JP2000269670A - Switching power-supply apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a switching power-supply apparatus which restrains heat generated from a heat generating electronic component from reaching a heat affected electronic component, in which the heat generating electronic component and the thermally influenced electronic component are provided inside the same casing and whose service life can be made long. SOLUTION: A housing space SP is partitioned into two subspaces SSP1, SSP2 by a board 92, which is arranged on the surface side of a board 91. Then, an electrolytic capacitor 301 and an electrolytic capacitor 302 which correspond to heat affected components are arranged in the second subspace SSP2. A diode for rectification, a power transistor for switching, a transistor 24 and the like which correspond to heat generating components are arranged in the first subspace SSP1. The board 92 functions as a heat insulating plate to prevent heat inside the first subspace SSP1 from reaching the second subspace SSP2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a switching power supply having a plurality of electronic components mounted on a substrate.

[0002]

2. Description of the Related Art As a switching power supply of this type, a switching power supply having an internal circuit configuration as shown in FIG. 6 is known. This switching power supply device is a device that converts an alternating current input through an input terminal unit 10 into a direct current having a predetermined output voltage, and outputs the direct current through an output terminal unit 12. In this switching power supply device, the alternating current input to the input terminal 10 is supplied to the filter circuit 16, the input side rectifier circuit 18, the input side smoothing circuit 20 via the fuse 14.
The DC voltage passes through the switching circuit 22 and is supplied to the primary side of the transformer 24. Here, the switching circuit 22 performs ON / OFF control of a DC applied to the transformer 24 based on a control signal from the control circuit 26, whereby an AC is output from the secondary side of the transformer 24. Then, the AC output from the transformer 24 is converted into DC by the output-side rectifier circuit 28 and the output-side smoothing circuit 30, and is provided to the output terminal unit 12.

Further, in this switching power supply, on the output side, a DC voltage output from the output side smoothing circuit 30 is detected by an overvoltage detection circuit 32, and a signal corresponding to the voltage value is supplied to a control circuit 26. The detection circuit 36 detects a potential difference appearing at both ends of the voltage adjusting variable resistor 34 connected to the output side of the output-side smoothing circuit 30, and supplies a signal corresponding to the potential difference to the control circuit 26.
On the other hand, on the input side, the DC output from the smoothing circuit 20 is given to the control circuit 26. Then, based on such an input, the control circuit 26
A signal for N / OFF control is created and provided to the switching circuit 22 as described above. In addition,
Reference numeral 38 in the figure is a ground terminal.

A circuit as shown in FIG. 6 is composed of a plurality of electronic components. For example, the filter circuit 16 is a common choke coil, the rectifier circuits 18 and 28 are rectifying diodes, the smoothing circuits 20 and 30 are large-capacity electrolytic capacitors for smoothing, the switching circuit 22 is a power transistor, and the main electronic components. Components, and these electronic components are arranged on the same substrate.

[0005]

By the way, in the switching power supply device configured as described above, the life of the switching power supply device is significantly deteriorated by the influence of heat represented by an electrolytic capacitor. Electronic components "). In particular, in the switching power supply, the rectifier circuit 18,
Electronic components (hereinafter, referred to as “heat-generating electronic components”) that generate a large amount of heat, such as a diode at 28, a power transistor at the switching circuit 22, and a transformer 24,
In order to extend the life of the device,
It is an important problem to prevent performance degradation of the electronic component due to heat affected by heat generated from the heat-generating electronic component.

Here, in order to solve this problem, for example, it is conceivable to dispose the heat-affected electronic component at a position away from the heat-generating electronic component. However, the arrangement of each electronic component on the substrate becomes complicated. Also, there is a problem that the switching power supply device becomes large due to the enlargement of the substrate.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and suppresses the heat generated from a heat-generating electronic component from reaching a heat-affecting electronic component. It is an object of the present invention to extend the life of a switching power supply device provided therein.

[0008]

According to the present invention, there is provided a switching power supply device having a casing and first and second substrates disposed in the casing. Disposing the second substrate on one main surface side of the substrate and partitioning a space formed by the one main surface of the first substrate and the inner surface of the casing into first and second sub-spaces by the second substrate; In the first sub-space, the heat-generating electronic component is mounted on the one main surface of the first substrate, and in the second sub-space, on one main surface of the second substrate facing the sub-space. In addition, a heat-affected electronic component whose performance is degraded due to heat is mounted thereon.

According to the present invention, the space formed by one principal surface of the first substrate and the inner surface of the casing is defined by the second substrate.
And a second sub-space, wherein the second sub-space, which is a space for disposing the heat-affected electronic components, is thermally separated from the first sub-space, which is a space for disposing the heat-generating electronic components, and the heat generated from the heat-generating electronic components is second. Prevents heat affected electronic components in the subspace.

Further, there is a case where another heat-affected electronic component different from the heat-affected electronic component arranged in the second sub-space is arranged in the first sub-space. In such a case, By arranging this another heat-affected electronic component at a position deviating from the rising convection route of the heat generated from the heat-generating electronic component, the heat-affected electronic component can be placed in the first sub-space while being disposed. The heat influence on the heat-affected electronic component is suppressed (claim 2).

Further, the first side surface of the casing is provided with the first
A pair of openings are provided so as to face each other across the sub space,
The heat generated in the first sub-space by the airflow flowing between the pair of openings is configured to be exhausted to the outside of the device, thereby effectively suppressing heat from being trapped in the first sub-space. (Claim 3). In this case, when the second substrate is arranged along the direction of the airflow, a part of the airflow separates from the mainstream of the airflow, and even if the airflow tends to flow toward the second sub-space, the airflow becomes the mainstream on the other main surface of the second substrate. Returned, second
Part of the airflow can be prevented from flowing into the sub space (claim 4). Further, even when another heat-affected electronic component different from the heat-affected electronic component arranged in the second sub-space is arranged in the first sub-space, the other heat-affected electronic component is moved to the airflow. In the direction, the heat generated in the first sub-space is transferred to the downstream side in the direction opposite to the heat-affected electronic component by the airflow, so that the heat-affected electronic component is moved to the upstream side with respect to the heat-generating electronic component. 1
The heat effect on the heat-affected electronic component due to the heat-generating electronic component is suppressed while being arranged in the sub space (claim 5).

As a structure for attaching and detaching the first and second substrates to and from the casing, for example, a guide means is provided on the inner surface of the casing, and a substrate assembly (first unit) integrated along the guide means is provided. And the second substrate) may be configured to be attached and detached while guiding them. In this case, the first or second substrate is mounted on the casing by mounting the substrate on the casing.
A part of the substrate may be configured to be locked to the casing by being locked by a substrate locking means provided on the guide means (claim 6). Here, by configuring a part of the substrate to be press-fittable into the substrate locking means, the substrate assembly can be more firmly fixed to the casing by press-fitting the substrate (claim 7). ).

Further, each of the pair of openings may be constituted by, for example, a plurality of slit openings. In this case, there is a concern that the strength may decrease in a direction orthogonal to the longitudinal direction of the slit openings. However, the strength of the slit opening can be reinforced by bridging the guide means over these slit openings (claim 8). In other words, in such a configuration, the guide means functions not only as a guide function for the substrate but also as strength reinforcement of the slit opening.

Further, when a noise generating electronic component which can be a noise generating source is mounted on the first substrate, noise generated from the noise generating electronic component reaches an output terminal portion and is output to the output terminal portion. Noise components may be included. Therefore, by mounting the output terminal portion and an electronic component connected to the output terminal portion on the second substrate configured as described above, wiring from such an electronic component to the output terminal portion is performed. Since the distance is reduced and the output terminal is separated from the noise-generating electronic component, the output of the noise component from the output terminal is reduced.

[0015]

FIG. 1 is a perspective view showing one embodiment of a switching power supply according to the present invention, FIG. 2 is an exploded perspective view of the switching power supply of FIG. 1, and FIG. FIG. 2 is a sectional view taken along line AA of FIG. 1. Note that XYZ rectangular coordinate axes are shown in order to clarify the directional relationship with each drawing described later.

This switching power supply device is mounted on a din (DIN) rail 50 extending in the X direction on the bottom surface of a control unit (not shown), and converts AC supplied from the input terminal 10 into DC of a predetermined voltage. This is a device for supplying from the output terminal unit 12 to other devices provided in the control unit, and its circuit configuration is the same as that of FIG.
Those components are denoted by the same reference numerals and description thereof is omitted.

In this switching power supply device, as shown in FIG. 2, the casing 8 has a casing body 60 having an upper opening and a lid 70 provided to cover the opening.
When the cover 70 is attached to the upper end of the casing main body 60, a board assembly 90 obtained by integrating two boards 91 and 92 on which various electronic components are mounted as described later is provided. A storage space SP that can be stored is formed.

More specifically, the casing body 60 includes:
A peripheral wall portion 64 is erected upward from a base portion 62 on a lower side thereof to form a bottomed rectangular tube. Two locking holes 66 are provided near the upper ends of a pair of peripheral wall portions 64 a provided on the longitudinal direction (X direction) side of the din rail 50 among the four peripheral wall portions 64, respectively. The lid 70 is attached and fixed to the casing body 60 by locking the distal ends of the four locking pieces 72 extending downward into the corresponding locking holes 66.

As shown in FIG. 3, the peripheral wall 64b provided on the side (Y direction) orthogonal to the longitudinal direction (X direction) has an X section as shown in FIG. The slit openings 68 for heat radiation extending in the direction are provided at substantially equal intervals in the vertical direction (Z direction). Also,
In this embodiment, in each of the peripheral wall portions 64b, five reinforcing ribs 611 to 615 extending in the Z direction across all the slit openings 68 are attached side by side in the X direction, thereby reinforcing the strength of the peripheral wall portion 64b. I have. Of these, the reinforcing ribs 611 and 612 are arranged in the X direction at a distance Δ1 (FIG. 4) slightly larger than the thickness of the substrate 91.
For example, the interval Δ1 between the reinforcing ribs 611 and 612 with respect to the substrate 91 having a thickness of 1.6 mm is set to about 2 mm. For this reason, as shown in FIG. 2, a pair of left and right (Y direction) reinforcing ribs 611 and 612 function as guide means for the substrate 91, and the substrate 91 (the substrate assembly 90) is positioned and stored in the storage space SP. . As described above, in this embodiment, the reinforcing ribs 611 and 612 not only function as reinforcing the slit opening 68 but also function as guide means for the substrate. In particular, since the slit opening 68 has a heat dissipating function, its opening area should be set to be large, and compared to a case where the reinforcing ribs and the guide ribs are separately provided, a book that uses both the reinforcing and guiding ribs is provided. The embodiment can increase the opening area, and is advantageous in terms of the heat radiation effect. The reinforcing ribs 614 and 615 are configured to function as guide means, similarly to the reinforcing ribs 611 and 612.

The top 6 of the reinforcing ribs 611, 615
11a and 615a extend to a position slightly higher than the opening of the casing main body 60. When the substrate 91 is stored in the storage space SP along the guide means including the reinforcing ribs 611 and 612 as described above, The rear surface of the connected substrate 92 is configured to be locked by its tops 611a and 615a. As described above, in the present embodiment, the tops 611a, 61 of the reinforcing ribs 611, 615 are used.
The board assembly 90 is supported in the casing 80 by 5a.

As described above, the guide means (reinforcing ribs 61)
1, 612), the substrate assembly 90 is guided to the storage space SP, and merely the tops 611 of the reinforcing ribs 611, 615.
If the substrate 92 is only supported from the back side by the a and 615a, the rattling of the substrate assembly 90 occurs in the casing 80, and the vibrations and shocks cause cracks or the like in the solder portion on the substrate, and as a result, the electronic component Connection failure or disconnection may occur. Therefore, in this embodiment, in order to solve this problem, the reinforcing rib 61 is used.
At the lowermost position of 1,612, a rattling preventing rib for preventing substrate rattling is provided.

FIG. 4 is a partially enlarged sectional view showing the structure of the backlash preventing rib. In this embodiment, as shown in the figure, substantially hemispherical rattling preventing ribs 611b, 611 are provided on reinforcing ribs 611, 612 so as to face each other.
2b are protruded respectively. The distance Δ2 between the protruding portions of the backlash preventing ribs 611b and 612b is
1 is slightly smaller than the thickness of the substrate 91 along the guide means (reinforcing ribs 611, 612) as described above.
Is moved to the lower position, and the substrate assembly 90 is moved to the casing 8.
0, the lower end 911 of the substrate 91 is press-fitted between the anti-rattle ribs 611b and 612b at the final stage of the substrate storage, and the substrate 91 is sandwiched in the thickness direction (X direction). Is firmly held in the thickness direction of the substrate. Even if the distance Δ2 between the ribs 611b and 612b is set to the same dimension as the thickness of the substrate 91, rattling of the substrate with respect to the casing 80 can be prevented.

Further, in the present embodiment, at the same height position as the backlash preventing ribs 611b and 612b,
Between the reinforcing ribs 611 and 612, a pair of hemispherical rattling preventing ribs 619 are protruded toward the storage space SP so as to face each other.
0 is stored in the storage space SP of the casing 80, the lower end 911 (FIG. 2) of the substrate 91 is press-fitted between the anti-rattle ribs 619 and 619 in the final stage of the substrate storage, and the substrate 91 is moved in the width direction. (Y direction) and is firmly held in the substrate width direction.

As described above, in the present embodiment, the backlash prevention ribs 611b and 612b are provided to hold the substrate 91 in the thickness direction and to prevent the backlash prevention ribs 619 and 611.
19 is provided so as to hold the board 91 in the width direction, so that rattling of the board assembly 90 in the casing 80 can be prevented, and defects such as cracks and breaks in the solder portion can be effectively prevented. Can be prevented.

In this embodiment, in the substrate thickness direction (X
Direction) to prevent the backlash of the substrate.
1 and 612, the backlash prevention ribs 611b,
Although 612b is provided, it may be provided on either one. The backlash preventing ribs 611b, 61
Although 2b is provided as a spot at the lowermost position of the reinforcing ribs 611, 612, it may be provided continuously in the height direction (Z direction) of the reinforcing ribs 611, 612. The shape of the backlash preventing ribs 611b and 612b is not limited to a hemispherical shape, and is not particularly limited as long as the substrate 91 can be press-fitted.

The deformation of the ribs 611b and 612b in the thickness direction of the substrate can be applied to the rib 619 in the width direction of the substrate. That is, in the width direction (Y direction) of the substrate, it is only necessary to provide the backlash prevention rib 619 on only one side, and the backlash prevention rib 619 is continuous in the height direction (Z direction) of the reinforcing ribs 611 and 612. The shape of the backlash preventing rib 619 is not particularly limited to a hemispherical shape as long as the substrate 91 can be press-fitted.

Returning to FIG. 1 and FIG. 2, the characteristics of the casing 80 according to the present embodiment employing the finger protection structure will be described. In this embodiment, as shown in FIG.
The output terminal section 12 is mounted on the other side while the 0 and ground terminal sections 38 are mounted, and each terminal is soldered to the substrate 92 at two locations. In addition, corresponding to each terminal attached to the substrate 92, an opening 74 for drawing the wiring into the terminal portion is opened in the side surface portion of the lid 70, and a screwing tool can be inserted. An opening 76 is formed in such a manner that a human finger cannot be inserted, and the distal end of the wire inserted into the terminal portion through the opening 74 can be fixed to the terminal. As described above, in this embodiment, the following effects are obtained by adopting the finger protection structure in the switching power supply device. That is, it is possible to effectively prevent the worker from directly touching the terminal. In addition, the terminal mounting structure can be simplified. Further, the connection between the terminal and the substrate is strengthened, so that the occurrence of cracks in the solder portion due to vibration or impact can be prevented, and it is possible to cope with a large current.

Further, the input terminal section 10 and the output terminal section 12
In addition, the grounding terminal 38 supports the lid 70 from the inner bottom surface side, and the strength of the lid 70 is reinforced. For this reason, a reinforcing structure such as a rib used for reinforcement in the conventional device becomes unnecessary, and as a result, the cover 70
The internal accommodation space (second sub-space SSP2) is increased, and more and larger electronic components can be mounted on the substrate 92.

In the above description, the configuration of the casing of the switching power supply has been mainly described in detail. Next, the configuration inside the device will be described in detail.

In the switching power supply according to this embodiment, as described above, one substrate assembly 90 is formed by connecting the two substrates 91 and 92 to each other, and this is stored in the storage space SP of the casing 80. Have been. As shown in FIG. 2, the substrate 91 has a shape in which one end 912 is finished in a convex shape, and the filter circuit 16 is formed on the surface (one main surface) of the substrate 91. 161 and the common choke coil 162, the diode constituting the input-side rectifier circuit 18, and the electrolytic capacitor 20 constituting the input-side smoothing circuit 20
1. Electronic components such as a power transistor forming the switching circuit 22 and a heat sink 221, a transformer 24, and a diode forming the output side rectifier circuit 28 are mounted. On the other hand, the substrate 92 has a convex end 912 of the substrate 91.
A concave portion 921 is formed on the substrate surface (one main surface) in addition to the input terminal portion 10, the grounding terminal portion 38, and the output terminal portion 12, and is directly connected to the output terminal portion 12. Electrolytic capacitors 301 and 302 and a coil 303 constituting the output side smoothing circuit 30 are mounted.

When the substrate 91 is in an upright position in the vertical direction (Z direction) with the convex end 912 positioned upward, the concave portion 921 is engaged with the convex end 912 of the substrate 91. In this state, the substrate 92 is in a substantially horizontal posture, and the two substrates 91 and 92 are mechanically and electrically connected by a connecting member (not shown) in such a substrate posture to form a substrate assembly 90. You. The substrate assembly 90 integrated in this manner is configured such that the rear surface of the substrate 91 is covered with the casing 80.
Is housed in the housing space SP of the casing 80 as described above, while being kept close to the inner surface of the housing 80.

FIG. 5 is a diagram showing a state of the board assembly housed in the housing space of the casing. For convenience of explanation, FIG.
The illustration of the casing 80 is omitted, and the storage space S is indicated by a two-dot chain line.
P is virtually shown. When housed in the casing 80, the surface (one main surface) of the substrate 91 and the casing 80
And a space substantially coincident with the storage space SP is formed with the inner surface of the substrate 9.
2 separates two subspaces SSP1 and SSP2. That is, the first sub-space SSP1 is a space surrounded by the inner surface of the casing 80, the surface (one main surface) of the substrate 91, and the back surface (the other main surface) of the substrate 92, as shown in FIG. The second sub space SSP2 is a space surrounded by the inner surface of the casing 80, the surface (one main surface) of the convex end 912 of the substrate 91, and the surface (one main surface) of the substrate 92.

In this embodiment, the electrolytic capacitors 301 and 302 corresponding to the heat-affected electronic components are arranged in the second sub space SSP2, while the rectifying diode, the switching power transistor and the transformer corresponding to the heat-generating electronic components are provided. 24 etc. are all in the first subspace SSP1
, The substrate 92 functions as a heat shielding plate,
The heat in the first sub space SSP1 is prevented from reaching the second sub space SSP2. A plurality of slit openings 68 are formed in the peripheral wall 64b of the casing 80,
For example, as shown by a solid arrow in FIG. 5, when air flows in from the outside of the apparatus through the slit opening 68 (FIG. 3) on one side, heat trapped in the first sub-space SSP1 by the air flow is applied to the other slit. Although the airflow is carried out of the apparatus through the opening 68, a part of the airflow separates from the main flow in the first subspace SSP <b> 1 and tries to flow into the second subspace SSP <b> 2. Then, it is returned to the main stream and exhausted to the outside of the apparatus through the slit opening 68. Therefore, in the present embodiment, the second sub space SSP2 is thermally separated from the first sub space SSP1, and the inside of the second sub space SSP2 can be kept at a low temperature.
The deterioration of the performance of the electrolytic capacitors 301 and 302 can be prevented, and the life of the switching power supply can be extended.

In this embodiment, the input-side smoothing circuit 2
0 in the first sub space SS
Although placed at P1, ideally an electrolytic capacitor 20
It is also desirable to arrange 1 in the second subspace SSP2. However, considering wiring and storage space,
There is a case where it is generally advantageous to dispose it in the first sub space SSP1 as in the present embodiment. In such a case, the electrolytic capacitor disposed in the first sub space SSP1 is the transformer 2
It is not necessarily not affected by the heat generated from the heat-generating electronic components such as 4 and the diode, but it is possible to minimize the thermal effect by devising the position of the electrolytic capacitor 201 with respect to the heat-generating electronic components. Can be. That is, although the heat generated in the first sub space SSP1 tends to rise upward, in this embodiment, the electrolytic capacitor 201 is arranged at a position deviated from the rising convection route of the heat (broken arrow in the figure). The influence of heat from the heat-generating electronic components is suppressed. Further, in the air flow (solid arrow in the figure) flowing in the first sub space SSP1, the electrolytic capacitor 201 is disposed so as to be located on the upstream side with respect to the heat-generating electronic components. The heat generated from the heat-generating electronic components is relatively cold and is carried in the direction of the air current in the direction opposite to the electrolytic capacitor 201.

In the above embodiment, the first sub space S
While electronic components such as power transistors and transformers, which are noise sources, are concentrated on SP1, the second subspace S
Since an electronic component (such as an electronic component constituting an output-side smoothing circuit) directly connected to the output terminal unit 12 is arranged in SP2, the distance from the electronic component to the output terminal unit 12 is reduced, and noise is generated. By separating the source from the output terminal unit, it is possible to effectively prevent the direct current output from the output terminal unit 12 from including noise from a noise generation source.

Note that the present invention is not limited to the above-described embodiment, and various changes other than those described above can be made without departing from the gist of the present invention. For example, the application object of the present invention is not limited to a switching power supply device of a type that is vertically mounted on a din rail 50 provided on a bottom portion of the control unit, but is provided on a side portion of the control unit. The base portion 62 of the casing 80 can be mounted almost horizontally on the din rail that has been
The present invention can also be applied to a switching power supply of a type in which the screw is directly screwed to a control unit or the like via a mounting hole formed in the power supply.

In the above embodiment, the case where the present invention is applied to the switching power supply device having the circuit configuration of FIG. 6 has been described. However, the present invention is not limited to the switching power supply device of FIG. Instead, the present invention can be applied to all switching power supply devices in which heat-generating electronic components and heat-affected electronic components are arranged in the same casing.

In the above embodiment, the storage space SP is divided into two first and second sub-spaces SSP1 and SSP2 by combining the second substrate 92 with the first substrate 91.
Although the electrolytic capacitors 301 and 302 corresponding to the heat-affected electronic components are arranged in the second sub space SSP2, another substrate is added so that the heat-affected electronic components are thermally separated from the heat-generating electronic components. You may. For example, by connecting this substrate to the second substrate 92 so that this another substrate is located in the first sub-space SSP1,
1 is further divided into two parts, one of which is provided with a rectifying diode, a switching power transistor, a transformer 24, and the like corresponding to heat-generating electronic components, and the other is provided with heat-affecting electronic components. It has the same function as the upper second substrate, and the same effect as the above embodiment can be obtained. In this case, the reinforcing ribs 614 and 615 function as guide means for the added substrate, and the rattling preventing rib 619 is provided between the reinforcing ribs 614 and 615, whereby the substrate assembly constituted by the three substrates is provided. It can be fixed firmly to the casing.

In addition, instead of connecting the another substrate to the second substrate 92, the first sub space SSP1 is further divided into two by connecting to the first substrate 91, one of which corresponds to a heat-generating electronic component. The same effect as described above can be obtained by arranging a rectifying diode, a switching power transistor, a transformer 24, and the like, and arranging a heat-affecting electronic component on the other side.

Further, in the above embodiment, the first substrate 91
The storage space SP is partitioned into two subspaces by connecting the second substrate 92 to the surface of the second substrate 92 in an inverted posture, but the posture of the second substrate 92 with respect to the first substrate 91 is not particularly limited. For example, a second substrate 92 is disposed substantially parallel to the first substrate 91 between one main surface of the first substrate 91 and the inner surface of the casing, and the second substrate is formed by the one main surface of the first substrate and the inner surface of the casing. May be divided into two spaces.

[0041]

As described above, according to the first aspect of the present invention, the second substrate is disposed on the one main surface side of the first substrate and formed by the one main surface of the first substrate and the inner surface of the casing. Space divided by the second substrate into first and second sub-spaces,
In the first sub-space, the heat-generating electronic component is mounted on one main surface of the first substrate, and in the second sub-space, on one main surface of the second substrate facing the sub-space, heat is applied. Since the heat-affected electronic components that deteriorate in performance are configured to be mounted, the second sub-space in which the heat-affected electronic components are arranged can be thermally separated from the first sub-space in which the heat-generating electronic components are arranged. It is possible to prevent heat generated from the electronic component from reaching the heat-affected electronic component in the second subspace, suppress performance degradation of the heat-affected electronic component, and extend the life of the switching power supply device.

According to the second aspect of the present invention, another heat-affected electronic component different from the heat-affected electronic component arranged in the second sub-space is arranged in the first sub-space. However, since the other heat-affected electronic component is arranged at a position deviating from the convection route of rising heat generated from the heat-generating electronic component, the heat effect of the heat-generated electronic component is suppressed, and It is possible to suppress the performance deterioration and suppress the performance deterioration of the heat-affected electronic component, and more particularly, to prolong the service life of the switching power supply device.

According to the third aspect of the present invention, a pair of openings are provided on the side surface of the casing so as to oppose each other with the first sub space interposed therebetween. Since the heat generated in the first sub-space is configured to be exhausted to the outside of the device, it is possible to effectively suppress the heat from being trapped in the first sub-space and suppress the temperature rise in the first sub-space. Therefore, the heat effect on the heat-affected electronic component can be suppressed.

According to the fourth aspect of the present invention, since the second substrate is arranged along the direction of the air flow, a part of the air flow is separated from the main flow of the air flow and flows toward the second sub space. Even if you try to insert it, it will return to the main flow on the second substrate,
It is possible to prevent a part of the airflow from flowing into the second sub space, and to suppress the performance deterioration of the heat-affected electronic components arranged in the second sub space.

According to the fifth aspect of the present invention, another heat-affected electronic component different from the heat-affected electronic component disposed in the second subspace is placed upstream of the heat-generating electronic component in the direction of airflow. Side, the heat generated in the first sub-space can be carried by airflow to the downstream side in the opposite direction to the heat-affected electronic component, and the heat from the heat-generating electronic component is separated from the heat-affected electronic component. It is possible to suppress the influence on the components, and to suppress the performance deterioration of the heat-affected electronic component.

According to the sixth aspect of the present invention, when the substrate is mounted on the casing, a part of the first or second substrate is locked by the substrate locking means provided on the guide means. With such a configuration, the substrate is fixed to the casing, and rattling of the substrate can be effectively prevented.

According to the seventh aspect of the present invention, since a part of the substrate can be press-fitted into the substrate locking means, the substrate is more firmly fixed to the casing by the press-fitting of the substrate. can do.

According to the eighth aspect of the present invention, the guide means spans the slit opening forming the opening, whereby the guide means also functions to reinforce the slit opening. The strength of the part can be increased.

According to the ninth aspect of the present invention, the first substrate is mounted with a noise generating electronic component which can be a noise generation source, while the second substrate is connected to the output terminal and the output terminal. The wiring distance from such an electronic component to the output terminal portion is shortened, and the output terminal portion is separated from the noise-generating electronic component and the noise from the output terminal portion is mounted. The output of the component can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one embodiment of a switching power supply device according to the present invention.

FIG. 2 is an exploded perspective view of the switching power supply device of FIG.

FIG. 3 is a sectional view taken along line AA of FIG. 1;

FIG. 4 is a partially enlarged cross-sectional view showing a configuration of a backlash preventing rib.

FIG. 5 is a diagram illustrating a stored state of a board assembly stored in a storage space of a casing.

FIG. 6 is a diagram illustrating an example of an internal circuit configuration of the switching power supply device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Input terminal part 12 ... Output terminal part 24 ... Transformer (heating electronic component) 30 ... Output side smoothing circuit 38 ... Grounding terminal part 60 ... Casing main body 62 ... Base part 64b ... Peripheral wall part 68 ... Slit opening (opening part) 70 ... lid 80 ... casing 90 ... board assembly 91 ... (first) board 92 ... (second) board 201 ... electrolytic capacitor (another heat-affected electronic component) 301, 302 ... electrolytic capacitor (heat-affected electronic component) 611, 612: reinforcing ribs (guide means) 611b, 612b, 619: rattling preventing ribs (board locking means) SP: storage space SSP1: first subspace SSP2: second subspace

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kimihiro Ito 1-7-131 Nishimiyahara, Yodogawa-ku, Osaka-shi Inside Izumi Electric Co., Ltd. (72) Inventor Toshiharu Matsumoto 1-7-131 Nishimiyahara, Yodogawa-ku, Osaka-izumi Electric Co., Ltd. F-term (reference) 5E322 BA01 BA05 CA06

Claims (9)

[Claims] 1. A switching power supply device comprising: a casing; and first and second substrates disposed in the casing, wherein the second substrate is disposed on one principal surface side of the first substrate, and A space formed by one main surface of one substrate and the inner surface of the casing is partitioned by the second substrate into first and second subspaces. In the first subspace, the heat-generating electronic component is placed in the first subspace.
While being mounted on the one main surface of the substrate, a heat-affected electronic component whose performance is degraded by heat is mounted on one main surface of the second substrate facing the sub-space in the second sub-space. A switching power supply device characterized by being performed. 2. A heat-affected electronic component different from the heat-affected electronic component arranged in the second sub-space in the first sub-space, wherein the heat-affected electronic component is the heat-generating electronic component. 2. The switching power supply device according to claim 1, wherein the switching power supply device is attached to the first substrate so as to be located at a position deviated from a convection route of rising heat generated from the first substrate. 3. A pair of openings are provided in a side surface of the casing so as to face each other across the first sub space, and an air flow flowing between the pair of openings in the first sub space. 3. The switching power supply device according to claim 1, wherein the generated heat can be exhausted to the outside of the device. 4. The switching power supply according to claim 3, wherein the second substrate is arranged along a direction of the airflow. 5. A heat-affected electronic component different from the heat-affected electronic component disposed in the second sub-space in the first sub-space, wherein the heat-affected electronic component is disposed in the direction of the airflow. The switching power supply device according to claim 3, wherein the switching power supply device is attached to the first substrate so as to be located on an upstream side with respect to the heat-generating electronic component. 6. The first and second substrates are detachably mounted on the casing while being guided by guide means provided on the inner surface of the casing in an assembled state in which the first and second substrates are integrated with each other. A part of the first or second substrate is locked by substrate locking means provided on the guide means and fixed to the casing by mounting the substrate on the casing. 6. The switching power supply device according to any one of 5. 7. The switching power supply device according to claim 6, wherein a part of the substrate is press-fittable into the substrate locking means, and is fixed to the casing by press-fitting the substrate. 8. The switching power supply device according to claim 6, wherein each of the pair of openings is constituted by a plurality of slit openings, and the guide means is bridged over the plurality of slit openings. 9. A noise generating electronic component which can be a source of noise is mounted on the first substrate, while an output terminal portion and an electronic component connected to the output terminal portion are mounted on the second substrate. The switching power supply device according to any one of claims 1 to 8, which is mounted.