Actuating mechanism for a switchable rocker arm

Patent metadata

Field	Value
Publication number	US-12416251-B2
Application number	US-202418899995-A
Country	US
Kind code	B2
Filing date	Sep 27, 2024
Priority date	Apr 22, 2022
Publication date	Sep 16, 2025
Grant date	Sep 16, 2025

Abstract

An actuation mechanism for selective switching of a valvetrain switching mechanism by a linear actuator mechanism includes an actuator arm having a pin contact surface for engaging an actuator pin of a linear actuator mechanism, a switching arm, and a lever axle pivotally coupling the actuator arm and the switching arm and rotatable about a lever axis, wherein the actuation mechanism is configured to rotate about the lever axis based on a selective extension of the actuator pin, wherein the switching arm is configured to selectively act on the valvetrain switching mechanism based on the rotation of the actuation mechanism; and wherein multiple interface positions on the pin contact surface of the actuator arm are each configured to cooperatively engage with the actuator pin at an orthogonal angle to the axis of linear motion of the actuator pin.

First claim

What is claimed:

1. An actuation mechanism for selective switching of a valvetrain switching mechanism by a linear actuator mechanism, the actuation mechanism comprising:
an actuator arm comprising a first end and a second end opposite the first end, the second end of the actuator arm comprising a pin contact surface configured to cooperatively engage with a selectively and linearly extendable actuator pin of the actuator mechanism;
a switching arm comprising a first end and a second end opposite the first end; and
a lever axle pivotally coupling the actuator arm and the switching arm at the first end of each of the actuator arm and the switching arm, the lever axle rotatable about a lever axis;
wherein the actuation mechanism is configured to:
rotate about the lever axis in a first direction based on an extension of the actuator pin along an axis of linear motion of the actuator pin, and
rotate about the lever axis in a second direction opposite to the first direction based on a retraction of the actuator pin along the axis of linear motion of the actuator pin;

wherein the second end of the switching arm is configured to selectively act on a switching element of the valvetrain switching mechanism based on the rotation of the actuation mechanism; and
wherein, based on the rotation of the actuation mechanism about the lever axis, a plurality of interface positions disposed on the pin contact surface of the actuator arm are each configured to cooperatively engage with the actuator pin at an orthogonal angle to the axis of linear motion of the actuator pin.

2. The actuation mechanism of claim 1 , wherein the pin contact surface comprises a curved surface having a curvature along a contact trajectory of the pin contact surface with the actuator pin, the plurality of interface positions disposed along the contact trajectory.

3. The actuation mechanism of claim 1 , further comprising one or more second switching arms, each second switching arm comprising a first end and a second end, wherein the lever axle further pivotally couples the respective first end of each second switching arm to be rotatable about the lever axis, and wherein the respective second end of each second switching arm is configured to selectively act on a respective second switching element of the valvetrain switching mechanism based on the rotation of the actuation mechanism.

4. The actuation mechanism of claim 1 , further comprising a biasing member configured to bias rotation of the actuation mechanism in the first direction or the second direction.

5. The actuation mechanism of claim 1 , further comprising a supporting member coaxially provided with the lever axle and configured to secure the actuation mechanism to an external structure.

6. The actuation mechanism of claim 5 , further comprising an over-travel limiter coaxially provided with the lever axle and rotatably coupled with the lever axle, the over-travel limiter structured to constrain a rotational travel limit of the switching arm.

7. An actuation system for a switchable valvetrain assembly, the actuation system comprising:
a linear actuator comprising a selectively extendable actuator pin;
a rocker arm of the switchable valvetrain assembly, the rocker arm further comprising a switchable latching pin; and
an actuation mechanism comprising:
an actuator arm comprising a first end and a second end opposite the first end, the second end of the actuator arm comprising a pin contact surface configured to cooperatively engage with the actuator pin;
a switching arm comprising a first end and a second end opposite the first end; and
a lever axle pivotally coupling the actuator arm and the switching arm at the first end of each of the actuator arm and the switching arm, the lever axle rotatable about a lever axis;

wherein the actuation mechanism is configured to rotate about the lever axis between a first lever position and a second lever position based on a selective extension of the actuator pin along an axis of linear motion of the actuator pin;
wherein the second end of the switching arm is configured to selectively switch the switchable latching pin of the rocker arm based on the position of the actuation mechanism; and
wherein, based on the rotation of the actuation mechanism about the lever axis, a plurality of interface positions disposed on the pin contact surface of the actuator arm are each configured to cooperatively engage with the actuator pin at an orthogonal angle to the axis of linear motion of the actuator pin.

8. The actuation system of claim 7 , wherein the pin contact surface comprises a curved surface having a curvature along a contact trajectory of the pin contact surface with the actuator pin, the plurality of interface positions disposed along the contact trajectory.

9. The actuation system of claim 7 , further comprising one or more second switching arms, each second switching arm comprising a first end and a second end, wherein the lever axle further pivotally couples the respective first end of each second switching arm to be rotatable about the lever axis, and wherein the respective second end of each second switching arm is configured to selectively switch a respective second switchable latching pin based on the rotation of the actuation mechanism.

10. The actuation system of claim 7 , further comprising a biasing member configured to bias rotation of the actuation mechanism toward the first lever position or the second lever position.

11. The actuation system of claim 7 , further comprising a supporting member coaxially provided with the lever axle and configured to secure the actuation mechanism to an external structure.

12. The actuation system of claim 11 , further comprising an over-travel limiter coaxially provided with the lever axle and rotatably coupled with the lever axle, the over-travel limiter structured to constrain a rotational travel limit of the switching arm based on the over-travel limiter selectively contacting the supporting member to prevent rotation of the switching arm.

13. The actuation system of claim 10 , wherein an actuator arm distance and a switching arm distance are configured based on at least a force rating and a stroke length rating of the actuator pin, such that the actuator pin is enabled to selectively act on the actuation mechanism and correspondingly selectively switch the switchable latching pin of the rocker arm;
wherein the actuator arm distance is defined as a shortest distance between the axis of linear motion of the actuator pin and the lever axis, and
wherein a switching arm distance is defined as a shortest distance between a longitudinal axis of the switchable latching pin and the lever axis.

14. The actuation system of claim 13 , wherein the actuator arm distance and the switching arm distance are configured further based on one or more latching pin parameters of the switchable latching pin.

15. The actuation system of claim 14 , wherein a biasing member of the actuation mechanism is configured based on at least the actuator arm distance and the switching arm distance of the actuation mechanism.

16. A method of selectively switching a latching pin of a rocker arm by a linear actuator mechanism, the method comprising:
selectively extending an actuator pin of the actuator mechanism between a first actuator pin position and a second actuator pin position along an axis of linear motion, the actuator pin engaging a pin contact surface of an actuation mechanism, the actuation mechanism comprising an actuator arm and a switching arm, the pin contact surface provided at an end of the actuator arm

Assignees

• Eaton Intelligent Power Ltd

Inventors

• Lorenzon Alessio
• Canzoniere Egidio

Classifications

• F01L2001/186

  Split rocking arms, e.g. rocker arms having two articulated parts and means for varying the relative position of these parts or for selectively connecting the parts to move in unison · CPC title

• F01L2001/187

  Clips, e.g. for retaining rocker arm on pivot · CPC title

• F01L1/2411

  by means of a hydraulic adjusting device located between the valve stem and rocker arm · CPC title

• F01L1/185 Primary

  Overhead end-pivot rocking arms · CPC title