JPS59187164A - Line pressure control device for automatic speed change gear - Google Patents

Abstract

PURPOSE:To prevent shock of speed change upon lockup by a method wherein a hydraulic pressure for operating groups of clutch and brake of the speed change gear as well as a lockup mechanism is reduced upon operation and releasing of the lockup mechanism. CONSTITUTION:When a lockup operating signal is outputted and a lockup solenoid 29 is operated to close a port 13d, pressure regulating oil, acting on a line 13d, is delivered to inlet lines 30a, 30b through an orifice 13b. The pressure regulating oil, supplied from the inlet line 32a to a one-way orifice 32, enters into an exit line 32b as it is through a check valve 32c and acts on the port 17c of a pressure modifier valve 17. According to this action, the pressure modifier valve 17 operates suddenly together with the operation of a lockup solenoid 19 to reduce an oil pressure for the groups of clutch and brake and a lockup valve 30 is operated under a condition delayed from the oil pressure reducing operation.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention provides line pressure control for controlling the supply of hydraulic pressure to the torque converter lock-up mechanism of an automatic transmission for automobiles and the clutch/brake group for setting each speed stage. It is related to the device. More specifically, the present invention relates to a line pressure control device for an automatic transmission having a cutback mechanism that lowers the hydraulic pressure supplied to a clutch/brake group.

(Prior Art) Automatic transmissions for automobiles have been known in various types and have been adopted in many automobiles. The automatic transmission is based on a plurality of planetary gear sets, a plurality of friction engagement means for switching the power transmission path of the planetary gear sets to obtain a plurality of shift positions, and a predetermined relationship between vehicle speed and engine load. Many automatic transmissions are comprised of a hydraulic circuit that selectively fully supplies and discharges hydraulic pressure to the friction engagement means, and many inventions have been proposed regarding this type of automatic transmission.For example, Japanese Patent Application Laid-Open No. 56-24255 The system includes a torque converter, a lock amplifier clutch that bypasses the Konotorque Konohata and connects directly to the engine, a plurality of planetary gear sets, and a friction engagement means that switches all of the power transmission paths of this planetary gear set.
An automatic transmission is disclosed that includes this frictional engagement means and a hydraulic circuit that controls supply and discharge of hydraulic pressure to the lock amplifier clutch. In this invention, it is possible to fully control the lock-up clutch for each gear stage to improve fuel efficiency, and when the lock-up clutch is disengaged, the friction engagement means is prevented from slipping due to the torque amplified by the torque converter. The system prevents this by increasing the working oil pressure, and conversely lowers the oil pressure during gear shifting to cause the frictional engagement means to slip, completely reducing the gear shifting shock.According to this proposal, the gear shifting shock can be reduced. In a transmission having a torque converter equipped with a lock amplifier clutch as described above, it is desired to reduce the shock at the time of lock-up/drunk or release because it remains the same.

In particular, since the entire lock amplifier is often used for all purposes such as improving fuel efficiency, it is desirable to minimize the shock during lock-up.

(Object of the Invention) In view of the above circumstances, the present invention provides full hydraulic control of the clutch/brake group of the transmission and the lock-up mechanism when the lock-up mechanism is activated and released, thereby reducing the shock during lock-up. (Structure of the Invention) The line pressure control device for an automatic transmission of the present invention provides a line pressure control device for a speed gear setting clutch/brake group. A cut-back mechanism for reducing supply oil pressure, a lock amplifier mechanism for performing lock-up, and lock amplifier delay means and cutback delay means for controlling the operation of the cut bank mechanism and lock-up mechanism at the time of lock-up. When the lock-up activation signal is issued, the lock-up delay means activates the cut-back mechanism 2, and then the lock-up mechanism is fully activated, and when the lock-up release signal is issued, the Cantobeck delay means activates the lock-up mechanism. After the cutback mechanism is released, the cutback mechanism is completely released.

(Effect of the invention) According to the present invention, when the lockup is activated, the first thing that happens is
After the back mechanism is activated and the hydraulic pressure supplied to the clutch/brake group is completely lowered, the lock amplifier mechanism is activated, and when the lockup is released, the lock amplifier mechanism is first deactivated, and then the cutback mechanism is fully deactivated. Since the hydraulic pressure supplied to the brake group is returned to its original level (increased), when lock-up is activated or released, the hydraulic pressure of the clutch and brake group decreases, reducing the capacity of the clutch and brake gear and preventing them from slipping. The clutch or brake slips and absorbs the large transmitted torque that leads to the 7-stroke when the lock-up is activated or released, reducing the 7-stroke. Furthermore, during lock-up operation, the cut-back mechanism lowers the hydraulic pressure to reduce hydraulic loss, thereby improving fuel efficiency. There is also the advantage that it can be done by switching using a switch, etc.

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

The figures are a sectional view of a transmission portion and a hydraulic control circuit diagram showing an embodiment of an automatic transmission having a line pressure suppressing device according to the present invention.

The automatic transmission AT includes a torque converter 3, a multi-stage gear transmission mechanism 40, and an overdrive planetary gear transmission mechanism 50 disposed between the torque converter 3 and the multi-stage gear transmission mechanism 40. .

The torque converter 3 has an impeller 3a coupled to the engine output shaft 1, a turbine 3b disposed opposite to the impeller 3a, and a stator 3ci disposed between the impeller 3a and the turbine 3b. is connected to the transmission input shaft 4. A lock-up clutch 2 is connected between the converter 1 input shaft gain and the impeller 3a.
is provided. This lock-up clutch 2 is constantly pushed in the engagement direction by the hydraulic pressure circulating within the torque converter 3, and is engaged when there is no hydraulic pressure supplied from the line 30d to directly control the engine output for gear change. It is transmitted to the machine input shaft, and when hydraulic pressure is supplied from line 30d at approximately the same pressure as the internal pressure of torque converter 3, it is released and the engine output is transmitted to the torque converter. (Hydraulic pressure supply to line 30d will be described later.) Therefore, the engine output is transferred directly to the overdrive planetary wheel mechanism when lock-up clutch 2 is engaged, or via the torque converter 3 when lock-up clutch 2 is released. 50 and the multi-stage vehicle transmission mechanism 40,
The clutch/brake group switches the power transmission path of the planetary gear set to change speed. Clutch for this shift
The brake group includes a front clutch 41, a rear clutch 42,
Consisting of a front brake 44, a rear brake 43, a one-way clutch 45, an overdrive brake 51, and a direct clutch 52, the front clutch 41 and the rear clutch 4
2. The rear brake 43 and the direct coupling clutch 52 are operated by hydraulic pressure selectively supplied based on the hydraulic circuit shown in the lower part of the figure, and the one-way clutch 45 regulates its rotation direction in all directions, and the front brake 44 and the overdrive Drive brake 51 is actuated by actuators 26 and 25.

Note that the γ actuators 26 and 25 are operated by hydraulic pressure selectively supplied based on the hydraulic circuit shown in the figure. Therefore, the setting of each speed stage can be done by appropriately controlling the supply of hydraulic pressure to the clutch/brake group or actuator 25, 26. This supply of hydraulic pressure is shown in the lower part of the figure. This is done based on the hydraulic circuit diagram. First, the oil discharged from the hydraulic pump 11 driven by the engine etc. is adjusted by the grease regulator V-ta valve 12 so that the appropriate pressure is supplied to the clutch/brake group. As pressure increases, excess oil flows to line 12.
b + 30 a, 30 b f to the torque converter 3 (J' The internal pressure of the torque converter 3 and the oil pressure of the inlet line 30b are regulated to a constant pressure. On the other hand, the oil pressure regulated by the Greso Shangyurator valve 12 is transferred to the lines 17a, 17b and the plenum oil pressure. Fire Valve 17k Via Gretsusha Regyu L
/- It is supplied to the upper end 12a of the valve valve 12 in the figure, and can also be supplied to the manual valve 13. Manual valve ■3 is the driver's control lever (change L/
The hydraulic pressure is applied to each valve according to the hydraulic circuit shown in the figure, depending on the position of the manual valve (P, R, N, D, 2.1), which is linked with the change lever position and is determined according to the position of the change lever. supply In addition, pressure V regulator valve 1
The oil whose pressure is regulated by 2 is supplied to the OD release valve 23, actuator 25.
2 is also supplied.

In this way, the hydraulic pressure id supplied according to this circuit, the first
The cabana valve 27 and the second cabana valve 28 are operated based on the vehicle speed, the solenoid down/down valve 22 is operated by the down shift lens 61, and the engine intake manifold negative pressure is operated (i.e.,
operation of vacuum throttle valve] 9 by diaphragm vacuum 6o, which operates according to the engine load;
1-2 due to the operation of the overtriple noid 24, etc.
Shift valve 15.2-3 syn!・Valve 16, presso/yamodifier valve (also called cutback valve)] 7, throttle backup valve 20.3-4
The shift valve 18.3-4 timing valve 23, second lock valve 14, and actuator 25.26 operate as appropriate to select the operation of the clutch/brake group described above according to the position of the manual valve 13, vehicle speed, and load. Automatic gear shifting is performed according to the timing. Table 1 shows the relationship between the operation of the clutch/brake group, the position of the manual valve 13, and the speed stage. (In the table, the clutch or brake marked with a circle indicates that it is operating, and the manual valve 13 is 'D', '2''.

' When in any position of "1", the pressure regulator valve 12 is connected via this manual valve 13k.
The oil pressure regulated by Life], 3a can be completely supplied to line 13a, but line 13c is branched from line 13a via orifice 13bi, and this line], 3c is the first one-way that forms a lock-ag slow-acting mechanism. Orifice chair 3
1 and the second artificial line 32a to the second one-way orifice 32 forming the cutback delay mechanism, and the communication hole to the D/ON side is opened and closed by the lock-up operation solenoid 29. port 1
, 3 d are also connected.

The first one-way orifice 31 is a check valve 31c
and an orifice 31d, the first output line 3
], The first outlet line 311 is connected to the opposite side from a.The check valve 31c is connected to the first outlet line 31b.
The flow from the first input line 31a to the first output line 31b is allowed to pass through, but the flow from the first input line 31a to the first output line 31b is not allowed to pass through.
Since the oil flowing from a to the first outlet line 3] and b passes only through the orifice 3]d, the flow rate is restricted. moreover,
1st output line 31b communicates with port 30It at the lower end in the figure of the lock-up pulp 30, and the pressure regulating oil sent to the 1st output line 3],b is connected to this port) 301+
When acting on the lock-up valve 30 spool 30g
1 Push up against the 30f force of the spring. Therefore, when the hydraulic pressure is not acting on the above port 30h, the syspool 30g is pushed downward by the currant nog 30f, and the communication between the line 30c and the life 30d is cut off, and the line 30d is on the drain side. The oil pressure of line 30d becomes zero. When the oil pressure in the line 30d becomes zero, the lock-up clutch 2 is engaged as described above and enters the lock-up operating state. That is,
The lock asog mechanism can be activated by increasing the oil pressure of the first output line 3Ji). Conversely, when the spool 30g is lowered, the line 30g is lowered.
A hydraulic pressure equal to the internal pressure of the torque converter acts on the line 30d from c to release the lock-up clutch 2.

The second one-way orifice 32 includes a check valve 32c and an orifice 32d, and the flow from the second person's first line 32a to the second outlet line 32b is passed through the check valve 32c, and from the second person's first outlet line 32b to the second outlet line 32b. Flow into line 32a is restricted only through orifice 32d.

The second output line 32b is the boat 17 at the right end of the diagram of the pretsunoyamo diffuser valve (cutback valve) 17.
c, and communicates with the port 17 via the second output line 32bi.
When hydraulic pressure acts on C, the spool 17d is pushed to the left against the biasing force of the spring 17e. Spool 1.7
When d is pressed, the pre-yamo fire valve 17
Lines 17a and 17b, which were previously cut, are now connected. Therefore, oil pressure is supplied to the upper end 12a of the pre-regulator valve 120, and the oil pressure at the upper end 12a increases. The hydraulic pressure acting on the upper end 12a, together with the hydraulic pressure of the other port 12b and the biasing force of the spring 12C, regulates the pressure of the pre-regulator valve, and when the hydraulic pressure of the upper end 12a increases, the hydraulic load on the port 121) decreases. , the oil pressure of the boat 12b, i.e., puV
The pressure regulation of the Tsusha regulator valve 12 also decreases. That is, by applying hydraulic pressure to the second output line 32b and moving the spool 17df of the pressure modifier valve 17, it is possible to lower the hydraulic pressure supplied to the clutch/brake group (perform cutback).

On the other hand, the oil pressure supplied to the first one-way orifice 31 and the second one-way orifice 32 is determined by the oil pressure of the line 13c, and the oil pressure of this life 13c is controlled by the lock apple noid 29. It is decided. That is, when the lock-up solenoid 29 is fully activated and the boat 13di is closed when the lock-up activation signal is issued, the pressure regulating oil by the Glennonya regulator valve 12 acting on the line 13d is passed through the orifices 1, 3 +) f. It is transmitted to line 1-3 c,
After that, the first exit line 30a and the second population line 30
The pressure regulating oil supplied from a to the first one-way orifice 3J is the orifice 31.
d only passes through, so the oil pressure of the lock-up valve boat 30h via the first output line rises after a predetermined time delay. On the other hand, the pressure regulating oil supplied from the second population line 32a to the second one-way orifice 32 passes through the check valve 320 and continues to the second outlet line 32.
pressure modifier valve] 7 boat], 7 acts on c. Therefore, the pressure modifier valve 17 has a lock-up solenoid 19.
It operates rapidly with the operation of cant bank, that is, lowers the oil pressure to the clutch and brake group.
Lock-up valve 30 (1-1, operates later than the above operation.

Next, when a lock amplifier release signal is issued from the lock-up operating state and the port 13d is opened by the lock-up solenoid 29, the oil in the line 13c is released from the port].
Ejected from 3d. Note that oil from line 13a is restricted by orifice 13b, so oil from line 13a is restricted by orifice 13b.
The oil pressure at c decreases. For this reason, the first population Rai/31a
The oil pressure in the second population line 32a also decreases, and the oil in the first outlet lines 3] and b flows out through the first one-way orifice, and the oil in the second outlet line 321] flows out through the first one-way orifice.
It flows out through the entire one-way orifice.

In this case, the oil in the first outlet line 311 rapidly flows out through the check valve 31ci and
While the oil pressure of 30 h is rapidly lowered, the oil in the second outlet line 321) is
Since the oil flows out only through d, the oil level at port 17c of pressure modifier valve 7 gradually decreases. Therefore, when releasing the lock-up, the lock-up valve 3
0 is activated rapidly together with the activation of the lock-up solenoid 29, and cant back is activated later than this activation.

As described above, when the lockup is activated, the entire lockup is performed after canting back, and when the lockup is released, the lockup is performed and then the cutback is performed.

In addition, in the above embodiments, all examples were shown in which the one-way orifice was gold-layered, but two electrically operated valves were provided in place of the first and second one-way orifices, and one valve was activated when the lock-up was activated and when the lock-up was released. The same effect as above can be obtained by operating with a delay. In addition, if it is done electrically, it is simple, just replacing it with a one-way orifice fully electrically operated valve, so detailed explanation will be omitted here.

[Brief explanation of the drawing]

The figures are a sectional view and a hydraulic control circuit diagram of a transmission portion of an automatic transmission having a line pressure control device according to the present invention. ■・・・－・・・・Engine output shaft 2・・・・・・
...Lock-up clutch 3...Torque converter 1]...Hydraulic pump 12... -Brochure regulator valve 13...Manual valve 17...Pressure modifier valve 29...
... Lock-up solenoid 30 ... Lock-up valve 31 ... First one-way orifice 32 ... Second one-way orifice 40 ...
...Multi-stage gear transmission mechanism 50... Planetary gear mechanism AT for overdrive...
・・Invention title: automatic transmission (self-initiated) procedure ne pressure document May 30, 1982, patent application No. 58-5434 ON 2, name of invention automatic transmission (spontaneous transmission) Related: Patent applicant 4, agent 5-2-1 Roppongi, Minato-ku, Tokyo, 5, no date of amendment order 6, number of inventions increased due to amendment: none 7
, Correction target drawing

Claims (1)

[Claims] A cutback mechanism that lowers the hydraulic pressure supplied to the clutch/brake group that determines the speed stage of an automatic transmission, a lockup mechanism that locks up a torque converter with a lockup clutch, and a cantback mechanism that responds to a lock amplifier activation signal. and lock-up delay means for operating the lock-up mechanism later than the operation of the cut-back mechanism; and lock-up delay means for releasing the operation of the lock-up mechanism in response to a lock-up release signal and delaying the cut-back operation than the release of the lock-up mechanism. A line pressure control device for an automatic transmission comprising cutback movement means for deactivating the mechanism.