JP2611023B2 - Optical system drive - Google Patents

Description

The present invention relates to an optical system suitable for an optical system in which a light source lamp unit and a mirror base unit are driven at a predetermined speed ratio, such as a copying machine. The present invention relates to a system driving device.

<Prior Art> For example, a copy machine of a fixed platen type is shown in FIGS.
As shown in the figure, an optical system 42 is provided for irradiating a document placed on a document table 40 with light and guiding the reflected light to a photosensitive drum 41. The optical system 42 includes a lamp unit 45 having a light source lamp 43 and a first mirror 44. The lamp unit 45 scans an original, and the reflected light is transmitted to the second unit.
2, a mirror base unit 48 having third mirrors 46 and 47,
Mirror holder 5 having lens 49, fourth and fifth mirrors 50 and 51
The light is guided to the photosensitive drum 41 via the second and sixth mirrors 53.

The mirror base unit 48 moves at half the speed of the lamp unit 45 in order to keep the optical path length from the document table 40 to the lens 49 constant with the movement of the lamp unit 45. The mirror base unit 48 and the lamp unit 45 are fixed to a wire 54,
As the wire 54 moves, the wire 54 moves at a predetermined speed ratio.

That is, as shown in FIG. 8, a wire 54 having one end attached to the frame 55 is fixed to the lamp unit 45 via one pulley 56 of the mirror base unit 48. After being wound around the drive pulley 58 via the 57 and further around the other pulley 60 of the mirror base unit via the idle pulley 59 at the end of the frame, it is attached to the frame 55 by the spring 61.

<Problems to be Solved by the Invention> However, in such a conventional optical system driving device, since the wire 54 is used, a large number of pulleys are required, the configuration becomes complicated, and the winding of the wire 54 is performed. It takes a long time to attach the wire, the cost is high, and there is a drawback that the elongation of the wire 54 must be taken into consideration.

The present invention has been made in view of the above points,
It is an object of the present invention to be able to drive a light source lamp unit and a mirror base unit at a predetermined speed ratio without using wires.

<Means for Solving the Problems> According to the present invention, in order to achieve the above-described object, an optical source lamp unit and a mirror base unit provided in an optical path between the optical source lamp unit and the photosensitive member are optically connected. An optical system driving device that drives at a predetermined speed ratio when the system operates, a fixed rack gear attached to the device main body, a movable rack gear attached to the mirror base unit, and a first planetary gear meshing with the fixed rack gear. The first planetary gear has the same number of teeth as the first planetary gear, and has a module ratio with the first planetary gear at a ratio corresponding to the predetermined speed ratio, and coaxially rotates with the first planetary gear. A second planetary gear; and an idle gear that meshes with the second planetary gear and the movable rack gear, and supports a shaft that supports the planetary gears and the idle gear. A holding shaft is provided integrally with the light source lamp unit.

<Operation> According to the above configuration, it is possible to drive the light source lamp unit and the mirror base unit at a predetermined speed ratio without using a wire.

<Example> Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a schematic structural view of one embodiment of the present invention, FIG. 2 is an exploded perspective view of a main part, and FIG. 3 is a diagram showing the gears 19 to 21 of FIGS. FIG. 3 is a view as viewed from a (gear 19) side.

As shown in FIG. 1, the copying machine of this embodiment includes an optical system 3 that scans an original on the original table 1 and guides the reflected light to a photosensitive drum 2 below the original table 1. I have. The optical system 3 includes a light source lamp unit 7 having a light source lamp 4, a reflector 5 and a first mirror 6, a mirror base unit 10 having a second mirror 8 and a third mirror 9, and a fixed focus lens 11. , Fourth mirror 12 and fifth mirror
A mirror holder 14 having 13 and a sixth mirror 15 are provided.

Further, the optical system 3 scans a document on the platen 1
An optical system driving device 16 for driving the light source lamp unit 7 and the mirror base unit 10 is provided. The mirror base unit 10 is driven in the same direction at half the speed with respect to the light source lamp unit 7, as in the later operation.

As shown in FIG. 2, the optical system driving device 16 of this embodiment includes a fixed rack gear 17, a movable rack gear 18,
A large-diameter planet gear 19 as a planet gear, a small-diameter planet gear 20 as a second planet gear, an idle gear 21 and a drive gear 22 are provided.

The fixed rack gear 17 is provided on a frame 23 on the main body side shown in FIG. 2 provided below the document table 1 with the tooth surface facing downward over the length of the document table 1 in the longitudinal direction of the document table 1. Is provided. As shown in FIG. 2, the fixed rack gear 17 has screw holes 17a, 17a at both ends, while the frame 23 has long holes 23a, 23a.
The fixed rack gear 17 is attached to the frame 23 by screwing the screws 25, 25 through the long holes 23a, 23a of the frame 23 through the washers 24 into the 7 screw holes 17a, 17a. Therefore, the fixed rack gear 17 can adjust the mounting position in the longitudinal direction by the long holes 23a, 23a of the frame 23.

The movable rack gear 18 is shorter in length than the fixed rack gear 17, is provided so as to be movable in the longitudinal direction, and is arranged parallel to the fixed rack gear 17 with the tooth surface facing upward. The movable rack gear 18 is connected to the mirror base unit 10 by screws (not shown) through screw holes 18a, 18a formed in the mounting end on the mirror base unit 10 side.

The planetary gears 19, 20 and the idle gear 21 are provided between the fixed rack gear 17 and the movable rack gear 18, and
The planet gears 19 mesh with the fixed rack gear 17, and the idle gear 21 meshes with the planet gear 20 and the movable rack gear 18. The planet gears 19 and 20 are attached to a rotating shaft 26, and the idle gear 21 is attached to a rotating shaft 27. These rotating shafts 26 and 27 are attached to a support member (not shown) connected to the light source lamp unit 7.

In the present invention, the number of teeth of the planetary gear 19 and the planetary gear 20 are made equal, and the ratio of the modules is set to a ratio corresponding to the speed ratio between the light source lamp unit 7 and the mirror base unit 10, that is, 2: 1. And

The drive gear 22 meshes with the movable rack gear 18 and is connected to a drive motor (not shown) so as to drive the movable rack gear 18.

In the above configuration, first, the principle of movement between the light source lamp unit 7 and the mirror base unit 10 in the optical system driving device 16 will be described.

Since the planetary gear 19 meshes with the fixed rack gear 17 and the fixed rack gear 17 is stopped, when the planetary gear 19 makes one rotation in the direction C, the rotating shaft 26 of the planetary gear 19 moves in the direction A by the pitch circumference. I do. If the planetary gear 19 has 18 teeth in the module 1 and the planetary gear 19 makes one rotation, the rotation shaft
26 will move in the A direction by 18π. Next, the planetary gear 20 meshing with the idle gear 21 makes one rotation in the same manner by one rotation of the planetary gear 19, but the planetary gear 19 and the planetary gear 20 have the same number of teeth and a module ratio of 2: 1. Therefore, the pitch circle moving distance is 9π. Therefore, the idle gear 21 rotates in the D direction by the pitch circle moving distance 9π, and transmits this to the movable rack gear 18. As a result, the movable rack gear 18 moves the planetary gears 19 and 20 and the rotating shafts 26 and 27 of the idle gear 21, that is, the moving distance 18π in the direction A of the light source lamp unit 7 and the B of the idle gear 21 returned in the opposite direction. It moves in the A direction by 9π, which is the difference from the moving distance 9π in the direction.

Accordingly, the movable rack gear 18 moves in the same direction as the light source lamp unit 7 at a speed of v × 9π / 18π, that is, v / 2 with respect to the moving speed v of the light source lamp unit 7.

 Next, the exposure operation in the optical system is described.

When copying is performed, the light source lamp unit 7 scans the original placed on the original table 1. At this time, the drive gear 22 rotates in the C direction, whereby the movable rack gear 18 moves in the A direction together with the mirror base unit 10. The movement of the movable rack gear 18 is transmitted to the light source lamp unit 7 connected to the rotating shafts 26 and 27 via the idle gear 21 and the planetary gears 19 and 20 according to the above-described movement principle. It will move at twice the speed of 10.

As described above, the light source lamp unit 7 and the mirror base unit 10 can be driven at a predetermined speed ratio without using wires, so that the light source lamp unit 7 and the mirror base unit 10 can be driven in comparison with a conventional example requiring wires and a large number of pulleys. The number of parts is small,
Assembly is also facilitated, and cost can be reduced.

The light emitted from the light source lamp 4 of the light source lamp unit 7 is reflected by the original, and the first mirror 6, the second mirror 8, the third mirror 9, the lens 11, the fourth mirror 12, the fifth mirror 13 and The photosensitive drum 2 reaches the photosensitive drum 2 via the sixth mirror 15, and an electrostatic latent image corresponding to the document image is formed on the surface of the photosensitive drum 2. Hereinafter, copying is performed through a normal process.

In this embodiment, the platen 1 and the lens 11
Fine adjustment of the optical path length up to, that is, focus adjustment, can be easily performed by adjusting the mounting position of the fixed rack gear 17 to the frame 23.

FIG. 4 is a block diagram corresponding to FIG. 1 of still another embodiment of the present invention, and FIG. 5 is a perspective view of a light source lamp unit.

In this embodiment, the drive gear 22 is eliminated and the drive motor 30 is mounted on the light source lamp unit 7, and the drive motor 30 directly drives the planetary gears 19 and 20.

 Other configurations are the same as those of the embodiment of FIG.

<Effect of the Invention> As described above, according to the present invention, a fixed rack gear attached to the apparatus main body, a movable rack gear attached to the mirror base unit, a first planetary gear meshing with the fixed rack gear, and A second planetary gear having the same number of teeth as the first planetary gear and having a module ratio with the first planetary gear at a ratio corresponding to the predetermined speed ratio and coaxially rotating integrally with the first planetary gear; Planetary gear and this second
A planetary gear and an idle gear that meshes with the movable rack gear, and a shaft that supports the planetary gears and a shaft that supports the idle gear are provided integrally with the light source lamp unit. Without driving, the light source lamp unit and the mirror base unit can be driven at a predetermined speed ratio, the number of parts is smaller than in the conventional example requiring wires and a large number of pulleys, and assembly is easy, Costs can be reduced.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of an embodiment of the present invention, and FIG.
FIG. 3 is an exploded perspective view of a main part of the drawing, FIG. 3 is a view showing gears 19 to 21,
FIG. 4 is a schematic configuration diagram of another embodiment of the present invention, FIG. 5 is a perspective view of a light source lamp unit of the embodiment of FIG. 4, FIG. 6 is a schematic configuration diagram of an optical system, and FIG. FIG. 8 is a perspective view showing a drive system. 1 ... platen, 3 ... optical system, 4 ... light source lamp, 7 ...
... Light source lamp unit, 10 ... Mirror base unit,
11: Lens, 16: Optical system driving device, 17: Fixed rack gear, 18: Movable rack gear, 19: Planetary gear (first
Planetary gear), 20 ... planetary gear (second planetary gear), 21 ...
Idle gear, 26, 27 ... Rotary shaft.

Claims (1)

(57) [Claims] An optical system driving device for driving a light source lamp unit and a mirror base unit provided in an optical path between the light source lamp unit and a photoconductor at a predetermined speed ratio when the optical system is operated. A fixed rack gear attached to the apparatus main body, a movable rack gear attached to the mirror base unit, a first planetary gear meshing with the fixed rack gear, and a first planetary gear having the same number of teeth as the first planetary gear. A second planetary gear having a ratio of the module to the planetary gear corresponding to the predetermined speed ratio and rotating integrally and coaxially with the first planetary gear; meshing with the second planetary gear and the movable rack gear; And a shaft that supports the two planetary gears and a shaft that supports the idle gear are provided integrally with the light source lamp unit. Optical system driving apparatus characterized by there.