Granted Patent B2

US 12,690,515 · App. 17/855,151 · Granted Jul 28, 2026

Inventor: Beth E. Cholst (Wauwatosa, WI)

Assignee: Milwaukee Electric Tool Corporation

A01D34/4165

Abstract

Claims (36)

1 . A trimmer head for use with a string trimmer including a drive shaft, the trimmer head comprising:

a housing rotatable about a rotational axis, the housing including a main body defining a cavity, and a cap removably coupled to the main body, wherein the main body comprises a base wall and a sidewall extending from an inner surface of the base wall;

a spool supported in the cavity and operable to support a line to be dispensed;

a retainer coupled to the housing and the spool, wherein at least a portion of the retainer is positioned between the spool and the cap;

a connection member positioned within the housing and configured to drivingly couple to the drive shaft; and

a plate removably coupled to an outer surface of the base wall opposite the inner surface, wherein the plate can be changed or adjusted plate positions or locations within an outer perimeter of the base wall, and wherein a longitudinal surface of the plate on the outer surface of the base wall is configured to provide additional mass to the trimmer head such that vibration and imbalance of the trimmer head is reduced.

2 . The trimmer head of claim 1 , wherein the housing includes a boss configured to receive the connection member.

3 . The trimmer head of claim 1 , further comprising a biasing member supported in the cavity adjacent the spool.

4 . The trimmer head of claim 1 , wherein the connection member is configured to rotatably and axially fix the main body and the cap to the drive shaft.

5 . The trimmer head of claim 1 , wherein the connection member is positioned in the base wall.

6 . The trimmer head of claim 1 , wherein:

the cap comprises an outer wall and an outer rim extending from the outer wall; and

wear rings are coupled to the outer wall about the rotational axis.

7 . A trimmer head for use with a string trimmer, the trimmer head comprising:

a housing rotatable about a rotational axis, the housing including a main body defining a cavity, and a cap removably coupled to the main body, wherein the main body comprises a base wall and a sidewall extending from an inner surface of the base wall;

a spool supported in the cavity and operable to support a line to be dispensed;

a retainer coupled to the housing and the spool, wherein at least a portion of the retainer is positioned between the spool and the cap; and

a weighted plate coupled to an outer surface of the base wall opposite the inner surface, wherein the weight plate can be changed or adjusted plate positions or locations within an outer perimeter of the base wall, and wherein a longitudinal surface of the weighted plate on the outer surface of the base wall is configured to provide additional mass to the trimmer head such that vibration and imbalance of the trimmer head is reduced.

8 . The trimmer head of claim 7 , wherein the weighted plate is positioned adjacent to the rotational axis.

9 . The trimmer head of claim 7 , wherein the weighted plate is composed of a metallic material.

10 . The trimmer head of claim 7 , wherein the weighted plate is rectangular.

11 . A string trimmer comprising:

a shaft;

a handle positioned on the shaft and including a grip graspable by a user;

a motor housing positioned on the shaft;

a motor positioned within the motor housing and defining a drive shaft; and

a trimmer head removably coupled to the drive shaft, the trimmer head including:

a housing rotatable about a rotational axis, the housing comprising a main body defining a cavity and a cap removably coupled to the main body, the main body comprising a base wall and a sidewall extending from an inner surface of the base wall,

a spool supported in the cavity and operable to support a line to be dispensed,

a connection member positioned within the housing and configured to drivingly couple to the drive shaft, and

a weighted plate coupled to an outer surface of the base wall of the housing opposite the inner surface, wherein the weighted plate can be changed or adjusted plate positions or locations within an outer perimeter of the base wall, and wherein a longitudinal surface of the weighted plate on the outer surface of the base wall is configured to provide additional mass to the trimmer head such that vibration and imbalance of the trimmer head is reduced.

12 . The string trimmer of claim 11 , wherein the trimmer head includes a retainer coupled to the housing and the spool, wherein at least a portion of the retainer is positioned between the spool and the cap, wherein the retainer comprising a ring defining a central opening and retainer arms extending from the ring, and wherein the retainer arms engage retainer openings disposed in the main body of the housing for connecting the main body and the retainer.

13 . The string trimmer of claim 11 , wherein the trimmer head includes a biasing member supported in the cavity adjacent the spool.

14 . The trimmer head of claim 11 , wherein the housing includes a boss configured to receive the connection member.

15 . The trimmer head of claim 11 , wherein the connection member is configured to rotatably and axially fix the main body and the cap to the drive shaft.

16 . The trimmer head of claim 11 , wherein the connection member is positioned in the base wall.

Assignments (1)

Continuity (2)

References Cited (400)