Multi-mode trimmer head

Patent metadata

Field	Value
Publication number	US-10517210-B2
Application number	US-201715439561-A
Country	US
Kind code	B2
Filing date	Feb 22, 2017
Priority date	Feb 22, 2016
Publication date	Dec 31, 2019
Grant date	Dec 31, 2019

Abstract

A multi-mode trimmer head for use with an outdoor handheld tool such as a string trimmer, brush cutter, or the like is provided. The trimmer head includes an upper housing, lower housing, bump head, spool, and a spring. The spool includes a first pair of apertures configured to receive a pair of flexible trimmer lines to provide a bump-feed operating mode for the trimmer head. The spool also includes a separate, second pair of apertures configured to receive a single fixed-line trimmer line to provide a fixed-line operating mode for the trimmer head. The trimmer head is switchable between the fixed-line operating mode and the bump-feed operating mode without the need to disassemble the trimmer head.

First claim

What is claimed is:

1. A multi-mode trimmer head releasably attachable to an outdoor handheld tool, said multi-mode trimmer head comprising:
an upper housing;
a lower housing releasably attached to said upper housing to form a casing, wherein said casing includes a pair of first apertures and a pair of second apertures;
a spool positioned between said upper and lower housings, said spool having a central plate and a pair of guide channels formed into said central plate, and each of said guide channels includes a first passage and a second passage; and
a bump head attached to said spool and extending from said lower housing for use in a bump-feed operating mode;
wherein said first passages are configured to operate the trimmer head with a fixed-line trimmer line in a fixed-line operating mode, and each of said second passages is configured to operate said trimmer head with separate bump-line trimmer line in said bump-feed operating mode.

2. The multi-mode trimmer head of claim 1 , wherein said central plate includes a portion extending radially outward from a wall defining a central bore and a portion extending radially inward from said wall defining said central bore wherein a portion of said central plate is located within said central bore, a pair of winding apertures and a pair of holding apertures are formed into said portion of said central plate extending radially outward from said wall defining said central bore, and each of said guide channels is connected to one of said pair of winding apertures and one of said pair of holding apertures.

3. The multi-mode trimmer head of claim 2 , wherein said first passage of each of said guide channel extends between one of said pair of winding apertures and one of said pair of holding apertures.

4. The multi-mode trimmer head of claim 1 , wherein each of said guide channels includes a junction corner which separates said first passage from said second passage.

5. The multi-mode trimmer head of claim 4 , wherein said second passage includes a holding corner that defines a narrowed entrance into a holding volume.

6. The multi-mode trimmer head of claim 1 , wherein said central plate includes a portion extending radially outward from said wall defining said central bore and a portion extending radially inward from said wall defining said central bore wherein a portion of said central plate is located within said central bore, and said spool also includes an upper plate and a lower plate, said upper and lower plates extending radially outward from said wall defining said central bore and positioned adjacent to opposite sides of said central plate.

7. The multi-mode trimmer head of claim 1 further comprising a cover ring positioned immediately adjacent to said guide channels for enclosing said guide channels.

8. The multi-mode trimmer head of claim 7 , wherein said cover ring includes a pair of cantilevered tabs, wherein each of said cantilevered tabs extend into separate guide channels.

9. A multi-mode trimmer head releasably attachable to an outdoor handheld tool, said multi-mode trimmer head comprising:
a casing having an upper housing and a lower housing, wherein said lower housing is releasably attached to said upper housing;
a pair of opposing first apertures formed through said casing;
a pair of second apertures formed through said casing, said second apertures positioned adjacent to each other;
a spool positioned between said upper and lower housings, said spool having a wall defining a central bore therewithin and a central plate having both a portion extending radially outward from said wall defining said central bore and a portion positioned within said central bore that extends radially inward from said wall defining said central bore, said spool further including a pair of guide channels formed into said central plate, each of said guide channels includes a winding aperture formed into said central plate at one end and a holding aperture formed into said central plate at an opposing end, and an entrance into a holding volume wherein said winding apertures are alignable with said first apertures of said casing and said holding apertures are alignable with said second apertures of said casing; and
a bump knob attached to said spool and extending downwardly from said lower housing;
wherein the pair of second apertures and holding apertures are configured to operate the trimmer head with a fixed-line trimmer line in a fixed-line operating mode, and the winding apertures and the entrance into the holding volume are configured to operate the trimmer head with a pair of bump-line trimmer lines in a bump-feed operating mode.

10. The multi-mode trimmer head of claim 9 further comprising a cover ring positioned within said central bore and immediately adjacent to said guide channels for enclosing said guide channels.

11. The multi-mode trimmer head of claim 9 , wherein rotation of said bump knob causes said spool to rotate within said casing.

12. The multi-mode trimmer head of claim 9 , wherein each of said first and second guide channels includes a first passage and a second passage.

13. The multi-mode trimmer head of claim 9 , wherein said winding apertures are positioned on opposite sides of said spool and said holding apertures are positioned adjacent to each other between said winding apertures.

Assignees

• Mtd Products Inc

Inventors

• Cabrera Oscar
• Johnson Robert

Classifications

• A01D34/4166 Primary

  Mounting or replacement of the lines · CPC title

• A01D34/416

  Flexible line cutters · CPC title

• A01D34/4163

  by triggered line feedout, e.g. bump-feeding · CPC title

• A01D34/733

  Cutting-blade mounting means · CPC title