JP3746387B2 - Image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image forming apparatus that is also called a digital multifunction peripheral in which optional devices such as a fax controller and a printer controller are combined with a digital copying machine, and more particularly to termination of signals output from the fax controller, printer controller, and the like. The present invention relates to an image forming apparatus characterized by processing.
[0002]
[Prior art]
In recent years, so-called digital multifunction peripherals that include an image reading apparatus and combine a FAX function and a printer function with a copy function for copying a read original have been widely used. In such a digital multi-function peripheral, the number of signal lines is inevitably increased because a plurality of functions are mounted on a single machine. With this type of machine termination processing, power consumption increases as the number of signal lines increases. Increased.
[0003]
In order to reduce the power consumption of the termination processing unit, there is a method of separating the termination processing unit and the power supply line. For example, Japanese Patent Application Laid-Open No. 10-268992 discloses that a voltage is used to separate the termination processing unit and the power supply line. Circuit elements such as means for comparison, exclusive OR, and transistors are necessary.
[0004]
[Problems to be solved by the invention]
Thus, conventionally, since the power consumption increases, if the termination processing unit and the power supply line are separated in order to reduce the power consumption, the circuit element is required, resulting in an increase in the cost of the device.
[0005]
The present invention has been made in view of such a point, and an object thereof is to provide an image forming apparatus capable of reducing power consumption without causing an increase in cost.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the first means includes an image forming means, and in the image forming apparatus that forms an image by connecting an optional device having another function, the first means supplies power to the optional device. and a second power supply line, said second line for returning the image forming apparatus main body side power supplied from the optional device by the power supply line, the first and the terminating resistor connected to the line, A second terminal resistor connected to the first terminal resistor, a signal line for outputting a signal from the option device to the image forming apparatus main body, and the option device based on the output signal. and control means for turning on said first power supply line, is connected to the signal line connection point between the second terminating resistor and the first termination resistor is output from said optional device It is characterized in.
[0007]
According to a second means, in the first means, the first power supply line is a power supply line that is turned off in the energy saving mode, and the second power supply line is a power supply line that is not turned off even in the energy saving mode. Features.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[0011]
FIG. 1 is a block diagram showing a system configuration of an image forming apparatus according to an embodiment of the present invention. This system includes a digital copying machine 1 and a FAX controller 1000 connected to the digital copying machine 1 as an option. The digital copying machine 1 further basically includes an operation unit 100, an ADF 200, a scanner / IPU 300, a printer unit 400, a main control unit 600, a bank unit 700, a PSU 800, and a bus switch unit 900.
[0012]
The operation unit 100 includes a print start key for instructing start of image formation, a numeric keypad used for setting the number of copies, functions provided for connected optional devices, in this case, an apparatus function setting key for setting FAX transmission, A liquid crystal touch panel and the like for displaying set functions and data are provided.
[0013]
The ADF 200 includes sensors for detecting the size of the set document, transmits the detected document size data to the main control unit 600, and sets the set document at a predetermined timing according to a command from the main control unit 600. Digitally feeds a document onto a contact glass provided on the upper surface of the digital copying machine, and discharges the document from the contact glass after scanning.
[0014]
A scanner / IPU (Image Processing Unit) 300 irradiates an original set on a contact glass with illumination light from an illumination lamp, and reflects reflected light from the original through a reading optical system such as a mirror group, a filter, and a lens. The image formed on the CCD, the signal photoelectrically converted by the CCD is amplified, and A / D converted to obtain digital image data. This digital image data is subjected to processing such as predetermined shading correction and gamma correction, and image processing suitable for visualization with toner is performed. Further, if there is designation of scaling processing, processing processing, etc. from the operation unit 100, these processings are also executed, and the digital image data subjected to image processing at a predetermined timing is sent to the bus switch unit 900.
[0015]
The printer unit 400 performs gamma conversion or the like for matching the digital image data sent from the bus switch unit 900 to the characteristics specific to the printer, and charges the electrostatic latent image based on this by driving a laser diode (LD). Formed on the photoconductor. The electrostatic latent image formed on the photoconductor is visualized with toner by a developing unit, transferred to a sheet fed from the bank unit 700, and melted and fixed by a fixing unit to form a visible image. The paper is discharged out of the machine.
[0016]
The main control unit 600 sets the ADF 200, the scanner / IPU 300, the printer unit 400, the bus switch unit 900, and the FAX controller 1000 in accordance with functions set from the operation unit 100 or the like. In addition, a document feed timing is transmitted to the ADF 200 or a scanner start signal is transmitted to the scanner / IPU 300 by a start signal sent from the operation unit 100 or a polygon motor synchronization signal sent from the printer unit 400. It controls the entire digital copying machine including image forming process control such as fixing toner increase on paper and discharging paper.
[0017]
The bank unit 700 feeds paper to the printer unit 400 in response to a control signal from the main control unit 600.
[0018]
A PSU (Power Supply Unit) 800 connects a power line 5V that is turned off and a power line 5VE that is not turned off to an optional device, in this case, the FAX controller 1000, and supplies power to the optional device by a control signal from the main control unit 600. To do. Further, the power lines 5VE and 25V that are not turned off are supplied to the entire digital copying machine 1.
[0019]
The bus switch unit 900 performs path switching of image data according to a control signal from the main control unit 600. For example, at the time of copying, an image data path is set from the scanner / IPU 300 to the printer unit 400, and at the time of FAX transmission, an image data path is set from the scanner / IPU 300 to the FAX controller 1000. An image data path is set in the printer unit 400.
[0020]
The FAX controller 1000 converts the digital image data AWKD [7: 0] sent from the bus switch unit 900 into a FAX specification in accordance with serial communication TXD and RXD with the main control unit 600 and is connected to a telephone line. The image data transmitted to another FAX or the image data transmitted from the other FAX is converted into the interface specification ARKD [7: 0] with the digital copying machine 1, and the digital image data is sent to the bus switch unit.
[0021]
FIG. 2 is a block diagram showing a connection state between the bus switch unit 900 and the FAX controller 1000. In the figure, the left side from the one-dot chain line shown in the center is the bus switch unit 900 and the right side is the FAX controller unit 1000.
[0022]
The bus switch unit 900 is provided with a driver 901, a receiver 904, and a receiver 909, and the FAX controller 1000 is provided with a receiver 1005, a driver 1006, and a driver 1007.
[0023]
The driver 901 transmits the serial communication transmission signal TXD from the main control unit 600 and the image data AWKD [7: 0] from the scanner / IPU 300 to the FAX controller 1000 side, and receives them by the receiver 1005 on the FAX controller 1000 side. The driver 901 can set the output to high impedance by a control signal from the main control unit 600. Here, the image data AWKD [7: 0] is composed of eight buses, but is represented by one line in FIG. The driver 901 is connected to the power supply line 5VE that is not turned off, and is driven by the power supply line 5VE.
[0024]
The receiver 904 receives a signal WKUP transmitted from the driver 1006 of the FAX controller 1000 to the main control unit 600 in order to turn on the power supply line 5V that is turned off from the FAX controller 1000. This signal WKUP is received by the receiver 904 through termination resistors 902 and 903 connected to the power supply 5VE that is not turned off. The driver 1006 is connected to the non-off power source 5VE from the PSU 800, and the non-off power source 5VE supplied to the driver 1006 is also supplied to the terminal resistors 902 and 903 of the bus switch unit 900 when the FAX controller 1000 is connected to the bus switch unit 900. The power supply 5VE that is connected and does not turn off is received from the FAX controller 1000 side.
[0025]
The receiver 909 is supplied with the power supply 5VE that is not turned off, and receives image data ARKD [7: 0] from the driver 1007 of the FAX controller 1000. The image data ARKD [7: 0] is transmitted from the driver 1007 via the termination resistors 905, 906, 907, and 908 connected to the power supply line 5V that is turned off when the FAX controller 1000 is connected. Here, the image data ARKD [7: 0] is composed of eight buses, but is represented by one line as in the case described above.
[0026]
On the FAX controller 1000 side, the serial communication transmission signal TXD from the main control unit 600 and the image data AWKD [7: 0] from the scanner / IPU 300 are terminated with the terminating resistors 1001, 1002, 1003 connected to the power supply line 5V to be turned off. Received by the receiver 1005 via 1004. A signal WKUP transmitted from the FAX controller 1000 to the main control unit 600 is transmitted by a driver 1006 connected to the power supply 5VE that is not turned off. The serial communication reception signal RDX of the main control unit 600 and the image data ARKD [7: 0] to be transmitted to the printer unit 400 are transmitted by the driver 1007 connected to the power supply line 5V to be turned off.
[0027]
The PSU 800 supplies power lines to the bus switch unit 900 and the FAX controller side through the power line 5VE that is not turned off and the power line 5V that is turned off. The driver 901, the receiver 904, the receiver 909 of the bus switch unit 900 and the driver 1006 of the FAX controller 1000 are connected to the power supply line 5VE which is not turned off. The resistors 902 and 903 are also connected to the power supply line 5VE that does not turn off. The FAX controller receiver 1005, driver 1007, and termination resistors 1001, 1002, and 1003.1004 on the receiver 1005 side are connected to the power supply line 5V to be turned off. The terminating resistors 905, 906, 907, and 908 on the receiver 909 side are also connected to the power supply line 5V.
[0028]
With this configuration, when the FAX controller 1000 is not connected, the power supply lines 5V and 5VE are not supplied to the termination resistors 902, 903, 905, 906, 907, and 908 of the bus switch unit 900. There is no waste of power. Further, when the FAX controller 1000 is connected and when the FAX controller 1000 is not used, the main control unit 600 sets the output of the driver 901 of the bus switch unit 900 to high impedance and turns off the power supply line 5V to turn off the PSU 800. The power consumption in the FAX controller 1000 can be suppressed. At the same time, the power supply line 5V to be turned off is not supplied to the termination resistors 905, 906, 907, and 908 of the bus switch unit 900, and power is not wasted by these termination resistors.
[0029]
At this time, the FAX controller 1000 only performs monitoring by a part of ICs driven by the power supply line 5VE that does not turn off the reception signal from the telephone line. When the FAX controller 1000 detects a reception signal from the telephone line, the FAX controller 1000 activates a signal WKUP for turning on the power supply line 5V to the main control unit 600, and the main control unit 600 turns on the power supply line 5V of the PSU 800, Transition to image forming operation. When the operation unit 100 is operated so as to perform FAX transmission when the power supply line 5V to be turned off is turned on, a request for using the FAX controller 1000 is input from the operation unit 100 to the main control unit 600, and the main control unit 600 receives the PSU 800. Is turned on, the FAX transmission setting is transmitted to the FAX controller 1000, and a normal document reading operation is started. Note that the WKUP signal, RXD signal, and ARKD signal from the FAX controller 1000 side are respectively connected to the connection point between the termination resistors 902 and 903, the connection point between the termination resistors 905 and 906, and the connection point between the termination resistors 907 and 908. Since the signal lines of the TXD signal and the AWKD signal from the bus switch unit 800 side are connected to the connection point between the termination resistors 1001 and 1002 and the connection point between the termination resistors 1003 and 1004, these are connected. Signal reflection is reduced, and signal transmission speed can be increased.
[0030]
By configuring in this way, it is possible to reduce the power consumption of the digital termination processing unit of the signal output from the optional device even when the optional device is not connected or in an energy saving mode such as when not in use. .
[0031]
【The invention's effect】
As described above, according to the present invention, power consumption can be reduced without causing an increase in cost .
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating a schematic configuration of a digital multifunction peripheral according to an embodiment of the present invention.
2 is a circuit diagram showing a state of a connection part between a bus switch part and a FAX controller of the digital multi-function peripheral shown in FIG. 1;
[Explanation of symbols]
1 Digital MFP 5V Power line 5VE turned off Power line 100V not turned off Operation unit 200 ADF
300 scans / IPU
400 Printer unit 600 Main control unit 700 Bank unit 800 PSU
900 Bus switch unit 901 Driver 902, 903, 905, 906, 907, 908 Termination resistor 904, 909 Receiver 1000 FAX controller 1001, 1002, 1003, 1004 Termination resistor 1005 Receiver 1006, 1007 Driver

Claims (2)

In an image forming apparatus that has an image forming unit and connects an optional device having other functions to form an image,
First and second power supply line for supplying power to the optional device,
A line for returning the power supplied from the second power supply line from the optional device to the image forming apparatus main body;
A first termination resistor connected to the line;
A second termination resistor connected to the first termination resistor;
A signal line for outputting a signal from the optional device to the image forming apparatus main body,
Control means for turning on the first power line of the optional device based on the output signal;
With
An image forming apparatus, wherein a connection point between the first termination resistor and the second termination resistor is connected to the signal line output from the optional device. 2. The image forming apparatus according to claim 1, wherein the first power supply line is a power supply line that is turned off in the energy saving mode, and the second power supply line is a power supply line that is not turned off even in the energy saving mode .

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