JP3590929B2 - Tilt sensor - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to a tilt sensor for detecting a tilt state of a vehicle.
[0002]
[Prior art]
In general, a tilt sensor is used to detect that a two-wheeled vehicle has fallen or that a four-wheeled vehicle has rolled over, and to take various safety measures such as emergency stop of the engine.
[0003]
Conventionally, as a tilt sensor of this type, a reed switch is operated when a balance weight that rotates in accordance with a tilt state of a vehicle rotates more than a predetermined amount to detect a tilt state of the vehicle equal to or more than a predetermined value. Exists. Then, in order to prevent erroneous detection due to instantaneous rotation of the balance weight due to vibration during vehicle running, immerse the balance weight in relatively viscous oil to provide an oil damper function, or The weight is provided with a magnetic damper function for applying a magnetic braking force by a permanent magnet.
[0004]
[Problems to be solved by the invention]
The problem to be solved is that, in the case of the conventional tilt sensor, the case has to be a hermetically sealed structure in which oil is provided in order to have an oil damper function, so that the number of parts and man-hours increase, and the production takes time. . In addition, since the oil damper function is provided, the response time of the detection of the tilting state changes depending on the temperature of the use environment and the oil viscosity. In addition, if the magnetic damper function is provided, it is difficult to adjust the magnetic force due to variations in the magnetic force, and the magnetic flux from the permanent magnet affects the surrounding electric and electronic components, and it is necessary to take magnetic shielding measures. It is becoming.
[0005]
Further, in the conventional tilt sensor, when the vehicle is tilted more than a predetermined amount, it is difficult to adjust the reed switch to be turned on according to the rotating state of the balance weight at that time. That is, there is a tendency that the detection accuracy varies depending on the tilt angle.
[0006]
[Means for Solving the Problems]
The tilt sensor according to the present invention rotates around the center of the circle so that the tilt state of the vehicle can be detected without any complicated adjustment without any damper function. A movement having a shaft and a cutout formed at a predetermined opening angle at an upper portion so as to be symmetrical with respect to a vertical line passing through the center of the circle; When the photo interrupter is turned by more than the predetermined angle, the photo interrupter provided at the position on the vertical line is in a light-blocking state, and the turning by more than the predetermined angle is detected .
[0007]
Then, a detection circuit is configured to output a detection signal when the photo interrupter detects a rotation state of a movement of a predetermined angle or more, and a time constant circuit including a capacitor and a resistor is provided in the detection circuit. By not responding to the instantaneous detection operation of the photointerrupter within the time determined by the time constant, the vehicle is not affected by the running vibration of the vehicle.
[0008]
At that time, particularly in the present invention, when the vehicle passes through a curve or the like, the movement of the movement slowly and largely turns, and the photo interrupter is in the detection state for a time longer than the time determined by the time constant set in the detection circuit. In addition to preventing erroneous detection of a tilted state, it is also possible to reliably detect a state in which the vehicle has fallen by 180 ° and turned upside down. Specifically, the movement has an inverting detection area in the lower central portion where the photointerrupter is detected when the movement is inverted, and the photointerrupters disposed on both sides of the inversion detecting area are forcibly undetected. And a tilt detection area in which the photointerrupter is in a detection state when the left and right sides of the movement arranged in contact with the slit or the window are tilted.
[0009]
【Example】
In the tilt sensor according to the present invention, as shown in FIGS. 1 and 2, a magnetized pendulum type movement 2 is rotatably supported by a rotation shaft 3 in a case 1. ing.
[0010]
The case 1 has a waterproof structure in which the upper portion of the lower case 11 to which the movement 2 is attached is fitted into the upper case 12 via an O-ring 4 for sealing, and the fitted portion is hooked at a plurality of locations. It is formed so that it becomes. In the figure, reference numeral 14 denotes a hook engaging portion.
[0011]
A detection circuit is mounted inside the upper case 12 so that the photo-interrupter 5 detects a rotation state of the movement 2 at a predetermined angle or more and outputs a detection signal when the photo-interrupter 5 is turned on. The mounted circuit board 6 is attached. In the drawing, reference numeral 7 denotes a mounting screw.
[0012]
As shown in FIG. 3, the upper case 12 is integrally formed with a socket portion 8 from which terminals of a power supply Vcc, a ground GND, and a detection output OUT from the circuit board 6 are drawn out.
[0013]
The upper case 12 is provided with a mounting seat 10 for attaching the upper case 12 to the vehicle body via a rubber bush 9 for absorbing vibration.
[0014]
As shown in FIGS. 4 and 5, the movement 2 is provided with a horizontal rotating shaft 3 at the center of the circle. In addition, a notch 21 having a predetermined opening angle α (for example, 70 °) is provided at an upper portion of the movement 2 so as to be symmetrical with respect to a reference position O of rotation which is a perpendicular passing through the center of the circle , At its lower part, a weight portion 22 for balancing the reference position O in the vertical direction is provided.
[0015]
The photo interrupter 5 attached to the circuit board 6 is disposed on a reference position O of the movement 2. When the movement 2 is in the balanced state, the light of the photointerrupter 5 is not interrupted at all by the cutout portion 21 and the output side is switched off, and the movement 2 is turned to the left and right by an angle of more than α / 2. When the light of the photointerrupter 5 moves and is interrupted by the movement 2, the output side is switched on.
[0016]
Thus, the notch 21 is provided in the upper part of the movement 2 and the weight part 22 is provided in the lower part, so that the weight distribution becomes sufficiently heavier in the lower part than in the upper part of the rotating shaft 3, A large moment is required to rotate the movement 2, and the movement 2 becomes difficult to rotate due to vibration during vehicle running.
[0017]
The notch 21 is provided at the upper portion of the movement 2 with a relatively large opening angle α so that the reference position O for the rotation is located at the center. Even if the photo interrupter 5 swings within the range of the opening angle α, the photo interrupter 5 does not respond. Therefore, the photointerrupter 5 is switched on only when the vehicle is tilted by a predetermined angle or more without being erroneously detected due to the vibration during traveling of the vehicle.
[0018]
At this time, in particular, the photo interrupter 5 is turned off by the edge portion of the notch portion 21 of the movement 2, so that the left and right set angles α / 2 or more around the reference position O of the vehicle are tilted. Since the detection is performed, the tilt state detection can be easily and accurately performed.
[0019]
FIG. 7 shows an example of a detection circuit for detecting the tilting state of the vehicle according to the switching state on the output side of the photo interrupter 5.
[0020]
Here, a circuit is configured to output a high-level detection signal when the photointerrupter 5 detects a rotation state of the movement 2 at a predetermined angle or more and enters a switch-on state. A time constant circuit composed of capacitors C1 and C2 and a resistor R4 is provided therein so as not to respond to an instantaneous switch-on of the photointerrupter 5 within a time determined by the time constant.
[0021]
That is, when the photointerrupter 5 is in a normal state in which the photointerrupter 5 is in a switch-off state, that is, when the output signal DS of the photointerrupter IC 5 'shown in FIG. 7 is at a high level, the capacitors C1 and C2 are in a charged state and the output transistor Q4 is turned on, and the voltage of the output terminal OUT is at the low level. Then, when the vehicle is tilted and the photo-interrupter 5 is turned on (the output signal DS of the photo-interrupter IC 5 'shown in FIG. 7 is turned to a low level), a discharge circuit for the capacitors C1 and C2 is formed, and After the time, the output transistor Q4 is turned off, and the voltage at the output terminal OUT switches to the high level.
[0022]
Therefore, when the movement 2 is momentarily rotated by a predetermined angle or more due to the running vibration of the vehicle, erroneous detection of the tilted state is not performed.
[0023]
In addition, the detection circuit is configured to continuously perform safety measures such as fuel cut-off and power cutoff of the engine ignition system even in the case where the two-wheeled vehicle comes up to a normal state after tilting. In order to achieve this, a holding circuit for detecting the tilting state is provided which includes resistors R5 and R6, a capacitor C3 and a transistor Q1.
[0024]
That is, in the holding circuit, when the tilting state of the vehicle is detected and the output transistor Q4 is turned off and the voltage of the output terminal OUT becomes high level, the transistor Q1 is turned on, whereby the output transistor Q4 is turned off. Is held. This holding state is released by turning off the ignition switch of the vehicle and cutting off the power.
[0025]
Further, this detection circuit is provided with a constant current circuit that supplies a constant current to the collector of the control transistor Q2, and the voltage of the battery power supply (Vcc) changes due to a change in the specification of the rating, the state of charge, the temperature environment, and the like. Therefore, the timing of the tilt state detection is not changed.
[0026]
Here, a zener diode ZD is provided as a constant current circuit to make the battery power supply (Vcc) constant, so that a constant current collector current is always supplied through the resistor R7 when the control transistor Q2 is turned on. .
[0027]
That is, when the constant current circuit including the zener diode ZD and the resistor R7 is not provided, when the voltage of the battery power supply (Vcc) fluctuates, the collector current of the control transistor Q2 changes accordingly and the switching timing changes. As a result, the tilt state detection timing determined by the capacitors C1 and C2 and the resistor R4 fluctuates.
[0028]
In the tilt sensor configured as described above, for example, when the movement 2 rotates slowly and largely when the vehicle travels on a curve, the photointerrupter 5 is switched over for a time set in the time constant circuit. When turned on, erroneous detection of the tilted state is performed.
[0029]
In such a case, particularly in the present invention, when the vehicle is traveling on a curve or the like, the movement 2 rotates slowly and largely, and the photo-interrupter 5 is turned on for a time longer than the time determined by the time constant set in the detection circuit. In order to prevent the erroneous detection of the tilted state from being performed, and to be able to reliably detect the state in which the vehicle has fallen by 180 ° and turned upside down, the movement 2 is The configuration is as shown in FIG.
[0030]
That is, its movement 2, forcing an inverted detection area A1 of the photo-interrupter 5 is detected state of the switch turned on when the inverted in the lower central portion thereof, a photointerrupter 5 arranged on both sides of the inverted detection area A1 Slits S1 and S2 for making the switch-off non-detection state, and tilt detection in which the photo-interrupter 5 is in the switch-on detection state when the movement 2 disposed in contact with the slits S1 and S2 is tilted to the left or right. Areas A2 and A3 are provided.
[0031]
Therefore, the slits S1 and S2 for forcibly turning off the photo interrupter 5 are arranged in the middle of the movement 2, and the tilt detection areas A2 and A3 where the photo interrupter 5 is turned on are divided outside each of them. The photointerrupter 5 is not switched on for longer than the time set in the time constant circuit even if the movement 2 is largely turned, for example, when the vehicle is traveling on a curve, and the tilt state is erroneously detected. Is not done.
[0032]
At this time, the photo interrupter 5 is forcibly turned off by the slits S1 and S2, whereby the set time in the time constant circuit is reset to the initial state.
[0033]
Also, when the vehicle is turned over by 180 ° to be in an inverted state, the inverted detection area A1 arranged at the intermediate position of the rotation of the movement 2 is switched on by facing the photointerrupter 5, thereby The inverted state will be detected.
[0034]
In addition, instead of the slits S1 and S2, as shown in FIG. 6, windows W1 and W2 for turning on the photointerrupter 5 in the light passing state may be provided.
[0035]
【The invention's effect】
As described above, in the tilt sensor according to the present invention, the pendulum-type movement is rotatably supported on the case, and the fact that the movement has rotated by a predetermined angle or more is detected by the photo interrupter. Thus, it is possible to detect the tilting state of the vehicle with high responsiveness and high accuracy without performing complicated adjustment.
[0036]
According to the present invention, when the movement is rotated by a predetermined angle or more and the detection output of the photo-interrupter is continued for a time determined by a predetermined time constant or more, a tilt-state detection signal is output. Since the detection circuit is provided, it does not respond to the instantaneous detection output of the photointerrupter within the time determined by the time constant, and is not affected by the running vibration of the vehicle.
[0037]
In this case, particularly according to the present invention, the tilt detection area is divided by providing a slit or a window for forcibly making the photo-interrupter in the non-detection state in the middle of the movement, so that the vehicle can be used when traveling on a curve. For example, even if the movement rotates slowly and largely, the photointerrupter does not enter the detection state for a time longer than the time determined by the time constant, thereby preventing erroneous detection of the tilt state. Also, when dividing the tilt detection area, the inverted detection area is arranged in the lower central part of the movement, so that even when the vehicle falls down by 180 ° and becomes inverted, It has the advantage that it can be detected.
[Brief description of the drawings]
FIG. 1 is a front view showing an embodiment of a tilt sensor according to the present invention.
FIG. 2 is a side sectional view of the tilt sensor in the embodiment.
FIG. 3 is a bottom view of a socket terminal portion of the tilt sensor according to the embodiment.
FIG. 4 is a front view showing a movement of the tilt sensor in the embodiment.
FIG. 5 is a side view of the movement.
FIG. 6 is a front view showing another configuration example of the movement.
FIG. 7 is an electric circuit diagram showing a detection circuit for detecting a tilting state of the vehicle.
[Explanation of symbols]
Reference Signs List 1 case 11 lower case 12 upper case 2 movement 3 axis 5 photo interrupter A1 inverted detection area A2 tilt detection area A3 tilt detection area S1 slit S2 slit W1 window W2 window

Claims (1)

It has a pivot axis at the center of the circle, and a notch is formed in the upper part at a predetermined opening angle so as to be symmetrical with respect to a vertical line passing through the center of the circle, and is rotatably supported by the case. A movement, a photointerrupter provided at a position on the perpendicular line for detecting that the movement has rotated more than a predetermined angle, and a detection output of the photointerrupter continuing for a time set by a predetermined time constant or more. A detection circuit configured to output a detection signal of a tilted state when the photodetector is tilted, and an inverted detection area in which a photointerrupter is detected when the movement is inverted, and an inverted detection area in the lower central portion of the movement. A slit or window that forcibly disables the photointerrupters located on both sides of the Tilting sensor which left respectively arranged the movement, the photo-interrupter when the right side of tilting, characterized in that a and tilt detection area to be detected state by.

Images