JPH05312252A - Hydraulic control system of automatic transmission - Google Patents

Abstract

PURPOSE:To improve a responsive property to speed change and prevent shocks in speed change while improving miniaturization, weight reduction, efficiency and a responsive property to control in line pressure control in a hydraulic control system of an automatic transmission. CONSTITUTION:Line pressure is controlled by the direct electronic control of cam ring eccentric pressure to a variable volume vane pump (c). Also, a line pressure-in-speed-change control means (j) for increasing the cam ring eccentric amount immediately upon inputting a speed change command and a hydraulic speed change control means m for practicing the speed change upon waiting the passage of a predetermined time lag from the speed change command are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic control system for an automatic transmission having a line pressure control device for controlling discharge pressure (line pressure) by direct electronic control of cam ring eccentric pressure to a variable displacement vane pump.

[0002]

2. Description of the Related Art Conventionally, as a hydraulic control system for an automatic transmission having a line pressure control device and a shift hydraulic control device, for example, one disclosed in Japanese Patent Laid-Open No. 62-292948 is known.

As a line pressure control device, there is a variable displacement vane pump which controls the pump discharge amount from low engine speed to high engine speed to a necessary minimum, and the line pressure depends on operating conditions such as throttle opening. A pressure regulator valve that operates with a corresponding pressure modifier pressure as a signal pressure is used to regulate the pressure of pump discharge oil having a flow rate margin by drain control.

In the shift hydraulic control device, the gear position is judged based on the shift schedule set by the detected values from the vehicle speed sensor and the throttle opening sensor, and the detected values of the vehicle speed and the throttle opening are the shift lines of the shift schedule. A device that outputs an operation command to a shift solenoid at the same time as a shift command output when it crosses and switches a shift valve that uses pilot pressure as an operation signal pressure and guides line pressure to a gear position engaging element after speed change and engages it is shown. ing.

[0005]

However, the above-described conventional line pressure control device for the hydraulic control system for an automatic transmission has the following problems.

(1) This system requires a pressure regulator valve, a pressure modifier valve, etc., and has a large number of parts, resulting in an increase in size and weight.

(2) Since a large amount of oil leaks due to the leak from the bleed orifice and the leak from the valve having a large number of valves, the efficiency becomes low.

(3) Since the pressure regulator valve becomes a delay element, the control response of the line pressure deteriorates.

Therefore, as a system for solving the above-mentioned problem, the applicant of the present application has abolished the pressure regulator valve and the pressure modifier valve in Japanese Patent Application No. 3-117777 to replace the cam ring eccentric pressure on the variable displacement vane pump. We proposed a device to control the line pressure by direct electronic control.

However, in this line pressure control device, since it is intended to increase the efficiency with the minimum pump discharge oil amount without draining the hydraulic oil, the clutch piston chamber or the like which eliminates the gap between the plates is provided. During a gear shift in which the pump load flow rate transiently sharply increases due to oil consumption due to the oil supply (pre-charge), if the normal feedback control is continued as it is, the amount of oil is secured and the line pressure is kept constant. The control is delayed, and it takes time to precharge due to the lack of the oil amount, and the shift response is delayed.

Further, in the shift hydraulic pressure control device for controlling the shift hydraulic pressure to the clutch or the like based on the line pressure from the line pressure control device, the clutch pressure is raised by executing the shift at the same time as the shift command, as shown in FIG. As described above, the clutch pressure does not reach a sufficient pressure level at the end of precharge due to the decrease in line pressure, and a surge (fluctuation) occurs due to a sudden load increase due to clutch engagement immediately after the end of precharge, which increases gear shift shock. ..

In the conventional line pressure control device, the pressure regulator valve regulates the pump discharge oil having a flow margin by drain control, and the spool of the pressure regulator valve closes the drain port at the time of gear shifting, and the hydraulic oil drain Since the amount of oil is secured to some extent by reducing the amount, the line pressure drop at the time of gear shifting is not as remarkable as that of the device by the cam ring eccentricity amount control of the variable displacement vane pump.

The present invention has been made by paying attention to the above problems, and in the hydraulic control system of an automatic transmission, while aiming to reduce the size and weight of the line pressure control, improve the efficiency, and improve the control response. The first object is to improve the shift response and prevent shift shock.

The second object is to achieve the first object by setting the delay time according to the oil temperature, the engine speed and the size of the throttle opening.

A third object is to achieve the first or second object while improving the line pressure control accuracy during shifting.

A fourth object is to achieve the third object by setting the increment amount of the cam ring eccentricity amount according to the magnitude of the engine speed.

[0017]

In order to solve the above first problem, in the hydraulic control system for an automatic transmission according to claim 1, the line pressure is controlled by direct electronic control of the cam ring eccentric pressure to the variable displacement vane pump. At the same time, a shift line pressure control means for increasing the cam ring eccentricity immediately when a shift command is input and a shift hydraulic pressure control means for executing a shift after waiting a predetermined delay time from the shift command are provided.

That is, as shown in the claim correspondence diagram of FIG. 1, a variable displacement vane pump c having a cam ring eccentric pressure chamber b for controlling the eccentric amount of the cam ring a according to the magnitude of hydraulic pressure, and the cam ring eccentric pressure chamber b. An eccentric pressure control actuator d for controlling the hydraulic pressure to the external command by an external command,
A fastening pressure control actuator f for controlling the fastening element pressure to the fastening element e on the basis of the line pressure discharged from the variable displacement vane pump c by an external command, and a detection value from the vehicle state detecting means g are set. Gear position determining means i for determining the gear position according to the shift schedule h
When the vehicle state detection value crosses the shift line of the shift schedule h, when a shift command output from the gear position determination means i is input, a control command to increase the cam ring eccentricity is immediately output to the eccentric pressure control actuator d. The shift line pressure control means j, the delay time setting means k for setting a predetermined delay time when a shift command from the gear position determination means i is input, and the elapse of the time set by the delay time setting means k. A shift hydraulic pressure control means m for outputting a shift execution command for waiting the shift and engaging the gear position engagement element to the engagement pressure control actuator f is provided.

In order to solve the above second problem, in the invention according to claim 2, in the hydraulic control system for the automatic transmission according to claim 1, the delay time setting means k is delayed when the oil temperature is equal to or lower than the set temperature. The time is set to zero time, and when the oil temperature exceeds the set temperature, the delay time is set as a function of the engine speed and the throttle opening.

In order to solve the third problem, the invention according to claim 3 estimates the specific discharge amount from the variable displacement vane pump c in the hydraulic control system for an automatic transmission according to claim 1 or 2. Cam ring eccentricity amount detecting means n for controlling the line pressure control means j during shifting.
Is a means for using the detected value of the cam ring eccentricity amount as feedback control information for confirming the increment amount of the cam ring eccentricity amount which is increased at the time of gear shift.

In order to solve the fourth problem, in the invention according to claim 4, in the hydraulic control system for an automatic transmission according to claim 3, the increment amount of the eccentricity of the cam ring which is increased at the time of gear shifting is set to the gear shift command. It is characterized in that a cam ring eccentricity increment setting means p which is set by a function of the engine speed at the time of input is provided.

[0022]

The operation of the present invention will be described.

At the time of gear shifting, the gear position determination means i determines the gear position based on the detected value from the vehicle state detection means g and the set shift schedule h, and the vehicle state detection value crosses the shift line of the shift schedule h. A gear shift command is output when

When the shift line pressure control means j inputs the shift command output from the gear position determination means i, a control command for increasing the cam ring eccentricity is immediately output to the eccentric pressure control actuator d, and the variable displacement vane pump c. The oil discharged from the tank is increased. On the other hand, when the delay time setting means k inputs the shift command output from the gear position determination means i, a predetermined delay time is set, and the shift hydraulic pressure control means m.
In the above, a shift execution command for engaging the post-shift gear position engagement element after the elapse of the time set by the delay time setting means k is output to the engagement pressure control actuator f.

The operation of the invention according to claim 2 will be described.

In setting the delay time, the delay time setting means k sets the delay time to zero time when the oil temperature is below the set temperature, and when the oil temperature exceeds the set temperature, the delay time is set to the engine speed and throttle opening. Set by the degree function.

The operation of the invention according to claim 3 will be described.

The cam ring eccentricity detection value from the cam ring eccentricity detection means n for estimating the specific discharge amount from the variable displacement vane pump c when the control for increasing the cam ring eccentricity is performed in the line pressure control means j during shifting. Is used as feedback control information for confirming the increment of the cam ring eccentricity.

The operation of the invention according to claim 4 will be described.

When performing the control for increasing the cam ring eccentricity amount in the gear shift line pressure control means j, the increment amount of the cam ring eccentricity amount increased in the cam ring eccentricity increment setting means p in the cam ring eccentricity increment amount setting means p when the gear shift command is input. It is set by a function of engine speed.

[0031]

Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) First, the structure will be described.

FIG. 2 is an overall view showing a hydraulic control system for an automatic transmission according to a first embodiment corresponding to the first and second aspects of the invention.

As shown in FIG. 2, the hydraulic control system for the automatic transmission according to the first embodiment has a variable displacement vane pump 1 having a cam ring eccentric pressure chamber 1b for controlling the eccentric amount of the cam ring 1a in accordance with the magnitude of hydraulic pressure. And a three-way duty solenoid valve 2 and a pressure reducing valve 3 (corresponding to an eccentric pressure control actuator) for controlling the hydraulic pressure to the cam ring eccentric pressure chamber 1b by an external command, and a line pressure control device is configured. The clutch 13 (corresponding to a fastening element) based on the line pressure discharged from the variable displacement vane pump 1)
The shift hydraulic pressure control device is configured to include a three-way duty solenoid valve 14 and a pressure reducing valve 15 (corresponding to a fastening pressure control actuator) that controls the clutch pressure to the valve by an external command. Further, the A / T controller 4 for outputting a predetermined duty command to the two-way three-way duty solenoid valves 2 and 14 is provided. It should be noted that although the shift hydraulic control device shows only the configuration for one clutch 13, it has a configuration in which a three-way duty solenoid valve and a pressure reducing valve are provided for each of the fastening elements such as a plurality of clutches and brakes. There is.

The variable capacity vane pump 1 includes a cam ring 1a supported by a pump cover 1c, a rotor 1d and a vane 1e arranged inside the cam ring 1a,
It is configured to have a control piston 1f that is in contact with the cam ring 1a and is supported by a pump cover 1c.

The cam ring 1a has a pin 1 at one end.
The pump cover 1c is swingably supported by g, and a spring 1h for biasing the cam ring 1a in the direction of increasing the eccentric amount of the cam ring 1a is interposed between the pump cover 1c and the pump cover 1c at the other end.

The rotor 1d is provided on a pump input shaft 1i which is connected to an engine output shaft (not shown), and a plurality of rotors 1d are capable of appearing and retracting on the outer periphery of the rotor 1d while slidably contacting the inner peripheral surface 1j of the cam ring 1a. Vane 1e is fitted. The cam ring eccentricity means the eccentricity between the center position of the rotor 1d and the center position of the cam ring 1a.

The control piston 1f is arranged on the outer peripheral portion of the cam ring 1a so as to be in partial contact with the cam ring 1a, and one end of the control piston 1f is provided with the pin 1k.
It is swingably supported by c. A cam ring eccentric pressure chamber 1b is formed between the control piston 1f and the pump cover 1c. When hydraulic pressure is introduced into the cam ring eccentric pressure chamber 1b, a force corresponding to the hydraulic pressure resists the spring force of the spring 1h. It acts on the cam ring 1a and pushes down the cam ring 1a in the direction shown in the drawing to reduce the cam ring eccentricity. That is, the structure is such that the cam ring eccentricity can be controlled by controlling the cam ring eccentric pressure PF to the cam ring eccentric pressure chamber 1b.

Further, the pump cover 1c is provided with a suction port and a discharge port (not shown), a suction oil passage 7 from an oil pan 6 is connected to the suction port, and a line pressure oil is connected to the discharge port. The path 8 is connected.

The three-way duty solenoid valve 2
Is a normally closed type valve that uses the pilot pressure PP from the pilot valve 5 as a base pressure to generate a solenoid pressure PSL to the pressure reducing valve 3. The valve case 2a has a solenoid coil 2b, a ball valve 2c, etc. built therein. A solenoid pressure port 2d, a pilot pressure port 2e, and a drain port 2f are provided in a valve chamber provided with the ball valve 2c.
Are in communication. The ball valve 2c connects the solenoid pressure port 2d and the pilot pressure port 2e when the solenoid coil 2b is energized and shuts off the drain port 2f when the solenoid coil 2b is turned on. And drain port 2f
Shows the valve operation of connecting the valve and shutting off the pilot pressure port 2e. That is, when a duty command that repeats on / off at a predetermined frequency is output to the solenoid coil 2b, when the duty command has a high duty ratio (high on-time ratio), the solenoid pressure PSL is set to a high pressure and the duty command is low duty. The solenoid pressure PSL is adjusted to a low pressure when the ratio is low (the on-time ratio is low), so that the solenoid pressure PSL is adjusted according to the duty command.

The pressure reducing valve 3 uses the line pressure PL as a base pressure and the solenoid pressure PSL from the three-way duty solenoid valve 2 as an operation signal pressure, and the cam ring eccentric pressure chamber 1b.
Is a valve that produces a cam ring eccentric pressure PF, and a spool 3b is slidably provided in a valve hole 3a. In the valve hole 3a, a solenoid pressure port 3c connected to a solenoid pressure oil passage 11 and a drain port 3d are provided. , Cam ring eccentric pressure port 3 connected to cam ring eccentric pressure oil passage 12
e and the line pressure port 3f connected to the line pressure oil passage 8
And a cam ring eccentric pressure port 3g connected to the cam ring eccentric pressure oil passage 12 via an orifice 13. And in this pressure reducing valve 3, the solenoid pressure PSL
The line pressure PL is reduced according to the pressure level of 0 to regulate the cam ring eccentric pressure PF from 0 to the maximum pressure, and the hydraulic oil due to the cam ring eccentric pressure PF is transferred to the cam ring eccentric pressure chamber 1b via the cam ring eccentric pressure oil passage 12. Supply. Here, when the solenoid pressure PSL rises, the cam ring eccentric pressure PF rises, and the control piston 1f pushes the cam ring 1a with the oil pressure against the spring force of the spring 1h, and the cam ring eccentricity decreases and the line pressure PL is reduced. It

When the solenoid pressure PSL decreases, the cam ring eccentric pressure PF decreases, and the cam ring 1a pushes the control piston 1f by the spring force of the spring 1h against the oil pressure, and the cam ring eccentricity increases and the line pressure PL increases. The pressure is increased.

The three-way duty solenoid valve 1
Reference numeral 4 is a valve that uses the pilot pressure PP from the pilot valve 5 as a base pressure to generate a solenoid pressure PSC to the pressure reducing valve 15, and its specific structure is similar to that of the three-way duty solenoid valve 2.

The pressure reducing valve 15 is a valve that uses the line pressure PL as a base pressure and the solenoid pressure PSC from the three-way duty solenoid valve 14 as an operation signal pressure to generate a clutch pressure PC to the clutch piston chamber (not shown). The specific structure is similar to that of the pressure reducing valve 3.

The pilot valve 5 is a valve that uses the line pressure PL from the variable displacement vane pump 1 as a base pressure to generate a pilot pressure PP for the three-way duty solenoid valves 2 and 14, and the pilot valve 5 has a line pressure PL. Regardless of the pressure level of PL, the pilot pressure PP is adjusted to a constant pressure determined by the setting of the spring force for urging the spool, and hydraulic oil of pilot pressure PP is supplied through a pilot pressure oil passage 10 having a filter 9.

The A / T controller 4 is an electronic controller mainly composed of a microcomputer, and includes an engine speed sensor 4a, a throttle opening sensor 4b (corresponding to vehicle state detecting means), a line pressure sensor 4c, and a cam ring eccentricity sensor. 4d (corresponding to cam ring eccentricity detection means), vehicle speed sensor 4e (corresponding to vehicle state detection means), oil temperature sensor 4f, and the like are input, and are processed by a predetermined line pressure control program and shift hydraulic control program. The duty ratio to be instructed is determined, and the determined duty ratio command is output to each of the three-way duty solenoid valves 2 and 14.

The cam ring eccentricity sensor 4d is shown in FIG.
As shown in FIG. 4, a pin 1g press-fitted into the cam ring 1a and rotatably supported with respect to the pump cover 1c and the pump housing 1m is provided at the end of the pin 1g. As shown in
A sensor voltage proportional to the cam ring eccentricity e is output.

In the A / T controller 4, for example,
As shown in FIG. 5, a shift schedule that defines the optimum gear position by the shift line for the vehicle state determined by the throttle opening and the detected value of the vehicle speed in the shift control is stored in advance.

Next, the operation will be described.

(A) Line Pressure Control Processing FIG. 6 is a flow chart of the main routine showing the flow of the line pressure control processing operation during shifting performed by the A / T controller 4 of the first embodiment system. Each step will be described below. Yes (corresponding to line pressure control means during shifting).

In step 60, it is judged whether or not there is a shift command.

In the gear position determination process (corresponding to the gear position determining means) in the shift hydraulic pressure control program corresponding to the shift hydraulic pressure control means, this shift command is such that the detected values of the throttle opening and the vehicle speed indicate the shift line of the shift schedule. Output when crossing.

In step 61, the shift command reset time T is set to T = 0.

In step 62, the delay time Td setting subroutine is called to set the delay time Td.

In step 63, a command to set the cam ring 1a of the variable displacement vane pump 1 to the maximum eccentric position, that is, a command with a duty ratio of 0% is output to the three-way duty solenoid valve 2.

In step 64, it is determined whether the shift command reset time T is longer than the delay time Td.

At step 65, a command for prohibiting the shift hydraulic pressure control is output.

In step 66, the time obtained by adding the elapsed time ΔT to the previous shift command reset time T is set as the current shift command reset time T.

At step 67, a command for releasing the inhibition of the shift hydraulic pressure control is output.

In step 68, the command to set the cam ring 1a of the variable displacement vane pump 1 to the maximum eccentric position is canceled.

FIG. 7 is a flowchart of a subroutine for setting the delay time Td, and each step will be described below (corresponding to the delay time setting means in claim 2).

In step 62a, it is determined whether the oil temperature Toil is below the set oil temperature Tc.

At step 62b, the delay time Td is
Td is set to 0.

In step 62c, the delay time Td is set by calculation by the following equation which is a function of the throttle opening TH and the engine speed NE.

Td = K1.TH + K2. (1 / NE) K1,
K2; Proportional constant (B) When shifting at low oil temperature When shifting at a low oil temperature where the oil temperature Toil is less than or equal to the set oil temperature Tc, go to step 60 → step 61 → step 62 → step 63 → step 64 → step 67 The delay time Td is set to Td = 0 in step 62, a command for setting the cam ring 1a to the maximum eccentric position is output in step 63, and in step 64, the process directly proceeds to step 67 based on the setting of Td = 0. , Line pressure PL
The shift hydraulic pressure control is executed at the same time with the increase control.

Accordingly, when the automatic transmission hydraulic fluid is at a low temperature and the hydraulic fluid viscosity is high, such as when the vehicle starts in winter or in a cold region, the line pressure increase command during shifting and the shift execution command are issued in response to the output of the shift command. And are done at the same time.

As described above, the delay time Td is set to Td = 0 when the oil temperature is low, because the clutch pressure PC rises longer than the time when the line pressure PL rises after the gear shift command is issued. Is slow and there is no need to worry about a shift shock, and if the oil temperature is low, the delay time
This is because when Td is set, the increase in the engagement force of the clutch 13 that is engaged at the line pressure PL is delayed, and the shift responsiveness is reduced.

(C) Shifting at high oil temperature When shifting at a high oil temperature where the oil temperature Toil exceeds the set oil temperature Tc, step 60 → step 61 → step 62 → step 63 → step 64 → step 65 → step 66
The flow goes to, and in step 62 the delay time
Td is set by a function of the throttle opening TH and the engine speed NE, a command for setting the cam ring 1a to the maximum eccentric position is output in step 63, and the shift hydraulic control is prohibited in step 65. Then, after repeating the flow of steps 64 to 66 for the delay time Td, the routine proceeds from step 64 to step 67, and the shift hydraulic pressure control is executed after the delay time Td from the increase control of the line pressure PL.

When the output of the shift command is completed, the process proceeds from step 60 to step 68, and in step 68,
The increase control of the line pressure PL is released, and the normal line pressure control is restored by feedback control or the like based on the deviation between the target line pressure and the actual line pressure.

The reason why the delay time Td is given as a variable value by a function of the throttle opening TH and the engine speed NE as the line pressure increase control during shifting is obtained by the maximum eccentricity of the cam ring is that the cam ring eccentricity is given. As shown in FIG. 8 (a), the line pressure increase sensitivity to the amount is low when the engine speed NE is small and the line pressure increase sensitivity is low, and the delay time Td must be increased. As described above, when the throttle opening TH is large, the sensitivity of the line pressure increase is low and it is necessary to increase the delay time Td.

Therefore, the respective commands and hydraulic pressures at the time of shifting at a low oil temperature in which the oil temperature Toil exceeds the set oil temperature Tc are as shown in the time chart of FIG. At the time of gear shifting, where the pump load flow rate transiently increases due to the oil consumption due to the oil precharge, the line pressure increase control is performed by increasing the discharge oil amount by the maximum eccentricity of the cam ring. Unlike the case where the control is continued as it is, the precharge time is shortened by the oil amount replenishment, and the shift response can be improved.

Further, since the line pressure increase control at the time of shifting suppresses the decrease of the line pressure PL at the time of shifting, unlike the case where the normal feedback control is continued as it is at the time of shifting, the clutch pressure PC is sufficient at the precharge end timing. The pressure level is reached, and as shown in the clutch pressure characteristic of FIG. 9, the surge immediately after the end of precharge is suppressed, and shift shock can be prevented.

Next, the effect will be described.

(1) Since the cam ring eccentric pressure direct electronic control system is adopted, the pressure regulator valve, the pressure modifier valve, etc. are eliminated and the system can be made compact and lightweight.

(2) The system is stabilized by the electronically controlled cam ring eccentric pressure variable gain system without leaking oil by the bleed orifice, and the number of valves is reduced, so that the efficiency is improved by reducing the oil leak amount. You can

(3) Since the system does not use the pressure regulator valve which is a delay element, the control response of the line pressure is improved.

(4) Shift line pressure control for increasing the cam ring eccentricity to the maximum displacement immediately when a shift command is input, and shift hydraulic pressure control for executing shift at the same time as the shift command or after waiting a predetermined delay time Td. Since it is a hydraulic control system that performs the above, it is possible to improve the shift response and prevent shift shock.

(5) The delay time depends on the oil temperature Toil, the engine speed NE and the throttle opening TH.
Since Td is set, the shift response can be improved and shift shock can be prevented regardless of changes in these conditions.

(Second Embodiment) A hydraulic control system for an automatic transmission according to a second embodiment corresponding to the inventions of claims 3, 4 and 5 will be described.

Since the system configuration is similar to that of the system of the first embodiment shown in FIG. 2, its illustration and description are omitted.

Next, the operation will be described.

(A) Line pressure control process FIG. 10A is a flow chart of the main routine showing the flow of the line pressure control process operation during shifting performed by the A / T controller 4 of the second embodiment system. Each step will be described.

In step 61 ', the shift command reset time T is set to T = 0 and the cam ring eccentricity e
Is read.

At step 62 ', the delay time Td setting subroutine is called to set the delay time Td. In the subroutine shown in FIG. 10B, when the oil temperature Toil exceeds the set oil temperature Tc, the delay time Td is set to the constant value Tdo in step 62d.

At step 63 ', the cam ring eccentricity increment Δe of the variable displacement vane pump 1 is set by the following equation (corresponding to the cam ring eccentricity increment setting means), and the set cam ring eccentricity increment Δe is set. The command that is obtained while monitoring is output.

Δe = k1TH + k2 (1 / NE) k1,
k2; proportional constant In step 68 ', the command to obtain the cam ring eccentricity increment Δe of the variable displacement vane pump 1 is released.

The steps having the same reference numerals as those in FIGS. 6 and 7 are the same processing, and the description thereof will be omitted.

(B) When shifting at low oil temperature When shifting at a low oil temperature where the oil temperature Toil is less than or equal to the set oil temperature Tc, the difference between whether the cam ring eccentricity is given by the maximum eccentricity or by the eccentricity increment Δe Is the same as the first embodiment.

(C) Shifting at high oil temperature When shifting at a high oil temperature in which the oil temperature Toil exceeds the set oil temperature Tc, the same as in the first embodiment except for the following points.

That is, in the second embodiment, the delay time
When Td is given as a constant value Tdo, the cam ring eccentricity in the line pressure increase control during shifting is given as a variable cam ring eccentricity increment Δe by a function of the throttle opening TH and the engine speed NE, and the cam ring eccentricity is also increased. The amount increment Δe is given while monitoring the cam ring eccentricity e by detection.

The reason why the cam ring eccentricity increment Δe is given as a function of the throttle opening TH and the engine speed NE is the same as the setting of the delay time Td in the first embodiment.
This is due to the difference in the line pressure increase sensitivity to the cam ring eccentricity.

Next, the effect will be described.

In addition to the effects (1) to (3) of the system of the first embodiment, the following effects can be obtained.

(4 ') Immediately after the shift command is input, the line pressure control during shifting is performed to increase the cam ring eccentricity by the cam ring eccentricity increment Δe, and shifting is performed after the delay time Td elapses at the same time or at a constant value from the shift command. Because it is a hydraulic control system that performs shift hydraulic control to be executed,
It is possible to improve the shift response and prevent shift shock.

(5 ') The delay time Td is set in accordance with the oil temperature Toil, and the cam ring eccentricity increment Δ is set in accordance with the engine speed NE and the throttle opening TH.
Since e is set, it is possible to improve the shift response and prevent shift shock regardless of changes in these conditions.

(6) Since the cam ring eccentricity e based on the detected value is used as the feedback control information for confirming the cam ring eccentricity increment Δe, the line pressure during shifting is prevented to prevent the line pressure from decreasing due to the increase in the cam ring eccentricity. The control accuracy of control can be improved.

Although the embodiment has been described with reference to the drawings, the specific configuration and control contents are not limited to the embodiment.

For example, in the embodiment, as the control actuator, the actuator in which the three-way duty solenoid valve and the pressure reducing valve are separate bodies is shown, but a duty solenoid valve integrated with the pressure reducing valve may be used. Alternatively, a proportional solenoid valve may be used.

In the embodiment, as the shift hydraulic pressure control device, a device for directly controlling the line pressure by the control valve is shown, but as described in the prior art, a device using a shift solenoid or a shift valve may be used.

[0100]

According to the invention of claim 1, in the hydraulic control system of the automatic transmission, the line pressure is controlled by direct electronic control of the cam ring eccentric pressure to the variable displacement vane pump, and the shift command is input. Since the line pressure control means for immediately changing the cam ring eccentricity and the shift hydraulic pressure control means for executing the shift after waiting a predetermined delay time from the shift command are provided, the line pressure control can be reduced in size, weight and efficiency. It is possible to obtain the effect that the shift response can be improved and the shift shock can be prevented while achieving the improvement of the speed and the control response.

According to the second aspect of the invention, in the hydraulic control system for the automatic transmission, the delay time setting means is
When the oil temperature is below the set temperature, the delay time is set to zero time, and when the oil temperature exceeds the set temperature, the delay time is set as a function of the engine speed and throttle opening. It is possible to obtain an effect that the gear shift response can be improved and the gear shift shock can be prevented regardless of the opening degree.

According to the third aspect of the invention, in the hydraulic control system for the automatic transmission, the cam ring eccentricity amount detecting means for estimating the specific discharge amount from the variable displacement vane pump is provided, and the line pressure control means during shifting is provided. The means for using the detected value of the cam ring eccentricity amount as feedback control information for confirming the increment amount of the cam ring eccentricity amount which is increased at the time of shifting, so that the line pressure control accuracy at the time of shifting can be improved. The effects of the invention described can be achieved.

According to another aspect of the invention, in the hydraulic control system for an automatic transmission, the increment of the cam ring eccentricity that is increased during a shift is set by a function of the engine speed when a shift command is input. Since the cam ring eccentricity increment setting means is provided, the effect of the invention according to claim 3 can be achieved regardless of the engine speed.

[Brief description of drawings]

FIG. 1 is a claim correspondence diagram showing a hydraulic control system for an automatic transmission according to the present invention.

FIG. 2 is an overall system diagram showing a hydraulic control system for an automatic transmission according to a first embodiment.

FIG. 3 is a sectional view of a cam ring pivot portion of the first embodiment device.

FIG. 4 is an output characteristic diagram of a cam ring eccentricity amount sensor.

FIG. 5 is an example of a shift schedule in the shift hydraulic control system according to the first embodiment.

FIG. 6 is a flowchart of a main routine showing a flow of a shift line pressure control processing operation performed by the A / T controller of the first embodiment system.

FIG. 7 is a flowchart of a subroutine showing a flow of a delay time setting process operation performed by the A / T controller of the first embodiment system.

FIG. 8 (a) is a line pressure characteristic diagram for the cam ring eccentricity amount with the engine speed as a parameter, and FIG. 8 (b) is a line pressure characteristic diagram for the cam ring eccentricity amount with the throttle opening as a parameter. is there.

FIG. 9 is a time chart showing each command value characteristic, line pressure characteristic, and clutch pressure characteristic at the time of shifting.

FIG. 10A is an A / T of the second embodiment system.
It is a flow chart of the main routine showing the flow of the line pressure control processing operation during shifting performed by the controller,
FIG. 10B is a flowchart of a subroutine showing the flow of the delay time setting processing operation performed by the A / T controller.

FIG. 11 is a time chart showing shift command characteristics, line pressure characteristics, and clutch pressure characteristics in the conventional system.

[Explanation of symbols]

 a cam ring b cam ring eccentric pressure chamber c variable displacement vane pump d eccentric pressure control actuator e fastening element f fastening pressure control actuator g vehicle state detection means h shift schedule i gear position determination means j shift time line pressure control means k delay time setting means m Speed change hydraulic control means n Cam ring eccentricity detection means p Cam ring eccentricity increment setting means

Claims (4)

[Claims] 1. A variable displacement vane pump having a cam ring eccentric pressure chamber for controlling the eccentricity of a cam ring according to the magnitude of the hydraulic pressure, and an eccentric pressure control actuator for controlling the hydraulic pressure to the cam ring eccentric pressure chamber by an external command. And a fastening pressure control actuator that controls the fastening element pressure to the fastening element based on the line pressure discharged from the variable displacement vane pump according to an external command, and a shift that is set with a detection value from the vehicle state detection means. A gear position determination means for determining the gear position according to the schedule, and a control command for increasing the cam ring eccentricity immediately when a shift command output from the gear position determination means is input when the vehicle state detection value crosses the shift line of the shift schedule. Line pressure control means during shifting, which outputs to the eccentric pressure control actuator; A delay time setting means for setting a predetermined delay time when a shift command is input from the position determining means, and a shift execution command for engaging the gear position fastening element after shifting after waiting for the time set by the delay time setting means. A hydraulic pressure control system for an automatic transmission, comprising: a shift hydraulic pressure control means for outputting to the engagement pressure control actuator. 2. The hydraulic control system for an automatic transmission according to claim 1, wherein the delay time setting means sets the delay time to zero time when the oil temperature is equal to or lower than a set temperature, and sets the delay time when the oil temperature exceeds the set temperature. A hydraulic control system for an automatic transmission, characterized in that is set as a function of engine speed and throttle opening. 3. The hydraulic control system for an automatic transmission according to claim 1, further comprising cam ring eccentricity amount detection means for estimating a specific discharge amount from the variable displacement vane pump, the shift line pressure. A hydraulic control system for an automatic transmission, characterized in that the control means is means for using a detected cam ring eccentricity amount as feedback control information for confirming an increment amount of the cam ring eccentricity amount that is increased during gear shifting. 4. The hydraulic control system for an automatic transmission according to claim 3, wherein the increment of the cam ring eccentricity that is increased during gear shifting is
A hydraulic control system for an automatic transmission comprising cam ring eccentricity increment setting means for setting a function of an engine speed when a shift command is input.