Handheld work apparatus

Patent metadata

Field	Value
Publication number	US-9855672-B2
Application number	US-201514875158-A
Country	US
Kind code	B2
Filing date	Oct 5, 2015
Priority date	Oct 15, 2014
Publication date	Jan 2, 2018
Grant date	Jan 2, 2018

Abstract

A handheld work apparatus has a drive motor which drives a tool of the work apparatus. A lubricating arrangement is provided for the tool. The lubricating arrangement includes a lubricant piece that is solid at 20° C. The work apparatus has a melting chamber into which the lubricant piece projects and which is connected to the tool via at least one lubricant channel. The melting chamber is delimited at least partially by a heat conducting element which is heated during operation of the work apparatus.

First claim

What is claimed is:

1. A handheld work apparatus comprising:
a worktool;
a drive motor configured to drive said worktool;
a lubricating arrangement for said worktool;
said lubricating arrangement including a lubricant piece configured to be solid at 20° C.;
said lubricating arrangement including a melting chamber;
said lubricant piece having a projection projecting into said melting chamber;
said lubricating arrangement including a lubricant channel connecting said melting chamber to said worktool;
said lubricating arrangement including a heat conducting element configured to be heated during operation of the handheld work apparatus; and,
said melting chamber being at least partially delimited by said heat conducting element such that said projection of said lubricant piece can be heated and melted in said melting chamber and be guided to said worktool through said lubricant channel.

2. The handheld work apparatus of claim 1 , wherein said worktool is connected to said heat conducting element to heat said heat conducting element during operation of the handheld work apparatus.

3. The handheld work apparatus of claim 1 , wherein said lubricating arrangement includes a pre-tensioning device configured to push said lubricant piece in a direction toward said melting chamber.

4. The handheld work apparatus of claim 1 , wherein:
said lubricant piece has an outer contour;
said melting chamber defines an opening and,
said opening having an opening contour adapted to said outer contour of said lubricant piece.

5. The handheld work apparatus of claim 4 further comprising a sealing arrangement arranged at said opening.

6. The handheld work apparatus of claim 1 further comprising:
a housing;
said work tool being arranged on said housing;
said drive motor being arranged in said housing;
said melting chamber of said lubricating arrangement being arranged in said housing; and,
said lubricating arrangement including a holder releasably held on said housing so as to be removable therefrom and configured for accommodating said lubricant piece.

7. The handheld work apparatus of claim 6 , wherein:
said housing includes a receptacle;
said holder includes a tubular base body; and,
said tubular base body is arranged in said receptacle when said holder is held on said housing.

8. The handheld work apparatus of claim 7 , wherein said receptacle includes an opening to the ambient, said opening being arranged at a portion of a circumference of said tubular base body.

9. The handheld work apparatus of claim 6 , wherein:
said lubricant piece has an end facing away from said melting chamber;
said lubricating arrangement includes a pressure piece configured to contact said lubricant piece at said end thereof facing away from said melting chamber; and,
said lubricating arrangement includes biasing means for pretensioning said pressure piece toward said melting chamber.

10. The handheld work apparatus of claim 9 , wherein said holder includes at least one end stop for said pressure piece.

11. The handheld work apparatus of claim 1 , wherein the handheld work apparatus is a chain saw, the handheld work apparatus further comprising:
said heat conducting element is configured as a side plate; and,
said worktool includes a guide bar contacting said side plate and a saw chain arranged circumferentially on said guide bar.

12. The handheld work apparatus of claim 11 further comprising:
an intermediate plate contacting said side plate; and,
said lubricant channel being delimited by said intermediate plate and side plate.

13. The handheld work apparatus of claim 12 , wherein:
said side plate has a through-opening formed therein;
said intermediate plate has a recess formed therein delimiting said lubricant channel; and,
said recess extends up to said through-opening.

14. The handheld work apparatus of claim 11 , wherein:
said guide bar defines a plane; and,
said lubricant piece defines a longitudinal center axis arranged approximately perpendicular to said plane.

15. The handheld work apparatus of claim 1 further comprising a heating device configured to be operated by said drive motor and to heat said heat conducting element.

16. The handheld work apparatus of claim 1 , wherein:
said drive motor is a combustion engine having an exhaust-gas muffler; and,
said heat conducting element is heated by at least one of said exhaust-gas muffler and exhaust gas exiting said exhaust-gas muffler.

Assignees

• Stihl Ag & Co Kg Andreas

Inventors

• Zimmermann Helmut
• Karrar Carel
• Frey Benjamin

Classifications

• B27B17/12 Primary

  Lubricating devices specially designed for chain saws · CPC title

• F16N39/04

  by heating (heat-exchangers in general F28) · CPC title

• F16N11/04

  Spring-loaded devices · CPC title

• F16N21/00

  Conduits; Junctions (in general F16L); Fittings for lubrication apertures · CPC title