JPH0412198A - Blower device - Google Patents

Abstract

PURPOSE:To blow a large air quantity with low noise in a small sized blower device used for a dryer and the like by providing a motor-driven mixed flow vane wheel in a nearly cylindrical blower duct, and forming the hub into specified truncated conical shape. CONSTITUTION:This blower device is provided with a mixed flow vane wheel 8 in a nearly cylindrical blower duct 1, a driving motor 3 positioned on the lower stream side of the wheel 8, and a heater 5 positioned on further lower stream side, the motor 3 is supported with stays 2 provided on the inside of the duct 1 on the center, and one end of the rotating shaft is directly connected to the mixed flow vane wheel 8. The vane wheel 8 is constituted so that a plurality of vanes are provided on the circumference of a hub of nearly truncated conical shape spreading on the lower stream side, diameter of the upper bottom 8b of the nearly truncated cone is smaller than diameter of the motor 3, and diameter of the lower bottom 8c is formed larger than diameter of the motor 3. Hereby, a blower device of small size, low noise, and a large air quantity is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a small-sized air blower equipped with a heater and used for drying a dryer or a toilet seat with a warm water bidet.

BACKGROUND OF THE INVENTION Conventionally, this type of blower device has used a small-sized white fan, a small fan, or a very old propeller fan. When a propeller fan is used, as shown in Fig. 2, a motor 3 is supported via a stay 2 in the center of the ventilation duct I, and a propeller fan 4 is directly connected to the upstream rotating shaft of the motor 3. .

Furthermore, a heater 5 is placed downstream of the motor 3.

In the above configuration, by rotating the propeller fan 4 with the motor 3, a flow shown by arrow a is generated.

The sucked room temperature air is heated as it passes through the heater 5 and is discharged as warm air.

In addition, when a sirocco fan is used, it becomes as shown in Fig. 3, and the mechanism of sucking room temperature air and discharging warm air through the heater 5 is the same, but the sirocco fan 6,
The arrangement of the motor 7 is quite different from that of the propeller fan 4, and the overall shape is also different.

Problems to be Solved by the Invention However, in the conventional air blowing devices as described above, neither the propeller fan nor the sirocco fan had sufficient performance. That is, a propeller fan is originally a low-pressure type blower, and the pressure is insufficient to blow air through a heater with a high pressure loss. In addition, the flow blown out from the Pro Hella fan hits the motor, which increases the turbulence of the flow, leading to a drop in efficiency. Therefore, high rotation speed was required, further increasing noise.

In addition, as shown in Figure 3, the size of a sirocco fan is considerably larger than that of a propeller fan, making it difficult to miniaturize and place inside equipment, and the manufacturing cost of the impeller and casing is high. Higher than propeller fan.

In this way, conventional blowers can achieve small size and low noise.
Another problem was that it was not possible to send enough warm air.

The present invention aims to solve such conventional problems and to provide a small-sized, low-noise, large-air blowing device using an axial flow type impeller.

Means for Solving the Problems In order to solve the above-mentioned problem R, the blower device of the present invention includes a mixed flow impeller, a drive motor located downstream of the mixed flow impeller, and a drive motor located further downstream of the mixed flow impeller in a substantially cylindrical blower duct. Equipped with a heater to
The motor is supported at the center of the air duct by a plurality of stays provided inside the air duct, and the mixed flow impeller is directly connected to one end of the rotating shaft, and the impeller is widened on the downstream side. It has a configuration in which a plurality of blades are provided around a substantially truncated conical hub, and the diameter of the upper base of the substantially truncated conical hub is set smaller than the diameter of the motor, and the diameter of the lower base is set smaller than the diameter of the motor. It has a large configuration.

Function The present invention employs a mixed flow impeller with excellent pressure characteristics due to the above-described configuration, so that it is less susceptible to the influence of pressure loss due to the heater on the downstream side. In addition, the diameter of the top bottom of the hub of the mixed flow impeller is small, which facilitates the inflow of suction flow, and the diameter of the bottom bottom is larger than the diameter of the motor located behind the hub. The flow of air blows smoothly without being disturbed by the motor, improving air blowing characteristics.

Example Embodiments of the present invention will be described below based on the accompanying drawings.

Note that parts that are the same as those in the conventional example are given the same numbers as in the first example, and explanations thereof will be omitted.

In FIG. 1, 8 is a mixed flow impeller, and the diameter of the upper base 8b of the hub 8a is smaller than the diameter of the motor 3, and the diameter of the lower base 8c is set larger than the diameter of the motor 3.

When blowing air by rotating the mixed flow impeller 8 with this configuration, since the diameter of the upper base 8b is small on the inlet side of the mixed flow impeller 8, the inflow area becomes large, which is advantageous for blowing a large amount of air. . Further, since the lower base 8c is larger than the upper base 8b on the blowing side, a higher discharge pressure than that of a propeller fan can be obtained due to the effect of centrifugal force.

Furthermore, since the diameter of the lower bottom 8c is larger than the diameter of the motor 3, the flow discharged from the mixed flow impeller 8 flows through the flow path sandwiched between the blower duct 1 and the motor 3 without colliding with the motor 3. Therefore, there is no pressure loss or efficiency drop due to turbulence.

In this way, by adopting an appropriate mixed flow impeller, it is possible to smoothly connect the suction flow to the discharge flow, suppress loss due to turbulence, and effectively utilize the boosting effect of centrifugal force to create a high-performance blower. I can do it.

Effects of the Invention As described above, according to the blower of the present invention, a mixed flow impeller is used instead of a propeller fan, the diameter of the upper base of the hub of the mixed flow impeller is made smaller than the diameter of the motor, and the diameter of the lower base of the hub of the mixed flow impeller is made smaller than the diameter of the motor. By making the diameter of the motor larger than the diameter of the motor, the following effects can be obtained.

(1) Since the diameter of the upper base is small, the inlet area surrounded by the air duct and hub is large, making it suitable for blowing large amounts of air.

(2) Since the diameter of the bottom is larger than the diameter of the motor, the discharge flow from the mixed flow impeller flows between the blower duct and the motor without hitting the motor, which reduces efficiency and increases pressure drop due to turbulence. (3) By using a mixed flow impeller, pressure increases due to the effect of centrifugal force, making it possible to provide sufficient ventilation even when a high-load heater is placed downstream.

As a result, it is possible to achieve the effect of realizing low noise while performing sufficient ventilation with a small blower.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a blower device in an embodiment of the present invention;
FIG. 2 is a cross-sectional view of a conventional blower using a propeller fan, and FIG. 3 is a cross-sectional view of this type of blower using a conventional sirocco fan. 1...Blower duct, 2...Stay, 3
...Motor, 5...Heater, 8...
...Mixed flow impeller, 8a...Hub, 8b...
...Top bottom, 8c...Bottom bottom. Name of agent: Patent attorney Shigetaka Awano and one other person.

Claims (1)

[Claims] A substantially cylindrical blower duct includes a mixed flow impeller, a driving motor located downstream of the mixed flow impeller, and a heater located further downstream. The mixed flow impeller is directly connected to one end of the rotating shaft, and the mixed flow impeller is provided with a plurality of blades around a substantially truncated conical hub whose downstream side is widened. . The air blowing device, wherein the diameter of the upper base of the substantially truncated conical hub is set smaller than the diameter of the motor, and the diameter of the lower base is set larger than the diameter of the motor.