JPH03222603A - Neutral detecting device of operating lever for motor car - Google Patents

Abstract

PURPOSE:To improve durability by disposing a proximity switch, which can detect approach of the end of an operating lever in non-contacting state, at a position corresponding to the neutral position of the operating lever. CONSTITUTION:When a joy stick lever 1 is in neutral state, a photointerrupter 2 detects the state and provides an output higher than a predetermined level to a main controller 5 with a small time lag from the outputs of variable resistors 54, 55. The main controller 5 judges that the operation of the joy stick lever 1 is stopped based on the output from the photointerrupter 2 and provides a stop command to a brake means(not shown). Since the main controller 5 provides the stop command based on the outputs from the variable resistors 54, 55, under a state where the speed of a motor car has dropped, the motor car can stop without causing considerable impact.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a neutral detection device for a control lever for an electric vehicle, and in particular, a device for detecting neutrality in the 36° direction of a joystick controller of an electric wheelchair or the like. The present invention relates to a neutral detection device for an operating lever for an electric vehicle, which is suitable for detecting neutrality of a tiltable joystick lever (having two degrees of freedom).

[Background technology]

Electric vehicles such as electric wheelchairs have a motor that is driven by a battery as a drive source, and the amount of rotation of the motor is controlled according to an accelerator signal, thereby driving the left and right rear wheels to rotate. The direction of the vehicle is changed (left and right) by turning the front wheels that are energized by the driving force of the vehicle.

As an accelerator device that generates this accelerator signal, a joystick controller having a joystick lever that can be tilted within a predetermined range in a 360° direction is usually used.

FIG. 7 shows this joystick controller in a simplified manner.

In this FIG. 7, the joystick lever 50 is
The first swing arm 51 is rotatable within a predetermined range around the X-axis in the figure, and the first swing arm 51 is rotatable within a predetermined range around the Y-axis (direction perpendicular to the page) perpendicular to the X-axis (arrow A- A
The distal end of the gimbal mechanism 53 is supported by a gimbal mechanism 53 consisting of a second swing arm 52 (see '), and has a structure capable of tilting within a predetermined range in a 360° direction. That is, the first and second swing arms 51 and 52 are made of plate-like members having a predetermined width and are formed in a substantially semicircular shape, and a longitudinal groove of a predetermined length is provided in the center of each of them. The tip of the joystick lever 50 is provided so as to pass through these. The base end of the joystick lever 50 is attached to a support member 59 shown in the figure via a universal joint 61. Furthermore, a grip portion 50A is provided at the base end of the joystick lever 50.

With this structure, the joystick lever 50 moves in the first and second directions in a 360° direction. Second swing arm 51, 52
The joystick lever 5o can be tilted within a range defined by the length of the groove formed in the joystick lever 5o, and the tilt of the joystick lever 5o in any direction is resolved into two orthogonal directions. It is detected as the rotation angle of the second swing arms 51 and 52.

However, in reality, the lever support part 60 to which the gimbal mechanism 53 is attached is installed inside the case body 7o with the X-axis and Y-axis shifted by 45 degrees from the state shown in the figure.

1st. The shaft portion of each of the second swing arms 51 and 52 has a first swing arm. First and second variable resistors 54 and 55 are respectively provided that output voltages proportional to the rotation angle of the second swing arm 51 and 52. These variable resistors 54 and 55 generate rotation control signals for the left wheel motor and the right wheel motor, respectively. Therefore, by tilting the joystick lever 50 in an arbitrary direction, the rotation control signals can be controlled in that direction. In addition to controlling the direction of the electric vehicle, it is also possible to control the traveling speed according to the magnitude of the inclination angle at that time.

FIG. 8 shows an example of electrical connection to the first variable resistor 54, where Rv is the resistance of the variable resistor 54, and R
, , R2 are each fixed resistances.

A power supply voltage ■ is applied across the resistors R1 and Rt. Apply.

FIG. 9 shows the characteristics of the output voltage v0 of the variable resistor 54 in the electrical connection shown in FIG. 8,
A linear voltage change occurs in the range of rotation angle -〇, ~ θ1,
It is shown that an output voltage of cc/2 can be obtained at the neutral position (rotation angle O). The second variable resistor 55 is also electrically connected in a similar manner so that similar output characteristics can be obtained.

Follow me, 1st. By electrically detecting that the output voltages of the second variable resistors 54 and 550 are both VC and /2, it is possible to detect that the lever is in the neutral state. This neutral position normally corresponds to a stop position in joystick lever operation, and therefore, in this position, the motor is configured to be in a stopped state in response to a neutral voltage.

In this case, as is clear from FIG.
Although the maximum resistance change region (effective limited region) can be obtained in the range of θ8, on the other hand, there is a problem that the region of neutral voltage V cc/2 is extremely narrow and operation is difficult.

As a method to solve this problem, as shown in FIG. If inputted into the absolute value amplifier 56, the corresponding voltage ■. ■ is the neutral voltage.

The voltage range smaller than this is output with its sign inverted, resulting in an absolute value output. 1st
Figure 1 shows the output voltage characteristics of the absolute value amplifier 56, which is minimum at the neutral position and exhibits a figure 7 shape in the range of rotation angle 2θ corresponding to the resistance change range of the variable resistor 54,55. generates an output that changes to .

Here, in FIG. 11, outside the range of rotation angle 2θ1, the absolute value output voltage VA determined by the absolute value amplifier 56
Causes BS. Therefore, the neutral region can be set by setting the neutral level indicated by the symbol in the figure.

In order to reduce the influence of uneven wear of As is clear from the voltage characteristics, the resistance change area (effective area) is inevitably narrowed, which is disadvantageous in terms of operability and feel.

[Problem to be solved by the invention]

However, in the method using the absolute value amplifier 56 in the conventional example, in order to accurately detect the neutral position, the voltage output characteristic is linear (normal state) as shown in FIG.
However, if the voltage output characteristics become as shown in Fig. 13 due to uneven wear of the resistive film over time,
The output V0° of the absolute value amplifier 56 becomes as shown in Fig. 14, and a motor rotation signal is output even though the joystick lever 50 is in the neutral position, so even if the stop operation is performed, the electric vehicle will not move. There was an inconvenience that it was dangerous because it did not stop. [Object of the Invention] The object of the present invention is to improve the inconveniences of the conventional example and, in particular, to provide a neutral detection device for a control lever for an electric vehicle that does not affect operability (and has excellent durability). Our goal is to provide the following.

[Means to solve the problem]

The present invention provides a gimbal-shaped support means that is supported at its distal end by a gimbal-shaped support means that is made up of a first support member that is rotatable around a predetermined axis and a second support member that is rotatable around an axis perpendicular to the one axis. The first and second variable resistors are equipped with an operating lever, and first and second variable resistors that are respectively installed on the shaft portions of the first and second support members and output voltages that are proportional to the rotation angle of each of the support members. In a neutral detection device for an operating lever for an electric vehicle, which is configured to detect this as a neutral position when a second variable resistor simultaneously outputs a predetermined voltage corresponding to a neutral position in each movable range. The structure is such that a proximity switch that can detect the approach of the tip without contact is installed corresponding to the neutral position of the operating lever. This aims to achieve the above-mentioned objective.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 5.

Here, regarding the same components as the conventional example described above,
The same symbols will be used.

FIG. 1 shows a simplified joystick controller equipped with a device according to this embodiment.

In FIG. 1, a joystick lever 1 serving as an operating lever has a first support member rotatable within a predetermined range around the X-axis in the figure, similar to the conventional example shown in FIG. A swing arm 51 and a second swing serving as a second support member that can rotate within a predetermined range around the Y axis (direction perpendicular to the plane of the paper) perpendicular to the X axis (see arrow A-A' in the figure). A gimbal mechanism 53 as a gimbal-like support means consisting of an arm 52 supports the distal end IA of the gimbal mechanism 53.
is supported. Further, the base end side of this joystick lever is attached to a support member 59 shown in the figure via a universal joint 61. Due to this structure, this joystick lever can be moved in the 360@ direction to the first position as shown in FIG. Second swing arm 51,5
It can be tilted within a range defined by the length of the groove formed in 2. However, in reality, it is the X axis.

Gimbal mechanism 5 with the Y-axis deviated by 45 degrees from the state shown in the figure.
The lever support part 60 to which 3 is attached is installed inside the case 70.

Said 1st. Similarly to FIG. The first swing arm 51,52 outputs a voltage proportional to the rotation angle of the second swing arm 51,52. A second variable resistor 54,55 is provided in each case. These variable resistors 54 and 55 each generate an accelerator signal as a rotation control signal for a left wheel motor and a right wheel motor, which will be described later.

Furthermore, in this embodiment, as shown in FIG. 1, a reflective photo as a proximity switch is provided on the bottom surface of the case 70 so as to face the end surface of the joystick lever 1 when the joystick lever 1 is in the neutral position. An interrupter (hereinafter referred to as a "photointerrupter") 2 is equipped. To explain this in more detail, as shown in FIG. is the angle α
A light emitting diode 3 arranged in such a manner that the light emitting diode 3 is located at a position that is line symmetrical to the light emitting diode 3 with respect to a perpendicular line H drawn from the intersection point A of the optical axis of the light emitting diode 3 and the end surface of the joystick lever 1 to the end surface. The phototransistor 4 is arranged in the phototransistor 4 shown in FIG. Therefore, when the joystick lever 1 is in the neutral state, the amount of light emitted from the light emitting diode 3 reflected by the end face of the joystay and the lever 2 reaches a maximum, and this is detected by the phototransistor 4. Therefore, when the level of the amount of reflected light exceeds a certain level, it can be determined that this is the neutral position of the gravity lever. Here, if one that emits infrared rays is used as the light emitting diode 3, external light (very little)
It is desirable to use such a material because it is less susceptible to the effects of dirt, dust, etc.

FIG. 3 shows the overall circuit configuration of this embodiment. In this figure, 1. Second variable resistor 54.5
The output of 5 is the 1st. The signals are input to the second signal processing circuit 6.7, each signal processed separately, and then input to the main controller 5. Further, the output of the photointerrupter 2 described above is input to the main controller 5 via the signal delay circuit 8. The output stage of the main controller 5 is connected to a right wheel motor (
Motor R)11. A left wheel motor L12 is provided. The signal processing circuits 6 and 7 are actually configured to include absolute value amplifiers (not shown) and the like provided corresponding to the variable resistors. Here, the electrical connections of the variable resistors 54 and 55 are the same as in FIG. 8 described above.

Next, the overall operation of this embodiment will be explained.

When the joystick lever l is tilted in any direction, the voltage corresponding to that direction and tilt angle becomes the first. They are output from the second variable resistors 54 and 55, respectively. After this output voltage is processed by the signal processing circuit 6.7, it is input to the main controller 5, and the main controller 5 determines the control amount for the motor R11 and motor L12 based on these signals, and performs drive control. Output the signal to the motor drive circuit 9.10.

As a result, the motor drive circuits 9 and 10 drive the motor R11.
, motor L12 are respectively driven. In this way, the direction and traveling speed of the electric vehicle are controlled in accordance with the inclination of the joystick lever 1.

In this case, even though the joystick Reno\-1 is in the neutral state, one or both of the variable resistors 54, 55 cannot accurately detect this due to uneven wear of the resistor over time, etc. When a voltage that is somewhat deviated from the current state is output (see Figure 14), if the joystick lever l is in the neutral state, the photointerrupter 2 will detect this, so the output from the photointerrupter 2 above a predetermined level will be variable. It is input to the main controller 5 a little later than the output of the resistors 54 and 55. Therefore, in the main controller 5,
Based on the output of the photointerrupter 2, it is determined that the joystick lever 1 has been operated to stop, and a stop command is output to a braking means (not shown). As a result, the stop command is issued by the main controller 5 when the speed of the electric vehicle is reduced due to the output of the variable resistor 54, 55, so that the electric vehicle can be stopped without much shock.

Here, as shown in FIG. 4, it is also possible to form the area of the end surface of the joystick lever 1 small,
In this case, the neutral region is set to be narrow, as indicated by the symbol N in FIG. In FIG. 5, the symbol W indicates the neutral region in the case of FIG.

According to the embodiment described above, even though the joystick lever 1 is operated to stop and is in the neutral state,
When the output voltage of the variable resistor 54 or 55 deviates from the neutral voltage, the main controller 5
Since the system detects this and issues a stop command, it is possible to effectively avoid the inconvenience of the vehicle not stopping even after a stop operation has been performed. In addition, since neutrality detection by the photointerrupter 2 is performed without contact, it does not have any inconvenient effect on the operation of the joystick lever 1, and has sufficient durability.Furthermore, the shape of the lever tip (
The neutral region can be freely set by changing the end surface area), and the neutral detection signal from the photointerrupter 2 is input to the main control bag W5 later than the neutral detection signal from the variable resistor 54,55. The neutral detection function by the photointerrupter 2 actually functions only in an emergency when the neutral detection by the variable resistor 54, 55 is no longer performed accurately, and there is no discomfort during normal use. There is.

In addition, as shown in FIG. 6, the joystick lever 1
By making the structure slightly movable up and down,
Application to control not only in the horizontal direction but also in the vertical direction is possible. That is, in the figure, when the lever is at position a, no light enters the phototransistor (light receiving element), and when it is at position b, W (normal position), the maximum amount of reflected light is reflected. When it is incident and located at position C, it is possible to obtain a stage in which light is received but at a lower level, so it can also be applied to three-dimensional control.

Further, in the above embodiments, a photointerrupter is used as the proximity switch, but the present invention is not limited to this, and other proximity switches such as a magnetic type and a capacitance type may be used.

It is possible to use various types of proximity switches such as high-frequency oscillation type. For example, when using a magnetic type, the shape of the lever tip may be sharpened to increase directivity, etc., depending on the type. It is desirable to form the shape of the lever tip into a shape.

The present invention can be applied not only to detecting the neutral position of the lever as in the above embodiment, but also to detecting the fully open position by changing the location and height of the photointerrupter.

〔Effect of the invention〕

Since the present invention is configured and functions as described above, according to this, when the joystick lever is operated to stop and the output voltage of the variable resistor deviates from the neutral voltage even though it is in the neutral state, Even if a stop operation is performed, the proximity switch can detect this, and if the main control device issues a stop command based on this detection signal as in the above embodiment, the vehicle will stop even though the stop operation has been performed. The inconvenience of not doing so can be effectively avoided. In addition, since neutrality detection using the proximity switch is performed without contact, it does not have any inconvenient effect on the operation of the joystick lever.
It also has sufficient durability.

Therefore, it is possible to reliably detect the neutral state of the joystick lever, and it does not affect the lever operation in any way. equipment can be provided.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing the configuration of the main parts of an embodiment of the present invention, FIG. 2 is an explanatory diagram showing the specific configuration of the photointerrupter in FIG. 1, and FIG. A block diagram showing the overall circuit configuration, FIG. 4 is an explanatory diagram showing another example of the shape of the tip of the joystick lever, and FIG.
Fig. 6 is an explanatory drawing showing an example of application of the present invention; Fig. 7 is an explanatory drawing showing a conventional joystick controller; Fig. 8 is an explanatory drawing showing a variable resistor. 9 is a diagram showing the voltage output characteristics of the variable resistor, and FIG. 10 is an explanation showing a method of amplifying the output of the variable resistor using a conventional absolute value amplifier. Figure 11 is a diagram showing the output voltage characteristics of Figure 10, Figures 12 to 14 are diagrams explaining the disadvantages when amplifying the output of a variable resistor using an absolute value amplifier. , FIG. 15 is an explanatory diagram showing another conventional example, and FIG. 16 is a diagram showing problems in FIG. 15. DESCRIPTION OF SYMBOLS 1...Joystick lever as an operation lever, 2...Photointerrupter as a proximity switch, 51...First as a first support member
swing arm, 52... second swing arm as a second support member, 53... gimbal mechanism as gimbal-like support means, 54...
First variable resistor, 55... Second variable resistor. 1 No Twisty 7 Cleva 2 Photo Interrupter

Claims (1)

[Claims] (1) The distal end side thereof is supported by a gimbal-shaped support means consisting of a first support member rotatable around a predetermined axis and a second support member rotatable around an axis perpendicular to the one axis. comprising an operating lever, and first and second variable resistors that are respectively installed on the shaft portions of the first and second support members and output voltages proportional to rotation angles of the respective support members; 1. When the second variable resistor simultaneously outputs a predetermined voltage corresponding to the neutral position of each movable range,
In a neutral detection device for a control lever for an electric vehicle having a structure to detect this as a neutral position, a proximity switch capable of detecting the approach of the tip of the control lever in a non-contact manner is arranged in a position corresponding to the neutral position of the control lever. A neutral detection device for an electric vehicle operating lever, which is characterized by being equipped with it.