JPH0241876Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field This invention relates to a small power supply device in which a main circuit and a control circuit are mounted on one or two printed circuit boards.

(b) Prior Art This type of power supply device rectifies commercial power, switches it at high frequency, and then rectifies it again via a high frequency transformer before outputting it.
The circuit consists of a main circuit including a switching circuit and a high-frequency transformer, and a control circuit that detects the output current or output voltage and controls the switching transistors on the primary side to turn on and off based on the detected value. Such a power supply device does not require a small transformer or a large choke, so it has the advantage that the entire device, especially the main circuit, can be made smaller.

(c) Problems to be solved by the invention In general, the power supply devices described above have the advantage of being able to miniaturize the entire device, but they use a large number of parts and the circuitry is complex, so it is difficult to use after assembly. It is necessary to check the circuit and perform maintenance and inspection during use. However, in conventional power supplies, once assembled, there are a large number of wires connecting the parts, making it extremely difficult to perform circuit checks and maintenance inspections, and even if the main circuit and control circuit are mounted on the board. , because the structure was not such that the back side of all the circuits was easily exposed.
As expected, circuit checks and maintenance inspections were difficult.

The purpose of this invention is to simplify the overall structure of the device, and to make it easier to conduct circuit checks and maintenance by removing the cover and exposing the back side of the board on which the main circuit and control circuit are mounted. The object of the present invention is to provide an extremely simple power supply device.

(d) Means for solving the problem This invention consists of a front plate with an operation switch, etc., a back plate, a plurality of crosspieces to which the front plate and the back plate are fixed at both ends, and the crosspieces. fixed,
It is characterized by comprising a printed circuit board on which a main circuit and a control circuit are mounted, and a ceiling plate and an underframe that cover the upper and lower parts of the printed circuit board.

(e) Effect In the power supply device according to this invention, the main circuit and the control circuit are mounted on a printed circuit board, and the printed circuit board is fixed to a crosspiece between the front plate and the back plate. Therefore, the mounting structure of the printed circuit board becomes strong, and since it is fixed to the crosspiece, both the front and back surfaces of the printed circuit board are exposed. Therefore, circuit checks and maintenance inspections can be easily performed by removing the ceiling board and underframe that cover the power supply unit.

(f) Embodiment FIG. 1 shows an assembly diagram of a power supply device which is an embodiment of this invention. In the figure, 1 is a front plate provided with operation switches and the like, and 2 is a back plate. The front plate 1 and the back plate 2 are fixed to both ends of two crosspieces 3 and 4, respectively. Since the crosspieces 3 and 4 are located on both sides of the front plate 1 and the back plate 2, a space is formed between the crosspieces 3 and 4. The front plate 1 is provided with a power switch 10, an output voltage adjustment switch 11, etc., and further has an air inflow hole 12 formed therein. Air outflow holes 20 are formed in the back plate 2.

The printed circuit board 5 is formed with main circuits such as a high frequency switching circuit and a high frequency transformer, and a control circuit that generates switching control pulses and the like. A heat dissipation fin 6 is erected approximately at the center of the printed circuit board 5. The printed circuit board 5 is divided into left and right regions 50 and 51 by the heat dissipation fins 6. Main circuits such as switching transistors and high frequency transformers with large power consumption are mounted in the region 50, and main circuits such as switching transistors and high frequency transformers with large power consumption are mounted in the region 50. A control circuit with low power consumption is implemented. Three screw holes 54 and 55 are formed at both left and right ends of the printed circuit board 5, respectively. The printed circuit board 5 is placed on the crosspieces 3 and 4, and the screw holes 3 formed in each crosspiece 3 and 4 are inserted into the printed circuit board 5.
It is fixed with screws while aligned at 0 and 40. Further, a fan 7 is attached to the back plate 3 at the position of the air outflow hole 20.

FIG. 2 shows a state in which the printed circuit board 5 to which the radiation fins 6 are attached as described above is integrated with the crosspieces 3 and 4. As shown in the figure, the heat radiation fin 6 separates the main circuit consisting of heat generating components from the control circuit which does not generate much heat, and by driving the heat radiation fan 7, a ventilation duct is formed on the main circuit side. . That is, air flows in from the air inlet 12 formed in the front plate 1, passes through the ventilation duct formed between the front plate 1, the back plate 2, the heat dissipation fins 6, and the ceiling plate (described later), and flows into the fan. 7, it flows out to the outside. At this time, the heat generated in the region 50 of the printed circuit board 5 is exhausted to the outside by the air passing through the ventilation duct.

The ceiling plate 8 is a cover that covers the upper part of the assembled part as described above, and the base plate 9 is a cover that covers the lower part of the assembled part. These ceiling plate 8 and base plate 9 are fixed to mounting pieces formed on the front plate 1 and the back plate 2 with screws.

With the above configuration, the entire device is assembled by fixing the front plate 1 and back plate 2 to both ends of the crosspieces 3 and 4 with screws, and then attaching the printed circuit board 5 on which the heat dissipation fins 6 are attached and the components are mounted. Fix screws to crosspieces 3 and 4. Next, the fan 7 is also attached to the back plate 2, and finally the ceiling plate 8 and base plate 9 are fixed with screws.

When performing a circuit check, before attaching the base plate 9, the terminals of the measuring device are brought into contact with desired circuit sections from the back side of the device. At this time, the lower part of the printed circuit board 5 is completely open, so that the terminals of the measuring device can be easily brought into contact with it. When performing maintenance and inspection of the power supply device, the base plate 9 is similarly removed. Since the fan 7 is driven when the device is in use, the printed circuit board 5
The heat generated from the heat generating components mounted in the left side area 50 is efficiently dissipated to the outside. In this case, since the left side area 50 and the right side area 51 of the printed circuit board 5 are separated by the heat radiation fins 6, the heat from the heat generating section does not reach the control circuit section. Furthermore, since the inside of the device is completely sealed by the ceiling plate 8 and the base plate 9, it is also possible to prevent dust from entering the inside from the outside. In particular, if the height of the heat dissipation fin 6 is made the same as the height of the front plate 1 and the back plate 2, dust etc. that flowed in from the air inflow hole 12 will be removed from the right side of the heat dissipation fin 6, that is, the printed circuit board on which the control circuit is mounted. Since the dust does not flow into the region 51, the dust-proofing effect on the control circuit can be significantly improved.

(g) Effects of the invention According to this invention, since the printed circuit board is fixed to a plurality of crosspieces, the front and back surfaces of the printed circuit board are exposed. This has the advantage of making circuit checks extremely easy. In addition, since the front plate and back plate are fixed to multiple crosspieces, the printed circuit board is fixed to the crosspieces, and the top and bottom are covered by the ceiling plate and base plate, the entire structure can be improved by using the crosspieces. This has the advantage that the structure is strong and simple, making it extremely easy to handle.

[Brief explanation of the drawing]

FIG. 1 is an assembled diagram of a power supply device that is an embodiment of this invention, and FIG. 2 is a diagram showing a state in the middle of assembly. 1... Front plate, 2... Back plate, 3, 4... Crosspiece,
5... Printed circuit board, 6... Heat dissipation fin, 7...
Juan, 8...Ceiling board, 9...Bedboard.

Claims (1)

[Scope of utility model registration request] A front plate with operation switches, etc., a back plate, a plurality of crosspieces to which the front plate and the back plate are fixed at both ends, and a printed circuit board fixed to the crosspieces and on which a main circuit and a control circuit are mounted. , a ceiling plate that covers the upper and lower parts of these, and a base frame.