Internal combustion engine

Patent metadata

Field	Value
Publication number	US-9976494-B2
Application number	US-201615075533-A
Country	US
Kind code	B2
Filing date	Mar 21, 2016
Priority date	Mar 27, 2015
Publication date	May 22, 2018
Grant date	May 22, 2018

Abstract

An internal combustion engine with an adjustable compression ratio has connecting rods ( 1 ), each of which has a hydraulically adjustable eccentric adjustment device arranged in a connecting rod bearing eye ( 2 ) and/or in a crankpin bearing eye ( 3 ) for adjusting an effective connecting rod length (l eff ) of the respective connecting rod ( 1 ). Travel of the eccentric adjustment device is controlled by a switchover valve ( 10 ). Each switchover valve ( 10 ) has a pick-off means ( 14 ). The switchover valves ( 10 ) can be actuated by an actuation device ( 15 ) that has a switching fork ( 16 ) for each switchover valve ( 10 ) and thus for each pick-off means ( 14 ) to be actuated. The pick-off means ( 14 ) and the switching forks ( 16 ) are oriented relative to one another so that inertial forces acting during driving assist the actuation of the switchover valves ( 10 ) by the actuation device ( 15 ).

First claim

What is claimed is:

1. An internal combustion engine for a motor vehicle, the internal combustion engine having an adjustable compression ratio and comprising multiple connecting rods, each of the connecting rods having a hydraulically adjustable eccentric adjustment device arranged in a connecting rod bearing eye and/or in a crankpin bearing eye for adjusting an effective connecting rod length (l eff ) of the respective connecting rod, each of the eccentric adjustment devices having a switchover valve for controlling an adjustment travel of the eccentric adjustment device, each of the switchover valves having an actuatable element, an actuating device configured for actuating the switchover valves, the actuating device having a switching fork for each of the switchover valves and for each of the actuatable elements to be actuated, the actuatable elements of the switchover valves and the switching forks of the actuating device are oriented relative to one another such that inertial forces acting during driving of the motor vehicle assist the actuation of the switchover valves by the actuating device.

2. The internal combustion engine of claim 1 , wherein, when the switchover valves assume a switching position for part-load operation of the internal combustion engine, the actuatable elements of the switchover valves are oriented so that inertial forces acting during an acceleration of the motor vehicle cause a relative movement between the switching forks of the actuating device and the actuatable elements of the switchover valves that assists a transfer of the switchover valves into a switching position for full-load operation of the internal combustion engine.

3. The internal combustion engine of claim 2 , wherein, when the switchover valves assume the switching position for part-load operation of the internal combustion engine, the actuatable elements of the switchover valves protrude forward in a forward direction of travel of the motor vehicle, in relation to a connecting rod main body.

4. The internal combustion engine of claim 3 , wherein inertial forces that act during acceleration of the motor vehicle cause a front switching fork section of the switching forks to abut against a section that protrudes forward in relation to a connecting rod main body of the actuatable elements of the switchover valves.

5. The internal combustion engine of claim 1 , wherein when the switchover valves assume a switching position for full-load operation of the internal combustion engine, the actuatable elements of the switchover valves are oriented so that inertial forces that act during deceleration of the motor vehicle cause a relative movement between the switching forks of the actuating device and the actuatable elements of the switchover valves to assist a transfer of the switchover valves into a switching position for part-load operation of the internal combustion engine.

6. The internal combustion engine of claim 5 , wherein, when the switchover valves assume the switching position for full-load operation of the internal combustion engine, the actuatable elements of the switchover valves protrude rearward, as viewed in a forward direction of travel, in relation to a connecting rod main body.

7. The internal combustion engine of claim 6 , wherein inertial forces that act during a deceleration of the motor vehicle cause a rear switching fork section of the switching forks to abut against a section that protrudes rearward in relation to a connecting rod main body of the actuatable elements of the switchover valves.

Assignees

• Porsche Ag
• Porsche Ag

Inventors

• Paul Michael
• Klampfl Marco
• Ickinger Frank

Classifications

• F16C7/06

  Adjustable connecting-rods · CPC title

• F02D15/02 Primary

  by alteration or displacement of piston stroke · CPC title

• F02B75/243

  with only one crankshaft of the "boxer" type, e.g. all connecting rods attached to separate crankshaft bearings · CPC title

• F02B75/045 Primary

  by means of a variable connecting rod length · CPC title