JPH0449538Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a hub for fixing a rotary disk of, for example, an optical encoder to a rotating shaft.

(Prior Art) A side sectional view of the upper half of this type of conventional example is shown in FIG.

A cylindrical hub 2a is attached to the end of the motor rotating shaft 4 whose rotational position and rotational speed are detected, to which a load is not connected.

The rotary disk 1 is fixed to the rotating shaft 4 by providing a step on the opposite end surface of the hub 2a, fitting into the outer periphery of the step and bonding it to the severing side surface.

The hub 2a has a screw hole 5 extending from the outer peripheral surface toward the rotating shaft 4.
A set screw 3 is screwed into the screw hole 5 to fix the hub 2a to the rotating shaft 4.

(Problem to be Solved by the Invention) However, in such a conventional example, the hub 2a is fixed to the rotating shaft 4 using a set screw 3 and adhesive, but the entire inner circumferential surface of the hub 2a and the rotating shaft 4 It was difficult to achieve the precision of the two circumferential surfaces that fit and abut, and furthermore, the position of the screw hole 5 was not at the center of the width in the longitudinal direction of the rotating shaft 4 of the hub 2a. Therefore, it was difficult to adjust the perpendicularity of the rotating disk 1 to the rotating shaft 4.

That is, in the conventional example, there was a problem in that the rotary disk 1 was tilted to a large extent, and the surface runout of the rotary disk 1 was therefore large.

The object of the present invention is to overcome the difficulties of the conventional examples and to provide a hub for a rotating disk that does not fall when the hub is fixed to a rotating shaft and that causes almost no surface runout of the rotating disk. .

(Means for solving the problem) The present invention has a step in the outer diameter direction, fixes a rotating disk to the side surface of the step, fits the inner circumferential surface of the disk to the outer circumferential surface of the rotating shaft, and screws the disk to the rotating shaft. In the hub to be installed, a recessed hole is provided in the center of the inner circumferential surface to be fitted, and a threaded hole is drilled from the outer circumferential surface toward the rotating shaft, and a set screw is inserted to tighten the hub to the rotating shaft. This is a hub of a rotating disk that is provided approximately at the center of the hub's rotational axis in the longitudinal direction.

(Function) A recess-shaped gap is provided on the inner circumferential surface of the hub where it fits with the rotating shaft, so the rotating disk can be mounted based on the gap created by the fitting between the inner circumferential surface of the hub and the outer circumferential surface of the rotating shaft. It is possible to reduce the inclination of the surface, and since the position where the hub is screwed to the rotating shaft is located at the center of the hub's rotating shaft in the longitudinal direction, it is possible to obtain a perpendicularity of the rotating disk mounting surface to the rotating shaft. It is.

(Embodiment) FIG. 1 is a side view showing a cross section of the upper half of an embodiment of the present invention.

In all drawings, the same reference numerals represent the same or equivalent parts.

The present invention forms a recess 6 in the center of the inner circumferential surface of the hub 2 where it fits into the rotating shaft 4,
In addition, a screw hole 5 is bored and screwed at approximately the center position of the longitudinal width of the rotation shaft 4 of the hub 2 from the outer circumferential surface of the hub 2 toward the rotation shaft 4.

That is, in the present invention, the hub 2 is fitted to the rotating shaft 4 through the slightly thickened portions left at both longitudinal ends of the rotating shaft 4 of the hub 2.

Furthermore, the hub 2 of the present invention is screwed to the rotating shaft 4 at a substantially central location in the length direction of the rotating shaft 4 of the hub 2.

In this way, the rotating shaft 4 coated with adhesive
Insert the hub 2 to which the rotary disk 1 is adhesively fixed, and tighten the set screw 3.

[Effect of idea]

Thus, according to the present invention, since the fitting and adhesive fixing part between the hub and the rotating shaft has a recessed hole in the center, it is easy to ensure accuracy, and the position where the hub is screwed to the rotating shaft is aligned with the hub's rotating shaft. Since the hub is located at the center in the longitudinal direction, a hub that rotates correctly at right angles to the axis of rotation of the rotary disk with little tilting of the rotary disk can be obtained, and the reliability of a detector etc. to which this hub is applied is significantly improved.

[Brief explanation of the drawing]

FIG. 1 is a sectional side view of the upper half of an embodiment of the present invention, and FIG. 2 is an explanatory diagram of a conventional example. 1... Rotating disk, 2, 2a... Hub, 3...
... Set screw, 4 ... Rotating shaft, 5 ... Screw hole.

Claims (1)

[Scope of Claim for Utility Model Registration] In a hub that has a step in the outer diameter direction, a rotating disk is fixed to the side surface of the step, the inner circumferential surface of the disk is fitted onto the outer circumferential surface of the rotating shaft, and the hub is screwed onto the rotating shaft. A recessed hole is provided in the center of the inner circumferential surface to be mated, and a threaded hole is drilled from the outer circumferential surface toward the rotating shaft. A rotary disk hub that is located approximately at the center of its length.