KR0125887B1 - Auto t/m brake control system - Google Patents

Abstract

Disclosed is a system to control oil pressure of an engine brake in a 3 stage automatic gear. The system comprises the third pipe(12), the seventh pipe(32), a solenoid valve(43), an electronic control unit(42) and an operating switch(44). The third pipe(12) is connected to the second shift valve(14) so that 2 and 3 stage gearing is activated in 3 stage mode to prevent a mis-braking. The pressure of a modulator according to the oil pressure from the third pipe(12) is induced to the tenth port(34) by the seventh pipe(32). The solenoid valve(43) controls flowing in the eighth pipe(41) between the third pipe(12) and the seventh pipe(32). When a mis-braking occurs, the electronic control unit(42) opens the solenoid valve(43) for 2 stage gearing. Thereby, the low stage gearing can be automatically performed in the mis-braking, so that a safe driving is improved.

Description

Engine brake hydraulic control system of three-speed automatic transmission

1 is an enlarged view of the operation of the engine brake hydraulic control unit according to the present invention.

2 is a circuit diagram of a hydraulic control apparatus according to the prior art.

* Explanation of symbols in the main part of the drawing *

11: governor valve, 12: third pipe,

14: second shift valve, 25: seventh port,

31: throttle valve, 32: seventh pipe,

41: eighth pipe, 42: electronic control device,

43: solenoid valve, 44: operation switch.

[Field of Invention]

The present invention relates to an engine brake hydraulic control system of a three-speed automatic transmission, and more particularly, to an engine brake hydraulic control system of a three-speed automatic transmission in which a low speed shift is automatically performed when an engine brake fails. It is about.

[Prior art]

In general, an automatic transmission is a transmission in which a fluid torque converter and a planetary gear device are commonly combined and a hydraulic control system is used to automatically shift according to operating conditions and engine load. In addition, the automatic transmission has a torque converter and a multistage transmission gear mechanism connected to the torque converter, and hydraulically actuated friction for selecting one of the gear stages of the transmission gear mechanism according to the operating state of the vehicle. Contains an element.

The structure of the automatic transmission varies depending on the driving method of the vehicle (front wheel drive or rear wheel drive), but the main parts are composed of a torque converter, an oil pump, a throttle valve, a governor valve, a manual valve, a kick down switch, and the like.

The torque converter, which is one of the above components, is located between an impeller fixed to the crankshaft of the engine and rotating together, a turbine coupled to the input shaft of the transmission by a spline and disposed to face the impeller, and the impeller and the turbine. It includes a stator that changes the flow of oil.

The planetary gear set is of type L, which is composed of a forward sun gear, a reverse sun gear, a short pinion, a long pinion, and a carrier and an annular gear supporting two pinion shafts.

The reverse sun gear is connected to the front clutch retainer by means of a kick-down drum, and the battery sun gear is connected to the rear clutch hub.

The carrier is integrated with the hub of the low reverse brake and the outer race of the one-way clutch. The 4A / T carrier is connected to the end clutch by an end clutch via the end clutch shaft.

The annular gear is connected to the output flange and transmits a driving force to the transfer drive gear mounted to the output flange. A parking sprag gear is installed on the outer periphery of the annular gear.

The oil pump has a type installed only at the transmission input side and a type installed at both the transmission input side and the output side. Accordingly, the pump installed at the input side is driven by a pump drive gear connected to the converter at the same time as the engine rotates to supply oil to the torque converter and to maintain the converter hydraulic pressure (3-7 bar).

It also lubricates the planetary gear units and supplies the hydraulic fluid at line pressure to the control system. The pressure generated by the oil pump is regulated primarily by the regulator valve according to each condition. This pressure is called the line pressure.

The multi-plate clutch and the brake (band) are controlled by this line pressure and other control pressures, and the pump installed on the output side supplies hydraulic pressure to the transmission at a certain speed or more.

The throttle valve, which controls the modulator pressure, is connected to the vacuum actuator by a linkage. The line pressure generated by the oil pump is applied to the throttle valve. The line pressure acting on the throttle valve is converted into the modulator pressure according to the change in the degree of vacuum of the intake manifold.

That is, the modulator pressure is derived from the throttle valve as the line pressure. The modulator pressure corresponds to the governor pressure with the shift valve piston in between.

In addition, the governor is installed on the transmission output shaft to change the governor pressure according to the traveling speed of the vehicle, and this pressure increases as the traveling speed increases. This pressure acts on the shift valve and corresponds to the modulator pressure with the piston in between.

The piston diameter of the shift valve is larger on the side where the governor pressure acts than on the side where the modulator pressure acts. When this constant speed is reached, the governor pressure actuates the shift valve piston in response to the modulator pressure and the tension of the spool so that the gearshift is sequentially shifted to 1-2, 2-3 (or 3-4).

Therefore, when the driving speed is lowered, the governor pressure is lowered again, thereby automatically shifting down to the lower stage gradually.

And the manual valve in the valve body is the operator to operate the selector lever to determine its position. This means that the main operating pressure generated by the oil pump is applied to the multi-plate clutch and the brake (band) circuit corresponding to the shift stage via the manual valve.

The position of the piston contained in the manual valve is determined by the operator operating the selection lever to select the desired position from the selection position. Depending on the selected position, the modulator pressure acting on the shift valve is affected and acts to block or connect the control circuit according to the shift means.

In the kickdown switch, when the accelerator pedal is pressed, the kickdown switch is operated to rapidly increase the modulator pressure. When the kick-down switch is activated, the gear is shifted to a lower stage than the current stage within a certain speed range.

As described above, FIG. 2 shows the D range third speed in the shift state of the conventional automatic transmission. This is because when the driver shifts the selection lever position from the 2nd stage to the 3rd stage of the D range, the hydraulic pressure of the oil pump 3 is transferred to the ring gear 1 through the carrier 2 so that the hydraulic pressure of the oil pump 3 is increased in the first conduit 4. It is introduced into the first port 6 of the manual valve (5) through.

In addition, the hydraulic pressure flowing into the manual valve 5 through the first port 6 is carried out through the cylinder 10 and the governor valve in which the brake band 9 is installed along the second conduit 8 connected to the second port 7. Line pressure is formed in (11).

Since the governor valve 11 is in a state in which power is transmitted and rotates at a second speed, the third conduit 12 connected to the governor valve 11 is provided to the first and second shift valves 13 and 14. The hydraulic pressure is pressurized. In particular, the hydraulic pressure through the sixth port 15 of the first shift valve 13 moves the first valve spool 16.

Accordingly, the hydraulic pressure that overcomes the elastic force of the first elastic member 17 embedded in the first shift valve 13 presses the first shift valve 13 so that the first valve spool 16 moves so that the third port ( 18) and the fourth port 19, the hydraulic pressure is pressed to the clutch.

The first shift valve 13 is connected to the second shift valve 14, and the fourth port 19 is connected to the fifth port 21 by the fourth pipe 20, and the hydraulic pressure is the fourth. The third stage clutch 23 is clutched through the fifth conduit 22 connected to the conduit 20.

When the accelerator pedal 24 is pressed in the clutching state, the governor valve 11 rotates at a high speed to achieve a complete opening.

Accordingly, the line pressure formed in the second conduit 8 by the governor valve 11 is transmitted to the second shift valve 14 through the seventh port 25 with a strong line pressure as it is through the third conduit 12. When the second valve spool 26 is moved to overcome the elastic force of the second elastic member 27.

When the second valve spool 26 is moved and the fifth port 21 and the eighth port 28 communicate with each other, the hydraulic pressure passes through the sixth pipe 29 connected to the eighth port 28. The clutch 30 is clutched to allow three speeds to travel in a direct connection state.

At this time, when the accelerator pedal 24 is pressed, the throttle valve 31 is opened by the negative pressure of the engine, and the oil flows into the seventh pipe 32 through the first pipe 4, and the first and second shift valves 13 are opened. Through the ninth and tenth ports 33 and 34 of (14), the discharge or suction is controlled.

Therefore, the brake band 9 of the secondary sun gear 35 is loosened, and since the rotation speeds of the primary sun gear 36 and the ring gear 1 are the same, the planetary gear sandwiched in the middle cannot rotate, and thus the planetary gear is rotated. The whole gear is massed and rotated.

In this case, the rotation speed of the transmission input shaft is the same as the rotation speed of the transmission output shaft and the rotation directions are the same (ie, directly connected).

If the user fails to try to brake by stepping on the brake pedal in the three-stage driving state, the engine brake may not be used and the driver may easily be embarrassed while driving, causing injury or damage to the vehicle.

[Summary of invention]

It is an object of the present invention to provide an engine brake hydraulic control system of a three-speed automatic transmission in which a low speed is automatically shifted when the brake fails of an automatic transmission vehicle to achieve an engine brake.

The present invention for realizing this is connected to a shift valve to make a 2, 3 shift in order to prevent the braking failure during the third speed driving in a vehicle equipped with a three-speed automatic transmission, the hydraulic pressure flowing into the seventh port through the governor valve The third pipe line, and the seventh pipe line allowing the modulator pressure according to the opening degree of the throttle valve to flow into the tenth port according to the increase or decrease of the hydraulic pressure flowing through the third pipe line, and the third pipe line and the seventh pipe line A solenoid valve for direct connection to the eighth pipe connected directly, an electronic controller for controlling the solenoid valve to open in case of braking failure, and a two-speed shift, and a power supply for braking failure by the electronic controller. It features an engine brake hydraulic control system of a three-speed automatic transmission that includes an actuating switch that the driver turns ON.

[Example]

Hereinafter, with reference to the accompanying drawings a preferred embodiment of the present invention will be described in more detail.

1 is an enlarged view of the operation of the engine brake hydraulic control unit according to the present invention, the same reference numerals for the same parts as in the prior art of FIG. Reference numeral 40 denotes the engine brake of the automatic transmission.

The engine brake device 40 installed in the three-speed automatic transmission is installed to prevent a failure of braking during three-speed driving in a vehicle equipped with the automatic transmission.

In the engine brake device 40, the hydraulic pressure through the governor valve 11 is transferred to the second shift valve 14 to the seventh port 25 to the second shift valve 14 so that the three speed shift is performed. Inflow is being made.

The modulator pressure according to the opening degree of the throttle valve 31 is introduced into the tenth port 34 through the seventh conduit 32 as the hydraulic pressure flowing through the third conduit 12 is increased or decreased.

An eighth pipe 41 is formed to directly connect the third pipe 12 and the seventh pipe 32. The solenoid under the control of the electronic control device 42 in the middle of the eighth pipe 41 is formed. The valve 43 is provided.

The solenoid valve 43 is operated by the electronic control device 42 to which power is applied when the operation switch 44 is turned on when the driver determines that braking has failed.

When the solenoid valve 43 is opened, the hydraulic pressure applied to the seventh port 25 and the tenth port 34 of the second shift valve 14 becomes equal.

Accordingly, the hydraulic pressure flowing into the sixth conduit 29 through the eighth port 28 of the second shift valve 14 is reduced in pressure so that the two-stage clutch 30 is interrupted and the two-speed shift is made. The brake operation is performed.

The operation of the present invention made as described above is that when the vehicle equipped with the automatic transmission fails braking at three speeds, the driver presses the engine brake operation switch 44 to turn on the power so that the power supply is controlled by the electronic controller 42. To be applied to.

The electronic control device 42 allows the power supply to the solenoid valve 43 so that the seventh port 25 of the second shift valve 14 and the third conduit 12 connected to the tenth port 34. And the eighth conduit 41 which directly connects the seventh conduit 32 to open so that the strong hydraulic pressure of the third conduit 12 and the line pressure of the seventh conduit 32 collide with each other to have an equal hydraulic pressure. The valve spool 26 is pushed together with the elastic force of the elastic member 27 toward the seventh port 25 to block the hydraulic pressure exiting to the eighth port 28.

Accordingly, since the eighth port 28 of the second shift valve 14 is blocked, the hydraulic pressure flowing into the sixth conduit 29 is cut off so that the second stage clutch 30 is interrupted and the third speed is lowered to the second speed. The result is engine brake actuation.

This invention is an invention in which the engine brake can be used safely even when the brake pedal is failed by stepping on the brake pedal in the three-stage driving state, so that not only safety of the driver but also human life and property preservation are achieved.

Claims (1)

In a vehicle equipped with a three-speed automatic transmission, the seventh port is connected to the second shift valve 14 to allow two- and three-speed shifting to prevent braking failure during three-speed driving. The modulator pressure according to the opening degree of the throttle valve 31 is applied to the tenth port 34 as the third pipe line 12 flowing into the 25 and the hydraulic pressure flowing through the third pipe line 12 increases or decreases. The solenoid valve 43 which communicates with the 7th pipe 32 which made it flow in, the 8th pipe 41 which directly connected the said 3rd pipe 12, and the 7th pipe 32, and this solenoid valve 43 ) Is controlled to open when braking fails, the electronic control device 42 to make a two-speed shift, and the operation switch for the driver to turn on (ON) so that power is applied when the braking failure by the electronic control device 42 Engine brake hydraulic control of the three-speed automatic transmission characterized in that it comprises a (44) System.