Image forming device

Abstract

To prevent an electrolytic solution blown out from an electrolytic capacitor from being attached to electrical elements provided under the electrolytic capacitor in the vertical direction.SOLUTION: An image forming apparatus of the present invention has image forming means and a power supply unit, and a circuit board of the power supply unit is provided to intersect a horizontal plane. The power supply unit has an electrolytic capacitor, electrical elements, and a plate-like member that is provided between the electrolytic capacitor and the electrical elements in the vertical direction and includes a predetermined surface extending in a second direction intersecting the vertical direction. When seen along a component side of the circuit board, the plate-like member projects beyond a leading end of the electrolytic capacitor in a first direction. The plate-like member is formed with a notch or a hole. At least part of an area where the notch or the hole is provided is at a position separate from the component side of the circuit board compared with positions where the electrical elements are provided in the first direction.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to an image forming apparatus equipped with a power supply device having an electrolytic capacitor equipped with an explosion-proof valve. [Background technology]

[0002] Conventionally, image forming devices such as laser beam printers have used power supply devices that rectify and smooth commercial AC power to convert it into DC power. In such power supply devices, the rectified and smoothed DC power is input to a transformer and switched to obtain the desired output, and the power supply device has a rectifier circuit that rectifies the input AC power and a smoothing circuit that smooths the rectified current.

[0003] Smoothing circuits require large-capacity capacitors, so electrolytic capacitors are sometimes used. When excessive voltage is applied to an electrolytic capacitor, gas is generated from inside the capacitor. To prevent the gas from building up pressure inside the capacitor, electrolytic capacitors have a notch called an explosion-proof valve (also called a pressure valve). When this explosion-proof valve is activated, gas containing electrolyte is ejected from inside the capacitor to the outside. Because the ejected electrolyte is a conductive liquid, if it comes into contact with surrounding circuits, the circuits may be affected. Specifically, if the electrolyte comes into contact with the primary circuit, a short circuit may occur, causing a large current to flow.

[0004] In response to this, Patent Document 1 describes the provision of a deflector plate opposite the explosion-proof valve of the electrolytic capacitor, which guides the electrolyte sprayed out when the explosion-proof valve opens to an area of ​​the circuit where adhesion of the electrolyte is not a problem. Specifically, the deflector plate is configured to guide the sprayed electrolyte to the secondary circuit without adhering to the primary circuit. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 6598511 Summary of the Invention [Problem to be solved by the invention]

[0006] In Patent Document 1, a circuit board is incorporated into an image forming apparatus so that the mounting surface of the circuit board is oriented in a substantially vertical direction. The electrolytic capacitor mounted on the circuit board is configured to extend in a substantially horizontal direction. In this configuration, when the explosion-proof valve opens, the electrolytic solution spurts out in a substantially horizontal direction. The deflector plate located opposite the valve guides the electrolytic solution to the secondary circuit, but some of the electrolytic solution flows out vertically below the electrolytic capacitor.

[0007] In the configuration of Patent Document 1, the primary circuit is not provided vertically below the electrolytic capacitor, so the above-mentioned problems of short circuits do not occur. However, in order to achieve more flexible circuit layout, it is desirable to be able to reduce the impact of the electrolyte that is sprayed out when the explosion-proof valve is opened, even in a configuration in which an electric element is provided vertically below the electrolytic capacitor.

[0008] An object of the present invention is to prevent electrolytic solution ejected from an electrolytic capacitor from adhering to an electric element provided below the electrolytic capacitor in the vertical direction. [Means for solving the problem]

[0009] In order to achieve the above object, the present invention provides: an electrolytic capacitor extending in a first direction protruding from a mounting surface of the circuit board; an electric element provided below the electrolytic capacitor in the vertical direction and exposed from the mounting surface; and a plate-like member provided between the electrolytic capacitor and the electric element in the vertical direction and having a predetermined surface extending in a second direction intersecting the vertical direction when viewed in a direction perpendicular to the mounting surface of the circuit board; a notch or a hole formed in the plate-like member, and at least a part of an area where the notch or the hole is provided is located farther from the mounting surface of the circuit board in the first direction than a position where the electric element is provided. .

[0010] In order to achieve the above object, the present invention provides: an electrolytic capacitor extending in a first direction protruding from a mounting surface of the circuit board; an electric element provided below the electrolytic capacitor in the vertical direction and exposed from the mounting surface; and a plate-like member provided between the electrolytic capacitor and the electric element in the vertical direction and having a predetermined surface extending in a second direction intersecting the vertical direction when viewed in a direction perpendicular to the mounting surface of the circuit board; wherein the plate-like member protrudes beyond a tip end of the electrolytic capacitor in the first direction, and the plate-like member is inclined obliquely with respect to the mounting surface so that an end position of the plate-like member on the circuit board side in the first direction is positioned vertically higher than an end position of the plate-like member on the opposite side of the circuit board in the first direction. . [Effects of the Invention]

[0011] According to the present invention, it is possible to prevent the electrolyte solution ejected from the electrolytic capacitor from adhering to the electric element provided below the electrolytic capacitor in the vertical direction. [Brief explanation of the drawings]

[0012] [Figure 1] Overall schematic diagram of a laser beam printer [Figure 2] Power supply circuit block diagram [Figure 3] FIG. 1 is a diagram showing the layout of a power supply device in a laser beam printer. [Figure 4] FIG. 1 is a perspective view of a power supply device in which a notch is provided in a heat sink according to a first embodiment; [Figure 5] Cross-section of the power supply showing the electrolyte dropping from point C [Figure 6] Cross-section of the power supply showing the electrolyte dropping from point B [Figure 7] Front view of the power supply unit showing the heat sink tilted toward point B [Figure 8] Front view of the power supply unit showing the heat sink tilted toward point A [Figure 9] FIG. 1 is a perspective view of a power supply device in which a new notch is provided in a heat sink according to a first embodiment; [Figure 10] Front view of the power supply unit showing the heat sink tilted toward point A [Figure 11] Cross-section of the power supply showing the electrolyte dropping from point E [Figure 12] FIG. 1 is a perspective view of a power supply device having a hole in a heat sink according to a first embodiment; [Figure 13] 10 is a cross-sectional view of a power supply device equipped with an induction plate according to a second embodiment of the present invention; DETAILED DESCRIPTION OF THE INVENTION

[0013] Example 1 The following describes a case in which a power supply device 100 of the present invention is applied to an image forming apparatus. FIG. 1 shows an overall view of a laser beam printer 700 (hereinafter referred to as printer 700) as an example of an image forming apparatus. The printer 700 includes a photosensitive drum 701 as an image carrier on which an electrostatic latent image is formed, a charging unit 702 that uniformly charges the photosensitive drum 701, and a developing unit 703 that develops the electrostatic latent image formed on the photosensitive drum 701 with toner. The toner image developed on the photosensitive drum 701 is transferred in a transfer unit 705 to a sheet as a recording material supplied from a cassette 704. The toner image transferred to the sheet is then fixed in a fixing unit 706 heated by a heater 117. The sheet with the fixed toner image is discharged to a paper output tray 707. The printer 700 includes a power supply device 100, which supplies power to a driving unit such as a motor and a control unit 500. The control unit 500 controls the image forming operation, the sheet conveying operation, the temperature of the heater 117, and the like.

[0014] FIG. 2 is a circuit block diagram of a power supply device 100 according to a first embodiment. A flyback switching power supply will be described as an example. An AC voltage Vac is supplied to the power supply device 100 from a commercial power supply 101. The voltage Vac supplied to the power supply device 100 is then supplied to a diode bridge 104 via a fuse 102 and a filter circuit 103. The AC voltage Vac is rectified by the diode bridge 104 to form a pulsating waveform with one side positive. The pulsating waveform voltage is smoothed to approximately DC by the action of a primary electrolytic capacitor 105. The voltage across both ends of the primary electrolytic capacitor 105 is defined as Vdc, the potential at the positive terminal of the primary electrolytic capacitor 105 as DCH, and the potential at the negative terminal of the primary electrolytic capacitor 105 as DCL.

[0015] The smoothed voltage Vdc is input to a primary winding Np of a transformer 108 and fed back to the commercial power supply 101 via a FET 107 from the negative terminal of a primary electrolytic capacitor 105 and the diode bridge 104. The on / off timing of the FET 107 is controlled by a switching control unit 106. The power supply power required for the switching control unit 106 to operate is obtained from the ST terminal before switching starts, and from the VB-VS voltage generated from an auxiliary winding Nb of the transformer 108 after switching starts. VS of the switching control unit 106 is connected to DCL.

[0016] A rectifier 151 is connected to the secondary winding Ns of the transformer 108. The power converted into a voltage by the transformer 108 is supplied to the rectifier 151, where it is rectified and smoothed to become a DC voltage Vout. Vout is output to a load 152 external to the power supply device 100. The load 152 may be, for example, a CPU (not shown) provided in the control unit 500 of FIG. 1 or a drive unit such as a motor. Vout is connected to a voltage feedback unit 150, which outputs information indicating whether Vout is at a predetermined voltage. Specifically, the voltage feedback unit 150 outputs a voltage as an electrical signal between FB and VS of the switching control unit 106. The primary and secondary sides of the voltage feedback unit 150 are insulated from each other, and the voltage feedback unit 150 is a circuit that transmits an electrical signal from the secondary side to the primary side using an element such as a photocoupler. The switching control unit 106 determines the on / off timing of the FET 107 based on the voltage value between FB and VS, and controls the output voltage Vout to be at a predetermined voltage value.

[0017] The installation configuration of the power supply device 100 inside the printer 700 will be described with reference to FIG. 3. In FIG. 3, the height direction of the printer 700 (the direction opposite to the vertical direction) when the printer 700 is installed on a horizontal surface is defined as the Z direction. The direction that intersects with the Z direction and is parallel to the rotation axis direction (main scanning direction) of the photosensitive drum 701 (shown in FIG. 1) is defined as the X direction. The direction that intersects with the X direction and the Z direction is defined as the Y direction. The X direction, Y direction, and Z direction preferably intersect perpendicularly with each other. In the following figures, X, Y, and Z each represent the same direction.

[0018] As shown in Figure 3, printer 700 has a power supply case 200 inside. Power supply case 200 is a box-shaped member indicated by a dotted line, and has a power supply device 100 inside. Power supply device 100 has a circuit board 201 indicated by a dashed line, and a primary electrolytic capacitor 105 mounted on circuit board 201. As mentioned above, power supply device 100 is also provided with various other electrical elements, but these are omitted from Figure 3.

[0019] Circuit board 201 is disposed so as to be approximately perpendicular to the horizontal plane, and its surface extends approximately parallel to the XZ plane. Circuit board 201 is fixed to the inner wall of power supply case 200 with screws 153. Primary electrolytic capacitor 105 is mounted on circuit board 201 so as to protrude toward the negative Y-direction. Meanwhile, commercial power supply 101 (shown in FIG. 2) is connected to inlet 110 via a power cable (not shown), and inlet 110 is connected to power supply device 100 via cable 111.

[0020] FIG. 4 is a perspective view showing the configuration of the power supply device 100 in this embodiment. Only some of the main components are shown here. On the circuit board 201, from top to bottom in the Z direction, are arranged a primary electrolytic capacitor 105, a diode bridge 104, a heat sink 109 (a plate-shaped member), jumper wires 112, and jumper wires 113 (electrical elements). The surface of the circuit board 201 on the negative Y direction on which these components are mounted is referred to as the mounting surface 205. The diode bridge 104 is particularly prone to generating heat among the components on the circuit, and is therefore directly attached to and in contact with the heat sink 109. The jumper wires 112 and 113 are electrical elements for the pattern wiring of the circuit board 201. Here, the potential of the jumper wire 112 is assumed to be equal to DCL, and the potential of the jumper wire 113 is assumed to be equal to DCH.

[0021] As described above, primary electrolytic capacitor 105 protrudes toward the negative Y-axis direction, and its tip is provided with explosion-proof valve 120 (also called a pressure valve). If a voltage exceeding a predetermined value, exceeding the withstand voltage, is applied to electrolytic capacitor 105 due to some abnormality, explosion-proof valve 120 opens and releases gas containing electrolyte to the outside, preventing a rise in pressure inside primary electrolytic capacitor 105. Because this electrolyte is a conductive liquid, if it adheres between jumper wires 112 and 113, which are two electrical elements with different potentials, a short circuit may occur in that path, potentially causing an excessive current to flow. Therefore, it is necessary to prevent the electrolyte from adhering to electronic components such as jumper wires 112 and 113.

[0022] In the configuration of this embodiment, the shape of the heat sink 109 provided between the primary electrolytic capacitor 105 and the jumper wires 112, 113 in the vertical direction is devised to prevent the electrolyte from adhering to the jumper wires 112, 113. As shown in FIG. 4 , the heat sink 109 has a notch 130. The notch 130 is provided on an edge 133 on the circuit board side in the direction in which the primary electrolytic capacitor 105 protrudes (the negative side in the Y direction). The heat sink 109 is also bent at one location and has a surface 131 (a predetermined surface) on which the diode bridge 104 is attached and a surface 132 that intersects with the surface 131 at a substantially right angle. The notch 130 is formed at a corner 134 where the two surfaces intersect.

[0023] The four corners of surface 131 of heat sink 109 are denoted as points A, B, C, and D. Point A is located at the end of surface 131 on the negative Y-direction side and also at the end on the positive X-direction side. Point B is located at the end of surface 131 on the negative Y-direction side and also at the end on the negative X-direction side. Point C is located at the end of slit 130 on the negative Y-direction side. Point D is located at the end of surface 131 on the positive Y-direction side and also at the end on the positive X-direction side.

[0024] Basically, heat sink 109 is mounted so as to be approximately perpendicular to mounting surface 205 of circuit board 201. However, in practice, it may be mounted at an angle to circuit board 201 within a certain degree of accuracy variation. Therefore, in a configuration in which jumper wires 112 and 113 are arranged vertically below point C as shown in FIG. 4, it is necessary to configure heat sink 109 so that electrolyte does not adhere to jumper wires 112 and 113, regardless of the direction in which heat sink 109 is tilted. Figures 5 to 8 below show states in which heat sink 109 is mounted at an angle in different directions.

[0025] 5 is a view of the power supply device 100 and the power supply case 200 viewed along the mounting surface 205 of the circuit board 201. That is, FIG. 5 is a view of the power supply device 100 and the power supply case 200 viewed from the positive side toward the negative side in the X direction. FIG. 5 shows the state when the explosion-proof valve 120 is open, and the electrolyte 114 ejected from the primary electrolytic capacitor 105 splashes around and adheres to the opposing inner wall 220 of the power supply case 200 and the upper surface of the heat sink 109. The heat sink 109 is tilted with respect to the mounting surface 205, and in FIG. 5, the position of the end of the heat sink 109 on the circuit board side (point C) is located vertically lower than the position of the end of the heat sink 109 on the opposite side from the circuit board (point B).

[0026] In FIG. 5, because the heat sink 109 is tilted, the electrolyte 114 that has splashed onto the heat sink 109 flows from point B toward point C. Because the heat sink 109 has the notch 130 (shown in FIG. 4), the electrolyte 114 falls vertically downward at point C. As shown in FIG. 5, the position Y2 of point C in the Y direction is farther from the circuit board 201 than the position Y1 of the jumper wires 112 and 113 that are exposed from the mounting surface 205. In other words, at least a portion of the region in the Y direction where the notch 130 is provided is farther from the mounting surface 205 of the circuit board 201 than the positions where the jumper wires 112 and 113 are provided. Therefore, the electrolyte 114 that has fallen from point C falls to the bottom surface of the power supply case 200 without adhering to the jumper wires 112 and 113.

[0027] In other words, by providing the notch 130, the electrolyte 114, which had previously been guided to a position close to the circuit board 201 and dropped, now drops at a position farther away from the circuit board 201. As a result, it is possible to prevent the electrolyte 114 from adhering to the jumper wires 112, 113 provided vertically below the primary electrolytic capacitor 105.

[0028] FIG. 6 shows a state in which the inclination direction of the heat sink 109 is opposite to that shown in FIG. 6. In FIG. 6, the position (point C) of the end of the heat sink 109 on the circuit board side is positioned vertically higher than the position (point B) of the end on the opposite side from the circuit board. In this case, the electrolyte 114 scattered on the heat sink 109 flows from point C to point B, and the electrolyte 114 falls vertically downward at point B in FIG. 6. As shown in FIG. 6, the position Y4 of point B in the Y direction is farther from the circuit board 201 than the position Y1 of the jumper wires 112 and 113 exposed from the mounting surface 205 in the Y direction. Therefore, the electrolyte 114 falling from point B falls to the bottom surface of the power supply case 200 without adhering to the jumper wires 112 and 113.

[0029] Furthermore, position Y4 of point B in the Y direction is farther from circuit board 201 than position Y3 of the tip of primary electrolytic capacitor 105. In other words, heat sink 109 protrudes further from circuit board 201 than primary electrolytic capacitor 105. This allows heat sink 109 to act as a kind of umbrella for jumper wires 112 and 113, preventing electrolyte 114 spurting from the tip of primary electrolytic capacitor 105 from reflecting off inner wall 220 and adhering to jumper wires 112 and 113. This effect can also be obtained in the state shown in FIG. 5.

[0030] Fig. 7 is a view of power supply device 100 viewed in a direction perpendicular to mounting surface 205 of circuit board 201. In other words, Fig. 7 is a view of power supply device 100 viewed from the negative side toward the positive side in the Y direction. As shown in Fig. 7, surface 131 of heat sink 109 on which diode bridge 104 is attached extends in a direction intersecting the vertical direction and is tilted with respect to the horizontal direction so that point A is located vertically higher than point B.

[0031] At this time, the electrolyte 114 scattered on the heat sink 109 flows from the downstream end in the vertical direction, that is, from point A toward point B. Because the surface 131 of the heat sink 109 is tilted with respect to the horizontal, the electrolyte 114 is guided to a corner 134. By bending the heat sink 109 to form a corner 134, the electrolyte 114 that has flowed toward point B can be collected at the corner 134. Thereafter, as shown in FIG. 5 or FIG. 6, the electrolyte 114 collected at the corner 134 flows toward either point B or point C depending on the tilt direction of the heat sink 109. However, in either state, the electrolyte 114 does not adhere to the jumper wires 112 and 113, as explained with reference to FIGS. 5 and 6.

[0032] Figure 8 shows a state in which the inclination direction of heat sink 109 is opposite to that in Figure 7. In Figure 7, surface 131 of heat sink 109 extends in a direction intersecting the vertical direction and is inclined with respect to the horizontal direction so that point A is located vertically lower than point B. In this configuration, electrolyte 114 that has splashed onto heat sink 109 flows from point B toward point A and falls to a location away from the positions where jumper wires 112 and 113 are provided in the X direction. This prevents electrolyte 114 from adhering to jumper wires 112 and 113.

[0033] As described above, in a configuration in which jumper wires 112 and 113 are provided vertically below point C, by providing notch 130, it is possible to prevent electrolyte 114 from adhering to the electrical element regardless of the direction in which heat sink 109 is tilted.

[0034] 5 to 8, a configuration has been described in which the heat sink 109 is inclined with respect to the mounting surface 205 of the circuit board 201, but the heat sink 109 may not be inclined with respect to the mounting surface 205, and may be completely perpendicular to the mounting surface 205.

[0035] In the above-described configuration, the jumper wires 112 and 113 are provided vertically below point C. However, if the jumper wires 112 and 113 are provided vertically below point D, a notch may be provided on the side of point D. This configuration will be described below.

[0036] 9 is a perspective view of power supply device 100 in which jumper wires 112 and 113 are provided vertically below point D. In addition to notch 130, heat sink 109 is newly provided with notch 135 on the point D side. Point E is located at the end of notch 135 on the negative side in the Y direction. Note that notch 130 does not necessarily have to be provided.

[0037] Fig. 10 is a view of power supply device 100 shown in Fig. 8 viewed in a direction perpendicular to mounting surface 205 of circuit board 201. Fig. 10 shows a state in which surface 131 of heat sink 109 is tilted with respect to the horizontal direction due to the influence of precision variations. In this case, point B is tilted vertically above point A, and therefore electrolyte 114 splashed onto heat sink 109 flows from point B toward point A.

[0038] 11 is a view of power supply device 100 and power supply case 200 shown in FIG. 8 viewed along mounting surface 205 of circuit board 201. In the configuration of FIG. 10, point E is located vertically below point A, so electrolyte 114 flows from point A toward point E. As a result, electrolyte 114 falls vertically downward at point E. Position Y6 of point E in the Y direction is farther from circuit board 201 than position Y5 of jumper wires 112 and 113 exposed from mounting surface 205 in the Y direction. Therefore, electrolyte 114 falling from point E falls to the bottom surface of power supply case 200 without adhering to jumper wires 112 and 113.

[0039] Note that, as for the state in which the heat sink 109 is mounted tilted in a direction different from that shown in FIGS. 10 and 11, the contents have already been explained using FIGS. 5 to 8, so explanation thereof will be omitted here.

[0040] As described above, in a configuration in which jumper wires 112 and 113 are provided vertically below point D, providing notch 135 can prevent electrolyte 114 from adhering to jumper wires 112 and 113.

[0041] In the first embodiment described above, a configuration in which a notch is provided at the end of heat sink 109 has been described, but the present invention is not limited to this. As shown in Fig. 12, a configuration in which a hole 136 is provided inside heat sink 109 may also be used. Since the electrolyte that splashes onto heat sink 109 falls vertically downward from hole 136 located away from mounting surface 205 of circuit board 201, this configuration can also prevent the electrolyte from adhering to jumper wires 112 and 113.

[0042] In addition, in the first embodiment described above, a configuration in which a notch or a hole is provided in the corner 134 of the heat sink 109 has been described, but the present invention is not limited to this. For example, in Fig. 7, the notch 130 is provided in the corner 134, that is, at the downstream end in the vertical direction of the heat sink 109 which is tilted with respect to the horizontal direction, but the notch 130 may be provided in a position slightly shifted from the corner 134 on the positive side in the X direction.

[0043] As described above, according to this embodiment, by providing the heat sink 109 with a notch or a hole, it is possible to prevent the electrolyte spurting out from the primary electrolytic capacitor 105 from adhering to the jumper wires 112 and 113 .

[0044] <Example 2> In the first embodiment, a configuration was described in which a heat sink 109 mounted on a circuit board 201 is used to prevent the electrolyte from adhering to the jumper wires 112 and 113. However, depending on the configuration of the power supply device 100, the heat sink 109 may not be provided. Therefore, in this embodiment, a configuration will be described in which a dedicated member for preventing the electrolyte from adhering to the jumper wires 112 and 113 is intentionally provided at an angle with respect to the mounting surface 205. The basic device configuration is the same as in the first embodiment, so a description thereof will be omitted. Here, a configuration different from the first embodiment will be described.

[0045] Fig. 13 shows the configuration of power supply device 100 provided with induction plate 202 (plate-shaped member) for electrolyte 114. Fig. 13 is a view of power supply device 100 viewed along mounting surface 205 of circuit board 201. In Fig. 13, induction plate 202 is located between primary electrolytic capacitor 105 and diode bridge 104 in the Z direction, and is installed so that it tilts in the -Z direction as it moves away from circuit board 201.

[0046] Guide plate 202 is a member for guiding electrolyte 114 to a position away from jumper wires 112 and 113, and is a member molded from, for example, resin. Furthermore, guide plate 202 is not tilted relative to mounting surface 205 within the range of accuracy variation, but is attached to circuit board 201 in an intentionally tilted state. Specifically, if the tilt angle of guide plate 202 relative to an auxiliary line extending perpendicular to mounting surface 205 of circuit board 201 is θ, then θ is preferably 10 degrees or greater.

[0047] In this configuration, the electrolyte 114 adhering to the guide plate 202 flows toward the negative Y-direction and falls in the -Z direction from the tip 203 of the guide plate 202 on the negative Y-direction side. Therefore, the electrolyte 114 does not adhere to the jumper wires 112 and 113, but falls to the bottom surface of the power supply case 200.

[0048] As described above, according to this embodiment, by providing the guide plate 202 that guides the electrolyte 114, it is possible to prevent the electrolyte sprayed from the primary electrolytic capacitor 105 from adhering to the jumper wires 112 and 113, even in the absence of a plate-like member such as the heat sink 109.

[0049] <Modification> In the above-described first embodiment, a configuration in which a notch or a hole is provided in the heat sink 109 has been described, but the present invention is not limited to this. Instead of the heat sink 109, the guide plate 202 described in the second embodiment may be provided, and the guide plate 202 may be provided with a notch or a hole.

[0050] In the second embodiment, the guide plate 202 is intentionally tilted relative to the mounting surface 205. However, the present invention is not limited to this. Instead of the guide plate 202, the heat sink 109 described in the first embodiment may be provided, and the heat sink 109 may be mounted at an intentional tilt relative to the mounting surface 205.

[0051] In addition, in the above-described first and second embodiments, the diode bridge 104 is attached to the heat sink 109, but the present invention is not limited to this configuration. Other components that are likely to generate heat include the FET 107, which is a switching element, and a rectifier diode (not shown) included in the rectifier unit 151 of the secondary side circuit, and the like, and these components may be in contact with the heat sink 109.

[0052] Furthermore, in the above-described first and second embodiments, the jumper wires 112 and 113 are used as examples of electrical elements provided vertically below the primary electrolytic capacitor 105. However, two electrical elements are not necessarily provided. For example, a configuration in which only the jumper wire 112 is provided may be used. In this case, if electrolyte adheres to the periphery of the jumper wire 112, a short circuit may occur between the jumper wire 112 and the bottom surface of the power supply case 200 or the ground. Furthermore, because the heat sink 109 has a predetermined potential, a short circuit may also occur between the jumper wire 112 and the heat sink 109. Furthermore, the electrical element is not limited to the jumper wire 112, but may be another electrical element provided in the primary circuit of the transformer 108, such as a resistor or a diode.

Claims

1. an image forming means for forming an image on a recording material; a power supply device for supplying power to the image forming means, wherein a circuit board of the power supply device is disposed so as to intersect with a horizontal plane, The power supply device an electrolytic capacitor extending in a first direction protruding from a mounting surface of the circuit board, the electrolytic capacitor having an explosion-proof valve that opens to eject the electrolyte therein to the outside when a voltage equal to or greater than a predetermined value is applied; an electric element provided below the electrolytic capacitor in the vertical direction and exposed from the mounting surface; a plate-like member that is provided between the electrolytic capacitor and the electric element in the vertical direction, and that has a predetermined surface that extends in a second direction that intersects with the vertical direction when viewed in a direction perpendicular to the mounting surface of the circuit board; An image forming apparatus characterized in that a notch or hole is formed in the plate-like member, and at least a portion of the area in which the notch or hole is provided is located farther from the mounting surface of the circuit board in the first direction than the position in which the electrical element is provided.

2. 2. The image forming apparatus according to claim 1, wherein the notch is formed on the edge of the plate-like member facing the circuit board in the first direction, and the position of the end of the notch opposite the circuit board is located farther from the mounting surface of the circuit board in the first direction than the position where the electrical element is provided.

3. 3. The image forming apparatus according to claim 1, wherein the plate-like member is bent at least at one location to form a corner, and the notch or the hole is formed in the corner.

4. An image forming apparatus according to any one of claims 1 to 3, characterized in that when viewed in a direction perpendicular to the mounting surface of the circuit board, the second direction is inclined with respect to the horizontal direction, and the notch or the hole is formed at the downstream end in the vertical direction of the plate-like member.

5. An image forming apparatus as described in any one of claims 1 to 4, characterized in that the plate-shaped member is inclined obliquely with respect to the mounting surface so that the position of the end of the plate-shaped member on the circuit board side in the first direction is located lower in the vertical direction than the position of the end of the plate-shaped member on the opposite side of the circuit board in the first direction.

6. An image forming apparatus as described in any one of claims 1 to 5, characterized in that the plate-like member protrudes beyond the tip of the electrolytic capacitor in the first direction.

7. an image forming means for forming an image on a recording material; a power supply device for supplying power to the image forming means, wherein a circuit board of the power supply device is disposed so as to intersect with a horizontal plane, The power supply device an electrolytic capacitor extending in a first direction protruding from a mounting surface of the circuit board, the electrolytic capacitor having an explosion-proof valve that opens to eject the electrolyte therein to the outside when a voltage equal to or greater than a predetermined value is applied; an electric element provided below the electrolytic capacitor in the vertical direction and exposed from the mounting surface; a plate-like member that is provided between the electrolytic capacitor and the electric element in the vertical direction, and that has a predetermined surface that extends in a second direction that intersects with the vertical direction when viewed in a direction perpendicular to the mounting surface of the circuit board; an electrolytic capacitor disposed on the mounting surface of the image forming apparatus, the electrolytic capacitor being disposed on the mounting surface of the image forming apparatus; the electrolytic capacitor being disposed on the mounting surface of the image forming apparatus; the electrolytic capacitor being disposed on the mounting surface of the image forming apparatus;

8. 8. The image forming apparatus according to claim 7, wherein the plate-like member is inclined at an angle of 10 degrees or more with respect to a direction perpendicular to the mounting surface of the circuit board.

9. 9. The image forming apparatus according to claim 1, wherein the plate-like member is a heat sink for dissipating heat from the power supply device.

10. It has a diode bridge for converting AC supplied from a commercial power source into DC, 10. The image forming apparatus according to claim 9, wherein the diode bridge is in contact with the heat sink.

11. 11. The image forming apparatus according to claim 1, wherein the plate-like member is a guide plate that guides the electrolyte in a predetermined direction.

12. 12. An image forming apparatus according to claim 1, further comprising a transformer having a primary winding and a secondary winding, and outputting a voltage to the secondary winding in accordance with a voltage input to the primary winding, wherein the electrical element is a jumper wire provided in a primary side circuit of the transformer.

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