JPH05173086A - Method for locking rotary body for fluid bearing type light detector and locking member therefor - Google Patents

Abstract

PURPOSE:To easily fix a rotary body in a light deflector by holding the rotary body provided with a rotary mirror having large inertia in the light deflector by means of a modified screw and an elastic body so as not to move it. CONSTITUTION:Prior to the fixing of an upper cover 4, the modified screw 15 is inserted into a screw hole 19 formed on the cover 4 and its tip engaging part 20 is inserted into an engaging part 22. Then the cover 4 provided with the screw 15 is fixed on a case 3, an intermediate screw 18 fixed to a spindle 17 is screwed into the screw hold 19 formed on the cover 4 by turning a head screw 16, and in a state that the tip engaging part 20 of the spindle 17 is inserted into the engaging hole 22 of the elastic body 21 set up on the bottom of an upper opened hole 6b of the rotary mirror 6, the screw 18 fixed to the spindle 17 is screwed into the hole 19 by turning the screw 16. The engaging part 20 depresses the elastic body 21 to the bottom of the mirror 6 and holds the rotary body including the mirror 6 so as not to move it.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydrodynamic bearing type optical deflector, and more specifically, a method of preventing a shock to a rotating body generated during movement of the hydrodynamic bearing type optical deflector and a locking member thereof. Regarding

[0002]

2. Description of the Related Art A conventional hydrodynamic bearing type optical deflector of this type will be described. In FIG. 3, the rotating body of the hydrodynamic bearing type optical deflector is housed in a cavity formed by the case 3 and the upper lid 4. A groove 1a such as a herringbone is bored on the outer peripheral surface of the fixed shaft 1 fixed to the case 3, and a rotating body is mounted on the outer periphery of the fixed shaft 1. The rotating body has the following structure. A rotary mirror 6 having a U-shaped cross section is mounted on the upper surface of a hub 5 which is shrink-fitted to a hollow rotary shaft 2 in which the lower surface of an upper lid 4 is fitted around the outer circumference of a fixed shaft 1 with a predetermined gap. The substrate 8 is installed on the upper surface of the step portion 3a formed in the case 3, and the driving magnet 7 is fixed to the lower surface of the hub 5 so as to face the substrate 8. The coil 9 is fixed to the lower surface of the substrate 8 at a position facing the driving magnet 7. When a current is applied to the coil 9 placed in the magnetic field of the driving magnet 7, the hub 5 fixed to the driving magnet 7 together with the driving magnet 7 moves the outer periphery of the fixed shaft 1 along with the rotating mirror 6 and the hollow rotating shaft 2. Rotate. When the fluid is introduced into the gap between the hollow rotary shaft 2 and the fixed shaft 1, the fluid collides with a groove formed in the outer periphery of the fixed shaft 1, for example, the herringbone groove 1a, to generate dynamic pressure, and the hollow rotary shaft 2 floats. While rotating, it rotates with the rotating mirror 6 mounted on the hub 5. The beam enters through a beam hole 4a formed in the side surface of the case 3, is reflected by the mirror surface 6a of the rotating mirror, is emitted from the beam hole 4a, is deflected, and is disposed outside f.
The irradiation surface is scanned via a θ lens or the like. Hollow rotating shaft 2
By interposing the cushioning material 12 between the upper cover 4 and the lower surface of the upper lid 4, the displacement of the hollow rotary shaft 2 is prevented, and the impact given to the rotating body during transportation of the optical deflector is reduced.

[0003]

However, the conventional hydrodynamic bearing type optical deflector locking and fixing system of the rotating body has the following problems. When the inertia of the rotating mirror mounted on the hub provided by shrink fitting on the hollow rotating shaft is large, there is a problem that the position of the shrink fitting shifts due to the shock during transportation, and the position of the rotating mirror is changed. There is also a problem that when the buffer material is removed after the completion of transportation of the fluid dynamic bearing type optical deflector, a troublesome work such as removing the upper lid each time must be carried out.

[0004]

Therefore, the present invention provides a means for solving the above-mentioned problems. The means will be disclosed below. . A hydrodynamic bearing type in which a rotating body in which a rotating mirror 6 having a U-shaped cross section is mounted on a hub 5 mounted on a hollow rotating shaft 2 rotatably provided on the outer periphery of a fixed shaft 1 is housed in a cavity formed by an upper lid 4 and a case 3. In the optical deflector, the intermediate screw 18 formed in the intermediate portion of the screw shaft 17
Is screwed into the screw hole 19 of the upper lid 4, the end engaging portion 20 of the screw shaft 17 is engaged with the engaging hole 22 of the elastic body 21 placed on the bottom surface of the hole portion 6a of the rotating mirror 6, and the screw portion 15 The elastic body 21 is pressed against the bottom surface of the rotating mirror 6 by tightening
This is a method of locking the rotating body of the fluid bearing type optical deflector, in which the rotating body is locked so as not to move during transportation of the optical deflector to prevent impact, and can be screwed into the screw hole 19 of the upper lid 4. An intermediate screw 18 is formed in the middle of the screw shaft 17, and an engaging portion 20 that can be engaged with an engaging hole 22 of an elastic body 21 is provided at the tip of the screw shaft 17, and a screw portion 15 having a U-shaped cross section. A rotary member locking member of a fluid bearing type optical deflector which is mounted on the bottom surface of the mirror 6 and has an elastic body 21 having a detachable engaging hole 22 in the shaft tip engaging portion 20 of the screw portion 15. .. Further, below the screw hole 19 of the upper lid 4 into which the intermediate screw 18 of the screw portion 15 is screwed, the screw portion 1
The tip end engaging portion 20 of No. 5 is pulled out from the engaging hole 22 of the elastic body 21 to provide the concave portion 24 to which the upper end protruding portion 23 of the elastic body 21 can be fitted.

[0005]

The deformed screw is screwed into the hole formed in the upper lid, and the tip end of the screw is engaged with the central hole of the elastic member, which is a cushioning material located on the bottom surface of the rotary mirror hole, and the deformed screw is operated to operate the elastic member. Holds down the rotating body including the rotating mirror by pressing down the rotating mirror. Therefore, it is possible to reduce the impact on the rotating body during transportation of the optical deflector. When the transportation is completed, the deformed screw is unscrewed to pull up the elastic body that is the cushioning member, so that it can be engaged and held in the recess formed on the back surface of the top lid. The troublesome work such as locking between the shaft and the upper lid can be omitted.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An attachment mechanism for a rotary member of a hydrodynamic bearing type optical deflector according to the present invention by a buffer member will be described below with reference to the accompanying drawings. The same reference numerals as those used in the conventional example indicate the same members, and thus detailed description thereof will be omitted. First, the head screw 16 of the odd-shaped screw 15
An engaging portion 20 is provided at the tip of the shaft 17 to which is attached.
An intermediate screw 18 having a diameter smaller than that of the head screw 16 and larger than that of the tip locking portion 20 is provided on the outer periphery of the shaft 17 of the head screw 16 and the tip locking portion 20 which is close to the head screw 16.
To form. On the bottom surface of the upper opening hole portion 6b of the rotating mirror 6 having a U-shaped cross section, an elastic body 21 having a locking hole 22 opened in one direction at substantially the center is placed. Deformed screw 1 on top cover 4
Screw hole 1 into which the intermediate screw 18 formed on the shaft 17 of 5 is screwed
9 is formed.

Next, the rotary body is fixed to the upper lid 4 by using the irregular shaped screws 15.
A method for fixing the above will be described. First, before attaching the upper lid 4, the odd-shaped screw 15 is inserted into the screw hole 19 of the upper lid 4, and the tip engaging portion 20 is inserted into the engaging portion 22 of the elastic body 21. Next, the upper lid 4 to which the deformed screws 15 are assembled as described above
Is fixed to the case 3, and the head screw 16 is operated to screw the intermediate screw 18 provided on the shaft 17 into the screw hole 19 of the upper lid 4, while rotating the tip engaging portion 20 at the end of the shaft 17. Engagement hole 22 of elastic body 21 placed on the bottom surface of upper opening 6b of mirror 6
The head screw 16 is continuously operated while it is inserted into
By screwing the intermediate screw 18 provided on the shaft 17 deeply into the screw hole 19, the tip engaging portion 20 presses the elastic body 21 against the bottom surface of the rotating mirror 6, so that the rotating body including the rotating mirror 6 moves. Held to not. Therefore, when the optical deflector is moved by transportation or the like, the rotating body including the rotating mirror 6 vibrates or vibrates while the tip engaging portion 20 of the deformed screw 15 is engaged and held in the engaging hole 22 of the elastic body 21. Easy to move without impact. Next, in the direction opposite to the above-mentioned operation, the head screw 16
When the elastic body 21 is lifted from the bottom surface of the hole 6a of the rotating mirror 6 by rotating, the upper end protrusion 23 of the elastic body 21 is engaged with the recess 24 formed in the lower surface of the screw hole 19 of the upper lid 4 (Fig. Since it is held in 2), if the distal end engaging portion 20 of the odd-shaped screw 15 is pulled out from the engaging hole 22 of the elastic body, the odd-shaped screw 15 can be easily removed from the upper lid 4. Therefore, when the upper end projection 23 of the elastic body 21 is engaged with the concave portion 24 of the upper lid 4, the rotating body is rotatable, so that it is not necessary to move the optical deflector by transportation or the like. It can respond when it is activated. Further, at the time of the next transportation, the distal end engaging portion 20 of the deformed screw 15 is engaged with the engaging hole 22 of the elastic body 21 to lower the elastic body 21, and at the same time, the intermediate screw 18 of the deformed screw 15 is screwed on the upper lid 4. By screwing into the hole 19, the elastic body 21 is pressed against the bottom of the hole 6a of the rotary mirror 6 as described above, and the rotary body including the rotary mirror 6 is locked by the deformed screw 15 and the elastic body 21.

[0008]

[Effect] Since the rotating body equipped with the rotating mirror having a large inertia is held in the optical deflector by using the deformed screw and the elastic body, the rotating portion is not affected by the impact during transportation of the optical deflector. Since there is no problem in the shrink fitting part and it is easy to remove the odd-shaped screw, the work of removing the upper lid each time to attach and detach the impact material to the hollow rotary shaft as in the conventional example is eliminated, and rotation is eliminated. There is an effect that the body can be easily fixed in the optical deflector.

[Brief description of drawings]

FIG. 1 is a cross-sectional view in which a locking member according to the present invention is provided in a fluid dynamic bearing type optical deflector.

FIG. 2 is a sectional view showing engagement / disengagement of the deformed screw of FIG. 1 and an elastic body.

FIG. 3 is a cross-sectional view of a fluid dynamic bearing type optical deflector including a conventional locking member.

[Explanation of symbols]

 1 Fixed Shaft 2 Hollow Rotating Shaft 3 Case 4 Upper Lid 4a Hole 5 Hub 6 Rotating Mirror 6a Hole 11 Shrink Fit 15 Deformed Screw 16 Head Screw 17 Shaft 18 Intermediate Screw 19 Screw Hole 20 Tip Engagement 21 Elastic 22 Engagement hole 23 Upper end projection 24 Recess

Claims (3)

[Claims] 1. A fluid bearing type housed in a cavity, wherein a rotor mounted on a hollow rotary shaft rotatably provided on the outer periphery of a fixed shaft and having a rotary mirror with a U-shaped cross section is formed by a top lid and a case. In the optical deflector, before assembling the upper lid into the case, an intermediate screw formed in the intermediate portion of the screw shaft is screwed into the screw hole of the upper lid, and the tip engaging portion of the screw shaft is engaged with the engaging hole of the elastic body. A step of assembling the upper lid into a case, and a step of pressing the elastic body against the bottom surface of the rotating mirror by tightening the screw portion after the assembly is completed, and locking the rotating body so as not to move. A method of locking a rotating body of a fluid bearing type optical deflector, characterized in that an impact on the rotating body is prevented during transportation of the optical deflector. 2. A screw part, wherein an intermediate screw that can be screwed into the screw hole of the upper lid is formed in the middle of the screw shaft, and an engaging part that can be engaged with the engaging hole of the elastic body is provided at the tip of the screw shaft. , A rotary member locking member of a hydrodynamic bearing type optical deflector having an elastic body mounted on the bottom surface of a rotary mirror having a U-shaped cross section and having a detachable engaging hole at a shaft tip engaging portion of a screw portion. .. 3. The upper end protrusion of the elastic body is formed by pulling out the tip engaging portion of the screw portion from the engaging hole of the elastic body under the screw hole of the upper lid into which the intermediate screw of the screw portion is screwed. The rotary member locking member of the fluid-bearing type optical deflector according to claim 2, further comprising a concave portion that can be engaged.