JPS6287889A - Mounting structure of power unit for copier, etc. - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a power supply device mounting structure used in copying machines, facsimile machines, etc. The present invention relates to improvements in a power supply device mounting structure that is effective for power supply devices.

[Prior Art] Conventionally, a power supply device used in a copying machine, etc. is equipped with various power supply elements on a board, but the power supply elements include a heat generating element such as a power transistor. Therefore, a heat sink is attached to each heat generating element to release the heat from the heat generating element into the air. This type of power supply device is mounted on the aircraft frame along with various other devices.

[Problems to be Solved by the Invention] However, when the machine frame itself is made smaller in response to the demand for miniaturization of copying machines, etc., the mounting space for the power supply device usually becomes narrow, so it is necessary to The heat emitted inside the device tends to accumulate around the power supply, causing the surrounding air temperature to rise more than necessary. For this reason, it is necessary to use materials with high heat resistance for each power supply element including the heating elements mentioned above, and the
A problem arises in that the cost of the Fi source element increases unnecessarily.

Furthermore, as mentioned above, there is almost no air convection around the power supply, so there is a risk that toner and dust floating within the aircraft frame may adhere to the power supply elements and circuit boards. , problems arise in that each power supply element deteriorates early and wiring on the board is short-circuited.

In order to solve this problem, it is possible to install ventilation louvers on the sides of the aircraft frame, and use the airflow from these louvers to create forced convection within the aircraft frame. However, even with this type, if a finger or the like is allowed to enter the louver portion, it may pose a safety problem.

In addition, since the above power supply unit is a somewhat heavy item, in order to reliably support it on the aircraft frame, it is necessary to increase the surface rigidity of the aircraft frame by increasing its thickness. Another problem has arisen in that the weight of the copying machine increases.

[Means for Solving the Problems] The present invention has been made in view of the above-mentioned problems, and it is possible to ensure the support strength for the power supply device while reducing the weight of the aircraft frame, and also to ensure safety. In addition to increasing the cooling efficiency of the power supply unit to the extent that it does not interfere with the countermeasures, the power supply 8!
The present invention provides a mounting structure for a power supply device of a copying machine, etc., which suppresses adhesion of toner and dust to the device.

That is, the present invention provides a structure in which a power supply device is disposed on the body frame of a copying machine, etc., by forming an emboss on the body frame corresponding to the location where the power supply device is disposed, thereby injecting air into the lower part of the body frame. In addition to forming a flow path, a ventilation path is formed that communicates the air flow path with the vicinity of the heat generating part of the power supply device.

In such technical means, the power supply device can be either low-voltage or high-voltage, and its specific configuration may be one in which a power supply element is simply mounted on a board, or one equipped with a power supply element. A heat dissipation plate is fixedly provided on the board, and the board is fixed to the fuselage frame via the heat dissipation plate.A board equipped with a power supply element is held by a power supply frame, and the board is fixed to the aircraft frame via the heat dissipation plate. The design may be modified as appropriate, such as by fixing the board to the aircraft frame. In addition, the shape and size of the emboss mentioned above may be modified as appropriate as long as an air flow path can be secured at the bottom of the fuselage frame. It is desirable to guide cold air around the power supply unit, and it is necessary to design the opening position of the emboss so that hot air such as fuser cooling air discharged from the copying machine does not enter the emboss and the airflow path. It is. Further, the shape, number, arrangement, etc. of the air passages may be changed as appropriate, but it is necessary to design them so that at least the air from the air flow passages can be guided to the vicinity of the heat generating part of the power supply device. In this case, if the heat generating part of the power supply unit faces the embossed part, it is sufficient to provide a ventilation path only in the embossed part, but if the heat generating part of the power supply unit does not face the embossed part, then It is necessary to provide a ventilation path on the power supply device side corresponding to the ventilation path in the embossed portion. for example,
In the type where the board is attached via the heat dissipation plate, a ventilation passage is provided in the heat dissipation plate part corresponding to the ventilation passage in the embossed part, and in the type in which the board is attached through the power supply frame, there is a ventilation passage in the embossed part on the power supply frame and the board. It is like providing ventilation passages corresponding to the respective passages.

[Function] According to the above-mentioned technical means, an air flow passage is formed in the lower part of the body frame of a copying machine, etc., and a ventilation passage is formed that communicates this air flow passage with the vicinity of the heat generating part of the power supply device. Therefore, due to the suction power of the cooling fan, etc. installed inside the aircraft frame, the outside air outside the aircraft frame is guided to the vicinity of the heat generating part of the power supply device through the air flow path and the ventilation path, and the air is drawn to the vicinity of the heat generating part of the power supply device. Forced upward convection is formed. Therefore, high-temperature air does not stay near the heat generating portion of the power supply device, and the situation where floating toner and dust within the body frame approach the power supply device portion is also effectively avoided.

In addition, since the fuselage frame corresponding to the location where the power supply device is installed is formed as an embossment, the surface rigidity of this fuselage frame portion is ensured sufficiently without increasing the thickness of the fuselage frame, and it supports the power supply device. The intensity can be set too high.

[Embodiments] Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings.

In the embodiment shown in FIG. 1, a single embossment 2 is formed on the bottom of a body frame 1 of a copying machine or the like, facing upward and with both ends opening 1'! ! There is one stage, and this emboss 2
A lower region of the fuselage frame 1 defined by the installation surface 3 of the fuselage frame 1 is formed as an airflow passage 4.

A power supply device P is disposed on the top surface of the embossing 2.

In this embodiment, the power supply P is a low voltage type, so its basic configuration is as shown in FIGS. 2 and 3.
A power distribution board 10 is equipped with various power supply elements, such as an input connector 11, a fuse 12 for overcurrent prevention, a triac 13, and an electrolytic capacitor 1 for forming a voltage on the negative side.
4. The basic elements of the - secondary side transformer 15, the secondary side transformer 16, the secondary side electrolytic capacitor 17 that accumulates the voltage from the secondary side transformer 16, and the output connector 18 cap, as well as the power 1 It is equipped with heating elements such as a helangistor 19, a large capacity diode 20, and a three-terminal regulator 21 for preventing voltage change FJJ. In this embodiment, the power transistor 19,
Heat generating elements such as a large capacity diode 20 and a three-terminal regulator 21 are installed near the bottom of the substrate 10 -U
J) i. A flat heat dissipating plate 30 with high thermal conductivity is attached to the lower end of the substrate 10 at right angles to the substrate 10 with fasteners 31 such as screws, and each of the heating elements is attached to the heat dissipating plate. It is held by a holder 32 fixed to 30 and is placed in contact with the heat dissipation plate 30 .

Further, mounting holes 22 are provided on both sides of the upper part of the substrate 10, and mounting holes 33 are provided on both sides of the opposite end of the substrate 10 of the heat dissipation plate 30. A plurality of ventilation holes 34 are provided in a portion of the heat dissipation plate 30 corresponding to the transformers 15 and 16.

In addition, the installation part of the power supply device P is as shown in Fig. 4.
A bracket 41 is installed upright on the widthwise negative side of the embossed portion 2 of the fuselage frame 1, and this installation is performed using the bracket 41.
Attachment holes 42 are provided on both sides of the upper part of the embossing plate 1, and attachment holes 43 and ventilation holes 44 are provided at the top of the embossing plate 30 in correspondence with the attachment holes 33 and ventilation holes 34 of the heat dissipation plate 30.

Therefore, when installing the power supply device in the above installation,
As shown in FIG. 5, the embossment 2 of the aircraft frame 1
After inserting the power supply device into the section from above and arranging it in a vertical position, the fastening tool 23 such as a clip that has been previously locked into the mounting hole 22 of the board 10 is fixed to the mounting hole 42 on the bracket 41 side. After that, fasteners such as screws may be attached to each of the mounting holes 33 and 43 of the heat dissipation plate 30 and the embossing 2.

In such a power supply installation structure, the heat dissipation plate 30 is directly attached to the fuselage frame 1 as a mounting member, so that the heat from each heating element on the board 10 is transferred to the fuselage frame 1 via the heat dissipation plate 30. According to legend), the fuselage frame 1. It is dispersed and released into the air from all over the area. Therefore, the heat from each heating element is no longer concentrated and emitted into the air around the power supply device, and the rise in air temperature around the power supply device can be suppressed to some extent. However, the heat from each heating element is gradually released into the air, and moreover, each transformer 15
．． Since the transformers 15 and 16 are not in direct contact with the heat dissipation plate 30, the heat from each transformer 15 and 16 is also released into the air. Therefore, heat gradually accumulates near the heat generating part of the power supply unit. Due to the suction force of a vacuum cleaner (not shown), the outside air outside the fuselage frame 1 is
As shown by arrow A in FIG. 5, a convection current of air directed upward is forced to be formed through the air flow path 4 and each ventilation hole 44, 34 near the heat generating part of the power supply device. . Therefore, the heat near the heat generating part of the power supply device is carried by the convection and sent out to parts other than the vicinity of the power supply device, and an increase in the air temperature around the power supply device is reliably avoided.

In addition, in this embodiment, upward air convection occurs around the power supply device, so even if toner or dust is floating inside the machine frame 1, the toner etc. will not approach the power supply device. This effectively avoids situations in which toner or the like adheres to the power supply elements, causing early deterioration of each element, or toner or the like adheres to the wiring portion of the board 10, causing a wiring short-circuit accident. The situation will definitely be avoided.

Furthermore, in this embodiment, the fuselage frame 1 corresponding to the location where the power supply device is installed is provided with an embossment 2.
The surface rigidity of the fuselage frame 1 in this part is ensured to be high without particularly increasing the plate thickness of the fuselage frame 1. Therefore, even if a power supply device that is a certain amount of weight is installed, there is no risk that the body frame 1 will be deformed, and the power supply device can be stably installed.

Furthermore, in this embodiment, the heat from each heating element is transmitted to the fuselage frame 1 side via the heat dissipation plate 30 and radiated from the entire area of the fuselage frame 1. There is no need to attach a heat sink, and the number of parts of the power supply device can be reduced accordingly, and the power supply device itself can be made smaller by 1J.

The shape of the embossing 2 is not particularly limited to that shown in the embodiment described above; for example, as shown in FIG. If it is formed into a trumpet shape, it is possible to improve the efficiency of introducing outside air to the vicinity of the power supply device. Further, the power supply device is not limited to that shown in this embodiment. For example, as shown in FIG. 50 and is attached to the embossed part 2 of the fuselage frame 1 through the power supply frame 50, in addition to providing ventilation holes 44 and 51 in the embossment 2 and the power supply frame 50 respectively, It is also necessary to open ventilation holes 52 at the site. This makes it possible to introduce outside air to the area around the power supply device.

[Effects of the Invention] As explained above, according to the power supply device mounting structure for a copying machine or the like according to the present invention, the convection of air from below to above is caused around the power supply device by utilizing the back side of the machine frame. Since this is forcibly generated, it is possible to reliably suppress the rise in air temperature around the power supply device without compromising handling safety, and as a result, heat resistance is not required as much as a power supply element. In addition to being able to use an inexpensive one, the 5A power supply unit itself can be protected from toner and dust floating within the aircraft frame. Furthermore, according to the present invention, it is possible to increase the surface rigidity of the area where the power supply device is installed without increasing the thickness of the fuselage frame.
The support strength of the power supply device can be improved while reducing the weight of the aircraft frame.

[Brief explanation of drawings]

FIG. 1 is a schematic perspective view showing an embodiment of a power supply device mounting structure for a copying machine or the like according to the present invention, and FIGS. 2 and 3 are front views and FIGS. 4 is a cross-sectional explanatory view showing a specific example of the installation of the power source VA position, FIG. 5 is a sectional view showing the installation state of the power supply device according to the embodiment, and FIG. FIG. 7 is a perspective view of a main part showing a modified example of the body frame, and an explanatory view showing a further example of the power supply device mounting structure for a biro machine or the like according to the present invention. [Explanation of symbols] (1) Airframe frame (2) Emboss (4) Air flow passage (10) Substrate (19) Power transistor (heating element) (20
)...Large capacity diode (heating element) (21)...
Three-terminal regulator (heating element) (30)...Radiation plate (34, 44, 51, 52)...Vent hole (ventilation path) (
50)...Power supply frame patent applicant Fuji Xerox Co., Ltd. Agent
Patent attorney Satoshi Nakamura (2 others) 1st cause P'spirit; I! u name 3 figure 34° trace 5 figure 4 figure 5

Claims (1)

[Claims] In a structure in which a power supply device is disposed on a body frame of a copying machine, etc., an emboss is formed on the body frame corresponding to the location where the power supply device is disposed to form an air flow passage in the lower part of the body frame. A power supply device mounting structure for a copying machine, etc., characterized in that a ventilation path is formed that communicates the air flow path with the vicinity of a heat generating part of the power supply device.