Blower wheel and power tool with an internal combustion engine and a blower wheel

Patent metadata

Field	Value
Publication number	US-11268534-B2
Application number	US-201615376717-A
Country	US
Kind code	B2
Filing date	Dec 13, 2016
Priority date	Dec 15, 2015
Publication date	Mar 8, 2022
Grant date	Mar 8, 2022

Abstract

A blower wheel is provided with a base member having an axis of rotation and with a rotor of a generator, wherein the rotor is fixedly secured on the blower wheel. At least one magnet is arranged on the rotor. An inertia ring is fixedly secured on the base member at a spacing to the at least one magnet. The inertia ring is made of a first material having a first density and the base member is made of a second material having a second density. The first density is greater than the second density. An internal combustion engine is provided with such a blower wheel.

First claim

What is claimed is:

1. A blower wheel comprising:
a base member having an axis of rotation;
a rotor of a generator, wherein the rotor is fixedly secured on the blower wheel;
at least one magnet arranged on the rotor;
an inertia ring fixedly secured on the base member at a spacing to the at least one magnet;
wherein the inertia ring is made of a first material having a first density and wherein the base member is made of a second material having a second density;
wherein the first density is greater than the second density.

2. The blower wheel according to claim 1 , wherein the inertia ring comprises at least one section in which a thickness of the inertia ring measured in a direction of the axis of rotation decreases in a radial outward direction relative to the axis of rotation.

3. The blower wheel according to claim 1 , wherein the inertia ring is attached by an adhesive to the base member.

4. The blower wheel according to claim 1 , wherein the rotor is fixedly secured on the base member of the blower wheel.

5. The blower wheel according to claim 1 , wherein the inertia ring is a closed continuous ring extending concentrically about the axis of rotation of the base member.

6. The blower wheel according to claim 1 , further comprising a metallic magnetic return ring configured to reinforce a magnetic flux of the at least one magnet.

7. The blower wheel according to claim 6 , wherein the inertia ring is arranged radially outside of the metallic magnetic return ring in a radial direction relative to the axis of rotation.

8. The blower wheel according to claim 1 , wherein the base member comprises an annular wall arranged on one side of the base member, wherein the annular wall extends in an annular shape about the axis of rotation, and wherein the at least one magnet is arranged radially inside the annular wall in a radial direction relative to the axis of rotation.

9. The blower wheel according to claim 8 , wherein the inertia ring is arranged outside of the annular wall in the radial direction.

10. The blower wheel according to claim 1 , wherein the base member comprises a first side and a second side, wherein the first side and the second side face in opposite axial directions relative to the axis of rotation, and further comprises flow guiding elements that are arranged on the second side of the base member.

11. The blower wheel according to claim 10 , wherein the inertia ring is arranged on the first side of the base member.

12. The blower wheel according to claim 10 , wherein the flow guiding elements are arranged in a circular ring area of the base member, wherein the circular ring area has a center point positioned on the axis of rotation, wherein an inner radius of the circular ring area corresponds to at most 0.5 times an outer radius of the base member, wherein an outer radius of the circular ring area corresponds to at least 0.9 times the outer radius of the base member.

13. A blower wheel comprising:
a base member having an axis of rotation;
a rotor of a generator, wherein the rotor is fixedly secured on the blower wheel;
at least one magnet arranged on the rotor;
an inertia ring fixedly secured on the base member at a spacing to the at least one magnet;
wherein the inertia ring is made of a first material having a first density and wherein the base member is made of a second material having a second density;
wherein the first density is greater than the second density;
wherein the base member comprises a first side and a second side, wherein the first side and the second side face in opposite axial directions relative to the axis of rotation, and further comprises flow guiding elements that are arranged on the second side of the base member;
wherein the base member has an imaginary terminal plane positioned perpendicular to the axis of rotation, wherein the imaginary terminal plane is arranged on the first side of the base member, wherein the imaginary terminal plane extends through an outermost boundary of the base member provided in the axial direction, wherein the base member on the second side of the base member comprises a flow guiding surface, and wherein a first measured spacing of the flow guiding surface, measured relative to the imaginary terminal plane, increases as a second measured spacing of the flow guiding surface, measured in a radial direction relative to the axis of rotation, decreases.

14. The blower wheel according to claim 13 , wherein the rotor is fixedly secured on the base member of the blower wheel.

15. The blower wheel according to claim 13 , wherein the inertia ring is a closed continuous ring extending concentrically about the axis of rotation of the base member.

16. The blower wheel according to claim 13 , wherein, on a side of the inertia ring that is facing the flow guiding surface, a contour of the inertia ring follows a contour of the flow guiding surface.

17. The blower wheel according to claim 13 , wherein, between the first side and the second side of the base member, a separating wall is arranged and wherein the inertia ring is arranged adjacent to the separating wall.

18. The blower wheel according to claim 17 , wherein the flow guiding surface is formed at least partially by the separating wall of the base member.

19. The blower wheel according to claim 17 , wherein a contour of the separating wall on the first side of the base member follows a contour of the flow guiding surface on the second side of the base member.

20. A power tool comprising:
an internal combustion engine;
a blower wheel comprising:
a base member having an axis of rotation;
a rotor of a generator, wherein the rotor is fixedly secured on the blower wheel;
at least one magnet arranged on the rotor;
an inertia ring fixedly secured on the base member at a spacing to the at least one magnet, wherein the inertia ring is made of a first material having a first density and the base member is made of a second material having a second density, wherein the first density is greater than the second density.

21. The power tool according to claim 20 , wherein the rotor is fixedly secured on the base member of the blower wheel.

22. The power tool according to claim 20 , wherein the inertia ring is a closed continuous ring extending concentrically about the axis of rotation of the base member.

Assignees

• Stihl Ag & Co Kg Andreas

Inventors

• Wolf Andreas
• Weissert Wolfgang
• Lempges Volker
• Zimmermann Helmut
• Wolf Günter
• Vollmer Holger
• Förster Marcel
• Dawin Ute
• Lank Jonas

Classifications

• H02K2213/03

  Machines characterised by numerical values, ranges, mathematical expressions or similar information · CPC title

• F04D29/668

  damping or preventing mechanical vibrations · CPC title

• F04D29/281 Primary

  for fans or blowers · CPC title

• F04D29/624

  especially adapted for elastic fluid pumps · CPC title

• F02B63/02

  for hand-held tools · CPC title