JP2010175029A - Lubricating oil pressure control device for automatic transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lubricating oil pressure control device for automatic transmission, capable of preventing suction of air or increase in load of an oil pump when the temperature of lubricating oil is low. <P>SOLUTION: The device is configured so that the pressure of lubricating oil in a secondary regulator valve 9 can be varied at least by oil temperature, and includes a pressure control spring (return quantity adjustment means) 30 which increases, when the temperature of excess oil is a predetermined temperature or lower, the return quantity of the excess oil to a suction oil passage 4. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a lubricating oil pressure adjusting device for an automatic transmission mounted on a vehicle such as an automobile.

  In this type of automatic transmission lubricating oil pressure adjusting device, the lubricating oil of the oil pan is sucked by the oil pump through the strainer, and the lubricating oil pressurized by the oil pump is adjusted to the line pressure by the primary regulator valve. The lubricating oil supplied to the throttle control valve and adjusted to the line pressure is adjusted to the lubricating oil pressure by the secondary regulator valve and supplied to the torque converter and the clutch, and surplus oil resulting from the pressure adjustment is supplied to the oil pump suction oil passage (For example, refer to Patent Document 1).

JP-A-2-275168

  By the way, in the conventional lubricating oil pressure adjusting device, since the viscosity increases as the temperature of the lubricating oil decreases, the passage resistance flowing through the oil passage increases, the lubricating oil accumulates in the clutch, and the lubricating oil is supplied to the oil pan. Return amount may be insufficient. As a result, the strainer may inhale air, and hydraulic pulsation may occur or the pump pressure may decrease. In addition, when the temperature of the lubricating oil is low, there is a problem that the suction resistance of the strainer increases and the load on the oil pump increases accordingly.

  The present invention has been made in view of the above-described conventional situation, and provides a lubricating oil pressure regulating device for an automatic transmission that can prevent air suction at a low temperature of the lubricating oil and an increase in the load of the oil pump. It is an issue.

  The present invention provides an oil pan for storing lubricating oil, an oil pump for sucking the lubricating oil in the oil pan through a suction oil passage connected to a strainer, and adjusting the lubricating oil discharged from the oil pump to a line pressure. A primary regulator valve that pressurizes and supplies the pressure to the line pressure oil passage, and adjusts the lubricating oil from the primary regulator valve to a lubricating pressure and supplies it to the lubricating oil passage, and returns excess oil resulting from the pressure adjustment to the suction oil passage. A lubricating oil pressure adjusting device for an automatic transmission comprising a secondary regulator valve, wherein the pressure adjustment of the lubricating oil of the secondary regulator valve is variable at least according to the oil temperature, and when the oil temperature is equal to or lower than a predetermined temperature, A return amount adjusting means for increasing the return amount of the surplus oil to the suction oil passage is provided.

  According to the lubricating oil pressure adjusting device of the present invention, when the oil temperature is equal to or lower than the predetermined temperature, the return amount of the excess oil to the suction oil passage is increased, so that the lubricating oil is accumulated in the clutch. Even if the return amount to the oil pan is insufficient, the increased amount of lubricating oil returns to the oil passage of the oil pump, preventing strainer air suction and reducing the load on the oil pump due to the suction resistance of the strainer. it can. In this case, the amount of lubricating oil supplied to the torque converter and the clutch decreases, but the cooling performance is not affected because the temperature of the lubricating oil is low. Further, since excessive supply of low temperature lubricating oil to the clutch can be suppressed, the drag torque of the clutch can be reduced.

It is a schematic block diagram for demonstrating the lubricating oil pressure regulation apparatus of the automatic transmission by Example 1 of this invention. It is a figure of the pressure regulation spring which functions as a return amount adjustment means of the said lubricating oil pressure regulator. It is a characteristic view of the pressure regulating spring. It is a figure which shows the modification of the return amount adjustment means of the said Example 1. FIG. It is a schematic block diagram for demonstrating the lubricating oil pressure regulation apparatus of the automatic transmission by Example 2 of this invention.

  1 to 3 are diagrams for explaining a lubricating oil pressure adjusting device for an automatic transmission according to a first embodiment of the present invention. FIG. 1 is a schematic configuration diagram of the lubricating oil pressure adjusting device, and FIG. 2 is a return amount. FIG. 3 is a characteristic diagram of the pressure regulating spring, and FIG. 3 is a characteristic diagram of the pressure regulating spring that functions as the adjusting means.

  In the figure, reference numeral 1 denotes a lubricating oil pressure adjusting device for an automatic transmission mounted on an automobile. The lubricating oil pressure adjusting device 1 includes an oil pan 2 that stores lubricating oil, an oil pump 5 that sucks the lubricating oil in the oil pan 2 through a suction oil passage 4 connected to a strainer 3, and the oil pump 5 Is supplied through the pump oil passage 16, and the primary regulator valve 7 that regulates the lubricating oil to the line pressure A and supplies it to the line pressure oil passage 6, And a secondary regulator valve 9 that adjusts the lubricating oil to the lubricating pressure B and supplies the lubricating oil to the lubricating pressure oil passage 8.

  The primary regulator valve 7 returns the lubricant adjusted to the line pressure A to the suction oil passage 4 through the primary return oil passage 10 as surplus oil by the pressure adjustment.

  The secondary regulator valve 9 supplies the lubricating oil adjusted to the lubricating pressure B to the clutch 12 from the lubricating pressure oil path 8 through the clutch oil path 11 and from the lubricating oil path 8 to the torque converter oil path 13. The excess oil resulting from the pressure adjustment is returned to the suction oil passage 4 via the secondary return oil passage 15.

  An orifice 11 a is provided on the downstream side of the clutch 12 in the clutch oil passage 11, and the lubricating oil supplied to the clutch 12 is returned to the oil pan 2 through a return oil passage 20.

  The lubricating oil supplied to the torque converter 14 is supplied to the oil cooler 21 through the orifice 13a, where it is cooled and returned to the oil pan 2 through the return oil passage 22. An orifice 22 a is provided on the downstream side of the return oil passage 22.

  The primary regulator valve 7 has two spool valves 24 and 25 arranged in the valve body 7a so as to be movable in the axial direction, and one spool valve 25 is connected to a pump oil passage 16 and a line pressure oil passage by a pressure regulating spring 26. 6 has a structure biased so as to communicate with each other.

  The line pressure oil passage 6 is connected to the oil passage 6a through an orifice 6c. An oil passage 27 communicating with an oil chamber 7b formed by the valve body 7a and the spool valve 25 is connected.

  When the line pressure A acts on the oil chamber 7b through the oil passage 27 and the pump discharge pressure C from the oil pump 5 increases, the spool valve 25 moves against the biasing force of the pressure adjusting spring 26. The primary return oil passage 10 is opened, and excess oil is returned to the suction oil passage 4.

  The secondary regulator valve 9 has a structure in which a spool valve 29 is disposed in the valve body 9a so as to be movable in the axial direction, and the spruce valve 29 is urged by a pressure adjusting spring 30 to close the secondary return oil passage 15. . The lubricating pressure oil passage 8 is connected to an oil passage 28 communicating with an oil chamber 9 b formed by a valve body 9 and a spool valve 29.

  When the line pressure A from the line pressure oil passage 6 and the lubricating oil pressure B increase, the spool valve 29 moves against the pressure regulating spring 30 by the oil pressure acting on the oil chamber 9b through the oil passage 28, and the secondary return oil. Open road 15. Thereby, the lubricating oil B is held at a predetermined pressure.

  The pressure regulating spring 30 of the secondary regulator valve 9 makes it possible to vary the pressure of the lubricating oil according to the atmospheric temperature of the pressure regulating spring 30, and consequently the oil temperature, and when the temperature is low, the lubricating oil suction oil passage 4 It functions as a return amount adjusting means for increasing the return amount to. Specifically, the pressure regulating spring 30 is made of a shape memory alloy having a characteristic that its urging force rapidly decreases when the temperature is around 0 degrees.

  FIG. 3 is a characteristic diagram showing the relationship between the load required for starting drain in the secondary regulator valve 9 and the spring temperature, and consequently the oil temperature, using the pressure regulating spring 30 of the present embodiment. In the secondary regulator valve 9 of this embodiment, the load necessary for starting the oil drain is reduced between 15 ° C. and −20 ° C., thereby adjusting the drain flow rate. In this case, the regulator pressure is about ½, and a larger amount of lubricating oil is returned to the suction oil passage 4 at low temperatures than at normal temperature.

  As described above, the pressure adjusting spring 30 has a smaller spring biasing force at a low temperature than at a normal temperature and contracts with a small force (see FIGS. 2A and 2B).

  According to the present embodiment, when the ambient temperature of the secondary regulator valve 9 and thus the temperature of the lubricating oil regulated thereby is, for example, 0 ° C. or less, the return amount of surplus oil to the suction oil passage 4 increases. Even if the amount of return to the oil pan 2 is insufficient due to the accumulation of the lubricating oil in the clutch 12, the amount of return oil to the suction oil passage 4 of the oil pump 5 is increased and air suction of the strainer 3 can be prevented. In addition, the load on the oil pump 5 due to the suction resistance of the strainer 3 can be reduced. In this case, the amount of lubricating oil supplied to the torque converter 14 and the clutch 12 is reduced, but the cooling performance is not affected because the temperature of the lubricating oil is low.

  Further, since the amount of lubricating oil supplied to the clutch 12 is reduced, the drag torque of the clutch can be reduced.

  In this embodiment, since the return amount adjusting means is configured by the pressure regulating spring 30 made of a shape memory alloy, an increase in the return oil amount is realized with a simple structure in which only some parts of the existing secondary regulator valve 9 are changed. And increase in cost and size of the apparatus can be suppressed.

  4A and 4B are diagrams showing a modification of the return amount adjusting means of the first embodiment. In this modification, a pressure adjusting plate 36 made of a shape memory alloy is disposed between a pressure adjusting spring 35 made of a normal spring material and the valve body 9a.

  The pressure adjusting plate 36 is formed in a circular arc shape at normal temperature and urges the spool valve 29 via the pressure adjusting spring 35 so as to be deformed into a flat plate shape when the lubricating oil temperature becomes, for example, 0 ° C. or less. As a result, the length of the compression spring 35 of the pressure regulating spring 35, and hence the urging force, becomes small, the spool valve 29 moves backward, and the secondary return oil passage 15 is opened. Also in this modified example, the same effect as the above-described embodiment can be obtained.

  FIG. 5 is a schematic configuration diagram for explaining a lubricating oil pressure regulator according to Embodiment 2 of the present invention. In the figure, the same reference numerals as those in FIG. 1 denote the same or corresponding parts.

  The return amount adjusting means of this embodiment includes a hydraulic supply oil passage 40 connected to an oil chamber 9c in which a pressure regulating spring 39 'of the secondary regulator valve 9 is disposed, and a solenoid valve that opens and closes the hydraulic supply oil passage 40. 41 and an ECU 42 that controls opening and closing of the solenoid valve 41. The pressure regulating spring 39 ′ is made of a normal spring material and has a biasing force smaller than that of the pressure regulating spring 39 in the first embodiment. The hydraulic supply oil passage 40 is connected to the pump oil passage 16 of the oil pump 5.

  The ECU 42 receives the lubricating oil temperature from the temperature sensor and the shift position from the shift position sensor.

  When the lubricating oil temperature is normal temperature, the ECU 42 opens the hydraulic pressure supply passage 40 by the solenoid valve 41 and supplies hydraulic pressure to the oil chamber 9c. As a result, the pressure regulating spring 39 'and the spruce valve 29 by the hydraulic pressure open and close the secondary return oil passage 15 with a normal urging force, and adjust the pressure of the lubricating oil to a predetermined value.

  On the other hand, when the lubricating oil temperature is lower than a predetermined value, for example, 0 ° C. or lower, the ECU 42 closes the hydraulic pressure supply passage 40 by the solenoid valve 41. As a result, the hydraulic pressure in the oil chamber 9 c of the secondary regulator valve 9 is released, and the spool valve 29 opens the secondary return oil passage 15. As a result, the amount of oil returned to the oil pump 5 side is increased.

  The ECU 42 closes the hydraulic pressure supply passage 40 by the solenoid valve 41 during non-shifting to release the hydraulic pressure on the pressure regulating spring 39 side, and opens the hydraulic pressure supply oil passage 40 during shifting. This suppresses excessive supply of lubricating oil to the clutch 12 during non-shifting, and increases the amount of lubricating oil supplied to the clutch 12 during shifting.

  According to this embodiment, when the lubricating oil temperature is low, the hydraulic pressure supply passage 40 is closed and the secondary return oil passage 15 is opened, so that the amount of lubricating oil to the suction oil passage 4 is increased and the air in the strainer 3 is increased. Suction can be prevented and the load on the oil pump 5 due to the suction resistance of the strainer 3 can be reduced, and the same effect as in the above embodiment can be obtained.

  In this embodiment, the amount of lubricating oil applied to the clutch 12 is reduced during non-shifting, so that the drag torque of the clutch can be reduced.

  Further, since the amount of lubricating oil to the clutch 12 and the torque converter 14 is increased at the time of shifting, the power transmission efficiency can be increased.

  In the above embodiment, the present invention has been described with respect to the stepped variable automatic transmission. However, the present invention is naturally applicable to a continuously variable automatic transmission.

DESCRIPTION OF SYMBOLS 1 Lubricating oil pressure regulator 2 Oil pan 3 Strainer 4 Suction oil path 5 Oil pump 6 Line pressure oil path 7 Primary regulator valve 8 Lubrication pressure oil path 9 Secondary regulator valve 30 Pressure regulating spring (return amount adjusting means)
36 Pressure adjusting plate (return amount adjusting means)
40 Hydraulic supply oil passage (return amount adjustment means)
41 Solenoid valve (return amount adjusting means)
42 ECU (return amount adjusting means)
A Line pressure B Lubrication pressure

Claims (1)

An oil pan for storing lubricating oil, an oil pump for sucking the lubricating oil in the oil pan through a suction oil passage connected to a strainer, and adjusting the lubricating oil discharged from the oil pump to a line pressure. A primary regulator valve to be supplied to the oil passage; a secondary regulator valve for adjusting the lubricating oil from the primary regulator valve to a lubricating pressure and supplying the lubricating oil to the lubricating oil passage; and returning surplus oil by the pressure adjustment to the suction oil passage; A lubricating oil pressure adjusting device for an automatic transmission comprising:
Provided is a return amount adjusting means for adjusting the pressure of the lubricating oil of the secondary regulator valve at least according to the oil temperature, and increasing the return amount of the surplus oil to the suction oil passage when the oil temperature is equal to or lower than a predetermined temperature. A lubricating oil pressure adjusting device for an automatic transmission.

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