Internal combustion engine having a starter device

Patent metadata

Field	Value
Publication number	US-9664143-B2
Application number	US-201414299791-A
Country	US
Kind code	B2
Filing date	Jun 9, 2014
Priority date	Jun 8, 2013
Publication date	May 30, 2017
Grant date	May 30, 2017

Abstract

An internal combustion engine has a supply channel for supplying combustion air. A throttle element is arranged in the supply channel. The engine has a starter device which enables a defined free flow cross section in the supply channel in a starting position. The starter device latches in the starting position and the latching is released by actuating an operator-controlled element. A first ramp controls the free flow cross section of the fuel port depending on the position of the throttle element. The free flow cross section of the fuel opening is controlled by a second ramp. The free flow cross section of the fuel opening, which is set using the second ramp, is greater than a flow cross section set using the first ramp for the same position of the throttle element. A favorable performance of the engine after starting thereof is achieved.

First claim

What is claimed is:

1. An internal combustion engine comprising:
an operator-controlled element;
a supply channel for supplying combustion air for the engine;
a throttle element mounted in said supply channel;
said operator-controlled element being operatively connected to said throttle element to adjust the position thereof;
a starter device having an operating position and a starting position;
a fuel port having a free flow cross section and opening into said supply channel;
a first ramp configured to control said free flow cross section of said fuel port in dependence upon the position of said throttle element when said starter device is in said operating position;
said starter device being configured to enable a defined clear flow cross section in said supply channel in said starting position;
said starter device including an actuation unit for setting said starter device in said starting position thereof;
a latching unit for latching said starter device in said starting position;
said operator-controlled element being operatively connected to said latching unit for unlatching said latching unit in response to a first actuation of said operator-controlled element after starting the internal combustion engine;
a second ramp;
said free flow cross section of said fuel port based on said second ramp being greater than a flow cross section adjusted for the same position of said throttle element based on said first ramp;
said latching unit being configured to be unlatched in response to said first actuation of said operator-controlled element;
said second ramp being configured to control said free flow cross section of said fuel port in response to said first actuation of said operator-controlled element after said unlatching of said latching unit at least up to a closing operation of said throttle element following said first actuation of said operator-controlled element;
said first actuation of said operator-controlled element effecting an opening of said throttle element; and,
said second ramp being configured to control said free flow cross section while opening said throttle element with said first actuation of said operator-controlled element.

2. The internal combustion engine of claim 1 , further comprising a guide element configured to coact with said second ramp in response to said first actuation of said operator-controlled element after said unlatching of said latching unit; and, said guide element being further configured to move out of said second ramp in response to said closing operation following said first actuation of said operator-controlled element.

3. The internal combustion engine of claim 2 , wherein said actuation unit is configured to move at most partially in the direction of said operating position in response to an unlatching of said latching unit.

4. The internal combustion engine of claim 2 , wherein said actuation unit defines an actuation axis and is configured to be rotatable about and displaceable along said actuation axis out from said operating position into said starting position.

5. The internal combustion engine of claim 2 , further comprising an additional ramp; said guide element being configured to move out of said second ramp into said additional ramp in response to said closing operation following said first actuation of said operator-controlled element; and, the free flow cross section of said fuel port adjusted based on said additional ramp being greater than a free flow cross section for the same position of said throttle element based on said first ramp and less than a flow cross section adjusted for the same position of said throttle element based on said second ramp.

6. The internal combustion engine of claim 1 , wherein said starter device is configured to hold said throttle element in a partially open position in said starting position.

7. The internal combustion engine of claim 1 , further comprising an adjustment needle projecting into said fuel port for controlling a fuel quantity fed into said supply channel; and, said starter device being configured to act on the position of said adjustment needle and, in said starting position, increase said free flow cross section of said fuel port.

8. The internal combustion engine of claim 7 , wherein said throttle element comprises a control drum rotatably journaled about a pivot axis; said adjustment needle is held on said control drum; and, said actuation unit of said starter device is configured to move said control drum in the longitudinal direction of said pivot axis.

9. The internal combustion engine of claim 1 , wherein said supply channel comprises a first supply duct for supplying combustion air and a second supply duct for supplying combustion air and fuel.

10. The internal combustion engine of claim 9 , wherein said throttle element is configured to control said first supply duct and said second supply duct.

11. The internal combustion engine of claim 10 , wherein said throttle element is a first throttle element controlling said second supply duct; and, wherein said engine includes an additional throttle element mounted in said first supply duct.

12. The internal combustion engine of claim 1 , wherein said supply channel has a free flow cross section; and, said starter device is configured to not change said free flow cross section of said supply channel in said operating position.

13. An internal combustion engine comprising:
an operator-controlled element;
a supply channel for supplying combustion air for the engine;
a throttle element mounted in said supply channel;
said operator-controlled element being operatively connected to said throttle element to adjust the position thereof;
a starter device having an operating position and a starting position;
said starter device being configured to enable a defined clear flow cross section in said supply channel in said starting position;
said starter device including an actuation unit for setting said starter device in said starting position thereof;
a latching unit for latching said starter device in said starting position;
said operator-controlled element being operatively connected to said latching unit for unlatching said latching unit in response to an actuation of said operator-controlled element;
a fuel port having a free flow cross section and opening into said supply channel;
a first ramp configured to control said free flow cross section of said fuel port in dependence upon the position of said throttle element when said starter device is in said operating position;
a second ramp configured to control said free flow cross section of said fuel port in response to a first actuation of said operator-controlled element after said unlatching of said latching unit at least up to a closing operation of said throttle element following said first actuation of said operator-controlled element;
said free flow cross section of said fuel port based on said second ramp being greater than a flow cross section adjusted for the same position of said throttle element based on said first ramp;
an intermediate stop configured to prevent a full opening of said throttle element in response to a first actuation of said operator-controlled element after said latching unit is unlatched; and,
said intermediate stop being further configured to be deactivated in response to a follow-on closing movement of said throttle element so as to permit said throttle element to be fully opened.

14. The internal combustion engine of claim 13 , wherein said intermediate stop is configured on said second ramp.

15. The internal combustion engine of claim 13 , where

Assignees

• Stihl Ag & Co Kg Andreas

Inventors

• Osburg Gerhard
• Galagas Dimitrios
• Schmidt Peter

Classifications

• F02B63/02

  for hand-held tools · CPC title

• F02M1/02 Primary

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

• F02M9/085

  Fuel spray nozzles in the throttling valves · CPC title

• F02M9/06

  with means for varying cross-sectional area of fuel spray nozzle dependent on throttle position (installations, operated automatically by a pneumatically adjustable piston-like element, for influencing fuel/air ratio F02M7/17) · CPC title

• F02D41/062

  for starting (F02D41/061 takes precedence) · CPC title