Hand-guided power tool with an internal combustion engine

Patent metadata

Field	Value
Publication number	US-10215131-B2
Application number	US-201715728856-A
Country	US
Kind code	B2
Filing date	Oct 10, 2017
Priority date	Oct 31, 2016
Publication date	Feb 26, 2019
Grant date	Feb 26, 2019

Abstract

A power tool has an internal combustion engine with a carburetor with choke element pivotably arranged therein. A starter device with an actuating element has an operating position, off position, and at least one start position. A coupling element connects the actuating element with a choke actuating lever. The actuating element, upon adjustment from operating position into the at least one start position, moves the choke element into its start position. The connection between actuating element and choke actuating lever has a relative movement device which, in one position of the choke element, enables movement of actuating element relative to choke actuating lever. A holding device with guide contour is secured on the carburetor housing. In a start position of the choke element, the guide contour prevents movement of the actuating element relative to choke actuating lever from its start position into the operating position.

First claim

What is claimed is:

1. A hand-guided power tool comprising:
an internal combustion engine comprising a carburetor, the carburetor comprising a carburetor housing in which an intake passage section is formed, wherein the carburetor further comprises a pivotably supported choke element arranged in the intake passage section and operatively connected with a choke actuating lever;
a starter device comprising an operating position, an off position, and at least one start position;
the starter device comprising an actuating element configured to be actuated by an operator;
the starter device further comprising a coupling element connecting by an operative connection the actuating element with the choke actuating lever, wherein the actuating element, when adjusting the starter device from the operating position into the at least one start position, moves the choke element into at least one start position of the choke element correlated with the at least one start position of the starter device;
the operative connection between the actuating element and the choke actuating lever comprising a relative movement device which, in at least one position of the choke element, enables a relative movement of the actuating element relative to the choke actuating lever;
wherein the relative movement device comprises a holding device comprising a guide contour stationarily secured on the carburetor housing;
wherein the guide contour, in the at least one start position of the choke element, holds the actuating element in the at least one start position of the starter device and prevents the actuating element from moving relative to the choke actuating lever from the at least one start position of the starter device into the operating position of the starter device.

2. The power tool according to claim 1 , wherein the operative connection comprises a guide element and the relative movement device comprises a slotted hole, wherein the guide element engages the slotted hole, wherein the guide element is moved from a first position into a second position in the slotted hole when the actuating element is moved from the operating position of the starter device into the off position of the starter device.

3. The power tool according to claim 2 , wherein the guide element is moved from the first position into at least one third position when the actuating element is moved from the operating position of the starter device into the at least one start position of the starter device.

4. The power tool according to claim 2 , wherein the slotted hole comprises a first section, a second section, and a connecting section connecting the first section and the second section with each other, wherein the first section and the second section are positioned at an angle of more than 45° relative to each other, and wherein the guide element in the second position is located in the first section.

5. The power tool according to claim 4 , wherein the guide element is moved from the first position into at least one third position when the actuating element is moved from the operating position of the starter device into the at least one start position of the starter device, wherein the guide element in the at least one third position is located in the second section.

6. The power tool according to claim 4 , wherein the guide element in the first position is located in the connecting section.

7. The power tool according to claim 2 , wherein the guide contour closes off at least one section of the slotted hole for the guide element when the actuating element is in the at least one start position of the starter device.

8. The power tool according to claim 7 , wherein the guide contour is provided on a control opening into which the guide element projects.

9. The power tool according to claim 8 , wherein the control opening in an operating position of the choke element completely overlaps the slotted hole in a movement range of the coupling element.

10. The power tool according to claim 8 , wherein the guide contour is formed on a component fixedly connected with a carburetor housing of the carburetor.

11. The power tool according to claim 2 , wherein the guide element is embodied on the coupling element and the slotted hole is provided on the choke actuating lever.

12. The power tool according to claim 11 , wherein the coupling element is embodied as a wire bracket and the guide element is an angled end of the wire bracket.

13. The power tool according to claim 1 , wherein the choke actuating lever is connected fixedly with the choke element.

14. The power tool according to claim 1 , wherein the relative movement device enables the actuating element to move relative to the choke actuating lever from the operating position of the starter device into the off position of the starter device.

15. The power tool according to claim 1 , wherein the relative movement device enables the actuating element to move relative to the choke actuating lever from the operating position of the starter device into the at least one start position of the starter device.

Assignees

• Stihl Ag & Co Kg Andreas

Inventors

• Schulz Andreas
• Zurek Przemyslaw
• Bernhard Tobias

Classifications

• F02M1/02 Primary

  the means to facilitate starting or idling being chokes for enriching fuel-air mixture (automatic chokes F02M1/08) · CPC title

• F02B63/02

  for hand-held tools · CPC title

• F02M19/00

  Details, component parts, or accessories of carburettors, not provided for in, or of interest apart from, the apparatus of groups F02M1/00 - F02M17/00 · CPC title

• F02N3/02

  having pull-cords · CPC title

• F02D2009/0254

  Mechanical control linkage between accelerator lever and throttle valve · CPC title