JPH04145801A - Electric motor vehicle - Google Patents

Abstract

PURPOSE:To conserve electric power and to increase traveling distance by stopping an oil supply pump for cooling a motor when an indicated value of a temperature sensor provided in the motor connected to a battery to drive wheels is lower than a predetermined value. CONSTITUTION:Bearing lubricant of traveling induction motors 1a, 1b is sucked from an oil tank 2 by a pump 4a driven by a motor 3a, its hydraulic pressure is regulated by a relief valve 5, and the lubricant is supplied to turn ON a pressure switch 11. When the motor 3a is started, a motor 3b is also started, the lubricant is applied to a filter 10 by a pump 4b, and then fed back to a tank 2a. Coil cooling oil of motors 1a, 1b is also circulated by pumps 4c, 4c driven by the motors 3a, 3b. When detected temperatures of temperature detectors 12a, 12b provided in a lubricant return passage are lower than a predetermined value, the operations of the motors 3a, 3b for driving the pumps 4a, 4b are stopped. Thus, power consumption of a battery (not shown) is conserved, and traveling distance is increased.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electric vehicle, and more particularly to an electric vehicle suitable for cooling electric motors that drive wheels.

[Conventional technology]

An electric vehicle that uses current supplied from a battery to rotate an electric motor and drive wheels is disclosed, for example, in Japanese Patent Application Laid-open No. Sho [i2-
]38002, is widely known.

In such electric vehicles, the driving electric motor is small and compact in order to reduce vehicle weight and make effective use of vehicle space.
Must have high output. For this reason, oil cooling of the electric motor is essential, and furthermore, the electric motor of the electric vehicle needs to be a high-speed motor, and oil lubrication of the bear link is also essential.

Conventional oil cooling systems used to cool induction motors, known as the driving motors used in electric vehicle drive systems, use a single pump motor to circulate motor cooling oil and bearing lubricating oil. Ta.

[Problems to be Solved by the Invention] The above-mentioned conventional technology drives the oil pump motor, which consumes a large amount of power, for hair ring lubrication even in running conditions where the temperature of the electric motor does not rise and oil cooling is not required. and consideration has been given to energy saving.
There was a problem that the charging distance was shortened.

A first object of the present invention is to provide an electric vehicle that consumes less power and can travel over a long charging distance.

Furthermore, in the above prior art, an oil pan is provided below the electric motor to collect oil for cooling. This required a space to install the oil pan, which posed a problem in terms of utilizing the limited space.

A second object of the present invention is to provide an electric vehicle that can effectively utilize space, which is an important issue in electric vehicles.

Furthermore, the above-mentioned conventional technology does not take into consideration the prevention of hair link seizure, and there is a problem in terms of safety.

A third object of the present invention is to provide an electric vehicle in which bearing seizure can be avoided.

Furthermore, a fourth object is to provide an electric vehicle that can supply oil for cooling other parts when the pump motor for supplying oil for cooling to the bearings of the electric mechanism stops operating. The purpose is to

[Means for solving problems]

In order to achieve the first object, the oil supply pump motor is configured to restrict operation when the temperature of the electric motor is low in order to supply cooling oil.

In order to achieve the second object, an oil recovery pump motor is provided to recover oil for cooling the electric mechanism.

In order to achieve the third objective, a pressure detector is provided to detect the pressure of oil supplied to the electric mechanism, and the electric mechanism is configured to not rotate when the pressure of cooling oil is below a predetermined level. .

In addition, in order to achieve the fourth objective of item 2, a mechanism is provided in which part of the oil for cooling the motor part of the electric mechanism can be used for lubrication of the hair ring. Configured.

[Effect]

According to the first configuration, the oil supply pump motor that supplies oil to the electric motor for cooling operates only when the temperature of the electric motor increases as determined by the temperature detector attached to the electric motor. Therefore, the i+b supply pump motor does not operate in a running state in which the electric motor does not exhibit thermal stress. Therefore, power consumption can be reduced,
Helps save energy and can extend charging distance.

According to the second configuration, the oil for cooling the electric drive mechanism;
The oil is sucked out from inside the electric motor by the operation of the recovery pump motor, and the electric mechanism is operated when the pump motor that supplies this oil is operated.

This makes it possible to eliminate the oil pan that is installed at the bottom of the electric motor to temporarily store oil, which helps to effectively utilize the limited space of the vehicle, and also reduces the overall amount of oil. , it becomes lighter.

Furthermore, this eliminates the possibility of oil remaining in the motor, thereby reducing oil agitation losses due to the rotating parts of the motor.

According to the third configuration, for example, the pressure detector attached to the bearing lubricant circulation piping detects the pressure of the oil for cooling. Furthermore, the electric mechanism does not operate unless the pressure of this oil exceeds a predetermined level. This prevents the motor from starting and the bearings from seizing up.

According to the fourth configuration, when an abnormality occurs in the bearing lubricant circulation system, such as when the bearing lubricant circulation oil pump motor does not operate or the lubricant oil pressure does not rise, the driving motor cooling system some of the oil,
A valve is switched and used for bearing lubrication. As a result, even if a problem occurs in the bearing lubricating oil circulation system and the vehicle stops, the vehicle will continue to run without the bearings seizing up, even if the vehicle is forced to continue running. be able to.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG. 1st
The figure is a block diagram of an oil cooling system for an electric vehicle equipped with two induction motors.

The lubricating oil that lubricates the bearings of the traveling induction motors La, ], b is sucked up from the oil tank 2 by an oil pump 4a driven by a lubricating oil supply pump motor 3a, and then supplied to the induction motor 1a.

1b to lubricate the bearings. The oil pressure of this lubricating oil is adjusted by a relief valve 5.

When the lubricating oil supply pump motor 3a starts, the lubricating oil recovery pump motor 3b is started in conjunction with this, and the lubricating oil is sent back to the oil tank 2 via the filter 10 by the oil pump 4b.

Cooling oil for cooling the coils of the induction motors 1a and lb is sucked from an oil tank 2' by an oil pump 4c driven by a cooling oil supply pump motor 3c, and passes through a radiator 7 via a check valve 6. During this time, it is cooled by a cooling fan 8 and sent to the induction motors 1a and lb. The oil pressure of this cooling oil is adjusted by a relief valve 9.

When the cooling oil supply pump motor 3c is activated, the cooling oil recovery pump motor 3d is activated in conjunction with this, and the oil pump 4d sends the cooling oil back to the oil tank 2 via the filter 10.

When the lubricating oil supply pump motor 3a starts, the pressure inside the lubricating oil system piping increases, which causes the pressure switch 1 to
1 is turned on. The temperature of the lubricating oil after lubricating the bearing is measured by a temperature sensor 12a.

12b.

A part of the cooling oil can be used for bearing lubrication by switching the valve 13 operated by a solenoid. FIG. 2 shows a system installed in a vehicle. In this system, the operation of the control circuit 15 will be explained using the flowcharts shown in FIGS. 3 and 4. First, in step 302, when the key switch 16 is turned on, the signal S is input to the control device 15.

As a result, in step 304, switches 1 and 7a are turned on to start the bearing lubricating oil supply pump motor 3a, current 1a flows from the battery 18, bearing link lubrication is started, and the pressure inside the pipe increases. Note that this turns on the pressure switch 11, and its signal p enters the control device]5.

When the bearing lubricating oil supply pump motor 3a operates, the switch 17b is turned on in conjunction with this in step 304, current ib flows from the battery 18, and the lubricating oil recovery pump motor 3b is activated. At step 312,
Based on this signal p, it is determined whether or not the bear link is being lubricated.

If the bearings have been lubricated, the running main circuit can be turned on in step 314 (running main circuit standby). At this time, if the pressure in the piping does not rise and bearing lubrication is not performed, press the pressure switch 1.
1 remains off, the signal p is not output. If this signal p does not enter the control device 15, the bearing seizing prevention protection circuit is activated to disable the main circuit of the drive system in step 34.0 shown in FIG. 4 (main circuit of the drive system 1~) .

By the way, as the vehicle travels, the temperature of the coils of the induction machines], a, and lb rises. When the temperature of the induction motor reaches the set temperature, the signals ta from the coil temperature detectors 12a and 12b,
tb enters the control circuit 15. When it is determined in step 316 that the temperature of the induction motor is less than the set temperature, in step 310 the switches 17c and 17d are turned on to draw current from the battery 8. , ]d flows, and the induction motor cooling oil supply oil pump 3c is started.Furthermore, in step 320, the induction motor cooling oil recovery foil pump 3d is started.

As a result, the oil in the oil tank 2 is circulated, and the induction motor 1. a. Cool lb. After this, the process proceeds to step 330 shown in FIG.

If the temperature of the lubricating oil after bearing lubrication rises abnormally,
The oil temperature sensors 12a, 1.2b detect this and send the signals Oa, Bb to the control device 15.

When it is determined in step 330 that the bearing is abnormally heated based on the signals Oa and eb, step 3
4.0, the protection circuit that controls the direction in which the vehicle is stopped is activated to prevent the hair ring from seizing in advance (
driving main circuit shut).

Note that when the power of the hydraulic system of the Hairing lubrication system goes down, the vehicle is stopped by a signal from the pressure switch 11. However, if an emergency situation is determined in step 332, but the vehicle is forced to continue driving, for example, the vehicle may stop in a dangerous area such as a railroad crossing or an intersection, and the vehicle may If it is necessary to move the vehicle to a safe location, in step 334, the switching valve 13, which is switched by the solenoid 1~, is operated. As a result, part of the cooling oil system 411 is used for bearing lubrication, and the vehicle can be driven. Furthermore, if the rotational speed of the induction motor is equal to or higher than a predetermined value in step 336, frequency control is performed in step 338 to suppress the rotational speed of the induction motors 1a, 1a, 1b, to the extent that the bearing' does not seize.

According to this embodiment, the oil pump for circulating bearing lubricating oil is operated by turning on the key switch of the vehicle, and is always in operation while the key switch is in the on state. Further, the oil pump for circulating the cooling oil for the traveling electric motor operates only when the temperature of the traveling electric motor increases in response to a signal from a temperature sensor for detecting a coil temperature attached to the traveling electric motor. As a result, in running conditions where the temperature of the electric motor does not rise, only the bearing lubrication oil pump, which consumes less power, operates, and the motor cooling oil pump, which consumes relatively more power, does not operate, reducing power consumption. This helps save energy and increases the charging distance.

Furthermore, when the operating mode is such that the coil temperature of the traveling electric motor does not reach TR, the noise is relatively low, so that the oil pump noise is at a level that is noticeable. At this time, only the small-capacity oil pump for bearing lubrication operates, and the large-capacity electric motor for driving does not operate, which helps reduce noise.

In order to collect the oil after cooling the driving electric motor and the oil after bearing lubrication into the oil tank, the oil is sucked out from inside the driving electric motor by separate oil pumps.
The pump motors that drive these pumps are operated only when the pump motors that supply the respective pumps 411 are operated.

As a result, it is possible to eliminate the oil pan that is installed at the bottom of the driving electric motor to store oil, which helps to make effective use of the limited space of the vehicle, and also reduces the overall amount of oil. It becomes lighter.

Furthermore, this eliminates the possibility of oil remaining in the traveling electric motor, thereby reducing oil agitation loss caused by the rotating portion of the traveling electric motor.

The pressure switch installed in the bearing lubricating oil circulation piping is turned on when the bearing lubricating oil circulation oil pump is started and the oil pressure in the piping reaches kPI. From this, it can be determined that the hair ring is lubricated. When the vehicle's key switch is turned on, the bearing lubrication oil pump is activated. The main circuit for running the vehicle is turned on by the ON signals from both the key switch and the pressure switch, and the main circuit is not operated when the pressure switch is not turned on. As a result, if the bearings are not lubricated, the electric motor for driving will not start, so the bearings will not seize.

Furthermore, a temperature sensor attached to the bearing lubricating oil circulation system detects the temperature of the oil after bearing lubrication. This makes it possible to detect abnormal heat generation in the bearing.
Bearing seizure can be prevented in advance.

If an abnormality occurs in the bearing lubricating oil circulation system, such as the oil pump motor for circulating the bearing lubricating oil not working or the oil pressure of the lubricating oil not rising, change the valve for part of the oil in the driving motor cooling system. The structure is such that it can be used for bearing lubrication. As a result, even if an abnormality occurs in the bearing lubricating oil circulation system and the vehicle stops, even if a situation arises in which the vehicle must continue running.

The vehicle can be driven without the bearings seizing up.

〔Effect of the invention〕

According to the first invention, in an electric vehicle using a high-speed rotation induction motor, an electric vehicle is realized that can reduce power consumption and can be cooled and lubricated. This has the effect of increasing mileage.

According to the second invention, since a pump motor for oil recovery is provided to recover the cooling oil of the electric motor, there is no need for space for installing a foil pan, and the effect is that the limited space inside the car can be used effectively. can get.

According to the third invention, when the pressure switch is turned on, the main circuit for driving the vehicle is turned on, and therefore,
When the hair ring is lubricated, the traction motor is started. Therefore, it is possible to avoid seizure of the bearing.

In the fourth invention, even when the first oil motor for lubricating the bearing is not operating, it is possible to supply oil to the bearing.

[Brief explanation of the drawing]

FIG. 1 is a configuration block diagram of the oil circulation system of the present invention,
FIG. 2 is a block diagram of an embodiment of the present invention installed in a vehicle, and FIGS. 3 and 4 are flowcharts showing the operation of the control circuit. la, lb... Induction motor for running, 2... Oil tank, 3 a, 3 b, 3 c, 3 d
...Pump motor.

Claims (1)

[Claims] 1. A battery, an electric motor connected to the battery,
A vehicle comprising wheels driven by the electric motor and an oil supply pump motor for supplying oil for cooling to the electric motor, further comprising temperature detection means for detecting the temperature of the electric motor, An electric vehicle characterized in that the electric vehicle is configured to limit operation of the oil supply pump motor when the temperature is below a predetermined temperature. 2. A device comprising a battery, an electric mechanism that rotates using the battery as a power source, wheels driven by the electric mechanism, and an oil supply pump motor that supplies oil for cooling to the electric mechanism. An electric vehicle comprising an oil recovery pump motor that recovers oil supplied for cooling the electric mechanism. 3. A vehicle comprising a battery, an electric mechanism that rotates using the battery as a power source, wheels driven by the electric mechanism, and an oil supply pump that supplies oil for cooling to the electric mechanism, It has a pressure detection means for detecting the pressure of oil supplied for cooling the electric mechanism, and is configured such that the electric mechanism does not rotate when the pressure of the supplied oil is below a predetermined value. electric car. 4. In a device comprising a battery, an electric mechanism that rotates using the battery as a power source, and wheels driven by the electric mechanism, a first valve for supplying oil for cooling the motor section of the electric mechanism. a second passage for supplying oil for cooling the bearings of the electric mechanism, and a valve that communicates the first passage with the second passage; An electric vehicle characterized in that the valve is configured to open and close.