JPH10268621A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To correctly detect a developer-empty state regardlessly of the developer capacity of each strong part and to reduce the number of components, by detecting the amount of developer that each developer carrying means has carried, and outputting a developer-empty-state signal when the total of the amounts that the developer has been carried reaches a value equal to or higher than a preset value. SOLUTION: The carrying screw 431Y, etc., are rotated by driving and rotating a carrying-screw gear 432Y, etc., so that the developers in the corresponding developer-storing means are added to corresponding developing units. The numbers of rotations of the carrying screw 431Y, etc., which coincide the exhaustion of the developers in the corresponding developer-storing means are set in advance, and the rotations of the carrying screws 431Y, etc., which are actually operated are counted. This prevents variations between machines and makes it possible to detect accurately amounts of remaining developers. The particular count-numbers of the carrying screws 431Y, etc., which are set for corresponding colors can be determined based on amounts of developers carried each time the carrying screws 432Y, etc., each make one rotation and amounts of developers stored in corresponding cartridges.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus provided with a developer replenishing device for supplying a developer from a developer storing section for storing the developer to the developing device.

[0002]

2. Description of the Related Art Conventionally known image forming apparatuses include:
The electrostatic latent image formed on the image carrier is visualized by a developer contained in a developing unit, and is transferred to a predetermined sheet and fixed to form an image.

[0003] Therefore, the developer is consumed for the image formation, and new developer must be supplied to the developing means. Therefore, a developer replenishing device is provided which is provided with a developer storing part for storing the developer and replenishes the developing means with the developer from the developer storing part.

[0004]

The developer replenishing apparatus and the image forming apparatus equipped with the above-mentioned developer cartridge have the following problems.

In order for the image forming apparatus to always form a good image with a constant image density, the remaining amount of the developer stored in the developer storage section is detected, and when the remaining amount of the developer is small. Must inform the user to supply developer to the developer reservoir.

There have been many means for detecting the remaining amount of the developer in the developer storage unit. For example, in some cases, a detection unit for detecting the remaining amount of the developer in the developer storage unit using an electric unit such as an optical sensor or a piezoelectric element is provided. However, when the detecting means is provided in the developer storage section, the apparatus becomes complicated due to wiring and the like.

Particularly, in a downsized developer replenishing apparatus having a small developer storage section, a developer cartridge to be replaced is prepared in order to detect the remaining amount of developer only when the remaining amount of developer becomes small. If not, the residual developer in the developer storage may be exhausted and image formation may not be possible.

In a color image forming apparatus, a plurality of developer storages corresponding to the developers of the respective colors are usually installed. Therefore, the above-described detection is performed in each developer storage. The installation of the means increases the number of parts, complicates wiring, and increases the manufacturing cost.

Further, there are detection means described in JP-A-62-291680 and JP-A-62-222279. This detection means counts the number of transmissions of the control signal, and detects that the toner storage unit is in an empty state when a predetermined number of empty times is reached.

In this technique, the detection is performed on the premise that the screw rotation time on the control and the actual screw rotation time match, but it does not actually match. That is, since the influence of the torque of the screw and the like varies from machine to machine, the rise and fall times of the screw rotation operation differ depending on the machine, and the control rotation time and the actual rotation time necessarily differ.

As a result, there is a possibility that the toner may actually be erroneously detected as not present in the toner container, and it is difficult to accurately detect the remaining amount of toner by counting the control signal.

FIG. 10 is a characteristic diagram showing the correlation between the timing of the developer supply signal and the rotation speed (rpm) of the transport screw. As shown in the drawing, the rotation of the transport screw starts (rises) with a delay after the developer supply signal is turned on, and decelerates and stops (falls) with a delay after the developer supply signal is turned off. . Moreover, the rotation speed of the transport screw is not constant. The rise and fall of the rotation of the transport screw and the fluctuation of the rotation speed change depending on the torque of the transport screw and the like, and the individual difference of the apparatus is large.

FIG. 11 is a characteristic diagram showing the relationship between the supply signal time and the transport screw rotation time. In the figure, the horizontal axis represents the measured model of the developer supply device, the measured machine number, the number of measurements,
(Y1, y2, y3), (m1, m2), (c1, c
2) and (k1, k2), and the vertical axis indicates the rotation time of the transport screw. The supply signal was set to 300 ms, and the rotation time of the transport screw at that time was measured. As shown here, the transport screw rotation time varies from measurement to measurement and from device to device.

That is, if the replenishment amount of the developer is converted based only on the number of transmissions of the replenishment signal, an extremely large error occurs.

As described above, there have been various problems in the conventional developer remaining amount detection. SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems in a developer supply device for supplying a developer from a developer cartridge to a developing unit.

[0016]

An image forming apparatus according to the present invention which solves the above problems has an image forming apparatus having a developing means for developing an electrostatic latent image formed on an image carrier with a developer. In the apparatus, a developer storage unit that stores the developer, a developer transport unit that transports the developer from the developer storage unit to the developing unit, and a developer transport amount that is transported by the developer transport unit is detected. A developer conveyance amount detecting unit and a developer conveyance amount detected by the developer conveyance amount detecting unit are integrated, and when the accumulated amount of the developer reaches a predetermined value or more stored in advance, a developer empty signal is output. Control means for outputting.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Prior to the description of an embodiment of the present invention, the structure and operation of a color printer as an example of an image forming apparatus according to the present invention will be described with reference to the sectional view of FIG.

This color printer superimposes each color toner image sequentially formed on an image carrier, transfers the color image on recording paper once at a transfer section to form a color image, and then separates the image by separating means. This is a color image forming apparatus of a method of peeling off from a surface of a carrier.

In FIG. 1, reference numeral 10 denotes a photosensitive drum serving as an image carrier, which is grounded and driven to rotate clockwise. 1
1 is a scorotron charger, and 12 is a PCL (pre-charging static eliminator). Reference numeral 13 denotes an image exposure unit 13 that performs image exposure based on an image signal, and includes a laser diode, a polygon mirror, an fθ lens, a cylindrical lens, a reflection mirror, and the like, and performs main scanning. A latent image is formed by (sub-scan).

Around the periphery of the photosensitive drum 10, a developing device 20Y containing a two-component developer composed of a toner such as yellow (Y), magenta (M), cyan (C), black (K) and a carrier, respectively. , 20M, 20C, and 20K are provided. Developing units 20Y, 20
Since M, 20C, and 20K have substantially the same configuration, these developing devices will be described as a developing device 20 as a representative. In the figure, reference numeral 21 denotes a developing device casing, 22 denotes a developing device carrier (developing sleeve), and 23 denotes a developer replenishing port opened at an upper portion of the developing device casing 21.

First, the development of the first color yellow is performed by a developing sleeve 22 which contains a magnet and rotates while holding a developer by a developing unit 20Y. AC is applied to the gap between the developing sleeve 22 and the photosensitive drum 10 in the developing area.
The bias _VAC and the DC bias _VDC are superimposed and applied,
Visualization (reversal development) with a yellow developer is performed.

After the visualization of the first color is completed, the process enters the magenta image forming process of the second color, and the uniform charging is again performed by the scorotron charger 11, and the latent image based on the image data of the second color is image-exposed. 13 and a developing unit 20M
Performs magenta development.

The same image forming process as that for the second color magenta is performed for the third color cyan and the fourth color black, and a visible image of four colors is formed on the peripheral surface of the photosensitive drum 10.

Each of the developing units 20Y, 20M, 20C, 2
A developer replenishing device 40 for controlling and replenishing each new color developer at 0K includes a cartridge mounting unit 41 for detachably mounting a plurality of developer cartridges (hereinafter, referred to as cartridges) 30 and each of the cartridges 30. The developer storage unit 42 temporarily stores the developer, and a plurality of developer transport units 43 that transport the developer in the developer storage unit 42 to the developing devices 20Y, 20M, 20C, and 20K. In the developer supply port 23, the developer transported from the cartridge 30 via the developer storage means 42 and the developer transport means 43 is supplied into the developing device 20 from the developer supply port 22.

On the other hand, the half-roller 5
One transfer material (transfer paper or the like) p carried out through 1 is
Paper is fed to the transfer area by a pair of paper feed rollers 52 and 53 and a pair of registration rollers. In the transfer area, the transfer device 55 is pressed against the peripheral surface of the photosensitive drum 10 in synchronization with the transfer timing, and the multi-color image is collectively transferred while holding the fed transfer material p.

Next, the transfer material p is neutralized by the separator 56, separated from the peripheral surface of the photosensitive drum 10 and conveyed to the fixing device 57, where the toner is welded by heating and pressing the heat roller and the pressure roller. , Paper discharge rollers 58A, 58
The sheet is discharged onto a sheet discharge tray 59 outside the apparatus via B. The transfer device 55 is retracted and separated from the peripheral surface of the photosensitive drum 10 after the transfer material p has passed, to prepare for the formation of the next toner image.

On the other hand, the photosensitive drum 1 from which the transfer material p is separated
In the case of 0, after the charge is removed by the charge remover 14, the residual toner is removed and cleaned by the cleaning device 15, and the charge is removed by the PCL 12 and charged by the scorotron charger 11 again, so that the next image forming process is started.

FIG. 2 shows the cartridges 30Y, 30M, 3
0K, 30K and developer storage means 42Y, 42M, 42
C, 42K and developing units 20Y, 20M, 20C, 20K
It is a perspective view which shows a part of. Cartridge mounting means 41
Are four cartridges 30Y, 30M, 30C, 30
K is installed in parallel on substantially the same plane to make it detachable. When it is detected that the amount of the developer in the developer storage means 42Y, 42M, 42C, and 42K has decreased, the cartridges 30Y, 30M, 30C, and 30K rotate respectively, and each developer in the cartridge becomes a developer. Storage means 42Y, 42
M, 42C, and 42K are supplied. Further, the developing device 20
When the toner concentration detecting means (not shown) detects that the developer concentration in Y, 20M, 20C, and 20K has decreased, the developer in developer storing means 42Y, 42M, 42C, and 42K is transferred to developer conveying means 43Y. , 43M, 43C, 4
The developing devices 20Y, 20M, 20C, and 20K are supplied via the 3K. These cartridges 30Y, 30M, 30C, and 30K have substantially the same configuration, and will be hereinafter referred to as cartridge 30.

FIG. 3 shows the developer storage means 42 with the cartridge 30 mounted on the cartridge mounting means 41,
FIG. 4 is a cross-sectional view of a developer conveying unit 43.

A rotational force transmitting member 44 is rotatably supported on an upright wall surface of the developer storage means 42 on the side facing the opening 321 of the cartridge 30. Torque transmitting member 4
Inside the cartridge 4, at a position facing the opening 321 of the cartridge 30, a lid 45 for opening and closing the developer supply device and a coil spring 46 are loaded. A gear 61 for the cartridge is provided at one shaft end of the torque transmitting member 44.
Has been fixed. The cartridge rotation gear 61 is driven and rotated by a drive source and a drive transmission unit described later. The developer contained in the container body 31 of the cartridge 30 is supplied from the opening 321 to the supply port 44 of the rotational force transmitting member 44.
1 and is stored in the hopper of the developer storage means 42.

The cartridge 30 is rotated by the rotation transmitting member 44 and the developer is supplied to the developer storage means 42. However, when a certain amount of the developer is received, the developer is not supplied even if the cartridge 30 rotates. If the cartridge 30 continues to rotate in this state, no problem occurs.

The developer stored in the hopper of the developer storage means 42 is fed into a transport screw 431 fixed to a transport screw gear (developer transport means gear) 432 connected to a drive source described later. The developer is conveyed in the developer conveying means 43 and supplied to the developing device 20.

FIG. 4 is a front view of the drive transmission means of the developer replenishing device viewed from the direction A in FIG.

Drive gear G1 connected to drive motor M1
And a sun gear 63Y, which will be described later, are coaxially and integrally fixed, supported by a fixed support shaft 62Y fixed to the housing 601, and rotatable. The driving gear G1 meshes with and rotates an idler gear G2 that rotates freely on the same axis as the cartridge gear 61Y. The idler gear G2 meshes with an idler gear G4 that rotates freely on the same axis as the cartridge gear 61M via an intermediate gear G3, and rotates the idler gear G4. The idler gear G4 meshes with an idler gear G6 that rotates freely coaxially with the cartridge gear 61C via an intermediate gear G5, and rotates the idler gear G6. The idler gear G6 meshes with an idler gear G8 that rotates freely coaxially with the cartridge gear 61K via an intermediate gear G7 and rotates the idler gear G8.

A swing plate 64Y is swingably supported on the fixed support shaft 62Y of the first drive transmission means 60Y. A planetary gear 65Y is rotatably supported by the rocking plate 64Y. The planetary gear 65Y meshes with a sun gear 63Y supported on a fixed support shaft 62Y. Rocking plate 64
When Y swings around the fixed support shaft 62Y, the planetary gear 65Y revolves around the sun gear 63Y.

Below the cartridge gear 61Y, there is provided an intermediate drive gear 66Y rotatably supported by a fixed shaft implanted in the housing 601. This intermediate drive gear 66
Y meshes with the upper cartridge gear 61Y and meshes with the lower transport screw gear 432Y. When the planetary gear 65Y is disengaged from the intermediate drive gear 66Y (shown), the drive rotation is not transmitted and the stopped state is maintained.

The intermediate drive gear 66Y is a planetary gear 65Y.
When the gears mesh with each other, the sun gear 63
Y, the driving rotation is transmitted via the planetary gear 65Y and rotated. When the intermediate drive gear 66Y is rotated, the cartridge gear 61Y meshed with the intermediate drive gear 66Y and the transport screw gear 432Y are driven and rotated. As a result, the cartridge 30Y is rotated via the torque transmitting member 44 connected to the cartridge gear 61Y, and the contained developer is supplied to the developer storage means 42. At the same time, the transport screw 431 is rotated by the drive rotation of the transport screw gear 432Y, and the developer in the developer storage means 42 is supplied to the developing device 20Y.

A gear G10 is provided above the drive transmission means.
A rotating shaft 67 integrally fixed on the shaft of the gear G10,
Revolution restricting means composed of four cams 68Y, 68M, 68C, 68K is arranged. The rotation shaft 67 is rotatably supported by a housing 601 of the drive transmission means. Four cams 68Y, 68M, 68 are provided on the axis of the rotating shaft 67.
C and 68K are fixed. The gear G10 is connected to a drive motor M2, for example, a stepping motor, and
7 is rotated. The cam 68 (Y, M, C, K) driven by the drive motor M2 and the rocking plate 64 (Y, M, C, K) driven by the drive motor M1 constitute a developer supply mechanism switching unit. ing.

FIG. 5 is a perspective view showing the planetary gear revolution restricting member and the drive transmitting means.

On the peripheral surface of the cam 68Y, a flat portion 681A orthogonal to the rotating shaft 67 and a notch 681B are formed. The other cams 68M, 68C, 68K also have the same shape as the cam 68Y, but are arranged such that the phases of the notches 681B are shifted by 90 °.

The locking portion 641Y is the flat portion 68 of the cam 68Y.
When in contact with 1A, the planetary gear 65Y does not mesh with the intermediate drive gear 66Y. Therefore, the drive rotation is not transmitted to the gear 61 </ b> Y for the cartridge and the gear 432 </ b> Y for the transport screw.

The rotating shaft 67 is rotated 90 ° by the driving motor M2.
The cam 68 (Y, M, C, K), which is intermittently rotated by 90 ° and is arranged with a phase shift of 90 ° on the axis of the rotating shaft 67,
Locking portion 64 at each end of rocking plate 64 (Y, M, C, K) Y
1 (Y, M, C, K). For example, when the rotation angle of the rotation shaft 67 is 0 ° at the initial position, the locking portion 641Y is engaged with the notch 681B of the cam 68Y. At a rotation angle of 90 °, the locking portion 641M engages with the notch 681B of the cam 68M. At a rotation angle of 180 °, the cam 68C
The engaging portion 641C is engaged with the notch portion 681B. At a rotation angle of 270 °, the locking portion 641K engages with the notch 681B of the cam 68K.

The intermittent rotation of the rotary shaft 67 can be performed by switching means such as a cam mechanism, a Geneva mechanism, or a crank mechanism in addition to the pulse drive by the stepping motor.

Referring again to FIG. 4, the second drive transmitting means 60M includes a fixed support shaft 62M, a sun gear 63M, and a swing plate 6M.
4M, planetary gear 65M, intermediate drive gear 66M, cam 68
M, and has the same configuration as the first drive transmission means 60M. The third drive transmission means 60C also includes a fixed support shaft 62.
C, sun gear 63C, rocking plate 64C, planetary gear 65C,
It comprises an intermediate drive gear 66C and a cam 68C, and has the same configuration as the first drive transmission means 60M. Similarly, the fourth drive transmission means 60K also includes a fixed support shaft 62K, a sun gear 63K, a rocking plate 64K, a planetary gear 65K, an intermediate drive gear 66K, and a cam 68K. It has the same configuration.

FIG. 6 shows that only the third drive transmission means 60C engages the notch 681B of the cam 68C with the locking portion 641C at the tip of the rocking plate 64C, and the rocking plate 64C is fixed to the fixed support shaft 62C. , The planetary gear 65C revolves around the sun gear 63C and meshes with the intermediate drive gear 66C. In this state, the cartridge gear 6 meshed with the intermediate drive gear 66C
1C and the conveyance screw gear 432C are driven and rotated. As a result, the cartridge 30C and the transport screw 431C are rotated, and the developer in the cartridge 30C is supplied to the developer storage means 42C and further supplied to the developing device 20C.

Other drive transmission means 60Y, 60M, 60K
In any case, the rotation is not transmitted to the transport screw 431 (Y, M, K), and the developer is not supplied.

FIG. 6 is a block diagram showing a first embodiment of the developer remaining amount detecting device according to the present invention.

Referring to FIG.
The encoders 71Y, 71M, 71C, and 71K are connected to Y, 432M, 432C, and 432K, respectively, and the number of rotations of each of the conveying screw gears 432 (Y, M, C, and K) is counted by a counter of the control unit 70. Then, when the count reaches a predetermined count, an empty signal is output, and the display means 72 is displayed to replace the corresponding cartridge 30 (Y, M, C, K). A plurality of counters set for each color developer include encoders 71Y,
By receiving the input signals from 71M, 71C and 71K, the value of the counter is increased by one. The counter accumulates the count number for each color,
It stores the value and keeps the integrated value even when the power is turned off.

Conveying screw 431 (Y, M, C, K)
Since the replenishment amount per rotation is substantially constant, the number of rotations of each transport screw 431 (Y, M, C, K) causes the development in each developer storage means 42 (Y, M, C, K) to proceed. If the agent runs out or is set first, the conveying screw 431
Since the actual number of operations of (Y, M, C, K) is counted, it is possible to accurately detect the remaining amount of the developer without variation between machines.

The predetermined count number set for each color is determined by the amount of developer to be conveyed per rotation of the conveying screw gear 432 (Y, M, C, K),
It can be determined based on the developer capacity of (Y, M, C, K). That is, in one image formation, the amount of the developer that is consumed in a large amount is set to be large in the amount of the developer to be conveyed per rotation of the gear, so that the predetermined count number set in advance is set to be small. In addition, a developer that is used in a large amount, such as the black developer K, is generally stored in a cartridge 30K that is larger than the developer cartridges 30 (Y, M, C,) of the other colors. Become.
Further, the set count number is determined by each developer storage unit 42Y,
The set value also changes depending on the developer storage capacities of 42M, 42C, and 42K and the lengths of the developer conveying units 43Y, 43M, 43C, and 43K. Therefore, the set count number may be variably set in the memory unit in advance for each developer storage capacity of the developer supply device of the image forming apparatus or for each use of the image forming apparatus.

The control means of the present invention preferably outputs a signal corresponding to the count number every time the counter value increases in addition to the empty signal, and causes the display means to display the remaining amount of the developer according to the count number. More preferably, the number of remaining prints is displayed on the display means based on the output count number and the number of prints so far.

The image forming apparatus which has received the output of the empty signal or an apparatus (for example, a computer) connected to the image forming apparatus is connected to each of the developer storage means 42 (Y, M, C,
K) indicating that the developer needs to be replenished, indicating that the cartridge 30 (Y, M, C, K) needs to be replaced,
An empty operation such as a display indicating that the image forming process of the image forming apparatus is stopped is performed.

The above empty operation is performed by display means such as displaying on the operation panel of the printer main body or copier main body shown in FIG. 1, or displaying on a display of a personal computer connected to the printer.

In the first embodiment shown in FIG. 6, an encoder 71 (Y, M, C, K) is installed in each of the gears 432 (Y, M, C, K) for the transport screw, and the actual transport is performed. The number of rotations of the screw gear 432 (Y, M, C, K) is counted by the control means 70, so that the amount of the developer transported is detected, and when the count reaches a predetermined count, an indication is given to replace the developer cartridge. However, as a second embodiment, as shown in FIG. 7, encoders 71 (Y, M, C, K) are installed on all the conveying screw gears 432 (Y, M, C, K). Without, sun gear 63
(Y, M, C, K), planetary gear 65 (Y, M, C,
K), rocking plate 64 (Y, M, C, K), cam 68 (Y,
M, C, K), etc., one encoder 71 is installed on the driving gear G1 at the most upstream of the drive transmission means of the planetary gear revolution restricting member, and the number of rotations of the driving gear G1 and the cam 68 (Y,
The number of rotations of the cartridge 30 (Y, M, C, K) of the color is counted by the control means 70 from the set position of (M, C, K). (Y, M, C, K) is displayed on the display means 72 to be exchanged. In the second embodiment, by reducing the number of encoders, the number of components is further reduced and the wiring is simplified as compared with the first embodiment.

FIG. 8 is a flow chart showing an example of counting and controlling the amount of developer transported in the second embodiment of the present invention shown in FIG.

The control means 70 detects the rotation angle of the driving motor M2 or the rotation angle of the rotation shaft 67 (S131).

When the detected rotation angle is such that the planetary gear 65Y meshes with the intermediate drive gear 66Y, in the embodiment shown in FIG. 5, the rotation angle of the rotation shaft 67 is 0 °.
At ± 30 ° (S1Y), the count of the encoder 71 is added to the integrated value of Y and stored in the nonvolatile memory 75 (S1Y).
2Y).

Subsequently, the integrated value of Y is compared with a specified value (S3).
Y) If the integrated value of Y exceeds the specified value, an empty signal is output (S4Y), and if it is less than the specified value, the process is terminated.

In S1Y, the rotation angle of the rotation shaft 67 is 0.
90 ° ± 30 ° other than ° ± 30 °, that is, 66M is 65 °
It is determined whether or not M is engaged (S1M). If so, the count of the encoder 71 is added to the integrated value of M and stored in the nonvolatile memory 75 (S2M). S3Y, S4
Similar to Y, the integrated value of M is compared with a specified value, and if it is equal to or larger than the specified value, an empty signal is output. In S1M, 9
When the angle is other than 0 ° ± 30 °, similarly to S1Y to S4Y, whether the rotation angle of the rotating shaft 67 is 180 ° ± 30 ° (S
1C), it is determined whether the angle is 270 ° ± 30 ° (S1K). If the condition is satisfied, the values are added to the integrated value of C and the integrated value of K, respectively, and the specified value is compared with each integrated value.

When the rotation angle does not correspond to any of the above, an error is displayed and the image forming operation is stopped or the correcting operation is performed, and the SIE processing (error display, image forming stop,
Correction operation).

FIG. 9 is a block diagram showing control of an image forming apparatus provided with a developer supply device. A third embodiment of the image forming apparatus according to the present invention will be described below.

The transport screw 431 (Y, M, C,
Conveying speed of the developer by _{K) (V 1, V 2} , V 3, V 4)
Speed detection means 73 (Y, M, C, K) for detecting
To each encoder 71 (Y, M, C, K) shown in FIG.
Provided in place of The conveying screw 431 (Y, M,
C, K) and the conveying screw 431 (Y, M,
C, K) developer transport speed (V ₁ , V ₂ , V ₃ , V ₄ )
The transport speed detecting means 73 (Y, M, C, K) can be constituted by a rotating speed detecting means (for example, a tachometer or other tachometer).

Further, the transport screw 431 (Y,
M, C, and K) are provided. The transport speeds (V ₁ , V ₂ , V ₃ ,...) Of each developer detected by the transport speed detecting means 73 (Y, M, C, K).
When the control unit 70 determines that the integrated value obtained by integrating the product of V ₄ ) and each operation time detected by the time counting unit 74 is equal to or greater than a specified value stored in the nonvolatile memory, Indication for replenishing developer in developer storage means 42 (Y, M, C, K), cartridge 30 (Y, M, K)
C, K), and stops the image forming process of the image forming apparatus, and drives the empty operation means such as a warning or display to that effect. For example, every 10 msec to 1 sec, the transport screw 431 (Y, M, C,
K), the rotation speed of the transfer speed detecting means 73 (Y, M,
C, K), the rotational speed during operation of the image forming apparatus is integrated and stored in the non-volatile memory 75, and a warning is displayed when the integrated value of the value becomes equal to or greater than a first predetermined value. Further, when the cartridge 30 (Y, M, C, K) is not replaced and becomes equal to or more than the second predetermined value, the operation of the image forming apparatus is immediately stopped, and a warning and display to that effect. FIG.
The conveyance speed detecting means 73 is used instead of the encoder 71 shown in FIG.
Is provided, and the rotational speed of the driving gear G1 and the cam 68
From the set position of (Y, M, C, K), the product of the transport speed (V ₁ , V ₂ , V ₃ , V ₄ ) of each developer and each operation time detected by the timer 74 is integrated. The control means 70 determines that the integrated value obtained is equal to or greater than the specified value stored in the nonvolatile memory.
The developer empty operation means,
, Can also be driven.

In the above embodiment, the conveying screw has been described as an example of the developer conveying means. However, the present invention is not limited to this, and can be applied to other developer conveying means. . For example, the amount of the developer transported by the developer transporting unit, which is applied to a developer transporting unit such as a rotor or a rotating impeller that weighs a certain amount of developer and rotates, and detects the amount of developer transported by the developer transporting unit. It is also possible to integrate the developer conveyance amount detected by the detecting means, and to execute a developer empty operation such as a developer supply display when the integrated amount of the developer becomes a predetermined value or more.

According to the above embodiment, the conventional problems can be solved, and the remaining amount of the developer can be detected accurately and easily.

[0066]

As described above, according to the present invention, without using the developer remaining amount detecting means in the developer storing means,
By directly detecting the amount of development carried by the developer carrying means, the developer empty can be accurately detected irrespective of the amount of developer stored in the developer storage unit, and a complicated electric adjustment time and An excellent effect is obtained that it is possible to contribute to a reduction in manufacturing cost by reducing the number of parts.

[Brief description of the drawings]

FIG. 1 is a cross-sectional configuration diagram of a color printer as an example of an image forming apparatus according to the present invention.

FIG. 2 is a perspective view showing a cartridge, developer storage means, and a part of a developing device.

FIG. 3 is a cross-sectional view of a developer storage unit in a state where the cartridge is mounted on the cartridge mounting unit, and a developer conveying unit.

FIG. 4 is a front view of a drive transmission unit of the developer supply device.

FIG. 5 is a perspective view showing a planetary gear revolution restricting member and a drive transmission unit.

FIG. 6 is a configuration diagram showing a first embodiment of a developer remaining amount detection device according to the present invention.

FIG. 7 is a configuration diagram showing a second embodiment of the developer remaining amount detection device according to the present invention.

FIG. 8 is a flowchart illustrating control of a developer conveyance amount.

FIG. 9 is a block diagram illustrating control of an image forming apparatus including a developer supply device.

FIG. 10 is a characteristic diagram illustrating a correlation between a timing of a developer supply signal and a rotation speed of a conveyance screw.

FIG. 11 is a characteristic diagram showing a relationship between a supply signal time and a conveying screw rotation time.

[Explanation of symbols]

Reference Signs List 20 developing device (developing means) 20 (Y, M, C, K) developing device 30 (Y, M, C, K) developer container (cartridge) 40 developer replenishing device 41 cartridge mounting means 42 (Y, M) , C, K) Developer storage means (developer hopper) 43 (Y, M, C, K) Developer transport means 431 (Y, M, C, K) Transport screw 432 (Y, M, C, K) Gear for transport screw 60 (Y, M, C, K) Drive transmission means (drive system) 61 (Y, M, C, K) Gear for cartridge rotation 62 (Y, M, C, K) Fixed support shaft 63 ( Y, M, C, K) Sun gear 64 (Y, M, C, K) Oscillating plate 65 (Y, M, C, K) Planetary gear 66 (Y, M, C, K) Intermediate drive gear 67 rotation Shaft 68 (Y, M, C, K) Cam 70 Control means 71 (Y, M, C, K) Rotation speed detecting means Encoder) 72 display unit 73 (Y, M, C, K) transport speed detecting means 74 timer means 75 nonvolatile memory M1, M2 drive motor

Claims (6)

[Claims] 1. An image forming apparatus having a developing unit for developing an electrostatic latent image formed on an image carrier with a developer, wherein the developer storing unit stores the developer, and the developing unit stores the developer. Developer transporting means for transporting the developer to the developing means, developer transporting amount detecting means for detecting the amount of developer transported by the developer transporting means, and developing detected by the developer transporting amount detecting means When the accumulated amount of the developer reaches a predetermined value or more stored in advance,
An image forming apparatus comprising: a control unit that outputs a developer empty signal. 2. The image forming apparatus according to claim 1, further comprising display means for displaying that the developer is to be supplied to the developer storage means based on a developer empty signal output from the control means. Item 2. The image forming apparatus according to Item 1. 3. The image forming apparatus according to claim 1, further comprising: a detachable developer storage container for replenishing developer to said developer storage means, and wherein said developing means is configured to output said developer based on a developer empty signal output from said control means. The image forming apparatus according to claim 1, further comprising a display unit that indicates that the agent container is to be replaced. 4. An image forming apparatus according to claim 1, wherein said image forming apparatus has an image forming stop control unit for controlling to stop an image forming operation by said image forming apparatus based on said developer empty signal. An image forming apparatus according to claim 1. 5. The developer conveying means includes a developer conveying member for conveying a developer from a developer storing means to the developing means by a rotation operation, and the developer conveying amount detecting means includes a developer conveying member. 2. The image forming apparatus according to claim 1, wherein a developer conveyance amount is detected by detecting a rotation speed of the image forming apparatus. 6. The developer conveying amount detecting unit includes: a conveying speed detecting unit that detects at least a conveying speed of the developer in the developer conveying unit; and a timing unit that detects an operation time of the developer conveying unit. The image forming apparatus according to claim 1, wherein: