JPH04276734A - Image forming device - Google Patents

Abstract

PURPOSE:To eliminate the need of the complex stretching of a belt with an end and to improve assembling workabilities by individually moving first and second mobile bodies by means of first and second driving belts endlessly travelled. CONSTITUTION:First and second carriages 15 and 16 are driven by a driving device 17, and the driving device 17 has the first and second driving belts 18 and 19 endlessly travelled. The first and second driving belts 18 and 19 serve as timing belts, and stretched between a first driving pulley 32 and an idle roller 33, and between a second driving pulley 34 and an idle roller 35, respectively. When a pulse motor 39 is operated, the driving pulleys 32 and 34 are rotated, the first driving belt 18 is travelled, and simultaneously, the second driving belt 19 is travelled at the half speed of the first driving belt 18. Therefore, the first and second carriages 15 and 16 are moved and an original is exposed.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus having an improved carriage drive device that constitutes an optical system of, for example, an electronic copying machine.

0002

2. Description of the Related Art An electronic copying machine includes, for example, first and second carriages 101 and 102, as shown in FIG. A mirror is provided to reflect light reflected from the original. Further, a mirror is provided on the second carriage 102 to guide the light reflected from the mirror to the photosensitive drum. Incidentally, the first and second carriages 101 and 102 are configured to move along the surface of the document by the running of a drive belt 103.

One end of the drive belt 103 is fixed to a fixture 105 provided at one end inside the copying machine main body 114, and the middle part is connected to the pulley 106 of the second carriage 102 and the inside of the main body 114. After being stretched over a fixed pulley 107, it is stretched over a drive pulley 108 provided at the other end of the copying machine main body 114, and further fixed to the first carriage 101 by a fixture 109. Thereafter, it is stretched around a pulley 110 of the second carriage 102, and the other end is fixed to the middle part of the drive belt 103 by a fixture 111.

[0004] When the drive motor 104 is driven in the direction of the arrow, the drive pulley 108 is
is rotated, thereby causing the drive belt 103 to run in the direction of the arrow and the first carriage 101 to move along the guide rail (
(not shown), and the second carriage 101 is moved at 1/2 the speed of the first carriage 101.
02 is moved along the guide rail to maintain a constant optical path length, thereby exposing the surface of the document to form an image of the document on the photosensitive drum.

[0005]

[Problems to be Solved by the Invention] However, in the past, an end belt was used as the drive belt 103 and the belt was stretched within a narrow space within the main body 114, resulting in poor assembly workability. was.

[0006] Furthermore, the first and second carriages 101
, 102 guide rails were individually provided, which resulted in a large number of parts and poor assembly workability.

[0007] Accordingly, the present invention makes it possible to move the first and second moving bodies at a predetermined speed without having to route the drive belt in a complicated manner. An object of the present invention is to provide an image forming apparatus in which a guide member for guiding the image can be shared.

[0008]

[Means for Solving the Problems] In order to solve the above problems, the present invention provides a first movable body equipped with a light source that irradiates light onto a document, and an optical system that guides light reflected from the document to an imaging section. a second moving body including a second moving body; a first drive belt connected to the first moving body and moving the first moving body by running endlessly; and a first drive belt coupled to the second moving body. A second drive belt that moves the second movable body and the first drive belt run by running endlessly, and the second drive belt is moved to 1/1/2 of the first drive belt. and a belt driving means for maintaining a constant optical path length from the original to the imaging unit by running at a speed of 2, the first and second driving belts being toothed belts, and the first and second driving belts being toothed belts. The drive belt is stretched between the first drive gear and the driven gear, the second drive belt is stretched between the second drive gear and the driven gear, and the second drive belt is stretched between the first drive gear and the driven gear.
and a second drive gear are mounted on the same shaft to have a gear ratio of 2:1;
The movable body is provided with a guide means for guiding the movement of the movable body by the same guide member.

[0009]

[Operation] By connecting the first drive belt that runs endlessly to the first moving body and the second drive belt that runs endlessly to the second moving body, there is no need to connect the drive belts in a complicated manner. , the first and second movable bodies can be moved at a predetermined speed, and the structure can be simplified by guiding the movement of the first and second movable bodies by the same guide member.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained below with reference to an embodiment shown in FIGS. 1 to 5.

FIG. 2 shows an electronic copying machine, and numeral 1 in the figure is the main body of the copying machine. The photocopy main body 1 is placed on an L-shaped mounting table 21. A photosensitive drum 2 is provided in the copying machine main body 1 so as to be rotatable in the direction of the arrow, and around the photosensitive drum 2 there are sequentially arranged along the rotational direction.
A charging charger 3, an exposure section 4, a developing device 5, transfer and peeling chargers 6 and 7, a cleaning device 8, and a static eliminator 9 are provided.

A transport path 1 is provided approximately at the center of the copying machine main body 1.
0 is provided, and in this conveyance path 10, registration rollers 12, the above-mentioned transfer and peeling charms are sequentially provided along the conveyance direction of the paper.
Jars 6 and 7, a conveyor belt 11, a fixing device 13, and a discharge roller 14 are provided. Upper, middle, and lower paper feed cassettes 22a, 22b, 2 are provided on one side of the copying machine main body 1.
2c, and a paper discharge tray 23 is provided on the other side.

[0013] The paper feed cassettes 22a, 22b, 22c
The paper inside is taken out by the take-out roller 24, and the paper taken out by this take-out roller 24 is transferred to the paper feed roller 2.
5a and separation roller 25b, the sheets are separated one by one and fed. Further, an exposure system 41 is provided on the upper side of the copying machine main body 1.

This exposure system 41 includes an exposure lamp 42 and a first reflection mirror 43 provided on a first carriage 15 as a first moving body, and a second carriage 16 as a second moving body. It is composed of second and third reflective mirrors 44, 45 provided, a lens 46, and fourth to sixth reflective mirrors 47, 48, 49. The first and second carriages 15 and 16 are configured to reciprocate along a document glass 50 provided on the upper surface of the copying machine main body 1. Reference numeral 51 denotes a line flow fan, and the line flow fan 51 exhausts hot air inside the copying machine main body 1 to the outside through an exhaust port 61.

A transport path 31 for double-sided and overlapping copies is provided inside the mounting table 21. A pair of feed rollers 26 .

Further, an automatic document conveying device 55 is provided on the upper surface of the document table 50, and this automatic document conveying device 55
The original is automatically set on the original table 50.

During image formation, the exposure system 41 scans the original on the original platen 50 with light from the exposure lamp 42 . This light is reflected from the original, passes through the first to third mirrors 43 to 45, and further passes through the lens 46, and then forms an image on the photosensitive drum 2 via the fourth to sixth mirrors 47 to 49. Ru. The surface of the photoreceptor drum 2 is charged with a charger 3
The image formation forms an electrostatic latent image of the document. This electrostatic latent image is sent to a developing device 5 by the rotation of the photosensitive drum 2, and toner as a developer is supplied from the developing device 5.

On the other hand, at this time, the paper feed cassette 22a
.about.22c, sheets are taken out one by one and sent to the pair of registration rollers 12. The paper is this registration roller pair 1
After being aligned in step 2, it is sent to an image transfer section 6a between the photosensitive drum 2 and the transfer charger 6, where the image is transferred. The paper to which this image has been transferred is peeled off from the photosensitive drum 2 by the action of the peeling charger 7. Then, this peeled paper is sent to the fixing device 13, and this fixing device 1
After the image is fixed in step 3, the paper is discharged onto a paper discharge tray 23 via a discharge roller 14.

In the case of double-sided copying or overlapping copying, the gate 71 is rotated in the direction shown by the broken line, and the paper is fed into the conveying path 31 side and sent again to the image transfer section 6a. The image is transferred. Incidentally, the first and second carriages 15 and 16 are driven by a drive device 17 as shown in FIGS. 1 and 3. The above drive device 1
Reference numeral 7 denotes first and second drive belts 18, 1 that run endlessly.
It is equipped with 8, 19, 19.

The first drive belt 18 is a timing belt, and is stretched between the first drive pulley 32 and the idle roller 33, and the second drive belt 19 is a timing belt, which is stretched between the first drive pulley 32 and the idle roller 33. It is stretched between the second drive pulley 34 and the idle roller 35.

The first and second drive pulleys 32, 3
2, 34, and 34 have a gear ratio of 2:1 and are attached to the shaft 36. One end of the shaft 36 is connected to a pulse motor 39 via a gear 37 and a belt 38. Both ends of the first carriage 15 are fixed to the first drive belts 18, 18 via clamps 52.

By setting the gear ratio of the first drive pulley 32 and the second drive pulley 34 to 2:1, the first drive belt 18 has twice the power of the second drive belt 19. It travels at a speed that maintains a constant optical path length.

On the other hand, the first and second drive belts 1
As shown in FIG. 4, the idler pulleys 33 and 35 that span the idler pulleys 5 and 16 are movably provided and are biased by coil springs 62 and 63 as biasing members. One end of the coil springs 62 and 63 is attached to the main body frame 6.
0, and the other end is connected to the idle pulleys 33, 35 via fixtures 64, 65. 1st above
As shown in FIG. 5, the second carriages 15 and 16 are guided in their travel by the same guide rail 59. The guide rail 59 is the main body frame.
It is formed by bending a part of the frame 60. The first and second carriages 15 and 16 have an arc-shaped constriction portion 57,
58, and these constricted portions 57, 58 are connected to the guide rail.
59 and move it.

The second carriage 16 is positioned by abutting against the main body frame 60, and the first carriage 15 is positioned by abutting its end against the first carriage 16.

When the pulse motor 39 operates, the drive pulleys 32, 32 and 34, 34 are driven to rotate via the belt 38, pulley 37, and shaft 36. As a result, the first drive belt 18 runs, and the second drive belt 19 runs at half the speed of the first drive belt 18. As a result, the first and second carriages 15 and 16 are moved and the original is exposed.

As described above, since the first and second carriages 15 and 16 are individually moved by the endlessly running first and second drive belts 18 and 19, the first and second carriages 15 and 16 are The first and second carriages 15, 16 can be made to run at a predetermined speed without having to complicatedly wrap an end drive belt around the carriages 15, 16.

[0027] Furthermore, the first and second carriages 15,
16 is guided by the same guide rail 59, the guide rail 59 can be shared, and the number of parts can be reduced.

[0028]

[Effects of the Invention] As explained above, according to the present invention,
The first and second moving bodies run endlessly on the first and second moving bodies.
Since the movable parts are moved individually by the drive belts of the movable parts, there is no need to wrap an end belt around the first and second movable bodies in a complicated manner as in the conventional case, and the assembly work efficiency can be improved.

Furthermore, since the first and second movable bodies are guided by the same guide member, the guide member can be shared;
The number of parts can be reduced, reducing costs and improving assembly workability.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a carriage driving device according to an embodiment of the present invention.

FIG. 2 is a configuration diagram showing an electronic copying machine equipped with the drive device of FIG. 1;

FIG. 3 is a side view showing the drive device of FIG. 1;

FIG. 4 is a perspective view showing a coil spring of the drive device in FIG. 1;

FIG. 5 is a configuration diagram showing a guide section of the drive device in FIG. 1;

FIG. 6 is a configuration diagram showing a conventional carriage driving device.

[Explanation of symbols]

2... Photosensitive drum (imaging section), 15... First carriage (
16...Second carriage (second moving body), 18...First drive belt, 19...Second drive belt, 32...First drive pulley (belt drive means) ), 33
... Driven gear, 34 ... Second drive pulley (belt drive means), 35 ... Driven gear, 42 ... Exposure lamp (light source), 43
, 44, 45...mirror (optical element).

Claims (3)

[Claims] 1. A first movable body equipped with a light source that irradiates light onto a document at a predetermined position; a second movable body equipped with an optical element that guides light reflected from the document to an imaging section; Said first
By connecting to the moving body and traveling endlessly, the first
a first drive belt that moves the moving body; a second drive belt that is connected to the second moving body and moves the second moving body by running endlessly; and the first drive belt. and a belt driving means for maintaining a constant optical path length from the document to the imaging unit by causing the second driving belt to travel at 1/2 the speed of the first driving belt. The first and second drive belts are toothed belts, the first drive belt is stretched between the first drive gear and the driven gear, and the second drive belt is stretched between the first drive gear and the driven gear.
The drive belt is stretched between a second drive gear and a driven gear, and the first and second drive gears are attached to the same shaft to have a gear ratio of 2:1. image forming device. 2. A first movable body equipped with a light source that irradiates light onto the document at a predetermined position; and a second movable body equipped with an optical element that guides light reflected from the document to an imaging section. Said first
By connecting to the moving body and traveling endlessly, the first
a first drive belt that moves the moving body; a second drive belt that is connected to the second moving body and moves the second moving body by running endlessly; and the first drive belt. belt driving means for maintaining a constant optical path length from the document to the image forming section by causing the second driving belt to travel at 1/2 the speed of the first driving belt; a guide means for guiding the movement of the first and second movable bodies by the same guide member, the first and second drive belts are toothed belts, and the first drive belt is a first drive belt. The second drive belt is stretched between a driving gear and a driven gear, the second driving belt is stretched between a second driving gear and a driven gear, and the first and second driving gears are connected to the same shaft. An image forming apparatus characterized in that it is attached and has a gear ratio of 2:1. 3. A driven gear that spans the first and second drive belts is provided movably, and by energizing the driven gear, a predetermined tension is applied to the first and second drive belts. 4. The image forming apparatus according to claim 3, further comprising a biasing means for applying a bias.