JP5325030B2 - Fan motor mounting structure for electronic equipment - Google Patents

Description

  The present invention relates to a structure in which a cooling fan motor is attached to an electronic device, and relates to a technique for preventing destruction of an electronic circuit of the fan motor due to static electricity.

  In electronic devices such as hard disk recorders and DVD recorders, a fan motor is attached to forcibly air-cool the inside of the electronic device so that the temperature rise inside the housing is suppressed and the mounted electronic components operate normally. I have to. At that time, a fan cover is attached to the surface of the fan motor so that the user's hand does not touch the rotating impeller (blade). Even when the user carelessly touches the fan motor, the finger cover does not contact the fan motor by the fan cover, and safety is maintained. In general, a fan cover of a fan motor is made of an insulating material such as plastic for weight reduction and cost reduction. In order to reduce the size of the electronic device, the fan cover is disposed close to the fan motor.

  By the way, in an environment where the air is dry, static electricity tends to accumulate in the human body. When a charged user inadvertently touches the fan motor of an electronic device, the static electricity passes through the gap of the fan cover, which is an insulating material, from the fingertip, and is discharged to the electronic circuit portion of the fan motor, causing electrostatic damage to the fan motor. May end up.

  In order to prevent electrostatic breakdown of the fan motor due to such static electricity, the following countermeasures have been proposed. In the technique described in Patent Document 1, an aluminum layer is provided so as to cover electronic components arranged on the circuit board of the fan motor, and even if static electricity exists around the fan motor, the static electricity is blocked by the aluminum layer. Electronic components are not destroyed. In Patent Document 1, the aluminum layer is not connected to the ground. In the technique described in Patent Document 2, a cooling fan (fan motor) is fitted into a housing having a large number of ventilation holes to prevent leakage of electromagnetic waves from the fan mounting portion.

JP 2003-88046 A JP-A-8-264990

  The technique described in Patent Document 1 prevents destruction of electronic components by shielding static electricity with an aluminum layer. In this case, the aluminum layer is affixed to the base of the fan motor in the form of a nameplate seal sandwiched between both insulating layers, but the aluminum layer is not connected to ground. Therefore, as the amount of static electricity increases, the shielding effect is not sufficient, and the electronic component may be destroyed. In order to connect to the ground with the structure of Patent Document 1, the end of the aluminum layer must be extended and connected to the ground potential of the motor. As a result, the structure of the motor itself needs to be changed, and a general-purpose fan motor cannot be used as it is.

  In addition, since the technology described in Patent Document 2 is configured to cover the entire fan motor with a casing metal fitting, the metal material and processing cost of the metal fitting increase as compared with a plastic material and the like, and the air volume decreases to reduce the cooling performance. Will be reduced. In this case, if the vent hole is made larger, the air volume can be increased, but the shielding effect is lowered, and the fingertips can easily enter, which causes a safety problem.

  An object of the present invention is to provide a structure that prevents electrostatic destruction of an electronic circuit of a motor with a simple structure while using a general-purpose fan motor as it is in mounting a fan motor of an electronic device.

  The present invention is a fan motor mounting structure of an electronic device in which a fan motor for cooling and a fan cover made of an insulating material covering the fan motor are mounted on the electronic device, the fan motor having a rotor for rotating the impeller; A stator on which the coil is wound inside the rotor, and an electronic circuit that supplies electric power to the coil to drive the rotor to rotate, and the fan cover is configured to receive wind from the fan motor. When attaching the fan motor and the fan cover to the electronic device, having a slit to be passed, a conductive member that covers the region of the electronic circuit of the fan motor, and a ground connection terminal drawn from the conductive member The ground connection terminal is connected to the conductive casing of the electronic device.

  Here, the conductive member is a circular metal plate having a diameter substantially equal to the diameter of the rotor of the fan motor, and the ground connection terminal is integrally drawn from the metal plate.

  According to the present invention, a general-purpose fan motor can be attached to an electronic device, and electrostatic destruction of an electronic circuit of the motor can be prevented with a simple structure and a low-cost fan cover.

BRIEF DESCRIPTION OF THE DRAWINGS The whole block diagram which shows the 1st Example of the attachment structure of the fan motor of the electronic device which concerns on this invention. The block diagram which shows an example of the fan cover in a 1st Example. The longitudinal cross-sectional view which shows the attachment state of a fan motor and a fan cover. The figure which expanded the center part of sectional drawing of FIG. The block diagram which shows an example of the fan cover in a 2nd Example.

  Embodiments according to the present invention will be specifically described below with reference to the drawings.

  FIG. 1 is an overall configuration diagram showing a first embodiment of a fan motor mounting structure of an electronic apparatus according to the present invention. The electronic device 101 is an electronic device such as a hard disk recorder or a DVD recorder, and a fan motor 102 is incorporated in a casing (rear panel 105 in this case) to cool heat generated in the device. A general-purpose DC drive motor or the like is used as the fan motor 102. The surface of the fan motor 102 is covered with a fan cover 103, and is attached and fixed to a conductive casing of the device with screws 104. As will be described later, a conductive member for preventing static electricity is provided inside the fan cover 103 used here.

FIG. 2 is a configuration diagram illustrating an example of a fan cover in the first embodiment.
The fan cover 1 (103) is made of an inexpensive insulating material such as plastic, and is provided with tabs 3a and 3b for positioning on the housing (rear panel 105) of the electronic device 101 and screwed and fixed to the housing of the electronic device 101. Screw holes 4a, 4b, 4c and 4d, a slit 5 for passing cooling air generated by the fan motor 102, and a pressing portion 6 for ground connection. Further, a conductive member 2 for preventing static electricity was attached to the central portion inside the fan cover 1. Thereby, when static electricity enters from the outside of the fan cover 1, the conductive member 2 can be forcibly discharged to protect the electronic circuit of the fan motor 102.

  The conductive member 2 is formed by processing a metal plate such as stainless steel (thickness of about 0.1 to 0.2 mm) into a substantially circular shape, and the ground connection terminal 2a is integrally drawn out from a part thereof. The diameter D2 of the circular portion of the conductive member 2 is approximately equal to (or slightly larger than) the diameter D1 of the central portion (rotor 12 described later) of the fan motor 102. Thereby, the conductive member 2 covers the electronic circuit built in the central portion of the fan motor 102. Moreover, although the center part 2b of the electroconductive member 2 is cut out in the ring shape, since static electricity enters from the circumference | surroundings of a disc, there is no trouble in the antistatic effect.

  A retaining hole 2c provided in the conductive member 2 fixes the conductive member 2 to the fan cover 1 by fitting a minute protrusion 7 provided on the fan cover 1 side. When the fan cover 1 to which the conductive member 2 is attached is fixed to the electronic device 101, the pressing portion 6 of the fan cover 1 brings the ground connection terminal 2 a of the conductive member 2 into contact with the rear panel 105 of the electronic device 101. In this way, by conducting the conductive member 2 and the conductive casing of the electronic device 101, the electric charge accumulated in the conductive member 2 due to the discharge is released to the casing, and even if a large amount of static electricity enters, it is ensured. In addition, an antistatic effect can be obtained.

FIG. 3 is a vertical cross-sectional view showing a mounting state of the fan motor and the fan cover. The fan motor 10 (102) and the fan cover 1 (103) are attached to a rear panel 105 that is a casing of the electronic device.
The fan motor 10 (102) includes an impeller (blade) 11 that generates wind, a rotor 12 that is made of a magnet that rotates the impeller 11, and a shaft 13 that serves as a rotating shaft of the rotor 12. In addition, as a fixed portion, a casing 14 that supports the fan motor, a stator 15 surrounded by an insulating material around which a coil for powering the rotor 12 is wound, and the rotor 12 rotates by supplying electric power to the coil of the stator 15. And an electronic circuit 16 for driving. A gap 17 inevitably exists at the boundary between the rotor 12 and the stator 15.

  The fan cover 1 is composed of a slit 5 through which the air of the fan motor passes and a conductive member 2 attached to an inner central portion. The conductive member 2 is disposed so as to cover the area of the electronic circuit 16 built in the fan motor 10. Although not shown here, the ground connection terminal 2a of the conductive member 2 is connected to the rear panel 105 of the electronic device.

Next, a mechanism for preventing electrostatic breakdown of the fan motor by the fan cover of this embodiment will be described.
FIG. 4 is an enlarged view of the central portion of the cross-sectional view of FIG. In FIG. 4, the slits 5 of the fan cover 1 are provided in three circumferential rows, and are indicated by reference numerals 5a, 5b, and 5c from the inside. Static electricity passes from the outside of the fan cover 1 through the slits 5a, 5b, 5c and enters the fan motor to be discharged.

  First, the discharge path in the case of a conventional structure in which the conductive member 2 is not attached to the fan cover 1 will be described. The route in this case is indicated by a broken line arrow 20. For example, if static electricity enters from the slit 5a, the nearest fan cover 1 is an insulating material and therefore does not discharge directly to the fan cover. Next, the part existing near the slit 5a is the casing 14, but since this is also an insulating material, it is not directly discharged. Next, a gap 17 formed between the rotor 12 and the stator 15 exists. The electronic circuit 16 is exposed with respect to the gap 17, and the electric circuit 16 is discharged through the gap 17. The same applies to the case where the entrance of static electricity is the slit 5b or the slit 5c, and only the distance to the center of the fan motor changes, and the electronic circuit 16 of the fan motor is discharged. This discharge destroys the electronic circuit 16, and the fan motor does not operate.

  Next, the discharge path in the case of the present embodiment in which the conductive member 2 is attached to the fan cover 1 will be described. The path in this case is indicated by a solid arrow 21. When static electricity enters from the slit 5a, it is discharged to the nearest conductive member 2 and is not discharged to the electronic circuit 16 in the motor. The same applies to the case where the entrance position of static electricity is the slit 5b or the slit 5c, and the conductive member 2 is discharged. The discharge destination at this time is determined by the distance relationship between the conductive member 2 and the electronic circuit 16 as viewed from the entrance position of static electricity, but the discharge destination of the electronic circuit 16 is actually a metal portion (for example, a pin) on the substrate. From the distance to the conductive member 2. Moreover, since the electric charge discharged to the conductive member 2 flows into the housing via the ground connection terminal 2a, it is possible to reliably prevent static electricity from being discharged to the fan motor. The above is the mechanism for preventing electrostatic breakdown of the fan motor in this embodiment.

  As described above, in this embodiment, the static electricity that has entered the fan cover is discharged to the conductive member attached to the central portion of the fan cover and then flows to the rear panel of the electronic device. Destruction can be reliably prevented. As a result, it is possible to prevent an abnormal temperature rise inside the electronic device due to destruction of the fan motor, which contributes to improving the reliability of the electronic device. In the case of the present embodiment, since a general-purpose fan motor can be used as it is, it is highly practical.

  In addition, the following form is also possible as a modification of the present embodiment. The ground connection terminal 2a of the conductive member 2 is configured to contact the housing of the electronic device. However, if the ground connection terminal 2a can be discharged from the ground connection terminal 2a to the housing of the electronic device when receiving static electricity, A structure arranged close to each other without contact may be used. Further, although the conductive member 2 is attached to the central portion inside the fan cover 1, the conductive member 2 may be attached to the central portion outside the fan cover 1.

  Next, a second embodiment of the fan motor mounting structure of the electronic apparatus according to the present invention will be described. The overall configuration diagram of the electronic device is the same as that of the first embodiment (FIG. 1), and a description thereof will be omitted.

FIG. 5 is a configuration diagram showing an example of a fan cover in the second embodiment.
The fan cover 1 ′ is made of an insulating material such as plastic, and, like the first embodiment (FIG. 2), the claws 3 a and 3 b for positioning on the housing of the electronic device 101 and the screws on the housing of the electronic device 101. It has screw holes 4a, 4b, 4c, 4d for fixing and a slit 5 for passing cooling air generated by the fan motor 102. A conductive member 2 ′ was attached. In this embodiment, the ground connection pressing portion 6 in FIG. 2 is not required.

  The conductive member 2 ′ is obtained by forming a metal plate such as stainless steel into a substantially circular shape, and the shape of the circular portion is the same as in FIG. 2. In this embodiment, the ground connection terminal 2d is integrally drawn out from a part of the conductive member 2 '. And the hole provided in this earth connection terminal 2d is made to correspond with the position of one (for example, 4d) of the screw hole of fan cover 1 '. When the conductive member 2 ′ is fixed to the fan cover 1 ′ and the fan cover 1 ′ to which the conductive member 2 ′ is attached is screwed and fixed to the electronic device 101, the conductive member 2 ′ and the electronic device are fixed by the screw 104. The housing 101 is made conductive.

  According to the present embodiment, the static electricity that has entered through the slit 5 of the fan cover 1 ′ is discharged to the conductive member 2 ′, and the electric charge accumulated in the conductive member 2 ′ by the discharge passes through the ground connection terminal 2d. To escape to the housing. Thereby, it is possible to prevent static electricity from being discharged to the electronic circuit of the fan motor and to prevent the fan motor from being destroyed.

  In the case of the present embodiment, the screw holes 4a to 4d of the fan cover 1 'are used for ground connection, and therefore the pressing portion 6 as shown in FIG. 2 is not required for the fan cover 1'. Therefore, a general-purpose fan cover can be used and is more practical. Further, since the ground connection terminal 2d of the conductive member 2 'can be formed on substantially the same surface, the bending process is unnecessary and the process is easy.

  In addition, the following form is also possible as a modification of the present embodiment. The ground connection terminal 2d of the conductive member 2 'is structured to be electrically connected to the housing of the electronic device via a screw. However, when receiving static electricity, the ground connection terminal 2d is connected to the screw (or the housing of the electronic device). As long as the distance can be discharged, the structure may be arranged in close proximity without contacting the screw. In addition, the conductive member 2 ′ is attached to the central portion inside the fan cover 1 ′, but may be attached to the central portion outside the fan cover 1 ′.

1, 1 ', 103 ... Fan cover,
2, 2 '... conductive member,
2a, 2d ... ground connection terminals,
3a, 3b ... nail,
4a, 4b, 4c, 4d ... screw holes,
5, 5a, 5b, 5c ... slits,
6 ... holding part,
7 ... protrusions,
10, 102 ... Fan motor,
11 ... impeller,
12 ... Rotor,
13 ... shaft,
14 ... casing,
15 ... Stator,
16 ... electronic circuit,
17 ... Gap,
20, 21 ... discharge path,
101 ... electronic equipment,
104 ... Screw,
105: Rear panel.

Claims (5)

A fan motor mounting structure for an electronic device in which a cooling fan motor and a fan cover made of an insulating material covering the fan motor are mounted on the electronic device,
The fan motor is
A rotor that rotates the impeller,
A stator on the inside of the rotor and having a coil wound thereon;
An electronic circuit that supplies electric power to the coil to rotate the rotor;
The fan cover is
A slit for passing the wind from the fan motor;
A conductive member covering a region of the electronic circuit of the fan motor;
Having a ground connection terminal drawn from the conductive member;
The conductive member is provided with a stop hole, and by fitting a protrusion provided on the fan cover side into the stop hole, the conductive member is fixed close to the slit, and
When mounting the fan motor and the fan cover to the electronic device, the ground connection terminal is connected to a conductive casing of the electronic device. It is the fan motor attachment structure of the electronic device of Claim 1, Comprising:
The conductive member is a circular metal plate substantially equal to the diameter of the rotor of the fan motor,
A fan motor mounting structure for an electronic device, wherein the ground connection terminal is formed by being integrally drawn from the metal plate. A fan motor mounting structure for an electronic device according to claim 1 or 2,
A structure for mounting a fan motor of an electronic device, wherein the ground connection terminal is brought into contact with a conductive casing of the electronic device by a pressing portion provided on the fan cover. A fan motor mounting structure for an electronic device according to claim 1 or 2,
A fan motor mounting structure for an electronic device, wherein the ground connection terminal is electrically connected to a conductive casing of the electronic device by being screwed by a screw hole provided in the fan cover. A fan motor mounting structure for an electronic device in which a cooling fan motor and a fan cover made of an insulating material covering the fan motor are mounted on the electronic device,
The fan motor is
A rotor that rotates the impeller,
A stator on the inside of the rotor and having a coil wound thereon;
An electronic circuit that supplies electric power to the coil to rotate the rotor;
The fan cover is
A slit for passing the wind from the fan motor;
A conductive member covering a region of the electronic circuit of the fan motor;
Having a ground connection terminal drawn from the conductive member;
The conductive member is provided with a stop hole, and by fitting a protrusion provided on the fan cover side into the stop hole, the conductive member is fixed close to the slit, and
When mounting the fan motor and the fan cover to the electronic device, the ground connection terminal is disposed close to a distance that can be discharged to the conductive casing of the electronic device. .

Images