JP3495478B2 - Image forming device - Google Patents

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 having an input / output control means for controlling the operation of the apparatus via a CPU and a bus line.

[0002]

2. Description of the Related Art In recent years, in controlling image forming apparatuses,
It is common to use a microcomputer to control the operation of the device. Also, regarding the abnormality detection of the apparatus, there is an invention of performing automatic failure diagnosis by checking the drive circuit controlled by the microcomputer in the inactive state and the simulated operating state.
-161558 is disclosed. The automatic failure diagnosis includes the operation 1 for checking the inoperability of the device by the detection of the self-diagnosis start signal, the operation 2 for sending the operation signal to the device when the inoperability is confirmed, and the operation for checking the operation. Three
The above three operations are performed, and when an abnormality is detected in the operation 1 or the operation 3, it is also performed by a routine for determining an abnormality.

[0003]

However, what is carried out by such automatic failure diagnosis is to check the inoperative state of only a single load and the simulated operating state, and there are many limits on the load and timing to be detected. There are restrictions. Further, in general, the control unit for controlling the entire apparatus and the signal input / output unit for inputting / outputting control detection signals of the load system of each means, sensors, etc., are often independent board configurations. . In many cases, the control unit handles high-speed signals with a high operating frequency, and is installed shielded in the device due to noise resistance, radiation noise, and the like. In addition, the signal input / output unit is arranged near the load of each means and the sensor in many cases in order to handle the load of each means, the control detection signal of the sensor, etc., due to the relation of components and harnesses and their distribution. Become. Therefore, if the connection and contact between the signal lines of the control unit and the signal input / output unit are incomplete, there is a problem that the operation and safety of the device are impaired.

The present invention is intended to solve the above-mentioned problems of the prior art, in which the load of each means from the signal input / output unit is
Mainly detects the connection and contact of each parallel port connected to the load that controls driving, heat source on / off, etc., and the connection state is complete or incomplete regardless of whether the device is in standby or in operation. It is an object of the present invention to provide an image forming apparatus capable of confirming the above.

[0005]

To achieve this object, the present invention provides a control means for controlling the entire apparatus, an optical writing means for forming a latent image on a photoconductor by a laser optical system, and a photoconductor. A developing unit that visualizes the latent image on the surface with toner; a transfer fixing unit that transfers and fixes the visualized image on a sheet;
In an image forming apparatus provided with a drive unit for moving a sheet and a drive unit of each unit, a bus interface connected to the control unit by a bus line for transmitting and receiving a control signal,
Data registers of at least two, which can be arbitrarily set for input and output and hold a control signal, and a register for inputting and outputting a control signal between the register and each means.
A signal input / output unit having a plurality of input / output ports corresponding to input / output ports, registers are set for input / output, and the output ports of the output registers are connected via signal lines. > Arbitrarily selected second output port different from the first output port for outputting the control signal to the constant means, and the input register corresponding to the same data bit position as the first output port
It connects the input port of the plurality of input ports, a control hand
By changing the data input according to the data output from the stage
It is characterized by confirming the connection and contact of multiple I / O ports of the register .

Further, in the image forming apparatus, a bus interface connected to the control means by a bus line for exchanging control signals and at least two or more input / output settings can be arbitrarily set and control signals can be held. And a signal input / output unit having a plurality of input / output ports corresponding to the data bits of the register for inputting / outputting control signals to / from the unit and each unit, and setting the register for input / output to output. Register for multiple output ports
An arbitrarily selected second output port different from the first output port for outputting a control signal from the inside to a predetermined means via a signal line, and an input corresponding to the same data bit position as the first output port. Connect to the input port among the multiple input ports of the register for data , and connect the device according to the data output from the control means.
Multiple I / O ports of register by converting data input
It is characterized in that the connection and contact are confirmed and each address setting of the output register and the input register is a combination of "0" and "1" inverted.

Further, in the image forming apparatus, a bus interface which is connected to the control means by a bus line for exchanging control signals, and at least two or more input / output settings can be arbitrarily set and control signals can be held. And a signal input / output unit having a plurality of input / output ports corresponding to the data bits of the register for inputting / outputting control signals to / from the unit and each unit, and setting the register for input / output to output. Register for multiple output ports
Different data bit locations and a second output port selected in another optional from the first output port for outputting a control signal to a predetermined unit, and the first output port via the signal line from being
Connects the input port of the plurality of input ports of the input register that, data corresponding to data output from the control means
Depending on the change of input, the connection of multiple I / O ports of the register
The feature is that the contact is confirmed .

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram showing a schematic configuration of an image forming apparatus according to an embodiment of the present invention. In FIG. 1, 1 is a control unit for controlling the entire apparatus, 2 is an optical writing unit for forming a latent image on a photoconductor by a laser optical system, and 3 is a developing unit for visualizing the latent image on the photoconductor with toner. Reference numeral 4 is a transfer fixing unit for transferring and fixing the visualized image on a sheet, 5 is a driving unit for moving a driving unit of the sheet and each unit, and 6 is connected to the control unit 1 by a bus line to exchange control signals. , A signal input / output unit that holds the control signal and inputs / outputs a control signal to / from the load / sensor of each unit.

The control unit 1 is generally a CPU, ROM, RA
It is composed of M, and other modules are timer, DMA (Direct Memory Access), PWM (Pulse
Width Modulation), ADC (Analog Digital Converte
r), DAC (Digital Analog Converter), USAR
T (Universal Synchronous Asynchronous Receiver-Tran
In some cases, a smitter), interrupt controller, peripheral interface, etc. are added.

The signal input / output unit 6 for exchanging signals with the control unit 1 is composed of a parallel input / output register (hereinafter referred to as a parallel port) to which a plurality of input / output ports are connected, and as another module, a timer. , PWM,
In some cases, ADC, DAC, USART, interrupt controller, peripheral interface, etc. are added. A control signal is sent from the control unit 1 through the signal input / output unit 6 to each load.
The control unit 1 controls the operation of the device by inputting the device status signal from the sensor provided in each unit to the control unit 1 through the reverse path.

FIG. 2 shows the connection between the address lines, data lines and bus lines of the control line of the control unit and the signal input / output unit, and the signal line of the signal input / output unit and each unit and the signal lines of the sensors in the embodiment. FIG. 3 is a block diagram showing a signal line of the control unit and the signal input / output unit, a bus line of the control line, the load input / output unit and the load system of each unit, and a signal line of sensors in the embodiment. It is a block diagram showing a connection with. Figure 3
In the figure, 7 is a signal input / output section having address / data lines capable of multiplexing (time division processing). The difference between FIG. 2 and FIG. 3 is that the address line and the data line of the signal input / output unit 6 for exchanging signals with the control unit 1 are the address / data lines capable of multiplexing (time division processing). That is what I did.

Further, FIG. 4 is a diagram showing a connection example of an output port and an input port as setting of the parallel port of the signal input / output unit 6 in the first embodiment of the present invention. In FIG. 4, the parallel port PC is a parallel port for output,
Set the parallel port PF as the input parallel port,
A connection example of the port 0 (PC0) of the parallel port PC and the port 7 (PF7) of the parallel port PF is shown.

[0013]

[Table 1]

First, the parallel port of the signal input / output unit 6 will be described. According to the information obtained from the bus interface, in the addresses A3 to A0 shown in (Table 1), the areas A3 to A0: 1000 to 1111 indicate the addresses of the input / output direction setting registers of the parallel ports PA to PF, and the data D7. It is possible to set input / output parallel ports of the parallel ports PA to PF in units of each bit indicated by D0 to D0. "1" for parallel port for input,
When set to "0", the output parallel port is set. As a result, the output and input of the parallel port can be arbitrarily set, and the signal input / output unit 6 can be connected in a versatile manner. However, the interface level of the parallel port differs depending on the layout of the device and the distance between the boards.

In the first embodiment, the parallel port PA
~ PD is set to the output parallel port and D7 ~ D
0: all "0", PE and PF are set as input parallel ports, and D7 to D0: all "1".

[0016]

[Table 2]

In the port 7 (D7) of the parallel port PC which is temporarily set as the output parallel port, the "*" mark shown in (Table 2) is connected to the load for controlling the drive / on / off output of the heat source. If so, one arbitrary port is selected from the remaining ports of the parallel port PC, and the port 7 (D7) of the parallel port PF set as the input parallel port is shown in (Table 2). It will be connected to the "◎" mark.

The CPU of the control unit 1 outputs data for controlling the load connected to the port 7 (D7) of the parallel port PC according to the operating specifications. At that time, the data bit corresponding to an arbitrary port of the parallel port PC connected to the port 7 (D7) of the parallel port PF is rewritten so as to be "0" or "1" at an arbitrary timing. In the first embodiment, the port of the parallel port PC is port 0 (PC0). After that, parallel port P
Input the data of F and confirm that the port 7 (D7) of the parallel port PF is "0" or "1".

If the change of the input port is synchronized with the rewriting of the output port, the parallel port PC of the address (0010) is normally connected, and the arbitrarily selected port 0 ( The two input / output ports of D0) and the port 7 (D7) of the parallel port PF are also normally connected (see FIG. 4). That is, the port 7 (D7) of the parallel port PF is normally connected.

Poor contact with the connection connector or connection harness,
If there is a wire break, the changes in "0" and "1" are not synchronized,
An abnormality can be detected on the control unit 1 side. If a load connected to an output port with a parallel output port and being controlled is repeatedly turned on / off, that output port is set as an input parallel port without using another output port. You may connect to the input port.

From the above, another output port different from the load control output port of the output parallel port is connected to the input port, and the data output including the data bit for connection confirmation is input from the input parallel port to the data input. By confirming the change in the data bit, the connection can be confirmed even in the operating state of the device without setting a special device state for confirming the connection. In particular, by making the data bits of the output port and the input port connected to the control load requiring monitoring particularly the same, the control unit 1 can check the connection state including the data line.

FIG. 5 is a diagram showing a connection example of an output port and an input port as setting of the parallel port of the signal input / output unit in the second embodiment of the present invention. In FIG.
The parallel ports PC and PD are set as output parallel ports, the parallel ports PF and PE are set as input parallel ports, and the port 0 and parallel port P of the parallel port PC are set.
The connection example of the port 7 of F, the port 1 of parallel port PD, and the port 6 of parallel port PE is shown.

[0023]

[Table 3]

Similar to the first embodiment, the port 7 (D
In 7), a load whose driving / on / off output of the heat source is controlled is connected to the “*” mark shown in (Table 3), and the port 6 (D6) of the parallel port PD is also shown in (Table 3). If a load whose driving and heat source on / off outputs are controlled is connected to the "*" mark, one of the parallel port PC and PD ports is set as the input parallel port. It will be connected to the port 7 (D7) of the parallel port PF and the "⊚" mark (see (Table 3)) of the port 6 (D6) of the parallel port PE.

In the combination of the input / output parallel ports described above, the addresses A2 to A0 are the addresses obtained by inverting "0" and "1", and the parallel port PC (010), the parallel port PF (101), and the parallel port A combination of the port PD (011) and the parallel port PE (100) is used. This allows
When the address line is defective, it is possible to prevent the same address designation when only one bit of the address line is designated differently.

The CPU of the control unit 1 outputs data for controlling the load connected to the port 7 (D7) of the parallel port PC in accordance with the operating specifications. At this time, the port 7 of the parallel port PF ( The data bit corresponding to an arbitrary port of the parallel port PC connected to D7) is rewritten to be "0" or "1" at an arbitrary timing. Similarly, data output for controlling the load connected to the port 6 (D6) of the parallel port PD is performed, and any port of the parallel port PD connected to the port 6 (D6) of the parallel port PE is output. The data bit corresponding to is rewritten to be "0" or "1" at an arbitrary timing. In the second embodiment, the port of the parallel port PC is port 0 (PC0), the parallel port PD
Becomes port 1 (PD1).

After that, data is input to the parallel ports PF and PE, and the port 7 (D7) of the parallel port PF,
It is confirmed that the port 6 (D6) of the parallel port PE becomes "0" and "1". If these changes in the input port are synchronized with the rewriting of the output port, the address (0010,001)
This means that the control unit 1 normally outputs the address of each parallel port from the output parallel port of 1) to the input parallel port of the address (0101, 0100). That is, for the addresses A2 to A0, "0" and "1" are normally output from the control unit 1, and A3 is used as the address of the parallel port PA to PF input / output direction setting register. Therefore, it can be seen that it is normal because the input parallel port and the output parallel port can be set.

From the above, by setting the address of the combination of the input parallel port and the output parallel port, the change in the data bit of the data output and the data input can be surely confirmed even in a plurality of combinations. The address line connection can be confirmed.

FIG. 6 is a diagram showing a connection example of an output port and an input port as setting of the parallel port of the signal input / output unit in the third embodiment of the present invention. In FIG.
The parallel port PC is set as the output parallel port and the parallel port PF is set as the input parallel port, and an example of connection between the port 0 (PC0) of the parallel port PC and the port 6 (PF6) of the parallel port PF is shown.

In the same manner as in the first embodiment, a load whose driving / on / off output of a heat source is controlled is connected to the port 7 (PC7) of the parallel port PC to control the connected load. , The data bit corresponding to the arbitrarily selected port 0 (PC0) of the parallel port PC is set to "0" at any timing.
Rewrite it to be "1". After that, data input to the parallel port PF is performed. At this time, the first embodiment
Is that the port 0 of the parallel port PC is connected to an arbitrary port of the parallel port PF, not the port 7 of the parallel port PF corresponding to the port 7 to which the load of the parallel port PC is connected. In the third embodiment, the connection with the port 6 of the parallel port PF is confirmed to be "0" and "1". This confirms that the output and input parallel ports are properly connected.

Further, if the input / output ports are open collectors, open drains, etc., the respective input / output ports can be directly connected. For example, the port 0 of the parallel port PC for output, the port 1 of the parallel port PD, and the port 5 of the parallel port PE for input are connected. In the data output of the address (0010) to the parallel port PC, the change of the data bit of the port 0 between “0” and “1” is synchronized with the data input of the parallel port PE of the address (0100) and the data bit of the port 5 is synchronized. After confirming the change of "0" and "1", the connection between the parallel port PC and the parallel port PE is confirmed. Similarly, the change of "0" and "1" in synchronization with the change of "0" and "1" of the port 1 of the parallel port PD of the address (0011) and the port 5 of the parallel port PE of the address (0100). By doing this, the connection between the parallel port PD and the parallel port PE is confirmed.

As described above, if the relationship between the output data bit and the input data bit for each address is defined, a plurality of output parallel ports can be provided for the input parallel port, and connection confirmation can be performed. Cost increase can be suppressed. Further, the defective parallel port can be determined from the confirmation result of each data input obtained from the input parallel port connected to the plurality of output parallel ports.

FIG . 7 is a diagram showing an example of connection of input / output ports of a signal input / output unit capable of multiplexing (time division processing) address lines and data lines of bus lines. In FIG. 7, the output port and the input port of the signal input / output unit 7 are connected, and after the control and confirmation data output to the output parallel port, the input parallel port data is input.
The fact that confirmation is performed by changing the input port in synchronization with the change of the output port is the same as in each of the above-described embodiments.

Output and input ports not used for control may be connected, and a diode for preventing backflow from the input port may be provided between the connected output port and the input port. As soon as the control unit 1 can confirm the abnormality by the above configuration, the safety of the device is improved by shifting from the normal operation to the fail-safe operation for ensuring the safety, and the defective portion can be identified when the device is repaired. Can also be used.

[0035]

As described above, according to the present invention,
To the output port of the output parallel port of the signal input / output unit,
When a load whose drive / heat source ON / OFF output is controlled is connected, by connecting an output port other than that output port and an input parallel port input port, data bits other than control data bits Can be confirmed, and the connection can be confirmed even in the operating state of the device.
Furthermore, by making the data bit positions of the output port and the input port to which the load is connected the same, it is possible to check the connection of the control load that requires monitoring, especially in the data line between the control unit and the signal input / output unit. Become.

If the address line is broken, the normal address line is pulled up or terminated.
The address line is fixed to either "0" or "1". By defining the address of the combination of the input / output parallel port so that "0" and "1" are inverted, and confirming the change of the data bit of the data output and the data input, the connection state of the address line is surely confirmed. I can confirm. Further, in the case of a configuration in which time division processing (multiplex) is performed on the address line and the data line, the connection can be confirmed by using the same line for the data line.

By connecting a plurality of output ports to the input port and defining the relationship between the output data bit and the input data bit for each address, the connection can be confirmed with a slight increase in cost. Further, a defective parallel port can also be discriminated from each confirmation result of the input parallel port connected to the plurality of output parallel ports.

From the above, even if a connection or contact failure occurs, the control section can detect the connection or contact failure of the device and prevent an erroneous operation.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of an image forming apparatus according to an embodiment of the present invention.

FIG. 2 is a bus line of address lines, data lines, and control lines of the control unit and the signal input / output unit according to the embodiment of the present invention;
FIG. 3 is a block diagram showing connections between a signal input / output unit, a load of each unit, and a signal line of a sensor.

FIG. 3 is a block diagram showing connections between address / data lines of a control unit and a signal input / output unit, a bus line of a control line, a signal input / output unit and loads of each unit, and a signal line of a sensor according to an embodiment of the present invention. It is a figure.

FIG. 4 is a diagram showing a connection example of an output parallel port and an input parallel port as setting of a parallel port of a signal input / output unit according to the first embodiment of the present invention.

FIG. 5 is a diagram showing a connection example of arbitrary bits of an arbitrary output parallel port and an arbitrary input parallel port as setting of a parallel port of a signal input / output unit according to the second embodiment of the present invention.

FIG. 6 is a diagram showing a connection example of an output parallel port and an input parallel port as setting of a parallel port of a signal input / output unit in Embodiment 3 of the present invention.

FIG. 7 is a diagram showing a connection example of input / output ports of a signal input / output unit capable of multiplexing (time division processing) an address line and a data line.

[Explanation of symbols]

1 ... Control part, 2 ... Optical writing part, 3 ... Developing part, 4 ... Transfer fixing part, 5 ... Driving part, 6, 7 ... Signal input / output part.

─────────────────────────────────────────────────── ─── Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) B41J 2/44 G06F 3/00 H04N 1/00 106

Claims (3)

(57) [Claims] 1. A control unit for controlling the entire apparatus, an optical writing unit for forming a latent image on a photosensitive member by a laser optical system, and a developing unit for developing the latent image on the photosensitive member with toner.
An image forming apparatus comprising a transfer fixing <br/> means for fixing transferred images obtained by the sensible Zoka the paper, and a driving <br/> means for moving the driving part of the paper and each of the units, the control A bus interface connected to the means by a bus line for exchanging control signals, a register consisting of at least two or more and capable of arbitrarily setting input and output, and holding the control signal, the register and each of the means data of the register for inputting and outputting of the control signal and
A signal input / output unit having a plurality of input / output ports corresponding to bits, and setting the register for input / output,
Via the signal line from the multiple output ports of the output register
A second output port selected in another optional from the first output port for outputting said control signal to a predetermined unit by, the input register corresponding to the same data bit position and said first output port Data corresponding to the data output from the control means by connecting with an input port among a plurality of input ports
Multiple I / O ports of the register depending on input changes
An image forming apparatus characterized by confirming connection and contact of . 2. A control means for controlling the entire apparatus, an optical writing means for forming a latent image on a photoconductor by a laser optical system, and a developing means for developing the latent image on the photoconductor with toner.
An image forming apparatus comprising a transfer fixing <br/> means for fixing transferred images obtained by the sensible Zoka the paper, and a driving <br/> means for moving the driving part of the paper and each of the units, the control A bus interface connected to the means by a bus line for exchanging control signals, a register consisting of at least two or more and capable of arbitrarily setting input and output, and holding the control signal, the register and each of the means data of the register for inputting and outputting of the control signal and
A signal input / output unit having a plurality of input / output ports corresponding to bits, and setting the register for input / output,
Via the signal line from the multiple output ports of the output register
A second output port selected in another optional from the first output port for outputting said control signal to a predetermined unit by, the input register corresponding to the same data bit position and said first output port Data corresponding to the data output from the control means by connecting with an input port among a plurality of input ports
Multiple I / O ports of the register depending on input changes
Of the output register and the input register are set to “0”,
An image forming apparatus characterized in that a combination of "1" is reversed. 3. A control unit for controlling the entire apparatus, an optical writing unit for forming a latent image on a photosensitive member by a laser optical system, and a developing unit for developing the latent image on the photosensitive member with toner.
An image forming apparatus comprising a transfer fixing <br/> means for fixing transferred images obtained by the sensible Zoka the paper, and a driving <br/> means for moving the driving part of the paper and each of the units, the control A bus interface connected to the means by a bus line for exchanging control signals, a register consisting of at least two or more and capable of arbitrarily setting input and output, and holding the control signal, the register and each of the means data of the register for inputting and outputting of the control signal and
A signal input / output unit having a plurality of input / output ports corresponding to bits, and setting the register for input / output,
Via the signal line from the multiple output ports of the output register
First and second output ports selected to another optional and the output port, a plurality of said first input register data bit locations is different from the output port for outputting the control signal to the predetermined unit and Connect with the input port of the input port of
Data input according to the data output from the control means
Of the input / output ports of the register
An image forming apparatus characterized by continuously checking contact .