JP2001318565A - Power supply device, image forming apparatus, and output voltage control method - Google Patents

Abstract

(57) [Problem] To provide a power supply device capable of reliably avoiding a situation in which circuit operation is unstable or being reset, stabilizing operation of a main body, and improving stability at very low cost. , An image forming apparatus, and an output voltage control method. SOLUTION: A power supply slow start unit 2130 of the image forming apparatus includes a DC / DC converter 3010 for converting an output voltage of a DC power supply unit 2120, and a DC / DC converter 3010.
FET3 which receives the output voltage of the power supply unit 2120 as an input
030, a transistor 3060 for controlling the operation of the FET 3030, a capacitor 3040 for controlling the output voltage of the FET 3030, and resistors 3020 and 3050.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply device, an image forming apparatus, and an output voltage control method, and more particularly to an image forming apparatus such as a copying machine or a printer for scanning a document and forming an image on a sheet material. More particularly, the present invention relates to a power supply device, an image forming apparatus, and an output voltage control method suitable for mounting on a computer.

[0002]

2. Description of the Related Art Hitherto, various power supply output circuits have been proposed for realizing a slow start when power is turned on.
A conventional power supply output circuit is disclosed in, for example,
The technology described in 43559 has been proposed. The technique disclosed in this publication realizes a slow start, first raises a supply voltage of a logic circuit when power is turned on, and then raises a voltage of a drive circuit system.

[0003]

However, the above-mentioned prior art has the following problems. That is, the power supply output circuit disclosed in the above publication is a so-called startup sequence control circuit that only realizes a slow start at the time of power-on, and after power-on, for example, a supply voltage of a certain block. There is a problem that it does not solve the case where a slow start is required every time at ON / OFF.

[0004] The problem to be solved by the present invention will be described below by taking a copying machine as an example. The configuration of a general copying machine and the operation of the scanning optical system will be described with reference to FIG. In FIG. 5, reference numeral 1000 denotes a copying machine (image forming apparatus) main body. Reference numeral 1001 denotes an automatic document feeder for feeding a document to an exposure position, and 1002 denotes a document table glass as document placing means. The sheet material 30 is the sheet cassette 15
On board. Reference numeral 300 denotes a pickup roller, which feeds out sheet materials stacked on the sheet feeding cassette 15. The sheet material 30 is separated into one sheet by the separation sheet feeding rollers 100 and 200, and is sent to the transport path 19.

[0005] The sheet material 30 has a plurality of transport rollers 114b, 1
14a, the sheet is conveyed to the registration roller 113, and when other conditions such as an optical system are prepared, the registration roller 113 is moved.
Works. The image formed on the photoconductor 101 is transferred to the transfer unit 1.
At 05, the sheet material 30 is transferred to the sheet material 30, separated by the separation unit 106 so that the sheet material 30 is not wound around the photosensitive drum 101, and sent to the transport belt 102. Sheet material 3
0 is carried to the fixing roller 103 and the pressure roller 104,
The image is fixed by the fixing roller 103 and the pressure roller 104. The sheet material 30 is directly discharged from the sheet discharge rollers 111 and 11.
It is discharged out of the machine by 2.

When a double-sided copying operation is performed, the sheet material 30 is sent to the double-sided conveyance unit 130 by the flapper 122 without being discharged out of the apparatus. When making multiple copies on one side, the sheet material 30 advances in the direction of arrow B as it is and is conveyed to the registration roller 113. In the case of double-sided copying, the sheet material 30 is fed in the direction of arrow A once, and then fed in the direction of arrow B by switchback, so that the sheet material 30 is inverted and similarly conveyed to the registration rollers 113.

The fixing roller 103 fixes the toner or the like on the sheet material 30 by heat melting the toner or the like.
The toner is not always fixed to the sheet material 30 and may adhere to the fixing roller 103 depending on the density of the document. Therefore, especially when the number of sheets to be passed increases, in a high-speed machine, a web is arranged at a place other than the sheet passing portion of the fixing roller 103, and a mechanism for cleaning the fixing roller 103 while winding up a predetermined amount is provided. Has been taken.

If a paper jam occurs during the above-described series of copying operations, the user can open and close the door of the copier in accordance with the indication specified by the operation unit according to the location of the paper jam. The jam processing is performed (hereinafter, the paper jam processing is referred to as a jam processing). In this case, the jams are roughly divided into four places. The first is a paper feeding section jam from the paper feeding cassette 15, the second is a vertical path conveyance section jam from the paper feeding to the photosensitive drum 101, and the third is a photosensitive body jam. Jam in horizontal transport section from drum 101 to fixing section, and 4
The second is the discharge jam where discharge occurs after fixing.

FIGS. 7 to 10 are external views of the copying machine main body, showing a state in which a door is opened during jam clearance. 201 is an openable front door, 202 is an openable right door, 203
Denotes a first-stage paper feed cassette; 204 denotes a second-stage paper feed cassette;
Is a three-stage paper feed cassette, and 206 is a fixing door that can be opened and closed. Reference numeral 212 denotes a fixing unit, which is the fixing roller 103 and the pressure roller 104 shown in FIG.
Is stored.

[0010] The first of the four roughly divided jams is a paper feed failure caused by the operation of the pickup roller 300, and as shown in FIG. An instruction (display) is issued to the operation unit to pull out the paper feed cassette 203 or the paper feed cassette 204, open the right door 202 of the vertical path unit, and perform the jam processing.

Second, after the paper is fed, the transport rollers 114b and 114 are provided in the vertical path transport section up to the photosensitive drum 101.
a is when the sheet material 30 cannot be conveyed at the predetermined speed, and the right door 202 of the vertical path portion is opened as shown in FIG.
An instruction (display) is issued to the operation unit to perform the jam processing.

Thirdly, during transfer from the photosensitive drum 101 to the sheet material 30 or after transfer, a conveyance failure to the fixing unit occurs, and as shown in FIG. Prompt (display). In addition, an instruction (display) is issued to the operation unit to open the right door 202 of the vertical path unit according to the detected location and perform the jam processing.

The fourth case is that the sheet is not ejected within a predetermined time after the fixing, and as shown in FIG.
A message appears on the operation panel as if to open 6.

These operations are performed when one copying operation is set. If the copying operation is performed on a plurality of sheets, not only the jammed paper but also the sheet material 30 may be used.
In order to be able to process the sheet material 30 at all of the positions where the sheet is detected, various combinations of jam processing are required, and a jam processing request message corresponding to the jam processing is output to the operation unit.

For the first, second and fourth jam processing,
The remaining sheet material 30 can be confirmed by opening and closing the paper cassette drawer and opening and closing the door, so that the jam can be easily removed. On the other hand, in the third jam processing, since it is usually the most complicated place in the copying machine main body, although it is not shown, even after the opening / closing instruction of the front door 201 in FIG. Several procedures are required, such as turning the knob. In particular, when the sheet material 30 is approaching the fixing unit, even if the processing operation is performed according to the third procedure, the processing cannot be performed, and the fourth processing procedure may be required, and the sheet material 30 may be torn, Various processing operations are required.

On the other hand, in recent copiers, in order to improve the jam clearing property, a configuration in which a fixing machine and / or a horizontal transport section or both of them are integrated and movable and can be pulled out is mainly used. FIG. 11 shows the above-mentioned movable type, in which the fixing device and the horizontal transport section are integrally movable and pulled out to the front.

For example, when the third jam occurs, if another conventional model is used, the user first opens the front door 201 and then places the hand into which the hand can be inserted by vertically moving the lever 205 or the like so that the jam can be cleared. Can be processed if there is jam paper in the position where it can be seen, but if the sheet material comes into contact with the fixing unit and engages the rollers of the fixing unit,
A complicated operation is required, such as turning the knob to push it downstream, and then proceeding to the fourth processing operation.

Further, when a plurality of copies are made, since the inside of the copying machine is dark to protect the photosensitive drum, the sheet material still remains upstream and downstream in addition to the processed sheet material. In some cases, the jam is overlooked despite the fact that the jam processing is completed, and the processing is required again after returning to the standby state.

In the above-described movable configuration, in a case where the fixing device and the horizontal transport unit are integrated, for example, when a jam occurs, the front door is opened, and the unit is pulled out. And the processing operation can be performed without overlooking the sheet material to be removed.

Further, in the above-mentioned other conventional machine, when the user opens the front door, the power supply unit is shut down, the power supply to the heater is stopped, the safety of the user is ensured, and the front door is opened. With a seal or the like showing details of the jam clearing method (on the back side of the front door), the user performs the jam clearing of the jam location displayed on the operation unit in accordance with the sticker illustrated. The control unit of the copying machine shifts to the stop state, all jam clearing work is completed, and finally the user closes the front door to determine the state of each detection signal, and if it is determined that there is no abnormality, Move to the return operation.

On the other hand, in the case of the above-mentioned integrated unit of the fixing machine and the horizontal transport section, since the jam processing is always performed by pulling out the unit, the inside of the fixing machine and the like is covered by a cover when the unit is inserted into the copying machine body. Safety can be ensured by being covered and not easily accessible. Therefore, even if the front door is opened, it is not always necessary to shut down the power supply unit, and the operation unit and the like are energized as they are,
The jam processing method and the like can be displayed.

However, since this is a movable unit and a considerable amount of current flows through the heater, if the contacts of the connector that energizes the heater are separated during energization of the heater, a leak will occur and the life of the connector will be shortened. Become. Therefore, when the fixing unit and the integrated unit of the horizontal transport unit are attached / detached (when the contacts of the connector are separated), the power supply to the heater must be cut off. Therefore, when the front door is opened, it is synchronized with the front door. The power supply to the heater is always turned off.

On the other hand, the current flowing to the sensor or the control board is a weak current, and there is no particular leakage. Therefore, no control for cutting off the current supply is performed. However, when a control board is provided on the unit side, a capacitive load such as a capacitor is connected between a power supply and GND that are normally supplied. At the moment when the capacitive load is connected, a large current flows for a short time. For this reason, the power supply and the GND are affected, and for example, there occurs a problem that the voltage instantaneously drops or the GND rises.

Although there is a mechanism in which a switch is cut off simply to prevent hot insertion and removal, if a capacitive load is connected between the power supply and the GND as described above, it may take a short time at that moment. Although there is a large current flowing,
As a result, the operation of the internal circuit becomes unstable, and in the worst case, the voltage becomes lower than the reset voltage, which leads to a situation where the reset is applied.

The present invention has been made in view of the above points, and it is possible to reliably avoid a situation in which the circuit operation is unstable or reset, stabilize the operation of the main body,
A power supply unit that can improve stability at very low cost,
It is an object to provide an image forming apparatus and an output voltage control method.

[0026]

According to a first aspect of the present invention, there is provided a power supply device for supplying an output voltage of a power supply output means to a power supply target. It has a voltage converting means for converting a voltage, a switch means for inputting an output voltage of the power supply output means, a control means for controlling an operation of the switch means, and a charge / discharge means for controlling an output voltage of the switch means. It is characterized by the following.

In order to achieve the above object, the invention according to claim 2 is characterized in that the switch means is a power MOS type field effect transistor.

In order to achieve the above object, the invention according to claim 3 is characterized in that the charging / discharging means comprises a capacitor and a resistor.

In order to achieve the above object, the invention according to claim 4 is characterized in that the control means causes the charging / discharging means to charge when the output voltage of the power supply output means becomes equal to or higher than a predetermined voltage. I do.

To achieve the above object, the invention according to claim 5 is characterized in that the power supply target is a paper transport unit that can be pulled out from the image forming apparatus main body.

According to a sixth aspect of the present invention, there is provided an image forming apparatus including a power supply device for supplying an output voltage of a power output unit to a power supply target.
The power supply device includes a transformer for converting an output voltage of the power output unit, a switch that receives an output voltage of the power output as an input, a control unit that controls an operation of the switch, and the switch. And charging / discharging means for controlling the output voltage.

In order to achieve the above object, the invention according to claim 7 is characterized in that the switch means of the power supply device is a power MOS field effect transistor.

In order to achieve the above object, the invention according to claim 8 is characterized in that the charging / discharging means of the power supply device comprises a capacitor and a resistor.

According to a ninth aspect of the present invention, in the power supply device, the control means charges the charging / discharging means when an output voltage of the power supply output means becomes a predetermined voltage or more. It is characterized by making it.

In order to achieve the above object, a tenth aspect of the present invention is characterized in that the power supply target is a sheet transport unit that can be pulled out of the image forming apparatus main body.

In order to achieve the above object, the invention according to claim 11 is an output voltage control method applied to a power supply device for supplying an output voltage of a power supply output means to a power supply target, wherein the power supply output means is provided. A transforming step of converting the output voltage of the power supply, a switch step of receiving the output voltage of the power supply output means as an input, and control means for controlling the operation of the switch step;
Charge / discharge means for controlling the output voltage of the switching step.

In order to achieve the above object, a twelfth aspect of the present invention is characterized in that, in the switching step, a switching operation is performed by switching means composed of a power MOS type field effect transistor.

In order to achieve the above object, a thirteenth aspect of the present invention is characterized in that in the charging / discharging step, a charging / discharging operation is performed by charging / discharging means composed of a capacitor and a resistor.

In order to achieve the above object, the invention according to claim 14 is characterized in that, in the control step, control is performed to charge the charging / discharging means when the output voltage of the power supply output means becomes equal to or higher than a predetermined voltage. It is characterized by.

In order to achieve the above object, the invention according to a fifteenth aspect is characterized in that the power supply target is a paper transport unit that can be pulled out from the image forming apparatus main body.

[0041]

Embodiments of the present invention will be described below in detail with reference to the drawings.

The image forming apparatus according to the embodiment of the present invention is effective for an apparatus having a transport unit which is provided in the image forming apparatus main body as described in the above conventional example so as to be able to be pulled out and transports a sheet material. Details will be described using an image forming apparatus (copier) as an example. The internal structure of the image forming apparatus according to the embodiment of the present invention is the same as that of FIG.

FIG. 1 is a block diagram showing a configuration of a power supply control system of the image forming apparatus according to the embodiment of the present invention.
The image forming apparatus according to the embodiment of the present invention includes an image forming apparatus main body 1000, a fixing and conveying unit 2160, a double-sided conveying unit 2170, and a front door open / close detection switch 2180. Further, the image forming apparatus main body 1000 includes a CPU 2
110, a DC power supply unit 2120, and a power supply slow start unit 2130.
60 includes an attachment / detachment detection unit 2150, and the double-sided conveyance unit 2170 includes an attachment / detachment detection unit 2140. 2 in the figure
190, 2200 are drawer connectors.

The above configuration will be described in detail. The image forming apparatus main body 1000 has the same structure as that of FIG. CPU2
Reference numeral 110 denotes a central processing unit that controls the entire image forming apparatus. DC power supply unit 2120 is 5V, 12
V, 24V or the like is supplied to the power supply slow start unit 2130 or the like. The power supply slow start unit 2130 slowly starts up 24 V supplied from the DC power supply unit 2120 and
60, supply to the double-sided transport unit 2170. The fixing conveyance unit 2160 and the double-sided conveyance unit 2170 are configured to be detachable (pullable out) from the image forming apparatus main body 1000.

The fixing / conveying unit 2160 includes a fixing unit for fixing a sheet material. Double-sided transport unit 21
Numeral 70 is provided with a path for reversing the sheet material on which single-sided copying has been completed at the time of double-sided copying without discharging the sheet material and transporting it again to the transfer unit. The attachment / detachment detection units 2150 and 2140 are respectively a fixing conveyance unit 2160 and a duplex conveyance unit 21.
70, and the attachment / detachment detection units 2150, 2140
CPU 2110 based on signals output from
Are the fixing conveyance unit 2160 and the double-sided conveyance unit 217
Recognize whether 0 is attached or detached.

The front door detection switch 2180 detects the open / closed state of the front door of the image forming apparatus main body 1000. The drawer connectors 2220 and 2190 are connected to the image forming apparatus main body 1.
000 is a connector for attaching and detaching the fixing and conveying unit 2160 and the duplex conveying unit 2170, respectively, as shown in FIG. With the structure of FIG. 3, the drawer connectors 2220 and 2190 become detachable.

FIG. 2 is a circuit diagram showing a configuration of a power supply slow start unit 2130 (power supply device for realizing slow start) of the image forming apparatus according to the embodiment of the present invention. The power supply slow start unit 2130 (power supply device for realizing slow start) according to the embodiment of the present invention includes a DC / DC converter 3010, a resistor 30
20, 3050, 3070, a power MOSFET (hereinafter, FET) 3030, a capacitor 3040, a transistor 3060, and zener diodes 3080, 3090.

The above configuration will be described in detail together with the operation.
The DC converter 3010 is connected to the drain of the FET 3030 and the resistor 3020.
Zener diodes 3080 and 3090 are connected between the gate and source of the FET 3030, and a resistor 3050 and a capacitor 3040 are connected to the gate of the FET 3030. Further, a resistor 30 is connected in parallel with the capacitor 3040.
70, the collector of the transistor 3060 is connected in series to the resistor 3050, and the transistor 3060
A resistor 3020 is connected between the collector 3030 and the resistor 3050, and the base of the transistor 3060 is connected to ON / OFF signal lines from the attachment / detachment detection units 2140 and 2150 in FIG.

The DC / DC converter 3010 boosts the voltage of 24 V supplied from the DC power supply unit 2120, applies a voltage to the gate of the subsequent FET 3030 via the resistor 3020, and drives the FET 3030. 24V
The S output is controlled by transistor 3060. The resistor 3050 is a resistor that limits the current when the transistor 3060 is turned on and protects the transistor 3060.

When the DC power supply unit 2120 (power supply output circuit) of the image forming apparatus main body 1000 starts up and 24 V is output to the DC / DC converter 3010 of the power supply slow start unit 2130, the DC / DC converter 3010 outputs 36 V. I do. The voltage at point A is OF
It is 0 V in the F state. Next, the transistor 3060
When the ON signal is input to the
FF, the voltage at point A becomes 36V, but the voltage at point B is the combined resistance of the resistors 3020 and 3050 and the capacitor 3
Due to the time constant of 040, the voltage gradually decreases.
As a result, the output of the FET 3030 slowly becomes 24 V
Stand up until.

On the other hand, the attachment / detachment detector 214 shown in FIG.
0, 2150, etc.
When an OFF signal is input to the transistor 60, the transistor 3060 is turned on, and the charged capacitor 3040 is discharged via the resistors 3050 and 3070. At this time, a plurality of stabilizing capacitors (not shown) are usually connected to the 24VS line, and there is a difference in the discharge time between the gate and the source of the FET 3030, which may exceed the maximum rating. For this purpose, the Zener diode 308
0, 3090 are used to protect the applied voltage between the gate and the source of the FET 3030 so as to satisfy the maximum rating.

FIG. 4 shows a voltage / current waveform that is slowly started in the image forming apparatus according to the embodiment of the present invention. FIG. 6 shows voltage / current waveforms of an image forming apparatus according to a conventional example.

The correspondence between the claims of the present invention and the embodiments of the present invention is as follows. The power output means corresponds to the DC power supply unit 2120, and the transformer means is D
The switch means corresponds to the power MOSFET 3030, the control means corresponds to the transistor 3060, and the charge / discharge means corresponds to the capacitor 3.
040 and resistors 3020 and 3050.

As described above, according to the image forming apparatus of the embodiment of the present invention, the fixing and conveying unit 216
0, a power supply slow start unit 2130 that supplies power to the duplex conveying unit 2170, a DC / DC converter 3010 that converts the output voltage of the DC power supply unit 2120, and an FET 3030 that receives the output voltage of the DC power supply unit 2120 as an input. A transistor 3060 for controlling the operation of the FET 3030 and a capacitor 304 as a charge / discharge circuit for controlling the output voltage of the FET 3030
0, resistors 3020 and 3050, and when the output voltage of the DC power supply unit 2120 becomes equal to or higher than a predetermined voltage,
Since the control for charging the charge / discharge circuit including the capacitor 3040 and the resistors 3020 and 3050 is performed, the following effects are obtained.

When the control board is provided on the side of the unit (fixing transport unit 2160, double-sided transport unit 2170) that can be pulled out from the image forming apparatus main body 1000, after the capacity load is securely connected between the power supply and GND, In addition, since a predetermined voltage can be output in a certain time, current is supplied without causing a large current, and the situation of unstable circuit operation or resetting as in the past is reliably avoided. However, the operation of the image forming apparatus main body can be stabilized, and since the slow start is realized by the capacitor 3040 connected to the gate of the FET 3030, the stability can be improved at very low cost. It has the effect of being able to.

[Other Embodiments] (1) In the above-described embodiment of the present invention, a case where a copying machine is used as an image forming apparatus has been described as an example, but application of the present invention is limited to a copying machine. Instead, the present invention can be applied to a printer.

(2) In the above-described embodiment of the present invention, the case of the electrophotographic method is described as an example of the image forming method of the image forming apparatus. However, the application of the present invention is limited to the electrophotographic method. Not an inkjet system,
The present invention can be applied to a thermal transfer method, a heat-sensitive method, an electrostatic method, a discharge breakdown method, and the like.

(3) In the above-described embodiment of the present invention, the case of the image forming apparatus alone has been described as an example.
The application of the present invention is not limited to a single image forming apparatus, but may be applied to a system in which the image forming apparatus of the present invention and an information processing apparatus are connected by a network or the like.

[0059]

As described above, according to the power supply device according to the first to fifth aspects, the transformer means for converting the output voltage of the power supply output means and the switch means having the output voltage of the power supply output means as an input. And control means for controlling the operation of the switch means, and charge / discharge means for controlling the output voltage of the switch means, wherein the control means controls the charge / discharge means when the output voltage of the power supply output means is equal to or higher than a predetermined voltage. When a control board is provided on the side of the paper transport unit that can be pulled out from the image forming apparatus main body to perform charging control, a power supply-GND
Since a predetermined voltage can be output after a certain period of time after the capacitive load is securely connected in between, current is supplied without causing a large current, and the conventional circuit operation is not performed. Stability and resetting can be reliably avoided, the operation of the image forming apparatus main body can be stabilized, and a slow start is provided by a capacitor connected to the gate of the switch means (power MOS type field effect transistor). Since it is realized, there is an effect that the stability can be improved at very low cost.

According to the image forming apparatus of the present invention, since the power supply device is mounted on the image forming apparatus, the circuit operation becomes unstable or reset as in the prior art, similarly to the above. Thus, the operation of the image forming apparatus main body can be stabilized and the stability can be improved at very low cost.

According to the output voltage control method of the present invention, the output voltage control method is executed by the power supply device, so that the circuit operation becomes unstable or reset as in the prior art. Can be reliably avoided, and the operation of the image forming apparatus main body can be stabilized,
There is an effect that the stability can be improved very inexpensively.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a power supply control system of an image forming apparatus according to an embodiment of the present invention.

FIG. 2 is a circuit diagram showing a configuration of a power supply slow start unit of a power supply control system of the image forming apparatus according to the embodiment of the present invention.

FIG. 3 is a perspective view showing the appearance of a drawer connector for electrically connecting and coupling the main body of the image forming apparatus, the fixing and conveyance unit, and the double-sided conveyance unit according to the embodiment of the present invention.

FIG. 4 is an explanatory diagram showing voltage / current waveforms when a slow start is performed in the image forming apparatus according to the embodiment of the present invention.

FIG. 5 is a configuration diagram illustrating an internal structure of an image forming apparatus according to an embodiment of the present invention and a conventional example.

FIG. 6 is an explanatory diagram showing voltage / current waveforms when a slow start is performed in an image forming apparatus according to a conventional example.

FIG. 7 is a perspective view illustrating a state in which a door is opened at the time of jam clearance of an image forming apparatus according to a conventional example.

FIG. 8 is a perspective view illustrating a state in which a door is opened at the time of jam clearance of an image forming apparatus according to a conventional example.

FIG. 9 is a perspective view showing a state in which a door is opened at the time of jam clearance of an image forming apparatus according to a conventional example.

FIG. 10 is a perspective view showing a state in which a door is opened at the time of jam clearance of an image forming apparatus according to a conventional example.

FIG. 11 is a perspective view showing a state in which a door is opened at the time of jam clearance of an image forming apparatus according to a conventional example.

[Explanation of symbols]

 2110 CPU 2120 DC power supply unit 2130 Power supply slow start unit 2160 Fixing transport unit 2170 Double-side transport unit 3010 DC / DC converter 3020, 3050, 3070 Resistance 3030 Power MOSFET 3040 Capacitor 3060 Transistor 3080, 3090 Zener diode

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H02J 1/00 310 G06F 1/00 330G F-term (Reference) 2H027 EJ17 ZA01 5B011 DB02 DB12 DB21 EB08 JA21 MB01 MB06 5G065 BA00 BA04 DA07 EA01 FA02 GA06 GA07 HA07 HA16 JA02 KA02 KA09 LA01 MA10 NA01 NA02 NA05 5H410 BB04 CC02 DD02 DD05 EA11 EA37 EB37 KK02 5H430 BB01 BB09 BB11 CC02 EE06 KK02 KK06 KK07

Claims (15)

[Claims] 1. A power supply device for supplying an output voltage of a power supply output means to a power supply target, comprising: a transformer for converting an output voltage of the power supply output means; and an output voltage of the power supply output means. A power supply device comprising: a switch unit; a control unit that controls an operation of the switch unit; and a charge / discharge unit that controls an output voltage of the switch unit. 2. The power supply according to claim 1, wherein said switch means is a power MOS field effect transistor. 3. The power supply device according to claim 1, wherein said charging / discharging means comprises a capacitor and a resistor. 4. The power supply device according to claim 1, wherein said control means causes said charging / discharging means to charge when an output voltage of said power output means becomes equal to or higher than a predetermined voltage. 5. The power supply device according to claim 1, wherein the power supply target is a paper transport unit that can be pulled out of the image forming apparatus main body. 6. An image forming apparatus equipped with a power supply device for supplying an output voltage of a power supply output device to a power supply target, wherein the power supply device converts the output voltage of the power supply output device. An image, comprising: switch means for inputting an output voltage of the power supply output means, control means for controlling the operation of the switch means, and charge / discharge means for controlling the output voltage of the switch means. Forming equipment. 7. An image forming apparatus according to claim 6, wherein said switch means of said power supply device is a power MOS type field effect transistor. 8. The charging / discharging means of the power supply device,
7. The image forming apparatus according to claim 6, comprising a capacitor and a resistor. 9. The image forming apparatus according to claim 6, wherein said control means of said power supply device charges said charging / discharging means when an output voltage of said power output means becomes equal to or higher than a predetermined voltage. apparatus. 10. The image forming apparatus according to claim 6, wherein the power supply target is a sheet transport unit that can be pulled out of the image forming apparatus main body. 11. A method for controlling an output voltage applied to a power supply device for supplying an output voltage of a power supply output means to a power supply target, comprising: a transforming step of converting an output voltage of the power supply output means; An output voltage control method, comprising: a switching step for inputting an output voltage of the means, a control means for controlling an operation of the switching step, and a charging / discharging means for controlling an output voltage of the switching step. 12. The power MOS in the switching step.
12. The output voltage control method according to claim 11, wherein a switching operation is performed by a switching means constituted by a field effect transistor. 13. The output voltage control method according to claim 11, wherein in the charging / discharging step, charging / discharging operation is performed by charging / discharging means including a capacitor and a resistor. 14. The control step of controlling the charging / discharging means to charge when the output voltage of the power supply output means becomes equal to or higher than a predetermined voltage.
The described output voltage control method. 15. The output voltage control method according to claim 11, wherein the power supply target is a sheet transport unit that can be pulled out of the image forming apparatus main body.