JP2001104418A - Braking device for walking cart - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a braking device by which running load during running at a low speed is decreased without spoiling safety of a walking cast, as a walking support tool. SOLUTION: By contacts of relays RY1-RY4 which are not actuated when running speed of a walking cart does not reach a specified value, but are actuated when it reaches at least the specified value, a power generation damping force is generated by shortcircuiting between wires of electric elements 11R-11R of an electricity generators on the left and right of the cart body.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a walking vehicle used by a person who has difficulty walking in a healthy state to support the body during walking.

[0002]

2. Description of the Related Art For example, in a conventional walking vehicle (walking assist device) disclosed in Japanese Patent Application Laid-Open No. 10-305067, a metal rotating plate is provided at an end of a rotating shaft of a wheel. Permanent magnets are arranged so as to be sandwiched from both sides. When the rotating plate rotates while linking with the magnetic flux due to the rotation of the wheel, an eddy current is generated in the rotating plate, and rotation resistance is generated. Therefore, a load characteristic in which the rotational resistance increases and decreases in accordance with the increase and decrease in the rotation speed of the wheel can be obtained.

[0003]

The conventional walking vehicle as described above is designed so that a predetermined braking force can be obtained at a predetermined speed in order to prevent danger, and the level of the predetermined speed is set low. . Therefore, there is a problem that a certain running load is applied even when the vehicle is running at a low speed lower than the predetermined speed, which burdens the user. On the other hand, when the walking vehicle is used for rehabilitation, it is necessary to apply a certain running load to the user even during low-speed running.

[0004] In view of the above-mentioned conventional problems, an object of the present invention is to provide a braking device that reduces a traveling load during low-speed traveling without impairing the safety of a walking vehicle. Another object of the present invention is to provide a braking device for a walking vehicle that can generate a certain traveling load when traveling at a low speed, if necessary.

[0005]

SUMMARY OF THE INVENTION The present invention is a braking device mounted on a walking vehicle that travels by pushing while walking by a user. The braking device controls the rotation speed of the wheel in conjunction with the wheel of the walking vehicle. A walking vehicle braking device comprising: a power generating device that generates a corresponding voltage; and an opening / closing unit that forms a short-circuit closed circuit including the power generating device only when a generated voltage of the power generating device is equal to or higher than a predetermined value ( Claim 1). In the braking device for a walking vehicle configured as described above, when the rotation speed of the wheels, that is, the traveling speed of the walking vehicle becomes a predetermined value or more, and the power generation voltage of the power generation device becomes a predetermined value or more, the open / close means closes the short circuit. A circuit is formed, and a current flows due to the electromotive force of the power generator. When the current flows, a power generation braking force is generated, and the walking vehicle is decelerated. Therefore, traveling at a traveling speed equal to or higher than the predetermined value is suppressed. On the other hand, if the traveling speed is lower than the predetermined value, the short-circuit closed circuit is not formed. Therefore, the running load during low-speed running is small.

In the above braking device, the opening / closing means is a relay, and includes a variable resistor that adjusts a DC voltage V1 based on a voltage generated by the power generator to a DC voltage V2 and applies the DC voltage to a coil of the relay. (Claim 2). In this case, when the DC voltage V2 becomes equal to or higher than the minimum operating voltage of the relay, the relay operates and its contact forms a short-circuit closed circuit. Further, by adjusting the variable resistor, the generated voltage and the traveling speed corresponding to the minimum operating voltage of the relay are set.

[0007] The braking device (claim 1) may include a variable resistor that is always connected to the power generator and forms a resistive load circuit (claim 3). In this case, by setting the resistance value of the variable resistor high, the current flowing through the variable resistor due to the electromotive force of the power generator can be suppressed to a small value. Therefore, when the vehicle is running at low speed, almost no power generation braking force is generated, and the burden on the user is small. Also,
If necessary, by setting the resistance value of the variable resistor low, it is possible to generate a certain amount of dynamic braking force and use it to apply an appropriate running load to the user.

[0008]

2 to 4 are drawings showing a walking vehicle equipped with a braking device according to a first embodiment of the present invention. FIG. 2 is a side view (right is forward, left is rear). FIG. 3 is a rear view, and FIG. 4 is a plan view. In FIGS. 2 to 4, a frame 1 of a walking vehicle includes a substantially horseshoe-shaped base pipe 2, a front pipe 3 erected from the front center of the base pipe 2,
Side pipes 4 erected from the right and left rear ends of the base pipe 2, a horizontal U-shaped guard pipe 5 connecting the two side pipes 4 and the front pipe 3, and left and right sides of the base pipe 2 It comprises a reinforcing pipe 6 connecting the end side and the front pipe 3, and a horizontal U-shaped arm pipe 7 connecting each upper end of the side pipe 4 and the upper end of the front pipe 3. On the arm pipe 7, an arm rest member 8 made of a U-shaped cushion material is attached. The front pipe 3 and the side pipe 4 are each configured by connecting two pipes, and the height of the arm placing member 8 can be adjusted by loosening the adjusting screw 9.

A pair of left and right casters 10 are mounted on the front side of the base pipe 2 of the frame 1. A pair of right and left power generators (substantially structured three-phase brushless motor having a speed reduction mechanism) are provided behind the base pipe 2.
11 is attached, and the rotating shaft 11 a
The wheel 12 is attached to the. The power generator 11 on the right side in the traveling direction of the walking car is connected via a cable 13 (FIG. 2).
It is connected to an operation switch box 14 mounted on the base pipe 2. The power generator 11 on the left side in the traveling direction of the walking vehicle is connected to the operation switch box 14 via a cable 15 (FIG. 3) wired along the reinforcing pipe 6. Operation switch box 14
As shown in FIG. 4, the main switch 14
1 and a resistance adjusting knob 142, and a circuit described later is provided therein. The main switch 141 and the resistance adjustment knob 142 are arbitrarily operated by a user or the like.

FIG. 1 is a circuit diagram of a braking device in the above-mentioned walking vehicle. In the figure, the armature in the power generator 11 on the right side of the vehicle body is denoted by 11R, and the armature in the power generator 11 on the left side of the vehicle body is denoted by 11L. When the walking vehicle runs by the user walking while pushing the walking vehicle, the wheel 1
2, the rotor (not shown), which is the rotating field of the power generator 11, rotates, and a power generation voltage (three-phase alternating current) is generated in the armatures 11R and 11L in accordance with the rotation speed of the wheels 12. In the armature 11R on the right side of the walking car, the coil 1
The variable resistor 143 and the contact a of the relay RY1 are connected between the two-phase wires 1Ra and 11Rb. The variable resistor 144 and the contact a of the relay RY2 are connected between the two-phase wires of the coils 11Rc and 11Rb. Similarly, in the armature 11L on the left side of the walking vehicle, the coil 11La
The variable resistor 145 and the a-contact of the relay RY3 are connected between the two-phase wires of L and 11Lb. Also, the coil 11L
The variable resistor 146 and the contact a of the relay RY4 are connected between the two-phase wires c and 11Lb. Each variable resistor 14
3 to 146 are simultaneously adjusted to the same resistance value in conjunction with the resistance adjustment knob 142.

Each phase voltage of the armature 11R is supplied to a rectifier circuit RC1 including rectifiers 51 and 52. Further, each phase voltage of the armature 11L is supplied to a rectifier circuit RC2 including rectifiers 53 and 54. Via the main switch 141, the Zener diode 55, the smoothing capacitor 56 and the voltage regulator 57 are connected to the electric circuits L1 and L2, which connect the outputs of the two rectifier circuits RC1 and RC2 in common.
Is connected. A capacitor 59 and a variable resistor 60 and a fixed resistor 61 are connected via a rectifier 58 between the electric circuits L3 and L4 on the output side of the voltage regulator 57. A relay R is provided between the electric circuit L5 connected to the intermediate terminal of the variable resistor 60 and the electric circuit L4.
Y1, RY2, RY3 and RY4 are connected. The variable resistor 60 is provided to step down the DC voltage applied to both ends of the capacitor 59 within a certain range and output the same.

Next, the operation of the walking vehicle configured as described above will be described. The walking vehicle may be used with the main switch 141 turned on (closed) or off (opened). First, the operation when the main switch 141 is turned on will be described. When the user places his arm on the arm placing member 8 and walks while pushing the walking car, the armatures 11R and 1R are moved in accordance with the traveling speed.
An electromotive force of three-phase alternating current is generated in 1 L. A current flows through the variable resistors 143 to 146 by this electromotive force. Armature 11R
And 11L, a power generation braking force that hinders the rotation of each rotor is generated. Here, the dynamic braking force is proportional to the current. Therefore, in a state where a constant electromotive force (generated voltage) is generated, the variable resistors 143 to 143 are output.
When the resistance value of 146 is reduced, the current increases, and the power generation braking force increases. Also, when the resistance values of the variable resistors 143 to 146 are increased, the current decreases, and the power generation braking force decreases. Therefore, by operating the resistance adjusting knob 142, a desired dynamic braking force can be obtained in accordance with the traveling speed. Normally, the resistance values of the variable resistors 143 to 146 are set to be high, so that the dynamic braking force hardly works at low speed traveling.

On the other hand, the AC voltages generated in the armatures 11R and 11L are rectified by rectifier circuits RC1 and RC2, respectively, smoothed by a smoothing capacitor 56, and supplied to a voltage regulator 57. Here, the voltage regulator 57 outputs the voltage V1 with the fluctuation suppressed. This voltage V1 is applied to a capacitor 59 via a rectifier 58 for preventing backflow. The voltage V1 is also applied to a series body of the variable resistor 60 and the fixed resistor 61. The applied voltage V1 becomes a voltage V2 (≦ V1) according to the set position of the intermediate terminal of the variable resistor 60, and the voltage V2 is applied between the electric circuits L5 and L4.

When the voltage V2 is lower than the minimum operating voltage of the relays RY1 to RY4, the relays RY1 to RY4 do not operate. Therefore, the contacts of the relays RY1 to RY4 provided in parallel with the variable resistors 143 to 146 are open. When the running speed of the walking vehicle increases to a predetermined value or more, the generated voltage becomes equal to or more than the predetermined value, and based on the generated voltage, the voltages V1 and V2 increase, and the voltage V2 changes to
When the voltage exceeds the minimum operating voltage of 1 to RY4, the relay RY1
RY4 operate to close each contact. As a result, the armatures 11R and 11L are short-circuited between the three-phase wires, and the current is maximized. Therefore, the maximum power generation braking force is generated for the traveling speed at that time, and the walking vehicle is decelerated at a stretch. Because this dynamic braking force is strong,
If it is level, it will be almost stopped.

Even if the generated voltage drops below a predetermined value due to the deceleration and the voltage V1 drops, the electric charge stored in the capacitor 59 causes a CR discharge circuit between the variable resistor 60 and the fixed resistor 61. Formed, and for a certain period of time, the electrical circuit L5-L
4, a voltage that can maintain the operation state of RY1 to RY4 remains. Then, after a certain time, this voltage is applied to the relays RY1 to RY1.
If the voltage becomes lower than the minimum operation maintaining voltage of RY4, the relay RY1
RY4 are opened, and the line-to-line short-circuit state is released.
Thus, the relay RY1 is controlled by the capacitor 59.
RY4 can perform an off-delay operation.
For example, on a downhill, even after the maximum dynamic braking force is generated and decelerated, there is a possibility that the operation of accelerating again and generating the dynamic braking force when the dynamic braking force is lost may be repeated. The above-described off-delay operation that delays repetitive responsiveness can prevent chattering of the contacts of relays RY1 to RY4.

The peak value of the voltage rectified by the rectifier circuits RC1 and RC2 is
Is limited by Therefore, even if a voltage exceeding the zener voltage of the zener diode 55 is applied due to an increase in the traveling speed, overvoltage of the circuit downstream (right side) of the zener diode 55 is prevented, and the voltages V1 and V2 are each limited to a predetermined value or less. Is done.

As described above, when the running speed of the walking vehicle becomes equal to or higher than the predetermined value, the maximum braking force at the running speed acts, and the walking vehicle is decelerated. Here, the generated voltage and the traveling speed corresponding to the minimum operating voltage of the relays RY1 to RY4 are set by setting the variable resistor 60. Therefore, it is possible to arbitrarily set the traveling speed at which the maximum dynamic braking force is generated within a certain range. Further, the power generation braking force before the maximum power generation braking force is generated can be freely obtained by adjusting the variable resistors 143 to 146. By operating one resistance adjusting knob 142, all the variable resistors 143 to 146 are simultaneously adjusted to the same value, so that an equal dynamic braking force can be applied to each wheel 12.

On the other hand, when the main switch 141 is turned off, a circuit subsequent to the main switch 141 does not operate due to the opening of the main switch 141.
The relays RY1 to RY4 do not operate. As a result, even if the traveling speed of the walking vehicle increases, no strong dynamic braking force is generated due to the short circuit between the lines, and the dynamic braking force is generated only by the variable resistors 143 to 146. An increasing / decreasing dynamic braking force can be obtained. Therefore, for example, when a healthy person moves a walking vehicle, by turning off the main switch 141, the walking vehicle can be moved quickly without generating a strong dynamic braking force.

In the above-described embodiment, the left and right wheels 12 correspond to the rotating shafts 11a of the corresponding power generators 11, respectively.
It is connected to the. Therefore, an axle connecting the left and right wheels is unnecessary. Further, even when there is a difference in rotation speed between the left and right wheels 12, a power generation braking force corresponding to each rotation speed is obtained, so that it is unlikely that one of the wheels 12 rotates faster than the other. Therefore, turning of the vehicle body during braking can be suppressed. On the other hand, the relays RY1 to RY4 are connected between the common electric circuits L5 to L4, and the operation timing is simultaneous. Therefore, a strong power generation braking force due to the line-to-line short circuit is simultaneously generated on the left and right wheels 12, and the walking vehicle is decelerated without losing the balance between the left and right braking forces.

On the other hand, when a walking vehicle equipped with the braking device of the above embodiment is used for rehabilitation, a certain amount of braking force is generated by setting the resistances of the variable resistors 143 to 146 low. Thus, an appropriate walking load can be applied to the user. In this case, if the main switch 141 is turned on, a speed limit can be imposed. If the main switch 141 is turned off, a load can be applied by the power generation braking force that increases according to the traveling speed.

FIG. 5 is a circuit diagram showing a braking device for a walking vehicle according to a second embodiment. The difference from the first embodiment is that the variable resistors 143 to 146 and the resistance adjustment knob 142 shown in FIG. 1 are omitted.
This is the same as the embodiment. In the circuit shown in FIG. 5, when the main switch 141 is turned on and the traveling speed exceeds a predetermined value, the contacts of the relays RY1 to RY4 are closed and a strong power generation braking force is obtained in the same manner as in the first embodiment. However, when the traveling speed is less than the predetermined value, no traveling load is generated. When the main switch 141 is turned off, a closed circuit including the armatures 11R and 11L cannot be formed, so that no current flows and no power generation braking force is generated. Therefore, when a healthy person moves the walking vehicle, the main switch 141 is turned off so that the power generation braking force is not generated, so that the walking vehicle can be moved quickly and easily.

In the above embodiments, the relays RY1 to RY1
The RY4 is an opening / closing unit that forms a short-circuit closed circuit for the armatures 11R and 11L, and is used as an opening / closing unit that also operates as a voltage detector that operates with a voltage based on a predetermined generated voltage. Note that a circuit having a similar function can be configured by using a semiconductor switching element or the like instead of these relays RY1 to RY4.

[0023]

The present invention configured as described above has the following effects. According to the braking device for a walking vehicle of claim 1,
When the rotational speed of the wheels, that is, the traveling speed of the walking vehicle becomes equal to or more than a predetermined value, a power generation braking force is generated, and the walking vehicle is decelerated.
It is safe. On the other hand, if the traveling speed is lower than the predetermined value, a short-circuit closed circuit is not formed, and the traveling load during low-speed traveling is small. Therefore, the traveling load during low-speed traveling can be reduced without impairing safety.

According to the second aspect of the present invention, the power generation voltage and the traveling speed corresponding to the minimum operating voltage of the relay are set by adjusting the variable resistor. The traveling speed at which the braking force is generated can be arbitrarily set within a certain range. Therefore, a braking force can be generated in accordance with the walking ability of the user.

According to the third aspect of the present invention, by setting the resistance value of the variable resistor high, the current flowing through the variable resistor due to the electromotive force of the power generator can be suppressed to a very small value. On the other hand, when the vehicle is running at a low speed, almost no power generation braking force is generated, and the burden on the user can be reduced. Also, if necessary, if the resistance value of the variable resistor is set low, a certain amount of braking power is generated,
Since it can be used to apply an appropriate running load to the user, the walking vehicle can also be used for rehabilitation.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a braking device for a walking vehicle according to a first embodiment of the present invention.

FIG. 2 is a side view of a walking vehicle equipped with the braking device.

FIG. 3 is a rear view of the walking vehicle.

FIG. 4 is a plan view of the walking vehicle.

FIG. 5 is a circuit diagram showing a braking device for a walking vehicle according to a second embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 frame 11 power generation device 12 wheels 60 variable resistor 61 fixed resistor 143 to 146 variable resistor RC1, RC2 rectifier circuit RY1 to RY4 relay

Claims (3)

[Claims] 1. A braking device mounted on a walking vehicle that travels by pushing while walking by a user, wherein the power generating device generates a voltage corresponding to a rotation speed of the wheel in conjunction with a wheel of the walking vehicle. And a switching device for forming a short-circuit closed circuit including the power generation device only when a generated voltage of the power generation device is equal to or higher than a predetermined value. 2. The walking device according to claim 1, wherein said opening / closing means is a relay, and includes a variable resistor which adjusts a DC voltage V1 based on a voltage generated by said power generating device to a DC voltage V2 and applies the voltage to a coil of said relay. Car braking device. 3. The braking system for a walking vehicle according to claim 1, further comprising a variable resistor which is constantly connected to said power generator and forms a resistance load circuit.