JP2001158123A - Led control apparatus and image-forming apparatus with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an LED control apparatus which can reduce wires to be arranged of a harness in a simple constitution when an LED substrate and a control substrate are connected by the harness. SOLUTION: At the substrate 100 of a panel part, one terminal of a switch 101 is connected to a source line connected to anodes of LEDs 110-113, and the other terminal of the switch 101 is connected to an output terminal 119. At the substrate of a printing control part 96, an input terminal 126 and a port SW of an ASIC 130 are directly connected with each other, which is pull- down connected by an R5. At the ASIC 130, a judgment logic to a switch input is set to a positive logic (high active). A connecting line of the harness 120 for the switch 101 can be an L6 alone, and a connecting line to be connected from the source line of the switch 101 to the port SW of the ASIC 130 is saved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an LED control device in which an LED board on which an LED and a switch are mounted, and a control board for controlling lighting of the LED in response to depression of the switch are connected by wiring. And an image forming apparatus provided with the LED control device.

[0002]

2. Description of the Related Art In a conventional image forming apparatus such as a printer, a panel substrate provided with LEDs, switches,
In this configuration, a substrate of a print control unit including an SIC and a memory is connected by a harness.

In such a configuration, when a switch on the panel substrate is pressed, a signal indicating this pressing is input to the ASIC on the substrate of the print control unit via the harness. The ASIC outputs a signal to turn on the LED in response to the input, and this signal is supplied to the LED on the panel substrate via the harness, and a predetermined LED is turned on.

[0004]

Conventionally, however, the input terminal for the switch in the ASIC on the substrate of the print control unit is set to the low active logic, so that the input terminal for the switch in the ASIC is connected to the switch. Two connection lines, a connection line with the press detection terminal and a connection line with the other terminal of the switch and the ground, have been required.

As a result, the harness includes a power supply line for supplying an anode of the LED, a signal line connected to the cathode of the LED, a line for detecting press-down connected to one terminal of the switch, It is necessary to be configured with a ground wire connected to the other terminal, and there is a problem that the wiring of the harness is increased by an amount required for the switch.

[0006] The present invention solves the above problems, and
When the ED board and the control board are connected with a harness,
An object of the present invention is to provide an LED control device and an image forming apparatus capable of reducing wiring of a harness with a simple configuration.

[0007]

According to a first aspect of the present invention, there is provided an LED control apparatus comprising: an LED board provided with an LED and a switch; and a control unit for controlling lighting of the LED. An LED control device connected to the control board by wiring means,
D has an anode connected to a power supply terminal, a cathode connected to an output terminal of the control means via the wiring means, and one end of the switch means connected to the L terminal.
The other end is connected to an input terminal of the control means via the wiring means while being connected to a common power supply terminal with the ED, and the input terminal is grounded via a resistor on the control board side. It is characterized by being.

According to the LED control device of the first aspect,
One end of the switch means is connected to a power terminal common to the LED, and the other end of the switch means is connected to the input terminal of the control means via the wiring means. Need only have a line connecting the one end of the switch means and the input terminal of the control means, and a line connecting the other end of the switch means and the input terminal of the control means. Since there is no need to provide, the number of connection lines can be reduced. When the LED board and the control board are connected by using such wiring means, when the switch means is in an open state, the input terminal of the control means is grounded via a resistor on the control board side. Input, a low voltage (Low) is input. When the switch is in a closed state, power supplied from the power terminal is applied to the resistor, and a voltage drop occurs in the resistor. Therefore, a high voltage (High) is input to the input terminal of the control means. In this way, by setting the logic of the input terminal of the control means in a manner opposite to the conventional one,
The number of connection lines in the wiring means is reduced.

According to a second aspect of the present invention, there is provided an LED control apparatus according to the first aspect, wherein a plurality of the LEDs are provided on the LED substrate. Are connected to a common power supply terminal, and each cathode side is connected to the corresponding output terminal of the control means via the wiring means.

[0010] According to the LED control device of the second aspect,
Since the plurality of LEDs on the LED board are connected on each anode side to a common power supply terminal and each cathode side is connected to the output terminal of the corresponding control means via the wiring means, respectively, Wiring from the power supply terminal can be used in common with the anode side of each LED and the one end side of the switch means, thereby reducing the number of connection lines in the wiring means.

According to a third aspect of the present invention, there is provided an LED control apparatus according to the first or second aspect, wherein the wiring means is a harness in which a plurality of wiring cables are integrally formed. It is characterized by the following.

[0012] According to the LED control device of the third aspect,
As the wiring means, a harness in which a plurality of wiring cables are integrally formed is used as the connection line, so that the wiring can be routed easily, and the number of wiring cables is reduced as described above, so that the routing is further facilitated. And the cost is reduced.

According to a fourth aspect of the present invention, there is provided an image forming apparatus comprising: an LED control device according to any one of the first to third aspects; and an image forming unit for forming an image on a recording material. It is characterized by having.

According to a fourth aspect of the present invention, the image forming apparatus includes an image forming unit for forming an image on a recording material and the LED control device according to any one of the first to third aspects. The cost and the size of the device can be reduced by reducing the size and the size of the substrate.

[0015]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. The following description is an embodiment in which the present invention is applied to a printer as an example of an image forming apparatus. First, an outline of the printer according to the present embodiment will be described.

(Outline of Printer) FIG. 1 is a sectional view showing a schematic configuration of a laser beam printer 1 as an image forming apparatus to which the present invention is applied. In FIG. 1, the laser beam printer 1 includes a feeder unit for feeding paper (not shown) at the bottom of a main body case 2. The feeder unit includes a paper pressing plate 10 that is pressed by a spring (not shown), a paper feeding roller 11, and a friction separating member 14. The uppermost sheet is separated between the feed roller 11 and the friction separating member 14 by the rotation of the roller, and the sheet is supplied at a predetermined timing.

A pair of registration rollers 12 and 13 are rotatably supported on the downstream side in the sheet conveyance direction by the rotation of the paper supply roller 11 rotating in the direction of the arrow in FIG. The sheet is conveyed to a transfer position formed by the transfer roller 21 at a predetermined timing.

The photosensitive drum 20 is made of a positively chargeable material, for example, an organic photoreceptor mainly composed of positively chargeable polycarbonate. More specifically, the photosensitive drum 20 has, for example, a cylindrical aluminum sleeve as a main body, and has a predetermined thickness (for example, about 20 μm) in which a photoconductive resin is dispersed in polycarbonate on an outer peripheral portion thereof. It is composed of a hollow drum on which a conductive layer is formed, and is rotatably supported by the main body case 2 with the cylindrical sleeve grounded. Further, the photosensitive drum 20 is driven to rotate in a direction indicated by an arrow by driving means (not shown).

The charger 30 is, for example, a scorotron type charger for positive charging that generates corona discharge from a charging wire made of tungsten or the like.

The laser scanner unit 40 includes a laser generator (not shown) for generating a laser beam L for forming an electrostatic latent image on the photosensitive drum 20, and a polygon mirror (pentahedral mirror) 41 driven to rotate. , A pair of lenses 42 and 4
5 and reflection mirrors 43, 44 and 46.

In the developing device cartridge 50, a toner accommodating chamber 52 is formed in a case 51. In the toner accommodating chamber 52, an agitator 53, a cleaning member 54, and a light shielding member 80 provided therebetween are rotated. It is rotatably provided around a shaft 55. The toner accommodating chamber 52 accommodates a positively chargeable nonmagnetic one-component developer having electrical insulation. Further, the toner storage chamber 52
Light transmitting windows 56 are provided on the side walls located at both ends of the rotating shaft 55. Further, the toner storage chamber 52 is provided on the photosensitive drum 20 side of the toner storage chamber 52 with an opening A.
And a developing chamber 57 for performing development is formed, and the supply roller 58 and the developing roller 59 are rotatably pivotally supported. The toner on the developing roller 59 is regulated to a predetermined layer thickness by a thin plate-like elastic layer thickness regulating blade 64 and is used for development.

The transfer roller 21 is rotatably supported,
It is made of a conductive foamed elastic body made of silicone rubber or urethane rubber. The transfer roller 21 is configured to reliably transfer the toner image on the photosensitive drum 20 to the paper by the applied voltage.

The fixing unit 70 includes the registration roller 12
The heating roller 71 and the pressing roller 72 are provided on the further downstream side in the sheet conveyance direction from the sheet feeding roller 13 to the pressure contact portion between the photosensitive drum 20 and the transfer roller 21. The toner image transferred to the sheet is heated and pressed while being conveyed by the heating roller 71 and the pressing roller 72 and is fixed on the sheet.

A pair of paper transport rollers 73 and a paper discharge roller 74 for paper transport are provided on the downstream side in the transport direction of the fixing unit 70, respectively, and a paper output tray 75 is provided on the downstream side of the paper discharge roller 74. Have been.

The photosensitive drum 20, the transfer roller 21, the charger 30, and the developing unit cartridge 50 are
It is housed in a process cartridge 2a, and the process cartridge 2a is provided detachably with respect to the laser beam printer 1. Further, the developing device cartridge 50 is provided detachably with respect to the process cartridge 2a.

In the laser beam printer 1 of the present embodiment as described above, the surface of the photosensitive drum 20 is
When the laser beam L modulated according to image information is emitted from the laser scanner unit 40, an electrostatic latent image is formed on the surface of the photosensitive drum 20.
This electrostatic latent image is visualized with toner by the developing device cartridge 50, and the visible image formed on the photosensitive drum 20 is conveyed to the transfer position by the photosensitive drum 20.
At the transfer position, the paper is supplied via the paper feed roller 11 and the registration rollers 12 and 13, and the visible image is transferred to the paper by a transfer bias applied by the transfer roller 21. After the transfer, the photosensitive drum 20
The toner remaining on the developing chamber 5
Collected in 7.

Next, the sheet is conveyed to the fixing unit 70, and is nipped and conveyed by the heating roller 71 and the pressing roller 72 of the fixing unit 70. The visible image on the sheet is pressed and heated to be fixed on the sheet. You. Then, the sheet is discharged to the discharge tray 75 above the laser beam printer 1 by the pair of transport rollers 73 and the discharge rollers 74, and the image forming operation is completed.

(Configuration of Control Unit) Next, the configuration of the control unit in the laser beam printer 1 of the present embodiment will be described in detail.

FIG. 2 is a block diagram showing the configuration of the control unit. As shown in FIG. 2, the control unit includes a main control unit 90.
, A low-voltage power supply unit 93, a high-voltage power supply unit 95, and a print control unit 96.

The main control unit 90 includes a parallel interface connector 91 and a USB connector 92 for connection with a computer or the like, a CPU and a memory (not shown), and a connector P9 for connection with a low-voltage power supply unit 93 in the control unit. , A connector P4 for connection with the print control unit 96 in the control unit, and a connector P10 for connection with the laser element 105 of the laser unit 40. With such a configuration, the main control unit 90
Controls the operation of the entire control unit.

The low-voltage power supply unit 93 includes a power switch 94, a connector CN1 for connecting to the halogen lamp 102 of the fixing unit 70, a connector CN101 for connecting to a print control unit 96 in the control unit, and not shown. It has a low-voltage power supply circuit. The low-voltage power supply circuit is a CPU
Alternatively, 5V used as a power supply for a memory or the like, and DC
This is a circuit for generating 24 V used as a power supply for the motor 98, the solenoid 99, and the like.

The high-voltage power supply unit 95 includes a connector CN2 for connecting to a print control unit 96 in the control unit, and a high-voltage power supply circuit (not shown). The high-voltage power supply circuit is a circuit that generates a high voltage of 3 kV for generating a voltage supplied to the charger 30 and a voltage supplied to the photosensitive drum 20 and the developing roller 59.

The print controller 96 includes a connector P7 for connecting to a fan 97, a connector P8 for connecting to a DC motor 98, and a small motor 104 for rotating the polygon mirror 41 of the laser unit 40.
P12, solenoid 99 for connection with
P13 and switch 101 for connecting to
Connector P14 for connection with the panel unit 100 provided with the like, connectors P5 and P15 for connection with the low voltage power supply unit 93, connector P3 for connection with the main control unit 90, high voltage power supply unit 95, an ASIC (not shown in FIG. 4 as an ASIC 130), and the like. The DC motor 98 is a motor generally called a main motor, and is a rotation drive source for the photosensitive drum 20, the developing roller 59, the heating roller 71, the transfer roller 21, the transport roller 73, and the like. In other words, the print control unit 96 controls the rotation of the main roller body related to the image forming operation by controlling the DC motor 98. The print control unit 96 controls supply of a high-voltage power supply necessary for an image forming operation by using a high-voltage power supply unit 95. Further, the print control unit 96 includes a small motor 104 of the laser unit 40,
Drive control of the solenoid 99 and the fan 97, control of key input and display on the panel unit 100,
The temperature of the heating roller 72 is controlled based on the temperature detected by the thermistor 103.

The control section as described above is constructed by mounting circuit elements and the like on a printed board for each section, and is mounted on a board mounting section 150 provided at the lower portion of the printer 1 as shown in FIG. . For example, the substrate of the print control unit 96 is mounted on the front side of the substrate mounting unit 150. However, the substrate of the panel unit 100 connected to the substrate of the print control unit 96 is attached to the front surface of the printer 1 as shown in FIG. The connection between the substrate of the print control unit 96 and the substrate of the panel unit 100 is performed by a harness described below.

(Connection between the panel substrate and the print control substrate)
Next, the connection between the panel unit substrate and the print control unit substrate will be described in detail.

As shown in FIG. 4, on the substrate of the panel section 100, a light emitting color LED 110, a green LED 111, a red LED 112, a yellow LED 113, and a switch 101 as a switch means are provided.
And are provided.

The anodes of the LEDs 110 to 113 are all connected to the power supply terminal 114, and the LEDs 110 to 113
113 are input terminals 115 to 118, respectively.
Connected to

One end of the switch 101 is connected to each of the L
As with the anodes of the EDs 110 to 113, the power supply terminal 114
, And the other end is connected to the output terminal 119.

On the other hand, an ASIC 130 as control means is provided on the substrate of the print control unit 96.
C130 has a port LE for controlling LED lighting.
D1 to LED4 and a port SW for switch input are provided.

The ports LED1 to LED4 are connected to output terminals 122 to 125 via resistors R1 to R4, respectively. The power supply terminal 121 is connected to a 5V power supply. Further, the port SW is connected to an input terminal 126, and the input terminal 126 is connected to a resistor R as shown in FIG.
5 is grounded.

The board of the print control section 96 and the board of the panel section 100 are connected to the harness 12 as a wiring means.
Connected by 0. The harness 120 includes FIG.
As shown in FIG. 6, six connection lines L1 to L6 are provided. The connection line L1 is connected to the power supply terminal 1 on the substrate of the print control unit 96.
21 and the power supply terminal 114 of the substrate of the panel unit 100. The connection lines L2 to L5 are connected to the output terminals 122 to 125 of the substrate of the print control unit 96 and the panel unit 1
It is used to connect the input terminals 115 to 118 of the substrate No. 00. The connection line L6 is connected to the input terminal 126 of the substrate of the print control unit 96 and the output terminal 11 of the substrate of the panel unit 100.
9 is used to connect the terminal 9.

The input terminal 1 of the substrate of the print control unit 96
26 is pull-down connected by a resistor R5,
When the switch 101 is open (off), the ASIC
A low (L) level voltage is input to the port SW 130. On the other hand, when the switch 101 is in the closed (on) state, a high (H) level voltage is input to the port SW of the ASIC 130.

Therefore, in the ASIC 130, the AS
When the input voltage at the port SW of the IC 130 is at the high level, the switch 101 is determined to be in the on state, and the logic of the determination for the switch input is set to positive logic (high active), so that the on / off state of the switch 101 is appropriately determined Can be determined.

With such a configuration, the connection line of the harness 120 related to the switch input is connected to the switch 10.
Only the connection line L6 used for connection to the first ground side connection terminal may be used, and the connection line for connection to the power supply side connection terminal of the switch 101 can be omitted.

On the other hand, in the conventional apparatus, FIG.
As shown in FIG.
6 'is pull-up connected by a resistor R6,
When the switch 101 is open (off), the ASIC
A high (H) level voltage is input to the port SW 130. On the other hand, when the switch 101 is in the closed (on) state, a low (L) level voltage is input to the port SW of the ASIC 130.

Therefore, in the conventional ASIC 130, when the input voltage at the port SW of the ASIC 130 is at a low level, it is determined that the switch 101 is on, and the logic of the determination for the switch input is set to negative logic (low active). Thus, the on / off state of the switch 101 is determined.

As a result of such a configuration, the connection line of the harness 120 related to the switch input is
In addition to the connection line L6 used for connection to the power supply side connection terminal 1 as well as the connection line L7 for connection to the earth side connection terminal of the switch 101, the number of connection lines has increased.

The power supply terminals 119 and 126 and the ground terminals 119 ′ and 12 ′ for the switch 101 are provided on both the substrate of the print control unit 96 and the substrate of the panel unit 100.
6 ′ are required, and furthermore, it is necessary to route two patterns each for connection between these terminals and the switch 101 and connection of these terminals on the substrate of the print control unit 96. This increases the cost and hinders downsizing of the substrate.

On the other hand, according to the present invention, not only the number of connection lines of the harness 120 can be reduced as described above, but also the number of terminals and the pattern for the switch 101 on each board can be reduced. , Cost can be reduced. Further, the size of the substrate can be reduced.

Further, since the width of the harness is reduced by reducing the number of connection lines of the harness, the wiring of the harness in the printer 1 is further facilitated, and the connection operation is facilitated. It can also contribute to miniaturization.

In the above-described embodiment, a case has been described in which the present invention is applied to a laser beam printer as an example of an image forming apparatus. However, the present invention is also applicable to an image forming apparatus such as an ink jet printer, a facsimile, and a copy. Applicable.

In addition to the image forming apparatus, the present invention may be used for other devices using LEDs, for example, display devices.

In the above description, an example has been described in which the LED is turned on when the switch 101 is pressed. However, the LED is actually turned on depending on an operation state such as an error of the image forming apparatus or the like. I have.

The anode and cathode of the LED are
It does not need to be directly connected to the power terminal or output terminal,
For example, it may be configured to be connected to these terminals via a resistor or the like.

Further, a plurality of switches 101 may be provided.

As described above, the present invention has been described based on the embodiments. However, the present invention is not limited to the above embodiments, and various improvements and modifications can be made without departing from the spirit of the present invention. Can easily be inferred.

[0057]

According to the LED control apparatus of the first aspect, one end of the switch means is connected to the power supply terminal common to the LED, and the other end is connected to the input terminal of the control means via the wiring means. Since the input terminal is grounded via a resistor on the control board side, the wiring means only needs to include a line connecting the one end of the switch means and the input terminal of the control means. Since there is no need to provide a line connecting the other end and the input terminal of the control means,
The number of connection lines can be reduced. In this way, by setting the logic of the input terminal of the control means in a manner opposite to the conventional one, the number of connection lines in the wiring means can be reduced, and the cost can be reduced.

According to the LED control device of the second aspect,
Since each anode of the LED was connected to a common power supply terminal and each cathode was connected to the output terminal of the corresponding control means via the wiring means, the wiring from the power supply terminal on the LED board was connected to the anode of each LED. , Can be used in common with the one end of the switch means, and the number of connection lines in the wiring means can be reduced, thereby reducing costs.

According to the LED control device of the third aspect,
Since the wiring means is a harness in which a plurality of wiring cables are integrally formed, wiring can be easily routed, and the number of wiring cables can be reduced to reduce cost.

According to the image forming apparatus of the fourth aspect, the LED control apparatus of any one of the first to third aspects,
And an image forming unit for forming an image on a recording material,
The reduction in the number of connections and the size of the substrate can reduce the cost and the size of the device.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a schematic configuration of an image forming apparatus according to an embodiment of the present invention.

FIG. 2 is a block diagram illustrating a schematic configuration of a control unit in the image forming apparatus of FIG.

FIG. 3 is a diagram for explaining a position of a control unit substrate in the image forming apparatus of FIG. 1;

FIG. 4 is a diagram showing a detailed configuration of a substrate of a print control unit and a substrate of a panel unit and a harness connecting these substrates in the control unit of FIG. 2;

FIG. 5 is a diagram illustrating a detailed configuration of a substrate of a print control unit and a substrate of a panel unit, and a harness connecting these substrates in a control unit of a conventional apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Laser beam printer 96 Print control part 100 Panel part 101 Switch 110-113 LED 114 Power supply terminal 120 Harness 121 Output terminal 126 Input terminal 130 ASIC L1-L6 Connection line R1-R5 Resistance

Claims (4)

[Claims] 1. An LED having an LED and switch means.
An LE connected to an ED board and a control board provided with control means for controlling lighting of the LED by a wiring means
D control device, wherein the LED has an anode side connected to a power supply terminal, a cathode side connected to an output terminal of the control means via the wiring means, and one end of the switch means, the LED And the other end is connected to an input terminal of the control means via the wiring means, and the input terminal is grounded via a resistor on the control board side. An LED control device, characterized in that: 2. A plurality of LEDs are provided on the LED substrate, each anode side is connected to a common power supply terminal, and each cathode side is connected to the corresponding control unit via the wiring unit. The LED control device according to claim 1, wherein the LED control device is connected to an output terminal. 3. The LED control device according to claim 1, wherein the wiring means is a harness in which a plurality of wiring cables are integrally formed. 4. L according to claim 1, wherein
An image forming apparatus comprising: an ED control device; and an image forming unit that forms an image on a recording material.