JP3249695B2 - Image recording device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply control device such as a printer using an electrophotographic process and an image recording apparatus using the same.

[0002]

2. Description of the Related Art Conventionally, in a printer device or the like, a power supply is turned on / off by turning a switch provided on an AC power supply line on / off. In such an apparatus, the power switch is usually kept turned on or turned on / off once a day at the start and end of the work.

[0003]

However, even though the power is kept on, the printing time occupying the power-on time is very small, and most of the printing time is in the standby state. As described above, even when the printer is not used, power is supplied to most circuits of the apparatus, and there is a problem that wasteful power is consumed.

[0004] The present invention has been made in view of the above-described conventional example, and can greatly reduce power consumption other than during printing, improve operability, and can cope with power-off in an emergency. It is another object of the present invention to provide a power supply control device capable of ensuring the operability and turning on / off a power supply of an optional device in conjunction with the device main body, and an image recording apparatus using the same.

It is another object of the present invention to provide a power supply control device capable of using a switch having a small current capacity as a switch for turning off the AC power supply to a main power supply, thereby reducing the cost and an image recording apparatus using the same. I do.

[0006]

In order to achieve the above object, an image recording apparatus according to the present invention has the following arrangement. An image recording apparatus including a printer control unit, wherein first power supply means for supplying DC power to the printer control unit;
Power switch means including an electric circuit for turning on and off the supply of AC power to the first power supply means, reception monitoring means for monitoring reception of data from a higher-level device, and supply of DC power to the reception monitoring means A second power supply unit, a fixing unit including a heater to which AC power is supplied, a heater switch unit for turning on and off the supply of AC power to the heater, and a first power supply unit. A heater switch driving unit that is driven by a DC power supply and drives the heater switch unit. In a state where supply of DC power to the printer control unit is cut off by the power switch unit, data reception by the reception monitoring unit is performed. When the reception is monitored, the DC power is supplied from the first power supply unit to the printer control unit by switching on / off of the power switch unit. When the supply of AC power to the first power supply means is cut off by the power switch means, no DC power is supplied from the first power supply means to the heater switch driving means, whereby the heater switch is turned off. The means is cut off and the power supply to the heater is stopped. Preferably, there is further provided switch control means for outputting a switching signal for switching a switch state of the power switch means to the power switch means. Preferably,
The power switch means includes a relay driven by a switching signal output from the switch control means.
Preferably, the power switch means includes a rectifier circuit for rectifying AC power, a first switch means for switching supply of AC power to the rectifier circuit in accordance with a switching signal output from the switch control means, And a second switch for turning on and off the supply of AC power to the first power supply in accordance with the output of the rectifier circuit. Preferably, the power switch means has first and second switching means, and the first switching means is configured to switch the second switching means in response to a switching signal output from the switch control means.
The supply of AC power to the switching means is turned on and off, and the second switching means turns on and off the supply of AC power to the first power supply means according to the supplied AC power. Preferably, the apparatus further comprises detection means for detecting overheating of the heater, wherein the switch control means outputs a switching signal for turning off the power switch means when the detection means detects overheating of the heater. I do. Preferably, the apparatus further comprises means for detecting that image recording has not been performed for a predetermined time, wherein the switch control means switches the power switch means to an off state when it is detected that image recording has not been performed for a predetermined time. Output a signal. Preferably, a switching signal from the switch control means is output to the optional device as a remote signal for turning on / off the power of the optional device.

Alternatively, there is provided an image recording apparatus including a printer control unit, comprising a power supply unit for supplying DC power to the printer control unit, and an electric circuit for turning on and off the supply of AC power to the power supply unit. Power switch means, a fixing device including a heater to which AC power is supplied, a heater switch means for turning on and off the supply of AC power to the heater, and a DC power supply supplied by the power supply means;
Heater switch driving means for driving the heater switch means, and when the supply of AC power to the power supply means is cut off by the power switch means, DC power is supplied from the power supply means to the heater switch driving means. As a result, the heater switch is turned off, and the power supply to the heater is stopped.

[0008]

[0009]

【Example】

(Embodiment 1) FIG. 1 is a block diagram of a power supply and a power supply on / off control unit of a printer apparatus according to a first embodiment of the present invention.

In FIG. 1, reference numeral 5 denotes a noise filter,
A relay for turning on / off the supply of AC power, and a main power supply for supplying DC power to the printer. Reference numeral 2 denotes an auxiliary power supply, which remains on regardless of the operation of the relay 10. 3 is a DC output of the main power supply, and 4 is a DC output of the auxiliary power supply. Reference numeral 6 denotes a heater of the fixing device, and reference numeral 7 denotes a triac that controls on / off of the heater 6. Reference numeral 8 denotes an on / off signal for the heater 6, which controls the entire printer.
Are output under the control of the printer control unit 11 including Reference numeral 13 denotes a safety circuit unit that monitors the heater 6 of the fixing device so as not to run out of control, and monitors the power supply to the heater 6 by the current transformer 9. The safety circuit unit 13 sets the heater runaway signal 14 to a low level when the heater on / off signal 8 is off and the energization of the heater 6 is detected. Note that the heater runaway signal 14 is normally at a high level, and becomes high impedance when power is not supplied to the safety circuit 13. However, since the heater runaway signal 14 is pulled up by the auxiliary power supply, it becomes high level when the main power supply is off.

Reference numeral 11 denotes a printer control section centered on a CPU which controls the operation of the printer, and reference numeral 17 denotes an interface with a host (a personal computer or the like) that controls the printer.

The printer control unit 11 has an interface 1
If there is no print instruction for a predetermined time through 7, the shutdown signal 15 is set to the low level. This signal is normally at a high level, and enters a high impedance state when power is not supplied from the main power supply to the printer control unit 11. However, since the shutdown signal 15 is pulled up by the auxiliary power supply, it is at a high level when the main power supply is off.

Reference numeral 12 denotes an I / F monitoring unit which is always operated by an auxiliary power supply, monitors whether or not the interface 17 is accessed by a host, and outputs a wake-up signal 16. The wake-up signal 16 is always at a high level when the main power is on. When the main power is off, the wake-up signal 16 is at a low level while there is no access to the interface 17 from the host. Level.

Reference numeral 19 denotes a main power switch on the operation panel of the printer, and its on / off state, that is, the low level / high impedance of the signal 18 is determined by the priority unit 2.
Recognized as 0.

The priority unit 20 outputs a relay drive signal 21 based on the state of the switch 19 and a state signal 22 which is the logical product of the heater runaway signal 14, the shutdown signal 15, and the wakeup signal 16, and outputs a relay signal. 10 is turned on / off to turn on / off the main power. That is, usually
The status signal 22 is output as it is as the relay drive signal 21, but when the switch 19 is pressed, the status signal 2 is output.
2 is inverted and output as the relay drive signal 21. That is, by pressing the switch 19, the logic of the relay drive signal 21 can be preferentially changed.

The specific operation of the above configuration will be described. First, when the main power supply 1 is off, the heater runaway signal 14 and the shutdown signal 15 are at a high level, and the wake-up signal 16 is at a low level. Therefore, state signal 2
2 is a low level, which becomes the relay drive signal 21 as it is, the relay 10 is turned off, and the main power supply 1 remains off.

When the switch 19 is pressed, an inverted signal of the state signal 22 (low level) is transmitted to the relay drive signal 21.
And the relay 10 is turned on, and the main power supply 1 rises.

In addition, when the host accesses the I / F monitoring unit 12 through the I / F 17, the wake-up signal 16 goes high and the state signal 22 goes high, and the relay 10 is turned off. The power is turned on, and the main power supply 1 can be started.

When the main power supply 1 is on, when the safety circuit unit 13 detects a heater runaway, the heater runaway signal 14 goes low, the state signal 22 turns off, and the relay 1 goes off.
When 0 is turned off, the AC power supply to the main power supply 1 is cut off, and the power supply to the heater 6 is also cut off. Therefore, heating of the heater 6 can be prevented.

If the printing operation is not performed for a predetermined time, the printer control unit 11 sends a shutdown signal 1
Set 5 to low level. This also causes the relay 10 to turn off and the main power supply 1 to turn off.

Further, the main power can be turned off by pressing the switch 19.

FIG. 7 shows a switch 19, a wake-up signal 16, a shutdown signal 15, and a heater runaway signal 14.
The values of the relay drive signal 21 given by the respective states are shown. 0 indicates low level, 1 indicates high level,
Regarding the switch 19, 0 indicates a non-pressed state and 1 indicates a pressed state.

When the main power supply is off, both the shutdown signal 15 and the heater runaway signal 14 are at a high level, so that the possible states are limited to the inside of the frame 71. In a stable state after the power is turned off, the switch 19
Is not pressed, and the wake-up signal 16 is also at the low level, so that it is in the state of the circle 74. When the main power supply is turned on from this state, that is, when the signal 22 is set to a high level,
This can be done by either setting the wake-up signal to high level without pressing the switch 19 or pressing the switch 19 with the wake-up signal at low level. When the main power is turned on, the wake-up signal 1
6, the shutdown signal 15 and the heater runaway signal 14 are both at the high level and transit to the state of the circle 73.

When the main power supply is off, the wake-up signal 16 is at a high level, so that the possible states are limited to the inside of the frame 72. Here, the relay drive signal 22
It can be understood from FIG. 7 that the shutdown signal 15 or the heater runaway signal 14 is set to the low level or the switch 19 is pressed in order to set the switch to the low level.
When the main power supply is turned off, the state transits to the state of the circle 74.

The status signal 22 is used as a remote signal for turning on / off the power of another device. That is, if the signal is used as a signal for driving a relay for turning on and off the AC power of another device, the power can be turned off in synchronization with the printer device.

With the above-described configuration, only the part required for the activation of the main power supply by the auxiliary power supply is utilized, and the power consumption other than during printing can be significantly reduced. Also, priority is given to the on / off condition of the main power supply, and the switch operated by the operator is given first priority, thereby improving operability.
In addition, the power can be turned off in an emergency, and safety can be ensured. Further, by using the on / off signal of the main power supply as a remote signal for turning on / off the power of the optional device attached to the printer, the power of the optional device can be turned on / off in conjunction with the printer main body.

Here, the structure of the electrophotographic printer of this embodiment will be briefly described. FIG. 8 is a cross-sectional view showing the internal structure of a laser beam printer (hereinafter abbreviated as LBP) according to the present embodiment. The LBP can be input with character pattern data and the like and can be printed on recording paper.

In the figure, 740 is the LBP main body,
An image is formed on recording paper, which is a recording medium, based on the supplied character pattern and the like. Reference numeral 700 denotes an operation panel on which switches for operation, an LED display, and the like are arranged.
Is a printer control unit for controlling the entire LBP 740 and analyzing character pattern information and the like. The printer control unit 701 mainly converts character pattern information into a video signal and outputs the video signal to the laser driver 702. The printer control unit 701 includes many of the circuits shown in FIG.

The laser driver 702 is a semiconductor laser 70
And a laser beam emitted from the semiconductor laser 703 in accordance with an input video signal.
04 is turned on / off. The laser light 704 is swung right and left by a rotating polygon mirror 705 to scan on an electrostatic drum 706. Thus, an electrostatic latent image of a character pattern is formed on the electrostatic drum 706. This latent image is developed by a developing unit 707 around the electrostatic drum 706,
It is transferred to recording paper. A cut sheet is used as the recording paper. The cut sheet recording paper is stored in a paper cassette 708 mounted on the LBP 740, is taken into the apparatus by a paper feed roller 709 and transport rollers 710 and 711, and is supplied to the electrostatic drum 706. Is done.

The image developed on the recording paper by the developing unit 707 is supplied to a heater 71 in a fixing unit 711.
2 is fixed. The heater 712 corresponds to the heater 6 in FIG. (Embodiment 2) FIG. 2 shows a second embodiment, and the description of the same parts as in the first embodiment will be omitted.

In this embodiment, only the main power supply is cut off by the relay 10 directly from the AC power supply. The energization of the heater 6 is interrupted by the relay 30.

The relay 30 is driven by a relay drive unit 31. The relay drive unit 31 can be operated by power supply from the main power supply 1.
Turn 0 on / off. Therefore, when the power supply from the main power supply 1 is stopped, the relay driving section 31 becomes inoperable and the relay 3 becomes inoperable.
0 turns off.

Here, the condition under which the main power supply 1 is turned off, that is, the control of the relay drive signal 21 is the same as in the first embodiment. In addition, when the main power supply 1 is turned off, the relay drive unit 31 to which power is supplied from the main power supply 1 cannot operate, and the relay 30 is turned off to cut off the power supply to the heater 6.

In this embodiment, since the control of the main power supply 1 and the control of the heater 6 are made independent, even when the main power supply of the printer is turned on, for example, when printing is not performed for a predetermined time,
Before the main power supply 1 is turned off, it is also possible to control such that the heater 6 is first turned off and the apparatus stands by. (Embodiment 3) FIG. 6 shows the configuration of a printer according to a third embodiment, in which the switch circuit 40 shown in FIG. 3 is provided in place of the relay 10 in the first embodiment.

FIG. 3 shows the switch circuit 40 and the power supply unit, and the control unit and the like are omitted. In FIG. 3, the photo MOS relay 41 is turned on by the relay drive signal 21,
The AC-DC power supply 43 is turned on, thereby turning on the relay 42. By not directly driving the relay for turning on / off the AC power but directly driving the relay for turning on / off the power supply for driving the relay 42, the relay driving signal 21
Can be a very small current. (Embodiment 4) FIG. 4 shows a fourth embodiment, in which the switch circuit 50 of FIG. 4 is provided in place of the relay 10 in the first embodiment.

The photo MOS relay 51 is turned on by the relay drive signal 21, thereby turning on the AC relay 52 to turn on the main power supply 1. Also in this case, as in the third embodiment, the relay drive signal 21 can be made a very small current by not driving the relay for directly turning on and off the AC but driving the relay for turning it on and off. (Embodiment 5) FIG. 5 shows a fifth embodiment.
Is an AC line cut-off switch, and 61 and 62 are fuses. Reference numeral 30 denotes a relay for turning on / off the energization of the fixing heater, and a relay driving unit 31 which operates with a main power output.
And the relay 30 is turned off when the main power supply 1 is turned off. Therefore, when switch 60 is turned off, AC
Only the main power supply 1 cuts off the power supply to the heater 6.
Electricity can be cut off.

With the above configuration, a switch having a small current capacity can be used as the switch 60.

The present invention may be applied to a system constituted by a plurality of devices or to an apparatus constituted by a single device. Needless to say, the present invention can be applied to a case where the present invention is achieved by supplying a program to a system or an apparatus.

As described above, in the image recording apparatus according to the present invention, when the supply of AC power is cut off by the power switch means, no DC power is supplied to the heater switch driving means. The power supply to the heater can be stopped when the power is cut off. Thus, an alternating current flowing through the heater does not flow through the power switch means, and an effect that the current capacity can be reduced can be obtained.

[0039]

[0040]

[0041]

[0042]

[Brief description of the drawings]

FIG. 1 is a power supply control block diagram showing a first embodiment.

FIG. 2 is a power supply control block diagram showing a second embodiment.

FIG. 3 is a power supply control block diagram showing a third embodiment.

FIG. 4 is a power supply control block diagram showing a fourth embodiment.

FIG. 5 is a block diagram of a power supply control device according to a fifth embodiment.

FIG. 6 is a block diagram illustrating a configuration of a printer according to a third embodiment.

7 is a diagram showing a state of a relay drive signal 21. FIG.

FIG. 8 is a sectional view of the LBP.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main power supply 2 Auxiliary power supply 10 Relay 13 Safety circuit part 11 Printer control part 12 I / F monitoring part 20 Priority part

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-6-319003 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G06F 1/26 B41J 29/38 G03G 21 / 00 398 G06F 1/32 G06F 3/12

Claims (9)

(57) [Claims] 1. An image recording apparatus including a printer control unit, comprising: a first power supply unit for supplying DC power to the printer control unit; and a supply of AC power to the first power supply unit. Power switch means including an electric circuit to be turned off; reception monitoring means for monitoring reception of data from a host device; second power supply means for supplying DC power to the reception monitoring means ; and AC power supply. A fixing device including a heater, and a heater switch for turning on / off the supply of AC power to the heater.
And a DC power supply supplied by the first power supply means.
Heater switch for driving the heater switch means.
Switch driving means, and when reception of data is monitored by the reception monitoring means while supply of DC power to the printer control unit is interrupted by the power switch means, the power supply switch means is turned on. to perform the supply of DC power from the first power supply means by switching a switching to the printer control unit, by said power switch means to said first power supply means
When the supply of AC power is cut off, the first power supply means
No DC power is supplied to the heater switch driving means.
Before the heater switch is turned off.
The image recording apparatus according to claim Rukoto to stop power supply to the serial heater. 2. The image recording apparatus according to claim 1 , further comprising switch control means for outputting a switching signal for switching a switch state of said power switch means to said power switch means. 3. An image recording apparatus according to claim 2 , wherein said power switch means includes a relay driven by a switching signal output from said switch control means. 4. The power switch means comprises: a rectifier circuit for rectifying an AC power supply; and a first switch means for switching the supply of the AC power to the rectifier circuit in accordance with a switching signal output from the switch control means. 3. The image recording apparatus according to claim 2 , further comprising: a second switch for turning on / off the supply of AC power to the first power supply in response to an output of the rectifier circuit. 5. The power switch means comprises first and second power switches.
A switching means, said first switching means is Nyusetsu the supply of AC power to the second switching means in response to the switching signal outputted from said switch control means, said second switching means supplying 3. The image recording apparatus according to claim 2 , wherein the supply of the AC power to the first power supply unit is turned on / off according to the AC power to be supplied. 6. A switch signal for detecting overheating of the heater, wherein the switch control means switches the power switch means to an off state when the detection means detects overheating of the heater. The image recording apparatus according to any one of claims 2 to 5 , wherein the image recording apparatus outputs the image data. 7. The apparatus further comprises means for detecting that image recording has not been performed for a predetermined time, wherein the switch control means turns off the power switch means when it is detected that there is no image recording for a predetermined time. 2 through claim and outputs a switching signal to
7. The image recording apparatus according to any one of 6 . 8. The image according to claim 2 , wherein a switching signal from said switch control means is output to said optional device as a remote signal for turning on / off the power of the optional device. Recording device. 9. An image recording apparatus including a printer control unit, comprising: a power supply unit that supplies DC power to the printer control unit; and an electric circuit that switches on and off the supply of AC power to the power supply unit. Power switch means, a fixing device including a heater to which AC power is supplied, a heater switch means for turning on / off the supply of AC power to the heater, and a DC power supply supplied by the power supply means, Heater switch driving means for driving the heater switch means, and when the supply of AC power to the power supply means is cut off by the power switch means, no DC power is supplied from the power supply means to the heater switch driving means. Thus, the heater switch means is turned off to stop the power supply to the heater.