JPH01295058A - Controller for hydraulic operation type transmission for vehicle - Google Patents

Abstract

PURPOSE:To reduce the shock on the selection of a manual valve by starting the transmission of torque in a high speed transmission system through the selection of the traveling range of the manual valve and then starting the torque transmission in a low speed transmission system through a control valve when the oil pressure increases to a prescribed value. CONSTITUTION:When start is performed by switching a manual valve 9 to D4 or D3 range, the second speed hydraulic clutch C2 is supplied with oil through the oil passages L3, L15, L5, L7 and L8, and the second speed pressure is increased, and a relatively low torque is transmitted onto driving wheels by the transmission of torque through the second speed transmission system. When, the second speed pressure rises to a prescribed value, a control valve 12 is switched to the second position, the oil in the second speed hydraulic clutch C2 is discharged from an oil discharge port 12c, and the second speed pressure lowers, and the hydraulic pressure in the first hydraulic clutch C1 is increased by the oil supplied through a hydraulic passage L4, and the transmission of torque through the first speed transmission system is started, and the stepwise increase is performed. Thus, the shock on the selection of the manual valve can be reduced.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention provides a one-way transmission system that includes at least two stages of a low-speed transmission system and a high-speed transmission system, and that allows the low-speed transmission system to over-rotate on the inside and outside. The present invention relates to a control device for a hydraulically operated vehicle transmission that uses a clutch.

(Prior art) Conventionally, in this type of transmission,
As seen in Publication No. 750, a hydraulic circuit that controls the supply and discharge of oil to a low-speed hydraulic engagement element that establishes a low-speed transmission system and a high-speed hydraulic engagement element that establishes a high-speed transmission system has a neutral range and a running range. A manual valve that can be switched between at least two ranges and a shift valve that can be switched between a low speed position and a high speed position is provided, and when the manual valve is switched to the travel range, the low speed hydraulic engagement element and the The high-speed hydraulic engagement element is supplied with pressure oil from a hydraulic source via the shift valve in its high-speed position, and when the manual valve is switched from the neutral range to the travel range and the vehicle starts moving, the low-speed hydraulic engagement element is first engaged. A low-speed transmission system is established by lubricating only the elements, and then the high-speed hydraulic engagement elements are refueled by switching the shift valve to the high-speed position to establish a high-speed transmission system.

At this time, torque transmission via the low-speed transmission system is automatically stopped by the action of a one-way clutch interposed therein.

However, in this case, when the manual valve is switched to the travel range, a large drive torque is suddenly transmitted to the drive wheels of the vehicle via the low-speed transmission system, which tends to cause a switching shock.

Therefore, the applicant of this application first filed the patent application No. 62-103067.
According to the above No., first and second oil passages are provided which are connected to a hydraulic pressure source when the manual valve is in the travel range, and a low-speed hydraulic engagement element is connected to the second oil passage, and the second oil passage is connected to a low-speed hydraulic engagement element. A third oil passage connected to the oil passage via a control valve is provided, and a shift valve is connected to the high-speed hydraulic engagement element. The first oil passage is selectively connected to the first oil passage at the high speed position, and the third oil passage is selectively connected to the third oil passage at the low speed position, and the control valve is set to an open position where the second and third oil passages are communicated with each other. and a closed position in which communication between the two oil passages is cut off and the third oil passage is connected to the oil drain port, and the control is performed by increasing the oil pressure of the low-speed hydraulic engagement element to a predetermined pressure. We proposed a system in which the valve could be switched to the closed position.

According to this, when the manual valve is first switched to the travel range,
The low-speed hydraulic engagement element is simultaneously supplied with oil through the second oil passage, and the high-speed hydraulic engagement element is supplied with oil from the second oil passage through the control valve, the third oil passage, and the shift valve located at the low-speed position. , when a relatively low torque is transmitted to the drive wheels via the high-speed transmission system, and then the hydraulic pressure of the low-speed hydraulic engagement element rises to a predetermined pressure and the control valve is switched from the open position to the closed position, the third oil The oil of the high-speed hydraulic engagement element is discharged from the oil drainage board via the oil discharge board, torque transmission via the low-speed transmission system is started, and the drive torque acting on the drive wheels gradually rises gradually. Switching shock is reduced.

(Problem to be Solved by the Invention) In the above system, the difference in pipe resistance between the oil passage from the second oil passage to the low-speed hydraulic engagement element and the oil passage from the high-speed hydraulic engagement element causes oil At low temperatures, when the viscosity increases and the pipe resistance becomes more susceptible, the oil pressure of the low-speed hydraulic engagement element rises to a predetermined pressure while the oil pressure of the high-speed hydraulic engagement element is low, and the control valve switches to the closed position. Otherwise, the above-mentioned effects may not be obtained.

SUMMARY OF THE INVENTION In order to solve this problem, it is an object of the present invention to provide a device that can reliably establish a high-speed transmission system prior to a low-speed transmission system when switching a manual valve to a travel range.

(Means for Solving the Problem) In order to achieve the above object, the invention of claim 1 includes at least two stages of transmission system, a low speed transmission system and a high speed transmission system, and the low speed transmission system has an overdrive on the output side. A control device for a hydraulically operated transmission for a vehicle that includes a one-way clutch that allows rotation, comprising a low-speed hydraulic engagement element that establishes the low-speed transmission system and a high-speed hydraulic engagement element that establishes the high-speed transmission system. A hydraulic circuit for controlling oil supply and discharge to and from the vehicle is provided with a manual valve that can be switched between at least two ranges, a neutral range and a travel range, and a shift valve that can be switched between at least two positions, a low speed position and a high speed position. A first oil passage and a second oil passage are provided which are connected to a hydraulic power source when the manual valve is in a travel range, and a third oil passage is connected to the second oil passage via a control valve. is provided, the first oil passage is selectively connected to the high-speed hydraulic engagement element at the high speed position of the shift valve, and the third oil passage is connected at the low speed position of the shift valve, and the control valve is , a first position where the second and third oil passages communicate with each other, a fourth oil passage where communication between the two oil passages is cut off and the second oil passage is connected to the low-speed hydraulic engagement element, and a third oil passage. The oil passage is configured to be switchable to a second position where the oil passage is connected to the oil drain port, and the control valve is switched to the second position when the oil pressure of the high-speed hydraulic engagement element rises to a predetermined pressure.

In this case, as in the invention of claim 2, the control valve is configured to be gradually moved to the second position side as the hydraulic pressure of the high-speed hydraulic engagement element increases, and the control valve is moved between the first position and the second position. Both the third oil passage and the fourth oil passage may be communicated with the second oil passage in an intermediate region between the two positions.

(Function) When the manual valve is switched to the travel range, the control valve is initially in the first position, so the high-speed hydraulic pressure is The engagement element is lubricated and torque is transmitted through the high-speed transmission system. Then, when the hydraulic pressure of the high-speed hydraulic engagement element rises to a predetermined pressure, the control valve is switched to the second position and the high-speed hydraulic engagement is performed. The oil in the element is discharged from the oil drain port via the third oil passage, and is supplied to the low-speed hydraulic engagement element via the second oil passage and the fourth oil passage, and is then supplied to the low-speed hydraulic engagement element via the low-speed transmission system. Torque transmission begins.

As described above, the control valve does not switch to the second position unless the hydraulic pressure of the high-speed hydraulic engagement element rises to a predetermined pressure, so even if there is a delay in increasing the pressure of the high-speed hydraulic engagement element at low temperatures, the low-speed transmission system A high-speed transmission system is reliably established in advance, the drive torque acting on the drive wheels of the vehicle rises gradually, and the shock when switching the manual valve is reduced.

By the way, if there is a delay in increasing the pressure of the low-speed hydraulic engagement element after the control valve is switched to the second position, the engine may become temporarily in a neutral state after the gear change and the engine may start to rev up.

In this case, according to the invention of claim 2, oil supply to the low-speed hydraulic engagement element is started before the control valve is switched to the second position,
By the time oil is drained from the high-speed hydraulic engagement element by switching the control valve to the second position, the oil pressure of the low-speed hydraulic engagement element has risen to the extent that low-speed transmission is possible without causing the engine to rev up. The system is established smoothly.

(Example) Referring to FIG. 1, (1) shows a transmission that performs four forward speeds and one reverse speed, and the transmission (1) includes an engine (2) and a fluid torque converter (3). A 1st to 4th speed transmission system for forward movement is connected between an input shaft (la) connected to the drive wheels (4) of the vehicle through a differential gear (5) and an output shaft (1b) connected to the drive wheels (4) of the vehicle through a differential gear (5). (Gl) (G2) (G3XG4) and a reverse transmission system (GR), each forward transmission system (Gl
) (G2) (G3) (G4) and each hydraulic clutch (C1) (C2) (C3) for 1st to 4th speed which is a hydraulic engagement element.
(C4) intervenes, and each hydraulic clutch (C1) (C2
) (C3) and (C4), each transmission system (Gl
) (G2) (G3) (G4) are selectively established, and the reverse transmission system (GR) is set to the 4-speed transmission system (G4).
) and the 4-speed hydraulic clutch (C4) on the input shaft (la), and both transmission systems (G4) (GR) The gear (6) is switched to the counter gear (G4a) of each transmission system (G4) (GR) by switching between the forward direction on the right side and the reverse side on the right side.
(GRa) to be selectively established.

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

Each of the hydraulic clutches (C1) (C2) (C3) (C
4) is one whose oil supply and discharge is controlled by a hydraulic circuit shown in FIG. "R", neutral range rNJ.

"D4" automatically shifts from 1st to 4th speed, which is the driving range.
'', the rD3J automatically shifts from 1st to 3rd speed, and the 2nd speed holding range is ``2'', a manual valve (9) that can be operated to switch freely to a total of 6 ranges, and a manual valve (9) that can be switched depending on the vehicle speed and throttle opening. a manual valve (
9) in the "0." range, the first
A second oil passage (L2) in which the oil passage (Ll) is connected to the shift valve 00.
It is connected to the shift valve (IO) to supply oil to the 2nd to 4th speed hydraulic clutches (C2) (C3) (C4), and the third oil passage (L2) branched from the second oil passage (L2). The first speed hydraulic clutch (CI) is supplied with oil via the fourth hydraulic clutch (L4) connected to the control valve (L3) via a control valve (2) which will be described in detail later.

Even if the 1st speed hydraulic clutch (C1) is engaged, if the 2nd speed transmission system (G2) is established by refueling the 2nd speed hydraulic clutch (C2), the 1st speed transmission system (G2) is established by the action of the one-way clutch (7). Torque transmission via the speed transmission system (Gl) is automatically stopped, and the gear is shifted up from first gear to second gear.

The shift valve GO is a first shift valve GO for shifting between 1st and 2nd speeds on the upstream side.
a shift valve (10+), and a second shift valve (for intermediate 2nd-3rd speed shifting) connected to this via a fifth oil passage (L5).
102), and a third shift valve (10a) for third-speed to fourth-speed shifting on the downstream side connected to this via a sixth oil passage (L6).
and each shift valve (10+) (to 2) (
A governor pressure corresponding to the vehicle speed from the governor valve a3 is applied to the right end of the to 3), and a throttle pressure corresponding to the throttle opening from the first throttle valve (14d) is applied to the left end. Due to pressure, the first shift valve (1(
h) is switched from the first speed position on the right side to the second speed position on the left side, and the second oil passage (L2) is transferred to the second oil passage (L2) via the fifth oil passage (L5) to the second oil passage on the outflow side of the second shift valve (102). The 2nd speed hydraulic clutch (C2) is connected to the 7th oil passage (Ll) through the 8th oil passage (L8), which is connected to the 7th oil passage (Ll) in the "D4" range of the manual valve (9). Pressure oil is supplied from the hydraulic source (8) to shift up from 1st gear to 2nd gear, and when the vehicle speed further increases, the second shift valve (t(h) shifts from 2nd gear position on the right side to 3rd gear position on the left side). The fifth oil passage (L5) is switched to the position
is switched and connected from the seventh oil passage (Ll) to the sixth oil passage (L6), and the ninth oil passage (L9) on the outflow side of the third shift valve (103) is connected to the sixth oil passage (L6).
) to the third-speed hydraulic clutch (C3) and the seventh
The oil passage (Ll) is connected to the first oil drain passage (LDI) via the second shift valve (102), and the second-speed hydraulic clutch (C2)
When the vehicle is shifted up from 2nd to 3rd gear and the vehicle speed increases further, the third shift valve (103)
is switched from the 3rd gear position on the right side to the 4th gear position on the left side, the 6th oil passage (L6) is switched and connected from the 9th ura passage (L9) to the 1st O oil passage (LIO), and the 10th ura passage (LIO) is connected to the 4-speed hydraulic clutch (C4) via the 11th oil passage (Lll) connected to the "D4" range of the manual valve (9), and the 9th oil passage (L9) is connected to the 3rd It is connected to a second oil drain path (LD2) via a shift valve (103) to drain oil from a third-speed hydraulic clutch (C3), thereby allowing upshifting from third to fourth speed.

Also, according to deceleration, the third shift valve (10a) is
After returning to the speed position, the first O oil passage (LIO) connects with the third oil drain passage (LD3) and the ninth oil passage through the third shift valve (103).
The oil passage (L9) is connected to the sixth oil passage (L6) as described above, and oil is drained from the 4th speed hydraulic clutch (C4) and oil is supplied to the 3rd speed hydraulic clutch (C3). When the vehicle speed is downshifted to 3rd gear and the vehicle speed further decreases, the second shift valve (102) returns to the 2nd gear position on the right side and the 9th oil passage (L
9) connects to the fourth oil passage (LD4) via the sixth oil passage (L6) and the second shift valve (102), and the seventh oil passage (Ll) connects to the fifth oil passage (L5) as described above. ) and drain oil from the 3rd speed hydraulic clutch (C3) and the 2nd speed hydraulic clutch (C2).
The gearbox is refueled and shifted down from the third gear to the second gear, thus making it possible to obtain the shift characteristics as shown in the fourth diagram. Fig. 4 TeX+, x2, and X3 are each in 1st gear →
2nd speed, 2nd-3rd speed, 3rd-4th speed shift up characteristic line,
Y7, Y2, and Y3 are respectively 2nd speed → 1st speed, 3rd speed → 2nd speed, and 4th speed.
The downshift characteristic line from speed to third speed is shown.

In the drawing, (+51 is a regulator valve that regulates the hydraulic pressure supplied from the hydraulic source (8) to a constant line pressure, (!0 is a modulator valve provided on the upstream side of the first throttle valve (141), (
At) (A2) (A3) (A4) indicates an accumulator installed to buffer sudden pressure changes during oil supply and discharge of each hydraulic clutch (C1) (C2) (C3) (C4). Accumulator for 4th speed (A2) (
A3) Apply throttle pressure corresponding to the throttle opening from the second throttle valve (142) to (A4) as back pressure, and press the second oil passage (L2) to the right opening side with the throttle pressure. A pressure reducing valve (+7) is used to reduce the supply pressure to the downstream side of the second oil passage (L2) in the low throttle opening range. In addition, the pressure reducing valve (+7)
is known from Japanese Patent Laid-Open No. 59-168750, and detailed explanation thereof will be omitted.

The first to third oil drain passages (LDI) (LD2) (L
D3) includes oil drain control valves (181) (182) (
183), the pressure drop characteristic of the hydraulic pressure of the disengaging side hydraulic clutch is set to have a speed difference depending on the rise of the hydraulic pressure of the engaging side hydraulic clutch, thereby preventing engine stall due to engine racing or excessive co-engagement. This allows for smooth gear shifting without causing any friction. In addition, 4-speed hydraulic clutch (C4)
The third oil drain control valve (183) interposed in the third drain path (LD3) corresponding to The hydraulic clutches (C3 and C2) of 3rd and 2nd speeds are pushed toward the opening side by the hydraulic pressure, and the third oil drain control valve (183) and the first hydraulic clutch (C2) corresponding to the 2nd speed hydraulic clutch (C2) are The first oil drain control valve (181) installed in the oil drain path (LDI) is connected to the hydraulic pressure of the 4-speed hydraulic clutch (C4) on the releasing side and the hydraulic pressure of the 2-speed hydraulic clutch (C2), respectively.
A known differential pressure-responsive valve that is pressed toward the closing side by the hydraulic pressure of It was constructed as a control valve (see Japanese Patent Laid-Open No. 81-82051).

In addition, when downshifting in the low throttle opening range, a smoother gear shift is achieved by quickly lowering the oil pressure of the hydraulic clutch on the releasing side.
D4), the fourth drain oil control valve (18a) is opened in the low opening range.
) and the third oil drain path (LD3) are connected to the third oil drain path control valve (1).
83) which is opened in the low opening range in parallel with the fifth drain oil control valve (
186).

Note that the fourth and fifth drain oil control valves (18a) (18s) are the second throttle valve (142) and the first throttle valve (14), respectively.
+) consists of a plunger that responds to the throttle interlock lever (14a).

Also, the first shift valve (10a) inputs the governor pressure to the third shift valve (10a).
A first shift control valve (191) that is pushed to the left side by the hydraulic pressure of a second-speed hydraulic clutch (C2) is installed in the second oil passage (L12), as known from Japanese Patent Application Laid-Open No. 81-233248. When shifting up from 2nd to 4th gear, the input of governor pressure to the third shift valve (102) is cut off until the oil pressure of the 2nd gear hydraulic clutch (C2) drops to a predetermined value, and the third shift is performed. The valve (103) is held at the 3rd speed position so that a smooth upshift from 2nd speed to 4th speed can be performed without causing the engine to rev up.

Further, when the second shift valve (102) is in the 3rd speed position, the throttle pressure is applied to the 13th oil passage (Ll3) that inputs the throttle pressure into the annular groove (10za) on the left side of the valve (102). The second shift control valve (
192), the second shift control valve (192) is opened in the high throttle opening range, and the annular groove (192) is opened.
The throttle pressure is input to the second shift valve (10za) in the third gear position by making the land diameter on the right side of the annular groove (lo2a) slightly larger than the land diameter on the left side.
2), in the high opening range, a pressing force is applied to the 2nd gear position by the throttle pressure input to the annular groove (10za), and hysteresis of upshifting and downshifting of 2nd and 3rd gears is applied. is set smaller in the high opening range than in the lower range, and kickdown from 4th gear to 2nd gear and from 3rd gear to 2nd gear can be achieved even in relatively high vehicle speed ranges, improving drivability. Ta.

In the "03" range of the manual valve (9), the first oil passage (Ll) is connected to the second oil passage (L2) as described above, but the 14th oil passage (Ll4) on the output side of the governor valve (13) is connected to the second oil passage (L2). ) and the twelfth oil passage (L12) are cut off, and the third shift valve (
103), the third shift valve (10a) is held at the 3rd speed position, and automatic gear shifting from 1st to 3rd speeds is performed.

By the way, on the inflow side of the first shift valve (1(h), apart from the second oil passage (L2), there is a
The 15th oil passage (L5) communicates with the 5th oil passage (L5) at the 1st speed position.
A control valve a is provided to connect the 15th oil passage (Ll5) and the 4th oil passage (L4) connected to the 1st speed hydraulic clutch (C1) to the 3rd oil passage (L3). Connect from rNJ range of manual valve (9) to rD4J r
When switching to the D3J range, the 2nd speed hydraulic clutch (C2) is first supplied with oil before the 1st speed hydraulic clutch (C1).

To explain this in detail, the control valve aδ communicates the third oil passage (L8) and the fifteenth oil passage (Ll5) via the first annular groove (12a), as shown in FIG. 1st position on the right (
position shown), the third Ura road (L3) and the fourth oil road (L4)
and a second position on the left side which communicates with the oil drain port (12c) via the second annular groove (12b) and communicates the 15th oil passage (Ll5) with the oil drain port (12c) via the first annular groove (12a). The oil chamber (12d) at the right end of the control valve
The pilot oil passage (L8) is branched from the eighth oil passage (L8).
a) to the hydraulic pressure of the second-speed hydraulic clutch (C2) (hereinafter referred to as 2).
When the second speed pressure becomes equal to or higher than the predetermined pressure Ps, the control valve ■ is switched from the first position to the second position against the left end spring (12e). . In this embodiment, the land diameter on the left side of the second annular groove (12b) is formed larger than the land diameter on the right side, and the second annular groove (12b)
starts to communicate with the third oil passage (L3), the second annular groove (
The control valve (121) is instantaneously switched to the second position by the hydraulic pressure according to the difference in pressure receiving areas between the left and right sides of the valve (12b), and is maintained at the second position even if the second speed pressure decreases thereafter.

Thus, when starting by switching the manual valve (9) to the rDd rD3J range, first the 3rd oil path (L3) → 15th oil path (Ll5) → 5th oil path (L5) → 7th oil path ( L
7) → 2nd speed hydraulic clutch (C
2) is refueled, the 2nd speed pressure rises as shown in Figure 5,
A relatively low torque is transmitted to the driving wheels (4) through the 2nd speed transmission system (G2), and then when the 2nd speed pressure rises to the predetermined pressure Ps, the control valve (+21) switches to the second position. As a result, the oil in the 2nd gear hydraulic clutch (C2) is discharged from the oil drain port (12c), and the 2nd gear pressure decreases, and the 1st gear pressure decreases.
The oil pressure (hereinafter referred to as 1st speed pressure) of the high speed hydraulic clutch (C1) rises due to oil supply through the fourth oil passage (L4), and torque transmission via the 1st speed transmission system (G1) is started. , drive wheel (
The drive torque acting on the valve 4) increases in stages, reducing the shock caused when the manual valve (9) is switched.

In addition, between the third oil passage (L3) and the fourth oil passage (L4),
To drain oil from the 1st speed hydraulic clutch (CI), the control valve (
A check valve ■ in parallel with I is installed.

By the way, in the above embodiment, when the control valve ('12) is switched to the second position, the oil discharged from the second-speed hydraulic clutch (C2) and the first
Oil supply to the speed hydraulic clutch (C1) is started at the same time, but the oil supply from the second speed hydraulic clutch (C2) is preceded by the oil supply from the second speed hydraulic clutch (C2).
It is also possible to initiate oil supply to the quick hydraulic clutch (C1), such an embodiment is shown in FIG.

In this model, there are 2
The hydraulic pressure of the third oil passage (L3) is input as the speed pressure, and the left and right land diameters of the second annular groove (12b) are made equal, and as the second speed pressure increases, the control valve (121) moves from the first position to the first position. The land width between the first annular groove (12a) and the second annular groove (12b) is changed to the width of the port connecting the third oil passage (L3). The fourth oil passage (L4) is made narrower in the intermediate area between the first position and the second position.
and the 15th oil passage (Ll5) are both connected to the third oil passage (L3).

According to this, the second speed pressure rises to the predetermined pressure Ps and the control valve ■
Oil supply to the 1st speed hydraulic clutch (CI) is started before reaching the 2nd position, and at the time oil draining from the 2nd speed hydraulic clutch (C2) begins, the 1st speed pressure is as shown in Fig. 7. The first speed transmission system (Gl) is smoothly established without causing the engine to rev up.

In the “2” range of the manual valve (9), the first oil path (Ll
) and the second oil passage (L2) are cut off, and the first oil passage (L2) is disconnected from the first oil passage (L2).
An eighth oil passage (L8) is connected to a branch passage (L18a) branched from a sixteenth oil passage (LlB) communicating with l), and only the second-speed hydraulic clutch (C2) is supplied with oil.

In addition, in the rRJ range of the manual valve (9), the first oil path (
A servo valve (Ll7) connected to the first oil chamber (11a) on the left end at 1°C is connected to the first oil chamber (Ll).
Line pressure is input to the oil chamber (Ila), the servo valve C11) is pushed to the reverse position, the select gear (6) is switched to the reverse side, and the 17th oil passage (Li2) is connected to the servo valve C11) connected to the oil chamber (Ila). 18th through the shaft hole (11b) of the valve (Iv)
It is connected to the oil path (L l 8 ). The 18th oil passage (L
lg) is connected to the 11th oil passage (Lll) connected to the 4th speed hydraulic clutch (C4) in the rRJ range of the manual valve (9), thus supplying oil to the 4th speed hydraulic clutch (C4) and controlling the selector gear. (6) Switching to the reverse side establishes the reverse transmission system (GR).

In the figure, ■ indicates the first servo control valve installed in the 17th oil passage (Li2), and the control valve ■ is pushed to the left closed position by the governor pressure input through the 14th oil passage (L12). However, if the manual valve (9) is switched to the rRJ range while the vehicle is moving forward at a predetermined speed or higher, the control valve
a) is switched to the closed position to prevent input of line pressure to the first oil chamber (11a) of the servo valve Gt;
The locking member (llc) holds the servo valve av in the forward position to prevent the reverse transmission system (GR) from being engaged or raised. In addition, the manual valve (9) is rD4J rDsJ
When switching to the r2J range, the control valve 0 is
The line pressure input through the 6th oil passage (Llg) ensures that the vehicle is switched to the right open position, and during reversing, the line pressure input through the 18th oil passage (Llg) maintains the vehicle speed at or above the specified vehicle speed. The control valve (1) can be held in the open position even when the

Set the manual valve (9) to "D4" and "D3" from the fRJ range.
When switching to the "2" range, the servo valve (+1) has a second oil chamber (11a) formed opposite to the first oil chamber (11a).
11d) through the 19th oil passage (Li2) branched from the 18th oil passage (LlB) to push the servo valve 0v to the forward position.
A second servo control valve (■) is interposed in Uraji (Li2), and the control valve (■) is pushed to the left open position by the 1st speed pressure and 2nd speed pressure, and rD4J is changed from the rRJ range of the manual valve (9). rDs
After switching to the J r2J range, the control valve ■ remains in the closed position (the position shown) until the 1st speed pressure and 2nd speed pressure rise to the predetermined values.
The line pressure is prevented from being input to the second oil chamber (11d), the servo valve (IT) is held in the reverse position by the locking means (11c), and the 1st speed pressure and 2nd speed pressure are maintained at predetermined values. When the above condition is reached, the control valve (1) is switched to the open position against the left end spring (C22a), line pressure is input to the second oil chamber (11d), and the servo valve (1) is switched to the forward position. Thus, with the accelerator pedal depressed, the manual valve (9) can be changed from rRJ range to rD4J rD.
Even when switching to the sJ "2" range, at the time of switching the servo valve aυ, the positive pressure is generated through the transmission system (Gl) (G2) of the 1st and 2nd speeds due to the rise in the 1st and 2nd speed pressures to the specified values. The rotation of the output shaft (lb) in the reverse direction is stopped by the torque transmission in the reverse direction, and the selector gear (6) and the counter gear (G4a) of the 4-speed transmission system (G4) undergo a large relative rotation. Both gears (6) (G4
A) Wear of the meshing part is prevented.

By the way, if the second servo control valve (2) is locked in the closed position due to foreign matter, etc., or even if the control valve (2) is switched to the open position, the servo valve (ID) is locked in the reverse position, the manual valve ( 9) from rRJ range to D4J r
DsJ r2 Even if you switch to J range, the selector gear (
6) remains on the reverse side, and when the 4th speed hydraulic clutch (C4) is refueled, the reverse transmission system (OR) is established.
The 20th oil passage (L20) connected to the oil chamber (102b) at the left end of the second shift valve (102) is connected to the upstream portion of the 19th oil passage (Li2) at the closed position of the second servo control valve (■), Further, in the reverse position of the servo valve (11), the second oil chamber (11d)
A 21st valve that communicates with the valve a1 through the notch groove (11e) of the valve a1.
An oil passage (L21) is provided so that the 21st oil passage (L21) and the 20th oil passage (L20) are connected when the second servo control valve (■) is in the open position, and when the above abnormality occurs, The 20th oil passage (
Line pressure is input through the second shift valve (L20) to hold the second shift valve (102) in the second gear position on the right, thereby preventing oil supply to the fourth gear hydraulic clutch (C4).

In addition, the second servo control valve
The third oil drain control valve (LD3) is connected to the third oil drain passage (LD3) corresponding to the 4th speed hydraulic clutch (C4) so that the line pressure input via the line pressure input to the closed position ensures the return to the closed position.
183) is interposed in parallel with the sixth oil drain control valve (186) which is pushed to the right open position by the hydraulic pressure of the 20th oil passage (L20), and the rD4J r
D3J r2 At the beginning of switching to the J range, the line pressure input through the second servo control valve ■, which is in the closed position, and the 20th oil passage (L20) causes the 6th drain oil control valve (18a) to be activated.
The valve was opened to allow the oil from the 4-speed hydraulic clutch (C4) to be drained quickly.

- In the drawing, a clutch is provided to mechanically connect the input side and output side of the fluid torque converter (3), and ■ indicates a hydraulic circuit for controlling the clutch ■, and the circuit [phase]
includes a switching valve (■) for controlling the connection and disconnection of the clutch (2), a first and second on-off valve (■) for switching and controlling the switching valve (■), and control for switching the operating state of the clutch (■) between a direct connection state and a slipping state. A control valve (■) that controls the clutch engagement force in a slipping state and a pressure regulating valve (■) that controls the clutch engagement force in a slipping state are provided. In the high vehicle speed range, the clutch is operated in a direct connection state, and when the 4-speed transmission system (G4) is established, the clutch is operated in the vehicle speed range of 73 line or higher on the high speed side of the Z line. I made it work. In addition, these valves are disclosed in Japanese Unexamined Patent Application Publication No. 61-2
It is not particularly different from those known in No. 78859 and Japanese Unexamined Patent Publication No. 62-513662, and detailed explanation thereof will be omitted.

(Effects of the Invention) As is clear from the above description, according to the invention of claim 1, when the manual valve is switched to the travel range, the control valve remains in the first position until the hydraulic pressure of the high-speed hydraulic engagement element rises to a predetermined pressure. 2 position, the high-speed transmission system reliably transmits torque before the low-speed transmission system even at low temperatures, preventing a sudden rise in the drive torque acting on the drive wheels, and reducing the switching shock. This has the effect of reducing

Further, according to the invention of claim 2, oil supply to the low speed hydraulic engagement element is started prior to draining oil from the high speed hydraulic engagement element,
This has the effect of smoothly establishing a low-speed transmission system following a high-speed 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.
Fig. 4 is a diagram showing the shift characteristic diagram, Fig. 5 is a diagram showing the change characteristics of the 1st speed pressure and 2nd speed pressure at the time of starting, and Fig. 6 is an enlarged view of the main part of the hydraulic circuit showing another embodiment. 7 are diagrams showing the change characteristics of the 1st speed pressure and the 2nd speed pressure at the time of starting in this embodiment of the function. (Gl)...1st speed transmission system (low speed transmission system) (G2)...
・2nd speed transmission system (high speed transmission system) (C1)...1st speed hydraulic clutch (low speed hydraulic engagement element) (C2)...2nd speed hydraulic clutch (high speed hydraulic engagement element) (7)... One-way clutch (8)...Hydraulic pressure source (9)...Manual valve (IG...Shift valve one...Control valve (12c)...Oil drain port (L2)...Second oil Road (first oil road) (L3)...
Third oil passage (second oil passage) (L4)...Fourth oil passage (fourth oil passage)
oil passage) (L5)...15th oil passage (third oil passage) outside 3
First name - Medium speed ■ Haruma ■ Yoshii

Claims (1)

[Claims] 1. Hydraulic actuation for a vehicle comprising at least a two-stage transmission system, a low-speed transmission system and a high-speed transmission system, and a one-way clutch that allows over-rotation on the output side intervenes in the low-speed transmission system. A control device for a type transmission, which includes a neutral range in a hydraulic circuit that controls oil supply and drainage to a low-speed hydraulic engagement element that establishes the low-speed transmission system and a high-speed hydraulic engagement element that establishes the high-speed transmission system. A manual valve that can be switched between at least two ranges, i.e., and a travel range, and a shift valve that can be switched between at least two positions, a low speed position and a high speed position,
providing first and second oil passages that are connected to a hydraulic power source when the manual valve is in a travel range, and providing a third oil passage that is connected to the second oil passage via a control valve; A first oil passage is selectively connected to the high-speed hydraulic engagement element at a high-speed position of the shift valve, and a third oil passage is connected to a third oil passage at a low-speed position of the shift valve, and the control valve is connected to a second oil passage at a low-speed position of the shift valve. and a third oil passage, a fourth oil passage that disconnects communication between the two oil passages and connects the second oil passage to the low-speed hydraulic engagement element, and a third oil passage that communicates with the low-speed hydraulic engagement element. The control valve is configured to be freely switchable to a second position connected to an oil drain port, and the control valve is switched to the second position when the hydraulic pressure of the high-speed hydraulic engagement element rises to a predetermined pressure. Control device for hydraulically operated transmissions for vehicles. 2. The control valve is configured to be gradually moved toward the second position as the hydraulic pressure of the high-speed hydraulic engagement element increases;
2. The vehicle according to claim 1, wherein the third oil passage and the fourth oil passage are both communicated with the second oil passage in an intermediate region between the first position and the second position. Control device for hydraulically operated transmission.