Grass trimmer

Patent metadata

Field	Value
Publication number	US-11219159-B2
Application number	US-201916693725-A
Country	US
Kind code	B2
Filing date	Nov 25, 2019
Priority date	Nov 25, 2014
Publication date	Jan 11, 2022
Grant date	Jan 11, 2022

Abstract

A grass trimmer includes a cutting head for mounting a cutting member, a drive head having a output shaft for driving the cutting head to rotate, and an anti-winding member for preventing the output shaft from being wound to by grass. The drive head includes a drive device to drive the output shaft and a head housing for accommodating the drive device. The output shaft connects to the cutting head and passes through the anti-winding member and the anti-winding member is mounted to the cutting head so as to rotate with the cutting head and is disposed between the cutting head and the head housing so as to fill the space between the cutting head and the head housing.

First claim

What is claimed is:

1. A grass trimmer, comprising:
a cutting head supporting a cutting member;
a drive head having an output shaft driving the cutting head to rotate;
a power source device providing power to the drive head;
a connector connecting the drive head and the power source device; and
an anti-winding member adapted to prevent an object being cut by the cutting member from winding around the output shaft;
wherein the drive head comprises:
a motor driving the output shaft; and
a head housing accommodating the motor;
wherein the cutting head forms a mounting hole and has a top end which is contacted with the anti-winding member,
wherein the anti-winding member forms a center hole accepting the output shaft which is inserted into the mounting hole and the anti-winding member is mounted to the cutting head so as to rotate with the cutting head and is disposed between the cutting head and the head housing so as to fill a space between the cutting head and the head housing,
wherein the anti-winding member includes at least two fixing holes, the cutting head includes at least two fixing apertures, and the grass trimmer further comprises a plurality of fastening elements mounted to a corresponding one of the at least two fixing holes and one of the at least two fixing apertures thereby fixing the anti-winding member to the cutting head,
wherein the cutting head comprises a plurality of top ribs formed at the top end of the cutting head and the anti-winding member is connected to the plurality of top ribs, and
wherein the at least two fixing apertures are disposed on the plurality of top ribs.

2. The grass trimmer of claim 1 , wherein one or more of the plurality of top ribs include a locating lug, the anti-winding member includes a plurality of locating holes, and the locating lug is inserted into a corresponding one of the plurality of locating holes so as to maintain a relative location between the anti-winding member and the cutting head.

3. The grass trimmer of claim 1 , wherein the anti-winding member comprises a peripheral surface and a plurality of peripheral ribs, the plurality of peripheral ribs protrude from the peripheral surface, and, when the anti-winding member rotates with the cutting head, both the plurality of peripheral ribs and the plurality of top ribs generate centrifugal airflow.

4. The grass trimmer of claim 1 , wherein the anti-winding member is an annular shaped member.

5. The grass trimmer of claim 1 , wherein the drive head further comprises a fan blowing airflow to the anti-winding member and the fan is disposed in the head housing and driven by the motor.

6. The grass trimmer of claim 5 , wherein the motor comprises a stator connected to the head housing and a rotor for rotating with the output shaft relative to the stator wherein the rotor comprises a sleeve for accommodating the stator and the fan is mounted with the sleeve so as to rotate with the sleeve.

7. The grass trimmer of claim 6 , wherein the fan is an axial fan which is disposed on an end of the sleeve away from the cutting head.

8. The grass trimmer of claim 7 , wherein the power source device comprises a device housing for accommodating or connecting to a battery, the connector is provided with a connecting air flue connecting an inner space of the head housing to an inner space of the device housing and the device housing is provided with an air vent.

Assignees

• Chervon Hk Ltd

Inventors

• Yuan Feng
• Peng Ming
• Guo Jianpeng
• Tang Zichun

Classifications

• A01D34/90

  for carrying by the operator · CPC title

• A01D34/416

  Flexible line cutters · CPC title

• A01D34/4167 Primary

  Protection devices · CPC title

• B25F5/008

  Cooling means · CPC title

• A01D34/4165 Primary

  Mounting of the cutter head · CPC title