JPH065411B2 - Image forming device - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to an image forming apparatus such as a color copying machine capable of color copying of a plurality of colors.

[Technical Background of the Invention and Problems Thereof] In recent years, for example, in a copying machine or the like, colorization has progressed, and a two-color color copying machine or the like capable of obtaining a color image other than black has been put into practical use. However, in a conventional color copying machine of this type, a plurality of cartridges in which a developing device and a photoconductor are integrated are prepared and selectively replaced, which is a troublesome operation. Atsuta

Therefore, recently, there has been considered a color copying machine which is provided with a plurality of developing devices capable of performing different developments, respectively, and is capable of performing color copying of various colors by switching the developing devices. However, since this type of copying machine is provided with a plurality of developing devices, it is necessary to accurately know the developer life for each developing device.

[Object of the Invention] The present invention has been made in view of the above circumstances. An object of the present invention is to provide an image in which the developer life can be accurately and easily determined for each developing unit or for each color of the developer. To provide a forming apparatus.

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a first developing means for forming an image on an image bearing member with a first developer and a second developing means different from the first developer. Second present means for forming an image on the image bearing member with the developer, supporting means for supporting the first developing means and the second developing means, and a supporting means supported by the supporting means. Selecting means for selecting one of the first developing means and the second developing means; and if the developing means selected by the selecting means is the first developing means, the first developing means When the developing means selected by the selecting means is the second developing means, the first counting means for counting the first number of times the developing means has executed the developing operation, and the second developing means develops. Second counting means for counting a second number of times the operation is executed, and the first number of times And third counting means for counting a third number of times obtained by adding the second number of times, and any one of the first number of times, the second number of times, and the third number of times. It is provided with a designating means and a display means for displaying the number of times designated by the designating means.

[Embodiment of the Invention] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a two-color color copying machine as an example of an image forming apparatus according to the present invention. That is, reference numeral 1 denotes a copying machine main body, and an upper surface of the main body 1 is provided with a document table 2 which is reciprocally movable in the left-right direction (direction of arrow a in the drawing). Also,
A paper feed cassette 3 is mounted on the right side surface of the main body 1, and a paper discharge tray 4 is mounted on the left side surface thereof. Further, the cassette cover 5 of the paper feed cassette 3 and the manual feed stand 6 for manually feeding the paper P ₂ are provided. Further, a photosensitive drum 7 as an image bearing member is arranged at a substantially central portion of the main body 1. And this photosensitive drum 7
A charging charger 8, an optical system 9, a two-color developing device 10, which will be described later, a transfer charger 11, a peeling charger 12, a cleaning device 13, a charge eliminating lamp 14 and the like are sequentially arranged around the periphery of the device. ing. In the lower part of the main body 1, the paper P ₁ automatically taken out from the paper feeding cassette 3 via the paper feeding roller 15 or the paper P ₂ manually fed from the manual feeding stand 6 is used as the photosensitive drum 7. A sheet conveyance path 1 that leads to the sheet discharge tray 4 via the image forming unit 16 between the transfer charger 11 and the transfer charger 11.
7 are formed. A registration roller 18 is provided on the upstream side of the image forming portion 16 of the paper transport path 17, and a heat roller 19 and a discharge roller 20 as a fixing device are provided on the downstream side.

Here, the optical system 9, an exposure lamp 22 whose back part is surrounded by a reflector 21, mirrors 23 to 26, and a lens 27 are provided.

Then, the photosensitive drum 7 is driven by a drive mechanism (not shown) in the direction of the arrow b in the figure in synchronization with the document table 2. First, an image of a document uniformly charged by the charging charger 8 and uniformly illuminated by the exposure lamp 22 is formed on the photoconductor drum 7 by the optical system 9 to form an electrostatic latent image. To be done. The formed electrostatic latent image is developed by the developing device 10 to be a developer image, and is sent to the transfer charger 11 side. On the other hand, the paper P ₁ that is automatically or manually fed
Alternatively, P ₂ is supplied by the registration roller 18, and the developer image previously formed on the photosensitive drum 7 is transferred by the transfer charger 11. The paper P ₁ (P ₂ ) to which the developer image is transferred is separated from the photoconductor drum 7 by the separation charger 12 and passes through the paper conveyance path 17 to be guided to the heat roller 19, where the transfer image is transferred. After being fused and fixed, the sheet is discharged to the sheet discharge tray 4 by the sheet discharge roller 20. On the other hand, the residual toner left on the photosensitive drum 7 after the developer image is transferred onto the sheet P ₁ (P ₂ ) is cleaned by the cleaning device 1.
3 and the charge elimination lamp 14 erases the residual image on the photoconductor drum 7 to prepare for the next copying operation.

In the body 1, an upper frame and a lower frame (not shown) are pivotally supported at one end via a support shaft (not shown), and the other ends of both frames are at a desired angle, for example, about 30 degrees. It is configured to open to. Each device such as a charging charger 8, an optical system 9, an exposure lamp 22, a developing device 10, a cleaning device 13, and a discharging lamp 14 is attached to the upper frame around the photosensitive drum 7 by appropriate means. Further, the document table 2 and the paper feed roller 15 are also attached to the upper frame, and the upper unit 1A
Are configured. Further, in the lower frame, various mechanisms such as a paper feed cassette 3, a transfer charger 11, a peeling charger 12, a heat roller 19, a paper discharge roller 20, a paper discharge tray 4 and a main motor 28 are provided as appropriate means. Are attached to form a lower unit 1B. After the front cover of the main body 1 is rotated and removed, the front cover of the main body 1 can be opened and closed substantially along the paper transport path 17 of the paper P ₁ (P ₂ ) via a housing opening / closing device (not shown).

Further, 29 is a cleaning blade 30 of the cleaning device 13.
Is a blade solenoid for contacting with and separating from the photosensitive drum 7.

Next, the developing device 10 will be described in detail. Second
As shown in the drawing, the first developing roller 31 ₁ and the second developing roller 311
The developing roller 31 ₂ is provided, and these developing rollers 31 ₁ , 3
Selectively drive ₁₂ to select black or one other color,
For example, color development of red, yellow, blue, green, etc. can be performed. That is, the developing device 10 is divided into a first developing device 32 ₁ including the first developing roller 31 ₁ and a second developing device 32 ₂ including the second developing roller 31 ₂ ,
These first and second developing devices 32 ₁ and 32 ₂ are both attached to and detached from the main body 1. In this case, the first developing unit 32 ₁ of the upper row, the user has drawer obtained easily detachable freely configured and summer upward in the drawing, and the second developing device 3 of the lower
2 ₂ serviceman maintenance, when performing such inspections, and configurations and summer capable of detachably attached to the main body 1. The black developer, which is frequently used, is used by the lower second developing device 32 ₂ , and the color developer is used by the upper first developing device 32 ₁ .

The developing mechanism section 33, which includes the first developing device 32 ₁ , a developing mechanism section 33 ₁ and a developer replenishing section 34 _1.
1 is provided on the sliding contact portion between the developing roller 31 ₁ and the photosensitive drum 7 of the developer magnetic brush 35 ₁ formed on the surface of the developing roller 31 ₁ , that is, on the upstream side of the developing position 36 ₁ . A doctor 37 ₁ for controlling the thickness of the developer magnetic brush 35 ₁ and a developer magnetic brush 3 provided on the downstream side of the developing position 36 _{1 and} on the surface of the developing roller 31 _1.
5 ₁ and scraping, the scraper 39 ₁ for guiding the developer accommodating portion 38 _1, and a developer accommodating portion 38 developer stirring member 40 ₁ housed in ₁ summer configuration and accommodated in the casing 41 in _one. Note that the position corresponding to the upper part of the developing roller 31 ₁ of the casing 41 _1, developer density detector 42 ₁ detects a developer density by detecting a change in magnetic permeability of the developer G ₁ magnetically Has been attached.

Further, the developing roller 31 ₁ is provided in a state where the angle α centered on the straight line L ₂ drawn to a state where the (approximately 51 °) the rotation center relative to the as a horizontal line L ₁ of the photosensitive drum 7 is positioned The magnetic roll 43 ₁ and the sleeve 44 ₁ fitted on the magnetic roll 43 ₁ and rotating clockwise in the drawing. The magnetic roll 43 ₁ has five magnetic pole parts 45 ₁ to 49 ₁ , of which the magnetic pole parts 45 ₁ and 47 are included.
_1, 49 ₁ N-pole, the magnetic pole unit ₄₆ 1, 48 ₁ are summer and S poles, the angle theta ₁ between the magnetic pole portions 45 ₁ and 46 ₁ to about 5
0 °, the angle between the magnetic pole portions 46 ₁ and 47 ₁ is θ ₂ is about 7
1 °, the angle θ ₃ between the magnetic pole portions 47 ₁ and 48 ₁ is about 60
°, the angle theta ₄ between the pole portion 48 ₁ and 49 ₁ to about 60 °
Are set respectively.

Further, the developer replenishing section 34 ₁ has a developer replenishing port 50 ₁
The a Hotsupa 51 ₁ to face the developer accommodating portion 38 ₁ of the developing mechanism 33 _1, the Hotsupa 51 developer supply roller 5 provided in the _first inner and and state for closing the developer supply port 50 ₁
2 ₁ and the developer G on the developer supply roller 52 ₁ side
₁ and summer configuration and having a pair of stirring rollers ₅₃ 1, 53 ₁ to agitate the developer _{G 1} in Hotsupa 51 ₁ to carry.

In addition, the second developing device 32 ₂ is the first developing device 32 described above.
_The basic structure is almost the same as that of the developer replenishing unit 34.
₂ of Hotsupa 51 ₂ the shape and arrangement of the magnetic poles of the developing roller 31 and _second magnetic roll 43 _2, approximately 20 ° further and the mounting position of the developer density detector 42 _2, with narrow accompanying (about 50 mm) The difference is that a scraper 54 having an inclination of is added. Therefore, the other same components are denoted by the reference numerals in which the suffix character of the reference numerals is changed from " ₁ " to " ₂ " and the detailed description is omitted. The developing roller 31 _{and second} magnetic roll 43 ₂ four magnetic pole portions ₄₅ 2-48
It has _two magnetic pole portions ₄₅ 2, 47 ₂ of which N-pole, the magnetic pole unit ₄₆ 2, 48 ₂ and summer and the S-pole, the magnetic pole portion 45 ₂
If the angle theta ₅ is about 78 ° between 46 _2, the angle theta ₆ is approximately 70 ° between the magnetic pole portions 46 ₂ and 47 _2, the magnetic pole portions 47 ₂ and 4
The angle θ ₇ with 8 ₂ is set to about 80 °. The magnetic roll 43 ₂ is provided at an angle β state (about 1 °) and becomes centered on the straight line L ₃ to be pulled to a state is located the center of rotation relative to the as a horizontal line L ₁ of the photosensitive drum 7 There is.

On the other hand, the magnetic rolls 43 ₁ and 43 ₂ of the first developing device 32 ₁ and the second developing device 32 ₂ , respectively, are configured to be rotationally displaceable to a state in which the rotational angle is approximately 25 degrees. , The developing rollers 31 ₁ , 3
1 ₂ developer magnetic brush ₃₅ 1 on the surface, 35 or form _2, and summer to allow or removed. And
By switching the magnetic rolls 43 ₁ and 43 ₂ of the first developing device 32 ₁ and the second developing device 32 ₂ to predetermined positions by a magnetic roll driving means described later, the first developing device 32 ₁ or the second developing device 32 ₂ One of the developing rollers 3
1 _1, 31 only _two of the surface developer magnetic brush ₃₅ 1, 3
And summer as 5 ₂ is formed.

That is, when operating the first developing device 32 ₁ side,
As shown in FIG. 2, the magnetic roll 4 on the first developing device 32 ₁ side
3 ₁ while the magnetic pole portion 47 ₁ faces the developing position 36 _1, and the magnetic pole portions 45 ₁ and 46 ₁ doctor 3 substantially midway between the
₁ is positioned, and the magnetic roll 43 ₂ on the second developing device 32 ₂ side is arranged such that the magnetic pole portion 45 ₂ faces the doctor 37 ₂ . Then, the summer as developer magnetic brush 35 ₁ only to the developing roller 31 _first surface of the first developing device 32 ₁ side is formed.

When operating the second developing device 32 ₂ side,
As shown in the figure, the magnetic roll 43 ₁ on the first developing device 32 ₁ side
Is rotated about 25 degrees clockwise from the position shown in FIG. 2 so that the magnetic pole portion 45 ₁ faces the doctor 37 ₁ and the magnetic roll 43 ₂ on the side of the second developing device 32 ₂ is moved to the position shown in FIG. doctor 37 ₂ approximately midway between the magnetic pole portions 45 ₂ and 46 ₂ by approximately 25 degrees rotational displacement in the counterclockwise direction so as to position the. Then, the summer so that the second developing device 32 to only _two side developing roller 31 ₂ of the surface of the developer magnetic brush 35 ₂ is formed.

The magnetic pole portions 45 ₁ , 45 of the magnetic rolls 43 ₁ , 43 ₂
When facing ₂ to doctor ₃₇ 1, 37 ₂ made of a nonmagnetic material, the developing roller ₃₁ 1, 31 why the developer magnetic brush ₃₅ 1 on the surface of the _2, 35 ₂ is not formed, the magnetic pole unit ₄₅ 1, 45 ₂ where the weak force of adsorbing the developer G _1, G ₂ for the density of the magnetic brush is in a state of疏is because this order can be easily regulated by the doctor 37 _1, 37 _2,
Sleeve ₄₄ 1, the developer also 44 ₂ rotates _G 1, _{G 2}
Does not pass through the doctors 37 ₁ and 37 ₂ .

Incidentally, each of the drive portions of the first developing device 32 _1, or sleeve 44 ₁ of the developing roller 31 _1, developer stirring member ₄₀ 1,
Developer supply roller 52 ₁ is summer as driving force is transmitted through the first driving force transmission system 61 to be described later. Further, each of the drive portions of the second developing device 32 _2, that is, the development roller 31 _{and second} sleeve 44 _2, developer stirring member 40 _2, so that the driving force is transmitted through the second driving force transmission system 62 to be described later It has become. The first and second driving force transmission systems 61,
Reference numeral 62 is configured as shown in FIGS. 4 to 6, and the reversible motor 63 as a common drive source is rotated in the normal direction or the reverse direction, so that the first and second developing devices 3 are
And summer to operate 2 _1, 32 selectively only ₂ of one of the drive system.

Hereinafter, the driving force transmission system will be described in detail with reference to FIGS. 4 to 6. The first driving force transmission yarn 61 includes an intermediate gear 65 that meshes with the drive gear 64, a first driven gear 66 that meshes with the intermediate gear 65, an intermediate gear 67 that meshes with the driven gear 66, and an intermediate gear 67. Second mesh with
And a driven gear 68. Further, the second driving force transmission system 62 includes a third driven gear 69 that meshes with the driving gear 64.
And an intermediate gear 70 that meshes with the driven gear 69 and a fourth driven gear 71 that meshes with the intermediate gear 70. Then, when the drive gear 64 rotates in the forward direction, that is, in the direction of the solid arrow A in FIG. 4, each gear 65 to 68 of the first drive force transmission system 61 and each gear 6 of the second drive force transmission system 62.
When 9 to 71 rotate in the directions of solid arrows and the drive gear 64 rotates in the reverse direction, that is, in the direction of broken arrows B of FIG. 4, the gears 65 to 68 and the second drive force of the first drive force transmission system 61 are rotated. The gears 69 to 71 of the transmission system 62 are adapted to rotate in the directions of broken arrows.

Further, the first driven gear 66 to the drive shaft 72 ₁ of the integral ₁ and the first sleeve 44 of the developing roller 31 _1, the second driven gear 68
Are attached to the drive shaft 73 ₁ of the developer agitator 40 ₁ via the one-way clutches 74 and 74, respectively, and the drive shafts 72 ₁ and 73 ₁ rotate in the directions of solid line arrows 66 and 68, respectively. That is, the driving force is transmitted only when the driving gear 64 rotates normally, and the driving gear 64 rotates in the direction of the alternate long and short dash line. Further, the third driven gear 69 and the second developing roller 31 _{and second} sleeve 44 ₂ integral with the drive shaft 72
_2, the fourth driven gear 71 to the drive shaft 73 ₂ of the developer stirring member 40 ₂ is mounted via a one-way clutch 75, 75 respectively, each of the drive shaft ₇₂ 2, 73 ₂ gears 69, 71 is rotated in the direction of the broken line arrow, that is, the driving force is transmitted only when the drive gear 64 is rotated in the reverse direction, and is rotated in the direction of the alternate long and short dash line.

Further, the drive gear 64 has a bearing 7 as shown in FIG.
The rotary shaft 79 is rotatably supported via 6, and is mounted on a rotary shaft 79 that interlocks with a drive shaft 78 of the reversible motor 63 via a gear mechanism 77. That is, a gear 80 is attached to the rotary shaft 79, and the gear 80 is a motor mounting frame 81 and a stay 8 integrated with the motor mounting frame 81.
It meshes with a gear 85 rotatably attached to a support shaft 83 installed between the two and bearings 84, 84. A gear 86 having a larger diameter than that of the gear 85 is integrally formed with the gear 85, and the gear 86 is in mesh with a gear 87 attached to a drive shaft 78 of the reversible motor 63.
Thus, the rotations of the drive shaft 78 of the reversible motor 63 in both the forward and reverse directions are transmitted to the rotation shaft 79 via the gears 87, 86, 85 and 80, whereby the first and second developing devices 3 are
2 ₁ and 32 ₂ can be selectively operated only by the switching operation of the reversible motor 63 between normal rotation and reverse rotation.

Note that forward and switching of reversal of Ribashiburumota 63 is performed by pressing the color selection key on the operation panel to be described later, and by the magnetic roll drive means to be described later this time, magnetic roll 43 ₁ of those who do not work , 43 ₂ of the magnetic pole portions 45 ₁ and 45 ₂ can be switched so as to face the doctors 37 ₁ and 37 ₂ .

The intermediate gear 65 that meshes with the drive gear 64 and the first driven gear 66 is rotatably attached to the support shaft 89 via a bearing 88. The support shaft 89 is attached to an arm 91 that can swing around a housing 90 that holds bearings 76 and 76 that support the rotation shaft 79, and is securely connected to the drive gear 64 and the first driven gear 66. The position can be changed so that it can be meshed with.

Further, while stirring roller 53 ₁ of the first developing device 32 _1,
Together and summer to be intermittently driven through a first actuating mechanism 92 ₁ shown in FIG. 4, the other of the stirring roller 53 ₁ and the developer supply roller 52 ₁ in conjunction with the movement of the stirring roller 53 ₁ It is designed to be driven at the same time.
That is, the first developing unit 32 one of the stirring roller 53 ₁ of ₁
The axis 93 ₁ of the end which is attached Rachietsuto gear 94 _1, the Rachietsuto gear 94 ₁ solenoid 95
₁ is intermittently driven by a predetermined amount via a ratchet pawl 97 ₁ attached to a swinging arm 96 ₁ which is rotationally displaced in association with the on / off operation of ₁ . Further, the shafts 93 ₁ and 98 of the stirring rollers 53 ₁ and 53 ₁ and the shaft 99 ₁ of the developer replenishing roller 52 ₁ are fitted with sprockets (not shown), respectively, so that endless chains (not shown) are hung. The agitating rollers 53 ₁ and 53 ₁ and the developer replenishing roller 52 ₁ are integrally driven via this driving force transmission system (not shown).

Further, agitating roller 53 ₂ and the developer supply roller 52 of the _second developing unit 32 _2, the second actuating mechanism 92 ₂ and the driving force transmission system of substantially the same configuration of the first actuating mechanism 92 with _the same configuration as described above It is designed to be driven intermittently at the same time. The first actuating mechanism 92 ₁ of the same component parts will not be described in detail by reference numeral changing the Safuitsukusu character codes from _"1" to _"2".

Then, the developing roller ₃₁ 1 (31 ₂₎ surface developer magnetic brush ₃₅ 1 (35 ₂₎ or form, or magnetic roll ₄₃ 1 to remove (43 ₂₎ magnetic roll drive means for rotational displacement of The configuration of 100 ₁ (100 ₂ ) will be described with reference to FIGS. 7 to 9 (a) and (b). One end of the shaft 101 ₁ (101 ₂ ) of the magnetic roll 43 ₁ (43 ₂ ) is pivotally supported via a bearing 103 attached to the frame 102, and a lever 104 is attached to the tip thereof. The tip of the lever 104 is engaged with the engagement groove 1 of the arm 106 rotatably mounted via the support shaft 105.
It is in a state of being engaged with 07. Further, the support portion 108 formed at the lower part of the pivot end of the arm 106 is connected to the plunger 110 of the solenoid 109, and one end of the tension spring 112 is connected to the support portion 111 formed at the upper part of the pivot end. ing.

Thus, an alien state solenoid 109 is turned off, the arm 106 pulls the position indicated by the two-dot chain line in Figure 8 by the biasing force of the spring 112, i.e. the magnetic pole portion 45 ₁ as shown in FIG. 9 (a) (45 ₂ ) to the doctor 37 ₁ (37
_The lever 104 is held at a position opposed to ₂ ). Therefore, when the solenoid 109 is off, the developer magnetic brush 35 ₁ (35 ₂ ) is not formed on the surface of the developing roller 31 ₁ (31 ₂ ). Further, an alien state solenoid 109 is turned on, the arm 106 pulls the position indicated by the solid line in Figure 8 against the urging force of the spring 112, i.e. the magnetic pole portion 45 ₁ as shown in FIG. 9 (b) (45 ₂ ) to the doctor 37 ₁ (3
7 ₂ ), the lever 104 is rotationally displaced to a position facing it. Therefore, when the solenoid 109 is turned on, the developer magnetic brush 35 ₁ (35 ₂ ) is formed on the surface of the developing roller 31 ₁ (31 ₂ ).

Meanwhile, the doctor 37 ₂ described above is made of a nonmagnetic material as shown in FIGS. 2 and 3 doctor body 113
₂ , a magnetic body 114 made of a strip-shaped iron plate provided along the longitudinal direction of the doctor body 113 ₂ , and the doctor body 1
Magnetic 115 of steel plate provided 13 ₂ at both ends
₂ , 115 ₂ (only one is shown). Then, the magnetic 114,115 _2, 115 ₂
, When removing the developer G ₂ of the developing roller 31 and _second surface magnetic pole portion 45 ₂ is in opposition to the doctor 37 _2, the developer G ₂ to form a magnetic lines between the magnetic pole portion 45 ₂ It has a structure that can more reliably prevent ejection. Further, the doctor 37 ₁ has a doctor body 113 ₁ made of a non-magnetic material,
The doctor body 113 ₁ has magnetic materials 115 ₁ and 115 ₁ (only one of which is shown) made of an iron plate provided at both ends of the doctor body 113 ₁ , and the developer is the same as in the case of the doctor 37 _2. It is designed to prevent the removal of G ₁ . The doctor 37 _1, not Rarere magnetic body along the provided in the longitudinal direction of the doctor body 113 ₁ as described above of the doctor 37 _2, the developing roller 31 ₁ facing the doctor 37 ₁
And summer as by utilizing the magnetic field lines formed between the magnetic pole portions 45 ₁ and the developing roller 31 and _second magnetic pole portion 48 ₂ to prevent removal of the developer G _1.

Further, the magnetic flux density of between the developing roller 31 ₁ and the developing roller 31 _2, FIGS. 2 and 3 have magnetic plate 116 is provided as shown in FIG., The other magnetic roll ₄₃ 1 (43 ₂₎ The effect of the polar distribution is weakened, and good developer transport operation can be performed.

Incidentally, the 117 ₂ shown in FIGS. 2 and 3 with the developer remaining amount detecting device for detecting that the amount of the developer G ₂ of the second developing device 32 ₂ in Hotsupa 51 within ₂ has decreased below a predetermined value There, the permanent magnet 120 mounted on the sensing lever 118 integral with actuator 119 that rotationally displaced according to the amount of the developer is close to Ridosuitsuchi 121 as detector provided outside the Hotsupa 51 ₂ The configuration operates according to. Although not shown, the developer remaining amount detecting apparatus 117 ₁ of the developer remaining amount detecting device 117 ₂ and the same configuration is provided also to Hotsupa 51 ₁ of the first developing device 32 _1.

Further, as shown in FIGS. 2, 3, and 10, a hopper cover 131 forming a part of the upper surface of the main body 1 is provided on the upper surface side of the developing device 10 so as to be openable and closable, and the hopper cover 131 is opened. When the lid member 133 ₂ for opening and closing the lid 133 ₁ and the second developing unit 32 ₂ of the developer upper opening 132 _{and second} replenishment opening and closing the upper opening 132 of the _first developing device 32 ₁ developer for replenishment It is exposed. Then, by opening the lids 133 ₁ and 133 ₂ ,
Replenishment of the developers G ₁ and G ₂ can be easily performed from the upper surface side. Note that the above-mentioned lid ₁₃₃ 1, 133 ₂ have the color display unit ₁₃₄ 1, 134 ₂ are provided,
The colors of the developers G ₁ and G ₂ housed inside are easily discriminated, and the developers of different colors are prevented from being mistakenly mixed in.

Reference numeral 135 shown in FIGS. 2 and 3 denotes a cover open / close detection device for detecting the open / close state of the hopper cover 131, and the permanent magnet 13 attached to the tip of the hopper cover 131.
6 and a lead switch 137 as a detector that is turned on when the magnet 136 approaches when the hopper cover 131 provided on the main body 1 side is closed.

Further, as shown in FIGS. 10 and FIG. 11 (a) (b), first, second developing device ₃₂ 1, 32 ₂ of Hotsupa ₅₁ 1,
51 ₂ of the top surface ₁₃₈ 1, 138 _2, the cover ₁₃₃ 1, 1
_On both sides of 332, integrated time meters 139 ₁ , 139 ₂ as life indicators for displaying the developer life,
And Hotsupa ₅₁ 1, 51 developer without indicator developer in ₂ to display that has decreased below a predetermined amount ₁₄₀ 1, 14
0 ₂ is provided. The total time 139 ₁ , 13
9 _2, for example by measuring the developing roller ₃₁ 1, 31 sleeve _{44 1 2} constituting, 44 ₂ of the rotation amount (time), respectively, which display the life of the developer, respectively, for example, (Corporation) It uses an electrolytic integration time meter (brand name FC timer) manufactured by Fuji Ceramics.

On the other hand, the first developing device color developer _{G 1} is housed 32 ₁
Is a detachable cartridge type with respect to the main body 1 and can be easily removed by pulling up the handle 141 (see FIG. 10) in an upright state. In other words, the first developing device 32 ₁ developer supply unit 34 ₁
Positioning members 142, 142 (only one of which is shown) are attached to both front and rear wall portions of the positioning member 14
Both end support portions 144 and 144 of the handle 141 are rotatably and pivotally attached to 2, 142 via support shafts 143, 143. As shown in FIGS. 12 and 13 (a), (b), and (c), a hook 145 that is rotatable around a support shaft 143 is provided on the support portions 144 and 144 of the handle 141, respectively.
Are integrally attached, and are configured so that they can be engaged with a locking pin 146 provided on the main body 1 side to restrict upward movement. Further, the engaging groove 147 as the first positioning portion and the end surface 148 as the second positioning portion formed in the lower end portion of the positioning member 142 are engaged with the positioning pins 149, 150 provided on the main body 1 side. The first developing device 32 ₁ is held in contact with the first developing device 32 ₁ at a predetermined position. Then, when the handle 141 is erected, as shown in FIG.
The engaging pin 146 is disengaged, and when the handle 141 is tilted to a substantially horizontal state, the hook 145 is engaged with the engaging pin 146 as shown in FIG. By pushing in, as shown in FIG. 13 (c), the hook 145 and the locking pin 146 are released from the first developing device 3.
It is ensured that the 2 ₁ is engaged in a state of being pressed downward. Therefore, if the handle 141 is in an upright state, the first developing device 32 ₁ can be attached and detached, and if the handle 141 is tilted after the first developing device 32 ₁ is inserted, the first developing device 32 ₁ can be pulled down.
₁ can be fixed, and the operation becomes extremely easy.

Next, the developing operation of the developing device 10 will be described. First, when the first developing device 32 ₁ side is selected to operate by the color selection key, the magnetic rolls 43 ₁ and 43 ₂ enter the state shown in FIG. 2 and the reversible motor 63 rotates in the normal direction to The sleeve 44 ₁ of the developing roller 31 ₁ rotates clockwise in the state shown in FIG. 2 to form the developer magnetic brush 35 ₁ on the surface of the sleeve 44 ₁ . Then, the electrostatic latent image previously formed on the photosensitive drum 7 is developed with the color developer G ₁ . In this way
When the development of the electrostatic latent image is completed, the magnetic roll 43 ₁
Is rotated about 25 degrees to move the magnetic pole portion 45 ₁ to the doctor 37 ₁
By opposing the, new formation of the developer magnetic brush 35 ₁ to the sleeve 44 ₁ above is stopped, the developer magnetic brush 3 further sleeve 44 ₁ in this state is rotated by a predetermined amount
5 ₁ is removed. At this time, the second developing roller 31
₂ to be not formed with the developer magnetic brush 35 _2, then any of the developing units 32 _1, 32 ₂ a defect such as even color mixing is selected is summer so as not to cause.

When the second developing device 32 ₂ is selected for black development, the magnetic rolls 43 ₁ and 43 ₂ are brought into the state shown in FIG. 3 and the reversible motor 63 is rotated in the reverse direction so that the second developing roller 31 ₂ of the sleeve 44 ₂ is rotated in the clockwise direction in the state of FIG. 3, to form a developer magnetic brush 35 ₂ on the surface of the sleeve 44 _2. Then, will end the developing operation while an electrostatic latent image on the photosensitive drum 7 in the same manner as described above after the black developing, removing the developer magnetic brush 35 ₂ from the surface of the sleeve 44 _2.

Incidentally, in the developing operation state the developing unit ₃₂ 1 (32 ₂₎ of the developer stirring member ₄₀ 1 (40 ₂₎ and the stirring roller 53 ₁
(53 ₂ ) is always operating, and the developer replenishing roller 52 ₁ (52 ₂ ) is the developer concentration detector 42 ₁ (42
₂ ) The developer G _{1 is} appropriately controlled by the control signal based on the output signal of
The (G ₂ ) replenishing operation is performed, and the good developing operation is maintained.

FIG. 14 shows the operation panel, which includes a copy key 151 for executing a copy operation, an interrupt key 152 for specifying an interrupt mode in which interrupt copying is performed, and an interrupt mode indicating that it is in interrupt mode. Built-in display 153, numeric keypad 154 for setting the number of copies, number display section 155 for displaying the number of copies, color selection key 156 for selecting a color for copying (eg, black, red, blue, green), selected color A color display unit 157 to 160 for displaying, a liquid crystal display unit 161 for displaying an operating state, a density setting unit 162 for setting a copy density, and the like are provided. In the liquid crystal display section 161, 163 is a copyable display symbol indicating that the copying operation is possible, 164 is a copy prohibition display symbol indicating that the copying operation is impossible, and 165 is the developing device 10. This is a symbol indicating no developer, which indicates that the developer is exhausted in the hopper. It should be noted that the color selection key 156 can be used to select colors alternately each time the color selection key 156 is pressed. That is, if the first developing device 32 ₁ is red and the second developing device 32 ₂ is black, for example, when the power is turned on, the black copying mode is automatically set, and the second developing device 32 ₂ is selected to display the color. The container 157 lights up. The color selection key 156 is depressed in this state, the first developing device 32 ₁ is selected Te summer and red copy mode, the color indicator 158 is illuminated. When the color selection key 156 is pressed again in this state, the black copy mode is resumed. Thus, each time the color selection key 156 is pressed, the black copy mode and the red copy mode can be selected alternately.

FIG. 15 shows the entire control circuit. That is, reference numeral 171 denotes a microcomputer (hereinafter simply referred to as a microcomputer) as a main control unit, which controls the entire copying machine. The inputs of the microcomputer 171 are input switches 173 such as various keys on the operation panel via the input interface circuit 172, various other switches necessary for copying operation, sensors 174, and the first developing machine 32.
_{No. 1} developer concentration detector 42 ₁ and developer remaining amount detector 117 ₁ ; developer concentration detector 4 of the second developer 32 _2.
2 ₂ and the developer remaining amount detecting device 117 _2, such as the cover closing detection device 135 is connected. Also, microcomputer 1
A storage device 175 is connected to 71, and the storage device 175 is backed up by a back-up power source 176 such as a battery. On the other hand, the output of the microcomputer 171 is output via the output interface circuit 177 to the display device 17 such as various display devices and display units of the operation panel.
8, the pole position switching solenoids 109 and 109 of the first developing device 32 ₁ and the second developing device 32 ₂ , the reversible motor 63, and the integrated time meter 139 of the first developing device 32 _1.
1, the second developing unit 32 ₂ of the integrated time meter 139 _2, the developing bias power supply 179, the charging power source 180 of the main charger 8, transfer power supply 181 of the transfer charger 11, the peel charger 12 peeling power source 182, the static elimination lamp 14, the developer-less indicators 140 ₁ and 140 ₂ , the main motor 28, and other various solenoids 18
3, a document table driving device 184 for driving the document table 2, an exposure lamp control circuit 185, etc. are connected. The exposure lamp control circuit 185 controls the exposure lamp 22 according to the output signal of the automatic exposure sensor 186 which detects the light from the exposure lamp 22 and the signal from the microcomputer 171.

The first developing device 32 ₁ and the second developing device 32 ₂ each have a developing device presence / absence signal generating means 18 indicating the presence / absence of a developing device.
7 ₁ 187 ₂ and identification information generating means 188 ₁ 188 ₂ for generating an identification code unique to the developing device (which also represents the color of the developer contained) are provided, and signals and identification codes from these are also input. It is input to the microcomputer 171 via the interface circuit 172. The developing device presence signal generation means ₁₈₇ 1, 187 ₂ and the identification information generating unit ₁₈₈ 1, 188 _2, for example, as shown in FIG. 16, a developing device connector for electrically connecting to the developing unit control circuit It is adapted to generate a signal and an identification code respectively. That is, 191 is the connector, which is composed of a jack 192 and a plug 193, the jack 192 is provided on the developing device side, and the plug 193 is connected to the control circuit of FIG. 15 via a cable. At Jiyatsuku 192, the terminal 194 ₁ as a common, so as to generate a developing device presence signal by coupling the terminal 194 ₁ and the terminal 194 _5, also the terminal 194 ₁ and the terminal ₁₉₄ 2-194 ₄ A 3-bit identification code is generated by connecting according to the developing device. On the other hand, in the plug 193, the terminal 19
5 ₁ is grounded on the control circuit side and the terminal 19
5 _{2-195 5} is connected to the input Intafueisu circuit 172. Thus, when the Jiyatsuku 192 and plug 193 are connected, in which each terminal is compatible connected, three bits in accordance with the connection state of the terminal in Jiyatsuku 192 thereby from the terminal ₁₉₅ 2-195 ₄ plugs 193 identification code is obtained, and summer as the developing unit present signal is obtained from the terminal 195 _5. Therefore, Jack 1
If 92 and the plug 193 is not connected, the terminal 195 ₅ of the plug 193 not developing unit present signal is obtained, it can be determined that no developing device (developing unit is not mounted).

The storage device 175 is, for example, a CMOS RA.
M (random access memory) is used as a counter for counting the number of copies (the number of copying operations). The details will be described below. That is, in this embodiment, for example, a plurality of sheet number counters for each developing device for counting the number of sheets for each developing device and one total sheet number counter for counting the total number of sheets are provided. It is selected by addressing according to the identification code of the container, and the count data is stored in each. The count data of each of the above-mentioned sheet number counters is composed of, for example, 4 bits × 5, and is stored as a BCD code. Also, the count data of the total number of sheets is composed of, for example, 4 bits × 6, and is stored in the BCD code.

Next, the operation of the above configuration will be described. First, the operation when the power is turned on will be described using the flow chart shown in FIG. When the power is turned on, the process proceeds to step A1. In step A1, select the automatic exposure mode with selecting a second developing device 32 ₂ black developer as a reference color is accommodated, the process proceeds to step A2. In step A2, the heater lamp of the heat roller 19 is turned on, and the process proceeds to step A3. In step A3, it reversed the Ribashiburumota 63 turns off the second developing unit 32 ₂ of the pole-position switching solenoid 109, the process proceeds to step A4. At step A4, the reversible motor 63 is stopped, and the process proceeds to step A5. In step A5, the pole position switching solenoid 109 of the first developing device 32 ₁ is turned off, the reversible motor 63 is normally rotated, and the process proceeds to step A6. At step A6, the reversible motor 63 is stopped, and the process proceeds to step A7. In step A7, the main motor 28 is turned on for a certain period of time, and the process proceeds to step A8. At step A8, it is checked whether or not the warm-up of the heat roller 19 is completed, and when it is completed, the copyable display symbol 163 on the operation panel is turned on to enter the standby state, and at step A9, the key on the operation panel is pressed. Accept the operation. Next, the process proceeds to step A10 and the interrupt key 1
It is checked whether 52 is turned on or not. If it is not turned on, the process proceeds to step A11, and if it is turned on, the process proceeds to step A12. At step A12, it is checked whether or not the interrupt mode is currently set. If not, the process proceeds to step A13. In step A13, interrupt key 15
2 is copying conditions just before it is turned on, i.e. copy density, as well as saving the color and copy setting the number of copy, and select the second developer 32 ₂ and磁露light mode the black developer is accommodated, further copy setting The number of sheets is set to "1", the interrupt mode is set, and the process proceeds to step A14. in this way,
When the interrupt mode is set, the copy condition immediately before that is saved and the mode is switched to the black copy mode as the reference color. Next, in step A14, the interrupt indicator 153 on the operation panel is turned on, and the process proceeds to step A11. On the other hand, if the interrupt mode is set at step A12, the process proceeds to step A15. At step A15,
The copying conditions saved in step A13 are restored, the selection of the developing device and the exposure mode is returned to the selection state immediately before the start of the interrupt mode, the interrupt mode is canceled, and the process proceeds to step A16. At step A16, the interrupt indicator 153 on the operation panel is turned off, and the process proceeds to step A11.

In step A11, whether by a developing device presence signal from the second developing device 32 ₂ second developing device 32 ₂ is mounted to a checking, the process proceeds to step A17 if not mounted. In step A17, the developing device presence signal from the first developing device 32 ₁ first developing device 32 ₁ is a checking whether it is attached, if not mounted step A
Proceed to 18. In step A18, the color indicators 157 to 160 and the copyable display symbol 163 on the operation panel are displayed.
Go out and return to the standby state. Thus, if the first developing device 32 ₁ and the second developing device 32 ₂ is not completely attached, in which it allowed to prohibit the display color by the color indicator 157-160. On the other hand, in step A11, the second developing unit 32 ₂ advances to step A19 if it is mounted. In step A19, it is checked whether or not the first developing device 32 ₁ is attached, and if it is attached, the process proceeds to step A20. In step A20, it is checked whether or not the color selection key 156 is turned on, and if it is turned on, the process proceeds to step A21. In step A21, whether the second developing unit 32 ₂ is currently selected by a checking, if it is not selected step A2
Go to 2. In step A22, select the second developing unit 32 _2, the process proceeds to step A23. In the step A19, the first developing device 32 ₁ is not mounted, the process proceeds to step A22 and jumps to step A20, A21. In step A20, the color selection key 1
If 56 is not turned on, steps A21 and A22
And jump to step A23. On the other hand, if the first developing device 32 ₁ is attached in step A17, or if the second developing device 32 ₂ is selected in step A21, the process proceeds to step A24.
In step A24, the first developing device 32 ₁ is selected, and the process proceeds to step A23. As described above, when the first developing device 32 ₁ and the second developing device 32 ₂ or one of them is not mounted, the selection of the developing device is prohibited. At step A23, the color of the selected developing device is displayed. That is, the color of the developer contained in the selected developing device is discriminated based on the identification code output from the developing device, and the color display on the operation panel corresponding to the color is turned on. For example, if the discrimination color is black, the color indicator 15
7 is turned on, and if it is red, the display 158 is turned on.

When the color display is performed in this way, the process proceeds to step A25. In step A25, the remaining developer amount detecting devices 117 ₁ , 117
The signal from the _2, first, second developing device ₃₂ 1, 32 ₂
It is checked which of the developing devices does not have the developer, and if neither has the developer, the process proceeds to step A26. In step A26, the first and second developing devices 32 ₁ , 3
2 No ₂ of the developer indicator ₁₄₀ 1, 140 ₂ turns off, and the flow proceeds to step A27. On the other hand, the above step A25
In step S28, if either of the developing devices has no developer, the process proceeds to step A28. In step A28, the signal from the cover open / close detection device 135 is used to check whether the hopper cover 131 of the developing device 10 is closed. If it is closed, the process proceeds to step A26, and if it is not closed, the process proceeds to step A29. In step A29, the corresponding developing unit (developing device without the developer) of the developer without display 140 ₁
Or 140 ₂ lit, the process proceeds to step A27. As described above, the hopper 51 of the first and second developing devices 32 ₁ and 32 _2
1, 51 developer _G 1 in the _2, if _{G 2} has come not is intended to light up the upper opening ₁₃₂ 1, 132 without the developer provided in the vicinity of the _second display unit ₁₄₀ 1, 140 ₂ . At this time, the developer-free indicators 140 ₁ and 140 ₂ are not turned on if the hopper cover 131 is closed, and are turned on only when they are opened. Step A2
In step 7, it is checked whether the developing device selected at this time has no developer. If not, step A3 is selected.
Go to 0. In step A30, the developer-less display symbol 165 on the operation panel is turned off, and the process proceeds to step A31. On the other hand, in step A27, if the selected developing device does not contain the developer, the process proceeds to step A32. In step A32, the developer-less display symbol 165 on the operation panel is turned on, and the process proceeds to step A31. In this way, only when the selected developing device runs out of developer, it is displayed on the operation panel.

In step A31, it is checked whether or not there is an abnormality in the copying machine. If there is an abnormality, the abnormality processing is performed, and if there is no abnormality, the process proceeds to step A33. In step A33,
Check whether the manual paper feed mode using the manual paper feed table 6 is set. If the manual paper feed mode is not selected, step A
Proceed to 34. In step A34, and a checking whether or not there is a sheet P ₁ in the paper feed cassette 3, returns to the standby state if no, the process proceeds to step A35 if. On the other hand, in step A33, if the manual feed mode is selected, step A34 is jumped to proceed to step A35.
In step A35, the first and second developing devices 32 ₁ , 32 ₂
The developing device presence / absence signal from is checked to see if the developing device has been attached / detached. If the developing device has been attached / detached, the process proceeds to step A36. At step A36, a signal from the cover open / close detection device 135 is used to check whether or not the developing device is securely attached. In this case, if the cover open / close detection device 135 detects that the hopper cover 131 is closed, it is determined that the cover cover 131 has been installed. When it is determined that the developing device is attached, the process proceeds to step A37. In step A37, the developer on the sleeve of the detached developing device is removed by performing the above-described operation, and the operation returns to the standby state. In this way, when the developing device is attached / detached while the power is turned on, after the developing device is securely attached, the developer on the sleeve 6 of the attached / detached developing device is operated to be removed. It is what makes me. On the other hand, in step A35, if the developing device is not attached / detached, the process proceeds to step A38. Step A3
In step 8, whether or not the copy key 151 on the operation panel is turned on is checked. If it is turned on, the copying operation described later is performed, and if not turned on, the processing proceeds to step A39.
In step A39, it is checked whether or not a key operation has been performed on the operation panel for a certain period of time. If an operation is performed, the operation returns to the standby state, and if no operation is performed, the operation proceeds to step A40. In step A40,
It is checked whether or not the interrupt mode is currently set. If it is not the interrupt mode, the process proceeds to step A41. In step A41, the copy setting number with selecting the second developing unit 32 ₂ and an automatic exposure mode black developer is accommodated "1"
To return to the standby state. In this way, when no operation is performed for a certain period of time after the normal copying operation is completed, the black copying mode as the reference color and the automatic exposure mode are switched. On the other hand, if the interrupt mode is set in step A40, the process proceeds to step A42. At step A42, the copy condition saved at the time of setting the interrupt mode is restored, the interrupt indicator 153 on the operation panel is turned off, and the operation returns to the standby state. in this way,
If the operation is not performed for a certain period of time after the interrupt copying in the interrupt mode is performed, the state immediately before the start of the interrupt mode is restored.

Next, the copying operation will be described using the flow chart shown in FIG. When the copy key 151 on the operation panel is turned on, the process proceeds to step B1. At step B1,
The pole position switching solenoid 109 of the selected developing device is turned on, and the process proceeds to step B2. In step B2, the reversible motor 63 is rotated in the direction of the selected developing device, and the process proceeds to step B3. In step B3, the blade solenoid 29 of the cleaning device 13, the static elimination lamp 14, the main motor 28, the transfer power source 181 (transfer charger 11), the peeling power source 182 (peeling charger 12), and the developing bias power source 179, respectively. Turn on and proceed to step B4. In step B, the paper feeding operation from the paper feeding cassette 3 is started, and the process proceeds to step B5. In step B5, the document table 2
Is checked to see if it is in the fixed position. If it is not in the fixed position, the process proceeds to step B6 to return to the fixed position, and when the document table 2 returns to the fixed position, the process proceeds to step B. In step B7, the exposure lamp 22 is turned on, and the process proceeds to step B8. Step B8
Then, the charging power source 180 (charging charger 8) is turned on to start charging the photoconductor drum 7, and the document table 2 is moved forward to start scanning the document, and the process proceeds to step B9.
In step B9, the resist roller 18 by rotary feed the sheet _{P 1} to the image transfer unit 16, the process proceeds to step B10.
In step B10, the number display section 155 on the operation panel is displayed.
The display content of "1" is subtracted, and the storage device 175
The total number of sheets and the number of sheets of the selected developing device are incremented by "1", and the process proceeds to step B11. In step B11, the charging power source 180 is turned off to stop the charging of the photosensitive drum 7, and the process proceeds to step B12. In step B12, the exposure lamp 22 is turned off, and the process proceeds to step B13. In step B13, the document table 2 is moved backward and the process proceeds to step B14. In step B14, it is checked whether or not the document table 2 has returned to the fixed position, and when it returns to the fixed position, the process proceeds to step B15. At step B15, the rotation of the registration roller 18 is stopped, the backward movement of the document table 2 is stopped, and the process proceeds to step B16. In step B16, it is checked whether or not the set number of copies have been completed, and if completed, the process proceeds to step B17. In step B17, the signal from the developer concentration detector of the selected developing device is used to check whether the developer concentration of the selected developing device is equal to or higher than the lower limit concentration level. If the lower limit density level is not reached, the process proceeds to step B19. Step B19
Then, it is checked whether or not the developer has been replenished for a certain period of time. If not, the process returns to step B17 to repeat the above operation, and if the developer is replenished for a certain period of time, the process proceeds to step B18. That is, in the automatic developer density control, it has an appropriate density level and a lower limit density level for not changing the flow characteristics of the developer, and at the end of the copying operation, the developing device is kept until the developer density reaches the lower limit density level. Drive to continue supplying the developer. Step B18
Then, the pole position switching solenoid 109 is turned off, and the process proceeds to step B20. In step B20, the reversible motor 63 is stopped, and the process proceeds to step B21. Step B21
Then, the blade solenoid 29, the main motor 28, the charge eliminating lamp 14, the transfer power source 181, the peeling power source 182, and the developing bias power source 179 are turned off, and the system returns to the standby state.

On the other hand, in step B16, if copying of the set number of sheets has not been completed, the process proceeds to step B22. Step B
In step 22, the life of the developer is checked by checking whether the value of the number-of-sheets counter for each developing device in the storage device 175 has reached a preset predetermined value, and if the life is not reached, step B23. Proceed to. In step B23, the color change request flag described later is "1".
By checking whether or not there is a color change request, it is checked whether or not there is a color change request.
0) Return to step B4 and repeat the above-mentioned operation,
If there is a color change request (flag = 1), the process proceeds to step B24. In step B24, the selection of the developing device is changed, and the process proceeds to step B25. In step B25, the pole position switching solenoid of the previously selected developing device is turned off, and step B25
Proceed to 26. In step B26, the reversible motor 6
3 is stopped, the operation is returned to the step B1, and the above-mentioned operation is repeated. In this way, when a request to change the selection of the developing device is issued during the copying operation, the developing device to be used is switched at least after the development of the image in the middle of copying is completed. On the other hand, if the life of the developer is reached in step B22, the process proceeds to step B27. At step B27,
If there is another developing device of the same color, check whether or not there is another developing device of the same color, and if not, return to the step B4 and repeat the previously described operation, and if there is another developing device of the same color, proceed to step B28. In step B28, the developing device of the same color is selected, and the process proceeds to step B25. In this way, when the developer in the developing device in use has reached the end of its life, if there is another developing device, that is, a developing device accommodating the developer of the same color, it is preferentially switched to that developing device.

Next, the interrupt processing will be described using the flow chart shown in FIG. This interrupt process is set to be repeated at regular intervals. When the interrupt process is started, the process proceeds to step C1. At step C1, it is checked whether the reversible motor 63 is rotating (the developing device is operating), and if it is rotating, the process proceeds to step C2. In step C2, the integrated time meter 139 ₁ or 139 ₂ of the selected developing device is energized, and the process proceeds to step C3. At step C3, it is checked whether or not the A flag is "1", and if not, it proceeds to step C4. At step C4, the timer A starts counting,
Proceed to step C5. In step C5, the above timer A is used.
Is checked for 5 seconds, and if 5 seconds have been counted, step C6 follows. In step C6, "1" is set in the A flag, and the process proceeds to step C7. If 5 seconds have not been counted in step C5, step C6
And jump to step C7. On the other hand, in step C3, if the A flag is "1", the process proceeds to step C8. In step C8, the signal from the developer density detector 42 ₁ or 42 ₂ of the selected developing unit, and a checking or lower or not than a predetermined value the developing agent concentration of a selected developing unit is set in advance If it is low, the process proceeds to step C9. In step C9, performs developer replenishing operation by driving the developer supply roller 52 ₁ or 52 ₂ of the selected developing device, the process proceeds to step C7. If it is higher than the predetermined value in step C8, step C9 is jumped to proceed to step C7. In this way, after the copying operation is started, the developer concentration detector 4 is started after the supply of the developer onto the magnetic rolls 43 ₁ and 43 ₂ is started.
After a predetermined time when the flow of the developer to 2 ₁ , 42 ₂ becomes stable (for example, from about 5 seconds, the developer concentration detectors 42 ₁ , 42 2
_The density check is performed by the output of ₂ . In step C7, it is checked whether or not the color selection key 156 on the operation panel is turned on, and if it is turned on, the process proceeds to step C10. In step C10, the color change request flag is set to "1", and the process proceeds to step C11. If the color selection key 16 is not turned on at the step C7, the step C10 is jumped to proceed to the step C11.

On the other hand, in the step C1, the reversible motor 6
If 3 is not rotating, proceed to step C12. In step C12, "0" is set in the A flag, the timer A is reset, the energization of the integrated time meter 139 ₁ or 139 ₂ is turned off, and the process proceeds to step C11.
In step C11, it is checked whether or not there is a display request for the total number of copies (encrypted by the ten keys 154 on the operation panel). If there is a display request, step C11 is executed.
Proceed to 13. In step C13, the contents of the total number counter in the storage device 175 are displayed on the number display section 1 on the operation panel.
Display at 55 and proceed to step C14. Step C above
In step 11, if there is no request to display the total number of copies, the process proceeds to step C. In step C15, the first developing device 32 ₁
Check whether or not there is a display request for the number of copies made by the (key code input with the ten key 154).
If there is a display request, the process proceeds to step C16. Step C1
In 6, the contents of the number counter corresponding to the first developing device 32 ₁ in the storage device 175 are displayed on the number display section 155, and the process proceeds to step C14. If there is no display request in step C15, the process proceeds to step C17. Step C1
In 7, and a checking whether or not there is (are input in the encryption by the ten key 154) the second developing unit 32 ₂ by the display request number of copies has been copied, step C If there is a display request
Proceed to 18. In step C18, to display the contents of the number counter corresponding to the second developing device 32 ₂ in the storage device 175 in the number display section 155, the process proceeds to step C14. If there is no display request in step C17, step C
Proceed to 19. At step C19, the normal number of copies is displayed on the number display section 155, and the procedure goes to step C. At step C14, it is checked whether or not there is a request for clearing the number of copies for each developing device (entered by the ten-key 154 with a code for each developing device). If there is no clear request, the interrupt processing is ended here. If there is a clear request, the process proceeds to step C20. In step C20, the contents of the number counter corresponding to the designated developing device in the storage device 175 are cleared, and the interrupt process is ended.

With the configuration as described above, since the total number of sheets counter for counting the total number of copied sheets and the number of sheets for counting the number of copied sheets for each developing device are provided, the developer life can be accurately and easily provided for each developing device. I can judge.

In the above embodiment, the number of copies for each developing device is counted by the number counter, but the number of copies for each color of the developer may be counted. By doing so, the life of the developer can be accurately and easily determined for each color of the developer.

Further, in the above-described embodiment, the case where the present invention is applied to a monochromatic color copying machine is explained, but the present invention is not limited to this, and for example, a so-called multi-color copying machine for copying a large number of colors or a facsimile machine. For example, any image forming apparatus that forms an image using a developing device can be applied.

[Effect of the Invention] As described in detail above, according to the present invention, it is possible to provide an image forming apparatus capable of accurately and easily determining the developer life for each developing unit or for each color of a developer.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention. FIG. 1 is a schematic configuration diagram of a color copying machine, FIG. 2 is a schematic vertical sectional side view of a developing device, and FIG. 3 shows different operating states of the developing device. FIG. 4 to FIG. 6 are schematic vertical side views showing the structure of a driving force transmission system. FIG. 4 is a front view showing a meshing state of gear groups, and FIG. 5 is a sectional view shown in an expanded state. 6 and 6 are sectional views showing a driving force transmission state to a drive gear, FIG. 7 is a plan view showing a partial cross section of the magnetic roll driving means, and FIG. 8 is a side view of the magnetic roll driving means. 9 is an explanatory view showing the operating state of the magnetic roll driving means, FIG. 10 is a schematic perspective view of the developing device section, FIG. 11 is a plan view showing the upper surface of each developing device, and FIG. 12 is a fixing of the developing device. FIG. 13 is a plan view showing the structure, FIG. 13 is an explanatory view showing the engagement / disengagement relationship between the handle and the hook, and FIG. 14 is a plan view of the operation panel. Fig. 5 block diagram showing an overall control circuit schematically explanatory diagram for FIG. 16 illustrating the developing device presence signal generating means and the identification information generating means, first
7 is a flow chart for explaining the operation when the power is turned on, FIG. 18 is a flow chart for explaining the copying operation, and FIG. 19 is a flow chart for explaining the interrupt processing operation. P ₁ , P ₂ ... Paper, 1 ... Copy machine main body, 2 ... Manuscript table, 7 ...
Photosensitive drum, 10 ... developing device, ₃₂ 1, 32 2 _... developing device, 156 ... color selection key, 157-160 ... color indicator,
171 ... Microcomputer, 175 ... Storage device (CMOS RA
M), 176 ... Backup power supply, 188 ₁ , 188 ₂
... Identification information generating means.

Claims (1)

[Claims] 1. A first developing means for forming an image on an image carrier with a first developer, and an image on the image carrier with a second developer different from the first developer. Second developing means for forming, supporting means for supporting the first developing means and the second developing means, and the first developing means and the second developing supported by the supporting means. When the selecting means for selecting either one of the means and the developing means selected by the selecting means are the first developing means, the first number of times the first developing means has performed the developing operation is set. When the first counting means for counting and the developing means selected by the selecting means are the second developing means, a second number of times the second developing means executes the developing operation is counted. And a third counting means for summing the first number and the second number. Third counting means for counting the number of times, designation means for designating any one of the first number of times, the second number of times, and the third number of times, and the number of times designated by the designating means An image forming apparatus comprising: a display unit for displaying