JP2913906B2 - Tilt detector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inclination detecting apparatus for detecting an inclination of a member or a structure or the like from a horizontal state by a predetermined angle or more. Such an inclination detecting device is used, for example, when a warning is issued when an aerial work vehicle is inclined by 3 ° or more, or when a construction work vehicle is inclined by 13.5 ° or more.

[0002]

2. Description of the Related Art FIGS. 4 (a) to 6 (b) are known as such conventional tilt detecting devices. 4th (a)
4 (b) is a mercury switch in which mercury 02 and terminals 03 and 04 are sealed in a sealed container 01. This mercury switch is off in the horizontal state shown in FIG. 4 (a), but is turned on when mercury 02 is connected between terminals 03 and 04 in the downwardly inclined state shown in FIG. 4 (b). Therefore, when the camera is inclined leftward and downward by a predetermined angle or more, it can be detected.

The tilt detecting device shown in FIGS. 5 (a) and 5 (b) comprises a reed switch 05, a magnetic fluid 07 sealed in a container 06, and a magnet 08 floating in the magnetic fluid 07. I have. When the member supporting the tilt detecting device is horizontal (see FIG. 5 (a)), the reed switch 05
Is on because magnet 08 is in a close state,
In the inclined state (see FIG. 5 (b)), the reed switch 05 is off because the magnet 08 is at a remote position.

The tilt detecting device shown in FIGS. 6 (a) and 6 (b) is a pendulum 010 which is swingably supported around a rotation axis 09.
The light emitting element 012 and the light receiving element 013 are arranged opposite to each other with a slit 011 having a predetermined shape formed therebetween. In the tilt detecting device shown in FIGS. 6A and 6B, when the pendulum 010 rotates around the rotation axis 09 by a predetermined angle or more, the light receiving element 013 changes to the light emitting element 012.
Light is no longer received. In addition, the applicant filed Japanese Patent Application No. 3-3.
No. 3275 (Japanese Unexamined Patent Publication No. 4-27301),
There has been proposed an inclination detecting device having a structure different from these inclination detecting devices. FIGS. 7 (a) to 7 (d) show this inclination detecting device. The present tilt detection device uses a steel ball 015 magnetized by a permanent magnet 014 as a fulcrum, and joins another steel ball 016 so as to be rotatable around the fulcrum.
17, a Hall element 018 is arranged below.
As shown in FIGS. 7 (a) and 7 (c), when the container 017 is horizontal, the magnetic flux passing through the Hall element 018 is maximum, and the output voltage of the Hall element 018 is maximum. On the other hand, the seventh
(b), 7 (d) As shown in the figure, when the container 017 is tilted by θ, the magnetic flux passing through the Hall element 018 becomes small,
The output voltage of the Hall element 018 decreases. In this manner, the inclination angle θ can be detected based on the magnitude of the output of the Hall element 018.

[0005]

However, the fourth aspect
The inclination detecting device shown in FIGS. 4A and 4B has a large variation in products, and it is difficult to fix the device at a fixed inclination angle (attach it to a vehicle body or the like). In addition, only one direction of inclination can be detected, and there is a possibility of causing pollution by mercury.

Further, in the inclination detecting device using the magnetic fluid shown in FIGS. 5 (a) and 5 (b), the variation of the reed switch product is large, and the hysteresis of the operation timing at which the reed switch is turned on and off is also reduced. large. Therefore, it is difficult to accurately detect a small inclination angle. Also, the temperature characteristics are poor.

The tilt detecting device shown in FIGS. 6 (a) and 6 (b) can detect a tilt angle around a rotation axis supporting the pendulum, but can detect a tilt around an axis perpendicular to the rotation axis. There is a problem that cannot be done.

Furthermore, these tilt detecting devices cannot change the set angle for ON / OFF operation depending on the tilt direction. 7 (a) to 7 (d), since the cross section of the Hall element is circular, the magnetic flux passing through the Hall element is the same no matter which direction the container is tilted by θ. Therefore, the output voltage of the Hall element becomes the same. Therefore, if a certain set voltage is set and the tilt detector is turned on and off by comparing the output voltage of the Hall element, the set angle at which the tilt detector is turned on and off cannot be changed depending on the tilt direction.

The present invention has been made in order to solve these problems. The present invention can detect a tilt angle safely and in any direction with high accuracy, and can detect an inclination angle in accordance with a tilt direction.
It is an object of the present invention to provide a tilt detection device capable of arbitrarily setting a set angle at which N and OFF operations are performed.

[0010]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the inclination detecting device of the present invention has the following configuration. That is, with a support member forming a magnetic pole as a fulcrum, a magnetic pendulum joined rotatably around this fulcrum, a container to which the support member is fixed, and a position fixed to the container and the position of the magnetic pendulum A magnetic sensor that outputs different detection signals and a magnetic control plate that is provided between the magnetic pendulum and the magnetic sensor and that is made of a magnetic material that controls the distribution of magnetic resistance is provided.

[0011]

According to the tilt detecting device of the present invention having the above-described structure,
The container is used by being fixed to a structure such as a vehicle body of a construction vehicle. Since the magnetic pendulum is joined to the support member, it is magnetized to form a fixed magnetic field around it. When the container is held horizontally with the vehicle body and the like, and when the container is inclined with the vehicle body and the like, the magnetic sensor fixed to the container and the magnetic pendulum that always hangs down The relative positional relationship changes, the magnetic flux passing through the magnetic sensor changes, and the detection signal of the magnetic sensor changes. Based on the change in the detection signal, the inclination of the vehicle body or the like to which the container is fixed is detected.

Further, since a magnetic control plate is provided between the magnetic pendulum and the magnetic sensor, the magnetic resistance between the magnetic pendulum and the magnetic sensor can be set arbitrarily. Can be controlled.
Thereby, the inclination angle at which the magnitude of the magnetic flux passing through the magnetic sensor becomes the same can be changed according to the inclination direction.

[0013]

An embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a state in which the inclination detecting device is horizontal,
A permanent magnet 2 and a steel ball 3 are embedded in the collar 1, thereby forming a support member 4. Support member 4
Is fixed to the upper part of the cylindrical container 5. The steel ball 6 is attracted to the steel ball 3 magnetized by the permanent magnet 2 and is joined rotatably around the steel ball 3. A Hall element 7 having a circular cross section is fixed to a lower portion of the container 5, and a magnetic control plate 8 made of a curved key-shaped magnetic material is eccentrically joined to the Hall element 7. Between the magnetic control plate 8 and the steel ball 6, when the steel ball 6 falls due to an impact, the damage of the Hall element 7 and the magnetic control plate 8 is prevented, and at the same time, the steel ball 6 can return to the steel ball 3 immediately. , A non-magnetic guard 9 is provided. In addition, the material of the container 5 is not particularly limited.
And a magnetic path of low magnetic resistance connecting the Hall element 7 to the
Since the magnetic flux passing through the Hall element 7 increases, the detection output of the Hall element can be increased, and the inside of the inclination detector can be shielded from an external magnetic field. In this embodiment, the container 5 is used by fixing it to a vehicle (not shown).

Next, the operation of this embodiment will be described. For convenience of explanation, the direction of the vehicle to which the inclination detecting device is fixed is defined as front, rear, left and right in the direction of the figure. When a vehicle or the like (not shown) inclines, the container 5 inclines, and the steel ball 6 moves smoothly until it comes into contact with the steel ball 3 and stabilizes. Then, since the relative positional relationship between the steel ball 6 and the Hall element 7 changes, the magnitude of the magnetic flux passing through the Hall element 7 changes. Since the output voltage of the Hall element 7 is proportional to the magnitude of the magnetic flux passing through the Hall element 7, the output voltage of the Hall element 7 changes with the change of the inclination angle. In addition, this embodiment is used when tilting at a certain set angle or more.
It is a tilt detector that operates ON, and as a circuit configuration, a comparison circuit that compares the output voltage of the Hall element 7 with a certain set voltage is provided, and when the output voltage of the Hall element 7 becomes smaller than the set voltage, What is necessary is just to comprise so that the output from a comparison circuit may be turned ON.

Next, an operation point at which the inclination detecting device of the present embodiment turns on and off will be described. When the vehicle is horizontal, the axes of the steel balls 3 and 6 and the Hall element 7 are aligned as shown in FIG. 1, and the magnetic flux passes through the magnetic control plate 8 to move the Hall element 7 as shown in FIG. pass. FIG. 2 shows a case where the vehicle is tilted to the right by θ _{1 and} tilted until the axes of the steel balls 3 and 6 coincide with the right end of the magnetic control plate 8. At this time, the magnetic flux passing through the Hall element 7 is shown in FIG.
As shown in FIG. 7, the value is slightly reduced as compared with the case of FIG. At this time, when the output voltage of the Hall element 7 is set to a set voltage, when the vehicle is tilted to the right, the magnetic flux passing through the Hall element 7 is reduced because the magnetic resistance of a part of the magnetic control plate 8 is much smaller than that of the space. Since the output voltage decreases rapidly and the output voltage also decreases, the inclination detector is turned on. On the other hand, when the vehicle is inclined to the left by θ ₂ smaller than θ ₁ as shown in FIG. 3, the output voltage of the Hall element 7 is set to the set voltage because the axes of the steel balls 3 and 6 coincide with the left end of the magnetic control plate 8. Becomes equal to When the vehicle leans further to the left, the lean detector turns ON. Therefore, ON next when the vehicle is tilted the theta ₁ or more when tilted to the right in this embodiment, when tilted to the left is in an ON when tilted _more theta. In this way, the set angle at which the ON / OFF operation is performed can be set by changing the size according to the tilt direction.

In this embodiment, the steel balls 3 and 6
The output voltage of the Hall element 7 when the axis of the ball contacted the left end or the right end of the magnetic control plate 8 was set as the set voltage. This is because the output voltage changes suddenly, and the set voltage may be set arbitrarily. In the present embodiment, the magnetic control plate 8 having a curved key shape is used. However, if a non-circular cross section concentric with the Hall element 7 is used, the set angle for the ON / OFF operation can be set arbitrarily. Conversely, it is also possible to attach a magnetic control plate having a circular cross section to a Hall element having a non-circular cross section so that the set angles are the same for all the inclination directions.

In the above embodiment, the Hall element is used as the magnetic sensor. However, a change in the resistance value may be detected by using a magnetoresistive element. Further, since the steel ball 6 is too sensitive to a minute vibration or the like, if a damper effect is desired, the space in which the steel ball 6 moves may be filled with a fluid such as silicon oil.

Further, in this embodiment, a steel ball is fixed to a permanent magnet as a support member, and a steel ball is used as a magnetic pendulum. However, an electromagnet may be used as a magnet, and the entire support member is formed of a magnet. Is also good. The magnetic pendulum is also rotatable around the support member, and may have any shape as long as magnetic fields having different strengths are formed therearound.

[0019]

The tilt detecting device according to the present invention has the following effects. 1. The magnetic flux passing through the magnetic sensor can be controlled by the magnetic control plate.
The set angle for FF operation can be set arbitrarily. 2. Because of its simple structure, it is easy to produce and inexpensive. 3. Since there is no ON / OFF operation due to contact with a reed switch, etc., the operation is reliable, and there is little aging. 4. One magnetic sensor can detect the inclination in the entire circumferential direction. 5. Since the change in the magnetic field is used for detecting the inclination, there is no risk of pollution and the temperature characteristics are good. 6. Since there is no complicated joining mechanism such as a bearing between the magnetic pendulum and the support member, the magnetic pendulum moves smoothly and there is little hysteresis of ON / OFF operation timing.

[Brief description of the drawings]

FIG. 1 shows one embodiment of a tilt detection device of the present invention, and (a)
3A is a longitudinal sectional view in a horizontal state, FIG. 3B is a sectional view taken along the line AA in FIG. 3A, and FIG. 3C is a view showing a magnetic flux distribution passing through the Hall element in FIG.

FIGS. 2A and 2B show a state in which the inclination detecting device shown in FIG. 1 is inclined rightward by θ ₁ , wherein FIG. 2A is a longitudinal sectional view, and FIG.
7A is a cross-sectional view taken along the line AA, and FIG. 7C is a view showing a magnetic flux distribution passing through the Hall element in FIG.

3 shows a state in which the inclination detecting device shown in FIG. 1 is inclined to the left by θ ₂ , (a) is a longitudinal sectional view, and (b) is (a).
7A is a cross-sectional view taken along the line AA, and FIG. 7C is a view showing a magnetic flux distribution passing through the Hall element in FIG.

4A and 4B show a conventional tilt detecting device using a mercury switch, wherein FIG. 4A is a vertical cross-sectional view in a horizontal state, and FIG. 4B is a vertical cross-sectional view in a tilt state.

5A and 5B show a conventional inclination detecting device using a reed switch and a magnetic fluid, wherein FIG. 5A is a longitudinal sectional view in a horizontal state, and FIG. 5B is a longitudinal sectional view when inclined by θ.

6A and 6B show a conventional tilt detecting device using a pendulum, a light emitting element and a light receiving element, wherein FIG. 6A is a front view and FIG. 6B is a side view.

7A and 7B show a conventional tilt detection device using a magnetic pendulum and a Hall element, and FIG.
(b) is a longitudinal sectional view when inclined by θ, (c) is an AA transverse sectional view in (a), and (d) is an AA transverse sectional view in (b).

[Explanation of symbols]

 2: permanent magnet 3, 6: steel ball 4: support member 7: hall element 8: magnetic control plate

Claims (1)

(57) [Claims] 1. A magnetic pendulum that is rotatably joined around a fulcrum with a support member forming a magnetic pole as a fulcrum, a container to which the support member is fixed, and a magnetic pendulum that is fixed to the container. A magnetic sensor that outputs a detection signal that varies depending on the position of the magnetic sensor, and a magnetic control plate that is provided between the magnetic material pendulum and the magnetic sensor and that is made of a magnetic material for controlling the distribution of magnetic flux density.