WO2007074633A1

WO2007074633A1 - Hydraulic device for multistage transmission

Info

Publication number: WO2007074633A1
Application number: PCT/JP2006/324713
Authority: WO
Inventors: Satoshi Tanaka
Original assignee: Komatsu Ltd.
Priority date: 2005-12-27
Filing date: 2006-12-12
Publication date: 2007-07-05
Also published as: JP2007177868A

Abstract

A hydraulic device for a multistage transmission prevents an excessive amount of oil from being supplied to the transmission. A first pump (21) is constantly connected to the multistage transmission (1) via a first hydraulic-oil line (P1), and a second pump (22) is connected to either the first hydraulic-oil line (P1) or a second hydraulic-oil line (P2) via connection- destination switchover means (122). Hydraulic-oil pressure control means (110) outputs a control signal to pressure regulation means (111) according to a speed stage selected by shift control means (100), thereby the hydraulic-oil pressure control means (110) regulating the pressure of the first hydraulic-oil line (P1). In a high-rotation-speed high-temperature operation region, hydraulic-oil flow rate control means (120) causes, via the connection-destination switchover means (122), the second pump (22) to be connected to the second hydraulic-oil line (P2) to prevent an excessive amount of oil from being supplied to the multistage transmission (1). Lubricant flow rate control means (130) controls, according to a selected speed stage, the flow rate of lubricant supplied from a torque converter (2) to a lubricant circuit of the multistage transmission (1).

Description

Specification

Hydraulic equipment for multi-stage transmission

Technical field

TECHNICAL FIELD [0001] The present invention relates to a hydraulic apparatus for supplying hydraulic oil to a multi-stage transmission, and more particularly to a hydraulic apparatus for supplying hydraulic oil to a multi-stage transmission in which different clutch holding pressures are set for each speed stage. About.

Background art

[0002] For example, a vehicle such as a dump truck may be equipped with an automatic transmission for automatically switching a gear position (speed stage). Here, in Patent Document 1 (see, for example, paragraphs 0022 to 0023, FIGS. 1 and 2), a plurality of clutches (friction engagement devices) are selectively coupled and released to operate the planetary gear mechanism to change speed. And a hydraulic control device that supplies and discharges hydraulic oil to and from each clutch and regulates the hydraulic oil.

Patent Document 1: Japanese Patent Laid-Open No. 2001-74130

Disclosure of the invention

Problems to be solved by the invention

[0003] In the technique described in the above-mentioned document, the hydraulic pressure (clutch holding pressure) required to hold the clutch in the engaged state is different for each clutch. In other words, the clutch corresponding to the gear used at the low speed stage is applied with a larger torque in a coupled state, so that a higher clutch holding pressure is required.

[0004] Conventionally, the pressure of hydraulic oil discharged from an oil pump is first set to a value slightly higher than the maximum value in the holding oil pressure required by all clutches by the main relief knob. Adjusted to Thereafter, the hydraulic pressure supplied to each clutch is adjusted to an appropriate local pressure corresponding to the holding hydraulic pressure of each clutch by a proportional control valve corresponding to each clutch.

[0005] However, when only a clutch for which a relatively low local hydraulic pressure is sufficient is engaged (that is, when a relatively high speed stage is selected), the main pressure of the hydraulic oil is Necessary The pressure is higher than necessary. The main pressure is also low, and the loss for dropping the hydraulic pressure to the local pressure is large.

[0006] Also, as an oil pump, a gear pump is often used due to cost limitations, but the amount of oil discharged from the gear pump varies depending on the number of revolutions of the engine that drives the gear pump. For this reason, a pump of sufficient size that can secure the amount of discharged oil required for idling rotation is adopted.

[0007] However, when the engine speed is higher, more oil than necessary is discharged from the oil pump. Excess hydraulic oil generated at the time of high engine speed is also discharged as excess oil from the main relief valve, and is supplied to a low-pressure load circuit such as a hydraulic circuit of a torque converter or a lubricating oil circuit of a speed changer. Therefore, the loss of the pressure loss at the main relief valve is large at high engine speeds.

[0008] In addition, as described above, a part of the low-pressure hydraulic oil that has also been discharged from the main relief lubrication force is supplied to the lubricating oil circuit of the transmission. Depending on the speed stage currently selected for the transmission, the number of gears to be operated differs, and the amount of lubricating oil required varies depending on the number of operating gears. In general, the smaller the number of operating gears, the smaller the required amount of lubricating oil. Conventionally, the amount of lubricating oil has been set based on the maximum required amount of oil in all speed stages. For this reason, there is a relatively small amount of lubricating oil! / When only a small amount of lubricating oil is required! / When a speed stage is selected!

[0009] The present invention has been made in view of the above-described problems, and an object thereof is to provide a hydraulic device for a multi-stage transmission that can reduce loss due to wasteful supply of pressure oil. Means for solving the problem

A hydraulic device for a multi-stage transmission according to the present invention is a hydraulic device for a multi-stage transmission that supplies hydraulic oil to the multi-stage transmission, and the multi-stage transmission has different clutch holding pressures at a plurality of speed stages. The pressure adjusting means that adjusts the pressure of hydraulic oil supplied from the pump to the multi-stage transmission according to the given control signal, and the speed stage selected from each speed stage, Hydraulic pressure control means for supplying hydraulic oil to the multi-stage transmission at a pressure corresponding to the clutch holding pressure of the selected speed stage by giving a control signal to the pressure adjusting means. In the embodiment of the present invention, the pump is configured to include a first pump connected to the multi-stage transmission and a second pump connected to the multi-stage transmission via the connection destination switching means. Further, in the embodiment of the present invention, the hydraulic oil flow control means for controlling the flow rate of the hydraulic oil supplied to the multi-stage transmission is further provided, and the hydraulic oil flow control means is an operation detected by the operating state detection means. Based on the state, it is determined whether or not the vehicle is in a predetermined operation region set in advance. If it is determined that the vehicle is in the predetermined operation region, the connection between the second pump and the multi-stage transmission is released, If it is determined that the vehicle is in an operation region other than the operation region, the second pump is connected to the multi-stage transmission via the connection destination switching means.

[0012] In the embodiment of the present invention, it further comprises a lubricating oil flow rate control means for controlling the supply of lubricating oil to the multi-stage transmission, and the lubricating oil flow rate control means is in accordance with the selected speed stage. Controls the amount of lubricating oil supplied to the multi-stage transmission.

In the embodiment of the present invention, a gear pump is used as the pump.

[0014] In an embodiment of the present invention, a hydraulic device for a multi-stage transmission that supplies hydraulic oil to a multi-stage transmission that includes a torque converter, the multi-stage transmission includes clutch holdings that are respectively different for a plurality of speed stages. Pressure is set, connected to the multi-stage transmission via the first hydraulic oil line, connected to the multi-stage transmission via the first pump that discharges hydraulic oil and the first hydraulic oil line, Alternatively, the second pump is connected to the torque converter via the second hydraulic oil line and discharges the hydraulic oil, and the second pump is connected to the first hydraulic oil line or the second hydraulic oil based on the input control signal. Connecting point switching means to be connected to one of the lines, pressure adjusting means for adjusting the pressure of the first hydraulic oil line, and the speed for low pressure control in which the selected speed stage is preset. If it is a stage, control the pressure adjustment means. By giving a signal, the pressure in the first hydraulic fluid line is reduced, and if the selected speed stage is a preset speed stage for high pressure control, a control signal is given to the pressure adjusting means. Thus, the hydraulic fluid pressure control means for increasing the pressure of the first hydraulic oil line tl, the operational state detecting means for detecting the operational state, and the operational state detected by the operational state detecting means are the predetermined high rotation and high temperature. In this case, the second pump is connected to the second hydraulic fluid line via the connection switching means, and the detected operating state indicates an operating region other than the predetermined high rotation and high temperature region. In the case, the second pump is activated first via the connection switching means Hydraulic oil flow control means connected to the oil line, torque converter force The lubricating oil line for supplying the discharged hydraulic oil to the lubricating oil circuit of the multi-stage transmission as lubricating oil, and the flow rate for adjusting the flow of the lubricating oil line When the adjusting means and the selected speed stage are preset speed stages, a lubricating oil flow rate control that reduces the amount of lubricating oil flowing through the lubricating oil line by giving a control signal to the flow rate adjusting means. Means.

Brief Description of Drawings

FIG. 1 is an explanatory diagram showing a functional configuration of a hydraulic device for a multi-stage transmission.

FIG. 2 is a hydraulic circuit diagram of a hydraulic device for a multi-stage transmission.

FIG. 3 is an explanatory diagram showing a relationship between a speed stage and a transmission gear.

FIG. 4 is a flowchart showing main pressure control.

FIG. 5 is a flowchart showing main flow control.

FIG. 6 is a flowchart showing lubricant flow control.

Explanation of symbols

[0016] 1 ... multi-stage transmission, 2 ... torque converter, 3 ... engine, 4 ... retarder, 5 ... oil cooler, 10 ... hydraulic device for multi-stage transmission, 20 ... pump part, 21 ... 1st pump, 22 ... 2nd pump, 23 ... Drive shaft, 30 ... Hydraulic oil circuit, 31 ... Flow rate switching valve, 32 ... Main relief valve, 33 ... IJ relief valve, 34 ... Solenoid valve, 35 ... Neuro pressure relief valve, 36 ... Solenoid valve, 37 ... Pilot pressure relief valve, 38 ... Check valve, 40 ... Lubricating oil circuit, 41 ... Lubrication Oil relief valve, 42 ... Flow path diameter switching valve, 43 ... Lubricating oil circuit, 44 ... Solenoid valve, 45 ... Flow rate switching valve, 50 ... Transmission control unit, 51 ... Transmission Control valve group, 52 ... Transmission controller, 53, 54 ... Oil temperature sensor, 55 ... Engine speed sensor, 100 ... Shift control means, 110 ... Hydraulic pressure control 111 ... Pressure adjusting means, 120 ... Hydraulic oil flow control means, 121 ... Operating state detection means, 122 ... Connection destination switching means, 130 ... Lubricating oil flow control means, 131 ... Flow adjustment means, Ρ1 ... · 1st hydraulic oil line, Ρ2 ··· 2nd hydraulic oil line, Ρ3 ··· Lubricant oil line, P21 ... Main discharge oil line, Ρ22 ··· Sub discharge oil line, P31 ... Main hydraulic oil line, P 32 ... Sub hydraulic oil line

BEST MODE FOR CARRYING OUT THE INVENTION

[0017] FIG. 1 shows a hydraulic device for a multi-stage transmission (hereinafter sometimes abbreviated as "hydraulic device"). It is composition explanatory drawing which shows an active composition typically. The hydraulic device 10 supplies hydraulic oil and lubricating oil to a multi-stage transmission 1 of a vehicle (may be abbreviated as “TM” in the figure) 1 and torque converter 2 (in the case of abbreviated as “TC” in the figure). Supply hydraulic fluid to

[0018] The multi-stage transmission 1 is configured to change gears by operating a planetary gear mechanism by selectively coupling and releasing a plurality of clutches. Since the specific configuration is known, further description is omitted.

However, in the present embodiment, the planetary gear mechanism of the multi-stage transmission 1 has seven transmission gears, that is, “high”, “low”, “first”, “second”, “second” for forward movement. It shall have six gears “3” and “fourth” and one gear for reverse. A combination of the seven clutches for selecting these seven transmission gears and one clutch for locking the torque converter, a total of eight clutches are incorporated in the multi-stage transmission 1. And A module in which each clutch itself and a hydraulic actuator (for example, a hydraulic piston) for coupling and releasing each clutch are combined is called a “clutch pack”. Accordingly, eight clutch packs are incorporated in the multi-stage transmission 1 of the present embodiment.

The hydraulic device 10 includes, for example, a first pump 21 and a second pump 22, a shift control means 100, a hydraulic oil pressure control means 110, a pressure adjustment means 111, a hydraulic oil flow control means 120, The operation state detecting means 121, the connection destination switching means 122, the lubricating oil flow rate control means 130, and the flow rate adjusting means 131 can be provided. Specific examples of these parts will be described later, but their functions will be briefly described first. First, the shift control means 100 controls the coupling and release of gears based on, for example, a user instruction or a driving state of the vehicle.

Next, the present embodiment includes a plurality of pumps 21 and 22 each configured as a gear pump, for example. That is, conventionally, a force that has ensured a necessary hydraulic oil flow rate with a single large pump. In this embodiment, the required flow rate is obtained by dividing the pump into a plurality of pumps 21 and 22.

The first pump 21 is always connected to the multistage transmission 1 via the first hydraulic oil line P1, and supplies the hydraulic oil to the multistage transmission 1. The pressure in the first hydraulic oil line P1 is adjusted by, for example, pressure adjusting means 111 configured as a relief valve. From pressure adjusting means 111 The surplus oil is supplied to the torque converter 2 via the second hydraulic oil line P2.

[0023] The second pump 22 is connected to either the first hydraulic oil line P1 or the second hydraulic oil line P2 via, for example, a connection destination switching means 122 configured as a flow rate switching valve. When the second pump 22 is connected to the first hydraulic oil line P1, the hydraulic oil from the first pump 21 and the second pump 22 flows into the first hydraulic oil line P1, respectively. Supplied to gearbox 1. That is, in this case, the first pump 21 is assisted by the second pump 22. On the other hand, when the second pump 22 is connected to the second hydraulic oil line P2, only the hydraulic oil discharged from the first pump 21 flows into the first hydraulic oil line P1, and the second hydraulic oil line The hydraulic oil discharged from the second pump 22 and the surplus oil from the pressure adjusting means 111 flow into P2. Since the torque converter 2 includes a hydraulic circuit that operates at a lower pressure than the multi-stage transmission 1, the load on the second pump 22 is reduced.

The hydraulic oil pressure control means 110 outputs a control signal to the pressure adjustment means 111 in accordance with the speed stage selected by the shift control means 100, whereby the pressure of the first hydraulic oil line P1 (hereinafter referred to as main (Also referred to as pressure) is adjusted to a value according to the selected speed stage (details will be described later as main pressure control). For example, the hydraulic oil pressure control means 110 may increase the main pressure when the selected speed stage is low, and decrease the main pressure when the selected speed stage is high. A control signal is output to the pressure adjusting means 111. Thus, when a higher speed stage is selected, a main pressure corresponding to the holding oil pressure of the selected clutch can be obtained, and loss can be reduced.

Next, the hydraulic fluid flow control means 120 outputs a control signal to the connection destination switching means 122 based on the driving state of the vehicle, thereby connecting the connection destination of the second pump 22 to the first hydraulic oil line P It is switched to either 1 or the second hydraulic oil line P2 (details will be described later as main flow control). The operation state detection means 121 detects, for example, the temperature of the hydraulic oil and the engine speed. The hydraulic oil flow rate control means 120 connects the second pump 22 to the second hydraulic oil line P2 via the connection destination switching means 122 when it is in the high rotation and high temperature operation region of a predetermined value or more. When the hydraulic fluid flow control means 120 is in the other operation region (low rotation region or low temperature region), the second pump 22 is connected to the first hydraulic oil line P1 via the connection destination switching means 122. Let Accordingly, in the high rotation and high temperature operation region, the second pump 22 is disconnected from the first hydraulic oil line P1 and directly connected to the torque converter 2. For this reason, the second pump 22 supplies lower pressure hydraulic oil to the torque converter 2. Accordingly, it is possible to prevent supply of excessive hydraulic oil to the multi-stage transmission 1 in a high rotation and high temperature operation region, and to reduce loss.

Next, the lubricating oil flow rate control means 130 controls the flow rate of the lubricating oil supplied from the torque converter 2 to the lubricating oil circuit of the multi-stage transmission 1 according to the speed stage selected by the shift control means 100. (Details will be described later as lubricant flow control).

[0028] The hydraulic oil discharged from the torque converter 2 is supplied to the lubricating oil circuit of the multi-stage transmission 1 via the lubricating oil line P3. In this lubricating oil line P3, for example, a flow rate adjusting means 131 configured like a throttle valve is provided. The lubricating oil flow rate control means 130 adjusts the flow rate of the lubricating oil flowing through the lubricating oil line P3 according to the speed stage selected by the speed change control means 100. That is, for example, when a high speed stage is selected, the lubricating oil flow rate control means 130 outputs a control signal to the flow rate adjusting means 131 to reduce the lubricating oil flow rate. As a result, the lubricating oil required by the gear combination corresponding to the selected speed stage can be supplied to the lubricating oil circuit of the multi-stage transmission 1 to reduce the loss by preventing excessive lubricating oil supply. it can.

[0029] Hereinafter, a more detailed configuration of the present embodiment will be described with reference to FIGS. First, FIG. 2 is a hydraulic circuit diagram showing an example of the hydraulic device 10 for a multi-stage transmission. As will be described later, the hydraulic apparatus 10 includes a pump unit 20, a hydraulic oil circuit unit 30, a lubricating oil circuit unit 40, and a transmission control unit 50.

[0030] The pump unit 20 includes two oil pumps, that is, a first pump 21 and a second pump 22. Each of the first pump 21 and the second pump 22 is configured as a gear pump, for example. The pumps 21 and 22 each discharge the hydraulic oil sucked from the tank as the drive shaft 23 rotates by the rotational force of the engine 3.

[0031] The hydraulic oil circuit section 30 includes, for example, a flow rate switching valve 31, a main relief valve 32, a secondary relief valve 33, solenoid valves 34 and 36 for adjusting pilot pressure, and pilot pressure relief valves 35, 37, a check valve 38, and the lines P31 to P38. [0032] The main hydraulic oil line P31 is a conduit for supplying hydraulic oil to the transmission control valve group 51. The main hydraulic oil line P31 is connected to a main discharge oil line P21 to which the discharge rocker of the first pump 21 also comes. The main hydraulic oil line P31 is further connected to a branch line P34 that leads to the first outlet force of the flow rate switching valve 31, and the discharge port of the second pump 22 also comes to the inlet of the flow rate switching valve 31. Oil line P22 is connected. Therefore, the hydraulic fluid discharged from the first pump 21 and the second pump 22 can be supplied to the main hydraulic oil line P31. However, as will be described later, only the hydraulic oil from the first pump 21 flows into the main hydraulic oil line P31 when in the predetermined operation region.

[0033] A main relief valve 32 is connected to the main hydraulic oil line P31. The main relief valve 32 adjusts the hydraulic pressure (main hydraulic pressure) of the main hydraulic oil line P31 to a predetermined main relief pressure. The hydraulic oil adjusted to the main relief pressure in the main hydraulic oil line P31 is supplied to the transmission control valve group 51 for selectively operating the eight clutch packs described above.

[0034] In the main relief valve 32, the main relief pressure changes in a plurality of stages in accordance with the norot pressure of the norot pressure line P35 for main pressure control. The pressure in the main hydraulic oil line P31 is reduced by a throttle or the like and supplied to the norot pressure line P35. A pressure relief line P36 extending to the tank is connected to the notlot pressure line P35, and a solenoid valve 34 for adjusting the nolot pressure is provided in the middle of the pressure relief line P36. Further, the pressure relief line P36 is provided with a pilot pressure relief valve 35 for adjusting the pilot pressure to a predetermined pressure.

The solenoid valve 34 opens and closes in response to a control signal from the transmission controller 52, as will be described later. When the solenoid valve 34 is opened, the pilot pressure line P35 is connected to the tank through a throttle for appropriately reducing the hydraulic pressure. As a result, the main relief pressure is adjusted, and the notlot pressure is maintained at a predetermined pressure. On the other hand, when the solenoid valve 34 is closed according to the control signal from the transmission controller 52, the pilot pressure in the pilot pressure line P35 rises and the main relief pressure is set to a low pressure. As a result, the main pressure decreases.

[0036] The auxiliary hydraulic oil line P32 is connected to the excess oil outlet of the main relief valve 32 and the lubricating oil line P41. Connected. A branch line P33 coming from the second outlet of the flow rate switching valve 31 is also connected to the auxiliary hydraulic oil line P32. The auxiliary hydraulic oil line P32 is a conduit for supplying hydraulic oil to a circuit of relatively low pressure such as the torque converter 2 and the lubricating oil circuit 43.

[0037] A secondary relief valve 33 is provided in the secondary hydraulic oil line P32. The auxiliary relief valve 33 adjusts the hydraulic pressure of the secondary hydraulic oil line P32 to a predetermined auxiliary relief hydraulic pressure (a value lower than the main relief pressure) suitable for the hydraulic pressure of the torque converter 2. The hydraulic oil adjusted to the auxiliary relief pressure in the auxiliary hydraulic oil line P32 is supplied to the torque converter 2.

[0038] The flow rate switching valve 31 is configured as, for example, a three-port, two-position hydraulic-nozzle switching valve, and the second pump 22 is connected to either the main hydraulic oil line P31 or the auxiliary hydraulic oil line P32. To switch to. When the flow rate switching valve 31 is switched to the switching position (a), the second pump 22 is connected to the main hydraulic oil line P31 via the line P34. When the flow rate switching valve 31 is switched to the switching position (b), the second pump 22 is connected to the auxiliary operating oil line P32.

[0039] The flow rate switching valve 31 is switched according to the pressure in the pilot pressure line P38 for controlling the hydraulic fluid flow rate. The pilot pressure line P38 is connected via the pilot pressure line P35 and the branch pilot pressure line P37 described above. The pilot pressure line P38 is supplied with the main pressure reduced by a throttle or the like.

[0040] The pilot pressure line P38 is provided with a pilot pressure adjusting solenoid valve 36 and a pilot pressure relief valve 37, respectively. This solenoid valve 36 opens and closes in response to a control signal from the transmission controller 52, similarly to the solenoid valve 34 described above.

[0041] When the solenoid valve 36 is opened, the pilot pressure line P38 is connected to the tank through an appropriate throttle, and the pilot pressure is reduced. As a result, the flow rate switching valve 31 switches to the switching position (a) by the panel force, and connects the second pump 22 to the first hydraulic oil line P31. When the solenoid valve 36 is closed, the pilot pressure in the pilot pressure line P38 increases, and the flow rate switching valve 31 is piled on the panel force and switched to the switching position (b). Thus, the second pump 22 is connected to the second hydraulic oil line P32.

[0042] The check valve 38 is provided upstream of the flow rate switching valve 31 so as to connect the main discharge oil line P21 and the sub discharge oil line P22. This check valve 38 is a sub discharge oil line. Directional force from P22 to main discharge oil line P21 Permits only hydraulic fluid flow and prevents reverse flow. Normally, the check valve 38 is closed because the pressure in the main hydraulic oil line P31 is higher than the pressure in the auxiliary hydraulic oil line P32. When the main pressure decreases, the check valve 38 opens and the hydraulic oil discharged from the second pump 22 is supplied to the main hydraulic oil line P31.

[0043] The configuration of the lubricating oil circuit section 40 will be described. The surplus oil from the auxiliary relief valve 33 is supplied to the lubricating oil line P41 of the lubricating oil circuit section 40 as lubricating oil for the multi-stage transmission 1. The hydraulic oil discharged from the torque converter 2 to the discharge line P4 is supplied to the retarder (wet multi-plate brake) 4 as cooling oil. The hydraulic oil that has passed through the retarder 4 is cooled by the oil cooler 5 and then flows into the lubricating oil line P41.

[0044] The lubricating oil line P41 is provided with a lubricating oil relief valve 41 and a flow path diameter switching valve 42, respectively. The lubricating oil relief valve 41 adjusts the pressure of the lubricating oil to a predetermined pressure. The channel diameter switching valve 42 controls the channel diameter of the lubricating oil line P41 in a plurality of stages. The lubricating oil in the lubricating oil line P41 is supplied to the lubricating oil circuit 43 of the multi-stage transmission 1 after passing through the flow path diameter switching valve 42.

[0045] The flow path diameter switching valve 42 is configured as, for example, a 2-port 2-position hydraulically controlled switching valve, and switches between the switching position (a) and the pilot pressure in the pilot pressure line P42 for flow path diameter control. Switch to / from the switching position (b)!

The pilot pressure line P42 is connected to the main hydraulic oil line P31 via the branch pilot pressure line P37, and supplies the pilot pressure reduced by a throttle or the like to the flow path diameter switching valve 42. The pilot pressure line P42 is provided with a solenoid valve 44 for adjusting the pilot pressure.

The solenoid valve 44 opens and closes in response to a control signal from the transmission controller 52. When the solenoid valve 44 is opened, the pilot pressure line P42 is connected to the tank through an appropriate throttle, and the pilot pressure is maintained at a predetermined value. In this state, the flow path diameter switching valve 42 is switched to the switching position (b) by the panel force, and the flow path diameter of the lubricating oil line P41 is increased.

[0048] When the solenoid valve 44 is closed, the pilot pressure in the pilot pressure line P42 increases, and the flow path The diameter switching valve 42 is piled on the panel force and switched to the switching position (a). At the switching position (a), since the flow path of the flow path diameter switching valve 42 is throttled, the flow path diameter of the lubricating oil line P41 is reduced, and the flow rate of the lubricating oil supplied to the lubricating oil circuit 43 is reduced.

The configuration of the transmission control unit 50 will be described. The transmission control unit 50 includes a transmission control valve group 51, a transmission controller 52 and a force S for controlling the transmission control valve group 51.

[0050] A transmission controller (hereinafter abbreviated as "controller") 52 is configured as, for example, a computer device including a microprocessor, a memory, and the like, and reads and executes a pre-stored program code, which will be described later. Each control process is realized. The controller 52, for example, operates the transmission control valve group 51 in accordance with the driving state of the vehicle or an instruction from the driver, and selects the transmission gear by selectively coupling and releasing the clutch pack. Thereby, an appropriate speed stage is selected.

[0051] As shown in FIG. 3, in the present embodiment, seven speed stages F1 to F7 (the higher the number, the more suitable the speed stage for higher speeds) are prepared just by moving forward. . The relationship between these speed stages and the six forward transmission gears described above is shown in FIG. The circle in Fig. 3 means that the transmission gear has been selected. Further, in the same figure, clutch holding pressure for selecting each transmission gear is also illustrated.

[0052] As shown in FIG. 3, the clutch holding pressures of the first gear and the second gear are much higher than those of the other gears. The first gear and Z or the second gear are selected only in the range of relatively low speed stages below F3, and in the range of relatively high speed stages above F4, the first gear is selected. Neither gear nor second gear is selected. Therefore, the clutch holding pressure required for the multi-stage transmission 1 is relatively high when a relatively low speed stage of F3 or lower is selected, but a relatively high speed stage of F4 or higher is selected. When done, it goes low.

[0053] The controller 52 controls the transmission control valve group 51 to select the speed stage. The operating pressure of the main hydraulic oil line P31, that is, the main relief pressure is selected according to the selected speed stage. The control (main pressure control) is also performed to change to multiple stages.

That is, when the controller 52 selects a relatively low speed stage of F3 or less, the controller 52 sets the main relief pressure to the clutch holding pressure for the first gear and the second gear (36.5 kg / cm2 and 34 kg / The oil pressure is controlled to a relatively high hydraulic pressure (for example, 37.5 kg / cm2) suitable for securing cm2). Controller 52 is suitable for securing the main reef pressure and clutch holding pressure for other gears (18.5 kg / cm2 or less) when a relatively high speed stage of F4 or higher is selected. It is controlled to a relatively low hydraulic pressure (for example, 20.0 kg / cm2).

In order to perform this main relief pressure control, the controller 52 outputs a control signal to the solenoid valve 34 to open or close the solenoid valve 34. As described above, when the solenoid valve 34 is opened or closed, the pilot pressure in the pilot pressure line P35 changes, and the main relief pressure of the main relief valve 32 is adjusted.

The main pressure control will be described with reference to the flowchart of FIG. The controller 52 obtains the currently selected speed stage (S11). Then, the controller 52 determines whether or not the selected speed stage is greater than or equal to a predetermined threshold value Thl (S12). Here, the threshold value Thl is set to F4.

[0057] When selecting a relatively high speed stage of F4 or higher (S12: YES), the controller 52 energizes the solenoid valve 34 to close it (S13). On the other hand, when the controller 52 selects a relatively high speed stage of F3 or less (S12: NO), the controller 52 stops energizing the solenoid valve 34 and opens it (S14).

[0058] When the solenoid valve 34 is closed in S13, the pilot pressure of the main relief valve 32 changes to a predetermined high value, and the main relief pressure (main pressure of hydraulic oil supplied to the transmission) is a predetermined low value. (18.5kg / cm2 or less) is set.

[0059] When the solenoid valve 34 is opened in S14, the pilot pressure of the main relief valve 32 changes to a predetermined low value, and the main relief pressure (main pressure) is set to a predetermined high value (eg, 37.5 kg / cm2). Is done. Thus, the main pressure is controlled according to the selected speed stage. By controlling the main pressure to a value that is always close to the required clutch holding pressure, the problem of loss caused by setting the main pressure higher than necessary is improved.

[0060] The controller 52 controls the flow rate of the working oil flowing through the first hydraulic oil line P31 in addition to the above-described main pressure control (main flow rate control). For this purpose, oil temperature sensors 53 and 54 and an engine speed sensor 55 are connected to the controller 52, respectively.

[0061] One oil temperature sensor 53 is provided in the vicinity of the hydraulic oil inlet of the torque converter 2. Then, the temperature of the hydraulic oil flowing into the torque converter 2 is detected. The other oil temperature sensor 54 is provided in the vicinity of the hydraulic oil inlet of the transmission control valve group 51 and detects the temperature of the hydraulic oil flowing into the transmission control valve group 51. Each of the oil temperature sensors 53 and 54 outputs the oil temperature to the controller 52 as an electric signal. The engine speed sensor 55 detects the speed of the engine 3 and outputs it to the controller 52 as an electrical signal.

FIG. 5 shows a flowchart of the main flow rate control. The controller 52 obtains the oil temperature from each of the oil temperature sensors 53 and 54 (S21), and obtains the engine speed from the engine speed sensor 55 (S22).

The controller 52 determines the driving state of the vehicle based on detection signals from the oil temperature sensors 53 and 54 and the engine speed sensor 55. As shown in the lower side of FIG. 5, the driving state of the vehicle on which the multi-stage transmission 1 is mounted can be classified into a plurality of driving regions A1 to A4.

[0064] The first operation region A1 corresponds to a "predetermined operation region". The first operation region A1 is a high load region in which the engine speed is equal to or higher than a preset predetermined speed Nel and the oil temperature is equal to or higher than a preset predetermined temperature T1.

[0065] The second operating area A2 is an area where the engine oil temperature is Nel or higher and the hydraulic oil temperature is lower than T1. The third operating region A3 is a region where the engine speed is less than Nel and the oil temperature is also less than T1. The fourth operation region A4 is a region where the engine speed is less than Nel and the oil temperature is T1 or more. The third operation region A3 and the fourth operation region A4 can be called, for example, a low load region.

[0066] When the controller 52 determines that the current operation state is within the predetermined operation region A1 (S23: YES), the controller 52 outputs a control signal to the solenoid valve 36 to switch the flow rate switching valve 31 to the switching position ( Switch to b) (S24). As a result, the second pump 22 is connected to the torque converter 2 via the second hydraulic oil line P32. The hydraulic oil discharged from the second pump 22 is directly supplied to the torque converter 2. That is, hydraulic oil from the first pump 21 is supplied to the first hydraulic oil line P31, and hydraulic oil from the second pump 22 is supplied to the second hydraulic oil line P32.

[0067] On the other hand, the controller 52 operates in an operation region (A2, A3, A4 other than the predetermined operation region). When it is determined that the pressure is a force (S23: NO), a control signal is output to the solenoid valve 36 to switch the flow rate switching valve 31 to the switching position (a) (S25). Thereby, the second pump 22 is connected to the first hydraulic oil line P31, and the hydraulic oil from the first pump 21 and the second pump 22 is supplied to the first hydraulic oil line P31.

The controller 52 controls the amount of lubricating oil supplied to the lubricating oil circuit 43 in addition to the main pressure control and main flow control (lubricating oil flow control). Fig. 6 is a flow chart of lubricant flow control.

The controller 52 acquires the selected speed stage (S31), and determines whether or not the selected speed stage is greater than or equal to a preset threshold value Th2 (S32). This threshold Th2 is set to F6.

[0070] When a relatively high speed stage F6 or higher is selected (S32: YES), the controller 52 energizes the solenoid valve 44 to close it, thereby switching the channel diameter switching valve 42 to the switching position (a ) (S33). As a result, the flow path diameter of the lubricating oil line P41 is reduced, and the amount of lubricating oil supplied to the lubricating oil circuit 43 decreases.

[0071] On the other hand, when the controller 52 selects a relatively low speed or medium speed speed less than F6 (S32: NO), the controller 52 stops energization of the solenoid valve 44 and opens the valve, thereby reducing the flow path diameter. The switching valve 42 is switched to the switching position (b) (S34). As a result, the flow path diameter of the lubricating oil line P41 returns to the original value, and the amount of lubricating oil supplied to the lubricating oil circuit 43 increases.

Since the present embodiment is configured as described above, the following effects are obtained. In this embodiment, the main pressure is variably controlled so as to be a pressure corresponding to the clutch holding pressure of the speed stage selected from among the speed stages F1 to F7. Therefore, hydraulic oil can be supplied to the gearbox control valve group 51 with the main pressure corresponding to the clutch holding pressure, preventing the supply of hydraulic oil that is higher than necessary and reducing loss. can do.

In the present embodiment, the hydraulic fluid flow rate of the main hydraulic oil line P31 is controlled by switching the connection destination of the second pump 22 based on the driving state of the vehicle. Therefore, in a high load region of high rotation and high temperature, the second pump 22 can be disconnected from the first hydraulic oil line P31, and the flow rate of hydraulic oil supplied to the transmission control valve group 51 can be reduced. As a result, more hydraulic oil than necessary is supplied to the transmission control valve group 51. It can be prevented and the loss can be reduced.

[0074] In the present embodiment, a plurality of gear pumps of the first pump 21 and the second pump 22 are used to ensure the maximum required flow rate, and the first pump 21 is always connected to the first hydraulic oil line P31, and then Thus, the second pump 22 is used as necessary. Therefore, the hydraulic oil flow rate can be controlled at a lower cost than when a single variable pump is used.

In this embodiment, the flow rate of the lubricating oil supplied to the lubricating oil circuit 43 of the multi-stage transmission 1 is variably controlled in accordance with the selected speed stage. Therefore, it is possible to supply the lubricating oil necessary for the gear combination corresponding to the selected speed stage to the lubricating oil circuit of the multi-stage transmission 1, and to prevent excessive lubricating oil from being supplied, Loss can be reduced.

In the present embodiment, the main pressure control, the main flow rate control, and the lubricating oil flow rate control described above can be executed simultaneously in parallel. Therefore, the loss of hydraulic oil is reduced by the synergistic effect of these controls. be able to. Thereby, fuel consumption and driving performance can be improved.

Note that the present invention is not limited to the above-described embodiment. Those skilled in the art can make various additions and modifications within the scope of the present invention.

Claims

The scope of the claims

[1] A multi-stage transmission hydraulic device (10) for supplying hydraulic oil to a multi-stage transmission (1), wherein the multi-stage transmission (1) includes different clutches for each of a plurality of speed stages (F1-F7). Holding pressure is set,

Pressure adjusting means (111) for adjusting the pressure of hydraulic oil supplied to the multi-stage transmission (1) according to a given control signal;

By giving the control signal to the pressure adjusting means (111) according to the speed stage selected from among the speed stages, the multi-speed shift is performed at a pressure corresponding to the clutch holding pressure of the selected speed stage. And a hydraulic pressure control means (110) for supplying hydraulic oil to the machine (1), and a hydraulic device for a multi-stage transmission.

[2] The pump includes a first pump (21) connected to the multi-stage transmission (1) and a second pump connected to the multi-stage transmission (1) via connection destination switching means (122). And a hydraulic oil flow rate control means (120) for controlling the flow rate of hydraulic oil supplied to the multi-stage transmission (1). Item 4. The hydraulic device for a multi-stage transmission according to Item 1.

[3] The hydraulic oil flow rate control means (120)

Based on the operation state detected by the operation state detection means (121), it is determined whether or not the vehicle is in a predetermined operation region that is set in advance. Disconnect the pump (22) and the multi-stage transmission (1),

3. When the second pump (22) is connected to the multi-stage transmission (1) via the connection switching means (122) when it is determined that the vehicle is in an operation region other than the predetermined operation region. The hydraulic apparatus for multi-stage transmission as described.

[4] Furthermore, a lubricating oil flow rate control means (130) for controlling the supply of lubricating oil to the multi-stage transmission (1) is provided,

The hydraulic device for a multi-stage transmission according to claim 1, wherein the lubricating oil flow rate control means (130) controls an amount of lubricating oil supplied to the multi-stage transmission (1) according to the selected speed stage. .

[5] The pump according to any one of claims 1 to 4, wherein the pump is a gear pump. The hydraulic device for a multi-stage transmission according to one item.

A hydraulic device (10) for a multi-stage transmission for supplying hydraulic oil to a multi-stage transmission (1) having a torque converter (2),

In the multi-stage transmission (1), different clutch holding pressures are set for a plurality of speed stages (F1-F7),

A first pump (21) connected to the multi-stage transmission (1) via a first hydraulic oil line (P1) and discharging hydraulic oil;

Connected to the multi-stage transmission (1) via the first hydraulic oil line (P1) or connected to the torque converter (2) via the second hydraulic oil line (P2), A second pump (22) for discharging

Based on the input control signal, connection destination switching means (122) for connecting the second pump (22) to either one of the first hydraulic oil line (P1) or the second hydraulic oil line (P2). )When,

Pressure adjusting means (111) for adjusting the pressure of the first hydraulic oil line (P1);

When the selected speed stage is a preset low speed control speed stage (F 4 F7), by giving a control signal to the pressure adjusting means (111), 1 When the pressure in the hydraulic oil line (P1) is reduced and the selected speed stage is a preset high speed control speed stage (F1-F3), the pressure adjusting means (111) Hydraulic oil pressure control means (110) for increasing the pressure of the first hydraulic oil line (P1) by giving a control signal;

Driving state detecting means (121) for detecting the driving state;

When the operation state detected by the operation state detection means (121) indicates a predetermined high rotation and high temperature operation region (A1), the second pump ( 22) is connected to the second hydraulic oil line (P2), and the detected operating state indicates an operating region (A2, A3, A4) other than the predetermined high rotation and high temperature region, the connection Hydraulic oil flow rate control means (120) for connecting the second pump (22) to the first hydraulic oil line (P1) via a tip switching means (122);

The hydraulic oil discharged from the torque converter (2) is supplied to the lubricating oil circuit of the multi-stage transmission (1). Lubricating oil line (P3) to supply the road as lubricating oil,

Flow rate adjusting means (131) for adjusting the flow rate of the lubricating oil line (P3);

When the selected speed stage is a preset speed stage (F6, F7), a lubricating oil flowing through the lubricating oil line (P3) is provided by giving a control signal to the flow rate adjusting means (131). Lubricating oil flow rate control means (130) for reducing the amount of

A hydraulic device for a multi-stage transmission, comprising: