Trimmer Head With Improved Line Release Feature

Patent metadata

Field	Value
Publication number	US-2020315089-A1
Application number	US-201816768114-A
Country	US
Kind code	A1
Filing date	Nov 19, 2018
Priority date	Nov 30, 2017
Publication date	Oct 8, 2020
Grant date	—

Abstract

A trimmer head of a hand-held cutting device may include a spool onto which trimmer line is loadable and from which the trimmer line is dispensable, a housing including a first housing portion and a second housing portion operably coupled to the first housing portion to house the spool where the housing is driven rotationally about an axis by a shaft during powered operation of the device, a coupling assembly configured to selectively couple the spool to and decouple the spool from the housing during powered operation of the device based on an axial position of the coupling assembly within the housing, and a button operably coupled to the coupling assembly to alter the axial position of the coupling assembly when the button is moved out of a rest position by a bump of the button on a surface.

First claim

1 . A trimmer head for a hand-held cutting device, the trimmer head comprising:
a spool onto which trimmer line is loadable and from which the trimmer line is dispensable; a housing including a first housing portion and a second housing portion operably coupled to the first housing portion to house the spool, the housing being driven rotationally about an axis by a shaft during powered operation of the device; a coupling assembly configured to selectively couple the spool to and decouple the spool from the housing during powered operation of the device based on an axial position of the coupling assembly within the housing; and a button operably coupled to the coupling assembly to alter the axial position of the coupling assembly when the button is moved out of a rest position by a bump of the button on a surface.

2 . The trimmer head of claim 1 , wherein the coupling assembly is configured to prevent relative motion between the spool and the housing when the button is in the rest position during powered operation of the device, and enable relative motion between the spool and the housing when the button is displaced from the rest position.

3 . The trimmer head of claim 1 , wherein the spool comprises a line channel extending across the axis.

4 . The trimmer head of claim 1 , wherein the coupling assembly comprises a driver configured to transfer rotational movement to the spool.

5 . The trimmer head of claim 4 , wherein the driver is rotationally fixed to the spool.

6 . (canceled)

7 . The trimmer head of claim 5 , wherein the driver is axially movable in relation to the spool between a first axial position, in which the driver is rotationally coupled to the housing, and a second axial position, in which the driver is rotationally decoupled from the housing.

8 . The trimmer head of claim 4 , wherein the driver is sliding engagement with the spool,
wherein the driver comprises at least one protrusion offset from the axis, and wherein the at least one protrusion rotationally couples the driver to the spool.

9 . (canceled)

10 . The trimmer head of claim 4 , wherein the driver comprises a pair of protrusions offset from the axis, wherein the pair of drive protrusions straddle the channel.

11 . The trimmer head of claim 4 , wherein the coupling assembly comprises a biasing member, wherein the biasing member is disposed between the second housing portion and the button to bias the button toward the rest position, and
wherein the second housing portion comprises an axial orifice through which a stem of the driver passes to operably couple the driver to the button.

12 . (canceled)

13 . The trimmer head of claim 4 , wherein the second housing portion comprises a base plate that extends substantially perpendicular to the axis, and wherein the driver comprises a base that lies in a plane parallel to a plane in which the base plate lies.

14 . The trimmer head of claim 13 , wherein the base plate comprises a plurality of protrusions extending away from a surface of the base plate toward the first housing portion, wherein the base comprises a plurality of projections extending toward the base plate, and wherein the projections and protrusions interact with each other to transfer movement of the housing to the driver responsive to the button being in the rest position during powered operation of the trimmer, and interact with each other to enable loading the trimmer line onto the spool by manual rotation of the spool and driver via the button when the trimmer is not powered.

15 . The trimmer head of claim 14 , wherein each of the projections comprises a sloped face configured to face a corresponding and complementary angled face of the protrusions to enable the manual rotation of the spool and driver via the button when the trimmer is not powered.

16 . The trimmer head of claim 14 , wherein each of the projections comprises a perpendicular face configured to face a corresponding perpendicular face of the protrusions to transfer rotation of the housing to the spool via the driver during powered operation of the trimmer.

17 . The trimmer head of claim 1 , wherein the spool comprises a plate extending substantially perpendicular to the axis between sidewalls of a hub of the spool, and wherein one or more knife receptors are disposed in the plate to enable a corresponding one or more knife members of the driver to pass therethrough.

18 . The trimmer head of claim 17 , wherein the knife members slidingly engage the knife receptors to enable the driver to maintain a rotational alignment with the spool regardless of an axial position of the driver relative to the spool.

19 . The trimmer head of claim 1 , wherein the spool and the housing do not move axially, and the coupling assembly is in contact with the housing and spool to maintain rotational alignment between the housing and the spool when the button is in the rest position during powered operation of the trimmer, and wherein the coupling assembly enables relative rotational motion between the spool and the housing when the button is displaced from the rest position.

20 . The trimmer head of claim 19 , wherein the relative rotational motion between the spool and the housing moves the spool in an unwinding direction relative to the housing to dispense the trimmer line from the spool.

21 . (canceled)

22 . The trimmer head of claim 1 , wherein the second housing portion comprises an axial orifice, and the button has a radial width exceeding a radial width of the axial orifice.

23 . The trimmer head, wherein the housing is configured to be directly coupled to a drive shaft.

24 - 35 . (canceled)

36 . A hand-held cutting device comprising:
an elongated member graspable along a portion thereof by an operator; a trimmer head disposed at one end of the elongated member and configured to be rotatable to perform a cutting function using trimmer line that extends from the trimmer head; and a power unit operably coupled to the trimmer head to selectively cause rotation of the trimmer head via turning a shaft that defines an axis of the trimmer head during powered operation of the device, wherein the trimmer head is a trimmer head as defined in claim 1 .

Assignees

• Husqvarna Ab

Inventors

• Racz Joseph
• Wright Michael

Classifications

• A01D34/4163 Primary

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

• A01D34/416 Primary

  Flexible line cutters · CPC title