Valve-actuating device for varying the valve lift

Patent metadata

Field	Value
Publication number	US-10830159-B2
Application number	US-201414911659-A
Country	US
Kind code	B2
Filing date	Aug 12, 2014
Priority date	Aug 12, 2013
Publication date	Nov 10, 2020
Grant date	Nov 10, 2020

Abstract

The invention relates to a valve-actuating device ( 1 ) for actuating at least one first valve of a reciprocating piston machine, in particular an internal combustion engine, which valve-actuating device can be used in particular for engine braking and comprises a first rocker arm part ( 2 ), a second rocker arm part ( 3 ), and a first switching element ( 6 ) for changing the valve stroke (H) of the at least one first valve ( 5 ), wherein the first rocker arm part ( 2 ) and the second rocker arm part ( 3 ) are pivotably supported and are arranged in such a way that at least one first valve control motion of a first camshaft ( 4 ) can be transmitted to the at least one first valve ( 5 ) by means of the first rocker arm part ( 2 ) and the second rocker arm part ( 3 ).

First claim

What is claimed is:

1. A valve control method during different operating modes for selectively providing valve actuation using motion able to be transmitted from at least one camshaft to at least one first valve by means of a valve-actuating device, wherein the valve-actuating device comprises a first rocker arm component and a second rocker arm component, which are pivotably mounted independent of one another, and a first switching element positioned between the first rocker arm component and the second rocker arm component, the method comprising the following steps:
the first rocker arm component sliding or rolling over the at least one camshaft and the at least one camshaft induces a first motion on the first rocker arm component;
providing a control pulse by means of a control fluid or electrical lines;
selectively feeding the control pulse to the first switching element to selectively set a switching position of the first switching element to control a valve lift for the at least one first valve, wherein the switching position of the first switching element depends on a magnitude and/or a length of the control pulse such that the magnitude and/or the length of the control pulse produces a sustained switching position of the switching element, and wherein the magnitude and/or the length of the control pulse can be continuously varied to provide for continuous switching positions of the first switching element in order to provide for variable valve lift for the at least one first valve; and
transmitting the first motion to the at least one first valve via the second rocker arm component depending on the sustained switching position of the first switching element.

2. The method according to claim 1 , comprising the following further step:
closing a first check valve arrangement of the first switching element.

3. The method according to claim 1 , wherein the valve-actuating device comprises a second switching element and the method comprises the following further step:
feeding the control pulse to the second switching element, wherein a switching position of the second switching element depends on the magnitude and/or the length of the control pulse.

4. The method according to claim 3 , wherein the control pulse is fed to the second switching element prior to the first switching element.

5. The method according to claim 3 , wherein the control pulse is fed to the second switching element and the first switching element simultaneously.

6. The method according to claim 3 , wherein the valve-actuating device further comprises a valve bridge connecting at least two first valves, wherein a first stop of the second rocker arm component is arranged above one of the two first valves and/or a second stop of a fourth rocker arm component is substantially arranged centrically on the valve bridge, the method comprising the following further step:
pushing the second rocker arm component off from the valve bridge by means of the second switching element above the first stop such that the second stop is distanced from the valve bridge.

7. The method according to claim 1 , wherein the valve-actuating device comprises at least two first valves and the method comprises the following further steps in a first operating mode:
opening one of the first valves; and thereafter
opening both first valves.

8. The method according to claim 1 , wherein the valve-actuating device comprises at least two first valves and the method comprises the following further step in a second operating mode:
simultaneously actuating both first valves.

9. The method according to claim 1 , wherein the valve-actuating device further comprises a third rocker arm component, a fourth rocker arm component, and a third switching element, the method comprising the following steps:
the third rocker arm component sliding or rolling over the at least one camshaft and the at least one camshaft induces a second motion on the third rocker arm component;
selectively feeding the control pulse to the third switching element to control the valve lift, wherein a position of the third switching element depends on the magnitude and/or the length of the control pulse; and
transmitting the second motion to the at least one first valve via the fourth rocker arm component depending on the position of the third switching element.

10. The method according to claim 9 , wherein the valve-actuating device further comprises a fifth rocker arm component, a sixth rocker arm component, and a fourth switching element, the method comprising the further following steps:
the fifth rocker arm component sliding or rolling over the at least one camshaft and the at least one camshaft induces a third motion on the fifth rocker arm component;
selectively feeding the control pulse to the fourth switching element to control the valve lift, wherein a position of the fourth switching element depends on the magnitude and/or the length of the control pulse; and
transmitting the third motion to a second valve via the sixth rocker arm component depending on the position of the fourth switching element.

11. The method according to claim 10 , wherein the control pulse is fed exclusively to the first switching element, the second switching element, and/or the fourth switching element in an engine braking mode of engine operation.

12. The method according to claim 10 , wherein the control pulse is fed exclusively to the third switching element and/or the fourth switching element in a drive mode or a cylinder cut-off mode of engine operation.

13. The method according to claim 10 , wherein the control pulse is fed exclusively to the second switching element, the third switching element, and/or the fourth switching element in an exhaust gas recirculation mode of engine operation.

14. The method according to claim 10 , wherein the valve-actuating device further comprises a seventh rocker arm component, an eighth rocker arm component, and a fifth switching element, the method comprising the further following steps:
the seventh rocker arm component sliding or rolling over the at least one camshaft and the at least one camshaft induces a fourth motion on the seventh rocker arm component;
selectively feeding the control pulse to the fifth switching element to control the valve lift, wherein a position of the fifth switching element depends on the magnitude and/or the length of the control pulse; and
transmitting the fourth motion to the second valve via the eighth rocker arm component depending on the position of the fifth switching element.

15. The method according to claim 14 , wherein the control pulse is fed exclusively to the third switching element and/or the fifth switching element in a Miller cycle operating mode.

16. A computer program comprising commands which when executed by a control device realizes the method in accordance with claim 1 .

17. A machine-readable medium on which the computer program in accordance with claim 16 is stored.

18. The method according to claim 1 , wherein the magnitude and/or the length of the control pulse is variable, and wherein the magnitude of the control pulse corresponds to a predetermined pressure of the control fluid and the length of the control pulse corresponds to a duration of the predetermined pressure of the control fluid.

19. The method according to claim 18 , wherein the control pulse is fed to the first switching element in a braking operating mode.

20. A valve control method during different operating modes for selectively providing valve actuation

Assignees

• Avl List Gmbh

Inventors

• Toth Gyula
• Groeger Michael

Classifications

• F02D21/08

  the other gas being the exhaust gas of engine · CPC title

• F01L13/065

  Compression release engine retarders of the "Jacobs Manufacturing" type · CPC title

• F02D13/04 Primary

  using engine as brake · CPC title

• F01L2001/467

  Lost motion springs · CPC title

• F01L1/18

  Rocking arms or levers · CPC title