JP7041563B2 - Hydraulic control device - Google Patents

Description

The present invention relates to a hydraulic control device.

In a continuously variable transmission (CVT), a chain belt is wound around a primary pulley and a secondary pulley, and the rotation of the primary pulley is transmitted to the secondary pulley by the chain belt. In continuously variable transmissions, slippage may occur between the chain belt and the primary or secondary pulley. For example, in Patent Document 1, slippage between the chain belt and the secondary pulley is caused by comparing the target secondary pressure of the oil supplied to the secondary pulley with the actual secondary pressure and performing feedback control to the target secondary pressure. Techniques for prevention are disclosed.

Japanese Unexamined Patent Publication No. 2014-105665

For example, if the volume of oil accommodated on the secondary pulley side is larger than the volume of oil accommodated on the primary pulley side, the flow rate of oil supplied to the secondary pulley may be insufficient or excessive when shifting. be. At this time, if the flow rate of the oil supplied to the secondary pulley is insufficient with respect to the volume change of the oil accommodated on the secondary pulley side at the time of shifting, slip may occur between the belt and the secondary pulley. Further, if the flow rate of the oil supplied to the secondary pulley becomes excessive with respect to the volume change when the oil accommodated on the secondary pulley side is changed, a shift delay may occur.

Therefore, an object of the present invention is to provide a hydraulic control device capable of suppressing an insufficient or excessive flow rate of oil supplied to a secondary pulley.

In order to solve the above problems, the hydraulic control device of the present invention supplies the solenoid valve that regulates the output hydraulic pressure according to the current value of the applied current, and the secondary pulley of the stepless transmission based on the output hydraulic current. A secondary pressure control valve that regulates the secondary pressure of the oil to be used, and a control unit that determines the current value of the current applied to the solenoid valve and applies the current of the determined current value to the solenoid valve. The control unit derives an offset amount with respect to the determined current value when a predetermined condition in which the flow rate of the oil supplied to the secondary pulley is predicted to be insufficient or excessive is satisfied, and uses the offset amount as the offset amount. Based on this, the current value is corrected, and the current of the corrected current value is applied to the solenoid valve, and the offset amount to be derived differs between the drive running state and the coast running state .
Further, in order to solve the above problems, the hydraulic control device of the present invention has a solenoid valve that regulates the output hydraulic pressure according to the current value of the applied current, and a secondary pulley of the stepless transmission based on the output hydraulic pressure. A secondary pressure control valve that regulates the secondary pressure of the oil supplied to the solenoid valve, and a control unit that determines the current value of the current applied to the solenoid valve and applies the current of the determined current value to the solenoid valve. , The control unit derives an offset amount with respect to the determined current value when a predetermined condition for which it is predicted that the flow rate of the oil supplied to the secondary pulley is insufficient or excessive is satisfied, and the offset The current value is corrected based on the amount, and the current of the corrected current value is applied to the solenoid valve. The offset amount is a first offset amount in which a positive value is determined and a positive value or a negative value. It is derived by adding with the specified second offset amount.

Further, the control unit may make the offset amount to be derived different between the drive running state and the coast running state.

Further, the first offset amount may be determined based on the target secondary pressure after pressure adjustment and the current temperature of the oil.

Further, the second offset amount is determined by the required flow rate of the oil derived at least based on the difference between the current position and the target position in the primary pulley of the continuously variable transmission and the current temperature of the oil. It may be decided based on.

Further, it is preferable that the control unit can derive the first offset amount only when the current temperature of the oil is equal to or lower than a predetermined value.

Further, it is preferable that the control unit can derive the first offset amount only when the gear ratio of the continuously variable transmission is within a predetermined range.

Further, the predetermined range of the gear ratio may be on the OD side of the central gear ratio, which is intermediate between the LOW at which the gear ratio is maximum and the OD at which the gear ratio is minimum.

Further, it is preferable that the control unit can derive the second offset amount only when the current temperature of the oil is equal to or lower than a predetermined value.

Further, when the amount of change in the target position of the primary pulley of the continuously variable transmission per unit time is equal to or more than a predetermined value, or the position of the target position in the primary pulley per unit time, the control unit may be used. It is preferable that the second offset amount can be derived only when the amount of change is not more than a predetermined value.

Further, it is preferable that the control unit can derive the second offset amount only when the difference between the current position and the target position in the primary pulley of the continuously variable transmission exceeds a predetermined range.

According to the present invention, it is possible to prevent the flow rate of oil supplied to the secondary pulley from becoming insufficient or excessive.

It is a figure explaining the structure of a vehicle. It is a figure which shows the structure of the power transmission mechanism. It is a figure explaining the structure of the hydraulic pressure control device. It is a flowchart explaining the flow of the correction control process of the current value by TCU. It is a figure which shows an example of the characteristic map which is referred when calculating a target primary rotation speed. It is a figure which shows an example of the characteristic map which is referred to when calculating the required secondary pressure per unit torque. It is a figure which shows the 1st offset amount map. It is a figure which shows an example of the characteristic map which is referred when calculating the required flow rate. It is a figure which shows the 2nd offset amount map.

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The dimensions, materials, other specific numerical values, etc. shown in the embodiment are merely examples for facilitating the understanding of the invention, and do not limit the present invention unless otherwise specified. In the present specification and the drawings, elements having substantially the same function and configuration are designated by the same reference numerals to omit duplicate description, and elements not directly related to the present invention are not shown. do.

FIG. 1 is a diagram illustrating a configuration of a vehicle 100. In FIG. 1, the control flow is indicated by a broken line arrow, and the oil flow is indicated by a solid line arrow. As shown in FIG. 1, the vehicle 100 includes an engine 202, a power transmission mechanism 200, an ECU (Engine Control Unit) 300, a hydraulic control device 400, and the like. The engine 202 is, for example, a gasoline engine. As will be described in detail later, the power transmission mechanism 200 shifts the power of the engine 202 and transmits it to the wheels. The ECU 300 is composed of a microcomputer including a central processing unit (CPU), a ROM in which a program or the like is stored, a RAM as a work area, and the like, and controls the entire engine 202 in an integrated manner. The hydraulic control device 400 supplies oil to the continuously variable transmission (CVT) 210 or the like constituting the power transmission mechanism 200.

Hereinafter, first, a schematic configuration of the power transmission mechanism 200 will be described, and then the hydraulic control device 400 will be described in detail.

FIG. 2 is a diagram showing the configuration of the power transmission mechanism 200. As shown in FIG. 2, the engine 202 includes a crankshaft 202a, and the piston is reciprocated by the explosive pressure in the combustion chamber to rotate the crankshaft 202a. A continuously variable transmission 210 is connected to the crankshaft 202a of the engine 202 from the engine 202 side via a torque converter 206 and an input clutch 208.

The torque converter 206 includes a front cover 206a connected to the crankshaft 202a and a pump impeller 206b fixed to the front cover 206a. Further, in the torque converter 206, the turbine runner 206c is arranged to face the pump impeller 206b in the front cover 206a, and the turbine shaft 206d is connected to the turbine runner 206c. Further, in the torque converter 206, the stator 206e is arranged on the inner peripheral side between the pump impeller 206b and the turbine runner 206c, and the working fluid is sealed inside.

The torque converter 206 rotates the turbine runner 206c by sending the working fluid to the outer peripheral side by rotating the pump impeller 206b and sending the working fluid to the turbine runner 206c. As a result, power is transmitted from the crankshaft 202a to the turbine runner 206c.

The stator 206e changes the flow direction of the working fluid sent out from the turbine runner 206c and returns it to the pump impeller 206b to promote the rotation of the pump impeller 206b. Therefore, the torque converter 206 can amplify the transmission torque.

Further, in the torque converter 206, a clutch plate 206f that rotates integrally with the turbine shaft 206d is arranged to face the inner surface of the front cover 206a. The clutch plate 206f is hydraulically pressed against the front cover 206a, so that power is transmitted from the crankshaft 202a to the turbine shaft 206d. Further, by controlling the hydraulic pressure, the clutch plate 206f slides into contact with the front cover 206a, so that the power transmitted from the crankshaft 202a to the turbine shaft 206d can be adjusted.

The input clutch 208 has a fixed case 208a fixed to the turbine shaft 206d and a moving member 208b that rotates integrally with the rotating shaft 204a so as to face each other. The 208b moves towards the fixed case 208a.

The input clutch 208 cuts off the transmission of power between the turbine shaft 206d and the rotating shaft 204a in an open state in which the fixed case 208a and the moving member 208b are separated from each other. Further, the input clutch 208 transmits power between the turbine shaft 206d and the rotary shaft 204a in a connected state in which the moving member 208b is pressed against the fixed case 208a by the hydraulic pressure applied to the input clutch 208. The input clutch 208 can adjust the power transmitted between the turbine shaft 206d and the rotary shaft 204a by the applied hydraulic pressure.

The continuously variable transmission 210 includes a primary pulley 212, a secondary pulley 214, and a belt 216. The primary pulley 212 is provided on the rotation shaft 204a, and the secondary pulley 214 is provided on the parallel shaft 218 arranged parallel to the rotation shaft 204a. The belt 216 is composed of a chain belt in which link plates are connected by pins. The belt 216 is stretched between the primary pulley 212 and the secondary pulley 214, and transmits power between the primary pulley 212 and the secondary pulley 214. Here, the case where the belt 216 is composed of a chain belt has been described, but the belt 216 may be composed of, for example, a metal belt having a plurality of pieces (elements) sandwiched between two rings.

The primary pulley 212 includes a movable sheave 212a that can move in the rotation axis direction and a fixed sheave 212b that is restricted from moving in the rotation axis direction. The movable sheave 212a and the fixed sheave 212b are provided so as to face each other in the axial direction of the rotation shaft 204a. Further, the facing surfaces of both the movable sheave 212a and the fixed sheave 212b are cone surfaces 212c having a substantially conical shape, and the cone surface 212c forms a groove in which the belt 216 is stretched.

Similarly, the secondary pulley 214 is composed of a fixed sheave 214a whose movement in the rotation axis direction is restricted and a movable sheave 214b which can move in the rotation axis direction. The fixed sheave 214a and the movable sheave 214b are provided so as to face each other in the axial direction of the parallel axis 218. Further, the facing surfaces of both the fixed sheave 214a and the movable sheave 214b are cone surfaces 214c having a substantially conical shape, and the cone surface 214c forms a groove in which the belt 216 is stretched.

The position of the movable sheave 212a of the primary pulley 212 in the axial direction of the rotary shaft 204a is changed by the hydraulic pressure of the oil supplied from the hydraulic pressure control device 400. Further, the position of the movable sheave 214b of the secondary pulley 214 in the axial direction of the parallel shaft 218 is changed by the hydraulic pressure of the oil supplied from the hydraulic pressure control device 400.

In this way, the facing distances between the movable sheave 212a and the fixed sheave 212b of the primary pulley 212 and the fixed sheave 214a and the movable sheave 214b of the secondary pulley 214 are variable. The groove in which the belt 216 is stretched is narrow in the radial direction of the movable sheave 212a and the fixed sheave 212b of the primary pulley 212 and the fixed sheave 214a and the movable sheave 214b of the secondary pulley 214, and is radially outward. It's getting wider. Therefore, when the facing distance between the cone surfaces 212c and 214c changes and the groove width in which the belt 216 is stretched is changed, the position where the belt 216 is stretched changes.

Taking the primary pulley 212 as an example, when the facing distance between the cone surfaces 212c becomes wide and the width of the groove over which the belt 216 is laid becomes wide, the position where the belt 216 is stretched on the cone surface 212c becomes the inner diameter side. , The winding diameter of the belt 216 becomes smaller. On the other hand, when the facing distance between the cone surfaces 212c becomes narrow and the width of the groove over which the belt 216 is laid becomes narrow, the position where the belt 216 is stretched is on the outer diameter side of the cone surface 212c, and the winding diameter becomes large. .. In this way, the continuously variable transmission 210 continuously changes the transmission power between the rotating shaft 204a and the parallel shaft 218.

The parallel shaft 218 is connected to the output shaft 222 to which the wheels 226 are connected via the gear mechanism 220a, and the transmission power shifted by the continuously variable transmission 210 is transmitted via the gear mechanism 220a and the output shaft 222. It is transmitted to the wheel 226.

FIG. 3 is a diagram illustrating the configuration of the hydraulic control device 400. In FIG. 3, the oil flow is indicated by a solid arrow and the control flow is indicated by a broken line arrow. As shown in FIG. 3, the hydraulic control device 400 is a duty valve 412 composed of an oil pump 402, a pressure regulating valve 404, a solenoid valve 406, a secondary pressure control valve 408, a TCU (control unit) 410, an up valve and a down valve. , Includes a primary pressure control valve 414.

The oil pump 402 is a pump that operates with the rotation of the engine 202. The oil pump 402 is connected to, for example, the turbine shaft 206d (see FIG. 2) and operates in proportion to the rotation of the turbine shaft 206d. The oil pump 402 sucks oil from an oil pan (not shown), and the sucked oil is passed through the hydraulic control device 400 to the torque converter 206 (see FIG. 2), the primary pulley 212 of the continuously variable transmission 210, and the secondary pulley. It supplies 214, the input clutch 208 and various lubrications. Further, the oil used in the torque converter 206, the primary pulley 212, the secondary pulley 214, the input clutch 208 and the various lubricating portions is returned to an oil pan (not shown) and circulated.

The pressure regulating valve 404 decompresses the line pressure oil supplied from the oil pump 402 to a predetermined pressure and supplies the oil to the solenoid valve 406.

The solenoid valve 406 regulates the oil supplied from the pressure regulating valve 404 and supplies it to the secondary pressure control valve 408 according to the current value of the applied current. In the following, the pressure of the oil regulated by the solenoid valve 406 is referred to as a secondary pressure control signal pressure. Specifically, when the current value of the current applied to the solenoid valve 406 increases, the output secondary pressure control signal pressure drops, and when the current value of the current applied to the solenoid valve 406 decreases, the output secondary pressure The control signal pressure increases. The current value of the current applied to the solenoid valve 406 is controlled by the TCU (Transmission Control Unit) 410.

The secondary pressure control valve 408 adjusts the line pressure oil supplied from the oil pump 402 based on the secondary pressure control signal pressure output from the solenoid valve 406 to the input clutch 208, the movable sheave 212a, and the movable sheave 214b. Supply. In the following, the pressure of the oil regulated by the secondary pressure control valve 408 will be referred to as a secondary pressure. Specifically, the spool valve shaft (not shown) in the secondary pressure control valve 408 is moved in the secondary pressure control valve 408 by the secondary pressure control signal pressure of the oil supplied from the solenoid valve 406. As a result, the oil at the line pressure supplied from the oil pump 402 can be reduced to a desired secondary pressure. That is, the oil supplied from the solenoid valve 406 is used to regulate the secondary pressure, and is not supplied to the movable sheave 212a of the primary pulley 212, the movable sheave 214b of the secondary pulley 214, and the input clutch 208.

The duty valve 412 includes an up valve and a down valve, and regulates the oil of the line pressure supplied from the oil pump 402 and supplies it to the primary pressure control valve 414. In the following, the pressure of the oil regulated by the duty valve 412 is referred to as a primary pressure control signal pressure. Here, the up valve is used to increase the primary pressure control signal pressure, and the down valve is used to decrease the primary pressure control signal pressure. Further, the control of the up valve and the down valve in the duty valve 412 is performed by the TCU 410.

The primary pressure control valve 414 adjusts the line pressure oil supplied from the oil pump 402 based on the primary pressure control signal pressure output from the duty valve 412 and supplies the oil to the movable sheave 212a. In the following, the pressure of the oil regulated by the primary pressure control valve 414 is referred to as a primary pressure. Specifically, the spool valve shaft (not shown) in the primary pressure control valve 414 is moved in the primary pressure control valve 414 by the primary pressure control signal pressure of the oil supplied from the duty valve 412. As a result, the oil at the line pressure supplied from the oil pump 402 can be reduced to a desired primary pressure. That is, the oil supplied from the duty valve 412 is used to regulate the primary pressure and is not supplied to the movable sheave 212a of the primary pulley 212.

The TCU 410 is a microcomputer including a CPU, RAM, and ROM, and controls the current value of the current applied to the solenoid valve 406 and the duty valve 412. As will be described in detail later, the TCU 410 determines the target secondary pressure control signal pressure so that the secondary pressure control valve 408 outputs the oil of the target secondary pressure that is the target of the hydraulic pressure supplied to the secondary pulley 214, and this determination is made. Apply the current value of the current corresponding to the target secondary pressure to the solenoid.

As described above, both the primary pressure oil and the secondary pressure oil will be supplied to the movable sheave 212a of the primary pulley 212. Therefore, the influence of the secondary pressure on the slip between the primary pulley 212 and the belt 216 is relatively small. Further, each of the up valve and the down valve has a hysteresis characteristic in which the output hydraulic pressure (primary pressure control signal pressure) differs with respect to the current value in the increasing direction and the decreasing direction of the current value. However, as described above, since the up valve boosts the primary pressure control signal pressure and the down valve lowers the primary pressure control signal pressure, the up valve and the down valve have a hysteresis characteristic of the primary pulley 212. The effect on slippage with the belt 216 is relatively small.

On the other hand, as described above, only the oil of the secondary pressure is applied to the movable sheave 214b of the secondary pulley 214. Therefore, the influence of the secondary pressure on the slip between the secondary pulley 214 and the belt 216 is large. If a response delay occurs in the adjustment of the secondary pressure, slippage may occur between the secondary pulley 214 and the belt 216. Similarly, since only the secondary pressure is applied to the input clutch 208, the influence of the secondary pressure on the slip of the input clutch 208 is large.

Subsequently, a specific flow of the current value correction control process by the TCU 410 will be described with reference to FIG. FIG. 4 is a flowchart illustrating the flow of the current value correction control process by the TCU 410. The current value correction control process by the TCU 410 is executed, for example, as an interrupt process at a predetermined time interval.

First, the TCU 410 derives the uncorrected current value (step S100). Here, the pre-correction current value is a current value that does not take into consideration the correction amount when determining the current value applied to the solenoid valve 406. The derivation of the uncorrected current value will be described in detail below.

First, the TCU 410 derives a target primary rotation speed based on the vehicle speed and the accelerator opening degree. FIG. 5 is a diagram showing an example of a characteristic map referred to when calculating the target primary rotation speed. In the characteristic map shown in FIG. 5, the accelerator opening that increases or decreases with the amount of depression of the accelerator pedal between the characteristic line LOW that maximizes the gear ratio and the characteristic line OD that minimizes the gear ratio (10 in FIG. 5). A plurality of characteristic lines corresponding to% to 30%) are set. The TCU 410 can derive the target rotation speed (target primary rotation speed) of the primary pulley 212 by referring to this characteristic map based on the vehicle speed and the accelerator opening degree.

The TCU 410 derives a target gear ratio based on the target primary rotation speed and the actual secondary rotation speed. Specifically, the target gear ratio is based on the target primary rotation speed derived in step S100 and the value of the rotation speed of the secondary pulley 214 (actual secondary rotation speed) detected by the secondary rotation speed sensor (not shown). (Actual secondary rotation speed / target primary rotation speed) is derived.

The TCU 410 derives the required hydraulic pressure per unit torque based on the target gear ratio and the input torque. For the input torque, the larger value of the actual torque and the target torque acquired from the ECU 300 is used. FIG. 6 is a diagram showing an example of a characteristic map referred to when calculating the required secondary pressure per unit torque. In the characteristic map shown in FIG. 6, a plurality of characteristic lines corresponding to the input torque are set, and the required hydraulic pressure per unit torque is derived by referring to this characteristic map based on the input torque and the target gear ratio. You can do it.

The TCU 410 multiplies the required hydraulic pressure per unit torque by the target gear ratio to derive the target secondary pressure of the hydraulic pressure supplied to the secondary pulley 214. The TCU 410 obtains the target secondary pressure control signal pressure from the target secondary pressure and derives the pre-correction current value. Specifically, a map showing the correspondence between the target secondary pressure and the target secondary pressure control signal pressure is stored in advance, and the target secondary pressure control signal pressure is derived by using this map. Further, in order to adjust the pressure from the current hydraulic pressure to the target secondary pressure control signal pressure, a map for deriving a current value (pre-correction current value) increased or decreased from the current current value is stored in advance. Then, the pre-correction current value is derived by using the map related to the pre-correction current value.

Subsequently, the TCU 410 determines whether or not the first offset setting condition is satisfied (step S102). As a result, when it is determined that the first offset setting condition is satisfied (YES in step S102), the process is transferred to step S104 described later, and when it is determined that the first offset setting condition is not satisfied (step S102). NO), the process is transferred to step S106 described later.

Here, as the first offset setting condition, the first offset setting condition (1) the oil temperature is equal to or less than a predetermined value, and the first offset setting condition (2) the gear ratio is within a predetermined range. It is assumed that both conditions are satisfied.

In general, the viscosity of oil changes depending on the temperature. When the temperature of oil is high, the viscosity is low, and when the temperature of oil is low, the viscosity is high. The first offset setting condition (1) is mainly provided in consideration of the influence of the temperature change on the viscosity of the oil. In the present embodiment, for the first offset setting condition (1), a predetermined value of the oil temperature is set in the entire range. However, regarding the first offset setting condition (1), the predetermined value of the oil temperature may be set to a desired value without setting the predetermined value of the oil temperature over the entire area.

Further, in the present embodiment, regarding the first offset setting condition (2), the vicinity of the OD between the LOW where the gear ratio is the maximum and the OD where the gear ratio is the minimum is set as a predetermined range of the gear ratio. .. That is, the OD side of the central gear ratio, which is between LOW and OD, is set as a predetermined range of the gear ratio. This is a sufficient target to suppress slippage between the secondary pulley 214 and the belt 216 because the required pressure in the input clutch 208 is larger than the required pressure in the secondary pulley 214 when the gear ratio is near the OD. This is because even if the secondary pressure is set, the target secondary pressure tends to be less than the required pressure in the input clutch 208. As described above, the first offset setting condition (2) is provided in consideration of suppressing slippage in the input clutch 208.

When the TCU 410 determines in step S102 that the first offset setting condition is satisfied, the TCU 410 determines the first offset amount (step S104). Specifically, the first offset amount is determined based on the target secondary pressure and the oil temperature with reference to the preset first offset amount map. FIG. 7 is a diagram showing a first offset amount map. As shown in FIG. 7, in the first offset amount map, at the same target secondary pressure, the lower the oil temperature, the larger the first offset amount. Further, in the first offset amount map, the lower the target secondary pressure is, the larger the first offset amount is at the same oil temperature. In other words, at the same target secondary pressure, the higher the oil temperature, the smaller the first offset amount, and at the same oil temperature, the higher the target secondary pressure, the smaller the first offset amount. Therefore, when the oil temperature is the lowest value and the target secondary pressure is the lowest value in the first offset amount map, the first offset amount is the largest value. Further, when the oil temperature is the largest value and the target secondary pressure is the highest value, the first offset amount is the smallest value.

Here, in the region where the input torque is relatively small, the required pressure in the input clutch 208 is larger than the required pressure in the secondary pulley 214. On the contrary, in the region where the input torque is relatively large, the required pressure in the input clutch 208 is smaller than the required pressure in the secondary pulley 214. Therefore, the offset amount in the region where the target secondary pressure is relatively high is mainly effective in suppressing the slip of the input clutch 208. On the other hand, the offset amount in the region where the target secondary pressure is relatively low is mainly effective in suppressing the slip between the secondary pulley 214 and the belt 216.

Further, in the present embodiment, the first offset amount map is a first offset amount map for the drive driving state mainly referred to in the driving driving state and a first offset for the coast driving state mainly referred to in the coast driving state. It has a quantity map. The first offset amount map for the driving driving state is set to have a smaller offset amount than the first offset amount map for the coast driving state in consideration of the influence of fuel consumption during the driving driving. Since the fuel is originally cut in the coastal running state, the influence on fuel consumption can be reduced even if the offset amount is set large.

As described above, there is a difference in the offset amount between the first offset amount map for the drive running state and the first offset amount map for the coast running state. In the present embodiment, the timing of switching the first offset amount map to be referred to is different depending on whether the transition from the coast running state to the driving running state or the transition from the driving running state to the coast running state. Specifically, in the case of transition from the drive running state to the coast running state, the first offset amount map for the driving running state is immediately switched to the first offset amount map for the coast running state. On the other hand, when the transition from the coast running state to the driving running state is performed, a delay is provided when switching from the first offset amount map for the coast running state to the first offset amount map for the driving running state. .. That is, by preventing the switching from the first offset amount map for the coast running state with a large offset amount to the first offset amount map for the drive running state with a small offset amount during the boosting of the secondary pressure. , It is possible to shift gears smoothly.

Next, the TCU 410 determines whether the first offset release condition is satisfied (step S106). As a result, when it is determined that the first offset release condition is satisfied (YES in step S106), the process is transferred to step S108 described later, and when it is determined that the first offset release condition is not satisfied (step S106). NO), the process is transferred to step S110 described later.

Here, as the first offset release condition, the above-mentioned first offset setting condition (1) the oil temperature is equal to or less than a predetermined value, and the first offset setting condition (2) the gear ratio is within a predetermined range. It is assumed that one of the conditions of 2 is not satisfied.

When the TCU 410 determines in step S106 that the first offset release condition is satisfied, the TCU 410 releases the first offset amount (step S108). If the first offset amount is not set, the process moves to step S110.

The TCU 410 determines whether the second offset setting condition is satisfied (step S110). As a result, when it is determined that the second offset setting condition is satisfied (YES in step S110), the process is transferred to step S112 described later, and when it is determined that the second offset setting condition is not satisfied (step S110). NO), the process is transferred to step S114 described later.

Here, as the second offset setting condition, the second offset setting condition (1) the temperature of the oil is equal to or less than a predetermined value, and the second offset setting condition (2) the target primary pulley position change amount per unit time is predetermined. It is equal to or more than the value, or the amount of change in the target primary pulley position per unit time is less than or equal to the predetermined value, and (3) the deviation of the primary pulley position, which is the difference between the target primary pulley position and the actual primary pulley position, is within the predetermined range. It is assumed that all three conditions of exceeding the above are satisfied.

In general, the viscosity of oil changes depending on the temperature. When the temperature of oil is high, the viscosity is low, and when the temperature of oil is low, the viscosity is high. The second offset setting condition (1) is mainly provided in consideration of the influence of the temperature change on the viscosity of the oil. In the present embodiment, for the second offset setting condition (1), a predetermined value of the oil temperature is set in the entire range. However, regarding the second offset setting condition (1), the predetermined value of the oil temperature may be set to a desired value without setting the predetermined value of the oil temperature over the entire area.

Further, in the above-mentioned second offset setting condition (2), the target primary pulley position change amount per unit time is equal to or more than a predetermined value when the shift speed in the upshift where the gear ratio is low is relatively fast. It corresponds. Further, the fact that the target primary pulley position change amount per unit time is not more than a predetermined value corresponds to the case where the shift speed in the downshift where the gear ratio is high is relatively fast. When the shift speed in the upshift is relatively fast, or when the shift speed in the downshift is relatively fast, the volume change of the oil accommodated on the secondary pulley 214 side becomes large, and the flow rate of the oil supplied to the secondary pulley 214 becomes large. This is because it is expected that there will be a shortage or an excess.

Further, in the second offset setting condition (3) described above, the actual primary pulley position is derived by estimation from the current gear ratio in the TCU 410. Further, the case where the primary pulley position deviation exceeds a predetermined range corresponds to the case where the downshift amount or the upshift amount is relatively large. The value of the primary pulley position deviation is based on the position of the movable sheave 212a of the primary pulley 212 in OD (“0”). That is, in the case of an upshift, the primary pulley position deviation takes a negative value, and in the case of a downshift, the primary pulley position deviation takes a positive value.

When the TCU 410 determines in step S110 that the second offset setting condition is satisfied, the TCU 410 determines the second offset amount (step S112). Specifically, first, the required flow rate of the oil to be supplied to the secondary pulley 214 is derived by referring to the preset required flow rate map. FIG. 8 is a diagram showing a required flow rate map. As shown in FIG. 8, in the required flow rate map, in the range where the primary pulley position deviation is positive (downshift), the larger the primary pulley position deviation is, the larger the required flow rate is. On the other hand, in the range where the primary pulley position deviation is negative (upshift), the larger the primary pulley position deviation is, the larger the required flow rate is, and the larger the negative value is. Further, when the value of the primary pulley position deviation is "0", the value of the required flow rate also takes "0". In FIG. 8, the same value is set on the vertical axis regardless of the oil temperature.

That is, since it is predicted that the flow rate of the oil supplied to the secondary pulley will be excessive in the upshift, a required flow rate of a negative value is derived so as to discharge the oil supplied to the secondary pulley. Further, since it is predicted that the flow rate of the oil supplied to the secondary pulley will be insufficient in the downshift, a positive required flow rate is derived so as to increase the oil supplied to the secondary pulley.

Next, the TCU 410 determines the second offset amount based on the required flow rate derived as described above and the oil temperature with reference to the preset second offset amount map. FIG. 9 is a diagram showing a second offset amount map. As shown in FIG. 9, the second offset amount map takes a positive value in which the second offset amount increases as the oil temperature decreases with respect to the same required flow rate in the range where the required flow rate is positive. Further, in the second offset amount map, in the range where the required flow rate is positive, the second offset amount becomes a positive value as the required flow rate becomes larger and the required flow rate becomes larger with respect to the same oil temperature. On the other hand, in the second offset amount map, in the range where the required flow rate is negative, the second offset amount becomes larger as the oil temperature becomes lower with respect to the same required flow rate. Further, in the second offset amount map, in the range where the required flow rate is negative, the larger the required flow rate is, the larger the negative value is, and the larger the second offset amount is. When the required flow rate value is "0", the offset amount value is "0" regardless of the oil temperature.

Next, the TCU 410 determines whether the second offset release condition is satisfied (step S114). As a result, when it is determined that the second offset release condition is satisfied (YES in step S114), the process is transferred to step S116 described later, and when it is determined that the second offset release condition is not satisfied (step S114). NO), the process is transferred to step S118 described later.

Here, the second offset release condition is a case where the state in which the primary pulley position deviation is within a predetermined range is continued for a predetermined time. Here, as the predetermined time, for example, an order of about several seconds is set.

When the TCU 410 determines in step S114 that the second offset release condition is satisfied, the TCU 410 releases the second offset amount (step S116). If the second offset amount is not set, the process moves to step S118.

The TCU 410 adds the first offset amount and the second offset amount to the uncorrected current value derived in step S100 to derive a target current value (step S118).

The TCU 410 applies the target current value derived in step S118 to the solenoid valve 406 (step S120), and ends the correction control process for the current value.

As described above, according to the hydraulic control device 400 of the present embodiment, the TCU 410 supplies the oil to the secondary pulley 214 when the flow rate of the oil to be supplied to the secondary pulley 214 is predicted to be insufficient. Set the offset amount so that becomes large. On the other hand, the TCU 410 sets the offset amount so as to discharge the oil supplied to the secondary pulley 214 when the flow rate of the oil supplied to the secondary pulley 214 is predicted to be excessive. This makes it possible to prevent the flow rate of the oil supplied to the secondary pulley 214 from becoming insufficient or excessive. As a result, it is possible to suppress the possibility that slippage will occur between the belt 216 and the secondary pulley 214, and it is possible to suppress the possibility that a shift delay will occur.

Further, as described above, the first offset amount from which the offset amount is derived mainly when the gear ratio falls within a predetermined range and the position change of the movable sheave 212a of the primary pulley 212 mainly correspond to the position change. By having the offset amount of 2 of the second offset amount from which the offset amount is derived, it is possible to prevent the flow rate of the oil supplied to the secondary pulley 214 from becoming insufficient or excessive.

Although the preferred embodiment of the present invention has been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to such an embodiment. It is clear that a person skilled in the art can come up with various modifications or modifications within the scope of the claims, and it is understood that these also naturally belong to the technical scope of the present invention. Will be done.

In the above embodiment, regarding the value of the required flow rate obtained by referring to the required flow rate map, the required flow rate of the same value is set on the vertical axis of the required flow rate map regardless of the oil temperature. Depending on the temperature, different values of the required flow rate may be set on the vertical axis of the required flow rate map.

Further, in the above embodiment, the solenoid valve 406 is applied with a current having a current value that has been corrected in advance, and feedback control is not particularly performed. However, after the current value correction control process is executed, further feedback is performed. Control may be executed at the same time.

Further, in the above embodiment, the case where the oil of the secondary pressure is also supplied to the input clutch 208 is shown, but the hydraulic pressure of the oil supplied to the input clutch 208 may be controlled by another system. In this case, the first offset amount map and the second offset amount map may be set without considering the input clutch 208.

Further, in the above embodiment, in the second offset setting condition (2), regarding the condition for the case where the shift speed is relatively fast, the case where the target primary pulley position change amount is a predetermined value or more or a predetermined value or less is shown. As the second offset setting condition (2), when the amount of change in the position of the primary pulley 212 per unit time (the amount of change in the actual primary pulley position) is equal to or greater than a predetermined value (when the shift speed in the upshift is relatively fast) or predetermined. The case may be less than or equal to the value (when the shift speed in downshift is relatively fast).

The present invention can be used for hydraulic control devices.

210 Continuously variable transmission 212 Primary pulley 214 Secondary pulley 400 Hydraulic control device 406 Solenoid valve 408 Secondary pressure control valve 410 TCU (control unit)

Claims (11)

A solenoid valve that regulates the output hydraulic pressure according to the current value of the applied current,
A secondary pressure control valve that regulates the secondary pressure of oil supplied to the secondary pulley of the continuously variable transmission based on the output hydraulic pressure.
A control unit that determines the current value of the current applied to the solenoid valve and applies the current of the determined current value to the solenoid valve.
Equipped with
The control unit derives an offset amount with respect to the determined current value when a predetermined condition in which the flow rate of the oil supplied to the secondary pulley is predicted to be insufficient or excessive is satisfied, and the offset amount is obtained. A hydraulic control device that corrects the current value based on the above, applies the corrected current value to the solenoid valve, and makes the derived offset amount different between the drive running state and the coast running state . A solenoid valve that regulates the output hydraulic pressure according to the current value of the applied current,
A secondary pressure control valve that regulates the secondary pressure of oil supplied to the secondary pulley of the continuously variable transmission based on the output hydraulic pressure.
A control unit that determines the current value of the current applied to the solenoid valve and applies the current of the determined current value to the solenoid valve.
Equipped with
The control unit derives an offset amount with respect to the determined current value when a predetermined condition in which the flow rate of the oil supplied to the secondary pulley is predicted to be insufficient or excessive is satisfied, and the offset amount is obtained. The current value is corrected based on the above, and the current of the corrected current value is applied to the solenoid valve.
The offset amount is a hydraulic control device derived by adding a first offset amount in which a positive value is determined and a second offset amount in which a positive value or a negative value is determined . The control unit
The hydraulic control device according to claim 2 , wherein the offset amount to be derived differs between the drive running state and the coast running state. The hydraulic control device according to claim 2 or 3, wherein the first offset amount is determined based on the target secondary pressure after pressure adjustment and the current temperature of the oil. The second offset amount is based on the required flow rate of the oil derived at least based on the difference between the current position and the target position in the primary pulley of the continuously variable transmission and the current temperature of the oil. The hydraulic control device according to any one of claims 2 to 4, which is determined. The control unit
The hydraulic control device according to any one of claims 2 to 5, wherein the first offset amount can be derived only when the current temperature of the oil is equal to or lower than a predetermined value. The control unit
The hydraulic control device according to any one of claims 2 to 6, wherein the first offset amount can be derived only when the gear ratio of the continuously variable transmission is within a predetermined range. The predetermined range of the gear ratio is
The hydraulic control device according to claim 7, wherein the hydraulic control device is on the OD side of the central gear ratio, which is intermediate between the LOW having the maximum gear ratio and the OD having the minimum gear ratio. The control unit
The hydraulic control device according to any one of claims 2 to 8, wherein the second offset amount can be derived only when the current temperature of the oil is equal to or lower than a predetermined value. The control unit
When the amount of change in the target position on the primary pulley of the continuously variable transmission per unit time is greater than or equal to the predetermined value, or when the amount of change in the target position on the primary pulley per unit time is less than or equal to the predetermined value. The hydraulic control device according to any one of claims 2 to 9, wherein the second offset amount can be derived only in a certain case. The control unit
The invention according to any one of claims 2 to 10, wherein the second offset amount can be derived only when the difference between the current position and the target position in the primary pulley of the continuously variable transmission exceeds a predetermined range. Hydraulic control device.

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