JPH02236109A - Laser house for detector of plane position - Google Patents

Abstract

PURPOSE:To project laser light in a horizontal direction at all times even when a laser house is inclined on the weak fragile ground, etc. by suspending a source of said laser light by a hanging string below a rotary base. CONSTITUTION:A laser house for use in triangulation has a pentagonal prism 4 provided at the center of a rotary base 3. A compound prism 5 and a double- face reflecting mirror 6 are also provided respectively at the outer side and above the prism 4. A laser light from a light source 8 is divided into two by the compound prism 5, and the laser lights rotating in an opposite direction each other are projected. In this case, the laser source 8 is suspended by a string 10 below the rotary base 3. Therefore, even if the laser house is inclined due to the inclination of the ground, the laser light is incident upon the reflecting mirror 6 in a vertical direction, and the projected laser lights are always kept horizontal, whereby such inconveniences as re-adjustment, re- collimation and the like are removed.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention irradiates a rotating laser beam onto a photodetection sensor placed at a measurement point and detects the triangular i1? The present invention relates to a laser lighthouse for a planar position detection device that determines the coordinates of a measurement point using the LH principle.

(Prior art) Conventionally, the method of determining the position coordinates of a measurement point from two laser lighthouses is to install a laser lighthouse that rotates and irradiates a beam of light at two reference points at an even rotational speed, and connect the two points. The diagonal straight line is used as a reference line, and on the other hand, a light detection sensor and a time measurement device are provided at the measurement point, and the light detection sensor detects two laser beams rotating in opposite directions from the laser lighthouse,
The time interval to be detected is totaled by a time measuring device, and the output is inputted to a calculation device to calculate the angle between the total point 1-1 and the reference line, and the angle and the pre-measured reference are calculated. It was a method of calculating the coordinates of a total of dl1 points from the distance between points (for example, Japanese Patent Application Laid-Open No. 127682/1982).
.

The laser lighthouse used in this method has a pentaprism in the center of the rotary table, a compound prism including a beam splitter outside the prism, and two mirrors fixed at right angles to each other above the pentaprism. , a laser beam from a laser light source provided on the rotation axis of the rotary table is guided to a pentabrism, a compound prism, and a two-sided reflecting mirror, and the laser beam is split into two by a beam splitter of the compound prism.
The laser beams are emitted as laser beams rotating in opposite directions (see Japanese Patent Laid-Open No. 63-55481).

This laser lighthouse needed to be installed horizontally, and was leveled using a bubble tube.

(Problem to be solved by the invention "X1") When the above-mentioned conventional laser lighthouse is installed in a place with soft ground such as a land reclamation site, the tripods etc. that support the laser lighthouse after leveling are It may sink and become unleveled, making it difficult to form and maintain a highly accurate horizontal beam.
In such a case, it is necessary to readjust the level again, which poses a problem of poor workability.

The present invention aims to solve such problems.

(Means for Solving the Problems) In order to achieve the above object, the present invention includes a first optical member that bends the traveling direction of the laser beam at right angles in the center of the turning table, and a first optical member on the outside thereof. A second optical member is installed that emits part of the incident laser beam as it is and emits the remaining part in a direction opposite to the direction of incidence, and above the first optical member, one mirror surface is perpendicular to the other mirror surface. A two-sided reflecting mirror is fixed, a laser light source is provided on the rotating shaft of the rotary table, and the laser light emitted from the laser light source is guided to the first and second optical members and the two-sided reflecting mirror, so that the outer In the planar position detection device Kawa laser lighthouse, which rotates two laser beams emitted from each other in opposite directions, the laser light source is suspended by a suspension line and placed below the rotating table. do.

(Function) Even if the main body of this laser lighthouse is tilted due to the soft ground, the laser light source is suspended by a hanging wire, so the laser light emitted from the laser light source will continue to head in the vertical direction.
The directions of the laser beams rotated and emitted from the second optical member and the dihedral reflecting mirror still maintain the horizontal direction.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

In the drawings, reference numeral 1 denotes a U-shaped mounting frame (not shown) that is placed on the ground using, for example, three legs, and its lower horizontal portion 1a
A rotary table 3 rotated by a drive motor 2 is assembled in the mount. An opening 3a for transmitting laser light is formed at the center of rotation of the rotary table 3, and a Venta prism 4 is installed at the position of this opening 3a. Further, on the rotary table 3, a compound prism 5 having a beam splitter in the optical axis direction of the pentagonal prism 4 is installed. A two-sided reflecting mirror 6 is attached to the upper horizontal part 1b of the mounting frame 1, and the intersection part 1 of the two mirror surfaces 6a and 8b of this two-sided reflecting mirror 6 is the rotation axis of the drive motor 2 (laser optical axis 12). 11. The drive motor 2 in the drawing is described as a brushless motor, but the rotary table 3 can be used with a belt and motor.
may be rotated. A brushless motor has a plurality of coils arranged around the outer periphery of the shaft, and sequentially applies current to rotate the rotary shaft.A bearing 17 is used on the shaft to ensure smooth rotation.

The composite prism 5 has two reflecting surfaces 5a and 5b forming an angle of 90 degrees, and the reflecting surface 5a serves as a beam splitter, so that the laser beam 11 incident from the horizontal direction is
is divided in the beam splitter, and part of it! 2 is emitted to the outside as it is, and the rest! 3 is a reflection 5a, 5
It is reflected at b and exits in a direction opposite to the direction of incidence. The two-sided reflecting mirror 6 is assembled so that the two mirror surfaces 6a and 6b are at right angles, and the laser beam 13 is emitted in a direction opposite to the direction of incidence. The mirror 6a, 6b
The shape of is rectangular, and the direction perpendicular to the plane of the paper is the longitudinal direction. Further, a balancer 18 is provided on the rotating table 3 so that the weight of the composite prism 5 and the pentaprism 4 is uniformly applied to the rotating shaft, thereby preventing vibrations caused by rotation.

In the drawing, 8 is a laser light source (for example, a semiconductor laser), and the laser light source 8 is placed and fixed upward on a support 9, and this support 9 is suspended in the direction of gravity by, for example, three hanging wires lO, and the laser light source 8 is Even if the lighthouse body is tilted, the pendulum action of the laser light source 8 ensures that the optical axis L2 connecting the collimator lens 11 and the laser light source 8 is always located on the vertical axis, and the vertical laser light l is always incident on the Venta prism 4. It is supposed to be done. The support base 9 has a cylindrical conductive cylindrical portion 12 on its outer periphery, and a conductive outer cylindrical body 13 is provided across the cylindrical portion 12 with a small gap. Cylindrical part l2
The outer cylindrical body l3 constitutes a damper mechanism that dampens the swinging of the support base 9. The laser light source 8 is on the focal length of the collimator lens 11.

Further, in the drawing, l4 is an oscillator, and the oscillator l4 is connected to the signal detection circuit 15 and the cylindrical portion l2. The capacitance formed between the cylindrical portion l2 and the outer cylinder 13 changes as the laser lighthouse main body is tilted, and the signal detection circuit l5 changes its output due to this change in capacitance. The signal detection circuit 15 latches this signal when it outputs a signal equal to or higher than the reference value, and this signal energizes the notification circuit 1B such as a lamp lighting circuit or an alarm circuit, so that the laser lighthouse body is tilted at a predetermined inclination or higher. It is designed to notify you that the

Next, to explain the operation of this embodiment, the drive motor 2
The rotary table 3 rotates clockwise, and the Venta prism 4 and compound prism 5 also rotate unevenly in the same direction at a predetermined speed. Laser light emitted from laser light source 8! 1 is made into parallel light by a collimator lens 1l and enters a pentagonal prism 4, whose optical axis is bent by 90'' and passes through a compound prism 5.
Head to. This laser beam l, is split into two by the beam splitter 5a of the composite prism 5, and one laser beam!
2 is emitted outward as clockwise parallel laser light cw. The other laser beam l, split by the beam splitter, is reflected by the reflecting surface 6b, further reflected by the dihedral reflector 6, and is reflected as a counterclockwise parallel laser beam CCV by the dihedral reflector 7. It emits light while being reflected by.

(Effects of the Invention) Since the present invention has the above-described configuration, even if the laser lighthouse is tilted, the laser light emitted from it is always maintained horizontally, thereby eliminating problems such as releveling as in the conventional method. This has the effect of improving work efficiency.

[Brief explanation of drawings]

The drawing is a cross-sectional view of one embodiment of the invention. 1...Mounting stand 3...Rotary table 4...Venta prism 5,. ．． Composite prism 6...Double reflecting mirror 8...Laser light source IO...suspension line Patent applicant: ΔP1 Co., Ltd.
Rihito Kitamura Kingai 3 people

Claims (1)

[Claims] At the center of the rotating table, there is a first optical member that bends the traveling direction of the laser beam at right angles, and on the outside thereof, there is a first optical member that outputs a part of the incident laser beam as it is and outputs the remaining part in the opposite direction to the incident direction. A second optical member is installed, a two-sided reflective mirror in which one mirror surface is perpendicular to the other mirror surface is fixed above the first optical member, and a laser light source is provided on the rotation axis of the rotary table, and the laser light source A planar position detection device that rotates two laser beams emitted outwardly in opposite directions by guiding laser beams emitted from a light source to the first and second optical members and a two-sided reflecting mirror. 1. A laser lighthouse for a planar position detection device, characterized in that the laser light source is suspended by a hanging line and placed below the rotary table.