Mowing Head for a Trimmer

Patent metadata

Field	Value
Publication number	US-2019230851-A1
Application number	US-201916378596-A
Country	US
Kind code	A1
Filing date	Apr 9, 2019
Priority date	Aug 12, 2015
Publication date	Aug 1, 2019
Grant date	—

Abstract

A mowing head for a trimmer is rotated about an axis of rotation when operated and has a housing with a circumferential wall. A fastening device with a trimmer line guide with a trimmer line channel is provided for the trimmer line. The trimmer line channel has a clamping section with a longitudinal direction. The clamping section has a wide longitudinal side and a narrow longitudinal side, both extending in the longitudinal direction. The clamping section has an inner width tapering from the wide longitudinal side toward the narrow longitudinal side. The trimmer line guide has a deflection edge adjoining the clamping section. The deflection edge is slanted relative to the longitudinal direction such that the deflection edge generates a force component acting on the trimmer line directed toward the narrow longitudinal side when a pulling force is acting on the trimmer line guided through the fastening device.

First claim

What is claimed is:

1 . A mowing head for a trimmer, the mowing head comprising:
an axis of rotation about which the mowing head is driven in rotation when operated; a housing comprising a circumferential wall; at least one fastening device configured to secure a trimmer line on the mowing head, wherein the at least one fastening device comprises a trimmer line guide; the trimmer line guide comprising a first trimmer line channel and the first trimmer line channel comprising a first clamping section; the first clamping section having a first longitudinal direction and comprising a wide longitudinal side extending in the first longitudinal direction and a narrow longitudinal side extending in the first longitudinal direction, wherein the wide longitudinal side and the narrow longitudinal side extend at least partially across a same length section of the first clamping section; the first clamping section comprising an inner width tapering in a direction from the wide longitudinal side toward the narrow longitudinal side; the trimmer line guide comprising a deflection area adjoining the first clamping section; the deflection area comprising a deflection edge that is slanted relative to the first longitudinal direction of the first clamping section such that the deflection edge generates a force component acting on the trimmer line in a direction toward the narrow longitudinal side of the first clamping section when a pulling force is acting on the trimmer line guided through the at least one fastening device; the trimmer line guide further comprising a second trimmer line channel and a partition web disposed between the first trimmer line channel and the second trimmer line channel; the partition web comprising an end face, wherein the end face comprises a surface forming an outer side of the mowing head and wherein the surface forms the deflection edge for the trimmer line.

2 . The mowing head according to claim 1 , wherein the first trimmer line channel has a first sidewall formed on the partition web and the second trimmer line channel has a second sidewall formed on the partition web opposite the first sidewall.

3 . The mowing head according to claim 2 , wherein the first and second sidewalls are approximately parallel to each other.

4 . The mowing head according to claim 1 , wherein the second trimmer line channel comprises a second clamping section having a second longitudinal direction, wherein the first and second longitudinal directions extend approximately parallel to each other.

5 . The mowing head according to claim 1 , wherein the mowing head comprises a conical section, provided with the first and second trimmer line channels and comprising at least partially a conical outer contour, wherein the deflection edge and the conical outer contour of the conical section extend parallel to each other.

6 . The mowing head according to claim 1 , wherein the deflection edge is displaced into the housing relative to an outer contour of the housing.

7 . The mowing head according to claim 1 , wherein first the longitudinal direction of the first clamping section is positioned relative to the deflection edge at an angle of 10° to 80° in a section plane that is parallel to the axis of rotation and that contains the deflection edge, wherein the angle is oriented in a direction toward the first trimmer line channel and opens in a direction toward the narrow longitudinal side of the first clamping section.

8 . The mowing head according to claim 1 , wherein, viewed in a radial direction relative to the axis of rotation, the narrow longitudinal side of the first clamping section of the first trimmer line channel is arranged radially outwardly and the wide longitudinal side is arranged radially inwardly.

9 . The mowing head according to claim 1 , wherein the mowing head further comprises an end face delimiting the mowing head in a direction of the axis of rotation, wherein the first trimmer line channel comprises a deflection contour that deflects the trimmer line guided through the at least one fastening device from the circumferential wall toward the end face.

10 . The mowing head according to claim 1 , wherein the trimmer line guide begins at an inlet opening that is positioned in an entry direction and wherein the trimmer line guide ends at an outlet opening that is positioned in an exit direction.

11 . The mowing head according to claim 10 , wherein the trimmer line guide has a straight entry line extending through the inlet opening and positioned in the entry direction and further has a straight exit line extending through the outlet opening and positioned in the exit direction, wherein the straight entry line and the straight exit line are skew relative to each other.

12 . The mowing head according to claim 1 , wherein the housing comprises at least two housing parts, wherein the at least two housing parts delimit the trimmer line guide and are connected to each other by at least one rivet.

13 . A mowing head for a trimmer, the mowing head comprising:
an axis of rotation about which the mowing head is driven in rotation when operated; a housing comprising a circumferential wall; at least one trimmer line; at least one fastening device comprising a trimmer line guide and securing the at least one trimmer line on the mowing head; the trimmer line guide comprising a first trimmer line channel; the first trimmer line channel comprising a clamping section; the clamping section having a longitudinal direction and comprising a wide longitudinal side extending in the longitudinal direction and a narrow longitudinal side extending in the longitudinal direction, wherein the wide longitudinal side and the narrow longitudinal side extend at least partially across a same length section of the clamping section; the clamping section comprising an inner width tapering in a direction from the wide longitudinal side toward the narrow longitudinal side; the trimmer line guide comprising a deflection area adjoining the clamping section; the deflection area comprising a deflection edge and the at least one trimmer line is guided across the deflection edge; the deflection edge being slanted relative to the longitudinal direction of the clamping section such that the deflection edge generates a force component acting on the at least one trimmer line in a direction toward the narrow longitudinal side of the clamping section when a pulling force is acting on the at least one trimmer line; the trimmer line guide further comprising a second trimmer line channel and a partition web disposed between the first trimmer line channel and the second trimmer line channel; the partition web comprising an end face, wherein the end face comprises a surface forming an outer side of the mowing head and wherein the surface forms the deflection edge for the at least one trimmer line.

14 . The mowing head according to claim 13 , wherein an inner width of the clamping section at the narrow longitudinal side is smaller than a minimum diameter of the at least one trimmer line.

15 . The mowing head according to claim 13 , wherein the mowing head comprises a conical section provided with the first and second trimmer line channels, wherein the conical section comprises at least partially a conical outer contour, wherein the deflection edge is displaced by a displacement into the housing relative to the conical outer contour, and wherein the displacement is at least approximately as large as a diameter of the at least one trimmer line.

Assignees

• Stihl Ag & Co Kg Andreas

Inventors

• Rethaber Achim

Classifications

• A01D34/4165

  Mounting of the cutter head · CPC title

• A01D34/4166 Primary

  Mounting or replacement of the lines · CPC title

• A01D34/90

  for carrying by the operator · CPC title

• A01D34/733

  Cutting-blade mounting means · CPC title

• A01D34/416 Primary

  Flexible line cutters · CPC title