Handheld blower

Patent metadata

Field	Value
Publication number	US-10264739-B2
Application number	US-201816035003-A
Country	US
Kind code	B2
Filing date	Jul 13, 2018
Priority date	Feb 20, 2013
Publication date	Apr 23, 2019
Grant date	Apr 23, 2019

Abstract

A handheld blower includes a housing having an air inlet and a duct assembly mounted in front of the air inlet, the duct assembly including a duct connected with the housing, a motor and a fan mounted in the duct, a battery, and a blowpipe connected to the housing by the duct assembly, the blowpipe defining a central axis in the length direction, and a handle arranged above the housing and the battery. The handle includes a gripping portion arranged on opposite sides of a plane in which the gravity center of the blower is located, and the plane is parallel to a central axis of the blowpipe and substantially perpendicular to a working ground. The gravity center of the handheld blower is adjacent to the gripping portion which enhances the handling comfort and reduces operator fatigue during long times of operation.

First claim

What is claimed is:

1. A handheld blower, comprising:
a fan for generating an air flow;
a motor for driving the fan to rotate about a central axis;
an air duct assembly comprising an air duct extending along the central axis, the air duct assembly having an inlet end and an outlet end respectively located at opposite ends of the air duct assembly;
a supporting ring arranged in the duct, the supporting ring including an accommodating portion in front of the hub of the fan and configured for accommodating the motor;
a battery coupling portion located at a distance from the inlet end of the air duct assembly and configured for coupling a battery pack thereto; and
a connecting portion configured to extend between the battery coupling portion and the inlet end of the air duct assembly, the connecting portion including at least one side opened region at a left or right side of the connecting portion so as to let an outer air flow to be induced from the at least one opened region into the inlet end of the air duct assembly and further to the outlet end of the air duct assembly by the fan.

2. The handheld blower according to claim 1 , wherein the motor is a brushless DC motor having a diameter less than or equal to 35 mm, and a ratio of the airflow rate of the handheld blower to a diameter of the brushless DC motor is larger than 12 cfm/mm.

3. The handheld blower according to claim 1 , wherein along a direction of a central axis of the blowpipe, an area of a flow cross-section of an air passage at a rear end of the fan adjacent to an air inlet is greater than that of the flow cross-section at an air outlet of the air duct assembly, and a flow-through area is formed between an inner wall of the housing and a hub of the fan, and wherein a ratio between an area of a flowing cross-section of the air outlet of the air duct assembly and an area of the flow cross-section of the flow-through area at the position of the fan is greater than or equal to 0.8.

4. The handheld blower according to claim 1 , further comprising a handle arranged above the connecting portion and the battery coupling portion, the handle comprises a gripping portion, arranged on opposite sides of a plane in which a gravity center of the whole blower is located, and the plane is parallel to a central axis defined by the air duct assembly and substantially perpendicular to a working ground.

5. The handheld blower according to claim 4 , wherein the housing has an accommodating chamber and a bending portion for turning the airflow, and the handle is arranged on a bending portion of the housing.

6. The handheld blower according to claim 1 , wherein the operational airflow of the handheld blower has an airflow rate in the range from 430 cfm to 700 cfm and a working time longer than 5 min.

7. The handheld blower according to claims 1 , wherein the ratio of the operational airflow rate to the power to the motor is larger than or equal to 0.7 cfm/w when the handheld blower is operated at a maximum operational airflow rate.

8. The handheld blower according to claims 1 , wherein the battery has a capacity larger than 170 wh.

9. A blower, comprising:
a fan for generating an air flow;
a motor for driving the fan to rotate about a central axis;
an air duct assembly comprising an air duct extending along the central axis, the air duct assembly having an inlet end and an outlet end respectively located at opposite ends of the air duct assembly;
a battery coupling portion located at a distance from the inlet end of the air duct assembly and configured for coupling a battery pack capable of supplying power to the motor;
a connecting portion configured to extend between the coupling portion and the inlet end of the air duct assembly; and

a gripping portion for a user to grip,
wherein the fan is received in the air duct, the inlet end of the air duct assembly is located between the outlet end and the coupling portion, the gripping portion defining a vertical plane configured to pass through the central axis and an air duct assembly defining a horizontal plane passing through the central axis, the connecting portion comprising a circumferential surface including one or more air intake sections located at one of four regions divided by the vertical plane of the gripping portion and the horizontal plane of the air duct assembly so as to let an outer air flow to be induced from the air intake sections into the inlet end of the air duct assembly and further to the outlet end of the air duct assembly by the fan.

10. The handheld blower according to claim 9 , wherein the motor is a brushless DC motor having a diameter less than or equal to 35 mm, and a ratio of the airflow rate of the handheld blower to a diameter of the brushless DC motor is larger than 12 cfm/mm.

11. The handheld blower according to claim 9 , wherein along a direction of a central axis of the blowpipe, an area of a flow cross-section of an air passage at a rear end of the fan adjacent to an air inlet is greater than that of the flow cross-section at an air outlet of the air duct assembly, and a flow-through area is formed between an inner wall of the housing and a hub of the fan, and wherein a ratio between an area of a flowing cross-section of the air outlet of the air duct assembly and an area of the flow cross-section of the flow-through area at the position of the fan is greater than or equal to 0.8.

12. The handheld blower according to claim 9 , further comprising a handle arranged above the housing and the battery coupling portion, the handle comprises a gripping portion, arranged on opposite sides of a plane in which a gravity center of the whole blower is located, and the plane is parallel to a central axis defined by the air duct assembly and substantially perpendicular to a working ground.

13. The handheld blower according to claim 12 , wherein the housing has an accommodating chamber and a bending portion for turning the airflow, and the handle is arranged on a bending portion of the housing.

14. The handheld blower according to claims 9 , wherein the ratio of the operational airflow rate to the power to the motor is larger than or equal to 0.7 cfm/w when the handheld blower is operated at a maximum operational airflow rate.

15. The handheld blower according to claims 9 , wherein the battery has a capacity larger than 170 wh.

16. A handheld blower, comprising:
a fan for generating an air flow;
a motor for driving the fan to rotate about a central axis;
an air duct assembly comprising an air duct extending along the central axis, the air duct assembly having an inlet end and an outlet end respectively located at opposite ends of the air duct assembly;
a battery coupling portion located at a distance from the end inlet of the air duct assembly and configured for coupling the battery pack thereto; and
a connecting portion configured to extend between the battery coupling portion and the inlet end of the air duct assembly, the connecting portion configured to be at least partly opened around a radial direction of the central axis of the motor so as to let an outer air flow to be induced from the connecting portion into the inlet end of the air duct assembly and further to the outlet end of the air duct assembly by the fan.

17. The handheld blower according to claim 16 , wherein the motor is a brushless DC motor having a diameter less than or equal to 35 mm, and a ratio of the airflow rate of the handheld blower to a diameter of the brushless DC motor is larger than 12 cfm/mm.

18. The handheld blower according to claim 16 , wherein along

Assignees

• Chervon Hk Ltd

Inventors

• Yamaoka toshinari
• Shao Xiandian
• Nie Fangjie
• Guo Jianpeng

Classifications

• F04D25/08

  the working fluid being air, e.g. for ventilation · CPC title

• A01G20/43 Primary

  for sweeping, collecting or disintegrating lawn debris · CPC title

• F04D29/545

  Ducts · CPC title

• F04D29/522

  especially adapted for elastic fluid pumps · CPC title

• A01G20/47 Primary

  Vacuum or blower devices · CPC title