JP6421386B2 - Reaction force output device - Google Patents

Description

  The present invention relates to a reaction force output device.

  An accelerator pedal device that outputs a force (reaction force) in the opposite direction to the force that depresses the accelerator pedal (stepping force) to the accelerator pedal, for example, in order to suppress unintended sudden acceleration when the vehicle starts or travels. It is known (see, for example, Patent Document 1).

  The accelerator pedal device described in Patent Document 1 includes a housing that pivotally supports the base end of a pedal arm, a return spring for returning the pedal arm to an initial position, a motor for creating a reaction force, A lever for transmitting the rotation of the motor to the pedal arm is incorporated. In this accelerator pedal device, the motor is controlled by the control device to an output corresponding to the depression state of the accelerator pedal, and the output is applied to the pedal arm through the transmission lever.

  Such a reaction force output device not only suppresses sudden acceleration, but also adopts a structure in which the connection between the accelerator pedal and the throttle valve is omitted (so-called drive-by-wire), the natural pedaling comfort of the accelerator pedal ( It is also used to give the driver an accelerator feeling).

JP 2010-111379 A

  However, in the reaction force output device described in Patent Literature 1, when the reaction force output instruction is not received from the host device, the operability of the operator may be felt poorly due to the friction torque of the drive motor. As a result, for example, when applied to an accelerator pedal device, the accelerator feeling may deteriorate.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a reaction force output device capable of suppressing the friction torque during a period when there is no reaction force output instruction.

The reaction force output device of the present invention employs the following configuration.
(1) The driving member outputs a force in the direction opposite to the operation direction of the operating element to the driving unit that drives the driving member and the operating element operated by a person when the input value is not zero. The drive unit controls the energization to the drive unit so that the drive member outputs a force in the same direction as the operation direction of the operation element when the input value is zero or the input value is not input. A control unit that controls energization of the drive unit, and when the input value is zero or the input value is not input, the control unit has passed a predetermined time after the signal indicating the displacement of the drive unit rises In addition, energization of the drive unit is started so that the drive member outputs a force in the same direction as the operation direction of the operation element .
According to this configuration, when the input value is zero or not input, the driving member controls the energization to the driving unit so that the driving member outputs a force in the same direction as the operation direction of the operation element. It is possible to suppress the friction torque during a period when there is no noise. Therefore, the reaction force output device can improve the feeling of stepping on the accelerator pedal, for example, when the driver steps on the accelerator pedal.
In addition, according to such a configuration, the reaction force output device can output a force in a direction opposite to the friction torque of the motor and suppress the friction torque, for example, after a predetermined time has elapsed since the motor started to rotate.

( 2 ) When the input value is zero or the input value is not input, the control unit passes a predetermined time after a signal indicating the displacement of the drive unit rises, and the drive amount of the drive unit is a threshold value When exceeding the above, energization of the drive unit may be started so that the drive member outputs a force in the same direction as the operation direction of the operation element.
According to such a configuration, the reaction force output device outputs a force in the direction opposite to the motor friction torque when the input value is zero or the input value is not input, for example, when the rotation speed of the motor exceeds a threshold value. In addition, the friction torque can be suppressed.
(3) In the control unit, when the input value is zero or when the input value is not input, the force output by the driving unit is smaller than the force output by the driving unit when the input value is not zero. In this way, energization to the drive unit may be controlled.
According to such a configuration, the reaction force output device outputs a force smaller than the force output by the drive unit when the input value is not zero when the input value is zero or the input value is not input. Thereby, the reaction force output device can suppress the friction torque within a range where the motor does not rotate, for example.

  ADVANTAGE OF THE INVENTION According to this invention, the reaction force output device which can suppress the friction torque in the period when there is no reaction force output instruction can be provided.

It is a figure showing an example of the appearance composition of accelerator pedal device 1 provided with reaction force output device 10 concerning one embodiment. It is a figure showing an example of an internal structure of reaction force output device 10 concerning one embodiment. It is a figure showing an example of functional composition centering on a control circuit of reaction force output device 10 concerning one embodiment. FIG. 6 is a conceptual diagram showing an example of the direction and magnitude of force applied to the pedal body 6. It is a figure which shows an example of the timing which performs normal control and friction torque suppression control. It is a flowchart which shows the flow of the process performed by the control circuit of the reaction force output device 10 which concerns on one Embodiment.

  Hereinafter, embodiments of a reaction force output device of the present invention will be described with reference to the drawings. A reaction force output device according to an embodiment outputs, for example, a force (reaction force) opposite to a stepping force (stepping force) to an operator such as an accelerator pedal provided for instructing acceleration of the vehicle. Device. By using the reaction force output device, it is possible to improve the accelerator feeling, to transmit the accelerator work that saves fuel consumption, and to perform various safety controls. Safety control includes control that outputs a relatively large reaction force in order to suppress excessive acceleration before a curve, in an urban area, a school zone, or the like. In addition, when the accelerator pedal is simply operated exceeding the reference, it may be determined that the operation is erroneous and control to output a large reaction force may be performed. In addition, the operation element that is the reaction force output target in the present embodiment is not limited to the accelerator pedal, and may be a brake pedal, a steering wheel, an operation device of a game machine, or the like.

Drawing 1 is a figure showing an example of the appearance composition of accelerator pedal device 1 provided with reaction force output device 10 concerning one embodiment.
The accelerator pedal device 1 includes a pedal body unit 2 installed in front of the driver's seat and a reaction force output device 10 installed above the pedal body unit 2.

  The pedal body unit 2 is provided on a holding base 2a attached to the vehicle body, a pedal arm 4 whose base end is rotatably supported by a support shaft 2b provided on the holding base 2a, and a distal end portion of the pedal arm 4. The holding base 2a is provided with a return spring (not shown) that constantly urges the pedal arm 4 to the initial position.

  A cable (not shown) for operating the opening of a throttle valve (not shown) of the internal combustion engine (engine) is connected to the pedal arm 4 in accordance with the operation amount (rotation angle) of the pedal arm 4. However, when the internal combustion engine employs an electronically controlled throttle, a rotation sensor for detecting the rotation angle of the pedal arm 4 is provided in the pedal body unit 2, and the throttle valve is detected based on the detection signal of the rotation sensor. The opening degree may be controlled. Further, a reaction force transmission lever 8 extending in a direction substantially opposite to the extending direction of the pedal arm 4 is integrally connected to the vicinity of the base end of the pedal arm 4.

  Further, the distal end portion of the output lever 12 that is a driving member of the reaction force output device 10 and the distal end portion of the reaction force transmission lever 8 can be brought into contact with each other. The turning force of the output lever 12 that is a drive member of the reaction force output device 10 is output to the pedal arm 4 via the reaction force transmission lever 8. In this way, the reaction force output device 10 outputs a reaction force in the direction opposite to the direction of the pedaling force to the operator.

  FIG. 2 is a diagram illustrating an example of the internal structure of the reaction force output device 10 according to an embodiment. In FIG. 2, the cover of the upper surface of the housing member 14 is removed, and the internal state of the housing member 14 (reaction force output device 10) is shown. The reaction force output device 10 according to the present embodiment includes a motor 20 that is a drive source for creating a reaction force, a reaction force output shaft 16 that is pivotally supported by the housing member 14, a gear reduction mechanism 30, and the like. And a circuit board 50. The gear reduction mechanism 30 decelerates the rotation of the rotor of the motor 20 and increases the torque T output from the motor 20 side, and increases the torque T by deflecting from the motor rotation shaft 22 direction to the reaction force output shaft 16 direction. T is transmitted to the output lever 12. One end portion in the reaction force output shaft direction protrudes outward from the side surface of the housing member 14, and the output lever 12 is integrally connected to the protruding end portion.

  The gear reduction mechanism 30 includes, for example, a one-way clutch 32 that allows the output lever 12 to move in the direction in which the pedal arm 4 returns. For this reason, when the driver removes his / her foot from the pedal arm 4, the pedal arm 4 returns to the original position by the action of the return spring and the one-way clutch 32 described above. On the other hand, the one-way clutch 32 does not allow the output lever 12 to move to the direction output lever 12 in which the pedal arm 4 is depressed. Therefore, when the pedal arm 4 is depressed, the motor 20 is rotated. As a result, the driver may receive an unintended reaction force when starting to depress the pedal arm 4, and may feel the pedal heavy. This reaction force is a force resulting from the friction torque of the motor 20 when no power is supplied. In particular, the friction torque is more likely to be generated more significantly as the gear ratio in the gear reduction mechanism 30 is larger.

  The rotation of the rotor of the motor 20 is controlled by a control circuit mounted on the circuit board 50. Connected to the circuit board 50 is a CAN (Controller Area Network) cable (not shown) for transmitting and receiving signals between a host ECU (Electronic Control Unit) described later and a control circuit. The circuit board 50 and the motor 20 are connected via a cable (not shown), and the rotation of the rotor of the motor 20 is controlled based on a control signal sent from the circuit board 50. In addition, a small hole, a slit, or the like is provided in the housing that covers the rotor of the motor 20, and a Hall IC (Integrated Circuit) is fitted into the small hole, the slit, or the like. The Hall IC detects the magnetic flux intensity that passes through a small hole, a slit, or the like, and outputs a pulsed voltage corresponding to the detected magnetic flux intensity. The magnetic flux intensity detected by the Hall IC changes according to the rotation of the rotor in the motor 20. For this reason, the reaction force output device 10 can detect the rotation amount of the rotor based on the output voltage of the Hall IC. The reaction force output device 10 calculates the rotation speed n based on, for example, the timing interval at which the magnetic flux intensity detected by the Hall IC exceeds a threshold value. As described above, due to the action of the one-way clutch 32, the output of the Hall IC indicates the rotation of the rotor of the motor as the pedal arm is depressed.

  FIG. 3 is a diagram illustrating an example of a functional configuration centering on a control circuit of the reaction force output device 10 according to the embodiment. In FIG. 3, the reaction force output device 10 includes a CAN control circuit 54 that performs CAN communication between the motor 20 and the host ECU 70, a microcontroller (microcomputer) 56, a motor driver IC 58, a power FET (Field Effect Transistor). ) 60, Hall IC 64U, 64V, 64W, Hall IC 64, and current detection sensor 66. In the following description, the Hall ICs 64U, 64V, and 64W are collectively referred to as the Hall IC 64 unless otherwise distinguished.

  For example, the host ECU 70 controls the driving of the engine 72 by controlling the opening degree of the throttle valve in accordance with the operation amount of the pedal arm 4. In the engine 72, a crankshaft as an output shaft is connected to an axle, and outputs a driving force for driving the vehicle. The travel drive unit may have a configuration in which a travel motor is added to the engine 72, or may have a configuration in which the travel drive force is output only by the travel motor without the engine 72.

  The microcomputer 56 performs CAN communication with the host ECU 70 via the CAN control circuit 54. The microcomputer 56 is an example of a “control unit”. The microcomputer 56 receives a reaction force set value P, which is a reference for the magnitude of the reaction force generated by the reaction force output device 10, from the host ECU 70. The reaction force set value P is an example of “input value”. The reaction force set value P is set to zero, for example, when the accelerator opening is small (for example, 0 [%] to 10 [%], etc.) or when the reaction force is set to the reaction force off mode by the driver. Sometimes. In this case, the reaction force set value P itself may not be transmitted.

  The microcomputer 56 determines the current command value I as a control amount to be given to the motor driver IC 58 based on the reaction force set value P. At this time, the microcomputer 56 determines the current command value I based on information such as the current command value I, the reaction force set value P, and the rotation speed of the motor 20, for example. The motor driver IC 58 determines a pulse width, a duty ratio, and the like at the time of PWM control based on the current command value I, controls a current to be supplied to the power FET 60, and rotates the motor 20. The microcomputer 56 uses the current command value I as a control target value, and performs, for example, PI control (Proportional-Integral Controller) on the control target value.

  The power FET 60 includes U-phase, V-phase, and W-phase power FETs 60U, 60V, and 60W, and each power FET is connected to a coil of a corresponding phase of the motor 20, respectively. The motor driver IC 58 cyclically turns on / off each phase power FET to generate a magnetic field in each phase coil, and rotates the rotor of the motor 20.

  The microcomputer 56 is connected to a current detection sensor 66 for detecting a current supplied to the motor 20 and a motor driver IC 58. The microcomputer 56 receives a signal indicating the current detected by the current detection sensor 66. In addition to the microcomputer 56, three Hall ICs 64U, 64V, 64W are connected to the input terminal of the motor driver IC 58, and the motor driver IC 58 accepts a change in voltage output from each of the Hall ICs 64U, 64V, 64W. The motor driver IC 58 outputs a signal indicating the rotational speed n of the motor 20 to the microcomputer 56 based on the input from the Hall ICs 64U, 64V, 64W.

  Here, in principle, when the reaction force set value P received from the host ECU 70 is zero (or when the signal indicating the set value itself is not received), the reaction force output device uses a current based on the reaction force set value P. Do not energize the motor.

  However, the driver is affected by the friction torque of the motor 20 when the pedal body portion 6 is depressed during a period when the reaction force set value P is zero or the reaction force set value P is not received, and the pedal body portion 6 May feel heavy.

  Therefore, the reaction force output device 10 of the present embodiment has a pedal body portion so as to suppress the friction torque of the motor 20 during a period in which the current based on the current command value I (reaction force setting value P) is not applied to the motor 20. The motor 20 is energized with a minute current for outputting a force in the same direction as the operation direction 6. Hereinafter, with reference to the drawings, a process for applying a minute current to the motor 20 will be described.

  FIG. 4 is a conceptual diagram showing an example of the direction and magnitude of the force applied to the pedal body 6. The right side force from the base line LN1 shown in the drawing includes a part of the force received by the motor 20, and the left side force from the base line LN1 includes a part of the force received by the driver when the pedal body portion 6 is depressed. .

  In order to suppress the friction torque of the motor 20, the microcomputer 56 generates a second magnetic field opposite to the first magnetic field formed inside the motor 20 when a current based on the current command value I is supplied to the motor 20. A current command value to be formed is determined. That is, the reaction force output device 10 can generate a reverse force that cancels or reduces the friction torque by forming the second magnetic field inside the motor 20. Hereinafter, the current command value that causes the motor 20 to form the second magnetic field is referred to as “current command value I #”. Further, the control for energizing the motor 20 with a current based on the current command value I is referred to as “normal control”, and the control for energizing the motor 20 with a current based on the current command value I # is performed with “friction torque suppression”. This is referred to as “control”.

  For example, the current command value I # is appropriately changed according to the assumed magnitude of the friction torque, and is set so that the magnitude of the force generated by the second magnetic field is equal to or less than the friction torque. The Current command value I # may be a predetermined value that is determined in advance. The microcomputer 56 supplies the determined current command value I # to the motor driver IC 58, thereby energizing the motor 20 with a minute current that does not rotate the rotor of the motor 20.

  FIG. 5 is a diagram illustrating an example of timing for performing normal control and friction torque suppression control. In the graphs G1 to G3 in the figure, the vertical axis represents the pulse voltage [V] of the Hall IC 64, the accelerator opening, and the current [A] energized to the motor 20, and the horizontal axis represents the time t [s. ]. As described above, the pulse voltage [V] of the Hall IC 64 indicates the rotation of the rotor of the motor as the pedal arm is depressed.

  For example, when the driver starts stepping on the pedal arm 4 at time t1 and finishes stepping at time t3, the Hall IC 64 outputs a pulse voltage that rises at time t1 and falls at time t3. In this period, the accelerator opening gradually increases from time t1 to t3 and starts to decrease from time t3.

  Therefore, the microcomputer 56 is a time t2 when a predetermined time Δt (for example, 50 [ms]) has elapsed from the time t1 when the pulse voltage output from the Hall IC 64 rises in a period in which the current based on the reaction force setting value P is not applied to the motor 20. Then, the friction torque suppression control is started. Further, the microcomputer 56 ends the friction torque suppression control at time t3 when the pulse voltage output from the Hall IC 64 falls, that is, at time t3 when the rotational speed n of the motor 20 becomes equal to or less than the threshold Th. The friction torque suppression control may be started immediately at time t1 when the pulse voltage output from the Hall IC 64 rises, or is continuously performed for a period until the next reaction force setting value P is received. May be.

  FIG. 6 is a flowchart showing a flow of processing executed by the control circuit of the reaction force output device 10 according to the embodiment. The processing of this flowchart is repeatedly executed at a predetermined cycle, for example.

  First, the reaction force output device 10 determines whether or not the reaction force setting value P received from the host ECU 70 is zero (or does not receive the reaction force setting value P) (step S100). If the reaction force set value P is not zero, the microcomputer 56 determines the current command value I based on the reaction force set value P (step S102), gives the determined current command value I to the motor driver IC 58, and performs normal control. This is performed (step S104). Thereby, the reaction force output apparatus 10 ends one routine of this flowchart.

  If the reaction force set value P is zero (or does not receive the reaction force set value P) (step S100: Yes), the microcomputer 56 has passed a predetermined time (or has been operated by a predetermined amount) after the motor 20 starts rotating. It is determined whether or not (step S106). The reaction force output device 10 ends one routine of this flowchart when the predetermined time has not elapsed (or the predetermined amount has not been operated) after the motor 20 starts rotating (step S106: No).

  When a predetermined time has elapsed (or a predetermined amount has been operated) since the motor 20 started rotating, the microcomputer 56 determines whether or not the rotational speed n of the motor 20 has exceeded the threshold Th (step S108). When the rotation speed n of the motor 20 does not exceed the threshold Th, the reaction force output device 10 ends one routine of this flowchart. Note that the determination process in step S108 may be omitted.

  When the rotational speed n of the motor 20 exceeds the threshold Th, the microcomputer 56 determines the current command value I # (step S110), gives the determined current command value I # to the motor driver IC 58, and performs friction torque suppression control. This is performed (step S112). Thereby, the reaction force output apparatus 10 ends one routine of this flowchart.

  As described above, according to the reaction force output device 10 according to the present embodiment, when the reaction force setting value P received from the host ECU is not zero, the reaction force is output to the pedal body 6. Then, when the reaction force setting value P is zero or the reaction force setting value P is not received, control is performed so as to output a force in the same direction as the operation direction. Thereby, the reaction force output device 10 can suppress the friction torque during a period when there is no reaction force output instruction. As a result, the reaction force output device 10 can provide a pedal operation with a comfortable feeling for the driver.

  Further, the reaction force output device 10 according to the present embodiment can set the gear ratio in the gear reduction mechanism 30 to be larger by suppressing the friction torque of the motor 20 during a period when there is no reaction force output instruction. . As a result, the motor 20 can be driven with power saving, and the heat generation of the motor 20 can be suppressed.

  As mentioned above, although the form for implementing this invention was demonstrated using embodiment, this invention is not limited to such embodiment at all, In the range which does not deviate from the summary of this invention, various deformation | transformation and substitution Can be added.

DESCRIPTION OF SYMBOLS 1 ... Accelerator pedal apparatus, 2 ... Pedal main body unit, 6 ... Pedal main body part, 10 ... Reaction force output device, 20 ... Motor, 30 ... Gear reduction mechanism, 32 ... One-way clutch, 50 ... Circuit board, 56 ... Microcomputer, 58 ... Motor driver IC, 70 ... Host ECU, 72 ... Engine

Claims (3)

A drive unit for driving the drive member;
When the input value is not zero, for the operator operated by a person, the energization to the drive unit is controlled so that the drive member outputs a force in the direction opposite to the operation direction of the operator,
When the input value is zero or the input value is not input, and a control unit for controlling power supply to the drive unit so that the driving member and outputs a force in the same direction as the operation direction of the operating element ,
In the case where the input value is zero or the input value is not input, the control unit is configured such that when a predetermined time elapses after a signal indicating the displacement of the drive unit rises, the drive member changes the operation direction of the operator. Start energizing the drive to output force in the same direction,
Reaction force output device. When the input value is zero or the input value is not input, the control unit has passed a predetermined time after the signal indicating the displacement of the drive unit rises, and the drive amount of the drive unit has exceeded a threshold value Sometimes, the drive member starts energization to the drive unit so as to output a force in the same direction as the operation direction of the operator.
The reaction force output device according to claim 1 . The control unit is configured so that the force output by the drive unit when the input value is zero or the input value is not input is smaller than the force output by the drive unit when the input value is not zero. Control the energization of the drive,
The reaction force output device according to claim 1 or 2 .

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