JP6155686B2 - Solenoid valve control device - Google Patents

Description

  The present invention relates to a solenoid valve control device that controls a solenoid valve that performs hydraulic control of an automatic transmission mounted on a vehicle.

  Conventionally, vehicles equipped with an automatic transmission that automatically changes the gear ratio have been used. The automatic transmission changes the gear ratio using the pressure of hydraulic oil (hereinafter referred to as “hydraulic pressure”). Such hydraulic pressure is controlled by a hydraulic circuit having various valves. As one of such valves, a solenoid valve whose opening degree can be adjusted electrically is used. Such adjustment of the opening degree of the solenoid valve is performed by changing the current flowing through the solenoid. For this reason, it is necessary to accurately control the current flowing through the solenoid in order to appropriately operate the automatic transmission, for example, to reduce a shock at the time of shifting. As a technique used for such control, there is a technique described in Patent Document 1 that exhibits the following.

  In the technique described in Patent Document 1, the current flowing through the solenoid is controlled by DUTY control, and the feedback control is performed by comparing the indicated current value and the current value of the actual current flowing through the solenoid.

JP 2011-52737 A

  As in the technique described in Patent Document 1, in order to control the current flowing through the solenoid by feedback control, it is necessary to accurately measure the current flowing through the solenoid. However, such a current measurement circuit that measures current includes, for example, variations in constants of components that constitute the current measurement circuit and errors due to variations in temperature characteristics. Once the variation in the constants of the parts is corrected, it is less likely to fluctuate thereafter, but the temperature characteristics are not easily corrected over the operating temperature range of the product. Therefore, it is conceivable to use a thermistor to correct the temperature characteristic. However, the thermistor is expensive and increases the cost of the product.

  In view of the above problems, an object of the present invention is to provide a solenoid valve control device capable of accurately controlling a current flowing through a solenoid without increasing the cost.

In order to achieve the above object, the characteristic configuration of the solenoid valve control device according to the present invention is as follows:
A current measuring unit that measures a current flowing through a solenoid that drives a solenoid valve that performs hydraulic control of an automatic transmission mounted on the vehicle;
A storage unit for storing the temperature of the current measuring unit at the time of the previous stop of the automatic transmission;
An elapsed time information acquisition unit for acquiring elapsed time information indicating the elapsed time from the previous operation stop to the present time;
A temperature calculation unit that calculates a current temperature of the current measurement unit based on the temperature of the current measurement unit and the elapsed time information at the time of the previous shutdown;
When restarting the operation of the automatic transmission , based on the temperature fluctuation characteristics of the current measurement unit, the required oil pressure and the current temperature of the current measurement unit calculated and the environmental temperature of the place where the current measurement unit is installed In consideration of the above , there is provided an energization control unit that energizes the solenoid so as to eliminate the temperature drift included in the measurement result of the current measurement unit .

  As in this configuration, the current temperature of the current measurement unit is calculated based on the temperature of the current measurement unit at the time of shutdown and the elapsed time from the time of shutdown to the present. Even so, the current flowing through the solenoid can be accurately controlled. In calculating the current temperature of the current measuring unit, for example, when the current measuring unit is installed in the vehicle, the detection result of the in-vehicle temperature sensor can be used. When installed in a room, the detection result of the temperature sensor outside the vehicle can be used, so there is no cost increase. Therefore, the solenoid valve control device can be configured at low cost.

Further, the elapsed time information acquisition unit, the temperature difference between the temperature of the hydraulic oil and the current hydraulic oil temperature at the time of the previous operation stop of the automatic transmission, the outside air temperature measured by the outside temperature sensor, It is preferable that the elapsed time is calculated using a relationship between the temperature gradient and the outside air temperature when the temperature of the hydraulic oil is reduced in advance .

  Usually, an oil temperature sensor for measuring the temperature of the hydraulic oil of the automatic transmission is provided. By associating the decreasing tendency of the oil temperature with the elapsed time from the stop of the operation to the present, the elapsed time can be calculated based on the detection result of the oil temperature sensor. For this reason, since there is no separate counter for measuring the elapsed time, there is no need to increase the cost. Therefore, a solenoid valve control device can be realized at low cost.

A temperature update unit that updates the temperature of the current measurement unit stored in the storage unit with the temperature calculated by the temperature calculation unit;
A calorific value calculating unit that calculates a calorific value of the current measuring unit based on an operating state of the automatic transmission during operation of the automatic transmission; and
After resuming operation of the automatic transmission, the energization control unit eliminates the temperature drift based on the required oil pressure, the updated temperature of the current measurement unit, and the calculated calorific value of the current measurement unit. Thus, it is preferable to energize the solenoid.

  If the solenoid is energized in this way, the current measuring unit can accurately measure the current flowing through the solenoid even during the operation (operation) of the automatic transmission. Therefore, the current flowing through the solenoid can be accurately controlled.

The temperature variation characteristic of the current measuring unit is provided characteristic storage section is stored in advance, the power supply controller includes said temperature variation also be considered in accordance with the environmental temperature in which the current measuring unit is installed Temperature It is preferable to energize the solenoid so as to eliminate drift .

  With such a configuration, variations in measurement results due to temperature fluctuations in the current measuring unit can be eliminated. Therefore, even when the environmental temperature changes, the current flowing through the solenoid can be measured with high accuracy, and thus the current can be appropriately controlled.

It is a schematic diagram which shows the structure and function of a solenoid valve control apparatus. It is a figure which shows the example which acquires elapsed time information based on oil temperature. It is a figure which shows the example which acquires elapsed time information based on oil temperature. It is a figure which shows the example of the temperature fluctuation characteristic of an electric current measurement part. It is a figure which shows the difference in the emitted-heat amount according to a control state. It is a figure which shows the example which calculates the emitted-heat amount according to a control state.

  The solenoid valve control device according to the present invention is configured to have a function of accurately controlling the current flowing through the solenoid that drives the solenoid valve. Hereinafter, the solenoid valve control device 100 of the present embodiment will be described in detail. FIG. 1 is a schematic diagram showing the configuration and function of the solenoid valve control device 100. As shown in FIG. 1, the solenoid valve control device 100 includes a temperature determination unit 11, an elapsed time information acquisition unit 12, a temperature calculation unit 13, a storage unit 14, a temperature update unit 15, a heat generation amount calculation unit 16, and an energization control unit. 17, the current measurement unit 18, and the characteristic storage unit 19. Each function unit has a CPU as a core member, and the above-described function units for performing various processes for accurately controlling the current flowing through the solenoid are constructed by hardware and / or software. Here, in the present embodiment, an example in which each functional unit described above is configured by one ECU (Electronic Control Unit) and the ECU is provided in the vehicle will be described.

  The temperature determination unit 11 determines whether or not there is a difference between the current vehicle outside temperature and the current oil temperature when a driving instruction is given to the automatic transmission 50 that is stopped (# 01). ). The automatic transmission 50 is a transmission that is mounted on a vehicle and has a function of automatically switching a gear ratio according to the vehicle speed of the vehicle and the rotational speed of the engine. The operation of the automatic transmission 50 is controlled using hydraulic pressure. The vehicle outside temperature is the temperature outside the vehicle compartment, that is, the outside air temperature. The vehicle outside temperature is measured and transmitted by a vehicle outside temperature sensor 71 constituting the sensor group 70. The oil temperature is the temperature of hydraulic oil that generates hydraulic pressure that controls the operation of the automatic transmission 50 described above. The oil temperature is measured and transmitted by an oil temperature sensor 72 constituting the sensor group 70. The vehicle outside temperature sensor 71 and the oil temperature sensor 72 may not be included in the solenoid valve control device 100, and those generally provided in the vehicle can be used.

  When the difference between the current outside temperature and the current oil temperature is small (for example, less than 10 ° C.) by the temperature determination unit 11 (# 02), the determination result is transmitted to the temperature calculation unit 13. The In such a case, the temperature calculation unit 13 determines that the automatic transmission 50 has been stopped for a long time, and calculates the in-vehicle temperature as the temperature of the current measurement unit 18 (# 03). The vehicle interior temperature is the temperature in the passenger compartment. The in-vehicle temperature is measured and transmitted by an in-vehicle temperature sensor 73 constituting the sensor group 70. The in-vehicle temperature sensor 73 does not have to be provided in the solenoid valve control device 100, and it is possible to use what is generally provided in the vehicle.

  On the other hand, when the difference between the current vehicle outside temperature and the current oil temperature is large (for example, 10 ° C. or higher) by the temperature determination unit 11 (# 04), the determination result is an elapsed time information acquisition unit. 12 is transmitted.

  In this case, the elapsed time information acquisition unit 12 acquires elapsed time information indicating the elapsed time from the previous operation stop to the present time. The time of the previous operation stop is the time of the previous operation stop of the automatic transmission 50. That is, it means the time when the ignition key is turned off (when the ignition button is provided, the time when the ignition button is turned off). Therefore, the elapsed time information acquisition unit 12 acquires elapsed time information indicating the time elapsed from when the ignition key is turned off to the present.

  In the present embodiment, the elapsed time information acquisition unit 12 calculates the elapsed time based on the temperature of the hydraulic oil when the automatic transmission 50 was last stopped and the current temperature of the hydraulic oil. As described above, the automatic transmission 50 is controlled by hydraulic pressure. The temperature of the hydraulic oil that generates the hydraulic pressure is transmitted from the above-described oil temperature sensor 72 (# 05). In the present embodiment, the outside temperature of the outside temperature sensor 71 is also transmitted to the elapsed time information acquisition unit 12. The temperature of the hydraulic oil at the time of the previous operation stop is stored in the storage unit 14 described later. The current temperature of the hydraulic oil is the temperature of the hydraulic oil when the operation (for example, operation) of the automatic transmission 50 is resumed. When the operation of the automatic transmission 50 is resumed, the elapsed time information acquisition unit 12 acquires the temperature of the hydraulic fluid at that time from the oil temperature sensor 72 and the operation of the automatic transmission 50 is stopped from the storage unit 14. The temperature of the hydraulic oil at the time is acquired (# 06).

  The storage unit 14 stores the temperature of the current measurement unit 18, the temperature outside the vehicle, the temperature inside the vehicle, and the oil temperature when the automatic transmission 50 was stopped last time. The previous stop of the automatic transmission 50 is when the ignition key is turned off as described above. Here, in the solenoid valve control apparatus 100, the temperature of the current measuring unit 18 is not actually measured by a thermometer or the like, but is calculated by calculation using various parameters. This calculation will be described later. A measurement result is transmitted from the vehicle outside temperature sensor 71, a measurement result is transmitted from the vehicle temperature sensor 73, and a measurement result is transmitted from the oil temperature sensor 72 to the oil temperature. The storage unit 14 stores the respective temperatures when the automatic transmission 50 is stopped (# 07).

  The elapsed time information acquisition unit 12 calculates the temperature difference between the oil temperature at the time of the previous stoppage of the automatic transmission 50 stored in the storage unit 14 and the current oil temperature (# 08). Here, when the time from when the previous operation is stopped to when the operation is resumed is sufficiently long, the temperature of the hydraulic oil when the operation of the automatic transmission 50 is resumed matches the outside air temperature as shown in FIG. . On the other hand, when the time from when the previous operation is stopped to when the operation is resumed is relatively short, the temperature of the hydraulic oil when the operation of the automatic transmission 50 is resumed is different from the outside air temperature as shown in FIG. .

  The temperature gradient when the temperature of the hydraulic fluid is lowered is determined by the heat radiation characteristics of the hydraulic circuit system and the outside air temperature. Here, the heat dissipation characteristics of the hydraulic circuit system are substantially equal if the type of the automatic transmission 50 is the same. For this reason, there is no problem considering that the temperature gradient of the hydraulic oil is defined by the outside air temperature. Therefore, it is preferable to create a map that defines the relationship between the hydraulic pressure gradient and the outside air temperature in advance using an actual machine and store the map in the elapsed time information acquisition unit 12. The elapsed time information acquisition unit 12 uses the temperature difference of the hydraulic oil at the two points obtained as described above, the map, and the outside air temperature to calculate the time from when the operation of the automatic transmission 50 is stopped until it is restarted. It is possible to calculate. As the outside air temperature, the outside temperature transmitted from the outside temperature sensor 71 as described above is used.

  The temperature calculation unit 13 calculates the current temperature of the current measurement unit 18 based on the temperature of the current measurement unit 18 and the elapsed time information at the previous stop of operation. The temperature of the current measurement unit 18 at the time of the previous operation stop is stored in the storage unit 14 as described above, and is transmitted to the temperature calculation unit 13 (# 09). The elapsed time information is acquired by the elapsed time information acquisition unit 12 and transmitted to the temperature calculation unit 13 (# 10). The temperature calculation unit 13 calculates the heat radiation amount from these two pieces of information, and calculates the current temperature of the current measurement unit 18 (# 03).

  Here, the temperature storage characteristic of the current measurement unit 18 is stored in the characteristic storage unit 19 in advance. That is, the measurement result of the current measuring unit 18 includes temperature drift. Such a temperature drift becomes a measurement error of the current measuring unit 18. For this reason, when considering controlling the solenoid valve 30 with high accuracy, it is desirable to eliminate such temperature drift. Therefore, in the present embodiment, when the solenoid valve control device 100 is mounted on the vehicle, the characteristic storage unit 19 stores the temperature fluctuation characteristic measured by an actual device by changing the temperature. The accuracy of the temperature fluctuation characteristics is improved when the temperature fluctuation characteristics are stored in each solenoid valve control device 100 by changing the temperature in the inspection of the solenoid valve control device 100 at the time of shipment from the factory. An example of such temperature variation characteristics is shown in FIG. In the example of FIG. 4, the variation rate increases as the temperature decreases, and the variation rate decreases as the temperature increases. Depending on the characteristics of the current measuring unit 18, the rate of change decreases as the temperature decreases, and the rate of change increases as the temperature increases. The rate of change is constant within a predetermined temperature range. There are also things. Such temperature fluctuation characteristics are stored in the characteristic storage unit 19.

  The current measuring unit 18 measures the current flowing through the solenoid 31 that drives the solenoid valve 30 that controls the hydraulic pressure of the automatic transmission 50 mounted on the vehicle (# 11). As described above, the operation of the automatic transmission 50 is controlled using hydraulic pressure, and the hydraulic pressure is controlled using the known solenoid valve 30. The solenoid valve 30 energizes the solenoid 31 to function as an electromagnet, and moves the plunger by the magnetic force to change the opening of the valve. The opening degree of the valve can be changed by the current flowing through the solenoid 31. The current measuring unit 18 measures the current flowing through the solenoid 31. In FIG. 1, only one solenoid 31 is shown for easy understanding, but a plurality of solenoid valves 30 may be provided in the automatic transmission 50. In such a case, each current is measured by the current measuring unit 18.

  The energization control unit 17 energizes the solenoid 31 based on the required oil pressure and the calculated current temperature of the current measurement unit 18 when resuming the operation of the automatic transmission 50. The required oil pressure is the oil pressure required from the host system depending on the position of the shift lever that selects the gear of the automatic transmission 50. This required oil pressure is the base of the magnitude of the current that flows through the solenoid 31. The current temperature of the current measuring unit 18 is calculated and transmitted by the temperature calculating unit 13.

  In the present embodiment, the energization control unit 17 energizes the solenoid 31 in consideration of temperature fluctuations according to the environmental temperature in which the current measurement unit 18 is installed (# 12). As described above, the current measuring unit 18 has a temperature drift according to the temperature. Therefore, the energization control unit 17 energizes in consideration of the temperature drift according to the environmental temperature where the current measurement unit 18 is installed. Here, in the present embodiment, the current measuring unit 18 is provided in the vehicle. Accordingly, the in-vehicle temperature is transmitted from the in-vehicle temperature sensor 73 to the energization control unit 17, and the variation rate corresponding to the temperature is acquired from the characteristic storage unit 19.

  Here, the energization control unit 17 controls the current flowing through the current measurement unit 18 by known PWM control. Therefore, the DUTY value of the PWM signal corresponding to the required oil pressure is set, and the DUTY value is adjusted according to the current temperature of the current measuring unit 18 and the environmental temperature. Since the current supplied to the solenoid 31 is adjusted in this way, the solenoid valve 30 can be controlled with high accuracy, and the automatic transmission 50 can be driven.

  Here, the control of the automatic transmission 50 needs to be performed with high accuracy not only when the operation is resumed but also during the subsequent operation. Therefore, the solenoid valve control device 100 is configured to be able to appropriately control the current supplied to the solenoid 31 even after such operation restart.

  Also in this case, the energization control unit 17 controls the current flowing through the solenoid 31 by adjusting the DUTY value according to the current temperature and the environmental temperature of the current measurement unit 18. Here, the temperature of the current measuring unit 18 calculated by the temperature calculating unit 13 when the operation of the automatic transmission 50 is resumed is transmitted to the temperature updating unit 15. The temperature update unit 15 updates the temperature of the current measurement unit 18 stored in the storage unit 14 with the temperature calculated by the temperature calculation unit 13 (# 13). The temperature of the current measuring unit 18 stored in the storage unit 14 is the temperature of the current measuring unit 18 when the automatic transmission 50 is restarted when the automatic transmission 50 is restarted, and during the operation of the automatic transmission 50. Is the temperature updated by the temperature update unit 15. The temperature calculated by the temperature calculation unit 13 is transmitted from the temperature calculation unit 13. The temperature update unit 15 updates the temperature of the current measurement unit 18 stored in the storage unit 14 with such a temperature.

  The calorific value calculation unit 16 calculates the calorific value of the current measurement unit 18 based on the operating state of the automatic transmission 50 during operation of the automatic transmission 50 (# 14). “During the operation of the automatic transmission 50” means a state in which the automatic transmission 50 is continuously operated after the operation of the automatic transmission 50 is resumed. The operating state of the automatic transmission 50 corresponds to the number of gear stages set by the automatic transmission 50. Here, the temperature of the ECU increases according to the number of gears, and the temperature of the current measuring unit 18 also increases accordingly. It is preferable that the relationship between the number of gear stages and the temperature rise is stored in advance in the calorific value calculation unit 16 as a map.

  FIG. 5 shows an example of such a map. In the example of FIG. 5, the vertical axis is defined by the rising temperature and the horizontal axis is defined by the time. It is shown that the temperature gradient gradually decreases as the gear stage of the automatic transmission 50 changes from the first speed to the fifth speed.

  The calorific value calculation unit 16 receives driving information including information on the gear currently in use from the host system according to the traveling of the vehicle. The calorific value calculation unit 16 calculates the calorific value of the current measurement unit 18 using the operation information and the map.

  FIG. 6 shows the heat generation amount of the current measurement unit 18 calculated by the heat generation amount calculation unit 16. Since the vehicle traveled at the first speed from t0 to t1, heat is generated with the temperature gradient of the first speed in FIG. Since the vehicle was traveling at the 2nd speed from t1 to t2, the heat generation amount was accumulated at the temperature gradient of the 2nd speed in FIG. 5, and the vehicle was traveling at the 3rd speed from t2 to t3. The calorific value is accumulated with the temperature gradient. Further, since the vehicle traveled at the 4th speed from t3 to t4, the calorific value was accumulated at the temperature gradient of the 4th speed in FIG. 5 and traveled at the 5th speed after t4. The calorific value is accumulated with a gradient. In this way, the calorific value calculation unit 16 calculates the calorific value of the current measurement unit 18. This calculation result is transmitted to the energization control unit 17.

  The energization control unit 17 energizes the solenoid 31 based on the required oil pressure, the updated temperature of the current measurement unit 18, and the calculated temperature of the current measurement unit 18 after restarting the operation of the automatic transmission 50 (# 12). The required oil pressure is a necessary oil pressure transmitted from the host system as described above. The updated temperature of the current measuring unit 18 is the temperature of the storage unit 14 updated by the temperature updating unit 15. The calculated temperature of the current measuring unit 18 is a temperature calculated by the calorific value calculating unit 16. The energization control unit 17 controls the current flowing through the solenoid 31 in consideration of these temperatures.

[Other Embodiments]
In the above embodiment, the elapsed time information acquisition unit 12 has been described as calculating the elapsed time based on the temperature of the hydraulic oil and the current temperature when the automatic transmission 50 was last stopped. However, the scope of application of the present invention is not limited to this. Of course, the elapsed time information acquisition unit 12 may acquire the counting result of a counter that counts the time since the automatic transmission 50 stopped operating, and calculate the elapsed time. Specifically, the counting result may be acquired from a power management control device (not shown) that reduces the power loss of the battery, or another counter may be mounted to acquire the counting result. Is possible. Furthermore, it is naturally possible to provide the elapsed time information acquisition unit 12 with a counter function.

  In the above embodiment, the energization control unit 17 restarts the operation of the automatic transmission 50, and then the requested oil pressure, the updated temperature of the current measurement unit 18, and the heat generation of the current measurement unit 18 calculated by the heat generation amount calculation unit 16. The solenoid 31 was energized based on the amount. However, the scope of application of the present invention is not limited to this. Naturally, the energization control unit 17 may be configured to energize the solenoid 31 based only on the required hydraulic pressure after the automatic transmission 50 is restarted. In addition, the energization control unit 17 is one of the required oil pressure, the updated temperature of the current measuring unit 18 and the calorific value of the current measuring unit 18 calculated by the calorific value calculating unit 16 after restarting the operation of the automatic transmission 50. Of course, it is also possible to energize the solenoid 31 based on one of them.

  In the above embodiment, the energization control unit 17 has been described as energizing the solenoid 31 in consideration of temperature fluctuations according to the calculated temperature of the current measurement unit 18. However, the scope of application of the present invention is not limited to this. Naturally, the energization control unit 17 may be configured to energize the solenoid 31 without considering the temperature variation of the current measurement unit 18.

  In the embodiment described above, the temperature determination unit 11 has been described as determining whether or not the difference between the current vehicle exterior temperature and the current oil temperature is less than 10 ° C., for example. However, the scope of application of the present invention is not limited to this. 10 ° C. is merely an example, and it is naturally possible to set it to another temperature.

  The present invention can be used for a solenoid valve control device that controls a solenoid valve that performs hydraulic control of an automatic transmission mounted on a vehicle.

12: Elapsed time information acquisition unit 13: Temperature calculation unit 14: Storage unit 15: Temperature update unit 16: Heat generation amount calculation unit 17: Energization control unit 18: Current measurement unit 19: Characteristic storage unit 30: Solenoid valve 31: Solenoid 50 : Automatic transmission 100: Solenoid valve control device

Claims (4)

A current measuring unit that measures a current flowing through a solenoid that drives a solenoid valve that performs hydraulic control of an automatic transmission mounted on the vehicle;
A storage unit for storing the temperature of the current measuring unit at the time of the previous stop of the automatic transmission;
An elapsed time information acquisition unit for acquiring elapsed time information indicating the elapsed time from the previous operation stop to the present time;
A temperature calculation unit that calculates a current temperature of the current measurement unit based on the temperature of the current measurement unit and the elapsed time information at the time of the previous shutdown;
When restarting the operation of the automatic transmission , based on the temperature fluctuation characteristics of the current measurement unit, the required oil pressure and the current temperature of the current measurement unit calculated and the environmental temperature of the place where the current measurement unit is installed In consideration of the above, an energization control unit that energizes the solenoid so as to eliminate the temperature drift included in the measurement result of the current measurement unit ,
A solenoid valve control device comprising: The elapsed time information acquisition unit is created in advance, the temperature difference between the temperature of the hydraulic oil and the current hydraulic oil temperature at the time of the previous operation stop of the automatic transmission, the outside air temperature measured by the outside temperature sensor, 2. The solenoid valve control device according to claim 1, wherein the elapsed time is calculated using a relationship between a temperature gradient when the temperature of the hydraulic oil decreases and an outside air temperature . A temperature update unit that updates the temperature of the current measurement unit stored in the storage unit with the temperature calculated by the temperature calculation unit;
A calorific value calculating unit that calculates a calorific value of the current measuring unit based on an operating state of the automatic transmission during operation of the automatic transmission; and
After resuming operation of the automatic transmission, the energization control unit eliminates the temperature drift based on the required oil pressure, the updated temperature of the current measurement unit, and the calculated calorific value of the current measurement unit. The solenoid valve control device according to claim 1 , wherein the solenoid is energized as described above. A characteristic storage unit in which the temperature variation characteristic of the current measuring unit is stored in advance;
The energization control unit energizes the solenoid so as to eliminate the temperature drift in consideration of a temperature variation according to an environmental temperature in which the current measurement unit is installed. Solenoid valve control device.

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