JPS61138247A - Scanning system driving device of copying machine - Google Patents

Abstract

PURPOSE:To move forth and back and also stop a scanning system only by using one solenoid by providing a cam which moves integrally with the scanning system to the scanning system and also providing an inversible lever on a changeover lever. CONSTITUTION:The cam 50 is fixed on the reverse surface of an original platen 4 over the inversible lever 45 and while the tip 45a of the inversible lever 45 is in slide contact with the slide surface 50a of the cam 50, claws 41 and 42 of the changeover lever 40 do not engage ratchet wheels 24 and 34. When a print button which is not shown in a figure is pressed, the solenoid SL turns off and the changeover lever 40 rotates to lock the ratchet wheel 34, so the original platen 4 moves forth as shown by an arrow (b). When the original platen 4 moves back to an exposure start position, the cam 50 moves away on the inversible lever 45 and when the solenoid SL is turned on at this point of time, the changeover lever 40 rocks to lock the ratchet wheel 24, so the original platen 4 moves forth as shown by an arrow (a).

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a drive device for stopping and reciprocating the scanning system of a copying machine using a mechanical clutch.
The present invention relates to a scanning system drive device for a copying machine that moves a reciprocally movable scanning system from a standby position to an exposure start position and then moves it forward to perform scanning exposure.

2. Description of the Related Art In general, in a configuration in which a scanning system consisting of a document table or an optical system and an image forming system including a photoreceptor are driven by one drive source, a mechanical clutch is used to transmit the driving force to the scanning system. The scanning system was moved back and forth by appropriately operating the forward and backward clutches.

As mentioned above, in a copying machine where the standby position and the exposure start position are different, it is necessary to stop the scanning system in the middle of the movement range after the scanning exposure is completed, and as a means for this, for example, a forward clutch and a backward clutch are used. Some were equipped with a solenoid that moved the clutch, and another that oscillated the lever to maintain the clutch in a neutral state.

Problems to be Solved by the InventionHowever, in the above-mentioned systems, two solenoids are required, which leads to high costs.

If an attempt was made to form the above-mentioned neutral state using only the cam member provided in the scanning system, the neutral state would be created by the cam member even during scanning movement, since the standby position is located in the middle of the scanning system movement range. This causes the inconvenience that normal scanning exposure cannot be performed.

The present invention aims to solve the above problems.

Means for Solving the Problems The present invention, as a means for solving the above-mentioned problems, provides a forward clutch that transmits a driving force in the forward direction to the scanning system, and a forward clutch that transmits the driving force in the backward direction to the scanning system. a switching lever that is swingably provided and that operates one of the clutches by engaging with either one of the clutches, a driving means that swings the switching lever, and a switching lever that is swingably provided to operate one of the clutches. A retractable lever is provided so as to be swingable on the lever, and its swinging in the backward movement direction is regulated and is biased in the backward movement direction. a cam that slides into contact with the tip of the retractable lever to maintain the switching lever in a neutral state in which it does not engage with the 01-shifted clutch, and swings the retractable lever in the forward direction as the scanning system moves forward; It is prepared.

Example Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

FIG. 7 shows a copying machine to which the present invention is applied. This is a copying machine with a movable document table in which an optical system consisting of a lens array (2) and a light source (3) is fixed approximately at the center of the main body (1). It is.

The document table (4), which supports the document (0) on its upper surface, can be moved forward in the direction of the arrow (a1) and backward in the direction of the arrow (b1) by a driving means, which will be described later. When the print button (not shown) is pressed, the printer moves back in the direction of the arrow (b1) until it reaches the exposure start position where the leading edge of the document (0) is above the lens array (2), as shown by the broken line. After moving, press the arrow (a) to the position indicated by the dashed line.
direction, and scans and exposes the image of the document (0) onto the photosensitive drum (5) rotating in the direction of arrow C1.

After the scanning exposure is completed, the document table (4) moves back again and stops at the standby position.

On the other hand, around the photosensitive drum (5), a cleaning device 11t6+, an eraser 17) + charger (8), and a developing device (9) are provided, and these known image forming devices are used to clean the photosensitive drum (5). 5) The toner image formed on the surface is transferred by the transfer charger 11 onto the copy paper conveyed from the paper feeding section (101), fixed by the fixing device (17J), and then discharged onto the tray 131.

Figures 1 and 2 show the drive device, which is the main part of the present invention.
4), the driving force is transmitted via the rack gear +15) provided on the lower surface thereof and the transmission gear (16).

The transmission gear (16) meshes with the forward gear ■, and the forward gear ■ meshes with the backward gear ■, and both gears ■ and ■ are each rotatably provided with respect to the main body (1). Axis (21)
, +31). Axis txn, +3
11 is constantly marked with an arrow (d) by a drive source (not shown).
, fe), and a forward clutch and a backward clutch (support) that transmit the driving force to the shafts 211 and t3υ are provided.

The forward clutch and the backward clutch (to) are windmills (2)
.

(The round and kick spring base, (to) are loosely fitted to the 6υ), and by locking (to) of the wind turbine, the kick spring (+35) is tightened and the drive gear ( It transmits the driving force of (3) and (3) to the shafts (21) and (311).

Note that the configurations of the forward clutch (23) and the backward clutch are already known, so detailed explanation thereof will be omitted.

Between the forward clutch 123) and the backward clutch (33), there is a first pawl + that engages with the wind turbine example of the forward clutch (23).
411 and a double-acting clutch (the second one that engages with the windmill)
A switching lever (40) having a pawl (O) is provided so as to be able to swing to operate either of the clutches. (The arrow (44J) is always biased in one direction (see Figure 3), and the tension/id (S
L), the opposite arrow (f1
It is possible to rotate in the direction. The transmission lever +17) is
It is installed so that it can swing around the axis, and one end is connected to a solenoid (
SL) and a switching lever (4G) at the other end.
The pin (17a) is provided with a pin (17a) that is in sliding contact with the solenoid (SL) and transmits the driving force of the solenoid (SL).

A retractable lever (451) is provided in a swingable manner at the end of the switching lever (shaft end) opposite to the claw (4υ1.4"IJ) with respect to the retractable lever (a is the axis (
The stopper fixed to the swing lever +401 is biased in the backward movement direction by the coil spring ((to) wound around the coil spring ((to) It is maintained in a good condition.

On the other hand, a cam ■ having a length in the reciprocating direction is fixed on the lower surface of the document table (4) above the retractable lever (451), and this cam ω indicates that the document table (4) is at the exposure start position ( The relationship between the thickness of the cam ω in Fig. 2 and the length of the retractable lever (451) is such that when the switching lever (41 swings in the direction opposite to arrow (f)), the tip (45a) of the retractable lever (451) slides. When the switching lever (a claw (4υ,
(O is set so that it is in a neutral state in which neither clutch is engaged.

Next, the operation will be explained using FIGS. 3 to 6.

In this embodiment, the solenoid (SL) is controlled on and off by a signal from a microcomputer that controls the entire copying machine.

In the standby state, the solenoid (SL) is on and the third
As shown in the figure, the tip of the retractable lever (451)
remains in contact with the sliding surface (50a) of the cam ω.

When the print button (not shown) is pressed, the solenoid (
SL) is turned off, and as shown in Fig. 4, the switching lever (Soku) rotates in the direction of the arrow to lock the double-acting clutch ((2)), so the document table (4) moves in the direction of the arrow ( b) Return to direction.

When the document table (4) returns to the exposure start position, the cam ■ has been retracted from above the retractable lever.
When the solenoid (SL) is turned on at this point, the switching lever swings in the direction of the arrow to lock the windmill of the forward clutch, as shown in Figure 5.
4) moves forward in the direction of arrow (a). At this time, the retractable lever (a) protrudes into the traveling path of the cam ω, but is pushed by the inclined surface (50b) at the tip of the cam II and is pushed down in the forward direction as shown in Figure 6. Therefore, the forward movement of the document table (4) is not affected.

When the solenoid (SL) is turned off when the document table (4) has moved forward and the scanning exposure has been completed, the switching lever (401) swings again as shown in FIG. (To lock the circle, the document table (4) moves back toward the standby position.

When the solenoid (SL) is turned on when the document table (4) returns to the standby position, the switching lever (a) automatically switches to the tip (451) of the retractable lever (451) as shown in Figure 3.
Since a) comes into sliding contact with the sliding surface (50a) of the cam (2), the switching lever (vertical) is in a neutral state in which it does not engage with any clutch cam (to), and the document table (4) stops.

Note that the means for turning on and off the solenoid may be based on input from a switch provided on the movement path of the document table, or a signal from an encoder provided coaxially with the transmission gear.

In addition, the cam has a sliding surface above the retractable lever when the document table is in the standby position, and has a long sliding surface that is retracted from above the retractable lever when the document table is in the exposure start position. If so, it can be selected as appropriate.

For example, by providing a cam with an intermittently sliding contact surface, the moving distance can be changed depending on the document size, and the document table can be moved to any position and stopped, which is not possible in the erasing machine. The present invention is not limited to D) in which the cylindrical surface is used, but is also applicable to, for example, an optical system that scans and exposes the GL of a microfilm.

Effects of the Invention As is clear from the above description, the present invention provides a cam that is movable integrally with the scanning system and a retractable lever on the switching lever, so that only one lever/id is used. The scanning system can be moved back and forth and stopped.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing one embodiment of the present invention, Fig. 2 is a perspective view showing the relationship between the foldable lever and the switching lever, and Figs. 3 to 6 are explanatory diagrams of the operation of the embodiment of the present invention. , FIG. 7 is a schematic configuration diagram showing a copying machine to which the present invention is applied. (4)...Document table (scanning system), (1η...transmission lever (drive means),...forward clutch, (to)...
Double-acting clutch, (upward...switching lever, (451...
・Foldable lever, (45a)...Foldable lever tip,
(a...Stopper, Ne...Coil spring, ω...
Cam, (SL)... Solenoid (driving means). Applicant Minolta Camera Co., Ltd. Figure 2 jlI3 Figure 4 jlI5! igI 136 figure

Claims (1)

[Scope of Claims] 1. In a copying machine in which a scanning system provided to be reciprocally movable is moved back from a standby position to an exposure start position and then moved forward to perform scanning exposure, the scanning system is moved in the forward direction. a forward clutch that transmits a driving force in the forward direction, and a double clutch that transmits a driving force in the backward direction to the scanning system; a switching lever for actuating the clutch; a drive means for swinging the switching lever; and a driving means for swinging the switching lever, which is swingably provided on the switching lever, is regulated from swinging in the backward direction, and is biased in the backward direction. a retractable lever provided so as to be movable integrally with the scanning system and slidably contact the tip of the retractable lever to maintain the switching lever in a neutral state in which it is not engaged with any clutch; A scanning system drive device comprising: a cam that swings the retractable lever in the forward movement direction as the scanning system moves forward.