Sliding cam system

Patent metadata

Field	Value
Publication number	US-10738665-B2
Application number	US-201816116427-A
Country	US
Kind code	B2
Filing date	Aug 29, 2018
Priority date	Sep 1, 2017
Publication date	Aug 11, 2020
Grant date	Aug 11, 2020

Abstract

The present disclosure relates to a sliding cam system for an internal combustion engine. The sliding cam system has a camshaft and a plurality of cam carriers with in each case at least two cams, the plurality of cam carriers being arranged fixedly on the camshaft so as to rotate with it and in an axially displaceable manner. The sliding cam system has a plurality of fluid-actuated actuator apparatuses which are configured in each case for axially displacing a cam carrier of the plurality of cam carriers. The sliding cam system has a fluid feed apparatus which is provided for feeding a fluid in a fluidic connection upstream of the plurality of actuator apparatuses for actuating the plurality of actuator apparatuses. At least two actuator apparatuses of the plurality of actuator apparatuses are coupled fluidically for simultaneous actuation.

First claim

We claim:

1. A sliding cam system for an internal combustion engine, the sliding cam system comprising:
a camshaft;
a plurality of cam carriers each including at least two integrally-formed cams, the plurality of cam carriers being arranged on the camshaft rotationally fixed so as to rotate with the camshaft and in an axially displaceable manner;
a plurality of fluid-actuated actuator apparatuses configured to axially displace a respective cam carrier of the plurality of cam carriers, wherein each actuator apparatus of the plurality of fluid-actuated actuator apparatuses includes a control fluid space and a retractable and extendable element partially disposed in the control fluid space, and wherein a fluid selectively fed to the control fluid space acts on the retractable and extendable element causing the retractable and extendable element to extend into an engagement track of the respective cam carrier so as to axially displace the respective cam carrier; and
a fluid feed apparatus for feeding the fluid in a fluidic connection upstream of the plurality of fluid-actuated actuator apparatuses so as to actuate the plurality of fluid-actuated actuator apparatuses,
wherein at least two actuator apparatuses of the plurality of fluid-actuated actuator apparatuses are coupled fluidically so as to actuate simultaneously.

2. The sliding cam system according to claim 1 , wherein the at least two actuator apparatuses are coupled fluidically by means of a group control valve of the fluid feed apparatus, and wherein the fluid is fed to the at least two actuator apparatuses simultaneously by opening the group control valve.

3. The sliding cam system according to claim 1 , further comprising a plurality of actuator apparatus groups, each of the plurality of actuator apparatus groups including at least two fluidically coupled actuator apparatuses of the plurality of fluid-actuated actuator apparatuses.

4. The sliding cam system according to claim 3 , wherein each actuator apparatus group is downstream of a respective group control valve of the fluid feed apparatus, and
wherein within each actuator apparatus group the fluid is fed by the fluid feed apparatus to the at least two actuator apparatuses simultaneously by of opening the respective group control valve.

5. The sliding cam system according to claim 4 , wherein the respective group control valves of each actuator apparatus group are arranged in parallel to one another.

6. The sliding cam system according to claim 1 , further comprising:
a first actuator of a first actuator apparatus of the plurality of fluid-actuated actuator apparatuses coupled fluidically to a first actuator of a second actuator apparatus of the plurality of fluid-actuated actuator apparatuses; or
a second actuator of the first actuator apparatus being coupled fluidically to a second actuator of the second actuator apparatus.

7. The sliding cam system according to claim 1 , wherein each fluid-actuated actuator apparatus includes a first actuator for displacing a respective cam carrier in a first direction, and a second actuator for displacing the respective cam carrier in a second direction which is opposite the first direction.

8. The sliding cam system according to claim 1 , wherein the plurality of fluid-actuated actuator apparatuses is actuated hydraulically or pneumatically.

9. The sliding cam system according to claim 1 , further comprising:
a position sensor which detects a rotational position of the camshaft, an internal combustion engine sensor which detects an operating parameter of the internal combustion engine, or a user interface for a user input; and
a control unit configured to control the fluid feed apparatus based on the detected rotational position, the detected operating parameter, or the user input.

10. The sliding cam system according to claim 9 , wherein the control unit is further configured to selectively actuate a response group control valve of the fluid feed apparatus based on the detected rotational position, the detected operating parameter, or the user input.

11. The sliding cam system according to claim 1 , wherein the retractable and extendable element is a pin.

12. The sliding cam system according to claim 1 , wherein the fluid is a compressible gas, and the control fluid space is filled with the compressible gas such that the compressible gas acts as a pneumatic spring during retraction of the retractable and extendable element.

13. The sliding cam system according to claim 12 , wherein the compressible gas is air.

14. The sliding cam system according to claim 1 ,
wherein the fluid is fed to the control fluid space in such a way that the retractable and extendable element makes contact with an outer circumferential face of the respective cam carrier before the retractable and extendable element engages the engagement track.

15. The sliding cam system according to claim 1 , wherein the retractable and extendable element is prestressed by an elastic element into a retracted state.

16. The sliding cam system according to claim 1 , wherein the control fluid space is configured as an annular space in a retracted state of the retractable and extendable element.

17. The sliding cam system according to claim 1 , wherein each actuator apparatus further includes a fluid seal configured to seal the control fluid space from a surrounding area of the actuator apparatus.

18. A motor vehicle, comprising:
a sliding cam system for an internal combustion engine, the sliding cam system including:
a camshaft;
a plurality of cam carriers each including at least two integrally-formed cams, the plurality of cam carriers being arranged on the camshaft rotationally fixed so as to rotate with the camshaft and in an axially displaceable manner;
a plurality of fluid-actuated actuator apparatuses configured to axially displace a respective cam carrier of the plurality of cam carriers, wherein each actuator apparatus of the plurality of fluid-actuated actuator apparatuses includes a control fluid space and a retractable and extendable element partially disposed in the control fluid space, and wherein a fluid selectively fed to the control fluid space acts on the retractable and extendable element causing the retractable and extendable element to extend into an engagement track of the respective cam carrier so as to axially displace the respective cam carrier; and
a fluid feed apparatus for feeding the fluid in a fluidic connection upstream of the plurality of fluid-actuated actuator apparatuses so as to actuate the plurality of fluid-actuated actuator apparatuses,

wherein at least two actuator apparatuses of the plurality of fluid-actuated actuator apparatuses are coupled fluidically so as to actuate simultaneously.

19. The motor vehicle of claim 18 , wherein the fluid feed apparatus is a compressed air tank of the motor vehicle.

20. The motor vehicle of claim 18 , wherein the motor vehicle is a commercial vehicle.

Assignees

• Man Truck & Bus Ag

Inventors

• Dietrich Jens
• Malischewski Thomas
• Hirschmann Steffen

Classifications

• F01L13/0036 Primary

  the valves being driven by two or more cams with different shape, size or timing or a single cam profiled in axial and radial direction · CPC title

• F01L2001/34426

  Oil control valves · CPC title

• F01L2305/00

  Valve arrangements comprising rollers · CPC title

• F01L2820/034

  Pneumatic engines · CPC title

• F01L2013/0052

  with cams provided on an axially slidable sleeve · CPC title