JPH0420917A - Clamping mechanism - Google Patents

Abstract

PURPOSE:To enhance the clamp precision by forming a clamping band and a housing as independent bodies and providing a playing part where only both sides are abutted on a shaft in the part where the shaft is pressed on the inside of the clamping band. CONSTITUTION:When a clamping screw 14 is tightened, the shaft is pushed by a bush 15 of the screw 14 and is pressed to the side of the playing part 16 of a clamping band 11. Consequently, the shaft is surely supported at three points of the bush 15 and both corner parts 16a and 16b of the playing part 16, therefore, the shaft is not rotated in the clamping band to improve the clamp precision even if the clearance between the clamp band 11 and the shaft is increased. Since the playing part 16 has a prescribed length (l), a sufficient clamping strength is obtained. Since the clamping band 11 is provided with the playing part 16 in such a manner, distortion, deformation, etc., of the clamping band 11 is not transmitted to a housing 10 even if the distortion and deformation are generated, and the shaft is supported at three points in the clamping band 11 to enhance the clamp precision.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a clamp mechanism, and particularly to a lamp mechanism suitable for supporting a lens barrel of an astronomical telescope.

<Prior art and problems to be solved by the invention> FIG. 3 is a diagram showing a conventional example of a clamp mechanism.

This clamp 1 includes a housing 2 which is a main body part, and a split type clamp bundt 3 integrated with this housing 2.
It consists of. Also, both ends 3 of the clamp band 3
Clamp screws 4 are attached to a and 3b. S is a shaft to be fixed, and fixing is completed by setting this shaft S in the clamp band 3 and tightening the clamp screw 4.

However, in this type of clamp mechanism, when the clamp screw 4 is tightened, one end 3a of the clamp band 3 is attracted to the other end 3b, and the shaft S is accordingly slightly Since the shaft S rotated toward the A side, the position of the shaft S within the clamp band 3 was not determined, resulting in poor clamping accuracy. In order to suppress such rotation of the shaft 3, it may be possible to reduce the clearance C between the clamp band 3 and the shaft S. If so, the clearance C may be reduced at low temperatures etc.
is undesirable because it becomes too small and may impede the free rotation of the shaft S within the clamp band 3.

FIG. 4 is a diagram showing another conventional example of the clamp mechanism. This clamp 5 also has a structure in which a housing 6 and a clamp band 7 are integrated, but differs from the previous example in that the clamp band 7 is not of a split type. Further, a clamp screw 8 is also attached to the housing 6 side, and the tip of this clamp screw 8 is attached to the shaft S in the clamp band 7.
It is designed to be fixed by pressing it.

However, in this type of clamp mechanism, although the shaft S does not rotate as in the conventional example, the tightening force of the clamp screw 8 acts directly on the shaft S and the clamp band 7. Therefore, distortion occurs in the shaft S and the clamp band 7, and as a result, clamping accuracy is adversely affected.

Furthermore, since a clearance C is created on the left and right sides of the shaft S, the tightening force of the clamp screw 8 causes escape force to be generated in either the left or right direction of the shaft S, which may adversely affect clamping accuracy. Incidentally, if this clearance C is made small, the same problem as in the prior art example described above will occur.

The present invention has been made by paying attention to such conventional technology, and aims to provide a clamp mechanism that can solve the above-mentioned problems.

Means for Solving the Problem> The clamp mechanism according to the present invention separates the clamp band and the housing, and provides a relief part in the part of the inside of the clamp band against which the shaft is pressed, so that only both ends contact the shaft. It is something.

<Embodiment> Hereinafter, a preferred embodiment of the present invention will be described based on FIGS. 1 and 2. Note that explanations that are redundant with those of the prior art will be omitted.

In the clamp 9 according to this embodiment, a housing 10 and a clamp band 11 are separate. That is, the housing IO is provided with a mounting bracket 12, and the base end portion 11a of the non-dividable clamp band 11 is fixed to the mounting bracket 12 with a pair of set screws 13. A clamp screw 14 is screwed into the base end 11a of the clamp band 11, and the shaft S inside the clamp band 11 can be pressed and fixed by a bush 15 at the tip of the clamp screw 14. Base end portion 11a of this clamp band 11
On the opposite side, that is, on the part against which the shaft s is pressed, a relief part 16 of a predetermined length l is recessed.

Therefore, as the clamp screw 14 is tightened, the shaft S is pushed by the pusher unit 5 of the clamp screw I4, and is pushed toward the relief part 6 of the clamp band II. Therefore,
The shaft S has both corner portions 16a of the bushing 15 and the relief portion 16.
, 16b. Therefore, even if the clearance C between the clamp band 11 and the shaft S is large, the shaft S is supported by the clamp band 11.
There is no rotation within the clamp and the clamping accuracy is high. In addition, since this relief portion 16 has a predetermined length l,
Sufficient lamp intensity can be obtained.

Furthermore, as the clamp screw I4 is tightened, a reaction force is generated in the direction B (see FIG. 21) within the clamp band 11, so the clamp band 11 is deformed and the tension between the shaft S and the clamp band 11 is Although the clearance C also changes, since the clamp band 11 and the housing 10 are separate bodies, the above-mentioned deformation and distortion (stress) that occurs in the clamp band 11 is not applied to the housing 10.
Less influence on clamping accuracy. Further, since the clamp band 11 and the housing 10 are separate, it is advantageous in terms of work when assembling the shaft S and the clamp 9.

Incidentally, in the above explanation, an example was shown in which the relief part 16 was provided in order to support the shaft S at three points, or if the shaft S could be supported at three points, a pair of protrusions etc. could be provided.
A relief portion may be provided between the protrusions.

<Effects of the Invention> Since the clamp mechanism according to the present invention has the content as explained above, even if distortion or deformation occurs in the clamp band, it will not be transmitted to the housing, and the shaft can be supported at three points within the clamp band. Therefore, the clamping accuracy is very high, making it ideal for supporting the lens barrel of an astronomical telescope.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing a clamp mechanism according to an embodiment of the present invention, Fig. 2 is a side view of the clamp mechanism showing a cross section of the proximal end of the clamp band, and Fig. 3 is a conventional example of the clamp mechanism. FIG. 4 is a partially sectional side view showing another conventional example of a clamp mechanism. 9 ”°'° Clamp 10 Bent Housing 11 --- Clamp band 14 --- Clamp screw 16 --- Relief section S --- Shaft diagram Clamp 1 Clamp 1 oscilloscope / Diagram

Claims (1)

[Claims] A clamp mechanism in which a shaft of a predetermined diameter is inserted into a clamp band provided on a housing, and the shaft is pressed and fixed by a clamp screw attached to the clamp band, wherein the clamp band and the housing are separated. What is claimed is: 1. A clamp mechanism characterized in that a clamp body is provided with relief portions in which only both ends abut the shaft at a portion of the inner side of the clamp band against which the shaft is pressed.