Hand-held work implement having an internal combustion engine and an air filter

Patent metadata

Field	Value
Publication number	US-9322370-B2
Application number	US-201313898517-A
Country	US
Kind code	B2
Filing date	May 21, 2013
Priority date	May 21, 2012
Publication date	Apr 26, 2016
Grant date	Apr 26, 2016

Abstract

A hand-held working implement comprises an internal combustion engine, an air filter, and an intermediate flange, wherein the intermediate flange is arranged between the air filter and the internal combustion engine, wherein the bottom of the intermediate flange is arranged opposite the air filter bottom, wherein the air filter bottom and the intermediate flange bound an interior space, wherein the interior space comprises a portion of the duct, wherein a portion of the duct in the interior space is bounded by at least one boundary wall which protrudes into the interior space transversely with respect to the air filter bottom, wherein the boundary wall is formed integrally on the intermediate flange and/or on the air filter bottom, and wherein the boundary wall bridges the spacing between the air filter bottom and the bottom of the intermediate flange.

First claim

The invention claimed is:

1. A hand-held work implement comprising
an internal combustion engine,
an air filter,
wherein the air filter comprises a filter element which is connected in a fixed manner on its end sides to end plates, wherein the filter element is cylindrical, wherein the filter element and the end plates create a separation between a dirty side and a pure side of the air filter, wherein the pure side of the air filter is connected via a duct to the internal combustion engine, and wherein a first end plate is configured as an air filter bottom, and
an intermediate flange,
wherein the intermediate flange is arranged between the air filter and the internal combustion engine, wherein the bottom of the intermediate flange is arranged opposite the air filter bottom, wherein the air filter bottom and the intermediate flange bound an interior space, wherein the interior space comprises a portion of the duct, wherein a portion of the duct in the interior space is bounded by at least one boundary wall which protrudes into the interior space transversely with respect to the air filter bottom, wherein the boundary wall is formed integrally on the intermediate flange and/or on the air filter bottom, wherein the boundary wall bridges the spacing between the air filter bottom and the bottom of the intermediate flange, wherein at least two seals are molded on the air filter bottom, wherein the two seals bear against the intermediate flange and seal the interior space, wherein a first seal bears against the intermediate flange in a transverse direction with respect to the longitudinal center axis of the filter element and seals in the radial direction, wherein a second seal bears against the intermediate flange in the direction of the longitudinal center axis and seals in the direction of the longitudinal center axis, wherein the first seal and second seal are designed as sealing lips, wherein the air filter bottom is composed of a dimensionally stable plastic, wherein the first seal and the second seal are composed of an elastic material, wherein the first seal and second seal are connected and are injection molded on the air filter bottom.

2. The hand-held work implement according to claim 1 , wherein at least one boundary wall is formed integrally on the intermediate flange.

3. The hand-held work implement according to claim 1 , wherein the intermediate flange comprises a circumferential step, wherein one of the at least two seals bears against the circumferential step.

4. The hand-held work implement according to claim 1 , wherein one of the at least two seals bounds a portion of the wall of the duct.

5. The hand-held work implement according to claim 1 , wherein the intermediate flange comprises a circumferential edge, wherein the air filter bottom is pushed at least partially into the intermediate flange.

6. The hand-held work implement according to claim 1 ,
wherein a first web is arranged on the boundary wall, wherein two further webs are arranged on a component adjacent to the top of the boundary wall, wherein the two further webs follow the path of the boundary wall, and wherein the first web arranged at the boundary wall engages between the two webs arranged adjacent to the top of the boundary wall so that the first web and the two further webs form a labyrinth seal.

7. The hand-held work implement according to claim 1 , further comprising a second end plate, wherein a third seal is molded on a second end plate, wherein the third seal bears against a fastening dome which is formed on the intermediate flange, and wherein a fastening element of an air filter cover protrudes through the third seal.

8. The hand-held work implement according to claim 1 , wherein the pure side of the air filter is connected via an air duct and a mixture duct to the internal combustion engine, wherein a portion of the air duct and a portion of the mixture duct are arranged in the interior space, and wherein the mixture duct comprises at least one fuel opening for feeding fuel into the mixture duct.

9. The hand-held work implement according to claim 8 , wherein the air duct and the mixture duct are arranged independently in a single plane of the interior space, wherein the plane lies transversely with respect to the longitudinal center axis of the filter element.

10. The hand-held work implement according to claim 8 ,
further comprising a mixture duct opening arranged on the intermediate flange through which the mixture duct is guided,
further comprising an air duct opening arranged on the intermediate flange through which the air duct is guided,
wherein a dividing wall separates the mixture duct opening and the air duct opening.

11. The hand-held work implement according to claim 10 , wherein the air filter bottom comprises a closed configuration in the regions which lie opposite the mixture duct opening and the air duct opening.

12. The hand-held work implement according to claim 8 , wherein the air filter bottom comprises a passage opening which connects both the mixture duct and the air duct to the pure side of the air filter.

13. The hand-held work implement according to claim 8 , wherein a portion of the mixture duct and a portion of the air duct are arranged in an intake duct of a carburetor, wherein the intake duct in the carburetor comprises an at least partially round cross section divided by a dividing wall, wherein the dividing wall divides the mixture duct and the air duct.

14. The hand-held work implement according to claim 13 , wherein the intermediate flange is arranged on the carburetor.

15. The hand-held work implement according to claim 1 , wherein a third seal is molded on the air filter bottom on the side which faces away from the intermediate flange, wherein a circumferential wall of an air filter cover bears against the third seal, and wherein the third seal seals the dirty side of the air filter on the air filter bottom with respect to the surroundings.

16. The hand-held work implement according to claim 1 , further comprising an air duct and a mixture duct, wherein the lengths of air duct and mixture duct are independently set such that the pressure waves which are produced in the mixture duct and in the air duct during operation of the hand-held work implement oscillate with the same phase.

17. The hand-held work implement according to claim 8 , wherein the lengths of air duct and mixture duct are independently set such that the pressure waves which are produced in the mixture duct and in the air duct during operation of the hand-held work implement oscillate with the same phase.

18. A hand-held work implement comprising
an internal combustion engine,
an air filter,
wherein the air filter comprises a filter element which is connected in a fixed manner on its end sides to end plates, wherein the filter element is cylindrical, wherein the filter element and the end plates create a separation between a dirty side and a pure side of the air filter, wherein the pure side of the air filter is connected via a duct to the internal combustion engine, and wherein a first end plate is configured as an air filter bottom, and
an intermediate flange,
wherein the intermediate flange is arranged between the air filter and the internal combustion engine, wherein the bottom of the intermediate flange is arranged opposite the air filter bottom, wherein the air filter bottom and the intermediate flange bound an interior space, wherein the interior space comprises a portion of the duct, wherein a portion of the duct in the interior space is bounded by at least one bo

Assignees

• Stihl Ag & Co Kg Andreas

Inventors

• Von Krane Florian
• Rögele Steffen

Classifications

• F02M35/02483

  Cylindrical, conical, oval, spherical or the like filter elements; wounded filter elements · CPC title

• F02B63/02

  for hand-held tools · CPC title

• F02M35/0207 Primary

  on the clean air side · CPC title

• F02M35/10144 Primary

  Connections of intake ducts to each other or to another device · CPC title

• F02M35/1017

  Small engines, e.g. for handheld tools, or model engines; Single cylinder engines · CPC title