JP3122517B2 - Surveying instrument for forming reference plane - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surveying instrument for forming a horizontal reference plane by emitting light in almost all directions in a horizontal plane.

[0002]

2. Description of the Related Art Conventionally, levels as shown in FIGS. 3 and 4 are known as surveying instruments for forming a reference plane.

In the level shown in FIG. 3, a laser light source 2 is disposed at the bottom of a level housing 1, and a collimating lens 3 is fixed above the light source 2. The light source 2 is located on the optical axis of the collimating lens 3. The distance between the collimator lens 3 and the light source 2 is the focal length of the collimator lens 3, and the light from the light source 2 is converted into a parallel light beam by the collimator lens 3. Above the collimating lens 3, a conical mirror 4 with its apex downward is provided. The mirror 4 is suspended by a suspending member 5 suspended from the housing 1, and the vertex of the mirror 4 is positioned on the optical axis of the collimator lens 3. The reflecting surface of the mirror 4 has an angle of 45 ° with respect to the vertical line. The suspension member 5 is designed so that when the housing 1 is inclined by θ with respect to the horizontal plane 6, the mirror 4 is inclined by θ / 2 with respect to the vertical line 7.

At this level, as shown in FIG. 4, when the housing 1 is inclined by θ with respect to the horizontal plane 6, the light source 2 and the collimating lens 3 are also inclined by θ with respect to the vertical line 7, and the parallel light flux of the collimating lens 3 is It is inclined by θ with respect to the vertical line. On the other hand, the mirror 4 is moved vertically 7
, The incident angle at which the parallel luminous flux of the inclined collimating lens 3 enters the reflecting surface of the inclined mirror 4 is θ compared to the incident angle when the inclination is not inclined.
/ 2 decrease. When the incident angle of the incident light to the mirror is α, if only the mirror is inclined by θ / 2 in a direction to decrease the incident angle of the incident light, the reflection angle of the light becomes the reflection angle α with respect to the original mirror surface. Θ with respect to.

Therefore, when the mirror 4 is rotated by θ / 2, if the incident angle θ is further increased from the original incident angle of the incident light, the reflected light can be returned to the original angle before the mirror 4 is rotated. And laser light can be emitted in almost all directions in the horizontal plane.

[0006]

However, in such a conventional reference plane forming surveying instrument, when the housing 1 is tilted by .theta. With respect to the horizontal plane 6, the mirror 4 is tilted by .theta. / 2 accurately. The structure of the suspension member 5 is complicated, requires a high level of assembling technology, and the suspension member 5 of the mirror 4 has a variation in material and the like, so that there is a problem that it takes time to adjust this.

[0007]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a reference plane forming surveying apparatus which is relatively simple in construction, easily adjusts for variations, and can form a substantially horizontal reference plane accurately following the inclination of a housing. The purpose is to provide instruments.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a reference plane forming surveying instrument according to the present invention provides a light inclined at 45 ° to a central axis and parallel to the central axis at right angles to the central axis. A reflecting member having a reflecting surface capable of emitting light, and a light source unit disposed on a central axis of the reflecting member and facing a vertex of the reflecting surface, the light source unit and the reflecting member A reference plane forming surveying instrument provided with a collimating lens for converting the light from the light source unit into a parallel light flux and entering the reflecting surface of the reflecting member, between the collimating lens and the effective length of the focal length of the collimating lens. It is characterized in that it is suspended at the end.

[0009]

According to the surveying instrument for forming a reference plane according to the present invention, the collimating lens is simply suspended,
The horizontal reference plane can be formed accurately.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A reference surface forming surveying instrument according to the present invention will be described below with reference to the drawings.

FIG. 1 shows a main structure of a level as a surveying instrument for forming a reference plane according to the present embodiment. Reference numeral 10a denotes an upper wall surface of a level housing, and 10b denotes a lower wall surface of the housing. When the case is vertically oriented, the upper wall surface 10a is oriented horizontally.

A conical mirror 11 is fixed to the upper part of the housing. A central axis 12 passes through the vertex of the mirror 11, and the central axis 12 is perpendicular to the upper wall surface 10a. Although the mirror 11 is a conical mirror in this embodiment, it may be a regular polygonal pyramid, a truncated cone, a regular polygonal truncated cone, or a prism. The mirror 11 has a reflecting surface 13 having a sectional shape at an angle of 45 ° with respect to the central axis 12. Central axis 1 passing through the vertex of mirror 11
The central portion of the light source unit 14 is located below the light source unit 2.

A collimating lens 15 is horizontally suspended between the light source unit 14 and the mirror 11.

The tilting mechanism for suspending the collimating lens 15 is constituted by a linear member 17 such as a string or a wire which is soft and hard to extend. The linear member 17 is suspended from the upper wall surface 10a so as to be freely tiltable. Wire member 17
Is the effective length L of the collimating lens 15 suspended from the upper wall surface 10a of the housing.
Is set equal to There are four to five places where the collimating lens 15 is suspended so as to tilt in parallel with the upper wall surface 10a of the housing.
It is sufficient to suspend a necessary and sufficient portion to cause the 5 to follow the inclination of the upper wall surface 10a.

The distance between the collimating lens 15 and the light source unit 14 is set to be equal to the focal length F of the collimating lens 15 when the casing is erected and the collimating lens 15 is horizontal. Is emitted by the collimating lens 15 as a parallel light beam.

Next, a description will be given of how the reflected light of the mirror is radially reflected toward the horizontal reference plane when the level of the present embodiment is inclined with reference to FIG.

At the level according to the present embodiment, when the optical axis 16 of the collimating lens 15 extends in the vertical direction, the light source unit 14 is located on the optical axis 16 of the collimating lens 15 and the central axis 12 of the mirror 11 is Is a collimating lens 1
5, the reflecting surface 13 of the mirror 11 has an angle of 45 ° with respect to the central axis 12.

When the housing is inclined by θ with respect to the vertical line 18 from this state, the light source unit 14 fixed to the housing and the central axis 12 of the mirror 11 are inclined by θ with respect to the vertical line 18 and the optical axis of the collimating lens 15 is The center 15a is shifted laterally by a distance A with respect to the center axis 12.

The distance A from which the light source unit 14 deviates from the optical axis 16 of the collimating lens 15 is expressed as follows: A = Ltan θ =
Ftan θ, and when θ is a small amount, A ≒ Fθ. Therefore, the angle θ ′ formed between the optical path passing through the optical center 15a of the collimating lens 15 and the central axis 12 is equal to θ, and the parallel light flux emitted from the collimating lens 15 is
The reflection surface 13 of the mirror 11 at an inclination of θ + θ ′ = 2θ
Will be incident.

On the other hand, the reflection surface 13 of the mirror 11 is inclined by θ with respect to the vertical line 18 due to the inclination of the housing, and the reflected light 19 after the inclination of the housing is reflected in the horizontal direction by canceling the angle. Become.

Therefore, according to the level of this embodiment, even if the housing is inclined, the center axis 12 of the mirror 11 remains in a horizontal reference plane.
Can be radiated in substantially all directions around the center, and an accurate horizontal reference plane can be obtained based on the angle of the reflected light.

Moreover, since the collimating lens 12 is suspended by the linear member 17, the followability is good, the configuration is simple, the assembling is not troublesome, and the possibility of failure is small.

In this embodiment, the collimating lens 12 is suspended by four linear members. However, as shown by a broken line in FIG. 2, three to four collimating lenses 12 are provided around the point 18a. It may be suspended by a linear member. In that case, the effective length of the suspension is the distance L between 18a and the lens optical center 15a.
Length.

In this embodiment, the collimating lens 1
2 is suspended from the upper wall surface 10a of the housing, but the vertical direction may be reversed and the collimating lens 12 may be supported by a parallel link mechanism or the like.

[0025]

As described above, the reference surface forming surveying instrument according to the present invention has a reflection surface having a reflecting surface inclined at 45 ° to the central axis and capable of emitting light parallel to the central axis at right angles from the central axis. A light source unit disposed on a central axis of the reflection member and facing a vertex of the reflection surface, and between the light source unit and the reflection member, from the light source unit. In a reference plane forming surveying instrument provided with a collimating lens that converts the light into a parallel light beam and enters the reflecting surface of the reflecting member, the collimating lens is suspended by the effective length of the focal length of the collimating lens. It is relatively simple and easy to adjust the variation, and can follow the inclination of the housing accurately and quickly to form a substantially horizontal reference plane.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a reference plane forming surveying instrument according to an embodiment of the present invention.

FIG. 2 is an explanatory view of a state where the reference plane forming surveying instrument according to FIG. 1 is inclined.

FIG. 3 is a configuration diagram of a conventional reference plane forming surveying instrument.

FIG. 4 is an explanatory view when a conventional reference plane forming surveying instrument is inclined.

[Explanation of symbols]

 10a: Upper wall surface of the housing 10b: Lower wall surface of the housing 11 ... Mirror 12 ... Central axis 13 ... Reflection surface 14 ... Light source unit 15 ... Collimating lens 16 ... Optical axis of the collimating lens 17 ... Linear member L ... Effective linear member Length F: focal length of collimating lens

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Ikuo Ishinabe 75-1, Hasunuma-cho, Itabashi-ku, Tokyo Topcon Co., Ltd. (56) References JP-A-48-37150 (JP, A) JP-A-2- 116708 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) G01C 5/00-5/02 G01C 15/00

Claims (1)

(57) [Claims] 1. A reflecting member having a reflecting surface inclined at 45 ° to the central axis and capable of emitting light parallel to the central axis at right angles from the central axis, and a reflecting surface on the central axis of the reflecting member and A light source unit disposed at a position facing the apex corner, and between the light source unit and the reflection member, the light from the light source unit is converted into a parallel light flux and incident on the reflection surface of the reflection member. A reference plane forming surveying instrument provided with a collimating lens, wherein the collimating lens is suspended by an effective length of a focal length of the collimating lens.