JP6031391B2 - Continuously variable transmission and control method - Google Patents

Description

  The present invention relates to a continuously variable transmission.

  Conventionally, movable teeth urged radially outward by a spring are provided on the shaft portion of the pulley, a meshing groove is provided on the endless chain link, and the meshing groove is made movable when the gear ratio is, for example, the highest gear ratio. Patent Document 1 discloses a continuously variable transmission that meshes.

JP 2010-014269 A

  In the above continuously variable transmission, if the movable teeth, springs, etc. are not functioning due to damage, etc., the meshing groove will not mesh with the movable teeth and slip will occur between the endless chain link and the pulley. Therefore, it is necessary to detect whether or not the meshing groove and the movable tooth are normally meshed.

  This invention is invented in view of such a point, and it aims at detecting whether a meshing groove and a movable tooth mesh normally.

  A continuously variable transmission according to an aspect of the present invention includes a first pulley having a first fixed conical plate and a first movable conical plate that moves in an axial direction in accordance with hydraulic pressure supplied to and discharged from the first oil chamber, A second pulley having a fixed conical plate, a second movable conical plate that moves in the axial direction according to the hydraulic pressure supplied to and discharged from the second oil chamber, and a movable tooth that is movable in the radial direction of the shaft portion; An annular belt member that is wound between a pulley and a second pulley to transmit power between the first pulley and the second pulley, and a groove that can mesh with the movable tooth is formed on the inner peripheral surface; A continuously variable transmission that includes a biasing means that biases the movable tooth radially outward of the shaft portion; a meshing determination means that determines whether the groove meshes with the movable tooth; If the gear ratio is a predetermined gear ratio that meshes with the tooth, and the mesh determination means determines that the groove is not meshed with the movable tooth, the movable tooth Biasing means, and an abnormality determination unit that determines an abnormality in at least one of the strip occurs.

  The control method according to another aspect of the present invention includes a first pulley having a first movable conical plate and a first movable conical plate that moves in an axial direction in accordance with hydraulic pressure supplied to and discharged from the first oil chamber, and a second pulley. A second pulley having a fixed conical plate, a second movable conical plate that moves in the axial direction according to the hydraulic pressure supplied to and discharged from the second oil chamber, and a movable tooth that is movable in the radial direction of the shaft portion; An annular belt member that is wound between the first pulley and the second pulley, transmits power between the first pulley and the second pulley, and has a groove that engages with the movable teeth on the inner peripheral surface, and is movable. A control method for controlling a continuously variable transmission comprising a biasing means for biasing teeth radially outward of a shaft portion, wherein it is determined whether or not the groove meshes with a movable tooth, and the gear ratio is movable If it is determined that the gear ratio meshes with the teeth and the groove does not mesh with the movable teeth, the number of movable teeth, biasing means, and belt Even Ku determines that the abnormality in any one has occurred.

  According to these aspects, when it is determined that the groove is not meshed with the movable tooth even though the gear ratio is a predetermined gear ratio in which the groove provided in the belt body meshes with the movable tooth, the movable tooth By determining that an abnormality has occurred in at least one of the biasing means and the belt, it is possible to detect a state where the groove and the movable tooth are not normally meshed with each other.

It is a schematic block diagram of the continuously variable transmission of 1st Embodiment. It is the schematic of the secondary pulley which removed the chain. It is a schematic perspective view of the output shaft part of a secondary pulley. It is the schematic sectional drawing which cut | disconnected the secondary pulley along the axial direction of an output shaft. It is a figure which shows the state which a movable cone plate moves to the fixed cone plate side in FIG. It is a schematic block diagram of a spring. It is a conceptual diagram of the hydraulic control unit and CVT control unit of 1st Embodiment. It is a flowchart explaining the shift control of 1st Embodiment. It is a flowchart explaining the shift control of 1st Embodiment. It is a flowchart explaining the shift control of 1st Embodiment. It is a map which shows the relationship between a transmission difference thrust and a target line pressure. It is a map which shows the relationship between target line pressure and a line pressure solenoid command value. It is a map which shows the relationship between a target primary pulley pressure and a primary pulley pressure solenoid command value. It is a map which shows the relationship between a target secondary pulley pressure and a secondary pulley pressure solenoid command value. It is a map which shows the relationship between stroke amount and secondary pulley thrust reduction amount. It is a conceptual diagram of the hydraulic control unit and CVT control unit of 2nd Embodiment. It is a flowchart explaining the shift control of 2nd Embodiment. It is a flowchart explaining the shift control of 2nd Embodiment. It is a flowchart explaining the shift control of 2nd Embodiment. It is a map which shows the relationship between a target gear ratio and a step motor position. It is a flowchart explaining the shift control of 3rd Embodiment. It is a flowchart explaining the shift control of 3rd Embodiment. It is a flowchart explaining the shift control of 3rd Embodiment. It is a map which shows the relationship between a deviation and the secondary pulley pressure reduction amount.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the following description, the “speed ratio” is a value obtained by dividing the input rotational speed of a chain type continuously variable transmission (hereinafter referred to as a continuously variable transmission) by the output rotational speed. The continuously variable transmission becomes higher as the gear ratio is smaller. FIG. 1 is a schematic configuration diagram of a continuously variable transmission according to the first embodiment.

  The continuously variable transmission 5 is connected to the engine 1 via a torque converter 2 having a lock-up clutch and a forward / reverse switching mechanism 4. The continuously variable transmission 5 includes a primary pulley 10 to which driving force is transmitted from the engine 1, a secondary pulley 11 connected to the output shaft 13, and an endless chain link that is wound around the primary pulley 10 and the secondary pulley 11. (Hereinafter referred to as a chain) 12. The output shaft 13 is connected to the differential 6 via an idler gear 14.

  The chain 12 is a band formed by connecting a large number of links with link pins to form an annular shape. As shown in FIG. 4, a meshing groove 12 a that can mesh with a tooth portion 53 of a movable tooth 40 described later is formed on the inner peripheral surface of the chain 12. The meshing refers to a state in which the meshing groove 12 a and the tooth portion 53 overlap in the radial direction of the output shaft 13 and power is transmitted between the meshing groove 12 a and the tooth portion 53. Since the meshing groove 12 a meshes with the movable tooth 40, it is possible to suppress the occurrence of slip between the chain 12 and the secondary pulley 11.

  The primary pulley 10 includes a fixed conical plate 10b that rotates integrally with the input shaft, and a movable conical plate 10a that is disposed to face the fixed conical plate 10b and forms a V-shaped pulley groove. The movable conical plate 10a is displaced in the axial direction of the input shaft when primary pulley pressure is supplied to and discharged from the primary pulley cylinder chamber 10c.

  The secondary pulley 11 includes a fixed conical plate 11 b that rotates integrally with the output shaft 13, a movable conical plate 11 a that is disposed opposite to the fixed conical plate 11 b to form a V-shaped pulley groove, and a shaft of the output shaft 13. A movable tooth 40 formed along the direction and a spring 41 that urges the movable tooth 40 outward in the radial direction of the output shaft 13 are provided. The secondary pulley 11 will be described in detail with reference to FIGS. FIG. 2 is a schematic view of the secondary pulley 11 with the chain 12 removed. FIG. 3 is a schematic perspective view of the output shaft 13 portion of the secondary pulley 11. FIG. 4 is a schematic cross-sectional view of the secondary pulley 11 cut along the axial direction of the output shaft 13.

  The movable tooth 40 is movable in the radial direction of the output shaft 13 in each of a plurality of movable tooth guide grooves 42 provided on the outer peripheral surface of the output shaft 13 at equal intervals in the circumferential direction and along the axial direction. It is provided as follows. The movable tooth 40 rotates integrally with the output shaft 13.

  The movable tooth 40 includes a base 50 extending in the axial direction of the output shaft 13, a first stopper 51 projecting radially outward from the end of the base 50 on the fixed conical plate 11 b side, and a movable cone in the base 50. A second stopper 52 projecting radially outward of the output shaft 13 from the end on the plate 11a side, and a tooth projecting radially outward of the output shaft 13 from the base 50 between the first stopper 51 and the second stopper 52 Part 53.

  The movable tooth 40 is pushed outward in the radial direction of the output shaft 13 by a spring 41 provided between the base 50 and the output shaft 13. The movable tooth 40 moves in the radial direction of the output shaft 13 according to the elastic force of the spring 41 and the pressing force generated when the meshing groove 12 a of the chain 12 meshes with the movable tooth 40. When there is no pressing force or when the elastic force is larger than the pressing force, the first stopper 51 contacts the inner peripheral surface 11d of the fixed conical plate 11b, and the second stopper 52 is the inner peripheral surface of the movable conical plate 11a. 11e. In this way, the first stopper 51 contacts the inner peripheral surface 11d of the fixed conical plate 11b, and the second stopper 52 contacts the inner peripheral surface 11e of the movable conical plate 11a. Movement to the outside in the radial direction is restricted. When the pressing force is larger than the elastic force, the movable tooth 40 moves to the output shaft 13 side and is held at a position where the elastic force and the pressing force are balanced.

  The tooth portion 53 is formed along the axial direction of the output shaft 13 and is formed according to the shape of the meshing groove 12 a of the chain 12. The tooth tip of the tooth portion 53 is formed so as not to protrude outward in the radial direction of the output shaft 13 from the inner peripheral surfaces 11d and 11e. Therefore, the movable conical plate 11a can move in the axial direction of the output shaft 13 without interfering with the tooth portion 53, as shown in FIG. FIG. 5 is a diagram illustrating a state in which the movable conical plate 11a moves to the fixed conical plate 11b side in FIG.

  As shown in FIG. 6, the spring 41 is configured by arranging linear U-shaped elements 60 and linear connecting elements 61 alternately on the same circumference. FIG. 6 is a schematic configuration diagram of the spring 41. In the present embodiment, as shown in FIG. 4, the three springs 41 are arranged in the axial direction of the output shaft 13.

  The connecting element 61 engages with a groove 13a provided in the circumferential direction of the output shaft 13, and movement of the output shaft 13 inward in the radial direction is restricted by a groove bottom 13b.

  The U-shaped element 60 is provided such that a U-shaped bottom portion 60 a is positioned on the radially outer side of the output shaft 13 with respect to the connecting element 61, and the bottom portion 60 a abuts on the movable tooth 40. The elastic force of the spring 41 increases as the movable tooth 40 is pushed radially inward of the output shaft 13. The U-shaped elements 60 are provided in the same number as the movable teeth 40, and the elastic force that each movable tooth 40 receives from the U-shaped elements 60 varies depending on the contact state between each movable tooth 40 and the chain 12.

  The movable conical plate 11a is displaced in the axial direction of the output shaft 13 when the secondary pulley pressure is supplied to and discharged from the secondary pulley cylinder chamber 11c.

  The continuously variable transmission 5 changes speed by changing the balance between the primary pulley pressure and the secondary pulley pressure.

  The transmission ratio of the continuously variable transmission 5 and the thrust of the pulleys 10 and 11 are controlled by a hydraulic control unit 100 that responds to a command from the CVT control unit 20. The CVT control unit 20 determines and controls the target gear ratio and thrust based on engine output torque information output from the engine control unit 21 that controls the engine 1 and signals output from sensors and the like described later.

  The driving torque generated in the engine 1 is input to the primary pulley 10 of the continuously variable transmission 5 via the torque converter 2 and the forward / reverse switching mechanism 4 and is transmitted from the primary pulley 10 to the secondary pulley 11 via the chain 12. . By moving the movable conical plate 10a of the primary pulley 10 and the movable conical plate 11a of the secondary pulley 11 in the axial direction, the primary pulley 10 and the chain 12 and the contact radius between the secondary pulley 11 and the chain 12 are changed. And the gear ratio in the secondary pulley 11 is continuously changed.

  As shown in FIG. 7, the hydraulic control unit 100 includes a regulator valve 32 that controls the line pressure, a pressure reducing valve 30 that controls the primary pulley pressure, and a pressure reducing valve 34 that controls the secondary pulley pressure. FIG. 7 is a conceptual diagram of the hydraulic control unit 100 and the CVT control unit 20 in the first embodiment.

  The regulator valve 32 includes a solenoid 33 that regulates the pressure of oil discharged from an oil pump 36 that is driven by transmission of part of the driving torque generated in the engine 1. The regulator valve 32 adjusts the pressure of the oil discharged from the oil pump 36 to a predetermined line pressure corresponding to the operating state in accordance with a command (for example, a duty signal) from the CVT control unit 20.

  The pressure reducing valve 30 includes a solenoid 31 that regulates the line pressure. The pressure reducing valve 30 adjusts the line pressure to a predetermined primary pulley pressure in accordance with a command (for example, a duty signal) from the CVT control unit 20. The primary pulley pressure is supplied to and discharged from the primary pulley cylinder chamber 10c.

  The pressure reducing valve 34 includes a solenoid 35 that regulates the line pressure. The pressure reducing valve 34 adjusts the line pressure to a predetermined secondary pulley pressure in accordance with a command (for example, a duty signal) from the CVT control unit 20. The secondary pulley pressure is supplied to and discharged from the secondary pulley cylinder chamber 11c.

  The CVT control unit 20 includes a signal from the inhibitor switch 22, a signal from the accelerator pedal sensor 23, a signal from the primary pulley rotational speed sensor 24, a signal from the secondary pulley rotational speed sensor 25, a signal from the brake pedal sensor 26, the engine Based on the signal from the control unit 21, the gear ratio and the like are controlled. The engine control unit 21 sends information such as engine rotation speed and engine output torque based on a signal from the engine rotation speed sensor 29.

  In the continuously variable transmission 5, when changing the gear ratio to High side, for example, the highest level, a part of the meshing groove 12 a of the chain 12 starts to mesh with the movable teeth 40 before the gear ratio becomes the highest level. A part of the movable teeth 40 is pushed inward in the radial direction of the output shaft 13 by the chain 12. Even when a part of the meshing groove 12 a of the chain 12 meshes with the movable tooth 40, the other part of the meshing groove 12 a of the chain 12 does not mesh with the movable tooth 40, and the chain 12 moves to the movable tooth 40. Is pushed inward in the radial direction of the output shaft 13. Therefore, after the gear ratio becomes the gear ratio at which the meshing groove 12a of the chain 12 starts to mesh with the movable teeth 40, the elastic force by the spring 41 acts on the chain 12, and the elastic force by the spring 41 is taken into consideration. You have to change the speed.

  The speed change control of the present embodiment facilitates the change to the speed change ratio at which the meshing groove 12a of the chain 12 meshes with the movable teeth 40 by adjusting the secondary pulley pressure in the above situation.

  Next, the shift control in this embodiment will be described with reference to the flowcharts of FIGS.

  In step S100, the CVT control unit 20 determines whether or not a failure determination flag described later in detail is “1”. The process proceeds to step S138 when the failure determination flag is “1”, and proceeds to step S101 when the failure determination flag is “0”.

  In step S101, the CVT control unit 20 calculates the target gear ratio from the shift line map based on the input torque, the throttle opening, the vehicle speed, and the position of the select lever (step S101 constitutes the target gear ratio calculating means. ). The throttle opening is detected based on a signal from the accelerator pedal sensor 23. The vehicle speed is detected based on a signal from a wheel speed sensor (not shown). The position of the selector lever is detected based on a signal from the inhibitor switch 22.

  In step S102, the CVT control unit 20 calculates a basic primary pulley thrust and a basic secondary pulley thrust based on the target gear ratio. The basic primary pulley thrust and the basic secondary pulley thrust are thrusts obtained by adding a safety allowance to the minimum thrust limit value necessary to realize the target gear ratio.

  In step S103, the CVT control unit 20 determines whether the basic primary pulley thrust is equal to or greater than the minimum primary pulley thrust. The process proceeds to step S105 when the basic primary pulley thrust is greater than or equal to the minimum primary pulley thrust, and proceeds to step S104 when the basic primary pulley thrust is smaller than the minimum primary pulley thrust.

  In step S104, the CVT control unit 20 sets the minimum primary pulley thrust to the basic primary pulley thrust.

  In step S105, the CVT control unit 20 determines whether the basic secondary pulley thrust is equal to or greater than the minimum secondary pulley thrust. The process proceeds to step S107 when the basic secondary pulley thrust is greater than or equal to the minimum secondary pulley thrust, and proceeds to step S106 when the basic secondary pulley thrust is smaller than the minimum secondary pulley thrust.

  In step S106, the CVT control unit 20 sets the minimum secondary pulley thrust to the basic secondary pulley thrust.

  In step S107, the CVT control unit 20 calculates a shift difference thrust based on the basic primary pulley thrust and the basic secondary pulley thrust.

  In step S108, the CVT control unit 20 calculates the target line pressure from the shift difference thrust map shown in FIG. 11 based on the shift difference thrust.

  In step S109, the CVT control unit 20 calculates a line pressure solenoid command value from the map shown in FIG. 12 based on the target line pressure.

  In step S110, the CVT control unit 20 controls the solenoid 33 of the regulator valve 32 based on the line pressure solenoid command value to adjust the line pressure.

  In step S111, the CVT control unit 20 calculates a target primary pulley pressure based on the basic primary pulley thrust.

  In step S112, the CVT control unit 20 calculates a primary pulley pressure solenoid command value from the map shown in FIG. 13 based on the target primary pulley pressure.

  In step S113, the CVT control unit 20 controls the solenoid 31 of the pressure reducing valve 30 based on the primary pulley pressure solenoid command value to adjust the primary pulley pressure.

  In step S114, the CVT control unit 20 calculates a target secondary pulley pressure based on the basic secondary pulley thrust.

  In step S115, the CVT control unit 20 calculates a secondary pulley pressure solenoid command value from the map shown in FIG. 14 based on the target secondary pulley pressure.

  In step S116, the CVT control unit 20 controls the solenoid 35 of the pressure reducing valve 34 based on the secondary pulley pressure solenoid command value to adjust the secondary pulley pressure.

  In step S117, the CVT control unit 20 detects the primary pulley rotation speed based on the signal from the primary pulley rotation speed sensor 24.

  In step S118, the CVT control unit 20 detects the secondary pulley rotational speed based on the signal from the secondary pulley rotational speed sensor 25.

  In step S119, the CVT control unit 20 calculates the actual gear ratio by dividing the primary pulley rotation speed by the secondary pulley rotation speed (step S119 constitutes a gear ratio calculation means).

  In step S120, the CVT control unit 20 calculates the contact radius between the secondary pulley 11 and the chain 12 based on the actual gear ratio and the secondary pulley rotational speed.

  In step S121, the CVT control unit 20 calculates the stroke amount of the movable tooth 40. Specifically, the CVT control unit 20 is a contact radius between the secondary pulley 11 and the chain 12 when the meshing groove 12a of the chain 12 becomes the first gear ratio (predetermined gear ratio) that meshes with the movable teeth 40. A deviation between the predetermined radius and the contact radius between the secondary pulley 11 and the chain 12 calculated in step S120 is calculated. The stroke amount is zero or more when the meshing groove 12a of the chain 12 and the movable tooth 40 are meshed, and is smaller than zero when the meshing groove 12a of the chain 12 and the movable tooth 40 are not meshed. Become.

  In step S122, the CVT control unit 20 determines whether or not the stroke amount is equal to or greater than zero (step S122 constitutes a meshing determination unit). The process ends the control when the stroke amount is smaller than zero, and proceeds to step S123 when the stroke amount is zero or more. When the stroke amount is greater than or equal to zero, the elastic force of the spring 41 acts on the chain 12 on the secondary pulley 11 side in addition to the clamping force by the hydraulic pressure supplied to the secondary pulley cylinder chamber 11c. The elastic force by the spring 41 is a force that prevents shifting to the High side. The elastic force by the spring 41 increases as the stroke amount increases.

  In step S123, the CVT control unit 20 calculates the secondary pulley thrust reduction amount from the map shown in FIG. 15 based on the stroke amount. The secondary pulley thrust reduction amount increases as the stroke amount increases, and is calculated so as to reduce the tension of the chain 12 that increases on the secondary pulley 11 side by the elastic force of the spring 41. As a result, even when the meshing groove 12a of the chain 12 meshes with the movable tooth 40, the gear can be shifted without increasing the primary pulley pressure, and the gear can be smoothly shifted.

  In step S124, the CVT control unit 20 subtracts the secondary pulley thrust reduction amount from the basic secondary pulley thrust to calculate a reduced basic secondary pulley thrust.

  In step S125, the CVT control unit 20 determines whether the post-reduction basic secondary pulley thrust is equal to or greater than the minimum secondary pulley thrust. The process proceeds to step S127 when the reduced basic secondary pulley thrust is equal to or greater than the minimum secondary pulley thrust, and proceeds to step S126 when the reduced basic secondary pulley thrust is smaller than the minimum secondary pulley thrust.

  In step S126, the CVT control unit 20 sets the minimum secondary pulley thrust as the reduced basic secondary pulley thrust.

  In step S127, the CVT control unit 20 sets the reduced basic secondary pulley thrust as the basic secondary pulley thrust. Here, the current basic secondary pulley thrust is overwritten with the reduced basic secondary pulley thrust.

  In step S128, the CVT control unit 20 calculates a target secondary pulley pressure based on the basic secondary pulley thrust set in step S127.

  In step S129, the CVT control unit 20 calculates a secondary pulley pressure solenoid command value from the map shown in FIG. 14 based on the target secondary pulley pressure.

  In step S130, the CVT control unit 20 controls the solenoid 35 of the pressure reducing valve 34 based on the secondary pulley pressure solenoid command value to regulate the secondary pulley pressure (step S130 constitutes a hydraulic control means). When the basic secondary pulley thrust is overwritten in step S128, the secondary pulley pressure is adjusted again according to the value.

  In step S131, the CVT control unit 20 calculates a slip ratio based on the actual gear ratio and the target gear ratio (step S131 constitutes a deviation calculating means). The slip ratio is a deviation between the actual gear ratio and the target gear ratio. When slippage occurs in the secondary pulley 11, the rotational speed of the primary pulley 10 becomes higher than the rotational speed of the secondary pulley 11, so that the actual speed ratio becomes larger than the target speed ratio.

  In step S132, the CVT control unit 20 determines whether the slip ratio is equal to or less than a predetermined value. The predetermined value is a value for determining whether or not the meshing groove 12a of the chain 12 and the movable tooth 40 are meshed, and is set in advance by an experiment or the like. For example, when it is determined in step S122 that the stroke amount is zero or more and the engagement groove 12a of the chain 12 and the movable tooth 40 are engaged, the slip ratio is greater than a predetermined value. There is a possibility that an abnormality occurs in at least one of the movable teeth 40, the spring 41, and the chain 12, and the engagement groove 12a of the chain 12 and the movable teeth 40 may not be engaged. In step S132, when the slip ratio is greater than the predetermined value, the CVT control unit 20 determines that an abnormality has occurred in at least one of the movable teeth 40, the spring 41, and the chain 12 (step S132 is abnormal). A determination means is configured.). The process ends this control when the slip ratio is equal to or less than the predetermined value, and proceeds to step S133 when the slip ratio is larger than the predetermined value.

  In step S133, the CVT control unit 20 applies an abnormality when an abnormality occurs in at least one of the movable teeth 40, the spring 41, and the chain 12, and the engagement groove 12a of the chain 12 and the movable teeth 40 are not engaged. Hour basic secondary pulley thrust is set as basic secondary pulley thrust. Here, the basic secondary pulley thrust set in step S127 is further overwritten.

  In step S134, the CVT control unit 20 calculates a target secondary pulley pressure based on the basic secondary pulley thrust.

  In step S135, the CVT control unit 20 calculates a secondary pulley pressure solenoid command value from the map shown in FIG. 14 based on the target secondary pulley pressure.

  In step S136, the CVT control unit 20 controls the solenoid 35 of the pressure reducing valve 34 based on the secondary pulley pressure solenoid command value to adjust the secondary pulley pressure. Here, when the basic secondary pulley thrust is overwritten in step S133, the secondary pulley pressure is adjusted again according to the value.

  In step S137, the CVT control unit 20 sets the failure determination flag to “1”. The failure determination flag is set to “0” as an initial value.

  If it is determined in step S100 that the failure determination flag is “1”, in step S138, the CVT control unit 20 determines that the other abnormality determination flag, for example, the gear ratio is the meshing groove 12a of the chain 12 and the movable teeth 40. Whether or not an abnormality has occurred in the continuously variable transmission 5 is determined based on a flag indicating that slip has occurred at a gear ratio that is lower than the first gear ratio. The process proceeds to step S139 if another abnormality has occurred in the continuously variable transmission 5, and proceeds to step S140 if no other abnormality has occurred in the continuously variable transmission 5.

  In step S139, the CVT control unit 20 executes the safe mode. In the safe mode, for example, when the vehicle is traveling, the gear ratio is maintained at the current gear ratio, and after the vehicle stops, the gear ratio is limited to the lowest level.

  In step S140, the CVT control unit 20 limits the gear ratio so that the meshing groove 12a of the chain 12 and the movable tooth 40 do not mesh (step S140 constitutes a limiting means). Further, the CVT control unit 20 notifies the driver by turning on a warning lamp indicating that an abnormality has occurred in any one of the movable teeth 40, the spring 41, and the chain 12 (step S140 is a notification means). Configure.)

  The effect of 1st Embodiment of this invention is demonstrated.

  If it is determined that the meshing groove 12a of the chain 12 is not meshed with the movable tooth 40 after the actual gear ratio becomes the first gear ratio with which the meshing groove 12a of the chain 12 meshes with the movable tooth 40, the movable tooth 40 It is determined that an abnormality has occurred in at least one of the spring 41 and the chain 12. Accordingly, it is possible to detect the occurrence of abnormality in the movable teeth 40, the spring 41, and the chain 12, and it is possible to detect a state where the meshing groove 12a and the movable teeth 40 are not normally meshed (corresponding to claims 1 and 7). Effect).

  The actual gear ratio becomes the first gear ratio in which the meshing groove 12a of the chain 12 meshes with the movable teeth 40, and after the stroke amount becomes zero or more, the slip ratio between the actual gear ratio and the target gear ratio is larger than a predetermined value. If it is determined that the engagement groove 12a of the chain 12 is not engaged with the movable tooth 40, it is determined that an abnormality has occurred in at least one of the movable tooth 40, the spring 41, and the chain 12. Thereby, it is possible to detect the occurrence of an abnormality in the movable tooth 40, the spring 41, and the chain 12 without using a hydraulic pressure sensor (effect corresponding to claim 3).

  When it is determined that an abnormality has occurred in at least one of the movable teeth 40, the spring 41, and the chain 12, the gear ratio is limited to a gear ratio at which the meshing groove 12a of the chain 12 and the movable teeth 40 do not mesh. Thereby, it can suppress that the state of the movable tooth 40 in which abnormality generate | occur | produced, the spring 41, and the chain 12 deteriorates further (the effect corresponding to Claim 4).

  When it is determined that an abnormality has occurred in at least one of the movable teeth 40, the spring 41, and the chain 12, a warning lamp is turned on. Thus, it is possible to notify the driver that an abnormality has occurred (effect corresponding to claim 6).

  Next, a second embodiment of the present invention will be described.

  In the second embodiment, the hydraulic control unit 100 and the CVT control unit 20 are different from the first embodiment. Here, the hydraulic control unit 100 and the CVT control unit 20 will be mainly described with reference to FIG. FIG. 16 is a conceptual diagram of the hydraulic control unit 100 and the CVT control unit 20. About the same structure as 1st Embodiment, the code | symbol same as the code | symbol of 1st Embodiment is attached | subjected and description here is abbreviate | omitted.

  The hydraulic control unit 100 includes a regulator valve 32, a shift control valve 37, a pressure reducing valve 30, and a pressure reducing valve 34.

  The shift control valve 37 is a control valve that controls the primary pulley pressure in the primary pulley cylinder chamber 10c to be a desired target pressure. The shift control valve 37 is connected to a servo link 70 constituting a mechanical feedback mechanism, is driven by a step motor 71 connected to one end of the servo link 70, and is connected to the other end of the servo link 70. The groove width, that is, feedback of the actual gear ratio is received from the movable conical plate 10a. The speed change control valve 37 adjusts the primary pulley pressure so as to achieve the target speed ratio commanded at the drive position of the step motor 71 by sucking and discharging the hydraulic pressure to the primary pulley cylinder chamber 10c by the displacement of the spool 37a. When the shift is completed, the spool 37a is held in the valve closing position in response to the displacement from the servo link 70.

  The CVT control unit 20 includes a signal from the inhibitor switch 22, a signal from the accelerator pedal sensor 23, a signal from the primary pulley rotational speed sensor 24, a signal from the secondary pulley rotational speed sensor 25, a signal from the brake pedal sensor 26, a primary Based on the signal from the pulley pressure sensor 27, the signal from the secondary pulley pressure sensor 28, etc., the gear ratio and the like are controlled.

  Next, the shift control in the present embodiment will be described with reference to the flowcharts of FIGS.

  In step S200, the CVT control unit 20 determines whether or not the failure determination flag is “1”. The process proceeds to step S230 if the failure determination flag is “1”, and proceeds to step S201 if the failure determination flag is “0”.

  In step S201, the CVT control unit 20 calculates a target gear ratio from the vehicle speed, the engine speed, the throttle opening, and the position of the select lever. The engine speed is detected based on a signal from the engine speed sensor 29 (step S201 constitutes a target gear ratio calculation unit).

  In step S202, the CVT control unit 20 calculates the step motor position from the map shown in FIG. 20 based on the target gear ratio.

  In step S203, the CVT control unit 20 drives the step motor 71 based on the calculated step motor position. Thereby, the shift control valve 37 is controlled.

  In step S <b> 204, the CVT control unit 20 receives input torque information from the engine control unit 21.

  In step S205, the CVT control unit 20 calculates a minimum thrust limit value, a basic primary pulley thrust, and a basic secondary pulley thrust based on the target gear ratio and the input torque.

  In step S206, the CVT control unit 20 calculates a target line pressure based on the basic primary pulley thrust and the basic secondary pulley thrust.

  In step S207, the CVT control unit 20 calculates a line pressure solenoid command value from the map shown in FIG. 12 based on the target line pressure.

  In step S208, the CVT control unit 20 controls the solenoid 33 of the regulator valve 32 based on the line pressure solenoid command value to adjust the line pressure.

  In step S209, the CVT control unit 20 calculates the target primary pulley pressure and the target secondary pulley pressure by thrust distribution control based on the basic secondary pulley thrust and the minimum thrust limit value.

  In step S210, the CVT control unit 20 calculates a primary pulley pressure solenoid command value from the map shown in FIG. 13 based on the target primary pulley pressure.

  In step S211, the CVT control unit 20 controls the solenoid 31 of the pressure reducing valve 30 based on the primary pulley pressure solenoid command value to adjust the primary pulley pressure supplied to the speed change control valve 37.

  In step S212, the CVT control unit 20 detects the primary pulley rotational speed based on the signal from the primary pulley rotational speed sensor 24.

  In step S213, the CVT control unit 20 detects the secondary pulley rotation speed based on the signal from the secondary pulley rotation speed sensor 25.

  In step S214, the CVT control unit 20 calculates the actual gear ratio by dividing the primary pulley rotational speed by the secondary pulley rotational speed (step S214 constitutes a gear ratio calculating means).

  In step S215, the CVT control unit 20 calculates the contact radius between the secondary pulley 11 and the chain 12 based on the actual gear ratio and the secondary pulley rotational speed.

  In step S216, the CVT control unit 20 calculates the stroke amount of the movable tooth 40. The method for calculating the stroke amount is the same as that in step S121 in the first embodiment.

  In step S217, the CVT control unit 20 determines whether or not the stroke amount is equal to or greater than zero (step S217 constitutes a meshing determination unit). The process proceeds to step S227 when the stroke amount is smaller than zero, and proceeds to step S218 when the stroke amount is zero or more.

  In step S218, the CVT control unit 20 calculates the secondary pulley thrust reduction amount from the map shown in FIG. 15 based on the stroke amount.

  In step S219, the CVT control unit 20 subtracts the secondary pulley thrust reduction amount from the basic secondary pulley thrust to calculate a reduced basic secondary pulley thrust.

  In step S220, the CVT control unit 20 determines whether the post-reduction basic secondary pulley thrust is equal to or greater than the minimum secondary pulley thrust. The process proceeds to step S222 when the reduced basic secondary pulley thrust is equal to or greater than the minimum secondary pulley thrust, and proceeds to step S221 when the reduced basic secondary pulley thrust is smaller than the minimum secondary pulley thrust.

  In step S221, the CVT control unit 20 sets the minimum secondary pulley thrust as the post-reduction basic secondary pulley thrust.

  In step S222, the CVT control unit 20 sets the reduced basic secondary pulley thrust as the basic secondary pulley thrust. Here, the basic secondary pulley thrust calculated in step S205 is overwritten.

  In step S223, the CVT control unit 20 calculates a slip ratio based on the actual gear ratio and the target gear ratio (step S223 constitutes a deviation calculating means). The calculation method of the slip ratio is the same method as step S131 of the first embodiment.

  In step S224, the CVT control unit 20 determines whether or not the slip ratio is equal to or less than a predetermined value (step S224 constitutes an abnormality determination unit). The process proceeds to step S227 when the slip ratio is equal to or less than the predetermined value, and proceeds to step S225 when the slip ratio is larger than the predetermined value.

  In step S225, the CVT control unit 20 sets the failure determination flag to “1”.

  In step S226, the CVT control unit 20 applies an abnormality when an abnormality occurs in at least one of the movable teeth 40, the spring 41, and the chain 12, and the engagement groove 12a of the chain 12 and the movable teeth 40 are not engaged. Hour basic secondary pulley thrust is set as basic secondary pulley thrust. Here, the basic secondary pulley thrust set in step S222 is further overwritten.

  In step S227, the CVT control unit 20 calculates a target secondary pulley pressure. Specifically, when the stroke amount is smaller than zero in step S217, the CVT control unit 20 sets the target secondary pulley pressure calculated in step S209 as it is as the target secondary pulley pressure. When it is determined in step S224 that the slip ratio is equal to or less than the predetermined value, the CVT control unit 20 calculates the target secondary pulley pressure based on the basic secondary pulley thrust set in step S222. Further, when it is determined in step S224 that the slip ratio is larger than the predetermined value, the CVT control unit 20 calculates the target secondary pulley pressure based on the basic secondary pulley thrust set in step S226.

  In step S228, the CVT control unit 20 calculates a secondary pulley pressure solenoid command value from the map shown in FIG. 14 based on the target secondary pulley pressure.

  In step S229, the CVT control unit 20 controls the solenoid 35 of the pressure reducing valve 34 based on the secondary pulley pressure solenoid command value, and regulates the secondary pulley pressure (step S229 constitutes a hydraulic pressure control means).

  The control after step S200 is determined that the failure determination flag is “1” is the same as the control at step S138 to step S140 in the first embodiment, and therefore will be described here. Is omitted.

  The effect of 2nd Embodiment of this invention is demonstrated.

  Also in the continuously variable transmission 5 having the step motor 71 and the shift control valve 37, the same effect as in the first embodiment can be obtained.

  Next, a third embodiment of the present invention will be described.

  The third embodiment differs from the second embodiment in shift control. Shift control in the present embodiment will be described with reference to FIGS.

  Since the control of step S300 to step S311 is the same as the control of step S200 to step S211 of the second embodiment, description thereof is omitted here.

  In step S312, the CVT control unit 20 detects the actual primary pulley pressure based on the signal from the primary pulley pressure sensor 27.

  In step S313, the CVT control unit 20 determines whether the actual primary pulley pressure and the target primary pulley pressure are equal. The process proceeds to step S323 when the actual primary pulley pressure and the target primary pulley pressure are equal, and proceeds to step S314 when the actual primary pulley pressure and the target primary pulley pressure are not equal.

  In step S314, the CVT control unit 20 determines whether the actual primary pulley pressure is lower than the target primary pulley pressure. The process proceeds to step S315 when the actual primary pulley pressure is higher than the target primary pulley pressure, and proceeds to step S323 when the actual primary pulley pressure is lower than the target primary pulley pressure.

  In step S315, the CVT control unit 20 detects the primary pulley rotation speed based on the signal from the primary pulley rotation speed sensor 24.

  In step S316, the CVT control unit 20 detects the secondary pulley rotational speed based on the signal from the secondary pulley rotational speed sensor 25.

  In step S317, the CVT control unit 20 calculates the actual gear ratio by dividing the primary pulley rotational speed by the secondary pulley rotational speed (step S317 constitutes the gear ratio calculating means).

  In step S318, the CVT control unit 20 determines whether or not the actual speed ratio is equal to or less than the second speed ratio (predetermined speed ratio). The second gear ratio is a gear ratio at which it can be determined that the meshing groove 12a of the chain 12 meshes with the movable tooth 40 and the actual primary pulley pressure is equal to or higher than a predetermined hydraulic pressure. The predetermined hydraulic pressure is a pressure at which it can be determined that the chain 12 is urged radially outward of the output shaft 13 by the elastic force of the spring 41, and is set in consideration of an error of a sensor or the like, and as the input torque increases. growing. The predetermined oil pressure is a pressure that is 110% higher than the target primary pulley pressure. The process proceeds to step S319 when the actual speed ratio is equal to or lower than the second speed ratio, and proceeds to step S323 when the actual speed ratio is greater than the second speed ratio.

  In step S319, the CVT control unit 20 determines whether or not the actual primary pulley pressure is equal to or higher than a predetermined hydraulic pressure (step S319 constitutes a meshing determination unit). The predetermined hydraulic pressure is the same value as the predetermined hydraulic pressure in step S318. Here, it is determined whether or not the actual primary pulley pressure is actually equal to or higher than a predetermined hydraulic pressure. If there is no abnormality in any of the movable teeth 40, the spring 41, and the chain 12, the urging force of the movable teeth 40 acts on the chain 12, and the actual primary pulley pressure increases accordingly and becomes a predetermined value or more. ing. The process proceeds to step S320 when the actual primary pulley pressure is equal to or higher than the predetermined oil pressure, and proceeds to step S321 when the actual primary pulley pressure is lower than the predetermined oil pressure.

  In step S320, the CVT control unit 20 sets the secondary pulley reduction instruction flag to “1”. The secondary pulley reduction instruction flag is set to “0” as an initial value.

  In step S321, the CVT control unit 20 determines whether or not the secondary pulley reduction instruction flag is “1”. The process proceeds to step S324 when the secondary pulley reduction instruction flag is “1”, and proceeds to step S323 when the secondary pulley reduction instruction flag is “0”.

  In step S322, the CVT control unit 20 sets the failure determination flag to “1”. The failure determination flag is set to “0” as an initial value.

  In step S323, the CVT control unit 20 determines whether or not the secondary pulley reduction instruction flag is “1”. The process proceeds to step S324 when the secondary pulley reduction instruction flag is “1”, and proceeds to step S336 when the secondary pulley reduction instruction flag is “0”.

  In step S324, the CVT control unit 20 determines whether or not a secondary pulley pressure reduction learning flag for an estimated input torque, which will be described in detail later, is “1”. The process proceeds to step S325 when the secondary pulley pressure reduction learning flag is “1”, and proceeds to step S326 when the secondary pulley pressure reduction learning flag is “0”.

  In step S325, the CVT control unit 20 sets a learning value, which will be described later in detail, as a target secondary pulley pressure based on the actual gear ratio. Here, the current target secondary pulley pressure is overwritten by the learned value.

  In step S326, the CVT control unit 20 calculates the deviation between the actual primary pulley pressure and the target primary pulley pressure.

  In step S327, the CVT control unit 20 calculates the secondary pulley pressure reduction amount from the map shown in FIG. 24 based on the deviation. The amount of secondary pulley pressure reduction increases as the deviation increases. The secondary pulley pressure reduction amount is calculated so as to reduce the tension of the chain 12 that increases on the secondary pulley 11 side by the elastic force of the spring 41. Thereby, even when the meshing groove 12a of the chain 12 meshes with the movable tooth 40, it becomes possible to perform a shift without increasing the primary pulley pressure.

  In step S328, the CVT control unit 20 subtracts the secondary pulley pressure reduction amount from the target secondary pulley pressure to calculate a post-reduction secondary pulley pressure.

  In step S329, the CVT control unit 20 calculates the minimum secondary pulley pressure based on the basic secondary pulley thrust and the minimum thrust limit value.

  In step S330, the CVT control unit 20 determines whether the post-reduction secondary pulley pressure is greater than or equal to the minimum secondary pulley pressure. The process proceeds to step S331 when the post-reduction secondary pulley pressure is equal to or greater than the minimum secondary pulley pressure, and proceeds to step S332 when the post-reduction secondary pulley pressure is lower than the minimum secondary pulley pressure.

  In step S331, the CVT control unit 20 sets the post-reduction secondary pulley pressure as the target secondary pulley pressure. Here, the current target secondary pulley pressure is overwritten by the post-reduction secondary pulley pressure.

  In step S332, the CVT control unit 20 sets the minimum secondary pulley pressure command value as the target secondary pulley pressure. Here, the current target secondary pulley pressure is overwritten by the minimum secondary pulley pressure command value.

  Note that the target secondary pulley pressure overwritten in steps S331 and S332 is temporarily stored in the CVT control unit 20 in accordance with each actual gear ratio.

  In step S333, the CVT control unit 20 determines whether or not the actual gear ratio has reached the highest level. The process proceeds to step S334 when the actual gear ratio is the highest, and proceeds to step S336 when the actual gear ratio is not the highest.

  In step S334, the CVT control unit 20 stores the target secondary pulley pressure stored for the actual gear ratio as a learned value. Note that the temporarily stored target secondary pulley pressure is deleted. Further, the target secondary pulley pressure that is temporarily stored is also deleted when the actual gear ratio is changed from the previous control to the low gear ratio.

  In step S335, the CVT control unit 20 sets the secondary pulley pressure learning flag to “1”. The secondary pulley pressure learning flag is set to “0” as an initial value. The secondary pulley pressure learning flag is set for each input torque.

  In step S336, the CVT control unit 20 calculates a secondary pulley pressure solenoid command value from the map shown in FIG. 14 based on the target secondary pulley pressure.

  In step S337, the CVT control unit 20 controls the solenoid 35 of the pressure reducing valve 34 based on the secondary pulley pressure solenoid command value, and regulates the secondary pulley pressure (step S337 constitutes a hydraulic control means).

  The control after step S <b> 300 determines that the failure determination flag is “1” is the same as the control at step S <b> 138 to step S <b> 340 in the first embodiment, and will be described here. Is omitted.

  The effect of the third embodiment of the present invention will be described.

  Even if the actual transmission gear ratio becomes the second transmission gear ratio in which the meshing groove 12a of the chain 12 meshes with the movable tooth 40, the actual primary pulley pressure is greater than the predetermined hydraulic pressure when the meshing groove 12a of the chain 12 meshes with the movable tooth 40. When it is low, it is determined that the meshing groove 12 a of the chain 12 is not meshed with the movable tooth 40. By determining the occurrence of an abnormality in the movable tooth 40, the spring 41, and the chain 12 based on the actual primary pulley pressure that is increased when the meshing groove 12a of the chain 12 and the movable tooth 40 are engaged, the movable tooth 40, the spring 41, The occurrence of an abnormality in the chain 12 can be detected (effect corresponding to claim 2).

  The embodiment of the present invention has been described above. However, the above embodiment only shows a part of application examples of the present invention, and the technical scope of the present invention is limited to the specific configuration of the above embodiment. Absent.

  In the above embodiment, it is determined whether the meshing groove 12a of the chain 12 and the movable tooth 40 are meshed based on the stroke amount or the primary pulley pressure, but the position of the movable conical plate 11a of the secondary pulley 11 and the chain 12 You may determine based on the sound, vibration, etc. which are generated when the movable tooth 40 hits.

  In the first and second embodiments, when the stroke amount becomes zero or more, the secondary pulley thrust reduction amount is calculated and the secondary pulley pressure is lowered. The secondary pulley thrust reduction amount may be calculated to lower the secondary pulley pressure.

  In the above embodiment, an abnormality occurs in at least one of the movable teeth 40, the spring 41, or the chain 12 based on the slip ratio or the primary pulley pressure, and the engagement groove 12a of the chain 12 and the movable teeth 40 are not engaged. However, it may be determined based on hydraulic pressure, oil vibration, sound, or the like.

  In the above embodiment, the engine 1 is used as a power source, but a motor or an engine and a motor may be used as the power source.

  In the above embodiment, the chain 12 is used as the power transmission part (band body) of the continuously variable transmission 5. However, a power transmission part that transmits power on the pull side, for example, a rubber belt that can mesh with the movable teeth 40 may be used. Good.

  In the above embodiment, the movable teeth 40 are provided on the secondary pulley 11, but the movable teeth 40 may be provided on the primary pulley 10.

  In the above embodiment, the gear ratio is limited when any one of the movable teeth 40, the spring 41, and the chain 12 is abnormal. The pulley pressure may not be lowered. Thereby, it can suppress that a slip generate | occur | produces between the chain 12 and the secondary pulley 11 (effect corresponding to Claim 5).

1 Engine (Power source)
5 Continuously variable transmission 10 Primary pulley (first pulley)
11 Secondary pulley (second pulley)
12 Chain
12a Meshing groove (groove)
20 CVT control unit (hydraulic control means, meshing judgment means, abnormality judgment means, target gear ratio calculation means, actual gear ratio calculation means, deviation calculation means, restriction means, notification means)
27 Primary pulley pressure sensor (hydraulic pressure detecting means)
36 Oil pump 40 Movable teeth 41 Spring (biasing means)

Claims (7)

A first pulley having a first movable conical plate that moves in the axial direction in accordance with the hydraulic pressure supplied to and discharged from the first fixed conical plate and the first oil chamber;
A second fixed conical plate, a second movable conical plate that moves in the axial direction according to the hydraulic pressure supplied to and discharged from the second oil chamber, and a second pulley having movable teeth that are movable in the radial direction of the shaft portion;
A groove that is wound between the first pulley and the second pulley to transmit power between the first pulley and the second pulley and engage with the movable teeth is formed on the inner peripheral surface. An annular belt,
A continuously variable transmission comprising a biasing means that biases the movable teeth radially outward of the shaft portion;
Meshing judging means for judging whether or not the groove meshes with the movable tooth;
If the gear ratio is a predetermined gear ratio at which the groove meshes with the movable tooth, and the mesh determination means determines that the groove does not mesh with the movable tooth, the movable tooth, the biasing force And an abnormality determining means for determining that an abnormality has occurred in at least one of the belt bodies. The continuously variable transmission according to claim 1,
A hydraulic pressure detecting means for detecting the hydraulic pressure of the first oil chamber;
The meshing determination means is configured so that the gear ratio becomes the predetermined gear ratio, and the hydraulic pressure of the first oil chamber detected by the hydraulic pressure detection means is a hydraulic pressure when the groove and the movable tooth mesh with each other. A continuously variable transmission that determines that the groove is not meshed with the movable tooth when the hydraulic pressure is lower than a predetermined hydraulic pressure calculated based on an input torque input to the first pulley. The continuously variable transmission according to claim 1,
Target gear ratio calculating means for calculating the target gear ratio;
Gear ratio calculating means for calculating an actual gear ratio;
Deviation calculating means for calculating a deviation between the actual gear ratio and the target gear ratio;
The meshing determination means determines that the groove is not meshed with the movable tooth when the actual gear ratio is the predetermined gear ratio and the deviation is larger than a predetermined value. Machine. The continuously variable transmission according to claim 1 or 2 ,
When the abnormality determining means determines that an abnormality has occurred in at least one of the movable teeth, the urging means, and the belt, the gear ratio is meshed with the movable teeth. A continuously variable transmission, characterized by comprising limiting means for limiting the transmission ratio to not. The continuously variable transmission according to claim 1 or 2 ,
A hydraulic control means for reducing the hydraulic pressure of the second oil chamber when the gear ratio becomes the predetermined gear ratio;
The hydraulic pressure control unit determines the hydraulic pressure of the second oil chamber when it is determined by the abnormality determination unit that an abnormality has occurred in at least one of the movable teeth, the biasing unit, and the belt. A continuously variable transmission characterized by not lowering the speed. A continuously variable transmission according to any one of claims 1 to 5,
And a notification means for notifying the occurrence of an abnormality when the abnormality determination means determines that an abnormality has occurred in at least one of the movable tooth, the biasing means, and the belt. Continuously variable transmission. A first pulley having a first movable conical plate that moves in the axial direction in accordance with the hydraulic pressure supplied to and discharged from the first fixed conical plate and the first oil chamber;
A second fixed conical plate, a second movable conical plate that moves in the axial direction according to the hydraulic pressure supplied to and discharged from the second oil chamber, and a second pulley having movable teeth that are movable in the radial direction of the shaft portion;
A groove that is wound between the first pulley and the second pulley to transmit power between the first pulley and the second pulley and engage with the movable teeth is formed on the inner peripheral surface. An annular belt,
A control method for controlling a continuously variable transmission comprising a biasing means for biasing the movable teeth radially outward of the shaft portion;
Determining whether the groove meshes with the movable tooth;
When it is determined that the gear ratio is a predetermined gear ratio at which the groove meshes with the movable tooth and the groove does not mesh with the movable tooth, the movable tooth, the biasing means, and the belt body And determining that an abnormality has occurred in at least one of the control methods.

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