JPS63186057A - Control device of hydraulic type transmission for vehicle - Google Patents

Abstract

PURPOSE:To prevent the burning damage of a hydraulic clutch and the like, by restricting a shift valve at the converting position regardless of the control by an electronic control circuit, when a servo valve is at the back position, in the converting condition of a manual valve to the automatic transmission position. CONSTITUTION:When a manual valve 9 is at the R position, the first oil way L1 is connected to the 16th oil way L16 which is linked to the first shift valve 101, and since the first shift valve 101 is being connected to the second shift position, the 16th oil way L16 is connected to the 17th oil way L17 which is linked to a servo valve 11. And the backward transmission system is established by feeding oil to the 4th hydraulic clutch C4 and the connection of a solenoid gear 6 to the backward position. Furthermore, at the R position, when the oil is fed to the servo valve 11 and the vehicle is running at a specific speed or more, the backward transmission system is prohibited from establishment by converting the first shift valve 101 to the first speed position to prevent the linking of oil ways 16 and 17.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention has a plurality of transmission systems for forward movement that are each established by engagement of each hydraulic clutch, and a hydraulic clutch that is shared by the transmission system of the highest forward speed. a selector gear that includes a one-way clutch that allows over-rotation on the output side in the transmission system of the lowest forward speed, and selectively establishes the transmission system of the highest speed and the reverse transmission system. The present invention relates to a control device for a hydraulically actuated vehicle transmission equipped with a vehicle.

(Prior Art) Conventionally, as shown in Japanese Patent Application Laid-Open No. 61-84450, this type of device has a hydraulic circuit that controls a hydraulic clutch and a selector gear, which can be freely switched between an automatic shift position and a reverse position. A manual valve, multiple shift valves that selectively supply oil to each hydraulic clutch in the forward transmission system except for the lowest speed transmission system, and a servo valve for forward/reverse switching that connects the selector gear are provided. At the automatic shift position of the valve, the hydraulic clutch of the transmission system in the lowest gear is constantly supplied with oil from the hydraulic source, and these shift valves are controlled by the throttle pressure according to the engine throttle opening and the governor pressure according to the vehicle speed. Automatically shifts gears from the lowest gear to the highest gear depending on the driving condition, and when the manual valve is in the reverse position, the servo valve is hydraulically pushed to the reverse position where the selector gear selects the reverse transmission system. It is also known that a hydraulic clutch of a transmission system at the highest speed is supplied with oil through the servo valve to establish a reverse transmission system.

The reason why the hydraulic clutch is shared between the highest gear transmission system and the reverse transmission system is to reduce the size of the transmission and to prevent the transmission system from moving backward when traveling forward, as known from Japanese Patent Application Laid-Open No. 57-190148. This is to prevent noise and power loss by keeping the idling speed of the transmission gears low.

(Problem to be Solved by the Invention) In the above system, the shift valve is configured to be hydraulically switched using throttle pressure and governor pressure, but recently, more detailed shift control and shift characteristics that match the vehicle model have been introduced. Due to ease of modification, an increasing number of vehicles use an electronic control circuit consisting of a microcomputer, etc., input the engine throttle opening signal and vehicle speed signal, and use the electronic control circuit to control the switching of the shift valve. Therefore, even in the prior art described above, it has been considered to control switching of the shift valve using an electronic control circuit.

By the way, in a transmission that uses an electronic control circuit, if an abnormality occurs in the input signal system such as the vehicle speed signal, it will not be able to perform normal gear shift control. Therefore, in such a transmission, a self-diagnosis function for detecting an abnormality in the input signal system is generally added to the electronic control circuit, and the highest gear is established when an abnormality is detected.

Also, when the oil viscosity is high, such as at low temperatures, when the manual valve is switched from the reverse position to the automatic shift position, the return of the servo valve from the reverse position to the forward position is due to the oil drainage resistance from the servo valve. Therefore, by switching the manual valve from the reverse position to the automatic shift position when there is an abnormality in the input signal system, the electronic control circuit will supply oil to the hydraulic clutch of the transmission system in the highest gear. Then, if the servo valve remains in the reverse position due to the delay in returning to the forward position as described above, a reverse transmission system will be established.

Here, when the manual valve is in the automatic shift position, the hydraulic clutch of the lowest gear transmission system is constantly supplied with oil, and the one-way clutch that intervenes in the transmission system does not allow reverse rotation on the output side.
In the above case, both the lowest gear transmission system and the reverse transmission system are established, and excessive force is applied to the hydraulic clutch, causing burnout and premature wear of the clutch disc.

SUMMARY OF THE INVENTION An object of the present invention is to provide a device that can prevent such problems from occurring when the shift valve of the prior art is switched and controlled by an electronic control circuit.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a plurality of forward transmission systems each established by friction of each hydraulic clutch, and a first transmission system serving as the highest forward speed. A one-way clutch that allows over-rotation on the output side intervenes in the second transmission system, which is the lowest forward speed, and the first transmission system and the reverse transmission system share a hydraulic clutch. A hydraulically actuated transmission for a vehicle is provided with a selector gear that selectively establishes the system, and the hydraulic circuit that controls the hydraulic clutch and the selector gear is capable of being freely switched between an automatic shift position and a reverse position. A manual valve, a plurality of shift valves that selectively supply oil to each hydraulic clutch in the forward transmission system except for the second transmission system, and a servo valve for forward/reverse switching that connects the selector gear are provided. At the automatic shift position, the hydraulic clutch of the second transmission system is constantly supplied with oil from the hydraulic source, and these shift valves are controlled by switching #A by an electronic control circuit to perform an automatic shift, and when the manual valve is in the reverse position, the servo A valve is hydraulically pushed to a reverse position where a selector gear selects a reverse transmission system, and a hydraulic clutch of a first transmission system is supplied with oil via the servo valve, wherein the first transmission system An oil chamber is formed in the shift valve that controls the supply and discharge of oil to the hydraulic clutch of the transmission system and the hydraulic clutch of the other third transmission system to the side of the switching device that supplies oil to the third hydraulic clutch. However, when the servo valve is in the reverse position when the manual valve is switched to the automatic shift position, the oil chamber is connected to a hydraulic power source via the manual valve and the servo valve, and the shift valve is connected to the electronic control circuit. It is characterized in that the switch is restricted to the switching position regardless of control by the switch.

(Function) When a failure occurs in the input signal system of the electronic control circuit and the manual valve is switched to the automatic gear shift position, the hydraulic clutch of the first transmission system and the hydraulic clutch of the third transmission system of the highest gear are The shift valve that supplies and drains oil to and from the first transmission system is controlled by an electronic control circuit.

Even if an attempt is made to control the switching to the switching position where oil is supplied to the latch, if the servo valve remains in the reverse position, the oil pressure from the hydraulic source will be input to the oil chamber of the shift valve, and the shift valve will move to the third position. Since the hydraulic clutch of the transmission system is restricted to the switching position where oil is supplied to the hydraulic clutch of the transmission system, and the hydraulic clutch of the first transmission system is not supplied with oil, a reverse transmission system is not established, but a third transmission system is established.

In addition, when the third transmission system is established, the second transmission system of the lowest gear
Even if the hydraulic clutch of the second transmission system is supplied with oil, the one-way clutch that intervenes in the transmission system stops the power transmission through the transmission system, and the hydraulic clutch of the second transmission system or the third transmission system is stopped. No excessive force is applied to the clutch.

After switching the manual valve, when the servo valve returns to the forward position, the oil chamber of the shift valve is disconnected from the oil pressure source, and the shift valve is switched and controlled by the electronic Ill 60 circuit.

(Example) Referring to FIG. 1, (1) shows a transmission that performs four forward speeds and one reverse speed. input shaft (
1a) and an output shaft (1b) that is connected to the drive wheels (4) of the vehicle via a differential gear (5). ) (G4) and a reverse transmission system (Gll), each forward transmission system (G1)
(G2) (G3) (G4) each hydraulic clutch (CIHC2) (C3) (C4) of 1st to 4th speed which is a hydraulic engagement element
intervenes, and each hydraulic clutch (CI) (82) (C3
) (C4), each transmission system (G1) (G2) (
G3) (G4) are selectively established, and the reverse transmission system (GR) shares the 4-speed transmission system (G4) and the 4-speed hydraulic clutch (C4). )
(GIt) is selectively established by the switching operation between the left forward position and the right reverse position in the diagram of the select gear (6) on the output shaft (1b).

In the drawing, (7) is a one-way clutch that intervenes in the first-speed transmission system (G1) and operates to allow over-rotation of the output shaft (1b).

Each of the hydraulic clutches (CIHC2) (C3HC4) is
The oil supply and discharge is controlled by the hydraulic circuit shown in FIG.
"P" for parking and "P" for reversing as shown in Figure 3.
A manual valve (9) that can be freely switched to 6 positions: "R" for neutral, "N" for neutral, rDJ and "S" for automatic shifting, and "2" for holding 2nd gear, and for switching between 1st and 2nd gears. A first shift valve (10+) and a second shift valve (10+) for switching between 2nd and 3rd speeds.
2), a third shift valve (103) for switching between 3rd and 4th speeds, and a servo valve (11) for forward/reverse switching connected to the selector gear (6), and a manual valve (9). At the rDJ position, the first oil passage (11) for refueling is connected to the hydraulic source (8).
) is connected to the second oil passage (L2) connected to the first shift valve (1(h)) via the annular groove (9a) of the valve (9), and the second oil passage (Ll) is connected to the second oil passage (L2) connected to the first shift valve (1(h)). Pressure oil regulated to a constant line pressure by regulator valve a is supplied to line (L2),
Supplying oil to the 1st speed hydraulic clutch (C1) via the 3rd oil passage ([3) branched from the 2nd oil passage ([2)], and
Oil is supplied to the hydraulic clutches (C2) (C3HC4) of the second to fourth speeds through the shift valves (10+), (102), and (103).

The first shift valve (1(h) is switchable between the first gear position on the right and the second gear position on the left, and the second shift valve (102) is in the second gear position on the right and the third gear position on the left. The third shift valve (103) is configured to be able to switch freely between a 3rd speed position on the right side and a 4th speed position on the left side, and a modulator valve 113 connected to the first oil path (Ll). The modulator pressure (constant pressure lower than the line pressure) from the 4th oil passage (L
4) through the orifice (14+).
[5] The oil chamber (1G + a) (102a) at the right end of the first shift valve (10+) and the second shift valve (102)
and the first shift valve (i
t)+) and the right end oil chamber (10ia) of the third shift valve (103), and the electromagnetic type is connected to the fifth oil passage ([5). A normally-closed first atmosphere release valve (151) and an electromagnetic normally-closed second atmosphere release valve (152) are connected to the sixth oil path ([6), and the both air pressure release valves (15+) are connected to each other. ) (Is 2), these shift valves (10+), (102), and (103) are switched in accordance with each gear stage as follows.

That is, in the first gear, the first atmosphere release valve (15+) is opened and the second atmosphere release valve (152) is closed. According to this, the first and second shift valves (10+) (102) are closed. The input of modulator pressure to the rightmost oil chamber (10+a) (102a) is cut off, and the leftmost oil chamber (10+) of the first shift valve (10+) is cut off.
0+ b) and oil 1 (1) on the right end of the third shift valve (103)
The modulator pressure is input to 03a), and the first shift valve (101) shifts to the right side 1 against the right end spring (10+C).
speed position and the second shift valve (102) is at the left end spring (10
The biasing force of 2C) shifts the right 2nd gear position and the 3rd shift valve (1
03) is switched to the left 1st speed position against the left end spring (103C). In this state, the first shift valve (
1 (h), the communication between the second oil passage ([2) on the inflow side and the seventh oil passage (Ll) on the outflow side is cut off, and the first-speed hydraulic clutch ( Only C1) is supplied with oil, and a first-speed transmission system (G1) is established.

In 2nd gear, the first and second atmosphere release valves (15+) (Is
2) are both open, and according to this, the oil chamber (io + b) at the left end of the first shift valve (10+) and the oil chamber (103a) at the right end of the third shift valve (10a) are opened. The input of modulator pressure is also cut off, and the first shift valve (10d) and the third shift valve (103) each have a spring (10IC) (103C).
) is operated to switch between the 2nd speed position on the left and the 3rd speed position on the right, and the second shift valve (102) is held at the 2nd speed position in the same manner as described above. In this state, the second oil passage (L2) is connected to the seventh oil passage (Ll) via the annular groove (10+d) of the first shift valve (101), and the rDJ of the manual valve (9)
The cutout groove (9b) of the valve (9) is connected to the seventh oil passage ([7) at the position
an eighth oil passage (L8) connected via the eighth oil passage (L8);
L8) is connected to the second shift valve (102) in the second gear position.
1(h) connected through the annular groove (IG2d)
The second-speed hydraulic clutch (C2) is supplied with oil via the oil passage (L9), and a second-speed transmission system (G2) is established. in this case,
Power transmission via the first speed transmission system (61) is automatically stopped by the action of the one-way clutch (7).

In the third gear, the first atmosphere release valve (15+) is closed and the second atmosphere release valve (152) is opened;
The oil chamber (1) at the right end of the second shift valve (10+) (102)
Modulator pressure is input to 0Ia) (102a), and the second shift valve (1 (h) is switched to the left 3rd speed position against the spring (102C), and the first shift valve (10+)
and the third shift valve (103) are held at the second and third speed positions, respectively. In this state, the eighth oil passage ([8) is connected to the tenth oil passage (110) connected to the third shift valve (103) via the annular groove (102e) of the second shift valve (1G2), and 3 shift valve (10a) in the 3rd gear position.
3) through the annular groove (103d).
The 3rd speed hydraulic clutch (C3) is supplied with oil through the 11th oil passage (Lll) connected to the 2nd speed hydraulic clutch (C3).
The ninth oil passage ([9) connected to C2) is connected to the second shift valve (
102) through the annular groove (10zd), the first oil drain path is connected to D.
I), 2nd speed is established, oil is drained from the 11-pressure clutch (C2), and a 3rd speed transmission system (G3) is established.

In the 4th gear, the first and second atmosphere release valves (Is +) (Is
2) is closed at j(. According to this, the first shift valve (IO+) and the second shift valve l~valve (10°) are in the 2nd and 3rd gear positions, respectively, as in the 3rd gear. The third shift valve (103) is operated to shift to the left 4th gear position by inputting the modulator pressure to the right end oil chamber (103a).The first shift valve (10+) is oil chamber (1O+a
) (1o + b), the left and right pressing forces due to the modulator pressure are balanced and held at the 2nd speed position by the urging force of the spring (10+cl).In this state, the The No. 10 oil passage (110) is connected to the No. 12 oil passage through the annular groove (103e) of the third shift valve (103).
Connected to the oil line (L12) and rDJ of the manual valve (9)
At this position, oil is supplied to the 4th speed hydraulic clutch (C4) through the 13th oil passage (L13) connected to the 12th oil passage (112) through the notch groove (9C) of the valve (9), and The eleventh oil passage (Lll) connected to the third-speed hydraulic clutch (C3) is connected to the second oil drain passage (LD2) via the annular groove (to3d) of the third shift valve (1G3), and the third-speed hydraulic clutch (C3) is connected to the second oil drain passage (LD2). (C
3) is drained, and the 4-speed transmission system - (G4)
is established.

In addition, when downshifting from 4th gear to 3rd gear, the 12th oil passage (H2
) is connected to the third oil drain path (L[13) through the annular groove (103e) of the third shift valve (10a) in the third gear position, and oil is drained from the fourth gear hydraulic clutch (C4). Also, when downshifting from 3rd gear to 2nd gear, the 10th oil is connected to the 11th oil passage (Lll) via the annular groove (103d) of the 3rd shift valve (10a) located at the 3''A position. Road (1101
The annular groove of the second shift valve (1(h)
102e) to the fourth oil drain passage (LD4) to drain oil from the 3rd gear hydraulic clutch (C3), and when downshifting from 2nd gear to 1st gear, the 2nd gear is connected to the 4th oil drain passage (LD4) as described above. When the seventh oil passage ([1) connected to the second oil passage (L2) is switched to the first gear position of the first shift valve (10+), the seventh oil passage ([1)
) through the annular groove (1o + d) of the oil drain boat (io
+ e), where the seventh oil passage ([7) is connected to 2
Like the gear stage, it is connected to the 2nd speed hydraulic clutch (C2) via the 8th oil passage (1, 8) and the 9th oil passage (L9), so these oil passages (L9) (L8) ( +, 7) via 2
Oil is drained from the quick hydraulic clutch (C2).

As described above, when the manual valve (9) is in the rDJ position, the first to fourth speed transmission systems (G1) (G2) (G3
) (G4) is selectively established, and a signal (G4) from the engine throttle opening sensor (16a) is sent to the electronic control circuit qe consisting of a microcomputer as shown in FIG.
Other signals such as intake pipe negative pressure related to the engine load may be input), a signal from the vehicle speed sensor (16b), and a signal from the position sensor +j (16c) of the manual valve (9). The control circuit ○θ controls the both-side open valve (1) so that the speed change characteristics as shown in FIG.
51) Control opening and closing of (152).

In the drawings, (AI), (A2), (A3), and (A4) are accumulators installed to buffer sudden pressure changes when oil is supplied and discharged from each hydraulic clutch (CI), (C2, and C3HC4).
171 converts the line pressure input from the 14th oil passage (L14) connected to the 1st oil passage ([1) via the manual valve (9) to the throttle pressure as shown in the 5th diagram according to the throttle opening degree. The figure shows a throttle valve that regulates and outputs the pressure, and applies the throttle pressure from the throttle valve G7) to the accumulators (A2) (A3) (A4) for 2nd to 4th speeds as back pressure, and further applies the throttle pressure from the throttle valve G7) to the second oil passage ( A pressure reducing valve ae that is pushed to the right opening side by the throttle pressure is intervened in L2), and the supply pressure to the downstream side of the second oil passage ([2) is reduced in the low throttle opening range. I tried to let them do it. Incidentally, the pressure reducing valve (18) is known from Japanese Patent Application Laid-open No. 166750/1983, and detailed explanation thereof will be omitted.

Each of the oil drain passages (LDl) (1 port 2) ([port 3) (LD4
) are equipped with drain oil control valves (19+), (192), and (1), respectively.
93) (194) and the orifice parallel to this (20+
) (202) (20a) 1204),
Each control valve (line d (192) (193) (194)
) by closing and opening the respective oil drain passages (LDl) (LD2) (
The conduit resistance of LD3) (104) can be increased or decreased.

To explain this in more detail, the second oil drain path (L
The second oil drain control valve ('192) installed in D2) is pressed to the left to the opening side by the hydraulic pressure (hereinafter referred to as 4th speed pressure) of the 4th speed hydraulic clutch (C4) on the engagement side. When the 4th gear pressure rises to a predetermined pressure when shifting from 3rd gear to 4th gear, the control valve (192)
is opened, and before and after that, the 3-speed hydraulic clutch (C
3) The pressure drop characteristics of the oil pressure (hereinafter referred to as 3rd speed pressure) are differentiated between slow and fast, and the release timing of the 3rd speed hydraulic clutch (C3) is appropriately controlled to prevent engine revving and excessive overload. Smooth gear shifting can be achieved without causing engine stall. Also, when downshifting from 4th gear to 3rd gear, a third oil drain control valve (1
9a) is pressed to the left opening side by the 3rd gear pressure on the engagement side, opens by increasing the 3rd gear pressure, and functions to smoothly downshift from 4th gear to 3rd gear in the same way as above. do.

By the way, under driving conditions, such as sudden accelerator operation, the shift characteristics may be set so that the gears are shifted between 2nd and 4th gears, skipping 3rd gear. The first oil drain control valve (19+) installed in the first oil drain path (LDl) corresponding to C2) is used for both upshifting from 2nd gear to 3rd gear and upshifting from 2nd gear to 4th gear. In order to cope with this problem, it is assumed that the control valve (19z) is pressed to the right opening side by the 3rd speed pressure and the 4th speed pressure as known from Japanese Patent Application Laid-Open No. 61-84450, and the control valve (19z) is connected to the 2nd speed hydraulic clutch ( C2)
.

Press it to the left closing side with the hydraulic pressure (hereinafter referred to as 2nd speed pressure),
When shifting up from 2nd gear to 3rd gear or from 2nd gear to 4th gear, the pressure difference between the drop in 2nd gear pressure on the disengaged side and the increase in 3rd gear pressure or 4th gear pressure on the engaged side becomes less than a predetermined value. The valve was opened.

In addition, the differential pressure responsive type drain oil control valve is disclosed in Japanese Patent Application Laid-Open No. 61-82.
It is known from No. 051.

Also, when downshifting from 3rd gear to 2nd gear, the 3rd gear hydraulic clutch (
The fourth oil drain control valve (194) interposed in the fourth oil drain path (LD4) connected to C3) is pressed to the left opening side by the second speed pressure on the engagement side, and In order to cope with downshifting from speed to second speed, the third oil drain path (LD3) connected to the fourth speed hydraulic clutch (C4) is connected to the control valve (19a).
) to the common inflow boat (19*a) of the branch road (LD3a)
) so that the control valve (194) is connected to the third oil drain path (1,03) in parallel with the third oil drain control valve (193), and the control valve (194) is connected to the third oil drain path (1,03) in parallel with the third oil drain control valve (193), so that the control valve (194) is connected to the third oil drain path (1,03) in parallel with the third oil drain control valve (193). Even during downshifting, the 4th speed pressure on the disengaged side is quickly lowered due to the increase in the 2nd speed pressure on the engaged side. - In this case, when downshifting from 3rd gear to 2nd gear, before the fourth oil drain control valve (194) is opened, the inflow boat (194a) from the fourth oil drain path (LD4) and the third oil drain path (
The oil of the 3rd speed hydraulic clutch (C3) is discharged from the orifice (203) via the orifice (203), and the drop in 3rd speed pressure is determined by the orifice (20a) of the 4th oil drain path (LD4). The branch road (LD3a
) is provided with a check valve (21+) for preventing backflow of oil from the fourth oil drain path (LD4), and similarly, a check valve (21+) is provided in the fourth oil drain path (LD4) to prevent oil from flowing backward from the fourth oil drain path (LD4).
4) is provided with a check valve (212) that prevents backflow of oil from the third oil drain path (L port 3).

In addition, the third drain oil control valve (193) is added to the third speed pressure and the second
It is constructed so that it can be pressed in the opening direction even by rapid pressure, and 4
It is also possible to cope with a downshift from speed to second speed, but in this case, the control valve (193) must be formed with two stages: an oil chamber for the third speed pressure and an oil chamber for the second speed pressure. , said first
As with the drain oil control valve (191), the valve becomes large, and it may be difficult to incorporate it into the limited size valve block built into the transmission case. On the other hand, if the fourth drain oil control valve (19a) is used, a small control valve similar to the control valve dedicated to downshifting from 3rd gear to 2nd gear can be used to shift down from 4th gear to 2nd gear.
This is advantageous because it can also handle high-speed downshifts.

In the case of a 5-speed forward transmission, the oil drain path for the 5-speed hydraulic clutch is connected to the inflow boat (19+a) of the control valve (19a) to cope with downshifting from 5th to 2nd speed. It can be configured as desired.

Furthermore, when downshifting in the low throttle opening range, a smoother gear shift can be achieved by quickly reducing the clutch pressure on the disengagement side.
As is known from No. 1, a fifth oil drain control valve (19s) that is opened at a low throttle opening is provided in the third oil drain path (L'03) in parallel with the third oil drain control valve (193), and 4 oil drain path (
A fifth oil drain control valve (19s) that is opened at a low throttle opening is arranged in parallel with the fourth oil drain control valve (194) in the fourth oil drain path (LD4), and a fourth drain oil control valve (194) in the fourth oil drain path (LD4). The sixth drain oil control valve (194) is opened at a low throttle opening in parallel with the sixth oil drain control valve (194).
c), and here the sixth drain oil control valve (19s)
is composed of a plunger that presses the throttle valve (+7). ~Operators linked to the listening level (19
sa) shall be pushed to the left to the closed side, and the fifth
The drain oil control valve (19s) is similarly pushed to the left by the operator (195a) linked to the throttle opening, and at low throttle opening, each control valve (η5) (
19a) is returned to the right open position, and the speed changes from 3rd gear to 2nd gear.
When downshifting from 4th gear to 3rd gear or 4th gear to 2nd gear, 3rd gear pressure and 4
The rapid pressure was made to drop quickly by draining oil through the respective control valves (19s) (196). Further, the fifth drain oil control valve (196) has a small diameter stepped portion (19S b
), and when the throttle opening is high, the third oil drain passage (LD3) is connected to the right atmospheric release port through the step (19sb), and when downshifting from 4th gear, the 4th gear pressure is The descent has been made faster.

This is because the shift characteristics are generally set so that the higher the throttle opening, the higher the vehicle speed.In this case, as the vehicle speed increases, the engine speed changes before and after downshifting. As the amount increases, when downshifting with a high throttle opening, the clutch pressure on the high gear side is lowered early and a neutral state is slightly formed before the low gear is established by increasing the clutch pressure on the low gear side. However, if the engine is revved up a little at this point, the difference in rotation between the input side and the output side of the hydraulic clutch in the low gear will be reduced, the clutch will engage smoothly, and a smooth downshift will be performed. .

Also, when a downshift from 3rd gear to 1st gear is performed, the second oil drain path (LD2) connected to the 3rd gear hydraulic clutch (C3)
The second oil drain control valve (+92) installed in 1st speed transmission system (
It takes time for G1) to be established, resulting in poor acceleration. Therefore, the second oil drain passage (L port 2) is connected to the oil drain boat (10+g) through the annular groove (101f) formed in the second shift valve (IG+) at the first gear position. At the time of such kickdown, the oil of the 3rd speed hydraulic clutch (C3) is drained from the oil drain boat (10+ IJ) without throttling resistance, and the 1st speed transmission system (G1) is established without time lag. In addition, manual valve (9)
At the rDJ position, the first speed hydraulic clutch (C1) is always engaged, and the first speed transmission system (G1) is established when the third speed hydraulic clutch (C3) is released.

The oil passage configuration at the rDJ position of the manual valve (9) has been explained above, but the oil passage configuration is the same at the "S" position as at the rDJ position, and the first and second atmosphere release valves (15+) (15
2) By switching the speed change characteristics stored in the electronic control circuit 0e that opens and closes, automatic speed change from 1st speed to 4th speed is performed with the speed change characteristics shown in FIG. 7, for example. The shift characteristics shown in FIG. 7 are set to be faster than those shown in FIG. 6, and are suitable for sporty driving and mountain driving.

In addition, the 7th oil passage (L7) and the 8th oil passage ([8]
was connected to the manual valve (9) through the notched groove (9b), but in the "S" position, the annular groove (9d) of the valve (9)
), the two oil passages (L7HL8) are connected.

At the “2” position of the manual valve (9), the first oil passage ([1)
The first valve (90) connected to the valve (90) via the notch (90)
The fourth oil passage (L14) is connected to the eighth oil passage (L8) via the annular R (9d) of the valve (9), and the line pressure is transferred to the second shift valve without going through the first shift valve (10+). (102). Here, in the "2" position, the first and second atmosphere release valves (13+) (132) are both opened, the second shift valve (102) is in the second gear position on the right, and the eighth oil path ([8)
is connected to the ninth oil passage (L9), and the second-speed hydraulic clutch (C
2) is refueled and a 2-speed transmission system (G2) is established.

In addition, in the "2" position, the second oil passage (S2) is connected to the oil drain hole (9[) consisting of the shaft hole formed in the manual valve (9).
), and the first speed hydraulic clutch (C1) is not supplied with oil. In addition, at the rDJ "S" position, the oil drain hole (
The 15th oil passage (Ll5) connected to the oil chamber (102b) at the left end of the second shift valve (102), which was connected to (L6), and the oil pressure of the oil chamber (102b) can be controlled by the second atmosphere release valve (152). This is due to some kind of malfunction and the first and second atmosphere release valves (1st)
Even if it becomes impossible to energize the solenoid (152) and the both popular release valves (15+) (Is 2) remain closed (4th gear state at rDJrsJ position),
This is to establish a 2-speed transmission system (G2) by setting the manual valve (9) to the "2" position, thereby making it possible to obtain strong driving force. That is, in the "2" position, the first atmosphere release valve (
Even if the modulator pressure is input to the right end oil chamber (10□a) of the second shift valve (102) due to the closing of the second shift valve (102), the left end oil chamber (10
The modulator pressure is also input to 2b), and the left and right pressing forces due to the modulator pressure are balanced and the spring (102
C), the second shift valve (102) is switched to the right 2nd speed position, and the 2nd speed hydraulic clutch (C2) is refueled.

Also, the reason why the 2nd speed hydraulic clutch (C2) is supplied with oil through the second shift valve (102) at the "2" position is because of the "2" position.
This is to make it possible to establish a three-speed transmission system (G3) depending on the program of the electronic control circuit even in the position . In other words, the manual valve (
9) to the "2" position may cause an engine overrun or a large shift shock. To avoid this, for example, at a predetermined high vehicle speed or higher, the 3rd speed transmission system ( G3) can be established in order to enable such control.

In this case, the first oil passage (Ll
) is connected to the second oil passage (L2), and the first shift valve (10
It is also possible to supply oil to the second shift valve (1 (h)) through the second shift valve (1 (h)), but in this case, if the 1st speed curve pressure clutch (C1) fails, it will cause future oil leakage,'' rDJ said.
Not only at the rsJ position but also at the "2" position, due to the drop in line pressure, all of the i+I+ pressure clutches cannot be engaged, causing a problem in which forward travel is impossible.

However, according to the above configuration, in the "2" position, the second
Since oil is supplied directly to shift 1 to valve (102), forward travel is possible at least in the "2" position, and the above-mentioned problems do not occur.

At the rRJ position of the manual valve (9), the first oil path (Ll)
is connected to the 16th oil passage (11B) connected to the first shift valve (10+) via the notch groove (9j) of the manual valve (9), and in this case, the electronic control circuit ae controls the first atmosphere release valve (15+). ) is open, the second atmospheric release valve (152) is open (3rd gear state at rDJ rsJ position), and the first shift valve (10+) is switched to the left 2nd gear position. 16th via the annular groove (1o+h) of the valve (10+)
The oil passage (116) is connected to the left end oil chamber (11a) of the Nervo valve (11).
), the servo valve (11) moves to the right against a spring (11b) by line pressure input through the 17th oil path (117), The select gear (6) connected to the nervo valve 01) is switched to the right reverse position, and the 17th oil passage (L) is switched to the right reverse position.
Is l7) the oil? , servo valve av connected to (11a)
It is connected to the 18th oil passage (118) connected to the manual valve (9) through the shaft hole (11C).

The 18th oil passage (Ll8) is the rRJ of the manual valve (9).
4-speed hydraulic clutch (C) via notch m (9C) at position
4) is connected to the 13th oil line (Ll3),
Thus, by supplying oil to the 4-speed hydraulic clutch (C4) and switching the selector gear (6) to the reverse position, the reverse transmission system (GR) is activated.
is established.

In addition, according to the right movement of the servo valve (Itl) to the reverse position, the 19th)d] path (Ll9) connected to the oil chamber (10, b) at the left end of the third shift valve (10a) is in the position of the servo valve (Itl). Notch groove (1
1d) and the spring chamber (11c).
The oil chamber (103b) is connected to the atmosphere by the oil drain port (9k) connected to the 14th oil passage (Ll4) via the annular groove (9a) at the rRJ position of the manual valve (9). It is opened, but the manual valve (9) is moved from the rRJ position to r.
When switching to the DJ "S" position, if the return to the forward position of the nervo valve a is delayed as described later, in the rDJ "S" position, the 14th oil passage (114) is connected to the 1st oil passage (L) as described above.
l) is connected, the oil chamber (1
Line pressure is input to 03b), and the third shift 1 to valve (
103) is forcibly held in the third gear position on the right. The reason is as follows.

That is, in a transmission that performs speed change control from the electronic control circuit aO, if an abnormality occurs in the input signal system such as the vehicle speed sensor (16b), normal speed change control cannot be performed. This may cause malfunctions such as engine overrun, and such transmissions may cause problems such as engine overrun.

Generally, a self-diagnosis 1fl'i function for detecting an abnormality in the force signal system is added to the electronic control circuit ae, and when an abnormality is detected, the gear shift is controlled to establish the highest speed. , the state is in the fourth gear, that is, the state in which both the first and second atmospheric release valves (15+) and (152) are closed.

Therefore, if the manual valve (9) is switched from the rRJ position to the rDJ rsJ position when an error has occurred in the input signal system, the 4th speed hydraulic clutch (C4) will continue to be supplied with oil, and in this case, the servo valve Gv will continue to be supplied with oil. From the oil chamber (11a) to the 17th oil passage (Ll7) and the first shift valve located in the 2nd gear position (
10+) annular groove (io + h) and the 16th oil passage (Ll
6) and the notched groove (9J) of the manual valve (9) to the oil drain boat (91), but if the oil is cold and has high viscosity, the oil will be drained from the oil chamber (11a). Therefore, the servo valve (
The movement of the Iv to the left forward position was delayed, and the manual valve (9
) to the rDJ rsJ position, the selector gear (6) may remain in the reverse position, and in combination with refueling the 4th speed hydraulic clutch (C4), the reverse transmission system (GR) continues to be activated.
is established, and on the other hand, when switching to the rDJ "S" position, the 1st speed hydraulic clutch (C1) is also supplied with oil, so the reverse transmission system (Gl+) and the 1st speed transmission system (G1) are established simultaneously. Therefore, the 1st and 4th speed hydraulic clutches (C1) (C4
) may cause burnout or premature wear of the clutch disc.

However, according to the above configuration, if the movement of the forward position of the servo valve (+1) is delayed, a line is sent to the oil chamber (103b) at the left end of the third shift valve (10a) via the 19th oil passage (Ll9). Since the pressure is input, even if the modulator pressure is input to the oil chamber (103a) at the right end by closing the second atmosphere release valve (152), there is no push to the right due to the line pressure and the spring (10tC). The pressure is released and exceeds the left pressing force caused by the Schlater pressure, and the 3rd shift valve (103) is held at the 3rd gear position on the right, draining oil from the 4th gear hydraulic clutch (C4) and discharging the oil from the 3rd gear hydraulic clutch. (C3) is refueled, and the 3rd speed transmission system (
G3) is established and does not cause the above problem.

In addition, at the rRJ position, the servo valve 0 is
When the vehicle is moving forward at a certain speed or higher, refueling is done by switching the first shift valve (10d) to the 1st gear position and refueling both curves (
L16HL17) connection and reverse transmission system (GR)
This is to prevent the establishment of In this case, rD
J rsJ When returning the r2J from the forward position to the rNJ position, if the vehicle speed is above a certain value, the first shift valve (1 (h) is switched to the 1st speed position in advance, and the reverse transmission system (GR ) to ensure that it is possible to prevent the establishment of

At the rNJ position of the manual valve (9), the first oil passage ([1)
The modulator valve a3 is only supplied with oil from the r
The same applies to the PJ position.

Note that the first and second atmospheric release valves (15+) (Is 2) are normally closed types, but this means that if the eight valves (15+) (152) are normally closed types, the solenoid (15a) will not be energized. It is necessary to generate a large excitation force to open the eight valves (15+) (152) against the biasing spring and modulator pressure in the opening direction of the eight valves (15+) (152). , as the valves become larger, in the normally closed type, when the solenoid (15a) is energized, the pressing force due to the modulator pressure is subtracted from the spring force of the biasing spring that closes each valve (151) (152). This is because the valve can be opened with a relatively small excitation force and the valve can be made smaller. Also, both valves (15+) (1
When the vehicle is cruising in the fourth gear with valve 52) closed, there is an advantage that power supply to both valves (15+) (Is 2) can be stopped, thereby reducing power consumption.

This concludes the explanation of the speed change control at each position of the manual valve (9), and next, the clutch (2) built in the fluid torque converter (3) will be explained.

Referring to FIG. 2, the clutch (2) mechanically connects the input side of the fluid torque converter (3), for example, the input case (3a), and the output side, for example, the turbine impeller (3b). A damper spring C2 is attached to the turbine wheel (3b) in the gap between the input case (3a) and the turbine wheel (3b).
The clutch plate C) 2a) connected via the torque converter (C) 2b) is configured to be movable in the axial direction.
The internal gap of 3) is divided into the impeller storage chamber ■ and the back pressure chamber ■ on the input case (3a) side by the clutch plate d2a), and the internal gap is divided from the back pressure chamber ■ side by the control valve ■ described later. The clutch can be freely switched between a released state in which oil is supplied to the storage chamber and a clutch engaged state in which oil is supplied from the side of the storage chamber.In the stopped state, the internal pressure of the storage chamber The clutch plate C22a) is frictionally engaged with the input case (3a) by an engagement force according to the differential pressure between the internal pressure of QΦ (hereinafter referred to as pb).

The control valve (2) connects a 20th oil passage (L20) connected to one regulator valve a to a 21st oil passage (L21) connected to a back pressure chamber [phase].
) to supply oil to the back pressure chamber [phase] (the position shown in the figure), and the 22nd oil passage (L22) which connects the 20th oil passage (L20) to the blade wheel storage chamber. ) to supply oil to the storage chamber, and a fourth oil passage (25a) at the right end of the control valve
Modulator pressure (hereinafter referred to as Pm) is input through [4], and the 23rd oil passage (23
An oil passage (L23) is connected, and an electromagnetic normally-closed third atmosphere release valve (153) is connected to the 23rd oil passage (123), and when the valve (153) is opened, both the Oil chamber (2sa) (25
The control valve (2) was switched to the engagement position against the spring (2Sc) by the pressure difference in b), so that the clutch was engaged.

In the drawing, ■ is the first WA pressure valve consisting of a check valve installed in the fifth oil drain (LD5) connected to the quadruple storage chamber in order to regulate Pa to a relatively high predetermined value, ■ is the oil cooler, and ■ is the first WA pressure valve. Oil reservoir, ■1) (En 2) is oil cooler■
This shows a relief valve installed to prevent the inflow pressure to the lubricating part from rising excessively.

Here, the stopped state of the clutch ■ is a direct connected state in which the input side and the output side of the clutch ■ are directly connected due to a change in the engagement force due to an increase or decrease in the differential pressure between pa and pb, and a directly connected state in which the input side and the output side of the clutch ■ are prevented from slipping. The system is configured as follows to variably control this differential pressure depending on the driving condition.

That is, the 21st oil passage (L
21), a 24th oil passage (L24) connected to
A 25th oil passage branched from the 2 oil passage (L22) is provided with a 25), and both oil passages (L24) (125) are connected via a second pressure regulating valve (■) to create back pressure chambers Q@ and W. A communication path is configured to communicate with the vehicle storage room (■), and a sixth oil drain path (LD6) parallel to the first pressure regulating valve is connected to the fifth oil drain path (LD5). An on-off valve (2) is provided, and the on-off valve (2) is configured to switch between the left closing side and the left side by the throttle pressure (hereinafter referred to as t's) from the throttle valve (2) inputted to the right end oil chamber (32a). The left end oil chamber (xb) is connected to the 4th oil path (L4) via orifice @2) through the 26th oil path (126).
It is assumed that the valve is pressed to the right opening side by the input Pm and the spring (32c), and an electromagnetic regular m-type fourth atmosphere release valve (154) is connected to the 26th oil passage (126). , the release valve (Isa) is opened and pe is greater than or equal to the predetermined value Ps (
The opening/closing valve (1) is opened and closed only when the throttle opening is a predetermined opening (08 or more), and the fourth atmospheric release valve (15a
) is closed and when Pm is input to the left end oil chamber ('!2b), the opening/closing valve (2) is not closed even if the throttle 1 is fully opened.

The second pressure regulating valve (■) has an on-off valve (■) in the sixth oil drain path (L12).
The hydraulic pressure input through the 27th oil passage (L27), which is connected when the valve opens, is Pa, and the right opening side and the 24th oil passage (1
The second pressure regulating valve (24) is configured to be of a differential pressure responsive type that is pressed toward the left closing side by the hydraulic pressure input via the oil passage (L24a) from the pylon 1 connected to the pylon 1 (L24a).
the closed side at PO from throttle valve 0D, and the 26th
Pm input via the oil path (12G) and the spring (31
a) so that it is pressed to the open side. Therefore, the pressure receiving areas of Pa and pb of the second pressure regulating valve
When the pressure receiving area of ll is 82 and the force of the spring (31a) is F, the relationship between the forces acting on the second pressure regulating valve GD is as follows: Pa51+Pm52+F=PbS1+Pe5
2, and the following relational expression is established.

Here, the third and fourth atmosphere release valves (153) (15
a) is the first and second atmosphere release valve (Is) for speed change control;
+) Similarly to (i52), opening and closing are controlled by an electronic control circuit (IG).

Fig. 8 shows the operating characteristics of the clutch ■, and the third atmosphere release valve (153) is opened in the region on the high speed side from the line a in the figure.
As described above, the control valve (1) was switched to the engaged position, the clutch was engaged, and the fourth atmosphere release valve (154) was opened in the area surrounded by bIIJ in the figure.

Therefore, in the area surrounded by line b and the throttle opening is 8
The closing condition of the above-mentioned on-off valve ■ is satisfied only in the A region of Fig. 8 which is 3 or more, and in the 8 region below θS surrounded by the b line and the C region between the a line and bII. The on-off valve ■ is held in the open state, and Pa becomes relatively low pressure due to oil draining through the sixth oil drain path (LO6), and also through the second pressure regulating valve ■ to the back pressure chamber Q@. oil is drained, the differential pressure between Pa and Pb increases as the throttle opening increases according to equation (1) above, and the clutch engagement force increases in accordance with the engine output torque due to the increase in the throttle opening. Therefore, the clutch (2) operates in a slipping state so that the speed ratio of the torque converter (3) remains constant regardless of increases or decreases in the output torque.

Here, in the C region, the fourth atmosphere release valve (15a) is closed, so Pw+ is input to the 211th pressure valve ■, but in the B region, the fourth atmosphere release valve (15a) is opened, so that Pw+ is inputted to the 211th pressure valve ■.
Since the input of m is stopped, the differential pressure between Pa and pb becomes (1)
The torque converter (
The speed ratio of 3) is maintained at about 0.92 to 0.93 in the C region, so that torque fluctuations that tend to increase in low vehicle speed ranges and low throttle opening ranges can be effectively absorbed by clutch ■ slipping. In region B, where the throttle opening is not extremely low and torque fluctuations are hardly a problem, it is possible to obtain an engagement force that can barely maintain the speed ratio at 1.0, and the clutch ■ This prevents deterioration in fuel efficiency due to slippage.

Also, when decelerating with the throttle opening at an extremely low opening of θ0 or less, which is close to full throttle, torque fluctuations from the engine are not a problem, so even in the region between the a line and the b line, the θ . In the D region below, the speed ratio of the torque converter (3) is fed back to the fourth atmosphere release valve (Isa
) is duty-controlled so that the amount valve time per unit time is changed according to the deviation from the target speed ratio, and the speed ratio is set to 1.
02 to 1.03 to maintain good engine braking effectiveness and prevent vehicle body vibration from occurring during engine braking.

In the above-mentioned region A, the on-off valve (■) is closed, oil drainage via the sixth oil drain path (LD6) is stopped, and Pa is
The pressure is maintained at a relatively high value set by the A pressure valve ■, and Pa is input to the second m pressure valve ■ via the 27th oil passage (L27), and the 26th oil passage (126) is opened. The input of Pl is stopped, and the second pressure regulating valve ■ is pushed to the closed position by Pa (more than Ps) against the spring (31a), and the back pressure chamber [
The oil supply to the [phase] is stopped, pb becomes a value close to atmospheric pressure, the differential pressure between Pa and pb becomes large, and the clutch operates in a directly connected state.

In the drawing, ■ indicates the first to fourth atmosphere release valves (15+) (15
2) (153) (154) and the oil filter provided upstream of the modulator valve 03 and the throttle valve (I7), (15b) each air release valve (15d ( Is 2) (15a
) (154) is a drive circuit that energizes the solenoid (15a); (16d) is an engine rotation speed sensor; The speed ratio of the torque converter (3) is determined from the rotation speed and the engine rotation speed.

(Effects of the Invention) As described above, according to the present invention, even if the shift valve is controlled by the electronic control circuit so as to supply oil to the hydraulic clutch of the transmission system of the highest speed gear when the input signal system of the electronic control circuit is abnormal, If there is a delay in returning the servo valve to the forward position when the manual valve is switched from the reverse position to the automatic shift position, oil supply to the hydraulic clutch of the highest speed transmission system will be blocked, and the reverse transmission system will not be established. This has the effect of reliably preventing problems such as burnout and wear of the hydraulic clutch due to simultaneous establishment of the lowest speed transmission system and the reverse transmission system.

[Brief explanation of the drawing]

FIG. 1 is a line diagram of an example of a transmission to which the present invention is applied, FIG. 2 is a hydraulic circuit diagram thereof, and FIG. 3 is an enlarged view of the main parts of the hydraulic circuit.
Figure 4 is a block circuit diagram of the electronic control circuit, Figure 5 is an output characteristic diagram of the throttle valve provided in the hydraulic circuit, Figure 6 is a shift characteristic diagram of the manual valve at the rDJ position, and Figure 7 is its "S"
FIG. 8 is a diagram showing the operating characteristics of the clutch for the i~silk converter. (G1)...1st speed transmission system (second transmission system) (G2)
...2nd speed transmission system (G3)...3rd speed transmission system (third transmission system) (C4)
... 4-speed transmission system (first transmission system) (GR) ... Reverse transmission system (C1) (C2HC3) (C4) ... Hydraulic clutch (
6)...Selector gear (7)...One-way clutch (8)...Hydraulic pressure source (9)...Manual valve (IG+)...1st shift valve (102)...
・Second shift valve (10a)...Third shift valve (shift valve that supplies and drains oil to the hydraulic clutches of the first and third transmission systems) (10s b)...Oil chamber ( 11)
...Removal of servo valve Figure 6 Figure 7 Vehicle compliance procedure amendment form

Claims (1)

[Claims] It is equipped with a plurality of forward transmission systems each established by engagement of each hydraulic clutch, a first transmission system serving as the highest forward speed, and a reverse transmission system sharing the hydraulic clutch, and a second transmission system serving as the lowest forward speed.
A hydraulically actuated transmission for a vehicle, which is provided with a one-way clutch that allows over-rotation on the output side to intervene in the transmission system of the transmission system, and a selector gear that selectively establishes the first transmission system and the reverse transmission system. In addition, in the hydraulic circuit that controls these hydraulic clutches and selector gears, there is a manual valve that can be operated to switch between the automatic transmission and the reverse position, and a selective valve for each hydraulic clutch in the forward transmission system except for the second transmission system. A hydraulic clutch in the second transmission system is constantly supplied with oil from a hydraulic source at the manual valve's automatic shift position. At the same time, these shift valves are switched and controlled by an electronic control circuit to automatically shift gears, and when the manual valve is in the reverse position, the servo valve is hydraulically pushed to the reverse position where the selector gear selects the reverse transmission system, and the servo valve is A hydraulic clutch of a first transmission system is supplied with oil through a valve, and the hydraulic clutch of the first transmission system and another third transmission system are supplied with oil through a valve.
An oil chamber is formed in the shift valve that controls the supply and discharge of oil to and from the hydraulic clutch of the transmission system to push it toward the switching device that supplies oil to the third hydraulic clutch, and the manual valve moves to the automatic shift position. When the servo valve is in the reverse position at the time of switching, the oil chamber is connected to the hydraulic power source via the manual valve and the servo valve, and the shift valve is in the reverse position regardless of control by the electronic control circuit. A control device for a hydraulically operated transmission for a vehicle, characterized in that the control device is configured to be restrained by the following.