JPH10338141A - Driving-assisted small vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify equipment constitution for generating auxiliary driving force and to generate auxiliary driving force even during operation of turning a small vehicle. SOLUTION: A driving-assisted small vehicle is provided with a first and a second lateral driving wheels 11, 12 orthogonal to a proceeding direction, a first electric motor 15 connected to the first driving wheel 11 and a second electric motor 16 connected to the second driving wheel 12 so as to rotate the first and second driving wheels 11, 12 independently and to generate auxiliary driving force to the first and second driving wheels 11, 12, and one driving part 17 series-connected to the first and second electric motors 15, 16 and feeding the same current to both motors 15, 16 to generate the same torque.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small vehicle with a driving assist which generates an auxiliary driving force in accordance with an operating force of an operator and assists transportation by human power.

[0002]

2. Description of the Related Art Conventionally, a small vehicle for transportation used for manual transportation is provided with a battery power source, a motor, and the like, and a motor for assisting manual operation and reducing the labor of an operator. For example, there is an apparatus that outputs an auxiliary driving force.

[0003] In such a small vehicle, the output of the auxiliary driving force is controlled according to the condition of transportation by the vehicle. For example, the operation force to be applied to the small vehicle is different between the case where the small vehicle is pushed up while moving forward on an uphill and the case where the small vehicle is pushed on a flat road. Therefore, an operation force of an operator applied to an operation unit such as a steering wheel of the vehicle is detected, and an auxiliary driving force corresponding to the operation force is generated. For example, when moving forward on an uphill, the operator strongly presses the operation unit, so that a large auxiliary driving force corresponding to a large operation force is generated.

[0004]

By the way, the operation direction of the operator is not limited to the forward or backward traveling while traveling straight, but also the forward or backward traveling with turning. Since the operating force applied to the operation unit by the operator during turning is non-uniform, when trying to generate an auxiliary driving force corresponding to the non-uniform operating force, the left and right operating forces are separately detected. It is conceivable to adopt a configuration in which a motor and a drive unit are provided independently for each of the left and right wheels.

[0005] However, if the motor and the drive unit are provided independently for each of the left and right wheels, two sets of the motor and the drive unit are required, resulting in a problem that the equipment configuration becomes complicated. When a common motor and drive unit are provided for the left and right wheels, a switch for turning on and off the auxiliary driving force may be operated so that the auxiliary driving force does not work during turning. The operability at the time of turning becomes worse.

Therefore, the present invention provides a small vehicle with driving assistance which can simplify the device configuration for generating the auxiliary driving force and can generate the auxiliary driving force even when the small vehicle is turned. The purpose is to:

[0007]

According to a first aspect of the present invention, there is provided a driving assist device for generating an auxiliary driving force corresponding to an operating force applied by a push-pull operation of an operator. A small vehicle with a first and second drive wheels in a left-right direction perpendicular to a traveling direction;
A first electric motor connected to the first drive wheel and a second electric motor connected to the second drive wheel so as to rotate the second drive wheels independently and generate auxiliary driving force therewith. And one drive unit connected in series to the first and second electric motors and supplying the same current to them to generate the same torque.

According to a second aspect of the present invention, there is provided a small-sized vehicle with driving assistance which travels by an operating force applied by an operator's push-pull operation, the magnitude of the operating force applied by the operator and its forward or backward direction. An operation unit provided with a detection unit for detecting the driving direction, first and second driving wheels in a left-right direction perpendicular to the traveling direction, and a first torque for driving the first driving wheel by outputting a predetermined torque with a predetermined current. An electric motor and a second electric motor for driving the second drive wheel, and supplying the predetermined current for generating an auxiliary driving force according to the magnitude of the operation force detected by the operation unit and its forward or backward direction. And one drive unit connected in series to the first and second electric motors.

[0009]

1 to 4 show an embodiment of the present invention.
This will be described with reference to FIG. First, an overall configuration of a small vehicle with driving assistance according to the present invention (hereinafter, referred to as “small vehicle”) will be described with reference to FIG. FIG. 1 is a perspective view of a configuration example of a small vehicle. The small vehicle 1 shown in FIG. 1 includes a vehicle body 2 covered by a vehicle body cover 4 and an operation unit 3 including a steering wheel 5 and the like.

The vehicle body cover 4 is a member for covering the equipment provided in the small vehicle 1 such as the electric motor and its control device, and the upper part thereof serves as a carrier table for placing a load. I have. An operation panel 7 is provided near the handle 5 of the vehicle body cover 4. The handle 5 as a part of the operation unit 3 is connected to a frame structure of the vehicle body 2 via a coupling member 8 (not shown) in the vehicle body cover 4. The handle 5 has a U-shape in which the left and right sides are symmetrical. A detection unit 6 for detecting the magnitude of the operation force applied by the operator and the forward or backward direction is provided at the base end of the handle 5. Is provided.

A first drive wheel 11 is provided on the vehicle body 2 in a left-right direction on the side close to the steering wheel 5 and orthogonal to the traveling direction.
And the second drive wheel 12 are attached. Note that 13
Is a free wheel that is rotatable and located on a side away from the steering wheel 5, and one or two wheels are attached to the vehicle body 2.

The first drive wheel 11 has a first electric motor 1
5 is connected to the second drive wheel 12 and the second electric motor 1
6 are connected. The first electric motor 15 and the second electric motor 16 are connected in series to one drive unit 17. The driving unit 17 is connected to one power supply 18. The first electric motor 15 and the second electric motor 16 are P
Any device that can control torque using a battery as a power source, such as an M (permanent magnet) field motor, may be used.

FIG. 2 is a block diagram showing the configuration of the driving unit 17 described above. In the figure, a detecting unit 6 averages the outputs V _PR and V _PL of potentiometers (not shown) provided on the left and right sides of the steering wheel, and outputs the operating force applied to the steering wheel. The magnitude of the operating force is known from the magnitude of the average value of the outputs V _PR and V _{PL. If} the average value of the outputs V _PR and V _PL is positive, the operating force acts in the forward direction, and the outputs V _PR and V _PL When the average value of is negative, it is understood that the operating force is acting in the reverse direction. The setting device 7 is for setting the ratio of the auxiliary driving force to the detected operation force to, for example, large, medium, or small. For example, in the case of an uphill, the ratio of the auxiliary driving force is set to be large, and in the case of a flat road, the ratio of the auxiliary driving force is set to be small.

The driving section 17 includes an assist ratio calculating section 51, a subtractor 52, a proportional setting section 53, a PWM ratio converting section 54, a motor driver 55, a driving force converting section 56, and a voltage converting section 5.
7 and a vehicle speed calculator 58.

The assist ratio calculating section 51 includes an operating force detecting section 6
The ratio of the auxiliary driving force to the operating force is set based on the output related to the operating force from the controller and the output related to the setting from the setting device 7, for example, the auxiliary driving force corresponding to 1/2 of the operating force. A torque command value τ for generating a force is output to the subtractor 52. The subtracter 52 calculates a difference between the input torque command value τ and an output value of a voltage converter 57 described later. The proportional control unit 53 performs proportional control on the output of the subtractor 52. PWM (Pulse Width Modul
ation) The ratio conversion unit 54 changes the modulation ratio of the pulse width modulation signal according to the output of the proportional control unit 53.

The motor driver 55 receives a first electric motor 15 and a second electric motor 16 from the power source 18 based on the pulse width modulation signal output from the PWM ratio converter 54.
Control the current supplied to the The current direction is determined by the positive or negative value of the torque command value τ. If the current direction is positive, the current flows in such a manner as to generate forward driving torque, and if negative, the current flows in reverse.

The driving force conversion unit 56 includes a first electric motor 15
And the current supplied to the second electric motor 16 is detected,
The driving force is converted into a combined driving force value of the first driving wheel 11 and the second driving wheel 12 and output to the assist ratio calculating unit 51. The voltage conversion unit 57 converts the voltage into a voltage corresponding to the driving force value output from the driving force conversion unit 56 and outputs the voltage to the subtractor 31.

Reference numerals 59 and 60 denote tachometers for detecting the rotational speeds of the first electric motor 15 and the second electric motor 16, respectively. The vehicle speed calculation unit 58 issues a command to reduce the assist ratio, for example, in accordance with the calculated vehicle speed, based on the rotation output from the tachometers 59 and 60, for example.
Used when output.

Next, the operation of the above-described small vehicle will be described. FIG. 3 illustrates the movement of the small-sized vehicle 1 when the vehicle moves from going straight in the direction of arrow a to turning in the direction of arrow b. In straight a, the force F _R, F _L acting on the left and right of the handle 5 are the same. In response to the force F _R = F _L , the current i for generating a predetermined auxiliary driving force is changed by the first and second electric motors 1.
5 and 16 and the same torque is generated on the first and second wheels 11 and 12. Since the first and second driving wheels 11 and 12 have the same rotation speed, the same auxiliary driving force is generated in the first and second driving wheels 11 and 12 and the straight traveling a is maintained.

[0020] When moving from straight a the turning b, the force F _R of the turning radius smaller side of the left and right of the handle 5 is reduced, the force F _L of the rotation radius larger side increases. Regardless of the left and right imbalance forces F _R and F _L , the average value is applied to the control system as a predetermined torque command value via the assist calculation unit 51. First and second electric motors 15, 1
6 has the armature circuits connected in series and has a common control system, so that the same current always flows and generates the same torque.
That is, the auxiliary driving force acting on the first and second driving wheels 11 and 12 is equal in any case, and the first and second driving wheels 11 and 12 are allowed to rotate separately, so that the left and right unbalanced. force F _R, F _L and the first difference is the first intact resistance of the second drive wheel 11 and 12, it appears as a rotational speed difference of the second drive wheel 11, 12. Therefore, the turning of the vehicle is determined by the left and right imbalance of the human power, and the turning operation can be performed without any uncomfortable feeling although there is a basic auxiliary driving force.

Next, an example of a mechanism of the operating section 3 for separately detecting operating forces when different forces act on the left and right of the handle will be described with reference to FIG. FIG. 4A is a top view of the periphery of the handle 5, and FIG. 4B is a side view.

The operation unit 3 has a left part and a right part symmetrical with respect to the central axis 45. The operation unit 3
A handle 5 to which an operating force by an operator is applied, a potentiometer 30 provided to extend from both ends of the handle 5, and a coupling member 8 provided to incorporate the handle 5 and the potentiometer 30 are provided. .

The connecting member 8 includes a plurality of bolts 41.
1 is constituted by two flat plates 28 and 29 fixed so as to face each other at a predetermined interval. Flat plate 2
Holes each having a predetermined diameter are formed on both left and right sides of the handle 8 and 29, so that a handle shaft 5a and a potentiometer 30 provided to extend from the tip of the handle shaft 5a can be incorporated. FIG.
As shown in (b), the connecting member 8 is connected to the vehicle body cover 4 via the flat plate 29.

The handle 5 has a shape in which a cylinder having the same diameter is curved in a U-shape.
A handle shaft 5a is provided so as to extend from the handle shaft 5a. The handle shaft 5a is provided with two springs 21 and 22 on its outer periphery, and the springs 21 and 22 are separated by a spring pin 23.
The other ends of the springs 21 and 22 with respect to the pin 23 are fixed by snap rings 24 and 25. Spring 2
1 is fixed to a fixing spacer 26.
To the handle shaft 5a.
The snap ring 25 is fixed at a predetermined position with respect to the flat plate 28 by the spacer 27, and can be relatively moved with respect to the handle shaft 5a. When no operating force is applied to the handle 5, the springs 21 and 22 are in a natural length state, and the position of the shaft 5a in the front-rear direction is at the neutral position OO '.

The potentiometer 30 is a member for detecting the operation direction and the operation force on the handle 5, and a so-called linear potentiometer is used. One potentiometer 30 is provided on each of the right and left portions of the handle 5 (hereinafter, when it is necessary to distinguish between the right portion and the left portion corresponding to the two potentiometers, it is provided on the right side). The potentiometer is represented by 30R, and the one provided on the left side is represented by 30L). The potentiometer 30 can be moved in the front-rear direction as indicated by an arrow 31 in response to the movement of the shaft 5a associated with the operation of the handle 5 with the displacement element 30a provided therein,
The internal electric resistance value changes in accordance with the movement of the deflector 30a.

The relationship between the operation of the handle 5 by the operator and the movement of the potentiometer 30 corresponding thereto is as follows. When the handle 5 is operated so as to be pushed in the forward direction as indicated by 32, the handle shaft 5a moves in the forward direction from the neutral position OO 'while the springs 21 and 22 contract. Then, the deflector 30a moves in response to the movement of the left and right shafts 5a, and the potentiometer 30
The resistance value inside corresponds to the position of the shaft 5a. Thereby, the resistance value inside the potentiometer 30 becomes a value corresponding to the operation force applied to the handle 5 in the operation direction.

Also, when the operation applied to the handle 5 is an operation to pull in the reverse direction, the spring 2
The deflector 30a moves in response to the movement of the left and right shafts 5a in the backward direction while the first and second 22 extend, and the resistance value inside the potentiometer 30 corresponds to the operation force applied to the handle 5 in the operation direction. Value.

A case where an operating force in the turning direction is applied to the steering wheel 5 so as to turn the small vehicle 1 will be described. When an operation of pushing the handle 5 in the forward direction is applied so that, for example, the operation force on the left portion of the handle 5 becomes larger than the operation force on the right portion,
The small vehicle 1 can be turned rightward while moving forward. When such an operating force is applied to the handle 5, the handle shaft 5a is located in the forward direction from the neutral position, and the left shaft 5a is located before the right shaft 5a. The turning direction is determined according to the difference between the relative positions of the right and left shafts in the front-rear direction. That is, the angle θ formed by the left shaft, the right shaft, and the neutral position OO ′ corresponds to the turning angle of the small vehicle. Further, the resistance values of the potentiometers 30R and 30L provided on the left and right are respectively values corresponding to the positions of the left and right shafts 5a. In this way, the left and right operation forces acting on the operation unit 3 can be detected independently.

[0029]

According to the first or second aspect of the present invention, the inner ring receiving relatively high acting force from the ground rotates at a low rotational speed when the vehicle is turning. , And the outer ring having relatively low acting force from the ground rotates at a high rotation speed. Therefore, the operator does not reduce the traveling speed of the vehicle, etc.
The operation of turning the small vehicle can be performed smoothly.
In addition, in order to smoothly perform turning traveling, it is not necessary to perform a control such as lowering an auxiliary driving force by lowering an auxiliary ratio to lower a traveling speed, so that a control system is complicated. Not even.

[Brief description of the drawings]

FIG. 1 is a perspective view of a small vehicle with driving assistance.

FIG. 2 is a diagram showing a block configuration of a control system of a small vehicle with driving assistance.

FIG. 3 is a diagram illustrating an operation of a small vehicle when turning.

FIG. 4 is a diagram showing an operation unit provided in the small vehicle.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Small vehicle 2 Vehicle main body 3 Operation part 5 Handle 11 1st drive wheel 12 2nd drive wheel 15 1st electric motor 16 2nd electric motor 17 Drive part 18 Power supply

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Masayoshi Kang 100 Takegahana-cho, Ise-shi, Mie Shinko Electric Co., Ltd. Ise Office (72) Inventor Katsumi Miyata 100-Takegahana-cho, Ise-shi Mie Prefecture Inside

Claims (2)

[Claims] 1. A small vehicle with driving assistance for generating an auxiliary driving force in accordance with an operating force applied by an operator's push / pull operation, comprising: first and second driving wheels in a lateral direction orthogonal to a traveling direction; The first and second driving wheels are independently rotated, and the first and second driving wheels are generated so as to generate an auxiliary driving force.
A first electric motor connected to a driving wheel and a second electric motor connected to the second driving wheel; connected in series to the first and second electric motors; And a drive unit that generates the torque of 2. A small vehicle with driving assistance which runs by an operation force applied by an operator's push-pull operation, wherein a detection unit for detecting the magnitude of the operation force applied by the operator and its forward or backward direction is provided. An operation unit provided, first and second drive wheels in a lateral direction orthogonal to a traveling direction, a first electric motor that outputs a predetermined torque with a predetermined current to drive the first drive wheel, and the second electric motor. A second electric motor that drives a driving wheel; and a first electric motor that supplies the predetermined current for generating an auxiliary driving force according to a magnitude of an operation force detected by the operation unit and a forward or backward direction thereof. And one driving unit connected in series to the second electric motor.