JPS6129829A - Original exposure scanner - Google Patents

Abstract

PURPOSE:To shorten the scanning time by reducing the scan length in the second speed VL as much as possible because the scan length in the second speed VL is long normally to spend a long time in scanning. CONSTITUTION:A temporarily stopped exposure lamp 10 starts returning and is fed back to a reference position Pr in the first speed VH, and at this time, a deceleration start distance dH is calculated by a distance dL of scanning in the second speed VL and is set to a position counter 63. When the exposure lamp 10 reaches a point Pa, a motor 59 is braked until the scanning speed becomes the second speed VL, and the position counter 63 is cleared to start measuring another distance dL after it becomes the second speed VL. The motor is braked thereafter until the exposure lamp 10 is stopped. Thus, a high-speed original exposure scanner superior in adaptability to secular change is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION 0) Industrial Field of Application The present invention relates to a document optical scanning device that can be used in copying machines, facsimile machines, document filing devices, and the like.

First Conventional Technology Conventionally, motor control devices have been used to accurately stop moving objects such as document exposure and scanning devices at fixed positions.
Special Publication No. 51-44724.

Special Publication No. 52-47129, Special Publication No. 53-3428
The method shown in Publication No. 4 and the like is already known.

These control devices accurately stop a moving object at a fixed position by speeding up a motor that is rotating at a high speed, causing it to once rotate at a low speed, and then stopping it.

Figure 2 is a graph showing the relationship between speed and scanning distance when this conventional technique is applied to a document exposure and scanning device. This figure shows the scanning state during the backward movement of the original exposure scanning means (specifically, the exposure lamp and the movable hook), and one point Pa is @1.
One predetermined position pb represents the predetermined position of @2.

Further, one point Pa represents a stop position (that is, a forward movement start position M).

Means for detecting the position of the document exposure/scanning means, for example, a microswitch, is provided at points Pa and Pb.

As can be seen from this figure, when the original exposure scanning means starts backward movement and returns to point pa at the first speed VB,
Deceleration is started, and the backward motion is continued at a speed VL of 1g2. Then, when it returns at point pb-1, it is decelerated again and stops at point 1 Pa. Here, the distance from point P1 to point pb is d, the distance from the first speed v8 to the speed vL of @2 is dHL, and the distance from the speed yt of $2 to the speed change to 0 (stop position) is Let the distance be d8.

In the conventional apparatus as described above, since the mechanical resistance of the sliding part between the document exposure scanning means and its supporting member changes over time, (1'HQ changes over time. Even if a change occurs, it was necessary to set d longer than necessary in advance so that the distance (1-+IHL) scanned at the speed vL of '@2 would not become less than 0.

(c) Problems to be solved by the invention As mentioned above, in the conventional technology, d was set longer than necessary, so if dH,tll, was short,
The scanning distance at the slow speed VW of 1 g2 became long, and accordingly, it took a long time to open during scanning. Therefore, when this document exposure and scanning device is employed in a copying machine, there is a problem in that the copying efficiency becomes low.

The present invention has been made in view of the problems of the prior art, and the second speed yt is low.

The purpose of this is to shorten the scanning distance and scanning time as much as possible.

B) Means for Solving the Problems The present invention provides means for detecting the position of the exposure scanning means, and the exposure scanning means scanning at a first speed reaches a first predetermined position. When this is detected, deceleration is started, and scanning is continued at a speed of 182 lower than the first speed, and when it is detected that the second predetermined position has been reached, deceleration is started again. In an original exposure scanning device that stops at a predetermined position.

Scanning distance I at the second speed! LLt- storage means, means for setting a distance aX shorter than this distance + LL, and means for comparing and calculating this distance aX and the distance eLL, and in the case of multiple exposure scans, the distance dX
and the previously stored distance aL is calculated, and during the scanning, the exposure scanning means continues scanning at a speed of sl by a distance eLH from the first predetermined position, and deceleration is performed. 1. A document exposure and scanning device characterized in that the document exposure and scanning device is configured to be started.

(E) Function In the present invention, when exposure scanning is performed multiple times, a distance NeLH that is the difference between the distance aX and the previously stored distance dL is calculated, and at the time of the scanning, the exposure scanning means Since deceleration starts at a position where scanning is continued at a speed of distance (LH'$1) from a predetermined position of , the speed of 181 v!
Even if the distance dHL from I to the speed vL of 182 changes, the distance ax scanned at the second speed vL is always constant. Therefore, by setting this distance aX short.

The overall scan time is reduced.

(f) Embodiment FIG. 3 is a perspective view showing an electronic copying machine in which the present invention is implemented, and FIG. 4 is a front view showing its internal structure. Following these figures, the structure of this electronic copying machine will first be explained.

(1) is the copying machine body, and on the top of this copying machine body.

A manuscript table (2) made of a transparent glass plate is permanently installed.

An automatic document feeder (3) is mounted on the top of the document table (2) so as to be openable and closable with hinges (4). On the right side of this automatic document feeder (3), there is a document (
5) is provided, and a tray (7) on which the copied original is placed is provided on the left side.

(8)... are rollers that transport the original (5), (9)
is a belt.

9. An exposure lamp OD serving as an exposure and scanning means for the original is provided below the original table (2) so as to be movable in the left-right direction. A reflecting mirror ULL whose cross section is in the shape of a column is attached to this exposure kumpu (11).
A first movable mirror 0 is fixed to the mirror il).

When the exposure lamp tlo) scans forward to the right, the document (5) is exposed to slit μ light. In addition, exposure lamp a1
When scanning backward to the left, the original (5) is not exposed. The relationship between the speed of the exposure lamp (111!) and the scanning distance will be described later.

03Q41, a pair of second arms that reflect the original image reflected by the first movable mirror aperture 2 toward the imaging lens 09 again.
It is a movable mirror. This second movable mirror (13041) moves the exposure lamp aI' at a speed of % of the scanning speed of the exposure pump 01.
Move in the same direction as Il. It should be noted that the imaging lens a9 is constituted by a zoom lens that can change the copying magnification.

To the right of the imaging lens 051, this lens (151
A fixed reflection anη is provided to reflect the original image transmitted through the photoreceptor drum (IIEI). aυ is an infrared absorption filter.

Upstream of the exposure position of the photoreceptor drum (16), there is a site toilet slump (4) for removing (site erasing) the electric charge on the portion of the photoreceptor drum 161 corresponding to the side edge of the copy paper a9. is provided. On the upstream side of this site toilet slump (a), there is a photoreceptor drum (161
A charging corotron circle is fixedly installed to uniformly charge the battery positively (approximately 600V).

On the downstream side of the exposure position of the photoreceptor drum fie, a charging corotron Q1), an exposure lamp (II, and an imaging lens Q
A developing device Q'5 for developing the electrostatic latent image formed in step 51 with toner is provided. This developing device (
21 is provided with a screw conveyor (23C24) that stirs the carrier and toner. (C) is a toner storage container that supplies toner to the developing device (C).

It is configured to be able to swing back and forth about the support shaft (A) as a fulcrum.

A transfer corotron for transferring the toner image on the photoreceptor drum onto copy paper is provided downstream of the developing device, and a photoreceptor drum (1G A separating corotron (to) for separating copy paper (1 (I) from
(281 is configured so that it can approach and separate from the photoreceptor drum ttS as a unit.

The holder is a lower paper feed cassette that is removably attached to the inner bottom of the copying machine main body (1), and holds AS size copy paper A9.
is loaded and stored. A compression spring (7) for pressing the copy paper 0 upward and a support plate c311 are provided at the inner bottom of the paper feed cassette handle, and are rotatably provided above the downstream edge of the paper feed cassette handle. The uppermost copy sheet a1 is pressed against the sheet feed roller 0 which is located at the top of the sheet. (l is an upper paper feed cassette similar to the above paper feed cassette (29), and A4 size copy paper αe is loaded and stored inside. (L) is a manual paper feed tray that is rotated one clockwise direction. This makes it possible to feed paper manually.Please note that the main body (1) of the copying machine has:

A sensor (not shown) is provided to detect the size of the copy paper H in the paper feed cassette 4c13.

Along the photosensitive drum (161), on the downstream side (upper left in the figure) of the transfer corotron (c), a cleaning device @G1 is provided to remove toner that has not been transferred and remains on the photosensitive drum +16i. This cleaning device (G) includes a rubber blade (2) for scraping off residual toner on the photoreceptor drum Oe, and a toner storage box 67) for discharging the residual toner scraped off by this blade (2). A screw conveyor (toward) is installed inside.

Also, on the upstream side of this cleaning device (c).

A static elimination lamp G1 is provided for removing the accumulated charge on the photoreceptor drum Ue, and the charging corotron circle is located downstream of this static elimination lamp (toward).

On the horizontal downstream side of the separation corotron (c),
Copy paper α9t fixed fixing device (・
A vacuum conveyor (4I) is provided for conveying to 1■.

The fixing device (4G) has a heat roll (4th floor) with a built-in heater (43) and a pressure roll 04 (which is pressed by this heat roll (43)), and the unfixed toner is stored in both rolls (4: , 1GI4) to fix it on the copy paper 0. (451 (46) is a pair of paper ejection rollers that ejects the copy paper member after fixing onto the paper ejection tray (41). Silicone oil is supplied to the heating roller (43). It is an oil supply member.

(49 is the control box in which the control parts group is installed,
(51) is an exhaust fan. Also, (52)...
・ is a numeric keypad for setting the number of copies.

Next, the exposure scanning means, which is the main part of the present invention, will be explained. In FIG. 4, along the scanning locus of the concave exposure lamp,
Microswitches PO and P that detect this exposure lamp 4
r, pb, and po are provided, and the switch po is provided at the stop position (also the forward movement start position) of the exposure lamp OI, and the switch po is provided at the forward movement completion position (also the backward movement start position). There is. Further, the switch Pr is provided at a position (hereinafter referred to as the reference position) where the deceleration starts from the speed Va of @1 to the second speed ML during the first return movement, and the switch p'b is provided at the position where the deceleration starts from the speed Va of @1 to the second speed ML. 'It is provided at the position where deceleration starts again from VL.

Figure @1 is a graph showing the relationship between the speed of the exposure lamp OI and the backward scanning distance in this embodiment, where the vertical axis represents the speed and the horizontal axis represents the backward scanning distance. Here the points po, pr, pb
Spa is the microswitch po, pr, pb, po
Corresponding to the position, one point Pr represents the predetermined position # of @1, and one point pb represents the position before the second predetermined position. When performing multiple optical scans of the same area, the point pa is
It shows the position at which deceleration starts from the first speed vi to the speed yt @2.

In this figure, the distance from point Pr to point P11 is d, and the distance scanned at the second speed during the first return movement is dlI, point P? ) to point pc is a
B represents the distance m from one point Pr to point Pa as dH, and the second
Second speed V T from point pa during the subsequent return movements
Distance 1 to reach i? dHT, J! The distance scanned at the speed VL of 2 is expressed as dX. Further, the one-dot line indicates the first scanning state of the button, and the solid line indicates the second scanning state.

Here, to explain the case where multiple exposure scans are performed, 1. For example, the distance 6 L n -1 is the value measured during the previous backward movement, and the distance dHn-1 is the distance from point Pr to point pm during the previous backward movement. , Ilx are set to constant values, dHn during the scanning is calculated using the following equation.

l Hn =d Hn-1+l L n-1-(l
Therefore, when performing multiple exposure scans, each time -scan is repeated, ΔdH=dLn-1-dX=dHn-dHn-1
will be corrected only.

FIG. 5 is a plot diagram showing an overview of the control system of this embodiment.
55) is cpo, (54) is various types of memory.

and are mutually connected via a pass line (55).

In addition, microswitches Pa, Pb, as position sensors,
Pr is I/O baud) (56) to pass line (
55), and a motor speed (exposure lamp speed) detection circuit (5B) is connected to this pass line (55) via another I10 port (57). An encoder (60) is connected to the rotating shaft of the motor (59), and the output from this encoder (60) is sent to a timer (62) and a position counter (62) via a motor drive circuit (61).
63) and the motor speed detection circuit (58).

Next, the operation of this embodiment will be explained based on the flowchart of FIG.

The exposure lamp 11α, which once stopped at one point PO after completing the exposure scan in the forward movement, starts the backward movement and returns to the reference position (point Pr) at the first speed Va.

At this point, the deceleration start distance alt-, the previous @2 speed V
This distance (L) is calculated by the distance 11L scanned by L.
H is set in the position counter (66).

And I! When the optical lap OI reaches point P1, the motor (59)
When the brake is applied and this speed reaches the second speed VL, the position counter (65) is cleared and measurement of a new distance eLL is started. After that, exposure lamp a
1 reaches the deceleration start position (point pb) again, the contents of the position counter (63) are read and the distance +LL is measured, and i! The brakes are applied until the Hikari-up crew comes to a stop. The distance +LL measured here is stored in the memory (54) as data for calculating the distance dH during the first backward scan.

In this embodiment, the distance (IH) is changed only during the backward movement, but this distance (IH) may be changed during the forward movement.

Also, I! An encoder (60) connected to the motor (59) is used as a sensor for detecting the position of the light beam (11) instead of the microswitches pa, pb, and pr arranged along this scanning trajectory. You may use it.

Further, the present invention can also be applied to an original exposure/scanning device in which an exposure lamp is fixedly installed and an original table is scanned.

(G) Effects of the Invention The present invention includes a means for storing a scanning distance dL at an i82 speed, a means for setting a distance dX shorter than this distance aL, and a comparison operation between this distance +LX and the distance (il). means, and in the case of multiple exposure scans, the distance a
A distance dH, which is the difference between Therefore, when scanning is performed multiple times, the distance to be scanned at high speed during the second and subsequent scans becomes longer. Therefore, the entire scanning time can be shortened.

Furthermore, even if the mechanical resistance of the sliding portion between the document exposure scanning means and its support member changes over time and the distance d)(L changes), this change can be accommodated.

Therefore, it is possible to realize a document exposure and scanning device that is high-speed and highly adaptable to changes over time.

[Brief explanation of the drawing]

Figure @1 shows an embodiment of the present invention. ! ! FIG. 2 is a graph representing the relationship 8) between the backward scanning speed of the optical scanning means and the position, and FIG. 2 is a graph corresponding to FIG. 1 of the conventional example. Figures 3 to 6 show an embodiment of the present invention; Figure @5 is a perspective view;
Figure 184 is an internal configuration diagram, Figure @5 is a clock diagram, and Figure 6 is a flowchart. (1)...Copying machine body, (II...Exposure lamp,
(59)...Motor, (65)...Position counter
(Pa) (P)) (Pr)...Micro switch (position detection means).

Claims (1)

[Scope of Claims] 1. Means for detecting the position of the exposure scanning means is provided, and it is detected that the exposure scanning means scanning at a first speed has reached a first predetermined position. deceleration is started, scanning is continued at a second speed lower than the first speed, and when it is detected that the second predetermined position has been reached, deceleration is started again and stopped at the predetermined position. In the original exposure scanning device, the following steps are provided: means for storing the scanning distance dL at the second speed, means for setting a distance dX shorter than this distance dL, and means for comparing and calculating this distance dX and the distance dL. is provided, and when performing exposure scanning multiple times, a distance dH that is the difference between the distance dX and the previously stored distance dL is calculated, and at the time of the scanning, the exposure scanning means calculates the distance from the first predetermined position. A document exposure and scanning device characterized in that deceleration is started at a position where scanning is continued at a first speed by dH. 2. The exposure scanning means only performs backward movement after the exposure scanning is completed.
2. The document exposure and scanning device according to claim 1, wherein deceleration is started at a position where backward scanning is continued at the first speed by a distance dH from the first predetermined position. 3. The document exposure and scanning device according to claim 1 or 2, wherein the means for detecting the position of the exposure and scanning means is a sensor provided along the scanning trajectory thereof. 4. The original exposure scanning device according to any one of claims 1 to 4, wherein the means for detecting the position of the exposure scanning device is an encoder attached to a motor that drives the exposure scanning device.