Starting device for an internal combustion engine

Patent metadata

Field	Value
Publication number	US-9303611-B2
Application number	US-201113307840-A
Country	US
Kind code	B2
Filing date	Nov 30, 2011
Priority date	Nov 30, 2010
Publication date	Apr 5, 2016
Grant date	Apr 5, 2016

Abstract

A starting device for an internal combustion engine includes a pulley mounted rotatably in a housing which can be set in rotation by a tension means to produce a drive torque for a motor shaft by a starter handle and which is connected to an engaging member by a damping spring. The drive torque is transmitted to the motor shaft to start the internal combustion engine, whereby under torsion of the damping spring, a twisting of the pulley against the engaging member is rendered possible until a stop element impacts against a counter-stop to delimit the twisting, which enables a high operational readiness of the starting device. In the case of a defect of the damping spring, the stop element and/or the counter-stop is formed from a material which has a higher strength than the material of the engaging member and/or the material of the pulley.

First claim

The invention claimed is:

1. A starting device for an internal combustion engine comprising:
a pulley mounted rotatably in a housing;
a tensioning member configured to rotate the pulley in response to a force introduced via a starter handle, the pulley being configured to produce a drive torque for a motor shaft;
an engaging member coupled with the pulley by a damping spring formed from a spring wire, the damping spring being configured to transmit the drive torque to the motor shaft to start the internal combustion engine;
a stop element arranged on the engaging member; and
a counter-stop arranged on the pulley, wherein
under torsion of the damping spring, the pulley is rotatable relative to the engaging member until the stop element impacts against the counter-stop,
the stop element and/or the counter-stop is formed from a material which has a higher strength than a material of the engaging member and/or a material of the pulley, and
the stop element is made of a metal material, and the engaging member and/or the pulley is formed from a plastic material,
the counter-stop is configured as an insert element made of a high-strength material, and is inserted in the pulley, and
the counter-stop is statically coupled relative to the pulley.

2. The starting device according to claim 1 , wherein the stop element is disposed on the engaging member and projects from a surface of the engaging member facing the pulley, wherein the stop element is configured as a pin or bolt and extends from the surface of the engaging member facing the pulley in a direction of the pulley.

3. The starting device according to claim 1 , wherein the pulley includes a guide groove in which the stop element is guided, and
the counter-stop engages the stop element in the guide groove.

4. The starting device according to claim 1 , wherein
the spring wire of the damping spring has two ends,
a first end of the spring wire is in engagement with the engaging member, and a second end of the spring wire is in engagement with the pulley, and
the counter-stop is formed from the spring wire of the damping spring, which comprises a high-hardness metal material.

5. The starting device according to claim 4 , wherein the counter-stop is formed from the second end of the spring wire of the damping spring that is in engagement with the pulley.

6. The starting device according to claim 4 , wherein the second end of the spring wire of the damping spring has a curved shape, wherein a first segment of the curved shape is encased in a receptacle of the pulley for engagement therein, and a second segment of the curved shape projects from the receptacle of the pulley in a direction of the engaging member.

7. The starting device according to claim 6 , wherein the curved shape of the second end of the spring wire of the damping spring has a S shape, or a C shape, or an inverted U shape.

8. The starting device according to claim 6 , wherein the second end of the spring wire of the damping spring extends with the curved shape in one plane, wherein the damping spring has a central axis which lies in the one plane of the second end.

9. The starting device according to claim 1 , wherein the counter-stop is made of a metal material, and the engaging member and the pulley are formed from a plastic material.

10. The starting device according to claim 1 , wherein the engaging member is formed from a plastic material.

Assignees

• Wenckel Mathias
• Ziegs Carsten
• Makita Corp

Inventors

• Wenckel Mathias
• Ziegs Carsten

Classifications

• F02N5/02 Primary

  of spring type · CPC title

• F02N15/063

  with resilient shock absorbers · CPC title

• F02N3/02

  having pull-cords · CPC title

• F02N15/065

  with blocking means · CPC title