JP2001327111A - Totally-enclosed motor and electrically-driven vehicle for industry which uses the totally-enclosed motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent external foreign matter from being sucked to the inside of a totally-enclosed motor from a seal part by making the internal pressure of the motor equal to the external pressure. SOLUTION: A totally-enclosed motor 4 for rotating and driving wheels for running is installed in a car body. An air-breathing hole 20 which is continuously connected with the inside and the outside is formed in a main body case 11 of the motor 4. One end portion of an air-breathing tube 21 is connected with an outside aperture of the hole 20, and the other end portion of the tube 21 is raised upward. As a result, the internal pressure of the motor 4 balances always with the external pressure (atmospheric pressure).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fully closed motor and an electrically driven industrial vehicle using the fully closed motor.

[0002]

2. Description of the Related Art Conventionally, as an example of an industrial vehicle, there is an electrically driven wheel loader. The vehicle body of the wheel loader is provided with a plurality of front and rear traveling wheels and a motor for rotating and driving each traveling wheel. In consideration of the working environment of the wheel loader, each of the above-mentioned motors is of a fully-closed type with a closed structure, thereby preventing foreign substances such as gravel, pebbles or rainwater from entering the inside of the motor. ing.

[0003] According to this, when the wheel loader is running by driving the motor, the temperature inside the motor rises due to heat generated by the load, and the internal pressure of the motor rises. When the motor is stopped to stop the traveling of the wheel loader, a phenomenon occurs in which the temperature in the motor decreases and the internal pressure of the motor decreases.

[0004]

However, in the above-mentioned conventional type, the change in the internal pressure of the motor cannot be absorbed, and the internal pressure of the motor becomes lower than the atmospheric pressure. Such foreign substances are sucked into the inside of the motor from the seal portion of the motor, which causes insulation failure of the motor.

SUMMARY OF THE INVENTION An object of the present invention is to make the internal pressure of a motor equal to the external pressure in response to a temperature change, thereby preventing external foreign substances from being sucked into the motor.

[0006]

In order to achieve the above object, a fully-closed motor according to the first aspect of the present invention is provided with a breathing hole communicating with the inside and outside of a main body case.

According to this, even if the internal or external temperature of the fully-closed motor changes, the internal pressure of the fully-closed motor is always equal to the external pressure (atmospheric pressure) through the vent hole formed in the main body case. (Balance). For this reason,
External foreign substances can be prevented from being sucked into the motor from the seal portion of the motor or the like.

In the fully closed motor according to the second aspect of the present invention, a breathing pipe is provided outside the main body case, and one end of the breathing pipe is connected to a breathing hole.

According to this, the internal pressure of the fully closed motor is always equalized (balanced) with the external pressure (atmospheric pressure) through the breather tube and the breather hole. Also, for example, even in the event that the breathing hole is submerged, by preventing the other end of the breathing tube from projecting above the water surface, water is prevented from flowing into the fully closed motor from the breathing hole. I can do it.

An electric drive type industrial vehicle using a fully closed motor according to the third aspect of the present invention is provided with a traveling wheel and a fully closed motor for rotating the traveling wheel on a vehicle body. A breather hole communicating with the inside and the outside is formed in the main body case.

[0011] In the electric drive type industrial vehicle using the fully-closed motor according to the fourth aspect of the present invention, a breathing pipe is provided outside a main body case, and one end of the breathing pipe is connected to a breathing hole. .

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 3, reference numeral 1 denotes an electric drive type wheel loader which is an example of an electric drive type industrial vehicle. A plurality of fully-closed motors 4 for rotationally driving the wheels 3, a generator 5 for supplying electric power to the fully-closed motors 4, an engine 6 for driving the generator 5, and an AC power from the generator 5. An inverter 7 for changing the frequency and supplying the frequency to each motor 4 is provided.

The structure of the fully closed motor 4 will be described below. That is, as shown in FIG. 1, a shaft 13 rotatably held by a bearing 12 is provided inside a main body case 11. A rotor core 14 and a rotor conductor 15 are provided on the outer periphery of the shaft 13. Further, a stator core 16 and a stator winding 17 are provided on an inner peripheral portion of the main body case 11.

The main body case 11 comprises a cylindrical body 11a and end covers 11b and 11c attached to both ends of the body 11a. The joint A between the body 11a and one end cover 11b is O
-Sealed by a seal material (not shown) such as a ring, and similarly, the body 11a and the other end cover 11
Joint B with c is a sealing material such as an O-ring (not shown)
Sealed by.

One end of the shaft 13 penetrates one end cover 11b and protrudes outside. Also,
The bearing 12 is held inside both end covers 11b and 11c. On the other end cover 11c,
A breather hole 20 communicating with the inside and the outside is formed. Also, as shown in FIG. 2, the other end cover 11c
A breather pipe 21 bent in an L-shape is provided on the outside. One end of the breather pipe 21 is connected to an outer opening of the breather hole 20 via a pipe joint 22 (a bite type or the like). The other end of the breather tube 21 is raised upward.

A reducer 19 with a brake is connected to one end of the shaft 13 of each of the fully-closed motors 4. The rotation of the shaft 13 is reduced by the reducer 19 with the brake, and Is transmitted to

The operation of the above configuration will be described below.
According to this, the shaft 13 of each fully closed motor 4 is rotationally driven by the AC power supplied from the generator 5, and each traveling wheel 3 is rotated, so that the wheel loader 1 travels.

Even if the internal temperature of the main body case 11 changes due to the drive or stop of each of the fully-closed motors 4 or the external temperature of the main body case 11 changes due to weather, season, etc.
Through the breather hole 20 and the breather tube 21, the internal pressure of the main body case 11 is always equalized (balanced) with the external pressure (atmospheric pressure). For this reason, it is possible to prevent foreign matter such as external dust, rainwater, and oil from being sucked into the inside of the main body case 11 from the joints A and B (corresponding to the seal portion), and prevent insulation failure of the motor 4. I can do it.

As shown in FIG. 2, even if the breathing hole 20 is submerged, the other end of the breathing tube 21 projects upward to the water surface C because it is raised upward.
Thus, it is possible to prevent water from flowing into the main body case 11 from the breather hole 20.

In the above embodiment, the breathing tube 21 is connected to the breathing hole 20, but the breathing tube 21 may not be connected. In addition, the other end of the breather pipe 21 is raised upward, but is not limited to upward, and may be downward or laterally.

In the above embodiment, the breather pipe 21 is connected to the breather hole 20 by using the pipe joint 22. However, the breather pipe 21 is directly connected to the breather hole 20 by welding or the like without using the pipe joint 22. You may connect.

In the above-described embodiment, the wheel loader 1 has been described as an example of the electric drive type industrial vehicle. However, the present invention is not limited to the wheel loader 1, but may be a forklift or a transport vehicle.

In the above embodiment, the breather hole 20 is formed in the other end cover 11c. However, the breather hole 20 may be formed in the one end cover 11b or in the body 11a.

As another embodiment of the present invention, as shown in FIG. 4, a wire mesh 25 having a small opening is provided at the other end opening of the breather pipe 21 so that foreign matter such as dust can be removed from the other end opening. It may be prevented from entering the inside of the breather tube 21 from the inside.

[0025]

As described above, according to the present invention, even if the internal temperature or the external temperature of the fully-closed motor changes, the internal pressure of the fully-closed motor always becomes external through the breathing hole formed in the main body case. Pressure (atmospheric pressure). For this reason, external foreign substances can be prevented from being sucked into the inside of the motor from a seal portion of the motor or the like, and insulation failure of the motor can be prevented.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a main configuration of a fully-closed motor according to an embodiment of the present invention.

FIG. 2 is a detailed view of a breathing hole and a breathing pipe of the fully-closed motor.

FIG. 3 is a plan view showing a main configuration of a wheel loader that travels with a fully-closed motor.

FIG. 4 is a detailed view of a vent hole and a vent tube of a fully-closed motor according to another embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 wheel loader (electrically driven industrial vehicle) 2 body 3 running wheel 4 fully closed motor 11 body case 20 breather hole 21 breather tube

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Tetsuji Tanaka 1-15-10 Kyomachibori, Nishi-ku, Osaka-shi, Osaka F-term in TCM Corporation (reference) 3D035 DA02 5H605 AA02 AA03 BB05 BB10 BB17 CC01 DD07 DD16

Claims (4)

[Claims] 1. A fully-closed motor in which a main body case is formed with a vent hole communicating between the inside and the outside. 2. The fully closed motor according to claim 1, wherein a breathing pipe is provided outside the main body case, and one end of the breathing pipe is connected to a breathing hole. The vehicle body is provided with a traveling wheel and a fully-closed motor that rotationally drives the traveling wheel, and a breathing hole communicating with the inside and the outside is formed in a body case of the fully-closed motor. An electrically driven industrial vehicle using a fully closed motor. 4. The electric drive type industrial apparatus according to claim 3, wherein a breathing pipe is provided outside the main body case, and one end of the breathing pipe is connected to the breathing hole. For vehicles.