JP3563804B2 - Transmission control device - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to a transmission control device mainly used for a vehicle.
[0002]
[Prior art]
Various types of transmissions for vehicles have been put into practical use. For example, JP-A-4-243634 discloses that a V-belt is wound between an input-side pulley and an output-side pulley, and the width of each pulley is adjusted. A belt-type continuously variable transmission has been proposed in which the speed ratio is steplessly controlled by changing the winding radius of the belt by changing the speed.
[0003]
In such a transmission, since it is often required to create a neutral state, the power transmission from the input shaft to the output shaft is turned on in the power transmission path from the input shaft to the output shaft. A clutch that is controlled to be off (a hydraulic operating clutch for starting: hereinafter simply referred to as a starting clutch) is provided. In addition, the starting clutch can change the capacity of the torque that can be transmitted from the input side to the output side by controlling the engagement force. As a result, when starting, the torque capacity is reduced with respect to the input torque, and the input side is slid with respect to the output side, thereby enabling a smooth start. The torque can be directly transmitted to the output side.
[0004]
In the transmission disclosed in the above publication, the control of the engagement force of the starting clutch is performed by a clutch control hydraulic pressure generated by a clutch hydraulic pressure control valve (electromagnetic valve) in accordance with a current supplied to a solenoid. The maximum value of the clutch control hydraulic pressure is usually set to be equal to or higher than the hydraulic pressure required to set a torque capacity capable of transmitting the maximum torque input to the input side of the starting clutch to the output side.
[0005]
Also, since the vehicle is required to be able to travel not only forward but also backward, the power transmission path transmits the power of the input shaft to the output shaft so as to rotate the output shaft in the forward direction. And a reverse path for transmitting the power of the input shaft to the output shaft so as to rotate the output shaft in the reverse direction. Here, in the belt-type continuously variable transmission disclosed in the above publication, a forward path and a reverse path are formed by using planetary gears, and the reverse path includes a ring gear of the planetary gear and a reverse hydraulic actuator (reverse drive). It is set by fixedly holding the brake.
[0006]
Normally, the operating hydraulic pressure of the reverse hydraulic actuator is supplied when the manual valve operated by the driver to the forward or reverse position is operated to the reverse position. If the manual valve is operated to the reverse position, smooth transmission of power in the transmission will be hindered. Therefore, for example, when the forward traveling speed of the vehicle has increased to some extent, even if the manual valve is operated to the reverse position, the supply of the operating oil pressure to the reverse hydraulic actuator is prevented, and the reverse path is not set. Often. Here, in the belt-type continuously variable transmission disclosed in the above-mentioned publication, when the vehicle speed becomes equal to or higher than a predetermined value, the solenoid valve for the reverse inhibitor is closed to close the oil supply path for the operating oil pressure to the reverse brake. Thus, the setting of the reverse route during the forward traveling is prevented.
[0007]
[Problems to be solved by the invention]
However, in order to prevent the setting of a reverse path during forward traveling by the method disclosed in the above-mentioned publication, it is necessary to use a dedicated solenoid valve, and the configuration as a hydraulic device becomes complicated, and the cost tends to increase. is there. In addition, the use of a solenoid valve requires a determination circuit for controlling this operation and a drive circuit for exciting the solenoid, resulting in a problem that the configuration of the electric system becomes complicated.
[0008]
The present invention has been made in view of such a problem, and a control device for a transmission that can reliably prevent the operation of a reverse hydraulic actuator during forward traveling without using a solenoid valve for a reverse inhibitor. It is intended to provide.
[0009]
Means and action for solving the problem
In order to achieve the above object, according to the present invention, a clutch hydraulic pressure control means for setting a clutch control oil pressure for performing engagement control of a starting clutch, and an opening / closing switch for opening / closing a supply oil passage of a working oil pressure to a reverse hydraulic actuator Means (reverse inhibitor) and the clutch control hydraulic pressure Is set higher than a clutch control oil pressure required for the start clutch to transmit the maximum torque input to the input side of the start clutch to the output side (hereinafter, referred to as the maximum clutch pressure for displacement control). When the value is equal to or more than the predetermined value, the opening / closing means closes the supply oil passage of the operating oil pressure to the reverse hydraulic actuator.
[0010]
This control device originally uses the clutch control oil pressure for controlling the engagement of the starting clutch to control the operation of the opening / closing switching means in place of the solenoid valve disclosed in the above publication. Therefore, as compared with the case where a solenoid valve is used, the configuration as a hydraulic device is simplified, and it is advantageous in terms of cost. Then, after the clutch control oil pressure increases from the time of starting the forward movement and becomes greater than or equal to a predetermined value (during forward running), the supply oil passage of the operating oil pressure to the hydraulic actuator for reverse movement is closed by the opening / closing switching means. Therefore, the setting of the reverse power transmission path is prevented.
[0011]
Also, The above specified value Is set higher than the maximum clutch pressure for capacity control, Clutch control oil pressure Maximum clutch pressure for capacity control If it is set in a lower range, only the torque capacity control of the starting clutch can be performed, while if the clutch control oil pressure is set in the range above the predetermined value, opening and closing can be performed while maintaining the torque capacity of the starting clutch at the maximum. Only the switching control of the switching means can be performed. In other words, the start clutch and the reverse inhibitor are independently controlled through the communication control of the two solenoids (the solenoid of the clutch hydraulic control valve and the solenoid of the solenoid valve for the reverse inhibitor). Through the energization control of one solenoid of the hydraulic control valve, the torque capacity control in the starting clutch and the operation control of the reverse inhibitor can be controlled independently.
[0012]
【Example】
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
FIG. 1 schematically shows a belt-type continuously variable transmission CVT having a pulley side pressure control device of the present invention. The belt-type continuously variable transmission CVT includes a metal V-belt mechanism 10 disposed between an input shaft 1 and a counter shaft 2 and a planet disposed between the input shaft 1 and a drive-side movable pulley 11. It is composed of a gear type forward / reverse switching mechanism 20 and a starting clutch 5 disposed between the counter shaft 2 and an output-side member (differential mechanism 8 and the like). The continuously variable transmission CVT is used for a vehicle, the input shaft 1 is connected to an output shaft of an engine ENG via a coupling mechanism CP, and the power transmitted to the differential mechanism 8 is transmitted to left and right wheels. .
[0013]
The metal V-belt mechanism 10 is wound around a drive-side movable pulley 11 provided on the input shaft 1, a driven-side movable pulley 16 provided on the counter shaft 2, and between the pulleys 11 and 16. And a metal V-belt 15.
The drive-side movable pulley 11 includes a fixed pulley half 12 rotatably disposed on the input shaft 1, and a movable pulley half 13 axially movable relative to the fixed pulley half 12. . A drive-side cylinder chamber 14 is formed on the side of the movable pulley half 13 so as to be surrounded by a cylinder wall 12a connected to the fixed pulley half 12, and is provided in the drive-side cylinder chamber 14 via an oil passage 39a. The hydraulic pressure supplied causes a side pressure to move the movable pulley half 13 in the axial direction.
[0014]
The driven-side movable pulley 16 includes a fixed pulley half 17 fixedly mounted on the counter shaft 2 and a movable pulley half 18 that is movable relative to the fixed pulley half 17 in the axial direction. A driven cylinder chamber 19 is formed on the side of the movable pulley half 18 so as to be surrounded by a cylinder wall 17a connected to the fixed pulley half 17, and is provided in the driven cylinder chamber 19 via an oil passage 39b. The hydraulic pressure supplied causes a side pressure to move the movable pulley half 18 in the axial direction.
Therefore, by appropriately controlling the hydraulic pressure supplied to the cylinder chambers 14 and 19, an appropriate pulley side pressure that does not cause slippage of the belt 15 is set, and the pulley width of the pulleys 11 and 16 is changed. As a result, the winding ratio of the V-belt 15 can be changed to change the gear ratio steplessly.
[0015]
The planetary gear type forward / reverse switching mechanism 20 is a ring gear that can be fixedly held by a sun gear 21 coupled to the input shaft 1, a carrier 22 coupled to the fixed pulley half 12, and a reverse brake (reverse hydraulic actuator) 27. 23, and a forward clutch 25 capable of connecting the sun gear 21 and the ring gear 23. When the forward clutch 25 is engaged, all the gears 21, 22, and 23 rotate integrally with the input shaft 1, and the drive pulley 11 is driven in the same direction (forward direction) as the input shaft 1 (that is, forward). Power transmission path is set). When the reverse brake 27 is engaged, the ring gear 23 is fixed and held, so that the carrier 22 is driven in the direction opposite to that of the sun gear 21, and the drive pulley 11 is moved in the direction opposite to the input shaft 1 (reverse direction). (I.e., a reverse power transmission path is set).
[0016]
The starting clutch 5 is a clutch that controls power transmission between the counter shaft 2 and the output-side member. When engaged, power can be transmitted between the two, and by controlling the engagement force, the starting clutch 5 is connected to the input side. The torque transmission capacity (torque capacity) with the output side can also be controlled. For this reason, when the starting clutch 5 is engaged, the engine output shifted by the metal V-belt mechanism 10 is transmitted to the differential mechanism 8 via the gears 6a, 6b, 7a, 7b. (Not shown) and transmitted. When the starting clutch 5 is released (torque capacity is zero), this power cannot be transmitted, and the transmission is in a neutral state. The engagement control of the starting clutch 5 is performed by a starting clutch control valve 75 that is operated in response to a signal from the controller 70. The start clutch control valve 75 controls the operating oil pressure (start clutch signal pressure PSC) supplied to the start clutch 5 via the oil passages 31a and 31b, and controls the engagement of the start clutch 5. The specific configuration of the control valve 75 will be described later.
[0017]
The controller 70 receives an engine speed Ne signal and an engine intake negative pressure PB signal from an electronic control unit ECU that controls the operation of the engine ENG, and further receives a signal from an air conditioner operation detector 76 that detects the operation of the air conditioner AC. A detection signal is sent from a shift range position detector 77 that detects a shift range position based on the detection signal and the shift lever position ATP.
[0018]
On the other hand, the control of the hydraulic pressure supplied to the drive-side and driven-side cylinder chambers 14 and 19 is performed by a pulley-side pressure control valve 40 and a shift control valve 50 that are operated in response to a control signal from a controller 70. Here, the pulley side pressure control valve 40 includes a high pressure regulator valve 41, a low pressure regulator valve 43, a high / low pressure control valve 45, and a high pressure control valve 47 shown in FIG. A shift control valve 51 and a shift valve 53 are provided. The specific configuration of these valves will be described in the following description of the control device.
[0019]
A control device for the belt-type continuously variable transmission CVT having the above-described configuration will be described with reference to FIGS. 2 and 3. 2 and 3 together constitute one hydraulic circuit, and in both figures, the oil paths indicated by (1), (2), and (3) are connected to each other. Further, in each of the drawings, an x mark means that the portion is connected to the drain.
The oil discharged from the hydraulic pump 30 is supplied to the high-pressure regulator valve 41 via the oil passage 32 and to the reducing valve 58 via the oil passage 36. In the reducing valve 58, a line pressure PMOD having a substantially constant hydraulic pressure is generated, and the hydraulic oil having the line pressure is supplied to the high / low pressure control valve 45 via the oil passages 37a, 37b, 31a, and 31c. It is supplied to the control valve 51, the starting clutch control valve 75 and the manual valve 61.
[0020]
The high / low pressure control valve 45 has a linear solenoid 45a. The current supplied to the linear solenoid 45a is controlled, and the pressing force acting on the spool 45b from the linear solenoid 45a is controlled, so that the high / low pressure control valve 45 is supplied from the oil passage 37a. The line pressure PMOD is adjusted, and a control back pressure PHLC corresponding to the pressing force is supplied to the oil passages 35a and 35b. This control back pressure PHLC is supplied to the right end oil chamber 43b of the low-pressure regulator valve 43 via the oil passage 35a, and acts to press the spool 43a to the left. The control back pressure PHLC is supplied to the right end oil chamber 47b and the first intermediate oil chamber 47c of the high pressure control valve 47 via the oil passage 35b, and acts to press the spool 47a leftward and rightward, respectively. I do.
[0021]
The high-pressure regulator valve 41 regulates the operating oil pressure supplied from the pump 30 via the oil passage 32, and supplies the high-side pressure control pressure PH to the oil passages 33a and 33b. The high-side pressure control pressure PH is supplied to the shift valve 53 via an oil passage 33a, and is also supplied to a low-pressure regulator valve 43 via an oil passage 33b. Further, the high-side pressure control pressure PH branches off from the oil passage 33a and is supplied to an oil passage 33c connected to a left end oil chamber 47d of the high pressure control valve 47.
[0022]
An oil passage 66 connected to the reverse inhibitor valve 63 is connected to the second intermediate oil chamber 47e of the high-pressure control valve 47. The high-pressure control valve 47 is connected to a control back pressure PHLC supplied to the right end oil chamber 47b and the first intermediate oil chamber 47c and a second starting clutch signal pressure PSC2 to the second intermediate oil chamber 47e via an oil passage 66 (for this, (Described later) is supplied, the position of the spool 47a is controlled by this signal pressure, the high-side pressure control pressure PH supplied from the oil passage 33c is adjusted, and the right end oil of the high-pressure regulator valve 41 is controlled via the oil passage 33d. A back pressure is supplied to the chamber 41b.
[0023]
The low-pressure regulator valve 43 receives the control back pressure PHLC, regulates the high-side pressure control pressure PH supplied from the oil passage 33b, and supplies the low-side pressure control pressure PL to the oil passage. The low side pressure control pressure PL is supplied to the shift valve 53 via oil passages 34 a and 34 b branched from the oil passage 34.
[0024]
The relationship between the control back pressure PHLC created by the high / low pressure control valve 45 and the high and low side pressure control pressures PH and PL set by the high pressure regulator valve 41, the high pressure control valve 47 and the low pressure regulator valve 43 is shown in FIG. It becomes like the graph shown in. However, the high-side pressure control pressure PH is switched in two stages in accordance with the driving situation (the switching mechanism will be described later), and the first high-side pressure control pressure PH1 indicated by a solid line in this figure is generally the gear ratio control. The second high-side pressure control pressure PH2 (<PH1) indicated by a dotted line in the figure is generally set at the time of normal running where the frequency of the gear ratio control is low (however, as will be described later). This is set only for running). Note that the low-speed pressure control pressure PL is constant as a minimum required hydraulic pressure for preventing the slippage of the belt regardless of the running condition.
[0025]
The shift control valve 51 has a linear solenoid 51a, and a current supplied to the linear solenoid 51a is controlled, and a pressing force acting on the spool 51b from the linear solenoid 51a is controlled to be supplied from the oil passage 37b. The line pressure PMOD is adjusted, and a shift control pressure PSV corresponding to the pressing force is supplied to the oil passage 38. This shift control pressure PSV is supplied to the left end oil chamber 53b of the shift valve 53, and acts to press the spool 53a rightward.
[0026]
The shift valve 53 controls to appropriately distribute and supply the high and low side pressure control pressures PH and PL to the drive side and driven side cylinder chambers 14 and 19 via the oil passages 39a and 39b according to the position of the spool 53a. As shown in detail in FIG. 4, the spool 53a receives the shift control pressure PSV on the left end face (pressure receiving area A3) and is pressed rightward while the spool 53a is pressed from the oil passage 37b on the right end face (pressure receiving area A1). The line pressure PMOD is received via the branched oil passage 37c, and is pushed to the left. The hydraulic pressure in the drive-side cylinder chamber 14 (drive-side pressure PDR is received on the right side surface of the intermediate portion (pressure receiving area A2) via a drive-side feedback oil path 39c branched from an oil path 39a connected to the drive-side cylinder chamber 14. The oil pressure (driven side pressure) in the driven side cylinder chamber 19 is pushed to the left, and on the left side surface (pressure receiving area A2) of the intermediate portion via a driven side feedback oil path 39d branched from an oil path 39b connected to the driven side cylinder chamber 19. Upon receiving the PDN, the spool 53a is pressed rightward, so that the spool 53a balances the force PMOD × A1 + PDR × A2 for pushing it leftward and the force PSV × A3 + PDN × A2 for pushing it rightward. Position.
[0027]
Here, when the state where both forces are balanced is expressed by an equation,
PMOD x A1 + PDR x A2 = PSV x A3 + PDN x A2 ... (1)
Becomes
If you transform this,
PMOD × A1 + (PDR−PDN) × A2 = PSV × A3 (2)
It becomes.
As can be seen from equation (2) and FIG. 6, the differential pressure ΔP = PDR−PDN between the drive side pressure PDR and the driven side pressure PDN is proportional to the shift control pressure PSV. For this reason, if one of the drive side pressure PDR and the driven side pressure PDN is set to the low side pressure control pressure PL, the other has an increase in proportion to the low side pressure control pressure PL in proportion to the shift control pressure PSV. Pressure can be set.
[0028]
The starting clutch control valve (clutch oil pressure control means) 75 has a linear solenoid 75a, the current supplied to the linear solenoid 75a is controlled, and the pressing force acting on the spool 75b from the linear solenoid 75a is controlled. The line pressure PMOD supplied from the passage 31a is regulated, and the starting clutch signal pressure PSC corresponding to the pressing force is supplied to the oil passage 31b and the oil passages 31c and 31d branched therefrom. The oil passage 31b is connected to the starting clutch 5 as described above, and the starting clutch signal pressure PSC controls the engagement of the starting clutch 5. The oil passages 31c and 31d supply the starting clutch signal pressure PSC to the left end oil chamber 63b and the first intermediate oil chamber 63c of the reverse inhibitor valve 63.
[0029]
Here, the starting clutch signal pressure PSC output from the starting clutch control valve 75 is proportional to the current I supplied to the solenoid 75a, as shown in FIG. The first starting clutch signal pressure PSC1 having a pressure in the range of the clutch pressure PSC MAX, the first clutch signal pressure PSC MAX for capacity control, and the second clutch signal pressure PSC having a pressure larger than the operation start oil pressure PR (> PSC MAX) of the reverse inhibitor valve 63. The second starting clutch signal pressure PSC2 is classified into a second starting clutch signal pressure PSC2 and a third starting clutch signal pressure PSC3 having a predetermined pressure in a range larger than the displacement control maximum clutch pressure PSC MAX and smaller than the operation start oil pressure PR. The first start clutch signal pressure PSC1 is used as a hydraulic pressure for controlling the engagement of the start clutch 5, and the start clutch 5 performs torque capacity control according to the magnitude of the first start clutch signal pressure PSC1. It should be noted that the torque capacity of the starting clutch 5 that has been supplied with the first starting clutch signal pressure PSC1 equal to the maximum clutch pressure PSC MAX for capacity control is set to a capacity that can directly transmit the maximum torque input to the input side to the output side. It is to be set.
[0030]
Further, the second start clutch signal pressure PSC2 is used as a hydraulic pressure for fixing the torque capacity of the start clutch 5 to the maximum, and also as an operation control oil pressure for the reverse inhibitor valve 63. Further, the third starting clutch signal pressure PSC3 is used only as a hydraulic pressure for fixing the torque capacity of the starting clutch 5 to the maximum. As can be seen from this, the first start clutch signal pressure PSC1 is used when the vehicle starts (both forward and backward), and the second start clutch signal pressure PSC2 is used during normal forward running. Further, the third starting clutch signal pressure PSC3 is used during normal reverse running.
[0031]
The manual valve 61 is connected to a shift lever of a driver's seat (not shown) via a control cable, and is operated by a manual operation of a driver. There are six manual operation positions, P, R, N, D, S, and L, and the spool 61a of the manual valve 61 is moved to the corresponding position shown in accordance with the operation position. The drawing shows a state in which the spool 61a is at the N (neutral) position. The first central oil chamber 61 b of the manual valve 61 is connected to the forward clutch 25 via an oil passage 65. The second central oil chamber 61c of the manual valve 61 is connected to a reverse inhibitor valve 63 via an oil passage 67. The reverse inhibitor valve 63 is connected to an oil passage 68 to which the oil passage 67 can be connected and which is connected to the reverse brake 27.
[0032]
When the spool 61a is at the P and N positions, the manual valve 61 connects both the oil passage 65 and the oil passage 67 to the drain. Therefore, neither the forward clutch 25 nor the reverse brake 27 is engaged. When the spool 61a is at the D, S, or L position, the oil passage 67 is connected to the drain, and the line pressure PMOD supplied from the oil passage 31c is supplied to the oil passage 65. Therefore, the reverse brake 27 does not engage, and the forward clutch 25 engages. Further, when the spool 61a is at the R position, the oil passage 65 is connected to the drain, and the line pressure PMOD supplied from the oil passage 31c is supplied to the oil passage 67. Therefore, the forward clutch 25 is not engaged, and the reverse brake 27 is controlled to be engaged / disengaged by the operation of the reverse inhibitor valve 63 described below.
[0033]
In the reverse inhibitor valve (open / close switching means) 63, the line pressure PMOD is supplied to the right end oil chamber 63c via the oil passage 31c, and the spool 63a is pressed leftward by the line pressure PMOD. When the first start clutch signal pressure PSC1 or the third start clutch signal pressure PSC3 is supplied to the left end oil chamber 63b (during start or reverse running), the spool 63a is located at the left movement position and the oil passage 67 The road 68 is communicated. Thus, when the spool 61a of the manual valve 61 is at the R position, the reverse brake 27 is engaged. The reverse inhibitor valve 63 is connected to an oil passage 66 connected to the second central oil chamber 47e of the high-pressure control valve 47. When the spool 63a is moving left, the oil passage 66 is drained. Connect.
[0034]
On the other hand, when the second start clutch signal pressure PSC2 is supplied to the left end oil chamber 63b (during forward running), the spool 63a is located at the right movement position, shuts off the oil passage 67 and the oil passage 68, and Road 68 is connected to drain. As a result, even if the spool 61a of the manual valve 61 is erroneously operated to the R position, the reverse brake 27 is not engaged and the transmission of reverse power during forward traveling is reliably prevented. You.
[0035]
Further, at this time, the oil passage 66 communicates with the oil passage 31d, and the second starting clutch signal pressure PSC2 is supplied to the second central oil chamber 47e of the high-pressure control valve 47, so that the force pushing the spool 47a rightward increases. Then, the back pressure supplied to the right end oil chamber 41b of the high pressure regulator valve 41 decreases. Therefore, the first high-side pressure control pressure PH1 that has been set so far is switched to the second high-side pressure control pressure PH2. Thus, the oil pump 30 increases the second high-side pressure control pressure PH2 lower than the first high-side pressure control pressure PH1 to be generated at the time of starting when the speed ratio control is high when the vehicle is traveling forward when the speed ratio control is low. If this occurs, it is sufficient, and the load on the oil pump 30 is reduced accordingly. Therefore, the engine load can be reduced, and the fuel efficiency can be improved.
[0036]
In the control device configured as described above, if the start clutch 5 is engaged and the forward clutch 25 or the reverse brake 27 is engaged, the vehicle can run and the control hydraulic pressure PSV is reduced. If the control is performed to control the position of the spool 53a of the shift valve 53, the shift control can be performed by controlling the hydraulic pressure in each of the cylinders 14 and 19.
[0037]
In the above-described embodiment, the reverse inhibitor valve 63 is operated (the second clutch signal pressure PSC2 is output to the starting clutch control valve 75) during forward running regardless of the vehicle speed. In, for example, a vehicle speed sensor for detecting the vehicle speed may be provided, and only when the detected vehicle speed is equal to or higher than a predetermined value, the start clutch control valve 75 may output the second start clutch signal pressure PSC2.
Further, in the above embodiment, the case where the control device of the present invention is applied to a belt-type continuously variable transmission has been described. However, the present control device can be applied to a transmission other than this transmission.
[0038]
【The invention's effect】
As described above, in the present invention, when the clutch control oil pressure for performing the engagement control of the starting clutch is equal to or more than the predetermined value, the opening and closing switching means (reverse inhibitor) supplies the operating oil pressure to the reverse hydraulic actuator. The control device is configured so that is closed. That is, in this control device, the operation control of the opening / closing switching means is originally performed using the clutch control oil pressure for controlling the engagement of the starting clutch. Therefore, it is not necessary to use a solenoid valve as the reverse inhibitor, so that the configuration as the hydraulic device can be simplified and the cost can be reduced. Then, after the clutch control oil pressure increases from the start of forward running and becomes equal to or more than a predetermined value (during forward running), it is possible to reliably prevent the setting of the reverse power transmission path.
[0039]
Here, if the predetermined value is set higher than the clutch control oil pressure required for the starting clutch to transmit the maximum torque input to the input side of the starting clutch to the output side, one solenoid (clutch Through the energization control of the solenoid of the hydraulic control means, the torque capacity control in the starting clutch and the operation control of the reverse inhibitor can be independently performed.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing a configuration of a belt-type continuously variable transmission including a control device of the present invention.
FIG. 2 is a hydraulic circuit diagram showing the control device.
FIG. 3 is a hydraulic circuit diagram showing the control device.
FIG. 4 is an enlarged view of a shift valve used in the control device.
FIG. 5 is a graph showing a low side pressure and a high side pressure control pressure set in the control device.
FIG. 6 is a graph showing an output differential pressure from the shift valve.
FIG. 7 is a graph showing a starting clutch control pressure output from a starting clutch control valve used in the control device.
[Explanation of symbols]
1 input shaft
2 Counter axis
5 Start clutch
10. Metal V-belt mechanism
11 Movable pulley on drive side
15 Metal V belt
16 Driven side pulley
20 Forward / backward switching mechanism
40 Pulley side pressure control valve
41 High pressure regulator valve
43 Low pressure regulator valve
45 High / low pressure control valve
47 High pressure control valve
50 Shift control valve
51 Shift control valve
53 shift valve
58 reducing valve
63 Reverse Inhibitor Valve
70 Controller
75 Start clutch control valve

Claims (1)

A forward path for transmitting the power of the input shaft to the output shaft so as to rotate the output shaft in the forward direction, and the power of the input shaft arranged in parallel with the forward path and rotating the output shaft in the backward direction. A power transmission path comprising a reverse path for transmitting to the output shaft,
A starting hydraulically actuated clutch disposed in the power transmission path to control power transmission from the input shaft to the output shaft;
A transmission having a reverse hydraulic actuator for setting the reverse path,
Clutch hydraulic pressure control means for setting a clutch control hydraulic pressure for performing engagement control of the starting hydraulically actuated clutch,
Opening and closing switching means for opening and closing the supply oil passage of the working oil pressure to the reverse hydraulic actuator,
A predetermined clutch control oil pressure that is set higher than the clutch control oil pressure required for the starting hydraulically operated clutch in order to transmit the maximum torque input to the input side of the starting hydraulically operated clutch to the output side. A transmission control device, wherein when the value is equal to or more than a value, the opening / closing switching means closes a supply oil path of operating hydraulic pressure to the reverse hydraulic actuator.

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