JPS584159A - Optical system driving wire locking device for variable magnification copying machine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an optical system drive wire locking device for a variable magnification copying machine.

A variable magnification copying machine is known in which a scanning optical system such as a mirror for performing optical scanning and an imaging optical system are moved to a position corresponding to a variable magnification ratio with a predetermined optical relationship. ing. FIG. 1 shows an example of a copying machine capable of variable magnification copying of this type, in which an original 0 on a contact glass 10 is optically scanned by a first mirror 1 and an original illumination lamp (not shown). , and second mirror 2,
The drum-shaped photoreceptor 8 is exposed to light via the third mirror 3, the imaging optical system 7, and the fourth mirror 4.

The first carriage 5 carries the first mirror 1 and the document illumination lamp, the second carriage 6 carries the second mirror 2 and the third mirror 3, and the first and second carriages 5 and 6 each carry two mirrors. They move in the directions of the arrows at a speed ratio of :1 to perform optical scanning.

Figure 2 shows the first and second carriages 5.6 each
A first carriage 5 is fixedly engaged with a wire 13 that is passed between defining pulleys 11 and 12, and this is connected to a scanning optical system. It moves in the direction of the arrow via the wire 13 by the driving action of the reciprocating motor 14. On the other hand, movable pulley 15
A second carriage 6 is connected to the second carriage 6, and as is well known, the first and second carriages 5.6 move at a speed ratio of 2:1, respectively, based on the principle of moving and fixed pulleys.

Now, a driving wire 18 is passed to the defining pulleys 16 and 17, and a motor 19 for adjusting the magnification position of the scanning optical system such as the first and second carriages is connected to the fixed pulley 16. For example, a servo motor or the like is used as the motor.

Note that both wires 13 and 18 are composed of one wire, but for convenience, they will be given different names.

When the motor 19 for adjusting the magnification position of the scanning optical system rotates forward and backward,
Along with this, the second carriage 6 moves relative to the first carriage 5 via the drive wire 18 and movable pulley 15, and the carriage 6 is set at a position corresponding to the magnification ratio. In this case, the carriage 6 moves by 1/2 of the amount of movement of the drive wire 18. Further, the imaging optical system 7 shown in FIG. 1 is also set at a position corresponding to the magnification by a separate drive system.

In this case, in Fig. 1, the second carriage 6 is moved in order to satisfy the conjugate length at the time of zooming, but in contrast, the first carriage 5 is displaced. Good too. In addition, in this explanation, for convenience,
The second carriage movement method is applied.

Now, in such a variable power copying machine, the first carriage 5 and the second carriage 7 move at a speed ratio of 2:1, but in this case, the first and second carriages move at a speed ratio of 2:1.
It reciprocates with the speed relationship shown in the figure. Note that the solid line shows the speed relationship of the first carriage 5, and the broken line shows the speed relationship of the second carriage 6.

Here, when the scanning optical system reciprocating motor 14 rotates forward and backward and the first and second carriages reciprocate, for example,
The motor 19 for adjusting the magnification position of the scanning optical system, which is a pulse motor or the like, is kept in a stopped state, and the drive wire 18 is also buttoned so as not to rotate accordingly. However, in reality, the scanning optical system reciprocates in the relationship shown in Figure 3, and at this time, for example, at 9 o'clock when the speed rises, acceleration acts on the scanning optical system, so the driving wire 18 will end up moving.

For example, when a pulse motor is used as the motor for adjusting the magnification position of the scanning optical system, when the pulse motor is stopped, disturbance torque, for example, the motor 14 for reciprocating the scanning optical system, is generated due to the function of the pulse motor. The motor is in a state where it is easy to rotate due to the generated torque, and if the motor 19 rotates by a predetermined angle due to the disturbance torque, the motor that has been controlled to stop tries to return to its original position, and eventually, This will give vibration to the load system. This point applies not only when changing the magnification, but also when magnifying the image at the same magnification. This phenomenon is particularly likely to occur when the speed of the scanning optical system is rising, and when the drive wire vibrates, this imaging propagates to the scanning optical system, resulting in disturbances in the copied image.

An object of the present invention is to provide an optical system drive wire locking device that can eliminate such problems. 1. FIG. 4 shows a drive wire locking device 21 according to one embodiment of the present invention, and this device 21 is provided, for example, at the lower part of the wire as shown in FIG. Note that FIG. 4 is a view seen from the direction of arrow A in FIG. 2.

In FIGS. 4 and 5, a magnetic plate 22 which is long to some extent with respect to the wire tensioning direction is attached to the drive wire 18. In this embodiment, the magnetic plate 22 is fixed to the drive wire 18 by caulking or the like.

An electromagnet 23 is installed opposite to the left side of the magnetic plate 22, and this electromagnet 23 is excited when the scanning optical system reciprocates. is electromagnetically attracted and the drive wire 18 is locked. Also, when adjusting the scanning optical system to the variable magnification position,
The electromagnet is in this de-energized state, and the magnetic plate 2
2 is remote from the electromagnet to allow movement of the drive wire 18.

Since the drive wire 18 is locked when copying is actually performed, it is possible to prevent the wire from vibrating, thereby avoiding the problem of disturbing the copied image. I can do it. In FIG. 5, the magnetic plate 22 is designed to move in the direction of the arrow when changing the magnification. In this case, the magnetic plate 22 is attached to a fixed electromagnet 23. Their lengths are determined so that they always face each other. In other words, the electromagnet 23 is always relatively placed within the range of the movement stroke of the magnetic plate 22.

In addition, in FIG. 4, by attaching a stopper member 24 facing the right plate portion of the magnetic plate 22 to the electromagnet 23, the rotation prevention function of the magnetic plate 22 itself can be achieved.

By the way, when the electromagnet 23 attracts the magnetic plate 22,
The drive wire 18 is bent with a predetermined tension, but when the electromagnet 23 is turned off in this state, the magnetic plate 22 automatically returns to its original position away from the electromagnet due to the return elasticity of the wire itself. become. That is,
According to this configuration, in order to return the elastic plate 22,
It does not require any means such as springs, and has a special effect in that the structure is extremely simple.

In the embodiment shown in FIG. 4, the electromagnet 23 is provided on one side, but on the other hand, the electromagnets are arranged in a distributed manner facing the left and right plate parts of the magnetic plate 22, so that both electromagnets They may be excited at the same time.

Further, the driving wire 18 is fitted to the magnetic plate 22, and the magnetic plate 22 is arranged opposite to the electromagnet so as not to move in the direction of the wire, and the magnetic plate is attracted by the electromagnet. It may also be a configuration.

FIG. 6 shows a friction plate 27a of a clamping member 27 (see FIG. 7) and a friction plate of a fixed member 28 connected to the friction member 25 by fixing it to the drive wire 18 and energizing the electromagnetic solenoid 26. 28α shows an embodiment in which the friction member 25 is clamped, and even with this configuration, the intended purpose can be achieved.

As described above, according to the present invention, when the scanning optical system is moved, the drive wire for moving and adjusting the scanning optical system to the variable magnification position is locked, so there is no risk of the scanning optical system vibrating. Disturbances in the copied image caused by vibration can be prevented, and since no means for returning the magnetic plate is required, the configuration of this type of apparatus can be further simplified.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a copying machine capable of variable magnification copying used for convenience in applying the present invention, FIG. 2 is a diagram of a configuration of a scanning optical system drive mechanism provided in the copying machine, and FIG. 3 is a diagram showing the correlation between speed and time during reciprocating operation of the scanning optical system,
FIG. 4 is a side view of an optical system drive wire locking device according to one embodiment of the present invention, FIG. 5 is a plan view of the same device, FIG. 6 is a front sectional view of another embodiment, and FIG. 5.6. Scanning optical system, 13. Wire system, 14. FIG.
- Scanning optical system reciprocating motor, 18... Drive wire, 19... Scanning optical system magnification variable position adjustment motor, 22
...Magnetic plate, 23...Electromagnet. 1 person Kabayama 5 P) The 4th cause is Atsushi Ozu 52 Tree? 9

Claims (1)

[Claims] A wire system for reciprocating the scanning optical system to perform optical scanning, a motor for reciprocating the scanning optical system for driving the wire system, and a drive wire connected to the wire system for moving the scanning optical system to a variable magnification position. , a motor for adjusting the magnification position of the scanning optical system that drives the drive wire, a magnetic plate attached to the drive wire, and a motor for reciprocating the scanning optical system. An optical system drive wire locking device for a variable magnification copying machine, comprising an electromagnet that attracts and locks a drive wire connected to the scanning optical system magnification variable position adjustment motor.