JP2013137105A - Belt-type continuously variable transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a belt-type continuously variable transmission which can be improved in product reliability by effectively performing fail-safe operation of a hydraulic oil supply/discharge valve.SOLUTION: The belt-type continuously variable transmission 22 is configured to open the hydraulic oil supply/discharge valve 110 and also to allow a hydraulic control device 130 to supply a hydraulic oil of a predetermined supply hydraulic pressure Pin to a movable sheave 53, during transition of changing a gear ratio, and accordingly the movable sheave 53 is driven to control the clamping force of a belt 80. An upper limit value of the shifting speed of the gear ratio is set when the holding operation of a valve opening state of the hydraulic oil supply/discharge valve 110 is highly likely to fail.

Description

  The present invention relates to a belt-type continuously variable transmission, and more particularly to a belt-type continuously variable transmission that can improve product reliability by effectively performing fail-safe operation of a hydraulic oil supply / discharge valve.

  In recent years, belt-type continuously variable transmissions include a movable sheave that is driven by hydraulic oil to change the clamping pressure of the belt, a hydraulic control device that controls the hydraulic pressure of the hydraulic oil, and a hydraulic fluid that is transmitted from the hydraulic control device to the movable sheave. A hydraulic oil supply / discharge valve that is disposed on the oil passage and regulates the flow of the hydraulic oil. When the transmission gear ratio changes, the hydraulic oil supply / discharge valve opens, and the hydraulic control device supplies hydraulic oil having a predetermined supply hydraulic pressure to the movable sheave via the hydraulic oil supply / discharge valve. As a result, the movable sheave is driven to control the clamping pressure of the belt (normally open fluid confining sheave positioning mechanism). As a conventional belt-type continuously variable transmission that employs such a configuration, a technique described in Patent Document 1 is known.

JP 2007-57033 A

  Here, at the time of the shift of the gear ratio, the hydraulic oil supply / discharge valve is set to the normally open state as described above. However, the aging of the spring supporting the valve body of the hydraulic oil supply / discharge valve and excessive fluid force (fluid force due to hydraulic oil flow rate exceeding the assumed range, hydraulic fluid high viscosity at low oil temperature, etc.) Therefore, it can be assumed that the open state of the hydraulic oil supply / discharge valve is not properly maintained. In such a case, the gear ratio transition is not executed or is not continued, which is not preferable. Also, if the hydraulic oil supply / discharge valve fails and closes when the gear ratio is on the high speed side, downshifting cannot be performed, so the necessary driving force may not be ensured when the vehicle restarts or re-accelerates. There is.

  Therefore, the present invention has been made in view of the above, and provides a belt-type continuously variable transmission that can improve the reliability of a product by effectively performing fail-safe operation of a hydraulic oil supply / discharge valve. Objective.

  To achieve the above object, a continuously variable transmission according to the present invention includes a movable sheave that is driven by hydraulic oil to change the clamping pressure of the belt, a hydraulic control device that controls the hydraulic pressure of the hydraulic oil, and the hydraulic control device. A belt-type continuously variable transmission that is disposed on an oil passage of hydraulic oil from the movable sheave to the movable sheave and that regulates the flow of the hydraulic oil, at the time of a change in gear ratio, When the supply / discharge valve is opened and the hydraulic control device supplies hydraulic oil having a predetermined supply hydraulic pressure Pin to the movable sheave, the movable sheave is driven to control the clamping pressure of the belt, and The upper limit value of the transmission speed of the transmission ratio is set when there is a high possibility that the holding operation of the opened state of the hydraulic oil supply / discharge valve will fail.

  In the belt-type continuously variable transmission according to the present invention, when there is a high possibility that the holding operation of the hydraulic oil supply / discharge valve in the open state is likely to fail, an upper limit value of the transmission speed of the transmission ratio is set to change the transmission ratio. Is done. In such a configuration, a situation in which the gear ratio does not change during the failure of the hydraulic oil supply / discharge valve is avoided. Thereby, the fail safe of the hydraulic oil supply / discharge valve is effectively performed, and there is an advantage that the reliability of the product is improved.

FIG. 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. FIG. 2-1 is a schematic cross-sectional view illustrating a schematic configuration of a primary pulley of the belt-type continuously variable transmission according to the first embodiment of the present invention. FIG. 2-2 is a schematic cross-sectional view illustrating a schematic configuration of a primary pulley of the belt-type continuously variable transmission according to the first embodiment of the present invention. FIG. 3 is a conceptual diagram schematically showing a schematic configuration of the hydraulic control device for the belt-type continuously variable transmission according to the first embodiment of the present invention. FIG. 4-1 is a flowchart for explaining gear ratio control of the belt-type continuously variable transmission according to the first embodiment of the present invention. FIG. 4-2 is a time chart illustrating an example of gear ratio control of the belt-type continuously variable transmission according to the first embodiment of the present invention. FIGS. 5-1 is a flowchart explaining the gear ratio control of the belt type continuously variable transmission according to the second embodiment of the present invention. FIG. 5-2 is a time chart for explaining an example of gear ratio control of the belt-type continuously variable transmission according to the second embodiment of the present invention. FIG. 6 is a gear ratio map of the belt-type continuously variable transmission according to the second embodiment of the present invention. FIG. 7-1 is a flowchart for explaining gear ratio control of the belt-type continuously variable transmission according to the third embodiment of the present invention. FIG. 7-2 is a time chart for explaining an example of gear ratio control of the belt-type continuously variable transmission according to the third embodiment of the present invention. FIG. 8 is a conceptual diagram showing a belt type continuously variable transmission according to Embodiment 2 of the present invention. FIG. 9 is a flowchart showing the operation of the belt type continuously variable transmission according to the fourth embodiment of the present invention. FIG. 10 is a flowchart showing the operation of the belt type continuously variable transmission according to the fourth embodiment of the present invention. FIG. 11 is a flowchart showing the operation of the belt-type continuously variable transmission according to the fifth embodiment of the present invention. FIG. 12 is a time chart showing the operation of the belt type continuously variable transmission according to the fifth embodiment of the present invention. FIG. 13 is a flowchart showing the operation of the belt type continuously variable transmission according to the sixth embodiment of the present invention. FIG. 14 is a time chart showing the operation of the belt type continuously variable transmission according to the sixth embodiment of the present invention. FIG. 15 is an explanatory view showing the operation of the belt-type continuously variable transmission according to the seventh embodiment of the present invention. FIG. 16 is a flowchart showing the operation of the belt type continuously variable transmission according to the seventh embodiment of the present invention. FIG. 17 is a time chart showing the operation of the belt type continuously variable transmission according to the seventh embodiment of the present invention. FIG. 18 is an explanatory view showing a modified example of the belt-type continuously variable transmission according to the seventh embodiment of the present invention. FIG. 19 is a flowchart showing the operation of the belt-type continuously variable transmission according to the eighth embodiment of the present invention. FIG. 20 is a time chart showing the operation of the belt-type continuously variable transmission according to the eighth embodiment of the present invention. FIG. 21 is a flowchart showing the operation of the belt type continuously variable transmission according to the ninth embodiment of the present invention. FIG. 22 is a time chart showing the operation of the belt type continuously variable transmission according to the ninth embodiment of the present invention.

  Hereinafter, the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments. Further, the constituent elements of this embodiment include those that can be replaced while maintaining the identity of the invention and that are obvious for replacement. In addition, a plurality of modifications described in this embodiment can be arbitrarily combined within a range obvious to those skilled in the art.

  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 schematic sectional view showing a schematic configuration of a primary pulley of a transmission, FIG. 3 is a conceptual diagram schematically showing a schematic configuration of a hydraulic control device for a belt-type continuously variable transmission according to Embodiment 1 of the present invention, and FIG. -1 is a flowchart for explaining the gear ratio control of the belt type continuously variable transmission according to the first embodiment of the present invention, and FIG. 4-2 is the gear ratio 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 control.

  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, a primary partition wall, in addition to the primary shaft 51, the primary fixed sheave 52, the primary movable sheave 53, and the primary hydraulic chamber 54 described above. 56.

  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 on the primary shaft 51 in the axial direction and can 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 included 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. Between a normal state and a state in which 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 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 112 is continuous with the inner wall surface forming the second oil passage 102, and is tapered toward the inner side in the radial direction as it goes to the primary hydraulic chamber 54 side (first oil passage 86 side). 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 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 112 in the second oil passage 102 and can approach and separate from the valve seat 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 112, and the valve body 114, the valve seat 112, Is brought into a closed state by contact. 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 112, and the valve body 114 and the valve seat 112 are not in contact. The valve is opened by contact.

  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 has a piston 122, a drive hydraulic chamber 124, and a spring 126.

  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 112 side. Therefore, when the pressure receiving portion 122 a is pushed by the hydraulic pressure of the hydraulic oil in the drive hydraulic chamber 124, the piston 122 moves to the valve seat 112 side, and the valve body 114 moves to the valve seat 112 side together with the piston 122.

  The spring 126 is, for example, a coil spring, and is provided in the second oil passage 102 so as to contact the valve body 114. The spring 126 urges the valve body 114 toward the side away from the valve seat 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 to the valve seat 112 side 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, the pressure receiving portion 122a is moved to the valve seat 112 side by a certain distance, as shown in FIG. Block the opening. In other words, the hydraulic oil supply / discharge valve 110 moves in the direction in which the valve body 114 supplies hydraulic oil to the primary hydraulic chamber 54 in the second oil passage 102 and approaches the valve seat 112, so that the valve body 114, the valve seat 112, Contact with each other, the valve is closed, and the communication between the primary hydraulic chamber 54 and the hydraulic control device 130 is cut off. 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 oil pressure in the hydraulic drive chamber 124 is below a certain level, the valve body 114 is pushed away from the valve seat 112 by the spring 126 as shown in FIG. There is a space between the valve seat 112 and the opening. In other words, 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 and moves away from the valve seat 112, so that the valve body 114 and the valve seat 112 Is in a non-contact state, the valve is opened, and the primary hydraulic chamber 54 and the hydraulic control device 130 are in communication 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 changed by discharging the 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 an electromagnetic valve (not shown), for example, a linear solenoid valve, that 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 is, the line pressure PL, which is the input oil pressure, and sets the output oil pressure from the constant pressure control device 134 to a constant pressure. . 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. Therefore, the constant pressure 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. The primary hydraulic chamber controller 135 controls the supply flow rate of hydraulic oil supplied to the primary hydraulic chamber 54 and the discharge flow rate of hydraulic oil discharged from the primary hydraulic chamber 54. Furthermore, the primary hydraulic chamber control device 135 controls the primary hydraulic pressure Ps as the clamping pressure generating hydraulic chamber hydraulic pressure, which is the hydraulic pressure of the hydraulic oil in 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 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 through 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 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 introduced into the supply side control valve 135a is introduced into a control hydraulic chamber 135o described later of the supply side flow control valve 135c communicating with the first port 135k. In addition, the constant pressure 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 through 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 to an 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 passage R6. The second port 135i is connected to a later-described fourth port 135n of the supply-side flow rate control valve 135c via 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 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 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 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 to an 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. As described above, the first port 135r is connected to the second port 135i of the discharge-side control valve 135b. 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 arranged 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 has a degree of communication between the second port 135s and the third port 135t, that is, with respect to the second port 135s as the movement amount in one direction of the movement direction of the spool 135w increases. The channel cross-sectional area of the channel that communicates with the third port 135t increases. That is, the discharge-side flow rate control valve 135d has two ports, that is, a second port 135s and a 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. Communication and control the discharge flow rate.

  The drive hydraulic chamber controller 136 regulates the drive hydraulic pressure Pcv which is the hydraulic pressure of the drive hydraulic chamber 124. A constant pressure is introduced from the constant pressure control device 134 to the drive hydraulic chamber control device 136 as described above. 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 solenoid valve (solenoid valve of the present invention) 136a. The drive hydraulic chamber control device 136 is electrically connected to the ECU 140 and controls the solenoid valve 136a to be turned on / off by a control signal from the ECU 140. The solenoid valve 136a of the present embodiment is a so-called normally open type solenoid valve. In other words, the drive hydraulic chamber control device 136 is turned off, that is, when the solenoid valve 136a is turned off, the energized state is established, and when the solenoid valve 136a is opened, the branch oil passage R32 and the oil are The constant pressure introduced into the drive hydraulic chamber control device 136 is introduced into the drive hydraulic chamber 124, and the drive hydraulic pressure Pcv, which is the hydraulic pressure of the drive hydraulic chamber 124, is increased to a predetermined magnitude. Pressure. On the other hand, the drive hydraulic chamber control device 136 is turned on, that is, when the solenoid valve 136a is turned on, the energized state is established, and the solenoid valve 136a is closed so that the branch oil passage R32 and the oil passage The communication with R8 is blocked and the oil passage R8 is released to the outside, and the drive hydraulic pressure Pcv in the drive hydraulic chamber 124 is reduced to atmospheric pressure. That is, when the solenoid valve 136a is controlled to be OFF and is not energized, the drive hydraulic pressure Pcv becomes a constant pressure of a predetermined magnitude, and the drive hydraulic pressure Pcv for closing the hydraulic oil supply / discharge valve 110 is turned on. As a result of the ON control being performed, the drive hydraulic pressure Pcv becomes atmospheric pressure, and the ON state of the drive hydraulic pressure Pcv is released.

  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. doing. Furthermore, the secondary hydraulic chamber control device 137 controls the secondary hydraulic pressure Pd as the clamping pressure generating hydraulic chamber hydraulic pressure, which is the hydraulic pressure of the hydraulic oil in the secondary hydraulic chamber 64. 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 as a control means for controlling 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, an output rotation speed sensor 160, and a vehicle speed sensor 170.

  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. The input rotation speed sensor 150 is connected to the ECU 140 as shown in FIG. 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.

  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.

  The vehicle speed sensor 170 detects the speed of the vehicle 10 on which the belt type continuously variable transmission 22 is mounted, that is, the vehicle speed v. The vehicle speed sensor 170 is connected to the ECU 140 as shown in FIG. Therefore, the vehicle speed v detected by the vehicle speed sensor 170 is output to the ECU 140.

  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 actual 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. To 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 so that the operation state of the internal combustion engine 12 is optimal, and the current state of the primary hydraulic chamber 54 and the secondary hydraulic chamber 64 and the hydraulic control stored in the storage unit (not shown). From the relationship between the amount of hydraulic oil flowing between the device 130 and the primary hydraulic chamber 54 and the hydraulic pressure in the primary hydraulic chamber 54, the primary hydraulic chamber 54 in which the transmission ratio of the belt-type continuously variable transmission 22 becomes the target transmission ratio. The primary hydraulic pressure Ps as the clamping pressure generating hydraulic chamber hydraulic pressure, which is the hydraulic pressure of the hydraulic oil, and the secondary hydraulic pressure Pd as the clamping pressure generating hydraulic chamber hydraulic pressure, which is the hydraulic pressure of the hydraulic oil in 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, the gear ratio is changed, the ECU 140 reduces the drive hydraulic pressure Pcv of the drive hydraulic chamber 124 and opens the hydraulic oil supply / discharge valve 110.

  Specifically, the ECU 140 controls the solenoid valve 136a of the drive hydraulic chamber control device 136 to be ON. When the solenoid valve 136a of the drive hydraulic chamber control device 136 is ON-controlled by the ECU 140, the solenoid valve 136a is energized, the communication between the branch oil path R32 and the oil path R8 is interrupted, and the oil path R8 is Released to the outside, the drive hydraulic chamber 124 is released to atmospheric pressure, and the drive hydraulic pressure Pcv of the drive hydraulic chamber 124 is reduced to atmospheric pressure. Therefore, the valve body 114 of the hydraulic oil supply / discharge valve 110 is separated from the valve seat 112 by the urging 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 hydraulic pressure Ps of the primary hydraulic chamber 54 is regulated, so that the primary movable sheave 53 slides to a predetermined position in the axial direction of the primary shaft 51, and the primary fixed sheave 52 and the primary movable sheave 53 The interval between them, 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 Pd in the secondary hydraulic chamber 64 is regulated by controlling the secondary hydraulic chamber control device 137 by the ECU 140, and the belt 80 is moved by the secondary fixed sheave 62 and the secondary movable sheave 63. The belt clamping pressure to be clamped 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 primary hydraulic pressure Ps of the primary hydraulic chamber 54 rises due to the hydraulic oil supplied via the hydraulic oil supply / discharge valve 110 and the like, and the pressing force that presses the primary movable sheave 53 toward the primary fixed sheave side rises. The sheave 53 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 rate control valve 135d is adjusted to a predetermined pressure during 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 controlled in 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 at the time of 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 discharge flow rate of the hydraulic oil from the primary hydraulic chamber 54 becomes a discharge flow rate based on the increased 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, when the hydraulic oil is discharged from the primary hydraulic chamber 54 via the hydraulic oil supply / discharge valve 110, the primary hydraulic pressure Ps of the primary hydraulic chamber 54 is reduced, and the primary movable sheave 53 is pushed toward the primary fixed sheave side. The pressure decreases, and the primary movable sheave 53 slides in the axial direction on the side opposite to the primary fixed sheave side. 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, when there is no need to change the gear ratio significantly, such as when the traveling state of the vehicle 10 is stable, the ECU 140 controls the gear ratio to be fixed, that is, the gear ratio to be steady. 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 speed ratio is fixed, the drive hydraulic pressure Pcv of 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. Further, the discharge of hydraulic oil from the primary hydraulic chamber 54 via the hydraulic oil supply / discharge valve 110 is prohibited.

  Specifically, the ECU 140 controls the solenoid valve 136a of the drive hydraulic chamber control device 136 to be OFF. When the solenoid valve 136a of the drive hydraulic chamber control device 136 is OFF-controlled by the ECU 140, the solenoid valve 136a is deenergized, the branch oil passage R32 and the oil passage R8 communicate with each other, and the drive hydraulic chamber control device 136 is connected. The constant pressure introduced to the drive hydraulic chamber 124 is introduced into the drive hydraulic chamber 124, and the drive hydraulic pressure Pcv of the drive hydraulic chamber 124 is increased to a predetermined pressure. Therefore, the valve body 114 of the hydraulic oil supply / discharge valve 110 comes into contact with the valve seat 112 by the drive hydraulic pressure Pcv of the hydraulic oil in the drive hydraulic chamber 124 at a predetermined constant pressure, 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 confined and held. 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 supply / discharge valve 110 is closed, the hydraulic oil is confined and held in the primary hydraulic chamber 54. Therefore, the primary fixed sheave of the primary movable sheave 53 is fixed. Even if the position in the axial direction with respect to 52 changes, the primary hydraulic pressure Ps of the primary hydraulic chamber 54 also changes in accordance with the belt reaction force acting from the belt 80 via the primary movable sheave 53, so that the primary of the primary movable sheave 53 is changed. The position in the axial direction with respect to the fixed sheave 52 is kept 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, the primary hydraulic pressure Ps of the primary hydraulic chamber 54 is not increased by supplying hydraulic oil to the primary hydraulic chamber 54. Also good. Thereby, when the transmission gear ratio is fixed in the valve-closed state, it is not necessary to drive the oil pump 132 in order to supply the hydraulic oil to the primary hydraulic chamber 54. Therefore, it is possible to suppress an increase in driving loss of the oil pump 132. it can.

  Incidentally, in the belt type continuously variable transmission 22 as described above, as shown in FIG. 2B, the valve body 114 in the closed state of the hydraulic oil supply / discharge valve 110 has a spring opening direction pressing force Fsp, The driving hydraulic valve closing direction pressing force Fpcv and the primary hydraulic valve opening direction pressing force Fps act. The spring opening direction pressing force Fsp is a pressing force in the valve opening direction corresponding to the urging force of the spring 126, and acts on the valve body 114. The driving hydraulic valve closing direction pressing force Fpcv is a pressing force in the valve closing direction corresponding to the driving hydraulic pressure Pcv of the hydraulic oil in the driving hydraulic chamber 124, and acts on the valve body 114 via the piston 122. The primary hydraulic valve opening direction pressing force Fps is a pressing force in the valve opening direction according to the primary hydraulic pressure Ps as the clamping pressure generating hydraulic chamber hydraulic pressure that is the hydraulic pressure of the hydraulic oil in the primary hydraulic chamber 54, and the second oil passage 102. , The valve body 114 acts on the valve body 114 via the hydraulic oil on the primary hydraulic chamber 54 side.

The hydraulic oil supply / discharge valve 110 has a relationship between the three pressing forces, that is, the spring opening direction pressing force Fsp, the driving hydraulic valve closing direction pressing force Fpcv, and the primary hydraulic valve opening direction pressing force Fps as follows. When the relational expression (1) is satisfied, the valve body 114 and the valve seat 112 come into contact with each other and the valve is closed. In other words, in the hydraulic oil supply / discharge valve 110, the relationship among the spring opening direction pressing force Fsp, the driving hydraulic valve closing direction pressing force Fpcv, and the primary hydraulic valve opening direction pressing force Fps is expressed by the following relational expression (2 ), The valve body 114 and the valve seat 112 are separated from each other and the valve is opened.

Fpcv> Fsp + Fps (1)

Fpcv <Fsp + Fps (2)

  Here, if an electrical failure (such as a short circuit) occurs in the solenoid valve 136a of the drive hydraulic chamber control device 136, the solenoid valve 136a is a normally open solenoid valve as described above. Even if the solenoid valve 136a is ON-controlled, the energized state continues without being energized, and the solenoid valve 136a continues to open so that the branch oil path R32 and the oil path R8 maintain communication and are driven. There is a possibility that the constant pressure continues to be introduced into the hydraulic chamber 124 and the drive hydraulic pressure Pcv of the drive hydraulic chamber 124 remains at a constant pressure of a predetermined magnitude. In this case, the belt type continuously variable transmission 22 continues to introduce a constant pressure into the drive hydraulic chamber 124 even though the solenoid valve 136a is ON-controlled, and the drive hydraulic pressure Pcv of the drive hydraulic chamber 124 is predetermined. Is maintained at a constant pressure of the magnitude of the hydraulic pressure, and the valve body 114 of the hydraulic oil supply / discharge valve 110 is maintained in contact with the valve seat 112 by the driving hydraulic pressure Pcv of the hydraulic oil in the driving hydraulic chamber 124. The oil supply / discharge valve 110 is maintained in the closed state, and as a result, the gear ratio may remain fixed.

  Therefore, in the belt type continuously variable transmission 22 of the present embodiment, the ECU 140 as the control means controls the hydraulic control device 130 when the solenoid valve 136a of the drive hydraulic chamber control device 136 fails, and the secondary hydraulic pressure in the secondary hydraulic chamber 64 is controlled. By increasing the pressure of Pd and controlling the gear ratio, the gear ratio is properly controlled even when the solenoid valve 136a fails.

  As described above, in the closed state of the hydraulic oil supply / discharge valve 110, the relationship among the spring valve opening direction pressing force Fsp, the drive hydraulic valve closing direction pressing force Fpcv, and the primary hydraulic valve opening direction pressing force Fps is: The relational expression (1) is satisfied. At this time, the spring opening direction pressing force Fsp when the valve body 114 is in the valve closing position does not vary and is always constant. Further, the driving hydraulic valve closing direction pressing force Fpcv at the time of failure of the solenoid valve 136a is the driving hydraulic pressure Pcv of the driving hydraulic chamber 124 when the solenoid valve 136a is continuously de-energized and the solenoid valve 136a is continuously opened. Since it remains at a constant pressure of a predetermined magnitude, it is always constant without fluctuation. For this reason, in the hydraulic oil supply / discharge valve 110, the primary hydraulic pressure Ps of the primary hydraulic chamber 54 is adjusted, the spring opening direction pressing force Fsp, the driving hydraulic valve closing direction pressing force Fpcv, and the primary hydraulic valve opening direction pressing force Fps. If the relationship between the valve body 114 and the valve seat 112 is separated, the valve body 114 and the valve seat 112 are opened.

  Therefore, the ECU 140 controls the secondary hydraulic chamber control device 137 of the hydraulic control device 130 to increase the secondary hydraulic pressure Pd of the secondary hydraulic chamber 64 when the solenoid valve 136a of the drive hydraulic chamber control device 136 fails. In the closed state of the hydraulic oil supply / discharge valve 110, the hydraulic oil is confined and held in the primary hydraulic chamber 54, so that when the belt tension of the belt 80 changes, the belt 80 passes through the primary movable sheave 53. The primary hydraulic pressure Ps of the primary hydraulic chamber 54 also changes in accordance with the acting belt reaction force, and as a result, the primary hydraulic valve opening direction pressing force Fps also changes accordingly. That is, when the secondary hydraulic pressure Pd is increased to a predetermined pressure in the closed state of the hydraulic oil supply / discharge valve 110, the belt tension of the belt 80 increases according to the thrust by the secondary hydraulic pressure Pd, and the primary movable sheave from the belt 80 increases. The primary hydraulic pressure Ps of the primary hydraulic chamber 54 is increased according to the belt reaction force acting via 53, and as a result, the primary hydraulic valve opening direction pressing force Fps also increases accordingly. Here, the thrust by the secondary hydraulic pressure Pd corresponds to a belt clamping pressure that clamps the belt 80 generated between the secondary fixed sheave 62 and the secondary movable sheave 63 by the secondary hydraulic pressure Pd.

  In the belt type continuously variable transmission 22, when the secondary hydraulic pressure Pd is increased to a predetermined pressure, the primary hydraulic pressure Ps is also increased to a predetermined pressure, and the primary hydraulic valve opening direction pressing force Fps is increased to a predetermined magnitude, The relationship between the spring valve opening direction pressing force Fsp, the drive hydraulic valve closing direction pressing force Fpcv, and the primary hydraulic valve opening direction pressing force Fps satisfies the relational expression (2). The valve body 114 and the valve seat 112 are separated from each other and the valve is opened. As a result, since the hydraulic oil supply / discharge valve 110 is opened, the belt type continuously variable transmission 22 supplies hydraulic oil from the hydraulic control device 130 to the primary hydraulic chamber 54 or hydraulic pressure from the primary hydraulic chamber 54. The hydraulic oil can be discharged to the outside of the primary pulley 50 via the control device 130, and an appropriate gear ratio can be controlled by controlling the hydraulic control device 130 by the ECU 140.

  Next, the speed ratio control at the time of failure of the solenoid valve 136a of the belt type continuously variable transmission 22 will be described with reference to the flowchart of FIG. In FIG. 4B, the vertical axis indicates ON / OFF of the opening instruction of the hydraulic oil supply / discharge valve 110, the gear ratio γ, the drive hydraulic pressure Pcv, the supply hydraulic pressure Pin, the secondary hydraulic pressure Pd, and the vehicle speed v, and the horizontal axis indicates the time axis. Yes. This control routine is repeatedly executed at a control cycle of several ms to several tens of ms. Here, the supply hydraulic pressure Pin is the supply pressure of the hydraulic oil supplied to the primary hydraulic chamber 54. When the hydraulic oil supply / discharge valve 110 is in the open state, the hydraulic oil supply / discharge valve 110 in the supply / discharge path This is the hydraulic pressure of the upstream hydraulic oil that is the hydraulic oil upstream of the body 114 (opposite to the primary hydraulic chamber 54 side across the valve body 114).

  First, the ECU 140 turns on a valve opening instruction of the hydraulic oil supply / discharge valve 110, controls the solenoid valve 136a of the drive hydraulic chamber control device 136 to be ON, and executes gear ratio transition, that is, gear ratio change control ( S100, for example, time t11 in FIG.

  Next, the ECU 140 determines whether or not the speed ratio has changed, that is, whether or not the speed ratio has been changed (S101, for example, time t12 in FIG. 4B). The ECU 140 may determine whether or not the gear ratio γ has changed based on various known methods, for example, according to detection signals from the input rotation speed sensor 150 and the output rotation speed sensor 160.

  If the ECU 140 determines that the gear ratio has changed (S101: No), the ECU 140 ends the gear ratio control at the time of failure of the solenoid valve 136a.

  If the ECU 140 determines that the gear ratio has not changed (S101: Yes), the ECU 140 determines that the opening operation of the hydraulic oil supply / discharge valve 110 has failed, and determines whether or not the drive hydraulic pressure Pcv cannot be released. In spite of the solenoid valve 136a of the drive hydraulic chamber control device 136 being ON-controlled, the drive oil pressure Pcv of a predetermined pressure is continuously applied and an electrical failure occurs in the solenoid valve 136a. (S102, for example, time t13 in FIG. 4B). The ECU 140 determines whether or not the drive hydraulic pressure Pcv can be released even though the solenoid valve 136a is ON-controlled based on various known methods according to various control signals input and output by the ECU 140, for example. It may be determined whether or not an electrical failure has occurred in the solenoid valve 136a.

  If the ECU 140 determines that the ON of the drive hydraulic pressure Pcv can be released by controlling the solenoid valve 136a to be ON (S102: No), the ECU 140 ends the gear ratio control at the time of failure of the solenoid valve 136a.

  If the ECU 140 determines that the drive hydraulic pressure Pcv cannot be released even though the solenoid valve 136a is ON controlled (S102: Yes), the ECU 140 controls the secondary hydraulic chamber control device 137 of the hydraulic control device 130 to control the secondary hydraulic chamber. The secondary hydraulic pressure Pd of 64 is increased (S103, for example, time t14 in FIG. 4-2).

  Next, the ECU 140 determines whether or not the gear ratio has changed (S104, for example, time t15 in FIG. 4-2).

  When ECU 140 determines that the gear ratio has not changed (S104: No), ECU 140 ends the gear ratio control at the time of failure of solenoid valve 136a.

  When it is determined that the gear ratio has changed (S104: Yes), the ECU 140 determines whether or not the gear ratio has reached the maximum reduction ratio, that is, the maximum gear ratio γmax (S105).

  If the ECU 140 determines that the speed ratio is not the maximum reduction ratio (maximum speed ratio γmax) (S105: No), the ECU 140 returns to S104 and repeats the subsequent processing.

  When the ECU 140 determines that the speed ratio has reached the maximum reduction ratio (maximum speed ratio γmax) (S105: Yes, for example, time t16 in FIG. 4B), the speed ratio control at the time of failure of the solenoid valve 136a is terminated. .

  In the belt type continuously variable transmission 22 of the present embodiment, the supply hydraulic pressure Pin is constant during this period (for example, from time t11 to time t16). Further, the vehicle speed v is gradually decreased at time t15 as the hydraulic oil supply / discharge valve 110 is opened and hydraulic oil is discharged from the primary hydraulic chamber 54 and downshifted, that is, the gear ratio is increased. doing.

  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 mounted on the vehicle 10, and the primary pulley 50 and the secondary pulley 60 are provided. A primary hydraulic chamber 54 and a secondary hydraulic pressure that are wound around each of the belt 80, which transmits the driving force from the internal combustion engine 12, and the primary pulley 50 and the secondary pulley 60, and generates a belt clamping pressure against the belt 80 by hydraulic pressure. The first oil passage 86 and the second oil passage 102 as supply and discharge passages for supplying hydraulic oil to the chamber 64 and the primary hydraulic chamber 54 as one clamping pressure generating hydraulic chamber and discharging the hydraulic oil from the primary hydraulic chamber 54. And the valve body 114 provided in the second oil passage 102 as the supply / discharge route is the primary hydraulic chamber 54. The piston 122 is moved by the hydraulic oil supply / discharge valve 110 which can be opened by moving in the direction of discharging the hydraulic oil and moving away from the valve seat 112, and the drive hydraulic pressure Pcv which is the hydraulic pressure of the hydraulic oil in the drive hydraulic chamber 124. Thus, the actuator 120 capable of closing the hydraulic oil supply / discharge valve 110 by moving the valve body 114 in the direction of supplying hydraulic oil to the primary hydraulic chamber 54 and contacting the valve seat 112, the primary hydraulic chamber 54, and the secondary hydraulic chamber The primary hydraulic pressure Ps and the secondary hydraulic pressure Pd, which are hydraulic pressures of 64 hydraulic oils, can be controlled, and the drive hydraulic pressure Pcv is controlled via the solenoid valve 136a to increase the drive hydraulic pressure Pcv by deenergizing the solenoid valve 136a. Then, the actuator 120 closes the hydraulic oil supply / discharge valve 110 to fix the gear ratio, while the solenoid valve 13 The hydraulic oil supply / discharge valve 110 is opened by depressing the drive hydraulic pressure Pcv with the a being energized to supply the hydraulic oil to the primary hydraulic chamber 54, or the hydraulic oil is discharged from the primary hydraulic chamber 54 to change the gear ratio. The hydraulic pressure control device 130 and an ECU 140 that controls the hydraulic pressure control device 130 to increase the secondary hydraulic pressure Pd in the secondary hydraulic pressure chamber 64 and control the gear ratio when the solenoid valve 136a fails.

  Therefore, in the belt-type continuously variable transmission 22, the ECU 140 controls the hydraulic control device 130 to increase the secondary hydraulic pressure Pd in the secondary hydraulic chamber 64 and control the gear ratio when the solenoid valve 136a fails, so that the solenoid valve 136a is controlled. Even if the solenoid valve 136a is not energized and the drive hydraulic pressure Pcv cannot be reduced despite the ON control of the secondary pressure Pd, the belt tension is increased by increasing the secondary hydraulic pressure Pd to a predetermined pressure. Since the belt reaction force acting on the hydraulic oil in the primary hydraulic chamber 54 increases and the primary hydraulic pressure Ps increases, the hydraulic oil supply / discharge valve 110 can be opened to change the gear ratio, and the solenoid valve 136a fails. Even at times, the gear ratio can be controlled appropriately. As a result, the belt-type continuously variable transmission 22 can prevent the gear ratio from being fixed at the high side (minimum gear ratio side), for example, when the solenoid valve 136a fails, and thus the gear ratio cannot be fixed. For example, it is possible to prevent the backlash at the time of acceleration and the engine stall at the time of restart, and to improve the reliability.

(Embodiment 2)
FIG. 5-1 is a flowchart for explaining speed ratio control of the belt-type continuously variable transmission according to the second embodiment of the present invention, and FIG. 5-2 is a diagram of the belt-type continuously variable transmission according to the second embodiment of the present invention. FIG. 6 is a time chart for explaining an example of the gear ratio control, and FIG. 6 is a gear ratio map of the belt type continuously variable transmission according to the second embodiment of the present invention. 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 the gear ratio is changed stepwise according to the vehicle speed when the solenoid valve fails. It differs from the belt type continuously variable transmission according to the first embodiment in that it is changed. 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.

  The ECU 140 of the belt type continuously variable transmission 222 according to the present embodiment controls the hydraulic control device 130 and changes the gear ratio stepwise according to the speed of the vehicle 10 when the solenoid valve 136a fails. The ECU 140 acquires the vehicle speed v detected by the vehicle speed sensor 170, sets a target gear ratio according to the vehicle speed v, and sets the hydraulic control device 130 so that the actual gear ratio becomes the target gear ratio. Control. At this time, the ECU 140 changes and sets the target gear ratio stepwise in accordance with the vehicle speed v. Furthermore, the ECU 140 increases the target gear ratio stepwise in accordance with the deceleration of the vehicle speed v.

  As a result, the belt-type continuously variable transmission 222 changes the gear ratio in a stepwise manner according to the vehicle speed v when the solenoid valve 136a fails, thus preventing a sudden shift (deceleration) from occurring when a failure occurs. Therefore, it is possible to shift (decelerate) safely and to act as a fail safe, thereby improving reliability. The belt type continuously variable transmission 222 does not need to continuously maintain the secondary hydraulic pressure Pd at a relatively high hydraulic pressure when the solenoid valve 136a fails. Since the state in which the pinching pressure is relatively high is suppressed from continuing for a long time, it is possible to suppress the life of the belt 80 from being shortened, and as a result, it is possible to improve durability.

  Next, the speed ratio control at the time of failure of the solenoid valve 136a of the belt type continuously variable transmission 222 will be described with reference to the flowchart of FIG. This control routine is repeatedly executed at a control cycle of several ms to several tens of ms.

  First, the ECU 140 turns on a valve opening instruction of the hydraulic oil supply / discharge valve 110, controls the solenoid valve 136a of the drive hydraulic chamber control device 136 to be ON, and executes gear ratio transition, that is, gear ratio change control ( S200, for example, time t21 in FIG.

  Next, the ECU 140 determines whether or not the gear ratio has changed, that is, whether or not the gear ratio has been changed (S201, for example, time t22 in FIG. 5-2).

  If the ECU 140 determines that the gear ratio has transitioned (S201: No), the gear ratio control at the time of failure of the solenoid valve 136a is terminated.

  If the ECU 140 determines that the gear ratio has not changed (S201: Yes), the ECU 140 determines that the opening operation of the hydraulic oil supply / discharge valve 110 has failed, and whether or not the drive hydraulic pressure Pcv cannot be turned on, that is, In spite of the solenoid valve 136a of the drive hydraulic chamber control device 136 being ON-controlled, the drive oil pressure Pcv of a predetermined pressure is continuously applied and an electrical failure occurs in the solenoid valve 136a. (S202, for example, time t23 in FIG. 5-2).

  If the ECU 140 determines that the ON of the drive hydraulic pressure Pcv can be released by controlling the solenoid valve 136a to be ON (S202: No), the ECU 140 ends the gear ratio control at the time of failure of the solenoid valve 136a.

  If the ECU 140 determines that the drive hydraulic pressure Pcv cannot be released even though the solenoid valve 136a is turned on (S202: Yes), the ECU 140 reads the current vehicle speed v detected by the vehicle speed sensor 170, and based on the vehicle speed v. The target gear ratio γ is set (S203), the secondary hydraulic chamber control device 137 of the hydraulic control device 130 is controlled to increase the secondary hydraulic pressure Pd of the secondary hydraulic chamber 64 (S204, for example, time t24- in FIG. 5-2). 1, t24-2, t24-3).

  Here, the ECU 140 determines the target speed ratio γ based on, for example, the speed ratio map shown in FIG. This gear ratio map describes the relationship between the vehicle speed v and the target gear ratio γ. In this gear ratio map, each target gear ratio γ is set to a gear ratio at which the deceleration acceleration α due to the downshift with respect to the vehicle speed v does not exceed a preset allowable deceleration acceleration. The allowable deceleration acceleration may be set to a value that can sufficiently ensure the stability and controllability of the vehicle 10, for example. The gear ratio map is stored in the storage unit of the ECU 140. The ECU 140 obtains the target speed ratio γ from the vehicle speed v based on the speed ratio map. In the present embodiment, the ECU 140 calculates the target gear ratio γ corresponding to the vehicle speed v using the gear ratio map, but the present embodiment is not limited to this. The ECU 140 may obtain the target speed ratio γ corresponding to the vehicle speed v based on, for example, a mathematical formula corresponding to the speed ratio map.

  Next, the ECU 140 executes gear ratio transition, that is, gear ratio change control based on the target gear ratio γ set in S203 (S205).

  Next, the ECU 140 determines whether or not the actual gear ratio has converged to the target gear ratio γ set in S203 (S206).

  When it is determined that the actual gear ratio has not converged to the target gear ratio γ set in S203 (S206: No), the ECU 140 returns to S205 and repeats the subsequent processing.

  When it is determined that the actual gear ratio has converged to the target gear ratio γ set in S203 (S206: Yes), the ECU 140 controls the secondary hydraulic chamber control device 137 of the hydraulic control device 130 to control the secondary hydraulic chamber 64. The pressure increase of the secondary hydraulic pressure Pd is released (S207, for example, times t25-1, t25-2, and t25-3 in FIG. 5-2).

  Next, the ECU 140 determines whether or not the speed ratio has reached the maximum reduction ratio, that is, the maximum speed ratio γmax (S208).

  If the ECU 140 determines that the speed ratio is not the maximum reduction ratio (maximum speed ratio γmax) (S208: No), the ECU 140 returns to S203 and repeats the subsequent processing.

  When ECU 140 determines that the speed ratio has reached the maximum reduction ratio (maximum speed ratio γmax) (S208: Yes, eg, time t26 in FIG. 5-2), the speed ratio control at the time of failure of solenoid valve 136a is terminated. .

  In the belt type continuously variable transmission 222 of the present embodiment, the supply hydraulic pressure Pin is constant during this period (from time t21 to time t26). Further, the speed ratio γ increases stepwise from time t24-1 to time t25-1, from time t24-2 to time t25-2, and from time t24-3 to time t25-3. The vehicle speed v decreases gradually from time t24-1 to time t25-1, from time t24-2 to time t25-2, and from time t24-3 to time t25-3, and gradually decreases.

  According to the belt-type continuously variable transmission 222 according to the embodiment of the present invention described above, the belt-type continuously variable transmission 222 controls the hydraulic control device 130 and the secondary hydraulic chamber when the ECU 140 fails in the solenoid valve 136a. Even if the solenoid valve 136a is not energized and the drive oil pressure Pcv cannot be reduced, the 64 secondary oil pressure Pd is increased and the gear ratio is controlled. Since the secondary hydraulic pressure Pd is increased to a predetermined pressure, the belt tension increases, the belt reaction force acting on the hydraulic oil in the primary hydraulic chamber 54 increases, and the primary hydraulic pressure Ps increases, so the hydraulic oil supply / discharge valve 110 can be opened to change the gear ratio, and the gear ratio can be controlled properly even when the solenoid valve 136a fails. It can be.

  Furthermore, according to the belt-type continuously variable transmission 222 according to the embodiment of the present invention described above, the ECU 140 controls the hydraulic control device 130 in a stepwise manner according to the speed of the vehicle 10 when the solenoid valve 136a fails. Change the gear ratio to. Therefore, the belt-type continuously variable transmission 222 controls the hydraulic control device 130 when the solenoid valve 136a fails, and changes the gear ratio stepwise according to the vehicle speed v. Can be prevented, the reliability can be improved, and the secondary oil pressure Pd does not need to be maintained at a relatively high oil pressure continuously. Can be suppressed, and as a result, durability can be improved.

(Embodiment 3)
FIG. 7-1 is a flowchart for explaining the gear ratio control of the belt-type continuously variable transmission according to the third embodiment of the present invention, and FIG. 7-2 is the flowchart of the belt-type continuously variable transmission according to the third embodiment of the present invention. It is a time chart explaining an example of gear ratio control. The belt-type continuously variable transmission according to the third embodiment has substantially the same configuration as the belt-type continuously variable transmission according to the first embodiment, but the supply hydraulic pressure is equal to the clamping pressure generating hydraulic chamber hydraulic pressure when the solenoid valve fails. It differs from the belt type continuously variable transmission according to the first embodiment in that it is set. 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.

  The ECU 140 of the belt-type continuously variable transmission 322 according to the present embodiment controls the hydraulic control device 130 during the failure of the solenoid valve 136a and supplies hydraulic oil supplied to the primary hydraulic chamber 54 serving as one clamping pressure generating hydraulic chamber. The supply hydraulic pressure Pin that is the hydraulic pressure is set to be equal to the primary hydraulic pressure Ps of the primary hydraulic chamber 54. Here, as described above, the supply hydraulic pressure Pin is the supply pressure of the hydraulic oil supplied to the primary hydraulic chamber 54. When the hydraulic oil supply / discharge valve 110 is in the open state, the hydraulic oil supply in the supply / discharge path is performed. This is the hydraulic pressure of the upstream side hydraulic oil that is upstream of the valve body 114 of the discharge valve 110 (the side opposite to the primary hydraulic chamber 54 side with the valve body 114 interposed). That is, when the solenoid valve 136a fails, the ECU 140 controls the hydraulic control device 130 to increase the supplied hydraulic pressure Pin until it becomes equal to the primary hydraulic pressure Ps of the primary hydraulic chamber 54, so that the primary hydraulic pressure Ps of the primary hydraulic chamber 54 is increased. And the pressure difference between the supply oil pressure Pin and the supply oil pressure Pin.

  As a result, the belt-type continuously variable transmission 322 controls the supply hydraulic pressure Pin so that the pressure difference between the primary hydraulic pressure Ps of the primary hydraulic chamber 54 and the supply hydraulic pressure Pin becomes small when the solenoid valve 136a fails. The pressure difference between the upstream side and the downstream side of the valve body 114 of the hydraulic oil supply / discharge valve 110 in the supply / discharge path, here, the second oil path 102 becomes smaller. For this reason, the belt-type continuously variable transmission 322 is configured such that the supply hydraulic pressure Pin is set to be equal to the primary hydraulic pressure Ps so that the pressure difference between the upstream side and the downstream side of the valve body 114 becomes smaller. When the failure of the solenoid valve 136a occurs intermittently, that is, when the solenoid valve 136a is ON-controlled, the solenoid valve 136a is intermittently repeatedly switched between the energized state and the non-energized state. Can be prevented from suddenly depressurizing when the engine is intermittently repeated. Therefore, the belt-type continuously variable transmission 322 reliably prevents the primary hydraulic pressure Ps from being suddenly reduced during the failure of the solenoid valve 136a. Since it is possible to prevent slippage in 80, reliability and durability can be improved. Further, the belt-type continuously variable transmission 322 reliably prevents the primary hydraulic pressure Ps from being suddenly reduced during the failure of the solenoid valve 136a, so that a discontinuous deceleration behavior appears in the vehicle 10. Since it can prevent, and it can prevent that steering stability falls, reliability and safety | security can be improved also in this point.

  Next, speed ratio control at the time of failure of the solenoid valve 136a of the belt type continuously variable transmission 322 will be described with reference to a flowchart of FIG. 7-1 and a time chart of FIG. 7-2. This control routine is repeatedly executed at a control cycle of several ms to several tens of ms.

  First, the ECU 140 turns on a valve opening instruction of the hydraulic oil supply / discharge valve 110, controls the solenoid valve 136a of the drive hydraulic chamber control device 136 to be ON, and executes gear ratio transition, that is, gear ratio change control ( S300, for example, time t31 in FIG.

  Next, the ECU 140 determines whether or not the gear ratio has changed, that is, whether or not the gear ratio has been changed (S301, for example, time t32 in FIG. 7-2).

  When the ECU 140 determines that the gear ratio has transitioned (S301: No), the ECU 140 ends the gear ratio control at the time of failure of the solenoid valve 136a.

  When the ECU 140 determines that the gear ratio has not changed (S301: Yes), the ECU 140 determines that the opening operation of the hydraulic oil supply / discharge valve 110 has failed, and whether or not the drive hydraulic pressure Pcv cannot be turned on, that is, In spite of the solenoid valve 136a of the drive hydraulic chamber control device 136 being ON-controlled, the drive oil pressure Pcv of a predetermined pressure is continuously applied and an electrical failure occurs in the solenoid valve 136a. (S302, for example, time t33 in FIG. 7-2).

  When the ECU 140 determines that the drive hydraulic pressure Pcv can be turned off by controlling the solenoid valve 136a to be ON (S302: No), the ECU 140 ends the gear ratio control at the time of failure of the solenoid valve 136a.

  If the ECU 140 determines that the drive hydraulic pressure Pcv cannot be released even though the solenoid valve 136a is ON controlled (S302: Yes), the ECU 140 controls the hydraulic control device 130 to supply the supplied hydraulic pressure Pin supplied to the primary hydraulic chamber 54. Is set equal to the primary hydraulic pressure Ps of the primary hydraulic chamber 54 (S303, for example, time t34 in FIG. 7-2). Here, the ECU 140 is based on, for example, the engine torque (output torque) Te generated by the internal combustion engine 12, the input rotational speed Nin detected by the input rotational speed sensor 150, the secondary hydraulic pressure Pd of the secondary hydraulic chamber 64, the gear ratio γ, and the like. Thus, the primary hydraulic pressure Ps confined in the primary hydraulic chamber 54 may be estimated and calculated by various known methods.

  Next, the ECU 140 controls the secondary hydraulic chamber control device 137 of the hydraulic control device 130 to increase the secondary hydraulic pressure Pd of the secondary hydraulic chamber 64 (S304, for example, time t35 in FIG. 7-2).

  Next, the ECU 140 determines whether or not the gear ratio has changed (S305, for example, time t36 in FIG. 7-2).

  When ECU 140 determines that the gear ratio has not changed (S305: No), ECU 140 ends the gear ratio control at the time of failure of solenoid valve 136a.

  When it is determined that the gear ratio has changed (S305: Yes), the ECU 140 determines whether or not the gear ratio has reached the maximum reduction ratio, that is, the maximum gear ratio γmax (S306).

  When ECU 140 determines that the speed ratio is not the maximum speed reduction ratio (maximum speed ratio γmax) (S306: No), it returns to S305 and repeats the subsequent processing.

  When the ECU 140 determines that the speed ratio has reached the maximum speed reduction ratio (maximum speed ratio γmax) (S306: Yes, for example, time t37 in FIG. 7-2), the speed ratio control at the time of failure of the solenoid valve 136a is terminated. .

  According to the belt-type continuously variable transmission 322 according to the embodiment of the present invention described above, the belt-type continuously variable transmission 322 controls the hydraulic control device 130 when the ECU 140 fails in the solenoid valve 136a, and the secondary hydraulic chamber. Even if the solenoid valve 136a is not energized and the drive oil pressure Pcv cannot be reduced, the 64 secondary oil pressure Pd is increased and the gear ratio is controlled. Since the secondary hydraulic pressure Pd is increased to a predetermined pressure, the belt tension increases, the belt reaction force acting on the hydraulic oil in the primary hydraulic chamber 54 increases, and the primary hydraulic pressure Ps increases, so the hydraulic oil supply / discharge valve 110 can be opened to change the gear ratio, and the gear ratio can be controlled properly even when the solenoid valve 136a fails. It can be.

  Furthermore, according to the belt-type continuously variable transmission 322 according to the embodiment of the present invention described above, the ECU 140 controls the hydraulic control device 130 during the failure of the solenoid valve 136a and serves as one clamping pressure generating hydraulic chamber. The supply hydraulic pressure Pin that is the hydraulic pressure of the hydraulic oil supplied to the primary hydraulic chamber 54 is set to be equal to the primary hydraulic pressure Ps of the primary hydraulic chamber 54. Therefore, in the belt type continuously variable transmission 322, when the solenoid valve 136a fails, the ECU 140 controls the supply hydraulic pressure Pin so that the pressure difference between the primary hydraulic pressure Ps of the primary hydraulic chamber 54 and the supply hydraulic pressure Pin becomes small. Since it is possible to reliably prevent the primary hydraulic pressure Ps from being suddenly reduced, it is possible to prevent sudden shifts due to sudden pressure reduction and slippage of the belt 80. It is possible to prevent a discontinuous deceleration behavior from appearing in the vehicle 10 and to prevent a decrease in steering stability. As a result, the belt type continuously variable transmission 322 can improve reliability, durability, and safety.

  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. The belt type continuously variable transmission according to the embodiment of the present invention may be configured by combining a plurality of the embodiments described above.

  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.

  FIG. 8 is a conceptual diagram showing a belt type continuously variable transmission according to Embodiment 2 of the present invention. In the figure, the same components as those of the belt-type continuously variable transmission 22 of the first embodiment are denoted by the same reference numerals, and the description thereof is omitted. In the second embodiment, the configuration on the primary pulley 50 side will be described as an example, but the same configuration may be applied to the secondary pulley 60 side (not shown).

  As described above, in the belt type continuously variable transmission 22, the hydraulic pressure control of the hydraulic oil of the primary pulley 50 is performed, whereby the clamping pressure of the belt 80 is adjusted and the gear ratio control is performed (see FIG. 8). . Specifically, the primary pulley 50 has a primary hydraulic chamber 54 for confining the hydraulic oil, and the hydraulic control device 130 (see FIG. 3) controls the hydraulic oil pressure (primary hydraulic pressure Ps) of the primary hydraulic chamber 54. To do. Thereby, the movable sheave 53 of the primary pulley 50 is driven and controlled, the groove width of the primary groove 80a is adjusted, and the clamping pressure of the belt 80 changes (fluid confinement type sheave positioning mechanism).

  A hydraulic oil supply / discharge valve 110 is disposed on the hydraulic oil passage (second oil passage 102) from the hydraulic control device 130 to the primary hydraulic chamber 54. The hydraulic oil supply / discharge valve 110 is a check valve including a valve body 114 and a valve seat 112, and the communication between the hydraulic control device 130 and the primary hydraulic chamber 54 is turned ON / OFF by an opening / closing operation thereof. The opening / closing operation of the hydraulic oil supply / discharge valve 110 is performed by the switching mechanism 100. The switching mechanism 100 includes an actuator 120 including a piston 122 and a spring 126, and displaces the valve body 114 of the hydraulic oil supply / discharge valve 110 by the pressing force (driving oil pressure Pcv) of the piston 122 and the repulsive force Fsp of the spring 126. Then, the hydraulic oil supply / discharge valve 110 is opened / closed.

  In the belt-type continuously variable transmission 22, the hydraulic oil supply / discharge valve 110 of the switching mechanism 100 is in a closed state when the gear ratio is not changed (see FIG. 2-2). Then, the hydraulic oil is confined in the primary hydraulic chamber 54, and the primary hydraulic pressure Ps becomes constant. As a result, the movable sheave 53 is fixed and the gear ratio is constant.

  On the other hand, the hydraulic oil supply / discharge valve 110 is normally opened at the time of shifting of the gear ratio (see FIG. 2-1). Specifically, when the opening instruction of the hydraulic oil supply / discharge valve 110 is set to ON, the drive hydraulic pressure Pcv of the actuator 120 is turned OFF, and the valve body 114 is repelled by the primary hydraulic pressure Ps of hydraulic oil and the spring 126. The hydraulic oil supply and discharge valve 110 is opened by being pushed away from the valve seat 112 by Fsp. At this time, the hydraulic control device 130 supplies hydraulic oil of the supply hydraulic pressure Pin corresponding to the gear ratio to the second oil passage 102. Then, the hydraulic oil of this supply hydraulic pressure Pin is supplied to the primary hydraulic chamber 54, and the primary hydraulic pressure Ps changes. As a result, the movable sheave 53 is driven, the clamping pressure of the belt 80 changes, and the gear ratio changes.

  Here, as described above, the hydraulic oil supply / discharge valve 110 is set to the normally open state at the time of shifting of the gear ratio. However, this is due to the deterioration over time of the spring 126 that supports the valve element 114 of the hydraulic oil supply / discharge valve 110, excessive fluid force (the flow rate of hydraulic oil exceeding the expected range, the high viscosity of the hydraulic oil at low oil temperature, etc.). The case where the open state of the hydraulic oil supply / discharge valve 110 is not properly maintained due to the fluid force) can be assumed. In such a case, the gear ratio transition is not executed or is not continued, which is not preferable. Also, if the hydraulic oil supply / discharge valve fails and closes when the gear ratio is on the high speed side, downshifting cannot be performed, so the necessary driving force may not be ensured when the vehicle restarts or re-accelerates. There is.

  Therefore, in the belt-type continuously variable transmission 22 of the second embodiment, the configurations shown in the following fourth to sixth embodiments are employed in order to solve this problem.

(Embodiment 4)
FIGS. 9 and 10 are a flowchart (FIG. 9) and a time chart (FIG. 10) showing the operation of the belt type continuously variable transmission according to the fourth embodiment of the present invention. In the belt-type continuously variable transmission 22 according to the fourth embodiment, the hydraulic oil supply / discharge valve 110 is kept open when the gear ratio γ transition instruction (the hydraulic oil supply / discharge valve 110 open instruction) is ON. It is determined whether or not the operation has failed (detection of a failure in the open state maintaining operation of the hydraulic oil supply / discharge valve 110). Thereby, the fail safe of the hydraulic oil supply / discharge valve 110 is performed, and the reliability of the product is improved. This control is performed, for example, as follows (see FIGS. 9 and 10).

  In step S400, the transmission ratio γ transition instruction is set to ON (t = t41). The shift ratio γ is instructed by the ECU 140 turning on the opening instruction of the hydraulic oil supply / discharge valve 110 and turning on the solenoid valve 136a of the drive hydraulic chamber control device 136 (gear ratio change control). After step S400, the process proceeds to step S401.

  In step S401, it is determined whether or not the actual speed ratio γ has changed to the target speed ratio γtrg (t = t42). In this determination, when the gear ratio γ has not reached the target gear ratio γtrg after a lapse of a predetermined time from the transition instruction (t = t41) (t = t42), the hydraulic oil supply / discharge valve 110 is opened. It is estimated that the operation has failed and a negative determination is made. The gear ratio γ is calculated based on detection signals from the input rotation speed sensor 150, the output rotation speed sensor 160, and the like. If an affirmative determination is made in step S401, the process is terminated. If a negative determination is made, the process proceeds to step S402.

  In step S402, it is determined whether or not the drive hydraulic pressure Pcv of the actuator 120 is OFF (t = t43). The ON / OFF of the drive hydraulic pressure Pcv is determined based on the ON / OFF state of the solenoid valve 136a of the drive hydraulic chamber control device 136. If an affirmative determination is made in step S402, the process proceeds to step S403, and if a negative determination is made, the process proceeds to step S404.

  In step S403, it is determined that the holding operation of the hydraulic oil supply / discharge valve 110 in the open state has failed (t = t44). That is, if the opening / closing operation of the hydraulic oil supply / discharge valve 110 is normal, when the gear ratio γ transition instruction is turned ON, the drive hydraulic pressure Pcv of the actuator 120 is set to OFF and the hydraulic oil supply / discharge valve 110 opens. . However, the actual speed ratio is set in spite of the fact that a predetermined time has elapsed since the instruction to change the speed ratio γ (the instruction to open the hydraulic oil supply / discharge valve 110) is turned ON and the drive hydraulic pressure Pcv of the actuator 120 is set to OFF. When γ has not changed to the target gear ratio γtrg (step S400, negative determination in step S401 and positive determination in step S402), it is considered that the hydraulic oil supply / discharge valve 110 is closed for some reason. Accordingly, in such a case, it is determined that the holding operation of the opened state of the hydraulic oil supply / discharge valve 110 has failed, and a flag to that effect is set to ON (opening of the hydraulic oil supply / discharge valve 110). Detection of state holding action failure). After this step S403, the process ends.

  In step S404, it is determined whether or not the solenoid valve 136a of the drive hydraulic chamber control device 136 has failed. The failure of the solenoid valve 136a is performed by monitoring the current value or resistance value of the solenoid valve 136a, monitoring the drive hydraulic pressure Pcv of the actuator 120, and the like. If an affirmative determination is made in step S404, the process proceeds to one of steps S100 to S300 (see FIGS. 4-1, 5-1 and 7-1). That is, if the drive hydraulic pressure Pcv of the actuator 120 is not OFF despite the fact that the gear ratio γ transition instruction is ON (No in steps S400 and S402), the drive hydraulic chamber control device 136 It is considered that the solenoid valve 136a has failed. For example, it is considered that a disconnection failure has occurred in a normally open solenoid and a short failure has occurred in a normally closed solenoid. Therefore, in such a case, gear ratio control is performed when a failure occurs in the solenoid valve 136a (see the first to third embodiments). Thereby, since gear ratio control is performed appropriately, the reliability of a product improves. On the other hand, if a negative determination is made in step S404, the process ends.

  As described above, in the belt type continuously variable transmission 22 according to the fourth embodiment, a predetermined time has elapsed after the valve opening instruction (transition instruction for the gear ratio γ) of the hydraulic oil supply / discharge valve 110 is turned ON. When the actual speed ratio γ has not changed to the target speed ratio γtrg, it is determined that the holding operation of the opened state of the hydraulic oil supply / discharge valve 110 has failed (No in steps S400 and S401). Step S403) (see FIG. 9). In such a configuration, (1) when the open state of the hydraulic oil supply / discharge valve 110 cannot be maintained due to the fluid force of the hydraulic oil flowing into the primary pulley 50 (secondary pulley 60), for example, the transition of the gear ratio γ It is possible to appropriately determine the necessity of resuming the operation. Thereby, the fail safe of the hydraulic oil supply / discharge valve 110 is effectively performed, and there is an advantage that the reliability of the product is improved. Further, (2) when the hydraulic oil supply / discharge valve 110 cannot be kept open due to a malfunction of the hydraulic oil supply / discharge valve 110, the failure detection of the hydraulic oil supply / discharge valve 110 is properly performed. As a result, for example, a situation in which the engine speed becomes an abnormally high speed can be prevented in advance, and there is an advantage that the reliability of the product is improved.

(Embodiment 5)
11 and 12 are a flowchart (FIG. 11) and a time chart (FIG. 12) showing the operation of the belt type continuously variable transmission according to the fifth embodiment of the present invention. In these drawings, the same components as those of the belt-type continuously variable transmission 22 of the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  In the belt-type continuously variable transmission 22 of the fifth embodiment, when it is determined in the above-described fourth embodiment that the holding operation of the open state of the hydraulic oil supply / discharge valve 110 has failed, the supply hydraulic pressure Pin Is reduced. Thereby, fail safe of the hydraulic oil supply / discharge valve 110 is performed, and a situation where the hydraulic control device 130 supplies high-pressure hydraulic oil is prevented. For example, in this embodiment, the following gear ratio control is performed (see FIGS. 11 and 12).

  In step S500, the transmission ratio γ transition instruction is set to ON (t = t51). The shift ratio γ is instructed by the ECU 140 turning on the opening instruction of the hydraulic oil supply / discharge valve 110 and turning on the solenoid valve 136a of the drive hydraulic chamber control device 136 (gear ratio change control). After step S500, the process proceeds to step S501.

  In step S501, it is determined whether or not the holding operation of the hydraulic oil supply / discharge valve 110 has failed (t = t52). For this determination, the control of Embodiment 4 is used (see FIGS. 9 and 10). If an affirmative determination is made in step S501, the process proceeds to step S502. If a negative determination is made, the process ends.

  In step S502, the supply hydraulic pressure Pin is reduced (t = t53). For example, (1) a method of gradually reducing the supply oil pressure Pin, and (2) reducing the supply oil pressure Pin at a predetermined value α set in a range in which belt slippage due to pressure reduction does not occur. A method or the like can be adopted. After step S502, the process proceeds to step S503.

  In step S503, it is determined whether or not the shift of the gear ratio γ has been resumed (t = t54). In this determination, the actual speed ratio γ is calculated based on the output values of the input speed sensor 150 and the output speed sensor 160, and the presence or absence of transition of the speed ratio γ is estimated based on the actual speed ratio γ. If an affirmative determination is made in step S503, the process proceeds to step S504. If a negative determination is made, the process returns to step S502.

  In step S504, the supply of the supply hydraulic pressure Pin is resumed (t = t55). That is, when the shift of the gear ratio is restarted after the supply oil pressure Pin is reduced (step S503), it is estimated that the hydraulic oil supply / discharge valve 110 is in the open state (the closed state due to the failure has been released). The Therefore, by changing the hydraulic oil supply hydraulic pressure Pin to the hydraulic pressure before depressurization (transition), the gear ratio is properly changed. After step S504, the process proceeds to step S505.

  In step S505, it is determined whether or not the actual speed ratio γ has changed to the target speed ratio γtrg (t = t56). If an affirmative determination is made in step S505, the process is terminated. If a negative determination is made, the process returns to step S501.

  As described above, in the belt-type continuously variable transmission 22 of the fifth embodiment, when the holding operation of the open state of the hydraulic oil supply / discharge valve 110 fails, the supply hydraulic pressure Pin is reduced (step S501). Affirmative determination and step S502) (see FIG. 11). In such a configuration, when the hydraulic oil supply / discharge valve 110 fails and the gear ratio cannot be changed, a situation in which the hydraulic control device supplies high-pressure hydraulic oil is prevented. As a result, for example, a situation in which the engine speed becomes an abnormally high speed can be prevented in advance, and there is an advantage that the reliability of the product is improved. Further, in this configuration, when the hydraulic oil supply / discharge valve 110 fails and the gear ratio does not change, the shift of the gear ratio can be resumed by reducing the hydraulic oil supply hydraulic pressure Pin. Thereby, the fail safe of the hydraulic oil supply / discharge valve 110 is effectively performed, and there is an advantage that the reliability of the product is improved.

(Embodiment 6)
13 and 14 are a flowchart (FIG. 13) and a time chart (FIG. 14) showing the operation of the belt type continuously variable transmission according to the sixth embodiment of the present invention. In these drawings, the same components as those of the belt-type continuously variable transmission 22 of the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

In the belt-type continuously variable transmission 22 according to the sixth embodiment, when the failure of the holding operation in the open state of the hydraulic oil supply / discharge valve 110 occurs or may occur within a predetermined time,
The upper limit value of the transmission speed of the transmission ratio γ is set, and the transmission ratio γ is changed. Thereby, the fail safe of the hydraulic oil supply / discharge valve 110 is performed, and the situation where the shift ratio cannot be changed is avoided. For example, in this embodiment, the following gear ratio control is performed (see FIGS. 13 and 14).

  In step S600, it is determined whether or not the gear ratio γ transition instruction is set to ON (t = t61). That is, it is determined whether the opening instruction of the hydraulic oil supply / discharge valve 110 is set to ON. If an affirmative determination is made in step S600, the process proceeds to step S601. If a negative determination is made, the process ends.

  In step S601, it is determined whether there is a possibility that a failure in the holding operation of the hydraulic oil supply / discharge valve 110 in the open state may occur within a predetermined time (t = t62). In this determination, for example, an affirmative determination is made when (1) a failure has occurred within a predetermined time in the past (when there is a failure flag) or (2) when there is a cold flag. If an affirmative determination is made in step S601, the process proceeds to step S602. If a negative determination is made, the process ends.

  In step S602, an upper limit value α of the transmission speed Δ (dγ / dt) of the transmission ratio γ is set (t = t63). This upper limit value α is an allowable value of the shift speed and is defined by the following mathematical formula (3). In Equation (3), Toil is the oil temperature of the hydraulic oil, Fsp is the repulsive force of the spring 126, and As is the pressure receiving area of the movable sheave 53. After step S602, the process proceeds to step S603.

α = f (Toil, Fsp, As) (3)

  In step S603, a transition of the gear ratio γ is executed (t = t64) based on the transition instruction of the gear ratio γ (step S600). After step S603, the process proceeds to step S604.

  In step S604, it is determined whether or not the actual speed ratio γ has changed to the target speed ratio γtrg (t = t65). If an affirmative determination is made in step S604, the process is terminated. If a negative determination is made, the process returns to step S603.

  As described above, in the belt-type continuously variable transmission 22 of the sixth embodiment, when there is a high possibility that the holding operation of the hydraulic oil supply / discharge valve 110 will fail, the speed change speed Δ ( The upper limit value α of dγ / dt) is set, and the gear ratio γ is changed (steps S602 and S603) (see FIG. 13). In such a configuration, a situation in which the gear ratio does not change during the failure of the hydraulic oil supply / discharge valve 110 is avoided. Thereby, the fail safe of the hydraulic oil supply / discharge valve 110 is effectively performed, and there is an advantage that the reliability of the product is improved. Further, in such a configuration, the occurrence of engine stall is prevented when the gear ratio transition is not executed due to the failure of the hydraulic oil supply / discharge valve 110. This has the advantage that the reliability of the product is improved.

(Embodiment 7)
FIGS. 15-17 is explanatory drawing (FIG. 15), flowchart (FIG. 16), and time chart (FIG. 17) which show the effect | action of the belt-type continuously variable transmission concerning Embodiment 7 of this invention. In these drawings, the same components as those of the belt-type continuously variable transmission 22 of the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  In the belt-type continuously variable transmission 22 according to the seventh embodiment, when it is estimated that the holding operation of the hydraulic oil supply / discharge valve 110 in the open state has failed due to an imbalance between the supply hydraulic pressure Pin and the primary hydraulic pressure Ps. The supply hydraulic pressure Pin is reduced. Thereby, it is possible to resume the shift of the gear ratio. For example, in this embodiment, the following gear ratio control is performed (see FIGS. 15 to 17).

  In step S700, the transmission ratio γ transition instruction is set to ON (t = t71). As a result, the opening instruction of the hydraulic oil supply / discharge valve 110 is turned ON, and the hydraulic oil of the supply hydraulic pressure Pin is supplied from the hydraulic control device 130 via the hydraulic oil supply / discharge valve 110 to the primary hydraulic chamber 54 of the movable sheave 53 (63). Begins to be fed into. After step S700, the process proceeds to step S701.

  In step S701, it is determined whether the opening operation of the hydraulic oil supply / discharge valve 110 has failed (t = t72). In this determination, the actual speed ratio γ is calculated based on the detection signals of the input speed sensor 150 and the output speed sensor 160, and the actual speed ratio γ is determined after a lapse of a predetermined time from the time of transition instruction (t = t71) ( An affirmative determination is made when the target gear ratio γtrg is not reached at t = t72). For example, although the opening instruction of the hydraulic oil supply / discharge valve 110 is turned ON by the shift ratio γ transition instruction (step S700), the opening operation of the hydraulic oil supply / discharge valve 110 is delayed, and the transmission ratio γ It is assumed that the transition of is not started. If an affirmative determination is made in step S701, the process proceeds to step S702. If a negative determination is made, the process ends.

  In step S702, it is determined whether or not the solenoid valve 136a of the drive hydraulic chamber control device 136 has failed (t = t73). The failure of the solenoid valve 136a is performed by monitoring the current value or resistance value of the solenoid valve 136a, monitoring the drive hydraulic pressure Pcv of the actuator 120, and the like. If an affirmative determination is made in step S702, the process proceeds to one of steps S100 to S300 (see FIGS. 4-1, 5-1 and 7-1). That is, when the hydraulic oil supply / discharge valve 110 is not in the open state despite the fact that the gear ratio γ transition instruction is ON (affirmative determination in step S700 and step S701), the drive hydraulic chamber control device 136 It is considered that the solenoid valve 136a has failed. Therefore, in such a case, gear ratio control is performed when a failure occurs in the solenoid valve 136a (see the first to third embodiments). Thereby, since gear ratio control is performed appropriately, the reliability of a product improves. On the other hand, if a negative determination is made in step S702, the process proceeds to step S703.

  In step S703, it is determined whether or not the supply hydraulic pressure Pin of the hydraulic control device 130 and the primary hydraulic pressure Ps of the movable sheave 53 (63) have a relationship of Pin> Ps (t = t74). For example, in this embodiment, the pair of hydraulic sensors 181 and 182 that measure the hydraulic pressure of the hydraulic oil are in the second oil passage 102 and are closer to the hydraulic control device 130 and the primary hydraulic chamber 54 than the hydraulic oil supply / discharge valve 110. It arrange | positions at the side, respectively (refer FIG. 15). Then, the output signal of the hydraulic sensor 181 on the hydraulic control device 130 side is acquired as the supply hydraulic pressure Pin, and the output signal of the hydraulic sensor 182 on the primary hydraulic chamber 54 side is acquired as the primary hydraulic pressure Ps. Then, based on these output signals, the ECU 140 determines the relationship (Pin> Ps) between the supply hydraulic pressure Pin and the primary hydraulic pressure Ps. If an affirmative determination is made in step S703, the process proceeds to step S704. If a negative determination is made, the process ends.

  In step S704, the supply hydraulic pressure Pin is reduced (t = t75). That is, when the supply hydraulic pressure Pin and the primary hydraulic pressure Ps have a relationship of Pin> Ps (affirmative determination in step S703), the open state of the hydraulic oil supply / discharge valve 110 due to the unbalance of the hydraulic pressures Pin and Ps. It is thought that the holding operation of Therefore, in such a case, the hydraulic control device 130 reduces the hydraulic oil supply hydraulic pressure Pin. For example, (1) a method of gradually reducing the supply oil pressure Pin, and (2) a method of reducing the supply oil pressure Pin at a predetermined value α set in a range in which belt slippage due to pressure reduction does not occur. A method for reducing the pressure may be employed. After step S704, the process proceeds to step S705.

  In step S705, it is determined whether or not the speed ratio γ transition has been resumed (t = t76). In this determination, the actual speed ratio γ is calculated based on the output values of the input speed sensor 150 and the output speed sensor 160, and the presence or absence of transition of the speed ratio γ is estimated based on the actual speed ratio γ. If an affirmative determination is made in step S705, the process proceeds to step S706, and if a negative determination is made, the process returns to step S704.

  In step S706, the supply of the supply hydraulic pressure Pin is resumed (t = t77). That is, when the shift of the gear ratio is resumed after the pressure reduction of the supply hydraulic pressure Pin (step S704), it is estimated that the hydraulic oil supply / discharge valve 110 is in the open state (the closed state due to the failure has been released). The Therefore, by changing the hydraulic oil supply hydraulic pressure Pin to the hydraulic pressure before depressurization (transition), the gear ratio is properly changed. After step S706, the process proceeds to step S707.

  In step S707, it is determined whether or not the actual speed ratio γ has transitioned to the target speed ratio γtrg. Then, after the actual speed ratio γ transitions to the target speed ratio γtrg (γ = γtrg), the processing is terminated.

  As described above, in the belt type continuously variable transmission 22 of the seventh embodiment, the holding operation of the hydraulic oil supply / discharge valve 110 in the open state has failed, and the supply hydraulic pressure Pin of the hydraulic control device 130 and When the primary hydraulic pressure Ps of the movable sheave 53 has a relationship of Pin> Ps, the supply hydraulic pressure Pin is reduced (positive determination in step S701, positive determination in step S703, and step S704) (see FIG. 16). In such a configuration, when the hydraulic oil supply / discharge valve 110 fails due to an imbalance between the supply hydraulic pressure Pin and the primary hydraulic pressure Ps, the shift of the gear ratio can be resumed by reducing the supply hydraulic pressure Pin. Thereby, the fail safe of the hydraulic oil supply / discharge valve 110 is effectively performed, and there is an advantage that the reliability of the product is improved. Further, in this configuration, when the hydraulic oil supply / discharge valve 110 fails and the gear ratio cannot be changed, a situation where the hydraulic control device supplies high-pressure hydraulic oil is prevented. As a result, for example, a situation in which the engine speed becomes an abnormally high speed or a situation in which an engine stall occurs can be prevented in advance, which has the advantage of improving the reliability of the product.

  In the belt type continuously variable transmission 22 of the seventh embodiment, a pair of hydraulic sensors 181 and 182 are disposed in the second oil passage 102 to supply the hydraulic pressure Pin supplied from the hydraulic control device 130 and the primary hydraulic pressure of the movable sheave 53. Ps is acquired (see FIG. 15). In such a configuration, the supply oil pressure Pin and the primary oil pressure Ps are acquired as actual measurement values by the oil pressure sensors 181 and 182, which is preferable in that the accuracy of the comparison determination (step S703) between the supply oil pressure Pin and the primary oil pressure Ps is improved. .

  However, the present invention is not limited to this, and only the hydraulic sensor 181 that measures the supplied hydraulic pressure Pin may be installed, and the hydraulic sensor 182 that measures the primary hydraulic pressure Ps may be omitted (see FIG. 18). Then, the supply hydraulic pressure Pin is acquired as an actual measurement value by the hydraulic pressure sensor 181, and the primary hydraulic pressure Ps is acquired as an estimated value calculated based on output signals of other sensors. In such a configuration, since the hydraulic pressure sensor 182 that measures the primary hydraulic pressure Ps can be omitted, there is an advantage that the cost of the product can be reduced.

  Note that the estimated value of the primary hydraulic pressure Ps is calculated using, for example, the following formula (4). In Equation (4), Te is the engine torque, Nin is the input rotational speed, Pd is the secondary hydraulic pressure, and γ is the gear ratio.

  Ps = f (Te, Nin, Pd, γ) (4)

(Embodiment 8)
19 and 20 are a flowchart (FIG. 19) and a time chart (FIG. 20) showing the operation of the belt type continuously variable transmission according to the eighth embodiment of the present invention. In these drawings, the same components as those of the belt-type continuously variable transmission 22 of the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  In the belt type continuously variable transmission 22 of the eighth embodiment, when there is a high possibility that the holding operation of the hydraulic oil supply / discharge valve 110 will fail, the hydraulic oil supply / discharge is started prior to the start of supply of the hydraulic pressure Pin. The valve opening operation of the valve 110 is started. Then, after the start of the transition of the gear ratio γ is confirmed, the supply of the supply hydraulic pressure Pin is started. Thereby, the fail safe at the time of failure of the hydraulic oil supply / discharge valve 110 is realized. For example, in this embodiment, the following gear ratio control is performed (see FIGS. 19 and 20).

  In step S800, it is determined whether or not the transmission ratio γ transition instruction is ON (t = t81). That is, it is determined whether the opening instruction of the hydraulic oil supply / discharge valve 110 is ON. If an affirmative determination is made in step S800, the process proceeds to step S801. If a negative determination is made, the process ends.

  In step S801, it is determined whether there is a possibility that a failure in the holding operation of the hydraulic oil supply / discharge valve 110 will occur within a predetermined time (t = t82). In step S801, for example, an affirmative determination is made when (1) a failure has occurred within a predetermined time in the past (when there is a failure flag), or (2) when there is a cold flag. If an affirmative determination is made in step S801, the process proceeds to step S802. If a negative determination is made, the process ends.

  In step S802, the drive hydraulic pressure Pcv of the actuator 120 is set to OFF (released) (t = t83). As a result, the opening operation of the hydraulic oil supply / discharge valve 110 is started. After step S802, the process proceeds to step S803.

  In step S803, it is determined whether or not a shift of the gear ratio γ is started (t = t84). In this determination, the actual speed ratio γ is calculated based on the output values of the input speed sensor 150 and the output speed sensor 160, and it is determined based on the actual speed ratio γ whether or not the transition of the speed ratio γ has started. If an affirmative determination is made in step S803, the process proceeds to step S804, and if a negative determination is made, the process ends.

  In step S804, supply of the supply hydraulic pressure Pin is started (t = t85). In this embodiment, the supplied hydraulic pressure Pin is acquired as an estimated value calculated based on the engine torque Te, the input rotational speed Nin, the secondary hydraulic pressure Pd, and the gear ratio γ. Further, the mathematical formula (5) is used to calculate the estimated value of the supply hydraulic pressure Pin. After step S804, the process proceeds to step S805.

Pin = f (Te, Nin, Pd, γ) (5)

  In step S805, it is determined whether or not the actual speed ratio γ has changed to the target speed ratio γtrg (t = t86). Then, after the actual speed ratio γ transitions to the target speed ratio γtrg (γ = γtrg), the processing is terminated.

  As described above, in the belt-type continuously variable transmission 22 of the eighth embodiment, the opening instruction of the hydraulic oil supply / discharge valve 110 is ON and the holding operation of the hydraulic oil supply / discharge valve 110 in the open state is failed. When there is a high possibility of this, the opening operation of the hydraulic oil supply / discharge valve 110 is started prior to the start of supply of the supply hydraulic pressure Pin (steps S801 and S802) (see FIG. 19). Then, after confirming the start of the shift of the gear ratio γ, the supply of the supply hydraulic pressure Pin is started (steps S803 and S804). With such a configuration, it is possible to avoid a situation in which transition of the gear ratio cannot be performed when the hydraulic oil supply / discharge valve 110 fails. Thereby, the fail safe of the hydraulic oil supply / discharge valve 110 is effectively performed, and there is an advantage that the reliability of the product is improved. Further, in such a configuration, the occurrence of engine stall is prevented when the gear ratio transition is not executed due to the failure of the hydraulic oil supply / discharge valve 110. This has the advantage that the reliability of the product is improved.

(Embodiment 9)
FIGS. 21 and 22 are a flowchart (FIG. 21) and a time chart (FIG. 22) showing the operation of the belt type continuously variable transmission according to the ninth embodiment of the present invention. In these drawings, the same components as those of the belt-type continuously variable transmission 22 of the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  In the belt type continuously variable transmission 22 according to the ninth embodiment, when the hydraulic oil supply / discharge valve 110 is highly likely to fail, the hydraulic oil supply hydraulic pressure Pin is set lower than the primary hydraulic pressure Ps of the movable sheave. Thereby, the shift of the gear ratio can be performed, and the fail safe of the hydraulic oil supply / discharge valve 110 is effectively performed. For example, in this embodiment, the following gear ratio control is performed (see FIGS. 21 and 22).

  In step S900, it is determined whether or not the gear ratio γ transition instruction is ON (t = t91). That is, it is determined whether the opening instruction of the hydraulic oil supply / discharge valve 110 is ON. If an affirmative determination is made in step S900, the process proceeds to step S901. If a negative determination is made, the process ends.

  In step S901, it is determined whether there is a possibility that a failure in the holding operation of the hydraulic oil supply / discharge valve 110 will occur within a predetermined time (t = t92). In step S901, an affirmative determination is made, for example, when (1) a failure has occurred within a predetermined time in the past (when there is a failure flag), or (2) when there is a cold flag. If an affirmative determination is made in step S901, the process proceeds to step S902. If a negative determination is made, the process ends.

  In step S902, the primary hydraulic pressure Ps of the movable sheave 53 is acquired (t = t93). The primary oil pressure Ps may be acquired based on an output signal of the oil pressure sensor 182 (see FIG. 15), or an estimated value calculated based on the engine torque Te, the input rotation speed Nin, the secondary oil pressure Pd, and the gear ratio γ. (See Formula (4)).

  In step S903, the supply oil pressure Pin is set to a low oil pressure having a predetermined differential pressure α = Ps−Pin with respect to the primary oil pressure Ps acquired in step S902 (t = t94). This supply oil pressure Pin (differential pressure α) is the amount of transition of the gear ratio γ that occurs when the supply oil pressure Pin is insufficient due to the differential pressure α in the open state of the hydraulic oil supply / discharge valve 110, and the movement of the movable sheave 53. It is calculated on the basis of the amount, fluctuation amount of the engine speed, and the like. After step S903, the process proceeds to step S904.

  In step S904, the drive hydraulic pressure Pcv of the actuator 120 is set to OFF (released) (t = t95). As a result, the opening operation of the hydraulic oil supply / discharge valve 110 is started. After step S904, the process proceeds to step S905.

  In step S905, it is determined whether or not a shift of the gear ratio γ is started (t = t96). In this determination, the actual speed ratio γ is calculated based on the output values of the input speed sensor 150 and the output speed sensor 160, and it is determined based on the actual speed ratio γ whether or not the transition of the speed ratio γ has started. If an affirmative determination is made in step S905, the process proceeds to step S906, and if a negative determination is made, the process proceeds to step S700 of the seventh embodiment (see FIG. 16).

  In step S906, it is determined whether or not the actual speed ratio γ has changed to the target speed ratio γtrg (t = t97). Then, after the actual speed ratio γ transitions to the target speed ratio γtrg (γ = γtrg), the processing is terminated.

  As described above, in the belt-type continuously variable transmission 22 according to the ninth embodiment, when the holding operation of the open state of the hydraulic oil supply / discharge valve 110 is highly likely to fail, the supply hydraulic pressure Pin is changed to the movable sheave 53. Is set to a hydraulic pressure having a predetermined differential pressure α = Ps−Pin with respect to the primary hydraulic pressure Ps (Yes in step S901 and step S903). In such a configuration, when there is a high possibility that the hydraulic oil supply / discharge valve 110 will fail, the hydraulic oil supply hydraulic pressure Pin is set lower than the primary hydraulic pressure Ps of the movable sheave. Become. Thereby, the fail safe of the hydraulic oil supply / discharge valve 110 is effectively performed, and there is an advantage that the reliability of the product is improved. Further, in this configuration, when the hydraulic oil supply / discharge valve 110 fails and the gear ratio cannot be changed, a situation where the hydraulic control device supplies high-pressure hydraulic oil is prevented. As a result, for example, a situation in which the engine speed becomes an abnormally high speed can be prevented in advance, and there is an advantage that the reliability of the product is improved.

  As described above, the belt type continuously variable transmission according to the present invention is useful in that the reliability of the product can be improved by effectively performing the fail safe of the hydraulic oil supply / discharge valve.

DESCRIPTION OF SYMBOLS 10 Vehicle, 12 Internal combustion engine, 14 Crankshaft, 16 Torque converter, 18 Input shaft, 20 Forward / reverse switching mechanism, 22 Belt type continuously variable transmission, 24 Reduction device, 26 Final drive pinion, 28 Differential device, 30 Ring gear, 32 Drive shaft, 34 Drive wheel, 50 Primary pulley, 51 Primary shaft, 52 Primary fixed sheave, 53 Primary movable sheave, 54 Primary hydraulic chamber, 55 Spline, 56 Primary partition, 60 Secondary pulley, 61 Secondary shaft, 62 Secondary fixed sheave 63 secondary movable sheave, 64 secondary hydraulic chamber, 80 belt, 80b secondary groove, 80a primary groove, 80a groove, 81-84 bearing, 86 oil passage, 88 axial oil passage , 90 radial oil passage, 100 switching mechanism, 102 second oil passage, 110 hydraulic oil supply / discharge valve, 112 valve seat, 114 valve body, 120 actuator, 122 piston, 124 drive hydraulic chamber, 126 spring, 130 hydraulic oil supply Drain valve 110 Hydraulic control device, 131 Oil pan, 132 Oil pump, 133 Line pressure control device, 134 Constant pressure control device, 135 Primary hydraulic chamber control device, 136 Drive hydraulic chamber control device, 137 Secondary hydraulic chamber control device , 150 input rotation speed sensor, 160 output rotation speed sensor, 170 vehicle speed sensor, 181 and 182 oil pressure sensor, 222 belt type continuously variable transmission, 322 belt type continuously variable transmission, R1 to R9 oil passage, RL rotation axis

Claims (3)

A movable sheave that is driven by hydraulic oil to change the clamping pressure of the belt, a hydraulic control device that controls the hydraulic pressure of the hydraulic oil, and a hydraulic oil that is disposed on the hydraulic oil passage from the hydraulic control device to the movable sheave A belt type continuously variable transmission comprising a hydraulic oil supply / discharge valve that regulates the flow of
When the transmission gear ratio is changed, the hydraulic oil supply / discharge valve is opened and the hydraulic control device supplies hydraulic oil of a predetermined supply hydraulic pressure Pin to the movable sheave to drive the movable sheave. The upper limit value of the transmission speed of the transmission gear ratio is set when the holding pressure of the hydraulic oil is controlled and there is a high possibility that the holding operation of the open state of the hydraulic oil supply / discharge valve will fail. Type continuously variable transmission.   When the opening instruction of the hydraulic oil supply / discharge valve is ON and the holding operation of the open state of the hydraulic oil supply / discharge valve is highly likely to fail, the opening operation of the hydraulic oil supply / discharge valve starts. The belt-type continuously variable transmission according to claim 1, wherein the start of transition of the transmission gear ratio is confirmed and supply of the supply hydraulic pressure Pin is started thereafter.   When there is a high possibility that the holding operation in the open state of the hydraulic oil supply / discharge valve will fail, the supply hydraulic pressure Pin becomes a hydraulic pressure having a predetermined differential pressure α = Ps−Pin with respect to the primary hydraulic pressure Ps of the movable sheave. The belt-type continuously variable transmission according to claim 1 or 2, which is set.

Images