JP2999589B2 - Hydraulic control device for automatic transmission - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic control device for an automatic transmission, and more particularly, to a shift control using excess hydraulic oil discharged from hydraulic pressure adjusting means such as a regulator valve for adjusting a line pressure supplied to a frictional engagement element. The present invention relates to a hydraulic control device that lubricates each part of a gear mechanism.

[0002]

2. Description of the Related Art Generally, automatic transmissions mounted on vehicles are
Combining a torque converter and a transmission gear mechanism, switching the power transmission path of this transmission gear mechanism by the selective operation of a plurality of frictional engagement elements such as clutches and brakes,
The automatic transmission is configured to automatically shift to a predetermined gear. This type of automatic transmission is provided with a hydraulic control circuit that controls supply and discharge of hydraulic pressure to and from actuators of the friction engagement elements. Specifically, this hydraulic control circuit includes:
A regulator valve that adjusts the discharge pressure of the oil pump driven by the engine to a predetermined line pressure is provided, and various valves such as a manual valve and a shift valve are installed downstream of the regulator valve. Become.

[0003]

By the way, in this type of automatic transmission, surplus hydraulic oil discharged from the regulator valve is supplied as lubricating oil to a sliding portion of a transmission gear mechanism. ing. In such a case, at a high oil temperature at which the viscosity of the hydraulic oil decreases, the amount of leak at the downstream side of the regulator valve increases, and the hydraulic oil is consumed to compensate for this and maintain a constant line pressure. In addition, there is a problem that the amount of hydraulic oil discharged from the regulator valve decreases, the amount of lubricating oil becomes insufficient, and the lubricating performance deteriorates.

SUMMARY OF THE INVENTION The present invention addresses the above-mentioned problem in an automatic transmission in which excess hydraulic oil discharged from operating hydraulic pressure adjusting means such as a regulator valve is used as lubricating oil. The purpose is to avoid lack of oil.

In Japanese Utility Model Laid-Open Publication No. 61-133150, an oil temperature detecting device for detecting the oil temperature of the automatic transmission is provided, and the oil temperature detected by the oil temperature detecting device is lower than a predetermined value. Sometimes the line pressure is switched to the high oil pressure side, but this is intended to improve the responsiveness at low oil temperature where the viscosity of the hydraulic oil is low, and insufficient lubrication at high oil temperature. The technical purpose to be solved is completely different from the present application for avoidance.

[0006]

That is, in the hydraulic control apparatus for an automatic transmission according to the first aspect of the present invention (hereinafter referred to as the first aspect), as shown in FIG. a speed change gear mechanism B ₂ inputted via the converter B _1, the power transmission path speed change gear mechanism B ₂ by selectively fastening a plurality of frictional engagement elements provided in the transmission gear mechanism B ₂ and it provided in the hydraulic control circuit actuating the hydraulic adjusting means B ₃ for adjusting the pressure of the operating oil supplied to the frictional engagement elements for switching, to be driven by the engine a to generate a working oil pressure supplied to the hydraulic control circuit It provided with a hydraulic generating unit B _4, in that so as to lubricate the speed change gear mechanism B ₂ using the hydraulic oil discharged from the hydraulic pressure adjusting means B _3, the oil temperature for detecting the temperature of the hydraulic oil Detection means C, and when working oil temperature is higher than a predetermined temperature detected by the detecting means C, said predetermined
Low pressure operation compared to when the operating oil temperature is lower than the constant temperature
Hydraulic pressure is characterized by providing a hydraulic pressure control means D to operate the urchin the hydraulic pressure adjusting means B ₃ O Ru is supplied to the frictional engagement elements.

The invention of claim 2 of the present application (hereinafter referred to as “second
Hydraulic control device for an automatic transmission according to the present invention hereinafter), as in the first invention, the transmission gear mechanism B ₂ to the output of the engine A is inputted through a torque converter B _1, the transmission gear mechanism B ₂ a plurality of pressure of hydraulic oil provided to the hydraulic control circuit for switching the power transmission path speed change gear mechanism B ₂ is supplied to the frictional engagement element by the frictional engagement element to be selectively fastened provided adjustment a hydraulic pressure adjusting means B ₃ for, along with being driven by the engine a in and an oil pressure generating means B ₄ for generating the operating oil pressure supplied to the hydraulic control circuit, operated discharged from the hydraulic pressure adjusting means B ₃ using an oil in that so as to lubricate the speed change gear mechanism B _2, provided an oil temperature detecting means C for detecting the temperature of the hydraulic oil. As shown by a chain line in FIG. 1, an engine output detecting means E for detecting the output of the engine A is provided. When the engine output detected by the detecting means E is equal to or less than a predetermined value, the oil temperature detecting means C when hydraulic oil temperature detected is higher than a predetermined temperature, providing a hydraulic pressure control unit D for working oil pressure supplied to the frictional engagement element actuates the actuating oil pressure adjusting portion B ₃ to decrease.

Further, in the hydraulic control apparatus for an automatic transmission according to the invention of claim 3 of the present application (hereinafter, referred to as a third invention), similarly to the first invention, the output of the engine A is transmitted via the torque converter B ₁ . a speed change gear mechanism B ₂ inputted Te, the hydraulic control circuit for switching the power transmission path speed change gear mechanism B ₂ by selectively fastening a plurality of frictional engagement elements provided in the transmission gear mechanism B ₂ and provided with hydraulic pressure adjusting means B ₃ for adjusting the pressure of the operating oil supplied to the frictional engagement elements, hydraulic pressure generating means B ₄ for generating a hydraulic pressure that is driven by Enjin'a supplied to the hydraulic control circuit provided with a preparative, using the hydraulic oil discharged from the hydraulic pressure adjusting means B ₃ in that so as to lubricate the speed change gear mechanism B _2, the oil temperature detecting means C for detecting the temperature of the hydraulic oil Provide. Then, as the engine output, the engine speed detecting means E ₁ and the engine load detecting means E ₂ respectively detect the engine speed and the engine load is provided, the engine speed detected by these detection means E _1, E ₂ and equal to or less than the predetermined value and the engine load, respectively, when the working oil temperature is higher than the predetermined temperature, hydraulic pressure of working oil pressure supplied to the frictional engagement element actuates the actuating oil pressure adjusting portion B ₃ to decrease Control means D is provided.

[0009]

According to the above arrangement, in any of the first to third aspects, when the hydraulic oil temperature is lower than the set temperature,
Since the operating oil pressure supplied to the friction engagement element is maintained at a predetermined line pressure, the responsiveness at the time of low oil temperature is not impaired.

According to the first aspect , when the operating oil temperature rises above the set temperature, the operating oil pressure supplied to the frictional engagement element is reduced, so that the amount of operating oil leak decreases. At the same time, the amount of hydraulic oil discharged to the lubrication system also increases. Therefore, a sufficient amount of lubricating oil can be ensured even at a high oil temperature.

[0011] According to the second invention, even if hydraulic oil temperature has exceeded the set temperature, the engine output state quantity so that the working oil pressure started when lower than the predetermined value is reduced, high Deterioration of the responsiveness in the output state is avoided.

In particular, according to the third invention, the operating oil pressure is reduced when both the engine load as the engine output and the engine speed fall below the predetermined values, respectively. Similarly, deterioration of the responsiveness in the high output state is avoided.

[0013]

Embodiments of the present invention will be described below.

As shown in FIG . 2 , a throttle valve 5 which operates in conjunction with an accelerator pedal (not shown) is provided in an intake passage 4 of an engine 3 which constitutes a power plant 2 together with the automatic transmission 1. In the middle of a bypass passage 6 that bypasses the throttle valve 5,
An idle speed control valve (hereinafter, referred to as an ISC valve) 7 for controlling an engine speed by adjusting an intake air amount is provided.

Meanwhile, also the automatic transmission 1 constituting the power plant 2, as shown in FIG. 3, the engine 3
A torque converter 20 connected to the output shaft 8 of the vehicle, a transmission gear mechanism 30 to which the output torque is input,
A plurality of frictional engagement elements 41 to 46 and one-way clutches 51 and 52 such as clutches and brakes for switching the power transmission path 0, and a hydraulic control circuit 60 for controlling the supply and discharge of the line pressure supplied to the frictional engagement elements 41 to 46. And

[0016] The torque converter 20 includes a pump 2 which is fixed in a case 21 which is connected to the engine output shaft 8
2, a turbine 23 disposed opposite to the pump 22,
A stator 25 supported by the transmission case 9 via a one-way clutch 24 to increase the torque;
1 and a lock-up clutch 26 interposed between the turbine 1 and the turbine 23. The rotation of the turbine 23 is output to the transmission gear mechanism 30 via the turbine shaft 27. Here, a pump shaft 10 penetrating through the turbine shaft 27 is connected to the engine output shaft 8, and the oil pump 11 provided at the rear end of the transmission is driven by the shaft 10.

Meanwhile, the speed change gear mechanism 30 is constituted by a known Rapinyo type planetary gear device, the turbine shaft 27 loosely engaged the small-diameter small sun gear 3 on
1 and a large-diameter large sun gear 32 loosely fitted on the turbine shaft 27 also behind the sun gear 32.
A plurality of short pinion gears 33 meshed with the small sun gear 31, a front half of which is meshed with the pinion gear 33 and a rear half of which is the large sun gear 3.
2, a long pinion gear 34, a carrier 35 rotatably supporting the long pinion gear 34 and the short pinion gear 33, and a ring gear 36 meshed with the front half of the long pinion gear 34.

A forward clutch 41 and a first one-way clutch 51 are connected in series between the turbine shaft 27 and the small sun gear 31, and a coast clutch 42 is provided in parallel with the clutches 41 and 51. A 3-4 clutch 43 is interposed between the turbine shaft 27 and the carrier 35, and the turbine shaft 27 and the large sun gear 3
2, a reverse clutch 44 is interposed. Further, between the large sun gear 32 and the reverse clutch 44, a 2-4 brake 45 which is a band brake for fixing the large sun gear 32 is provided, and between the carrier 35 and the transmission case 9 is provided. , A second one-way clutch 52 for receiving the reaction force of the carrier 35
And a low reverse brake 46 for fixing the carrier 35
And are provided in parallel. And the ring gear 3
The rotational power is output via an output gear 12 connected to the motor 6.

[0019] To summarize the relationship between the above operation the gear of the respective frictional engagement elements 41 to 46 and the one-way clutch 51, becomes as shown in Table 1 below.

[0020]

[Table 1] As shown in FIG. 2 , the power plant 2 is provided with a control unit 70 for integrally controlling the engine 3 and the automatic transmission 1. The control unit 70 detects the opening of the throttle valve 5. A signal from a throttle opening sensor 71, a signal from an idle switch 72 for detecting the fully closed state of the throttle valve 5, a signal from an engine speed sensor 73 for detecting the speed of the engine output shaft 8, and a torque A signal from a turbine speed sensor 74 for detecting the output speed (turbine speed) of the converter 20 and a signal from an output speed sensor 75 for detecting the output speed of the transmission gear mechanism 30 representing the vehicle speed of the vehicle. And a range sensor 76 for detecting a select position (range) by the select lever 13
And a temperature sensor 77 for detecting the temperature of the hydraulic oil
And the signal from the engine 3
The engine rotation control by the C valve 7 and the speed change solenoid valves 78... 78 provided in the hydraulic control circuit 60
, And line pressure control by a duty solenoid valve 79 also provided in the hydraulic control circuit 60.

[0021] Next, the portion related to the line pressure control in the hydraulic control circuit 60.

As shown in FIG. 4 , the hydraulic control circuit 60 includes a regulator valve 61 for adjusting the pressure of the hydraulic oil discharged from the oil pump 11 to a predetermined line pressure.
A throttle modulator valve 62 for supplying a control pressure to the regulator valve 61 is provided. The throttle modulator valve 62 has a reducing valve 64 for reducing the operating oil to a constant pressure from a main line 63 through which the operating oil is discharged from the oil pump 11.
Is connected to a constant pressure line 65 led through the line.
Further, a pressure increasing port 6 provided from the throttle modulator valve 62 to one end of the regulator valve 61 is provided.
1a, a pressure increasing line 66 is guided, and a pilot line 67 branched from the constant pressure line 65 is connected to a control port 6 at one end of the throttle modulator valve 62.
2a.

[0023] Then, on the pilot line 67,
The duty solenoid valve 79 for line pressure control shown in FIG. 2 is installed, and the duty ratio of the duty solenoid valve 79 (ON during the ON-OFF cycle)
(A time ratio) is introduced into the control port 62a of the throttle modulator valve 62, so that the constant pressure supplied from the constant pressure line 65 becomes a pressure corresponding to the pilot pressure or the duty ratio. This pressure is adjusted to be supplied to the pressure increasing port 61a of the regulator valve 61 via the pressure increasing line 66. Therefore, this regulator valve 6
The line pressure adjusted by 1 is a pressure corresponding to the duty ratio.

Further , a torque converter line 68 connected to a drain port 61b provided at an intermediate portion of the regulator valve 61 is connected to the torque converter 20, so that excess hydraulic oil discharged from the regulator valve 61 Through the converter 20, lubricating oil is supplied to each part of the transmission gear mechanism 30.

Next, explaining by the control unit 70, which is a feature of the present embodiment the line pressure control for, control the line pressure is performed as follows according to the flowchart of FIG.

[0026] In other words, the control unit 70,
After reading various signals in step S1, step S1
At 2, it is determined whether or not the gear is a normal shift. That is, the control unit 70 reads the output rotation speed and the throttle opening of the transmission gear mechanism 30 and sets the output rotation speed and the throttle opening in a transmission line in which the output rotation speed and the throttle opening are set in advance as parameters. According to the configured shift pattern, a shift determination is performed when the operating state exceeds the shift line.

When the control unit 70 determines that the shift is not a normal shift, the process proceeds to step S3 to determine whether or not the shift is a manual shift by operating the select lever 13. When it is determined that the shift is not a manual shift, the process proceeds to step S4. in the throttle opening theta it is determined whether a predetermined low-load decision value theta ₀ smaller than when the open degree theta is determined to not less than the low load judging value theta ₀ shifts to step S5, FIG. As shown in FIG. 6 , a map of the target line pressure set in advance in accordance with the throttle opening indicates the actual throttle opening θ.
To calculate the target line pressure P _L corresponding to the throttle opening θ. Here, the target line pressure P _L is set to increase as the throttle opening θ increases.

[0028] Subsequently, the procedure proceeds to the control unit 70 step S6, the map of the duty ratio which is set in advance target line pressure P _L as a parameter as shown in FIG. 7, the target line pressure P _L calculated in step S5 In addition to calculating the applied duty ratio D, step S
A duty signal corresponding to the duty ratio D calculated in 7 is output to the duty solenoid valve 79. Therefore, a line pressure corresponding to the throttle opening θ representing the engine load is generated by the regulator valve 61.

On the other hand, the control unit 70 in step S4 the throttle opening θ is low load determination value θ
_If it is determined that it is smaller than ₀ , the process proceeds to step S8, and it is determined whether or not an idle signal indicating that the throttle valve 5 is fully closed is output from the idle switch 72. This is for reliably determining the low load state of the engine 3.

When the control unit 70 determines that the above conditions are satisfied, the process proceeds to step S9, where the operating oil temperature T input from the oil temperature sensor 77 is set to a predetermined set temperature T ₀ (eg, 120). ° C.) to determine whether it exceeds a, it is determined whether the engine rotational speed N _E is predetermined judgment rotation speed N ₀ (e.g. 610Rpm) lower than in step S10 when the result of determination is YES, the engine speed when the number N _E is determined to be lower than the judgment rotation speed N _0, proceeds to advance hydraulic oil temperature as shown in FIG. 8 in the map of the target line pressure P _L is set as a parameter in the step S11, the operation of the real The target line pressure P _L corresponding to the operating oil temperature T is calculated by comparing the oil temperature T. In this case, the target line pressure P _L is set so as to be kept constant as the hydraulic oil temperature T rises, and to decrease linearly when the temperature exceeds a predetermined temperature, as shown by the solid line in the figure. I have. Then, in the R range where the reduction ratio is large, in order to secure the torque transmission capacity, as shown by the broken line in the figure,
Target line pressure P _L is relatively high set in comparison with the other ranges.

When the target line pressure P _L is obtained in this way, the control unit 70 executes
In steps S6 and S7, a duty ratio D corresponding to the target line pressure P _L is calculated, and a duty signal corresponding to the calculated duty ratio D is output to the duty solenoid valve 79.

The control unit 70 branches to step S12 to calculate the target line pressure P _L at the time of the normal shift when it is determined at step S2 that the shift is the normal shift. The process branches to S13 to calculate a target line pressure P _L at the time of manual shifting.

[0033] Thus, in the operating condition of the engine 3 as a low rotation low load, when the working oil temperature T exceeds the set temperature T _0, since the target line pressure P _L is set low, the hydraulic control circuit 60 , The amount of hydraulic oil leaked decreases, and the amount of hydraulic oil discharged to the lubrication system also increases. Therefore, a sufficient amount of lubricating oil can be ensured even at a high oil temperature.

On the other hand, when the working oil temperature T is lower than the set temperature T _0, since the line pressure according to the throttle opening is obtained, that no impaired response property at a low oil temperature.

[0035]

As described above, according to the present invention, when the operating oil temperature is lower than the set temperature, the operating oil pressure supplied to the friction engagement element is maintained at a predetermined line pressure. Responsiveness at oil temperature is not impaired.

[0036] Then, according to the first invention, when the working oil temperature rises above the set temperature, because the working oil pressure supplied to the frictional engagement element is to be reduced, leakage amount of the hydraulic fluid decreases At the same time, the amount of hydraulic oil discharged to the lubrication system also increases. Therefore, a sufficient amount of lubricating oil can be ensured even at a high oil temperature.

Further, according to the second invention, even if hydraulic oil temperature has exceeded the set temperature, the engine output state quantity so that the working oil pressure started when lower than the predetermined value is reduced, high Deterioration of the responsiveness in the output state is avoided.

In particular, according to the third aspect of the invention, when both the engine load as the engine output and the engine speed fall below the predetermined values, the operating oil pressure is reduced. Similarly, deterioration of the responsiveness in the high output state is avoided.

[Brief description of the drawings]

FIG. 1 is a functional block diagram showing the overall configuration of the present invention.

FIG. 2 is a system configuration diagram of a control system of the present embodiment.

FIG. 3 is a skeleton diagram showing a mechanical configuration of the automatic transmission.

FIG. 4 is a circuit diagram showing a main part of a hydraulic control circuit.

FIG. 5 is a flowchart illustrating line pressure control, which is a characteristic part of the present embodiment.

FIG. 6 is an explanatory diagram of a map for setting a target line pressure according to a throttle opening.

FIG. 7 is an explanatory diagram of a map for obtaining a duty ratio.

FIG. 8 is an explanatory diagram of a map for setting a target line pressure according to a hydraulic oil temperature.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Automatic transmission 3 Engine 11 Oil pump 20 Torque converter 30 Transmission gear mechanism 41-46 Friction fastening element 60 Hydraulic control circuit 61 Regulator valve 70 Control unit 71 Throttle opening sensor 72 Idle switch 73 Engine speed sensor 77 Oil temperature sensor

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kazuo Sasaki 3-1 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Inside Mazda Corporation (72) Inventor Hiroshi Takada 3-1 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Mazda (56) References JP-A-1-307552 (JP, A) JP-A-63-23053 (JP, A) JP-A-4-66337 (JP, A) JP-A-4-203224 (JP, A) A) JP-A-64-35162 (JP, A) JP-A-49-26663 (JP, A) JP-A-3-125067 (JP, A) JP-A-2-57729 (JP, U) (58) Survey Field (Int.Cl. ⁷ , DB name) F16H 59/00-63/48

Claims (3)

(57) [Claims] 1. A power transmission path of a speed change gear mechanism by selectively engaging a speed change gear mechanism to which engine output is input via a torque converter and a plurality of frictional engagement elements provided in the speed change gear mechanism. Hydraulic pressure adjusting means for adjusting the pressure of hydraulic oil supplied to the frictional engagement element, provided in the hydraulic control circuit for switching the pressure, and hydraulic pressure generation for generating operating hydraulic pressure driven by the engine and supplied to the hydraulic control circuit Means for lubricating the transmission gear mechanism using hydraulic oil discharged from the hydraulic oil pressure adjusting means, wherein the oil temperature for detecting the temperature of the hydraulic oil is provided. Detecting means, when the operating oil temperature detected by the detecting means is higher than a predetermined temperature , compared with when the operating oil temperature is lower than the predetermined temperature.
Hydraulic control device for an automatic transmission low pressure hydraulic fluid pressure, characterized in that the the hydraulic pressure control means for operating by Uni the hydraulic pressure adjusting means Ru is supplied to the frictional engagement elements are provided. 2. A power transmission path of the transmission gear mechanism by selectively engaging a transmission gear mechanism to which engine output is input via a torque converter and a plurality of frictional engagement elements provided on the transmission gear mechanism. Hydraulic pressure adjusting means for adjusting the pressure of hydraulic oil supplied to the frictional engagement element, provided in the hydraulic control circuit for switching the pressure, and hydraulic pressure generation for generating operating hydraulic pressure driven by the engine and supplied to the hydraulic control circuit Means for lubricating the transmission gear mechanism using hydraulic oil discharged from the hydraulic oil pressure adjusting means, wherein the oil temperature for detecting the temperature of the hydraulic oil is provided. Detecting means, an engine output detecting means for detecting an engine output, and an engine output detected by the detecting means being equal to or less than a predetermined value and being detected by the oil temperature detecting means. Operating oil pressure control means for operating the operating oil pressure adjusting means such that when the operating oil temperature is higher than a predetermined temperature, the operating oil pressure supplied to the friction engagement element is reduced. Automatic transmission hydraulic control device. 3. A power transmission path of the transmission gear mechanism by selectively engaging a transmission gear mechanism to which engine output is input via a torque converter and a plurality of frictional engagement elements provided in the transmission gear mechanism. Hydraulic pressure adjusting means for adjusting the pressure of hydraulic oil supplied to the frictional engagement element, provided in the hydraulic control circuit for switching the pressure, and hydraulic pressure generation for generating operating hydraulic pressure driven by the engine and supplied to the hydraulic control circuit Means for lubricating the transmission gear mechanism using hydraulic oil discharged from the hydraulic oil pressure adjusting means, wherein the oil temperature for detecting the temperature of the hydraulic oil is provided. Detecting means, engine speed detecting means for detecting the engine speed, engine load detecting means for detecting the engine load, When the engine speed and the engine load are below a predetermined value and the operating oil temperature is higher than the predetermined temperature, the operating oil pressure adjusting means is operated so that the operating oil pressure supplied to the friction engagement element is reduced. And a hydraulic control unit for operating the automatic transmission.