JP2016121740A - Hydraulic control device of automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve efficiency in warming-up in a hydraulic control device of an automatic transmission.SOLUTION: In a hydraulic control device of an automatic transmission, a selector valve 35 includes an input port 35c to which a first oil passage L1 is connected, a first output port 35f to which a second oil passage L2 is connected, and a second output port 35g connected to a predetermined portion in the automatic transmission other than an oil cooler 51 through a third oil passage L3. The input port 35c can selectively switch to any one of the first output port 35f and the second output port 35g, according to temperature of working oil in the automatic transmission.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a hydraulic control device for an automatic transmission.

  As a type of hydraulic control device for an automatic transmission, the one shown in Patent Document 1 is known. As shown in FIG. 1 of Patent Document 1, in the hydraulic control device for an automatic transmission, when the oil temperature of the hydraulic oil is lower than a set temperature T1, the oil cooler bypass valve 27 is opened. The hydraulic oil is bypassed without passing through the oil cooler 25. Thus, for example, when the oil temperature of the hydraulic oil is low, such as immediately after the start of the vehicle, the oil temperature is quickly raised, the oil temperature is suitable for driving the vehicle, and the fuel consumption of the vehicle is improved. It has become.

JP 2007-2111968 A

  In the hydraulic control device for an automatic transmission described in Patent Document 1 described above, when the oil cooler bypass valve 27 is opened, part of the hydraulic oil is bypassed without passing through the oil cooler 25. Since the remaining part of the hydraulic oil is supplied to the oil cooler 25 and cooled, there is a problem that the efficiency during warm-up is not good.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to further improve the efficiency during warm-up in a hydraulic control device for an automatic transmission.

  In order to solve the above-described problem, an invention of a hydraulic control device for an automatic transmission according to claim 1 includes a torque converter including an inlet portion into which hydraulic oil flows and an outlet portion from which hydraulic oil flows out, a torque converter, A hydraulic control device for an automatic transmission, comprising: a switching valve connected via a first oil passage; and an oil cooler connected via a switching valve and a second oil passage. An input port to which one oil passage is connected, a first output port to which a second oil passage is connected, and a second output connected to a predetermined part in the automatic transmission other than the oil cooler via a third oil passage And the input port can be selectively switched to either the first output port or the second output port according to the temperature of the hydraulic oil in the automatic transmission.

  According to this, the hydraulic oil warmed by the torque converter can be selectively supplied to a predetermined part in the oil cooler or the automatic transmission according to switching of the switching valve. That is, at the time of warming up (when the operating oil is at a low temperature), the operating oil warmed by the torque converter is not supplied to the oil cooler and is not cooled, but is supplied to a predetermined part in the automatic transmission that needs to be warmed up. As a result, the entire automatic transmission can be warmed up efficiently and quickly.

1 is a diagram illustrating a first embodiment of a hydraulic control device for an automatic transmission according to the present invention. FIG. It is a figure which shows the principal part (a switching valve, an oil cooler, an oil pump) of the hydraulic control apparatus of the automatic transmission shown in FIG. It is a figure which shows the principal part (a switching valve, an oil cooler, a friction engagement member (automatic transmission)) of the hydraulic control apparatus of the automatic transmission shown in FIG. It is a flowchart of the control program performed with the control apparatus shown in FIG. It is a figure which shows 2nd embodiment of the hydraulic control apparatus of the automatic transmission by this invention. It is a figure which shows 3rd embodiment of the hydraulic control apparatus of the automatic transmission by this invention. It is a figure which shows the principal part (a switching valve, an oil cooler, an oil pump, a friction engagement member) of the hydraulic control apparatus of the automatic transmission shown in FIG.

-First embodiment-
Hereinafter, a first embodiment of a hydraulic control device for an automatic transmission according to the present invention will be described. The hydraulic control device for an automatic transmission according to the present embodiment is a vehicle that includes an engine (not shown) that is a driving power source, a torque converter 10, an automatic transmission 20, a hydraulic control circuit 30, a control device 40, and the like. Applied. The hydraulic control device for the automatic transmission includes a torque converter 10, an automatic transmission 20, a hydraulic control circuit 30, a control device 40, and the like.

  A crankshaft (not shown), which is an output shaft of the engine, is connected to the torque converter 10, and the engine output is distributed from the torque converter 10 to the left and right drive wheels (not shown) via the automatic transmission 20 and the like. Is done. Each part of the engine, the torque converter 10, the automatic transmission 20, and the control device 40 will be described below.

  As shown in FIG. 1, the torque converter 10 includes a pump impeller 11 on the input shaft side, a turbine runner 12 on the output shaft side, a stator 13 that expresses a torque amplification function, and a one-way clutch 14. Between the turbine runner 12 and the turbine runner 12 through the fluid.

The torque converter 10 is provided with a lockup clutch 15 that directly connects the input side and the output side of the torque converter 10. As shown in FIG. 1, the lockup clutch 15 has a differential pressure (lockup differential pressure) ΔP (ΔP = in the lockup oil chamber 16) between the hydraulic pressure in the lockup oil chamber 16 and the hydraulic pressure in the torque converter oil chamber 17. (Hydraulic pressure P _ON -hydraulic pressure P _OFF in the torque converter oil chamber 17) is a hydraulic friction clutch in which the clutch portion 15a is frictionally engaged. The lock-up clutch 15 is fully engaged / half-engaged (engaged in a slip state) or released by controlling the differential pressure ΔP.

  By completely engaging the lockup clutch 15, the pump impeller 11 and the turbine runner 12 rotate integrally. Further, by engaging the lockup clutch 15 in a predetermined slip state (half-engaged state), the turbine runner 12 rotates following the pump impeller 11 with a predetermined slip amount during driving. On the other hand, the lockup clutch 15 is released by setting the lockup differential pressure ΔP to be negative.

  As shown in FIG. 3, the automatic transmission 20 includes a double pinion type first planetary gear device 21, a single pinion type second planetary gear device 22, and a single pinion type third planetary gear device 23. . The first planetary gear device 21 includes three rotating elements, that is, a sun gear S1, a carrier CA1, and a ring gear R1. The second planetary gear device 22 includes three rotation elements, that is, a sun gear S2, a carrier CA2, and a ring gear R2. The third planetary gear device 23 includes three rotating elements, a sun gear S3, a carrier CA3, and a ring gear R3.

  Sun gear S1 is selectively coupled to carrier CA2 via first clutch C1. Ring gear R1 is selectively coupled to ring gear R2 via second clutch C2. The ring gear R2 is fixed to the housing 20a via the first brake B1. Carrier CA2 and ring gear R3 are fixed to housing 20a via second brake B2. The first and second clutches C1 and C2 and the first and second brakes B1 and B2 are friction engagement members 57 that are engaged and released by supplying hydraulic oil.

Next, the hydraulic control circuit 30 will be described with reference to FIG. FIG. 1 shows only the main part of the hydraulic control circuit of the torque converter 10 with the lockup clutch 15.
First, the hydraulic oil pump 53 occurs is the line pressure P _L1 and is generated pressure regulated by the primary regulator valve (not shown), the secondary pressure P by the secondary regulator valve (not shown) the line pressure P _L1 as source pressure _SEC is regulated. The line pressure P _L1 generated by the primary regulator valve is supplied pressure is regulated to a constant pressure P _M at the modulator valve to the linear solenoid valve 31 and solenoid valve 32.

The linear solenoid valve 31 outputs the control pressure P _SLU to the lockup control valve 34 according to the current value determined by the duty signal (duty value) transmitted from the control device 40. The solenoid valve 32 outputs the control pressure _PSL to the lockup relay valve 33 according to the current value determined by the duty signal (duty value) transmitted from the control device 40.

The lockup relay valve 33 is a valve for switching the engagement or disengagement of the lockup clutch 15 according to the control pressure _PSL from the solenoid valve 32.
The lockup relay valve 33 is provided with a spool valve element 33a that is movable along the axial direction. A compression coil spring 33b is disposed on one end side (the lower end side in FIG. 1) of the spool valve element 33a, and an end (upper end part) opposite to the compression coil spring 33b across the spool valve element 33a. An oil chamber 33c to which the control pressure _PSL from the solenoid valve 32 is supplied is provided.

The lockup relay valve 33 is connected to the first and second input ports 33d and 33e to which the secondary pressure _PSEC from the secondary regulator valve is input, and to the lockup oil chamber 16 of the torque converter 10. The engagement side port 33f to which the path 16a is connected, the release side port 33g to which the torque converter inlet port 17a (corresponding to the “inlet part into which hydraulic oil flows”) communicating with the torque converter oil chamber 17 is connected, the torque converter oil A first discharge port 33h to which a torque converter outlet port 17b communicating with the chamber 17 is connected; second to fourth discharge ports 33i, 33j, 33k for discharging hydraulic oil; first, second and third bypass ports 33l; 33m, 33n, etc. are provided.
Incidentally, the second input port 33e, the secondary pressure _{P SEC} is input is reduced by the orifice 33o. The fourth discharge port 33k communicates with an input port 35c of a switching valve 35 (described later) through a first oil passage L1.

  In the lockup relay valve 33 shown in FIG. 1, when the position of the spool valve element 33a is on the left side with respect to the center line, the lockup relay valve 33 is on and the lockup clutch 15 is engaged. . When the position of the spool valve element 33a is on the right side with respect to the center line, the lockup relay valve 33 is in an off state, and the lockup clutch 15 is released.

The lock-up control valve 34 adjusts the differential pressure ΔP when the lock-up clutch 15 is in the engaged state by the lock-up relay valve 33 to change the operating state of the lock-up clutch 15 to the slip state including the released state. It is a valve that switches in the range from to lock-up on.
The lock-up control valve 34 includes a spool valve element 34a and a compression coil spring 34b that applies thrust toward the spool valve element 34a toward the slip (SLIP) side position. Further, the lock-up control valve 34, the oil chamber 34c for receiving the hydraulic pressure _{P ON} in the lock-up oil chamber 16 of the torque converter 10 to bias toward the spool 34a to the SLIP side position, the spool valve element 34a In order to urge the valve to the fully engaged (ON) side, the oil chamber 34d and the spool valve element 34a for receiving the hydraulic pressure P _OFF in the torque converter oil chamber 17 of the torque converter 10 are urged toward the ON side position. For this purpose, an oil chamber 34e for receiving the control pressure P _SLU , an input port 34f to which the secondary pressure P _SEC from the secondary regulator valve is supplied, a control port 34g, a discharge port 34h for discharging the hydraulic oil, and the like are provided.

In the lock-up control valve 34 shown in FIG. 1, when the position of the spool valve element 34a is on the left side of the center line, the fully engaged state (ON) is shown, and the position of the spool valve element 34a is at the center line. On the other hand, when it is on the right side, it indicates a slip state (including a fully released state). Here, when the control pressure _PSLU is not supplied to the lock-up control valve 34 and the spool valve element 34a is positioned at the lower end in FIG. 1 by the elastic force of the compression coil spring 34b, the “completely released state (OFF)”. It becomes the state of.

The case where the lockup clutch 15 is controlled to be locked up in the hydraulic control circuit 30 described above will be described.
In the lock-up relay valve 33, when the control pressure _{P SL} spool valve element 33a by the thrust of the supplied not spring 33a is biased to the release (OFF) side position to the oil chamber 33c, it is supplied to the first input port 33d The secondary pressure _PSEC is supplied from the release side port 33g to the torque converter oil chamber 17 through the torque converter inlet port 17a. At the same time, the hydraulic oil discharged through the torque converter oil chamber 17 through the torque converter outlet port 17b and discharged to the first discharge port 33h is supplied from the fourth discharge port 33k to the switching valve 35. The hydraulic oil in the lockup oil chamber 16 passes through the lockup clutch oil passage 16a, and the hydraulic oil discharged to the engagement side port 33f is discharged from the third discharge port 33j to the oil pan. At this time, the hydraulic pressure _{P OFF} of the torque converter oil chamber 17 is a secondary pressure _{P SEC,} pressure _{P ON} the lock-up oil chamber 16 is zero (atmospheric pressure). That is, since the hydraulic pressure _{P OFF} of the torque converter oil chamber 17 becomes higher than the hydraulic pressure _{P ON} the lock-up oil chamber 16, the pressure difference ΔP is negative. Thus, the lockup clutch 15 is completely released and is locked off.

Next, the case where the lockup clutch 15 is controlled from the slip state including the released state to the lockup on will be described.
In the lock-up relay valve 33, the control pressure P when _SL is supplied to the oil chamber 33c spool 33a is urged to the engaged (ON) side position, the secondary pressure P supplied to the first input port 33d After passing through the first bypass port 33l, the _SEC is decompressed by the orifice 33p, passes through the second bypass port 33m and the release port 33g, and then supplied to the torque converter oil chamber 17 through the torque converter inlet port 17a. The constant pressure reduction hydraulic pressure P _SEC 2 supplied to the torque converter oil chamber 17 becomes the hydraulic pressure P _OFF .
At the same time, the lockup oil chamber 16 communicates with the control port 34g of the lockup control valve 34 through the lockup clutch oil passage 16a, the engagement side port 33f, and the third bypass port 33n. Then, the hydraulic pressure P _ON the lock-up oil chamber 16 is adjusted by the lock-up control valve 34 (i.e., the differential pressure ΔP is adjusted by the lock-up control valve 34), the operating state of the lock-up clutch 15 is slip state To lock-up on.

Specifically, when the spool valve element 33a of the lockup relay valve 33 is biased to the engagement side position (that is, when the lockup clutch 15 is switched to the engagement side state), the lockup is performed. In the control valve 34, the control pressure _PSLU for urging the spool valve element 34a to the fully engaged (ON) side position is not supplied to the oil chamber 34e, and the spool valve element 34a is caused by the elastic force of the compression coil spring 34b. Is placed at the slip (SLIP) side position, the secondary pressure P _SEC supplied to the input port 34f is regulated according to the control pressure P _SLU and the third bypass of the lockup relay valve 33 from the control port 34g. The oil is supplied from the engagement side port 33f to the lockup oil chamber 16 through the lockup clutch oil passage 16a via the port 33n. In this state, the differential pressure ΔP is controlled according to the control pressure _PSLU to control the slip state (including the released state) of the lockup clutch 15. That is, the hydraulic pressure _{P OFF} of the torque converter oil chamber 17 is a secondary pressure _{P SEC} is depressurized vacuum pressure _{P SEC} 2 (<secondary pressure _{P SEC).} On the other hand, the hydraulic pressure _{P ON} the lock-up oil chamber 16 is a hydraulic secondary pressure _{P SEC} is pressure regulated in accordance with the control pressure _{P SLU,} pressure adjusted between the vacuum pressure _{P SEC} 2 until the secondary pressure _{P SEC} ing. In this state, the differential pressure ΔP is controlled by the control pressure _PSLU to control the slip state (including the released state) of the lockup clutch 25.

Further, when the spool valve element 33a of the lockup relay valve 33 is urged to the engagement side position, the spool valve element 34a is urged to the complete engagement (ON) position in the lockup control valve 34. When the control pressure P _SLU is supplied to the oil chamber 34e, the secondary pressure P _SEC is supplied from the input port 34f to the torque converter oil chamber 17. At this time, the hydraulic pressure _{P OFF} of the torque converter oil chamber 17 are vacuum pressure _{P SEC} 2, hydraulic pressure _{P ON} the lock-up oil chamber 16 is a secondary pressure _{P SEC} is the maximum pressure that can be pressure regulated. That is, the differential pressure ΔP is maximized and the lockup clutch 15 is fully engaged.

  A relief valve 36 is connected to the first and second bypass ports 33l and 33m and the oil chamber 34d. The relief valve 36 communicates with the torque converter oil chamber 17 in the torque converter 10 when the lockup relay valve 33 is urged toward the engagement side, and the torque converter oil is adjusted to a pressure corresponding to the load of the spring 36s. The hydraulic pressure in the chamber 17 is controlled.

Switching valve 35 is controlled switching based on the received control pressure P _SLU from pressure P _SL and the linear solenoid valve 31 is selectively configured to be able to discharge destination of the hydraulic oil from the solenoid valve 32. The switching valve 35 includes a spool valve element 35a and a compression coil spring 35b that applies thrust toward the spool valve element 35a toward the first position. The switching valve 35 includes an input port 35c to which hydraulic oil is supplied from the first oil passage L1, an oil chamber 35d that receives the control pressure _PSLU to urge the spool valve element 35a toward the first position, an oil chamber 35e that receives the control pressure P _SL to bias toward the spool 35a to the second position, the first output port 35f that is connected to the second oil passage L2 which is connected to the oil cooler 51 And a second output port 35g connected to a third oil passage L3 connected to a predetermined portion 52 of the automatic transmission 20.

  The switching valve 35 is connected to the torque converter 10 via the first oil passage L1, and is connected to the oil cooler 51 via the second oil passage L2. The first oil passage L <b> 1 and the second oil passage L <b> 2 are oil passages that connect the torque converter 10 and the oil cooler 51, and supply hydraulic oil flowing out from the torque converter outlet port 17 b to the oil cooler 51. In the oil cooler 51, the hydraulic oil flowing out from the torque converter 10 is cooled. The input port 35c can be selectively switched to either the first output port 35f or the second output port 35g according to the temperature of the hydraulic oil in the automatic transmission 20 (described later). .

  In FIG. 1, when the spool valve element 35a is on the left side with respect to the center line, the switching valve 35 is in the first position, and when the spool valve element 35a is on the right side with respect to the center line, the switching valve 35 is shown. Is in the second position. In the first position, the input port 35c communicates with the first output port 35f, and in the second position, the input port 35c communicates with the second output port 35.

  Between the 1st output port 35f and the 2nd output port 35g, the 4th oil path L4 which connects both ports 35f and 35g is provided. The fourth oil passage L4 connects between the portion of the second oil passage L2 and the portion of the third oil passage L3. The fourth oil passage L4 is provided with an orifice 54 and / or a check valve 55. The orifice 54 restricts the flow rate (flow rate per unit time) of the hydraulic oil flowing through the fourth oil passage L4. The check valve 55 restricts the flow from the first output port 35f to the second output port 35g but allows the flow in the opposite direction.

  The predetermined part 52 of the automatic transmission 20 is an oil pump 53 or a friction engagement member 57 as shown in FIGS. As shown in FIG. 2, the oil pump 53 sucks the hydraulic oil accumulated in the oil pan 54 through the strainer 55 and sends it to each portion 56 (for example, each planetary gear device) in the automatic transmission 20. The third oil passage L3 is connected to the suction port of the oil pump 53. The third oil passage L3 is provided with a check valve and an orifice that allow the flow to the predetermined portion 52 but restrict the flow to the switching valve 35.

  Further, an electromagnetic valve or a thermal valve may be provided on the strainer 55 side of the oil passage between the oil pump 53 and the strainer 55 from the connection point with the third oil passage L3. When the temperature of the hydraulic oil is equal to or lower than a predetermined temperature, the electromagnetic valve or the thermal valve may be closed so that the hydraulic oil from the switching valve 35 is supplied directly to the oil pump 53. When the temperature of the hydraulic oil is higher than a predetermined temperature, the electromagnetic valve or the thermal valve is opened so that the hydraulic oil from the switching valve 35 is supplied not only to the oil pump 53 but also to the oil pan 54. The electromagnetic valve is a valve that is opened and closed according to an opening / closing instruction of the control device 40. The thermal valve is a valve that is opened and closed according to the ambient temperature and the temperature of the hydraulic oil.

FIG. 4 illustrates the operation of the control device 40 that controls the control pressure P _SL of the solenoid valve 32 that controls the lock-up relay valve 33 and the control pressure P _SLU of the linear solenoid valve 31 that controls the operation of the switching valve 35. It is a flowchart for.
The control device 40 acquires the oil temperature of the automatic transmission (AT) from the temperature sensor 41 in step S102. The temperature sensor 41 is provided in a part (for example, a valve body (not shown)) where the hydraulic oil is present (flows) in the automatic transmission 20, and detects the temperature of the hydraulic oil at that location to the control device 40. Output.
Further, in order to control the lockup clutch 15, the control device 40 acquires the accelerator opening as the vehicle speed and the accelerator operation amount of the driver from each detection means (not shown).

In step S104, the control device 40 determines whether or not the control condition for the lockup clutch 15 is established based on the previously acquired vehicle speed and accelerator opening. If the control device 40 determines that the control conditions for the lockup clutch 15 are satisfied, the control device 40 advances the program to step S110 and turns on the solenoid valve 32. Therefore, since the control pressure _PSL is input to the oil chamber 33c of the lockup relay valve 33, the lockup relay valve 33 is shifted to the ON side.
Subsequently, when the control device 40 controls the linear solenoid valve 31 (for example, by PWM control) in step S111, the control pressure P _SLU is input to the oil chamber 34e of the lockup control valve 34, and the lockup clutch 15 Hydraulic pressure is controlled. Although the control pressure P _SLU is also supplied to the oil chamber 35d of the switching valve 35, the control pressure P _SL of the solenoid valve 32 is input to the oil chamber 35e of the switching valve 35 in step S110. The valve 35 is held in the state shown on the left side in FIG. 1 by the urging force of the compression coil spring 35g.

On the other hand, if control device 40 determines that the control condition for lockup clutch 15 is not satisfied (determined as “NO” in step S104), the program proceeds to step S105, and the AT oil temperature is preset. Compare with the judgment temperature. When the AT oil temperature is lower than the determination temperature, the control device 40 advances the program to step S106 and turns off the solenoid valve 32. That is, since the control pressure P _SL of the solenoid valve 32 is not input to the oil chamber 33c of the lock-up relay valve 33, lock-up relay valve 33 is shifted to OFF by the urging force of the compression coil spring 35 g. Thus, the torque converter outlet port 17b is connected to the input port 35c of the switching valve 35 via the first oil passage L1, the first discharge port 33h, the fourth discharge port 33k, and the first oil passage L1.

Subsequently, the control device 40 turns on the linear solenoid valve 31 in step S107. Thus, the control pressure _PSLU from the linear solenoid valve 31 is input to the oil chamber 34e of the lockup control valve 34 and also to the oil chamber 35d of the switching valve 35. Since the step S106 the control pressure _{P SL} of the solenoid valve 32 is not input to the oil chamber 35e of the switching valve 35, switching valve 35, against the urging force of the compression coil spring 35g on the side (in FIG. 1 To the right of the figure). Thereby, in the switching valve 35, the input port 35c and the second output port 35g (the predetermined portion 52 of the automatic transmission 20) are communicated, and the torque converter outlet port 17b is connected to the predetermined portion 52 of the automatic transmission 20. . Therefore, when the hydraulic oil temperature is relatively low, the hydraulic oil in the torque converter 10 is not supplied to the oil cooler 51 but is supplied to the predetermined portion 52 of the automatic transmission 20, so that the oil temperature rises quickly. The determination temperature is set to normal temperature (for example, 20 ° C.).

When the AT oil temperature is equal to or higher than the determination temperature (“YES” in step S105), control device 40 advances the program to step S108 and turns off solenoid valve 32 as in step S106 described above. The lockup relay valve 33 is turned off.
Subsequently, the control device 40 turns off the linear solenoid valve 31 in step S109. Thus, the control pressure _PSLU from the linear solenoid valve 31 is not input to the oil chamber 34e of the lockup control valve 34 and is not input to the oil chamber 35d of the switching valve 35. Therefore, the switching valve 35 is shifted to the left side in FIG. 1 by the urging force of the compression coil spring 35g. Thereby, since the input port 35c and the first output port 35f are communicated with each other in the switching valve 35, the hydraulic oil in the torque converter 10 is supplied to the oil cooler 51 and reliably cooled.

Further, the operation of the above-described automatic transmission hydraulic control device will be described.
1) First, the normal operation (at room temperature) will be described. When the vehicle starts running from a stopped state, the lockup clutch 15 is in an off (released) state. In this case, the solenoid valve 32 is off (a state of not outputting a control pressure P _SL), since the linear solenoid valve 31 is also in the OFF state (state of not outputting a control pressure P _SLU), the switching valve 35 is a spool valve element 35a is in the first position. That is, each control pressure is not applied to the oil chamber 35d and the oil chamber 35e, and the spool valve element 35a is in the first position by the urging force of the compression coil spring 35b. Further, the instruction from the solenoid valve 32 is OFF, and the lockup relay valve 33 is OFF. Therefore, the torque converter outlet port 17b is connected to the input port 35c of the switching valve 35 via the first oil passage L1 via the first discharge port 33h and the fourth discharge port 33k. Thus, since the torque converter outlet port 17b is connected to the oil cooler 51, the hydraulic oil in the torque converter 10 is supplied to the oil cooler 51 and cooled.

  On the other hand, when the lockup clutch 15 is off, the hydraulic oil in the torque converter 10 becomes relatively hot due to the stirring by the pump impeller 11 and the turbine runner 12. The high temperature hydraulic oil in the torque converter 10 is supplied to the oil cooler 51 and cooled.

  At this time, since the check valve 55 is provided in the fourth oil passage L4 connecting the first discharge port 35f and the second discharge port 35g, the hydraulic oil in the torque converter 10 having a high temperature is automatically transmitted to the automatic transmission. It is possible to reliably suppress supply (outflow) to the 20 predetermined portions 52. As a result, since all the operating oil in the torque converter 10 having a high temperature is supplied to the oil cooler 51, it is possible to suppress a decrease in cooling efficiency.

2) The operation when the vehicle speed increases will be described. When the vehicle speed increases, the lock-up clutch 15 is turned on (completely engaged) in order to synchronize engine rotation and turbine rotation in order to improve fuel efficiency. In this case, the solenoid valve 32 is in the ON state (state of outputting a control pressure P _SL), since the linear solenoid valve 31 is also in an ON state (state of outputting a control pressure P _SLU), the lock-up relay valve 33 is turned on The lockup control valve 34 is also in the on state. Therefore, as described above, the hydraulic pressure _{P OFF} of the torque converter oil chamber 17 are vacuum pressure _{P SEC} 2, hydraulic pressure _{P ON} the lock-up oil chamber 16 is a secondary pressure _{P SEC} is the maximum pressure that can be pressure regulated. That is, the differential pressure ΔP is maximized and the lockup clutch 15 is fully engaged.
The torque converter outlet port 17b is connected to the oil pan 54 via the first discharge port 33h and the second discharge port 33i. On the other hand, when the lock-up clutch 15 is on, the engine rotation and the turbine rotation are synchronized, so that the hydraulic oil in the torque converter 10 has a temperature rise caused by agitation by the pump impeller 11 and the turbine runner 12. Therefore, it is not necessary to cool the oil cooler 51. Therefore, the hydraulic oil in the torque converter 10 having a relatively low temperature is discharged to the oil pan 54.

3) The operation when the oil temperature of the automatic transmission 20 is in a low temperature state will be described.
When the vehicle is stopped, the solenoid valve 32 is turned off (a state where the control pressure _PSL is not output), and the linear solenoid valve 31 is turned on (a state where the control pressure _PSLU is output). In this case, the switching valve 35 is in a state where the spool valve element 35a is in the second position. That is, since the control pressure P _SLU is applied to the oil chamber 35d and the control pressure P _SL is not applied to the oil chamber 35e, the spool valve element 35a is controlled by the control pressure P _SLU that resists the biasing force of the compression coil spring 35b. In the second position. Further, the instruction from the solenoid valve 32 is OFF, and the lockup relay valve 33 is OFF. Therefore, the torque converter outlet port 17b is connected to the input port 35c of the switching valve 35 via the first oil passage L1 via the first discharge port 33h and the fourth discharge port 33k. Thus, the torque converter outlet port 17 b is connected to the predetermined portion 52 of the automatic transmission 20, so that the hydraulic oil in the torque converter 10 is supplied to the predetermined portion 52 of the automatic transmission 20.

  On the other hand, since the solenoid valve 32 is in the off state and the lockup clutch 15 is off, the hydraulic oil in the torque converter 10 becomes relatively hot due to the stirring by the pump impeller 11 and the turbine runner 12. Since the hydraulic oil in the torque converter 10 having a high temperature is supplied to the predetermined portion 52 of the automatic transmission 20, the predetermined portion 52 of the automatic transmission 20 is warmed up.

  At this time, since the orifice 54 is provided in the fourth oil passage L4 connecting the first discharge port 35f and the second discharge port 35g, the hydraulic oil in the torque converter 10 having a high temperature flows to the oil cooler 51. However, most of the hydraulic oil is supplied to a predetermined portion 52 of the automatic transmission 20.

  Further, the predetermined portion 52 of the automatic transmission 20 is a portion where heat loss is large at low temperatures, specifically, the oil pump 53 and the friction engagement member 57. When hydraulic oil in the torque converter 10 having a high temperature is supplied to the oil pump 53, heat loss at a low temperature can be reduced as compared with the case where the hydraulic oil of the entire automatic transmission 20 is warmed.

4) The operation when starting when the oil temperature of the automatic transmission 20 is low will be described.
Also in this case, similarly to 3) described above, warm-up can be promoted, and an effect of improving fuel consumption can be obtained.

5) The operation when the automatic transmission 20 is warmed up and reaches a predetermined temperature will be described.
When the warm-up of the automatic transmission 20 is promoted by the operations of 3) and 4) described above and reaches a predetermined temperature, the torque converter 10 is controlled by performing the control at the normal temperature similar to 1) and 2) described above. An excessive increase in the temperature of the hydraulic oil inside can be suppressed.

  In addition, when electric failure occurs, when power is not supplied to the linear solenoid valve 31 and the solenoid valve 32, the linear solenoid valve 31 and the solenoid valve 32 are turned off. Therefore, similarly to 1) described above, the switching valve 35 is in the first position. The torque converter outlet port 17b is connected to the input port 35c of the switching valve 35 via the first oil passage L1 via the first discharge port 33h and the fourth discharge port 33k. Thus, since the torque converter outlet port 17b is connected to the oil cooler 51, the hydraulic oil in the torque converter 10 is supplied to the oil cooler 51 and cooled. As a result, the automatic transmission 20 can be prevented from being overheated.

  Further, when the switching valve 35 is fixed in the second position, the fourth oil passage L4 that connects the first discharge port 35f and the second discharge port 35g is provided with the orifice 54, so that the temperature is high. A part of the hydraulic oil in the torque converter 10 can flow to the oil cooler 51. Therefore, it is possible to suppress the automatic transmission 20 from being overheated.

  As is apparent from the above description, the hydraulic control device for the automatic transmission according to the first embodiment includes an inlet portion (torque converter inlet port 17a) through which hydraulic fluid flows and an outlet portion (torque converter outlet port) through which hydraulic fluid flows out. 17b), a switching valve 35 connected to the torque converter 10 via the first oil passage L1, and an oil cooler 51 connected to the switching valve 35 via the second oil passage L2. It is equipped with. The switching valve 35 is connected to the input port 35c to which the first oil passage L1 is connected, the first output port 35f to which the second oil passage L2 is connected, and a predetermined part in the automatic transmission 20 other than the oil cooler 51. A second output port 35g connected via a three oil passage L3, and the input port 35c is connected to the first output port 35f and the second output port according to the temperature of the hydraulic oil in the automatic transmission 20. It is configured to be selectively switchable to any one of 35g.

According to this, the hydraulic oil warmed by the torque converter 10 can be selectively supplied to the oil cooler 51 or the predetermined part 52 in the automatic transmission 20 according to the switching of the switching valve 35. That is, at the time of warming up (when the working oil is at a low temperature), the working oil warmed by the torque converter 10 is not supplied to the oil cooler 51 and is not cooled. By being supplied to the portion 52, the entire automatic transmission 20 can be warmed up efficiently and quickly.
Since the hydraulic oil warmed by the torque converter 10 is supplied to the oil cooler 51 and cooled at normal times after the warm-up is completed, overheating of the automatic transmission 20 can be reliably suppressed.

In the present embodiment, the predetermined portion 52 in the automatic transmission 20 is the oil pump 53 or the friction engagement member 57.
According to this, when warming up, the hydraulic oil warmed by the lock-up clutch 15 causes the oil pump 53 and the friction engagement member 57 (clutch C1, C2, brake B1, B2) is preferentially supplied. Therefore, it is possible to warm up the entire automatic transmission 20 more efficiently and quickly.

Further, in the present embodiment, an electromagnetic valve (linear solenoid valve) 31 that generates a control pressure based on the temperature of hydraulic oil in the automatic transmission 20 is further provided, and the switching valve 35 is a control supplied from the linear solenoid valve 31. Based on the pressure, the first output port 35f and the second output port 35g can be selectively switched.
According to this, the switching valve 35 can be appropriately switched and controlled by the control pressure generated by the linear solenoid valve 31.

In the present embodiment, a fourth oil passage L4 that connects both the ports 35f and 35g is provided between the first output port 35f and the second output port 35g, and the fourth oil passage L4 includes an orifice 54, A check valve 55 is provided that restricts the flow from the first output port 35f to the second output port 35g but allows the flow in the direction opposite to the flow.
According to this, when the fixing valve 35 is switched to the second output port 35g and a fixing failure occurs, a part of the hydraulic fluid flowing out from the second output port 35g passes through the fourth oil passage L4 (orifice 54). Therefore, the overheat of the automatic transmission 20 can be suppressed.

-Second embodiment-
Next, a second embodiment of the hydraulic control device for an automatic transmission according to the present invention will be described with reference to FIG.
The switching valve 35 of the first embodiment described above is switched by the linear solenoid valve 31 and the solenoid valve 32. However, the switching valve 35 of the second embodiment is switched only by the solenoid valve 37. The solenoid valve 37 is configured in the same manner as the solenoid valve 32, and outputs a control pressure _PSL to the switching valve 35 according to a current value determined by a duty signal (duty value) transmitted from the control device 40.

The oil chamber 35d of the switching valve 35 receives the control pressure _PSL from the solenoid valve 37 to urge the spool valve element 35a toward the second position. The oil chamber 35e of the switching valve 35 is connected to an oil pan. Further, the control pressure _PSLU from the linear solenoid valve 31 is supplied only to the oil chamber 34e of the lockup control valve 34. In addition, about the structure similar to 1st embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  When the solenoid valve 32 is in the off state and the solenoid valve 37 is also in the off state, the switching valve 35 is in a state where the spool valve element 35a is in the first position, and the torque converter outlet port 17b is connected to the oil cooler 51. . When the solenoid valve 32 is in the off state and the solenoid valve 37 is in the on state, the switching valve 35 is in a state where the spool valve element 35a is in the second position, and the torque converter outlet port 17b is connected to a predetermined part of the automatic transmission 20. 52. Therefore, also in the second embodiment, it is possible to obtain the same operation / effect as the first embodiment described above.

-Third embodiment-
Next, a third embodiment of the hydraulic control device for an automatic transmission according to the present invention will be described with reference to FIG.
The switching valve 35 of the first embodiment described above is switched by the linear solenoid valve 31 and the solenoid valve 32. However, the switching valve 35 of the third embodiment is switched by the linear solenoid valve 38 and the solenoid valve 32. It has become. The linear solenoid valve 38 is, for example, a direct pressure linear solenoid valve, and applies the control pressure P _SLU to the lockup relay valve 33 and the switching valve 35 according to the current value determined by the duty signal (duty value) transmitted from the control device 40. Output. The lock-up control valve 34 has been deleted.

The third bypass port 33n of the lockup relay valve 33 receives the control pressure P _SLU from the linear solenoid valve 38. The oil chamber 35d of the switching valve 35 receives the control pressure _PSLU from the linear solenoid valve 38 to urge the spool valve element 35a toward the second position. In addition, about the structure similar to 1st embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  When the solenoid valve 32 is in the off state and the linear solenoid valve 38 is also in the off state, the switching valve 35 is in a state where the spool valve element 35a is in the first position, and the torque converter outlet port 17b is connected to the oil cooler 51. The When the solenoid valve 32 is in the off state and the linear solenoid valve 38 is in the on state, the switching valve 35 is in a state in which the spool valve element 35a is in the second position, and the torque converter outlet port 17b is set to a predetermined value of the automatic transmission 20. Connected to site 52. Therefore, also in the third embodiment, it is possible to obtain the same operation and effect as the first embodiment described above.

In each of the above-described embodiments, the predetermined portion 52 in the automatic transmission 20 may be configured by both the oil pump 53 and the friction engagement member 57. As shown in FIG. 7, the third oil passage L3 is branched into a first branch oil passage L3a connected to the oil pump 53 and a second branch oil passage L3b connected to the friction engagement member 57. . The switching device 58 is a switching device that is provided at the branch point of the first branch oil passage L3a and the second branch oil passage L3b and can be selectively switched to the first branch oil passage L3a and the second branch oil passage L3b. The switching device 58 is switched by a switching instruction from the control device 40.
Accordingly, the hydraulic oil warmed by the lockup clutch 15 can be selectively and automatically supplied to the oil pump 53 or the friction engagement member 57 in accordance with the switching of the switching device 58.
Further, the switching valve 35 described above may be constituted by a thermal valve. The torque converter 10 may not include the lockup clutch 15.

  DESCRIPTION OF SYMBOLS 10 ... Torque converter, 15 ... Lock-up clutch, 16 ... Lock-up oil chamber, 17 ... Torque converter oil chamber, 20 ... Automatic transmission, 31, 38 ... Linear solenoid valve, 32, 37 ... Solenoid valve, 35 ... Switching valve 35c ... input port, 35f ... first output port, 35g ... second output port, 51 ... oil cooler, 52 ... predetermined part in the automatic transmission, 53 ... oil pump, 57 ... friction engagement member, L1 ... first Oil passage, L2 ... second oil passage, L3 ... third oil passage, L4 ... fourth oil passage.

Claims (5)

A torque converter having an inlet portion through which hydraulic oil flows and an outlet portion through which the hydraulic oil flows out; a switching valve connected to the torque converter via a first oil passage; and the switching valve and the second oil passage. An oil cooler connected via a hydraulic control device for an automatic transmission,
The switching valve is
An input port to which the first oil passage is connected, a first output port to which the second oil passage is connected, and a predetermined part in the automatic transmission other than the oil cooler is connected via a third oil passage. A second output port, and
In the automatic transmission, the input port is configured to be selectively switchable to either the first output port or the second output port according to the temperature of the hydraulic oil in the automatic transmission. Hydraulic control device.   2. The hydraulic control device for an automatic transmission according to claim 1, wherein the predetermined part in the automatic transmission is an oil pump or a friction engagement member. The predetermined part in the automatic transmission is an oil pump and a friction engagement member,
The third oil passage is branched into a first branch oil passage connected to the oil pump and a second branch oil passage connected to the friction engagement member,
The hydraulic control device for an automatic transmission according to claim 1, further comprising a switching device that can be selectively switched between the first branch oil passage and the second branch oil passage. A solenoid valve that generates a control pressure based on the temperature of the hydraulic oil in the automatic transmission;
The switch valve is configured to be selectively switchable to one of the first output port and the second output port based on the control pressure supplied from the solenoid valve. The hydraulic control device for an automatic transmission according to claim 3. Between the first output port and the second output port, a fourth oil passage connecting both ports is provided,
The fourth oil passage is provided with an orifice and / or a check valve that restricts a flow from the first output port to the second output port but allows a flow in a direction opposite to the flow. The hydraulic control device for an automatic transmission according to any one of claims 1 to 4.

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