JPS5955445A - Copying machine - Google Patents

Abstract

PURPOSE:To make correction by centering on displayed set density, by displaying an exposure value set by a density measurement of an original in automatic adjustment corresponding to the position of a density setting lever in manual density adjustment. CONSTITUTION:In automatic density setting mode, data proportional to the mean value of original density is sample-held by the preliminary scanning of an optical system which measures the original density, then displayed on a density aperture display device 6, and the original is exposed in the next copying operation with the quantity of light of a halogen lamp 14 corresponding to the data. When a user makes a slight level change from automatically set density, a density aperture lever 3 is shifted from a current set position 5' to a position 1' for thicker density or to a position 9' for thinner density; the density is varied stepwise between the positions 1' and 9'. Namely, the user makes the slight change centering on an aperture value corresponding to the original density displayed on the density setting display device 6 by using a density setting lever.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a copying apparatus, and in particular to an apparatus which enables manual fine adjustment in its automatic adjustment.

BACKGROUND ART Conventionally, the density W11 of a copying machine is generally adjusted using a manually variable aperture lever, such as from F/ to F9, or a stepwise selection means, such as "Dark", "Normal", etc.
The choice of ``pale'' made her tj゛.

However, in the case of these manual density adjustments, if the original has a dark background color, such as newspaper, diazo copy paper, color paper, etc., if the density adjustment is set to standard and the copying machine is If the development is 〒-color (e.g. black)
, a phenomenon called "fogging" occurs in which the background color of the original is the same color as the text and the entire surface of the copy paper becomes uniformly smeared, resulting in a blurred copy. On the contrary, in the case of an original with extremely low character density, for example, characters written in N in pencil, a phenomenon occurs in which the characters are skipped.

In order to avoid this, generally, it is recommended to go 51 degrees with a certain degree of anticipation! In the former case, the volume is F g =
F9 (in the latter case, FJ to Fri), or a "light" copy (in the latter case, "dark") copy was already set.

However, even in this case, obtaining an optimal copy requires getting used to it by copying the same type of original multiple times, and this may be the cause of copy errors.

In order to solve this IJ;f'X condition, in recent years,
A copying machine with an automatic density ratio of 1.1 and 1.1 was developed. In this type of apparatus, generally, the density of the original is reduced by 11.1, and the exposure amount is automatically adjusted to 51.1, or the development level of the developing means is automatically adjusted.
Adjustments are made automatically.

In this case, if the background color of the document is detected completely, the density adjustment will be appropriate, but it is very difficult to detect the background color of various types of documents, and in general, Detection of the average density of a document is being carried out. Therefore,
Even when automatic adjustment is performed, it is difficult to cover all types of originals, and copy mistakes occur.

Furthermore, the appropriate density level set by the copying device may be different from the level desired by the user. For these reasons, even in automatic density adjustment copying machines, there are still cases where manual density adjustment is required.

Object The object of the present invention is to solve the above-mentioned conventional copying apparatus i11. The disadvantages of manual concentration adjustment are that although it is possible to finely adjust the concentration, it is necessary to make a prediction based on experiment to some extent, and that automatic f1 degree adjustment requires a certain amount of adjustment. Although proper copies can be obtained for originals in the range of B (), both have their advantages and disadvantages, such as the fact that fine adjustments cannot be made. Another object of the present invention is to provide a copying apparatus configured in a couplet manner so that a user can set and print an automatic density adjustment level for standard-sized manuscripts of the same type.

Example The present invention will be described in detail below with reference to the drawings.

Figure 1 shows the conventional manual density setting, where / is the density setting volume, the number above it is the copy density display, and the dark is the dark copy temporary setting that is generally used. ,? Used when reproducing thin originals such as H pencil drawings in darkness.田 is a light copy setting, and is generally used when the background of a manuscript such as a newspaper or diazo copy has a color, and the background is skipped (2 [shi]) to copy only the text. This is a setting for copying with a normal density of Ll, and the user appropriately moves the density setting volume l between m and [η] depending on the original to obtain a copy with a proper density.

However, in this case, as described above, if this is the first original, there is a strong possibility that incorrect settings will be made and a copy error will occur.

FIG. 2 shows the layout 11 of the operation panel portion related to concentration adjustment of the operation section in one embodiment of the present invention. An example is shown here, as in the case of FIG. 1, where C is a level display of density 8j, manual density at constant volume 3 + # regular copy density. When the manual density setting switch is selected from among the density setting mode selection switches and S with the Jun degree setting lever, a copy of the level corresponding to the density setting volume control is set. On the other hand, when the automatic density setting switch S is selected, the original density measured by a circuit described later is displayed on a display element in the display 6 (for example, L
ED) A/~71, and is used to finely adjust the original density.

7 and g correspond to switching and S, respectively;
This is an indicator (for example, an LED) that indicates that either manual or automatic concentration setting mode has been selected.

FIG. 3 shows another example of the operation unit according to the present invention. Here, instead of the concentration setting volume 3 shown in FIG. ,? A and 3B are provided, and their indicated concentrations are displayed on a display 6, but the rest of the configuration is the same as that shown in FIG. 1 and will not be described here.

FIG. 9 shows a portion of the copying apparatus of the present invention that is used to set the concentration in the cap 1 air circuit, and FIG. 3 is a timing diagram of the portion related to the 1vλ step setting. Figure A shows the original TIIJ&W+9 halogen lamp used in the ':+3 embodiment of the present invention. Output voltage control chill input pressure VLINT of iJ river safety equipment (hereinafter abbreviated as CvIt) vs. C1
7 is a graph showing the characteristics of the 7-gen lighting voltage VO.

Before explaining the operation of the density 1ijE' constant part, each part will be explained.

In FIG. 1, RI is a block showing the control section of the complex
O is a photosensitive drum 10, and a latent image of Jg document/, 2 on the document table // is formed on this photosensitive drum 10. 13 is a moving optical system unit ■・, which scans the original on the document table //, 2 with a halogen lamp /l/, and sends the inverse Q=J light to mirrors /S and /6A. Photosensitive drum/θ
lead upwards. The symbols /ri, 1g, /9 and 20 are respectively the meter units for the formation of latent f-bands, and they are respectively 1-band 11-hair, a-blow charge, and V-band 'tl.
lOJ: This is for pre-static charge removal. , 2/ is each '4
1) Electric appliances 17~. This is a high-voltage power supply unit that supplies high voltage to 2θ, and its operation timing is controlled by a signal from the control unit W. Motor 1.2J, which prevents the photosensitive drum from rotating, transmits the drive of motor 4.2 to optical system unit /J, and this optical system unit /3
Clutch 1.21/ is a clutch that similarly advances the optical system unit /J in the backward direction B.

, 2 left is a measurement probe for measuring the latent image potential on the H8 optical drum 10, 2 is a measurement circuit for latent image i11, and the probe measures the latent image potential at a predetermined timing by a signal from the control circuit 9. The density signal is output according to the original.

Amount of powder, 27. ．． 2g and ywa are the arithmetic arithmetic amplification axis numbers (hereinafter referred to as operational amplifiers), 30 is the setting level of the density print lever 3 in the manual density adjustment mode, and the exposure level according to the measured value of the original density in the automatic density adjustment mode, p Circuit block 1. Determines the level of the output of the Mari operational amplifier 2g, selects one display element in the aperture indicator 6, and uses it to fish.1. ? / is a stabilized power supply for a halogen lamp /l, which has the input/output characteristics shown in FIG. 6, for example. code, 3.2,
3J, 3G, and 3M Electromagnetic RelaysNext, the operation of the equipment shown in the first figure will be explained.

When the user selects manual concentration setting, the user first presses the manual concentration selection switch, and that fact is read into the control section, and the mode selections 1 to 3 (3S) are selected. !
! The mode is switched to the concentration setting mode (NO side in the figure), and the LED 7 lights up to indicate that it is the manual concentration setting mode. At the same time, CVR? / output control terminal is connected to the output of operational amplifier 29. In addition, the voltage of the sliding contact of the concentration setting volume 3 (point ■ in the figure) is applied to the relay via the NC contact of /(,,?,2), the CO contact, and the resistor R,2 to the inverting input θ of the operational amplifier Taku. Connected to the terminal. As a result, the voltages Vl and INT applied to the output control terminal of CvR (points marked ■ in the figure) vary within the following range. operational amplifier, 2
9 forms an adder circuit with resistors It/, Rλ and R3. Here, by making the values of these resistors R/, R,', and R3 all equal, the input voltage -y applied to the resistor R/, the input voltage V The following relationship holds true between the output voltage (in this case VLt)aT).

■ Vy, violet NT = (+, u, +v■) In other words,
For VLINT, operate the concentration setting volume 3 to change the voltage at the 0 point from +- to -V (from 0 to 1 on the concentration level display).
- from mouth)! By changing with
If INT = o,, [Zl (7) then NihaVLI
NT = -1-y% Q (7) if vLINT
= Changes to 10V. Furthermore, due to the change in the VLINT voltage, the halogen inlet voltage changes from Vl in the worst case to V5 and I in the case of [Zl] from the CVR characteristics shown in the figure.
In the case of 11, V9 changes in proportion to the control voltage, and it is possible to obtain a halogen lighting voltage corresponding to the copy density desired by the user.

Next, the case of automatic density setting will be explained.

When the user presses the automatic concentration selection switch S, that fact is read into the control unit and the mode selection relay is set to 4t.
(3, 5') switches to the automatic density setting mode side (NC contact side in the figure), thereby causing the LEDg to light up, indicating that it is the automatic density setting mode.

At the same time, CVR? The output control terminal of / is connected to the relay through the CO and NC contacts of /(,?,,?,) to the output of the operational amplifier, 2g. Also,
Concentration setting volume? The voltage at the sliding contact (the point marked ■ in the figure) is connected to the inverting input e terminal of the operational amplifier 2g via the resistor R6. now ,! ! ! 4 degrees Ljj25:
Assuming that jJ volume 3 is at the standard concentration 1 position, I:, 0 point pressure & J: OV, the output to operational amplifier 2 is responsible, and the output of operational amplifier λ input via resistor R7 (voltage at point 0 in the figure).

In this way, using the timing chart of t+=+, auto-density crotch h? I will explain about it. When the copying operation is started at instant T1, the motor 2 rotates and the photosensitive drum 10 rotates. At the same time, a high voltage is also applied to each charger (7.1g, /q, and ) by the high-voltage transformer, and an electrostatic charge is applied to the photosensitive drum (.theta.) by a well-known electrophotographic process.

At the same time, the halogen lamp /1 is turned on to start measuring the density of the original /1. At this time, the relay /(,?,2
) is energized and its contact switches from NC to NO.

At the same time, the input to the output control terminal of CVR3/ is cut off from operational amplifier 2g, and relay KII
(, yt) CO contacts and NC contacts, and relay/
The CO contact of (, ?, 2) is connected to the output of the operational amplifier 29 via the NC contact. Furthermore, R,2 of the resistors connected to the inverting input e terminal of the operational amplifier is connected to (7V) through the 00 point and the NC contact.

Since the output is set as V■-O in the above calculation formula, (1) VLINT = -(--+ o ) = Tλ.

This value remains constant while the relay is energized (see 1 in Figure 6).
1 to 15) is constant, and the output voltage Vo of CVH is v
5, that is, it should be fixed at the same value as when setting the factor with the concentration setting volume 3. As a result, while measuring the original density, the amount of light emitted by the halogen lamp remains constant no matter how many measurements are taken.

At the timing of T1, relay 2 (33) is also energized at the same time, and the capacitor C of the lean-pull bold circuit using a Miller integration circuit consisting of the resistor FiR, capacitor C/, operational amplifier λ7, and contact point 3 of the relay is activated. The voltage hold value (-Vfl in the figure) of / is discharged through the resistor I (A-), and the ripple bold circuit a is brought into the seven-hit state. This reset is performed at time 115 of The output of the operational amplifier 27 at this time is oV.At T3, the light intensity of the halogen lamp/4' has risen.
At the timing of , the optical system advance lever J3 is driven, and the optical system unit/3 starts moving forward in the X direction (1 direction F).

As a result, the optical image of the original 7.2 is reflected by the mirror /S and 76, and enters the 0 point of the photosensitive drum /θ, and begins to form an electrostatic latent image of the original /2. In this state, at timing T4 when the electrostatic latent image of a predetermined portion of the document/co on the document table ll reaches the measurement position 0 point of the surface potential sensor J.
,? (34t) is energized, and the output of the surface potential measuring circuit, 2B, is sent to the relay. (It is input to the above-mentioned ripple hold circuit through the CO contact and No contact of J40. In the sample hold circuit using the Miller integration circuit of the operational amplifier 27, the above-mentioned surface potential is It is integrated.

Then, at timing T5, when the surface potential of the electrostatic latent image in a predetermined range of the document/co is sampled, relay 3 (31
/,) decreases in strength. The change in the voltage at the output point 0 of the sample bold circuit in this state decreases from oV, as shown from T3 to T5 in the timing chart of FIG. S, and reaches the value of v2 at T5. Naturally, the final value of the voltage at the 0 point varies depending on the average density of the original, and the darker the original, the lower the voltage.

As described above, when the sampling of the average value of the density in the predetermined range of document/2 is completed, the forward clutch is turned off at timing T6, and the halogen lamp/lI is turned off.
Instead, the reverse Kradico 3 is driven and the optical system unit)/
3 starts moving backwards. Then, at timing T7 immediately after the start of reverse movement, /(,?,2) is deenergized to the relay. As a result, the output control terminal of CVR3/ is the relay Kl.
It is connected to the output of the operational amplifier 2g via the CO contact and the NC contact of (, ?). This operational amplifier at forms an adder circuit together with resistors R4, R and R.
The resistance value of resistor R7, Rg is R1 The resistance value of resistor R6 is n
If X11, then the output of the operational amplifier 2g (in this case VLINT) will be as follows: the voltage V2 applied to the resistor R6 and the voltage V(i) applied to the resistor R.

Vr, xtJr--(V■10-V■) In other words, VLrh+7 is the original (11 concentration voltage V■) plus the voltage y■ at t/n of the voltage V■ from the concentration setting volume 3. .Now, if we copy the density setting volume 3 using a newspaper as the original 4715/) with low P>jH, then the output voltage of the -ripple hold circuit V■GJ-V (that is, the operational amplifier at the timing of Tj, 27 ) reached value v2=-v), and Mano: V((
1) Since it is -0, Vj, INT--(-V+-X O) == -1-V
becomes. This 'rl! The pressure value will be the same as when the concentration setting volume 3 is set to the gate, as seen from Guzif in FIG. This makes the background color of the newspaper pop. Also, + to the relay! Via another contact of (,?,!t), this voltage is determined by the level determination circuit block Jθ, and the LEDA! r lights up. In this state, when the optical system unit/3 reaches the home position at timing T8, the reverse clutch 2 is disengaged and the movement of the optical system unit/3 is stopped. At the same time, a halogen lamp/l was used for the main scan of the copy.
I- lights up. The lighting voltage at this time is at timing T1
~・Value controlled by the value zumbling in the concentration measurement of T8 ■9.

Then, at the timing T9 when the light of the halogen lamp /q rises and becomes constant, the optical system forward clutch n is engaged again, and the document /, 1 for copying is scanned until the instant TIO, and at the instant T'to. Disengage the optical system forward clutch 3, turn off the halogen lamp puffer, turn on the optical system reverse clutch, and at the timing Tll when the optical system unit/3 reaches the home position, the optical system reverse clutch,
Cut 2 pieces. If the copy mode is for multiple copies from the same original, the halogen lamp /'I is turned on at instant T11, the optical system forward clutch 23 is engaged again at n time T12, and the process from instant T8 to 'I'll is completed. repeat. In the case of final copy or single copy, do not turn on the halogen lamp with simultaneous Tll, turn on main motor, 2.2, high voltage transformer, 2/ with Tr3 at 1 o'clock, and finish copying. .

As described above, in the present invention, in the automatic density setting mode, the original (6
r1. "Zamble-hold the data proportional to the average value of 4 degrees, display the value on the density aperture display t, and then use the halogen lamp/ray light 1,1 corresponding to the bold data in the following copy routine. First, when the user wishes to change the density level by a little more than that set by the automatic density setting, the density aperture lever J?L - current From the set position of l, shift towards [/j for a darker sound α, and towards 1 for a lighter sound, respectively.
, IZI to [] It is possible to change the density corresponding to i between columns. That is, NF< allows the user to make slight changes using the density setting lever, centering on the embossed candy corresponding to the original density displayed by the density setting display O.

Effects As described above, according to the present invention, the amount of light set by measuring the density of the original during automatic density adjustment is displayed in correspondence with the position of the density setting lever during manual density adjustment, thereby making it easier to use. When a person wants to make a slight correction, he or she can make settings for the correction on the displayed density setting lever, making it possible to perform automatic density adjustment with a function that is extremely easy to operate.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a conventional manual concentration setting volume, and FIG. 2 is an example of an operation unit having a changeover switch for automatic concentration setting and manual concentration setting mode and a concentration setting volume in an embodiment of the present invention. FIG. 3 is a layout diagram showing another example of the operation section using the density change switch, and FIG. 7 is an example of the configuration of a portion particularly related to density adjustment in the circuit of the copying apparatus of the present invention. The circuit diagram shown in FIG.
, KS The figure shows the halogen zinc resin 1! used in the embodiments of the present invention. Tlr, source output conduit) does not show the relationship between the input voltage and the halogen lighting voltage, and is a concave curve 4. '''' r! 1.L n'25ji Horyu, A.
β...Copy concentration display, J...Probability 2. ]1-'J[Setting volume, JA,,7
B...Density change mode, R...Manual density setting switch, Left...Self! +Density setting switch, t...IQ density display, A/--I/...Display element - ri...Manual density setting mode display, g...Auto density setting mode display)): Dimensions , 9... Control unit, 10... Photosensitive drum, ll... J Emperor (1-4 units, 7.2... Document, /3... Moving optical system unit, /4/...・Halogen lamp, /Left, /6...Mirror, /7...Primary charger, 7g...Secondary charger, /9...Transformer VR charger 1 .20...Deleted military Charger, λc...High voltage power supply unit, 22...Motor 1.23...Forward clutch 1.2...Reverse clutch, 5...Latent image potential measurement probe, =λ7;... Latent image TrL position 411) constant 1ij1#
i. 27,. 2g, ,19...operator 1? +! circuit, 3
θ...Display lighting circuit, 3/...Stabilization TIT, 1lliJ, JJ, 3.3
．． ,? +, ,? , t...Relay (K/, ni, 2
．． , 7°K da), R/ -R9...Resistance. Patent applicant Canon Co., Ltd.

Claims (1)

[Claims] Manually adjust copy density? l='4 Hand to guess! 1III θ degree adjustment means, a density detection means for detecting 11° 5 degrees of the document, and the density detection means? A) Automatic density +1', 'J leveling means, copying, and the first mode in which the density is manually adjusted to W1ν so that the appropriate image quality is achieved according to the density of the viewed original. When the second mode for adjusting the throat at ~1j is set to 1%, and when the second mode is set at j'h, the darkness of the copy by the automatic density adjustment means is increased by tJtJ.゛Setゝ/l-+ffJ
TjiJ reporter y when the first mode is selected
Concentration n! 4. The copying device (tj) is provided with a means for displaying the level by J+i5+ with respect to the level by the adjustment means'.