JP2009182098A - Power unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power unit, which never scatters an electrolyte to a printed circuit board and other live parts without disturbing a function of an explosion-proof valve of an electrolytic capacitor, with inexpensive constitution. <P>SOLUTION: The power unit A includes the printed circuit board 13 for mounting an electronic component, a rectifying circuit 53 for rectifying an output of an AC waveform from an AC power source, and the electrolytic capacitor 10 having the explosion-proof valve 15 for converting the output having been rectified by the rectifying circuit 53 into DC electric power by smoothing a pulsating waveform. The power unit A further has an explosion-proof valve cover portion 16 for a cap B mounted covering the explosion-proof valve 15, and a duct portion 17 which is connected to the explosion-proof valve cover portion 16 and secures ventilation to the explosion-proof valve 15, wherein the duct portion 17 guides the electrolyte 14 to a power source chassis 11 to discharge it when the explosion-proof valve 15 operates and the electrolytic capacitor 10 spouts out the electrolyte 14. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a power supply device, and more particularly to a power supply device having an electrolytic capacitor having a circuit for rectifying and smoothing an AC power supply and having an explosion-proof valve in the smoothing circuit.

  The power supply devices installed in recent electronic devices do not obtain the output by converting the AC power supply (commercial power supply) directly into the transformer for the purpose of miniaturization, weight reduction, and cost reduction. The following is adopted. That is, a switching power supply is generally employed in which an AC power supply is once rectified and smoothed to be converted into a DC power supply, and the DC power supply is input to a transformer and switched to obtain a desired output. There are various power supply systems such as a flyback converter system, a forward converter system, and a current resonance system as switching power supply systems. All of these power supplies rectify and smooth an AC power supply at the input section to create a direct current. It has a rectifier circuit and a smoothing circuit for obtaining a power source. The smoothing circuit is a circuit using a rectified pulsating waveform as a DC power supply, and an electrolytic capacitor capable of obtaining a large capacitance at low cost is generally used for the circuit portion. As the name suggests, this electrolytic capacitor is an element that utilizes an electrolytic action. If an excessive voltage is applied to the electrolytic capacitor, a large amount of gas is generated. Therefore, the electrolytic capacitor is provided with a notch called an explosion-proof valve for preventing gas from accumulating inside the electrolytic capacitor and increasing the pressure inside the electrolytic capacitor and ejecting the electrolytic solution. When an overvoltage is applied to the electrolytic capacitor and the explosion-proof valve is activated, the electrolyte will spout from the inside, but this electrolyte is flammable, and the electrolyte will scatter to the power supply and other live parts. There is a risk that.

As a countermeasure, a proposal has been made to extinguish a suffocation as an oxygen-deficient state when the explosion-proof valve is operated by providing a cap made of an incombustible material on the explosion-proof valve portion of the electrolytic capacitor (see, for example, Patent Document 1 and Patent Document 2). In addition, a configuration has been proposed in which the fuse of the AC input section is cut when an overvoltage is detected so that the explosion-proof valve does not operate when an overvoltage is applied (see, for example, Patent Document 3).
JP 2002-345247 A JP 2002-345262 A JP 2006-288155 A

  However, the proposals in Patent Document 1 and Patent Document 2 described above impede the original function of the name, which is an explosion-proof valve for an electrolytic capacitor. In other words, even if gas generation inside the electrolytic capacitor continues, there is a possibility that the gas will be prevented from being discharged by the cap, and the internal pressure will rise to the limit that the case of the electrolytic capacitor can withstand and the electrolyte will leak. There is. In Patent Document 3, although the explosion-proof valve itself is not operated when an overvoltage is detected and safety is high, it is necessary to add a relatively expensive circuit in order to realize the function.

  The present invention has been made in view of the above-described problems. A power supply device that does not scatter the electrolytic solution on a printed circuit board or other live parts without interfering with the function of the explosion-proof valve of the electrolytic capacitor is inexpensive. The problem is to provide a simple configuration.

  In order to solve the above problems, a power supply device of the present invention has the following configuration.

  (1) A printed circuit board for mounting electronic components, a rectifying element for rectifying the output of an AC waveform from an AC power supply, and smoothing the output rectified by the rectifying element and converting it to a DC power supply An electrolytic capacitor having an explosion-proof valve for the power supply apparatus, a lid member that covers and installs the explosion-proof valve, and a duct that is connected to the lid member and ensures ventilation to the explosion-proof valve And the duct guides and discharges the electrolytic solution to a non-active part when the explosion-proof valve is activated and the electrolytic solution is ejected from the inside of the electrolytic capacitor.

  According to the present invention, the electrolytic solution can be safely discharged without splashing the printed circuit board or other live parts without interfering with the function of the explosion-proof valve of the electrolytic capacitor mounted on the power supply device. The power supply device can be provided with an inexpensive configuration.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to examples.

  First, a power supply device A targeted by the present invention will be briefly described with reference to FIG. The power supply device A is fastened to the power supply chassis 11 (see FIG. 3) (non-active part) with screws, and is grounded via the power supply chassis 11 and simultaneously fixed to the electronic device body. The power supply device A is provided with an input terminal 50, and an AC power supply C (commercial power supply) is supplied to the power supply device A through the input terminal 50. When the AC power source C supplied to the power supply device A reaches the rectifier circuit 53 (rectifier element) via the current fuse 51 and the input filter circuit 52 in order, a sine waveform that is an output of the AC waveform of the AC power source C is obtained. Rectified and outputs a pulsating waveform in which the negative waveform is folded back to the positive side. Then, when the output of the pulsating flow waveform is input to the smoothing circuit 54, it is smoothed and converted to a DC power source substantially equal to the peak value of the sine waveform. The DC power source converted by the smoothing circuit 54 is input from the plus terminal to the transformer 55 and further fed back to the minus terminal via the transistor 56. The timing of ON / OFF (hereinafter referred to as ON / OFF) of the transistor 56 is controlled by the control circuit 57, and the power source of the control circuit 57 is generated by the transformer 55. A secondary side rectifier circuit 58 exists at the output destination converted by the transformer 55, and is smoothed to a predetermined voltage by the secondary side rectifier circuit 58 and output from the output terminal 59 to the outside of the power supply device A. The output of the secondary side rectifier circuit 58 is input to the output detection circuit 60, and the output result of the output detection circuit 60 is sent to the primary side control circuit 57 by an element (for example, a photocoupler) that insulates primary and secondary. Entered. The control circuit 57 determines the ON / OFF timing of the transistor 56 based on the output result of the output detection circuit 60.

  Next, in the power supply device A as described above, when the explosion-proof valve (15) of the electrolytic capacitor (10) used in the smoothing circuit 54 is activated and the electrolytic solution (14) is ejected, the electrolytic solution (14) The structure which discharges | emits safely is demonstrated below using FIGS.

  FIG. 2 shows the cap B in this embodiment. 2A is a view of the cap B as viewed from above, and FIG. 2B is a view of the cap B as viewed from the side. The cap B covers the explosion-proof valve 15 of the electrolytic capacitor 10 and is attached to the explosion-proof valve cover portion 16 (lid member). The duct portion 17 (connected to the explosion-proof valve cover portion 16 and ensures ventilation to the explosion-proof valve 15) Duct) and a hook portion 18 (fixing means) at the tip of the duct portion 17. The explosion-proof valve cover portion 16 has a sufficient distance d (for example, 3 mm) so as not to interfere with the operation of the explosion-proof valve 15. FIG. 3 is a side view of the power supply device A when the cap B is covered from the upper part of the electrolytic capacitor 10. The explosion-proof valve cover portion 16 of the cap B completely covers the explosion-proof valve 15, and the hook portion 18 provided at the tip of the duct portion 17 is inserted into a hole provided in the printed circuit board 13 on which electronic components are mounted. Fixed. The cap B is made of a non-flammable synthetic resin, and it is desirable to use PPS (polyphenylene sulfide) or the like having high heat resistance.

  When an overvoltage is applied to the electrolytic capacitor 10 for some reason, a large amount of gas is generated inside the electrolytic capacitor 10, the pressure inside the electrolytic capacitor 10 rises, and the explosion-proof valve 15 operates. When the explosion-proof valve 15 is operated, the electrolytic solution 14 is ejected from the inside of the electrolytic capacitor 10, and the ejected electrolytic solution 14 is connected to the printed circuit board through a duct portion 17 connected to the explosion-proof valve covering portion 16 as indicated by an arrow in the figure. 13 is discharged to the power supply chassis 11 outside the power supply device A through the holes 13. The hook portion 18 is a mechanism that is locked when inserted into the printed circuit board 13 so that the cap B does not fly off due to the momentum of the gas ejected from the electrolytic capacitor 10.

  Here, the duct part 17 and the hook part 18 may be provided with two or more instead of one. A cap B provided with two duct portions 17 and two hook portions 18 is shown in FIGS. 4A is a view of the cap B viewed from above, and FIG. 4B is a view of the cap B viewed from the lateral direction. FIG. 5 is a side view of the power supply device A when the cap B is covered from the top of the electrolytic capacitor 10. If it is this structure, since the escape route of gas when gas ejects can be taken largely, the pressure concerning a cap can be reduced. Furthermore, since the holding force to the printed circuit board 13 is increased because the lock is performed at two places, the lock can be fixed more strongly than when the lock is made at one place.

  In the present embodiment, the electrolyte solution 14 ejected from the electrolytic capacitor 10 was discharged to the power supply chassis 11 directly below the printed circuit board 13. However, the discharge destination is not limited to the power supply chassis 11 and may be anywhere as long as it is a safe place such as a non-energized area (non-active part) that is not a live part. The same applies to Examples 2 to 6 described below.

  The second embodiment of the present invention will be described with reference to FIGS. Since the power supply device A is the same as that of the first embodiment, the description thereof will be omitted and the description will be made using the same reference numerals.

  FIG. 6 shows the cap B in this embodiment. 6A is a view of the cap B as viewed from above, and FIG. 6B is a view of the cap B as viewed from the side. The cap B includes an explosion-proof valve cover portion 16 that covers the explosion-proof valve 15 of the electrolytic capacitor 10, a duct portion 17, and a screw stopper 21 (fixing means). The explosion-proof valve cover portion 16 is blocked when the explosion-proof valve 15 is operated. The distance d is sufficiently secured so as not to occur (for example, 3 mm). The screw stopper 21 is provided with a hole through which the screw 22 passes. Note that the cap B is made of a non-flammable synthetic resin, and it is desirable to use PPS or the like having high heat resistance.

  FIG. 7 is a side view of the power supply device A when the cap B is covered from the top of the electrolytic capacitor 10. The explosion-proof valve cover portion 16 of the cap B completely covers the explosion-proof valve 15, and the screw stopper 21 provided at the tip of the duct portion 17 is fixed together with the printed board 13 by screws 22 and nuts 23. The duct portion 17 passes through a hole provided in the printed circuit board 13.

  According to the above configuration, even when the explosion-proof valve 15 of the electrolytic capacitor 10 is activated and the electrolytic solution 14 is ejected from the electrolytic capacitor 10, the electrolytic solution 14 is discharged as follows. That is, the sprayed electrolyte 14 passes through the hole of the printed circuit board 13 through the duct portion 17 connected to the explosion-proof valve cover portion 16 and is safely discharged to the power supply chassis 11 outside the power supply device A. In this embodiment, the number of parts and the mounting space are increased as compared with the first embodiment, but the cap B can be fixed to the printed circuit board 13 more strongly than the first embodiment. In this embodiment, although only one screw fixing portion 21 is provided, a plurality of screw fixing portions 21 may be arranged in order to fix more strongly.

  A third embodiment of the present invention will be described with reference to FIGS. Since the power supply device A is the same as that of the first embodiment, the description thereof will be omitted and the description will be made using the same reference numerals.

  FIG. 8 shows the cap B in this embodiment. 8A is a view of the cap B as viewed from above, and FIG. 8B is a view of the cap B as viewed from the side. The cap B includes an explosion-proof valve covering portion 16 that covers the explosion-proof valve 15 of the electrolytic capacitor 10, a duct portion 17, a lead wire fixing portion 25, and a lead wire 26 (fixing means). The explosion-proof valve covering portion 16 has a sufficient distance d (for example, 3 mm) so as not to interfere with the operation of the explosion-proof valve 15. The lead wire fixing portion 25 is fixed by caulking to the duct portion 17, and two lead wires 26 are provided. Note that the cap B is made of a non-flammable synthetic resin, and it is desirable to use PPS or the like having high heat resistance.

  FIG. 9 is a side view of the power supply device A when the cap B is covered from the upper part of the electrolytic capacitor 10. The explosion-proof valve covering portion 16 of the cap B completely covers the explosion-proof valve 15, and the lead wire 26 provided on the lead wire fixing portion 25 passes through the hole of the printed circuit board 13. The pattern surface of the printed circuit board 13 is provided with component lands in the holes of the lead wires 26, and can be automatically fixed to the printed circuit board 13 without human intervention by flowing the printed circuit board 13 through a solder flow tank. It has become. The duct portion 17 passes through a hole provided in the printed circuit board 13.

  According to the above configuration, even when the explosion-proof valve 15 of the electrolytic capacitor 10 is activated and the electrolytic solution 14 is ejected from the inside of the electrolytic capacitor 10, the ejected electrolytic solution 14 is connected to the explosion-proof valve covering portion 16. 17 through the hole in the printed circuit board 13. Then, it is safely discharged to the power supply chassis 11 outside the power supply device A. In this embodiment, when flowing the solder flow tank to mount the components on the printed circuit board 13, the cap B can be mounted at the same time, so that workability can be improved.

  The fourth embodiment of the present invention will be described with reference to FIG. Since the power supply device A is the same as that of the first embodiment, the description thereof will be omitted and the description will be made using the same reference numerals.

  FIG. 10 is a side view of the power supply device A when the cap B is covered from the upper part of the electrolytic capacitor 10. The cap B includes an explosion-proof valve cover portion 16 and a duct portion 17 that cover the explosion-proof valve 15 of the electrolytic capacitor 10, and the duct portion 17 passes through a hole provided in the printed circuit board 13. The explosion-proof valve covering portion 16 has a sufficient distance d (for example, 3 mm) so as not to interfere with the operation of the explosion-proof valve 15. Note that the cap B is made of a non-flammable synthetic resin, and it is desirable to use PPS or the like having high heat resistance.

  The cap B is fixed to the electrolytic capacitor 10 and the printed board 13 by an epoxy resin adhesive 30 (fixing means). In this embodiment, although fixed to both the electrolytic capacitor 10 and the printed circuit board 13, it is of course possible to fix either one as long as the fixing strength is sufficient.

  According to the above configuration, even when the explosion-proof valve 15 of the electrolytic capacitor 10 is activated and the electrolytic solution 14 is ejected from the inside of the electrolytic capacitor 10, the ejected electrolytic solution 14 is connected to the explosion-proof valve covering portion 16. 17 through the hole in the printed circuit board 13. Then, it is safely discharged to the power supply chassis 11 outside the power supply device A.

  The fifth embodiment of the present invention will be described with reference to FIGS. Since the power supply device A is the same as that of the first embodiment, the description thereof will be omitted and the description will be made using the same reference numerals.

  FIG. 11 shows the cap B in this embodiment. FIG. 11A is a view of the cap B as viewed from above, and FIG. 11B is a view of the cap B as viewed from the lateral direction. The cap B includes an explosion-proof valve cover portion 16 that covers the explosion-proof valve 15 of the electrolytic capacitor 10, a duct portion 17, and a rubber portion 35 (fixing means). The explosion-proof valve cover portion 16 is obstructed when the explosion-proof valve 15 is operated. The distance d is sufficiently secured (for example, 3 mm). The cap B is formed of a nonflammable synthetic resin, and it is desirable to use PPS or the like having high heat resistance.

  FIG. 12 is a side view of the power supply device A when the cap B is covered from the upper part of the electrolytic capacitor 10. The outer diameter of the electrolytic capacitor 10 is shorter than the distance y between the rubber portions 35. When the electrolytic capacitor 10 is covered with the cap B, the electrolytic capacitor 10 is inserted in a state where the rubber portion 35 contracts and the electrolytic capacitor 10 is pressurized. . After the insertion, the cap B is fixed to the electrolytic capacitor 10 by the restoring force of the rubber part 35. Here, the duct portion 17 passes through a hole provided in the printed circuit board 13.

  According to the above configuration, even when the explosion-proof valve 15 of the electrolytic capacitor 10 is activated and the electrolytic solution 14 is ejected from the inside of the electrolytic capacitor 10, the ejected electrolytic solution 14 is connected to the explosion-proof valve covering portion 16. 17 through the hole in the printed circuit board 13. Then, it is safely discharged to the power supply chassis 11 outside the power supply device A.

  The sixth embodiment of the present invention will be described with reference to FIGS. Since the power supply device A is the same as that of the first embodiment, the description thereof is omitted and the same reference numerals are used.

  In Examples 1 to 5, the fixing means for the cap B was either fixed to the electrolytic capacitor 10 or fixed to the printed circuit board 13. In the present embodiment, a configuration that does not require the cap B to be fixed will be described below.

  FIG. 13 is a side view of the power supply device A when the cap B is covered from the upper part of the electrolytic capacitor 10. A ceiling 40 (ceiling member) is present at a distance h above the cap B. The member of the ceiling 40 may be anything such as a main body housing or another printed circuit board. The cap B includes an explosion-proof valve cover portion 16 and a duct portion 17 that cover the explosion-proof valve 15 of the electrolytic capacitor 10, and the explosion-proof valve cover portion 16 is sufficiently distanced so as not to interfere with the operation of the explosion-proof valve 15. d is secured (for example, 3 mm). The cap B is made of non-combustible synthetic resin, and it is desirable to use PPS or the like having high heat resistance.

  When an overvoltage is applied to the electrolytic capacitor 10 for some reason, a large amount of gas is generated inside the electrolytic capacitor 10, the pressure inside the electrolytic capacitor 10 rises, and the explosion-proof valve 15 operates. When the explosion-proof valve 15 is activated, the gas and the electrolytic solution 14 are ejected from the inside of the electrolytic capacitor 10, and the cap B that is not fixed is blown above the electrolytic capacitor 10 by the pressure of the gas. Here, if the lengths of m and n in FIG. 13 are in a relationship of m, n> h with respect to h, the cap B will not be blown further upward when it reaches the ceiling 40. Fixed. That is, the cap B is fixed to the electrolytic capacitor 10, and the ejected electrolyte 14 passes through the hole of the printed circuit board 13 through the duct portion 17 connected to the explosion-proof valve cover portion 16, and the power supply chassis 11. Will be discharged.

  In the present embodiment, when the lengths of m and n are shorter than h, the protrusion 41 may be provided on the cap B as shown in FIG. The height of the protrusion 41 is determined so that the distance x between the protrusion 41 and the ceiling 40 is in a relationship of m, n> x with respect to m, n. Then, even when the explosion-proof valve 15 of the electrolytic capacitor 10 is operated, the cap B is fixed in a state where the protrusion 41 reaches the ceiling 40. The ejected electrolyte 14 is discharged to the power supply chassis 11 outside the power supply device A through the hole of the printed circuit board 13 through the duct portion 17 connected to the explosion-proof valve cover portion 16.

It is a figure showing the power supply device which concerns on Examples 1-6 of this invention. It is a figure showing the cap of the electrolytic capacitor which concerns on Example 1 of this invention, (a) is the figure which looked at the cap B from the upper part, (b) is the figure which looked at the cap B from the horizontal direction. It is a figure showing the state which covered the cap of the electrolytic capacitor which concerns on Example 1 of this invention on the electrolytic capacitor. It is a figure showing the cap of the electrolytic capacitor which concerns on Example 1 of this invention, (a) is the figure which looked at the cap B from the upper part, (b) is the figure which looked at the cap B from the horizontal direction. It is a figure showing the state which covered the cap of the electrolytic capacitor which concerns on Example 1 of this invention on the electrolytic capacitor. It is a figure showing the cap of the electrolytic capacitor which concerns on Example 3 of this invention, (a) is the figure which looked at the cap B from the upper part, (b) is the figure which looked at the cap B from the horizontal direction. It is a figure showing the state which covered the cap of the electrolytic capacitor which concerns on Example 2 of this invention on the electrolytic capacitor. It is a figure showing the cap of the electrolytic capacitor which concerns on Example 3 of this invention, (a) is the figure which looked at the cap B from the upper part, (b) is the figure which looked at the cap B from the horizontal direction. It is a figure showing the state which covered the cap of the electrolytic capacitor which concerns on Example 3 of this invention on the electrolytic capacitor. It is a figure showing the state which covered the cap of the electrolytic capacitor which concerns on Example 4 of this invention on the electrolytic capacitor. It is a figure showing the cap of the electrolytic capacitor which concerns on Example 5 of this invention, (a) is the figure which looked at the cap B from the upper part, (b) is the figure which looked at the cap B from the horizontal direction. It is a figure showing the state which covered the cap of the electrolytic capacitor which concerns on Example 5 of this invention on the electrolytic capacitor. It is a figure showing the state which covered the cap of the electrolytic capacitor which concerns on Example 6 of this invention on the electrolytic capacitor. It is a figure showing the state which covered the cap of the electrolytic capacitor which concerns on Example 6 of this invention on the electrolytic capacitor.

Explanation of symbols

A Power supply B Cap C AC power supply (Commercial power supply)
11 Power supply chassis (non-active part)
13 Printed Circuit Board 14 Electrolyte 15 Explosion Proof Valve 16 Explosion Proof Valve Cover (Cover Member)
17 Duct section (duct)
18 Hook (fixing means)
21 Screw fixing part (fixing means)
22 Screw 23 Nut 25 Lead wire fixing part 26 Lead wire (fixing means)
30 Adhesive (fixing means)
35 Rubber part (fixing means)
40 Ceiling (ceiling)
41 Projection 50 Input Terminal 51 Current Fuse 52 Input Filter Circuit 53 Rectifier Circuit (Rectifier Element)
54 Smoothing circuit 55 Transformer 56 Transistor 57 Control circuit 58 Secondary side rectification circuit 59 Output terminal 60 Output detection circuit

Claims (5)

A printed circuit board for mounting electronic components, a rectifying element for rectifying the output of an AC waveform from an AC power supply, and an explosion-proof for smoothing the output rectified by the rectifying element and converting it to a DC power supply A power supply device comprising an electrolytic capacitor having a valve,
A lid member mounted over the explosion-proof valve;
A duct connected to the lid member and ensuring ventilation to the explosion-proof valve,
The power supply device, wherein the duct guides and discharges the electrolytic solution to a non-active part when the explosion-proof valve is operated and the electrolytic solution is ejected from the inside of the electrolytic capacitor. The duct has a fixing means at the tip thereof,
The power supply apparatus according to claim 1, wherein the fixing unit is fixed to the printed circuit board. The lid member has a fixing means,
The power supply apparatus according to claim 1, wherein the fixing unit is fixed to the electrolytic capacitor. The lid member has a ceiling member at the top thereof,
The power supply device according to claim 1, wherein the lid member is fixed to the ceiling member when the explosion-proof valve is operated. A plurality of the ducts;
The power supply apparatus according to claim 1, wherein the duct has a fixing means at a tip portion thereof.

Images