JPH0528924U - Structure level measuring device - Google Patents

Abstract

(57) [Summary] [Purpose] To realize a high-precision electronic level measuring device with an inexpensive configuration. [Structure] A light receiver 2 which is installed at a measurement point of a structure and outputs a light reception signal by receiving a laser beam, a laser irradiator 1 which horizontally irradiates a laser beam and horizontally turns at a predetermined speed, and a laser. It comprises an elevating device 15 for moving the irradiator 1 up and down at a predetermined speed, and means 19 for detecting a change in the emission level of the laser irradiator 1 for each predetermined increment / decrement unit. Based on the change in the laser emission level detected by the detection means 19 within the light receiving period of the laser beam by the light receiver 2 and the number of times the light reception signal is output at each of these levels, the level of the measurement point at which the operation means 20 installs the light receiver 2 Is calculated.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an improvement of a measuring device for measuring the level of a large number of points of a structure using a laser beam.

[0002]

[Prior Art]

 As a method of knowing the level changes at a large number of measurement points set on a structure, such as measurement of uneven settlement of a structure, many electronic measurement methods have recently been adopted in which measurement is performed using a laser beam emitter and receiver. ing.

For example, in Japanese Patent Laid-Open No. 60-25413, a light receiving device is provided in which a light emitting device for a laser beam is set at a reference point, a light receiving device is attached to a measurement site, and a large number of light receiving elements are arranged vertically. It has been proposed to irradiate a laser beam on a container to judge the level of the measurement site from the position of the received element. When there are many measurement points such as uneven settlement of the structure and periodic measurement is required, set the photoreceiver at that position and input its output to the computer to improve efficiency. A good measurement of

[0004]

[Challenges for devising]

 However, in this case, in order to increase the level accuracy (resolution), it is necessary to increase the array density of the light-receiving elements that are arranged in the upper and lower sides of the light receiver. However, when there are many measurement points, the light receiver must be installed. Due to the increase in the number of devices, the need to prepare a large number of photo detectors with such a high element density makes the measurement system very expensive.

The present invention has been made to solve the above problems, and an object thereof is to realize a highly accurate electronic level measuring device with a cheaper configuration.

[0006]

[Means for achieving the object]

 The present invention is a receiver that is installed at a measurement point of a structure and outputs a light reception signal by receiving a laser beam, a laser irradiator that horizontally irradiates a laser beam and horizontally turns at a predetermined speed, and this laser. An elevating device for moving the irradiator up and down at a predetermined speed, and means for detecting a change in the emission level of the laser irradiator for each predetermined increment / decrement unit are provided. Means for calculating the level of the measurement point where the photodetector is installed is provided from the change in the laser emission level detected by the detection means and the number of times the photodetection signal is output at each of these levels.

[0007]

[Action]

 The calculation means divides the sum of the product of the light emission levels of the laser beam and the number of light receptions of the light receiver at that level by the total number of light receptions, so that the measurement variations caused by the width of the laser beam are averaged, and high accuracy is obtained. Level can be measured.

[0008]

【Example】

 1 to 3 show an embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes a laser irradiator for irradiating a laser beam, and a large number of light receivers 2 for receiving the laser beam are arranged at respective measuring points around the laser irradiator 1.

The light receiver 2 includes a single light receiving element that outputs an electric signal by receiving a laser beam. For example, a phototransistor or a photodiode is used for this light receiving element.

The laser irradiator 1 is supported by an elevating device 15 and horizontally oscillates at a predetermined speed while emitting a laser beam in a horizontal direction.

To this end, the laser irradiator 1 includes a turning motor that rotates at a predetermined constant speed. In addition, the leveling device 4 is provided between the elevating device 15. The horizontal adjustment device 4 includes a motor that rotates the laser irradiator 1 about each of the horizontal rotation axes that intersect directly with each other, and an inclination sensor that detects the inclination angle of the laser irradiator 1 about each axis. The laser irradiator 1 is kept horizontal by driving each motor based on the detection angle of the sensor.

The elevating device 15 is composed of, for example, a screw mechanism fed by the rotation of a motor, and expands and contracts at a predetermined constant speed. The elevating device 15 may be composed of a hydraulic cylinder or the like.

A vertical position detector 19 is provided in parallel with the lifting device 15. Each time the light emission level of the laser irradiator 1 changes by a predetermined measurement unit Δh, the vertical position detector 19 detects the level and outputs it to the control device 20 as a height signal.

The control device 20 drives the motor based on the tilt signal output from the tilt sensor to keep the laser irradiator 1 horizontal. In addition, the control device 20 serves as a calculation means to determine the light receiver 2 from the laser light emission levels detected by the vertical position detector 19 within the light receiving period of the laser beam by the light receiver 2 and the number of times the light reception signal is output at each of these levels. Calculate the level of the installed measurement point. That is, the product of the laser emission level and the number of times the received light signal is output at that level is summed for each level, and this is divided by the total number of output of the received light signal to calculate the level at the measurement point.

Next, the operation will be described.

The laser irradiator 1 supported by the elevating device 15 rises from a lowest position, for example, at a predetermined speed and emits a laser beam in a horizontal direction while turning at a predetermined speed.

When this laser beam enters the light receiver 2, the light receiver 2 outputs a light reception signal to the control device 20.

By the way, since the laser beam emitted from the laser irradiator 1 is a parallel laser beam having a circular cross section, the center of the laser beam of the light receiver 2 falls within the range of height ha ± α as shown in FIG. And receives a laser beam and outputs a light reception signal.

As a result, while the laser beam is in this height range, the light receiver 2 inputs a light reception signal to the control device 20 at a constant interval according to the turning speed of the laser irradiator 1.

Further, every time the laser emission level of the laser irradiator 1 increases by Δh, a height signal indicating a new laser emission level is input from the vertical position detector 19 to the control device 20.

That is, the laser emission level detected by the vertical position detector 19 slightly changes even within the output range of the light receiving signal, so that the level of the light receiving device 2 can be accurately determined with only one high value signal. It is not possible.

Therefore, the control device 20 calculates the level of the photodetector 2 by the following method based on these input signals.

That is, the control device 20 firstly outputs the pulse number n of the light receiving signal input from the same light receiving device 2 at each laser light emitting level different by the unit height Δh shown in FIG.₁, N₂, N ₃ ,. ． ． , N_nTo count.

Next, the control unit 20 controls the center values h ₁ , h ₂ , h ₃ ,. ． ． Find h _n .

Then, based on these values, the following calculation is performed to obtain the level of the light receiver 2. The same applies when the level is measured while the laser irradiator 1 is lowered.

[Equation 1] By the above calculation, the influence of the variation in the detection height based on the width of the parallel laser beam is eliminated, and the accurate level ha of the light receiver 2 is obtained. By this method, it is possible to eliminate the influence of the error due to the vertical deflection of the laser beam caused by the mechanism of the laser irradiator 1 and the lifting device 15. In this way, the level can be accurately measured for all the photodetectors 2 to be measured. Since the light receiver 2 only needs to have one light receiving element, the manufacturing cost is low, and the larger the number of measurement points where the light receiver 2 is arranged, the smaller the measurement cost per measurement point.

[Effect of the device]

 As described above, the level measuring device of the present invention sums up the product of the number of times the light receiving signal is output at each laser emission level during the laser receiving period and the height of that level for each level, and outputs the product of the light receiving signal. By dividing by the total number, the level at the measuring point where the photoreceiver is installed is calculated, so the adverse effects of the width of the laser beam and the vertical fluctuation of the laser beam on the measurement can be eliminated, and highly accurate level measurement can be performed. It can be carried out. Further, since each light receiver needs to have only one light receiving element, it is possible to perform level measurement at many measurement points at low cost.

[Brief description of drawings]

FIG. 1 is a front view of a level measuring device showing an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a light receiving range of a light receiver.

FIG. 3 is a graph showing a relationship between a light receiving signal pulse and a height signal.

[Explanation of symbols]

 1 Laser Irradiator 2 Light Receiver 15 Lifting Device 19 Vertical Position Detector 20 Control Device

Claims (1)

[Scope of utility model registration request] 1. A light receiver which is installed at a measuring point of a structure and outputs a light reception signal by receiving a laser beam, a laser irradiator which horizontally irradiates a laser beam and horizontally turns at a predetermined speed, An elevating device for moving the laser irradiator up and down at a predetermined speed, and means for detecting a change in the emission level of the laser irradiator for each predetermined increment / decrement unit are provided, while the detection is performed within the light receiving period of the laser beam by the light receiver. A structure level measuring device comprising means for calculating the level of a measurement point at which a photodetector is installed, based on changes in the laser emission level detected by the means and the number of times the photodetection signal is output at each of these levels. .