JPH0249531Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field This invention relates to a survey instrument that adjusts the sighting axis by coarsely and finely moving the main body of the telescope.

BACKGROUND OF THE INVENTION In order to accurately align the sighting axis, surveying instruments such as Rebel and Transit rotate the telescope main body coarsely and finely around a vertical or horizontal axis.

Conventionally, as a mechanism for coarsely and finely moving the telescope main body of this type of surveying instrument, there is a mechanism applied to the level shown in FIG. A vertical rotation shaft 2a integrally provided with the telescope main body 2 is rotatably attached to a bearing 1a of a lower plate 1 fixed to a tripod (not shown), and a rotation arm 3 is attached to the outer periphery of the bearing 1a. is attached to the lower plate part 1 and the telescope main body part 2 on both upper and lower surfaces so as to be rotatable with a predetermined amount of rotational force. Coarse and fine movements of the telescope main body 2 are performed by the difference in frictional forces between the upper and lower surfaces of the rotating arm 3 and the telescope main body 2 and the lower plate 1, respectively. That is, by appropriately adjusting the difference in frictional force, when a predetermined amount of rotational force or more is applied to the rotating arm 3, the rotating arm 3 slides and rotates between the lower plate 1 and the telescope main body 2. When it rotates and the amount of rotational force is less than a predetermined amount, relative sliding occurs between the telescope main body 2 and only the telescope main body 2 rotates. The former is gross movement, and the latter is fine movement.

However, in the case of a surveying instrument with such a mechanism, in order to create a difference in the frictional force between the upper and lower surfaces of the rotating arm 3, the contact area with the lower plate part 1 must be made large, and the rotating arm 3 is In addition, there is a problem in that the predetermined amount of rotational force must be set to a large value, an operating force is required to adjust the collimation axis, and there is variation in the amount of rotational force for fine or coarse movement.

Further, as another conventional example, there is one that is provided with a clamp that fixes the rotating arm to the lower plate during fine movement. The amount of rotational force is determined by the screw engagement between the shaft and the bearing, oil, etc., and generally a small value may be sufficient. However, there is a problem that as the number of parts increases, the operating force such as clamp operation becomes worse.

Purpose This invention was devised in view of the problems of the prior art, and the purpose is to provide a compact surveying instrument with good operability that can be operated with a stable and small amount of rotational force.

Configuration In order to achieve this objective, the rotary arm is provided with a spring means that applies a biasing force toward the center of the bearing against the outer circumferential surface of the bearing.

This invention will be explained below based on the drawings.

FIGS. 2 to 5 are diagrams showing an example in which this invention is applied to a level. Reference numeral 10 in the figure indicates a telescope main body, which is rotatably provided on a tripod mount 20 via a lower plate 30. The lower plate 30 can generally be horizontally adjusted using three adjustment screws 31. A bearing portion 32 is formed on the lower plate 30,
A vertical rotation shaft 11 provided integrally with the telescope main body 10 is rotatably mounted there. Further, a rotating arm 40 is rotatably mounted on the outer periphery of the bearing portion 32. This rotating arm 40 is
The arm part 41 and the annular part 42 are integrally formed, and the bearing part 32 is formed on the inner peripheral surface 42a of the annular part 42.
A spring means is provided which applies a biasing force toward the center of the inner circumferential surface 42.
It is formed to protrude from the inner circumferential surface 42a concentrically with a. This hanging 43 is provided with at least one slot 43a along the axial direction to provide sufficient springiness. Further, an appropriate number of screws 44 facing the center are provided in this annular portion 42 so that the tips thereof can come into contact with the hangings 43, so that the wobbling of the rotating arm 40 or the spring force of the hangings 43 can be adjusted. Although the rotating arm 40 having such a structure is generally integrally molded from synthetic resin, it is not limited to synthetic resin, and the hanging arm 43 can be made as a separate component.

Reference numeral 12 denotes a skirt portion that is integral with the telescope main body 10 and covers almost the entire lower plate 30 and the rotating arm 4.
It covers 1. This skirt portion 12 has a fine adjustment screw 1 that can freely move forward and backward in a plane perpendicular to the vertical rotation axis 11.
3 are screwed together, and the spring 45 is fixed to the rotating arm 40 so that the tip of the fine adjustment screw 13 is always in contact with the arm part 41 of the rotating arm 40. The spring 45 is locked to the protrusion 12a formed on the skirt part 12. (See Figure 4). The strength of this spring 45 is
The frictional force due to the biasing force toward the center of the spring means 43 is set to be greater than the amount of rotational force.

Function Next, we will explain the use of such a surveying instrument and explain the function of the device.

First, the lower plate 30 on the tripod 20 is leveled by rotating the adjusting screw 31. Next, hold the telescope body 10 in your hand and roughly align the sighting axis with the target object. In this way, for coarse movement, the telescope main body 10 is held and rotated directly by hand. Thereafter, by rotating the fine adjustment screw 13 and moving it forward and backward, the telescope main body 10 is finely moved to perform accurate collimation axis adjustment.

Coarse movement and fine movement will be explained in detail with reference to FIG. 4. First, in the case of coarse movement, the following operation is performed. When the telescope main body 10 is rotated in the opposite clockwise direction, the tip of the fine adjustment screw 13 pushes the rotation arm 40, and the rotation arm 40 rotates together. When the telescope body 10 is rotated clockwise, the rotation arm 40 is moved by the spring 4 so that the arm 41 is always in contact with the tip of the fine adjustment screw 13.
5, and since the spring force of this spring 45 is greater than the frictional force between the hanging portion 43 and the bearing portion 32, the rotating arm 40 is similarly rotated clockwise. This frictional force becomes a predetermined amount of rotational force, but it can be made smaller than the frictional force between the upper and lower surfaces of the conventional rotating arm.
The spring force, that is, the frictional force, can be changed by moving forward and backward.

Next, in the case of slight tremors, the following actions are taken.
This slight movement can be achieved by slightly rotating the telescope main body 10. Therefore, when the fine movement screw 13 is turned to the right, the fine movement screw 13 moves toward the inside of the skirt portion 12.
enters. However, since the force of the fine adjustment screw 13 entering and pushing the rotating arm 40 is smaller than the frictional force of the rotating arm 40 that produces the set amount of rotational force, the rotating arm 40 is There is no relative movement. Therefore, the telescope main body 10 rotates clockwise by receiving a reaction force from the rotation arm 40 by an amount corresponding to the amount of intrusion. Conversely, when the fine adjustment screw 13 is turned to the left, the tip of the fine adjustment screw 13 tends to separate from the arm portion 41 of the rotation arm 40. However, the spring 45 is always
The tip of the fine adjustment screw 13 is about to come into contact with the tip of the fine adjustment screw 13, and since the rotation arm 40 does not rotate as described above, the spring 45 pushes the protrusion 12a and the telescope main body 10 corresponds to the retraction of the fine adjustment screw 13. Rotates counterclockwise by the rotation angle.

Although the above description has been made regarding a device with a vertical rotation axis such as a level of a surveying instrument, it goes without saying that this invention can also be applied to a device with a horizontal rotation axis such as a transit.

Effects As explained above, in the surveying instrument of this invention, the amount of rotational force can be set small, so the variation in the amount of rotational force that starts moving during coarse or fine movement is small and stable. Furthermore, since the amount of rotational force can be set small, the length of the arm portion can be shortened, and since the annular portion is small and there is no need to add parts such as a clamp, the rotating arm can be made small. Therefore, the surveying instrument itself can be made smaller and lighter. For these reasons, this surveying instrument has excellent operability.

[Brief explanation of the drawing]

Figure 1 is a partial sectional view of a conventional surveying instrument, Figure 2 is an overall perspective view of the surveying instrument of this invention, Figure 3 is a cross-sectional view of Figure 2, and Figure 4 is a cross-sectional view of Figure 2. 5 are partial perspective views of the rotating arm of the surveying instrument of this invention. DESCRIPTION OF SYMBOLS 10...Telescope main body part, 11...Vertical rotation axis (rotation axis), 12...Skirt part, 12a...Protrusion part, 13...Fine screw, 30...Lower plate, 32...
Bearing part, 40... Rotating arm, 41... Arm part, 42... Annular part, 42a... Inner peripheral surface, 43...
...Tare (spring means), 43a...Suriwari, 44...
...screw, 45...spring.

Claims (1)

[Claims for Utility Model Registration] (1) A rotating shaft integrally provided with the telescope main body is rotatably mounted on a bearing, and a rotating arm can be rotated with a predetermined amount of rotational force around the outer periphery of the bearing. a fine adjustment screw screwed into the telescope main body so as to be movable forward and backward, and the rotating arm are engaged so as to be in constant contact with each other, and the telescope main body is rotated with the amount of rotational force or more; In a surveying instrument that causes a rotating arm to move coarsely in cooperation and moves the fine adjustment screw forward and backward to slightly move the telescope main body with less than the amount of rotational force, the rotating arm includes: A surveying instrument characterized in that a spring means is provided for applying a biasing force toward the center of the bearing portion and determining the amount of rotational force. (2) The spring means has at least one slot extending from the inner circumferential surface concentrically with the inner circumferential surface facing the outer circumferential surface of the bearing portion of the rotating arm and extending from the inner circumferential surface, and axially extending along the bow. A surveying instrument characterized by being equipped with.