JP2010065759A - Belt-type continuously variable transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a belt-type continuously variable transmission for improving driveability. <P>SOLUTION: The belt-type continuously variable transmission includes an operating oil supply/drain valve 110 openable in the direction of draining operating oil from a clamping force generating hydraulic pressure chamber 54, an actuator 120 for moving a piston 122 with the hydraulic pressure of the operating oil in a driving hydraulic pressure chamber 124 to close the operating oil supply/drain valve 110 in the direction of supplying the operation oil to the clamping force generating hydraulic pressure chamber 54, and a hydraulic control means 130 for controlling supply hydraulic pressure as the hydraulic pressure of the operating oil to be supplied to the clamping force generating hydraulic pressure chamber 54 and driving hydraulic pressure as the hydraulic pressure of the operating oil in the driving hydraulic pressure chamber 124. The hydraulic control means 130 increases the driving hydraulic pressure when the speed of a vehicle is a preset speed or lower, so that the actuator 120 closes the operating oil supply/drain valve 110. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a belt type continuously variable transmission.

  In general, a vehicle has a transmission on the output side of the drive source in order to transmit a driving force from an internal combustion engine or an electric motor that is a drive source, that is, an output torque, to the road surface under an optimal condition according to the traveling state of the vehicle. Is provided. There are two types of transmissions: a continuously variable transmission that controls the gear ratio steplessly (continuously) and a stepped transmission that controls the gear ratio stepwise (discontinuously). Here, the continuously variable transmission has two pulleys, a primary pulley to which the driving force from the driving source is transmitted, a secondary pulley that changes the output torque transmitted to the primary pulley, and a transmission to the primary pulley. There is a belt-type continuously variable transmission that includes a belt that transmits the generated driving force to a secondary pulley. The primary pulley and the secondary pulley are two pulley shafts arranged in parallel, a primary shaft and a secondary shaft, and two movable sheaves that slide in the axial direction on each shaft (primary movable sheave and secondary movable sheave). Two fixed sheaves (primary fixed sheave and secondary fixed sheave) that face the two movable sheaves in the axial direction and form a V-shaped groove between the movable sheave and the belt clamping pressure against the belt And a clamping pressure generating hydraulic chamber. The belt is wound around a V-shaped groove formed in each of the primary pulley and the secondary pulley.

  In the belt type continuously variable transmission, each movable sheave slides in the axial direction on each shaft by each clamping pressure generating hydraulic chamber, and the width of the V-shaped groove formed in each of the primary pulley and the secondary pulley. To change. As a result, the contact radius between the belt and the primary pulley and the secondary pulley is changed steplessly, and the speed ratio, which is the rotation speed ratio between the primary pulley and the secondary pulley, is changed steplessly. That is, the output torque from the drive source is changed steplessly.

  Such a belt type continuously variable transmission regulates the movement of the movable sheave in the axial direction so that the contact radius of the belt does not change when the transmission gear ratio is fixed. In this case, for example, the belt-type continuously variable transmission described in Patent Document 1 keeps the hydraulic pressure in the clamping pressure generating hydraulic chamber constant so that the movable sheave does not slide in the axial direction. That is, in the belt-type continuously variable transmission described in Patent Document 1, a supply / discharge path for supplying hydraulic oil to the clamping pressure generating hydraulic chamber and discharging hydraulic oil from the clamping pressure generating hydraulic chamber, and a clamping pressure A hydraulic oil supply / discharge valve is provided between the generated hydraulic chamber and the hydraulic oil supply / discharge valve is opened to supply hydraulic oil to the clamping pressure generating hydraulic chamber or to discharge hydraulic fluid from the clamping pressure generating hydraulic chamber. While changing the actual gear ratio, which is the gear ratio, to the target gear ratio, the gear ratio is fixed by closing the hydraulic oil supply / discharge valve.

JP 2006-300270 A

  By the way, in the belt-type continuously variable transmission described in Patent Document 1 as described above, when the speed of a vehicle equipped with the belt-type continuously variable transmission decreases and the rotation speed of the pulley decreases, for example, a pulse The detection accuracy of the primary pulley and the secondary pulley detected by the rotation sensor of the type decreases, and the detection accuracy of the actual gear ratio based on this rotation speed decreases, for example, the accuracy of the gear ratio control decreases. However, drivability may be reduced.

  Therefore, an object of the present invention is to provide a belt type continuously variable transmission that can improve drivability.

  To achieve the above object, a belt-type continuously variable transmission according to the present invention includes two pulleys mounted on a vehicle, a belt wound around each pulley and transmitting a driving force from a driving source, A hydraulic pressure chamber that is formed in each pulley and generates a belt clamping pressure with respect to the belt by hydraulic pressure, and hydraulic oil is supplied to and operated from one clamping pressure generation hydraulic chamber. A supply / discharge path for discharging oil, a hydraulic oil supply / discharge valve provided in the supply / discharge path and capable of opening in a direction to discharge the hydraulic oil from the one clamping pressure generating hydraulic chamber, and a hydraulic oil in the drive hydraulic chamber By shifting the piston by hydraulic pressure, the hydraulic oil supply / discharge valve can be closed in the direction in which the hydraulic oil is supplied to the one clamping pressure generating hydraulic chamber, and a shift that is a rotation speed ratio of the two pulleys. ratio A controllable transmission ratio detection means, a supply hydraulic pressure that is a hydraulic pressure of the hydraulic oil supplied to the one clamping pressure generation hydraulic chamber, and a drive hydraulic pressure that is a hydraulic pressure of the hydraulic oil in the drive hydraulic chamber; By reducing the drive oil pressure, the hydraulic oil supply / discharge valve is opened to supply hydraulic oil to the one clamping pressure generating hydraulic chamber, or the hydraulic oil is discharged from the one clamping pressure generating hydraulic chamber to change the gear ratio. A hydraulic control unit configured to change the transmission gear ratio detected by the detection unit to a target transmission gear ratio, and to increase the driving hydraulic pressure to close the hydraulic oil supply / discharge valve and fix the transmission gear ratio by the actuator; And the hydraulic control means closes the hydraulic oil supply / discharge valve by the actuator by increasing the drive hydraulic pressure when the speed of the vehicle falls below a predetermined speed set in advance. And wherein the door.

  According to the belt-type continuously variable transmission according to the present invention, when the vehicle speed becomes equal to or lower than a predetermined speed set in advance, the gear ratio can be fixed and drivability can be improved.

  Hereinafter, the present invention will be described in detail with reference to the drawings. In addition, this invention is not limited by the following embodiment. In addition, constituent elements in the following embodiments include those that can be easily assumed by those skilled in the art or that are substantially the same. Here, an internal combustion engine (a gasoline engine, a diesel engine, an LPG engine, or the like) is used as a drive source for generating a drive force transmitted to the belt type continuously variable transmission in the following embodiment, but the invention is not limited to this. Alternatively, an electric motor such as a motor may be used as a drive source. In the following embodiment, one pulley is a primary pulley and the other pulley is a secondary pulley. However, one pulley may be a secondary pulley and the other pulley may be a primary pulley.

(Embodiment 1)
1 is a schematic configuration diagram of a vehicle equipped with a belt-type continuously variable transmission according to Embodiment 1 of the present invention, and FIGS. 2-1 and 2-2 are belt-type continuously variable according to Embodiment 1 of the present invention. FIG. 3 is a conceptual diagram schematically showing the schematic configuration of the hydraulic control device for the belt-type continuously variable transmission according to the first embodiment of the present invention.

  As shown in FIG. 1, the power transmission mechanism of the vehicle 10 includes an internal combustion engine 12, a torque converter 16, a forward / reverse switching mechanism 20, a belt-type continuously variable transmission 22, a speed reducer 24, and a differential device 28. With.

  In the internal combustion engine 12, a piston reciprocates in the central axis direction of a cylinder formed in a cylindrical shape, and outputs rotation from a crankshaft 14 that converts the reciprocating motion of the piston into a rotational motion. The internal combustion engine 12 is not limited to a so-called reciprocating internal combustion engine including a piston and a cylinder. The internal combustion engine 12 may be any engine that can output rotational force, and may be, for example, a rotary internal combustion engine.

  The torque converter 16 is a kind of fluid clutch, and transmits the rotation extracted from the internal combustion engine 12 to the forward / reverse switching mechanism 20 by hydraulic oil. The torque converter 16 amplifies the torque extracted from the internal combustion engine 12.

  The forward / reverse switching mechanism 20 is a mechanism for transmitting the rotation taken out from the torque converter 16 to the belt-type continuously variable transmission 22 and switches the direction of the rotation taken out from the torque converter 16 as necessary to change the belt-type continuously variable transmission. To the machine 22.

  The belt type continuously variable transmission 22 changes the rotation speed (rotation speed) input from the forward / reverse switching mechanism 20 to a desired rotation speed (rotation speed) and outputs the change. The detailed description of the belt type continuously variable transmission 22 will be described later.

  The speed reduction device 24 reduces the rotational speed of the rotation from the belt type continuously variable transmission 22 and transmits the rotation to the differential device 28.

  The differential device 28 absorbs the difference in rotational speed between the center driving wheel 34, that is, the inner driving wheel 34 and the outer driving wheel 34, which occurs when the vehicle 10 turns.

  A power transmission mechanism of the vehicle 10 is formed by the above components. That is, the rotation extracted from the internal combustion engine 12 is transmitted to the torque converter 16 via the crankshaft 14. The rotation whose torque has been amplified by the torque converter 16 is transmitted to the forward / reverse switching mechanism 20 via the input shaft 18 of the torque converter 16.

  The rotation whose rotation direction is switched by the forward / reverse switching mechanism 20 is transmitted to the belt-type continuously variable transmission 22 via a primary shaft 51 as an input-side shaft. The rotation whose rotation speed has been changed by the belt-type continuously variable transmission 22 is transmitted to the speed reduction device 24.

  The rotation decelerated by the reduction device 24 is transmitted to the differential device 28 via the final drive pinion 26 of the reduction device 24 and the ring gear 30 of the differential device 28 that meshes with the final drive pinion 26.

  The rotation transmitted to the differential device 28 is transmitted to the drive shaft 32. A drive wheel 34 is attached to the side of the drive shaft 32 opposite to the differential device 28 side. The rotation transmitted to the drive shaft 32 is transmitted to the drive wheel 34. As a result, the driving wheel 34 rotates, and the vehicle 10 travels when the driving wheel 34 transmits the rotation to the road surface.

  The belt-type continuously variable transmission 22 includes two pulleys, that is, a primary pulley 50 as one pulley, a secondary pulley 60 as the other pulley, and a belt 80. The belt type continuously variable transmission 22 further includes a switching mechanism 100 (see FIG. 2-1) and a hydraulic control device 130 (see FIG. 3) as hydraulic control means.

  The belt-type continuously variable transmission 22 receives rotation input to the primary pulley 50. The rotation input to the primary pulley 50 is transmitted to the secondary pulley 60 via the belt 80. At this time, the rotation speed (number of rotations) of the rotation is adjusted.

  The rotation transmitted to the secondary pulley 60 is transmitted to the speed reducer 24. A value obtained by dividing the rotational speed of the primary shaft 51 as the input shaft by the rotational speed of the secondary shaft 61 as the output shaft is referred to as a gear ratio. That is, the gear ratio corresponds to the rotation speed ratio between the primary shaft 51 and the secondary shaft 61.

  The primary pulley 50 includes a primary shaft 51, a primary fixed sheave 52, a primary movable sheave 53, and a primary hydraulic chamber 54 as a clamping pressure generating hydraulic chamber. On the other hand, the secondary pulley 60 includes a secondary shaft 61, a secondary fixed sheave 62, a secondary movable sheave 63, and a secondary hydraulic chamber 64 as a clamping pressure generating hydraulic chamber. The primary shaft 51 is supported by a bearing 81 and a bearing 82 so as to be rotatable coaxially with the rotation shaft of the input shaft 18. The secondary shaft 61 is supported by a bearing 83 and a bearing 84 so as to be rotatable in parallel with the primary shaft 51.

  In the belt type continuously variable transmission 22, the primary pulley 50 and the secondary pulley 60 are configured in substantially the same manner. Therefore, in this embodiment, the primary pulley 50 will be mainly described, and the description of the secondary pulley 60 will be omitted as much as possible.

  As shown in FIGS. 2A and 2B, the primary pulley 50 includes a spline 55 and a primary partition wall 56 in addition to the above-described primary shaft 51, primary fixed sheave 52, primary movable sheave 53, and the like. .

  The primary shaft 51 is formed in a cylindrical shape. The primary shaft 51 is supported by a bearing 81 and a bearing 82 so as to be rotatable about the rotation axis RL as a rotation center.

  The primary fixed sheave 52 is usually formed integrally with the primary shaft 51. Accordingly, the primary fixed sheave 52 rotates integrally with the primary shaft 51 around the rotation axis RL. Here, a direction orthogonal to the rotation axis RL is referred to as a radial direction. The primary fixed sheave 52 is formed to protrude radially outward from the outer periphery of the primary shaft 51. The primary fixed sheave 52 may be formed separately from the primary shaft 51 and fixed to the primary shaft 51.

  Primary movable sheave 53 is formed separately from primary shaft 51. The primary movable sheave 53 has a through hole into which the primary shaft 51 is fitted. A spline 55 is formed on the inner peripheral surface of the through hole. Primary movable sheave 53 is fitted and attached to primary shaft 51 via spline 55. The primary movable sheave 53 is fitted into the primary shaft 51 so as to face the primary fixed sheave 52 in the direction along the rotation axis RL, that is, in the axial direction.

  The spline 55 supports the primary movable sheave 53 so that the primary movable sheave 53 can slide on the primary shaft 51 along the rotation axis RL. In addition, the spline 55 transmits rotation about the rotation axis RL to the primary movable sheave 53 from the primary shaft 51. Therefore, the primary movable sheave 53 is supported by the primary shaft 51 via the spline 55, so that the primary movable sheave 53 can move in the axial direction on the primary shaft 51 and rotate integrally with the primary shaft 51.

  A substantially V-shaped primary groove 80 a is formed between the primary fixed sheave 52 and the primary movable sheave 53. Further, as the primary movable sheave 53 slides on the primary shaft 51, the distance between the primary fixed sheave 52 and the primary movable sheave 53 changes. Here, a secondary groove 80b (see FIG. 1) similar to the primary groove 80a is also formed in the secondary pulley 60 (see FIG. 1).

  A belt 80, which is a metal endless belt, is wound between the primary groove 80a and the secondary groove 80b. The belt 80 transmits the rotation of the primary pulley 50 to the secondary pulley 60.

  The primary hydraulic chamber 54 is a space portion formed by being surrounded by the primary shaft 51, the primary movable sheave 53, and the primary partition wall 56. The primary partition 56 is formed having a through hole. The primary partition wall 56 is provided on the primary shaft 51 by fitting the primary shaft 51 into the through hole. The primary partition wall 56 is provided on the side opposite to the primary fixed sheave 52 side with the primary movable sheave 53 as a boundary.

  The primary hydraulic chamber 54 applies a pressing force toward the primary fixed sheave 52 to the primary movable sheave 53 by the hydraulic oil supplied to the primary hydraulic chamber 54. Thereby, the primary movable sheave 53 is pushed along the primary shaft 51 to the primary fixed sheave 52 side. Therefore, the primary hydraulic chamber 54 can apply a belt clamping pressure to the belt 80 wound around the primary groove 80 a via the primary movable sheave 53.

  When the primary movable sheave 53 is moved by the primary hydraulic chamber 54 and the distance between the primary movable sheave 53 and the primary fixed sheave 52 is changed, the distance between the secondary fixed sheave 62 and the secondary movable sheave 63 provided in the secondary pulley 60 is also the belt 80. It changes to keep the tension constant. Thereby, the contact radius of the belt 80 with respect to the primary pulley 50 and the contact radius of the belt 80 with respect to the secondary pulley 60 change. In this way, the belt type continuously variable transmission 22 can change the rotation extracted from the internal combustion engine 12.

  Here, the primary shaft 51 has a first oil passage 86. The first oil passage 86 forms part of a supply / discharge path for supplying hydraulic oil to the primary hydraulic chamber 54 and discharging hydraulic oil from the primary hydraulic chamber 54. The first oil passage 86 has one end connected to a switching mechanism 100 described later, and the other end connected to the primary hydraulic chamber 54. As a result, the first oil passage 86 can flow hydraulic oil between the switching mechanism 100 and the primary hydraulic chamber 54. The first oil passage 86 includes an axial oil passage 88 formed in a direction along the rotation axis RL of the primary shaft 51 and a radial oil passage 90 formed in a direction orthogonal to the rotation axis RL. Formed with.

  The switching mechanism 100 is disposed in a hydraulic oil flow path between the primary hydraulic chamber 54 and a hydraulic control device 130 described later, and allows the hydraulic oil to flow between the primary hydraulic chamber 54 and the hydraulic control device 130 described later. And a state where distribution is prohibited. That is, the switching mechanism 100 includes a state in which the primary hydraulic chamber 54 and the hydraulic control device 130 are in communication with each other as shown in FIG. 2-1, and the primary hydraulic chamber 54 and the hydraulic control device 130 in FIG. Is switched off. The switching mechanism 100 includes a second oil passage 102, a hydraulic oil supply / discharge valve 110, and an actuator 120.

  The second oil passage 102 forms part of a supply / discharge path for supplying hydraulic oil to the primary hydraulic chamber 54 and discharging hydraulic oil from the primary hydraulic chamber 54. One end of the second oil passage 102 is connected to the first oil passage 86, and the other end is connected to a primary hydraulic chamber control device 135 of the hydraulic control device 130 described later. Further, the second oil passage 102 and the first oil passage 86 are connected by, for example, a rotary joint so that the second oil passage 102 does not rotate even if the first oil passage 86 rotates.

  The hydraulic oil supply / discharge valve 110 is provided in the second oil passage 102 that forms a part of the supply / discharge passage, and the hydraulic oil is discharged from the primary hydraulic chamber 54 in the second oil passage 102, that is, on the primary hydraulic chamber 54 side. The valve can be opened from the (first oil passage 86 side) toward the hydraulic control device 130 side. The hydraulic oil supply / discharge valve 110 includes a valve seat portion 112 and a valve body 114.

  The valve seat 112 is formed as a tapered surface in the second oil passage 102 such that the flow passage area increases from the primary hydraulic chamber 54 side (first oil passage 86 side) toward the hydraulic control device 130 side. That is, the valve seat portion 112 is continuous with the inner wall surface forming the second oil passage 102, and inclines inward in the radial direction as it goes toward the primary hydraulic chamber 54 side (first oil passage 86 side). Tapered surface.

  The valve body 114 is a spherical member having a diameter larger than the opening inner diameter of the end portion of the valve seat portion 112 on the first oil passage 86 side. The valve body 114 is disposed on the hydraulic control device 130 side of the valve seat portion 112 in the second oil passage 102 and can approach and separate from the valve seat portion 112.

  Therefore, the hydraulic oil supply / discharge valve 110 moves in the direction in which the valve body 114 supplies the hydraulic oil to the primary hydraulic chamber 54 in the second oil passage 102, approaches the valve seat portion 112, and the valve body 114 and the valve seat portion When the valve 112 comes into contact, the valve is closed. The hydraulic oil supply / discharge valve 110 moves in a direction in which the valve body 114 discharges hydraulic oil from the primary hydraulic chamber 54 in the second oil passage 102 and moves away from the valve seat portion 112, so that the valve body 114, the valve seat portion 112, Is in a non-contact state.

  The actuator 120 can forcibly close the hydraulic oil supply / discharge valve 110 in the direction of supplying hydraulic oil to the primary hydraulic chamber 54. The actuator 120 includes a piston 122, a drive hydraulic chamber 124, and a spring 126 as urging means.

  The piston 122 has a pressure receiving part 122a and a rod-like part 122b. The pressure receiving portion 122a is a plate-like member, and is disposed inside a drive hydraulic chamber 124, which will be described later, and receives a pressing force due to the hydraulic pressure of the hydraulic oil in the drive hydraulic chamber 124. One end of the rod-like portion 122b is fixed to the pressure receiving portion 122a, and the other end is fixed to the valve body 114.

  The drive hydraulic chamber 124 is a space section partitioned by a hydraulic chamber wall surface and supplied with hydraulic oil, and the pressure receiving portion 122a of the piston 122 is disposed therein as described above. The drive hydraulic chamber 124 has a shape in which the area of the inner space portion parallel to the surface of the pressure receiving portion 122a is substantially the same as the area of the pressure receiving portion 122a. The drive hydraulic chamber 124 is connected to the drive hydraulic chamber control device 136, and hydraulic oil is supplied and discharged from the drive hydraulic chamber control device 136. When the hydraulic oil is supplied to the inside of the drive hydraulic chamber 124, a pressure is applied to the pressure receiving portion 122a by the hydraulic pressure of the hydraulic oil, and the pressure receiving portion 122a is pushed out to the valve seat portion 112 side. Therefore, when the pressure receiving portion 122a is pushed by the hydraulic pressure of the hydraulic oil in the drive hydraulic chamber 124, the piston 122 moves to the valve seat portion 112 side, and the valve body 114 moves to the valve seat portion 112 side together with the piston 122. .

  The spring 126 is, for example, a coil spring, and a surface to which the rod-shaped portion 122b of the pressure receiving portion 122a is fixed (that is, a surface opposite to the surface on which the hydraulic pressure acts) and a drive hydraulic chamber 124 facing the surface. It is arrange | positioned between the hydraulic chamber wall surfaces. The spring 126 urges the pressure receiving portion 122a toward the side away from the valve seat portion 112.

  In the switching mechanism 100 configured as described above, hydraulic oil is supplied to the drive hydraulic chamber 124, and the pressure receiving portion 122a is pushed out toward the valve seat portion 112 by the hydraulic pressure of the internal hydraulic oil. Here, when the hydraulic pressure of the hydraulic oil inside the drive hydraulic chamber 124 becomes a certain level or more, as shown in FIG. 2B, the pressure receiving portion 122a is moved to the valve seat portion 112 side by a certain distance, and the valve body 114 is moved to the valve seat. The opening of the portion 112 is closed. That is, the hydraulic oil supply / discharge valve 110 moves in the direction in which the valve body 114 supplies the hydraulic oil to the primary hydraulic chamber 54 in the second oil passage 102 and approaches the valve seat portion 112, so that the valve body 114 and the valve seat portion As a result, the valve 112 is closed and the primary hydraulic chamber 54 and the hydraulic control device 130 are disconnected from each other. As a result, the hydraulic oil is confined in the primary hydraulic chamber 54. Basically, the hydraulic oil is supplied into the primary hydraulic chamber 54, or the hydraulic oil is discharged from the primary hydraulic chamber 54. Therefore, the amount of hydraulic oil inside the primary hydraulic chamber 54 does not change.

  On the other hand, when the hydraulic pressure of the hydraulic oil in the drive hydraulic chamber 124 is below a certain level, the pressure receiving portion 122a is pushed away from the valve seat portion 112 by the spring 126 as shown in FIG. There is a space between the valve seat 112 and the opening of the valve seat 112. That is, the hydraulic oil supply / discharge valve 110 moves in a direction in which the valve body 114 discharges the hydraulic oil from the primary hydraulic chamber 54 in the second oil passage 102, moves away from the valve seat portion 112, and is separated from the valve body 114 and the valve seat portion. When the valve 112 is not in contact, the valve is opened, and the primary hydraulic chamber 54 and the hydraulic control device 130 communicate with each other. As a result, the hydraulic oil can be supplied into the primary hydraulic chamber 54 and the hydraulic oil can be discharged from the primary hydraulic chamber 54.

  The hydraulic control device 130 is a hydraulic control unit that supplies hydraulic oil to a hydraulic oil supply portion that requires supply of hydraulic oil in the vehicle 10 on which the belt-type continuously variable transmission 22 and the internal combustion engine 12 are mounted. It is. The hydraulic control device 130 controls the supply and discharge of hydraulic fluid to and from the primary hydraulic chamber 54 that is one clamping pressure generating hydraulic chamber, and supplies and discharges hydraulic fluid to and from the secondary hydraulic chamber 64 that is the other clamping pressure generating hydraulic chamber. Is to control. The hydraulic control device 130 also controls supply hydraulic pressure that is hydraulic pressure of hydraulic oil supplied to each of the primary hydraulic chamber 54 and the secondary hydraulic chamber 64. When the hydraulic oil supply / discharge valve 110 is forcibly opened by the actuator 120, the hydraulic control device 130 supplies hydraulic oil to the primary hydraulic chamber 54, which is one clamping pressure generating hydraulic chamber, or from the primary hydraulic chamber 54. The gear ratio is controlled by discharging hydraulic oil. Further, the hydraulic control device 130 of the present embodiment supplies hydraulic oil to the drive hydraulic chamber 124 and controls the drive hydraulic pressure that is the hydraulic pressure of the hydraulic oil in the drive hydraulic chamber 124.

  As shown in FIG. 3, the hydraulic control device 130 supplies hydraulic oil to the primary hydraulic chamber 54, the secondary hydraulic chamber 64, the drive hydraulic chamber 124, and the like, and supplies the hydraulic pressure, the hydraulic oil supply flow rate, and the hydraulic oil discharge flow rate. By controlling this, the gear ratio of the belt type continuously variable transmission 22 is also controlled. In the figure, the hydraulic oil supply portion (excluding the hydraulic oil supply portion described above and the hydraulic oil supply portion of the internal combustion engine 12 (for example, movable parts) is excluded from the primary hydraulic chamber 54, the secondary hydraulic chamber 64, and the drive hydraulic chamber 124. The illustration of a stationary part having a sliding part in between, a movable part or a movable part having a sliding part between stationary parts, a heated part or a driving device driven by oil) is omitted. The hydraulic control device 130 includes an oil pan 131, an oil pump 132, a line pressure control device 133, a constant pressure control device 134, a primary hydraulic chamber control device 135, a drive hydraulic chamber control device 136, and a secondary hydraulic pressure. And a room control device 137.

  The oil pump 132 sucks, pressurizes, and discharges the hydraulic oil stored in the oil pan 131. The oil pump 132 is connected to the line pressure control device 133 via the oil passage R1. The hydraulic oil pressurized and discharged by the oil pump 132 is supplied to the line pressure control device 133. That is, the discharge pressure of the oil pump 132 is introduced into the line pressure control device 133. As shown in FIG. 1, the oil pump 132 is disposed between the torque converter 16 and the forward / reverse switching mechanism 20. The oil pump 132 includes a rotor 132a, a hub 132b, and a body 132c. The oil pump 132 is connected to the pump of the torque converter 16 via a rotor 132a and a cylindrical hub 132b. The body 132c is fixed to a casing that supports the belt type continuously variable transmission 22 and the like. The hub 132b is spline-fitted to the hollow shaft of the torque converter 16. Therefore, the oil pump 132 can be driven because the output torque from the internal combustion engine 12 is transmitted to the rotor 132a via the pump of the torque converter 16. That is, the oil pump 132 increases the amount of discharged hydraulic oil, that is, increases the discharge pressure, as the rotational speed of the internal combustion engine 12 increases.

  The line pressure control device 133 adjusts the pressure of the hydraulic oil supplied as the discharge pressure from the oil pump 132 so as to become a predetermined line pressure PL. That is, the line pressure control device 133 adjusts the hydraulic pressure of the oil passage R1, which is the input hydraulic pressure, that is, the discharge pressure, and sets the output hydraulic pressure from the line pressure control device 133 as the line pressure PL. The line pressure control device 133 is connected to a second port 135l of a supply-side flow rate control valve 135c, which will be described later, of the primary hydraulic chamber control device 135 via an oil passage R2, and is constant via an oil passage R2 and a branch oil passage R21. It is connected to the pressure control device 134 and is connected to the secondary hydraulic chamber control device 137 via the oil passage R2 and the branch oil passage R22. Therefore, the line pressure PL adjusted by the line pressure control device 133 is introduced into the second port 135l of the supply side flow rate control valve 135c, the constant pressure control device 134, and the secondary hydraulic chamber control device 137.

  The line pressure control device 133 adjusts the line pressure PL according to the output torque of the internal combustion engine 12. The line pressure control device 133 is provided with a solenoid valve (not shown), for example, a linear solenoid valve, which regulates the pressure of the hydraulic oil discharged from the oil pump 132. The line pressure control device 133 is electrically connected to the ECU 140, and the line pressure PL can be regulated by controlling the valve opening degree of the linear solenoid valve by a control signal from the ECU 140.

  The constant pressure control device 134 adjusts the line pressure PL output from the line pressure control device 133 so as to always become a constant pressure. That is, the constant pressure control device 134 adjusts the oil pressure of the oil passage R2 and the branch oil passage R21 that are input oil pressure, that is, the line pressure PL, and sets the output oil pressure from the constant pressure control device 134 to the constant pressure PS. is there. The constant pressure control device 134 is connected to a first port 135e of a supply side control valve 135a, which will be described later, of the primary hydraulic chamber control device 135 via an oil passage R3, and is connected to the primary hydraulic pressure via an oil passage R3 and a branch oil passage R31. It connects with the 1st port 135h of the discharge side control valve 135b mentioned later of the chamber control apparatus 135, and is connected with the drive hydraulic chamber control apparatus 136 via the oil path R3 and the branch oil path R32. Accordingly, the constant pressure PS regulated by the constant pressure control device 134 is introduced into the first port 135e of the supply side control valve 135a, the first port 135h of the discharge side control valve 135b, and the drive hydraulic chamber control device 136. .

  The primary hydraulic chamber controller 135 controls the supply of hydraulic oil to the primary hydraulic chamber 54 or the discharge of hydraulic oil from the primary hydraulic chamber 54. In the first embodiment, the primary hydraulic chamber control device 135 controls the supply flow rate of the hydraulic oil supplied to the primary hydraulic chamber 54 and the discharge flow rate of the hydraulic oil discharged from the primary hydraulic chamber 54. The primary hydraulic chamber control device 135 includes a supply-side control valve 135a, a discharge-side control valve 135b, a supply-side flow rate control valve 135c, and a discharge-side flow rate control valve 135d.

  The supply side control valve 135a controls the supply flow rate of the hydraulic oil supplied to the primary hydraulic chamber 54 by the supply side flow rate control valve 135c. The supply-side control valve 135a switches communication between the three ports, that is, the first port 135e, the second port 135f, and the third port 135g by ON / OFF. The first port 135e is connected to the constant pressure control device 134 as described above. The second port 135f is connected to a first port 135k, which will be described later, of the supply-side flow rate control valve 135c via an oil passage R4. The second port 135f is connected to a later-described fourth port 135u of the discharge-side flow rate control valve 135d via the oil passage R4 and the branch oil passage R41. The third port 135g is connected to the oil pan 131 via the merging oil passage R51 and the oil passage R5. That is, the third port 135g is released to atmospheric pressure.

  When the supply-side control valve 135a is turned on, the first port 135e and the second port 135f communicate with each other. Therefore, the constant pressure PS introduced into the supply side control valve 135a is introduced into the first port 135k of the supply side flow control valve 135c. That is, the constant pressure PS introduced into the supply side control valve 135a is introduced into a control hydraulic chamber 135o, which will be described later, of the supply side flow control valve 135c communicating with the first port 135k. Further, the constant pressure PS introduced into the supply side control valve 135a is introduced into the fourth port 135u of the discharge side flow control valve 135d. On the other hand, when the supply-side control valve 135a is turned off, the second port 135f and the third port 135g communicate with each other. Accordingly, the first port 135k of the supply side flow control valve 135c is released to the atmospheric pressure via the supply side control valve 135a. That is, the control hydraulic pressure chamber 135o is released to atmospheric pressure via the first port 135k of the supply side flow control valve 135c. Further, the fourth port 135u of the discharge side flow control valve 135d is released to atmospheric pressure through the supply side control valve 135a. Here, the supply-side control valve 135a is electrically connected to the ECU 140 and is duty-controlled by a control signal from the ECU 140. Therefore, the supply-side control valve 135a can regulate the control hydraulic chamber 135o of the supply-side flow rate control valve 135c from a constant pressure PS to atmospheric pressure by a control signal from the ECU 140.

  The discharge side control valve 135b performs discharge flow control of the hydraulic oil discharged from the primary hydraulic chamber 54 by the discharge side flow control valve 135d. The discharge side control valve 135b switches communication between the three ports, that is, the first port 135h, the second port 135i, and the third port 135j by ON / OFF. The first port 135h is connected to the constant pressure control device 134 as described above. The second port 135i is connected to a later-described first port 135r of the discharge-side flow rate control valve 135d via the oil path R6. The second port 135i is connected to a later-described fourth port 135n of the supply-side flow rate control valve 135c through the oil passage R6 and the branch oil passage R61. The third port 135j is connected to the oil pan 131 via the oil path R5. That is, the third port 135j is released to atmospheric pressure.

  When the discharge-side control valve 135b is turned on, the first port 135h and the second port 135i communicate with each other. Therefore, the constant pressure PS introduced into the discharge side control valve 135b is introduced into the first port 135r of the discharge side flow control valve 135d. That is, the constant pressure PS introduced into the discharge side control valve 135b is introduced into a later-described control hydraulic chamber 135v of the discharge side flow control valve 135d communicating with the first port 135r. In addition, the constant pressure PS introduced into the discharge side control valve 135b is introduced into the fourth port 135n of the supply side flow control valve 135c. On the other hand, when the discharge side control valve 135b is turned off, the second port 135i and the third port 135j communicate with each other. Therefore, the first port 135r of the discharge side flow control valve 135d is released to atmospheric pressure via the discharge side control valve 135b. That is, the control hydraulic chamber 135v is released to the atmospheric pressure via the first port 135r of the discharge side flow control valve 135d. Further, the fourth port 135n of the supply side flow control valve 135c is released to atmospheric pressure via the discharge side control valve 135b. Here, the discharge side control valve 135b is electrically connected to the ECU 140, and is duty-controlled by a control signal from the ECU 140. Therefore, the discharge-side control valve 135b can regulate the control hydraulic chamber 135v of the discharge-side flow control valve 135d from a constant pressure PS to atmospheric pressure by a control signal from the ECU 140.

  The supply-side flow rate control valve 135c controls the supply flow rate of the hydraulic oil supplied to the primary hydraulic chamber 54. The supply-side flow rate control valve 135c includes a first port 135k, a second port 135l, a third port 135m, a fourth port 135n, a control hydraulic chamber 135o, a spool 135p, and a spool elastic member 135q. ing. As described above, the first port 135k is connected to the second port 135f of the supply side control valve 135a. The second port 135l is connected to the line pressure control device 133 as described above. The third port 135m is connected to the primary hydraulic chamber 54 via an oil passage R7. In the first embodiment, the third port 135m is connected to the primary hydraulic chamber 54 via the oil path R7, the second oil path 102 and the first oil path 86 as supply and discharge paths. The fourth port 135n is connected to the second port 135i of the discharge side control valve 135b as described above. As shown in FIG. 3, between the second port 135f of the supply-side control valve 135a and the first port 135k of the supply-side flow control valve 135c, the line pressure controller 133 and the second of the supply-side flow control valve 135c An orifice, that is, a throttle is provided between the port 135l and the hydraulic oil flowing from the supply-side control valve 135a to the supply-side flow control valve 135c and the hydraulic oil flowing from the line pressure control device 133 to the supply-side flow control valve 135c. The pressure or flow rate may be adjusted.

  The control hydraulic chamber 135o communicates with the first port 135k, and the spool valve opening direction pressing force that presses the spool 135p in one direction (upward in FIG. 3) in the direction in which the spool 135p moves due to the hydraulic pressure. Is made to act on the spool 135p. The spool 135p is movably supported in the supply-side flow rate control valve 135c, and moves in one direction among the moving directions so as to communicate the second port 135l and the third port 135m. By moving in the direction, the communication between the second port 135l and the third port 135m is blocked. The spool elastic member 135q is disposed in a state of being biased between the spool 135p and a member stationary with respect to the spool 135p. Therefore, the spool elastic member 135q generates a spool urging force, and the spool urging force pushes the spool 135p in the other direction (downward in FIG. 3) in the direction in which the spool 135p moves. The pressure is applied to the spool 135p.

  In the supply-side flow rate control valve 135c, the spool valve opening direction pressing force acting on the spool 135p exceeds the spool valve closing direction pressing force, whereby the spool 135p moves in one of the moving directions. Here, the supply-side flow rate control valve 135c has a degree of communication between the second port 135l and the third port 135m, that is, with respect to the second port 135l as the movement amount in one direction of the movement direction of the spool 135p increases. The channel cross-sectional area of the channel that communicates with the third port 135m increases. That is, the supply-side flow rate control valve 135c has two ports, that is, a second port 135l and a third port 135m, as the spool 135p moves by the hydraulic pressure of the control hydraulic chamber 135o regulated by the supply-side control valve 135a. And the supply flow rate is controlled.

  The discharge-side flow rate control valve 135d controls the discharge flow rate of the hydraulic oil discharged from the primary hydraulic chamber 54. The discharge-side flow rate control valve 135d includes a first port 135r, a second port 135s, a third port 135t, a fourth port 135u, a control hydraulic chamber 135v, a spool 135w, and a spool elastic member 135x. ing. The first port 135r is connected to the second port 135i of the discharge side control valve 135b as described above. The second port 135s is connected to the oil pan 131 via the merging oil path R52, the merging oil path R51, and the oil path R5. That is, the second port 135s is released to atmospheric pressure. The third port 135t is connected to the primary hydraulic chamber 54 via the branch oil passage R71 and the oil passage R7. In the first embodiment, the third port 135t is connected to the primary hydraulic chamber 54 via the branch oil passage R71, the oil passage R7, the second oil passage 102 as the supply / discharge passage, and the first oil passage 86. As described above, the fourth port 135u is connected to the second port 135f of the supply side control valve 135a. As shown in FIG. 3, an orifice, that is, a throttle is provided between the second port 135i of the discharge-side control valve 135b and the first port 135r of the discharge-side flow control valve 135d to discharge from the discharge-side control valve 135b. The pressure or flow rate of the hydraulic oil flowing into the side flow rate control valve 135d may be adjusted.

  The control hydraulic chamber 135v communicates with the first port 135r, and the spool valve opening direction pressing force that presses the spool 135w in one direction (upward in FIG. 3) in the direction in which the spool 135w moves due to the hydraulic pressure. Is applied to the spool 135w. The spool 135w is movably supported in the discharge-side flow rate control valve 135d, and moves in one direction among the moving directions so as to communicate the second port 135s and the third port 135t. By moving in the direction, the communication between the second port 135s and the third port 135t is blocked. The spool elastic member 135x is disposed in a state of being biased between the spool 135w and a member stationary with respect to the spool 135w. Therefore, the spool elastic member 135x generates a spool urging force, and the spool urging force pushes the spool 135w in the other direction (downward in FIG. 3) in the direction in which the spool 135w moves. The pressure is applied to the spool 135w.

  The discharge-side flow rate control valve 135d moves the spool 135w in one of the moving directions when the spool valve opening direction pressing force acting on the spool 135w exceeds the spool closing direction pressing force. Here, the discharge-side flow rate control valve 135d increases the degree of communication between the second port 135s and the third port 135t, that is, the second port 135s with the increase in the movement amount in one direction of the movement direction of the spool 135w. The channel cross-sectional area of the channel communicating with the third port 135t increases. In other words, the discharge-side flow rate control valve 135d has two ports, that is, the second port 135s and the third port 135t, as the spool 135w moves by the hydraulic pressure of the control hydraulic chamber 135v regulated by the discharge-side control valve 135b. And the discharge flow rate is controlled.

  The drive hydraulic chamber controller 136 regulates the drive hydraulic pressure that is the hydraulic pressure of the drive hydraulic chamber 124. As described above, the constant pressure PS is introduced from the constant pressure control device 134 into the drive hydraulic chamber control device 136. Further, the drive hydraulic chamber control device 136 is connected to the drive hydraulic chamber 124 via an oil passage R8. The drive hydraulic chamber control device 136 includes a duty solenoid valve (not shown). The drive hydraulic chamber control device 136 is electrically connected to the ECU 140 and controls ON / OFF of the duty solenoid valve by a control signal from the ECU 140. When the drive hydraulic chamber control device 136 is ON-controlled, that is, when the duty solenoid valve is turned ON, the branch oil passage R32 and the oil passage R8 communicate with each other, and the constant is introduced into the drive hydraulic chamber control device 136. The pressure PS is introduced into the drive hydraulic chamber 124, and the hydraulic pressure in the drive hydraulic chamber 124 becomes the constant pressure PS. On the other hand, when the drive hydraulic chamber control device 136 is controlled to be OFF, that is, when the duty solenoid valve is turned OFF, the communication between the branch oil path R32 and the oil path R8 is cut off, and the oil path R8 is externally connected. The hydraulic pressure P2 in the drive hydraulic chamber 124 becomes atmospheric pressure.

  The secondary hydraulic chamber control device 137 controls the supply of hydraulic oil to the secondary hydraulic chamber 64 or the discharge of hydraulic oil from the secondary hydraulic chamber 64, and has substantially the same configuration as the primary hydraulic chamber control device 135. is doing. As described above, the line pressure PL is introduced into the secondary hydraulic chamber control device 137 from the line pressure control device 133. The secondary hydraulic chamber control device 137 is connected to the secondary hydraulic chamber 64 via an oil passage R9. In the first embodiment, the secondary hydraulic chamber control device 137 is connected to the secondary hydraulic chamber 64 via an oil passage R9, a hydraulic oil passage (not shown) of the secondary shaft 61, and a hydraulic fluid supply hole (not shown). The secondary hydraulic chamber control device 137 includes a flow rate control valve (not shown). The secondary hydraulic chamber control device 137 is electrically connected to the ECU 140 and regulates the introduced line pressure PL controlled by a control signal from the ECU 140.

  The hydraulic control device 130 is connected to an ECU (Electronic Control Unit) 140 that controls the operation of the internal combustion engine 12 and the like. The ECU 140 is connected to the hydraulic control device 130 and the internal combustion engine 12, and controls the hydraulic control device 130 and the internal combustion engine 12. The hydraulic control device 130 controls the primary hydraulic chamber control device 135, the drive hydraulic chamber control device 136, and the secondary hydraulic chamber control device 137 based on a control signal from the ECU 140, so that the hydraulic oil supply / discharge valve 110 is controlled. And the hydraulic oil is supplied to or discharged from the primary hydraulic chamber 54, which is one of the clamping pressure generating hydraulic chambers, and at least the gear ratio of the belt-type continuously variable transmission 22 is controlled. Is. The ECU 140 controls the output torque of the internal combustion engine 12 by controlling a fuel injection valve, a spark plug, and a throttle valve (not shown) of the internal combustion engine 12 by a control signal output to the internal combustion engine 12.

  The ECU 140 determines the hydraulic control device 130 and the internal combustion engine based on operating conditions and various data stored in a storage unit (not shown), for example, an optimum fuel consumption curve based on the engine speed and the throttle opening of the throttle valve. 12 is controlled. The ECU 140 is electrically connected to an input rotation speed sensor 150 and an output rotation speed sensor 160.

  The input rotation speed sensor 150 also constitutes a part of the gear ratio detection means. The input rotation speed sensor 150 detects an input rotation speed Nin of a pulley to which driving force from a driving source is input, that is, a primary pulley 50 to which output torque from the internal combustion engine 12 is input. The input rotation speed sensor 150 detects the rotation speed of the primary shaft 51 of the primary pulley 50 and sets the rotation speed of the primary shaft 51 as the input rotation speed Nin. As shown in FIG. 3, the input rotation speed sensor 150 is connected to the ECU 140. Therefore, the input rotation speed Nin detected by the input rotation speed sensor 150 is output to the ECU 140. Note that the input rotation speed sensor 150 is not limited to the rotation speed of the primary shaft 51 set to the input rotation speed Nin. For example, the input rotation speed sensor 150 detects the engine rotation speed Ne of the internal combustion engine 12 and inputs the input rotation from the engine rotation speed Ne. The number Nin may be calculated. As this input rotation speed sensor 150, for example, a pulse-type rotation speed sensor can be used.

  The output rotation speed sensor 160 also constitutes a part of the gear ratio detection means. The output rotation speed sensor 160 detects the output rotation speed Nout of the secondary pulley 60 to which the driving force from the drive source input to the primary pulley 50, that is, the output torque of the internal combustion engine 12 is transmitted via the belt 80. is there. In the first embodiment, the output rotation speed sensor 160 detects the rotation speed of the secondary shaft 61 of the secondary pulley 60 and sets the rotation speed of the secondary shaft 61 as the output rotation speed Nout. The output rotation speed sensor 160 is connected to the ECU 140 as shown in FIG. Therefore, output rotation speed Nout detected by output rotation speed sensor 160 is output to ECU 140. As the output rotation speed sensor 160, for example, a pulse-type rotation speed sensor can be used.

  Here, the ratio between the input rotational speed Nin (in other words, input rotational speed) detected by the input rotational speed sensor 150 and the output rotational speed Nout (in other words, output rotational speed) detected by the output rotational speed sensor 160. Is the gear ratio of the belt type continuously variable transmission 22. That is, the input rotation speed sensor 150 and the output rotation speed sensor 160 detect the gear ratio. Therefore, the ECU 140 receives the input speed Nγ detected by the input speed sensor 150 and the output speed Nout detected by the output speed sensor 160, so that the detected gear ratio γ is input. It becomes.

  The ECU 140 determines the line pressure based on the actual transmission ratio that is the actual actual transmission ratio, the operating conditions such as the target transmission ratio that is the target transmission ratio, and various data stored in the storage unit (not shown). Control signals for the control device 133, the primary hydraulic chamber control device 135, the drive hydraulic chamber control device 136, and the secondary hydraulic chamber control device 137 are generated and output to the hydraulic control device 130. In this way, the ECU 140 controls the line pressure control device 133, the primary hydraulic chamber control device 135, the drive hydraulic chamber control device 136, and the secondary hydraulic chamber control device 137 by the control signal output to the hydraulic control device 130. Thus, the hydraulic control device 130 is set so that the speed ratio γ based on the input speed Nin detected by the input speed sensor 150 and the output speed Nout detected by the output speed sensor 160 becomes the target speed ratio γo. Control.

  Next, the operation of the belt type continuously variable transmission 22 according to the first embodiment will be described. First, a description will be given of general forward and reverse travel of the vehicle 10. When the driver selects a forward position by a shift position device (not shown) provided in the vehicle 10, the ECU 140 turns the forward clutch on and the reverse brake off with hydraulic oil supplied from the hydraulic control device 130, and moves forward and backward. The switching mechanism 20 is controlled. Thereby, the input shaft 18 and the primary shaft 51 will be in a direct connection state. Thereby, the output torque from the internal combustion engine 12 is transmitted to the primary pulley 50, and the primary shaft 51 is rotated in the same direction as the rotation direction of the crankshaft 14 of the internal combustion engine 12. The output torque from the internal combustion engine 12 transmitted to the primary pulley 50 is transmitted to the secondary pulley 60 via the belt 80 and rotates the secondary shaft 61 of the secondary pulley 60.

  The output torque of the internal combustion engine 12 transmitted to the secondary pulley 60 is transmitted from the secondary shaft 61 of the belt-type continuously variable transmission 22 to the speed reducer 24 and from the speed reducer 24 to the drive shaft 32 via the differential device 28. And transmitted to a drive wheel 34 attached to the end of the drive shaft 32. The vehicle 10 moves forward by the drive wheels 34 rotating relative to the road surface.

  On the other hand, when the driver selects the reverse drive position by the shift position device provided in the vehicle 10, the ECU 140 turns off and reverses the forward clutch of the forward / reverse switching mechanism 20 using the hydraulic oil supplied from the hydraulic control device 130. Turn on the brake. Thereby, the primary shaft 51 rotates in the opposite direction to the input shaft 18. As a result, the secondary shaft 61, the speed reduction device 24, the differential device 28, the drive shaft 32, and the like of the secondary pulley 60 rotate in the opposite direction to the case where the driver selects the forward movement position, and the vehicle moves backward.

  Here, the ECU 140 is a map (for example, an optimum fuel consumption curve based on various conditions such as the speed of the vehicle 10 and the accelerator opening of the driver and a map stored in the storage unit of the ECU 140 (for example, the engine speed and the throttle opening of the throttle valve). The transmission ratio of the belt-type continuously variable transmission 22 is controlled via the hydraulic control device 130 so that the operating state of the internal combustion engine 12 is optimized. The ECU 140 sets the target gear ratio γo so that the operation state of the internal combustion engine 12 is optimal, the current state of the primary hydraulic chamber 54 and the secondary hydraulic chamber 64, and the hydraulic pressure stored in the storage unit (not shown). From the relationship between the amount of hydraulic oil flowing between the control device 130 and the primary hydraulic chamber 54 and the hydraulic pressure in the primary hydraulic chamber 54, the primary gear ratio γ of the belt-type continuously variable transmission 22 becomes the target gear ratio γo. The hydraulic pressures of the hydraulic chamber 54 and the secondary hydraulic chamber 64 are calculated. The ECU 140 further discharges the amount of hydraulic oil supplied from the hydraulic control device 130 to the primary hydraulic chamber 54 and the secondary hydraulic chamber 64 from the calculated hydraulic pressure, or discharges from the primary hydraulic chamber 54 and the secondary hydraulic chamber 64 to the hydraulic control device 130. The amount of hydraulic oil to be calculated is calculated, and the hydraulic control device 130 is controlled based on the calculation result.

  Here, the control of the gear ratio of the belt-type continuously variable transmission 22 includes changing the gear ratio and fixing the gear shift (gear ratio γ steady). The change of the gear ratio and the fixing of the gear ratio are performed by controlling the primary hydraulic chamber control device 135, the drive hydraulic chamber control device 136, and the secondary hydraulic chamber control device 137. Note that the control of the gear ratio using the hydraulic control device 130 is performed every control cycle.

  In a state where the gear ratio is not fixed, that is, in a state where the gear ratio is changed, the ECU 140 reduces the drive hydraulic pressure in the drive hydraulic chamber 124 and opens the hydraulic oil supply / discharge valve 110.

  Specifically, the ECU 140 controls the drive hydraulic chamber control device 136 to be OFF. When the drive hydraulic chamber control device 136 is OFF-controlled by the ECU 140, the drive hydraulic chamber 124 is released to atmospheric pressure, and the drive hydraulic pressure in the drive hydraulic chamber 124 becomes substantially atmospheric pressure. Therefore, the valve body 114 of the hydraulic oil supply / discharge valve 110 is separated from the valve seat portion 112 by the biasing force of the spring 126 constituting the actuator 120, and the hydraulic oil supply / discharge valve 110 is opened.

  Next, ECU 140 performs gear ratio change control by hydraulic control device 130. The gear ratio change control is performed mainly by supplying hydraulic oil from the hydraulic control device 130 to the primary hydraulic chamber 54 or discharging hydraulic oil from the primary hydraulic chamber 54 to the outside of the primary pulley 50 via the hydraulic control device 130. The primary movable sheave 53 slides in the axial direction of the primary shaft 51, and the interval between the primary fixed sheave 52 and the primary movable sheave 53, that is, the width of the primary groove 80a is adjusted. As a result, the contact radius of the belt 80 in the primary pulley 50 changes, and there is no gear ratio that is the ratio between the rotation speed of the primary pulley 50, that is, the input rotation speed Nin, and the rotation speed of the secondary pulley 60, that is, the output rotation speed Nout. Controlled in stages (continuous).

  In the secondary pulley 60, the secondary hydraulic chamber control device 137 is controlled by the ECU 140 to regulate the hydraulic pressure in the secondary hydraulic chamber 64, and the belt 80 is sandwiched between the secondary fixed sheave 62 and the secondary movable sheave 63. The belt clamping pressure is adjusted. Thereby, the belt tension of the belt 80 wound between the primary pulley 50 and the secondary pulley 60 is controlled.

  Here, the transmission ratio change control includes an upshift, that is, a transmission ratio decrease change control that decreases the transmission ratio, and a downshift, that is, a transmission ratio increase change control that increases the transmission ratio. Each will be described below.

  The gear ratio reduction change control (upshift control) is performed by supplying hydraulic fluid from the hydraulic control device 130 to the primary hydraulic chamber 54 and sliding (moving) the primary movable sheave 53 to the primary fixed sheave side. That is, the hydraulic control device 130 supplies hydraulic oil to the primary hydraulic chamber 54 via the hydraulic oil supply / discharge valve 110 opened as described above. Specifically, ECU 140 calculates a reduction gear ratio and a transmission speed, and outputs a control signal for the transmission ratio based on these to hydraulic control device 130.

  The supply-side control valve 135a of the primary hydraulic chamber control device 135 is duty-controlled by the ECU 140 and is repeatedly turned on and off to regulate the control hydraulic pressure of the control hydraulic chamber 135o of the supply-side flow rate control valve 135c to a predetermined pressure during supply. Then, a predetermined pressure at the time of supply is introduced into the fourth port 135u of the discharge side flow control valve 135d. Here, the predetermined pressure at the time of supply decreases the supply flow rate controlled by controlling the communication between the second port 135l and the third port 135m by the spool valve opening direction pressing force acting on the spool 135p. It is the pressure which can be set as the supply flow rate based on speed. Accordingly, the supply-side flow rate control valve 135c has a control pressure of the control hydraulic chamber 135o, that is, the spool valve opening direction pressing force based on the predetermined pressure at the time of supply exceeds the spool closing direction pressing force. Moving in one direction, the second port 135l and the third port 135m communicate. As a result, the supply-side flow rate control valve 135c is opened, and the supply flow rate of the hydraulic oil to the primary hydraulic chamber 54 becomes a supply flow rate based on the reduction gear ratio and the shift speed.

  On the other hand, the discharge-side control valve 135b of the primary hydraulic chamber control device 135 is controlled to be turned off by the ECU 140, and the fourth port 135n of the supply-side flow rate control valve 135c and the control hydraulic chamber 135v of the discharge-side flow rate control valve 135d are at atmospheric pressure. To release. Accordingly, since only the spool closing direction pressing force acts on the spool 135w, the discharge-side flow rate control valve 135d is maintained in a state where the spool 135w is positioned in the other direction in the moving direction, and the second port 135s and the third port The port 135t does not communicate. As a result, the discharge-side flow rate control valve 135d remains closed, and the discharge flow rate of the hydraulic oil from the primary hydraulic chamber 54 becomes zero.

  Therefore, the hydraulic oil introduced into the supply-side flow control valve 135c with the line pressure PL is controlled by the supply-side flow control valve 135c to the supply flow rate based on the reduction gear ratio and the transmission speed, and the oil passage R7, the hydraulic oil The oil is supplied to the primary hydraulic chamber 54 via the supply / discharge valve 110, the second oil passage 102 and the first oil passage 86 as supply / discharge passages. Then, the hydraulic oil supplied through the hydraulic oil supply / discharge valve 110 and the like increases the hydraulic pressure in the primary hydraulic chamber 54, and the pressing force that presses the primary movable sheave 53 toward the primary fixed sheave side increases. Slides toward the primary fixed sheave side in the axial direction. As a result, the contact radius of the belt 80 in the primary pulley 50 is increased, the contact radius of the belt 80 in the secondary pulley 60 is decreased, the transmission gear ratio is decreased, the transmission gear ratio is decreased, and the upshift is executed.

  In gear ratio increase change control (downshift control), hydraulic oil is discharged from the primary hydraulic chamber 54 via the hydraulic control device 130, and the primary movable sheave 53 is slid (moved) to the side opposite to the primary fixed sheave side. Is done. That is, the hydraulic control device 130 discharges hydraulic oil from the primary hydraulic chamber 54 via the hydraulic oil supply / discharge valve 110 opened as described above. Specifically, ECU 140 calculates an increase gear ratio and a gear shift speed, and outputs a gear ratio control signal based on these to hydraulic control device 130.

  The supply side control valve 135a of the primary hydraulic chamber control device 135 is controlled OFF by the ECU 140, and the control hydraulic chamber 135o of the supply side flow rate control valve 135c and the fourth port 135u of the discharge side flow rate control valve 135d are released to atmospheric pressure. To do. Therefore, since only the spool closing direction pressing force acts on the spool 135p, the supply-side flow rate control valve 135c is maintained in a state where the spool 135p is located in the other direction in the moving direction. The third port 135m does not communicate. As a result, the supply-side flow rate control valve 135c remains closed, and the supply flow rate of hydraulic oil to the primary hydraulic chamber 54 becomes zero.

  On the other hand, the discharge-side control valve 135b of the primary hydraulic chamber control device 135 is duty-controlled by the ECU 140, repeats ON and OFF, and introduces a predetermined pressure during discharge into the fourth port 135n of the supply-side flow control valve 135c. The control hydraulic pressure of the control hydraulic chamber 135v of the discharge side flow control valve 135d is adjusted to a predetermined pressure at the time of discharge. Here, the predetermined pressure at the time of discharge increases the discharge flow rate controlled by controlling the communication between the second port 135s and the third port 135t by the spool valve opening direction pressing force acting on the spool 135w. It is the pressure that can be the discharge flow rate based on the speed. Accordingly, the discharge-side flow rate control valve 135d is configured so that the spool 135w is moved out of the moving direction because the spool valve opening direction pressing force based on the control hydraulic pressure of the control hydraulic chamber 135v, that is, the predetermined pressure during discharging exceeds the spool closing direction pressing force. The second port 135s communicates with the third port 135t by moving in one direction. As a result, the discharge-side flow rate control valve 135d is opened, and the hydraulic oil discharge flow rate from the primary hydraulic chamber 54 becomes the discharge flow rate based on the reduction gear ratio and the shift speed.

  Therefore, the hydraulic oil in the primary hydraulic chamber 54 passes through the second oil path 102 and the first oil path 86, the hydraulic oil supply / discharge valve 110, the oil path R7, and the branch oil path R71 as supply / discharge paths from the primary hydraulic chamber 54. And flows into the discharge-side flow control valve 135d through the discharge-side flow control valve 135d, and is controlled by the discharge-side flow control valve 135d to the discharge flow rate based on the increase gear ratio and the speed change speed. The oil pan 131 is discharged to the outside of the primary hydraulic chamber 54. Accordingly, the hydraulic oil is discharged from the primary hydraulic chamber 54 via the hydraulic oil supply / discharge valve 110, whereby the hydraulic pressure in the primary hydraulic chamber 54 decreases, and the pressing force that presses the primary movable sheave 53 toward the primary fixed sheave side is increased. The primary movable sheave 53 is slid to the opposite side of the primary fixed sheave side in the axial direction. As a result, the contact radius of the belt 80 in the primary pulley 50 is decreased, the contact radius of the belt 80 in the secondary pulley 60 is increased, the transmission ratio is increased, the increased transmission ratio is obtained, and the downshift is executed.

  On the other hand, ECU 140 performs control to fix the gear ratio, that is, to make the gear ratio steady, when there is no need to change the gear ratio significantly, such as when the traveling state of the vehicle is stable. When ECU 140 determines that the gear ratio is fixed, it closes hydraulic oil supply / discharge valve 110. That is, ECU 140 closes hydraulic oil supply / discharge valve 110 to fix the gear ratio.

  Here, when the hydraulic oil supply / discharge valve 110 is closed and the gear ratio is fixed, that is, when the gear ratio is fixed in the closed state, the hydraulic oil is not supplied to the primary hydraulic chamber 54 and the primary hydraulic chamber is fixed. The operation oil is not discharged from 54, the position of the primary movable sheave 53 in the axial direction with respect to the primary fixed sheave 52 is made constant, and the movement of the primary movable sheave 53 with respect to the primary fixed sheave 52 is restricted.

  When the transmission ratio is fixed, the drive hydraulic pressure in the drive hydraulic chamber 124 is increased, the hydraulic oil supply / discharge valve 110 is closed, and the hydraulic oil is supplied to the primary hydraulic chamber 54 via the hydraulic oil supply / discharge valve 110 and Discharging hydraulic oil from the primary hydraulic chamber 54 via the hydraulic oil supply / discharge valve 110 is prohibited.

  Specifically, the ECU 140 controls the drive hydraulic chamber control device 136 to be ON. When the drive hydraulic chamber control device 136 is ON-controlled by the ECU 140, the constant pressure PS introduced into the drive hydraulic chamber control device 136 is introduced into the drive hydraulic chamber 124, and the drive hydraulic pressure in the drive hydraulic chamber 124 is constant pressure PS. It becomes. Therefore, the valve body 114 of the hydraulic oil supply / discharge valve 110 comes into contact with the valve seat 112 by the hydraulic pressure of the hydraulic oil in the drive hydraulic chamber 124 that has reached the constant pressure PS, and the hydraulic oil supply / discharge valve 110 is closed.

  The supply side control valve 135a of the primary hydraulic chamber control device 135 is controlled OFF by the ECU 140, and the control hydraulic chamber 135o of the supply side flow rate control valve 135c and the fourth port 135u of the discharge side flow rate control valve 135d are released to atmospheric pressure. To do. Accordingly, since only the spool closing direction pressing force acts on the spool 135p, the supply-side flow rate control valve 135c is maintained in a state where the spool 135p is positioned in the other direction in the moving direction, and the second port 135l and the third The port 135m does not communicate. As a result, the supply-side flow rate control valve 135c remains closed, and the supply flow rate of hydraulic oil to the primary hydraulic chamber 54 becomes zero. As a result, the supply of hydraulic oil to the primary hydraulic chamber 54 via the hydraulic oil supply / discharge valve 110 is prohibited.

  On the other hand, the discharge-side control valve 135b of the primary hydraulic chamber control device 135 is controlled to be turned off by the ECU 140, and the fourth port 135n of the supply-side flow rate control valve 135c and the control hydraulic chamber 135v of the discharge-side flow rate control valve 135d are at atmospheric pressure. To release. Accordingly, since only the spool closing direction pressing force acts on the spool 135w, the discharge-side flow rate control valve 135d is maintained in a state where the spool 135w is positioned in the other direction in the moving direction, and the second port 135s and the third port The port 135t does not communicate. As a result, the discharge-side flow rate control valve 135d remains closed, and the discharge flow rate of the hydraulic oil from the primary hydraulic chamber 54 becomes zero. As a result, the discharge of hydraulic oil from the primary hydraulic chamber 54 via the hydraulic oil supply / discharge valve 110 is prohibited.

  Therefore, when the transmission ratio is fixed when the hydraulic oil supply / discharge valve 110 is closed, the supply of the hydraulic oil to the primary hydraulic chamber 54 and the discharge of the hydraulic oil from the primary hydraulic chamber 54 are prohibited, thereby preventing the primary hydraulic chamber. The hydraulic oil in 54 is retained. Here, since the belt tension of the belt 80 changes even when the transmission gear ratio is fixed in the valve-closed state, the contact radius of the belt 80 in the primary pulley 50 tends to change, and the shaft of the primary movable sheave 53 with respect to the primary fixed sheave 52 is changed. The position in the direction may change. However, as described above, since the hydraulic oil is held in the primary hydraulic chamber 54, the primary movable sheave 53 can be moved from the belt 80 even if the position of the primary movable sheave 53 in the axial direction with respect to the primary fixed sheave 52 is changed. The hydraulic pressure of the primary hydraulic chamber 54 also changes in accordance with the belt reaction force acting via the sheave 53, so that the position of the primary movable sheave 53 in the axial direction with respect to the primary fixed sheave 52 is maintained constant. Therefore, in order to keep the position of the primary movable sheave 53 in the axial direction with respect to the primary fixed sheave 52 constant, it is not necessary to increase the hydraulic pressure of the primary hydraulic chamber 54 by supplying hydraulic oil to the primary hydraulic chamber 54. . As a result, when the transmission gear ratio is fixed in the valve-closed state, the oil pump 132 does not have to be driven in order to supply the hydraulic oil to the primary hydraulic chamber 54. Therefore, an increase in driving loss of the oil pump 132 can be suppressed. it can.

  By the way, in the belt-type continuously variable transmission 22 as described above, the speed of the vehicle 10 equipped with the belt-type continuously variable transmission 22 decreases, and accordingly, the pulley on the driving wheel 34 side, that is, the driven pulley. When the rotational speed of the secondary pulley 60 is also reduced, for example, the detection accuracy of the rotational speed detected by the output rotational speed sensor 160 may be reduced. For this reason, since the detection accuracy of the actual gear ratio based on the rotation speed of the primary pulley 50 and the rotation speed of the secondary pulley 60 is reduced, for example, the accuracy of the gear ratio control may be reduced and drivability may be reduced. .

  Therefore, in the belt-type continuously variable transmission 22 of the present embodiment, when the speed of the vehicle 10 becomes equal to or lower than a predetermined speed set in advance, the hydraulic control device 130 increases the drive hydraulic pressure and the actuator 120 supplies and discharges hydraulic oil. The drivability is improved by closing the valve 110.

  Here, the predetermined speed set in advance with respect to the speed of the vehicle 10 is a speed at which the detection accuracy of the input rotation speed sensor 150 and the output rotation speed sensor 160 decreases and the detection accuracy of the actual gear ratio decreases. The very low speed immediately before the vehicle 10 stops.

  In the belt type continuously variable transmission 22 of the present embodiment, a vehicle speed sensor 170 (see FIG. 3) for detecting the speed of the vehicle 10 is electrically connected to the ECU 140, and the ECU 140 detects the speed detected by the vehicle speed sensor 170. Based on this, it is determined whether or not the speed of the vehicle 10 is equal to or lower than a predetermined speed. Note that the speed of the vehicle 10 is a value according to the number of rotations of the pulley on the driving force output side, that is, the secondary pulley 60 to which the driving wheel 34 is connected, and therefore the secondary pulley detected by the output rotation number sensor 160. The speed of the vehicle 10 may be detected based on the number of rotations of 60. That is, the ECU 140 determines whether the rotation speed of the secondary pulley 60 detected by the output rotation speed sensor 160 is equal to or less than a predetermined rotation speed that is substantially preset with respect to the speed of the vehicle 10. It is also possible to determine whether the speed is equal to or less than a predetermined speed.

  FIG. 4 is a flowchart for explaining low-vehicle-speed valve closing control of the belt-type continuously variable transmission according to Embodiment 1 of the present invention, and FIG. 5 is a flowchart of the belt-type continuously variable transmission according to Embodiment 1 of the present invention. It is a time chart explaining an example of the valve closing control at the time of vehicle speed, the vertical axis is the vehicle speed V and the drive hydraulic pressure Pcv of the drive hydraulic chamber 124, and the horizontal axis is the time axis. Hereinafter, the low-speed closing control of the belt-type continuously variable transmission 22 will be described with reference to FIGS. This control routine is repeatedly executed at a control cycle of several ms to several tens of ms.

  First, the ECU 140 determines whether or not the vehicle speed V is equal to or lower than a predetermined speed A set in advance based on the speed of the vehicle 10 detected by the vehicle speed sensor 170, that is, the vehicle speed V (S100).

  When the ECU 140 determines that the vehicle speed V is equal to or lower than the predetermined speed A (S100: Yes), the hydraulic control device 130 closes the hydraulic oil supply / discharge valve 110 (S102), and ends the low vehicle speed valve closing control. To do. That is, as shown in FIG. 5, when the vehicle speed V becomes equal to or lower than the predetermined speed A at time t11, the hydraulic control device 130 is controlled by the ECU 140 so that the drive hydraulic chamber control device 136 is turned on. The constant pressure PS introduced into the control device 136 is introduced into the drive hydraulic chamber 124, whereby the drive hydraulic pressure Pcv of the drive hydraulic chamber 124 is set to the constant pressure PS. Therefore, the valve body 114 of the hydraulic oil supply / discharge valve 110 comes into contact with the valve seat portion 112 by the hydraulic pressure Pcv of the hydraulic oil in the drive hydraulic chamber 124 that has reached the constant pressure PS, and the hydraulic oil supply / discharge valve 110 is closed.

  When the ECU 140 determines that the vehicle speed V is greater than the predetermined speed A (S100: No), the ECU 140 executes normal gear ratio control (S104), and ends the low vehicle speed valve closing control.

  According to the belt-type continuously variable transmission 22 according to the embodiment of the present invention described above, the primary pulley 50 and the secondary pulley 60 as the two pulleys of the vehicle 10 and the primary pulley 50 and the secondary pulley 60 are wound around. The primary hydraulic chamber 54 and the secondary hydraulic chamber 64 that are formed in the belt 80 that transmits the driving force from the internal combustion engine 12, the primary pulley 50, and the secondary pulley 60, respectively, and generates belt clamping pressure against the belt 80 by hydraulic pressure, The hydraulic oil is supplied to the primary hydraulic chamber 54 as one clamping pressure generating hydraulic chamber, and the first oil passage 86 and the second oil passage 102 as supply / discharge paths for discharging the hydraulic oil from the primary hydraulic chamber 54 are supplied. Direction of discharging hydraulic oil from the primary hydraulic chamber 54 provided in the second oil passage 102 as a discharge path The hydraulic oil supply / discharge valve 110 and the hydraulic oil pressure of the hydraulic oil in the drive hydraulic chamber 124 move the piston 122 to close the hydraulic oil supply / discharge valve 110 in the direction of supplying the hydraulic oil to the primary hydraulic chamber 54. A valve-capable actuator 120, a primary pulley 50 as two pulleys, an input speed sensor 150 as a speed ratio detecting means capable of detecting a speed ratio that is a speed ratio of the secondary pulley 60, an output speed sensor 160; By controlling the supply hydraulic pressure that is the hydraulic pressure of the hydraulic oil supplied to the primary hydraulic chamber 54 and the drive hydraulic pressure that is the hydraulic oil pressure of the drive hydraulic chamber 124, the hydraulic oil supply and discharge valve 110 is opened by reducing the drive hydraulic pressure. The hydraulic oil is supplied to the primary hydraulic chamber 54, or the hydraulic oil is discharged from the primary hydraulic chamber 54, and the input rotational speed as the gear ratio detecting means While changing the gear ratio detected by the sensor 150 and the output speed sensor 160 to the target gear ratio, the hydraulic oil pressure is increased by closing the hydraulic oil supply / discharge valve 110 by the actuator 120 by increasing the drive hydraulic pressure. The hydraulic control device 130 closes the hydraulic oil supply / discharge valve 110 by the actuator 120 by increasing the drive hydraulic pressure when the speed of the vehicle 10 is equal to or lower than a predetermined speed set in advance. Let

  Accordingly, the speed of the vehicle 10 on which the belt type continuously variable transmission 22 is mounted is reduced, and accordingly, the rotational speed of the pulley on the driving wheel 34 side, that is, the secondary pulley 60 that is the driven pulley is also reduced. Even when the detection accuracy of the rotational speed detected by the output rotational speed sensor 160 is reduced and the detection accuracy of the actual gear ratio based on the rotational speed of the primary pulley 50 and the rotational speed of the secondary pulley 60 is reduced. When the speed of the vehicle 10 is equal to or lower than a predetermined speed set in advance, the drive hydraulic pressure is increased and the hydraulic oil supply / discharge valve 110 is closed by the actuator 120, whereby the primary via the hydraulic oil supply / discharge valve 110 is closed. Supply of hydraulic oil to the hydraulic chamber 54 and discharge of hydraulic oil from the primary hydraulic chamber 54 via the hydraulic oil supply / discharge valve 110 are prohibited, and a belt-type continuously variable transmission. Increase speed ratio speed ratio is downshifted in accordance with the deceleration of the vehicle 10 in the 2, for example, it can be fixed in the vicinity maximum speed ratio.

  At this time, as described above, even if the belt tension of the belt 80 changes and the contact radius of the belt 80 on the primary pulley 50 changes, the hydraulic oil supply / discharge valve 110 is closed, so that the primary hydraulic pressure Since the hydraulic oil is held in the chamber 54, the hydraulic pressure in the primary hydraulic chamber 54 also changes according to the belt reaction force acting from the belt 80 via the primary movable sheave 53, so that the primary movable sheave 53 is changed. The position in the axial direction with respect to the primary fixed sheave 52 is maintained constant. Therefore, the belt-type continuously variable transmission 22 can maintain a gear ratio when the hydraulic oil supply / discharge valve 110 is closed, for example, a gear ratio in the vicinity of the maximum gear ratio.

  For example, the hydraulic control device 130 controls the supply-side control valve 135a and the discharge-side control valve 135b to be OFF by the hydraulic control device 130 without closing the hydraulic oil supply / discharge valve 110 when the vehicle 10 is at a low speed. In other words, in the hydraulic circuit of the hydraulic control device 130, hydraulic oil is supplied from the supply-side control valve 135a and the discharge-side control valve 135b to the primary hydraulic chamber 54 side. In addition, the supply hydraulic pressure to the primary hydraulic chamber 54 and the supply hydraulic pressure to the secondary hydraulic chamber 64 are regulated based on a predetermined pressure regulation formula, and the supply hydraulic pressure to the primary hydraulic chamber 54 can be prevented from belt slip. By executing the closing control to switch to the predetermined hydraulic pressure, the gear ratio in the belt-type continuously variable transmission 22 is reduced as the vehicle 10 is decelerated. Unshifuto been increased transmission ratio, for example, can be fixed in the vicinity maximum speed ratio. However, in this case, for example, there is a possibility that a slight shift, for example, a slight upshift may occur due to the influence of variations in the mechanical accuracy of the spool of the hydraulic control device 130. In this case, as described above, the speed of the vehicle 10 equipped with the belt-type continuously variable transmission 22 decreases, and the detection accuracy of the actual gear ratio based on the rotation speed of the primary pulley 50 and the rotation speed of the secondary pulley 60 is improved. If it is lowered, there is a possibility that the deviation between the actual gear ratio and the target gear ratio cannot be detected.

  On the other hand, the belt-type continuously variable transmission 22 of the present embodiment increases the drive hydraulic pressure when the speed of the vehicle 10 is equal to or lower than a predetermined speed set in advance, and the hydraulic oil supply / discharge valve 110 is driven by the actuator 120. Is closed, the speed ratio in the belt-type continuously variable transmission 22 can be reliably fixed in the vicinity of the increased speed ratio that is downshifted as the vehicle 10 is decelerated, for example, in the vicinity of the maximum speed ratio. As a result, for example, when the vehicle 10 restarts after the vehicle 10 is stopped, it is possible to reliably start at a gear ratio close to the maximum gear ratio, so that it is possible to prevent a torque shortage at the time of starting. Since it can prevent that a slip arises, drivability can be improved and reliability can be improved.

  The belt-type continuously variable transmission 22 increases the drive hydraulic pressure and closes the hydraulic oil supply / discharge valve 110 by the actuator 120 when the speed of the vehicle 10 is equal to or lower than a predetermined speed set in advance. You may use together the above-mentioned closing control.

  FIG. 6 is a flowchart for explaining low-vehicle-speed valve closing control of the belt-type continuously variable transmission according to the first modification of the present invention, and FIG. 7 is a flowchart of the belt-type continuously variable transmission according to the first modification of the present invention. It is a time chart explaining an example of valve closing control at the time of vehicle speed.

  When the ECU 140 of the belt-type continuously variable transmission 22A according to this modification determines that the vehicle speed V is equal to or lower than the predetermined speed A (S100: Yes), the ECU 140 executes the closing control by the hydraulic control device 130 (S101A). The hydraulic oil supply / discharge valve 110 is closed (S102), and the low-vehicle-speed valve closing control is terminated.

  That is, as shown in FIG. 7, when the vehicle speed V becomes equal to or lower than the predetermined speed A at time t12, the hydraulic control device 130 controls the supply side control valve 135a and the discharge side control valve 135b to be OFF as the closing control. Thus, both the output hydraulic pressure PDS1 of the supply side control valve 135a and the output hydraulic pressure PDS2 of the discharge side control valve 135b become zero. Then, supply of hydraulic oil to the primary hydraulic chamber 54 and discharge of hydraulic oil from the primary hydraulic chamber 54 are prohibited, and in the hydraulic circuit of the hydraulic control device 130, the primary hydraulic chamber is supplied from the supply side control valve 135a and the discharge side control valve 135b. 54, after confining the hydraulic oil to the secondary hydraulic chamber 64 side, the hydraulic pressure supplied to the primary hydraulic chamber 54 and the hydraulic pressure supplied to the secondary hydraulic chamber 64 are regulated based on a predetermined pressure regulation type, and the primary hydraulic chamber 54 is supplied. The closing control is performed to switch the supply hydraulic pressure to a predetermined hydraulic pressure that can prevent belt slip. Almost in parallel with this control, the ECU 140 is controlled so that the drive hydraulic chamber control device 136 is turned on, and the constant pressure PS introduced into the drive hydraulic chamber control device 136 is introduced into the drive hydraulic chamber 124. Thus, the drive hydraulic pressure Pcv of the drive hydraulic chamber 124 is set to a constant pressure PS. Therefore, the valve body 114 of the hydraulic oil supply / discharge valve 110 comes into contact with the valve seat portion 112 by the hydraulic pressure Pcv of the hydraulic oil in the drive hydraulic chamber 124 that has reached the constant pressure PS, and the hydraulic oil supply / discharge valve 110 is closed. Note that, during the period before time t12, the downshift in the normal gear ratio control accompanying the deceleration of the vehicle 10 is being executed, so the output hydraulic pressure PDS2 of the discharge side control valve 135b is reduced to the reduction gear ratio and the gear shift speed. The hydraulic pressure is in accordance with the discharge flow rate of the hydraulic oil from the primary hydraulic chamber 54 based on it.

  Even in this case, the belt-type continuously variable transmission 22A according to the first modification can reliably start at a speed ratio near the maximum speed ratio when the vehicle 10 restarts after the vehicle 10 stops, for example. Since it is possible to prevent the torque from becoming insufficient at the time of starting, and to prevent the occurrence of belt slip, drivability can be improved and reliability can be improved.

(Embodiment 2)
FIG. 8 is a conceptual diagram schematically showing a schematic configuration of a hydraulic control device for a belt-type continuously variable transmission according to Embodiment 2 of the present invention, and FIG. 9 is a belt-type continuously variable transmission according to Embodiment 2 of the present invention. FIG. 10 is a time chart for explaining an example of the low-speed valve closing control of the belt-type continuously variable transmission according to the second embodiment of the present invention. Is a vehicle speed V, a braking force G, a gear ratio γ, a drive hydraulic pressure Pcv, and output hydraulic pressures PDS1 and PDS2, and a horizontal axis is a time axis. The belt-type continuously variable transmission according to the second embodiment has substantially the same configuration as the belt-type continuously variable transmission according to the first embodiment, but includes a prohibiting unit. Is different. In addition, about the structure, effect | action, and effect which are common in embodiment mentioned above, while overlapping description is abbreviate | omitted as much as possible, the same code | symbol is attached | subjected.

  In the belt-type continuously variable transmission 222 according to this embodiment, the ECU 140 functions as a prohibiting unit of the present invention.

  The ECU 140 according to the present embodiment detects the gear ratio when the speed of the vehicle 10 is equal to or lower than a preset predetermined speed, when the braking force when the vehicle 10 stops is larger than the preset predetermined braking force, or when the speed ratio is detected. When the speed ratio detected by the input speed sensor 150 and the output speed sensor 160 as means is smaller than a predetermined speed ratio set in advance, the hydraulic control device 130 is controlled to close the hydraulic oil supply / discharge valve 110. By prohibiting, the drivability is further improved.

  Here, the predetermined braking force set in advance with respect to the braking force of the vehicle 10 may be such that, for example, the gear ratio of the belt-type continuously variable transmission 222 is not downshifted to the vicinity of the maximum gear ratio due to the sudden stop of the vehicle 10. It is a characteristic braking force. Further, the predetermined speed ratio set in advance with respect to the speed ratio detected by the input speed sensor 150 and the output speed sensor 160 is a speed ratio that can ensure good startability of the vehicle 10.

  In the belt-type continuously variable transmission 222 of the present embodiment, an acceleration sensor 180 (see FIG. 8) for detecting the acceleration of the vehicle 10 is electrically connected to the ECU 140, and the ECU 140 detects the acceleration detected by the acceleration sensor 180. It is determined whether or not the braking force when the vehicle 10 stops is greater than a predetermined braking force based on the braking force corresponding to. Further, ECU 140 determines whether or not this actual speed ratio is smaller than a predetermined speed ratio based on the actual speed ratio detected by input speed sensor 150 and output speed sensor 160. Hereinafter, the low-speed valve closing control of the belt type continuously variable transmission 222 will be described with reference to FIGS. 9 and 10.

  First, the ECU 140 determines whether the vehicle speed V is equal to or lower than a predetermined speed A set in advance based on the vehicle speed V detected by the vehicle speed sensor 170 (S200).

  When the ECU 140 determines that the vehicle speed V is equal to or less than the predetermined speed A (S200: Yes), the ECU 140 determines the speed ratio γ detected by the input speed sensor 150 and the output speed sensor 160 and the braking force G detected by the acceleration sensor 180. Based on this, it is determined whether or not the gear ratio γ is equal to or greater than the predetermined gear ratio B and the braking force G when the vehicle 10 stops is equal to or less than the predetermined braking force G1 (S202). Here, ECU 140 may use speed ratio γ in the previous control cycle.

  The ECU 140 determines that the speed ratio γ is equal to or greater than the predetermined speed ratio B and the braking force G when the vehicle 10 stops is equal to or less than the predetermined braking force G1 (S202: Yes), that is, as shown in FIG. When the vehicle speed V becomes equal to or lower than the predetermined speed A at time t21 and the speed ratio γ is equal to or higher than the predetermined speed ratio B and the braking force G when the vehicle 10 stops is equal to or lower than the predetermined braking force G1, The device 130 executes the closing control (S204), closes the hydraulic oil supply / discharge valve 110 (S206), and ends the low vehicle speed closing control.

  When the ECU 140 determines that the speed ratio γ is smaller than the predetermined speed ratio B or that the braking force G when the vehicle 10 stops is greater than the predetermined braking force G1 (S202: No), the hydraulic pressure control device 130 drives the hydraulic pressure. The chamber controller 136 is kept OFF, the constant pressure PS is prohibited from being introduced into the drive hydraulic chamber 124, the hydraulic oil supply / discharge valve 110 is prohibited from closing (S208), and the hydraulic controller 130 (S210), and the low-vehicle-speed valve closing control is terminated.

  When the ECU 140 determines that the vehicle speed V is greater than the predetermined speed A (S200: No), the ECU 140 executes normal gear ratio control (S212), and ends the low vehicle speed valve closing control.

  According to the belt-type continuously variable transmission 222 according to the embodiment of the present invention described above, when the speed of the vehicle 10 is equal to or lower than a predetermined speed set in advance, the speed ratio is equal to or higher than the predetermined speed ratio and the vehicle 10 When the braking force at the time of stopping is equal to or less than a predetermined braking force, the drive hydraulic pressure is increased and the hydraulic oil supply / discharge valve 110 is closed by the actuator 120, whereby the gear ratio in the belt type continuously variable transmission 222 is increased. The increase gear ratio downshifted as the vehicle 10 decelerates, for example, near the maximum gear ratio, can be reliably fixed. As a result, for example, when the vehicle 10 restarts after the vehicle 10 is stopped, it is possible to reliably start at a gear ratio close to the maximum gear ratio, so that it is possible to prevent the torque from becoming insufficient at the time of starting. Since it can prevent that a slip arises, drivability can be improved and reliability can be improved.

  Furthermore, according to the belt-type continuously variable transmission 222 according to the embodiment of the present invention described above, the braking force when the vehicle 10 stops when the speed of the vehicle 10 falls below a predetermined speed set in advance. Is larger than a predetermined braking force set in advance, or when the gear ratio detected by the input rotation speed sensor 150 and the output rotation speed sensor 160 as a gear ratio detection means is smaller than a predetermined gear ratio set in advance, An ECU 140 that controls the hydraulic control device 130 to prohibit the closing of the hydraulic oil supply / discharge valve 110 is provided.

  Therefore, by prohibiting the closing of the hydraulic oil supply / discharge valve 110 by the ECU 140 when the gear ratio is smaller than the predetermined gear ratio or when the braking force when the vehicle 10 stops is larger than the predetermined braking force, for example, When there is a possibility that the speed ratio of the belt type continuously variable transmission 222 is not downshifted to the vicinity of the maximum speed ratio due to a sudden stop of the vehicle 10, the speed ratio of the belt type continuously variable transmission 222 is Since it is possible to prevent the gear ratio from being fixed to a small gear ratio where good startability cannot be ensured, drivability can be further improved and reliability can be further improved.

  FIG. 11 is a flowchart for explaining the low-speed closing control of the belt type continuously variable transmission according to the second modification of the present invention.

  As shown in FIG. 11, the belt-type continuously variable transmission 222A according to the second modification is closed after the hydraulic oil control device 130 is controlled by the ECU 140 to prohibit the hydraulic oil supply / discharge valve 110 from being closed (S208). Control (S210A) that raises the hydraulic pressure supplied to the secondary hydraulic chamber 64 may be executed instead of the control (S210, see FIG. 9).

  In this case, as the hydraulic pressure in the secondary hydraulic chamber 64 increases, the pressing force that presses the secondary movable sheave 63 toward the secondary fixed sheave 62 increases, and the secondary movable sheave 63 slides toward the secondary fixed sheave 62. As a result, belt slip can be reliably prevented, and the contact radius of the belt 80 in the secondary pulley 60 increases, and the belt tension increases and the belt reaction force acting on the primary movable sheave 53 from the belt 80 also increases. As a result, the primary movable sheave 53 slides on the side opposite to the primary fixed sheave 52 side, and the contact radius of the belt 80 on the primary pulley 50 decreases. As a result, the transmission gear ratio is increased, the transmission gear ratio is increased, downshifting is executed, and the transmission gear ratio of the belt type continuously variable transmission 222A can be downshifted to the vicinity of the maximum transmission gear ratio that can ensure good startability. Therefore, startability can be improved, drivability can be further improved, and reliability can be further improved.

  The belt-type continuously variable transmission according to the above-described embodiment of the present invention is not limited to the above-described embodiment, and various modifications can be made within the scope described in the claims.

  In the above description, the gear ratio detection means has been described as being the input rotation speed sensor 150 and the output rotation speed sensor 160. However, the present invention is not limited to this, and various known speed ratio detection means may be used.

  In the above description, the hydraulic oil supply / discharge valve 110 has been described as being provided in the second oil path 102 that forms part of the supply / discharge path. However, the hydraulic oil supply / discharge valve 110 is provided in the first oil path 86 that forms part of the supply / discharge path. It may be done. That is, the hydraulic oil supply / discharge valve 110 may be provided in the first oil passage 86 inside the primary shaft 51. In this case, for example, the actuator 120 may be provided in the first oil passage 86 inside the primary shaft 51 similarly to the hydraulic oil supply / discharge valve 110. That is, the switching mechanism 100 including the hydraulic oil supply / discharge valve 110 and the actuator 120 may be provided inside the primary shaft 51 and coaxially with the primary shaft 51.

  As described above, the belt-type continuously variable transmission according to the present invention can improve drivability, and is suitable for application to various belt-type continuously variable transmissions.

It is a schematic block diagram of the vehicle carrying the belt type continuously variable transmission which concerns on Embodiment 1 of this invention. It is a typical sectional view showing a schematic structure of a primary pulley of a belt type continuously variable transmission concerning Embodiment 1 of the present invention. It is a typical sectional view showing a schematic structure of a primary pulley of a belt type continuously variable transmission concerning Embodiment 1 of the present invention. 1 is a conceptual diagram schematically showing a schematic configuration of a hydraulic control device for a belt-type continuously variable transmission according to a first embodiment of the present invention. 3 is a flowchart illustrating valve closing control at a low vehicle speed of the belt-type continuously variable transmission according to the first embodiment of the present invention. It is a time chart explaining an example of the valve closing control at the time of low vehicle speed of the belt type continuously variable transmission according to the first embodiment of the present invention. It is a flowchart explaining the valve closing control at the time of the low vehicle speed of the belt-type continuously variable transmission which concerns on the modification 1 of this invention. It is a time chart explaining an example of the valve closing control at the time of the low vehicle speed of the belt-type continuously variable transmission which concerns on the modification 1 of this invention. It is a conceptual diagram which shows typically schematic structure of the hydraulic control apparatus of the belt-type continuously variable transmission which concerns on Embodiment 2 of this invention. It is a flowchart explaining the valve closing control at the time of the low vehicle speed of the belt-type continuously variable transmission which concerns on Embodiment 2 of this invention. It is a time chart explaining an example of the valve closing control at the time of low vehicle speed of the belt-type continuously variable transmission which concerns on Embodiment 2 of this invention. It is a flowchart explaining the valve closing control at the time of the low vehicle speed of the belt-type continuously variable transmission which concerns on the modification 2 of this invention.

Explanation of symbols

10 Vehicle 12 Internal combustion engine (drive source)
22, 22A, 222, 222A Belt type continuously variable transmission 34 Drive wheel 50 Primary pulley (pulley)
54 Primary hydraulic chamber (clamping pressure generating hydraulic chamber)
60 Secondary pulley (pulley)
64 Secondary hydraulic chamber (clamping pressure generating hydraulic chamber)
80 Belt 86 First oil passage (supply / discharge route)
102 Second oil passage (supply / discharge route)
110 Hydraulic oil supply / discharge valve 120 Actuator 122 Piston 124 Drive hydraulic chamber 130 Hydraulic control device (hydraulic control means)
140 ECU (prohibited means)
150 Input rotational speed sensor (speed ratio detecting means)
160 Output speed sensor (speed ratio detecting means)

Claims (2)

Two pulleys mounted on the vehicle;
A belt that is wound around each pulley and transmits a driving force from a driving source;
A clamping pressure generating hydraulic chamber formed in each pulley and generating a belt clamping pressure with respect to the belt by hydraulic pressure;
A supply / discharge path for supplying hydraulic oil to one of the clamping pressure generating hydraulic chambers and discharging the hydraulic oil from the one clamping pressure generating hydraulic chamber;
A hydraulic oil supply / discharge valve provided in the supply / discharge path and capable of opening the hydraulic oil in a direction of discharging the hydraulic oil from the one clamping pressure generating hydraulic chamber;
An actuator capable of closing the hydraulic oil supply / discharge valve in the direction of supplying hydraulic oil to the one clamping pressure generating hydraulic chamber by moving the piston by the hydraulic pressure of the hydraulic oil in the drive hydraulic chamber;
Gear ratio detecting means capable of detecting a gear ratio which is a rotation speed ratio of the two pulleys;
The hydraulic pressure of the hydraulic oil supplied to the one clamping pressure generating hydraulic chamber and the driving hydraulic pressure of the hydraulic oil in the driving hydraulic chamber are controlled, and the operation is performed by reducing the driving hydraulic pressure. An oil supply / discharge valve is opened to supply hydraulic oil to the one clamping pressure generating hydraulic chamber, or the hydraulic oil is discharged from the one clamping pressure generating hydraulic chamber and the gear ratio detected by the gear ratio detecting means is set. A hydraulic control means for closing the hydraulic oil supply / discharge valve by the actuator and fixing the transmission ratio by increasing the drive hydraulic pressure while changing to a target transmission ratio;
The hydraulic control means causes the hydraulic oil supply / discharge valve to be closed by the actuator by increasing the driving hydraulic pressure when the speed of the vehicle is equal to or lower than a predetermined speed set in advance. ,
Belt type continuously variable transmission. When the speed of the vehicle is equal to or lower than a predetermined speed set in advance, when the braking force when the vehicle stops is larger than a predetermined braking power set in advance, or the speed change detected by the speed ratio detecting means When the ratio is smaller than a predetermined speed ratio set in advance, the hydraulic control means is controlled to comprise a prohibiting means for prohibiting the closing of the hydraulic oil supply / discharge valve,
The belt-type continuously variable transmission according to claim 1.

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