JPH05133391A - Electric blower - Google Patents

Abstract

PURPOSE:To get an electric blower high in air blow efficiency by suppressing the occurrence of the circulation air current which passes and flows through the space between an impeller and a casing. CONSTITUTION:This blower is equipped with a motor 11 and a casing 9, which is attached to the motor frame 12 and includes an impeller 14 and an air guide 13. This impeller 14 has a front shroud 15, a rear shroud 16, and a brake 17, and the suction part of the casing 9 is positioned in the suction port 14a of this impeller 14. And, a ring-shaped seal member 18 is attached, in the vicinity to the inside of the suction port 10 of the casing 9, to the suction port 14a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric blower used in a vacuum cleaner.

[0002]

2. Description of the Related Art In recent years, vacuum cleaners are characterized by enhanced suction power and reduced operating noise.
The electric blowers used are also producing many new technologies related to efficiency and noise.

A conventional electric blower will be described below. In FIG. 5, reference numeral 1 denotes a casing, and the impeller 2
-Has an air guide 3. Reference numeral 4 denotes a motor, which is directly connected to the impeller 2. Again impeller 2
Front shroud 5, blade 6, rear shroud 7
It consists of and. Reference numeral 8 denotes an airflow suction portion provided in the casing 1.

The operation of the electric blower configured as described above will be described below. The motor 4 rotates the impeller 2 at high speed to obtain the required air volume. At this time, the airflow flows from the suction portion 8, passes through the air guide 3 from the inside of the impeller 2, passes through the inside of the motor 4, and flows out to the outside. In this process, the dynamic pressure of the air flow discharged from the impeller 2 is converted into static pressure. In this way, the required vacuum pressure is obtained.

[0005]

However, the above-mentioned conventional structure has the following problems. The radial gap between the casing 1 and the suction portion 8 of the impeller 2 has a shape as shown in FIG. Since the front shroud 5 constituting the impeller 2 is made of a plate-shaped metal having a curved surface, the upstream dimension A becomes smaller than the downstream dimension B with respect to the suction portion 8 of the casing 1 at the suction port end portion of the front shroud 5. It is bigger than that. In other words, it has a "wedge-shaped guide passage shape". Therefore, a part of the air flow that should flow from the suction portion 8 and flow into the air guide 3 flows backward from the discharge port of the impeller 5 and passes through the clearance existing between the casing 1 and the front shroud 5 of the impeller 2. As a result, the circulation flow again flows into the impeller 2 from the "wedge-shaped guide passage shape". This is one of the major factors that lower the ventilation efficiency as a whole.

The present invention solves the above-mentioned conventional problems, and a first object of the present invention is to obtain an electric blower which eliminates the circulating flow by a simple means and has a high blowing efficiency. A second object is to obtain an electric blower that surely eliminates the circulating flow and further improves the blowing efficiency.

[0007]

[Means for Solving the Problems] A first means of the present invention for achieving the above-mentioned first object comprises a motor and a casing attached to a motor frame of the motor and containing an impeller and an air guide. The impeller has a front shroud and a rear shroud blade, the suction part of the casing is located at the suction port of the impeller, and the suction port is located close to the inside of the suction part of the casing. The electric blower is provided with a ring-shaped seal member.

A second means of the present invention for achieving the second object is, in addition to the constitution of the first means of the present invention,
Second having blade action on the casing side of the front shroud
The electric blower is equipped with the seal member.

[0009]

According to the first means of the present invention, the suction portion of the casing is located at the suction port of the impeller, and the ring-shaped sealing member is provided at the suction port so as to be close to the inside of the suction portion of the casing. Because I installed it,
The action of the seal member suppresses the flow into the gap between the casing and the front shroud. Therefore, the circulation flow itself is less likely to occur, and the overall blowing efficiency is increased.

Further, according to the second means of the present invention, since the second seal member having a blade action is attached to the casing side of the front shroud, the air flow generated from the second seal member by the rotation of the impeller circulates. It acts to push back the air flow. Therefore, the blowing efficiency is further increased.

[0011]

【Example】

(Embodiment 1) An embodiment of the first means of the present invention will be described below with reference to FIGS. 9 is a casing,
It includes an impeller 14 and an air guide 13, and has a suction portion 10 in the center. The side of the casing 9 opposite to the suction portion 10 is attached to the outer peripheral portion of the air guide 13 which also serves as the motor frame 12 of the motor 11 so as to prevent air leakage. 14 is a centrifugal impeller, which is composed of a front shroud 15, a rear shroud 16 and a plurality of blades 17 made of a metal plate,
They are crimped together to form an integrated structure. The suction portion 10 of the casing 9 is located at the suction opening 14a of the impeller 14, and the suction portion 1 of the casing 9 is provided at the front shroud 15 of the suction opening 14a.
A ring-shaped seal member 18 made of rubber, felt, or the like is attached so as to be close to the inside of 0. In this seal member 18, the inner diameter D of the end surface on the suction portion 10 side is smaller than the inner diameter C on the rear shroud 16 side. That is, the upper side of the seal member 18 is close to the suction portion 10. 19 is a clearance between the front shroud 15 and the casing 9.

The operation of this embodiment will be described below. When the impeller 14 rotates at high speed by the motor 11, air is sucked from the suction portion 10 of the casing 9.
As this air passes through the impeller 14,
It is given static pressure and dynamic pressure, which is the wind speed. In this way, the air that has passed through the impeller 14 flows into the air guide 13. However, since the pressure of the air discharged from the impeller 14 is lower on the suction portion 10 side, a circulating air flow that flows to the suction portion 10 side through the clearance 19 is about to be generated. However, in this embodiment, the seal member 18 attached to the front shroud 15 is present near the suction portion 10. This seal member 18
Has a shape that closes the inside of the suction portion 10 and shuts off the flow, and acts to suppress the circulating air flow.
For this reason, the resistance is increased here, and therefore the circulating air flow itself is difficult to generate. As described above, according to the present embodiment, the generation of the circulating air flow can be suppressed, so that the electric blower can have a high blowing efficiency.

(Embodiment 2) Next, an embodiment of the second means of the present invention will be described with reference to FIGS. Example 1
The same parts as those in FIG. In this embodiment, a seal member 20 similar to the seal member 18 of the first embodiment is provided, and a second seal member 21 having a blade action is attached to the front shroud 15 on the casing 9 side integrally with the seal member 20. It is a thing. The second seal member 21 does not necessarily have to be integrated with the seal member 20, and a plurality of second seal members 21 are formed.

The operation of this embodiment will be described below. Similar to the first embodiment, when the impeller 14 rotates at high speed, a circulating air flow is about to be generated. In this embodiment, the second seal member 21 has a blade action. That is, impeller 1
Simultaneously with the rotation of 4, the second seal member 21 also rotates, and a circumferentially rotating air flow is generated in this portion. Therefore,
The circulation flow that has passed through the clearance 19 is pushed back by the air flow. In other words, this embodiment uses the seal member 20.
In addition to the resistance of the flow between the impeller 14 and the casing 9 due to the above, the action of the second seal member 21 is added, so that an electric blower having a higher blowing efficiency can be obtained.

[0015]

As described above, according to the first means of the present invention, the suction part of the casing is located at the suction port of the impeller, and the suction port is close to the inside of the suction part of the casing. Since the ring-shaped seal member is attached in this manner, the action of the seal member suppresses the flow into the gap between the casing and the front shroud. Therefore, it is possible to obtain an electric blower with high ventilation efficiency by eliminating the circulation flow by a simple means.

Further, according to the second means of the present invention, since the second seal member having a blade action is attached to the casing side of the front shroud, the air flow generated from the second seal member by the rotation of the impeller circulates. It acts to push back the air flow. Therefore, the effect of the first means can be obtained, the circulating flow can be surely eliminated, and the blowing efficiency can be further enhanced.

[Brief description of drawings]

FIG. 1 is a partial sectional view of an electric blower according to an embodiment of the first means of the present invention.

FIG. 2 is a cross-sectional view of main parts of the electric blower.

FIG. 3 is a partial sectional view of an electric blower according to an embodiment of the second means of the present invention.

FIG. 4 is a cross-sectional view of the main parts of the electric blower.

FIG. 5 is a partial sectional view of a conventional electric blower.

FIG. 6 is a sectional view of a main part of the electric blower.

[Explanation of symbols]

 9 Casing 10 Suction Part 11 Motor 14 Impeller 14a Suction Port 15 Front Shroud 16 Rear Shroud 17 Blade 18 Sealing Member 18a Second Sealing Member

Claims (2)

[Claims] 1. A motor, and a casing attached to a motor frame of the motor and containing an impeller and an air guide. The impeller has a front shroud and a rear shroud blade, and a suction port of the impeller includes: An electric blower in which a suction portion of the casing is positioned and a ring-shaped seal member is attached to the suction port in the vicinity of the inside of the suction portion of the casing. 2. The electric blower according to claim 1, wherein a second seal member having a blade action is attached to the casing side of the front shroud.