Chain saw

Patent metadata

Field	Value
Publication number	US-11524423-B2
Application number	US-202017074566-A
Country	US
Kind code	B2
Filing date	Oct 19, 2020
Priority date	Oct 18, 2019
Publication date	Dec 13, 2022
Grant date	Dec 13, 2022

Abstract

A chain saw has a housing, a guiding plate, a chain, a power system and a tensioning component. The tensioning component includes a knob, a driving member and a transmission assembly. When the chain is in a loose state, the knob is forced to rotate and drives the transmission assembly to rotate, and the transmission assembly drives the driving member to rotate, then the driving member drives the guiding plate to move to tension the chain. When the chain is in an extension state, the knob is forced to rotate, the driving member stays still, and a skidding inside the tensioning component is generated. The tensioning component of the chain saw of the present invention can tension the chain and fix the guiding plate by rotating the knob, the operation is simple and convenient; Meanwhile, the tensioning component avoids over-tensioning the chain by skidding inside.

First claim

What is claimed is:

1. A chain saw, comprising:
a housing;
a guiding plate installed on the housing and being movable forward and backward relatively to the housing;
a chain arranged around the guiding plate;
a power system installed on the housing and driving the chain; and
a tensioning component comprising a knob, a driving member and a transmission assembly arranged between the knob and the driving member;
wherein, when the chain is in a loose state, the knob is forced to rotate and drives the transmission assembly to rotate, the transmission assembly then drives the driving member to rotate, and the driving member drives the guiding plate to move to tension the chain; when the chain is in an extension state, the knob is forced to rotate, the driving member stays still, and a skidding inside the tensioning component is generated;

wherein the transmission assembly comprises a releasing block, an elastic member and a gear set, the releasing block engages with the knob, and the elastic member is arranged between the knob and the releasing block, the releasing block comprises a plurality of inner teeth, and the gear set comprises a plurality of outer teeth; when the chain is in the loose state, the knob drives the releasing block to rotate, and the releasing block drives the gear set to rotate through the cooperation of the inner teeth and the outer teeth, then the gear set drives the driving member to rotate; when the chain is in the extension state, the skidding inside the tensioning component is generated between the inner teeth and the outer teeth; and
wherein the gear set comprises a sun gear pivot mounted on the knob and at least one planetary gear pivot mounted on the driving member, the knob is arranged outside the gear set, and an inner ring gear is arranged on an inner wall of the knob for matching with the at least one planetary gear.

2. The chain saw according to claim 1 , wherein the skidding inside the tensioning component is generated between the transmission assembly and the knob, or between the transmission assembly and the driving member, or between parts of the transmission assembly.

3. The chain saw according to claim 1 , wherein the knob comprises a pin with a thread hole, the housing comprises a bolt passing through the guiding plate, and the pin is in threaded connection with the bolt to fix the tensioning component to the housing; and wherein when the chain is in the extension state, rotating the knob enables the pin tightly pressing the guiding plate.

4. The chain saw according to claim 1 , wherein the knob includes a pin with an end passing through the transmission assembly and the driving member, and the end is sheathed with a retaining ring.

5. The chain saw according to claim 1 , wherein the gear set comprises a bracket arranged outside the planetary gear, at least one gap is arranged on a side wall of the bracket, an outer side of the planetary gear protrudes out of the at least one gap to mesh with the planetary gear.

6. The chain saw according to claim 1 , wherein the knob comprises a resisting block, and the releasing block comprises a resisting groove engaging with the resisting block.

7. The chain saw according to claim 1 , wherein the driving member comprises at least one spiral guiding rail, or, the driving member is configured to a one-way cam or a two-way cam, and wherein the guiding plate comprises a guiding rail groove and a positioning plate, the positioning plate comprises protrusions matched with the driving member.

8. The chain saw according to claim 1 , wherein the transmission assembly comprises a bracket, and the bracket is fixed to the driving member by a plurality of fasteners.

Assignees

• Globe Jiangsu Co Ltd

Inventors

• Li Xiazi

Classifications

• B27B17/02

  Chain saws equipped with guide bar (B27B17/06 takes precedence) · CPC title

• B27B17/14 Primary

  Arrangements for stretching the chain saw · CPC title

• B27B17/142 Primary

  with adjustment by at least one cam · CPC title