JPH02271099A - Electric fan - Google Patents

Abstract

PURPOSE:To reduce only the thickness of a blade without reduction of air quantity to decrease the thickness of a protective net by constructing a propeller fan by five blades, and forming the maximum size of the blade in front-rear direction less than 1.6 times the size of the blade boss. CONSTITUTION:The blade 4b of a fan 4 is constructed in such a way that the maximum thickness (b) of the blade is formed by 1.5 times in relation to the thickness (a) of a fitting part to a boss portion 4a and the fan is formed by five blades 4b. The area and the twist of the blade 4b are formed smaller in comparison with the conventional ones. Consequently, an air blasting quantity per one blade 4b is reduced, neverthless the number of the blade is increased to maintain the total air quantity. The size of the blade 4b in its front-rear direction can be reduced thereby and the thickness of a front protective net 5 and a rear protective net for covering the fan 4 can be reduced and, in addition, to the fact that a part of a motor 3 is covered by the boss portion 4a of the fan 4, the whole thickness can be reduced.

Description

[Detailed description of the invention] Industrial applications The present invention relates to an electric fan for home use.

BACKGROUND OF THE INVENTION In recent years, many electric fans used in homes have been designed with finer spacing between the core wires of the protective net to improve safety.

A conventional electric fan had a configuration as shown in FIG.

That is, a fan 102 with three to four blades is fixed to the rotating shaft of the motor 101, and a front protection net 103 and a rear protection net 104 are installed to cover the fan 102. Also, the front protection net 1o3. The rear protective net 104 has the core wires 103& arranged radially, and the interval between the core wires 103a is made small to ensure safety by preventing fingers from getting into the net.

Problems to be Solved by the Invention In such a conventional configuration, the blades 102a of the fan 102
Since the number of blades is 3 or 4, in order to obtain the desired air volume, it is necessary to greatly curve the blade 102a and increase the thickness of the blade 102a in the front and rear direction. 104 becomes large in the front-rear direction, and the thickness of the front and rear protective nets 103 and 104 becomes large.

In addition, the front and rear protective nets 103 and 104 have a structure in which the number of core wires 103a is increased and the gap between the core wires 103a is narrowed, and if used for a long period of time, dust will adhere and the wind speed will decrease. However, there was a problem in that the wind did not reach far away areas.

The present invention solves such conventional problems, and
It is an object of the present invention to provide a fan in which the longitudinal dimension of the rear protective net is shortened, that is, the thickness thereof is reduced, and the wind speed is less reduced even if some dust or the like adheres thereto.

Means for Solving the Problem In order to solve this problem, the present invention provides a six-blade propeller fan attached to the output shaft of a motor, and a front protective net and a rear protective net with narrow core wire spacing that cover this fan. , a base that supports the motor protruding from the rear protection net, and the blade has a configuration in which the maximum dimension of the blade in the longitudinal direction is 1.6 times or less the root dimension of the blade. It is something.

Substitute This configuration increases the number of blades compared to the conventional one, so even if the same air volume is produced, the amount of air blown per blade can be smaller, so the twist of the blade can be reduced and the area can be reduced.
The thickness of the expanded blade portion can be made smaller than the thickness of the root of the fan's blades, resulting in a thinner fan. In addition, by increasing the number of blades and reducing the twist, less wind escapes between the blades, allowing the wind to be continuously concentrated and sent forward.

EXAMPLE An example of the present invention will be described below with reference to FIGS. 1 and 2.

As shown in the figure, a fan 4 is fixed to the rotating shaft of the motor 3, and a front cover 1. The motor 3 covered by the rear jacket 2 is partially covered by the boss portion 4a of the fan 4. Also fan 4 f
The f14b is made up of five blades 4b that are attached to the boss portion 4a and have a maximum blade thickness b approximately 1.6 times larger than the thickness a of the portion.

This fan 4 has a front protection net 5 with a narrow interval between core wires 5a.
and is covered by a rear protection net 6.

The motor 3 has a rear part 3a of the motor 3 behind the rear protection net 6.
The base 7 supports the rear part 3a of the motor 3.

In the above configuration, the area of the blade 4b and the twist of the blade are smaller than before, so the amount of air blown per blade 4b is small, but because the number of blades is large, the total air volume is lower than before. They maintain almost the same value.

Therefore, since the longitudinal dimension (thickness) of g4b can be reduced, it is also possible to reduce the thickness of the front protection net 5 and the rear protection net 6 that cover the fan 4, and the motor 3
The motor 3 and the front are partly covered by the boss part 4a of the fan 4.

The overall thickness of the rear protection nets 5 and 6 can be reduced.

In addition, by making the blade 4b into a five-piece rod-like blade shape, compared to a conventional fan with three or four curved blades, it is possible to send air in a continuous and concentrated manner forward, making it possible to direct the wind. This makes it possible to send air to a longer distance, and the reduction in the blowing force against static pressure is reduced, and dust adheres to the front protection net 6 and the rear protection net 6, increasing air resistance. However, sudden decreases in air volume can be suppressed.

Effects of the Invention As is clear from the description of the above embodiments, the present invention has five fan blades, thereby reducing the thickness of the blades without reducing the conventional air volume. This makes it possible to realize an excellent electric fan in which the thickness of the protective net can be reduced, and even if air resistance increases due to dust adhering to the protective net, a significant decrease in air volume can be suppressed.

[Brief explanation of drawings]

Fig. 1 is a sectional view of essential parts of an electric fan according to an embodiment of the present invention;
This figure is a perspective view of the same, and FIG. 3 is a perspective view of a conventional electric fan. 3...Motor, 4...Fan, 4b.
...Wings, 5...Front protection net, 5t...
- Core wire, 6... Rear protection net, 7... Base. Name of agent: Patent attorney Shigetaka Awano and 1 other person
Figure 3-4-9 4--Fan Diagram 2

Claims (1)

[Claims] A five-blade propeller fan attached to the output shaft of a motor, a front protective net and a rear protective net with narrow core wire spacing that cover the fan, and a base that supports the motor and protrudes behind the protective net. An electric fan, wherein the blade has a maximum dimension in the longitudinal direction of 1.6 times or less of the root dimension of the blade.