JPH074963A - Angle sensor and inclination detection apparatus - Google Patents

Abstract

PURPOSE:To provide an inclination detection apparatus in which the moving part of an angle sensor can be realized in a simple constitution, which reduces the loss of a bearing, which can be constituted to be small and low cost and which can set a detection angle easily and simply. CONSTITUTION:The detection apparatus is provided with a case 2 into which a liquid 3 is injected and which is constituted so as to be capable of being sealed hermetically, a semiconductor magnetoresistrance element 4 arranged inside the case 2, a magnet 5 which is turned facing the semiconductor magnetoresistance element 4 and a float 7 which is constituted so as to be capable of being turned according to a fluctuation in the liquid level of the liquid 3 inside the case 2. The magnet 5 is installed in the turning central part of the float 7 so as to give turning which corresponds to the inclination of the case 2, and a change in the inclination of the case 2 is detected by a change in the resistance of the semiconductor magnetoresistance element 4 due to the rotation and the movement of the magnet 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an angle sensor and an inclination detecting device which are attached to an object such as various machines and equipment which should not be inclined at a certain angle or more and detect the inclination. It is a thing.

[0002]

2. Description of the Related Art For equipment such as cranes and bulldozers, which are very dangerous to fall over at a certain angle, such as construction machinery such as cranes and bulldozers, the inclination can be detected to obtain a fixed inclination angle. An angle sensor is provided in order to give an alarm when the above is reached.

This type of angle sensor has recently been equipped with a semiconductor magnetoresistive element (hereinafter referred to as an MR element), a magnet which rotates in opposition to the magnetoresistive element, and which changes the resistance value of the MR element in an opposed area, and tilts the magnet. An angle sensor having a pendulum-shaped yoke portion for imparting rotation according to the above, and adapted to detect a tilt change by a resistance change of the MR element has come to be used. This is very convenient for detection and signal processing because a change in the mechanical angle of the magnet due to the yoke can be taken out as an electrical change called the resistance value of the MR element, and has been adopted. .

However, the pendulum-shaped yoke portion is provided with a bearing at its bearing and a weight at its tip so that when the tilt angle of the object to be inspected changes, the sensitivity changes as much as possible. Therefore, when an angle change occurs, the moment of inertia vibrates like a pendulum. For this reason, conventionally, the angle sensor is soaked in oil to suppress the vibration of the yoke due to the viscosity of the oil, and when the angle changes, the yoke is quickly stabilized at a predetermined position. The inclination of the inspection object is detected.

[0005]

However, the conventional angle sensor as described above requires a pendulum-shaped yoke portion and a weight having a length for obtaining a predetermined torque, and a bearing is required in the bearing portion thereof. However, the structure is complicated and expensive. In addition, since the tilt detection device adopts a structure in which the entire angle sensor is immersed in oil, its sealed structure becomes large-scale, and the viscosity of the oil must be controlled. However, it is currently used only for limited mechanical equipment.

In view of the above-mentioned conventional problems, the present invention can realize a movable portion of an angle sensor that moves in accordance with the inclination of an object to be inspected with a simple structure, has a small bearing loss, is small and inexpensive. It is an angle sensor that can be configured, and another object thereof is to provide an inclination detection device that can easily and easily set a detection angle.

[0007]

In order to solve the above-mentioned problems, the angle sensor of the present invention comprises a case constructed so that liquid can be injected and sealed, a semiconductor magnetoresistive element arranged in the case, and A magnet that rotates in opposition to the semiconductor magnetoresistive element, and a float that is configured to be rotatable according to the liquid level change of the liquid in the case are provided, and the magnet is provided at the center of rotation of the float. Rotation corresponding to the inclination of the case is applied, and the inclination change of the case is detected by the resistance change of the semiconductor magnetoresistive element due to the rotation of the magnet.

Further, the inclination detecting device includes a housing for accommodating the angle sensor and attachable to an object to be inspected,
A detection angle setting means for setting a predetermined inclination angle of the object to be inspected; and a detection means for outputting when the detected value by the angle sensor and the set value of the detected angle setting means match. The inclination of the object to be inspected is detected by the output of the detecting means.

Further, a display means for confirming the setting at the time of setting the angle for setting the detection value of the angle sensor by the detection angle setting means is provided so that the setting can be confirmed.

[0010]

According to the present invention, with the above-described structure, the angle sensor is coaxially moved by the float that rotates in response to the change in the liquid level caused by the mechanical change in the object to be inspected. The rotation of the magnet provided at the output causes the resistance change of the semiconductor magnetoresistive element to be output.

Further, when the detected value of the inclination by the angle sensor reaches the set value by the detected angle setting means, the detecting means outputs an output.

Further, when the detection angle is set by the setting means, the setting angle can be easily confirmed by confirming the setting confirmation display means.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the inclination detecting device of the present invention will be described in detail below with reference to FIGS.

In the figure, reference numeral 1 is an angle sensor, and this angle sensor 1 is composed of a case 2 consisting of a main body 2a and a cover 2b, and an appropriate amount of liquid 3 such as oil is contained in the case 2. Just injecting. The case 2 has an MR element 4 serving as a detecting portion of the angle sensor 1.
And a rotatable magnet 5 that changes its resistance value
And a float 7 that is rotatable about a pivot shaft 6 to attach the magnet 5 to give a turning force,
A power supply voltage is supplied to the terminals T1 and T2 of the MR element 4,
A change in resistance value (that is, a change in voltage) corresponding to the inclination of the magnet 5 is obtained at the terminal T3.

The case 2 has a substantially circular front shape and is arranged so that the MR element 4, the magnet 5 and the pivot shaft 6 correspond to each other at substantially the center thereof. The pivot shaft 6 and the case body 2a It is supported by a bearing portion formed on the arm portion 8 provided on the case body 2a. Further, the float 7 to which the magnet 5 is attached is evenly provided on both sides 7a and 7b so as to be rotatable about the axis of the pivot shaft 6, and is stabilized by the buoyancy of the liquid 3. The magnet 5 is attached to the float 7 via a magnetic metal frame 9 for forming a magnetic circuit. Here, the metal frame 9 is integrally formed by insert molding or the like when molding the float 7.
The magnet 5 is attached to the
A protrusion 9a is provided on the outer periphery of the metal frame 9 to prevent the metal frame 9 from coming off.

The liquid 3 is injected about half of the case 2 when both the floats 7a and 7b are opened 180 degrees about the shaft 6. The liquid 3 is injected through the injection port 2c provided on the case cover 2b, and after the injection, the stopper 2 is inserted.
It is designed to be sealed at d. Needless to say, the fitting portion between the case body 2a and the case cover 2b has a hermetically sealed structure so as to prevent liquid leakage.

Further, the MR element 4 is formed on the substrate 4a, and its resistance value changes according to the change of the area where the magnets 5 having a semi-cylindrical shape face each other. The equivalent circuit is shown in FIG. As shown in. In the figure,
A power supply voltage is applied to the terminals T1 and T2, and a resistance change is extracted from the terminal T3.
The MR 5 has the MR 2, and the magnets 5 are evenly opposed to each other when they are horizontal, and the resistance value between the terminals T1 and T3 is equal to the resistance value between the terminals T2 and T3, but the resistance value changes due to the rotation of the magnet 5. Therefore, the change in the resistance value is detected by the terminal T3.
Is taken out as a voltage change. The terminal T
1, T2 and T3 are case main bodies 2a as shown in FIG.
It can be connected to other circuit devices by protruding from the rear surface. A protrusion 2e for positioning when mounting the angle sensor 1 is provided on the rear surface of the case body 2a.

In use of the angle sensor 1 having the above-described structure, the case 2 is placed in a horizontal state (that is, the state of the magnet 5 and the float 7 in which both resistance values of the MR element 4 are equal). In addition, it is attached indirectly or directly to the object to be inspected. Then, the liquid surface of the liquid 3 changes in accordance with the change in the tilt angle, so that the float 7 rotates about the pivot shaft 6 and the magnet 5 also rotates at the same time. By detecting the change in the resistance value of the MR element 4 due to the rotation of the magnet 5 as a voltage change at the terminal T3, the inclination angle of the object to be inspected is detected.

A specific mode of use of the angle sensor 1 having the above configuration will be described below with reference to FIGS.

First, referring to FIG. 3, the angle sensor 1
Is housed in the housing 10, and the printed wiring board 1
1 is attached to the terminal T1, T
2, T3 soldering and positioning of the protrusion 2e. Further, on the printed wiring board 11, in addition to the angle sensor 1, an angle setting variable resistor 12 which is a detection angle setting means, and a setting confirmation LED 13 which also serves as a confirmation display means during inclination detection. And a circuit component 14 that constitutes a detection circuit described later. The base 10a of the housing 10 is attached to the inspection object 15
It can be attached at a predetermined position.

Next, description will be given based on the circuit diagram shown in FIG. Reference numeral 16 is a stabilized power supply circuit, to which a predetermined voltage of a battery or a commercial power supply is appropriately applied. However, if the power supply voltage is unstable, the detection accuracy is adversely affected. It is for keeping the voltage. The output voltage of the stabilized power supply circuit 16 is supplied to the input terminals T1 and T2 of the MR element 4 and also to the angle setting variable resistor 12. Reference numeral 17 denotes a comparator circuit, which is a voltage V of the output terminal T3 of the MR element 4.
1 and the output voltage V2 of the variable resistor 12 for angle setting are compared, and when the output voltage V1 of the MR element 4 becomes large, that is, when the inclination of the object 15 to be inspected becomes larger than a set value, it becomes a detection means. It is a thing. When there is an output from the comparator circuit 17, an output signal is output from the output terminal 19 via the output circuit 18, and is used as an alarm to the operator or a stop signal for mechanical equipment. The output circuit 18
Also, at the same time as the output to the output terminal 19, the LED 13
Can also be turned on, and a confirmation display at the time of tilt detection can be displayed.

Here, the LED 13 can be used as a confirmation display means at the time of inclination detection as described above, but as a setting confirmation display means at the time of setting the detection angle by the angle setting variable resistor 12. Also working. That is, in the state where the housing 10 is tilted according to the allowable tilt angle of the inspection object 15, the angle setting variable resistor 12 is set.
By adjusting the knob 12a of the LED 12 and setting it at the lighting start position of the LED 13, the variable resistor 12 for angle setting is set.
Is to be set. In addition, the variable resistor for angle setting 1
The setting of 2 depends on the mechanical equipment of the inspection object 15,
After attaching the housing 10 to the inspection object 15,
It is also possible to tilt the inspection target object 15 itself and turn on the LED 13 by the same operation as described above to set.

The operation of the tilt detecting device constructed as above will be described below.

First, the object 15 to be inspected is the housing 10.
If the angle setting variable resistor 12 cannot be adjusted after the mounting of the housing 10, the housing 10 is tilted corresponding to the allowable tilt angle of the object 15 to be inspected before the housing 10 is mounted. Then, the angle setting variable resistor 12 is adjusted to set the position where the LED 13 starts to light. In this set state, the voltage V1 output to the output terminal T3 of the MR element 4 outputs a voltage corresponding to the allowable tilt angle, and this voltage becomes the set voltage V2 set by the angle setting variable resistor 12. They are in a matched state, and the adjustment value of the angle setting variable resistor 12 at this time is used as the reference value for detecting the tilt angle of the inspected object 15. After such setting, the housing 10 is attached to the inspection object 1
Attach to 5. Then, when the inspection object 15 is in use, the inspection object 15 is inclined,
Although the liquid surface of the liquid 3 of the angle sensor 1 changes according to the inclination, the float 7 always acts so as to balance on the surface of the liquid 3, and the MR element of the magnet 5 attached to the float 7 The inclination angle with respect to 4 corresponds to the inclination of the inspection object 15. When the inclination becomes equal to or more than the set inclination angle, the detection voltage V1 of the MR element 4 becomes larger than the setting voltage V2 of the angle setting variable resistor 12,
The comparator circuit 17 outputs, and the output circuit 18 outputs an LED.
13 is turned on and a control output is output from the output terminal 19.

Although the comparator circuit 17 is constructed on the assumption that the object to be inspected 15 is inclined to one side, another comparator circuit 17 is provided to detect the inclination in the opposite direction. The output may be generated when the detection output of the MR element 4 becomes smaller than the set value.

[0026]

As described above, according to the present invention, a case configured to be capable of injecting a liquid and hermetically sealed, a semiconductor magnetoresistive element arranged in this case, and a semiconductor magnetoresistive element facing and rotating. And a float configured to be rotatable according to the liquid level fluctuation of the liquid in the case. The magnet is provided at the center of rotation of the float to impart rotation corresponding to the inclination of the case. However, the change in the inclination of the case is detected by the change in the resistance of the semiconductor magnetoresistive element due to the rotation of the magnet, and the weight of the yoke portion does not interfere with the bearing as in the conventional case. The structure is simple, the size can be reduced, and the cost can be reduced. Moreover, since the angle change is detected by the angle change of the float with respect to the change of the liquid surface of the liquid, bearing loss is small and it is easy to follow, and unnecessary vibration such as pendulum-like vibration of the conventional yoke is suppressed. Therefore, the tilt angle can be detected stably.

Further, as the detection device, the detection angle can be set easily and easily, and when setting the detection angle by the setting means, it is possible to easily check the setting confirmation display means. Is what you can do.

[Brief description of drawings]

FIG. 1A is a vertical cross-sectional view of an angle sensor according to a first embodiment of the present invention. (B) is a cross-sectional view of the same.
(C) is a same side sectional view.

FIG. 2 is an explanatory diagram showing a relationship between an equivalent circuit of the MR element and a magnet.

FIG. 3 is a cross-sectional view of a tilt detecting device using the angle sensor of the present invention.

FIG. 4 is a block diagram of an electric circuit of the device.

[Explanation of symbols]

 1 Angle Sensor 2 Case 3 Liquid 4 MR Element 5 Magnet 6 Pivot Shaft 7 Float 10 Housing 12 Angle Setting Variable Resistor (Detection Angle Setting Means) 13 LED (Setting Confirmation Display Means) 15 Inspected Object

Claims (3)

[Claims] 1. A case configured to be capable of injecting a liquid and hermetically sealed, a semiconductor magnetoresistive element arranged in the case, a magnet rotating facing the semiconductor magnetoresistive element, and a case in the case. And a float that is configured to be rotatable about an axis in accordance with fluctuations in the liquid level of the liquid. The magnet is provided at the center of rotation of the float and imparts rotation corresponding to the inclination of the case. An angle sensor configured to detect a tilt change of the case by a resistance change of the semiconductor magnetoresistive element due to rotation of the. 2. A tilt detecting device using the angle sensor according to claim 1, wherein the housing accommodates the angle sensor according to claim 1 and can be attached to an object to be inspected, and the tolerance of the object to be inspected. The detection angle setting means for setting a predetermined inclination angle, and a detection means for outputting when the detected value by the angle sensor and the set value of the detected angle setting means match each other are output. An inclination detecting device, which is configured to detect the inclination of an object to be inspected. 3. A display means for confirming the setting at the time of setting the angle for setting the detection value of the angle sensor by the detection angle setting means, so that the setting can be confirmed.
The tilt detection device described.