JPH073551B2 - Variable copying machine - Google Patents

Description

TECHNICAL FIELD The present invention relates to a variable-magnification copying apparatus.

[Problems to be Solved by Prior Art and Invention]

2. Description of the Related Art In recent years, variable-magnification copying apparatuses whose image magnification can be changed have been widely used. In this variable magnification copying apparatus, an original 2 illuminated by an illuminator 1 is scanned by moving a scanning mirror group 3 in parallel with the original 2, as in the copying machine shown in FIG. It is projected onto the photoconductor 5 through the body 4. Around the photoreceptor 5, a charging device 6, a developing device 7, a transfer / separator 8 and a cleaning device 9 are provided.
Are arranged. The transfer paper 11 is sent from the paper storage table 12 by the paper feed roller 13, and is transferred in synchronization with the toner image onto the photoconductor 5 by the roller 14 to transfer the image. After that, it is sent to the fixing device 16 by the carrying belt 15 and sent to the tray 18 through the discharging device 17.

Conventionally, the lens body 4 is moved to a predetermined position according to the copy magnification when changing the magnification by the lens moving means as shown in FIG. 7, and the mirror group 3 is moved by the mirror driving means for scanning the original.

The mirror drive means includes a drive pulley 23 fixed to the output shaft 22 of the drive motor 21 and a driven pulley 25 rotatably attached to the support frame 24 of the mirror group 3 via the intermediate pulleys 26 and 27 and the wire 28. Are connected by. Above wire
28 is connected to the support fitting 29 of the illuminator 1, and
The position of the mirror group 3 is detected by the sensor 31.

The lens moving means is a lens holder 33 that holds the lens 32.
Is attached to the rail shaft 34 so that it can reciprocate, and the wire is attached to the drive pulley 37 fixed to the output shaft 36 of the drive motor 35.
The wire 38 is wound around the wire 38, and the wire 38 is fixed to the lens holder 33 side via a mounting bracket 39.
One side of the lens holder 33 is supported by the roller 41, and the position of the lens holder 33 is detected by the sensor 42. Also the lens
The focal length of 32 is changed at the same time as the movement of the lens holder 33 by the gear 43 attached to the zoom ring engaging with the rack 44.

As described above, in the conventional variable-magnification copying apparatus, the driving source is provided in each of the mirror driving means and the lens moving means, so that the apparatus is expensive.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a variable-magnification copying apparatus in which the scanning driving means of the original scanning optical means such as a mirror and the driving source of the lens moving means can be shared.

[Means for solving problems]

In order to achieve the above object, the present invention provides first driving means for moving a document scanning means for scanning a document placed on a fixed document table, and light obtained from the document scanned by the document scanning means. In a variable-magnification copying apparatus having a second driving means for moving a lens for projecting light onto a photoconductor according to a change in copying magnification, and a driving source for driving both the first and second driving means, Has a power transmission switching means capable of shutting off power transmission from a power source to the second driving means, and when scanning a document, the power transmission switching means is shut off to power the driving source to the first driving means. When the magnification is changed, the power transmission switching means is set to the transmission state to transmit the power of the drive source to both the first drive means and the second drive means.

〔Example〕

 Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

In FIG. 1 in which the same components as those of the conventional device are shown by the same reference numerals in FIG. 7, a wire 38 connected to move the lens body 4 is wound around a driven pulley 51. By rotating the pulley 51, the lens body 4 is reciprocated. Further, the driven pulley 51 is provided with a gear 52 that rotates integrally.

Further, in the vicinity of the driven pulley 51 and the gear 52,
A lever 53 made of a bow-shaped flat plate is provided so as to be swingable around a shaft 54. The shaft 54 has a drive pulley 55 and a gear.
The 56 is mounted so that it can rotate together. A shaft 57 is provided upright on the lever 53 near the shaft 54, and a gear 58 meshing with the gear 56 is mounted on the shaft 57.
Is rotatably attached. The gear 58 is a lever
It is provided so as to engage with or separate from the gear 52 by swinging 53. Meanwhile, the lever
A spring 59 is hooked on the tip of the gear 53 so as to separate the gear 58 from the gear 52, and normally, the drive force is not transmitted between the gear 58 and the gear 52. There is.

The other end of the lever 53 is connected to the solenoid 61.
It is connected via 62. By energizing the solenoid 61, the lever 53 resists the urging force of the spring 59 and the arrow A
The gear 58 is engaged with the gear 52 by being swung in the direction.

Further, the drive pulley 55 has a mirror driving means (first
The transmission pulley 63 fixed to the drive motor 21)
A timing belt 64 is hung between and, and the drive pulley 55 is rotationally driven by the rotational force of the drive motor 21.

Furthermore, from the connecting portion of the solenoid 61, the shaft 65
Is extended in the horizontal direction, and the shaft 65 is inserted so as to be sandwiched between two leaf springs 66, 66, as shown in FIG. The two leaf springs 66, 66 are overlapped and fixed by a pin 67 at one end side, and are bent so as to open from a middle portion toward the tip side. Then, the tip portion is narrowed again and a high friction member 6 is provided between the two.
The wire 38 is sandwiched with a predetermined pressure via 9,69.
As a result, the wire 38 is braked,
The driven pulley 51 is prevented from rotating. Also,
The shaft 65 is inserted in a wedge state so as to come into pressure contact with the inclined surface portion, and when the shaft 65 is swung together with the lever 53, the leaf spring 66 is expanded or returned to its original narrowed state. It is supposed to be done.

In the variable-magnification copying apparatus having such a configuration, when only the mirror group 3 is moved during scanning of an original, the energization of the solenoid 61 is stopped and the lever 53 is attracted to the spring 59, that is, the gear 58 moves from the gear 52. Keep it separated. Thereby, the drive motor 21 of the mirror drive means
The rotational driving force from the gear is transmitted to the gear 58 through the timing belt 64 and the like, but the driving force is not transmitted to the gear 52. On the other hand, the shaft 65 is rocked together with the lever 53 to the open side (right side in FIG. 2), and the wire 38 is sandwiched between the leaf springs 66. As a result, the lens body 4 is given not only no moving force but also a braking force for stopping it at that position. The braking force allows the lens to be accurately stopped and held at a desired position even when vibration of the machine body such as vibration caused by scanning movement of the mirror group occurs.

Next, when the lens body 4 is moved to change the copy magnification, the solenoid 61 is energized and the lever 53 is moved to the spring.
Swing in the direction of arrow A against the pulling force of 59. As a result, the gear 58 is engaged with the gear 52, and the shaft 65 spreads the leaf spring 66 to release the braking force of the wire 38. Therefore, the rotational driving force of the drive motor 21 is transmitted by the transmission pulley 63, the timing belt 64, the drive pulley 55, the gear 56,
It is transmitted to the driven pulley 51 via the gear 58 and the gear 52,
The lens body 4 is moved by the wire 38. When the solenoid 61 is turned off after moving to the predetermined position, the lens body 4 is stopped at that position.

In the above embodiment, since the mirror group also interlocks when the lens moves, as shown in FIG. 3, the lens body 4 is moved when the mirror group 3 is at the end of the movable range at the start of the lens movement. Then, there is also a device in which the mirror group 3 exceeds the movable range. This can be avoided by the method shown in FIG. First, FIG. 4 (a) shows a movement range during normal mirror scanning. Then, during the copy magnification changing operation, from the state where the mirror group 3 is at the left end, as shown by the broken line in FIG. 4B, first, only the mirror group 3 is moved by an amount corresponding to the movable range of the lens body 4, Then, the lens body 4 is moved. In this case, the mirror group 3 is moved as shown by the solid line in FIG. 4, for example.

It is also possible to stop the mirror group 3 at an appropriate position after forming the final image.

Further, as shown in FIG. 5, the rotational driving force of the drive motor 71 is controlled by the idler gear 74 between the drive pulley 72 on the side of the mirror drive means and the drive pulley 73 on the side of the lens moving means (second drive means). You may make it switch and may transmit selectively. The idler gear 74 is attached to one end of a lever 76 which is swung about a shaft 75, and a solenoid 77 is connected to the other end of the lever 76. The lever 76 is biased by a spring 78 so that the idler gear 74 meshes with the mirror driving means. In this way, the movement of the mirror and the movement of the lens can be performed separately, and the operation shown in FIG. 4 is not necessary.

〔The invention's effect〕

As described above, according to the present invention, the drive source of the first drive means for moving the document scanning means and the drive source of the second drive means for moving the lens according to the change of the copy magnification are made common. Therefore, the structure can be simplified, and the cost of the device can be reduced.

Further, according to the present invention, as described above, the document scanning and the magnification change can be performed by one drive source, and the power transmission to the first driving means for driving the document scanning means is not interrupted even when the magnification is changed, so that the power can be supplied. There is no rattling of the power transmission unit due to transmission and interruption, and smooth document scanning can be achieved.

[Brief description of drawings]

FIG. 1 is a perspective view of an apparatus according to an embodiment of the present invention, and FIG.
The figure is an enlarged front view of the braking device, and FIGS. 3 and 4 (a) and (b) are explanatory views showing the procedure of lens movement, and FIG.
FIG. 6 is a plan view of an apparatus according to another embodiment of the present invention, FIG. 6 is a vertical sectional view of a general copying machine, and FIG. 7 is a perspective view of a conventional apparatus. Explanation of symbols 3 …… Mirror group, 4 …… Lens body 21 …… Drive motor, 32 …… Lens 33 …… Lens holder, 34 …… Rail axis 38 …… Wire 51,55,63,72,73 …… Pulley 52,56,58,74 …… Gear 59,78 …… Spring 61,77 …… Solenoid 64 …… Timing belt 66 …… Leaf spring, 69 …… High friction member

Claims (1)

[Claims] 1. A first driving unit for moving a document scanning unit for scanning a document placed on a fixed document table, and a light beam scanned by the document scanning unit and obtained from the document is projected onto a photoconductor. In a variable-magnification copying apparatus having a second drive unit that moves a lens according to a change in copy magnification and a drive source that drives both the first and second drive units, the variable-power copying apparatus includes: It has a power transmission switching means capable of shutting off power transmission to the driving means, and when scanning a document, the power transmission switching means is turned off to transmit the power of the driving source to the first driving means to change the magnification. In this case, the variable power copying apparatus is characterized in that the power transmission switching means is brought into a transmission state to transmit the power of the drive source to both the first drive means and the second drive means.