JPS6282878A - Subscanning mechanism - Google Patents

Abstract

PURPOSE:To obtain a subscanning mechanism capable of executing speed changing with fine resolution by a simple means by providing the mechanism with a carrying means satisfying plural subscanning resolution levels. CONSTITUTION:An original inserted from a direction A is carried by carrying rollers 1-4 and discharged in a direction B. During the period, the picture information arrives at a CCD 10 through an illuminatng source 5, a mirror 8 and a lens 9 and is photoelectrically converted by the CCD 10. An one-way bearing is pressed into pulleys 20-23 and inserted into respective rollers 1-4. The pulleys 20, 21 transmit driving force to the rollers 1, 2 at the time of clockwise rotation and the pulleys 22, 23 transmit driving force to the rollers 3, 4 at the time of counterclockwise rotation. At the rotation in the reverse direction, the rollers 1-4 are made free from the pulleys 20-23. When the motor 27 is rotated in the clockwise direction, paper is carried by the rollers 1, 2, and in case of the counterclockwise rotation, the paper is carried by the rollers 3, 4. The resolution of 7.874l/mm is obtained at the carrying of the rollers 1, 2 and the resolution of 7.7l/mm is obtaied at the carrying of the rollers 3, 4.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a sub-scanning mechanism, and more particularly to a sub-scanning mechanism that can switch resolution in the sub-scanning direction and is applicable to devices such as facsimile machines.

(Prior art) CCrTT (International Telegraph and Telephone Consultative Committee) Group 3
(The sub-scanning resolution of the GI[I) device is 3.95// m
m, option is 7.7//mm. As a means of implementation, the conveyance rollers have operated on common data or varied the motor speed. Group 4 of CCITT (GR
') The device has modes such as 200dpi=7.87A/mm. Therefore, since the resolutions are too close, the conveyance roller cannot be used for switching, and a separate conveyance device is used.

When a sub-scanning conveyance means using rollers or the like is determined, a conveyance roller is rotated from a stepping motor to be used via a deceleration system to convey the paper in a predetermined manner. If the speed reduction system uses a timing belt, gears, etc., the number of teeth is an integer, so depending on the selection of the roller diameter, the roller rotation will not reach a predetermined sub-scanning resolution. Therefore, the roller diameter is ultimately changed by a small amount to achieve a predetermined sub-scanning resolution. When changing the sub-scanning resolution, the motor drive frequency is changed. For example, the rotation angle of the stepping motor is 0.9"/pulse, and the vapor speed is 5"/pulse.
m s / line, reduction ratio (1st reduction Z+ "15.
When Zz = 51), r-51/15 = 3.4.
Assuming that one line is fed by four motor pulses, the motor speed is 410.005=800 pps. Sub-scanning resolution is 7.7! ! /mm, the conveyance roller diameter is D-1/7. 7x36010. 9x51/
15xl/πx4=t4.055mm.

Therefore, if the roller diameter is 14.055 mm and the motor is driven at 800 pps, the paper will move at a pitch of 1/7.7 mrn at the above reduction ratio.
,7j! It can be extracted with a resolution of /mm. Also, if the motor speed is 1600pps under the above conditions, the resolution is R-πX14.055XO, 9/360X8X1
5151=1/3.85.

On the other hand, in CCITT's GIV, 200api,
The resolution of 240dpi, 300dpi, and 400dpi is regulated, but if we focus on 200dpi, 2
00dpi=7.8141/mm, whereas in GIV it is 7.71/mm. The difference is 0
．． 174 i! /mm, but if we sub-scan 200dpi+N information using the drive system and conveyance system, then A4 size (
297 mm), the image shrinks by 6.8 mm. The total size is 297x7.7/7.874-297-6.8mm. It is actually very difficult to control this with the number of pulses of the motor.

(Objective) An object of the present invention is to provide a sub-scanning mechanism that enables fine-resolution speed change in a device such as a facsimile by a simple means.

(Structure) In order to achieve the above object, the present invention is characterized in that a sub-scanning mechanism used in a device such as a facsimile is provided with a conveying means that satisfies a plurality of sub-scanning resolutions.

Hereinafter, a detailed explanation will be given based on one embodiment of the present invention.

FIG. 1 is an explanatory diagram showing an embodiment of the conveyance system of the present invention. In the figure, 1, 2, 3.4 are conveyance rollers, 5 is an illumination source, 6 is a document holder, 7 is a reading unit, 8 is a mirror, 9
is a lens, and IO is a C0D (charge coupled device). In this configuration, a document inserted in the direction of arrow A is conveyed by conveyance rollers 1.degree. 2.3.4 and discharged in the direction of arrow B. Meanwhile, an illumination source 5, a mirror 8 and a lens 9
The calligraphy information reaches the CCD10 and is converted into a light source.

FIG. 2 is an explanatory diagram showing another embodiment of the conveyance system. In the figure, 5 is an illumination source, 9 is a lens, 10 is a CCD, 15
is an idler roller, and 16 and 17 are conveyance rollers.

In this configuration, the original enters in the direction of arrow A, is fed by conveyance rollers 16 and 17, and is discharged in the direction of arrow B.

” In the double embodiment shown in FIGS. 1 and 2, when conveyed by conveying rollers 1 and 2, for example, 200 dpi
For example, if the resolution is 7.77!, when conveyed by conveyance rollers 3 and 4, the resolution is 7.77! The resolution is /mm. In the embodiment shown in FIG. 2, the conveyor rollers 16 and 17 have diameters corresponding to their respective resolutions.

The embodiment shown in FIG. 2 has a configuration for reading, but instead of a reading system, a thermal head is brought into pressure contact with an idler roller 15 made of rubber, and a heated recording paper is fed in between. It becomes a recording system and has the same effect.

FIG. 3 shows an embodiment of a drive system corresponding to the conveyance system shown in FIG. 1, in which the same parts as in FIG. 1 are given the same reference numerals. In the figure, 1, 2.degree. 3.4 is a conveyance roller, 20, 21, 22, 23 are pulleys, 24 is a drive roller, 25 is a drive shaft, and 26 is a rotating shaft of a motor 27. In this configuration, one-way bearings (not shown) are press-fitted into the pulleys 20, 21, 22, 23, and each roller 1,
It is inserted at 2°3.4. The pulleys 20, 21 transmit the driving force to the transport roller 1.2 when rotating clockwise, and the pulleys 22, 23 transmit the driving force to the transport roller 3.4 when rotating counterclockwise.

In the opposite direction of rotation, the conveying roller 1°2.3
．． 4 becomes free with respect to the pulleys 20, 21, 22, and 23, and thus becomes an idler that rotates following the drive roller 24. Therefore, when the motor 27 rotates clockwise,
The vapor is sent by conveyor roller 1゜2, while motor 2
When the roller 7 rotates counterclockwise, it is transported by the conveyor rollers 3 and 4.

FIG. 4 shows an embodiment of a drive system corresponding to the conveyance system shown in FIG. 2, in which the same parts as in FIG. 2 are given the same reference numerals. In the figure, 15 is an idler roller, 16
．． 17 is a conveyance roller, 27 is a motor, 30, 31, 32
, 33.34 are gears. In this configuration, the transmission from the motor 27 is via gears 34, 33, 30.31. One-way bearings (not shown) are press-fitted into the gears 30 and 31 so that the transmission is reversed, and the conveying rollers 16 and 17 are connected to the gears 30 and 31, respectively. Therefore, similarly to the embodiment shown in FIG. 3, when the motor 27 rotates clockwise, the conveyance roller 16 is driven. At this time, the idler roller 15 and the conveyance roller 17 rotate following the conveyance roller 16. When the motor 27 rotates counterclockwise, the conveyance roller 17 is driven, and at this time, the idler roller 15 and the conveyance roller 16 rotate following the conveyance roller 17. Therefore, by changing the diameters of the conveyance rollers 16 and 17, two types of Conveyance sub-scanning can be achieved.

In the first embodiment described above, the resolution is 200 dpi = 7.874β/mm when transported by transport rollers 1 and 2, and 7.874β/mm when transported by transport rollers 3 and 4.
A resolution of 71/mm can be obtained. On the other hand, in the second embodiment, the diameter of the conveyance roller is 7.8747
! /mm and 7°7β/mm to obtain various resolutions.

(Effects) As described above, according to the present invention, in order to perform fine resolution switching, the conveying roller as a conveying means having a level close to the sub-scanning resolution is driven by the forward and reverse rotation of the motor. It is possible to provide a sub-scanning mechanism that has the effect that the conveying means can be built into the device and that a plurality of sub-scanning resolutions can be satisfied with a simple means.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing one embodiment of the conveyance system of the sub-scanning mechanism according to the present invention, FIG. 2 is an explanatory diagram showing another embodiment of the conveyance system, and FIG. 3 is the conveyance system shown in FIG. 1. FIG. 4 is an explanatory diagram showing the drive system of the embodiment of the conveyance system shown in FIG. 2. FIG. 1.2, 3.4... Conveyance roller, 16.17... Conveyance roller, 27... Motor. Figure 1 1υ Figure 2

Claims (1)

[Claims] In the sub-scanning mechanism used in devices such as facsimiles,
A sub-scanning mechanism characterized by comprising a conveying means that satisfies a plurality of sub-scanning resolutions.