JPH0449049B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an inclinometer capable of detecting inclination angles in all directions of a structure or a moving object.

Conventional technology There is a demand for constant detection of inclination angles in all directions in industrial robots, ships, civil engineering construction work, special vehicles, etc. In this case, if the maximum inclination angle in all directions is not detected, the detected value is automatically controlled. Very often it is not available otherwise. Some conventional tilt angle measuring devices display the tilt angle in only one axis direction.When measuring the tilt of a certain plane, such devices place the device on the plane and measure 360 degrees around the measurement point. After rotating and setting the angle of elevation or depression to the maximum direction, the angle of inclination shown at that time is read, and the set azimuth angle and the read angle of inclination are combined and used as data.

Problems to be Solved by the Invention As described above, manual work requires measurement time even if it can cover a wide range of azimuth angles, and it is difficult to obtain an accurate omnidirectional tilt at a certain point in time.

Moreover, in recent years, there has been an increasing demand for the use of electrical output as an automatic control signal.

Means and Effects for Solving the Problems The present invention has been made in view of the above points, and its object is to change the inclination of the rotational axis of the rotating body in accordance with the change in the inclination direction of the structure to be measured. The object of the present invention is to provide an omnidirectional inclination angle meter that can calculate the maximum inclination angle in all directions with high precision by detecting the angle and the rotation angle of the rotation axis.

The configuration of the present invention will be explained based on FIG.

A is the structure to be measured.

B is a rotating shaft rotatably supported by the structure A.

C is an inclination angle sensor that detects an inclination angle between a vertical plane and a horizontal plane when the measurement plane is made vertical.

D is a sensor support body that is provided integrally with the rotation axis B and supports the tilt angle sensor C so that the measurement surface of the tilt angle sensor C is always aligned with or parallel to the vertical plane containing the rotation axis B.

E is an angle sensor that detects the relative rotation angle of the rotation axis B with respect to the structure A.

F is a calculation means for calculating the maximum inclination angle θ based on the detection angle α of the inclination angle sensor C and the detection angle β of the angle sensor E.

Since the inclination angle sensor C is supported by the sensor support D and the measurement surface is always held vertically, measurement can be performed in an ideal posture, and high measurement accuracy can be maintained.

In this way, the inclination angle of the rotation axis B can be accurately and simultaneously detected by the inclination angle sensor C and the rotation angle by the angle sensor E, so the maximum inclination angle in all directions can be calculated based on both detection information.

That is, the maximum inclination angle θ in all directions can be calculated from the inclination angle α and rotation angle β of the rotation axis B based on the following equation.

cosθ=(1+tan ² α+cos ² α・sin ² β/1+cos ² α
・sin ² β) ^-1 / ² ...(1) At the same time, the azimuth angle from the reference direction that forms the maximum inclination angle θ (inclination angle azimuth angle) can also be calculated from the following formula.

cos=(1+cot ² α・cos ² α・sin ² β/1−cos ² α
・sin ² β) ^-1 / ² ...(2) The process of deriving the above equations (1) and (2) will be explained based on Figure 2.

In the same figure, it is assumed that a structure A is currently located on an inclined plane having a maximum inclination angle θ at an inclined azimuth angle.

Let S be a plane that includes the rotation axis B and is parallel to the inclined plane,
With any point on the rotation axis B as the reference point O, the same point O
Let h be the horizontal plane passing through.

Furthermore, the axis of rotation B passes through point O on the inclined surface s.
Let N be a straight line perpendicular to .

The tilt angle α detected by the tilt angle sensor C is the rotation axis B.
The angle β detected by the angle sensor E is the angle between the straight line N and the intersection line M between the horizontal plane h and a plane including the point O and perpendicular to the axis of rotation B.

Therefore, if the angle between the straight line N and the horizontal plane h is δ, then the relationship sin δ=cos α·sin β holds true.

Let P be any point on the axis of rotation B that is at a distance r from point O, let P ₁ be the foot of the perpendicular line below point P to the axis of maximum inclination Y passing through point O, and from the same point P ₁ we can draw a horizontal plane h.
The foot of the perpendicular line drawn to is P ₂ , and the horizontal plane h from point P
Let P ₃ be the foot of the perpendicular line drawn to .

Since ∠POP ₃ = α, ∠P ₁ OP ₂ = θ, ∠P ₃ OP ₂ =, P ₁ P ₂ = PP ₃ = rsinα ……(3) From equations (3) and (4), Similarly, finding sin θ for straight line N, we get
This is because α in equation (5) is simply changed to δ and is changed to π/2−. From equations (5) and (6), if we eliminate sinθ and rearrange, we get Since sin δ=cos α·sin β, the above equation (2) can be found from equation (7).

Also, from equation (5) Substituting equation (7) into this equation and rearranging it, we get Since sin δ=cos α·sin β, the above equation (1) can be found from equation (8).

Note that when the tilt angle α and rotation angle β are small values, by replacing tanα≒α, sinβ≒β, cos ² α≒1−α ² and approximating equation (1), the maximum tilt angle θ≒√
α ₂ + β ₂ (θK stated in the originally filed specification = √ ²
+Y ² ).

Embodiment An embodiment of the present invention illustrated in FIGS. 3 and 4 will be described below.

FIG. 3 is a partially cutaway perspective view of the box 1, which is a structure according to this embodiment.

Support plates 2 and 3 are erected at two locations on the left and right sides of the bottom plate of the box 1, and a rotating shaft 6 is rotatably supported by bearings 4 and 5 provided at opposing positions on the support plates. .

An inner box body 7 is suspended between both support plates 2 and 3 by a rotating shaft 6 which passes through and is fixed to the upper plate 7a.

Inside the inner case 7, a support shaft 8 oriented perpendicular to the rotating shaft 6 is rotatably supported by a bearing 9, and a disk 10 is integrally fixed to the support shaft 8. .

The disc 10 is an optical slit disc for an absolute type encoder, and the rotation of the disc 10 is controlled by an optical reader 11 which is provided protruding from the upper plate 7a of the inner case 7 along the radial direction of the disc. Corners can be detected as digital quantities.

A weight 12 is fixed to a predetermined location on the outer peripheral edge of the disc 10.

Further, a disk 13 similar to the disk 10 is fixed to the rotating shaft 6 between the inner case 7 and the support plate 3, and an optical reader 14 is mounted on the case by sandwiching the disk 13 from below. It is installed upright on the bottom plate of 1.

Although not shown, the output wiring from the optical reader 11 is drawn out through the interior of the rotating shaft 6 so as not to affect the rotation of the rotating shaft 6, but it may be routed through a slip ring.

Since the omnidirectional inclination angle meter according to this embodiment has the above-described structure, the rotating shaft 6 is integrated with the disc 13 and is connected to the case 1 so that the inner case 7 is always positioned vertically downward. The disc 10 rotates relative to the inner case 7, and the weight 12 is always positioned vertically below the support shaft 8 inside the inner case 7, which is located vertically below the disk 10 as described above. rotate.

Therefore, when the box 1 is placed on a certain inclined surface with an appropriate inclination azimuth, the rotation angle of the disk 10 read by the optical reader 11 is always equal to the angle α between the rotation axis 6 and the horizontal plane. The rotation angle of the disc 13 read by the optical reader 14 is the relative rotation angle β of the rotation shaft 6 with respect to the box 1 when the rotation shaft 6 maintains the inclination angle α.
will be shown.

A disc 10 rotatably supported within the inner case 7
Since the measurement surface is always held vertically, the inclination angle α can be measured in an ideal posture, and high measurement accuracy can be maintained.

Based on the above-mentioned inclination angle α and rotation angle β that are detected with high precision by the optical readers 11 and 14, the slope on which the box 1 is placed is calculated from the above formulas (1) and (2). The maximum inclination angle θ and the inclination azimuth angle of the box 1 can be calculated.

A block diagram of this arithmetic/display circuit is shown in FIG. 4 and will be explained.

Detection signals from the optical readers 11 and 14 are amplified by amplifier circuits 20 and 21, respectively, and input to an arithmetic circuit 22.

The calculation circuit 22 calculates the equations (1) and (2) above based on the values indicated by both detection signals, and outputs the calculated maximum tilt angle θ to the tilt angle display 23 for display.
The calculated tilt azimuth angle is displayed on the tilt azimuth angle display 24.
output and display it.

As described above, the omnidirectional inclination angle meter according to this embodiment instantly detects the inclination angle α and the rotation angle β of the rotating shaft 6 no matter what posture it is placed in, and determines the maximum inclination angle θ based on these. and tilt azimuth angle can be calculated and displayed.

In fact, it is possible to measure a wide range from 0 degrees to several tens of degrees with an accuracy of less than one-tenth of a degree.

Therefore, by installing this instrument on various types of moving objects, the highly accurate omnidirectional inclination angle of the moving object can be detected in real time and can be applied to various types of control.

When used for a certain automatic control, it is not necessary to obtain the maximum inclination angle θ and inclination azimuth angle in all directions from the detected inclination angle α and rotation angle β of the rotating shaft 6, and the required control amount can be directly calculated from α and β. Of course, you can also ask for .

By filling the inside of the box 1 with a liquid such as silicone, it is possible to have a damping effect on the rotational movement of the inner box 7, and when moving on a highly uneven sloped surface, a damping effect can be provided on the movement of the rotating shaft 6. It is possible to quickly stabilize the detected value by giving the following information, thereby making it easier to read the inclination angle in all directions.

Further, the verticality can be improved by adding a float to the outer peripheral edge of the disk 10 on the side opposite to the weight 12.

Next, another embodiment will be described based on FIG.

The case 1, support plates 2, 3, bearings 4, 5, rotating shaft 6, inner case 7, etc. are the same as in the previous embodiment.

A differential transformer 30 is installed inside the inner case 7 so that the magnetic core 31 slides in a direction parallel to the rotating shaft 6.
is installed on the bottom plate.

The differential transformer 30 used here has a cylindrical shape, and a magnetic core 31 is supported inside so as to be displaceable in the direction of the center axis, and the amount of displacement from the center is detected as an analog amount as a change in voltage. Springs 32 and 33 are inserted on both sides of the magnetic core 31, and the position of the magnetic core 31 changes depending on the degree of inclination of the differential transformer 30.

Since the moving direction of the magnetic core 31 and the rotating shaft 6 are parallel, the inclination angle α of the rotating shaft 6 can be detected as the output voltage of the differential transformer 30.

The rotating shaft 6 passes through the support plate 3 and further protrudes, and a control magnet 34 is fitted to the tip thereof.
A support plate 3 on which a cylindrical magnetoresistive element 35 is installed upright on the bottom plate of the box 1 adjacent to the control magnet 34.
It is fixed at 6.

A control magnet 34 that rotates together with the rotating shaft 6
The resistance value of the magnetoresistive element 35 changes depending on the direction of the magnetic field formed by the magnetoresistive element 35 and the relative angle state of the magnetoresistive element 35 fixed to the box 1. Each relative rotation β of the rotating shaft 6 with respect to the box 1 can be known.

From the tilt angle α and rotation angle β detected by the differential transformer 30 and the magnetoresistive element 35, the maximum tilt angle θ and tilt azimuth angle in all directions can be calculated as in the previous embodiment.

Note that in this embodiment, an azimuth sensor 37 is fixed on the upper plate 1a of the box 1;
7 is designed to detect the angle between the direction of the earth's magnetism and the direction in which the box 1 is oriented, so that the orientation of the box 1 as well as the attitude of the box 1 can be detected.

In addition to the above embodiments, high-accuracy uniaxial tilt angle sensors such as bubble type, capacitive type, and mercury type can be used as a method for determining the tilt angle α of the rotation axis. In addition to the solute encoder magnetoresistive element, synchronizers, potentiometers, etc. can be used.

Ideally, these high-precision uniaxial inclination angle meters should be measured with the measurement surface vertical, and the measurement accuracy deteriorates as the measurement surface becomes more inclined.

In the present invention, since the inclination angle sensor is always held so that the measurement surface is vertical, high measurement accuracy can be maintained, and the maximum inclination angle θ calculated by calculation is also extremely accurate.

Effects of the Invention The present invention can detect the inclination angle and the rotation angle of a rotating shaft within a structure with high precision at all times, and can be used for various purposes.

Furthermore, based on the detected information, the maximum inclination angle θ in all directions in the posture in which the structure is placed can be calculated in real time.

Since the maximum inclination angle θ and the inclination azimuth angle of the state in which the structure is placed can be calculated instantly, various controls of the moving body can be performed in real time.

The structure is capable of being equipped with a conventional high-precision uniaxial tilt angle sensor or angle sensor, so it has excellent measurement accuracy, and the tilt angle sensor is always supported in an ideal posture perpendicular to its measurement surface. Therefore, highly accurate measurement is guaranteed.

The slope angle is 1/10 in a wide range from 0 degrees to several tens of degrees.
Since it is possible to obtain an accuracy of less than a degree, it is possible to provide a highly versatile omnidirectional tilt angle meter with a wide range of applications. It can be similar to a uniaxial tilt angle sensor.

[Brief explanation of the drawing]

Fig. 1 is a diagram corresponding to the claims of the present invention, Fig. 2 is an explanatory diagram for explaining the process of deriving the maximum inclination angle and inclination azimuth angle in all directions, and Fig. 3 is a diagram corresponding to the claims of the present invention. Partially cutaway perspective view of the inclinometer, No. 4
The figure is a block diagram of the calculation/display circuit in the same embodiment, and FIG. 5 is a partially cutaway perspective view of an omnidirectional inclination angle meter according to another embodiment. 1... Box, 2, 3... Support plate, 4, 5... Bearing, 6... Rotating shaft, 7... Inner box, 8... Support shaft,
9... Bearing, 10... Disc, 11... Optical reader,
12... Weight, 13... Disc, 14... Optical reader, 20... Amplification circuit, 21... Amplification circuit, 22
... Arithmetic circuit, 23 ... Tilt angle indicator, 24 ...
Tilt azimuth indicator, 30...Differential transformer, 31
...Magnetic core, 32, 33...Spring, 34...
Control magnet, 35... Magnetoresistive element, 36...
...Support plate, 37...Azimuth angle sensor.

Claims (1)

[Claims] 1. A rotation axis B rotatably supported by the structure A to be measured, an inclination angle sensor C that detects an inclination angle α between the vertical plane and a horizontal plane when the measurement surface is made vertical, and the rotation axis A sensor support D that is provided integrally with the structure A and supports the tilt angle sensor C so that the measurement surface of the tilt angle sensor C is always aligned with or parallel to the vertical plane containing the rotation axis; An angle sensor E that detects a relative rotation angle β of the rotating shaft, and a calculation means F that calculates a maximum inclination angle θ based on a detection angle α of the inclination angle sensor C and a detection angle β of the angle sensor E. Omnidirectional inclination angle meter.