Dual ramp actuator controlling a two clutch system for a driveline

Patent metadata

Field	Value
Publication number	US-9976605-B2
Application number	US-201514978918-A
Country	US
Kind code	B2
Filing date	Dec 22, 2015
Priority date	Dec 22, 2015
Publication date	May 22, 2018
Grant date	May 22, 2018

Abstract

A ball ramp actuator assembly including a control ring, an activation ring including a first section and a second section, two circumferential plate grooves formed between the control ring and the sections of the activation ring which contain rolling elements, two clutches, a gear and an actuator. The first and second sections are splined together allowing for axial movement. The first clutch is connected to the first section of the activation ring and a second clutch is connected to the second section of the activation ring. The rotation of a section of the activation ring axially in one direction allows the corresponding plate groove to expand and apply a load to the corresponding clutch while the other section of the activation ring remains inactive and rotation in the opposite direction activates the other clutch respectively.

First claim

I claim:

1. A ball ramp actuator assembly comprising:
a control ring;
an activation ring, wherein the activation ring includes a first section and a second section, wherein the first and second sections are splined together allowing for axial movement;
two circumferential plate grooves, wherein the first groove is formed between the control ring and the first section of the activation ring and the second groove is formed between the control ring and the second section of the activation ring;
a plurality of rolling elements interposed between the control ring and the activation ring in the circumferential plate grooves;
a gear, wherein the gear is drivingly connected to the activation ring;
an actuator, wherein the actuator is drivingly connected to the gear;
a first clutch connected to the first section of the activation ring;
a second clutch connected to the second section of the activation ring;
wherein the first section of the activation ring is arranged to rotate axially when the gear moves in a first rotary direction, allowing the first circumferential plate grooves to expand applying a load to the first clutch and the second section of the activation ring to remain stationary;
wherein the second section of the activation ring is arranged to rotate axially when the gear moves in a second rotary direction, opposite the first rotary direction, allowing the second circumferential plate grooves to expand applying a load to the second clutch and the first section of the activation ring to remain stationary; and
wherein the pair of clutches cannot be actuated at the same time.

2. A ball ramp actuator assembly of claim 1 , wherein each circumferential plate groove comprises a first section, a second section and third section, wherein each section has a gradient and the gradients of the second and third sections differ to provide different rates of axial displacement of the activation ring, wherein the first section has a gradient different from the second and third sections which allows the rolling element to remain in the first section if there is no rotation of the activation ring, and wherein the first, second and third sections are joined together to form a single continuous groove.

3. The ball ramp actuator assembly of claim 2 , wherein each circumferential plate groove further comprises a fourth section, wherein the fourth section of the first groove allows for relative rotation of the first clutch without axial movement of the first section of the activation ring and the fourth section of the second groove allows for relative rotation of the second clutch without axial movement of the second section of the activation ring.

4. The ball ramp actuator assembly of claim 2 , wherein the gradient of the second section is steeper than the gradient of the third section or first section.

5. The ball ramp actuator assembly of claim 2 , wherein the first section of the grooves provide a neutral position for the assembly wherein the control ring and activation ring are at minimum axial distance from each other.

6. A ball ramp mechanism, comprising:
a control ring;
an activation ring, wherein the activation ring includes a first section and a second section, wherein the first and second sections are splined together allowing for axial movement;
two circumferential plate grooves, wherein a first groove is formed between the control ring and the first section of the activation ring and a second groove is formed between the control ring and the second section of the activation ring;
a plurality of rolling elements interposed between the control ring and the activation ring in the circumferential plate grooves;
wherein the first section of the activation ring is arranged to rotate axially in a first rotary direction while the second section of the activation ring remains stationary; and
wherein the second section of the activation ring is arranged to rotate axially in a second rotary direction, opposite the first rotary direction, and the first section of the activation ring remains stationary;
wherein the first section and second section of the activation ring are axially aligned.

7. The ball ramp mechanism of claim 6 , wherein each section of the activation ring has a radial inner surface and a radial outer surface, wherein a plurality of splines are formed on the radial inner surface of the first section and a plurality of splines are formed on the radial outer surface of the second section, and the splines on the first section and the splines on the second section directly engage one another.

8. The ball ramp mechanism of claim 6 , wherein each circumferential plate groove comprises a first section, a second section and third section, wherein each section has a gradient and the gradients of the second and third sections differ to provide different rates of axial displacement of the activation ring, wherein the first section has a gradient different from the second and third sections which allows the rolling element to remain in the first section if there is no rotation of the activation ring, and wherein the first, second and third sections are joined together to form a single continuous groove.

9. The ball ramp mechanism of claim 8 , wherein each circumferential plate groove further comprises a fourth section, wherein the fourth section of the first groove allows the first section of the activation ring to remain stationary and the fourth section of the second groove allows for the second section of the activation ring to remain stationary.

10. The ball ramp mechanism of claim 8 , wherein the gradient of the second section is steeper than the gradient of the third section or first section.

11. The ball ramp mechanism of claim 8 , wherein the first section of the grooves provide a neutral position for the ball ramp mechanism wherein the control ring and activation ring are at minimum axial distance from each other.

12. A method of operating a ball ramp actuator to selectively engage one clutch of a two clutch system, comprising the steps of:
providing a ball ramp actuator assembly comprising a gear, an activation ring including a first section and a second section splined together for axial movement, a control ring, two circumferential grooves, one groove formed between the control ring and each section of the activation ring, a first clutch and a second clutch;
rotating the gear in a first rotary direction causing the first section of the activation ring to rotate from a neutral position in a first direction and rolling elements located in the circumferential grooves to move along the circumferential grooves in a first direction expanding a distance between the first section of the activation ring and the control ring applying a load to the first clutch;
returning the first section of the activation ring to the neutral position to remove the load on the first clutch; and
rotating the gear in a second rotary direction, opposite the first rotary direction, causing the second section of the activation ring to rotate from a neutral position in a second rotary direction and the rolling elements to move along the circumferential grooves in a second direction, opposite the first direction, expanding a distance between the second section of the activation ring and the control ring applying a load to the second clutch.

13. The method of claim 12 , further comprising the step of further rotating the gear in the first rotary direction, prior to returning the first section of the activation ring to the neutral position, causing the rolling elements to move further along the circumferential grooves in the first direction and to continue to apply the load to the f

Assignees

• Dana Automotive Systems Group

Inventors

• Cooper Kenneth E

Classifications

• F16D21/06

  at least two driving shafts or two driven shafts being concentric · CPC title

• F16D23/12 Primary

  Mechanical clutch-actuating mechanisms arranged outside the clutch as such (specific for combined clutches F16D21/00; mechanisms specific for synchronisation F16D23/02) · CPC title

• F16D2121/14

  Mechanical · CPC title

• F16D2125/46

  Rotating members in mutual engagement · CPC title

• F16D2023/123

  Clutch actuation by cams, ramps or ball-screw mechanisms · CPC title