JP2000280872A - Stroke simulator - Google Patents

Abstract

(57) [Summary] [PROBLEMS] The invention can be applied to a brake device that does not use hydraulic pressure, and can provide a driver with a good operational feeling.
Furthermore, we provide a stroke simulator that can reduce the space required for related equipment. SOLUTION: The brake pedal 13 is connected to a brake pedal 13 to give a reaction force to the operation of the brake pedal 13, does not require a hydraulic pressure, and can finely control a reaction force characteristic, and further has a brake. A reaction force is applied to the brake pedal 13 by electric actuators 19 and 20 that can electrically detect the operation amount of the pedal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stroke simulator for applying a reaction force to a brake pedal for the operation thereof.

[0002]

2. Description of the Related Art In recent years, a brake pedal and a braking force generator independent of the brake pedal have been provided, and the operation amount of the brake pedal has been electrically detected, and the braking force generation device has been detected in accordance with the operation amount. A vehicle brake device that generates a braking force by controlling the braking force has been developed. As a braking force generating device of such a brake device, there are a device that generates a braking force by a brake fluid pressure generated by a pump and a device that generates a braking force by an electric actuator. By the way, even in the above-described brake device, if the driver does not give the same operation feeling to the operation of the brake pedal as the conventional brake device, the driver will feel uncomfortable. In order to give such a feeling of operation to the driver, a stroke simulator which is connected to a brake pedal and applies a reaction force to the operation of the brake pedal is used. Conventional stroke simulators include a piston and a spring that absorb the hydraulic pressure generated by a master cylinder connected to a brake pedal, and apply a reaction force to the brake pedal with this spring. There is a type in which a spring is provided on the input rod, and the spring applies a reaction force to the brake pedal.

[0003]

The former stroke simulator can be applied to a brake device using hydraulic pressure, but cannot be applied to a brake device not using hydraulic pressure. Further, the relationship between the stroke of the brake pedal and the pedaling force is generally non-linear, and there are hysteresis and invalid input, and the reaction force characteristics of the brake pedal are complicated. It is difficult to reproduce this characteristic using only an elastic body such as a spring, and there is a problem that a conventional stroke simulator cannot provide a driver with a good operational feeling. Furthermore, since the conventional stroke simulator is connected to at least one of a stroke sensor and a pedaling force sensor for detecting the operation amount of the brake pedal, a space for the related equipment is increased.

[0004] The present invention can be applied to a brake device that does not use hydraulic pressure, can provide a driver with a good operational feeling, and can provide a stroke simulator that can reduce the space required for related equipment. Aim.

[0005]

To achieve the above object, a stroke simulator according to a first aspect of the present invention is connected to a brake pedal and applies a reaction force to the operation of the brake pedal. A reaction force is applied to the brake pedal by an electric actuator. As described above, the reaction force is applied to the brake pedal by the electric actuator, so that the hydraulic pressure is not required, the reaction force characteristics can be finely controlled, and the operation amount of the brake pedal is electrically controlled by the electric actuator. Since it is possible to perform the detection, a separate sensor can be omitted.

According to a second aspect of the present invention, in the stroke simulator, a stroke is applied to the brake pedal by the electric actuator. As described above, since the stroke is applied to the brake pedal by the electric actuator, the stroke characteristics of the brake pedal can be finely controlled.

According to a third aspect of the present invention, there is provided a stroke simulator according to the first or second aspect, wherein the operation amount of the brake pedal is detected by the electric actuator. As described above, since the operation amount of the brake pedal can be detected by the electric actuator, a separate sensor is not required.

According to a fourth aspect of the present invention, in the stroke simulator according to the third aspect, at least one of an operation force and an operation stroke is detected as the operation amount. in this way,
Since the electric actuator detects at least one of the operation force and the operation stroke as the operation amount of the brake pedal, a separate sensor for detecting this is unnecessary.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A stroke simulator according to a first embodiment of the present invention will be described below with reference to FIGS. FIG. 1 shows a brake input unit 11 provided with a stroke simulator 10 according to the first embodiment.

The brake input unit 11 is a brake pedal 13 having a pedal unit 12 which is depressed by a driver.
A rotating shaft 14 fixed to the brake pedal 13, a pair of supporting members 16 and 16 for rotatably supporting the rotating shaft 14 of the brake pedal 13 on a vehicle body 15 of the vehicle, and a brake connected to the brake pedal 13. The stroke simulator 10 according to the first embodiment for applying a reaction force to the operation of the pedal 13 is provided.

The stroke simulator 10 includes a rotating shaft 1
There is provided a speed reducer 18 for connecting the drive gear 4 to one side of the drive transmission system, and the speed reducer 18 is supported by one support member 16. In addition, the stroke simulator 10
A rotary motor (electric actuator) 19 having a motor shaft (not shown) is provided. In the rotary motor 19, a motor shaft is rotated by electric power, and the motor shaft is connected to an opposite side in a drive transmission system of the speed reducer 18. Here, the speed reducer 18 is a rotary shaft 14 of the brake pedal 13.
Is reduced at a predetermined reduction ratio and transmitted to a motor shaft (not shown) of the rotary motor 19.

Further, the stroke simulator 10 includes:
The rotary motor 19 has a rotary encoder (electric actuator) 20 for detecting a rotation position of a motor shaft (not shown). Further, the stroke simulator 10 includes a return spring 22 for urging the brake pedal 13 in one direction, a stopper 23 for restricting the rotation of the brake pedal 13, and a brake pedal switch 24 operated by the rotation of the brake pedal 13. are doing.

The return spring 22 is interposed between a shaft 25 fixed to an upper portion of the brake pedal 13 and the vehicle body 15, and the upper portion of the brake pedal 13 is
5 (the counterclockwise direction in FIG. 1A).

The stopper 23 extends from the vehicle body 15 so as to approach the upper end of the brake pedal 13. The brake pedal switch 24 is attached to the tip of the stopper 23. This brake pedal switch 24
Indicates that the brake pedal 13 is located at the limit position on the stopper 23 side by the biasing force of the return spring 22 and is in the initial position where the rotation thereof is restricted, or the brake pedal 13 is separated from the stopper 23 by the depression of the brake pedal 13. Is detected, and the result is output. The brake pedal switch 24 is set to be turned off when the brake pedal 13 is at the initial position, and turned on when the brake pedal 13 is rotated very slightly.

In addition, the stroke simulator 10
It has a controller 27 that controls the rotary motor 19 based on the output from the brake pedal switch 24 and the rotary encoder 20.

The operation of the stroke simulator 10 according to the first embodiment will be described. First, when the brake pedal 13 is at the initial position where it is not depressed, the brake pedal 13 is in contact with the stopper 23 by the urging force of the return spring 22. At this time, since the brake pedal switch 24 is in the OFF state, the controller 27 of the stroke simulator 10
Is in the initial position, and the rotation motor 19 is turned off.
FF is performed and no torque is generated.

In this state, when the driver depresses the pedal portion 12 of the brake pedal 13 and makes a stroke, the brake pedal 13 is moved in a predetermined direction (clockwise direction in FIG. 1A) against the urging force of the return spring 22. ) To rotate. Here, when the brake pedal 13 rotates very slightly and separates from the stopper 23, the brake pedal switch 24 provided at the tip of the stopper 23 is turned ON. ON of this brake pedal switch 24
Based on the operation, the controller 27 starts position control of the rotary motor 19.

That is, when the brake pedal 13 is rotated while the pedal portion 12 is being stroked, the rotation shaft 14 of the brake pedal 13 is rotated, and the rotation motor 19 is driven through a speed reducer 18 connected to the rotation shaft 14. A motor shaft (not shown) is rotated. The controller 27 calculates the torque required for the rotary motor 19 based on the output from the rotary encoder 20 that detects the rotational position of the motor shaft,
A signal is output to the rotation motor 19 to generate a necessary torque. In this way, a reaction force to the brake pedal 13 is generated in the stroke simulator 10.

Here, the control contents of the controller 27 of the stroke simulator 10 according to the first embodiment will be described in more detail with reference to the flowcharts shown in FIGS. The controller 27 determines whether or not the driver has depressed the brake pedal 13 by using the brake pedal switch 24.
(Step SA1). When the brake pedal 13 is at the initial position and the brake pedal switch 24 is OFF, the controller 27 does not control the position of the rotary motor 19 (step SA2). That is, the power supply to the rotary motor 19 is turned off.

On the other hand, in step SA1, when the brake pedal switch 24 is ON, the controller 27
Performs position control to control the rotation position of the motor shaft (not shown) of the rotation motor 19 to a predetermined position (step SA3). The rotary motor 19 is provided with a rotary encoder 20 for detecting the rotation position of the motor shaft, and can detect the rotation position of the motor shaft. Further, the rotational position of the motor shaft and the pedal portion 12 of the brake pedal 13 are determined.
The stroke position of the brake pedal 13 (operation amount, operation stroke) can be detected from the detection result of the rotary encoder 20 because the stroke position corresponds to the stroke position of the brake pedal 13.

The predetermined position immediately after the brake pedal switch 24 is turned on is a position where the pedal portion 12 of the brake pedal 13 slightly strokes and the brake pedal switch 24 is turned on. Here, step SA
3, the position control is performed as shown in the flowchart of FIG.
It is determined whether or not the current rotation position of the motor shaft (not shown) is at a predetermined position (step SS1). If the current rotation position of the motor shaft is at the predetermined position, the position of the motor shaft is held (step SS1). SS2).

On the other hand, if the position of the motor shaft is not at the predetermined position in step SS1, it is determined whether or not the current rotational position of the motor shaft (not shown) exceeds the predetermined position (step SS3). If the current rotational position of the shaft is beyond the predetermined position, the motor shaft is rotated in the reverse direction, that is, retracted (step SS4). On the other hand, if the current position of the motor shaft does not exceed the predetermined position in step SS3, the motor shaft is rotated forward, that is, forward (step SS5).

As described above, when the position control for controlling the rotation position of the motor shaft (not shown) of the rotary motor 19 to the predetermined position is performed in step SA3, the position control of the motor shaft in step SA3 is necessary. The obtained current value is set as a variable A (step SA4).

Then, the driver's pedaling force (operation amount, operation force)
F is obtained as a function of the variable A (step SA5). That is, in general, the relationship between the torque of the rotary motor 19 and the current value is in a proportional relationship, and the relationship between the driver's pedaling force F and the variable A, as shown in FIG.
Are proportional to each other. Therefore, the pedaling force F is obtained from the variable A based on this relationship.

Further, a predetermined position X which is a target value of the position of the motor shaft (not shown) is obtained as a function of the pedaling force F (step SA6). That is, in general, the pedal stroke and the pedaling force vary from vehicle to vehicle and have non-linear characteristics, but can be approximated and functioned. As shown in FIG. 5, the relationship between the predetermined position X and the pedaling force F is such that as the pedaling force F increases, the predetermined position X increases. Therefore,
The predetermined position X is obtained from the pedaling force F based on this relationship. Then, in the position control in step SA3 of the next control cycle, the rotational position of the motor shaft of the rotary motor 19 is set to the predetermined position X.
The control is performed so that

According to the stroke simulator 10 of the first embodiment described above, the rotary motor 19, which is an electric actuator, applies a reaction force and a stroke to the brake pedal 13, so that no hydraulic pressure is required. In addition, the reaction force characteristic and the stroke characteristic can be finely controlled, and the operation amount of the brake pedal 13 can be electrically detected by the rotary encoder 20 required for controlling the rotary motor 19, so that a separate sensor is not required. Can be. Therefore, the present invention can be applied to a brake device that does not use a hydraulic pressure, can provide a driver with a good operational feeling, and can reduce the space required for related devices.

Next, a stroke simulator 10 according to a second embodiment of the present invention will be described below mainly with reference to FIGS. 6 to 8, focusing on differences from the first embodiment.
The same parts as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted. The stroke simulator 10 according to the second embodiment includes a return spring 22 for urging the brake pedal 13 in one direction, a stopper 23 for restricting the rotation of the brake pedal 13, and a brake pedal operated by the rotation of the brake pedal 13. No switch 24 is provided.

The operation of the stroke simulator 10 according to the second embodiment is substantially the same as that of the first embodiment, but the rotary motor 19 operates even when the brake pedal 13 is not depressed. Position control is performed so that the brake pedal 13 is located at the initial position.

Here, the control contents of the controller 27 of the stroke simulator 10 according to the second embodiment will be described in more detail with reference to the flowchart shown in FIG. The controller 27 performs position control for controlling the rotation position of the motor shaft (not shown) of the rotation motor 19 to be a predetermined position (step SB1). The first predetermined position when the brake pedal 13 is depressed is:
When the driver starts to depress the brake pedal 13, the position is set to a position where no trouble is caused. Here, the position control in step SB1 has the contents of steps SS1 to SS5 shown in the flowchart of FIG. 3, as in step SA3 of the first embodiment.

In step SB1, the rotation motor 19
When the position control for controlling the rotation position of the motor shaft (not shown) to be a predetermined position is performed, the current value required for the position control of the motor shaft in step SB1 is set as a variable A (step SB2). Then, the driver's treading force F is set to a variable A
(Step SB3). That is, similarly to step SA5 in the first embodiment, the pedaling force F is obtained from the variable A based on the relationship shown in FIG.

Further, a predetermined position X which is a target value of the position of the motor shaft (not shown) is obtained as a function of the pedaling force F (step SB4). That is, step S of the first embodiment
Similarly to A6, the predetermined position X is obtained from the pedaling force F based on the relationship shown in FIG. Then, control is performed so that the rotation position of the motor shaft of the rotation motor 19 becomes the predetermined position X in the position control in step SB1 of the next control cycle. In step SB4, when the predetermined position X which is the target value of the position of the motor shaft is obtained as a function of the pedaling force F, if the predetermined position X shown in FIG. Only a reaction force can be applied to the brake pedal 13.

In the first and second embodiments, the case where the separate reduction gear 18 and the rotary motor 19 are connected has been described as an example. However, as shown in FIG. 9, the planetary gear mechanism is rotated. By incorporating them in the motor, it is also possible to incorporate them integrally.

That is, the speed reducer 18 and the rotary motor 1
9, a support member 32 to which the rotating shaft 14 of the brake pedal 13 is connected to the casing 31;
A plurality of planetary gears 33 rotatably supported by the two
A sun gear 34 meshed with the inside of the planetary gears 33 and fixed to the casing 31; a ring gear 35 meshed with the outsides of the plurality of planetary gears 33 and serving as a rotor; and a stator 36 provided inside the casing 31. A rotary motor (electric actuator) 37 with a built-in speed reducer having the following. Here, the support member 32, the planetary gear 33, the sun gear 3
4 and the ring gear 35 constitute a planetary gear mechanism 38.

Next, a stroke simulator 10 according to a third embodiment of the present invention will be described mainly with reference to FIG.
The following description focuses on the differences from the first embodiment. The same parts as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted. The stroke simulator 10 according to the third embodiment uses a linear motor (electric actuator) 40 instead of the speed reducer 18 and the rotary motor 19 according to the first embodiment.
Instead of 0, a position detector (electric actuator) 41 is used.

That is, the stroke simulator 10 of the third embodiment has a linear motor 40 attached to the vehicle body 15 in a state disposed between the support member 16 and the return spring 22. The linear motor 40 has a slide member 42 which moves forward and backward by electric power.
The tip of the slide member 42 is connected to a position between the rotation shaft 14 of the brake pedal 13 and the return spring 22 via a connection member 43.

The stroke simulator 10 according to the third embodiment includes a brake pedal 1 of a linear motor 40.
It has a position detector 41 attached to the third side to detect the position of the slide member 42.

The control contents of the controller 27 of the stroke simulator 10 according to the third embodiment are as follows. The rotary motor 19 of the first embodiment is replaced with a linear motor 40, and the motor shaft is replaced with a slide member 42. Further, the rotation position of the motor shaft is changed to the slide position of the slide member 42, the rotary encoder 20 is changed to the position detector 41,
The reverse rotation is replaced by the backward rotation, and the forward rotation is replaced by the forward rotation.

Next, a stroke simulator 10 according to a fourth embodiment of the present invention will be described mainly with reference to FIG.
The following description focuses on the differences from the second embodiment. The same parts as those in the second embodiment are denoted by the same reference numerals, and description thereof will be omitted. The stroke simulator 10 according to the fourth embodiment uses a linear motor (electric actuator) 40 instead of the speed reducer 18 and the rotary motor 19 according to the second embodiment, and uses the rotary encoder 20 instead. The position detector 41 is used.

That is, the stroke simulator 10 according to the fourth embodiment has a linear motor 40 mounted on the vehicle body 15 in a state of being disposed above the support member 16. The linear motor 40 has a slide member 42 that moves forward and backward by electric power. The tip of the slide member 42 is connected to a position above the rotation shaft 14 of the brake pedal 13 via a connection member 43.

The stroke simulator 10 according to the fourth embodiment includes a brake pedal 1 of a linear motor 40.
It has a position detector 41 attached to the third side to detect the position of the slide member 42.

The control contents of the controller 27 of the stroke simulator 10 according to the fourth embodiment are as follows. The rotary motor 19 according to the second embodiment is replaced with a linear motor 40, and the motor shaft is replaced with a slide member 42. Further, the rotation position of the motor shaft is changed to the slide position of the slide member 42, the rotary encoder 20 is changed to the position detector 41,
The reverse rotation is replaced by the backward rotation, and the forward rotation is replaced by the forward rotation.

Next, a stroke simulator 10 according to a fifth embodiment of the present invention will be described mainly with reference to FIG.
The following description focuses on the differences from the third embodiment. The same parts as those in the third embodiment are denoted by the same reference numerals, and description thereof is omitted. The stroke simulator 10 according to the fifth embodiment differs from the third embodiment in the mounting position of the linear motor 40.

That is, the stroke simulator 10 according to the fifth embodiment has a linear motor 40 attached to the vehicle body 15 in a state where it is disposed below the support member 16. The slide member 42 of the linear motor 40
Is connected to the brake pedal 13 via the connecting member 43.
Is connected between the rotary shaft 14 and the pedal section 12. The control content of the controller 27 of the stroke simulator 10 according to the fifth embodiment is different from that of the third embodiment in that the forward and backward movements of the slide member 42 are reversed.

Next, a stroke simulator 10 according to a sixth embodiment of the present invention will be described mainly with reference to FIG.
The following description focuses on the differences from the fourth embodiment. The same parts as those of the fourth embodiment are denoted by the same reference numerals, and the description is omitted. The stroke simulator 10 according to the sixth embodiment differs from the fourth embodiment in the mounting position of the linear motor 40.

That is, the stroke simulator 10 according to the sixth embodiment has a linear motor 40 mounted on the vehicle body 15 in a state where it is disposed below the support member 16. The slide member 42 of the linear motor 40
Is connected to the brake pedal 13 via the connecting member 43.
Is connected between the rotary shaft 14 and the pedal section 12. The control contents of the controller 27 of the stroke simulator 10 according to the sixth embodiment are different from the fourth embodiment in that the forward and backward movements of the slide member 42 are reversed.

Next, a stroke simulator 10 according to a seventh embodiment of the present invention will be described mainly with reference to FIG.
The following description focuses on the differences from the sixth embodiment. The same parts as those in the sixth embodiment are denoted by the same reference numerals, and description thereof is omitted. The stroke simulator 10 according to the seventh embodiment has a further simplified structure as compared with the sixth embodiment.

In the stroke simulator 10 according to the seventh embodiment, a linear motor 40 is mounted on a vehicle body 15 so that a slide member 42 extends obliquely upward through a mounting member 44. The pedal section 12 is directly fixed to the tip of the slide member 42. The control content of the controller 27 of the stroke simulator 10 according to the seventh embodiment is the same as that of the sixth embodiment.

In the third to seventh embodiments, the case where the linear motor 40 is used has been described as an example. Instead of the linear motor 40, the slide of the slide member 42 is performed as shown in FIG. It is also possible to use a slide rotation conversion motor (electric actuator) 46 that converts the rotation into a rotation by a ball screw mechanism 45.

That is, the slide rotation conversion motor 4
6 is a casing 47, a slide member 42 on which a male screw portion 51 is formed, and a male screw portion 51 of the slide member 42.
Member 4 having a female thread (not shown) facing the
8, a ball (not shown) inserted into the groove between the male screw part 51 and the female screw part, a rotor 49 fixed to the outside of the nut member 48, and a stator 50 provided inside the casing 47. are doing.

[0050]

As described in detail above, claim 1 of the present invention
According to the stroke simulator described above, since a reaction force is applied to the brake pedal by the electric actuator, no hydraulic pressure is required, the reaction force characteristics can be finely controlled, and the operation amount of the brake pedal can be reduced. Since electric detection can be performed by the electric actuator, a separate sensor can be omitted. Therefore,
In addition to being applicable to a brake device that does not use hydraulic pressure, it is possible to give the driver a good operational feeling, and furthermore, it is possible to reduce the space required for related devices.

According to the stroke simulator of the second aspect of the present invention, since the stroke is applied to the brake pedal by the electric actuator, the stroke characteristics of the brake pedal can also be finely controlled. Therefore, it is possible to give the driver a better operational feeling.

According to the stroke simulator of the third aspect of the present invention, since the operation amount of the brake pedal can be detected by the electric actuator, a separate sensor is not required. Therefore, the space combined with the related equipment can be reduced.

According to the stroke simulator of the present invention, since the electric actuator detects at least one of the operation force and the operation stroke as the operation amount of the brake pedal, this is detected. No separate sensor is required. Therefore, the space combined with the related equipment can be reduced.

[Brief description of the drawings]

FIG. 1 shows a brake input unit in which a stroke simulator according to a first embodiment of the present invention is used.
(A) is a side view, (b) is a front view.

FIG. 2 is a flowchart showing the entire control contents of a controller of the stroke simulator according to the first embodiment of the present invention.

FIG. 3 is a flowchart showing control contents of position control of a controller of the stroke simulator according to the first embodiment of the present invention.

FIG. 4 is a characteristic diagram illustrating an example of a relationship between a variable A and a pedaling force F stored as a map in a controller of the stroke simulator according to the first embodiment of the present invention.

FIG. 5 is a characteristic diagram illustrating an example of a relationship between a pedaling force F and a predetermined position X stored as a map in a controller of the stroke simulator according to the first embodiment of the present invention.

FIG. 6 shows a brake input unit in which the stroke simulator according to the second embodiment of the present invention is used.
(A) is a side view, (b) is a front view.

FIG. 7 is a flowchart showing the entire control contents of a controller of a stroke simulator according to a second embodiment of the present invention.

FIG. 8 is a characteristic diagram illustrating another example of the relationship between the pedaling force F and the predetermined position X stored as a map in the controller of the stroke simulator according to the second embodiment of the present invention.

FIG. 9 is a side sectional view showing a motor with a built-in speed reducer that can be used in place of the speed reducer and the rotary motor of the stroke simulator according to the first and second embodiments of the present invention.

FIG. 10 shows a brake input unit in which the stroke simulator according to the third embodiment of the present invention is used.
(A) is a side view, (b) is a front view.

FIG. 11 shows a brake input unit in which a stroke simulator according to a fourth embodiment of the present invention is used.
(A) is a side view, (b) is a front view.

FIG. 12 shows a brake input unit in which a stroke simulator according to a fifth embodiment of the present invention is used.
(A) is a side view, (b) is a front view.

FIG. 13 shows a brake input unit using a stroke simulator according to a sixth embodiment of the present invention;
(A) is a side view, (b) is a front view.

FIG. 14 is a side view showing a brake input unit using a stroke simulator according to a seventh embodiment of the present invention.

FIG. 15 is a side sectional view showing a slide rotation conversion motor that can be used in place of the linear motor of the stroke simulator according to the third to seventh embodiments of the present invention.

[Explanation of symbols]

 Reference Signs List 10 stroke simulator 13 brake pedal 19 rotary motor (electric actuator) 20 rotary encoder (electric actuator) 37 rotary motor with built-in reduction gear (electric actuator) 40 linear motor (electric actuator) 41 position detector (electric actuator) 46 slide rotation conversion Motor (electric actuator)

Claims (4)

[Claims] 1. A stroke simulator which is connected to a brake pedal and applies a reaction force to the brake pedal for the operation thereof, wherein a reaction force is applied to the brake pedal by an electric actuator. 2. The stroke simulator according to claim 1, wherein a stroke is applied to the brake pedal by the electric actuator. 3. The stroke simulator according to claim 1, wherein the operation amount of the brake pedal is detected by the electric actuator. 4. The stroke simulator according to claim 3, wherein at least one of an operation force and an operation stroke is detected as the operation amount.