JP3662968B2 - Lubricating oil passage configuration of transmission - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a lubricating oil passage configuration for supplying lubricating oil to a lubricating portion of a transmission.
[0002]
[Prior art]
The transmission has parts that require much lubrication, such as shafts and gears, and it is necessary to forcibly feed lubricating oil to these lubrication parts. For example, in a transmission having a hydraulically operated clutch for setting a gear position, the oil discharged from a hydraulic pump driven by the engine and adjusted to a predetermined shift control hydraulic pressure by a pressure regulating valve (regulator valve) While being supplied to a hydraulically operated clutch or the like, oil supplied from the hydraulic pump to the pressure regulating valve is supplied to the lubricating portion through a discharge port (hereinafter referred to as a lubrication port) provided in the pressure regulating valve. (See Japanese Patent Publication No. 4-745570).
[0003]
In some transmissions having such a lubricating oil path configuration, a pressure adjusting valve is provided with a discharge port (hereinafter referred to as a drain port) separate from the lubricating port, and a part of the oil supplied from the hydraulic pump. In some cases, the lubricating oil pressure does not become too high by causing the oil oil to flow out to the oil sump through the drain oil passage, or by connecting the drain oil passage to the suction port of the hydraulic pump to perform so-called recirculation.
[0004]
[Problems to be solved by the invention]
However, in the low engine speed range, the discharge flow rate from the pump decreases, and accordingly, the amount of oil that can be used for lubrication also decreases. For this reason, when oil is discharged from the drain port when the discharge flow rate from the pump is small, there is a problem that insufficient lubrication occurs in the lubricating portion that receives the supply of oil from the lubrication port. In particular, oil that has been recirculated from the drain port will discharge a larger amount of oil than the oil that is simply connected to the oil sump due to the suction negative pressure of the pump. There is a high possibility of causing insufficient lubrication.
[0005]
The present invention has been made in view of such a problem, and enables a sufficient amount of lubricating oil to be secured even in a low rotation range where the discharge flow rate from the hydraulic pump is small, and further includes a torque converter with a lock-up clutch. It is an object of the present invention to provide a lubricating oil path configuration of a transmission that can achieve both the engagement operation of a lockup clutch in a low rotation range and sufficient lubrication of a lubricating portion.
[0006]
[Means and Actions for Solving the Problems]
In order to achieve the above object, the present invention adjusts the oil discharged from the hydraulic pump to a predetermined shift control hydraulic pressure and discharges the oil supplied from the hydraulic pump through the two discharge ports. (For example, the regulator valve 4 in the embodiment ), and a lubricating oil passage that is connected to one of the two discharge ports ( for example, the lubricating port 4d in the embodiment ) and supplies lubricating oil to the lubricating portion of the transmission, A drain oil passage connected to the other of the two discharge ports ( for example, the drain port 4e in the embodiment ), and the discharge port and the drain oil are opened when the discharge pressure of the other of the discharge ports exceeds the relief pressure. A first on-off valve that communicates with the road (for example, the relief valve 6 in the embodiment), and a torque that is branched from the lubricating oil path and has a lock-up clutch. Lock-up control oil passage for supplying oil to control the operation of the lock-up clutch to the converter, and the hydraulic pressure in the torque converter (torque converter internal pressure) is released when the cracking pressure is exceeded, and the oil in the torque converter is discharged And a second open / close valve (for example, torque converter check valve 9 in the embodiment). In the present invention, the relief pressure at which the first on-off valve opens is set lower than the transmission control hydraulic pressure (line pressure) and higher than the cracking pressure at which the second on-off valve opens. .
[0007]
When such a first opening / closing valve is provided, when the amount of oil discharged from the pump is small and the oil discharge pressure from the drain port is lower than a predetermined pressure (relief pressure), the first opening / closing valve in the closed state is provided . The drain port and the drain oil passage are shut off by the valve. For this reason, since almost all of the oil supplied from the hydraulic pump to the pressure regulating valve is supplied to the lubricating oil passage through the lubrication port, the lubrication part is sufficiently lubricated. On the other hand, when the amount of oil discharged from the pump is sufficient and the oil discharge pressure from the drain port becomes higher than a predetermined pressure, the first on- off valve opens and the drain port, drain oil passage, Is communicated. For this reason, a part of the oil supplied from the hydraulic pump is discharged to the drain oil passage, and the lubricating oil pressure is prevented from becoming too high. Similarly, when such a second on-off valve is provided, when the discharge amount from the pump is small and the oil discharge pressure from the drain port is lower than a predetermined pressure (cracking pressure), the first valve is in the closed state. Because a sufficient amount of oil is discharged from the lubrication port by the open / close valve, a part of the oil supplied to the lubrication oil passage flows into the lockup control oil passage, and the torque converter internal pressure is engaged with the lockup clutch. The hydraulic pressure required can be increased. On the other hand, when the torque converter internal pressure becomes higher than the predetermined pressure, the second on-off valve is opened to prevent oil from being discharged and the torque converter internal pressure from becoming too high.
[0008]
Further, the relief pressure for opening the first opening / closing valve is set lower than the shift control hydraulic pressure (line pressure) and set higher than the cracking pressure for opening the second opening / closing valve. Opening and closing of the open / close valve does not affect the line pressure and the torque converter internal pressure.
[0009]
The drain oil passage may be connected to the suction port of the hydraulic pump. According to this, when the discharge flow rate from the pump becomes excessive, a large amount of oil can be efficiently discharged by recirculation. On the other hand, when the discharge flow rate from the pump is small, recirculation can be blocked by the first open / close valve in the closed state, and the shortage of lubricating oil can be reliably prevented.
[0010]
【Example】
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a hydraulic circuit for a torque converter of a transmission that employs a lubricating oil passage configuration according to the present invention. The torque converter (torque converter) 1 includes an impeller 1a, a turbine 1b, and a stator 1c, and further includes a lock-up clutch 2 that can directly connect the impeller 1a and the turbine 1b. A release oil passage 2a is formed on the back side of the lock-up clutch 2, and the operation control of the lock-up clutch 2 is performed by the hydraulic pressure supply / discharge control to the release oil passage 2a.
[0011]
This hydraulic circuit has a hydraulic pump 3. The hydraulic pump 3 is driven by an engine (not shown) and discharges oil at a flow rate corresponding to the rotational speed to the oil passage 101. The oil passage 101 is connected to a not-illustrated gear setting hydraulic clutch and brake. An oil passage 103 is branched from the oil passage 101, and the oil passage 103 is connected to the left end port of the regulator valve (pressure regulating valve) 4.
[0012]
In the regulator valve 4, the hydraulic pressure received at the left end port pushes the spool 4a to the right, and the hydraulic pressure supplied to the left intermediate port from the switching valve (not shown) through the oil passage 104 (but only during reverse travel) is the spool 4a. The oil in the oil passage 101 is adjusted to the line pressure (transmission control hydraulic pressure) by the balance between the force that pushes the right and the spring 4b pushes the spool 4a to the left.
[0013]
A supply port 4c to which an oil passage 103a branched from the oil passage 103 is connected is formed in the middle portion of the regulator valve 4 in the left-right direction. The lubrication port 4d and the drain port are adjacent to the right and left of the supply port 4c. 4e is formed. An oil passage (lubricating oil passage) 105 is connected to the lubrication port 4d, and the oil passage 105 is connected to the lubricating portion L1 at the front of the transmission. An oil passage 105 a branches from the middle of the oil passage 105, and this branch oil passage (lock-up control oil passage) 105 a is connected to the lock-up shift valve 5.
[0014]
A lockup shift valve (hereinafter referred to as a shift valve) 5 has a spool 5a urged to the right by a spring 5b, and hydraulic pressure (when the lockup clutch 2 is turned on) to a right end port via an oil passage 106. (For example, the hydraulic pressure sent from the solenoid valve SE shown in FIG. 4), the spool 5a moves to the left against the urging force of the spring 5b as shown in the figure, and the oil passage 105a is moved to the first position of the torque converter 1. While connecting to the oil passage 109 connected to the 1 internal pressure port 1d, the oil passage 107 connected to the release oil passage 2a is opened to the drain. When the right end port is not subjected to hydraulic pressure, the spool 5a is moved to the right by the urging force of the spring 5b, connecting the oil passage 105a to the oil passage 107 and connecting the oil passage 109 to the oil passage 110. The oil passage 110 is connected to the lubricating portion L2 at the rear portion of the transmission through the oil cooler 8.
[0015]
On the other hand, the drain port 4 e of the regulator valve 4 is connected to the left end port of the relief valve (open / close valve) 6 through the oil passage 111. The leaf valve 6 has a spool 6a biased to the left by a spring 6b, and the spool 6a is moved to the right against the biasing force of the spring 6b by the hydraulic pressure supplied to the left end port (hereinafter referred to as “this”). The oil passage 111 is connected to the oil passage (drain oil passage) 113 by opening operation). The hydraulic pressure (relief pressure) in the left end port required for opening the relief valve 6 is lower than the line pressure and higher than the operating pressure of the torque converter check valve 9 described later. The oil passage 113 is connected to the suction port of the hydraulic pump 3, and an oil passage 113 a branched from the oil passage 113 is opened in the oil sump 7. The lubrication port 4d and the drain port 4e may be connected by an oil passage.
[0016]
An oil passage 115 is connected to the second internal pressure oil passage 1 e communicating with the inside of the torque converter 1, and the oil passage 115 is connected to the torque converter check valve 9. An oil passage 115 a branched from the oil passage 115 is connected to the right end port of the valve 9. The torque converter check valve 9 has a spool 9a biased to the right by a spring 9b, and the spool 9a is moved to the left against the biasing force of the spring 9b by the hydraulic pressure supplied to the right end port. (When the hydraulic pressure in the right end port reaches the operating pressure), the oil passage 115 is connected to the oil passage 117. The oil passage 117 is connected to the oil passage 110 described above.
[0017]
In the hydraulic circuit configured as described above, of the oil supplied to the oil passage 103, oil other than the oil supplied to the left end port of the regulator valve 4 flows into the supply port 4c of the regulator valve 4 through the oil passage 103a. To do. The spool 4a of the regulator valve 4 is moved to the right due to the aforementioned balance of force. For this reason, the supply port 4c communicates with the lubrication port 4d and the drain port 4e. Oil flows from the supply port 4c to the lubrication port 4d.
[0018]
Here, when the lock-up clutch 2 is off, part of the oil that flows from the supply port 4c to the lubrication port 4d flows through the oil passage 105 to the front lubrication portion L1, and the remaining oil flows through the oil passage 105a and the spool 5a. Flows to the oil passage 107 and further to the release oil passage 2a through the shift valve 5 in the right-handed state. In addition, since the throttles 11 and 12 are respectively provided on the downstream side of the oil passage 105a in the oil passage 105 and the oil passage 105a, the oil flowing through the oil passages 105 and 105a by setting these opening areas. The amount can be set as appropriate. Thus, the lubricating oil can be supplied to the front lubricating portion L1, and the hydraulic pressure (clutch back pressure) necessary to turn off the lockup clutch 2 can be generated in the release oil passage 2a. The oil leaked from the release oil passage 2a into the torque converter 1 flows into the oil passage 110 through the first internal pressure oil passage 1d and the oil passage 109, and further through the shift valve 5, and then flows into the rear lubricating portion L2 through the oil cooler 8. . Thus, the lubricating oil can be supplied also to the lubricating portion L2.
[0019]
On the other hand, when the lock-up clutch 2 is on, part of the oil that flows from the supply port 4c to the lubrication port 4d flows through the oil passage 105 to the front lubrication portion L1, and the remaining oil flows through the oil passage 105a and the spool 5a. The oil flows into the oil passage 109 through the shift valve 5 in the left-moved state and flows into the torque converter 1. For this reason, the torque converter internal pressure rises. On the other hand, the oil in the release oil passage 2a is drained through the shift valve 5, and the hydraulic pressure in the release oil passage 2a is lowered, so that the lockup clutch 2 is engaged. Further, when the torque converter internal pressure exceeds the operating pressure of the torque converter check valve 9, part of the oil in the torque converter 1 flows to the rear lubricating portion L <b> 2 through the second internal pressure oil passage 1 e, the oil passages 115 and 117, and the oil cooler 8. .
[0020]
Here, when the engine and pump 3 have high rotation speeds and the discharge flow rate from the pump 3 is sufficient, the amount of oil supplied to the supply port 4c increases, but the oil passage 111 and the relief valve 6 are increased. When the hydraulic pressure generated at the left end port of the valve exceeds the relief pressure, the relief valve 6 is opened, and the oil passage 111 communicates with the oil passage 113. Of the oil thus supplied to the supply port 4c, the oil that does not flow into the oil passages 105 and 105a is directly returned to the suction port of the pump 3 through the oil passages 111 and 113, and the oil pressure of the oil supplied to the front lubricating portion L1. And the torque converter internal pressure is prevented from becoming too high. Since the relief pressure is set lower than the line pressure as described above, the opening of the relief valve 5 does not cause fluctuations in the line pressure. Further, since the relief pressure is set higher than the cracking pressure of the torque converter check valve 9, it does not hinder the increase of the torque converter internal pressure necessary for engaging and operating the lockup clutch 2.
[0021]
On the other hand, when the rotational speed of the engine and the pump 3 is low and the discharge flow rate from the pump 3 is small, the amount of oil supplied to the supply port 4c is also small. In this case, since the hydraulic pressure generated at the oil path 111 and the left end port of the relief valve 5 does not reach the relief pressure, the relief valve 6 is kept closed and the oil path 111 and the oil path 113 are shut off. . For this reason, all of the oil supplied to the supply port 4c flows into the oil passages 105, 105a, and a sufficient amount of lubricating oil to be supplied to the front lubricating portion L1 can be secured, and the torque converter internal pressure is applied to the lockup clutch 2. The oil pressure can be raised to the required oil pressure. Therefore, even when the discharge flow rate from the pump 3 is small, the lockup clutch 2 can be engaged and operated by applying hydraulic pressure to the right end port of the shift valve 5.
[0022]
Here, FIGS. 2 to 5 show the entire shift control hydraulic circuit employing the lubricating oil passage configuration according to the present invention. These four figures show each part of the shift control hydraulic circuit, and these four figures constitute one shift control hydraulic circuit. Also, among the oil passages in each figure, those with a circled alphabet (A to Z, a to f) at the end means that they are connected to oil passages with the same alphabet in other figures. To do. Furthermore, a cross in the figure means that the portion is drained.
[0023]
This shift control hydraulic circuit controls the supply of hydraulic pressure to the three clutches CL1 to CL3 and the two brakes B1 and B2 for setting the shift speed, thereby controlling the shift of a transmission (not shown). The shift control hydraulic circuit is supplied with hydraulic oil from the hydraulic pump 10, and the hydraulic oil is adjusted to the line pressure by the regulator valve 20 and used as control hydraulic pressure for the clutch and the like.
[0024]
In this hydraulic circuit, in addition to the regulator valve 20, a manual valve 25 connected to a shift lever in the driver's seat and operated by a driver's manual operation, six solenoid valves SA to SF, and ten hydraulic pressures. Actuating valve (Reducing valve 30, LH shift valve 35, FWD pressure switching valve 40, REV pressure switching valve 45, delivery valve 50, pressure relief valve 55, lockup shift valve 60, lockup control valve 65, torque converter check A valve 70 and a relief valve 75) which is an on-off valve constituting the present invention, and a torque converter 90 are provided. Solenoid valves SA, SC, and SF are normally open valves, and these valves are opened when the solenoid is off. On the other hand, the solenoid valves SB, SD, and SE are normally closed valves, and these valves are closed when the solenoid is off.
[0025]
The parts shown in FIGS. 3 to 5 are mainly a hydraulic circuit for setting the gear position, but a detailed description thereof will be omitted here. On the other hand, the portion shown in FIG. 2 is a hydraulic circuit for controlling the operation of the lockup clutch 92 and for lubricating the lubricating portions L11 and L12 in the torque converter 90, similarly to the circuit shown in FIG. The shift valve 60, the torque converter check valve 70 and the relief valve 75 have the same functions as the shift valve 5, the torque converter check valve 9 and the relief valve 6 of FIG. The control valve 65 controls the engagement force of the lockup clutch 92 by controlling the torque converter internal pressure and the back pressure of the lockup clutch 92.
[0026]
FIG. 6 shows the relationship between the rotational speed N of the engine (hydraulic pump 10), the line pressure PL, the lubricating oil pressure PLU, the lubricating oil flow rate QLU, and the torque converter internal pressure PLC in the thus configured hydraulic circuit. On the other hand, FIG. 7 shows the relationship between the engine speed N and the hydraulic pressure or the like when the relief valve 75 is not provided. When the relief valve 75 is not provided, the lubricating oil pressure PLU, the lubricating oil flow rate QLU, and the torque converter internal pressure PLC gradually increase from the low engine speed range to the medium engine speed range of the engine rotation N. The hydraulic pressure is required to engage the lockup clutch 92 in the high rotation range. On the other hand, when the relief valve 75 is present, the lubricating oil pressure PLU, the lubricating oil flow rate QLU, and the torque converter internal pressure PLC rise suddenly in the low rotation range and become sufficient. It can be seen from the comparison between the two figures that the line pressure PL is not affected by the presence of the relief valve 75.
[0027]
【The invention's effect】
As described above, in the lubricating oil passage configuration of the present invention, when the amount of oil discharged from the pump is small and the oil discharge pressure from the drain port is lower than a predetermined pressure, the first on- off valve in the closed state The drain port and the drain oil passage are shut off by the (relief valve 6) . For this reason, since almost all of the oil supplied to the pressure regulating valve (regulator valve 4) is supplied to the lubricating oil passage through the lubricating port, the lubricating portion can be sufficiently lubricated. On the other hand, when the discharge amount from the pump is sufficient and the oil discharge pressure from the drain port becomes higher than a predetermined pressure (relief pressure) , the first on-off valve is opened to operate the drain port and the drain port. The oil passage is communicated. For this reason, a part of the oil supplied to the pressure regulating valve is discharged to the drain oil passage, and the lubricating oil pressure is prevented from becoming too high. Note that the relief pressure first on-off valve is opened and closed, because they are lower than the shift control hydraulic pressure (line pressure), is not the opening and closing of the first on-off valve leading to variations in the transmission control oil pressure .
[0028]
Further, since the lock-up control oil passage for supplying oil for controlling the operation of the lock-up clutch is branched from the lubricating oil passage, lubrication is performed even when the discharge flow rate from the pump is small due to the action of the first on- off valve. Since a sufficient amount of oil is discharged from the port, a part of the oil supplied to the lubricating oil passage is caused to flow through the lockup control oil passage so that the torque converter internal pressure becomes the oil pressure required for the engagement operation of the lockup clutch. Can be raised. At this time, when the torque converter internal pressure becomes higher than a predetermined pressure (cracking pressure), the second opening / closing valve (torque check valve 9) is opened, so that the torque converter internal pressure is prevented from becoming too high. Since the relief pressure at which the first on-off valve opens and closes is set higher than the cracking pressure at which the second on-off valve opens and closes, the opening and closing of the first on-off valve engages the lock-up clutch. Therefore, the increase in the torque converter internal pressure is not hindered.
[0029]
If the drain oil passage is connected to the suction port of the hydraulic pump, a large amount of oil can be efficiently discharged by recirculation when the discharge flow rate from the pump becomes excessive. On the other hand, when the discharge flow rate from the pump is small, recirculation can be prevented by the open / close valve in the closed state, and a shortage of lubricating oil can be reliably prevented.
[Brief description of the drawings]
FIG. 1 is a circuit diagram of a hydraulic circuit for a torque converter that employs a lubricating oil passage configuration according to the present invention.
FIG. 2 is a part of an overall circuit diagram of a shift control hydraulic circuit that employs the lubricating oil passage configuration.
FIG. 3 is a part of an overall circuit diagram of a shift control hydraulic circuit adopting the lubricating oil path configuration.
FIG. 4 is a part of an overall circuit diagram of a shift control hydraulic circuit adopting the lubricating oil path configuration.
FIG. 5 is a part of an overall circuit diagram of a shift control hydraulic circuit that employs the lubricating oil passage configuration;
FIG. 6 is a graph showing the relationship between the engine speed and the line pressure, lubricating oil pressure, torque converter internal pressure and lubricating oil amount in the case of the present invention.
FIG. 7 is a graph showing a relationship between a conventional engine speed and line pressure, lubricating oil pressure, torque converter internal pressure, and lubricating oil amount.
[Explanation of symbols]
1,90 Torque converter 2,92 Lock-up clutch 4,20 Regulator valve 6,75 Relief valve 5,60 Lock-up shift valve 9,70 Torcon check valve

Claims (2)

A pressure regulating valve for regulating the oil discharged from the hydraulic pump to a predetermined shift control hydraulic pressure, and discharging the oil supplied from the hydraulic pump through two discharge ports;
A lubricating oil passage connected to one of the two discharge ports and supplying lubricating oil to a lubricating portion of the transmission;
A drain oil passage connected to the other of the two discharge ports ;
A first on-off valve that is opened when the other discharge pressure of the discharge ports exceeds the relief pressure and communicates the discharge port and the drain oil passage;
A lockup control oil passage that branches from the lubricating oil passage and supplies oil for controlling the operation of the lockup clutch to a torque converter having a lockup clutch;
A second on-off valve that is opened when the hydraulic pressure in the torque converter exceeds a cracking pressure and discharges the oil in the torque converter;
4. A lubricating oil passage configuration of a transmission , wherein the relief pressure is set lower than the shift control hydraulic pressure and higher than the cracking pressure . The lubricating oil path configuration of the transformer according to claim 1, wherein the drain oil path is connected to a suction oil path of the hydraulic pump.

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