JP2000240727A - Automatic aligning device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dispense with manual aligning work by fitting a vibration system to a rotor or a rotary shaft thereof, and displacing the vibration system in a direction for correcting the displacement of the center of gravity of the rotor in response to the vibration of the rotor or the rotary shaft. SOLUTION: A moving body 5 forming a vibration system is fitted to a rail 4 of a holding plate 3 on a rotor 1, and a counter mass 6 is fitted to an opposite side of the moving body 5 in relation to a rotary shaft 2. The moving body 5 is formed of a vibration system having a resonant frequency of at least one rotating cycle of the rotor 1, and the rotor 1 is displaced or moved in a direction for correcting the displacement of the center of gravity of the rotor 1 in response to the vibration of the rotary shaft 2. With this automatic movement, the aligning device is statically held after the aligning is concluded, and the generation of vibration at the time of rotating the rotor 1 is thereby restricted. With this structure, manual aligning work is dispensed with and labor cost is lowered, and accurate aligning can be performed in the condition that the rotor 1 is fitted to a structure of equipment.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic alignment device for automatically aligning a rotating body applied to various electric appliances and the like.

[0002]

2. Description of the Related Art Conventionally, in a drive mechanism used for driving a photosensitive member of an image forming apparatus and a drive of a machine tool, etc., vibrations due to the drive are suppressed to a minimum in order to prevent occurrence of image disturbance. There is a need to. In particular, a rotating body having a large inertia, such as a driving motor or a flywheel, applies a vibrating force to a substrate on which the rotating body is mounted in one rotation cycle to vibrate the structure if the center of gravity and the rotation center do not match. Further, when the rotation axis is shaken, the drive system also generates vibration of one rotation cycle. Further, when the rotation axis is perpendicular to the direction of gravity, the torque required for rotation changes depending on the position of the center of gravity of the rotating body, and vibrations of one rotation cycle are applied to the structure and the drive system. In this case, in order to make the center of gravity coincide with the rotation axis, a motor or a flywheel is created with high accuracy, or after the creation, a heavy object is manually attached and adjusted.

[0003]

However, in the conventional method for adjusting the rotating body, if the rotating body is produced with high accuracy, the production cost is increased, and there is a certain amount of variation, and the centering work is still required. There was a problem. In addition, manual adjustment of the center of gravity increases the man-hour cost, and varies depending on the worker. In addition, there is a problem that even when the center can be aligned with a single product, the center of gravity moves depending on how the devices are attached to the structure.

The present invention solves the above-mentioned problems, and eliminates the need for manual alignment work, reduces labor costs, and reduces processing costs for the rotating body. It is an object of the present invention to provide an automatic centering device capable of performing centering with high accuracy while being attached to a similar type of structure.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to an automatic alignment device for automatically aligning a rotating body, wherein a vibration system having a resonance frequency of at least one rotation cycle of the rotating body is provided. Alternatively, the vibration system is attached to the rotating shaft, and the vibration system is configured to be displaced in a direction for correcting a shift of the center of gravity of the rotating body according to the vibration of the rotating body or the rotating shaft.

In this configuration, the vibration system attached to the rotating body or the rotating shaft is automatically displaced in a direction for correcting the displacement of the center of gravity of the rotating body in accordance with the vibration, so that manual alignment work is not required. In addition, since the rotating body does not need to be manufactured with high precision, the processing cost is reduced. Furthermore, centering can be performed in a state where the rotating body is attached to the structure of the equipment, and the accuracy of centering is improved.

Further, in the above, the displacement of the center of gravity can be corrected by moving the vibration system itself. Thereby, self-alignment can be performed with a relatively simple mechanism.

Further, a rack for movably mounting a vibration system is provided on the rotating body or the rotating shaft, and the vibration system is provided with claws capable of engaging with teeth of the rack, and the vibration system vibrates. Sometimes, the engagement between the pawl and the teeth of the rack is temporarily released, and the vibration system can be moved. Thus, the vibration system can be reliably moved with a simple configuration, and automatic alignment can be performed.

Further, there may be a plurality of moving vibration systems. The moving path of the moving vibration system may be the normal direction or the circumferential direction of the rotating body. This facilitates three-dimensional self-alignment.

[0010] The moving path of the moving vibration system may be spiral. This gives 2
Fine self-alignment in a three-dimensional plane becomes possible.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an automatic centering device according to an embodiment of the present invention will be described with reference to the drawings. FIG.
(A) and (b) show a self-aligning device for a rotating body according to a first embodiment, in which a rotating body 1 has a disk-like shape such as a flywheel provided in a drive system for driving a photoconductor of an image forming apparatus. Things. The rotating body 1 is rotatably provided around a rotating shaft 2 to which a driving force is applied from a driving source (not shown). The rotating body 1 is provided with a rail 4 (path) on a holding plate 3 extending in the normal direction including the rotating shaft 2, and a moving body 5 forming a vibration system is attached to the rail 4. The opposite mass 6 is attached to the opposite side with respect to 2. The moving body 5 forms a vibration system having a resonance frequency of at least one rotation cycle of the rotating body 1, and can be displaced in a direction for correcting a shift of the center of gravity of the rotating body 1 according to the vibration of the rotating body 1 or the rotating shaft 2. It is configured as follows.

The operation of this self-centering device will be described. The moving body 5 is automatically displaced or moved in a direction to correct the displacement of the center of gravity in accordance with the vibration of the rotating body 1 (specific structure of the moving body 5). An example will be described later).
Vibration is suppressed when the rotating body 1 rotates. By performing alignment in this way, manual alignment work is not required, labor costs are reduced, and alignment can be performed with the rotating body 1 attached to the structure of the equipment. Accurate alignment can be performed. In addition, the mechanism becomes relatively simple, and the processing cost can be reduced.

FIGS. 2A and 2B show an automatic centering device according to a second embodiment. In this embodiment, the rail 4 is provided on the peripheral wall surface of the rotating body 1, and the moving body 5 is movably attached thereto. The moving direction of the moving body 5 is indicated by an arrow. According to this configuration, self-alignment can be appropriately performed with respect to weight variation in the rotation direction of the rotating body 1.

FIGS. 3A and 3B show an automatic centering device according to a third embodiment. In the present embodiment, a rail 4 is provided spirally around a rotation shaft 2 on the side surface of the rotating body 1, and a moving body 5 is movably mounted thereon. According to this configuration, since the moving body 5 can be finely moved in a two-dimensional plane, it is possible to accurately perform automatic alignment.

FIGS. 4A and 4B show an automatic centering device according to a fourth embodiment. In this embodiment, a plurality of rails 4 are provided along the axial direction on the peripheral wall surface of the rotating body 1, and moving bodies 5 and 5 ′ having different masses are movably attached to them. The number of teeth of the rail 4 is different.
According to the configuration of the present embodiment, the plurality of moving bodies 5 and 5 'having different masses are located side by side in the direction of the rotation axis, so that fine adjustment for the weight variation in the axis direction is possible.

FIGS. 5A, 5B and 5C show specific examples of the structure of the moving body 5 in the first embodiment. The moving body 5 is a rail 4 provided on the rotating body 1 (such as FIG. 1) in the normal direction.
This moving body 5 is movably engaged and held, and a mass 51 of the moving body 5 is locked inside a sheath by a spring 52, and a roller-shaped rotating body 53 (claw of a vibration system) is projected and supported by the mass 51. This roller-shaped rotating body 53 is provided with rack teeth 4 provided on the rail 4.
1 is in a state of being engaged in a steady state, and when vibration occurs during the rotating operation of the rotating body 1, the engagement is released and the moving body 5 is disengaged.
Can move in the direction in which the centrifugal force is applied.

The operation of the above configuration will be described. When the center of gravity of the rotating body 1 does not coincide with the center of rotation, the rotating body 1 vibrates in one rotation cycle, so that the moving body 5 supported via the spring 52 Vibration occurs as indicated by the arrow in FIG. 5A, and the engagement of the roller-shaped rotating body 53 with the rack teeth 41 is released.
As shown by the arrow in FIG. 4C, the roller-shaped rotating body 53 moves in the direction of the centrifugal force applied to the moving body 5 by the rotation of the rotating body 1, and is brought into a state of engaging with the adjacent rack teeth 41.
In this way, the moving body 5 moves in response to the vibration, and when the center of gravity of the rotating body 1 coincides with the center of rotation, no vibration occurs and the moving body 5 does not move. Thus, the self-aligning operation is performed.

FIG. 6 shows a modification of the moving body shown in FIG. In this example, a gear 55 urged by a spiral spring 54 is provided on the moving body 5, and the gear 55 meshes with the rack teeth 41. With this configuration, the moving body 5 can be smoothly moved during vibration. FIG. 7 shows still another example of the moving body 5. In this example, the fixing screw 56 is provided on the moving body 5. In a state where the aligning operation is completed, the moving body 5 is fixed to the rail 4 by tightening the fixing screw 56, so that the subsequent operation can be stabilized.

FIGS. 8 and 9 show an automatic centering device according to a fifth embodiment. In each of the above embodiments, the alignment is performed by moving any of the moving bodies 5 forming the vibration system. However, the following embodiments detect the amplitude of the vibration of the vibration system, and The displacement of the center of gravity of the rotating body 1 can be corrected without moving the vibration system.
In this device, a vibration system 50 is attached to the rotating body 1, and a giant magnetostrictive element 60 is provided between the rotating body 1 and the rotating shaft 2 in two directions like an arm. The automatic alignment of the rotating body 1 is performed.

More specifically, in the vibration system 50, the mass 51 is held so as to vibrate by a spring 52, the amplitude of the vibration is detected by a photo sensor 61, and a control device 62 is controlled by a magnetic field generating means based on the signal. A certain two coils 63 are excited. The giant magnetostrictive element 60 expands and contracts due to the magnetic field generated by the excitation of the coil 63, whereby the rotating body 1 is finely adjusted two-dimensionally with respect to the rotating shaft 2, thereby performing automatic alignment. The control device 62 may excite the coil 63 with reference to data prepared in a table in advance based on the received signal. In addition, the method of detecting the amplitude of the vibration system 50 includes a method of generating a surrounding current with a coil, a method of using a piezoelectric element, and the like, in addition to checking the position of the mass 51 with the photo sensor 61.

It should be noted that the present invention is not limited to the configuration of the above embodiment, and various modifications are possible. For example, in the above, the automatic alignment device of the rotating body in the drive system such as the photosensitive member of the image forming apparatus has been described, but an alignment mechanism may be attached to the rotating shaft,
Further, the present invention can be similarly applied to self-alignment of a rotating body such as a machine tool.

[0022]

As described above, according to the present invention, the self-aligning action can be obtained by displacing the vibration system attached to the rotating body in a direction for correcting the displacement of the center of gravity of the rotating body in accordance with the vibration. The need for manual alignment work is eliminated,
In addition, since the rotating body does not need to be manufactured with high accuracy, the processing cost can be reduced. In addition, centering can be performed with high accuracy even in a state where the rotating body is attached to the structure of the equipment. Furthermore, by correcting the displacement of the center of gravity by moving the vibration system itself,
Self-alignment can be performed with a simple mechanism.

[Brief description of the drawings]

FIGS. 1A and 1B are a front view and a cross-sectional view of a self-aligning device according to a first embodiment of the present invention.

FIGS. 2A and 2B are a front view and a cross-sectional view of a self-aligning device according to a second embodiment of the present invention.

FIGS. 3A and 3B are a front view and a cross-sectional view of a self-aligning device according to a third embodiment of the present invention.

FIGS. 4A and 4B are a front view and a cross-sectional view of a self-aligning device according to a fourth embodiment of the present invention.

FIGS. 5A, 5B, and 5C are a cross-sectional view, a vertical cross-sectional view, and a front view of rack teeth of the moving body of the self-aligning device according to the first embodiment, respectively.

FIG. 6 is a longitudinal sectional view showing a modification of the moving object shown in FIG. 5;

FIG. 7 is a longitudinal sectional view showing still another example of the moving body shown in FIG. 5;

FIG. 8 is a front view of a self-aligning device according to a fifth embodiment.

FIG. 9 is a longitudinal sectional view of the self-aligning device according to the embodiment.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 rotating body 2 rotating shaft 4 rail (path) 41 rack teeth 5 moving body (vibration system) 51 mass 52 spring 53 roller-like rotating body (claw of vibration system)

Claims (6)

[Claims] An automatic centering device for automatically aligning a rotating body, wherein a vibration system having a resonance frequency of at least one rotation cycle of the rotating body is attached to the rotating body or its rotating shaft, and the vibration system is the rotating body or the rotating body. An automatic centering apparatus characterized in that it is configured to be displaced in a direction for correcting a shift of the center of gravity of the rotating body according to vibration of a rotating shaft. 2. The self-centering device according to claim 1, wherein the displacement of the center of gravity is corrected by moving the vibration system itself. 3. A rack for movably mounting the vibrating system is provided on the rotating body or the rotating shaft, and the vibrating system is provided with claws capable of engaging with teeth of the rack. The self-centering device according to claim 1, wherein when the vibration system vibrates, the engagement between the claw and the teeth of the rack is temporarily released, and the vibration system moves. 4. The self-centering device according to claim 2, wherein there are a plurality of moving vibration systems. 5. The moving path of the moving vibration system is a normal direction or a circumferential direction of the rotating body.
5. The self-aligning device according to 2. 6. The self-centering device according to claim 2, wherein the moving path of the moving vibration system is spiral.