Filament cutting head for a trimmer

Patent metadata

Field	Value
Publication number	US-10694663-B2
Application number	US-201815975292-A
Country	US
Kind code	B2
Filing date	May 9, 2018
Priority date	May 9, 2017
Publication date	Jun 30, 2020
Grant date	Jun 30, 2020

Abstract

A rotatingly drivable filament cutting head for a trimmer, having a basic body on which a cutting filament is held. The cutting filament extends from outside the basic body through an opening into an interior region of the filament cutting head open to the surrounding area. A stop is arranged on the filament cutting head, so that, in a first position of the cutting filament, the stop delimits a filament portion of the cutting filament, which is insertable into the interior region, to an insertion length. A deflection element is arranged in the interior region so that the cutting filament can be switched from its first position, without the cutting filament being longitudinally displaced, into a second position. The cutting filament abuts against the deflection element in its second position and the stop does not delimit the length of the filament portion which is insertable into the interior region.

First claim

We claim:

1. A filament cutting head for a trimmer, wherein the filament cutting head is rotatingly drivable about a rotational axis in operation, the filament cutting head comprising: a body that defines an interior region that is open to an area surrounding the housing, the body having a filament opening; at least one cutting filament insertable into and held in the housing so that the cutting filament extends from an outside of the body through the filament opening into the interior region of the body; a stop attached to the body so as to be in the interior region, wherein, in a first position of the cutting filament, the stop delimits a length of a filament portion of the cutting filament that extends into the interior region to an insertion length; and at least one deflection element arranged in the interior region of the body so that the filament portion of the cutting filament is bendable from the first position, without the cutting filament being displaced in a longitudinal direction of the cutting filament, into a second position in which the cutting filament abuts against the deflection element and the stop does not delimit the length of the filament portion which is inserted into the interior region.

2. The filament cutting head according to claim 1 , wherein in the first position of the cutting filament, the filament portion of the cutting filament is aligned in a first direction, and the stop lies along the first direction, and in the second position of the cutting filament, the filament portion of the cutting filament is aligned in a second direction, wherein the stop lies outside a longitudinal axis of the filament portion of the cutting filament aligned in the second direction.

3. The filament cutting head according to claim 2 , wherein, when viewed in a direction of the rotational axis, the deflection element is offset transversely with respect to the first direction in relation to the cutting filament.

4. The filament cutting head according to claim 2 , wherein the filament portion in the first direction and the filament portion in the second direction enclose an angle of at least 5° around the rotational axis of the filament cutting head.

5. The filament cutting head according to claim 2 , wherein the filament portion in the first direction and the filament portion in the second direction enclose an angle of at least 5° in a plane which includes the rotational axis and extends parallel to a longitudinal axis of the cutting filament.

6. The filament cutting head according to claim 1 , wherein the filament opening has a lower opening edge in the interior region, and the deflection element has a support, wherein the cutting filament abuts against both the lower opening edge and the support in the second position.

7. The filament cutting head according to claim 6 , wherein a distance measured in a direction of the rotational axis between the support and the lower opening edge is smaller than a height of the filament opening measured in the direction of the rotational axis.

8. The filament cutting head according to claim 6 , wherein the support of the deflection element comprises a locking contour configured to secure the abutting cutting filament in the second position.

9. The filament cutting head according to claim 1 , wherein a distance between the filament opening and the stop is no more than 10 times a diameter of the cutting filament.

10. The filament cutting head according to claim 1 , wherein a distance between the filament opening and the stop is at least 3 times a diameter of the cutting filament.

11. The filament cutting head according to claim 1 , further comprising a screening wall arranged in the interior region of the housing next to the cutting filament in a rotational direction of the rotational axis.

12. The filament cutting head according to claim 11 , wherein the screening wall extends from the filament opening to the stop.

13. The filament cutting head according to claim 1 , wherein the body has an underside which faces ground during operation, wherein the underside defines the interior region so that the interior region is open toward the surrounding area.

14. The filament cutting head according to claim 13 , wherein a distance measured in a direction of the rotational axis between the underside and an inner end of the cutting filament is greater in the first position than in the second position.

15. The filament cutting head according to claim 1 , wherein the deflection element is a ramp.

Assignees

• Stihl Ag & Co Kg Andreas

Inventors

• Lang Sven
• Günther David

Classifications

• A01D34/4166 Primary

  Mounting or replacement of the lines · CPC title

• A01D34/4168 Primary

  Constructional details of the flexible lines · CPC title

• A01D34/4165

  Mounting of the cutter head · CPC title

• A01D34/416

  Flexible line cutters · CPC title

• A01D34/4167

  Protection devices · CPC title