JPS6110169A - Hydraulic control device for automatic speed change gear - Google Patents

Abstract

PURPOSE:To cool plates and discs of a clutch and a brake by opening a check valve for supplying line pressure to a speed change control device of a fluid- type automatic speed change gear by a speed change decision device. CONSTITUTION:A computer 20 which is a speed change decision portion of an automatic speed change gear is operated according to signals of a throttle valve opening, a rev. number of an engine and a shift position of a shift lever, so that a solenoid 21 is driven to open and close a check valve 22. Accordingly, at the time of changing speed, a large quantity of oil flows into a multidisc clutch and a multidisc brake to restrain a surface temperature rise of the disc and plate.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention This invention relates to a hydraulic control system for an automatic transmission used in automobiles.

BACKGROUND ART Conventionally, as shown in FIG. 5, a hydraulic automatic transmission installed in an automobile usually includes a torque converter 8 driven by an output shaft 40 of a vehicle engine, and a speed change gear device 13 operated by hydraulic pressure. It consists of The transmission gear device 13 includes a third speed section 14 and an overdrive section 16.
is provided. As shown in this figure, multi-disc brakes 14b and 14c are used in the third speed section 14,
Also, multi-disc clutches 14a and 14d are used. The overdrive section 16 also has a multi-disc brake 16a.
and multi-disc clutch 16. b is used. These multi-disc clutches and multi-disc brakes have a plurality of discs (not shown) and a plurality of plates (not shown) arranged alternately. In order to achieve both high output and 8-rpm automobile engines and to achieve both fuel efficiency and power performance, the gear ratios of transmission gears have become wider. The heat load on the discs and plates of multi-disc clutches and multi-disc brakes used in equipment during gear changes tends to increase rapidly.

On the other hand, generally (a) the number of discs and plates used in multi-disc clutches (brakes) is increased. (b) Increase the size of the disk or plate. (c) By taking measures such as increasing the amount of lubricating oil supplied to the transmission gear system in order to cool the discs and plates, the temperature rise on the disc surface of multi-disc clutches and multi-disc brakes can be prevented and their durability improved. Measures are being taken to ensure this.

However, among the above-mentioned conventional measures to prevent temperature rise of multi-disc clutches and multi-disc discs, (a) and (b) increase the weight and size of the automatic transmission, increase the cost, and even make it difficult to operate. In multi-disc clutches and multi-disc brakes, power loss due to drag between the discs and plates will increase. In addition, in (c), as in (a) and (b), power loss due to grinding and oil agitation in various parts through oil between the disk and plate, increase in oil heat generation, and oil becoming foamy. As a result, problems such as oil blowing out from the breather part may occur due to an increase in internal pressure.

Purpose of the Invention In view of the above, the present invention has been made to increase the number and shape of the discs and plates of multi-disc clutches and multi-disc brakes. It is possible to avoid increasing the load on the hydraulic pump and increase its dynamic loss, and to suppress the excessive rise in surface temperature of the discs and plates of multi-disc clutches and multi-disc brakes during gear shifting of automobiles. Play I~
The object of the present invention is to provide a lubricating oil control device for a hydraulic automatic transmission for an automobile, which is capable of preventing power loss due to oil dragging, and further preventing problems such as oil blowing out from a breather section.

Structure of the Invention To achieve the above object, the present invention provides a hydraulic system for an automatic transmission including a fluid coupling and a gear transmission mechanism with a plurality of frictional engagement devices for obtaining several gear stages. The control device includes a hydraulic pressure source, a line hydraulic pressure control valve that generates line hydraulic pressure regulated from the hydraulic pressure source, a shift determining section that determines the shifting of the automatic transmission, and an on/off control based on the determination of the shifting determining section. , a solenoid valve that is turned off, and a switching valve that is controlled by hydraulic pressure supplied from the solenoid valve and selectively supplies lubricating oil to the frictional engagement device.

In the above configuration, when the shift determining section determines that a shift is to be performed during a shift of the automobile, the shift determining section turns on (or turns off) the solenoid valve. When the solenoid valve is turned on (or off), hydraulic pressure is applied to the switching valve, and from the switching valve,
A large amount of high-pressure lubricating oil is directly supplied to the frictional engagement device of the gear transmission III structure. After the gear shift is completed and the frictional engagement device is sufficiently cooled by many lubricating oils, the normal f
It becomes a slippery state.

Embodiments Next, the present invention will be explained based on embodiments shown in the drawings.

FIG. 1 shows the main parts of a shift control system for an automatic transmission for an automobile, and an oil pump 1 driven by an engine has its suction side connected to a strainer 2 located in an oil pan 3. The primary regulator valve 4 is connected to the oil line 5 of the oil pump 1, and adjusts the pressure (hereinafter referred to as line pressure) to the oil pressure sent from the oil pump 1.
do. 'JA pressure is applied by the primary regulator valve 4.1. The Ni-line hydraulic pressure is supplied to the torque converter 8 through the first passage 6 and the second passage 7, and is also supplied to the secondary regulator valve 10 from the third passage 9 branched from the second passage 7. The third passage 9 has an aperture 1.
A fifth passage 15 communicating with the third speed section 14 of the transmission control device 413 and an overdrive section 1 of the transmission control device 13 are connected to this fourth passage 12.
A sixth passage 17 communicating with the differential gear 18 and a seventh passage 19 communicating with the differential gear 18 are connected.
(see figure).

<E, the fourth passage 12 is the passage 3 having the orifice 40
9, it is also connected to other parts 36 of the speed change control device 13.

Electronic condrol transmission (
The computer 20 (hereinafter referred to as ECT) is configured to receive information regarding the opening degree θ of the throttle valve, the engine speed Ne, the vehicle speed ■, the shift lever position SD, and the like. The solenoid 21 is known per se and is driven by the ECT computer 20.
A check valve 22 is opened and closed. That is, the input boat 22a of the check valve 22 is connected to the eighth passage 23, which is connected to the oil passage 5.
a ninth passage 2 branching from 3 and having an orifice 25;
4 is connected above the valve element 22b of the check valve 22. The solenoid 21 opens and closes the ninth passage 24 on the downstream side of the orifice 25.
When turned on, the drain from the hydraulic solenoid 21 in the ninth passage 24 is closed, and the oil at line pressure PL reaches the upper part of the valve element 22b of the check valve 22, causing the valve elements 22 and b to be biased by the biasing force of the spring 22c. Push down against the input boat 22.
Since the port a and the exit boat 22d are communicated with each other, line pressure PL flows through the exit boat 22d.

Then, when the solenoid 21 is turned off, the ninth passage 24
hydraulic pressure drains from the solenoid 21 and the check valve 22
The input boat 22a and the output boat 22d are in communication with each other,
Therefore, oil does not flow into this outlet boat 22d. In FIG. 1, the solenoid 21 is off on the left side of the center and on on the right side, and the check valve 22 is closed on the left side of the center and closed on the right side.

A tenth passage 26 is provided in the outlet boat 22d of the check valve 22.
This tenth passage 26 is connected to the third speed section 14.
The fifth passage 15 of the overdrive section 16 and the sixth passage 17 of the overdrive section 16
are connected to each. The fifth passage 15 has an orifice 2 upstream from the connection part with the tenth passage 26.
7 and a check valve 28 are provided respectively, and a tenth passage 26
An orifice 29 is provided on the downstream side of the connection portion with.

Further, the sixth passage 17 is provided with an orifice 30 and a check valve 31 on the upstream side of the connection with the tenth passage 26, and an orifice 32 on the downstream side of the connection. Note that an orifice 33 is also provided in the seventh passage 19. The orifices 27 and 32 are for adjusting the amount of oil flowing from the fourth passage 12 into the 3rd gear section 14 and the A-patribe section 16 at times other than when changing gears, and the orifices 29 and 32 are for adjusting the amount of oil flowing from the fourth passage 12 into the 3rd gear section 14 and the A-patribe section 16 when changing gears. When line pressure PL flows from the tenth passage 26 in addition to the fourth passage 12, the third speed section 14 and the overdrive section 1
This is to ensure that the amount of oil flowing into each tank (m) is appropriate.

In the above configuration, when the car is running, the oil discharged from the oil pump 1 reaches the primary regulator valve 4 via the oil path 5, and the oil whose pressure is regulated by the valve 4 to the line pressure PL is transferred to the primary regulator valve 4. The oil is sent through the first passage 6 and the second passage 7 to the torque converter 8 side, and flows from the third passage 9 through the secondary regulator valve 10 and the orifice 11 to the fourth passage 12, which is a lubricating oil passage. From this fourth passage 12, a fifth passage having an orifice 27, a check valve 28, and two orifices is connected.
From the passage 15 to the third speed section 14 of the transmission control device 13 and the orifice 30. A sixth valve having a check valve 31 and an orifice 32
It flows from the passage 17 to the overdrive section 16 and from the seventh passage having the orifice 33 to the differential gear 1.
Flows to 8th class.

Next, regarding the supply of oil to the third gear section 14 and the A-patribe section 16 when the automobile shifts gears,
This will be explained using the ECT computer function flowchart shown in FIG.

When the throttle opening θ is a certain value θ1 and the vehicle speed V becomes greater than VO, the Sl-1 viewer 20 determines that the gear is shifted Igi-! Ill.

S2 Computer 20 cleans its timer and sets T=0.

S3: Determine whether or not the solenoid 21 is turned on.

To make this determination, it is necessary to flow oil from the first passage 6 to the tenth passage 26 based on the discharge amount of the oil pump 1 (engine speed Ne) and the throttle opening θ to find a region where no problems will occur in other parts. Preset. In addition,
If the discharge amount of the oil pump 1 is large, S3 is not necessary.

S4 When the solenoid 21 is turned on, the check valve 22
is opened, and its input port 22a and exit port 22d
The oil at the line pressure PL flows from the eighth passage 23 to the tenth passage 26, and from this tenth passage 26 to the fifth passage 26.
It flows into the passage 15 and the sixth passage 17. Here, if the oil pressure in the fourth passage 12 is P LuB, this p Lu
B is equal to or smaller than the line pressure PL (P Lu
B≦PL), therefore, the check valves 28 and 31 are closed, and the line pressure P[ passing through the A refits 29 and 32 is
A large amount of oil flows into the third speed section 14 and the overdrive section 16. In this way, a large amount of oil flows into the multi-disc brake and multi-disc clutch of the third speed section 14, and a large amount of oil flows into the multi-disc brake and multi-disc clutch of the overdrive section 16, causing damage to the discs and plates. It is possible to suppress the rise in surface temperature.

S5 Predetermined time - [0 and Quimaster 1
- Compare with later time T.

When S6T≧TO, the solenoid 21 is turned off and the check valve 22 is activated, so its outlet bow h 22 d
is no longer communicating with the input port 22a, so the flow of oil to the tenth passage 26 is cut off. As a result, 3
Oil is supplied to the speed section 14 and overdrive section 16 from the fourth passage 12, and the normal lubrication state is restored.

The J3, F CT ml computer 20 clears the timer after determining the shift, so if the shift is to be continued, the normal lubrication state is returned to after the final shift is completed and TO. This is to supply hydraulic pressure for a predetermined period of time during gear shifts when lubricating oil is required, in order to minimize the load on the oil pump caused by supplying hydraulic pressure.

As described above, when the oil at the line pressure P1 flows from the 10th passage 26 to the 3rd speed section 14 and the A-patrive section 16 during gear shifting, the oil flows to the 3rd speed section 14 and the A section 14-pattribe section 16. This can be done by adjusting the size of the A-refice 27 and orifice 29 in the 3rd speed section 14, and by adjusting the size of the orifice 30 and orifice 32 in the overdrive section 16, to improve the oil flow in the normal lubrication state. The desired amount can be adjusted without changing the amount.

FIG. 4 shows a second embodiment of the present invention, in which the tenth passage 26 connected to the outlet boat 22d of the check valve 22 of the first embodiment is removed, and the input port 22a of the check valve 22 has a first The passage 6 and the fourth passage 12 connected to the third passage 9 are connected. And exit port 22
A passage 34 connected to d and branched from the fourth passage 12,
A branch passage 35 having an A refit 37 is connected by a connecting passage 36, and this connecting passage 36 is connected to the third speed section 14 and the overdrive section 16, respectively.

In this embodiment, when the vehicle is normally running, the ECT computer 20 turns off the solenoid 21 as in the first embodiment, so the check valve 22 is closed.
The input port 22a and the exit boat 22d are not in communication. Therefore, the oil of the lubricating oil pressure LLII8 is transferred to the branch passage 35.
From there, it is supplied to the third speed section 14 and overdrive section 16 via an orifice 37 . When changing gears of the vehicle, the check valve 22 is placed in between as in the first embodiment, and the driver capo h 22a and the outlet boat 22d are communicated with each other, so that the oil in the fourth passage 12 is also transferred from the passage 34 to the third gear. The oil will be sent to the overdrive section 14 and the overdrive section 16, and a large amount of oil will be supplied.

As is clear from the above description of the effects of the invention, when the automatic type is shifted, the engine detects the shift and supplies the line 11 to the shift control device of the hydraulic automatic transmission. Since the valve is activated, a larger amount of oil is supplied to the multi-disc clutch and brake installed in the shift control WJ device than during normal driving, and the disc of the multi-disc clutch and brake that operates when shifting gears is rapidly activated. Cold ti+'!
4. Avoid excessive surface temperature of the disk or plate.
can be suppressed.

Therefore, automatic transmissions can respond to higher engine outputs and higher rotational speeds and wider gear ratios with sufficient durability. Further, the supply of oil to the speed change control device during speed change is stopped after a predetermined time has elapsed in order to reduce the pump load based on a command from the computer. In addition, it is possible to appropriately prevent torque loss due to oil rubbing due to disks and plates and oil agitation in various parts.

[Brief explanation of drawings]

1 to 4 show embodiments of the present invention.
The figure is an enlarged view of part A in Figure 1, Figure 3 is a functional flowchart of the computer in Figure 1, Figure 4 is a diagram showing the lubricating oil supply route of the second embodiment, and Figure 5 is an automatic transmission. FIG. 1...Oil pump 4...Primary regulator valve 10...Secondary regulator valve 13...Speed change control [l device 14...3rd speed section 16...Overdrive section 20...ECT computer ( Speed change detection means) 21.
... Solenoid (valve opening/closing means) 22 ... Bueck valve applicant Toyota Motor Corporation agent Patent attorney Oka 1) Hideo Gutai 1 Fig. t (Fig. 2, Fig. 8)

Claims (1)

[Claims] A hydraulic control device for an automatic transmission including a fluid coupling and a gear transmission mechanism with a plurality of frictional engagement devices for obtaining several gear stages, the hydraulic control device including a hydraulic source and a pressure regulated A hydraulic control valve that generates line hydraulic pressure, a shift judgment section that judges the shift of the automatic transmission, and a solenoid valve that is turned on and off based on the judgment of the shift judgment section are switched by hydraulic pressure supplied to provide lubrication. A hydraulic control device comprising a switching valve that selectively supplies oil to the frictional engagement device.