JP2009103906A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of quickly bringing a refill container into a standby state after the replacement of the refill container and capable of achieving a cost reduction by performing estimation of an amount of remaining developer and detection of attachment/detachment of the refill container by means of a single sensor. <P>SOLUTION: The image forming apparatus includes: the refill container 1 that is detachably attached, refills a storage device with developer, stored in it, by the drive of a rotation drive mechanism 4 changed in the number of rotations according to the amount of remaining developer, and is provided with a magnet 10 in the rotating section of the rotation drive mechanism 4; and an estimating means 10 that estimates an amount of remaining developer stored in the refill container 1. The estimating means 10 has: a contactless element 10b that is disposed opposite the magnet 10a when the supply container 1 is attached and that is operable in a magnetic field; and a first control means 10c that detects attachment/detachment of the refill container 1 based on the operation of the contactless element 10b and that estimates the amount of remaining developer stored in the refill container 1. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image forming apparatus such as an electrophotographic apparatus that forms an image by developing a latent image formed on an image carrier such as a photoconductor with a developing device.

  2. Description of the Related Art Conventionally, in an image forming apparatus that forms an image by developing a latent image formed on an image carrier such as a photoreceptor with a developing device, toner (developer) in the developing device is used as the image forming process proceeds. Since it is consumed, it is necessary to supply toner.

  Toner is replenished into the developing device by transferring the toner from the toner replenishing container containing the toner into the developing device.

Conventionally, an image forming apparatus provided with a means for detecting attachment / detachment of a toner replenishing container and detecting the amount of remaining toner has been proposed in order to immediately enable image formation (standby state) after replacing the toner replenishing container. (Patent Document 1 and Patent Document 2).
JP 2000-347492 A JP-A-11-149212

  However, in the above conventional example, a plurality of sensors are used to detect attachment / detachment of the toner replenishing container and to detect the remaining amount of toner, which is costly. Further, since the attachment / detachment of the toner replenishing container is mechanically detected, the mechanism becomes complicated, and the cost of the members and the like is increased.

  In view of the above, the present invention can reduce the cost by making it possible to quickly enter the standby state after replacing the replenishing container, and to predict the remaining amount of developer and detect the attachment / detachment of the replenishing container with one sensor. An object of the present invention is to provide an image forming apparatus capable of performing the above.

  In order to achieve the above object, an image forming apparatus of the present invention is detachably mounted with a developing device for attaching a developer to an image carrier, a storage device for storing the developer supplied to the developing device, Replenish the developer stored in the storage device by driving a rotational drive mechanism whose rotational speed changes according to the remaining amount of the developer, and a magnet is provided in the rotating part of the rotational drive mechanism And a predicting means for predicting the remaining amount of developer contained in the replenishing container, the predicting means being disposed close to the magnet when the replenishing container is mounted and operable with a magnetic field A non-contact element; and a first control unit that detects attachment / detachment of the replenishing container based on an operation of the non-contact element and predicts a remaining amount of the developer stored in the replenishing container. Features.

  According to the present invention, after replacement of the replenishing container, it is possible to quickly enter the standby state, and the remaining amount of developer can be predicted and the attachment / detachment detection of the replenishing container can be performed with one sensor, thereby reducing costs. Can do.

  Hereinafter, an example of an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic sectional view for explaining an image forming apparatus which is an example of an embodiment of the present invention.

  As shown in FIG. 1, an image forming apparatus 100 according to this embodiment includes a photoconductor 101 as an image carrier, and an electrostatic latent image is formed on the surface of the photoconductor 101 by a charger or an exposure device (not shown). After the formation, a developer is attached to the electrostatic latent image by the developing device 102 to form a visible image.

  The visible image is transferred by the transfer device 109 to the transfer material S stored in the paper feed cassette 103 and supplied to the photosensitive member 101 via the paper feed roller 105, the transport rollers 106 and 107, and the like.

  Thereafter, the transfer material S is transported to the fixing device 111 by transport means provided close to the exhaust heat fan 113, and is heated and pressed by the fixing device 111. The transfer material S on which the visible image is fixed by the fixing device 111 is discharged to the outside of the device, and the image formation is completed.

  In FIG. 1, reference numeral 102 b denotes a developing sleeve disposed in the developing device 102 so that toner (developer) is attached to the electrostatic latent image on the photoconductor 101. Reference numeral 114 denotes a control circuit of the image forming apparatus 100, which controls the entire apparatus. Further, reference numeral 115 denotes a liquid crystal type operation display unit provided on the operation panel or the like.

  FIG. 2 is a cross-sectional view of the toner replenishing container 1, the storage device 2, and the developing device 102 along a plane parallel to the paper surface. FIG. 3 is a cross-sectional view taken along line AA in FIG.

  As shown in FIGS. 2 and 3, the toner replenishing container 1 contains toner, and a toner discharge screw (rotary drive mechanism) 4 and an electromagnet 10a are arranged. The electromagnet 10 a is attached to a rotating blade that is a rotating portion of the toner discharge screw 4.

  Further, an auxiliary member 6a is projected from a side portion of the toner replenishing container 1 in the longitudinal direction (left and right direction in FIG. 3). The auxiliary member 6a is detachably mounted on a mounting portion 6b provided in the apparatus 100 so that when the toner replenishing container 1 is mounted, an electromagnet 10a and a reed switch 10b described later are disposed close to each other and face each other. Is done.

  The toner replenishing container 1 communicates with the storage device 2 through the toner replenishing port 1a when mounted in the apparatus 100. The toner is supplied to the storage device 2 through the replenishing port 1a as the toner discharge screw 4 in the toner replenishing container 1 rotates.

  The toner replenished to the storage device 2 is uniformly leveled in the longitudinal direction (left and right direction in FIG. 3) by the leveling means 5, and the inner wall sequentially facing from the inner wall (right inner wall in FIG. 3) side on the replenishing port 1a side. It is conveyed to the side (the left inner wall in FIG. 3).

  Further, the toner discharge screw 4 is driven by a DC motor (not shown) in the apparatus 100, and the DC motor controls a circuit so as to change the rotation speed of the toner discharge screw 4 according to the amount of toner in the toner replenishing container 1. 114.

  When a normal copying operation is performed, the rotation speed of the toner discharge screw 4 is controlled so that a predetermined amount of toner is supplied from the toner replenishing container 1 to the storage device 2 via the replenishing port 1a. .

  Further, when supplying a certain amount of toner to the storage device 2, the toner discharge screw 4 rotates at a set constant rotation number and supplies the toner to the storage device 2 when the remaining amount of toner is large. On the other hand, when the toner remaining amount is low, the toner discharge screw 4 scrapes the toner from the back side (left side in FIG. 3) of the toner replenishing container 1 and supplies it to the storage device 2.

  At this time, it takes time to scrape off the toner, and it takes time if the toner discharge screw 4 rotates at a set constant rotation speed. Therefore, when the remaining amount of toner is low, the control circuit 114 controls the DC motor so as to increase the rotation speed of the toner discharge screw 4 to shorten the time, and stores the toner in the same time as when the remaining amount of toner is large. The apparatus 2 can be supplied.

  FIG. 4 is a graph showing the relationship between the rotation speed of the toner discharge screw 4 and the remaining amount of toner when the same amount of toner is supplied to the storage device 2.

  As can be seen from FIG. 4, the toner discharge screw 4 reduces the rotation speed when the remaining amount of toner in the toner replenishing container 1 is large, and increases the rotation speed when the remaining amount of toner is small. Control is performed to supply toner to the storage device 2.

  Next, a toner remaining amount prediction circuit (prediction unit) 10 that predicts the amount of toner in the toner replenishing container 1 will be described with reference to FIG.

  The toner remaining amount prediction circuit 10 includes a reed switch (non-contact element) 10b and a magnet detection control circuit (first control means) 10c. Here, in the present embodiment, the toner remaining amount prediction circuit 10 detects attachment / detachment of the toner replenishing container 1 and predicts the toner remaining amount.

  The reed switch 10b is a non-contact element that can be operated by a magnetic field. When the toner replenishing container 1 is mounted, the reed switch 10b is positioned outside the toner replenishing container 1 so as to face the electromagnet 10a attached to the rotating blades of the toner discharge screw 4. Installed.

  The magnet detection control circuit 10c executes a predetermined process according to the ON / OFF operation of the reed switch 10b.

  FIG. 5A is a diagram illustrating a state where the auxiliary member 6 a of the toner replenishing container 1 is mounted on a mounting portion 6 b provided in the apparatus 100.

  In FIG. 5A, the electromagnet 10a approaches the reed switch 10b, the reed switch 10b is turned off, and the magnet detection control circuit 10c detects that the toner replenishing container 1 is mounted, and controls the apparatus 100. Transmit to circuit 114.

  When the toner replenishing container 1 is removed from the apparatus 100, the electromagnet 10a is separated from the reed switch 10b and the reed switch 10b is turned on, and the magnet detection control circuit 10c detects that the toner replenishing container 1 has been removed. To the control circuit 114 of the apparatus 100.

  FIG. 6 is a time chart for explaining the toner remaining amount predicting operation by the toner remaining amount predicting circuit 10.

  First, when the auxiliary member 6a of the toner replenishing container 1 is mounted on the mounting portion 6b provided in the apparatus 100, as described above, the state is as shown in FIG. 5A, and the reed switch 10b is turned off. .

  When the copy operation is started, the toner discharge screw 4 starts to rotate in the direction of the arrow in FIG. Then, the electromagnet 10a attached to the rotating blades of the toner discharge screw 4 also rotates, away from the reed switch 10b, and the reed switch 10b is turned from OFF to ON. Further, when the rotating blades of the toner discharge screw 4 make a round, the electromagnet 10a returns to the position shown in FIG. 5A, and the reed switch 10b is turned from ON to OFF.

  In such an operation, the time required for the reed switch 10b to turn off during one rotation of the toner discharge screw 4 is measured by the magnet detection control circuit 10c and stored in a predetermined storage area.

  For example, in FIG. 6A, the magnet detection control circuit 10c measures a time T1 until the reed switch 10b is turned off during one rotation of the toner discharge screw 4, and stores it in a predetermined storage area. The magnet detection control circuit 10c counts how many times T1 has been repeated during a pre-stored time T0, and compares the count value C1 with a pre-stored count value C.

  Here, as described above, when the remaining amount of toner in the toner replenishing container 1 is small, the control circuit 114 of the image forming apparatus 100 controls the DC motor so as to increase the rotation speed of the toner discharge screw 4 and time. To shorten.

  Therefore, as shown in FIG. 6B, the time T1 from the ON to OFF of the reed switch 10b during one rotation of the toner discharge screw 4 measured by the magnet detection control circuit 10c is shortened, and is T0 time. Count number, that is, the count value C1 increases.

  When the count value C1 exceeds the count value C stored in advance, the magnet detection control circuit 10c instructs the control circuit 114 of the apparatus 100 of a prediction result indicating no toner. Thus, in this embodiment, it is possible to predict the absence of the remaining amount of toner based on the rotation speed of the toner discharge screw 4.

  On the other hand, when the control circuit (second control unit) 114 of the image forming apparatus 100 receives the instruction of the prediction result of no toner from the magnet detection control circuit 10c, it acquires the print counter value, and the print counter value It is determined whether or not a predetermined set value has been reached.

  If the control circuit 114 determines that the print counter value has reached a predetermined set value, the control circuit 114 finally determines that there is no remaining toner, and the operation display unit indicates that there is no remaining toner. 115 (notification), etc., prompting the user to replace the toner replenishing container 1.

  FIG. 7 is a flowchart for explaining an operation example of the remaining toner amount prediction circuit 10, and FIG. 8 is a flowchart for explaining an operation example of the control circuit 114.

  First, an operation example of the toner remaining amount prediction circuit 10 will be described with reference to FIG.

  In step S1, when the electromagnet 10a approaches the reed switch 10b and the reed switch 10b is turned off, the magnet detection control circuit 10c detects that the toner replenishing container 1 has been installed, and then goes to the control circuit 114 of the apparatus 100. Send.

  In step S2, the magnet detection control circuit 10c counts the time T1 as the toner discharge screw 4 in the toner replenishing container 1 rotates, and records the count value C1 in a storage area (not shown).

  Next, in step S3, the magnet detection control circuit 10c determines whether or not the time T from the start of recording of the count value C1 has reached a predetermined time T0. If T = T0, the count value C1 is determined. Is compared with the count value C stored in advance (step S4).

  When the count value C1 exceeds the count value C, the magnet detection control circuit 10c determines that there is no toner, and instructs the control circuit 114 of the determination result (step S5).

  Next, an exemplary operation of the control circuit 114 will be described with reference to FIG.

  First, in step S11, when the control circuit 114 receives a detection signal indicating that the toner replenishing container 1 is mounted from the magnet detection control circuit 10c, it starts copying in step S12 and controls the DC motor in step S13. Then, the rotation of the toner discharge screw 4 is started.

  Next, in step S14, the control circuit 114 determines whether or not there is an instruction for the prediction result without toner from the magnet detection control circuit 10c. Obtain (step S15).

  Next, in step S16, the control circuit 114 determines whether or not the acquired printer counter value has reached a preset setting value. If not, the control circuit 114 returns to step S14. The process proceeds to step S17.

  In step S <b> 17, the control circuit 114 displays “no toner” on the operation display unit 115 and prompts the user to replace the toner replenishing container 1.

  As described above, in the present embodiment, when the toner replenishing container 1 is replaced, the replacement of the toner replenishing container 1 can be confirmed by the control circuit 114 of the image forming apparatus 100. After that, it is possible to quickly enter a standby state.

  Further, since the remaining amount of toner can be predicted and the attachment / detachment detection of the toner replenishing container 1 can be performed with one sensor, the cost can be reduced.

  In addition, this invention is not limited to what was illustrated to the said embodiment, In the range which does not deviate from the summary of this invention, it can change suitably.

1 is a schematic cross-sectional view for explaining an image forming apparatus which is an example of an embodiment of the present invention. FIG. 4 is a cross-sectional view taken along a plane parallel to the paper surface of the toner replenishing container, the storage device, and the developing device. It is the sectional view on the AA line of FIG. FIG. 6 is a graph showing the relationship between the rotation speed of a toner discharge screw and the remaining amount of toner when the same amount of toner is supplied to a storage device. 4A and 4B are diagrams for explaining a toner remaining amount prediction circuit that predicts the amount of toner in a toner replenishing container. FIG. 5A illustrates a state in which the toner replenishing container is attached, and FIG. 5B illustrates a state in which the toner replenishing container is removed. is there. FIG. 10 is a time chart for explaining a toner remaining amount predicting operation by a toner remaining amount predicting circuit. FIG. 6 is a flowchart for explaining an operation example of a toner remaining amount prediction circuit. It is a flowchart for demonstrating the operation example of a control circuit.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Toner replenishing container 1a Replenishing port 2 Storage device 4 Toner discharge screw 5 Leveling means 10 Toner remaining amount prediction circuit 10a Electromagnet 10b Reed switch 10c Magnet detection control circuit 100 Image forming apparatus 101 Photoconductor 102 Developing apparatus 102a Developing container T Toner

Claims (4)

A developing device for attaching a developer to the image carrier;
A storage device that stores the developer supplied to the developing device is detachably mounted, and the developer housed therein is stored by driving a rotation driving mechanism that changes the number of rotations according to the remaining amount of the developer. Replenishing the apparatus, and a replenishing container provided with a magnet in the rotating part of the rotation drive mechanism;
Predicting means for predicting the remaining amount of developer accommodated in the replenishing container,
The predicting means is disposed close to the magnet when the refill container is mounted, and a non-contact element operable by a magnetic field;
And a first control unit that detects attachment / detachment of the replenishing container based on an operation of the non-contact element and predicts a remaining amount of the developer stored in the replenishing container. Forming equipment.   The image forming apparatus according to claim 1, wherein the magnet is attached to a rotary blade of the rotary drive mechanism.   According to the predicted result of the remaining amount of the developer by the first control means, a print counter value is acquired, and when the print counter value reaches a predetermined set value, there is no developer. The image forming apparatus according to claim 1, further comprising: a second control unit that makes a determination and notifies the user of the determination result.   The first control means detects that the replenishing container is mounted when the magnet approaches the non-contact element and the non-contact element is turned OFF, and the magnet is separated from the non-contact element. The image forming apparatus according to claim 1, wherein when the non-contact element is turned on, it is detected that the refill container is removed.

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