JP2014043236A - Accelerator pedal device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an accelerator pedal device that serves to improve power consumption and enhance drivability.SOLUTION: An accelerator pedal device comprises: a mechanism portion for converting a pedal force to a stepping torque through a pedal arm 110; an electronically controlled damper 140 for generating a braking force in a direction opposite to a stepping direction of the pedal arm 110; and a control device 150 for supplying the electronically controlled damper 140 with electric power and controlling the amount of the braking force, where the electronically controlled damper 140 generates the braking force only when the stepping angle of the pedal arm 110 increase. Therefore, the electronically controlled damper 140 does not generate the braking force when the amount of pedal stepping remains unchanged, therefore saving power consumption. During travelling at constant speed, the accelerator pedal divice does not give a braking force to a driver's foot, serving to reduce fatigue of the driver.

Description

  The present invention relates to an accelerator pedal device, and more particularly to a device including an electronically controlled damper.

  In recent years, electronic control of in-vehicle components of automobiles (internal combustion engine type automobiles, EV, HEV, P-HEV) has been promoted under the demand for reduction of fuel consumption. This request for electronic control is also a matter imposed on an accelerator pedal device that adjusts the speed of an automobile.

  As an example, Japanese Patent Laid-Open No. 2006-193012 (Patent Document 1) introduces an accelerator pedal device including a motor that generates a reaction force. The technique introduced in Patent Document 1 will be described with reference to the upper part (prior art) of FIG. This figure is a schematic diagram showing the behavior of the accelerator pedal device provided on the driver's seat floor.

  According to Patent Document 1, this apparatus includes a motor as an actuator. As shown in FIG. 6, a scene during acceleration traveling (a pedaling force (a force to step on the pedal plate 170) fg is applied to the pedal plate 170). In a case where the depression angle θ of the pedal arm 110 is increased), the motor is operated to generate a reaction force fm in a direction (return direction) opposite to the depression direction (the direction in which the pedal arm 100 rotates at this time). This device is configured to control the reaction force fm in accordance with the depression angle θ from the initial position A. If the pedal plate 170 is depressed from the initial position A, the reaction force fm is generated. Yes.

JP 2006-193012 A

  However, in the technique according to Patent Document 1, as shown in FIG. 6, even when the vehicle is traveling at a constant speed (a scene where the stepping angle θ is constant and does not change), if the stepping angle θ is generated, the motor Since torque is output, a reaction force fm is applied to the driver's feet. Therefore, since this apparatus always generates the reaction force fm while the pedal plate 170 is depressed, the power consumption of the motor increases.

  Further, when the driver wants to keep the stepping angle θ constant, the reaction force fm is always applied to the foot while the driver steps on the pedal plate 170, so that the driver can react with the reaction force fm (more precisely, the reaction force fm). Includes the torque generated by the elastic force of the return spring.) The pedaling force fg must be continuously adjusted to balance the torque. For example, in long-distance driving on an expressway, since there is little change in the traffic environment, the vehicle may be driven at a constant speed without changing the amount of depression of the pedal plate 170. However, in the technique of Patent Document 1, since the output of torque from the motor continues even in such a constant speed driving situation, it is necessary to adjust the pedaling force fg by the driver, and the degree of driver fatigue is increased. End up.

  In addition, the use of a motor has a problem that the size of the apparatus is increased. Furthermore, since various members that transmit the torque of the motor are interposed between the pedal arm 110 and the motor, there is a problem that the responsiveness to the behavior of the pedal arm 110 is lowered and the operational feeling is deteriorated.

  The problem to be solved by the present invention is to provide an accelerator pedal device that contributes to improved power consumption and improved drivability. It is another object of the present invention to provide an accelerator pedal device that contributes to downsizing of the device and improvement of response.

In order to solve the above problems, the present invention provides the following accelerator pedal device.
1. A mechanism that converts a pedaling force into a stepping torque via a pedal arm, an electronically controlled damper that generates a braking force in a direction opposite to the stepping direction of the pedal arm, and a magnitude of the braking force that applies electric power to the electronically controlled damper And an electronically controlled damper that generates the braking force only when a depression angle of the pedal arm is increased.
2. 2. The accelerator pedal device according to 1 above, wherein the electronically controlled damper is a variable braking mechanism using a rotating electric machine including a rotor and a stator.
3. 2. The accelerator pedal device according to 1, wherein the electronically controlled damper is a variable braking mechanism using a magnetorheological fluid or an electrorheological fluid.
4). 2. The accelerator pedal device according to claim 1, wherein the control device determines a set value of the braking force based on the depression angle.
5. The control device is configured to set the stepping angle from the first critical angle at which the stepping angle starts to increase to the second critical angle that is set below the inflection point of the setting value. 5. The accelerator pedal device as described in 4 above, wherein the rate of increase of the value is continuously increased.
6). A pedal arm that is rotatably installed; a return spring that returns the pedal arm to an initial position; and an electronically controlled damper that generates a braking force that acts on the pedal arm, the electronically controlled damper comprising: An accelerator pedal device comprising a rotary variable braking mechanism using a magnetorheological fluid as a working medium.
7). The electronically controlled damper generates a braking force in the direction opposite to the rotation direction of the pedal arm (that is, when the pedal arm rotates in the depression direction, the braking force is generated in the return direction, and the pedal arm 7. The accelerator pedal device according to claim 6, wherein the accelerator pedal device is configured to generate a braking force in the depression direction when the motor rotates in the return direction.
8). The electronically controlled damper includes a chamber filled with the magnetorheological fluid, and a cylindrical rotor rotatable in the chamber, and shear stress of the magnetorheological fluid causes an outer peripheral surface and an inner periphery of the cylindrical rotor. 7. The accelerator pedal device according to 6, wherein the accelerator pedal device is configured to act on a surface.
9. The accelerator pedal device according to claim 6, wherein the electronically controlled damper includes a displacement sensor capable of detecting a rotation angle of the pedal arm (that is, an increase and a decrease in a depression angle of the pedal arm).

  According to the first to fifth aspects of the present invention, the braking force acts in the direction opposite to the depression direction only when the depression angle of the pedal arm is increased. Therefore, when there is no change in the amount of depression, no braking force is generated, so that the power consumption of the electronically controlled damper can be suppressed. In addition, in a scene during constant speed traveling, no braking force is applied to the driver's feet, which contributes to suppressing the driver's fatigue.

  According to the present invention described in 6 to 9, since the electronically controlled damper is a rotary variable braking mechanism using a magnetorheological fluid as a working medium, it is possible to generate a high torque even with a small size, and a pedal. The configuration for transmitting torque to the arm can be extremely simplified. Therefore, it is possible to reduce the size of the apparatus. Further, since it becomes possible to generate a braking force that quickly corresponds to the behavior of the pedal arm, it contributes to an improvement in operational feeling.

FIG. 1 is an exploded perspective view of the accelerator pedal device according to the first embodiment. FIG. 2 is a perspective view of the accelerator pedal device according to the first embodiment. FIG. 3 is a perspective view illustrating a state in which the pedal plate is attached to the accelerator pedal device according to the first embodiment. FIG. 4 is a block diagram illustrating the configuration of the control device employed in the first embodiment. FIG. 5 is a graph showing the relationship between the set value of the braking force and the depression angle. FIG. 6 is a diagram comparing the behavior of the prior art and the behavior of the first embodiment. FIG. 7 is an exploded perspective view of the accelerator pedal device according to the second embodiment. FIG. 8 is a perspective view of the accelerator pedal device according to the second embodiment. FIG. 9 is a perspective view of the electronically controlled damper employed in the second embodiment. FIG. 10 is a cross-sectional view showing the internal structure of the electronically controlled damper employed in the second embodiment. FIG. 11 is a layout diagram of the rotation shaft and the displacement sensor. FIG. 12 is a graph showing the relationship between the load torque and the depression angle.

  Embodiments of the present invention will be specifically described below with reference to the drawings.

  FIG. 1 is an exploded perspective view of the accelerator pedal device according to the first embodiment, and FIG. 2 is a perspective view of the same embodiment. As shown in these drawings, the accelerator pedal device 100 includes a pedal arm 110, a first member 120 and a second member 130 constituting a housing, an electronically controlled damper 140, a control device 150, and a return spring 160. And is configured.

  The pedal arm 110 includes a bearing storage portion 113, a pedal plate mounting portion 111 that exists in front of the bearing storage portion 113, and a return spring connection portion 112 that exists in the rear of the bearing storage portion 113. A bearing such as a bearing or a sliding bearing is fixed inside the bearing housing 113. The said bearing plays the role which relieve | moderates the friction of the radial direction produced between the shaft bodies inserted in the inside.

  As shown in FIG. 3, the pedal plate 170 is mounted on the pedal plate mounting portion 111 after the accelerator pedal device 100 is assembled.

  Returning to FIG. 1, one end of the return spring 160 is fixed to the return spring connecting portion 112. In this embodiment, a compression coil spring is adopted as the return spring 160. The return spring 160 is compressed by the return spring connecting portion 112 when the pedal arm 110 rotates in the depression direction. Accordingly, the elastic force of the return spring 160 is applied to the return spring connecting portion 112.

  The first member 120 includes a return spring housing part 121, a pedal arm housing part 124, and a fenestration part 122. A return spring 160 is stored in the return spring accommodating portion 121. The other end of the return spring 160 is in contact with the inner surface of the return spring accommodating portion 121.

  A sliding shaft 123 is provided in the pedal arm accommodating portion 124. The sliding shaft 123 has a cylindrical shaft body. The shaft body is fitted into a bearing fixed inside the bearing housing 113, whereby the pedal arm 110 is attached to the first member 120 so as to be able to rotate within a certain range.

  Since the pedal arm 110 is connected to the return spring 160, when the pedal arm 110 rotates in the stepping direction, the elastic force of the return spring 160 increases accordingly. The pedal arm 110 is returned to the initial position A by this elastic force.

  The second member 130 includes a pedal arm housing part 134 and a fenestration part 131. The pedal arm housing part 134 is provided with an opening 132 and a plurality of through holes 133. The opening 132 is formed at a position corresponding to the bearing storage portion 113. The plurality of through holes 133 are formed around the opening 132.

  The fenestration part 131 is symmetrical with the fenestration part 122. The fenestration part 131 and the fenestration part 122 form one rectangular window when the first member 120 and the second member 130 are combined. As shown in FIG. 2, the pedal plate mounting portion 111 is disposed so as to protrude from the rectangular window to the outside. The opening size of the rectangular window is determined according to the operating range of the pedal arm 110.

  In the present embodiment, the first member 120 and the second member 130 are combined to form a housing. In this embodiment, the pedal arm 110, the housing, and the return spring 160 constitute one mechanism. When a pedaling force is applied to the pedal plate 170, the mechanism unit converts the force into a pedaling torque via the pedal arm 110.

  The electronically controlled damper 140 is a damper that generates a braking force when electric power is input. In the present embodiment, a variable braking mechanism using a rotating electric machine configured by including a rotor and a stator is employed as the electronically controlled damper 140. The variable braking mechanism generates a braking force on the fixed shaft of the rotor by controlling the electrical angle. In this operation, a desired braking force is generated by using a method of retarding the electrical angle from the d-axis current coinciding with the magnetic flux direction of the rotor, a method of fixing the electrical angle, or the like.

  As shown in FIG. 2, the electronically controlled damper 140 is fixed to the second member 130. The fixed shaft of the rotor is fixed to the bearing storage portion 113 exposed from the opening 132. Thereby, the operation of the pedal arm 110 and the rotor are interlocked. Here, the braking force of the electronically controlled damper 140 acts in a direction opposite to the stepping direction. Accordingly, a resistance force in a direction opposite to the stepping direction is applied to the feet of the driver who steps on the pedal plate 170. Then, by adjusting the electric power applied to the electronically controlled damper 140, the resistance force applied to the foot when the pedal plate 170 is depressed is controlled.

  As shown in FIG. 1, the electronically controlled damper 140 is provided with a rotation variable resistor 140a in order to detect the depression angle θ. The rotation variable resistor 140a outputs a position signal Sθ indicating the rotation angle (depression angle θ) of the pedal arm 110. However, the present invention is not limited to this, and angle detection may be performed using another sensor.

  The electronically controlled damper 140 generates a braking force only when the depression angle θ of the pedal arm 110 increases. That is, the braking force acts on the pedal arm 110 only when the pedal plate 170 is depressed. Therefore, only the resistance by the elastic force of the return spring 160 is given to the driver's feet while the depression angle θ is kept constant. The operation of the electronically controlled damper 140 is controlled by the control device 150.

  The control device 150 includes a housing 151, a circuit board 152, and a lid 153. The casing 151 includes a lid 151 a and a connector 151 b that close the opening of the return spring accommodating portion 121. The circuit board 152 is stored inside the housing 151. The lid 153 closes the opening of the housing 151.

  The control device 150 is attached to an appropriate position of the second member 130. A power cable connected to the electronically controlled damper 140 is connected to the connector 151b. The connector 151b is also connected to a CAN communication line.

  Appropriate circuits are mounted on the circuit board 152. Each of the circuits includes an inverter circuit on which a plurality of power transistors are mounted, an I / O circuit that inputs and outputs signals, an A / D conversion circuit, and A signal processing circuit including a CPU and a memory is configured.

  The inverter circuit appropriately converts electric power supplied from the outside and controls the phase current supplied to the electronically controlled damper 140. The control device 150 controls the electrical angle by the function of the inverter circuit, thereby controlling the magnitude of the braking force exerted by the electronically controlled damper 140.

  The signal processing circuit stores various programs in a storage device such as a memory, and this software resource and hardware resource cooperate to construct various functions to be described later. In such a program, a command for realizing the function is described, and the desired function is realized by sequentially executing the command. In this operation, program command information is read into the instruction register via the bus line, and processing to be executed is performed based on the command information.

  FIG. 4 is a block diagram illustrating a configuration of the control device 150. The function of the control device 150 relates to the control of the current applied to the electronically controlled damper 140. The control device 150 includes a braking force setting unit 150a, a subtraction unit 150b, a feedback control unit 150c, a PWM signal generation unit 150d, and a braking force calculation unit 150e.

  In FIG. 4, reference numeral 140b denotes a current detection unit, which detects a phase current using a Hall element, a current transformer, or the like. The current value signal detected by the current detection unit 140b is output to the signal processing circuit (braking force calculation unit 150e) via the signal line.

  The braking force setting unit 150a determines a braking force set value freq based on the depression angle θ. In the braking force setting unit 150a, as shown in FIG. 5, the relationship between the braking force set value freq and the depression angle θ is defined by a characteristic curve.

  The braking force setting unit 150a receives the position signal Sθ from the rotation variable resistor 140a, and thereby acquires information on the depression angle θ. In addition, the braking force setting unit 150a selects the strength of the braking force based on the operation mode information iDM.

  In this embodiment, as shown in FIG. 5, the driving mode can be selected from the sports mode S-mode, the normal mode C-mode, and the environmental protection mode E-mode, and the braking force is strong in this order. A characteristic curve is defined so that

  Hereinafter, the characteristics of the characteristic curve of the braking force set value freq will be described with reference to the environmental protection mode E-mode shown in FIG.

  First, when the driver steps on the pedal plate 170 and the pedal arm 110 rotates in the depression direction from the initial position A, the depression angle θ increases from the initial position A (θ = 0). When the stepping angle θ reaches the first critical angle θ1, the control device 150 starts increasing the set value freq. As the depression angle θ increases, the set value freq increases from the lower limit value fa of the braking force, and the curve increase rate (the increase rate of the set value freq with respect to the depression angle θ) gradually increases. Go. Thus, by increasing the increase rate of the set value freq according to the depression angle θ, it is possible to make the driver feel the increase in load sensitively. As a result, overthrottle can be effectively eliminated.

  In the present embodiment, the upper limit value fb of the braking force is set, and saturation is performed at the threshold value so that the braking force does not become excessively strong. The significance of setting the upper limit value fb of the braking force is in consideration of an emergency scene that requires rapid acceleration.

On the other hand, in normal driving, it is desirable to avoid driving close to full throttle as much as possible in consideration of fuel efficiency and safety. Therefore, in a scene where normal driving is performed, the depression angle θ is expressed by
θ1 ≦ θ ≦ θ2
It is designed to be within the range of.

  Under such circumstances, the second critical angle θ2 is set to an angle at which the saturation of the set value freq is not started, and in order to satisfy this, the second critical angle θ2 is set to the set value freq. It should be set below the inflection point. By setting in this way, the increase rate of the set value freq is continuously increased until the second critical angle θ2 is reached, and the driver perceives an increase in braking force in that range.

  In the present embodiment, the second critical angle θ2 is set at the inflection point of E-mode. This is because E-mode has the highest rate of increase compared to C-mode and S-mode, and by doing so, the above-mentioned conditions are satisfied for all operation modes. is there.

  When the braking force setting unit 150a determines the braking force setting value freq, the setting value freq is given to the subtraction unit 150b. In the subtracting unit 150b, the actual braking force fins is given, and a difference value Δf between the set value freq and the braking force fins is calculated.

  In the feedback control unit 150c, a proportional gain and an integral gain are set, and the d-axis current and the q-axis current are calculated based on the input difference value Δf. These currents specify the electrical angle in the electronically controlled damper 140. Then, the feedback control unit 150c calculates and outputs a three-phase current command value based on the calculated d-axis current and q-axis current.

  The PWM signal generation unit 150d compares the command value of the three-phase current with the carrier wave to generate the PWM signal Spwm. The PWM signal Spwm output from the PWM signal generation unit 150d is provided to the inverter circuit. In this embodiment, electric power is supplied to the electronically controlled damper 140 through this inverter circuit.

  The electronically controlled damper 140 generates a braking force when electric power is supplied. At this time, power is consumed. On the other hand, in a scene where the braking force is unnecessary (that is, a scene where the depression angle θ of the pedal arm 110 detected by the rotation variable resistor 140a is not increased), all the power transistors of the inverter circuit are turned off. Thus, power consumption of the electronically controlled damper 140 is suppressed.

  The current detection unit 140b detects the phase current and outputs a detection signal Iins indicating the phase current to the braking force calculation unit 150e. The braking force calculation unit 150e receives the detection signal Iins and converts information related to the phase current into electrical angle components (d-axis current and q-axis current).

  Further, the braking force calculation unit 150e calculates the braking force fins actually generated from the electronically controlled damper 140 based on the electrical angle component. Since the braking force fins has a linear relationship with the electrical angle component, it can be calculated based on this relationship.

  The calculated braking force fins is fed back to the subtraction unit 150b. The feedback control unit 150c calculates a command value for the electrical angle component so as to decrease the difference value Δf according to the proportional gain. Further, in the feedback control unit 150c, the integral gain is appropriately set, thereby avoiding excessive setting of the braking force set value freq. In the feedback control unit 150c, PI control is functioned. However, PID control may be adopted when it is desired to improve the response speed.

  As described above, the accelerator pedal device 100 according to the present embodiment is configured to generate the braking force only when the depression angle θ of the pedal arm 110 is increased. Therefore, if the depression angle θ does not increase, load torque is not applied to the driver's feet. For this reason, as shown in FIG. 6, in the scene during acceleration traveling, the driver applies a pedaling force fg larger than the braking force fins acting on the pedal arm 110 in the return direction to the pedal plate 170 to depress the depression angle. θ must be increased. Therefore, sudden start and rapid acceleration can be suppressed.

  On the other hand, in the case of constant speed traveling, the driver keeps the stepping angle θ constant without applying force to the pedal plate 170 (to be exact, only by the stepping force fg that balances the torque generated by the elastic force of the return spring 160). Can be maintained. Therefore, the degree of fatigue given by driving is reduced.

  Further, when there is no change in the depression amount of the pedal plate 170, the power supply from the inverter circuit to the electronically controlled damper 140 is stopped, and the accelerator pedal device 100 does not generate a braking force. Power consumption can be reduced.

  Furthermore, in a scene where normal driving is performed, the accelerator pedal device 100 is operated when the depression angle θ is between the first critical angle θ1 and the second critical angle θ2, and therefore, the characteristic of the set value freq of the braking force. The rate of increase of the curve does not decrease in that range. For this reason, as the driver depresses the pedal plate 170, the driver feels sensitively the braking force in the direction opposite to the depressing direction and does not perform unnecessary depressing operation.

  Although the accelerator pedal device 100 according to the present embodiment has been described above, the present invention is not limited to the present embodiment, and various modifications can be made within the scope of the technical idea described in the claims. Is possible.

  For example, in this embodiment, the electronically controlled damper is a variable braking mechanism using a rotating electrical machine, but a variable braking mechanism using a magnetorheological fluid may be adopted as the electronically controlled damper. This variable braking mechanism can also generate a braking force similar to the above.

  The magnetorheological fluid is commonly called MRF and is a suspension in which magnetic fine particles are dispersed in the fluid. A magnetorheological fluid has the property that the apparent viscosity decreases when the magnetic field is weak, and the apparent viscosity increases when the magnetic field is strong.

  As an example of a variable braking mechanism using a magnetorheological fluid, a sliding mechanism having a piston and a cylinder, a magnetorheological fluid filled in the sliding mechanism, an orifice communicating with both sides in the sliding direction of the piston, and a magnetorheological Examples include a magnetic field generator that applies a magnetic field to a fluid and a controller that electronically operates the magnetic field generator to control the strength of the magnetic field.

  Since this variable braking mechanism does not generate a magnetic field unless power is applied, the apparent viscosity of the magnetorheological fluid remains unchanged and the sliding resistance of the piston remains low. On the other hand, when electric power is applied, a magnetic field corresponding to this is generated, so that the apparent viscosity of the magnetorheological fluid increases and the sliding resistance of the piston increases.

  This variable braking mechanism is arranged in parallel with the return spring 160, and the piston reciprocates linearly in the cylinder in accordance with the rotation of the pedal arm 110. The variable braking mechanism is supplied with electric power only when the depression angle θ of the pedal arm 110 is increased. When electric power is supplied to the variable braking mechanism, a magnetic field is generated from the magnetic field generator, and the apparent viscosity of the magnetorheological fluid increases. This viscosity increases the sliding resistance of the piston, and a braking force is generated in the reverse direction of the stepping direction. When the depression angle θ is constant, no power is supplied to the variable braking mechanism, so that no braking force is generated.

  As described above, since the action of the variable braking mechanism using the magnetorheological fluid is close to the action of the variable braking mechanism using the rotating electric machine, the same effect as that obtained by the variable braking mechanism using the rotating electric machine is obtained. Will be. In addition, since the variable braking mechanism using the magnetorheological fluid generates a braking force by the continuous operation of the fluid, it causes a motor-specific problem such as torque ripple that can occur in the variable braking mechanism using the rotating electrical machine. And a smooth operation feeling can be given to the driver.

  The accelerator pedal device, which is a variable braking mechanism in which the electronically controlled damper uses a magnetorheological fluid, has a braking force when the pedal plate 170 is depressed, and the braking force decreases when the amount of depression is reduced. 110 immediately returns to the initial position A. Here, in order to determine whether or not it is a scene of depression, it is preferable to detect a change in the depression angle θ.

  Note that a variable braking mechanism using a magnetorheological fluid may be replaced with a variable braking mechanism using an electrorheological fluid. In this case, the viscosity of the fluid can be changed by controlling the electric field applied to the electrorheological fluid.

  FIG. 7 is an exploded perspective view of the accelerator pedal device according to the second embodiment, and FIG. 8 is a perspective view of the same embodiment. As shown in these drawings, the accelerator pedal device 200 according to this embodiment includes a pedal arm 210 that is rotatably installed, a return spring 220 that returns the pedal arm 210 to an initial position, and a pedal arm 210. And an electronically controlled damper 230 that generates a braking force to be applied.

  The pedal arm 210 includes a shaft portion 211, a pedal plate mounting portion 212 that exists in front of the shaft portion 211, and a return spring connection portion 213 that exists in the rear of the shaft portion 211. The shaft portion 211 is formed integrally with the main body of the pedal arm 210. As shown in FIG. 8, the pedal plate 240 is mounted on the pedal plate mounting portion 212.

  One end of a return spring 220 is fixed to the return spring connection portion 213. In this embodiment, a compression coil spring is adopted as the return spring 220. The return spring 220 is compressed by the return spring connecting portion 213 when the pedal arm 210 rotates in the depression direction. Accordingly, the elastic force of the return spring 220 is applied to the return spring connecting portion 213.

  The return spring connection portion 213 is accommodated in the housing. The housing is configured by combining the first member 250 and the second member 260. The first member 250 includes a return spring accommodating portion 251, and the return spring 220 is stored in the return spring accommodating portion 251. The other end of the return spring 220 is in contact with the inner surface of the return spring accommodating portion 251.

  The pedal arm 210 is attached to the first member 250 so that it can rotate within a certain range. Since the pedal arm 210 is connected to the return spring 220, when the pedal arm 210 rotates in the stepping direction, the elastic force of the return spring 220 increases accordingly. The pedal arm 210 is returned to the initial position by this elastic force.

  The pedal plate mounting portion 212 is disposed so as to protrude outward from a rectangular window formed when the first member 250 and the second member 260 are combined. The opening size of the rectangular window is determined according to the operating range of the pedal arm 210.

  The electronically controlled damper 230 is a variable braking mechanism that uses a magnetorheological fluid as a working medium. FIG. 9 is a perspective view of the electronically controlled damper 230, and FIG. 10 is a cross-sectional view showing the internal structure of the electronically controlled damper 230.

  The electronically controlled damper 230 includes a housing 231, a movable body 232, a first inner wall 233, a second inner wall 234, a coil 235, a magnetorheological fluid 236, and a displacement sensor 237.

  The housing 231 includes a main body 231a and a lid 231b. The main body 231a is made of a nonmagnetic material and includes a cylindrical peripheral wall 231c, a disk-shaped end wall 231d that closes one end of the peripheral wall 231c, and a flange 231e that projects outward from the end wall 231d. Yes.

  A first hole 231f, a second hole 231g, and a groove 231h are formed in the end wall 231d. The first hole 231f is formed in the center of the end wall 231d so as to penetrate the end wall 231d. The groove 231h is formed around the first hole 231f so as to communicate with the first hole 231f.

  The flange 231e is formed with a hole 231i through which the fixture 270 is inserted. The lid 231b is made of a nonmagnetic material and is attached to the main body 231a so as to close the other end of the peripheral wall 231c.

  The movable body 232 includes a rotating shaft 232a, a rotor 232b, and a connecting portion 232c. The rotating shaft 232 a is made of a nonmagnetic metal and has a hole 232 d that is coupled to a shaft 211 provided on the pedal arm 210.

  The connecting portion 232c is made of a nonmagnetic metal and is formed integrally with the rotating shaft 232a. The connecting portion 232c is located between the rotating shaft 232a and the rotor 232b and plays a role of connecting both.

  The rotor 232b is made of a soft magnetic material, and includes a cylindrical main body 232e and an end wall 232f that protrudes inward from the end of the main body 232e. The rotor 232b is configured such that an end wall 232f is bonded to the connecting portion 232c and rotates together with the rotation shaft 232a.

  The first inner wall 233 is made of a soft magnetic material, and includes a cylindrical portion 233b having a hole 233a through which the rotating shaft 232a is inserted, and flange portions 233c and 233d projecting outward from both sides of the cylindrical portion 233b. It is configured. The first inner wall 233 is bonded to an end wall 231d constituting the main body 231a of the housing 231.

  The second inner wall 234 is a cylindrical body made of a soft magnetic material. The second inner wall 234 has an outer diameter such that the outer peripheral surface thereof is in contact with the inner peripheral surface of the peripheral wall 231 c constituting the main body 231 a of the housing 231, and the inner peripheral surface is the outer periphery of the first inner wall 233. It has an inner diameter enough to form a predetermined space between the surfaces (the outer peripheral surfaces of the flange portions 233c and 233d).

  The coil 235 is wound around the cylindrical portion 233 b of the first inner wall 233. Connected to the coil 235 is a lead wire 280 for flowing a current through the coil 235.

  The magnetorheological fluid 236 is filled in a space (chamber 238) formed between the first inner wall 233 and the second inner wall 234. The magnetorheological fluid 236 is a suspension in which magnetic particles are dispersed in a fluid such as synthetic oil. The magnetic viscous fluid 236 is a liquid in a state where no magnetic field is applied, but the dispersed particles are connected to each other when a magnetic field is applied to crosslink. A structure is formed, and the shear stress increases in accordance with the magnetic field strength.

  A rotor 232b is disposed in the chamber 238 filled with the magnetorheological fluid 236. In order to prevent leakage of the magnetorheological fluid 236, an O-ring is provided between the lid 231b and the rotation shaft 232a, between the first inner wall 233 and the rotation shaft 232a, and between the first inner wall 233 and the end wall 231d. 239a, 239b, 239c are arranged.

  The displacement sensor 237 detects the rotation angle of the pedal arm 210. In the present embodiment, since the shaft portion 211 and the rotation shaft 232a are coupled and the rotation shaft 232a rotates in conjunction with the rotation of the pedal arm 210, the direct detection target of the displacement sensor 237 is the rotation shaft 232a. Provided.

  That is, the direct detection target of the displacement sensor 237 is a bottom surface 232g of a groove formed in a part of the outer peripheral surface of the rotating shaft 232a. The bottom surface 232g is a curved surface configured such that the distance between the bottom surface 232g and the displacement sensor 237 varies according to the rotation of the rotation shaft 232a.

  More specifically, the bottom surface 232g has a smaller distance between the bottom surface 232g and the displacement sensor 237 according to the rotation of the rotation shaft 232a, for example, when the rotation shaft 232a rotates clockwise in FIG. It is a curved surface.

  In this embodiment, an overcurrent type displacement sensor is used as the displacement sensor 237. The displacement sensor 237 is disposed in the groove 231h formed in the end wall 231d so as to face the bottom surface 232g of the groove formed in the rotation shaft 232a.

  The displacement sensor 237 measures the distance between the bottom surface 232g of the groove and the displacement sensor 237 using a high frequency magnetic field. The distance between the bottom surface 232g of the groove and the displacement sensor 237 changes according to the rotation of the rotation shaft 232a. Since this change is proportional to the displacement of the bottom surface 232g of the groove, the bottom surface 232g of the groove that rotates together with the rotation shaft 232a. Can be detected.

  Since the displacement of the bottom surface 232g of the groove is proportional to the rotational angle of the pedal arm 210, the displacement sensor 237 can detect the rotational angle of the pedal arm 210 by detecting the position of the bottom surface 232g of the groove. . Specifically, since the voltage output from the displacement sensor 237 increases as the depression angle θ of the pedal arm 210 increases, the rotation angle of the pedal arm 210 can be obtained by converting the voltage value into an angle. .

  As shown in FIG. 8, the electronically controlled damper 230 has a housing 231 fixed to the second member 260 using a fixture 270, and a rotating shaft that protrudes from an opening 132 formed in the second member 260. The unit 211 is fixed. Accordingly, the operations of the pedal arm 210 and the cylindrical rotor 232b are interlocked.

  The electronically controlled damper 230 generates a braking force opposite to the direction of rotation of the pedal arm 210. That is, when the pedal arm 210 rotates in the stepping direction, a braking force is generated in the return direction, and when the pedal arm 210 rotates in the return direction, a braking force is generated in the stepping direction. The operation of the electronically controlled damper 230 is controlled by the control device 290.

  The control device 290 includes a substrate 291 on which an electronic circuit is mounted. The substrate 291 is stored in a housing 294 configured to include a lid 292 and a connector 293 that close the opening of the return spring accommodating portion 251. The opening of the housing 294 is closed with a lid 295.

  The control device 290 is attached to the second member 260, and the lead wire 280 is connected to the connector 293. The control device 290 controls the magnitude of the current supplied to the coil 235 based on the rotation angle of the pedal arm 210 detected by the displacement sensor 237, and thereby the magnitude of the braking force exerted by the electronically controlled damper 230. Is controlling.

  The accelerator pedal device 200 configured as described above is set so that the current supplied to the coil 235 of the electronically controlled damper 230 increases as the depression angle of the pedal arm 210 increases.

  When a current is passed through the coil 235, a magnetic field is generated around the coil 235, and the first inner wall 233, the cylindrical rotor 232b, and the second inner wall 234 are magnetized. Further, the magnetic field is applied to the magnetorheological fluid 236, the shear stress of the magnetorheological fluid 236 acting on the cylindrical rotor 232b is increased, and a resistance to reduce the rotational speed of the movable body 232 is generated. Then, this resistance acts as a braking force Fins1 and acts on the pedal arm 210 to apply a load torque T1 to the step of the driver who steps on the pedal plate 240.

  As shown in FIG. 12, the load torque T1 includes not only the braking force fins1 but also the torque T0 generated by the elastic force of the return spring 220. Therefore, the driver must increase the depression angle θ of the pedal arm 210 by applying a pedaling force larger than the load torque T1 to the pedal plate 240 in a scene during acceleration traveling. Therefore, according to the accelerator pedal device 200, it is possible to suppress sudden start and sudden acceleration.

  On the other hand, when the pedal arm 210 rotates in the return direction, the cylindrical rotor 232b of the electronically controlled damper 230 rotates in the reverse direction. At this time as well, current is supplied to the coil 235, and the magnetic viscosity fluid 236 is supplied to the cylindrical rotor 232b. Since the shear stress acts, a resistance that reduces the rotational speed of the movable body 232 is generated. Then, this resistance acts as a braking force fins2 and acts on the pedal arm 210 to apply a load torque T2 to the driver's feet via the pedal plate 240.

  As shown in FIG. 12, the load torque T2 is a torque obtained by subtracting the braking force fins2 from the torque T0 generated by the elastic force of the return spring 220. Therefore, when the pedal plate 240 is depressed and then the pedaling force is relaxed to shift to constant speed running, a load torque T2 smaller than the torque T0 generated by the elastic force of the return spring 220 is applied to the driver's feet. .

  As a result, the driver can keep the depression angle θ constant only by applying a pedaling force that balances the load torque T2 to the pedal plate 170, so that the degree of fatigue imparted by the driving is further reduced.

  As described above, the accelerator pedal device 200 according to this embodiment is a rotary variable braking mechanism in which an electronically controlled damper uses a magnetorheological fluid as a working medium. Such an electronically controlled damper can generate high torque even when it is small. For example, according to this electronically controlled damper, it is possible to obtain an output torque of 2 N · m even when the outer diameter of the housing is about 40 mm and the height of the housing is about 20 mm. It is difficult to obtain an output torque of 2 N · m even with a size more than twice that.

  In this embodiment, by reducing the thickness of the cylindrical rotor 232b (reducing the difference between the outer diameter and the inner diameter), not only the first inner wall 233 and the cylindrical rotor 232b but also the second inner wall 234 are magnetic. It is comprised so that a path | route may be comprised. Therefore, the electronically controlled damper 230 employed in the present embodiment is not limited to the inner peripheral surface of the cylindrical rotor 232b, but the shear stress of the magnetorheological fluid 236 acts on the outer peripheral surface of the cylindrical rotor 232b. A braking force larger than the configuration in which the shear stress of the magnetorheological fluid acts only on the inner peripheral surface of the rotor can be generated.

  In addition, the electronically controlled damper 230 employed in the present embodiment has a configuration in which the movable body 232 is directly connected to the shaft portion 211 of the pedal arm 210, so that the configuration for transmitting torque to the pedal arm 210 is extremely simple. Therefore, it is possible to reduce the size of the apparatus.

  Further, in addition to the simple configuration for transmitting the braking force, the response of the magnetorheological fluid is several ms, so that the braking force corresponding to the behavior of the pedal arm 210 can be generated quickly. Therefore, the accelerator pedal device according to the present embodiment contributes to an improvement in operational feeling.

DESCRIPTION OF SYMBOLS 100 Accelerator pedal apparatus 110 Pedal arm 111 Pedal plate mounting part 112 Return spring connection part 113 Bearing storage part 120 1st member 121 Return spring accommodating part 122 Window opening part 123 Sliding shaft 124 Pedal arm accommodating part 130 Second member 131 Window opening Part 132 Opening part 133 Through hole 134 Pedal arm housing part 140 Electronically controlled damper 140a Rotation variable resistance 140b Current detection part 150 Control device 150a Braking force setting part 150b Subtraction part 150c Feedback control part 150d PWM signal generation part 150e Braking force calculation part 151 Housing 151a Lid 151b Connector 152 Circuit board 153 Lid 160 Return spring 170 Pedal plate 200 Accelerator pedal device 210 Pedal arm 211 Shaft 2 2 Pedal plate mounting part 213 Return spring connecting part 220 Return spring 230 Electronically controlled damper 231 Housing 231a Housing body 231b Lid 231c Peripheral wall 231d End wall 231e Flange 231f First hole 231g Second hole 231h Groove 231i Hole 232 Movable body 232 232a Rotating shaft 232b Rotor 232c Connection portion 232d Hole portion 232e Rotor body 232f End wall 232g Bottom surface of groove 233 First inner wall 233a Hole 233b Tube portion 233c, 233d Flange portion 234 Second inner wall 235 Coil 236 Magnetorheological fluid 237 Displacement Sensor 238 Chamber 239a, 239b, 239c O-ring 240 Pedal plate 250 First member 251 Return spring accommodating portion 260 Second member 261 Mouth 270 the fixture 280 lead 290 controller 291 board 292 lid 293 Connector 294 housing 295 lid
A Initial position fa Lower limit value of braking force fb Upper limit value of braking force fg Treading force θ Depression angle fins Braking force fm Reaction force freq Setting value of braking force iDM Operation mode information S-mode Sports mode C-mode Normal mode E-mode Environment Protection mode θ1 First critical angle θ2 Second critical angle T0 Torque generated by elastic force of return spring T1 Load torque during acceleration travel T2 Load torque during constant speed travel

  The problem to be solved by the present invention is to provide an accelerator pedal device that contributes to improved power consumption and improved drivability.

In order to solve the above problems, the present invention provides the following accelerator pedal device.
1. A mechanism that converts a pedaling force into a stepping torque via a pedal arm, an electronically controlled damper that generates a braking force in a direction opposite to the stepping direction of the pedal arm, and a magnitude of the braking force that applies electric power to the electronically controlled damper And an electronically controlled damper that generates the braking force only when a depression angle of the pedal arm is increased.
2. 2. The accelerator pedal device according to 1 above, wherein the electronically controlled damper is a variable braking mechanism using a rotating electric machine including a rotor and a stator.
3. 2. The accelerator pedal device according to 1, wherein the electronically controlled damper is a variable braking mechanism using a magnetorheological fluid or an electrorheological fluid.
4). 2. The accelerator pedal device according to claim 1, wherein the control device determines a set value of the braking force based on the depression angle.
5. The control device is configured to set the stepping angle from the first critical angle at which the stepping angle starts to increase to the second critical angle that is set below the inflection point of the setting value. 5. The accelerator pedal device as described in 4 above, wherein the rate of increase of the value is continuously increased.

  According to the first to fifth aspects of the present invention, the braking force acts in the direction opposite to the depression direction only when the depression angle of the pedal arm is increased.

Therefore, when there is no change in the amount of depression, no braking force is generated, so that the power consumption of the electronically controlled damper can be suppressed. In addition, in a scene during constant speed traveling, no braking force is applied to the driver's feet, which contributes to suppressing the driver's fatigue .

Claims (9)

  A mechanism that converts a pedaling force into a stepping torque via a pedal arm, an electronically controlled damper that generates a braking force in a direction opposite to the stepping direction of the pedal arm, and a magnitude of the braking force that applies electric power to the electronically controlled damper And an electronically controlled damper that generates the braking force only when a depression angle of the pedal arm is increased.   The accelerator pedal device according to claim 1, wherein the electronically controlled damper is a variable braking mechanism using a rotating electric machine including a rotor and a stator.   The accelerator pedal device according to claim 1, wherein the electronically controlled damper is a variable braking mechanism using a magnetorheological fluid or an electrorheological fluid.   The accelerator pedal device according to any one of claims 1 to 3, wherein the control device determines a set value of the braking force based on the depression angle.   The control device is configured to set the stepping angle from the first critical angle at which the stepping angle starts to increase to the second critical angle that is set below the inflection point of the setting value. 5. The accelerator pedal device according to claim 4, wherein the rate of increase of the value is continuously increased.   A pedal arm that is rotatably installed; a return spring that returns the pedal arm to an initial position; and an electronically controlled damper that generates a braking force that acts on the pedal arm, the electronically controlled damper comprising: An accelerator pedal device comprising a rotary variable braking mechanism using a magnetorheological fluid as a working medium.   The accelerator pedal device according to claim 6, wherein the electronically controlled damper is configured to generate a braking force opposite to a rotation direction of the pedal arm.   The electronically controlled damper includes a chamber filled with the magnetorheological fluid, and a cylindrical rotor rotatable in the chamber, and shear stress of the magnetorheological fluid causes an outer peripheral surface and an inner periphery of the cylindrical rotor. The accelerator pedal device according to claim 6, wherein the accelerator pedal device is configured to act on a surface.   The accelerator pedal device according to claim 6, wherein the electronically controlled damper includes a displacement sensor capable of detecting a rotation angle of the pedal arm.

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