JP2005120991A - Box-shaped fan for freezing and refrigerating showcase - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a box-shaped fan for a freezing and refrigerating showcase, preventing the generation of unusual sounds due to frost formation and the rotation stop of blades even when using the small size box-shaped fan. <P>SOLUTION: The box-shaped fan 5 is used for supplying cold air to be circulated in a display chamber 1 of the freezing and refrigerating showcase. The box-shaped fan 5 comprises a mounting frame 12 having a vent aperture 11 and a motor 14 having three integrated blades 13. The mounting frame 12 includes an outer periphery frame member 15, a boss member 16 for supporting and fixing the motor 14 onto the center of the vent aperture 11, and four stay members 17 for connecting the outer periphery frame member 15 to the boss member 16. The mounting frame 12 and the blades 13 are formed of glass fiber containing synthetic resin, respectively. Coatings of high water repellent paint are formed on the outer surfaces of the outer periphery frame member 15, the stay members 17 and the blades 13. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a box type fan for a refrigerated showcase for circulating and supplying cold air to a display room of the refrigerated showcase.

  Patent Documents 1 and 2 disclose a fan for a refrigerated refrigeration showcase that circulates and supplies cold air cooled by a heat exchanger into a display room to cool products in the display room. In the blower fans disclosed in Patent Documents 1 and 2, water repellency plating is applied to the surfaces of the blades or a water-repellent paint is applied to reduce frost formation on the blades.

JP-A-11-212327 (paragraph number 0013, FIG. 1-3) JP-A-11-281232 (paragraph number 0020, FIG. 1)

  In this type of blower fan, a small box-type fan is used in view of ease of mounting work and production cost. As shown in FIGS. 1 and 2, the box-type fan includes a mounting frame 12 having a vent hole 11 and a motor 14 having blades 13. The mounting frame 12 includes an outer peripheral frame member 15 and a vent hole 11. Includes a boss member 16 that supports and fixes the motor 14, and a stay member 17 that connects the outer peripheral frame member 15 and the boss member 16.

  The present inventor examined a small box-type fan attached to a freezer / refrigerated showcase, and because the blade 13 is close to the inner wall surface and the stay member 17 facing the ventilation opening 11 of the mounting frame 12, how much the blade It was found that even if frost formation on 13 was prevented, the blade 13 contacted the frost adhering to the mounting frame 12 and the stay 17.

  In this case, abnormal sounds are generated due to the contact, and the rotation of the blades 13 is stopped. In particular, if the mounting frame 12, the stay member 17 and the blades 13 are made of metal, it is easy to be cooled and the amount of frost formation is increased, and the occurrence of the abnormal noise is further easily caused.

  Accordingly, an object of the present invention is to prevent generation of abnormal noise due to frost formation, blade rotation stoppage, and the like even when a small box-type fan is used.

  As shown in FIG. 3, the present invention is directed to a box type fan that circulates and supplies cold air to the display room 1 of the refrigerated display case. As shown in FIGS. 1 and 2, the box-type fan 5 includes a mounting frame 12 having a ventilation port 11 and a motor 14 in which blades 13 are integrated. The mounting frame 12 includes an outer peripheral frame member 15, a ventilation port. 11 includes a boss member 16 that supports and fixes the motor 14 and a stay member 17 that connects the outer peripheral frame member 15 and the boss member 16, and the mounting frame 12 and the blade 13 are made of synthetic resin material containing glass fiber. Each of them is molded, and a coating film made of a highly water-repellent paint is formed on at least the inner wall surface of the outer peripheral frame member 15 facing the ventilation hole 11, the stay member 17, and the outer surfaces of the blades 13. It is characterized by.

  As the highly water-repellent coating material, a coating material having a static contact angle T between 150 ° and 180 ° between the coating film 21 and the water droplet 22 shown in FIG. 4 can be used.

  According to the present invention, since the highly water-repellent coating film is formed not only on the blade 13 but also on the inner wall surface facing the ventilation port 11 of the mounting frame 12 and the outer surface of the stay member 17, the blade 13 and the ventilation port 11. As a result, frost formation between the inner wall surface facing to the stay member 17 and the stay member 17 is reduced, and generation of abnormal noise due to frost formation and rotation stoppage of the blades 13 can be reliably prevented.

  And since the attachment frame 12 and the blade | wing 13 are formed with the synthetic resin material containing glass fiber, the same intensity | strength as the case where it forms with a metal is obtained, and it becomes difficult to cool and can reduce frost formation more reliably.

  FIG. 3 shows a vertical freezing and refrigeration showcase to which the present invention is applied. The case main body includes a display chamber 1 having an open front surface and a circulation path 2 for circulating cold air. In the display room 1, display shelves 3 for product display of upper and lower multi-stages are arranged. The circulation path 2 is provided between the peripheral wall of the display chamber 1 and the heat insulating outer wall 4 of the case body. A box type fan 5 and a heat exchanger 6 are arranged on the upstream side in the circulation path 2.

  The cold air cooled by the heat exchanger 6 is blown out from the cold air outlet 7 into the display chamber 1 through the circulation path 2 by the ventilation of the box-type fan 5, and then sucked into the circulation path 2 from the cold air inlet 8. And circulate to the heat exchanger 6. Thereby, cold air is circulated and supplied to the display chamber 1.

  As shown in FIGS. 1 and 2, the box-type fan 5 is a small axial fan, and a motor 14 in which a thin rectangular mounting frame 12 having a vent hole 11 and three blades 13 are integrated. Including. The mounting frame 12 includes an outer peripheral frame member 15, a boss member 16 that supports and fixes the motor 14 at the center of the vent hole 11, and four stay members 17 that connect the outer peripheral frame member 15 and the boss member 16. .

  The ventilation port 11 of the attachment frame 12 is formed in a tapered shape on the upstream side in the blowing direction. The outer peripheral frame member 15, the boss member 16, and the stay member 17 are integrally formed.

  The fan boss 18 formed integrally with the blade 13 also serves as a case on the rotor side of the motor 14. Each stay member 17 faces the ventilation opening 11 of the mounting frame 12 in a state where the stay member 17 is inclined obliquely with respect to the rotation direction K of the blade 13. The boss member 16 supports the stator side of the motor 14. The rotor of the motor 14 includes a permanent magnet, and the stator of the motor 14 includes an electromagnetic coil.

  The boss member 16 protrudes from the mounting frame 12 to the downstream side in the blowing direction H, and the tip side of each blade 13 protrudes from the mounting frame 12 to the upstream side in the blowing direction H. A lead wire 19 for wiring to the motor 14 is fixed to one stay member 17. The motor 14 is driven by DC12V.

  The mounting frame 12 and the blade 13 including the fan boss 18 are each a synthetic resin made of a composite resin of black polybutylene terephthalate (PBT) resin containing glass fiber for reinforcement and acrylonitrile butadiene styrene (ABS) resin. It is formed of a material, and a coating film made of a highly water-repellent paint is formed on the surface.

  The highly water-repellent paint is mainly composed of fluororesin powder and fluorine-based varnish. As shown in FIG. 4, a paint having a static contact angle T between the coating film 21 and the water droplet 22 of 150 ° or more is used. Yes. “HIREC450” manufactured by NTT Advanced Technology Co., Ltd. was used as the highly water-repellent paint.

  The box-type fan 5 is assembled after spraying a highly water-repellent paint on the outer surfaces of the mounting frame 12 and the blades 13 including the fan bosses 18 and then mounted (the state shown in FIG. 3).

  The cool air easily contains moisture because it contacts the outside air in the display chamber 1, and this moisture causes condensation on the outer surfaces of the mounting frame 12 and the blades 13. The water droplets 22 generated by this condensation are almost spherical due to the highly water-repellent coating film 21 (see FIG. 4), and roll on the highly water-repellent coating film 21 and fall off the box-type fan 5. This prevents the water droplets 22 from remaining on the outer surfaces of the mounting frame 12 and the blades 13 and freezing.

  Since the water droplet 22 is more likely to roll as the stationary contact angle T approaches 180 ° and approaches the sphere, as a highly water-repellent coating, the stationary contact angle T between the coating film 21 and the water droplet 22 is 150 ° to 180 °. Is selected.

  Condensation is likely to occur on the inner wall surface of the vent hole 11 of the mounting frame 12 and the leading edge in the rotational direction of each stay member 17 and each blade 13. The outer surface of the inner wall surface, each stay member 17 and each blade 13 may be painted, and it is not necessary to apply the entire box type fan 5. Alternatively, after assembling the box-type fan 5, a highly water-repellent paint may be sprayed onto the box-type fan 5.

  The refrigerator-freezer showcase may be provided with a plurality of box-type fans 5 as necessary. The refrigerated showcase may be either refrigerated or frozen only, or may be a flat open showcase.

Rear view of box type fan Step view of box-type fan Sectional drawing which shows the structure of a freezer / refrigerator showcase Diagram explaining the static contact angle between the coating film and water droplets

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Display chamber 2 Circulation path 5 Box type fan 11 Ventilation hole 12 Mounting frame 13 Blade 14 Motor 15 Outer frame part 16 Boss member 17 Stay member 21 Coating film 22 Water drop T Still contact angle

Claims (2)

A box-type fan for circulating and supplying cold air to the display room 1 of the refrigerated display case,
Including a mounting frame 12 having a ventilation opening 11 and a motor 14 in which a blade 13 is integrated;
The mounting frame 12 includes an outer peripheral frame member 15, a boss member 16 that supports and fixes the motor 14 at the center of the vent hole 11, and a stay member 17 that connects the outer peripheral frame member 15 and the boss member 16.
The mounting frame 12 and the blade 13 are each formed of a synthetic resin material containing glass fiber,
A freezing and refrigeration characterized in that a coating film made of a highly water-repellent paint is formed on at least the inner wall surface of the outer peripheral frame member 15 facing the vent hole 11, the stay member 17, and the outer surfaces of the blades 13. Showcase box-type fan.   The box-type fan for a refrigerator-freezer showcase according to claim 1, wherein a paint having a static contact angle T between 150 ° and 180 ° between the coating film 21 and the water droplets 22 is used as the highly water-repellent paint.

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