JP2007046654A - Hydraulic device of automatic transmission for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hydraulic device improved in hydraulic pressure discharging performance from a hydraulic frictional engagement device on a release side without adversely affecting its cost and spatial performances, in an automatic transmission for a vehicle by releasing the hydraulic frictional engagement device. <P>SOLUTION: This hydraulic device 100 is constituted to switch a connection/disconnection switch valve 114 switchable between a connection state for connecting a suction oil passage 112 for sucking hydraulic fluid by a mechanical oil pump 28 and an electric oil pump 140 and an engagement device (clutch C, brake B), and a disconnecting state for disconnecting the connecting state. The switch valve 114 is made in the connecting state (discharge-side position) in disengaging the engagement device, discharging performance of the hydraulic fluid from the release-side engagement device is improved by negative pressure generated in the suction oil passage 112, and the release-side engagement device is quickly released in comparison with a case of discharging the hydraulic fluid to atmospheric pressure. Since only the oil passage from the connection/disconnection switch valve 114 to the suction oil passage 112 is substantially newly needed, which does not adversely affect cost and spatial performances. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a hydraulic device for an automatic transmission for a vehicle in which a shift stage is established by releasing a hydraulic friction engagement device, and more particularly to a technique for discharging hydraulic pressure from a hydraulic friction engagement device to be released. .

  2. Description of the Related Art There is known an automatic transmission of a type that includes a plurality of hydraulic friction engagement devices (hereinafter referred to as engagement devices) such as clutches and brakes, and a predetermined engagement device is released to perform a shift. For example, an automatic transmission is known in which one engagement device is released and the other engagement device is engaged to perform a shift. In such an automatic transmission, in order to suppress the shift shock and improve the shift feeling, the start time and speed of the hydraulic drain (release) of the release side engagement device which is the release side engagement device, The start timing and speed of the hydraulic apply (engagement) of the engagement side engagement device, which is the engagement device on the engagement side, are set in advance, and appropriate speed change is performed.

  In this shifting process, if the hydraulic drain speed of the disengagement side engagement device is slow due to an increase in the viscosity of the hydraulic fluid due to low temperature, the completion of the release is delayed, and the hydraulic fluid cannot be discharged quickly, and the shift time changes, making the shift uncomfortable. There is a risk of causing an increase in the amount of heat absorbed by the frictional engagement element due to dragging, and a decrease in the durability of the frictional engagement element due to an increase in the amount of heat absorbed.

  Therefore, a hydraulic control device for an automatic transmission that includes a quick drain mechanism that quickly discharges the hydraulic pressure of the disengagement side engagement device and that quickly releases the disengagement side engagement device in the shifting process is known. For example, it is described in Patent Document 1. In Patent Document 1, as an oil passage for discharging the hydraulic pressure of the disengagement side engagement device, a small drain oil passage having a small-diameter orifice and a large-diameter orifice are provided, and the large-diameter orifice and the release are provided. A large drain oil passage provided in parallel with a switching valve for connecting / disconnecting to / from the side engagement device, and at the time of shifting in a non-driven state at a predetermined vehicle speed or higher, the switching valve causes the large-diameter orifice and the release-side engagement device to , The hydraulic pressure of the disengagement side engagement device is rapidly discharged through the large drain oil passage in addition to the small drain oil passage.

JP-A-6-341533

  By the way, because the hydraulic fluid becomes very viscous when the temperature becomes extremely low, the oil passage of the hydraulic device itself becomes a pipe resistance, and the hydraulic pressure is discharged through the large drain oil passage in addition to the small drain oil passage. However, the hydraulic pressure of the disengagement side engagement device is not discharged at a desired speed, which may make it difficult to quickly release the disengagement side engagement device.

  For this reason, it is conceivable to supply hydraulic pressure to the back surface of the piston in order to make the return of the piston of the disengagement side engagement device faster. For example, this is the hydraulic circuit 200 shown in FIG.

In FIG. 7, a brake 202 as an engagement device is mainly composed of a piston 204, a friction engagement element 206, a return spring 208, an oil chamber 210, and an oil chamber 212. In the hydraulic circuit 200, a hydraulic pressure P ₂₁₀ supplied (discharged) to the oil chamber 210 via the solenoid valve 214 and the oil passage 216 is controlled by a signal pressure P _S from the solenoid valve 214 (hereinafter referred to as solenoid signal pressure P _S ). a pressure regulating valve 218, a hydraulic _{P 212} for supplying (discharging) is a pressure regulating valve 222 which is controlled by a solenoid signal pressure _{P S} through the oil passage 220 to the oil chamber 212.

Then, when engaging the brake 202 is to increase the solenoid signal pressure _{P S,} to decompress the pressure _{P 212} of the oil chamber 212 by the hydraulic _{P 210} simultaneously regulating valve 222 when boosting the oil chamber 210 by the pressure regulating valve 218 (Refer to solenoid signal pressure P _S -oil chamber 210 oil pressure P ₂₁₀ characteristic map 224, solenoid signal pressure P _S -oil chamber 212 oil pressure P ₂₁₂ characteristic map 226). Further, when to release the brake 202 reduces the solenoid signal pressure _{P S,} the depressurizing the hydraulic pressure _{P 210} in the oil chamber 210 by the pressure regulating valve 218 to boost the pressure _{P 212} in the oil chamber 212 by simultaneously regulating valve 222 ( (See characteristic map 224 and characteristic map 226). Thus, when releasing the brake 202, as shown by the arrow A, the back pressure (that is, the hydraulic pressure P ₂₁₂ ) is supplied to the back surface of the piston 204, so that the piston 204 is moved earlier than the exhaust pressure of the hydraulic pressure P ₂₁₀ alone. It becomes possible to return.

However, since it is necessary to provide the oil chamber 212 on the back surface of the piston 204, the structure of the brake 202 becomes complicated. Further, since the back pressure (that is, the hydraulic pressure P ₂₁₂ ) is required on the back surface of the piston 204, the pressure regulating valve 222 that supplies the pressure to the oil chamber 212 is required. Therefore, the number of parts may increase and the hydraulic circuit may become complicated, which may be disadvantageous in terms of cost and space.

  The present invention has been made against the background of the above circumstances, and the object of the present invention is in terms of cost and space in an automatic transmission for a vehicle in which a gear stage is established by releasing a hydraulic friction engagement device. It is another object of the present invention to provide a hydraulic device for an automatic transmission for a vehicle that improves the discharge performance of hydraulic pressure from a hydraulic friction engagement device on the release side without being disadvantageous.

  That is, the gist of the invention according to claim 1 is that (a) the hydraulic pressure is discharged from a predetermined hydraulic friction engagement device among the plurality of hydraulic friction engagement devices, and the predetermined hydraulic friction engagement device. (B) Suction oil that is connected to an inlet of an oil pump and from which hydraulic oil is sucked by the oil pump A predetermined hydraulic friction engagement device provided between the passage and (c) a communication state in which the suction oil passage and the predetermined hydraulic friction engagement device communicate with each other; And a communication / shutoff switching valve that is brought into a communication state when it is released.

  In this way, in a vehicular automatic transmission in which a gear stage is established by releasing a predetermined hydraulic friction engagement device, hydraulic oil is sucked by the oil pump connected to the suction port of the oil pump. A communication / shutoff switching valve provided so as to be switchable between a communication state for communicating between the suction oil passage to be communicated with a predetermined hydraulic friction engagement device and a shut-off state for blocking is provided to release the predetermined hydraulic friction engagement device. Since the hydraulic fluid of the predetermined hydraulic friction engagement device is discharged to the suction oil passage, for example, due to the negative pressure generated in the suction oil passage, the predetermined hydraulic friction engagement device Therefore, the hydraulic friction engagement device can be quickly released as compared with the fact that the hydraulic oil is discharged to atmospheric pressure. Further, as shown in the background art, a switching valve is necessary even in the case of exhaust pressure to atmospheric pressure, and substantially only an oil passage from the switching valve to the suction oil passage is newly required. So there is no disadvantage in terms of cost and space.

  Here, in the invention according to claim 2, the communication / shutoff switching valve is provided to communicate between the suction oil passage and the predetermined hydraulic friction engagement device at the time of shifting of the vehicle automatic transmission. It further includes an electronic control device that switches from the shut-off state to the communication state. In this case, the negative pressure generated in the suction oil passage improves the discharge performance of the hydraulic fluid from the predetermined hydraulic friction engagement device, and the hydraulic fluid is discharged to the atmospheric pressure as compared with that. The hydraulic friction engagement device can be released quickly.

  In the invention according to claim 3, the electronic control unit is configured to cause the suction oil passage and the predetermined hydraulic friction engagement device to communicate with each other when the oil temperature of the hydraulic oil is lower than the predetermined oil temperature. The communication / shutoff switching valve is switched to a communication state. In this way, even if the hydraulic oil becomes less than the predetermined oil temperature and has a high viscosity, the discharge performance of the hydraulic oil from the predetermined hydraulic friction engagement device is improved by the negative pressure generated in the suction oil passage. Thus, the hydraulic friction engagement device can be quickly released as compared with the hydraulic oil being discharged to the atmospheric pressure.

  According to a fourth aspect of the present invention, the oil pump is operatively connected to an engine and driven by the engine to discharge hydraulic oil, and the oil pump is operated by a rotational drive by an electric motor. An electronic oil pump that discharges oil is connected in parallel, and the electronic control unit increases the rotation speed of the electric motor in accordance with a decrease in the rotation speed of the engine. In this way, even if the amount of hydraulic oil drawn from the suction oil passage by the mechanical oil pump is reduced in accordance with the decrease in the engine speed, the operation from the suction oil passage by the electric oil pump is performed. The suction amount of oil can be increased, and the negative pressure in the suction oil passage can be stably generated. In other words, a desired negative pressure can be generated in the suction oil passage by controlling the rotation speed of the electric motor. Therefore, the hydraulic friction engagement device can be quickly released regardless of the rotational speed of the engine.

  Preferably, the automatic transmission is a planetary gear type multi-stage transmission in which the gear stage is switched by selectively connecting rotating elements of a plurality of sets of planetary gear apparatuses by a hydraulic friction engagement device, etc. It is constituted by various types of automatic transmissions that perform gear shifting by selectively engaging and releasing a plurality of hydraulic friction engagement devices.

  In addition, the mounting posture of the automatic transmission with respect to the vehicle may be a horizontal type such as an FF (front engine / front drive) vehicle in which the transmission axis is in the width direction of the vehicle. It may be a vertical installation type such as an FR (front engine / rear drive) vehicle.

  Further, the planetary gear type multi-stage transmission only needs to be able to achieve a plurality of gear stages alternatively. For example, the planetary gear type multi-stage transmission includes various forward speeds such as 5 forward speeds, 6 forward speeds, 7 forward speeds, and 8 forward speeds. A multi-stage automatic transmission can be used.

  Preferably, as the hydraulic friction engagement device, a multi-plate type, single plate type clutch or brake engaged by a hydraulic actuator, or a belt type brake is widely used. The oil pump that supplies the hydraulic pressure for engaging the hydraulic friction engagement device may be driven by a driving power source such as an engine to discharge the hydraulic oil. Alternatively, it may be driven by a dedicated electric motor provided separately.

  Preferably, the hydraulic control circuit including the hydraulic friction engagement device is responsive to, for example, supplying output hydraulic pressure of a linear solenoid valve directly to a hydraulic actuator (hydraulic cylinder) of the hydraulic friction engagement device. However, it is also possible to control the shift control valve by using the output hydraulic pressure of the linear solenoid valve as a pilot hydraulic pressure, and to supply hydraulic oil from the control valve to the hydraulic actuator.

  Preferably, the plurality of linear solenoid valves are provided, for example, one by one corresponding to each of the plurality of hydraulic friction engagement devices. In the case where there are a plurality of hydraulic friction engagement devices that do not have the same, various modes are possible, such as providing a common linear solenoid valve for them. In addition, it is not always necessary to perform the hydraulic control of all the hydraulic friction engagement devices with the linear solenoid valve. Some or all of the hydraulic control may be pressure control means other than the linear solenoid valve, such as duty control of the ON-OFF solenoid valve. You can go there.

  Preferably, an internal combustion engine such as a gasoline engine or a diesel engine is used as the engine.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a skeleton diagram of a vehicular automatic transmission (hereinafter referred to as an automatic transmission) 10. FIG. 2 is an operation table for explaining operation states of the engagement elements when a plurality of shift speeds are established. The automatic transmission 10 is suitably used for an FF vehicle mounted in the left-right direction (horizontal) of the vehicle, and is a first shift mainly composed of a single pinion type first planetary gear unit 12. Part 14 and a second transmission 20 that is composed of a double pinion type second planetary gear unit 16 and a single pinion type third planetary gear unit 18 and that is mainly composed of Ravigneaux type on a coaxial line, and has an input shaft The rotation of the motor 22 is shifted and output from the output rotating member 24. The input shaft 22 corresponds to an input member. In this embodiment, the input shaft 22 is a turbine shaft of a torque converter 32 that is rotationally driven by an engine 30 that is a power source for traveling. The output rotating member 24 corresponds to an output member of the automatic transmission 10, and an output gear meshing with a differential driven gear (large diameter gear) 36 for transmitting power to the differential gear device 34 shown in FIG. That is, it functions as a differential drive gear. The output of the engine 30 is transmitted to the pair of drive wheels 40 via the torque converter 32, the automatic transmission 10, the differential gear unit 34, and the pair of axles 38. The automatic transmission 10 is substantially symmetrical with respect to the center line, and the lower half of the center line is omitted in FIG.

  The automatic transmission 10 corresponds to a combination of any one of the rotational states (sun gears S1 to S3, carriers CA1 to CA3, ring gears R1 to R3) of the first transmission unit 14 and the second transmission unit 20 according to the combination. Six forward shift stages (forward gear stages) from the first shift stage “1st” to the sixth shift stage “6th” are established, and the reverse shift stage (reverse gear stage) of the reverse shift stage “R” is established. It is done. As shown in FIG. 2, for example, in the forward gear stage, the first speed gear stage is engaged by the engagement of the clutch C1 and the brake B2, and the second speed gear stage is engaged by the engagement of the clutch C1 and the brake B1. The third gear is set by engagement with the brake B3, the fourth gear is set by engagement of the clutch C1 and the clutch C2, and the fifth gear is set by engagement of the clutch C2 and the brake B3. The sixth gear is established by engaging the brake B1. Further, the reverse gear stage is established by the engagement of the brake B2 and the brake B3, and the neutral state is established by releasing any of the clutches C1, C2 and the brakes B1 to B3.

  The operation table of FIG. 2 summarizes the relationship between the above-mentioned shift speeds and the operation states of the clutches C1, C2 and the brakes B1 to B3. Represents the event. Since the one-way clutch F1 is provided in parallel to the brake B2 that establishes the first shift speed “1st”, it is not always necessary to engage the brake B2 at the time of start (acceleration). Further, the gear ratios of the respective gear speeds are the gear ratios of the first planetary gear device 12, the second planetary gear device 16, and the third planetary gear device 18 (= number of teeth of the sun gear / number of teeth of the ring gear) ρ1, ρ2. , Ρ3 as appropriate. In addition, the code | symbol 26 of FIG. 1 is a transmission case.

  The clutches C1 and C2 and the brakes B1 to B3 (hereinafter simply referred to as clutches C and brakes B unless otherwise distinguished) are hydraulic friction engagement devices that are controlled by hydraulic actuators such as multi-plate clutches and brakes. The hydraulic pressure control circuit 100 (see FIG. 3) as a hydraulic device is switched between the engaged and released states by excitation, de-excitation, and current control of the linear solenoid valves SL1 to SL5, and the transient hydraulic pressure at the time of engagement and release Etc. are controlled.

  FIG. 3 is a block diagram illustrating a main part of an electrical control system provided in the vehicle for controlling the automatic transmission 10 of FIG. The electronic control unit 90 includes, for example, a so-called microcomputer having a CPU, a RAM, a ROM, an input / output interface, and the like. The CPU uses a temporary storage function of the RAM and follows a program stored in the ROM in advance. By performing signal processing, output control of the engine 30, shift control of the automatic transmission 10, and the like are executed. For engine control and shift control for controlling the linear solenoid valves SL1 to SL5 as necessary. It is divided into parts.

3, an accelerator operation amount sensor 52 for detecting an operation amount Acc of an accelerator pedal 50, known as a so-called accelerator opening, engine rotational speed sensor 58 for detecting the rotational speed N _E of the engine 30, the engine 30 an intake air quantity sensor 60 for detecting an intake air amount Q, a throttle valve opening sensor for detecting an intake air temperature sensor 62 for detecting the temperature T _a, the opening theta _TH of an electronic throttle valve of the intake air 64, the cooling water temperature sensor 68 for detecting a vehicle speed sensor 66, cooling water temperature T _W of the engine 30 for detecting a vehicle speed V (corresponding to the rotational speed N _OUT of the output rotating member 24), a foot brake pedal is a service brake The lever position (operation position) P of the brake switch 70 and the shift lever 72 for detecting the presence or absence of the operation of 69 The lever position sensor 74 for detecting _SH , the turbine rotation speed sensor 76 for detecting the turbine rotation speed N _T (= the rotation speed N _IN of the input shaft 22), and the temperature of the hydraulic oil in the hydraulic control circuit 100. An AT oil temperature sensor 78 and the like for detecting the AT oil temperature T _OIL are provided. From these sensors and switches, the engine speed N _E , the intake air amount Q, the intake air temperature T _A , the throttle valve open Signals indicating degrees θ _TH , vehicle speed V, output shaft rotational speed N _OUT , engine coolant temperature T _W , presence / absence of brake operation, lever position P _SH of shift lever 72, turbine rotational speed N _T , AT oil temperature T _OIL, etc. It is supplied to the electronic control unit 90.

FIG. 4 is a main part circuit diagram showing a part of the hydraulic control circuit 100 that controls engagement and release of the clutches C1 and C2 and the brakes B1 to B3. The hydraulic control circuit 100 includes engagement hydraulic pressure supply / discharge valve devices 102, 104, 106, 108, 110 and a suction oil passage 112, and hydraulic actuators (hydraulic cylinders) for the clutches C1, C2 and brakes B1 to B3. The engagement hydraulic pressures P _C1 , P _C2 , P _B1 , P _B2 , P _B3 are supplied to A _C1 , A _C2 , A _B1 , A _B2 , A _B3 , and the hydraulic actuators A _C1 , A _C2 , A _B1 , A _The engagement hydraulic pressures P _C1 , P _C2 , P _B1 , P _B2 , and P _B3 are discharged from _B2 and A _B3 .

The engagement hydraulic pressure supply / discharge valve device 102 adjusts and outputs the line hydraulic pressure PL to an engagement pressure corresponding to a command signal from the electronic control device 90, a suction oil passage 112, and a hydraulic actuator A _C1. And a solenoid valve 116 that outputs a signal pressure P ₁₁₆ for switching the communication / shutoff switching valve 114. Similarly, the engagement hydraulic pressure supply / discharge valve devices 104, 106, 108, 110 also include linear solenoid valves SL2 to SL5, communication / cutoff switching valves 118, 120, ₁₂₂ , ₁₂₄ , signal pressure P ₁₂₆ , And solenoid valves ₁₂₆ , ₁₂₈ , ₁₃₀ , and ₁₃₂ that output P128, P130, and P132. Since the linear solenoid valves SL1 to SL5, the communication / shutoff switching valves 114, 118, 120, 122, 124 and the solenoid valves 116, 126, 128, 130, 132 are basically the same, respectively, Description of the other engagement hydraulic pressure supply / discharge valve devices 104, 106, 108, 110 will be omitted.

The line hydraulic pressure PL supplied to the linear solenoid valve SL1 is adjusted to a magnitude corresponding to, for example, the throttle valve opening θ _TH by a relief type pressure regulating valve 134 that is well known with the hydraulic pressure discharged from the oil pump as a source pressure. Pressed.

  As shown in FIG. 1, the oil pump is disposed between the torque converter 32 and the automatic transmission 10, and is rotated by the engine 30 together with the pump impeller of the torque converter 32 connected to the engine 30. This is a mechanical oil pump 28 that discharges hydraulic oil. Further, an electric oil pump 140 that includes an electric motor 136 and an oil pump 138 connected to the electric motor 136 and that discharges hydraulic oil by rotating the oil pump 138 by the electric motor 136 is used as an oil pump. It is connected in parallel with the type oil pump 28.

  The hydraulic oil discharged from the discharge port 142 of the pressure regulating valve 134 when the line hydraulic pressure PL is regulated by the pressure regulating valve 134 is connected to the suction port 144 of the mechanical oil pump 28 and the suction port 146 of the electric oil pump 140. The suction is performed by the mechanical oil pump 28 and the electric oil pump 140 through the suction oil passage 112. In other words, the suction oil passage 112 is an oil passage that is connected to the suction ports 144 and 146 and through which the hydraulic oil is sucked by the mechanical oil pump 28 and the electric oil pump 140. Thereby, a negative pressure is generated in the suction oil passage 112.

In the engagement hydraulic pressure supply / discharge valve device 102, the communication / shutoff switching valve 114 is provided on one shaft end side of a spool valve element B ₁₁₄ (not shown) provided in the communication / shutoff switching valve 114. spring imparting B ₁₁₄ and the linear solenoid valve SL1 and the thrust _{F 148} extending from the linear solenoid valve SL1 is brought through the clutch C1 are communicated to supply the engagement pressure _{P C1} is supplied to the hydraulic actuator _{a C1} (solid line) side position and 148, the engagement oil pressure of the spool valve element _{B 114} is provided on the other axial end side of the spool valve element _{B 114} from the suction oil passage 112 and the clutch C1 are communicated hydraulic actuator _{a C1} is allowed to communicate to the suction oil passage 112 Oil chamber 15 that receives the signal pressure P ₁₁₆ to urge it toward the discharge (broken line) side position where PC ₁ is discharged. 0.

In the communication / shutoff switching valve 114 configured as described above, the solenoid valve 116 does not output the signal pressure P _{116, and the} spool valve element B ₁₁₄ is urged to the supply side position by the thrust F ₁₄₈ of the spring 148, so that the linear solenoid When the engagement hydraulic pressure _PC1 is output from the linear solenoid valve SL1 when the valve SL1 and the clutch C1 are communicated, the engagement hydraulic pressure _PC1 is input to the input port 152, and the hydraulic actuator from the clutch side port 154 Supplied to A _C1 and the clutch C1 is engaged. Further, when there is no hydraulic pressure output from the linear solenoid valve SL1, the engagement pressure P _C1 that has been supplied to the hydraulic actuator A _C1 is inputted from the hydraulic actuator A _C1 to the clutch-side port 154, the linear solenoid valve via the input port 152 It is discharged from the atmospheric pressure port EX of SL1 to the atmospheric pressure, and the clutch C1 is released.

Further, in the communication / shutoff switching valve 114, when the solenoid valve 116 outputs the signal pressure P ₁₁₆ and the spool valve element B ₁₁₄ is urged to the discharge side position, the suction oil passage 112 and the clutch C1 are communicated. the engagement pressure _{P C1} that has been supplied to the hydraulic actuator _{a C1} is inputted from the hydraulic actuator _{a C1} to the clutch-side port 154, it is discharged from the discharge port 156 to the suction oil passage 112. Thus, when brought through the suction oil passage 112 and the clutch C1 are communicated by communicating / blocking switching valve 114 upon release of the clutch C1, since hydraulic oil of the hydraulic actuator A _C1 is discharged to the suction oil passage 112 to produce negative pressure, The discharge performance of the hydraulic oil from the hydraulic actuator A _C1 is improved, and the clutch C1 is quickly released as compared with the discharge of the hydraulic oil to the atmospheric pressure.

As described above, the communication / cutoff switching valve 114 is provided so as to be switchable between a communication state (discharging side position) for communicating between the suction oil passage 112 and the hydraulic actuator _AC1 and a blocking state (supply side position) for blocking. at the same time is, is switchably provided a cut-off state in which the space between the linear solenoid valve SL1 and the hydraulic actuator a _C1 communication state to (discharge side position) and communicates (supply-side position). For example, when the clutch C1 is released, the communication / shutoff switching valve 114 is in a communication state in which the suction oil path 112 and the hydraulic actuator _AC1 are in communication with each other, that is, switched to the discharge side position.

FIG. 5 is a functional block diagram illustrating a main part of the control function of the electronic control device 90. In FIG. 5, the shift control means 160 makes a shift determination based on the actual vehicle speed V and the accelerator operation amount Acc from, for example, a previously stored shift diagram (shift map) shown in FIG. 6, and executes the determined shift. A shift output is performed to control one of the linear solenoid valves SL1 to SL5, and any two of the clutches C1, C2 and the brakes B1, B2, B3 are engaged. For example, when the shift output is to achieve the sixth gear, the drive for outputting the engagement hydraulic pressures P _C2 and P _B1 to the linear solenoid valves SL2 and SL3 in order to engage the clutch C2 and the brake B1. Output a signal.

  The communication / shut-off switching valve control means 162 controls one of the solenoid valves 116, 126, 128, 130, 132 when the automatic transmission 10 is shifted by the shift control means 160, and is connected to the linear solenoid valve and the engagement side. The communication / shutoff switching valves 114, 118, 120, 122, 124 connected to the engagement side engagement device are switched from the discharge side position to the supply side position in order to communicate with the hydraulic actuator of the combined device, In order to communicate between the suction oil passage 112 and the hydraulic actuator of the disengagement side engagement device, the communication / cutoff switching valves 114, 118, 120, 122, 124 connected to the disengagement side engagement device are connected from the supply side position. Switch to the discharge side position.

For example, the shift output by the shift control means 160 is a signal output to the linear solenoid valve SL3 and a linear solenoid valve for releasing the brake B3 and engaging the brake B1 at the fifth gear to perform a 5 → 6 upshift. when a signal stops to SL5 are communicated / shut-off changeover valve control means 162 switches the communication / cutoff switching valve 120 without outputting a command to output the signal pressure P ₁₂₈ to the solenoid valve 128 to the supply side with communicating the linear solenoid valve SL3 and the hydraulic actuator a _B1 by, by to switch the communication / cutoff switching valve 124 to the discharge side and outputs an instruction to output the signal pressure P ₁₃₂ to the solenoid valve 132 Suction oil passage 112 and hydraulic actuator _AB3 are communicated. As a result, the discharge of hydraulic fluid from the hydraulic actuator A _B3 is improved by the negative pressure generated in the suction oil passage 112, and the brake B3 is released quickly compared to the discharge of hydraulic fluid to atmospheric pressure. Can be.

By the way, the lower the AT oil temperature T _OIL is, the higher the viscosity of the hydraulic oil becomes, and the lowering of the hydraulic oil discharge performance decreases. Therefore, the communication / shutoff switching valve control means 162 is engaged with the suction oil passage 112 and the disengagement side engagement when the automatic transmission 10 is shifted by the shift control means 160 when the AT oil temperature T _OIL is _lower than the predetermined oil temperature T _OIL ′. The communication / shutoff switching valves 114, 118, 120, 122, 124 connected to the disengagement side engagement device may be switched to the discharge side position in order to communicate with the hydraulic actuator of the device. In other words, the communication / cutoff switching valve control means 162 communicates / cuts off switching valves 114, 118 when the automatic transmission 10 is shifted by the shift control means 160 when the AT oil temperature T _OIL is _{equal to} or higher than the predetermined oil temperature T _OIL ′. , 120, 122, and 124 may cause the linear solenoid valve and the hydraulic actuator of the disengagement side engagement device to communicate with each other to discharge the hydraulic oil from the atmospheric pressure port EX of the linear solenoid valve to the atmospheric pressure. That is, even if the hydraulic oil becomes lower than the predetermined oil temperature T _OIL ′, the discharge performance of the hydraulic oil from the disengagement side engagement device is improved, and the hydraulic oil is released in the same manner as when the hydraulic oil is higher than the predetermined oil temperature T _OIL ′ In order to release the side engagement device, the communication / shut-off switching valve control means 162 is connected to the suction oil passage 112 at the time of shifting of the automatic transmission 10 when the AT oil temperature T _OIL is _lower than the predetermined oil temperature T _OIL ′. The hydraulic actuator of the release side engagement device is communicated with the hydraulic actuator.

The electric oil pump control means 164 operates the electric motor 136 and causes the oil pump 138 to discharge the hydraulic oil. Specifically, since the intake amount of working oil from the suction oil passage 112 by the more mechanical oil pump 28 engine rotational speed N _E is lowered it is lowered, the electric oil pump control means 164, the engine rotational speed N The rotational speed of the electric motor 136 is increased by a predetermined amount in accordance with the decrease in _E , and the amount of hydraulic oil drawn from the suction oil passage 112 by the electric oil pump 140 is increased. In other words, the electric oil pump control means 164, by controlling the rotational speed of the electric motor 136 in accordance with the engine rotational speed N _E, to generate the desired negative pressure at the suction oil passage 112.

For example, the electric oil pump control means 164, a negative pressure is caused to occur in a stable manner in the suction oil passage 112, to the engine rotational speed N _E release-side engagement device regardless are brought promptly released, the engine rotational It is increased rotational speed of the amount corresponding to the electric oil pump 140 corresponding to the intake amount of working oil from the suction oil passage 112 by the mechanical oil pump 28 that is reduced according to the decrease of the speed N _E and the electric oil pump the relationship between the rotational speed of the engine rotational speed N _E and an electric motor 136 which is predetermined as the intake amount of working oil from the suction oil passage 112 is increased by 140, the electric based on the actual engine speed motor The rotational speed of 136 is controlled.

  As described above, according to this embodiment, the suction oil passage 112 through which the hydraulic oil is sucked by the mechanical oil pump 28 and the electric oil pump 140 and the engagement device (clutch C, brake B) communicate with each other. The communication / shutoff switching valves 114, 118, 120, 122, 124 provided to be switchable between a communication state to be shut off and a shut-off state to be shut off are provided between the suction oil passage 112 and the disengagement side engagement device when the engagement device is released. Since the communication state (discharge side position) for communication is set, the release side engagement is caused by, for example, the negative pressure generated in the suction oil passage 112 when the hydraulic oil of the release side engagement device is discharged to the suction oil passage 112. The discharge performance of the hydraulic fluid from the device is improved, and the disengagement side engagement device is released quickly compared to the hydraulic fluid being discharged to atmospheric pressure. Further, as shown in the background art, a switching valve is necessary even in the case of exhaust pressure to atmospheric pressure, and substantially the communication / cutoff switching valves 114, 118, 120, 122, 124 to the suction oil passage 112 are required. Since only the oil passage is newly required, there is no disadvantage in terms of cost and space.

  Further, according to the present embodiment, when the automatic transmission 10 is shifted, the communication / cutoff switching valve 114 is used to connect the suction oil passage 112 and the disengagement side engagement device by the communication / cutoff switching valve control means 162. , 118, 120, 122, and 124 are switched to the discharge side, the negative pressure generated in the suction oil passage 112 improves the discharge performance of the hydraulic oil from the disengagement side engagement device, and the hydraulic oil is discharged to atmospheric pressure. Compared to being done, the disengagement side engagement device is quickly released.

For example, when the AT oil temperature _{T OIL} is lower than the predetermined oil temperature _{T OIL} ', since the suction oil passage 112 and the release-side engagement device is communicated by communication / cutoff switching valve control unit 162, AT oil temperature _{T OIL} Even if the oil temperature becomes lower than the predetermined oil temperature T _OIL ′ and becomes high viscosity, the negative pressure generated in the suction oil passage 112 improves the discharge performance of the hydraulic oil from the disengagement side engagement device, and the hydraulic oil is at atmospheric pressure. The disengagement side engagement device is quickly released as compared with the case of being discharged.

Further, according to this embodiment, since the rotational speed of the electric motor 136 by the electric oil pump control means 164 according to the decrease of the engine rotational speed N _E is increased, mechanical with a decrease of the engine rotational speed N _E Even if the suction amount of the hydraulic oil from the suction oil passage 112 by the oil pump 28 is reduced, the suction amount of the hydraulic oil from the suction oil passage 112 by the electric oil pump 140 is increased, and the suction oil passage 112 Negative pressure is generated stably. In other words, a desired negative pressure is generated in the suction oil passage 112 by controlling the rotational speed of the electric motor by the electric oil pump control means 164. Thus, the engine rotational speed N release-side engagement device regardless _E are brought promptly released.

  As mentioned above, although the Example of this invention was described in detail based on drawing, this invention is applied also in another aspect.

  For example, in the above-described embodiment, the present invention can be applied even if the electric oil pump 140 is not necessarily provided as the oil pump. On the contrary, the present invention can be applied even if only the electric oil pump 140 is used as the oil pump.

Further, in the above-described embodiment, the position of the spool valve element B ₁₁₄ is moved by the solenoid valve in the communication / cutoff switching valve 114 by the thrust F _{148 of the} spring 148 and the signal pressure P ₁₁₆ by the solenoid valve 116. A direct acting type in which the valve element B ₁₁₄ is directly moved may be used. The other communication / shutoff switching valves 118, 120, 122, and 124 may also be direct acting.

Further, various communication / shutoff switching valves 114, 118, 120, 122, and 124 may be suitably used in addition to the embodiments. For example, communication / shutoff switch valve 114 has an input port 152 and the clutch-side port 154 is in a state communicating with the exhaust port 156 and the clutch-side port 154 to switch the state of communication, one spool B ₁₁₄ Although it was performed by movement, each switching may be performed by providing a spool valve element for each switching.

  In the above-described embodiment, the automatic transmission 10 is configured such that a shift is executed by releasing and engaging the hydraulic friction engagement device. However, the gear position is changed by releasing the hydraulic friction engagement device. The present invention can be applied even to an automatic transmission that is established and shifts.

  The above description is only an embodiment, and the present invention can be implemented in variously modified and improved forms based on the knowledge of those skilled in the art.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a skeleton diagram illustrating a configuration of a vehicle automatic transmission to which the present invention is applied. It is a figure explaining the operating state of the engagement element of the automatic transmission for vehicles of FIG. It is a block diagram explaining the principal part of the control system with which the automatic transmission for vehicles of FIG. 1 is provided. FIG. 4 is a circuit diagram of a main part showing a portion for controlling engagement and disengagement of clutches C1 and C2 and brakes B1 to B3 in the hydraulic control circuit of FIG. 3. It is a functional block diagram explaining the principal part of the control function of the electronic control apparatus of FIG. It is a figure which shows an example of the shift map used with the automatic transmission control means of FIG. This is a conventional hydraulic circuit that supplies hydraulic pressure to the back surface of the piston in order to speed up the return of the piston of the disengagement side engagement device.

Explanation of symbols

10: Automatic transmission 28 for vehicle: Mechanical oil pump 30: Engine 90: Electronic control device 100: Hydraulic control circuit (hydraulic device)
112: Suction oil passages 114, 118, 120, 122, 124: Communication / cutoff switching valve 140: Electric oil pump 144, 146: Suction port C1, C2: Clutch (hydraulic friction engagement device)
B1, B2, B3: Brake (hydraulic friction engagement device)

Claims (4)

Automatic vehicular shift in which a shift stage is established by discharging hydraulic pressure from a predetermined hydraulic friction engagement device among a plurality of hydraulic friction engagement devices and releasing the predetermined hydraulic friction engagement device Machine hydraulic system,
A suction oil passage that is connected to the suction port of the oil pump and from which hydraulic oil is sucked by the oil pump;
Switching between a communication state for communicating between the suction oil passage and the predetermined hydraulic friction engagement device and a shut-off state for blocking are provided, and the communication state is established when the predetermined hydraulic friction engagement device is released. A hydraulic device for an automatic transmission for vehicles, comprising: a communication / shutoff switching valve.   An electronic control device for switching the communication / shut-off switching valve from a shut-off state to a communication state in order to make the suction oil passage communicate with the predetermined hydraulic friction engagement device during a shift of the vehicle automatic transmission; The hydraulic device for a vehicle automatic transmission according to claim 1, further comprising:   When the oil temperature of the hydraulic oil is lower than a predetermined oil temperature, the electronic control unit sets the communication / shutoff switching valve in a communication state to connect the suction oil passage and the predetermined hydraulic friction engagement device. The hydraulic device for an automatic transmission for a vehicle according to claim 2 to be switched. The oil pump is operatively connected to an engine and driven by the engine to discharge hydraulic oil, and an electric oil pump that discharges hydraulic oil by rotational driving by an electric motor; Are connected in parallel,
The hydraulic apparatus for an automatic transmission for a vehicle according to claim 2 or 3, wherein the electronic control unit increases the rotation speed of the electric motor in accordance with a decrease in the rotation speed of the engine.

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