmission CVT is adopted as the power transmission mechanism, if the temperature rises, the strength of the belt member decreases and the contact surfaces of the belt and the pulley contact each other. Accelerates wear and reduces durability. When the temperature of the power transmission mechanism further rises, there is a problem that the precision is deteriorated due to the thermal expansion of each component and the power transmission capacity is lowered due to the higher heat of the sliding portion.

Therefore, in order to prevent the temperature rise due to heat generation of the electric motor and the power transmission mechanism, they are generally cooled.

In order to cool the electric motor and the power transmission mechanism,
It is conceivable to provide a ventilation part around the electric motor and the power transmission mechanism to radiate heat, so-called cooling by air cooling.

However, in such an air-cooled type, the degree of heat radiation remarkably differs depending on the structure of the ventilation part and the positions of the electric motor and the power transmission mechanism. Therefore, according to the air-cooling method, the cooling capacity is limited, and therefore efficient cooling may be limited.

It is also conceivable to provide a water jacket around the electric motor and the power transmission mechanism, connect a radiator or the like to this water jacket, and circulate cooling water to radiate heat, so-called water cooling type cooling.

However, the electric motor and the power transmission mechanism are usually housed in separate cases, and a water jacket must be provided for each of these cases. Therefore, the structure is complicated by the plurality of water jackets, and a large space is required for piping for connecting the water jackets to each other.

[0008]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention cools an electric motor and a power transmission mechanism with a simple structure and efficiently to generate a sufficient output of the electric motor and to transmit the power. It is an object of the present invention to provide an electric vehicle that can improve the durability of the mechanism.

[0009]

In order to achieve the above object, the present invention provides an electric traveling vehicle in which drive wheels are driven by the electric motor via a power transmission mechanism for transmitting the power of the electric motor. It is characterized in that a case that integrally houses the power transmission mechanism is provided, and that the case is provided with a water jacket that cools the electric motor and the power transmission mechanism.

[0010]

According to the present invention, the electric motor and the power transmission mechanism are housed together by an integral case having a water jacket. Thus, the water jacket integrally surrounds the electric motor and the power transmission mechanism, so that the electric motor and the power transmission mechanism are collectively and efficiently cooled. Furthermore,
It becomes possible to eliminate the piping and make it compact.

[0011]

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is an explanatory view showing a part of an electric vehicle according to an embodiment of the present invention, in which 1 is an electric motor and 2 is an electric motor 1.
A drive circuit unit 3 for driving a drive wheel 3, a power transmission mechanism 4 for transmitting power of the electric motor 1 to the drive wheel 3, and a case 5 for accommodating the electric motor 1, the drive circuit unit 2 and the power transmission mechanism 4 integrally. is there.

Next, each part will be described.

As shown in FIG. 1, the electric motor 1 includes a case 5
It comprises a coil 6 fixedly provided on the inner wall, and a rotor 8 in which a rotating shaft 7 is supported in a case 5, and its drive is controlled by the drive circuit unit 2. It is well known that the electric motor 1 generates heat when it is driven.

The drive circuit unit 2 controls the current sent from the battery (not shown) to the electric motor 1. When a relatively large current is passed through the electric motor 1, the drive circuit unit 2 also receives a large current. It may flow and generate heat.

As the power transmission mechanism 4, a pulley / belt type continuously variable transmission CVT is adopted, and a rotary shaft 7 of the electric motor 1 is used.
Power is transmitted to the drive gear 13 via the belt 11 and the clutch 12 which are stretched between the drive pulley 9 and the driven pulley 10. The drive gear 13 meshes with the driven gear 15 of the differential gear 14, and the drive wheel 3 is driven via the differential gear 14. Pulley / belt type continuously variable transmission CVT which is the power transmission mechanism 4.
Is known to generate heat due to friction of a belt or the like.

The case 5 has a water jacket 16 between its inner wall and outer wall. Cooling water is filled in the water jacket 16. The water jacket 16 is, as shown, in particular the electric motor 1,
It has a structure in which a relatively large amount of cooling water is circulated in a portion corresponding to the drive circuit unit 2 and the power transmission mechanism 4.
Further, a radiator 17 is provided adjacent to the case 5. The radiator 17 is connected in communication with the inside of the water jacket 16, and the cooling water is circulated through the water jacket 16 and the radiator 17 by a pump 18 provided adjacent to the radiator 17.

With the above structure, even if the electric motor 1, the drive circuit unit 2 and the power transmission mechanism 4 generate heat, they can be efficiently cooled by the water jacket 16 and the radiator 17, and the case 5 is the electric motor. 1 and the power transmission mechanism 4 are integrally housed, and further, the drive circuit unit 2 that may generate heat when a large current flows is also housed integrally, and moreover, is integrally surrounded by the water jacket 16. As compared with the prior art, the number of pipes is smaller and the structure is compact, so that the electric motor 1, the power transmission mechanism 4, and the drive circuit unit 2 can be reliably cooled.

In this embodiment, the radiator 17
Although the radiator 1 and the water jacket 16 are provided adjacent to the case 5, the radiator 1 and the water jacket 16 are connected to each other by a water conduit pipe or the like (not shown) so that the radiator 1 can be placed at a position with a higher cooling effect.
It is possible to install only 7.

Further, as shown in FIG.
Is a continuous installation portion 1 that can be opened and closed near the drive circuit unit 2.
9, and a continuous installation portion 20 that can be opened and closed near the power transmission mechanism 4
Is provided so that the drive circuit unit 2 and the power transmission mechanism 4 can be freely exposed, and maintenance work for them can be facilitated.

FIG. 2 is an explanatory view showing the main part of another embodiment. The same reference numerals as those in FIG. 1 in FIG. 2 are the same as those in the above-described embodiment.

As shown in FIG. 2, a cooling fan 21 rotated by the electric motor 1 is provided coaxially with the rotary shaft 7 of the electric motor 1, and the electric motor 1, the drive circuit unit 2 and the power transmission mechanism 4 are integrally housed. Cooling fins 23 in case 22
Further, a cover 25 may be provided to form the air passage 24 by mounting the cooling fins 23 at intervals. The cover 25 is formed with an intake port 26 for sending air to the cooling fan 21. The water jacket 16 is filled with cooling water and sealed.

With the above configuration, the cooling fan 21 rotates as the electric motor 1 is driven, and air is forced to flow through the air passage 2.
Pass 4. As a result, the cooling water in the water jacket 16 is cooled via the cooling fins 23, and at the same time,
Natural convection occurs in the cooling water and circulates inside the water jacket 16.

As described above, in the present embodiment, the cooling water inside the water jacket 16 can be cooled without providing a radiator or the like, so that the electric motor 1, the power transmission mechanism 4 and the drive circuit can be constructed in a more compact structure. The unit 2 can be cooled reliably.

Further, in both of the above-described embodiments, since the electric motor 1 and the power transmission mechanism 4 are both housed in the integrated cases 4 and 22, the electric motor 1 and the power transmission mechanism 4 are included.
Since noise and the like generated when driving the electric vehicle are prevented, the electric traveling vehicle can be quietly driven.

In both of the above-mentioned embodiments, the pulley / belt type continuously variable transmission CVT is adopted as the power transmission mechanism 4, and the cooling suitable for the CVT is realized. 22 and its water jacket 1
According to the structure of 6, the same effect can be obtained even with a power transmission mechanism of another method.

[0027]

As is apparent from the above, according to the present invention, even if the electric motor or the power transmission mechanism generates heat, it is efficiently cooled by the water jacket, so that the output of the electric motor is sufficiently generated and the power transmission is performed. The durability of the mechanism can be improved. Further, since the case houses the electric motor and the power transmission mechanism integrally, and the water jacket integrally surrounds the electric motor and the power transmission mechanism, almost no piping space is required, and the power transmission with the electric motor is compact with a compact structure. It is possible to reliably cool the mechanism.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a part of an electric vehicle according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a main part of another embodiment of the present invention.

[Explanation of symbols]

1 ... Electric motor, 3 ... Drive wheel, 4 ... Power transmission mechanism, 5 ... Case, 16 ... Water jacket.

Claims (1)

[Claims] 1. An electric traveling vehicle in which drive wheels are driven by the electric motor via a power transmission mechanism for transmitting the power of the electric motor, and a case for accommodating the electric motor and the power transmission mechanism is provided in the case. An electric traveling vehicle comprising a water jacket for cooling the electric motor and the power transmission mechanism.