JPH03242634A - Optical system driving device - Google Patents

Abstract

PURPOSE:To decrease the number of components, facilitate the assembly, and to reduce the cost as compared with a conventional example which uses a wire by driving a lamp unit and a mirror base unit at a specific speed ratio by the combination of rack gears and planetary gears. CONSTITUTION:When a copy is taken, a document on an original platen 1 is scanned by the light source lamp unit 7. At this time, a driving gear 22 rotates in a direction C and a movable rack gear 18 moves in a direction A together with the mirror base unit 10. When the gear 18 moves, the planetary gear 19 and 20 which are united together through an idle gear 21 rotate, but they are equal in the number of teeth and the module ratio is 2:1, so that sup port member of the gear 19 which engages a fixed rack gear 17, i.e. the unit 7 moves in the same direction with the unit 10 twice as fast as the unit 10. The number of components is small and adjustments are facilitated as compared with the conventional example which require plural pulleys.

Description

Detailed Description of the Invention <Industrial Application Field> The present invention is 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. It relates to a system drive device.

<Prior Art> For example, as shown in FIGS. 6 and 7, a copying machine with a fixed document table irradiates light onto a document placed on a document table 40 and uses the reflected light to expose the document. An optical system 42 for guiding the light to the body drum 41 is provided.

This optical system 42 includes a light source lamp 43 and a first mirror 4.
4, this lamp unit 45 scans the document, and the reflected light is transmitted to the second . A mirror base unit 48 having a third mirror 46, 47, a lens 49, a fourth . The light is guided to the photosensitive drum 41 via a mirror holder 52 having a fifth mirror 50, 51 and a sixth mirror 53.

The mirror base unit 48 is configured to move at 1/2 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 as the lamp unit 45 moves. The mirror base unit 48 and the lamp unit 45 are fixed to a wire 54, and move at a predetermined speed ratio as the wire 54 moves.

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

<Problems to be Solved by the Invention> However, in such a conventional optical system drive device, since the wire 54 is used, a large number of pulleys are required, making the configuration complicated, and the winding of the wire 54 becomes difficult. It takes time to attach, is expensive, and the wire 54
The problem is that it is necessary to take into account factors such as the growth of

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

<Means for Solving the Problems> In the present invention, in order to achieve the above-mentioned object, the light source lamp unit and the mirror base unit provided in the optical path between the light source lamp unit and the photoreceptor are An optical system drive device that drives at a predetermined speed ratio when the system is operated, a fixed rack gear attached to the device body, a movable rack gear attached to the mirror base unit, and a first planetary gear meshed with the fixed rank gear. , a second J planetary gear whose pitch circle diameter ratio with the first planetary gear corresponds to the predetermined speed ratio, and which rotates coaxially and integrally with the first planetary gear; and this second planetary gear. a gear and an idle gear meshing with the movable rack gear,
A shaft that supports both of the planetary gears and a shaft that supports the idle gear are integrally provided in 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 wires.

<Examples> Examples of the present invention will be described in detail below with reference to the drawings.

FIG. 0 is a schematic configuration diagram of one embodiment of the present invention, and FIG.
The figure is an exploded perspective view of the main parts.

As shown in FIG. 1, the copying machine of this embodiment is equipped with an optical system 3 below the document table l that scans the original on the document table l and guides the reflected light to the photosensitive drum 2. There is. This optical system 3 includes 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; a mirror holder 14 having a fixed focus lens 11; a fourth mirror 12 and a fifth mirror 13; 6 mirror 15
It is equipped with

Furthermore, the optical system 3 includes an optical system drive device 16 that drives the light source lamp unit 7 and the mirror base unit 10 when scanning the original on the original table l. The mirror base unit 10 includes a light source lamp unit 7 as described below.
It is designed to be driven in the same direction at 1/2 the speed.

As shown in FIG. 2, the optical system drive device 16 of this embodiment includes a fixed rack gear 17, a movable rack gear 18,
It includes a large-diameter planetary gear 19 that is a first planetary gear, a small-diameter planetary gear 20 that is a second planetary gear, an idle gear 21, and a drive gear 22.

The fixed rack gear 17 is attached to a frame 23 on the main body side shown in FIG. It is provided. As shown in FIG. 2, the fixed rack gear 17 has tapped holes 17a, 17a formed at both ends, while the frame 23 has elongated holes 23a, 23a formed therein. 17a, I 7a
2 through the elongated hole 23a of the frame 23 through the washer 24.
By screwing the screw 2525 through 3a,
The fixed rack gear 17 is attached to the frame 23. Therefore, the fixed rack gear 17
The mounting position in the longitudinal direction can be adjusted by the long holes 23a, 23a.

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 its tooth surface facing upward. The movable rack gear 18 is connected to the mirror base unit IO by screws (not shown) through tapped holes 18a formed at the end of the mirror base unit IO.

The planetary gears 19.20 and the idle gears 2I are provided between the fixed rack gear 17 and the movable rack gear 18,
The planetary gears 19 and 20 are integrally formed, the planetary gear 9 meshing with the fixed rack gear 17, and the idle gear 21 meshing with the planetary gear 2o and the movable rack gear 18. Also,
The planetary gear 1920 is attached to the rotating shaft 26 and the idle gear 21 is attached to the 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 ratio of the diameters of the pinch circles of the planetary gear I9 and the planetary gear 20 is a ratio corresponding to the speed ratio of the light source lamp unit 7 and the mirror base unit 10, that is, 2.
In this embodiment, both gears 19.2
The number of 0 teeth is the same, and the module ratio is 2:1.

The drive gear 22 meshes with the movable rack gear 18 and is connected to a drive motor (not shown) to drive the movable rack gear 8.

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

The planetary gear 19 meshes with the fixed rack gear 17 and the fixed rack gear 17 is stopped, so when the planetary gear 19 rotates once in the C direction, the rotating shaft 26 of the planetary gear 19 moves in six directions by the pitch circumference. do. Even if it's a planetary gear! If 9 is a module l and the number of teeth is 18, then when the planet gear 19 rotates once, the rotating shaft 26 will move by I8π in six directions.

Next, the planetary gear 20 that meshes with the idle gear 2 makes one rotation in the same way as the planetary gear 19 makes one rotation, 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 movement distance is 9
It becomes π. Therefore, the idle gear 21 rotates in the D direction by this pitch circle movement distance of 9π, and transmits this to the movable rack gear 18. As a result, movable rack gear 1
8 is the rotation of the planetary gears I 9, 20 and the idle gear 21 @ 26, 27, that is, the movement distance of the light source lamp unit 7 in the direction A of 18π, and the movement of the idle gear 21 in the direction B, which is returned in the opposite direction. 9 which is the difference from the distance 9π
It will move by π in six directions.

Therefore, with respect to the moving speed V of the light source lamp unit 7, the movable rack gear 18 moves in the same direction as the light source lamp unit 7 at a speed of vX9π/18π, that is, v/2.

Next, the exposure operation in the optical system will be explained.

When copying is performed, the light source lamp unit 7 scans the original placed on the original table l. At this time, the drive gear 22 rotates in the C direction, which causes the movable rack gear 18
moves in six directions together with the mirror base unit IO.

The movement of the movable rack gear 18 is transmitted to the light source lamp unit 7 connected to the rotating shaft 26, 27 via the idle gear 21 and the planetary gears 19, 20 according to the above-mentioned movement principle. It will move at twice the speed of lO.

In this way, the light source lamp unit 7 and the mirror base unit IO can be driven at a predetermined speed ratio without using wires, so compared to the conventional example that requires wires and a large number of pulleys. Fewer parts,
It also becomes easier to assemble, making it possible to reduce costs.

Note that the light emitted from the light source lamp 4 of the light source lamp unit 7 is reflected by the original, and is reflected by the first mirror 6 and the second mirror 8.
, the third mirror 9, the lens II, the fourth mirror 12, the fifth mirror 13, and the sixth mirror 15.
An electrostatic latent image corresponding to the original image is formed on the surface of the photoreceptor tram 2. Copying is then performed through normal processes.

Further, in this embodiment, from the document table 1 to the lens 11,
Fine adjustment of the optical path length, that is, focus adjustment, can be easily performed by adjusting the position of the fixed rack gear 17 on the frame 23.

FIG. 3 is an exploded perspective view corresponding to FIG. 2 of another embodiment of the present invention, and parts corresponding to the above-described embodiment are given the same reference numerals.

In this embodiment, fixed rack gear +7. The movable rack gear 18o has guide grooves 17ob and 18°b extending along the longitudinal direction formed on its side edges, respectively, and further includes a planetary gear 19° and an idle gear 21.
, each of the guide grooves 17, b, I8. Guide plates 28 and 29 that fit into the gears b and rotate integrally with each gear 19o21o are attached.

By providing such a guide mechanism, it is possible to effectively prevent lateral displacement of the light source lamp unit 7 and the mirror base unit 10 during movement.

In this embodiment, unlike the above-mentioned embodiment, the planetary gear 19
．． and planetary gear 20. By using the same modules and setting the ratio of the number of teeth to 2.1, the ratio of the pitch circle diameter is made to correspond to the speed ratio of the light source lamp unit 7 and the mirror base unit IO.

The other configurations are similar to those of the above embodiment.

Note that in this embodiment, the rack gear 17. ．． Guide groove 17. on the 18° side. Although guide plates 28 and 29 are provided for the planetary gear I90 and the idle gear 21o, respectively, it is of course possible to use the opposite configuration.

FIG. 4 is a block diagram corresponding to FIG. 1 of still another embodiment of the present invention, and FIG. 3 is a perspective view of a light source lamp unit.

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

The rest of the structure is the same as the embodiment shown in FIG.

<Effects of the Invention> As described above, according to the present invention, a fixed rack gear attached to an apparatus main body, a movable rack gear attached to the mirror base unit, a first planetary gear meshing with the fixed rack gear, a second planetary gear whose pitch circle diameter ratio with the first planetary gear corresponds to the predetermined speed ratio, and which rotates coaxially and integrally with the first planetary gear; and an idle gear that meshes with the movable rack gear, and a shaft that supports both the planetary gears and a shaft that supports the idle gear are integrally provided in the light source lamp unit, so that wires are not required. It is now possible to drive the light source lamp unit and mirror base unit at a predetermined speed ratio, and compared to conventional models that require wires and multiple pulleys, there are fewer parts and assembly is easier, reducing costs. It becomes possible to aim for.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram of an embodiment of the present invention, and FIG.
FIG. 3 is an exploded perspective view of another embodiment of the present invention corresponding to FIG. 2, FIG. 4 is a schematic configuration diagram of still another embodiment of the present invention, and FIG. The drawings are a perspective view of the light source lamp unit of the embodiment shown in FIG. 4, FIG. 6 is a schematic configuration diagram of the optical system, FIG. 7 is a plan view, and FIG. 8 is a perspective view showing the drive mechanism. l...Original table, 3...Optical system, 4...Light source lamp, 7...Light source lamp unit, 10...Mirror base unit, 11 Lens, 16 Optical system drive device, 17° 17o Fixed rack gear, 18.188...Movable rack gear, 19 Planetary gear (first planetary gear), 20 Planetary gear (secondary planetary gear), 21 - Idle gear, 26.
27 Rotation axis.

Claims (1)

[Claims] (1) In an optical system drive device that drives a light source lamp unit and a mirror base unit provided in an optical path between the light source lamp unit and the photoreceptor at a predetermined speed ratio when the optical system is operated, the device main body a fixed rack gear attached to the mirror base unit, a movable rack gear attached to the mirror base unit, a first planetary gear that meshes with the fixed rack gear, and a ratio of pitch circle diameters of the first planetary gear to the predetermined speed. a second planetary gear that rotates coaxially and integrally with the first planetary gear at a ratio corresponding to the second planetary gear; and an idle gear that meshes with the second planetary gear and the movable rack gear; An optical system driving device characterized in that a supporting shaft and a shaft supporting the idle gear are integrally provided with the light source lamp unit.