JP2024076098A - Image forming device - Google Patents

Abstract

The present invention aims to perform detection operations necessary for usability at low cost and with high accuracy.
[Solution] The device comprises a cartridge having a memory 130, a control unit which controls image forming operations based on information read from the memory 130, a memory terminal 131 which is provided in the device main body and abuts against the memory 130 when the cartridge is attached to the device main body and moves away from the memory 130 when the cartridge is removed from the device main body, a judgment member 132 which is provided in the device main body and moves away from the memory terminal 131 when the cartridge is attached and abuts against the memory terminal 131 when the cartridge is removed, and a memory communication circuit which communicates between the memory 130 and the control unit via the memory terminal 131 when the cartridge is attached and which cuts off communication with the memory 130 when the cartridge is removed, and the control unit judges whether the cartridge is attached to the device main body based on a signal output from the memory communication circuit.
[Selected figure] Figure 3

Description

The present invention relates to an image forming apparatus, for example, a printing apparatus, particularly an image forming apparatus such as a copying machine, a laser beam printer, or a facsimile machine.

Conventionally, there are image forming devices using the following types of electrophotographic image formation process. For example, there is a process cartridge type in which the photoconductor and the process means acting on the photoconductor are integrated into a cartridge that can be attached and detached to the device body as a configuration for supplying toner. Another example is a supply type in which the process means is installed in the device body and only the toner is replenished. The characteristics of the supplied toner may change after the user purchases the device body due to factors such as changes in manufacturing conditions. Therefore, a memory is used that stores correction values for various controls of the image formation process in order to perform the image formation process appropriately in accordance with the toner characteristics.

In the process cartridge method, the memory is attached to the cartridge. The correction value stored in the memory is read after the user opens the cartridge replacement door of the device body, replaces the cartridge, and closes the door, after the image forming device confirms that the cartridge is installed. In order to perform such a read process, the image forming device is equipped with a door sensor for detecting the opening and closing of the door, as well as a cartridge presence sensor for detecting the presence or absence of the cartridge. If there is no cartridge presence sensor, printing will be performed without the cartridge, resulting in the discharge of blank paper, or in some cases, paper will not be transported properly and paper jams will occur, resulting in reduced usability. For this reason, detecting the presence or absence of the cartridge is important for usability. However, once the presence of the cartridge is confirmed, the cartridge presence sensor is not used until the door is opened. For this reason, for example, Patent Document 1 proposes a configuration in which the presence or absence of the cartridge is detected by using the paper presence sensor used during the printing operation. Also, for example, Patent Document 2 proposes a configuration in which the presence or absence of the cartridge is detected by using high voltage feedback. By adopting such a configuration, costs have been reduced.

In the refill method, the memory is attached to the toner refill container. The correction value stored in the memory is read when the user opens the cover of the toner refill port and attaches the toner refill container to the toner refill port. An example of such a configuration is that described in Patent Document 3. However, in a configuration in which the cover of the toner refill port or the refill container itself blocks the discharge port, normal printing operations cannot be performed if the user opens the cover of the refill port during printing. For this reason, a toner refill port cover open/close sensor is required to appropriately interrupt printing.

JP 2005-345939 A JP 2002-333812 A JP 2022-076821 A

However, in the process cartridge method, in order to use the cartridge presence sensor as a paper presence sensor used during printing, a mechanical flag for cartridge presence detection needs to be placed near the paper transport path. Because rollers and parts for image formation are densely packed near the transport path, this can lead to an increase in size depending on the configuration of the device body. Also, in a configuration that uses high-voltage feedback to detect the presence of a cartridge, the high-voltage feedback can change depending on the conditions of the outside temperature and humidity of the device body, making accurate detection impossible. In the refill method, users usually keep the refill port cover closed, and providing a dedicated sensor for the cover open/close sensor leads to an increase in size and cost of the device.

The present invention was made under these circumstances, and aims to perform the detection operations necessary for usability at low cost and with high accuracy.

To solve the above problems, the present invention has the following configuration.

(1) An image forming device that forms an image on a transfer material, comprising: a cartridge that is detachably mounted on a device body of the image forming device, contains a developer, and has a memory unit that stores information used in an image forming operation; a control unit that reads the information from the memory unit and controls the image forming operation based on the read information; a terminal member that is mounted on the device body and abuts against the memory unit when the cartridge is mounted on the device body and separates from the memory unit when the cartridge is removed from the device body; a contact member that is mounted on the device body and separates from the terminal member when the cartridge is mounted on the device body and abuts against the terminal member when the cartridge is removed from the device body; and a communication unit that communicates between the memory unit and the control unit via the terminal member when the cartridge is mounted on the device body and that cuts off communication with the memory unit when the cartridge is removed from the device body, and the control unit determines whether the cartridge is mounted on the device body based on a signal output from the communication unit.

(2) An image forming apparatus that forms an image on a transfer material, the image forming apparatus includes a storage unit that stores information used in an image forming operation, a supply port to which a supply container containing developer for supply is attached, and a storage unit that stores the developer supplied through the supply port; a control unit that reads the information from the storage unit and controls the image forming operation based on the read information; an opening/closing member that has a contact member and is in an open state when the supply container is attached to the supply port and in a closed state when the supply container is removed from the supply port to cover the supply port; a terminal member that is provided in the main body of the image forming apparatus and contacts the storage unit when the supply container is attached to the supply port and contacts the contact member when the opening/closing member is closed; and a communication unit that communicates between the storage unit and the control unit via the terminal member when the supply container is attached to the supply port and that cuts off communication with the storage unit when the supply container is removed from the supply port, the control unit determining the open state or the closed state of the opening/closing member based on a signal output from the communication unit.

The present invention makes it possible to perform detection operations necessary for usability at low cost and with high accuracy.

1 is a cross-sectional view of a process cartridge type image forming apparatus according to first and second embodiments; Block diagram of a control system of a process cartridge system according to the first and second embodiments. FIG. 13 is a diagram showing the relationship between the cartridge insertion state and the memory terminals in the first embodiment; FIG. 13 is a diagram showing the relationship between the cartridge insertion state and the memory communication circuit in the first embodiment. Flowchart of detecting the presence or absence of a cartridge in the first embodiment FIG. 13 is a diagram showing a configuration of a memory terminal connection member in another communication method according to the first embodiment; FIG. 13 is a diagram showing the relationship between the cartridge insertion state and the memory terminals in the second embodiment; Flowchart of detecting the presence or absence of a cartridge in the second embodiment 1 is a cross-sectional view of an image forming apparatus of a toner refilling system according to a third embodiment of the present invention; Block diagram of a control system for a toner replenishment method according to the third embodiment. Flowchart of supply port cover opening/closing detection in embodiment 3

The following describes in detail the embodiments of the present invention with reference to the drawings.

<Image forming apparatus>
FIG. 1 is a cross-sectional view of a process cartridge type image forming apparatus 100 of the first embodiment. The image forming apparatus 100 of the first embodiment is an electrophotographic image forming apparatus that performs a fixing process of pressing and heating the toner image formed by performing a series of image forming processes of charging, exposing, and developing a photosensitive drum. A transfer material P such as paper is fed by a paper feed roller 110, and is separated and conveyed one by one by a separation roller pair 111 so as not to overlap multiple transfer materials P. Then, the transfer material P is conveyed to a transfer roller 124 by a conveying roller 112. A toner image formed on a photosensitive drum 121 inside the cartridge 120 by an image forming process described later is transferred to the transfer material P by the transfer roller 124. Then, the transfer material P is pressurized and heated by a fixing device 113 to fix the unfixed toner image, and then passes through a discharge roller 114 and is discharged.

Next, the image formation process carried out within the cartridge 120 will be described. First, the photosensitive drum 121, which is made of an organic photosensitive material or an amorphous silicon photosensitive material and rotates in a clockwise direction (arrow in the figure), has its surface uniformly charged by the charging roller 122, which is a charging means. Next, the charged photosensitive drum 121 is exposed to laser light emitted from a laser optical box (not shown) that forms an electrostatic latent image, and an electrostatic latent image is formed. The electrostatic latent image is developed by the developing roller 123, which carries and transports the toner, which is the developer, and finally it is transferred to the transfer material P by the transfer roller 124.

The cartridge 120 is configured to be easily detachable from the image forming apparatus 100 as an integrated unit that contains at least toner, and in the first embodiment, the photosensitive drum 121, charging roller 122, developing roller 123, and toner are integrated into one unit. The cartridge 120 is also equipped with a memory 130, which is a storage unit. The memory 130 stores information used in the image forming operation, such as correction values for control when forming an image by charging, developing, and transferring in the image forming process, and correction values for the temperature to be heated by the fixing unit 113.

The image forming apparatus 100 is provided with an opening 150 for accessing the inside of the apparatus in order to attach and detach the cartridge 120. The image forming apparatus 100 also includes a door 140, which is an openable member that is in an open state when the cartridge 120 is attached or detached inside the image forming apparatus 100 through the opening 150, and is in a closed state when the opening 150 is covered. The memory 130 comes into contact with a memory terminal 131 inside the image forming apparatus 100 when the user opens the door 140, which can be opened and closed from the position 140a to the position 140b, and inserts the cartridge 120 through the opening 150. The memory terminal 131, which is a terminal member, is provided in the apparatus main body, and comes into contact with the memory 130 when the cartridge 120 is attached to the apparatus main body, and is separated from the memory 130 when the cartridge 120 is removed from the apparatus main body. Here, when the door 140 is in the position 140a, the door 140 is in a closed state, and when the door 140 is in the position 140b, the door 140 is in an open state. The door sensor 141, which is a detection means, detects whether the door 140 is open or closed.

Even if the cartridge 120 is not properly inserted, the user can close the door 140, which pushes the cartridge 120 in and causes the memory 130 to abut against the memory terminal 131. The image forming device 100 is also provided with a cartridge presence/absence determination member 132 (hereinafter, referred to as the determination member 132) that abuts against the memory terminal 131 when the cartridge 120 is not installed. The determination member 132, which is an abutting member, is provided in the device body and is separated from the memory terminal 131 when the cartridge 120 is installed in the device body (the state shown in FIG. 1). The determination member 132 abuts against the memory terminal 131 when the cartridge 120 is removed from the device body. Note that the image forming device to which the present invention can be applied is not limited to the image forming device 100 shown in FIG. 1, and may be any cartridge-type image forming device.

<Control block diagram>
2 is a control block diagram of embodiment 1. A control unit 200 of the image forming apparatus 100 is a microprocessor that controls the entire image forming apparatus 100, and has the following three main functions.

A cartridge management unit 210 that determines whether or not the cartridge 120 is present and reads the memory 130.
An image forming control unit 220 that controls the high voltage, the scanner, and the fixing based on the data read from the memory 130 by the cartridge management unit 210 in order to form an image on the transfer material P and heat fix it.
A paper transport control unit 230 that controls paper transport

The cartridge management unit 210 is connected to a door sensor 141 for detecting that the user has completed replacement of the cartridge 120, and a memory communication circuit 211 for communicating with the memory 130. The memory communication circuit 211, which is a communication unit, communicates between the memory 130 and the control unit 200 via the memory terminal 131 when the cartridge 120 is attached to the device body. The memory communication circuit 211 also cuts off communication with the memory 130 when the cartridge 120 is removed from the device body. The cartridge management unit 210 of the control unit 200 determines whether the cartridge 120 is present and controls reading of the memory 130. The cartridge management unit 210 determines whether the cartridge 120 is present in the device body based on a signal output from the memory communication circuit 211.

The image forming control unit 220 is connected to a high voltage generating circuit 221, a scanner/laser control circuit 222, and a temperature control circuit 223. The high voltage generating circuit 221 is a circuit for forming a mirror toner image on the photosensitive drum 121 and transferring it to the transfer material P. The scanner/laser control circuit 222 is a circuit for outputting the on/off of the laser light emitted from the laser optical box. The temperature control circuit 223 is a circuit including a heater for thermally fixing the toner in the fixing unit 113 and a thermistor for detecting the heater temperature. The paper transport control unit 230 is connected to a motor 231, which is the drive source for the entire image forming apparatus 100, and a paper feed solenoid 232 for controlling the paper feed roller 110.

<Memory electrode, memory terminal, judgment member>
Next, the operation of the memory 130, memory terminal 131, and determination member 132 when inserting the cartridge 120 will be described with reference to Fig. 3(a). Specifically, the memory terminal 131 is made up of memory terminals 131a, 131b, 131c, and 131d. The memory 130 has an IC chip built in, and includes a memory electrode 300 for communicating with the image forming apparatus 100. Specifically, the memory electrode 300 is made up of memory electrodes 300a, 300b, 300c, and 300d.

When the cartridge 120 is inserted into the image forming device 100, the memory electrodes 300a, 300b, 300c, and 300d come into contact with the memory terminals 131a, 131b, 131c, and 131d arranged inside the image forming device 100, respectively. This allows communication between the image forming device 100 and the memory 130 using four signal lines. Note that in the first embodiment, the four memory terminals 131a to 131d come into contact with the four memory electrodes 300a to 300d, allowing communication using four signal lines, but this is not limiting. The number of memory terminals 131 and memory electrodes 300 may be determined according to the number of signal lines required.

When the cartridge 120 is not inserted in the image forming device 100, the memory terminal 131 is in contact with the determination member 132. The determination member 132 includes a conductive memory terminal connection member 301 (hereinafter referred to as the connection member 301). When the determination member 132 is in contact with the memory terminal 131, the memory terminal 131c and the memory terminal 131d are in an electrically short-circuited state. FIG. 3A shows a state in which the cartridge 120 is not inserted in the image forming device 100 main body (apparatus main body), the determination member 132 is in contact with the memory terminal 131, and the memory terminal 131c and the memory terminal 131d are in a short-circuited state by the connection member 301. The direction in which the cartridge 120 is inserted is illustrated in FIG. 3C as the insertion direction.

The determination member 132 is pushed by a spring (not shown) in a counterclockwise direction around the top as shown in the cross-sectional view of FIG. 3(b) from the side. Therefore, when the cartridge 120 is not inserted in the image forming device 100, the determination member 132 maintains a state of abutting against the memory terminal 131. When the cartridge 120 is inserted, the determination member 132 rotates in a clockwise direction (arrow in FIG. 3(c)) in conjunction with the movement of the cartridge 120 by being pushed by the cartridge 120. As a result, after passing through the state of FIG. 3(c), as shown in FIG. 3(d), the determination member 132 moves away from the memory terminal 131, the short state of the memory terminal 131 is released, and the memory terminal 131 and the memory electrode 300 come into abutment. Here, FIG. 3(c) shows a state in which neither the memory electrode 300 nor the determination member 132 abuts against the memory terminal 131.

<Memory communication circuit>
Next, the memory communication circuit 211 that communicates with the memory 130 will be described with reference to FIG. 4. In the first embodiment, I2C (Inter-Integrated Circuit) communication is used for communication with the memory 130, with the control unit 200 as the master and the memory 130 as the slave. Here, the memory communication circuit 211 has a first communication line 211a connected to a power source, a second communication line 211c used for at least the control unit 200 to receive information between the memory 130, and a third communication line 211d that is grounded. Note that 211b is the fourth communication line. The second communication line 211c and the fourth communication line 211b are connected to the first communication line 211a via a resistor. The memory terminal 131 has a memory terminal 131a that is a first terminal member, a memory terminal 131c that is a second terminal member, and a memory terminal 131d that is a third terminal member. Note that the memory terminal 131b corresponds to the fourth terminal member. The memory terminal 131a is a terminal connected to the first communication line 211a. The memory terminal 131c is a terminal connected to the second communication line 211c. The memory terminal 131d is a terminal connected to the third communication line 211d. The memory terminal 131b is a terminal connected to the fourth communication line 211b. In the first embodiment, the cartridge management unit 210 determines whether or not the cartridge 120 is attached based on a signal input via the second communication line 211c.

First, FIG. 4(a) shows the memory communication circuit 211 corresponding to FIG. 3(d) in which the cartridge 120 is fully inserted. The communication circuit of the memory terminal 131a is the Vcc power supply for the control unit 200 and memory 130 to operate, and is fixed at 3.3 V. The communication circuit of the memory terminal 131b is an I2C clock circuit, and is driven by the control unit 200, which is the master, via an open drain output. The clock circuit is set to high level by the pull-up circuit, except when the control unit 200 outputs a low level during communication, as both the control unit 200 and memory 130 are in a high impedance (Hi-Z) state.

The communication circuit of the memory terminal 131c is an I2C data circuit, and both the control unit 200 and the memory 130 output in synchronization with the clock by open drain output. When communication is not taking place, the control unit 200 and the memory 130 are both in a high impedance state, so the data circuit is maintained at a high level by a pull-up circuit. The communication circuit of the memory terminal 131d is a ground (GND) for the operation of the control unit 200 and the memory 130, and is fixed at 0V. With the above circuit configuration, the control unit 200 can communicate with the memory 130 using the clock circuit and data circuit, and read the contents of the memory 130. In addition, the terminals of the control unit 200 and the memory 130 are Vcc, I2C_CLOCK, I2C_DATA, and GND, respectively.

Next, FIG. 4(b) shows the memory communication circuit 211 corresponding to FIG. 3(b) in which the cartridge 120 is completely removed. As described above, the determination member 132 includes a conductive connection member 301, so that the memory terminals 131c and 131d are shorted. In other words, the determination member 132 shorts the memory terminals 131c and 131d when in contact with the memory terminal 131. This causes the data circuit to go low.

FIG. 4(c) shows the memory communication circuit 211 corresponding to FIG. 3(c), in which the cartridge 120 is being attached or detached and neither the memory electrode 300 nor the determination member 132 is in contact with the memory terminal 131. When the control unit 200 is not communicating, the data circuit is put into a high impedance state, so the data circuit goes to a high level by the pull-up circuit.

In this way, when the control unit 200 is not reading information from the memory 130 and the cartridge 120 is attached to the device body, the memory communication circuit 211 outputs a high-level signal to the control unit 200 via the second communication line 211c (Figure 4(a)). When the cartridge 120 is removed from the device body, the memory communication circuit 211 outputs a low-level signal to the control unit 200 via the second communication line 211c (Figure 4(b)). The cartridge management unit 210 determines whether the cartridge 120 is attached to the device body based on the signal output from the memory communication circuit 211.

<Determining whether or not a cartridge is present>
Finally, a method for determining the presence or absence of the cartridge 120 by the cartridge management unit 210 using the data circuit of the memory communication circuit 211 will be described with reference to the flowchart of Fig. 5. Since the presence or absence of the cartridge 120 does not change when the door 140 is closed, this flowchart is executed only once after the door sensor 141 determines that the door 140 has been opened. More specifically, the cartridge management unit 210 of the control unit 200 determines the presence or absence of the cartridge 120 when the door sensor 141 detects that the door 140 has changed from an open state to a closed state.

In step (hereinafter referred to as S) 501, the cartridge management unit 210 uses the door sensor 141 to determine whether or not the door 140 is closed. If the cartridge management unit 210 determines in S501 that the door 140 is not closed, the process returns to S501, and if it determines that the door 140 is closed, the process proceeds to S502. In S502, the cartridge management unit 210 determines whether or not the input level of the data circuit (I2C_DATA) including the memory terminal 131c of the memory communication circuit 211 is high.

If the cartridge management unit 210 determines in S502 that the data circuit is at a high level (S502 Yes), the process proceeds to S503. At this time, the memory communication circuit 211 is in the state shown in FIG. 4A, and in S503 the cartridge management unit 210 determines that the cartridge 120 is inserted into the device body, i.e., that a cartridge is present. In S504, the cartridge management unit 210 communicates with the memory 130 via the memory communication circuit 211, reads out correction values and the like stored in the memory 130, and ends the process.

If the cartridge management unit 210 determines in S502 that the data circuit is not at a high level, i.e., that the data circuit is at a low level (S502 No), the process proceeds to S505. At this time, the memory communication circuit 211 is in the state shown in FIG. 4(b), and in S505 the cartridge management unit 210 determines that the cartridge 120 has not been inserted, i.e., that there is no cartridge, and ends the process.

This method of determination uses digital circuits to determine whether the cartridge 120 is present or not, allowing for highly accurate determinations to be made regardless of the environment in which the image forming device 100 is placed.

<Modification>
In the first embodiment, the I2C communication is used as the communication method with the memory 130, but the communication method is not limited to this. For example, high-active UART (Universal Asynchronous Receiver Transmitter) communication may be used. Here, the terminals of the control unit 200 (and the memory 130) are Vcc, UART_TRANS, UART_RECEIVE, and GND. GND is connected to the data input circuit.

In this case, the connection member 301 shorts the data input circuit (UART_RECEIVE) and the Vcc power supply as shown in FIG. 6, and the data input circuit goes high. This makes it possible to determine that a cartridge is present when the data input circuit is low, and that a cartridge is not present when the data input circuit is high.

In the case of FIG. 6, the judgment member 132, which is an abutting member, is provided in the device body, and is separated from the memory terminal 131 when the cartridge 120 is attached to the device body, and is abutted against the memory terminal 131 when the cartridge 120 is removed from the device body. In FIG. 6, the second communication line 211c is connected to the third communication line 211d via a resistor. The judgment member 132 shorts the memory terminal 131c and the memory terminal 131a when the cartridge 120 is removed from the device body. The memory communication circuit 211 outputs a low-level signal to the control unit 200 via the second communication line 211c when the cartridge 120 is attached to the device body while the control unit 200 is not reading information from the memory 130. The memory communication circuit 211 outputs a high-level signal to the control unit 200 via the second communication line 211c when the cartridge 120 is removed from the device body.

In the first embodiment, the terminals of the memory terminal 131 provided on the image forming device 100 are shorted together, but rather than simply shorting them together to reduce power consumption, other circuit configurations, such as adding a resistor, may be added to the cartridge presence/absence determination member.

In the first embodiment, the determination member 132 is brought into contact with the memory terminal 131, but this is not limiting. For example, an intermediate terminal for bringing the determination member 132 into contact with the memory terminal 131 may be provided between the control unit 200 and the memory terminal 131, and a mechanical flag or the like may be used to bring the determination member 132 into contact with or separate from the intermediate terminal in conjunction with the insertion state of the cartridge 120.

In the first embodiment, the state of the data circuit is checked as soon as the door 140 is closed, but this is not limited to the above. For example, in preparation for a case in which the memory 130 continues to output a low level to the data circuit in the immediately previous communication, a communication reset process such as a process of sending a dummy clock or a process of temporarily cutting off the power supply to the memory 130 may be added immediately before the communication. This may ensure that the memory 130 opens the data circuit.

In the first embodiment, the configuration for determining the presence or absence of the cartridge 120 in the cartridge system is described, but this is not limiting. For example, in the refill system, a memory terminal provided in the refill port for communicating with a memory attached to the refill toner pack and a member equivalent to the cartridge presence/absence determining member that abuts against and separates from the memory terminal in conjunction with the attachment and detachment of the refill toner pack may be used. This may allow the attachment and detachment of the refill toner pack to the device body to be detected. As described above, by using the configuration of the first embodiment, it is possible to use an input circuit for communication with an existing memory to determine the presence or absence of a cartridge with high accuracy and without being dependent on the environment, without providing a dedicated sensor.

As described above, according to the first embodiment, the detection operation required for usability can be performed accurately and at low cost.

In the first embodiment, a method for determining the presence or absence of a cartridge 120 was described by connecting (shorting) the data circuit of the memory communication circuit 211 to GND. With this method, when the cartridge 120 is not present, a current always flows from the pull-up power supply of the data circuit to GND, which increases power consumption. Therefore, in the second embodiment, a method for detecting the presence or absence of a cartridge 120 with less power consumption even when the cartridge 120 is not present is described.

<Memory electrode, memory terminal, judgment member>
The cross-sectional view and the control block diagram of the image forming apparatus 100 of the second embodiment are the same as those of the first embodiment, and therefore the description thereof will be omitted. The communication method with the memory 130 uses I2C communication, and the configuration of the memory 130 and the circuit configuration from the control unit 200 to the memory terminal 131 are also the same as those of the first embodiment, and therefore the description thereof will be omitted. The configuration of the determination member 132a and the memory communication circuit 211 of the second embodiment will be described with reference to FIG. 7.

In the second embodiment, as shown in FIG. 7A, a conductive connection member 701 is disposed on the judgment member 132a. The connection member 701 is disposed on the judgment member 132a so as to short the memory terminal 131b used by the control unit 200 for clock output (I2C_CLOCK) and the memory terminal 131c used for data input/output (I2C_DATA). Therefore, when the memory terminal 131 and the judgment member 132 are in contact with each other, the memory communication circuit 211 is in the state shown in FIG. 7B. That is, the memory terminal 131b and the memory terminal 131c are in a shorted state. In this state, when the control unit 200 outputs a low level to the clock circuit of the memory terminal 131b, the data circuit of the memory terminal 131c becomes low level. On the other hand, when the control unit 200 puts the clock circuit into a high impedance state, the data circuit becomes high level due to the pull-up circuit between the clock circuit and the data circuit.

In this way, the judgment member 132a, which is an abutting member, is provided in the device body, and is separated from the memory terminal 131 when the cartridge 120 is attached to the device body, and abuts against the memory terminal 131 when the cartridge 120 is removed from the device body. The memory communication circuit 211 has a fourth communication line 211b that is different from the second communication line 211c and is connected to the first communication line 211a. The memory terminal 131 has a memory terminal 131b that is a fourth terminal member connected to the fourth communication line 211b. The judgment member 132a shorts the memory terminal 131c and the memory terminal 131d when the cartridge 120 is removed from the device body. The memory communication circuit 211 outputs the following signal when the control unit 200 is not reading information from the memory 130. First, when a low-level signal is output from the control unit 200 via the fourth communication line 211b, the memory communication circuit 211 outputs a high-level signal to the control unit 200 via the second communication line 211c if the cartridge 120 is attached to the device body. When the cartridge 120 is removed from the device body, the memory communication circuit 211 outputs a low-level signal to the control unit 200 via the second communication line 211c.

<Determining whether or not a cartridge is present>
Next, a method for determining the presence or absence of the cartridge 120 by the cartridge management unit 210 using the clock circuit and data circuit of the memory communication circuit 211 will be described with reference to the flowchart of Fig. 8. Since the presence or absence of the cartridge 120 does not change while the door 140 is closed, this flowchart is executed only once after the door sensor 141 determines that the door 140 is open.

In S801, the cartridge management unit 210 uses the door sensor 141 to determine whether the door 140 is closed. If the cartridge management unit 210 determines in S801 that the door 140 is not closed, the process returns to S801, and if the cartridge management unit 210 determines that the door 140 is closed, the process proceeds to S802. In S802, the cartridge management unit 210 switches the clock circuit (I2C_CLOCK) including the memory terminal 131b to a low level output. In S803, the cartridge management unit 210 determines whether the input level of the data circuit (I2C_DATA) including the memory terminal 131c is high level.

If the cartridge management unit 210 determines in S803 that the data circuit is at a high level (S803 Yes), this is the state shown in FIG. 4A, and determines in S804 that the cartridge 120 is inserted (cartridge present). In S805, the cartridge management unit 210 returns the clock circuit to its original high impedance (Hi-Z) setting. In S806, the cartridge management unit 210 reads out the correction values and the like stored in the memory 130, and ends the process.

If the cartridge management unit 210 determines in S803 that the data circuit is at a low level (S803 No), this is the state shown in FIG. 7B, and in S807 it determines that the cartridge 120 has not been inserted (no cartridge). In S808, the cartridge management unit 210 returns the clock circuit to its original high impedance (Hi-Z) setting, and ends the process.

In this way, after it is determined that the cartridge 120 is not present, both the clock circuit and the data circuit are put into a high impedance state, thereby preventing the generation of a steady leak current from the pull-up circuit to GND. This makes it possible to detect the presence or absence of the cartridge 120 with lower power consumption.

Note that, although the second embodiment has been described using I2C communication as the communication method with memory 130, the communication method is not limited to this. For example, UART communication may be used, and even if communication with memory is a two-wire system, it can be applied by connecting data transmission and data reception and switching the output of the transmission circuit to make the input for data reception different from the input when a cartridge is inserted. As described above, by using the configuration of the second embodiment, it is possible to use the input circuit and output circuit for communication with existing memory and to determine the presence or absence of a cartridge with high accuracy and without being dependent on the environment, without providing a dedicated sensor.

As described above, according to the second embodiment, the detection operation required for usability can be performed accurately and at low cost.

<Image forming apparatus>
A replenishing type image forming apparatus 900 according to the third embodiment will be described with reference to the external view of Fig. 9(a) and the cross-sectional views of Fig. 9(b) and (c). The image forming apparatus 900 according to the third embodiment is an electrophotographic image forming apparatus that performs a series of image forming processes, such as charging, exposing, and developing, on a photosensitive drum, transfers the formed toner image onto a transfer material P, and performs a fixing process of applying pressure and heat.

A transfer material P such as paper is fed by a feed roller 910 and separated and transported one by one by a pair of separation rollers 911 to prevent multiple sheets of transfer material P from being fed in duplicate. The transfer material P is then transported to a transfer roller 924 by a transport roller 912. A toner image formed on the photosensitive drum 921 by an image formation process described below is transferred to the transfer material P by the transfer roller 924. The transfer material P is then pressurized and heated by a fixing device 913 to fix the toner image, and is then discharged through discharge rollers 914.

Next, the image formation process will be described. First, the photosensitive drum 921, which is made of an organic photosensitive material or an amorphous silicon photosensitive material and rotates in a clockwise direction (arrow in the figure), has its surface uniformly charged by a charging roller 922, which is a charging means. Next, the charged photosensitive drum 921 is exposed to laser light emitted from a laser optical box (not shown) that forms an electrostatic latent image, and an electrostatic latent image is formed. The electrostatic latent image is developed by a developing roller 923 that carries and transports toner, which is a developer, and finally it is transferred to a transfer material P by a transfer roller 924.

The image forming apparatus 900 includes a toner container 925 that is a storage unit. The toner container 925 includes a toner refill port 920 (refill port) and stores toner refilled through the toner refill port 920. A toner refill container 933 (refill container) that refills toner to the toner container 925 is attached to the toner refill port 920. The toner refill container 933 includes a memory 930 that stores information used in the image forming operation. The image forming apparatus 900 also includes a refill port cover 940 that is an opening/closing member. The refill port cover 940 includes a cover opening/closing determination member 932 that is an abutting member. The refill port cover 940 is in an open state when the toner refill container 933 is attached to the toner refill port 920, and is in a closed state when the toner refill container 933 is removed from the toner refill port 920 and covers the toner refill port 920.

When the supply port cover 940, which can be opened and closed from position 940a to position 940b, is open, the toner supply container 933 can be set in the toner supply port 920 as shown in FIG. 9C, toner can be supplied to the toner container 925. When the supply port cover 940 is at position 940a, the supply port cover 940 is closed, and when the supply port cover 940 is at position 940b, the supply port cover 940 is open. The supply port cover 940 also serves as a tray for discharging the printed transfer material P, and when the supply port cover 940 is open, the discharge port for the transfer material P is blocked. Therefore, the image forming apparatus 900 is configured not to continue printing operations with the supply port cover 940 open.

A memory 930 is attached to the toner supply container 933, and various correction values and the like are stored in the same manner as in the first embodiment. The memory 930 comes into contact with a memory terminal 931 at the toner supply port 920 when the user opens the supply port cover 940 and sets the toner supply container 933. The back surface of the supply port cover 940 is provided with a cover open/close determination member 932 (hereinafter referred to as the determination member 932) that comes into contact with the memory terminal 931 when the supply port cover 940 is closed.

<Control block diagram>
10 is a control block diagram of the third embodiment. The image forming control unit 220 and the paper transport control unit 230 are the same as those in the first embodiment, so their explanation will be omitted, and only the supply management unit 1010 will be explained. The supply management unit 1010 is connected to a memory communication circuit 211 for communicating with the memory 930. The supply management unit 1010 determines whether the supply port cover 940 is open or closed, and controls reading of the memory 930.

The memory communication circuit 211 uses I2C communication as in the first embodiment. The memory 930 has the same configuration as the memory 130 in the first embodiment, the memory terminal 931 has the same configuration as the memory terminal 131, and the determination member 932 has the same configuration as the determination member 132. That is, the memory terminal 931 has four memory terminals corresponding to the memory terminals 131a to 131d. The determination member 932 has a memory terminal connection member corresponding to the memory terminal connection member 301 that shorts the two memory terminals corresponding to the memory terminals 131c and 131d when it comes into contact with the memory terminal 131. Therefore, the data circuit of the memory communication circuit 211 is at a low level when the supply port cover 940 is closed, and at a high level when the supply port cover 940 is open.

The memory terminal 931 is provided on the main body of the image forming apparatus 900, and abuts against the memory 930 when the toner supply container 933 is attached to the toner supply port 920, and abuts against the determination member 932 when the supply port cover 940 is closed. The memory communication circuit 211 communicates between the memory 930 and the control unit 200 via the memory terminal 931 when the toner supply container 933 is attached to the toner supply port 920. The memory communication circuit 211 cuts off communication with the memory 930 when the toner supply container 933 is removed from the toner supply port 920. The supply management unit 1010 of the control unit 200 judges whether the supply port cover 940 is open or closed based on the signal output from the memory communication circuit 211.

<Determining whether or not a cartridge is present>
Finally, a method for the supply management unit 1010 to determine whether the supply port cover 940 is open or closed using the data circuit of the memory communication circuit 211 will be described with reference to the flowchart of FIG. 11. In S1101, the supply management unit 1010 determines whether the input level of the data circuit of the memory communication circuit 211 is low or not. If the supply management unit 1010 determines in S1101 that the data circuit is low (S1101 Yes), the process proceeds to S1102. In S1102, the supply management unit 1010 determines that the memory terminal 931 and the determination member 932 are in contact with each other and that the supply port cover 940 is closed (supply port cover closed), and returns the process to S1101.

If the supply management unit 1010 determines in S1101 that the data circuit is not at a low level, i.e., is at a high level (S1101 No), the process proceeds to S1103. In S1103, the supply management unit 1010 determines that the memory terminal 931 and the judgment member 932 are separated and that the supply port cover 940 is open (supply port cover open). In S1104, the supply management unit 1010 transmits the device address of the memory 930 and determines whether an ACK is returned, i.e., whether there is a communication response.

In S1104, if there is a communication response (S1104 Yes), the supply management unit 1010 advances the process to S1105. In S1105, the supply management unit 1010 determines that the memory terminal 931 and the memory 930 are in contact, that is, the toner supply container 933 is set (supply container present). In S1106, the supply management unit 1010 reads correction values, etc. from the memory 930, and returns the process to S1101.

If the supply management unit 1010 determines in S1104 that there is no communication response (S1104 No), the process proceeds to S1107. In S1107, the supply management unit 1010 determines that the toner supply container 933 is not set (no supply container), and returns the process to S1101. By repeating the above process, the supply management unit 1010 can determine with high accuracy whether the supply port cover 940 is open or closed, even during a printing operation, etc., regardless of the environment in which the image forming device 900 is placed.

Thus, the memory communication circuit 211 has a first communication line connected to a power source, a second communication line used for at least the control unit 200 to receive information between the memory 930, and a grounded third communication line. The memory terminal 931 has a first terminal member connected to the first communication line, a second terminal member connected to the second communication line, and a third terminal member connected to the third communication line. The control unit 200 judges whether the supply port cover 940 is open or closed based on a signal input via the second communication line. The second communication line is connected to the third communication line. The judgment member 932 shorts the second terminal member and the third terminal member when in contact with the memory terminal 931. The memory communication circuit 211 outputs a low-level signal to the control unit 200 via the second communication line when the supply port cover 940 is in a closed state, and outputs a high-level signal to the control unit 200 via the second communication line when the supply port cover 940 is in an open state. The control unit 200 determines whether the refill port cover 940 is open or closed based on a signal output from the memory communication circuit 211. If the control unit 200 determines that the refill port cover 940 is open, it sends a signal to the memory 930 via the memory communication circuit 211, and determines whether the toner refill container 933 is attached to the toner refill port 920 based on the presence or absence of a response signal from the memory 930.

In the third embodiment, an example is described in which the determination member 932 connects the data circuit (I2C_DATA) to GND to detect whether the supply port cover 940 is open or closed, but this is not limiting. As in the second embodiment, a transmission circuit (clock circuit (I2C_CLOCK) in the case of I2C) and a reception circuit (data circuit (I2C_DATA) in the case of I2C) may be connected, and the transmission circuit may be operated only at the timing to determine whether the supply port cover 940 is open or closed to perform detection.

For example, as shown in FIG. 7 of the second embodiment, the following configuration may be used. The memory communication circuit 211 has a fourth communication line different from the second communication line connected to the first communication line. The memory terminal 931 has a fourth terminal member connected to the fourth communication line. The determination member 932 shorts the second terminal member and the fourth terminal member when in contact with the memory terminal 931. When a low-level signal is output from the control unit 200 via the fourth communication line, the memory communication circuit 211 outputs a high-level signal to the control unit 200 via the second communication line if the supply port cover 940 is in the open state. When the supply port cover 940 is in the closed state, the memory communication circuit 211 outputs a low-level signal to the control unit 200 via the second communication line. The control unit 200 determines whether the supply port cover 940 is in the open state or the closed state based on the signal output from the memory communication circuit 211.

In the third embodiment, I2C communication is used as the communication method with the memory, but the communication method is not limited to this. For example, other communication methods such as UART communication may be used.

For example, as shown in FIG. 6 of the first embodiment, the following configuration may be used. The second communication line is connected to the third communication line. The determination member 932 shorts the second terminal member and the first terminal member when in contact with the memory terminal 931. The memory communication circuit 211 outputs a high-level signal to the control unit 200 via the second communication line when the supply port cover 940 is closed. The memory communication circuit 211 outputs a low-level signal to the control unit 200 via the second communication line when the supply port cover 940 is open. The control unit 200 determines whether the supply port cover 940 is open or closed based on the signal output from the memory communication circuit 211.

In the third embodiment, the terminals are shorted together, but rather than simply shorting them together to reduce power consumption, other circuit configurations, such as adding a resistor, may be added to the cartridge presence/absence determination component.

In the third embodiment, the determination member 932 is brought into contact with the memory terminal 931, but this is not limiting. For example, an intermediate terminal for bringing the determination member 932 into contact therewith may be provided between the control unit 200 and the memory terminal 931, and the determination member 932 and the intermediate terminal may come into contact with or separate from each other in conjunction with the open/closed state of the supply port cover 940.

In addition, in preparation for the case where the memory 930 continues to output a low level to the data circuit in the immediately preceding communication, the following may be done. For example, before determining whether the supply port cover 940 is open or closed based on the input of the data circuit, a communication reset process such as a process of sending a dummy clock or a process of temporarily cutting off the power supply to the memory 930 may be added before determining whether the supply port cover 940 is open or closed. Then, the memory 930 may reliably open the data circuit. As described above, by using the configuration of the third embodiment, it is possible to use an input circuit for communication with an existing memory and determine whether the supply port cover is open or closed with high accuracy and independent of the environment without providing a dedicated sensor.

As described above, according to the third embodiment, the detection operation required for usability can be performed accurately and at low cost.

In the above embodiment, the memory communication circuit 211 has four communication lines, the first communication line 211a to the fourth communication line 211d, but is not limited to this. For example, the memory communication circuit may have two communication lines. In this case, one communication line (first communication line) may be used to transmit a signal from the control unit 200 (output side), and the other communication line (second communication line) may be used to input a signal to the control unit 200 (input side). In this case, the memory terminal 131 may have a memory terminal (first terminal member) connected to one communication line and a memory terminal (second terminal member) connected to the other communication line. Then, with the two communication lines shorted by the above configuration, the control unit 200 operates the output side to detect the presence or absence of the cartridge 120 and the opening or closing of the supply port cover 940 based on the signal on the input side. Also, as shown in FIG. 8 (S802), when determining the presence or absence of a cartridge 120 or the opening or closing of the supply port cover 940 based on a signal input via the other communication line, the control unit 200 may output a predetermined signal (e.g., a low-level signal) from one of the communication lines. In this manner, the memory communication circuit may have at least two signal lines, and may be configured to short-circuit the two signal lines (two memory terminals).

100 Image forming apparatus 130 Memory 131 Memory terminal 132 Cartridge presence/absence determination member 200 Control section 210 Cartridge management section 211 Memory communication circuit

Claims (16)

An image forming apparatus for forming an image on a transfer material,
a cartridge that is detachably mounted on a main body of the image forming apparatus, contains a developer, and has a storage unit that stores information used in an image forming operation;
a control unit that reads the information from the storage unit and controls the image forming operation based on the read information;
a terminal member that is provided in the device body, the terminal member being in contact with the storage unit when the cartridge is attached to the device body, and being spaced apart from the storage unit when the cartridge is removed from the device body;
a contact member that is provided in the main body of the apparatus, the contact member being spaced from the terminal member when the cartridge is attached to the main body of the apparatus and being in contact with the terminal member when the cartridge is removed from the main body of the apparatus;
a communication section which performs communication between the storage section and the control section via the terminal member when the cartridge is attached to the device body, and which cuts off communication with the storage section when the cartridge is removed from the device body;
Equipped with
The image forming apparatus according to claim 1, wherein the control unit determines whether or not the cartridge is attached to the main body of the apparatus based on a signal output from the communication unit. the communication unit includes a first communication line connected to a power source, a second communication line used for at least the control unit to receive the information between the communication unit and the storage unit, and a third communication line grounded;
the terminal members include a first terminal member connected to the first communication line, a second terminal member connected to the second communication line, and a third terminal member connected to the third communication line;
2. The image forming apparatus according to claim 1, wherein the control unit determines whether or not the cartridge is mounted based on a signal input via the second communication line. the second communication line is connected to the first communication line,
the abutting member short-circuits the second terminal member and the third terminal member when in contact with the terminal member,
The image forming apparatus according to claim 2, characterized in that when the control unit is not reading the information from the memory unit and the cartridge is installed in the device main body, the communication unit outputs a high-level signal to the control unit via the second communication line, and when the cartridge is removed from the device main body, the communication unit outputs a low-level signal to the control unit via the second communication line. the second communication line is connected to the third communication line;
the abutting member short-circuits the second terminal member and the first terminal member in a state in which the cartridge is removed from the main body of the apparatus,
The image forming apparatus according to claim 2, characterized in that when the control unit is not reading the information from the memory unit and the cartridge is installed in the device main body, the communication unit outputs a low-level signal to the control unit via the second communication line, and when the cartridge is removed from the device main body, the communication unit outputs a high-level signal to the control unit via the second communication line. the communication unit has a fourth communication line different from the second communication line connected to the first communication line,
the terminal member includes a fourth terminal member connected to the fourth communication line,
the contact member short-circuits the second terminal member and the fourth terminal member when the cartridge is removed from the main body of the apparatus,
The image forming apparatus according to claim 2, characterized in that when the control unit is not reading the information from the memory unit and a low-level signal is output from the control unit via the fourth communication line, the communication unit outputs a high-level signal to the control unit via the second communication line if the cartridge is installed in the device main body, and outputs a low-level signal to the control unit via the second communication line if the cartridge is removed from the device main body. the communication unit includes a first communication line used for the control unit to transmit the information to the storage unit, and a second communication line used for the control unit to receive the information to the storage unit,
the terminal member includes a first terminal member connected to the first communication line and a second terminal member connected to the second communication line,
the abutting member short-circuits the second terminal member and the first terminal member in a state in which the cartridge is removed from the main body of the apparatus,
2. The image forming apparatus according to claim 1, wherein the control unit determines whether or not the cartridge is mounted based on a signal input via the second communication line. The image forming device according to claim 6, characterized in that the control unit outputs a predetermined signal from the first communication line when determining whether the cartridge is installed based on a signal input via the second communication line. an opening for attaching and detaching the cartridge;
an opening/closing member that is in an open state when the cartridge is attached or detached through the opening and that is in a closed state when the opening is covered;
A detection means for detecting the open state or the closed state of the opening/closing member;
Equipped with
The image forming apparatus according to any one of claims 1 to 7, characterized in that the control unit determines whether or not the cartridge is installed when the detection means detects that the opening/closing member has changed from the open state to the closed state. An image forming apparatus for forming an image on a transfer material,
a storage section having a storage section for storing information used in an image forming operation, a supply port to which a supply container containing developer for supply is attached, and the storage section stores the developer supplied through the supply port;
a control unit that reads the information from the storage unit and controls the image forming operation based on the read information;
an opening/closing member having an abutting member, the opening/closing member being in an open state when the supply container is attached to the supply port and being in a closed state when the supply container is removed from the supply port to cover the supply port;
a terminal member provided in a main body of the image forming apparatus, the terminal member abutting against the storage unit when the refill container is attached to the refill port and abutting against the abutting member when the opening/closing member is in the closed state;
a communication unit that performs communication between the memory unit and the control unit via the terminal member when the refill container is attached to the refill port, and that cuts off communication with the memory unit when the refill container is removed from the refill port;
Equipped with
The image forming apparatus, wherein the control unit determines whether the opening/closing member is in the open state or the closed state based on a signal output from the communication unit. the communication unit includes a first communication line connected to a power source, a second communication line used for at least the control unit to receive the information between the communication unit and the storage unit, and a third communication line grounded;
the terminal members include a first terminal member connected to the first communication line, a second terminal member connected to the second communication line, and a third terminal member connected to the third communication line;
The image forming apparatus according to claim 9 , wherein the control unit determines whether the opening/closing member is in the open state or the closed state based on a signal input via the second communication line. the second communication line is connected to the first communication line,
the abutting member short-circuits the second terminal member and the third terminal member when in contact with the terminal member,
The image forming apparatus according to claim 10, characterized in that the communication unit outputs a low-level signal to the control unit via the second communication line when the opening/closing member is in the closed state, and outputs a high-level signal to the control unit via the second communication line when the opening/closing member is in the open state. the second communication line is connected to the third communication line;
the abutting member short-circuits the second terminal member and the first terminal member when in contact with the terminal member,
The image forming apparatus according to claim 10, characterized in that the communication unit outputs a high-level signal to the control unit via the second communication line when the opening/closing member is in the closed state, and outputs a low-level signal to the control unit via the second communication line when the opening/closing member is in the open state. the communication unit has a fourth communication line different from the second communication line connected to the first communication line,
the terminal member includes a fourth terminal member connected to the fourth communication line,
the abutting member short-circuits the second terminal member and the fourth terminal member when in contact with the terminal member,
The image forming apparatus according to claim 10, characterized in that when a low-level signal is output from the control unit via the fourth communication line, the communication unit outputs a high-level signal to the control unit via the second communication line if the opening/closing member is in the open state, and outputs a low-level signal to the control unit via the second communication line if the opening/closing member is in the closed state. the communication unit includes a first communication line used for the control unit to transmit the information to the storage unit, and a second communication line used for the control unit to receive the information to the storage unit,
the terminal member includes a first terminal member connected to the first communication line and a second terminal member connected to the second communication line,
the abutting member short-circuits the second terminal member and the first terminal member when in contact with the terminal member,
The image forming apparatus according to claim 9 , wherein the control unit determines whether the opening/closing member is in the open state or the closed state based on a signal input via the second communication line. The image forming apparatus according to claim 14, characterized in that the control unit outputs a predetermined signal from the first communication line when determining whether the opening/closing member is in the open state or the closed state based on a signal input via the second communication line. The image forming apparatus according to any one of claims 9 to 15, characterized in that, when the control unit determines that the opening/closing member is in the open state, the control unit transmits a signal to the memory unit via the communication unit, and determines whether the refill container is attached to the refill port depending on whether or not there is a response signal from the memory unit.

Images