JPS6357951A - Controller for continuously variable transmission - Google Patents

Abstract

PURPOSE:To certainly prevent the selection of the torque transmission in a continuously variable transmission in the retreat direction, simplifying the constitution of the captioned device, by constituting the captioned device so that the hydraulic pressure of a pressure adjusting valve is lowered when the erroneous retreat range is selected during the advance traveling. CONSTITUTION:The captioned device is constituted so that the hydraulic pressure adjusted by a pressure adjusting valve is lowered when the erroneous retreat range is selected during the advance traveling. Therefore, a hydraulic clutch 21 is set into the cut-off state, namely to the state for cutting off the transmission of the engine torque to an advance/retreat selecting mechanism 20, and the shift actuator of the advance/retreat selecting mechanism 20 stops the selecting operation. Therefore, the continuously variable transmission does not select the torque transmission to the retreat direction, accompanied with the range selection. Further, the pressure adjusting valve originally adjusts the hydraulic pressure supplied into the hydraulic clutch 21 and is not specially installed, and the constitution of the controller can be made simple.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a control device for a continuously variable transmission installed in a vehicle.

(Prior Art) Conventionally, as a continuously variable transmission system for vehicles, a primary pulley and a secondary pulley each having a variable effective radius are provided on a pair of mutually parallel axes on an engine torque transmission system, and both A V-belt is wound between the bobbins, and the effective radius of both bobbins is changed relative to each other in opposite directions, thereby continuously changing the gear ratio of the output rotational speed to the input rotational speed. Are known.

In such a continuously variable transmission, the means for switching between forward and reverse is provided with two clutches, one for forward and one for reverse, and the means for switching between forward and reverse is performed by switching on/off of these two clutches ( For example, JP-A-59-77
For example, Japanese Patent Laid-Open No. 51-334 (see Japanese Patent Laid-Open No. 156) and a mechanism in which forward and backward switching is performed by switching gear meshing by a forward/backward switching mechanism provided on the torque transmission system.
(See Publication No. 22). In the latter case, when the gear engagement is switched in the forward/reverse switching mechanism, that is, when the forward/reverse switching mechanism is switched, the engine torque is transmitted to the forward/reverse switching mechanism using a hydraulic clutch. .

(Problem to be Solved by the Invention) Incidentally, while the vehicle is moving forward, the driver may accidentally switch the shift lever to the reverse range. In order to ensure safety, it is required to prevent the switch from switching in either direction.

In order to meet this request, a special valve called a reverse inhibitor valve is provided in the hydraulic circuit of the W control device of the continuously variable transmission, as disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 59-77156. something is known.

However, in this case, there is a problem that the arrangement of the valves complicates the configuration of the hydraulic circuit, making the control device large and expensive.

The present invention has been made in view of the above, and its purpose is particularly to improve the configuration of a control device of a continuously variable transmission equipped with a forward/reverse switching mechanism as a means for switching between forward and reverse modes. has been improved to simplify the control device while reliably preventing torque transmission in the continuously variable transmission from switching to the reverse direction when the shift lever is mistakenly selected to the forward range during 1yl forward driving. It is to make it possible.

(Means for solving the problem) In order to achieve the above object, the solving means of the present invention provides a continuously variable transmission equipped with a forward/reverse switching mechanism on a torque transmission system in which engine torque is transmitted via a hydraulic clutch. As a control device of the machine, the shift actuator of the forward/reverse switching mechanism is operated by the hydraulic pressure regulated by the pressure regulating valve for the hydraulic clutch, and the pressure regulating valve is set to the reverse range during forward travel. The configuration is such that the oil pressure is lowered when selected.

(Function) With the above configuration, in the present invention, when the reverse range is incorrectly selected during forward running, the hydraulic pressure regulated by the pressure regulating valve decreases, and the hydraulic clutch is in the disengaged state, that is, the forward/reverse switching of the engine torque is performed. As well as becoming in a state where transmission to the mechanism is cut off.

The shift actuator of the forward/reverse switching mechanism is in a state where the switching operation is stopped, so that in the continuously variable transmission, torque transmission is not switched to the reverse direction upon range selection.

Furthermore, the pressure regulating valve is originally intended to regulate the hydraulic pressure supplied to the hydraulic clutch, and is used to prevent torque transmission in the continuously variable transmission from switching to the reverse direction when the reverse range is selected during forward driving. Since it is not specially provided to prevent this, the configuration of the control device can be simplified.

(Example) Embodiments of the present invention will be described below based on the drawings.

FIG. 1 shows a continuously variable transmission for a vehicle according to the present invention, in which 1 is a fluid coupling, and the fluid coupling 1 is connected to an engine output shaft 2.
The pump impeller 3 is connected to a pump impeller 3, and a turbine impeller 4 is provided facing the pump impeller 3. The turbine impeller 4 is connected to and supported by an output shaft 5. Further, the fluid coupling 1 has an engine output 'l which is its input shaft.
A lock-up clutch 6 is provided that directly connects the '1l12 and the output shaft 5.

Further, 7 is a primary pulley provided on the rotating shaft 8 located on the same axis as the output shaft 5 of the fluid coupling 1 and the engine output shaft 2, and 9 is provided on the rotating shaft 10 corresponding to the primary pulley 7. There is a V between the primary pulley 7 and the secondary pulley 9.
A belt 11 is wrapped around it. The primary pulley 7 includes a fixed conical plate 12 fixed to the rotating shaft 8, a movable conical plate 13 facing the fixed conical plate 12 and provided on the rotating shaft 8 so as to be movable back and forth, and the movable conical plate 13. The movable conical plate 13 is fixed to the conical plate 12 by supplying and discharging pressure oil to and from the hydraulic chamber 14.
By moving the belt forward and backward, the effective radius of belt winding can be variably controlled.

On the other hand, the secondary pulley 9 includes a fixed conical plate 15 fixed to the rotating shaft 10, a movable conical plate 16 facing the fixed conical plate 15 and provided so as to be movable above the rotating shaft 10, and a movable conical plate 16. The upper temperature movable conical plate 16 receives the hydraulic pressure in the hydraulic chamber 17 so that the tension of the V bell (11 is maintained constant). It moves forward and backward on the rotating shaft 10. Therefore, the effective belt winding radius of the secondary pulley 9 is equal to the belt winding effective radius of the primary pulley 7 while maintaining the tension of the belt 11 constant. Therefore, by changing the effective radius of the primary pulley 7, the gear ratio is configured to change steplessly and continuously.The torque transmitted to the secondary pulley 9 is transmitted from the rotating shaft 10 supporting the secondary pulley 9 via the gear mechanism 18 to the transmission output shaft 19, and from the output shaft 19 to the driving wheels.

Further, on the torque transmission path between the fluid coupling 1 and the primary pulley 7, there is a forward/backward switching mechanism 20 that switches between forward and backward, and a forward/backward switching mechanism 20 that switches between forward and backward switching, and a forward/backward switching mechanism 20 that disconnects torque transmission from the fluid coupling 1 to the forward/backward switching mechanism 20. A hydraulic clutch 21 in contact is provided. The forward/backward switching mechanism 20 includes a sleeve member 22 that slides by the operation of a shift actuator 42 (described later), and when the sleeve member 22 is moved to the left in the figure, engine torque is transmitted via the hydraulic clutch 21. is transmitted directly to the rotating shaft 8 supporting the primary pulley 7, that is, in the forward rotational direction, while when the sleeve member 22 is moved to the right in the figure, the engine torque transmitted via the hydraulic clutch 21 is transmitted to the idle gear mechanism 23. It is configured to transmit the signal in the backward rotational direction to the rotating shaft 8 via the rotary shaft 8.

A hydraulic control device for controlling the operation of the continuously variable transmission is shown in FIG. In FIG. 2, 30 is an oil pump, and 31 is a secondary pressure valve connected to the oil pump 30 via an oil passage 32. It has a spring 31c compressed into a spring chamber 31b and a hydraulic chamber 31d communicated with an oil passage 32.
Hydraulic pressure regulated by a secondary pressure solenoid 33 is applied to 1b as a pilot pressure.

Therefore, the secondary pressure valve 31 is operated by the spring 31c.
The spool 31a moves left and right to open and close according to the force relationship between the sum of the urging force and the pilot pressure and the oil pressure in the hydraulic chamber 31d, thereby increasing the oil pressure in the oil passage 32, that is, the discharge pressure of the oil pump 30. The pressure in the oil passage 32 is regulated at a constant level, and the oil pressure in the oil passage 32 is variably controlled by the secondary pressure solenoid 33.

Further, 34 is a clutch pressure valve connected to the secondary pressure valve 31 via an oil passage 35, and like the secondary pressure valve 31, the clutch pressure valve 34 is connected to a spool 34a and one end of the spool 34a. Spring chamber 34
It has a spring 34c compressed in the spring 34c and a hydraulic pressure u34d communicated with the oil passage 35, and the sum of the biasing force of the spring 34c and the pilot pressure applied to the spring chamber 34 from the clutch pressure solenoid 36 and the hydraulic pressure. By moving the spool 34a from side to side to open and close in relation to the oil pressure in the chamber 34d, the oil pressure in the oil passage 35 is regulated at a constant level. The hydraulic pressure is variably controlled by the clutch pressure solenoid 36.

Oil passage 35 whose pressure is regulated by the clutch pressure valve 371
Pressure oil inside is supplied to the hydraulic clutch 21 via an oil passage 37 and to a manual valve 39 via an oil passage 38. The manual valve 39 has a spool 39a that is interlocked with the shift lever 1 to the lever (not shown), and the manual valve 39 has two oil passages 40.
．． A shift I-actuator 42 of the forward/backward switching mechanism 20 is connected via the forward/backward switching mechanism 41 . The shift actuator 42 has two hydraulic chambers 42c and 42d @H partitioned by a piston 42b in a cylinder 42a, and oil passages 40 and 41 from the manual valve 39 communicate with the eight hydraulic chambers 42c and 42d, respectively. has been done. When the manual valve 39 is in the D (drive) range position, the oil passage 38 and the oil passage 40 are communicated with each other in the three manual valves, and the oil passage 41 is drained, so that the shift actuator 42 In the state shown in the upper half of the figure, when the forward/reverse switching mechanism 20 is switched to the forward direction and the manual valve 39 is in the R (reverse) range position, the oil passages 38 and 41 communicate with each other in the three manual valves. By draining the oil passage 40 and draining the oil passage 40, the shift actuator 42
The state shown in the lower half of the figure is reached, and the forward/reverse switching mechanism 20 is configured to be switched to reverse. The hydraulic chamber 42c of the shift actuator 42 is equipped with a spring 42e for switching the forward/backward switching mechanism 20 to the forward direction in the event of a failure of the hydraulic control device.

In addition, an oil passage 37 between the oil pump 30 and the hydraulic clutch 21 supplies pressure oil to the hydraulic clutch 21.
A clutch control valve 43 for switching and controlling the discharge is provided, and the clutch control valve 43 is connected to the spool 43a.
, a spring 43C compressed into a spring chamber 43b at one end of the spool 43a, and a hydraulic chamber 43 formed at a portion adjacent to the spring chamber 43b and at the other end of the spool 43a.
d, 43e. The above clutch control valve 4
The hydraulic chamber 43e at the other end of the spool 43a of No. 3 is communicated with the upstream side of the clutch control valve 43 of the oil passage 37, and the other hydraulic chamber 43d and spring chamber 43b of the clutch control valve 43 are connected to the oil passage 44 or the other end of the spring chamber 43b, respectively. 45 into the cylinder 42a of the shift actuator 42.

The ports 44a, 45a of both sleeves 44, 45 to the cylinder 42a are connected to the piston 42 in the cylinder 42a.
When b is in either the D range position or the R range position, the pressure oil is supplied to the expanded hydraulic chamber of the two hydraulic pressures v42c and 42d (when in the D range, the hydraulic chamber 42C and the R range When the piston 42b is moving between the D range position and the R range position (when the piston 42b is moving between the D range position and the R range position (at the time of forward/backward switching)), it opens into separate hydraulic chambers 42C and 42d, or One side is closed by the piston 42b. When the shift actuator 42 is in a non-operating state at the D range position or the R range position, the clutch control valve 43 is operated by the hydraulic chambers 43d and 43d, and the pressure oil is supplied from the shift actuator 42 to the hydraulic chambers 43d and 43 through oil passages 44 and 45, respectively. Spring chamber 43
When supplied to b, both chambers 43d, 43
The spool 43 is moved by the hydraulic pressure of b and the biasing force of the spring 43C.
a is the position where the oil passage 37 shown in the upper half of the figure is communicated to supply pressure oil to the hydraulic clutch 21, that is, the position where the hydraulic clutch 21 is connected, and the shift actuator 42 performs a forward and reverse switching operation. (When the piston 42b moves between the D range position and the R range position in the cylinder 42a) The spool 43a is moved by the hydraulic pressure of the hydraulic chamber 43e.
interrupts the communication of the oil passage 37 shown in the lower half, and the hydraulic clutch 2
The hydraulic clutch 21 is temporarily switched to a position where the pressure oil of No. 1 is discharged, that is, a position where the hydraulic clutch 21 is disengaged.

On the other hand, the pressure oil from the oil pump 30 whose pressure is regulated by the secondary pressure valve 31 is delivered to the hydraulic chamber 17 of the secondary pulley 9 via the oil passage 46 and to the hydraulic chamber 14 of the primary pulley 7 via the oil passage 47. Each is supplied.

The oil passage 47 is provided with a gear ratio control valve 48 that controls the gear ratio by switching between supplying and discharging pressure oil to the hydraulic chamber 14 of the primary pulley 7. Four gear ratio fixing valves are interposed between the two hydraulic chambers 14 of No. 7 and 7 to fix the gear ratio by sealing in the pressure oil in the hydraulic chambers 14.

The gear ratio control valve 48 includes a spool 48a and a spring 4 compressed in a spring chamber 48b at one end of the spool 48a.
8c, and a hydraulic chamber 48d formed at the other end of the spool 48a, to which hydraulic pressure regulated by a gear ratio control solenoid 50 is applied as a pilot pressure, and the spring 48c
Due to the force relationship between the biasing force and the pilot pressure, the spool 4
8a moves left and right to open the hydraulic chamber 1- of the primary pulley 7.
The supply and discharge of pressure oil to and from 4 can be switched. .

Further, the gear ratio fixing valve 49 is integrally molded with the gear ratio control valve 48, and similarly to the gear ratio control valve 48, the gear ratio fixing valve 49 has a spool 49a and a spool 49a.
Spring chamber 49b1 at one end of 9a. :Reduced spring 49C
and a hydraulic chamber 49 formed at the other end of the spool 48a and to which pilot pressure from the gear ratio control solenoid 50 is applied.
d. The four gear ratio fixing valves have a spring 49C whose urging force is set larger than that of the gear ratio control valve 48, and the gear ratio control solenoid 50.
When the pilot pressure from the spring 49c is greater than the biasing force of the spring 49c, the spool 49a moves to the left from the position where the gear ratio control valve 48 and the hydraulic chamber 14 of the primary pulley 7 communicate with each other, as shown in the figure, and moves into the hydraulic chamber 14. It is designed to switch to a position that confines the pressure oil.

Furthermore, 51 is a reducing valve that controls the pressure oil in the oil passage 52 to a constant pressure, which is connected to the secondary pressure solenoid 33, the clutch pressure solenoid 36, the gear ratio control solenoid 50, and the lock-up control solenoid 55, which will be described later. Reference numeral 53 denotes a lock-up switching valve connected to the clutch pressure valve 34 via an oil passage 54, and the lock-up switching valve 53 includes a spool 53a and a spring 5 compressed in a spring chamber 53b at one end of the spool 53a.
3C, and a hydraulic chamber 53d which is formed at the other end of the spool 53a and communicates with an oil passage 52 in which the pressure oil is controlled to a constant pressure by the reducing valve 51. The spring chamber 53b of the lock-up switching valve 53 is connected to a lock-up control solenoid 55, and the lock-up control solenoid 55 applies a predetermined hydraulic pressure as a pilot pressure to the spring chamber 53b, and also applies the pilot pressure to zero. It can be switched depending on the situation.

Further, the lock-up switching valve 53 is supplied with pressure oil in the oil passage 35 whose pressure is regulated by the clutch pressure valve 34 via an oil passage 56, and a lock-up pressure valve 57 is supplied to the oil passage 56. Intervention is provided. The lock-up pressure valve 57 has a spool 57a and a spool 5
a spring 57c compressed into a spring chamber 57b at one end of 7a;
It has a hydraulic chamber 57d to which pilot pressure from the lock-up control solenoid 55 is applied. and,
Both the lock-up switching valve 53 and the lock-up pressure valve 57 are switched depending on whether pilot pressure from the lock-up control solenoid 55 is applied to the spring chamber 53b or the hydraulic chamber 57d. That is, when the pilot pressure is applied, the lock-up switching valve 53 changes its spool 5.
3a moves to a position closer to the right side as indicated in the lower half of the figure by the biasing force of the spring 53c and the pilot pressure of the spring chamber 53b, and the oil passage 58 whose one end is connected to the oil passage 54 and the fluid coupling 1
are in communication with each other, and pressure oil from the clutch pressure valve 34 is supplied to the fluid coupling 1 as its internal pressure oil. Further, the lock-up pressure valve 57 has a spool 57a that is connected to the hydraulic chamber 5.
The pilot pressure of 7d moves it to a position closer to the right side shown in the lower half of the figure, and interrupts communication with the oil passage 56. On the other hand, when no pilot pressure is applied, the lock-up switching valve 53 moves its spool 53a to a position closer to the left side shown in the upper half of the figure by the hydraulic pressure in the hydraulic chamber 53d.
The oil passage 56 and an oil passage 59 connected at one end to the lock-up clutch 6 communicate with each other to supply pressure oil to the lock-up clutch 6, and internal pressure oil of the fluid coupling 1 is discharged via the oil passage 58. As a result, lock-up is achieved, and the oil passage 54 and the oil passage 61, one end of which is connected to the cooler hydraulic circuit 60, communicate with each other, and pressure oil from the clutch pressure valve 34 is supplied to the cooler hydraulic circuit 60. Further, in the lock-up pressure valve 57, the spool 57a moves to a position closer to the left side shown in the upper half of the figure due to the biasing force of the spring 57c, and as the spool 57a moves, the oil passage 56 is gradually opened from the blocked state. As a result, the above-mentioned lock-up is made gradual, and even in the fully connected state, flow resistance is generated, so that the pressure oil supplied to the lock-up clutch 6 is reduced to a constant pressure. Note that the pressure oil in the oil passage 35 whose pressure is regulated by the clutch pressure valve 34 is also used for lubrication 62 of the continuously variable transmission. Further, in FIG. 2, 63 is an oil tank, and 64 is a filter.

The four solenoids, that is, the secondary pressure solenoid 33, the clutch pressure solenoid 36, the gear ratio control solenoid 50, and the lock-up control solenoid 55 are controlled by a controller 70 as a control means having a built-in microcomputer, as shown in FIG. The controller 70 includes a throttle sensor 71 that detects the opening degree of the throttle valve, an engine rotation speed sensor 72 that detects the engine rotation speed (the rotation speed of the engine output shaft 2), and a vehicle speed sensor 73 that detects the vehicle speed. A signal from a position sensor 74 for detecting the shift position of the shift lever is also input.

Next, the details of control by the controller 70 will be explained based on the flowcharts shown in FIGS. 4 and 5.

FIG. 4 shows the main routine processed by the controller 70. This main routine first performs initial settings such as setting the flag α to "0" in step S+, and then in step S2, the clutch pressure by the clutch pressure solenoid 3G (oil line 3 supplied to the hydraulic clutch 21
In step S4, the gear ratio control is performed by the gear ratio control solenoid 50, and in step S4, the secondary pressure is controlled by the secondary pressure solenoid 33.
The discharge pressure of the oil pump 30 supplied to the secondary pulley 9 is controlled by sequentially and repeatedly performing lock-up control using the lock-up control solenoid 55 in step S5.

Further, FIG. 5 shows a subroutine for clutch pressure control. This subroutine first begins with the first step S2.
1, it is determined whether the shift lever is in the R range.

If this determination is YES indicating the R range, the process moves to step S22 and it is determined whether the flag α is "0". If the flag α is "0", the process moves to step S823. In this step S23, it is determined whether the vehicle speed is equal to or higher than a predetermined speed β (for example, 8 km/h), and if YES that the vehicle speed is equal to or higher than the predetermined speed β, the process proceeds to step S21.
Shift to + and reduce the clutch pressure to almost zero.

On the other hand, if it is determined in step S21 that the shift lever is not in the R range, the flag α is set to rOJ in step 825, and then the process proceeds to step S3, in which the clutch pressure is transmitted to the continuously variable transmission. control according to the transmitted torque. Further, in step S22, the flag α is set to “0”.
”, that is, when the flag α is “1”, the process immediately moves to step 82G. If the vehicle speed is not equal to or higher than the predetermined speed β in step 823, step S
After setting the flag α to “1” in step 27, step S
28, the clutch pressure is controlled according to the transmitted torque. Note that the purpose of determining whether the flag α is "0" in step S22 is to check the time elapsed since the R range was selected; if the flag α is "0", the R range is Comment immediately after selecting the range.

Therefore, in the above embodiment, if the shift lever is mistakenly selected to switch to the reverse range (R range) while the vehicle is traveling forward, the controller 70 lowers the clutch pressure according to the clutch pressure control subroutine shown in FIG. When looking at the hydraulic circuit of the hydraulic control device, this control means that the pilot pressure generated in the clutch pressure solenoid 36 becomes zero under the control of the controller 7o, and the clutch pressure valve 34 By reaching the fully open state shown in the upper half of the figure, the oil pressure in the oil passage 35 regulated by the clutch pressure valve 34 becomes almost zero.

Then, when the clutch pressure, that is, the oil pressure in the oil passage 35 becomes almost zero, the hydraulic clutch 21, which is operated by the oil pressure in the oil passage 35, becomes in a state as if its operating pressure oil has been discharged, and the engine torque decreases. Forward/backward switching mechanism 20
Switches to the disconnection position, which cuts off transmission to. Also, the forward and backward mechanism 20.

In the shift actuator 42, even if the oil passage 38 and the oil passage 41 are communicated with each other by the manual valve 39, pressure oil is not supplied to the hydraulic chamber 42d, so that the shift actuator 42 remains in the D range and the switching operation is stopped. For this reason, in a continuously variable transmission, torque transmission is not switched to the reverse direction when the shift lever selects the reverse range, which prevents damage caused by forced forward/reverse switching and improves safety. can be achieved.

Moreover, the clutch pressure valve 34 is originally for regulating the hydraulic pressure (clutch pressure) supplied to the hydraulic clutch 21, and like the conventional reverse inhibitor valve, it is stepless when selecting the reverse range during forward driving. There is no need for a special valve to prevent torque transmission in the transmission from switching to the reverse direction, and the hydraulic control device can be simplified.

In the above embodiment, the clutch pressure is controlled to be reduced to almost zero by the controller 70 when the reverse range is selected during forward running. However, in this control, the clutch pressure is not necessarily reduced to zero. There's no need. This is because the hydraulic clutch 21 is normally switched to the disconnected state even if its working oil pressure does not become completely zero, and the shift actuator 42 of the forward/reverse switching mechanism 20 is switched in the forward range direction by the spring 42e. This is because they are biased to change.

(Effects of the Invention) As described above, according to the control device for the continuously variable transmission of the present invention, when the reverse range is incorrectly selected during forward travel, the hydraulic pressure regulated by the pressure regulating valve decreases.
Since the hydraulic clutch is disengaged and the shift actuator of the forward/reverse switching mechanism is stopped, it is possible to reliably prevent torque transmission from being switched to the reverse direction with the continuously variable speed probe, thereby preventing damage. It is also possible to improve safety. Furthermore, since the configuration is simple and does not require any special valves, the control device can be made smaller and less expensive, which is very advantageous in terms of implementation.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a schematic diagram of the overall configuration of a continuously variable transmission, FIG. 2 is a hydraulic circuit diagram of a hydraulic control I device, and FIG. 3 is a control wiring diagram of a controller. Fig. 4 is a flowchart showing a main routine processed by the controller, and Fig. 5 is a flowchart showing a subroutine for clutch pressure control. 20...Forward/reverse switching mechanism, 21...Hydraulic clutch , 34...Clutch pressure valve, 42...Shift actuator. Fig. 1 Fig. 4 Fig. 5

Claims (1)

[Claims] (1) In a continuously variable transmission equipped with a forward/reverse switching mechanism on a torque transmission system in which engine torque is transmitted via a hydraulic clutch, the shift actuator of the forward/reverse switching mechanism is a pressure regulating valve for the hydraulic clutch. The continuously variable transmission is configured to operate with hydraulic pressure regulated by the above, and the pressure regulating valve is configured to reduce the hydraulic pressure when selecting a reverse range during forward running. Control device.