JPH0956129A - Manufacture of polygon mirror motor and polygon mirror motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the generation of deflection or the like at the time of high-speed rotation with inexpensive constitution by forming constitution including the process of adjusting the deflection of a laser beam by correcting the inclination of a polygon mirror while monitoring a reflected laser beam. SOLUTION: A lubricant sheet and a bearing 2 are built in the recessed part of an optical box and fixed by press-in or the like at the time of assembling and after that, a stator base on which a drive circuit and a stator coil 3a are mounted is fastened in a threaded hole 1C by a screw 4 for fixing. Next, after a shaft body 7 in the state that a polygon mirror 6 is fixed to a permanent magnet 5 is inserted into a fixed bearing 2, the upper end of the shaft body 7 is inserted into one in which a bearing 8 is fixed to a bearing holding plate 9 and then is temporarily fixed by a screw 10 to the shaping part 1S of the optical box 1. Successively, the screw 10 is completely fixed in the position of the best condition of a deflection by very finely moving the holding plate 9 back and forth and left and right while rotating a motor and actually applying a laser beam to the polygon mirror 6. As a result, the generation of deflection or the like at the time of high-speed operation can be prevented with inexpensive constitution.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a polygon mirror motor and a polygon mirror motor, for example, a polygon mirror motor used when scanning a laser beam in a laser beam printer, a copying machine, various scanner devices and the like. Related to the improvement of.

[0002]

2. Description of the Related Art Conventionally, a polygon mirror motor is used when scanning a laser beam for recording and reproduction in a laser beam printer, a copying machine or the like. FIG. 3 shows a typical conventional polygon mirror motor. In this figure, the conventional polygon mirror motor is
It is a so-called single-support type, and has a structure in which a polygon mirror is installed on the motor output shaft side. That is, at the center of the optical box 101, there is provided a through hole for fixing the member 112 having the bearing 119 having a double row of balls built therein at a predetermined position. By fixing the shaft body 113 held by the bearing 119 in the radial direction and the thrust direction, the shaft body 113 is rotatably held and in a one-sided supported state. Also, the member 11
Reference numeral 2 guides the guide holes formed in the stator base 103 so that the stator coil 3a and the shaft body 113 are concentric, while the screw 104 fixes the stator base 103 on the optical box 101. It is configured.

On the other hand, a multi-pole magnetized permanent magnet 105, which is a rotor unit, is fixed to the shaft body 113 on the outer peripheral surface thereof. A flange member 114 for fixing the polygon mirror 106 in contact with the upper surface thereof is fixed. In addition, the polygon mirror 106 is held in an immovable state by a spring member 115, one end of which engages with a groove formed in the shaft 113 and the other end of which is pressed against the upper surface of the polygon mirror 106. Body 11
The squareness with respect to 3 is accurately held and then brought into contact with the fixed flange member 114,
It is configured to ensure the parallelism of the reflecting surface of the polygon mirror 106 to the shaft body 113.

However, in the conventional polygon mirror motor, since the shaft body is configured to support one side as described above, the inclination accuracy of the polygon mirror (that is, the parallelism with respect to the central axis of rotation). It is necessary to make the precision of each part strict for the management of. This is because if a motor with a large tilt or shake of the polygon mirror is used as it is in a printer device, it will appear as a deterioration in printer image quality. Therefore, the tilt and shake prevention of the polygon mirror are necessary priority items.

If the precision of the parts is increased more than necessary, the cost will inevitably increase, which is not preferable. Therefore, if the structure is such that even if the mirror is slightly tilted, it can be corrected in the final step, and the component accuracy can be improved with normal accuracy. On the other hand, the accuracy of the optical box itself needs to be sufficiently controlled, and the processing and assembling jigs and tools for the component parts are very complicated, which is disadvantageous in terms of cost.

Further, since the polygon mirror is directly fixed to the shaft 113 which is supported on one side, if the dynamic balance is not within the allowable range, the shaft tilts, shakes and the like become large, and unexpected vibration occurs. There was also a problem that occurred.

Therefore, the polygon mirror motor of the present invention has been made in view of the above problems, and in order to control the inclination accuracy of the polygon mirror, the dimensional accuracy, the shape accuracy, etc. of each component including the optical box are controlled. Polygon mirror motor manufacturing method and polygon which are not necessarily managed sufficiently and can be constructed at low cost by eliminating the need for processing / assembling jigs and tools for each component and minimizing the number of jigs The purpose is to provide a mirror motor.

[0007]

In order to solve the above-mentioned problems and to achieve the object, according to the present invention, a shaft body to which a polygon mirror is fixed is axially supported in both supporting states, and the polygon mirror is continuously connected. A method of manufacturing a polygon mirror motor that rotates at high speed, wherein the rotor body provided integrally with the shaft body has a pedestal surface perpendicular to a rotation center axis line of the shaft body and the rotor magnet. And a first bearing and a magnetic field generating means for generating a rotating magnetic field for the rotor magnet are fixed to the body of the polygon mirror motor, and the first bearing is fixed to the first bearing. Inserting one end of the shaft body, mounting the polygon mirror on the pedestal surface, and fitting a cap means for holding the polygon mirror to the shaft body,
A step of temporarily fixing a bearing support member, which fixes a second bearing inserted at the other end of the shaft body, to the main body; and a step of rotating the shaft body so that a laser beam is applied to the reflection surface of the polygon mirror. And finely adjusting the fixed position of the bearing support member while monitoring the reflected laser light, correcting the inclination of the polygon mirror to an appropriate position and adjusting the deflection of the laser beam to obtain a finished product. Is characterized by.

In addition, one end of the shaft body is inserted into the first bearing, the polygon mirror is mounted on the pedestal surface, and a lid body is attached to hold the polygon mirror. A second step of inserting a biasing member into the shaft, and a radial ball bearing inserted into the other end of the shaft
The finished product is obtained through a step of temporarily fixing the bearing support member to which the bearing is fixed to the main body.

Further, according to the polygon mirror motor of the present invention, the polygon mirror motor is a polygon mirror motor which supports a shaft having a fixed polygon mirror in both supported states and rotates the polygon mirror continuously at a high speed. The shaft body and the rotor magnet are integrally pre-configured so that the pedestal surface of the rotor magnet integrally provided is at right angles to the rotation center axis of the shaft body, and 1
Fixing the bearing and the magnetic field generating means for generating a rotating magnetic field to the rotor magnet, inserting one end of the shaft into the first bearing, and mounting the polygon mirror on the pedestal surface. A bearing support member for fixing the second bearing, which is inserted into the other end of the shaft body, to the main body by fitting a cap means for holding the shaft body in the contact state. Temporarily fixing, irradiating a laser beam on the reflecting surface of the polygon mirror while rotating the shaft, finely adjusting the fixing position of the bearing support member while monitoring the reflected laser light, and tilting the polygon mirror. Is adjusted to an appropriate position and the deflection of the laser beam is adjusted.

Further, one end of the shaft body is inserted into the first bearing, and the polygon mirror is mounted on the pedestal surface and urged by the lid body to keep the polygon mirror in contact. A member is inserted into the shaft body, and a bearing support member having a second bearing, which is a radial ball bearing inserted into the other end of the shaft body, is fixed to the main body. It is characterized by getting.

Further, the first bearing is characterized by being constituted by an oil-impregnated sintered bearing and a sheet body in order to receive loads in the radial direction and the thrust direction of the shaft body.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings. First, FIG. 1 (a) shows the first
FIG. 9 is a central cross-sectional view cut away along a shaft body 7 of the polygon mirror motor according to the embodiment of the present invention.

In the figure, a recess 1a is formed in the center of an optical box 1 for accommodating a bearing 2 made of an oil-containing sintered material or the like and a lubricating sheet 12 made of a resin sheet material having lubricity. And the recess 1a as shown
By incorporating the bearing 2 and the lubricating sheet 12 therein, one end of the shaft body 7 is supported by receiving the load of the shaft body 7 in the radial direction and the thrust direction.

Further, the left and right wall surfaces of the optical box 1 have a shape portion 1S.
The holding plate 9 in which the bearing 8 formed of the oil-impregnated sintered material or the like is previously fixed by caulking or the like is fixed to the shape portion 1S by the screw 10 in the same manner as described above. The shaft 7 is inserted into the shaft 8a, and then fixed to the optical box 10 with the screw 10 to support the other end of the shaft.

Further, the stator base 3 on which the stator coil 3a is mounted is formed so as to be concentric with the shaft body 7 and is fixed on the optical box 1 by the screw 4.

On the other hand, a multi-pole magnetized permanent magnet 5 which is a rotor unit is fixed to the shaft body 7 in advance. The permanent magnet 5 is fixed to the shaft body 7 and then on the basis of the axis. By lathe-processing the central part and the pedestal part of the polygon mirror 6, a perpendicularity with respect to the shaft is secured.

The oil leak cap 11 having the fitting hole 11a for fixing the polygon mirror 6 in the abutting state is subsequently press-fitted on the pedestal surface of the permanent magnet fixed as described above. Fixing of polygon mirror 6 and bearing 8
Is also configured to prevent oil leakage included in the.

With the above construction, both ends of the shaft body 7 are supported, so that shaft runout is prevented.

Next, FIG. 2 is a three-dimensional exploded view of the first embodiment, and is a drawing that best represents the features of the present invention.

In this figure, as the assembling procedure, first, the lubricating sheet 12 and the bearing 2 are built in the recess 1a of the optical box 1 and fixed by press fitting or the like. Next, the stator base 3 on which the drive circuit and the stator coil 3a are mounted is tightened and fixed in the screw hole portion 1C of the optical box 1 by using the screw 4. Next, the shaft body 7 in which the polygon mirror 6 is previously fixed to the permanent magnet 5 is inserted into the fixed bearing 2. Next, after inserting the upper end of the shaft body 7 into the bearing holding plate 9 in which the bearing 8 is fixed in advance, the upper end of the shaft body 7 is inserted. Temporarily fixed to
Bring it to the completed state before adjustment.

Subsequently, in order to adjust the deflection of the laser beam, the holding plate 9 is finely moved forward, backward, left and right while actually irradiating the polygon mirror 6 with the laser beam while rotating the motor, so that the optimum deflection condition is obtained. Fix the screw 10 completely in position.

As a result of the above construction, each unit of the motor is directly assembled to the optical box, so that the number of parts can be reduced and the tilt accuracy of the polygon mirror can be reduced without using parts accuracy or a special assembly jig. Finely move the holding plate 9 during final adjustment,
By making optical adjustments, it will be possible to reduce costs considerably.

Further, conventionally, a special tool was used for adhesion in order to prevent the shaft body 113 from inclining with respect to the reference plane of the member 112, but such a special tool is unnecessary. Further, since it is not necessary to make the precision of the parts severe, the assembly and processing cost can be reduced. Further, since the polygon mirror 6 can be positioned with reference to the pedestal surface of the permanent magnet 5 which is a rotor magnet, tilt shake can be reduced.

Since each of the bearings 2 and 8 uses a general sintered oilless bearing, the shaft diameter of the shaft body 7 is minimized in order to reduce the rotational friction loss. The processing was minimized to make it more cost effective.

FIG. 1 (b) is a cross-sectional view of an essential part of a modification of the first embodiment, in which the above-mentioned sintered bearing 2,
In the case where 8 is uncertain in terms of reliability, a configuration example in which the ball bearing 18 is used instead of the bearing 8 is shown. In this case, the oil leak cap 11 can be omitted, and instead the polygon mirror 6 is fixed by abutting on the permanent magnet with the ring-shaped mirror retainer 110 and the preload spring 20 provided.

As described above, in order to suppress the inclination of the polygon mirror to the utmost limit, the polygon mirror is positioned closer to the center side, and the intermediate step of assembling the parts and the motor is omitted, so that the optical box (or the main body) is directly incorporated. By doing so, the assembling becomes easy, and the cost effect becomes great.

As described above, since the shaft body to which the polygon mirror is fixed is supported by both supporting states, shaft runout can be prevented, and the second bearing to be inserted into the other end of the shaft body is fixed to the bearing. With the support member temporarily fixed to the main body, while rotating the shaft, the laser beam is applied to the reflective surface of the polygon mirror and the fixed position of the bearing support member is finely adjusted while monitoring, so assembly is simple. Can be converted.

[0028]

As described above, according to the present invention,
In order to control the tilt accuracy of the polygon mirror, the dimensional accuracy and shape accuracy of each component including the optical box are not always sufficiently controlled, and the processing and assembly jigs and tools for each component are unnecessary or minimized and inexpensive. It is possible to provide a polygon mirror motor manufacturing method and a polygon mirror motor which can be configured as described above and in which there is no fear of occurrence of shake or the like during high-speed rotation.

[0029]

[Brief description of drawings]

FIG. 1A is a central sectional view of a polygon mirror motor according to a first embodiment. (B) It is sectional drawing of the principal part of the modification of the polygon mirror motor of 1st Example.

FIG. 2 is a three-dimensional exploded view of the polygon mirror motor of the first embodiment.

FIG. 3 is a sectional view of a main part of a conventional polygon mirror motor.

[Explanation of symbols] 1 Optical box 2 Bearing 3 Stator base 4 Screw 5 Permanent magnet 6 Polygon mirror 7 Shaft body 8 Bearing 9 Bearing holding plate 10 Screw 11 Cap

Claims (5)

[Claims] 1. A method of manufacturing a polygon mirror motor in which a shaft, to which a polygon mirror is fixed, is axially supported in both supported states, and the polygon mirror is continuously rotated at high speed, the rotor magnet being provided integrally with the shaft. Combining the shaft body and the rotor magnet so that the pedestal surface of the rotor is at right angles to the rotation center axis of the shaft body; a first bearing for the main body of the polygon mirror motor; and the rotor. Fixing a magnetic field generating means for generating a rotating magnetic field to the magnet, and inserting one end of the shaft body into the first bearing, and mounting the polygon mirror on the pedestal surface,
And a step of fitting a cap means for holding the contact state to the shaft body, and a bearing support member fixed to a second bearing inserted into the other end of the shaft body with respect to the main body. A step of temporarily fixing, and a laser beam is applied to the reflecting surface of the polygon mirror while rotating the shaft body, and the fixing position of the bearing support member is finely adjusted while monitoring the reflected laser light. A method for manufacturing a polygon mirror motor, which comprises the steps of correcting the tilt of the laser beam to an appropriate position and adjusting the deflection of the laser beam, and obtaining a finished product through the steps. 2. A lid body for inserting one end of the shaft body into the first bearing, mounting the polygon mirror on the pedestal surface, and holding the polygon mirror in a contact state.
A step of inserting a biasing member into the shaft body, and a step of temporarily fixing to the main body a bearing support member to which a second bearing, which is a radial ball bearing inserted into the other end of the shaft body, is fixed. The method for manufacturing a polygon mirror motor according to claim 1, wherein a finished product is obtained through 3. A pedestal surface of a rotor magnet provided integrally with the shaft body, which is a polygon mirror motor for rotatably supporting a shaft body having a fixed polygon mirror in a supported state and rotating the polygon mirror continuously at a high speed. And the rotor magnet are integrally pre-configured so that is perpendicular to the center axis of rotation of the shaft body, and the first bearing with respect to the main body of the polygon mirror motor and the rotation with respect to the rotor magnet. The magnetic field generating means for generating a magnetic field is fixed, one end of the shaft body is inserted into the first bearing, and the polygon mirror is mounted on the pedestal surface and held in a contact state. A cap means for fitting the shaft body, and a second bearing inserted into the other end of the shaft body to which a second bearing is fixed is temporarily fixed to the main body to rotate the shaft body. Laser while letting Irradiate the reflecting surface of the polygon mirror, finely adjust the fixed position of the bearing support member while monitoring the reflected laser light, correct the tilt of the polygon mirror to an appropriate position, and deflect the laser beam. A polygon mirror motor characterized by being adjusted. 4. The one end of the shaft body is inserted into the first bearing, and the polygon mirror is mounted on the pedestal surface and biased with a lid body to hold the polygon mirror. A member is inserted into the shaft body, and a bearing support member having a second bearing, which is a radial ball bearing inserted into the other end of the shaft body, is fixed to the main body. The polygon mirror motor according to claim 3, wherein the polygon mirror motor is obtained. 5. The first bearing is composed of an oil-impregnated sintered bearing and a sheet body to receive a load in a radial direction and a thrust direction of the shaft body.
Alternatively, the polygon mirror motor according to claim 4.