JPS6056940B2 - Rotating body center of gravity position adjustment device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a gravity center position adjusting device for adjusting the gravity center position of a rotating body such as a mirror used in optical equipment such as an electrophotographic copying machine.

2. Description of the Related Art Document production devices such as electrophotographic copying machines optically read a document by exposing and scanning the surface of the document.

FIGS. 1 and 2 show a mirror drive device for use in copying machines and the like, which was previously proposed by the applicant. Mirror 1 is support member 2
A rotation shaft 3 is provided protruding from both ends of the support member 2, and an arc-shaped motor 5 is connected to one end of the support member 2 via an arm 4.

The arc-shaped motor 5 includes an arc-shaped stator 6 and an arc-shaped movable element 7, and the centers of curvature of the stator 6 and the movable element 7 are designed to coincide with the center of rotation o of the mirror 1 and the like. Stator 6
is composed of an outer yoke portion 8, an inner yoke portion 9, an end yoke portion 10, and a permanent magnet 11 fixed to the inner peripheral surface of the outer yoke portion 8.

The movable element 7 includes a hollow bobbin 12 that is disposed in the gap between the inner yoke part 9 and the permanent magnet 11 and is movable along the inner yoke part 9, and a coil 13 wound around the hollow bobbin 12. The movable element 7 is then
rotates. A plate-shaped electromagnet 14 is arranged at a predetermined interval on the side facing the stator 6 (see Fig. 2).
The range of rotation of the movable element 7 is regulated by the distance between the stator 6 and the electromagnet 14.

Reference numeral 15 denotes an abutment plate provided on the side of the arm 4 facing the electromagnet 14.

The electromagnet 14 has a function of holding a swinging member such as the mirror 1 and the support member 2 at its home position for a predetermined period of time for each exposure scan, and when no exposure scan is performed, the arc motor 5 is stopped. Rotating members such as the mirror 1 and the support member 2 are held at home positions by electromagnets 14. Therefore, if the mirror 1 reflects light from a light source installed in the copying machine and illuminates the document surface, and the arc-shaped motor 5 rotates the mirror 1, the light reflected from the mirror 1 can be used to expose and scan the document surface. It has become a mechanism that can do this.

When rotating the mirror 1, the rotation state of the mirror 1 is monitored using an angle detector (not shown), and the rotational state of the mirror 1 is monitored based on a predetermined target value of the rotation pattern and the mirror rotation obtained from the angle detector. The angle is compared from time to time, and the deviation is added to a control device (not shown) to control the current value flowing through the coil 13 of the arc-shaped motor 5. In order to control the rotation of this mirror with high precision, its control characteristics must be optimized.

By the way, the rotating part of this device is the mirror 1.
, a support member 2, a rotation shaft 3, an arm movable element 7, and the like.
When these rotating parts are regarded as a rotating body whose center of rotation is O, the center of gravity G of the rotating body generally does not coincide with the center of rotation 0, as shown in FIG. When the distance from the center of rotation 0 to the center of gravity G is r1 and the weight of the rotating body is W, the amount of unbalance due to gravity F is F=W-RcOsθ, and its value changes every moment according to the rotation angle θ. This change appears as a load fluctuation when the arc motor 5 rotates the mirror 1, and therefore, the rotation control of the mirror 1 becomes complicated. Therefore, in such a case, it is sufficient to perform a balancing operation of the rotating body using a center of gravity position adjusting device made of a weight member or the like so that the substantial center of gravity is located on the center of rotation. An object of the present invention is to provide a center of gravity position adjusting device that is simple in structure and operation.

In order to achieve this object, the present invention is mounted to a rotating body whose center of gravity is to be adjusted so as to be rotatable about the rotational center line of the rotating body, and which intersects the rotational center line. a rotation adjustment member having a sliding groove extending in the direction; a rotation adjustment member positioning means for positioning the rotation adjustment member; and a slide adjustment member slidably attached to the sliding groove. and a sliding adjustment member positioning means for positioning the sliding adjustment member.

Next, embodiments of the present invention will be described with reference to the drawings.

4 to 6 are diagrams showing a first embodiment of the present invention. The center of gravity position adjustment device mainly includes a holding member 16, a rotation adjustment member 17, and a sliding adjustment member 18.

An annular protrusion 19 for holding the rotation adjustment member 17 is provided on the front outer periphery of the holding member 16, and a hole 20 through which the rotation shaft 3 passes is formed in the center. As shown in FIG. 6, a screw hole 21 is bored in at least one part of the annular protrusion 19 from the outer periphery toward the inner periphery, into which a screw 22 for positioning the rotation adjustment member 17 is screwed. . 2
3 is a screw hole for attaching the holding member 16 to the end plate 24 of the mirror drive device, and as shown in FIG.
The holding member 16 is fixed to the end plate 24 by a countersunk screw 25 screwed into the end plate 3 .

Reference numeral 26 is a rotation start mark provided at a suitable position on the outer circumferential surface, and it can be made into a scale shape if necessary.

The rotation adjustment member 17 is designed to be point symmetrical so that the center of gravity does not change even when rotated, that is, is located on the rotation center line.

A cylindrical portion 27 that fits into the annular protrusion 19 of the holding member 16 is provided at the center of the rear surface, and an annular groove 28 into which the tip of the screw 22 fits is formed on the outer periphery of the cylindrical portion 27. (See Figure 5). A hole 29 through which the rotating shaft 3 passes is provided in the center, and a sliding groove 30 is formed across the front opening of the hole 29. A screw hole 31 is provided near the slide groove 30, and a presser screw 32 for positioning the slide adjustment member 18 is screwed into the screw hole 31. Further, near the sliding groove 30, there is a sliding scale 33 as a guide for adjusting the sliding adjustment member 18, and on the outer periphery there is a matching line that is aligned with the rotation start mark 26 of the support member 16 before adjustment. 34 are provided respectively. Sliding adjustment member 18
has a shape that can be slid by fitting into the sliding groove 30 of the rotation adjustment member 17, and an elongated hole 35 is formed in the center so that the rotation shaft 3 can be slid therethrough. There is.

A matching line 36 facing the sliding scale 33 is provided on the front surface of the sliding adjusting member 18 . For example, in order to adjust the balance of the mirror drive device described above, first, the center of gravity position adjustment device is attached to the end plate 24 of the mirror drive device so that the rotation shaft 3 passes through it.

This state is shown in FIG. 4, where the alignment line 34 is aligned with the rotation start mark 26, and the alignment line 36 is aligned with the zero line of the sliding scale 33, and the sliding adjustment member 18 is adjusted to rotate. It is fixed at the center position of the member 17. By attaching it to the end plate 24 in this way, the center of the rotation adjustment member 17 is aligned with the rotation center of the mirror drive device, and the slide adjustment member 18 can be slid along a straight line passing through the rotation center. A rotation adjustment member 17 and a slide adjustment member 18 are arranged at. Next, the rotating body of the mirror drive device (mirror 1, support member 2, rotation shaft 3, arm male mover 7) with the center of gravity position adjustment device attached.
etc.) and the unbalance direction are detected by appropriate means.

The amount of unbalance is determined from a calculation formula by attaching a test weight with a known mass at a position a predetermined distance away from the rotation center and measuring the displacement angle of the rotating body due to the attachment. Furthermore, the direction of unbalance can be determined by the inclination of the stationary rotating body. Once the unbalance amount and unbalance direction of the rotating body are known, loosen the screw 22 and rotate the rotation adjustment member 17 so that the sliding groove 30 matches the unbalance direction, and when it reaches that position, tighten the screw 22 and rotate it. The adjustment member 17 is positioned.

Next, loosen the holding screw 32 and move the sliding adjustment member 18 along the sliding groove 30 by a distance corresponding to the amount of unbalance on the sliding scale 3.
3, and then fix the sliding adjustment member 18 again with the holding screw 32. In this embodiment, the rotation adjustment member 17 is provided with a sliding groove 30, along which the sliding adjustment member 18 is slid. It is also possible to form a groove in 18 into which a protrusion fits, and to move the sliding adjustment member 18 along the protrusion.

FIGS. 7 and 8 are diagrams showing a second embodiment of the present invention.

In the first embodiment, the rotation adjustment member 17 and the sliding adjustment member 18 are separate bodies, and a combination of the two constitutes a center of gravity position adjustment device, but the center of gravity position adjustment device 37 of this embodiment The adjustment member and the sliding adjustment member are integrated. That is, a long hole 35 through which the rotation shaft 3 passes is formed in the center of the center of gravity position adjustment device 37, and a matching line 34 is provided on the outer periphery. On the front surface of the holding member 16 that holds the center of gravity position adjustment device 37, rotation scales 38 including the rotation start mark 26 are provided radially, and sliding scales 33 are provided in a concentric arc shape. In the balancing operation, as in the first embodiment, first, the center of gravity position adjusting device 37 is rotated to direct its elongated hole 35 in the unbalanced direction, and then the center of gravity position adjusting device 37 is rotated to face the elongated hole 35 by a distance corresponding to the amount of unbalance. 35, and after the balance is completed, the center of gravity position adjusting device 37 may be fixed to the holding member 16 by suitable means such as adhesive. In the embodiment, the center of gravity position adjustment device was used to balance the rotating body, but it can also be used to intentionally deviate the center of gravity of the rotating body by a predetermined distance in a predetermined direction from the center of rotation. .

Moreover, it is also possible to attach this gravity center position adjustment device to a rotating body that rotates 360 degrees or more. The present invention has the above-described configuration, and can provide a gravity center position adjusting device that is simple in structure and operation, and can accurately adjust the gravity center position.

[Brief explanation of the drawing]

1 and 2 are a perspective view and a partially sectional side view of the mirror drive device, and FIG. 3 is an explanatory diagram showing the positional relationship between the center of rotation and the center of gravity of the rotating body of the mirror drive device, 4 to 6 are perspective views, sectional views, and exploded perspective views showing the installation state of the gravity center position adjusting device according to the first embodiment of the present invention, and FIGS. 7 and 8 are according to the second embodiment. There are a perspective view and a front view of the center of gravity position adjustment device. 1...Mirror, 2...Supporting member, 3...
...Rotation axis, 4...Arm, 7...
...Mover, 17...Rotation adjustment member, 18...
...Sliding adjustment member, 22...Screw, 32.
...Press screw, 37... Center of gravity position adjustment member, 0... Center of rotation, G... Center of gravity.

Claims (1)

[Claims] 1. A rotation adjustment device that is attached to a rotating body whose center of gravity is to be adjusted so as to be rotatable around its rotation center line, and has a sliding groove extending in a direction intersecting the rotation center line. a member, a rotation adjustment member positioning means for positioning the rotation adjustment member, a slide adjustment member slidably attached to a sliding groove of the rotation adjustment member, and a rotation adjustment member positioning means for positioning the rotation adjustment member; 1. A center-of-gravity position adjustment device for a rotating body, comprising: a sliding adjustment member positioning means for positioning; and a sliding adjustment member positioning means.