JPH08184434A - Fixing device for inclination sensor - Google Patents

Abstract

PURPOSE: To obtain a compact device for fixing an inclination sensor which is stabilized against vibration and temperature variation and the attitude thereof is adjustable. CONSTITUTION: In the device for building an inclination sensor, detecting inclination of a machine against the direction of gravity, in the machine body and fixing the inclination sensor in place, inclination sensors 4, 7, 10 are held on the surface and a board 1 is provided on the read side oppositely to a fixing base 11 disposed on the vertical wall face of the machine body. A supporting leg 15 having adjustable length is provided in order to support the board 1 on the fixing base 11 swingingly about the axis connecting a pair of contact members 14a, 14b provided, while being spaced apart in the horizontal direction and touching the fixing base 11, on the rear surface of the board 1 thus supporting the board 1 on the fixing base 11 at a position separated from the swinging axis by a predetermined distance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tilt angle sensor incorporated in a device body such as a surveying instrument and detecting the tilt of the device with respect to the direction of gravity.

[0002]

2. Description of the Related Art As an inclination angle sensor of this type, there is known an orthogonal two-direction sensor which detects an inclination angle around two horizontal axes which are orthogonal to each other by utilizing reflection on a free liquid surface. For example, in Japanese Patent Laid-Open No. 58-99712, there are two orthogonal
Two beams extending in each direction are emitted toward the free liquid surface, and both beams passing through the free liquid surface are projected on the line sensor. From the output of the line sensor, the inclination angle around the X axis and the Y axis around A tilt angle sensor for detecting the tilt angle and the tilt angle are disclosed. Many tilt angle sensors using a two-dimensional light receiving element instead of the line sensor are also known.

In such an inclination angle sensor, when the main body of the device is installed correctly vertically with respect to the direction of gravity, the intermediate position between the two beams should match the reference position (for example, the zero point) of the line sensor. In addition, it is usually mounted in the correct posture with respect to the device body. And
An angle calculation circuit such as a microcomputer is provided for converting the inclination angle of the device body with respect to the gravity direction from the amount of deviation from the reference position. However, since the reference position of the line sensor can be easily calibrated (calibrated) by a microcomputer or the like to some extent, there is no problem even if there is some error in the mounting attitude of the tilt angle sensor.

However, no matter how much the reference position can be calibrated, there is an allowable error range in the mounting attitude of the tilt angle sensor. For example, in the one disclosed in the above-mentioned publication, since the length of the line sensor is limited, if the intermediate position of the two beams is set to a position deviating from the reference position of the line sensor, the tilt angle The detectable area is reduced accordingly. In particular, a highly sensitive tilt angle sensor is indispensable for high-accuracy surveying, and in order to improve detection sensitivity, the amount of beam movement relative to the amount of tilt of the main body of the device is expanded so that even a slight tilt causes a large beam movement. Need to be configured. Therefore, it is preferable that the reference position of the line sensor is set to the center of the line sensor as much as possible. Further, it is preferable that the reference position of the two-dimensional light receiving element is set to the center of the element as much as possible.

In order to attach the tilt angle sensor to the posture within the allowable error range, an adjusting mechanism capable of adjusting the posture after being incorporated in the main body of the equipment is required. As a conventional method for attaching the tilt angle sensor to the main body of the apparatus in an adjustable manner, the method illustrated in FIGS. 3 and 4 is generally used. FIG.
4 and FIG. 4 show a partial plan view of the plane in which the Z direction is the direction of gravity, and in FIG.
01, and the substrate 101 is fixed to the vertical wall surface 102 of the device body with the screw 103. The contact surface between the substrate 101 and the vertical wall surface 102 is parallel to the YZ plane, and therefore, if the screw 103 is loosened, the tilt adjustment within that surface (the tilt adjustment about the X axis) is possible. Further, in the case of FIG. 4, the inclination angle sensor 100 is fixed to the L-shaped mounting substrate 104,
The vertical wall surface 1 of the device body is fixed to the board 104 by the screws 105.
Fixed to 02. Also in this case, if the screw 105 is loosened, Y-
It is possible to adjust the tilt (adjust the tilt around the X axis) within a contact plane parallel to the Z plane.

In any of the above examples, when adjustment in two directions is required, it is necessary to provide a contact surface parallel to each direction and adjust the inclination within each surface.

[0007]

In such a conventional general mounting method, since the contact surface itself for adjusting the tilt is a surface for supporting the tilt angle sensor, only the weight of the tilt angle sensor can be supported. A large enough area was needed.
Particularly in the case of FIG. 3, when the area of the contact surface is increased, the distance between the inclination angle sensor 101 and the vertical wall surface 102 increases,
It becomes large in the Y direction as a whole. Although the one shown in FIG. 4 is compact in the Y direction, the center of gravity of the tilt angle sensor is separated from the fixed point, so that it has another problem that the strength against vibration is poor and mechanical displacement occurs. Further, when the temperature of an L-shaped member as shown in FIG. 4 is changed, thermal deformation often occurs, and as a result, the inclination angle sensor becomes unstable with respect to the temperature change, which is difficult as in a surveying instrument. It was not suitable for equipment that is frequently used in the environment.

Therefore, it is an object of the present invention to provide a mounting device for a tilt angle sensor which is compact and stable against vibrations and temperature changes and whose posture can be adjusted.

[0009]

According to the present invention, there is provided a mounting device for mounting and fixing an inclination angle sensor for detecting an inclination of an apparatus with respect to a gravity direction in the apparatus body, wherein the inclination angle sensors 4, 7 are provided on the surface. , Hold 10,
The back side is a mounting base 11 on the vertical wall of the device body.
And the mounting base 11 is provided.
The pair of contact members 14a and 14b that come into contact with
By arranging them at positions separated from each other on the back surface in the horizontal direction, the substrate 1 is supported on the mounting base 11 so as to be swingable around a swing axis connecting the pair of contact members 14a and 14b, and the swing axis is There is provided a mounting device for an inclination angle sensor, characterized in that a support leg 15 having a length adjustable for supporting the substrate 1 is provided on the mounting base 11 at a position separated by a predetermined distance from.

The inclination angle sensor mounting device of the present invention further directs the substrate 1 toward the mounting base 11 at a substantially center of gravity of a triangle formed by the pair of contact members 14a and 14b and the support leg 15. It is possible to provide an elastic member 17 that presses by pressing. Further, the support leg 15 can be provided at a position of an apex of the isosceles triangle whose base is the swing axis, the top facing the base.

[0011]

According to the tilt angle sensor mounting apparatus of the present invention, the substrate 1 is supported at three points by the pair of contact members 14a and 14b and the supporting leg 15, and the length of the supporting leg 15 is adjusted to adjust the substrate 1.
Is swung around a swing axis connecting the contact members 14a and 14b to adjust the attitude of the tilt angle sensor.

By providing the elastic member 17 at the center of gravity connecting the three points, a uniform load is applied to the three points, and the substrate 1 is constantly and stably pressed toward the mounting base 11.

[0013]

Embodiments of the present invention will be described below. 1 is a plan view of a tilt angle sensor mounting device according to an embodiment of the present invention, and FIG. 2 is a sectional view taken along line II-II of FIG. As shown in FIG. 1, a light projecting section 4, a liquid level reflector 7, and a light receiving section 10 which constitute an inclination angle sensor are fixed to the surface of a rectangular substrate 1, respectively. The light projecting unit 4 includes a light source 2 such as a semiconductor laser and a collimator lens 3. The liquid level reflector 7 is composed of a viscous liquid 5 such as silicon oil enclosed in a container having a transparent bottom and a right-angle prism 6 provided at the bottom of the container. The light receiving section 10 is composed of a condenser lens 8 and a two-dimensional light receiving element 9 such as a two-dimensional CCD. Each of the optical elements of the light projecting unit 4 and the light receiving unit 10 is housed in a cylindrical light-shielding container.

The light from the light source 2 is made into a substantially parallel light flux by the collimator lens 3 and enters from one surface of the rectangular prism 6. The incident light is reflected by the free liquid surface of the liquid 5 and exits from the other inclined surface of the right-angle prism 6, and the condenser lens 8
Is focused on the two-dimensional light receiving element 9. Therefore, when the substrate 1 is inclined with respect to the free liquid surface of the liquid 5, the focus position of the laser light on the two-dimensional light receiving element 9 moves. For example, when the substrate is tilted around the Y axis (θx direction) in FIG. 1, the laser beam focusing position is indicated by arrow A on the two-dimensional light receiving element 9.
When the substrate tilts around the X axis (θy direction), the focus position of the laser light moves in the direction perpendicular to the arrow A direction. Therefore, the inclination angle of the substrate 1 about the XY axes can be known from the output of the two-dimensional light receiving element 9.

On the vertical wall surface 12 of the device body, a rectangular mounting base 11 which is slightly larger than the substrate 1 is attached with screws 13
It is fixed by a, 13b and 13c. A predetermined gap is provided between the substrate 1 and the mounting base 11, and a pair of contact members 14a and 14b made of steel balls are provided between the two.
A support leg 15 made of a rounded screw is provided. The pair of contact members 14a and 14b are fitted in grooves having a V-shaped cross section provided in both the substrate 1 and the mounting base 11. The support leg 15 is screwed into a screw hole penetrating the board 1, and its tip projects from the back surface of the board and contacts the surface of the mounting base 11.

The positions of the pair of contact members 14a and 14b are
The support leg 15 is provided above the substrate 1 at a position where a straight line connecting the centers of the substrates 1 is horizontal, and the support leg 15 is provided at a substantially central position below the substrate 1. Therefore, the pair of contact members 14a, 14b and the support leg 15 are located at positions substantially corresponding to the respective vertices of the isosceles triangle drawn on the back surface of the substrate 1, and when the screws forming the support leg 15 are turned, Reference numeral 1 swings about the X axis (in the θy direction) around the swing axis connecting the contact members 14a and 14b, that is, the base of the isosceles triangle.

At the position corresponding to the center of gravity of the above-mentioned isosceles triangle on the back surface of the substrate 1, a retaining portion 16 for connecting the substrate and the mounting base 11 is provided. Retaining part 16
A leaf spring 17 is inserted between the mounting base 11 and
The substrate 1 is constantly pressed in the Y direction. Next, a method of adjustment by the tilt angle sensor mounting device in this embodiment will be described. First, when the tilt angle sensor is mounted on the vertical wall surface of the device body as shown in the figure, the light source 2 is turned on, the position of the condensing point on the two-dimensional light receiving element 9 is determined based on the output, and the tilt angle sensor It is determined whether or not the posture is attached within the allowable error range. If it is outside the allowable error range around the Y axis (θx direction), screw 13
It suffices to loosen a, 13b and 13c and rotate the mounting base around the Y axis while watching the output of the two-dimensional light receiving element 9. When it is out of the allowable error range about the X axis (in the θy direction), the screw forming the support leg 15 is turned while observing the output of the two-dimensional light receiving element 9, and the substrate 1 is swung about the swing axis. . In this way, the tilt angle sensor is attached to the posture within the allowable error range.

[0018]

According to the present invention, since the inclination angle sensor is mounted on the mounting base of the device body by the most stable method of supporting three points, the influence of vibration or temperature change externally applied to the device body. Is extremely small. At the center of gravity of three-point support, a structure with excellent vibration resistance is obtained by constantly imparting a pressing force to the substrate side of the device body. The three-point support position corresponds to each vertex of the isosceles triangle. By doing so, it becomes a more stable structure.

Further, in the embodiment of the present invention, the adjustment 4
Since all the screws 13a, 13b, 13c, 15 are oriented in the same direction, the insertion direction of the screwdriver at the time of adjustment is the same, which leads to a reduction in adjustment man-hours.

[Brief description of drawings]

 4. Brief description of the drawings

FIG. 1 is a plan view of a tilt angle sensor mounting device according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line II-II of FIG.

FIG. 3 is a plan partial cross-sectional view showing an example of a conventional method for adjustably mounting the tilt angle sensor on the device body.

FIG. 4 is a plan partial cross-sectional view showing another example of a conventional method for adjustably attaching the tilt angle sensor to the device body.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 4 Light emitting part 7 Liquid level reflector 10 Light receiving part 11 Mounting base 12 Vertical wall surface 14a, 14b of device body Pair of contact members 15 Support legs 16 Fall prevention part 17 Leaf spring

Claims (3)

[Claims] 1. A mounting device for mounting and fixing a tilt angle sensor for detecting a tilt of a device with respect to a gravity direction in a device body, wherein the tilt angle sensor is held on a front surface and a back surface is on a vertical wall surface of the device body. By providing a substrate arranged to face the mounting base, and by providing a pair of contact members in contact with the mounting base at positions horizontally separated on the back surface of the substrate,
The substrate is supported on the mounting base so as to be swingable about a swing axis connecting the pair of contact members, and the substrate is supported on the mounting base at a position separated from the swing shaft by a predetermined distance. A device for mounting a tilt angle sensor, which is provided with adjustable support legs. 2. The elastic member for pressing the substrate toward the mounting base at a substantially center of gravity of a triangle formed by the pair of contact members and the support leg is provided. Mounting device for tilt angle sensor. 3. The mounting of the tilt angle sensor according to claim 1, wherein the support leg is provided at a position of an apex facing the base of an isosceles triangle whose base is the swing shaft. apparatus.