JP2013142445A - Electric brake device and assisting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small and lightweight brake device capable of making a reliable braking force adjustment.SOLUTION: A brake pad 18, a dielectric elastomer actuator 1, and a pressure sensor 19 are arranged inside the brake device 10. The pressure sensor 19 is embedded and fixed in a bottom part inside a case 11, in a position of a fixed part 7, and its surface coincides with the surface of the bottom part. The dielectric elastomer actuator 1 is arranged in such a direction that the electrode surfaces of flexible electrodes 3, 4 arranged on both faces of the actuator are parallel with the bottom part of the case 11. The dielectric elastomer actuator 1 is fixed to the case 11 through the pressure sensor 19 at the fixed part 7 abutting on the pressure sensor 19 fixed to the case 11. The brake pad 18 side is provided with a fixing part 20 for fixing the brake pad 18 and the dielectric elastomer actuator 1. Normal reaction is monitored by the pressure sensor 19 to control voltage applied to the flexible electrodes 3, 4 to thereby apply an accurate braking force to a belt-like moving body 14.

Description

  The present invention relates to an electric brake device, and more particularly to a brake technology applied to an assist device used for assisting human operation and work.

  In order to assist the muscular strength of the elderly and the disabled whose muscle strength has declined, instruments and devices that are worn on a person and assist the force have been developed. Such instruments and devices can be used not only for people whose muscle strength has declined, but also for healthy people who perform work that places a burden on muscles, in order to reduce the work. As the simplest auxiliary device, there is a device that uses a supporter or a rubber belt to obtain an auxiliary force in the same direction as the muscle. However, in the case of using such a passive force, a force is always applied to the wearer, and an operation other than the target work is hindered, or the magnitude of the force is determined depending on the posture. Therefore, there is a muscular strength assist device using an electric actuator in order to provide a more appropriate assist force.

  For example, as described in Patent Document 1, an electric motor is disposed at a joint position of a frame to be worn on the lower limb, and operates so as to change the angles of knees and hip joints. With such a device, since a large output is possible, the effect of assisting muscle strength is sufficient. On the other hand, since the electric motor is heavy, the frame is also robust, so that it is heavy to wear as a whole.

  On the other hand, a brake using an electroactive polymer expected as a lightweight actuator has also been proposed. In order to generate a frictional force, an actuator made of an electroactive polymer has a configuration in which a brake pad, which is a friction material, is pressed against a moving body that operates. An electroactive polymer is a material that changes its shape by electrical stimulation. An actuator made of an electroactive polymer uses deformation of this material as an actuator. Known electroactive polymers include those made of conductive polymers, ionic conductive polymers, gels, and dielectric elastomers. Among these, it is known that an actuator using a dielectric elastomer has high response speed, deformation, generated stress, and energy conversion efficiency (see Non-Patent Document 1 and Non-Patent Document 2). As a brake using this dielectric elastomer, it is used in a vehicle brake (see Patent Document 2) that can obtain a sufficient braking force with a small size and high efficiency, and a tactile device that gives a tactile sense by presenting the braking force. (See Patent Document 3).

WO2009 / 081710 Japanese Patent No. 4068013 Special table 2003-534620 gazette

Science 287, 5454, 836 (2000) Macromolecule Rapid Communication No.31, p. 10 (2010)

  In the case of the device described in Patent Document 1, since a large output is possible, the effect of assisting muscle strength is sufficient, but there is a problem that it becomes heavy to wear as a whole. In addition, since the motor is a rotational output, there is a possibility of affecting the wearer's body when the motor runs away and continues to rotate or when the output is too large.

  On the other hand, although the application of muscle strength assistance is less than the device that actively assists muscle strength using a motor, the muscle strength assistance device using an electric speed reducer does not apply excessive force to the wearer, and more It can be used safely. Such devices are expected to be particularly effective as an aid to muscle strength to support the body against gravity. For example, a person whose muscle strength around the knee has weakened cannot fully support his / her own weight with his / her own muscle strength when the stairs are lowered, and the speed at which the foot is landed cannot be sufficiently reduced. For this reason, when landing, an impact is applied to the foot, causing the knee to hurt. Therefore, if there is something like a muscular strength assisting device using a speed reducer, it can be assisted to slowly lower the foot.

  It is essential that the electric brake for such a use is lightweight in consideration of wearing. The basic function of the brake is to apply a negative force to the moving body that operates and brake the movement. Types of force include (1) frictional force, (2) fluid resistance, and (3) electromagnetic force. The most common is a brake that uses the frictional force (1), and a frictional force is generated by pressing a brake pad, which is a friction material, against the moving body. There are hydraulic, mechanical and electromagnetic methods for pressing the brake pads. Although the hydraulic type is strong, piping is necessary and responsiveness is poor. The mechanical type has a large number of parts, resulting in an increase in weight. Since the electromagnetic type uses an electromagnet, the coil weight is large and heavy. In the brake using the resistance force of the fluid (2), a special liquid such as a magnetic fluid or an electrorheological fluid in which the viscosity of the fluid changes electrically is used. Although there is an advantage that a brake can be configured with a small system, many use a liquid in which fine particles are dispersed as a fluid, and there is a possibility of performance change due to precipitation or aggregation of fine particles. Moreover, since the liquid is sealed and used, problems such as liquid leakage can be considered. In the brake using the electromagnetic force of (3), the force due to the eddy current is used, but the structure of the device becomes large and is not suitable for mounting use.

  In the brake structures proposed in Patent Documents 2 and 3, the electroactive polymer is deformed by applying an electric signal, and the friction material is pressed against the braking body by the deformation to be braked. However, the physical properties of the electroactive polymer change due to heat generated by friction. Elastomers and resins that are electroactive polymer materials have a higher coefficient of thermal expansion than materials such as metals and ceramics. Moreover, the temperature change of the elastic modulus is also large. Such a change in physical properties of the material itself causes a change in the braking force. Therefore, it is a problem to incorporate a mechanism for accurately monitoring and feeding back the braking force.

  An object of the present invention is to solve the above-described problems and to provide a small and light electric brake device and an auxiliary device that can accurately adjust a braking force.

  In order to achieve the above object, in the present invention, an electric brake device for braking the movement of a moving body, which is deformed by a brake pad pressed against the moving body and an electric signal for pressing the brake pad. An electric actuator including a material, a pressure sensor for monitoring the braking force by the actuator, a controller for determining the braking force by reading an output from the pressure sensor, and a power source for controlling an electric signal output by the controller An electric brake device is provided.

  In order to achieve the above object, in the present invention, an auxiliary device for assisting a pedestrian, a belt hoisting device for winding up a walking assist belt, a brake pad pressed against the belt, An electric brake device including an electric actuator including a material that is deformed by an electric signal for pressing the brake pad, a sensor for monitoring a brake force by the electric actuator, and a control box for controlling the electric brake device The control box determines the braking force based on the signal related to the belt withdrawal amount from the belt hoisting device and the output signal from the sensor, and generates an electric signal to be applied to the electric actuator so as to generate the determined braking force. Provide an auxiliary device to control.

  Furthermore, in order to achieve the above object, according to the present invention, there is provided an auxiliary device for assisting a pedestrian, which is pressed against a fixed disk, a rotating disk rotatable with respect to the fixed disk, and the rotating disk. An electric brake device including a brake pad, an electric actuator including a material that is deformed by an electric signal for pressing the brake pad, a sensor for monitoring a braking force by the electric actuator, and the electric brake device are controlled. The control box includes a control box, and the control box determines a braking force based on a signal related to the rotation angle of the rotating disk from the electric brake device and an output signal from the sensor, and generates the determined braking force. An auxiliary device that controls the electrical signal applied to the To.

  ADVANTAGE OF THE INVENTION According to this invention, the small and lightweight brake device which can control brake force correctly electrically is implement | achieved, and it becomes applicable to a wearable assist apparatus for the purpose of assisting human movement and posture maintenance.

It is a figure which shows the principle of operation of the dielectric elastomer actuator used by this invention. It is a figure which shows the basic cross-section of the electric brake device of this invention. It is sectional drawing for demonstrating the force by a dielectric elastomer actuator used by this invention. It is the figure which showed the mode of the actuation at the time of fixing the electrode of both surfaces of the dielectric elastomer actuator shown in FIG. It is the figure which showed the mode of actuation when lubricating oil was applied without fixing the electrode of both surfaces of the dielectric elastomer actuator shown in FIG. It is a graph which showed the reciprocal number of the resistance value of a pressure sensor with respect to the pressure applied to the film-form pressure sensor which is a sensor used by this invention. It is the graph which showed how the value of force obtained from a film-like pressure sensor which is a sensor used by the present invention changes when an object slips on the sensor surface. It is a figure which shows schematic structure of the brake device based on a 1st Example. It is a figure which shows another cross-section of the brake device based on a 1st Example. It is a conceptual diagram which shows the walking assistance apparatus based on a 2nd Example. It is a block diagram which shows the function structure of the walking assistance apparatus based on 2nd Example. It is a flowchart figure which shows operation | movement of the walk assistance apparatus based on 2nd Example. It is the conceptual diagram which looked at the external shape of the disc brake device based on the 3rd Example from diagonally upward. FIG. 6 is an exploded view of a disc brake device according to a third embodiment. FIG. 14 is a cross-sectional view taken along the line B-B ′ of the disc brake device shown in FIG. 13 according to a third embodiment. FIG. 14 is a conceptual diagram showing a knee-mounted walking assist device using the disc brake device shown in FIG. 13 according to a fourth embodiment. It is sectional drawing of the disk brake apparatus for walking assistance apparatuses of a knee mounting type incorporating the encoder which detects a rotation angle based on a 4th Example.

  Prior to describing the embodiments of the present invention with reference to the drawings, the principle of the present invention will be described below.

  The internal basic structure of the electric brake device of the present invention includes a brake pad that is a friction material pressed against the moving body to brake the movement of the moving body, an actuator made of an electroactive polymer for pressing the brake pad, and a brake It consists of a pressure sensor for monitoring force. Further, outside the apparatus, there is a controller that reads an output from the pressure sensor to determine an optimum braking force, and an actuator power source whose output is controlled by the controller.

  As the electroactive polymer constituting the actuator for pressing the brake pad, a conductive polymer, an ion conductive polymer, a gel, a dielectric elastomer, or the like is used. In particular, an actuator using a dielectric elastomer is known to have a high response speed, deformation amount, generated stress, and energy conversion efficiency. Therefore, the dielectric elastomer actuator will be described here.

  FIG. 1 shows the principle of an actuator used in the present invention. (A) in the figure shows a state in which no voltage is applied to the electrodes on both sides of the dielectric elastomer actuator, and (B) in the figure shows a state in which a voltage is applied to the electrodes on both sides of the dielectric elastomer actuator, It is a conceptual diagram which shows the state which shrunk and the electrode area expanded. As shown in FIG. 1A, the dielectric elastomer actuator 1 has a structure in which flexible electrodes 3 and 4 are provided on both surfaces of an elastomer material 2. As shown in FIG. 1B, when a voltage is applied between the electrodes, the electrodes are attracted by the Coulomb force, so that the distance between the electrodes is reduced and the entire shape is changed so as to spread in the electrode surface.

  With reference to FIG. 2, an operation method when the above-described actuator is used as a brake will be described. FIG. 2 is a sectional view of the basic structure of the brake device of the present invention. The dielectric elastomer actuator 1, the brake pad 6, and the moving body 9 are disposed between the substrates 25 and 26. The substrates 25 and 26 are spatially fixed. The dielectric elastomer actuator 1 is fixed to the substrate 25, and the brake pad 6 is fixed to the dielectric elastomer actuator 1. It is assumed that the moving body 9 can move along the surface of the substrate 26 different from the substrate on which the dielectric elastomer actuator 1 is fixed.

  In FIG. 2A, the dielectric elastomer actuator 1 extends in the inter-electrode direction, thereby pressing the brake pad 6 against the moving body 9. A vertical drag N is applied to the moving body 9 by the dielectric elastomer actuator 1, whereby a frictional force F is generated between the brake pad 6 and the moving body 9. The movement of the moving body 9 is braked by this frictional force F (braking state).

  In FIG. 2B, when the dielectric elastomer actuator 1 contracts in the direction between the electrodes, the brake pad moves away from the moving body, and the moving body 9 can move freely (non-braking state).

  Next, the magnitude of the braking force of the brake using the dielectric elastomer actuator will be described with reference to FIG. FIG. 3 is a cross-sectional view of the dielectric elastomer actuator 1. FIG. 3A shows a state in which the voltage V1 is applied to the electrodes 3 and 4 on both surfaces of the dielectric elastomer actuator 1 and no mechanical load is applied to the actuator. The distance between the electrodes at this time is z1. FIG. 3B shows a state in which a mechanical load is applied from the upper surface to the state of FIG. The elastomer which is an elastic body is pushed in by the load, and the distance between the electrodes is reduced by Δz. At this time, the force generated by the elastomer is approximately proportional to the amount of shrinkage, and is balanced with the applied load.

When the force generated by the elastomer is f, the electrode area is S, and the elastic modulus of the elastomer is Y, the following equation (1) is obtained.
f = (Δz / z1) · Y · S (1)
When used as a brake, this force f is applied as a vertical drag to the moving body 9 via the brake pad 6, so that the frictional force F, that is, the braking force, is defined by the friction coefficient at the interface between the brake pad 6 and the moving body 9 as μ. Approximately, it can be expressed as the following equation (2).
F = μf = (Δz / z1) · μ · Y · S (2)
Since z1 in the formula (2) can be adjusted by the voltage applied to the dielectric elastomer actuator, the braking force can be adjusted.

  Here, since the elastomer material is an incompressible material, the volume is constant with respect to deformation. Therefore, when an attempt is made to obtain deformation in the inter-electrode direction, the deformation in the inter-electrode direction is also suppressed if the electrode surface is fixed and the deformation in the electrode surface is inhibited.

  FIG. 4 is a schematic view showing a cross section of the dielectric elastomer actuator in such a situation. (A) of the figure shows a state where no voltage is applied to the electrodes on both sides of the dielectric elastomer actuator, and (B) of the figure shows a concept of a cross section showing a state where a voltage is applied to the electrodes on both sides of the dielectric elastomer actuator. FIG. 4A is a diagram in the case where the upper and lower sides of the dielectric elastomer actuator 1 are fixed to the substrate 5 and the brake pad 6. FIG. When a voltage is applied to this, the distance between the electrodes is somewhat reduced by swelling like a via barrel as shown in FIG. 4B, but compared to the case where it freely spreads in the plane of the electrodes 3 and 4, The deformation rate becomes small. In that case, a high voltage must be applied to the dielectric elastomer actuator in order to obtain sufficient deformation.

  Therefore, as shown in FIG. 5, the upper and lower sides of the actuator are not fixed to the entire surface of the substrate or the brake pad, but are fixed by the fixing portion 7 having a partial area sufficiently smaller than the electrode area. (A) of the figure shows a state in which no voltage is applied to the electrodes on both sides of the dielectric elastomer actuator, and (B) in the figure shows a cross-sectional view in a state in which a voltage is applied to the electrodes on both sides of the dielectric elastomer actuator. . The interface between the actuator other than the fixed portion and the substrate or the brake pad is set in a slippery state so that the actuator can easily expand and contract. For example, it can be realized by applying lubricating oil to the interface or by using a slippery material such as Teflon (registered trademark) on the surface of the substrate or brake pad that contacts the actuator.

  FIG. 5 shows the case where the lubricating oil 8 is applied. In this case, the actuator can be sufficiently deformed in the surfaces of the electrodes 3 and 4 by sliding on the surface of the substrate or the brake pad, and as a result, can be greatly deformed in the direction between the electrodes. In this way, the actuator can be deformed and the brake pad can be moved without applying a large voltage. If the moving distance is small, the brake pad remains rubbed against the moving body during non-braking, which is not preferable. Since some dielectric elastomer actuators have a deformation rate of 70%, the distance traveled can be made sufficiently large when incorporated in a brake.

  In addition, it is known that the volume and elastic modulus of an elastomer material change with temperature. In the case of a brake that brakes with a frictional force, it is conceivable that the temperature of the brake pad easily rises due to frictional heat, and the temperature of the actuator that presses the brake pad changes. As shown in the equation (2), since the braking force depends on the distance between the electrodes of the dielectric elastomer actuator and the elastic modulus of the elastomer, the distance between the electrodes changes due to a change in the volume of the elastomer due to a temperature change. If the elastic modulus of the elastomer changes, a desired braking force may not be obtained. By monitoring the temperature, the characteristics of the material can be evaluated and the required applied voltage can be determined, but the thermal conductivity of the elastomer itself is low and it is difficult to accurately estimate the temperature.

  Therefore, this force may be monitored with a pressure sensor or the like by utilizing the fact that the braking force, that is, the frictional force is proportional to the vertical drag on the friction surface. In this case, it is appropriate to arrange the sensor at a location thermally away from the friction surface of the brake pad so that the frictional heat does not affect the pressure sensor. Since the elastomer has low thermal conductivity, the influence of heat on the pressure sensor can be minimized by arranging the pressure sensor on the surface opposite to the brake pad. Therefore, it is appropriate to install between the dielectric elastomer actuator 1 and the substrate 5 of FIG. If the sensor is fixed to the deforming actuator, the deformation of this portion is hindered. Therefore, it is appropriate to fix the pressure sensor on the surface of the substrate 5 with respect to the dielectric elastomer actuator 1.

  Although there are various types of pressure sensors, the film-like pressure sensitive sensor is light and small in size, and is suitable for the purpose of being incorporated in a lightweight brake device. Such sensors include Nitta Flexiforce and Interlink FSR (Force Sensing Resistor). Since these sensors are as thin as several hundred microns, even if they are incorporated in a brake device, their thickness is not affected. These sensors have a mechanism in which the resistance of the sensor changes depending on the pressure applied to the sensor surface.

  FIG. 6 shows the reciprocal of the resistance value of the pressure sensor with respect to the pressure applied to the film pressure sensor. Therefore, the pressure can be estimated by measuring the sensor resistance value. However, in the case of this film-like pressure sensor, when an object slides on the sensor surface and a horizontal force (shearing force) is present on the sensor surface, a correct force may not be detected. The relationship of the reciprocal of the resistance value of the pressure sensor with respect to the pressure applied to the film-like pressure sensor shown in FIG. 6 is a state in which the sensor and an object that touches the surface and exerts a force on the sensor do not slide on each other (stationary State). Accordingly, when an object is sliding on the sensor surface (sliding state), an incorrect value may be obtained if the pressure is estimated from the sensor resistance value based on this graph.

  Actually, as shown in the graph of FIG. 7, the force value estimated from the film-like pressure sensor fluctuated greatly in the sliding state. The vertical axis in FIG. 7 is the ratio of the magnitude of the force estimated from the pressure sensor to the magnitude of the actual applied force, and the horizontal axis is time. The magnitude of the force estimated from the pressure-sensitive sensor is obtained from the relationship between the sensor resistance value in a stationary state and the pressure applied to the sensor in FIG. From the start of measurement until 1 second, it is stationary, and the actual force and the force estimated from the pressure-sensitive sensor coincide. From 1 second to 3 seconds was in a slipping state, and at this time, the magnitude of the force estimated from the pressure sensor deviated greatly from the magnitude of the actually applied force. In the sliding state, the vehicle slides at a relative speed of 5 millimeters per second.

  In the lightweight brake device, when the structure shown in FIG. 5 is used so that the actuator is sufficiently deformed, the actuator slides on the substrate except for the fixing portion 7. Therefore, when the pressure sensor is installed on the dielectric elastomer actuator 1 side of the substrate 5, it is in a sliding state except for the fixed portion 7. For this reason, the pressure sensor cannot measure an accurate force. On the other hand, since the fixed portion 7 is in a stationary state, if the pressure sensor is arranged at this position, an accurate normal force can be detected, and as a result, the braking force can be accurately measured.

  In this way, in the basic structure of the brake device of the present invention, an accurate braking force can be measured, and by using this value, the controller for control determines the voltage required for the actuator and controls the actuator power supply. A desired braking force can be obtained.

  An embodiment of the basic structure of the brake device will be described as a first embodiment with reference to FIG. FIG. 8 is a conceptual diagram showing a configuration of a brake device that brakes a belt-like moving body that moves linearly. FIG. 8A is a conceptual view of the outer shape of the brake device of this embodiment viewed obliquely from above, and FIG. 8B is a cross-sectional view taken along the line AA ′ of the brake device of FIG. 8C is a cross-sectional view taken along line AA ′ of the brake device of FIG. 8A in the non-braking state.

  As shown in FIG. 8 (A), the brake device 10 includes a case 11 with a lid 15 in which the components are contained, and the belt passes through two openings 12 and 13 opened on the left and right sides of the case. The shaped moving body 14 penetrates. A power cable 16 for applying a voltage to the dielectric elastomer actuator and a signal cable 17 for outputting a pressure sensor measurement value are provided from the side surface of the case 11, and are connected to an external actuator power source and controller (not shown). It is connected.

  As shown in the sectional view of FIG. 8B, the brake pad 18, the dielectric elastomer actuator 1, and the pressure sensor 19 are disposed inside the case 11. The pressure sensor 19 is embedded and fixed in the bottom portion inside the case 11 at the position of the fixing portion 7 so that the surface thereof coincides with the bottom surface. If the convex portion is formed without embedding the pressure sensor 19, the convex portion shows a higher pressure than the others, so that an accurate pressure cannot be measured. When the unevenness cannot be eliminated, it is necessary to measure and calibrate the pressure measurement error due to the convex portion in advance.

  The dielectric elastomer actuator 1 is arranged so that the electrode surfaces of the flexible electrodes 3 and 4 arranged on both sides of the actuator are parallel to the bottom of the case 11. The dielectric elastomer actuator 1 is fixed to the case 11 via the pressure sensor 19 at a fixing portion 7 that contacts the pressure sensor 19 fixed to the case 11. On the brake pad side of the fixing portion 7 across the dielectric elastomer actuator 1, there is a fixing portion 20 for fixing the brake pad 18 and the dielectric elastomer actuator 1.

  If the area of the fixing parts 7 and 20 is large, the operation of the actuator 1 is affected. However, if the area of the fixed portion 7 is smaller than the area of the pressure sensor 19, the actuator is sliding on a part of the surface of the pressure sensor, which affects the pressure measurement. Therefore, it is desirable that the fixed portion 7 has a larger area than the pressure sensor 19. The lower limit of the area of the fixing portion 7 depends on the adhesive force of the adhesive to be fixed, in addition to the size of the pressure sensor, but can be fixed with a general adhesive if it is about 2% of the area of the actuator 1. As long as the pressure sensor is not disposed at the lower portion of the fixed portion 20, it may be about 2% of the area of the actuator 1.

  As described above, the lubricant 8 is applied between the actuator 1 and the bottom surface of the case 11 and between the actuator 1 and the brake pad 18. Above the brake pad 18, the belt-like moving body 14 is passed from the outside of the case 11 through the openings of the case 11, 12 and 13. The belt-like moving body 14 can move in the A-A ′ direction through the openings 12 and 13. A case lid 15 is disposed on the belt-like moving body 14, and the lid 15 is fixed to the case 11.

  In the A-A ′ direction in FIG. 8A, the brake pad 18 is in contact with the inside of the case 11 via the linear bearing 21. As a result, the brake pad 18 moves up and down in the case 11 without resistance, and at the same time, when the belt-like moving body 14 moves in the direction of AA ′, the brake pad 18 is attached to the belt moving body 14. It has a structure that suppresses movement in the same direction as the movement direction.

  The operation of the brake device will be described with reference to FIGS. 8B and 8C. When no voltage is applied to the dielectric elastomer actuator or the applied voltage is small, the brake pad 18 is pushed up as shown in FIG. Since the belt-like moving body 14 is sandwiched between the pushed-up brake pad 18 and the case lid 15, the moving speed thereof is reduced. If the pressing force of the actuator 1 is strong, the belt-like moving body 14 is fixed to the case 11.

  As the voltage applied to the dielectric elastomer actuator 1 is increased, the thickness of the dielectric elastomer actuator 1 decreases, so that the brake pad 18 comes to a lowered position. As shown in FIG. 8C, when the dielectric elastomer actuator 1 is sufficiently contracted, the brake pad 18 is separated from the belt-like moving body 14, and the belt-like moving body 14 can move without resistance. By adjusting the voltage applied to the actuator 1, the frictional force between the brake pad 18 and the belt-like moving body 14 can be adjusted, so that the degree of deceleration of the belt-like moving body can be adjusted.

  When the brake device having such a structure of the present embodiment is manufactured using a dielectric elastomer actuator having a length of 50 mm, a width of 25 mm, and a thickness of 10 mm, a maximum 30 Newton force is generated as a brake force. I was able to. At this time, by applying a voltage of 100 V to the dielectric elastomer actuator 1, the brake device 10 was brought into a non-braking state, and the belt-like moving body 14 could be moved. Here, the length in the moving direction of the belt-shaped moving body 14, that is, the AA ′ direction in FIG. 8A, and the width in the direction perpendicular to the AA ′ direction in the plane of the flexible electrodes 3 and 4. Have taken. The brake device 10 manufactured using this actuator 1 weighs about 150 grams except for the belt-like moving body 14, and a lightweight brake device 10 is realized.

  When a voltage of 70 V was applied, the braking force was 15 Newton, and the vertical drag detected by the pressure sensor 19 was 31 Newton. When the temperature is raised by 50 degrees in this state, the elastomer constituting the actuator 1 is thermally expanded and the elastic modulus is lowered. As a result, the vertical drag is reduced and the braking force is also lowered. When the braking force was measured without performing control using the signal from the pressure sensor 19, the braking force was reduced to 9 Newton. Therefore, when control using the signal from the pressure sensor 19 is performed, an external controller (not shown) immediately controls the voltage to the dielectric elastomer actuator 1, and a braking force of 15 Newtons is obtained by applying a voltage of 60V. I was able to get it. An example of this external controller will be exemplified in the second embodiment.

  In the embodiment of FIG. 8, the flexible electrodes 3 and 4 are displayed as being exposed on the surface of the dielectric elastomer actuator 1, but in the exposed state, the voltage applied to the actuator 1 is applied to the case 11 and the brake pad 18. It also depends on. Therefore, it is desirable to cover the surface of the electrode surface of the actuator 1 with a flexible insulator. In view of not hindering the operation of the actuator, it is desirable that the actuator 1 is covered with an elastomer constituting the actuator 1 or a material having a smaller elastic coefficient. In addition to covering the actuator surface in this way, it is desirable to cover the inside of the case and the actuator side of the brake pad 18 with an insulating film. Further, in FIG. 8, the lubricating oil is applied to improve the slip of the interface between the dielectric elastomer actuator 1 and the bottom of the case 11 and the brake pad 18, but the bottom surface of the case 11 or the actuator side of the brake pad 18 is on the actuator side. The slip of the interface may be improved by making the surface slippery like Teflon.

  8 shows the brake device 10 in which the dielectric elastomer actuator 1 is arranged only on one side with respect to the belt-like moving body 18, the brake pad 18 and the actuator 1 are connected as shown in FIG. It may also be arranged on the opposite side so that the belt-like moving body 14 is sandwiched from both sides. If the operation of the upper and lower actuators 1 is accurately performed with such a structure, the position of the belt-like moving body 14 in the vertical direction does not shift. In addition, since the portion where the belt-like moving body 14 contacts the case lid can be reduced as compared with the case where the actuator 1 is arranged only on one side, the belt-like moving body 14 and the case 11 lid between the case 11 and the non-braking state can be reduced. Friction can be reduced.

  In the brake device 10 of the first embodiment described above, the actuator power supply and the controller are arranged outside the case 11, but can be arranged in the case 11 using an on-board power supply or a microcomputer. According to the present embodiment, a lightweight and compact brake device can be provided.

In Example 2, an example of a walking assistance device using the lightweight brake device shown in Example 1 will be described.
When descending the stairs, use the quadriceps or greater gluteal muscles to keep your knees and hips bent. If these muscles weaken, this posture cannot be maintained, and the deceleration when landing the opposite foot cannot be performed sufficiently. In that case, since the landing foot collides with the ground without decelerating, a shock is applied to a joint such as a knee. This is accompanied by an uncomfortable feeling that hurts the joint or feels pain. This walking aid works to compensate for such muscle weakness.

  10A and 10B are schematic views of the walking assist device 100 using the lightweight brake device 10 shown in the first embodiment. (A) of the figure is a conceptual diagram of the lower body of a person wearing the electric walking assist device as viewed from the left front, and (B) of the same figure is the lower body of the person wearing the electric walking assist device as viewed from the left rear. It is a conceptual diagram.

  The walking assist device 100 includes a set of a lightweight brake device 10, a belt hoisting device 101, a control box 102 for controlling the walking assist device, a waist belt 103, a belt 104 connecting from the waist to the knees, and a knee for each foot. It consists of a fixed lower knee belt 105.

  A control box 102, a lightweight brake device 10, and a belt hoisting device 101 are fixed to the waist belt 103. The lightweight brake device 10 is disposed between the belt hoisting device 101 and the below-knee belt 105, and the belt 104 penetrates the inside of the device. The belt 104 connected from the lower back to the lower knee passes from the belt hoisting device 101, passes through the lightweight brake device 10 and the buttocks of the wearer, passes through the front of the knee, and is fixed to the lower knee belt 105. The belt hoisting device 101 includes an encoder for outputting a signal for detecting the pull-out amount of the belt 104 and the belt speed in a predetermined cycle. The signal for detecting the pull-out amount and speed can be output from the encoder by managing the amount of belt remaining in the belt hoisting device 101.

  Further, since the belt hoisting device 101 has a spring inside, and the belt 104 is always pulled up with a tension that does not loosen, the extra length of the belt 104 becomes longer when the wearer stands upright. As a result, the belt is wound and stored in the belt winding device 101. When the wearer bends the knee joint or the hip joint, such as when going down the stairs, the necessary amount of the belt 104 is pulled out from the belt hoisting device 101 by the movement of the wearer.

  FIG. 11 is a block diagram illustrating an example of a functional configuration of the walking assist device 100 centering on the control box 102 of the present embodiment. A signal output at a predetermined sampling period from the encoder 110 of the belt winding device 101 is converted into a belt drawing amount by a belt drawing amount conversion unit 111 in the control box 102. The value of the pull-out amount is sent to the belt pull-out speed calculation unit 112 and the brake force calculation unit 113. The belt withdrawal speed calculation unit 112 calculates the belt withdrawal speed using the withdrawal amount and preset sampling cycle information, and sends the belt withdrawal speed to the brake force calculation unit 113. As will be described later, the brake force calculation unit 113 calculates the knee angle and the knee angular velocity by using the belt withdrawal amount and the withdrawal speed and referring to the normal walking data of the wearer stored in the memory 115. Based on these data, the state of walking is judged and the braking force is determined.

  Based on the determined braking force, a voltage to be applied to the dielectric elastomer actuator 1 in the brake device 10 is determined, and a control signal is sent to the small power source 116. The actual brake force is measured by the pressure sensor 19 in the brake device 10, and the sensor signal is converted into the brake force by the brake force converter 114 and sent to the brake force calculator 113. Based on this value, the brake force calculation unit 113 adjusts the voltage applied to the actuator 1 from the small power source 116 so that the previously determined braking force is obtained.

  The control box 102, except for the small power supply 116, has a central processing unit (CPU) that constitutes a normal processing unit, a memory that constitutes a storage unit that stores programs and the like, and a computer configuration having an interface unit. By executing various programs, the above-described belt withdrawal amount conversion unit 111, belt withdrawal speed calculation unit 112, brake force calculation unit 113, and brake force conversion unit 114 can be realized. Therefore, the belt withdrawal amount conversion unit 111, the belt withdrawal speed calculation unit 112, the brake force calculation unit 113, and the brake force conversion unit 114 in the control box 102 can be collectively referred to as a processing unit or a controller. Further, the small power source 116 may be installed not on the control box 102 but on the brake device 10 side.

  FIG. 12 is a flowchart for explaining a procedure of brake force control for walking assistance when the stairs are lowered by the walking assistance device 100 of the present embodiment. The brake force calculation unit 113 calculates the knee angle and the knee angular velocity using the input belt pull-out amount and pull-out speed (S100). The knee angular velocity can be obtained by differentiating the knee angle. Since the relationship between the knee angle and the belt withdrawal amount varies depending on the wearer, data stored in the memory 115 in advance is referred to.

  Then, the obtained knee angle and knee angular velocity are compared with the data stored in the memory 115 (S101), and it is determined whether or not the stairs are descending (S102). If it is not descending, walking assistance is not performed. If the knee is descending, it is determined whether the knee angle is smaller than the set threshold value, that is, the knee is bent deeply and whether the knee angular velocity threshold value for the knee angle is exceeded (S103).

  Although illustration is omitted, the memory 115 stores temporal change data of the left and right knee angles and knee angular velocities for one cycle when the wearer normally moves up and down. Normally, when going up the stairs, it takes time to stretch the knee, and it takes a short time to bend the knee, while when going down, the opposite is true, and the time taken to stretch the knee is bent. Is shorter than the time it takes. Therefore, if the direction in which the knee extends is the direction in which the knee angle increases, speaking of the knee angular velocity, when going up the stairs, the time for taking a positive value is longer than the time for taking a negative value in one cycle of walking. Become. Based on this fact, it can be determined whether the stairs are up or down (S102).

  When either condition is not satisfied, walking assistance is not performed, so a new knee angle and knee angular velocity are calculated and acquired again (S100). If step S103 is satisfied, the braking force is calculated based on the knee angle and knee angular velocity so that the vehicle can decelerate before landing (S104). The upper limit of the braking force is set in advance so that the belt does not suddenly decelerate due to an excessively large braking force and a strong force is not applied to the wearer. In step S105, it is determined whether the calculated braking force is equal to or lower than the upper limit. If the calculated braking force is equal to or higher than the upper limit, the braking force is set to the upper limit (S106).

  If the braking force is below the upper limit, the calculated value is set as it is as the braking force (S106). From the brake force value set in step S106, the voltage applied to the actuator of the brake device 10 is determined and output (S107). The brake operates accordingly. The brake force at this time is acquired by the pressure sensor 19 (S108), compared with the value set in step S106 (S109), and if different, the brake force is adjusted by repeating steps S107 to S109. In this way, the necessary braking force is applied to the belt 104, assisting the deceleration of the knee angle, and mitigating the impact of the wearer on landing.

  In the walking assist device of the present embodiment described above, since the force of the wearer is used to move the foot, a motor (actuator) with an output higher than necessary is not required, and thus it is safe even when worn. . Moreover, since the brake device using the dielectric elastomer actuator used as a brake is lightweight, there is little burden even if it is equipped. In addition, since a passive assisting device such as a supporter is always under tension, an excessive force is applied when the joint is bent, which places a burden on the wearer. By mounting such an electric brake, tension is applied when necessary, so that it is possible to avoid a burden on the wearer when the auxiliary force is unnecessary.

In the third embodiment, a description will be given of an embodiment of a disc brake device that brakes a moving body that rotates.
In the first embodiment, a brake device that brakes a moving body that moves linearly has been described. In the third embodiment, a disk that brakes a rotating moving body that operates as a brake pad that is a friction material. The present invention relates to a brake device.

  FIG. 13 is a conceptual diagram showing a brake portion of the disc brake device 30 of the present embodiment. The brake portion of the disc brake device includes an arm 31 and two discs 32 connected thereto, another arm 33 and a disc 34 connected thereto, two brake portions 35 disposed between them, a disc, It consists of a rotating shaft 36 that penetrates and fixes the brake. Two disks 32 connected to the arm 31 are fixed to a rotating shaft 36. On the other hand, the disk 34 connected to the arm 33 is a moving body that rotates, and can rotate about a rotation shaft 36. Therefore, the disk 32 may be called a fixed disk and the disk 34 may be called a rotating disk.

  Two brake parts 35 are arranged on both surfaces of the rotating disk 34 and between the fixed disk 32. Since the brake unit 35 is fixed to the fixed disk 32, it works so that the disk 34 does not rotate with respect to the fixed disk 32. The brake unit 35 is electrically connected to a power source and a controller (both not shown).

  The detailed structure of the disc brake device 30 of the present embodiment will be described with reference to FIG. 14 is an exploded perspective view of the disc brake device 30 shown in FIG. The disk brake device 30 includes a rotating disk 34 having two fixed disks 32 connected to an arm 31, two dielectric elastomer actuators 38, two brake pads 39, two cases 37, and an arm 33. As shown in FIG. 14, the configuration is symmetrical.

  Each of the disks 32 and 34, the dielectric elastomer actuator 38, and the brake pad 39 has a disk-like outer shape, and has a circular through hole at the center thereof so that the rotary shaft 36 can pass therethrough. The rotating shaft 36 is fixed to the two fixed disks 32. The two cases 37 are cylindrical and are fixed to the fixed disk 32, respectively. On the other hand, the rotating disk 34 has a bearing 40 in the central through hole thereof, and is coupled to the rotating shaft 36 through the bearing 40. Therefore, the rotating disk 34 rotates around the rotating shaft 36 with low friction.

  The through hole of the dielectric elastomer actuator 38 is set larger than the rotation shaft 36 so that the dielectric elastomer actuator 38 does not touch the rotation shaft 36. On both surfaces of the dielectric elastomer actuator 38, there are fixing portions 41 at positions along the central through hole. The dielectric elastomer actuator 38 is fixed to the fixed disk 32 via one fixing portion 41. A pressure sensor 45 is embedded on the surface of the fixed disk 32 with respect to the dielectric elastomer actuator 38 at a portion fixed to the dielectric elastomer actuator 38 so that the surface thereof coincides with the surface of the fixed disk 32. In FIG. 14, two pressure sensors 45 are shown for each disk, but one may be used. The output of the pressure sensor 45 is output to the control box using a wire passing through a rotation shaft (not shown).

  From the dielectric elastomer actuator 38, a power cable is connected to be electrically connected to an external power source (not shown). Further, a cable for electrical connection with an external controller (not shown) is provided from the pressure sensor 45. By monitoring the pressure at the portion where the dielectric elastomer actuator 38 is fixed, an accurate pressure can be detected regardless of the movement of the actuator. The controller determines the necessary braking force from this pressure value, and adjusts the voltage applied to the dielectric elastomer actuator 38 so as to obtain the necessary braking force.

  The dielectric elastomer actuator 38 is fixed to the brake pad 39 through a fixing portion 41 installed on the surface opposite to the surface of the dielectric elastomer actuator 38 with respect to the fixed disk 32. As in the first embodiment, a lubricant is applied between the dielectric elastomer actuator 38 and the fixed disk 32 or the brake pad 39, and the dielectric elastomer actuator can expand and contract with low friction.

  A cylindrical linear bearing 42 is fixed in the central through hole of the brake pad 39 so that the rotary shaft 36 can move with low friction on the inner diameter of the linear bearing. The brake pad 39 has two scratch marks 43 for preventing rotation. Here, an example in which there are two locations is shown, but the number of scratches may be at least one. The case 37 has a cylindrical outer shape and is fixed to the fixed disk 32 so as to cover the dielectric elastomer actuator 38 and the brake pad 39.

  The case 37 has at least one claw 44 inside thereof. The claw 44 is adapted to be fitted to the notch 43 of the brake pad 39. Therefore, the brake pad 39 is prevented from rotating in the same direction as the rotation direction of the rotary disk 34 during braking. When the brake pad 39 tries to rotate, the dielectric elastomer actuator 38 is distorted, the fixing portion 41 is broken or the dielectric elastomer actuator 38 itself is broken, and the life of the brake device is shortened. Therefore, the life of the brake device can be extended by suppressing the rotation of the brake pad.

  The thickness of the claw 44 in the direction of the rotation axis is set to be sufficiently smaller than the depth of the scraper 43 in the direction of the rotation axis so that the brake pad can sufficiently move in the direction of the rotation axis during braking. Lubricating oil is applied to the interface between the scraper 43 and the claw 44 so as not to hinder the movement of the brake pad in the direction of the rotation axis during braking.

  Here, in order to suppress the rotation of the brake pad, the shape of the claw 44 and the scraper 43 is selected. However, the linear bearing 42 fixed to the brake pad 39 does not rotate with respect to the rotation shaft 36. Can also be realized. If it does in this way, the shape of a case or a brake pad can be simplified. It can also be realized by separately providing a bearing similar to the linear bearing 42 and a slide shaft. If a bearing is used, the friction at the time of movement of a brake pad can be reduced more.

  FIG. 15 is a sectional view taken along the line B-B ′ of the disc brake device 30 of FIG. 13. FIG. 15A shows a braking state in which no voltage is applied to the disc brake device and the actuator pushes up the brake pad. FIG. 15B shows a state in which voltage is applied to the disc brake device. In a non-braking state.

  The disc brake device 30 includes two fixed discs 32, a rotary disc 34, a case 37 that covers a brake portion, a dielectric elastomer actuator 38, a brake pad 39, and a rotary shaft 36 that passes through the center thereof. The structure is symmetrical with respect to the rotating disk 34 as shown in FIG.

  The two fixed disks 32 are fixed to the rotary shaft 36. The case 37 is fixed to the fixed disk 32. The dielectric elastomer actuator 38 is fixed to the fixed disk 32 and the brake pad 39 via a fixing portion 41. A pressure sensor 45 is embedded at a position of the fixed portion 41 of the fixed disk 32.

  As shown in FIG. 15A, when the left and right brake pads 39 are pushed in the direction of the rotating disk 34 by the two dielectric elastomer actuators 38 arranged on the left and right of the rotating disk 34, the rotating disk 34 is sandwiched. The rotation of the disk 34 with respect to the fixed disk 32 is suppressed.

  When a voltage is applied to the two dielectric elastomer actuators 38, the thickness of the dielectric elastomer actuator 38 is reduced, so that the force for pressing the brake pad 39 is weakened. If a sufficient voltage is applied, the brake is applied as shown in FIG. The pad 39 and the rotating disk 34 are not in contact with each other. In this case, the rotating disk 34 can rotate around the rotating shaft 36 with low friction. Since there is a bearing 40 between the rotary disk 34 and the rotary shaft 36, the rotation is not hindered in the state of FIG. 15B which is a non-braking state.

  Here, it is displayed that the flexible electrode is exposed on the surface of the dielectric elastomer actuator, but it is desirable to cover the electrode surface of the actuator with a flexible insulator. As a result, the voltage applied to the actuator is not applied to the case or the brake pad, which is safe. It is desirable that the actuator is covered with an elastomer constituting the actuator or a material having a smaller elastic modulus in that the actuator operation is not hindered. In addition to covering the actuator surface in this way, it is desirable to cover the inside of the case and the actuator side of the brake pad with an insulating film. In this embodiment, the lubricating oil is applied to improve the slip of the interface between the dielectric elastomer actuator and the case bottom and the brake pad. However, the surface of the case bottom or the actuator side of the brake pad is not like Teflon. It may be made of slippery material.

  In the present embodiment, the dielectric elastomer actuator 38 is composed of a pair of electrodes. However, instead of this, a multilayered dielectric elastomer actuator may be used. In the case of actuators with multiple layers as described above, the advantage is that the voltage to be applied can be reduced because the layers of each actuator are thin, that is, the distance between the electrodes is small, when the size is the same as a whole. is there.

  Thus, in the disc brake device of this embodiment, the voltage applied to the dielectric elastomer actuator 38 is adjusted based on the rotation angle of the rotary disc and the value monitored by the pressure sensor, so that the rotary disc 34 is fixed. Necessary braking can be applied to the rotation with respect to the disk 32.

In the fourth embodiment, an embodiment of a knee-mounted walking assist device using the lightweight brake device shown in the third embodiment will be described.
As in Example 2, this walking assistance device is designed to prevent the landing of the foot from being sufficiently slowed down due to the weakening of the leg muscles when the stairs are lowered, and to prevent the knees and other joints from being shocked. work.

FIG. 16 is a schematic view of a walking assist device 200 that is mounted on a knee joint, using the lightweight disc brake device 30 shown in the third embodiment.
The walking assist device 200 includes a lightweight disc brake device 30, a control box 202 that controls the walking assist device, a thigh belt 203 fixed to the thigh, and a lower knee belt 205 fixed to the lower knee. Sockets 206 are installed on the thigh belt 203 and the below-knee belt 205, respectively, so that the arms 31 and 33 extending from the lightweight disc brake can be fixed. Thereby, the arms 31 and 33 extending from the disc brake device 30 can follow the movements of the thigh and the lower knee, respectively.

  Although illustration of the block diagram which shows a function structure in the walking assistance apparatus of a present Example is abbreviate | omitted, it cannot be overemphasized that it can comprise similarly to the block diagram of FIG. The changes are that the encoder corresponding to the encoder 110 provided in the belt hoisting device 101 is provided in the disc brake device 30, and the belt drawing amount conversion unit 111 in the control box 102 and the belt drawing speed calculation. The section 112 is changed to a rotation angle conversion section for the knee joint and a rotation angular velocity calculation section for the knee joint, and the data in the memory 115 is changed to data relating to the wearer's knee joint.

  As shown in FIG. 17, a hollow shaft-shaped encoder 46 is fixed inside the disc brake device 30 and inside the rotating disc 34. The rotating shaft 36 of the disc brake device 30 is fitted so as to coincide with the rotating shaft of the encoder 46. Since the rotary shaft 36 is fixed to the fixed disk 32, the angle between the arm 31 and the arm 33, that is, the knee joint angle can be monitored. Since the rotating disk 34 receives pressure from the brake pad 39, a spacer 47 is provided so that no force is applied to the internal encoder 46 and the rotating disk 34 is not distorted. In FIG. 17, spacers are provided at two locations, but the number and position are not limited thereto. Information relating to the rotation angle of the rotating disk 34 detected by the encoder 46 is output from the encoder 46 to the control box at a predetermined sampling period using a wire passing through a rotating shaft (not shown) or wireless means.

  A control box 202 is fixed on the thigh belt 203 and is electrically connected to the lightweight disc brake device 30 via a cable wired along the arm 31. The control box receives a signal from a small power source for supplying power to the actuator, a pressure sensor provided in the lightweight brake device, and an encoder 46 in the disc brake device 30, and appropriately controls the power supply voltage. Is incorporated. The signal from the encoder in the present embodiment indicates information relating to the rotation angle of the rotating disk 34 output at a predetermined sampling period. As described above, since the knee joint angle of the wearer can be monitored based on the rotation angle, information regarding the knee joint angle can be easily obtained.

Hereinafter, operation | movement of the walking assistance apparatus 200 of a present Example is demonstrated.
As in the case of the second embodiment, the walking assist device 200 works so as to assist muscles that maintain a posture in which the knee joint is largely bent when the stairs are lowered. When the stairs are descended, it is observed that the knee is bent deeper than a certain angle by the signal from the encoder inside the disc brake device 30 and the knee joint angular velocity is more than a certain velocity. A signal is sent to the disc brake device so as not to be faster, and the brake is applied to slow down the disc. When extending the knee joint, turn off the brakes and try to extend the knee with the wearer's own power. Such control is performed by the same control as that shown in the second embodiment.

  In this way, since the wearer's force is used to move the foot, an actuator with an output greater than necessary is not required, so there is no risk of applying excessive force to the wearer and it is safe even if it is worn. . Moreover, since the disc brake device using the dielectric elastomer actuator used as a brake is lightweight, there is little burden even if it is mounted. In addition, passive assistive devices such as supporters are always resistant to bending the knee joint, so unnecessary force is also applied to the bending and stretching of the necessary joints, placing a burden on the wearer. Become. By mounting such an electric brake, a resistance force against bending the knee can be applied when necessary, so that the burden on the wearer can be avoided when the auxiliary force is unnecessary.

  The present invention is not limited to the above-described embodiments, and includes various modifications. For example, the above-described embodiments have been described in detail in order to explain the present invention in an easy-to-understand manner, and are not necessarily limited to those having all the configurations described. Further, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Further, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment. In addition, each configuration, function, conversion unit, calculation unit, and the like of the control box described above may be realized in hardware by designing a part or all of them, for example, with an integrated circuit.

1 ... Dielectric elastomer actuator,
2. Elastomer material,
3, 4 ... flexible electrode,
5 ... substrate,
6 ... Brake pads
7 ... fixed part,
8 ... Lubricating oil,
9 ... Moving object,
10 ... Brake device,
11, 37 ... case,
12, 13 ... opening,
14 ... Belt-like moving body,
15 ... Lid,
16 ... Power cable,
17 ... Signal cable,
18, 39 ... Brake pads,
19 ... Pressure sensor,
20 ... fixed part,
21 ... Linear bearing,
25, 26 ... substrate,
30 ... Disc brake device,
31, 33 ... arms,
32, 34 ... disk,
35 ... Brake part,
36 ... rotating shaft,
38 ... Dielectric elastomer actuator,
40 ... bearings,
41 ... fixed part,
42 ... Linear bearing,
43 ...
44 ... nails,
45 ... Pressure sensor,
46, 110 ... encoder,
47 ... Spacer,
100 ... walking assist device,
101 ... belt hoisting device,
102 ... Control box,
103 ... waist belt,
104 ... Belt,
105 ... below the knee belt,
111... Belt withdrawal amount conversion unit,
112 ... Belt withdrawal speed calculation unit,
113 ... Brake force calculation unit,
114 ... Brake force conversion unit,
115 ... Memory,
116 ... small power source,
200 ... walking assist device,
202 ... Control box,
203 ... Thigh belt,
205 ... below the knee belt,
206 ... Socket

Claims (15)

An electric brake device for braking movement of a moving body,
A brake pad pressed against the moving body, an electric actuator including a material that is deformed by an electric signal for pressing the brake pad, a pressure sensor for monitoring a braking force by the actuator, and an output from the pressure sensor The electric brake device is characterized by comprising a controller that determines the braking force by reading and a power source that controls the electrical signal output by the controller. The electric brake device according to claim 1,
An electric brake device characterized in that when the material deformed by the electrical signal is deformed in a certain direction by the electrical signal, the material is also deformed in a direction orthogonal thereto. The electric brake device according to claim 2,
The material that is deformed by the electrical signal is fixed to the electric brake device in at least one place,
The electric brake device according to claim 1, wherein at least one of the fixed positions is on a surface perpendicular to the direction when the material deformed by the electric signal is deformed in one direction by the electric signal. The electric brake device according to claim 3,
The electric brake device according to claim 1, wherein at least one of the fixed positions is on a surface of the material that is deformed by the electric signal, on a side opposite to the side facing the brake pad. The electric brake device according to claim 1,
The electric brake device, wherein the pressure sensor for monitoring the brake force of the brake pad is disposed on a side of the material deformed by the electrical signal opposite to the side facing the brake pad. . The electric brake device according to claim 3,
The pressure sensor for monitoring the braking force of the brake pad is fixed to the fixed position on the opposite side of the material deformed by the electrical signal from the side facing the brake pad. Electric brake device. The electric brake device according to claim 1,
An electric brake device comprising a structure that suppresses movement of the brake pad in the same direction as the moving direction of the moving body. The electric brake device according to claim 1,
The electric brake device, wherein the moving body is a moving body that moves linearly. The electric brake device according to claim 1,
The electric brake device, wherein the moving body is a rotating moving body. The electric brake device according to claim 9,
The brake pad installed at a position sandwiching the rotating moving body further includes a fixed disk installed on the opposite side of the brake pad of the electric actuator installed on the opposite side of the rotating moving body. And
The rotating moving body, the brake pad, the electric actuator, and the fixed disk have a disk shape with a hole that penetrates the rotation shaft at the center thereof, and the fixed disk is attached to the rotation shaft. An electric brake device characterized by being fixed. An auxiliary device for assisting a pedestrian,
A belt hoisting device for hoisting a walking assist belt;
An electric brake device comprising: a brake pad pressed against the belt; an electric actuator including a material deformed by an electric signal for pressing the brake pad; and a sensor for monitoring a braking force by the electric actuator;
A control box for controlling the electric brake device;
The control box determines the braking force based on a signal relating to a belt withdrawal amount from the belt hoisting device and an output signal from the sensor, and applies the determined braking force to the electric actuator so as to generate the determined braking force. An auxiliary device for controlling the electric signal. The auxiliary device according to claim 11,
The control box includes a controller that calculates the braking force based on the signal related to the belt withdrawal amount from the belt winding device and the output signal from the sensor, and the brake force calculated by the controller based on the braking force. An auxiliary device comprising a power source that outputs the electrical signal applied to the electric actuator. An auxiliary device according to claim 12,
The controller is
A belt withdrawal amount converter that outputs the belt withdrawal amount based on a signal related to the belt withdrawal amount from the belt winding device; and a belt withdrawal speed calculation unit that calculates a belt withdrawal speed based on the belt withdrawal amount. Auxiliary device characterized by that. An auxiliary device for assisting a pedestrian,
A fixed disk, a rotating disk rotatable with respect to the fixed disk, a brake pad pressed against the rotating disk, an electric actuator including a material that is deformed by an electric signal for pressing the brake pad, and the electric actuator An electric brake device comprising a sensor for monitoring the braking force applied;
A control box for controlling the electric brake device;
The control box determines the braking force based on a signal related to a rotation angle of the rotating disk from the electric brake device and an output signal from the sensor, and generates the determined braking force. An auxiliary device that controls the electrical signal applied to the actuator. An auxiliary device according to claim 14,
The rotating disk and the fixed disk each have an arm,
The auxiliary device characterized in that the arm of the rotating disk and the fixed disk can be fixed to a thigh belt fixed to a thigh of a pedestrian and a lower knee belt fixed to a lower knee.

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