JPS5810088Y2 - pendulum braking device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a pendulum braking device installed in a surveying instrument to maintain a constant relationship with the direction of gravity.

Accurate surveying is obstructed when a pendulum in a surveying instrument undergoes various types of vibrations due to external vibrations, so various types of damping devices have been proposed to damp the vibrations of the pendulum.

In particular, the present invention relates to an improved damping device for a set of liquid dampers.

Conventionally, this type of braking device has a pendulum installed inside a sealed container, and the pendulum is braked by the viscous resistance of the liquid filling the container, but since the pendulum is inside the sealed container, it cannot be readjusted from the outside. Not only is this difficult, but the measurement of the tilt angle of the pendulum may be obstructed by the container or liquid, leading to errors, and it also requires sophisticated parts, resulting in high costs.

The present invention solves the above-mentioned drawbacks by positioning the pendulum outside the liquid-enclosed container, and even though the container has an opening, leakage of liquid from the container is prevented by a cylindrical wall provided on the inner surface around the opening. The purpose of the present invention is to provide a pendulum braking device that can prevent the above.

Next, the present invention will be explained based on the illustrated embodiment.
Reference numeral 1 denotes a pendulum installed inside the surveying instrument, and the pendulum 1 is suspended below a pedestal 4 by connecting hanging strings 3.3 to hanging devices 2 provided on both sides thereof.

A container 5 is arranged directly below this pendulum 1, and an opening 6 is bored in the upper surface of the container 5 at a position on the hanging extension line of the pendulum 1, and a cylindrical wall 7 is formed on the inner surface of the periphery of the opening. It is integrally molded.

Then, the connecting rod 8 extending downwardly from the lower surface of the pendulum 1 is inserted into the opening 6 of the container 5 and passed through the cylindrical wall 7 into the container 5.
A suitable amount of liquid 9 sealed inside the container 5
The free end of the connecting rod 8 is connected and fixed to the brake element 10 located inside.

The amount of the liquid 9 enclosed in the container 5 is preferably such that the lower end of the cylindrical wall 7 does not touch the liquid level when the container 5 is tilted so as to raise the liquid level to the maximum level.

In the braking device having the above structure, when the pendulum 1 generates various vibrations due to external vibrations, the vibrations are transmitted to the damper 10, which is located in the liquid 9 of the container 5, through the connecting rod 8, and the vibrations are transmitted to the liquid 9. This makes it possible to suppress the vibrations that occur in the pendulum 1 due to the viscous resistance of the pendulum.

What is shown in FIG. 2 is a schematic diagram of the braking device of the present invention incorporated into an optical surveying instrument A such as an automatic level. A pendulum 1 attached to the human exit optical axis is suspended, and as described above, vibrations of the pendulum 1 caused by external vibrations are suppressed via a brake 10 placed in the sealed liquid 9 of the container 5. As a result, the tilt angle of the pendulum 1 can be accurately measured without being hindered by the vibration of the pendulum 1.

In this case, since the pendulum 1 equipped with a reflecting mirror 13 such as a prism is located outside the container 5, a particularly sophisticated optical member is required in the human exit light window of the container 5, as in the conventional liquid damper brake system. Therefore, it is possible to reduce costs.

Furthermore, what is shown in FIG. 3 is a schematic diagram in which the braking device of the present invention is applied in an electric inclinometer, in which a differential transformer 14 is arranged around a pendulum 1 suspended above the outside of a container 5. The differential transformer 14 sets the inclination angle of the pendulum 1 in the same way as in the case described above, and the vibration of the pendulum 1 is suppressed, so accurate measurement can be performed, and since the pendulum 1 is installed outside the container 5, Installation of the differential transformer 14 becomes easy,
and can be operated effectively.

In the above-described embodiment, the container 5 is provided directly below the suspended pendulum 1, but the arrangement of the pendulum 1 and the container 5 is not limited to the above-mentioned embodiment. Can be changed at any time as shown.

In other words, in FIG. 4, the container 5 is fixed by being displaced laterally from the position directly below the pendulum 1, and the connecting rod 8 extending from the pendulum 1 is extended laterally to open the opening provided on the side of the container 5. The brake member 10 is passed through the portion 6 and the cylindrical wall 7, and the distal end thereof protruding from the cylindrical wall 7 is bent and suspended to be fixed to the brake member 10, which is positioned in the sealed liquid 9.

Further, in FIG. 5, the container 5 is positioned above the pendulum 1, and the connecting rod 8 extending upward from the pendulum 1 passes through the opening 6 formed on the lower surface of the container 5 and the cylindrical wall 7. A brake member 1 is inserted into the interior, and its plunger tip side is bent down in a substantially U-shape to face the surface of the liquid 9, and the brake member 1 is loosely mounted on the outer periphery of the cylindrical wall 7.
It is connected and fixed to 0.

As explained above, the present invention has an opening on one side of the container and connects the pendulum to the damper located in the liquid sealed in the container via a connecting rod, so the pendulum can be placed outside the container. The pendulum can be easily readjusted at any time, and can be incorporated into various measuring instruments without being interfered with by the container or sealed liquid. Various vibrations generated in the pendulum can be effectively controlled through a damper inserted in the container. can be stopped and accurate measurements can be made.

Furthermore, according to the present invention, even if the measuring device is tilted even though the container has an opening, the cylindrical wall integrally formed on the inner surface of the periphery of the container opening effectively prevents the sealed liquid from leaking. The practical effects are extremely great, such as being able to prevent this, and being simple in structure and inexpensive to provide.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention; Fig. 1 is a front sectional view, Fig. 2 is a schematic diagram showing the state in which it is incorporated into an automatic level, and Fig. 3 is a schematic diagram showing the state in which it is incorporated in an electric inclinometer. Schematic diagram shown, 4th
This figure and FIG. 5 are main part sectional views showing another embodiment. 1...pendulum, 5...container, 6...
... Opening, 7 ... Cylindrical wall, 8 ... Connection rod, 9 ... Liquid, 10 ... Brake element.

Claims (1)

[Scope of utility model registration request] An opening is formed on one side of the container, and a cylindrical wall is formed on the inner surface of the periphery of the opening, and a pendulum placed outside the container is passed through the opening and the cylindrical wall at an appropriate location into the container. 1. A pendulum braking device, characterized in that a facing connecting rod is extended, and a brake is attached to the free end side of the connecting rod, the brake being positioned in a liquid sealed in a container.