Granted Patent B2

US 12,439,846 · App. 17/723,146 · Granted Oct 14, 2025

Inventors: Beth E. Cholst (Wauwatosa, WI); Troy C. Thorson (Cedarburg, WI)

Assignee: Milwaukee Electric Tool Corporation

A01D34/4168A01D34/4165

Abstract

Claims (23)

1. A 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;

a spool supported in the cavity and operable to support line to be dispensed; a retainer positioned between the housing and the spool;

a first wear ring protruding from a base wall at a distal end of the housing, the first wear ring protruding axially outward from the base wall and opposite of the cavity; and

a second wear ring protruding from the base wall the distal end of the housing, the second wear ring protruding axially outward from the base wall and opposite of the cavity, wherein the second wear ring is concentrically positioned relative to the first wear ring, and

wherein the first and second wear rings define one or more axial maxima from the base wall and prevent damage to the housing.

2. The trimmer head of claim 1 , wherein the first wear ring is rectangular.

3. The trimmer head of claim 1 , wherein the first wear ring is circular.

4. The trimmer head of claim 1 , further comprising a plurality of ribs protruding from the distal end of the main body, wherein the plurality of ribs are positioned between the first wear ring and the second wear ring.

5. The trimmer head of claim 1 , wherein the first wear ring is positioned on the cap.

6. The trimmer head of claim 1 , wherein the first wear ring is integral with the distal end of the housing.

7. The trimmer head of claim 1 , wherein the first wear ring is removably coupled to the distal end of the housing.

8. The trimmer head of claim 1 , wherein one of the main body and the cap includes a chamfered edge.

9. 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, wherein the main body includes a sidewall, a base wall, and a chamfered edge extending between the sidewall and the base wall, and

a cap removably coupled to the main body;

a spool supported in the cavity and operable to support line to be dispensed, wherein the spool is drivingly coupled to the drive shaft;

a retainer positioned between the housing and the spool;

a first wear ring protruding from the base wall of the main body, the first wear ring protruding axially outward from the base wall and opposite of the cavity; and

a second wear ring protruding from the base wall of the main body, the second wear ring protruding from the base wall axially outward and opposite of the cavity, wherein the second wear ring is concentrically positioned relative to the first wear ring, and

wherein the first and second wear rings define one or more axial maxima from the base wall and prevent damage to the housing.

10. The trimmer head of claim 9 , further comprising a plurality of ribs protruding from the base wall of the housing, wherein the plurality of ribs are positioned between the first wear ring and the second wear ring.

Assignments (1)

Continuity (4)

References Cited (400)