Variable damping system using a piezoelectric device

Patent metadata

Field	Value
Publication number	US-9777792-B2
Application number	US-201514960624-A
Country	US
Kind code	B2
Filing date	Dec 7, 2015
Priority date	Dec 7, 2015
Publication date	Oct 3, 2017
Grant date	Oct 3, 2017

Abstract

A damper assembly includes a housing and rod supported by the housing. A piston assembly is attached to the rod, and is positioned to separate an interior chamber of the housing into a first fluid chamber and a second fluid chamber. The piston assembly includes an annular plate that defines at least one orifice. The orifice interconnects the first fluid chamber and the second fluid chamber in fluid communication. The damper assembly includes a piezoelectric device that is moveable between a disengaged position and an engaged position, in response to a control signal. When disposed in the disengaged position, the piezoelectric device does not affect fluid flow through the at least one orifice. When disposed in the engaged position, the piezoelectric device does affect fluid flow through the at least one orifice, to adjust a damping rate of the piston assembly.

First claim

The invention claimed is:

1. A fluid metering device comprising:
a housing defining a first fluid chamber and a second fluid chamber;
a valve having at least one orifice for controlling fluid flow between the first fluid chamber and the second fluid chamber;
a piezoelectric device moveable between at least a first position and a second position, wherein the piezoelectric device affects fluid flow through the at least one orifice when disposed in the first position at a first rate, and wherein the piezoelectric device affects fluid flow through the at least one orifice when disposed in the second position at a second rate;
wherein the valve includes at least one valve disc;
wherein the at least one valve disk is bendable about a spring point in response to a fluid pressure to control fluid flow through the at least one orifice, between the first fluid chamber and the second fluid chamber; and
wherein the piezoelectric device engages the at least one valve disk to move the spring point, about which the at least one valve disk bends, radially outward relative to a longitudinal axis, to change the fluid pressure required to bend the at least one valve disk when the piezoelectric device is disposed in the second position.

2. The damper assembly set forth in claim 1 wherein the piezoelectric device partially blocks the at least one orifice when disposed in the second position to reduce fluid flow through the at least one orifice.

3. A damper assembly comprising:
a housing defining an interior chamber, and extending along a longitudinal axis;
a rod supported by the housing and at least partially disposed within the interior chamber of the housing;
a piston assembly attached to the rod within the interior chamber of the housing, and positioned to separate the interior chamber into at least a first fluid chamber and a second fluid chamber, and operable to resist relative movement between the rod and the housing at a damping rate;
wherein the piston assembly includes an annular plate defining at least one orifice interconnecting the first fluid chamber and the second fluid chamber in fluid communication;
a piezoelectric device moveable between at least a disengaged position and an engaged position in response to a control signal, wherein the piezoelectric device does not affect fluid flow through the at least one orifice when disposed in the disengaged position, and wherein the piezoelectric device does affect fluid flow through the at least one orifice when disposed in the engaged position to adjust the damping rate of the piston assembly;
wherein the piston assembly includes at least one valve disc disposed adjacent a face of the annular plate, between the piezoelectric device and the annular plate;
wherein the at least one valve disk is bendable relative to the rod about a spring point in response to a fluid pressure to control fluid flow through the at least one orifice, between first fluid chamber and the second fluid chamber; and
wherein the piezoelectric device engages the at least one valve disk to move the spring point, about which the at least one valve disk bends, radially outward relative to the longitudinal axis, to change the fluid pressure required to bend the at least one valve disk when the piezoelectric device is disposed in the engaged position.

4. The damper assembly set forth in claim 3 wherein the piezoelectric device is disposed within the interior chamber of the housing, and is attached to the rod adjacent the piston assembly.

5. The damper assembly set forth in claim 4 wherein the piezoelectric device moves linearly along the longitudinal axis in response to the control signal, to move between the disengaged position and engaged position.

6. The damper assembly set forth in claim 5 wherein the piezoelectric device is moveable along the longitudinal axis to at least one intermediate position disposed between the engaged position and the disengaged position.

7. The damper assembly set forth in claim 5 wherein the piezoelectric device partially blocks the at least one orifice when disposed in the engaged position to reduce fluid flow through the at least one orifice.

8. The damper assembly set forth in claim 3 wherein the at least one orifice includes a plurality of orifices, and wherein the piezoelectric device completely blocks at least one of the plurality of orifices when disposed in the engaged position.

9. A damping system comprising:
a control module operable to generate a control signal;
a damper assembly coupled to the control module, and including a piezoelectric device operable to move between an engaged position and a disengaged position in response to the control signal;
wherein the damper assembly includes a housing defining an interior chamber, and a piston assembly disposed within the interior chamber and positioned to separate the interior chamber into a first fluid chamber and a second fluid chamber;
wherein the piston assembly includes an annular plate defining at least one orifice interconnecting the first fluid chamber and the second fluid chamber in fluid communication;
a damping fluid disposed within the interior chamber of the housing, and moveable through the at least one orifice between the first fluid chamber and the second fluid chamber;
wherein the piezoelectric device does not affect fluid flow through the at least one orifice when disposed in the disengaged position,
wherein the piezoelectric device does affect fluid flow through the at least one orifice when disposed in the engaged position to control a flow of the damping fluid through the at least one orifice and adjust a damping rate of the piston assembly;
wherein the piston assembly includes at least one valve disc disposed adjacent a face of the annular plate, between the piezoelectric device and the annular plate;
wherein the at least one valve disk is bendable relative to the rod about a spring point in response to a fluid pressure applied by the damping fluid to control fluid flow through the at least one orifice, between first fluid chamber and the second fluid chamber; and
wherein the piezoelectric device engages the at least one valve disk to move the spring point, about which the at least one valve disk bends, radially outward relative to a longitudinal axis, to change the fluid pressure required to bend the at least one valve disk when the piezoelectric device is disposed in the engaged position.

10. The damping system set forth in claim 9 further comprising:
a rod supported by the housing and at least partially disposed within the interior chamber of the housing, wherein the piston assembly is attached to the rod;
wherein the piezoelectric device is disposed within the interior chamber of the housing, and is attached to the rod adjacent the piston assembly; and
wherein the piezoelectric device moves linearly along the longitudinal axis in response to the control signal, to move between the disengaged position and engaged position.

11. The damping system set forth in claim 9 wherein the piezoelectric device partially blocks the at least one orifice when disposed in the engaged position to reduce fluid flow through the at least one orifice.

Assignees

• Gm Global Tech Operations Llc

Inventors

• Mcguire Michael E
• Klein Gary
• Weddle Charles C
• Marble Robert P

Classifications

• F16K31/005

  Piezoelectric benders · CPC title

• F16F9/348

  Throttling passages in the form of annular discs {or other plate-like elements which may or may not have a spring action}, operating in opposite directions {or singly, e.g. annular discs positioned on top of the valve or piston body (F16F9/341, F16F9/3415 take precedence)} · CPC title

• B60G2202/24

  Fluid damper · CPC title

• B60G13/08

  hydraulic · CPC title

• B60G17/08

  Characteristics of fluid dampers (adjusting fluid dampers in general F16F9/44 - F16F9/53) · CPC title