JP2010196851A - Oil temperature control device of transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an oil temperature control device of a transmission capable of properly controlling the oil temperature of the transmission. <P>SOLUTION: This oil temperature control device 1 of the transmission is a device for controlling the oil temperature of the transmission by exchanging heat of lubricating oil of the transmission by a heat exchanger 2. The oil temperature control device of this transmission has a flow rate control part 3 for controlling a flow rate of the lubricating oil supplied to the heat exchanger 2. This flow rate control part 3 controls the flow rate of the lubricating oil supplied to the heat exchanger 2 based on a calorific value by a transmission loss. Thus, the flow rate of the lubricating oil in the heat exchanger 2 is actively controlled by the flow rate control part 3. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an oil temperature control device for a transmission, and more particularly to an oil temperature control device for a transmission that can appropriately control the oil temperature of the transmission.

  For example, in a continuously variable transmission for a vehicle, it is necessary to supply lubricating oil to each mechanism to properly lubricate or cool each mechanism. For this reason, recent oil temperature control devices for transmissions employ a configuration in which the oil temperature of the transmission is controlled by heat exchange of the lubricating oil of the transmission using a heat exchanger. As a conventional oil temperature control device for a transmission that employs such a configuration, a technique described in Patent Document 1 is known.

Japanese Patent Application Laid-Open No. 2004-339989

  An object of the present invention is to provide an oil temperature control device for a transmission that can appropriately control the oil temperature of the transmission.

  To achieve the above object, an oil temperature control device for a transmission according to the present invention is an oil for a transmission that controls the oil temperature of the transmission by performing heat exchange of lubricating oil of the transmission with a heat exchanger. A temperature control device comprising a flow rate control unit for controlling a flow rate of lubricating oil supplied to the heat exchanger, and the flow rate control unit controls the flow rate of the lubricating oil based on a heat generation amount due to transmission loss It is characterized by doing.

  In this oil temperature control device, a flow rate control unit that controls the flow rate of the lubricating oil supplied to the heat exchanger is provided, and this flow rate control unit controls the flow rate of the lubricating oil based on the amount of heat generated by transmission loss. In such a configuration, the flow rate of the lubricating oil in the heat exchanger is positively controlled by the flow rate control unit. Therefore, there is an advantage that the oil temperature of the transmission is appropriately controlled as compared with a configuration in which the amount of lubricating oil in the heat exchanger is not controlled.

  In the oil temperature control device according to the present invention, a flow rate control unit for controlling the flow rate of the lubricating oil supplied to the heat exchanger is provided, and this flow rate control unit controls the flow rate of the lubricating oil based on the heat generation amount due to transmission loss. To do. In such a configuration, the flow rate of the lubricating oil in the heat exchanger is positively controlled by the flow rate control unit. Therefore, there is an advantage that the oil temperature of the transmission is appropriately controlled as compared with a configuration in which the amount of lubricating oil in the heat exchanger is not controlled.

FIG. 1 is a block diagram showing an oil temperature control device for a transmission according to an embodiment of the present invention. FIG. 2 is a block diagram showing the operation of the oil temperature control device shown in FIG. FIG. 3 is a block diagram showing the operation of the first modification of the oil temperature transmission shown in FIG. FIG. 4 is a block diagram showing the operation of the modification 2 of the oil temperature transmission shown in FIG. FIG. 5 is a block diagram showing the operation of the second modification of the oil temperature transmission shown in FIG. FIG. 6 is a block diagram showing the operation of Modification 3 of the oil temperature transmission shown in FIG. FIG. 7 is a block diagram showing the operation of the modified example 4 of the oil temperature transmission shown in FIG.

  Hereinafter, the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments. Further, the constituent elements of this embodiment include those that can be replaced while maintaining the identity of the invention and that are obvious for replacement. In addition, a plurality of modifications described in this embodiment can be arbitrarily combined within a range obvious to those skilled in the art.

[Transmission oil temperature control device]
The transmission oil temperature control device 1 is a device for controlling the oil temperature of the lubricating oil of the transmission, and is applied to, for example, a belt type continuously variable transmission or a toroidal type continuously variable transmission for a vehicle (see FIG. 1).

  For example, in this embodiment, the secondary regulator valve 11 disposed in the drain-type lubrication oil passage, the lubrication system 12 and the rear side (for example, the torque converter, the forward / reverse switching device, etc.) in the transmission, for example, And a lubricating system 13 of a speed reduction mechanism or the like is connected through a lubricating oil passage 151. In addition, the lubricating oil passage in which the secondary regulator valve 11 and the lubricating system 14 of the transmission portion of the transmission (for example, the contact portion between the pulley and the belt of the belt type continuously variable transmission) are branched from the middle of the lubricating oil passage 151. 152 is connected. The oil temperature control device 1 is disposed on the lubricating oil passage 152 on the lubricating system 14 side of the transmission unit, and controls the oil temperature of the lubricating oil supplied to the lubricating system 14 of the transmission unit.

  The oil temperature control device 1 includes a heat exchanger 2, a flow rate control unit 3, and an ECU (electronic control unit) 4. The heat exchanger 2 is a device that cools (or heats) the lubricating oil by heat exchange, and includes, for example, an air-cooled cooler or a water-cooled cooler. The flow rate control unit 3 is a hydraulic circuit that controls the flow rate of the lubricating oil supplied to the heat exchanger 2, and has a linear solenoid valve as the flow rate control valve 31. Further, the heat exchanger 2 and the flow rate control unit 3 are arranged in series on the lubricating oil passage 152 on the lubricating system 14 side of the transmission unit. The ECU 4 performs a predetermined calculation based on output values from various sensors (not shown), and drives and controls the flow rate control unit 3 (flow rate control valve 31) based on the calculation result. Various sensors include, for example, a vehicle speed sensor that measures vehicle speed or wind speed, an outside air temperature sensor that measures the temperature of outside air, a T / M oil temperature sensor that measures the oil temperature (T / M oil temperature) of the transmission, and engine torque. A torque sensor for measuring, a rotation speed sensor for measuring the engine speed, a heat exchanger inlet oil temperature sensor for measuring the oil temperature of the lubricating oil at the inlet of the heat exchanger 2, and the like are included.

  In the oil temperature control device 1, the oil temperature of the lubricating oil of the transmission is controlled as follows. First, lubricating oil heated to a high temperature by transmission loss (T / M loss) heat flows into the lubricating oil passage 152 from the secondary regulator valve 11 and is supplied to the heat exchanger 2 through the flow rate control unit 3. . The lubricating oil is cooled by exchanging heat in the heat exchanger 2 and supplied to the lubricating system 14 of the transmission unit. At this time, the flow rate control unit 3 (flow rate control valve 31) is driven, and the flow rate of the lubricating oil in the heat exchanger 2 is controlled. Thereby, the oil temperature of the lubricating oil supplied to the lubricating system 14 of the transmission is controlled.

[Flow control of lubrication amount to heat exchanger]
Here, in the oil temperature control of the transmission described above, the required heat radiation amount in the heat exchanger 2 is calculated based on the heat balance, and the flow rate control unit 3 is driven based on the necessary heat radiation amount, so that the heat exchanger 2 The flow rate of the lubrication amount is controlled (see FIG. 2). Specifically, the following feedforward control is performed.

  First, the amount of heat generated due to torque converter loss (T / C loss), the amount of heat generated due to transmission loss (T / M loss), the amount of heat released due to surface heat dissipation of the transmission (T / M heat dissipation amount), and heat transfer from the engine Based on the sum of the amount of heat and the required heat dissipation amount (FF required heat dissipation amount) is calculated. This required heat dissipation is the amount of heat that needs to be radiated by the heat exchanger 2 in this feedforward control. The amount of heat generated by the torque converter s loss is calculated based on the engine torque, the engine speed, and the torque converter efficiency (T / C efficiency). Further, the heat generation amount due to the transmission loss is calculated based on the engine torque and the engine speed. The engine torque and the engine speed are acquired as output values of the engine torque sensor and the engine speed sensor. The heat radiation amount of the transmission is calculated based on the vehicle speed (wind speed), the outside air temperature, and the T / M oil temperature. The vehicle speed, the outside air temperature, and the T / M oil temperature are acquired as output values of the vehicle speed sensor, the outside air temperature sensor, and the T / M oil temperature sensor.

  Next, the target flow rate of the lubricating oil in the heat exchanger 2 is calculated based on the necessary heat release amount, the vehicle speed (wind speed), the outside air temperature, and the heat exchanger inlet oil temperature. This target flow rate is calculated based on a reverse map indicating the performance characteristics of the heat exchanger 2. In addition, the heat exchanger inlet oil temperature may be acquired as an output value of the heat exchanger inlet oil temperature sensor, or a value obtained from the output value of the T / M oil temperature sensor may be used.

  Next, based on this target flow rate and the line pressure solenoid command current, a target current (flow control solenoid target current) of the flow control valve 31 of the flow control unit 3 is calculated. This target current is calculated based on a reverse map indicating the flow characteristics of the flow control valve 31.

  The flow rate control valve 31 is driven based on this target current, and the flow rate of the lubrication amount in the heat exchanger 2 is controlled. As a result, the heat generated by the T / M loss is offset by the heat dissipation amount of the heat exchanger 2, and the oil temperature of the lubricating oil in the transmission is properly maintained.

[effect]
As described above, in the oil temperature control device 1, the flow rate control unit 3 that controls the flow rate of the lubricating oil supplied to the heat exchanger 2 is provided, and the flow rate control unit 3 is based on the amount of heat generated by transmission loss. Thus, the flow rate of the lubricating oil is controlled (see FIGS. 1 and 2). In such a configuration, the flow rate of the lubricating oil in the heat exchanger 2 is positively controlled by the flow rate control unit 3. Therefore, there is an advantage that the oil temperature of the transmission is appropriately controlled as compared with a configuration in which the amount of lubricating oil in the heat exchanger is not controlled.

  For example, a toroidal-type continuously variable transmission generally has a characteristic that the traction coefficient depends on the oil temperature and decreases under both low and high driving conditions. In this respect, in this oil temperature control device 1, (1) the oil temperature of the transmission can be controlled (oil temperature management) within a temperature range having a high traction coefficient. Therefore, in the toroidal continuously variable transmission, the power roller The hydraulic pressure for pressing the disc against the disc can be reduced. Thereby, there is an advantage that the driving efficiency of the transmission and the fuel consumption of the vehicle are improved, and there is an advantage that the durability performance of the transmission is improved.

  Further, (2) in the belt-type continuously variable transmission, since the oil temperature of the transmission can be controlled by annealing the belt below the temperature, there is an advantage that the durability performance of the transmission is improved.

  In addition, in the toroidal type continuously variable transmission, the lubricating oil (traction fluid) that is generally used is more easily evaporated than ATF (Automatic Transmission Fluid), so the upper limit of the operating temperature of AT (Automatic Transmission) is -20 ° C. Must be set to In this respect, the oil temperature control apparatus 1 has the advantage that (3) the oil temperature of the transmission can be controlled appropriately, and the evaporation amount of the lubricating oil can be suppressed.

  Moreover, in this oil temperature control apparatus 1, the target flow rate of the lubricating oil in the heat exchanger 2 is calculated based on a reverse map indicating the performance characteristics of the heat exchanger 2 (see FIG. 2). This reverse lookup map is a map for calculating the target flow rate of the lubricating oil in the heat exchanger 2 based on the required heat radiation amount in the heat exchanger 2, the vehicle speed (wind speed), the outside air temperature, and the heat exchanger inlet oil temperature. It is. Such a configuration has an advantage that the target flow rate in the heat exchanger 2 can be easily calculated.

  Further, in the oil temperature control device 1, the target current (flow control solenoid target current) of the flow control valve 31 of the flow control unit 3 is calculated based on the reverse lookup map indicating the flow characteristics of the flow control valve 31 ( (See FIG. 2). This reverse lookup map is a map for calculating the flow control solenoid target current based on the target flow rate in the heat exchanger 2 and the line pressure solenoid command current. Such a configuration has an advantage that the line pressure solenoid command current can be easily calculated.

[Modification 1]
In this oil temperature control device 1, the deviation between the current oil temperature of the transmission and the target oil temperature is calculated, and the necessary heat radiation amount in the heat exchanger 2 may be calculated based on this deviation (FIG. 3). reference). Then, the flow rate control unit 3 is driven based on the necessary heat radiation amount, and the flow rate of the lubrication amount in the heat exchanger 2 is controlled. Specifically, the following feedback control can be performed.

  First, in calculating the required heat dissipation amount in the heat exchanger 2, the deviation (T / M oil temperature−) between the current lubricating oil temperature (T / M oil temperature) in the transmission and its target value (target oil temperature). Target oil temperature) is calculated. Next, a ratio (deviation / target control time) between the deviation and the target control time is calculated. This target control time is a target time for setting the deviation to zero. Next, the product of this ratio and a predetermined gain (deviation / target control time × gain) is calculated. This gain is appropriately changed based on, for example, the T / M oil temperature or a predetermined expected oil temperature. Next, the product (deviation / target control time × gain × (T / M heat capacity)) of this product and the heat capacity (T / M heat capacity) of the transmission is calculated, and this product is used as the required heat dissipation amount. The T / M heat capacity is calculated by the following formula (1).

T / M heat capacity = (lubricating oil volume × specific gravity × specific heat + iron mass × specific heat + aluminum mass × specific heat) × 4.186605 (1)

  Next, the target flow rate of the lubricating oil in the heat exchanger 2 is calculated based on the necessary heat release amount, the vehicle speed (wind speed), the outside air temperature, and the heat exchanger inlet oil temperature. Next, based on this target flow rate and the line pressure solenoid command current, a target current (flow control solenoid target current) of the flow control valve 31 of the flow control unit 3 is calculated. The flow rate control valve 31 is driven based on this target current, and the flow rate of the lubrication amount in the heat exchanger 2 is controlled. Thereby, the oil temperature of the lubricating oil in the transmission is properly maintained.

[Modification 2]
Further, in the oil temperature control device 1, an expected oil temperature after a predetermined time is calculated based on the difference between the current heat generation amount in the transmission and the heat dissipation amount of the heat exchanger 2, and the expected oil temperature and the target oil temperature are calculated. The required heat radiation amount in the heat exchanger 2 may be calculated based on the deviation from (see FIGS. 4 and 5). Then, the flow rate control unit 3 is driven based on the necessary heat radiation amount, and the flow rate of the lubrication amount in the heat exchanger 2 is controlled. Specifically, the following feedback control can be performed.

  First, an expected value (expected oil temperature) of the oil temperature of the transmission after a predetermined time is calculated (see FIG. 4). In the calculation of the predicted oil temperature, first, the current lubricating oil in the heat exchanger 2 is based on the command current (flow control solenoid command current) of the flow control valve 31 of the flow control unit 3 and the command current of the line pressure solenoid. Is calculated (see the lower left part of FIG. 4). This current flow rate is calculated based on a predetermined flow rate characteristic map. Then, based on the current flow rate, the vehicle speed (wind speed), the outside air temperature, and the heat exchanger inlet oil temperature, the heat release amount of the heat exchanger 2 is calculated. This amount of heat release is calculated based on a predetermined map indicating the performance characteristics of the heat exchanger 2. Next, the heat dissipation amount of the heat exchanger 2, the heat generation amount due to torque converter loss (T / C loss), the heat generation amount due to transmission loss (T / M loss), and the heat dissipation amount due to surface heat dissipation of the transmission (T / M release) The sum of the amount of heat) and the amount of heat due to heat transfer from the engine is calculated. Next, the product of this sum and the reciprocal of the heat capacity of the transmission (1 / (T / M heat capacity)) is calculated. Next, the product of this product and the target control time is calculated. The sum of this product and the T / M oil temperature is calculated and used as the predicted oil temperature.

  Next, a deviation between the predicted oil temperature and the target value (target oil temperature) of the transmission oil temperature is calculated (see FIG. 5). Next, a ratio (deviation / target control time) between the deviation and the target control time is calculated. Next, the product of this ratio and a predetermined gain (deviation / target control time × gain) is calculated. Next, the product (deviation / target control time × gain × (T / M heat capacity)) of this product and the heat capacity (T / M heat capacity) of the transmission is calculated, and this product is the required heat dissipation (FB required heat dissipation). Used as

  Next, the target flow rate of the lubricating oil in the heat exchanger 2 is calculated based on the necessary heat release amount, the vehicle speed (wind speed), the outside air temperature, and the heat exchanger inlet oil temperature. Next, based on this target flow rate and the line pressure solenoid command current, a target current (flow control solenoid target current) of the flow control valve 31 of the flow control unit 3 is calculated. The flow rate control valve 31 is driven based on this target current, and the flow rate of the lubrication amount in the heat exchanger 2 is controlled. Thereby, the oil temperature of the lubricating oil in the transmission is properly maintained.

  In this embodiment, in the predicted oil temperature calculation step (see FIG. 4), the output value of the oil temperature sensor (heat exchanger inlet oil temperature sensor) at the inlet of the heat exchanger 2 is used to perform heat exchange. The heat radiation amount of the container 2 is calculated. However, the present invention is not limited to this, and the amount of heat released from the heat exchanger 2 may be calculated using a value obtained from the current oil temperature (T / M oil temperature) of the transmission. In such a configuration, by adjusting the T / M oil temperature, the time delay of the oil temperature change from the T / M oil temperature measurement position (installation position of the T / M oil temperature sensor) to the inlet portion of the heat exchanger 2 is achieved. Is alleviated. Thereby, there exists an advantage which the precision of the oil temperature control of a transmission improves. Moreover, since the heat dissipation amount of the heat exchanger 2 can be calculated using the output value of the T / M oil temperature sensor, the heat exchanger inlet oil temperature sensor can be omitted. Thereby, there is an advantage that the product cost can be reduced.

[Modification 3]
Further, in the oil temperature control device 1, the FF required heat release amount (feedforward control amount) calculated based on the heat amount balance in the configuration shown in FIG. 2 and the speed change in the configuration (modification 1) shown in FIG. The sum of the FB required heat release amount (feedback control amount) calculated based on the deviation between the T / M oil temperature of the machine and the target oil temperature may be used as the required heat release amount of the heat exchanger 2 (FIG. 6). reference). Then, the flow rate control unit 3 is driven based on the necessary heat radiation amount, and the flow rate of the lubrication amount in the heat exchanger 2 is controlled. Specifically, the following feedback control can be performed.

  First, in calculating the FB required heat dissipation amount, a deviation between the T / M oil temperature of the transmission and the target oil temperature is calculated. Next, a ratio (deviation / target control time) between the deviation and the target control time is calculated. Next, the product of this ratio and a predetermined gain (deviation / target control time × gain) is calculated. Next, a product (deviation / target control time × gain × (T / M heat capacity)) of this product and the heat capacity (T / M heat capacity) of the transmission is calculated, and this product is used as the FB required heat dissipation amount.

  Next, the sum of the FB required heat dissipation amount and the FF required heat dissipation amount calculated based on the heat balance in the configuration shown in FIG. 2 is calculated as the required heat dissipation amount of the heat exchanger 2.

  Next, the target flow rate of the lubricating oil in the heat exchanger 2 is calculated based on the necessary heat release amount, the vehicle speed (wind speed), the outside air temperature, and the heat exchanger inlet oil temperature. Next, based on this target flow rate and the line pressure solenoid command current, a target current (flow control solenoid target current) of the flow control valve 31 of the flow control unit 3 is calculated. The flow rate control valve 31 is driven based on this target current, and the flow rate of the lubrication amount in the heat exchanger 2 is controlled. Thereby, the oil temperature of the lubricating oil in the transmission is properly maintained. Further, since the sum of the feedforward control amount (FF required heat dissipation amount in FIG. 2) and the feedback control amount (FB required heat dissipation amount in FIG. 3) is used as the required heat dissipation amount of the heat exchanger 2, the oil temperature of the transmission There is an advantage that can be quickly converged to the target oil temperature.

[Modification 4]
Moreover, in this oil temperature control apparatus 1, FF required heat dissipation amount (feedforward control amount) calculated based on the heat balance in the configuration shown in FIG. 2, and the configuration shown in FIGS. 4 and 5 (Modification 2) The sum of the FB required heat dissipation amount (feedback control amount) calculated based on the deviation between the expected oil temperature of the transmission and the target oil temperature may be used as the required heat dissipation amount of the heat exchanger 2 (FIG. 7). And the flow control part 3 is driven based on this required heat radiation amount, and the flow volume of the lubricating oil in the heat exchanger 2 is controlled. Specifically, the following feedback control can be performed.

  First, in calculating the FB required heat dissipation amount, a deviation between the expected oil temperature of the transmission and the target oil temperature is calculated. Next, a ratio (deviation / target control time) between the deviation and the target control time is calculated. Next, the product of this ratio and a predetermined gain (deviation / target control time × gain) is calculated. Next, a product (deviation / target control time × gain × (T / M heat capacity)) of this product and the heat capacity (T / M heat capacity) of the transmission is calculated, and this product is used as the FB required heat dissipation amount.

  Next, the sum of the FB required heat dissipation amount and the FF required heat dissipation amount calculated based on the heat balance in the configuration shown in FIG. 2 is calculated as the required heat dissipation amount of the heat exchanger 2.

  Next, the target flow rate of the lubricating oil in the heat exchanger 2 is calculated based on the necessary heat release amount, the vehicle speed (wind speed), the outside air temperature, and the heat exchanger inlet oil temperature. Next, based on this target flow rate and the line pressure solenoid command current, a target current (flow control solenoid target current) of the flow control valve 31 of the flow control unit 3 is calculated. The flow rate control valve 31 is driven based on this target current, and the flow rate of the lubrication amount in the heat exchanger 2 is controlled. Thereby, the oil temperature of the lubricating oil in the transmission is properly maintained. Further, since the sum of the feedforward control amount (FF required heat release amount in FIG. 2) and the feedback control amount (FB required heat release amount in FIG. 5) is used as the required heat release amount of the heat exchanger 2, the oil temperature of the transmission There is an advantage that can be quickly converged to the target oil temperature.

  As described above, the oil temperature control device for a transmission according to the present invention is useful in that it can appropriately control the oil temperature of the transmission.

DESCRIPTION OF SYMBOLS 1 Oil temperature control apparatus 2 Heat exchanger 3 Flow control part 31 Flow control valve 11 Secondary regulator valve 12-14 Lubrication system 151,152 Lubricating oil path

Claims (2)

An oil temperature control device for a transmission that controls the oil temperature of the transmission by performing heat exchange of lubricating oil of the transmission with a heat exchanger,
A speed change control unit comprising a flow rate control unit that controls a flow rate of lubricating oil supplied to the heat exchanger, and the flow rate control unit controls the flow rate of the lubricating oil based on a heat generation amount due to transmission loss. Machine oil temperature control device.   2. The oil temperature control device for a transmission according to claim 1, wherein a value obtained by converting a current oil temperature of the transmission is used as the oil temperature of the lubricating oil used for calculating the heat radiation amount of the heat exchanger.

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