JP2012163181A - Transmission control device of conical friction wheel ring type continuously variable transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve a problem that the accuracy of transmission control by an inclined angle of a ring is not sufficient because there are error and fluctuation in the detected stair angle of the ring by seer angle control detecting the inclined angle of the ring.SOLUTION: The steer angle of the ring is calculated from the rotational frequency of the ring obtained from the rotational frequency of an output side friction wheel and the position of the ring in an axial direction and the position change of the ring in the axial direction, the detected steer angle of the ring of steer angle control is corrected by the calculated steer angle.

Description

  The present invention relates to a conical friction wheel ring type continuously variable transmission (cone ring type CVT), which relates to a speed change control device that changes speed by tilting the ring, and is an engine (internal combustion engine) or an electric motor (electric vehicle) The present invention also relates to a transmission control device for a cone ring CVT that is suitable for being mounted on an automobile using an electric motor (hybrid vehicle) as a drive source.

  The cone-ring type CVT has a conical input side friction wheel and an output side friction wheel arranged so that the large diameter side and the small diameter side are reversed on axes parallel to each other, and one of these friction wheels ( For example, a ring that is sandwiched between the opposing inclined surfaces of the two friction wheels so as to surround the input friction wheel), and the ring is moved in the axial direction to change the contact position of the two friction wheels. Shifted to a stage.

  2. Description of the Related Art Conventionally, there has been proposed a speed change control device in which the ring moves in the axial direction based on the angle (steer angle) by swinging (steering) the rotation plane of the ring with respect to the axis (patent). Reference 1 and 2).

  The speed change operation member of the cone ring type CVT of Patent Documents 1 and 2 has an adjustment bridge that surrounds one side of the ring by about 180 degrees, and guide rollers disposed at both ends of the adjustment bridge. The ring is sandwiched, and the ring is supported so as to be movable in the rotational direction. The adjustment bridge is movably supported by a pair of guide rods extending along a cone inclination angle of the conical friction wheel (input-side friction wheel), and a cage having the guide rods includes the input side and An actuator such as an electric motor swings the retainer at a predetermined angle (stair angle), supported on a pivot shaft that passes through the axis of both friction wheels on the output side and is disposed on a line orthogonal to the axis. ), The rotation plane of the ring becomes the steer angle with respect to the axis of the friction wheel, and the ring contacts the input side and the output side friction wheel at the steer angle. Then, the ring automatically moves in the axial direction by the rotation of the ring in the steering angle plane, and the speed is changed by changing the contact position with both friction wheels.

JP-A-10-331935 Special table 2007-515607 gazette

  In the cone ring type CVT shift control device, a required steer angle is output to an actuator so that the ring is directed to a target gear ratio (required ratio), and the actuator has a cage, that is, a ring, so that the required steer angle is achieved. The rotation plane is controlled to a predetermined swing angle to control the shift.

  At this time, even if the ring swing position (steer angle) is detected by a sensor or the steering angle is controlled by an output pulse of an actuator such as a stepping motor, the error of the steer angle and the initial position The target gear ratio (ratio) cannot be tracked due to variations in the (steer angle 0 position). For example, in vehicle control, the optimal engine speed is not aimed at and the best fuel efficiency is achieved. The traveling control along the characteristic point cannot be performed.

  Further, since the steering angle varies, the required speed cannot be achieved. For example, the drivability such as causing a pull-in feeling at the time of kick-down operation is deteriorated, or the ring is under-driven (U / D) before stopping. ) There is a possibility that the fail-safe may be affected.

  Therefore, the present invention calculates the steer angle of the ring from the movement change amount of the axial position of the ring and the ring rotation speed, thereby correcting the steer angle control by the actuator, thereby solving the above-mentioned problem. It is an object of the present invention to provide a shift control apparatus.

The present invention relates to a conical input side friction wheel (2) and an output side friction wheel (3) arranged so that the large diameter side and the small diameter side are reversed on mutually parallel axes, and both the friction wheels. The ring (5) sandwiched between the opposing inclined surfaces of the two friction wheels so as to surround one of the two wheels, and the steering angle with respect to the axis of the ring is operated to move the ring in the axial direction as the two friction wheels rotate. In the transmission control device (11) of the conical friction wheel ring type continuously variable transmission (1), comprising a transmission operation mechanism (12) and an actuator (6) for operating the transmission operation mechanism.
In the steer angle control for controlling the actuator (6) so that the detected steer angle (θ ′) of the ring (5) becomes a required steer angle, the detected steer angle is changed in the axial position of the ring. (Δx) and the ring steer angle (θ) calculated from the ring rotation speed (V).
The present invention resides in a shift control device for a conical friction wheel ring type continuously variable transmission.

  The detected steering angle of the ring may be detected by a sensor such as an encoder, or the actuator may be a stepping motor and the amount of movement of the actuator may be detected by an input pulse thereof.

  The corrected value is learned and stored in a map, and the actuator (6) is controlled based on the map.

  The detected steering angle (θ ′) of the ring (5) is an angle detected by a sensor disposed in the speed change operation mechanism (12).

  The axial position of the ring is an axial position detected by a sensor disposed in the speed change operation mechanism (12).

  The axial position of the ring is calculated based on the rotational speeds (Ni, No) of the input side friction wheel (2) and the output side friction wheel (3).

  The calculated axial position of the ring is not limited only to the actual gear ratio based on the rotational speeds of the input friction wheel and the output friction wheel, but is estimated based on the input torque, the temperature of the traction oil, and the like. You may consider the slip ratio. Further, the ring axial position by the sensor may be corrected and mapped by the ring axial position calculated from the actual gear ratio.

  The rotational speed (V) of the ring is calculated from the rotational speed of the input side friction wheel (2) or the output side friction wheel (3) and the axial position (x) of the ring (5).

  The learning map is a map that takes into account the spin torque acting on the ring.

  In addition, although the code | symbol in the said parenthesis is for contrast with drawing, it does not have any influence on description of a claim by this.

  According to the first aspect of the present invention, since the detected steering angle is corrected based on the actual steering angle of the ring calculated from the change in the axial position of the ring and the rotational speed of the ring, the steering angle (tilt angle) of the ring is corrected. In the shift control device that performs shift control by means of an engine, the error in the shift position is reduced due to detection steer angle error and variation. For example, when the cone ring CVT is mounted on a vehicle, the engine aims at the point of optimum fuel consumption characteristics. In addition, it is possible to achieve a target shift speed, improve drivability, and reliably return the ring to the maximum U / D position when stopped.

  According to the second aspect of the present invention, since the correction is learned by averaging in a stable state, the detected steer angle is corrected by the learned correction term, and the steer angle of the stable ring is quickly corrected. Shift control can be performed.

  According to the third aspect of the present invention, since the detected steering angle of the ring is detected by a sensor such as an encoder disposed in the speed change operation mechanism, various actuators can be used, and the detection by the sensor can be performed by the above correction. The steer angle can be corrected easily and accurately.

  According to the fourth aspect of the present invention, since the axial position of the ring is detected by the sensor that is disposed in the speed change operation mechanism and measures the axial position of the ring, the axial position of the ring is detected quickly and accurately. be able to.

  According to the fifth aspect of the present invention, since the axial position of the ring is calculated based on the rotational speeds of the input side and output side friction wheels, a sensor for actually measuring the axial position of the ring is not required.

  According to the present invention of claim 6, the rotation speed of the ring is easily calculated from the rotation of the friction wheel such as the output side friction wheel and the radius at the ring contact position of the friction wheel derived from the axial position of the ring. be able to.

  According to the seventh aspect of the present invention, for example, assuming that the slip ratio on the output side is 0, the axial force acting on the cone-ring type CVT is calculated from the output torque, and corrected in consideration of the spin torque acting on the ring. Since the obtained value is stored in the map by learning, the steer angle of the ring can be controlled with higher accuracy.

Schematic which shows the transmission control apparatus of cone ring type CVT. FIG. 3 is an overall model diagram of the transmission control device. The figure which shows the control theoretical formula of a ring. The time chart and flowchart which show the state which carried out error correction of the ring steering angle. The figure which shows error correction | amendment of a ring steer angle. The figure which shows the error correction of the ring steer angle by a spin torque. The figure which shows embodiment changed partially.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In FIG. 1, reference numeral 1 denotes a conical friction wheel ring type continuously variable transmission (cone ring type CVT) that constitutes a transmission mechanism for a vehicle, and is rotatable about two parallel axes supported by a case. The conical input side friction wheel 2 and the output side friction wheel 3 arranged so that the large diameter side and the small diameter side are reversed, and one of these friction wheels (in this embodiment, A ring 5 sandwiched between the inclined surfaces facing each other so as to surround the input side friction wheel 2). The ring 5 is swung (steered) by a shift support mechanism 12 (refer to Patent Document 1 or 2 described above in detail) with a pivot shaft on an axis B orthogonal to the two axes on a plane including the two axes. In the shift operation mechanism, the steering angle is controlled by the shift control actuator 6. The actuator may be an electric linear actuator, a hydraulic cylinder, or a rotary motor, and may be one that can control the rotation angle by an input signal, such as a stepping motor.

  The input side friction wheel 2 is connected to an engine 9 as a drive source via a clutch 7, and the output side friction wheel 3 is connected to a drive wheel 10. The drive source is not limited to the engine, and may be an electric motor or a hybrid system of the engine and the electric motor. The transmission mechanism is not limited to the above-described cone ring type CVT 1 but may be a gear such as a gear. A combination of mechanisms may also be used.

  A control unit (model) 11 for driving and controlling the shift control actuator 6 includes a required ratio (target gear ratio) Rr from the control of the axle, the input rotational speed Ni of the input side friction wheel 2, and the output side friction wheel 3. The output rotational speed No is input, and the input torque Ti calculated from the engine rotational speed, the oil temperature O of the traction oil sealed in the case in which the cone ring type CVT 1 is stored, and the axial position of the ring A certain ring position ratio x and a steering angle θ ′ of the ring are input. In the present embodiment, the ring position ratio x is arranged in the speed change operation mechanism 12 and inputs a signal from a sensor for detecting the axial position of the ring 5. A value obtained from a gear ratio (gear ratio) calculated from Ni and the output rotation speed No may be used. Alternatively, the ring slip ratio may be estimated from the input torque Ti, the input rotational speed Ni, and the temperature O of the traction oil, and the axial position of the ring may be calculated in consideration of the slip ratio in the gear ratio. The steer angle (detected steer angle) θ ′ is disposed in the speed change operation mechanism 12 and receives a signal from a sensor such as an encoder that detects the rotation angle of the pivot shaft on the axis B. For example, it may be a control signal value to the actuator that becomes the operation amount of the shift control actuator 6 such as the number of pulses of the stepping motor.

  Therefore, in the present embodiment, the control unit 11 compares the required ratio Rr with the ring position ratio x, and compares the required steer angle of the ring based on the required ratio with the detected steer angle θ. The position of the actuator 6 is controlled.

  Even if the detected steering angle θ ′ is a signal from an encoder or an output signal value to the shift control actuator 6, there are errors and variations in the initial position (θ ′ = 0). It is difficult to control the steering angle of the ring 5 along the required steering angle with an accurate steering angle.

  FIG. 2 shows a shift control apparatus (model) according to the present invention that solves the above-described problems. In actual travel control, a target ratio (required ratio) is input to the shift control unit 11 such as an ECU from the vehicle side or from a test device in a test. In the speed change control unit 11, the required ratio is compared with the current gear ratio (gear ratio) calculated from the ring position, as shown in FIG.

  Then, the shift control unit 11 drives the shift control actuator 6 by feedback control based on the detected steer angle θ ′ from the steer angle sensor based on the required steer angle calculated by the request ratio and the ring position ratio, and the shift operation mechanism. As a result, the ring 5 is swung by a predetermined angle (steer angle) about the axis B, and the cone ring type CVT 1 is controlled so as to achieve the target engine speed.

  In the present invention, the correction value calculated from the change in the axial movement of the ring position and the ring rotational speed is involved in setting the required steer angle in the shift control unit 11 (20). That is, the movement change amount of the ring position x is detected by differentiation (x → dx / dt), and converted into the ring rotation speed (ring surface speed) based on the rotation speed No of the output side friction wheel (output cone). The steering angle (sin θ) of the ring is calculated.

FIG. 3 shows a theoretical formula for ring control. FIG. 3 shows a state where the ring 5 is in contact with the output-side conical friction wheel (output cone) 3 at a predetermined inclination angle (steer angle) θ and shift control is performed. The ring 5 is in contact with the output cone 3, the distance obtained by multiplying the velocity V of the outer diameter side surface of the ring 5 by the unit time Δt, and thereby the axial direction of the ring 5 by the unit time Δt by the steer angle θ. The relationship with the movement amount Δx is
(1 / V) × (Δx / Δt) = sin θ
It becomes. Since the steer angle θ is a minute angle, sin θ≈θ, and Δx is the difference (x−xreq) between the ring position x and the required ring position xreq, which is expressed by Equation 1. The surface velocity V of the ring is the same as the surface velocity V _Rin of the ring on the input side, assuming that the velocity error rate on the output side is zero. The ring surface speed V _Rin is developed as shown in Equation 4 by developing as shown in Equation 2 and Equation 3.

  The unit time Δt is expressed by the equation 4 by the proportional control gain kP and the integral control gain kI. Therefore, the ring steer angle θ is expressed by the equation 6 by the equations 1, 4 and 5. The ring position x may be obtained directly from the position of the ring 5 by a sensor, or may be obtained from the input rotational speed Ni and the output rotational speed No. The radius at the ring contact portion of each cone (friction wheel) It is calculated from the position.

  In the above-described embodiment, the rotation of the ring contact portion is calculated by the rotation speed of the output side friction wheel 3, but this may be calculated by the rotation speed of the input side friction wheel 2.

  Then, as shown in FIG. 2, the steer angle θ obtained by the theoretical formula 4 is averaged in a stable state. The averaged steering angle θ corrects a steering angle (detection angle) θ ′ based on an output signal value to the sensor (encoder) or the shift control actuator 6. The actuator 6 may be directly feedback controlled so that the corrected steer angle becomes the required steer angle. However, in the present embodiment, the correction value is stored as learning control.

  That is, the shift control unit 11 stores a plurality of shift maps based on torque and rotation speed, and the correction values calculated by the theoretical formula 4 are stored in these shift maps corresponding to the detected steering angles θ ′. The Further, the map stores a correction value for the spin torque acting on the ring 5 and a correction value for the slip ratio of the ring, using the input torque Ti, the traction oil temperature O, and the output cone rotation speed No as parameters. Then, the learned value of each correction map is directly derived from the input required ratio and the current ratio by the shift map, and is output to the shift control actuator 6 as an accurate required steer angle free from errors and variations.

  The learning control map is averaged in a stable state. The map includes a static correction map in a constant speed driving state a in which the ratio (speed ratio) is constant and the steer angle is 0, and a speed change driving state in which the ratio (speed ratio) is changed and the steer angle is inclined. a dynamic correction map at b.

  FIG. 4 is a diagram showing the specific learning control corrected by the above-described theoretical formula. First, a target engine speed, for example, 1000 rpm (Nin req = 1000 rpm) is calculated (S2). A required ratio, for example, 1.0 is calculated from the vehicle speed (S3). A required steer angle is calculated from the difference from the current ratio (S4). For example, when the ratio is 0.9 (Ratio = 0.9), the required steer angle is calculated as 0.3 (Ang req = + 0.3). In accordance with the running state, the required steer angle is corrected by learning control based on the above-described theoretical formula 4 (S5). For example, when the input torque (Tin) is 20 Nm and the input rotation speed (Nin) is 900 rpm, the correction term is −0.1 °, and the steer angle output value is 0.2 °. The shift control actuator 6 is operated based on the output value, and the ring 5 is tilted to a predetermined swing angle (steer angle) to shift the cone ring type CVT 1 (S6). The engine speed reaches the target value (1000 rpm) by the gear change of the cone ring type CVT1.

  The operation of the flowchart will be described with reference to the time chart of FIG. In the steer angle, the detected steer angle θ ′ based on the output value to the sensor (potentiometer) or the actuator 6 is shifted, and the actual steer angle θ ′ is 0 ° although the detected steer angle θ ′ indicates 0 °. Is in a positive position by the amount of deviation. Currently, the input rotational speed Nin is at 9000 rpm as shown by the broken line (overlapping with the solid line), the ratio (transmission ratio) is 0.9, and the transmission is 40 Kph. From this state, as shown in the flowchart described above, in order to set the engine speed (= input speed Nin) to the target value of 1000 rpm, the ratio is set to 1.0 and the actual steering angle is set to + 0.3 °. However, as described above, the detected steer angle θ ′ is deviated from the actual steer angle of the ring, and if the control is performed based on the deviated steer angle, the ratio is as shown by the one-dot chain line. , Exceeding 1.0, the target input rotational speed exceeds 1000 rpm. In the present invention, as shown by the solid line, a value close to the actual steer angle calculated from the theoretical formula is stored in the map, and the detected steer is detected by the correction value (−0.1) based on the theoretical value. The corner is corrected. That is, the shift control actuator 6 is based on the signal so that the correction term −0.1 ° is added to or subtracted from the detected steer angle +0.3, and the detected steer angle becomes +0.2 as indicated by a broken line. The inclination angle (steer angle) θ of the ring is controlled by feedback control.

  As a result, even if there is an error in the detected steer angle θ ′, the ring 5 is controlled to a value close to the actual target steer angle, and the shift control is performed so that the ratio becomes the target ratio 1.0 as shown by the solid line. Thus, the input rotational speed (engine rotational speed) becomes the target 1000 rpm.

  FIG. 5 is a diagram embodying the above-described shift control device. For the required ratio from the vehicle or the like, the ECU control unit 11a of the vehicle calculates the required steer angle from the difference from the current ratio based on the current axial position x of the ring from the ring position sensor 15. At this time, the required steering angle is set by learning control based on the theoretical formula 4 calculated from the ring rotation speed based on the output rotation speed from the output rotation sensor 16 and the movement change amount of the ring position, and the signal is transmitted to the CAN communication 17. Is transmitted to the driver control unit 11b. An actual steering angle signal based on the required steering angle is sent from the driver control unit 11b to the shift control actuator 6. The actuator 6 is connected to a cone ring CVT (transmission mechanism) via a ring (transmission operation) mechanism 12. 1 ring 5 is driven at a predetermined inclination angle (steer angle) with respect to the axis of the conical friction wheel about the line B. The steer angle of the ring 5 is detected by the encoder 13, the detected value is returned to the driver control unit 11b, and the actuator 6 is feedback-controlled so that the required steer angle is obtained.

  The position of the ring 5 that is inclined by the link (transmission operation) mechanism 12 and automatically moves in the axial direction by the rotation of the ring 5 is detected by the ring position sensor 15 as an actual ratio, and the axial direction from the sensor 15 Based on the position signal x, the ECU controller 11a calculates the current ratio of the CVT 1 and the radius of the output cone 3 with which the ring 5 contacts.

  Further, spin torque information based on experimental values is input to the shift control actuator 6. The spin torque acting on the ring varies depending on the axial force acting on the ring. The ring comes into contact with the input side friction wheel 2 and the output side friction wheel 3 under the action of a predetermined clamping pressure, and makes frictional contact in an extreme pressure state with traction oil interposed therebetween. The generated axial force is generated by the cam so as to correspond to the load torque acting on the cone ring type CVT1. As shown in FIG. 6, the input (or output) rotational speed Ni (or No) is input to the automatic correction control unit 20, and the output torque calculated by the engine torque, the ratio, and the like is calculated. The axial force is calculated based on the output torque with the output-side slip ratio being 0, and the axial force is input to the automatic correction control unit 20. Then, the spin torque acting on the ring is calculated by the axial force, and the correction value of the steering angle based on the spin torque is stored in the map. Also, the slip amount of the ring is calculated from the ring axial direction position and the actual friction ratio of the input side friction wheel and the output side friction wheel, and a correction value based on the slip amount is stored in the map together with the temperature of the traction oil. The steering angle derived from the rotation speed, input torque, and ratio from the map is output to the above-described shift control actuator 6 or its driver control unit 11b.

  FIG. 7 is a view similar to FIG. In the present embodiment, a driver control unit (see 11b in FIG. 5) of the shift control actuator 6 is incorporated in the shift control unit 11 '(corresponding to the ECU control unit 11a in FIG. 5). As a result, the required steer angle is calculated based on the ratio calculated from the position x in the ring axis direction, the detected steer angle θ ′ is fed back from the actuator 6, and a drive current is output from the shift control 11 ′ to the actuator 6. The Even in the present embodiment, the learning control based on the correction by the theoretical value is the same as that in the embodiment shown in FIG.

1 Conical friction wheel ring type continuously variable transmission (cone ring type CVT)
2 Input side friction wheel 3 Output side friction wheel 5 Ring 6 Actuator 12 Speed change (link) mechanism

Claims (7)

Conical input-side friction wheel and output-side friction wheel arranged so that the large-diameter side and the small-diameter side are opposite to each other on axes parallel to each other, and both friction wheels facing each other so as to surround one of these friction wheels A ring sandwiched between the inclined surfaces, a shift operation mechanism for operating the steering angle of the ring with respect to the axis to move the ring in the axial direction as the friction wheels rotate, and an actuator for operating the shift operation mechanism In a shift control device for a conical friction wheel ring-type continuously variable transmission, comprising:
In the steering angle control for controlling the actuator so that the detected steering angle of the ring becomes a required steering angle, the detected steering angle is calculated from the axial position change of the ring and the rotational speed of the ring. Compensated by the steer angle of the ring,
A transmission control device for a conical friction wheel ring type continuously variable transmission. The corrected value is learned and stored in a map, and the actuator is controlled based on the map.
The shift control device for a conical friction wheel ring type continuously variable transmission according to claim 1. The detected steering angle of the ring is an angle detected by a sensor disposed in the speed change operation mechanism.
The shift control device for a conical friction wheel ring type continuously variable transmission according to claim 1 or 2. The axial position of the ring is an axial position detected by a sensor disposed in the speed change operation mechanism.
4. A transmission control device for a conical friction wheel ring type continuously variable transmission according to claim 1. The axial position of the ring is calculated based on the rotational speeds of the input-side friction wheel and the output-side friction wheel,
4. A transmission control device for a conical friction wheel ring type continuously variable transmission according to claim 1. The rotational speed of the ring is calculated from the rotational speed of the input-side friction wheel or the output-side friction wheel and the axial position of the ring.
6. A transmission control device for a conical friction wheel ring type continuously variable transmission according to any one of claims 1 to 5. The learning map is a map that takes into account the spin torque acting on the ring,
A shift control device for a conical friction wheel ring type continuously variable transmission according to any one of claims 1 to 6.

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