JP2505644Z - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial application field) This invention relates to a reflector device for observing a bubble tube in a surveying instrument. (Prior art) In a surveying instrument, especially in a level with an automatic correction mechanism (compensator) which is currently frequently used in an automatic level, a bubble tube is used to check whether or not the level is placed almost horizontally on a tripod. (Mainly a circular bubble tube). As is well known, these bubble tubes are usually viewed from above due to the structure using liquid. When visually recognizing the position of the bubble, there is a method of directly recognizing the position with the eyes. In general, however, a method of indirectly recognizing the position using a reflecting mirror or a pentaprism is employed. This is because the surveyor can check the bubble position from the eyepiece side of the surveying instrument, which is convenient. FIGS. 3 and 4 show a conventional example in which the bubble tube is visually recognized indirectly. Third
The figure shows an example using a reflecting mirror. The bubble tube 2 attached to the level body 1 is visually recognized from almost directly above the eyepiece at the position of the eyepiece by the reflecting mirror 3 installed at approximately 45 ° thereon. Is done. Although this configuration is simple, the moving direction of the bubble image is opposite to the actual moving direction of the bubble, and it is difficult to perform a level operation. FIG. 4 shows an example in which a pentaprism 4 is used in place of the reflecting mirror 3. In this prism, since the optical path is reflected twice, the moving direction of the bubble image becomes the same as the actual moving direction of the bubble. Easy to do. However, the pentaprism requires polishing of a total of four surfaces, an input / output surface and two reflection surfaces, and furthermore, the input / output surface is coated with an anti-reflection coating, and the two reflection surfaces are metallized. A film is deposited. For this reason, it is unavoidable to be expensive, and in fact, it is used only for high-grade surveying instruments. (Problems to be Solved by this Invention) In view of the above situation, this invention provides an optical system in which the moving direction of the bubble image is the same as the actual moving direction of the bubble by using a reflecting mirror. The purpose of the present invention is to make it possible to easily perform a leveling operation by using a visual recognition device for a bubble tube. (Means for Solving the Problem) The reflecting device for a bubble tube of the present invention includes a first reflecting mirror for reflecting an image of a bubble forward and downward above a bubble tube attached to a surveying instrument main body, and the first reflecting mirror. Is provided with a second reflecting mirror which is opposed to the reflecting mirror at an angle of approximately 45 °, thereby reflecting the image of the bubble in the optical axis direction of the level body. These reflecting mirrors are configured so that a U-shaped spring member having two mirror surfaces is fitted to a support frame formed by die casting or resin molding. (Example) Hereinafter, an example of this invention is shown. FIG. 1 shows an embodiment of a reflector device for a bubble tube according to the present invention, in which a first reflector 5 is provided above a bubble tube 2 attached to a level main body 1 and has an angle of approximately 45 °. The second reflecting mirror 6, which is opposed to the supporting frame 8, is used as a reflecting mirror device (optical element).
It is arranged above. The bubble image is reflected by the second reflecting mirror 6 in the direction of the eyepiece 7 so that the bubble position can be visually recognized at the eyepiece position. The reflecting mirrors 5 and 6 are fixed on the same support frame 8 and are fixed to the level body with screws or the like. The support frame 8 is preferably formed by die-casting or resin, and a member 9 in which two mirrors are integrally formed in a U-shape is preferably fitted by utilizing its spring property. The accuracy of the reflector device made in this way is inferior to that of a pentaprism made of conventional glass, but is sufficient for the purpose of the present invention. The perpendicularity accuracy of a pentaprism conventionally used as an optical element is generally within 10 ″, which causes an increase in cost. However, for example, the distance from the reflecting mirror device to the position of the bubble is set to 60〜. If the right-angle accuracy is reduced to about 20 'when the distance is set to 100 mm, a position deviated from the center of the bubble by 0.36 to 0.6 mm when viewed from the level of the optical axis. If it is shifted, it is easy to see the entire bubble by slightly raising and lowering the eyes, and there is no practical problem. (Effect of the invention) This invention is based on the pentaprism using two reflecting mirrors as described above. Since the reflecting mirror device that realizes the same optical path as that of the above is used, the level operation becomes easy, this can be realized at low cost, and further, there is an effect that it is lighter than the pentaprism. Since the spring is fitted to the shaped support frame by utilizing the spring property, the number of parts is smaller than that of a method in which two reflecting mirrors are separately incorporated, and it is not necessary to adjust the angle in assembling. By fitting the reflecting mirror member after the assembling work, a problem such as damage to the mirror surface due to the assembling work does not occur, and a reflecting mirror device excellent in workability can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view of a level having a bubble tube visual recognition device using the reflector device of the present invention, FIG. 2 is a perspective view showing details of the configuration of the reflector device, FIG. FIG. 4 is a side view of a level having a conventional bubble tube visual recognition device. 1: Level body 2: Bubble tube 3: Reflecting mirror 4: Penta prism 5: First reflecting mirror 6: Second reflecting mirror 7: Eyepiece 8: Supporting frame 9: U-shaped mirror member

Claims (1)

[Claims for utility model registration] Die-casting or resin-molded support in a surveying instrument that checks the inclination by the position of the bubble using a reflector device that visually changes the image of the bubble by changing the optical path in the 90-degree direction by two-sided reflection A U-shaped resilient member having two mirror surfaces formed so that an image of a bubble changes an optical path by 90 degrees in a frame, and is fitted to the supporting frame.