Damper assembly and a method of forming the damper assembly

A damper assembly includes a housing. A method of forming a damper assembly includes extruding the housing formed of aluminum. The housing defines a first chamber and a first passage spaced from each other, with a first inlet fluidly connecting the first chamber and the first passage. A piston is disposed in the first chamber and is movable in a first direction and a second direction opposite the first direction. A first restrictor valve is disposed in the first passage. The first restrictor valve is configured to restrict a flow of liquid into the first passage from the first chamber and the first inlet as the piston moves in one of the first and second directions which causes the liquid in the first chamber to increase a pressure applied to a first side of the piston to dampen movement of the piston.

TECHNICAL FIELD

The present disclosure relates to a damper assembly and a method of forming the damper assembly.

BACKGROUND

Damper assemblies are used in vehicle suspension systems to dissipate energy from road forces applied to the vehicle wheels as the vehicle travels over a road. Generally, the damper assemblies control the transfer of forces to the sprung mass of the vehicle. Dampers act between the vehicle wheels and sprung mass to control the energy transfer to the vehicle frame and body while maintaining contact between the tires and the road.

Monotube dampers utilize a single tube, with a piston assembly movable within the tube. The piston assembly is connected to the vehicle body, and the single tube of the damper is coupled to a tire and wheel assembly. A piston-rod of the piston assembly moves within the single tube and a portion of the rod of the piston-rod extends out of the tube. A gas chamber with a floating piston of the piston assembly is housed at an end of the single tube opposite a rod end of the piston-rod. The floating piston separates a gas chamber of the single tube and a fluid-filled chamber of the single tube. The floating piston moves to accommodate the volume displacement caused by the moving piston-rod. The gas chamber is filled with a gaseous fluid and the fluid-filled chamber is filled with a liquid. Some of the gaseous fluid can be stored in the gas chamber being located in a separate container from the single tube, and this gaseous fluid is fluidly connected to the single tube proximal to the end of the single tube opposite the rod end.

Twintube dampers utilize a pair of tube which are positioned concentric to each other. Therefore, an inner tube is nested or surrounded by an outer tube, and these tubes are in fluid communication with each other. Specifically, the inner and outer tubes are concentric to each other. The inner tube is filled with a liquid and the outer tube is partially filled with the liquid and partially filled with a gaseous fluid. Therefore, the outer tube presents a gas chamber. A piston assembly is movable within the inner tube. The piston assembly is connected to the vehicle body, and the twintube of the damper is coupled to a tire and wheel assembly. A piston-rod moves within the inner tube and a portion of the rod of the piston-rod extends out of the tube.

For the monotube, pressurized gas in the gas chamber requires a static pressure level commensurate with a desired damping ability of the damper assembly. Seals within the damper, such as a seal around the moving rod of the piston-rod, is designed in accordance with the static and dynamic range of pressures. A high static pressure level and tight rod seal will contribute to friction against the moving rod.

Some suspension systems are passive, so that pre-load, spring rate, and ride height of the vehicle are nonadjustable, single predetermined values determined by the design of the damper assembly. In some systems, pre-load, spring rate, and ride height are variable, but not all in a controlled manner. Other suspension systems are actively controlled, so that the spring rate or the preload of the vehicle can be varied. One active design utilizes a monotube damper with an external accumulator.

SUMMARY

The present disclosure provides a damper assembly including a housing. The housing defines a first chamber and a first passage spaced from each other. The housing also defines a first inlet that fluidly connects the first chamber and the first passage. The first chamber, the first passage and the first inlet are each configured to contain a liquid. The damper assembly includes a piston disposed in the first chamber and is movable in a first direction and a second direction opposite the first direction. The piston is configured to displace the liquid during movement in the first and second directions. The damper assembly further includes a first restrictor valve disposed in the first passage. The first restrictor valve is configured to restrict a flow of the liquid into the first passage from the first chamber and the first inlet as the piston moves in one of the first and second directions which causes the liquid in the first chamber to increase a pressure applied to a first side of the piston to dampen movement of the piston.

The present disclosure also provides a method of forming a damper assembly. The method includes extruding a housing formed of aluminum, with the housing defining a first chamber and a first passage spaced from each other. The method also includes milling a first distal end of the housing to partially form a first inlet that fluidly connects the first chamber and the first passage. The method further includes disposing a piston in the first chamber and inserting a first restrictor valve in the first passage.

The detailed description and the drawings or Figures are supportive and descriptive of the disclosure, but the claim scope of the disclosure is defined solely by the claims. While some of the best modes and other embodiments for carrying out the claims have been described in detail, various alternative designs and embodiments exist for practicing the disclosure defined in the appended claims.

DETAILED DESCRIPTION

Those having ordinary skill in the art will recognize that terms such as “above”, “below”, “upward”, “up”, “downward”, “down”, “top”, “bottom”, “left”, “right”, “back”, “forth”, “vertical”, “horizontal”, etc., are used descriptively for the figures, and do not represent limitations on the scope of the disclosure, as defined by the appended claims. As such, all directional references (e.g., the terms in the above sentence) are only used for identification purposes to aid the reader's understanding, and do not create limitations, particularly as to the position, orientation, or use of the disclosure. Furthermore, the term “substantially” can refer to a slight imprecision or slight variance of a condition, quantity, value, or dimension, etc., some of which that are within manufacturing variance or tolerance ranges that can be subject to human error.

Referring to the Figures, wherein like numerals indicate like or corresponding parts throughout the several views, a damper assembly10is generally shown inFIG. 1. The damper assembly10can be utilized with a vehicle or a non-vehicle. Non-limiting examples of the damper assembly10being utilized with the vehicle can include an automotive vehicle, such as, a car, a sports car, a truck, a motorcycle, etc. Furthermore, the vehicle can be a hybrid vehicle utilizing an internal combustion engine and one or more motor-generators. Additionally, the vehicle can be an electric vehicle utilizing one or more motor-generators and eliminating the internal combustion engine. As another example, the vehicle can be a vehicle utilizing the internal combustion engine and eliminating the motor-generator(s). It is to be appreciated that the vehicle can alternatively be a non-automotive vehicle such as boats, etc. Non-limiting examples of the damper assembly10being utilized with the non-vehicle can include machines, industrial machines, platforms for test equipment, platforms for other equipment or machines, etc.

Continuing withFIG. 1, the vehicle includes a structure12. The structure12can be one or more of: a chassis, a support structure12, a frame, a subframe, a body, a brace, a panel, an outer skin, etc. The structure12can be any suitable configuration. Additionally, the structure12can be any component of a sprung mass of the vehicle, including the body, the frame, the subframe, the chassis, the outer skin, or any load-bearing component which is supported by a suspension system (discussed immediately below).

Furthermore, the damper assembly10can be utilized with the suspension system. Generally, the suspension system can dampen movement of the structure12as the vehicle travels over a road14(seeFIG. 1) or the ground to provide a smoother ride. The suspension system supports the structure12and the structure12is spaced from the road14. The suspension system can also dissipate energy and dampen movement of the unsprung mass. Examples of the unsprung mass can be wheels16, tires, brakes, etc.

The suspension system can include the damper assembly10or a plurality of damper assemblies10to dampen movement of the structure12. The damper assembly10can dissipate energy from travelling over the road14without causing excess transmission of energy to the structure12, which thus, provides a smoother ride for the vehicle occupants. Various configurations of the damper assembly10are discussed below, and it is to be appreciated that one or more of the damper assemblies10described below can be utilized with the suspension system.

Continuing withFIG. 1, the vehicle can include a wheel16rotatably supported by a knuckle18or a hub. The wheel16is shown in phantom lines for illustrative purposes only. The knuckle18can be coupled to the structure12by at least one link. For example, in certain embodiments, the knuckle18is coupled to the structure12by a first link20and a second link22. Generally, the first link20is coupled to an upper portion24of the knuckle18and the second link22is coupled to a lower portion26of the knuckle18.

In certain embodiments, the damper assembly10can be coupled or attached to the second link22and coupled or attached to the structure12. The damper assembly10and the first and second links20,22can cooperate with the structure12in various orientations, some of which can be referred to as a short long arm (SLA) suspension, a solid axle suspension, a multi-link suspension, struts, or any suitable suspension system arrangement. Therefore, the damper assembly10can be coupled or attached to the knuckle18and the structure12in suspension arrangements such as the SLA suspension, the solid axle suspension, the multi-link suspension, struts, etc.

In one of these alternative suspension arrangements, the suspension system can include a tower mount coupled or attached to the structure12, and the damper assembly10is coupled or attached to the tower mount and the upper portion24of the knuckle18. In this alternative arrangement, the first link20can be eliminated.

Generally, the damper assembly10is packaged between the wheel16and the structure12of the vehicle. The features of the damper assembly10are configured to provide compact packaging of the damper assembly10to minimize the space utilized between the wheel16and the structure12.

Referring toFIGS. 1-3, 11 and 12, the damper assembly10includes a housing28. The housing28is configured to minimize the space utilized between the wheel16and the structure12.FIGS. 2 and 3illustrate one configuration of the housing28andFIGS. 11 and 12illustrate another configuration of the housing28. It is to be appreciated that the housing28can be other configurations than illustrated. Furthermore, the housing28can be orientated in various different ways andFIG. 1is one example.

Referring toFIG. 1, the housing28can include a first distal end30and a second distal end32spaced from each other along an axis34. In certain embodiments, the housing28is orientated such that the first distal end30is disposed proximal to the second link22(as shown inFIG. 1). In other embodiments, the housing28is orientated such that the second distal end32is disposed proximal to the second link22. In other words, the orientation of the housing28can be reversed. In yet other embodiments, the housing28can be orientated such that the first distal end30or the second distal end32is coupled or attached to the upper portion24of the knuckle18.

The damper assembly10can optionally include a coil spring36(seeFIG. 1). The coil spring36can be in any suitable location when utilized. The coil spring36can surround the housing28in certain embodiments, andFIG. 1illustrates one example of that. In other configurations, the coil spring36does not surround the housing28.

Referring toFIGS. 3-5 and 12, the housing28defines a first chamber38and a first passage40spaced from each other. Generally, the first chamber38and the first passage40are substantially parallel to each other in a non-concentric orientation. In other words, the first chamber38and the first passage40are not concentric to each other. Having the first chamber38and the first passage40being substantially parallel to each other allows the housing28to be formed of extruded aluminum in a cost effective way. It is to be appreciated that the housing28can be formed of materials other than aluminum, and non-limiting examples can include steel, polymers, plastic, composites, etc.

As best shown inFIGS. 3-5 and 9, the housing28also defines a first inlet42that fluidly connects the first chamber38and the first passage40. Generally, the first inlet42extends between the first chamber38and the first passage40. Therefore, the first inlet42is disposed transverse to the first chamber38and the first passage40.

The first chamber38, the first passage40and the first inlet42are each configured to contain a liquid44. Generally, the liquid44is a non-compressible fluid. For example, the liquid44can be oil; mineral oil; silicon based fluid; a smart fluid, such as an electrorheological (ER) fluid, magnetorheological (MR) fluid, etc.; hydraulic oil; hydraulic fluid; any suitable shock oil as known to those skilled in the art; etc.

Referring toFIGS. 4-6 and 14, the damper assembly10further includes a piston46disposed in the first chamber38. The piston46is movable in a first direction and a second direction opposite the first direction. The piston46displaces the liquid44during movement in the first and second directions. Movement of the piston46in the first direction can be toward the first distal end30of the housing28(seeFIG. 4) and movement of the piston46in the second direction can be toward the second distal end32of the housing28(seeFIG. 5). In other embodiments, the first direction can be toward the second distal end32and the second direction can be toward the first distal end30depending on the orientation of various components of the damper assembly10. Generally, when the piston46moves in the first direction, this can be referred to as compression of the damper assembly10, and when the piston46moves in the second direction, this can be referred to as rebound of the damper assembly10.

Optionally, a first seal48can be disposed between the piston46and an inner wall50of the first chamber38to minimize the liquid44from moving therebetween as the piston46moves. Furthermore, optionally, the piston46can include one or more valves, or define one or more orifices, that allow a small amount of the liquid44to flow therethrough as the piston46moves in the first and second directions.

Continuing withFIGS. 4-6 and 14, the damper assembly10can also include a rod52extending from the piston46. The rod52can be partially disposed inside the first chamber38and partially disposed outside of the first chamber38. The rod52and the piston46can be attached to each other or integrally formed as a one-piece unit. Therefore, the rod52and the piston46move in unison or simultaneously.

The damper assembly10can further include a rod seal54disposed about the rod52. In other words, the rod seal54surrounds the rod52. The rod seal54is coupled to the housing28to maintain the position of the rod seal54relative to the housing28as the rod52moves with the piston46. Generally, the rod52moves relative to the rod seal54. The rod seal54prevents the liquid44from leaking out between the housing28and the rod52. Pressure and friction is applied to the rod seal54as the rod52and the piston46moves in the first and second directions. The configuration of the damper assembly10reduces the amount of pressure and friction applied to the rod seal54, which is discussed further below.

Turning back toFIG. 1, the rod52can include a first connector end56coupled or attached to the structure12, or coupled or attached to the second link22depending on the orientation of the piston46and the rod52relative to the structure12. Therefore, in various embodiments, the first connector end56is attached or coupled to the structure12, and in other embodiments, the first connector end56is attached or coupled to the second link22. In yet other embodiments, the first connector end56can be attached or coupled to other components of the suspension system depending on the suspension arrangement being utilized. As identified above, the structure12can include many different components, and the first connector end56of the rod52can be coupled or attached to any suitable component of the structure12. It is to be appreciated that the first connector end56of the rod52can be coupled or attached to the structure12, the second link22, etc., by any suitable methods, such as fasteners (as shown inFIG. 1for illustrative purposes only), couplers, pins, etc.

Generally, the first connector end56of the rod52is spaced from the piston46and disposed outside of the housing28. It is to be appreciated that a dust cover or an external tube can surround the rod52, the first connector end56of the rod52and/or the housing28, but for illustrative purposes, is not shown in the Figures.

Turning toFIGS. 4, 5, 7, 9, 15 and 17, the damper assembly10also includes a first restrictor valve58disposed in the first passage40. The first restrictor valve58is configured to restrict a flow of the liquid44into the first passage40from the first chamber38and the first inlet42as the piston46moves in one of the first and second directions which causes the liquid44in the first chamber38to increase a pressure applied to a first side60of the piston46to dampen movement of the piston46. For example, the first restrictor valve58can restrict the flow of the liquid44into the first passage40from the first chamber38when the piston46moves in the first direction, i.e., compression. In certain embodiments, the first side60of the piston46can face the first distal end30of the housing28. Dampening movement of the piston46correspondingly dampens movement of the structure12which provides a smoother ride along the road14. The first restrictor valve58can also be referred to as a metering valve or a regulating valve. Furthermore, the first restrictor valve58can be an adaptive valve or passive valve. Non-limiting examples of the adaptive valve can include a solenoid valve, a magnetorheological (MR) valve, an electrorheological (ER) valve. A non-limiting example of the passive valve is the valve defines an orifice and includes a pre-loaded spring blow-off element(s).

Referring toFIGS. 3-5, 9 and 12, the housing28can define a first outlet62that fluidly connects the first chamber38and the first passage40. Generally, the first outlet62extends between the first chamber38and the first passage40. Therefore, the first outlet62is disposed transverse to the first chamber38and the first passage40. The first outlet62is configured to contain the liquid44. The first passage40is fluidly connected to the first chamber38in two locations, i.e., through the first inlet42and the first outlet62. Generally, the first inlet42and the first outlet62are spaced from each other. For example, the first inlet42can be disposed proximal to the first distal end30of the housing28and the first outlet62can be disposed proximal to the second distal end32of the housing28. In certain situations, which will be discussed further below, some of the liquid44enters the first passage40through the first inlet42and exits the first passage40through the first outlet62.

Referring toFIGS. 4, 5, 7, 9, 15 and 17, the damper assembly10can further include a first one-way valve64disposed in the first passage40. Generally, the first one-way valve64allows the flow of liquid44in one direction and prevents the flow of the liquid44in an opposite direction. Therefore, the first one-way valve64is disposed in the first passage40to prevent the flow of the liquid44into the first passage40from the first outlet62. Specifically, the first one-way valve64can be disposed in the first passage40to allow the liquid44to exit the first passage40through the first one-way valve64while preventing the liquid44from flowing into the first passage40from the first outlet62. Therefore, once the liquid44exits the first one-way valve64to the first outlet62, the liquid44cannot enter the first one-way valve64from the first outlet62. In certain embodiments, the first restrictor valve58can be disposed proximal to the first inlet42and the first one-way valve64can be disposed proximal to the first outlet62. The first one-way valve64can also be referred to as a check valve.

Referring toFIGS. 3 and 12, the housing28can define a second chamber66and a second passage68spaced from each other. The second chamber66accommodates for thermal expansion of the liquid44as the piston46moves in the first and second directions. As the piston46displaces the liquid44during movement, heat is created which causes thermal expansion of the liquid44, and the second chamber66accommodates this thermal expansion. Optionally, an outer wall70of the housing28can include a plurality of fins spaced from each other for cooling purposes or heat transfer purposes.

Generally, the second chamber66and the second passage68are substantially parallel to each other in a non-concentric orientation. In other words, the second chamber66and the second passage68are not concentric to each other. Having the second chamber66and the second passage68being substantially parallel to each other allows the housing28to be formed of extruded aluminum in a cost effective way. The schematic circuit illustration of the second chamber66inFIG. 13can replace the second chamber66illustrated inFIGS. 4 and 5.

Furthermore, in certain embodiments, as shown inFIGS. 3 and 12, the first and second chambers38,66and the first and second passages40,68are substantially parallel to each other in a non-concentric orientation. In other words, the first and second chambers38,66and the first and second passages40,68are not concentric to each other. Having the first and second chambers38,66and the first and second passages40,68being substantially parallel to each other allows the housing28to be formed of extruded aluminum in a cost effective way.

Furthermore, referring toFIGS. 3-5, 10 and 12, the housing28can define a second inlet72that fluidly connects the first chamber38and the second passage68. Generally, the second inlet72extends between the first chamber38and the second passage68. Therefore, the second inlet72is disposed transverse to the first chamber38and the second passage68. The second chamber66, the second passage68and the second inlet72are each configured to contain the liquid44.

Referring toFIGS. 4-6, 13 and 14, the second chamber66is also configured to contain a gaseous fluid74. The second chamber66is split into a liquid fluid side which contains some of the liquid44and a gaseous fluid side which contains the gaseous fluid74. The gaseous fluid74can be an inert gaseous fluid74, air, nitrogen, any other suitable gaseous fluid74, etc.

Turning toFIGS. 4-8 and 12-18, the damper assembly10can further include a member76disposed in the second chamber66. The member76is at least partially movable in the second chamber66as the piston46moves in the first and second directions. The member76moves in response to pressure applied thereto due to movement of the piston46between the first and second directions. Generally, the member76moves to further compress the gaseous fluid74when the piston46moves in the first direction (seeFIG. 4) and the member76moves in the opposite direction to decompress the gaseous fluid74when the piston46moves in the second direction (seeFIG. 5).

The member76splits the second chamber66into a first cavity78and a second cavity80. The first cavity78is configured to contain some of the liquid44and the second cavity80is configured to contain the gaseous fluid74. Therefore, the liquid fluid side is the first cavity78and the gaseous fluid side is the second cavity80. The member76can be various configurations and a couple different examples are discussed below for illustrative purposes only. It is to be appreciated that the member76can be other configurations than discussed herein.

In certain embodiments, as shown inFIGS. 4-8, the member76is formed of a rigid material such that the member76substantially maintains its configuration. The entire member76of this embodiment can be movable in the second chamber66in response to movement of the piston46in the first chamber38. Optionally, a second seal82can be disposed between the member76and an inner wall84of the second chamber66to minimize leaking of the liquid44and the gaseous fluid74therebetween. In other words, the second seal82about the member76assist in maintaining the liquid44in the first cavity78and the gaseous fluid74in the second cavity80, i.e., minimizes mixing of the liquid and gaseous fluid44,74. This member76can be a referred to as a floating piston46or cup.

In other embodiments, as shown inFIGS. 12-18, the member76is at least partially formed of a flexible material such that at least part of the member76can be movable in the second chamber66in response to movement of the piston46in the first chamber38. This member76can be referred to as a membrane or non-permeable membrane to maintain separation between the gaseous fluid74and the liquid44.

The member76ofFIGS. 12-18can also include a plurality of anchors86spaced from each other. One anchor86is disposed proximal to one edge88of the member76and another anchor86is disposed proximal to another edge88of the member76. The anchors86secure the member76to the inside of the second chamber66such that a portion of the member76can remain stationary as another portion of the member76moves in response to the movement of the piston46in the first chamber38. The anchors86can be any suitable configuration andFIG. 12illustrates one example with the anchors86surrounded by the flexible material. The anchors86can be a rigid material. For example, the anchors86can be wire, hard plastic, etc.

Referring toFIGS. 3-5, 7, 12 and 15, the housing28can define a first pathway90disposed between the first restrictor valve58and the first one-way valve64to fluidly connect the first passage40and the second chamber66. Generally, the first pathway90extends between the second chamber66and the first passage40. Therefore, the first pathway90is disposed transverse to the second chamber66and the first passage40. The first pathway90is also configured to contain the liquid44.

Turning toFIGS. 4, 5, 8, 10, 16 and 18, the damper assembly10can further include a second restrictor valve92disposed in the second passage68. The second restrictor valve92is configured to restrict the flow of the liquid44into the second passage68as the piston46moves in the other one of the first and second directions which causes the liquid44in the first chamber38to increase a pressure applied to a second side94of the piston46to dampen movement of the piston46. For example, the second restrictor valve92can restrict the flow of the liquid44into the second passage68from the first chamber38when the piston46moves in the second direction, i.e., rebound. In certain embodiments, the second side94of the piston46can face the second distal end32of the housing28. Dampening movement of the piston46correspondingly dampens movement of the structure12which provides a smoother ride along the road14. The second restrictor valve92can be referred to as a metering valve or a regulating valve. Furthermore, the second restrictor valve92can be an adaptive valve or passive valve. Non-limiting examples of the adaptive valve of the second restrictor valve92can include a solenoid valve, a magnetorheological (MR) valve, an electrorheological (ER) valve. A non-limiting example of the passive valve of the second restrictor valve92is the valve defines an orifice and includes a pre-loaded spring blow-off element(s).

Referring toFIGS. 4, 5 and 10, the housing28can define a second outlet96that fluidly connects the first chamber38and the second passage68. Generally, the second outlet96extends between the first chamber38and the second passage68. Therefore, the second outlet96is disposed transverse to the first chamber38and the second passage68. The second outlet96is configured to contain the liquid44. The second passage68is fluidly connected to the first chamber38in two locations, i.e., through the second inlet72and the second outlet96. Generally, the second inlet72and the second outlet96are spaced from each other. For example, the second inlet72can be disposed proximal to the second distal end32of the housing28and the second outlet96can be disposed proximal to the first distal end30of the housing28. In certain situations, which will be discussed further below, some of the liquid44enters the second passage68through the second inlet72and exits the second passage68through the second outlet96.

Turning toFIGS. 4, 5, 8, 10, 16 and 18, the damper assembly10can also include a second one-way valve98disposed in the second passage68. Generally, the second one-way valve98allows the flow of liquid44in one direction and prevents the flow of the liquid44in an opposite direction. Therefore, the second one-way valve98is disposed in the second passage68to prevent the flow of the liquid44into the second passage68from the second outlet96. Specifically, the second one-way valve98can be disposed in the first passage40to allow the liquid44to exit the second passage68through the second one-way valve98while preventing the liquid44from flowing into the second passage68from the second outlet96. Therefore, once the liquid44exits the second one-way valve98to the second outlet96, the liquid44cannot enter the second one-way valve98from the second outlet96. In certain embodiments, the second restrictor valve92can be disposed proximal to the second inlet72and the second one-way valve98can be disposed proximal to the second outlet96. The second one-way valve98can also be referred to as a check valve.

Referring toFIGS. 3-5, 8, 12 and 16, the housing28can also define a second pathway100disposed between the second restrictor valve92and the second one-way valve98to fluidly connect the second passage68and the second chamber66. Generally, the second pathway100extends between the second chamber66and the second passage68. Therefore, the second pathway100is disposed transverse to the second chamber66and the second passage68. The second pathway100is also configured to contain the liquid44.

Turning toFIGS. 2, 6-11 and 14-18, the housing28can include a plurality of caps102to close the first and second chambers38,66of the housing28and the first and second passages40,68of the housing28. The caps102can assist in improving the assembly process of the damper assembly10. Any suitable number of caps102can be utilized and some examples are discussed below.

For example, in certain embodiments, one of the caps102can be defined as a first cap102that can be utilized to close a first end104of the first chamber38. Furthermore, in certain embodiments, the first cap102can close a first end106of the second chamber66. Additionally, in certain embodiments, the first cap102can close a first end108of the first passage40and a first end110of the second passage68. As shown inFIGS. 9 and 10, one of the caps102, such as the first cap102, can define a portion of the first inlet42and a portion of the second outlet96, which can make the assembly process more efficient.

Alternatively, the first cap102can close the first ends104,106of the first and second chambers38,66, another cap102can close the first end108of the first passage40and yet another cap102can close the first end110of the second passage68. As another alternative, one cap102can close the first end104of the first chamber38, another cap102can close the first end106of the second chamber66, yet another cap102can close the first end108of the first passage40and another cap102can close the first end110of the second passage68. As yet another alternative, one cap102can be utilized for one or more of the first ends104,106of the first and second chambers38,66, and another cap102can be utilized for one or more of the first ends108,110of the first and second passages40,68. Any other combination of caps102cooperating with the first ends104,106,108,110of the chambers38,66/passages40,68can be utilized.

As another example, in certain embodiments, one of the caps102can be defined as a second cap102that can be utilized to close a second end112of the first chamber38. Furthermore, in certain embodiments, the second cap102can close a second end114of the second chamber66. Additionally, in certain embodiments, the second cap102can close a second end116of the first passage40and a second end118of the second passage68. The second cap102that closes the second end112of the first chamber38can define an opening120for the rod52of the piston46to extend therethrough. Furthermore, the rod seal54is disposed in the opening120to minimizing leaking of the liquid44out of the opening120. As shown inFIGS. 9 and 10, one of the caps102, such as the second cap102, can define a portion of the first outlet62and a portion of the second inlet72, which can make the assembly process more efficient. For example, a minimum of two caps102can be utilized with the housing28ofFIGS. 11 and 12.

Alternatively, the second cap102can close the second ends112,114of the first and second chambers38,66, another cap102can close the second end116of the first passage40and yet another cap102can close the second end118of the second passage68. As another alternative, one cap102can close the second end112of the first chamber38, another cap102can close the second end114of the second chamber66, yet another cap102can close the second end116of the first passage40and another cap102can close the second end118of the second passage68. As yet another alternative, one cap102can be utilized for one or more of the second ends112,114of the first and second chambers38,66, and another cap102can be utilized for one or more of the second ends116,118of the first and second passages40,68. Any other combination of caps102cooperating with the second ends112,114,116,118of the chambers38,66/passages40,68can be utilized.

In certain embodiments, one of the caps102can be defined as a third cap102that can be utilized to close the second end114of the second chamber66. Therefore, in various embodiments, the second cap102can close at least the second end112of the first chamber38and the third cap102can close the second end114of the second chamber66. For example, a minimum of three caps102can be utilized with the housing28ofFIGS. 2 and 3.

In various embodiments, one of the caps102can include a second connector end122(seeFIGS. 9 and 10) which couples the first distal end30of the housing28to the structure12, the second link22or any other component depending on the configuration of the suspension system discussed above. Any of the caps102can include the second connector end122depending on the configuration or orientation of the suspension system. By incorporating the second connector end122into one of the caps102, this can reduce the number of assembly parts and reduce assembly time. The second connector end122can include an eye ring or clevis, etc.

Referring toFIGS. 15-18, one or more of the caps102can be configured to wedge or pinch a portion of the member76between a wall of the housing28in the second chamber66and that cap102. Generally, these configurations of the caps102cooperate with the membrane configuration of the member76and ensure a desired preload is applied to the member76. The caps102can include a tapered portion, a flat portion or any other suitable configuration to wedge or pinch the member76between the wall of the housing28in the second chamber66and that cap102.

The damper assembly10features discussed above can be for a passive suspension system. Passive suspension systems do not allow the spring rate or the preload of the damper assembly10to be variable during operation of the vehicle. Furthermore, passive suspension systems do not allow the amount of damping of the damper assembly10to be variable during operation of the vehicle. Therefore, once the desired amount of damping is determined and the components assembled according to the desired amount of damping, the damper assembly10will dampen movement of the sprung mass according to that pre-set amount.

The operation of the passive damper assembly10will be briefly discussed below for illustrative purposes. When the vehicle travels over, for example, a bump, the suspension system reacts to dampen movement of the vehicle to provide a smooth ride. Specifically, the damper assembly10will react to dampen movement of the vehicle. The location of the first passage40having the first restrictor and one-way valves58,64disposed therein and location of the second passage68having the second restrictor and one-way valves92,98disposed therein allows for independent control of the piston46, as the piston46moves in the first and second directions. The configuration and location of the valves58,64,92,98also provides the ability to check the valves58,64,92,98off-line and/or calibrate the valves58,64,92,98prior to assembling all of the components of the damper assembly10.

The piston46of the damper assembly10will move back and forth in the housing28in response to the bump. Referring toFIG. 4, when the piston46moves in the first direction, i.e., compression, which is toward the first distal end30of the housing28, the liquid44is displaced and some of this liquid44is forced through the first restrictor valve58and into the first passage40. The displaced liquid44can either continue through the first pathway90into the second chamber66or out of the first one-way valve64. The arrows inFIG. 4illustrate the paths of flow of the displaced liquid44when the piston46moves in the first direction. As the liquid44enters the second chamber66, the member76moves to compress the gaseous fluid74, as the second chamber66accommodates for thermal expansion due to the movement of the piston46. When the piston46moves in the first direction, the liquid44is not displaced into the second passage68. As such, the operation of the damper assembly10, when the piston46moves in the first direction, occurs with the first restrictor valve58and the first one-way valve64. The first restrictor valve58provides a pressure drop from the first chamber38to the first passage40which reduces a gas charge applied to the second chamber66. Reducing the gas charge in turn reduces the amount of pressure and friction applied to the rod seal54.

Referring toFIG. 5, when the piston46moves in the second direction, i.e., rebound, which is toward the second distal end32of the housing28, the liquid44is displaced and some of this liquid44is forced through the second restrictor valve92and into the second passage68. The displaced liquid44can either continue through the second pathway100into the second chamber66or out of the second one-way valve98. The arrows inFIG. 5illustrate the paths of flow of the displaced liquid44when the piston46moves in the second direction. Less liquid44enters the second chamber66when the piston46moves in the second direction which allows the member76to move to decompress the gaseous fluid74. When the piston46moves in the second direction, the liquid44is not displaced into the first passage40. As such, the operation of the damper assembly10, when the piston46moves in the second direction, occurs with the second restrictor valve92and the second one-way valve98. The second restrictor valve92provides a pressure drop from the first chamber38to the second passage68which reduces the gas charge applied to the second chamber66. Reducing the gas charge in turn reduces the amount of pressure and friction applied to the rod seal54.

The damper assembly10can further include features that allow the damping of the vehicle to be variable. For example, the damper assembly10discussed above can include other features that cause the damper assembly10to be for an adaptive suspension system instead of the passive suspension system. Adaptive suspension systems allow the amount of damping of the sprung mass of the vehicle to be varied. However, adaptive suspension systems do not allow the spring rate or the preload of the damper assembly10to be variable during operation of the vehicle. The features of the adaptive suspension system are discussed immediately below.

Optionally, in certain embodiments, as shown inFIG. 17, the damper assembly10can include a first electrorheological (ER) valve124disposed in the first passage40between the first restrictor valve58and the first one-way valve64. The first ER valve124is also shown in phantom lines inFIGS. 4, 5, 9 and 19for illustrative purposes as an optional feature for the damper assembly10. Therefore, the first ER valve124can be utilized in any of the embodiments described herein. The phantom lines generally indicate where the first ER valve124could be located. The first ER valve124is selectively energized to selectively restrict the flow of the liquid44through the first passage40which causes the liquid44in the first chamber38to increase the pressure applied to the first side60of the piston46to dampen movement of the piston46. Therefore, the first ER valve124can be in an energized state or a de-energized state.

Optionally, in certain embodiments, as shown inFIG. 18, the damper assembly10can further include a second electrorheological (ER) valve126disposed in the second passage68between the second restrictor valve92and the second one-way valve98. The second ER valve126is also shown in phantom lines inFIGS. 4, 5, 10 and 19for illustrative purposes as an optional feature for the damper assembly10. Therefore, the second ER valve126can be utilized in any of the embodiments described herein. The phantom lines generally indicate where the second ER valve126could be located. The second ER valve126is selectively energized to selectively restrict the flow of the liquid44through the second passage68which causes the liquid44in the first chamber38to increase the pressure applied to the second side94of the piston46to dampen movement of the piston46. Therefore, the second ER valve126can be in an energized state or a de-energized state.

Referring toFIGS. 17 and 18, the first and second ER valves124,126can each include a casing128containing the liquid44that has properties the can change the shear strength of the liquid44in certain situations, i.e., can be referred to as the smart liquid44. The first and second ER valves124,126can each include a plurality of particles130contained in the casing128. The particles130are disposed in the liquid44, and therefore, located in the same places where the liquid44is located in the housing28, e.g., the first chamber38, the liquid fluid side of the second chamber66, the first passage40, the second passage68, etc. For example, the particles130can be formed of a polymer and one suitable polymer is plastic. The smart liquid44can be a silicone based fluid or any other suitable type of smart liquid44.

Continuing withFIGS. 17 and 18, the first and second ER valves124,126can each include an electrode132that can create an electric field when a current is applied to the electrode132. The casing128at least partially surrounds the electrode132. In other words, the electrode132is at least partially disposed inside the casing128. When the electric field is created, the particles130and the smart liquid44interact to change the shear strength of the smart liquid44within the casing128.

When the first and second ER valves124,126are energized, the electrode132creates the electric field and the shear strength of the smart liquid44increases, which increases the resistance on the liquid44traveling through the first and second ER valves124,126, which thus restricts the flow of the liquid44. Therefore, when the first ER valve124is energized, the flow of the liquid44into the first passage40is restricted, and when the second ER valve126is energized, the flow of the liquid44into the second passage68is restricted.FIG. 18illustrates when the electric field is being created and the particles130are organized generally in rows or chains between the electrode132and the casing128of respective ER valves124,126, i.e., the energized state.

When the first and second ER valves124,126are de-energized, the electrode132does not create the electric field and the shear strength of the smart liquid44decreases, which creates less resistance on the liquid44traveling through the first and second ER valves124,126. Therefore, when the first ER valve124is de-energized, the flow of the liquid44into the first passage40is less restricted than when the valve124is energized, and when the second ER valve126is de-energized, the flow of the liquid44into the second passage68is less restricted than when the valve126is energized.FIG. 17illustrates when no electric field is being created and the particles130are unorganized in the smart liquid44, i.e., the de-energized state.

Referring toFIGS. 17 and 18, the first and second ER valves124,126can each include a power source134that is electrically connected to respective electrodes132to selective energize the respective electrode132. The cross-sectional views ofFIGS. 17 and 18can be similarly taken fromFIG. 11with the addition of respective power sources134being coupled to the outside of the housing28, which is not shown inFIG. 11. Therefore,FIG. 11is illustrative of the damper assembly10that can be utilized without the first and second ER valves124,126, and is illustrative of the damper assembly10that can utilize the first and second ER valves124,126.

Referring toFIGS. 17 and 18, a controller136can be in communication with the power source134of the first and second ER valves124,126to selectively energize respective electrodes132. It is to be appreciated that a plurality of controllers136can be utilized. For example, one controller136can be in communication with the electrode132of the first ER valve124and another controller136can be in communication with the electrode132of the second ER valve126. As another example, one controller136can be in communication with the electrode132of the first ER valve124, another controller136can be in communication with the electrode132of the second ER valve126and yet another controller136can be in communication with both of the controllers136. As yet another example, one controller136can be in communication with the power source134of both the first and second ER valves124,126.

The controller(s)136can be part of an electronic control module that is in communication with various components of the vehicle. The controller(s)136includes a processor138and a memory140on which is recorded instructions for communicating with the power sources134and optionally other components of the vehicle. The controller(s)136is configured to execute the instructions from the memory140, via the processor138. For example, the controller(s)136can be a host machine or distributed system, e.g., a computer such as a digital computer or microcomputer, acting as a vehicle control module having a processor and the memory140. The memory140can be tangible, non-transitory computer-readable memory such as read-only memory (ROM) or flash memory. The controller(s)136can also have random access memory (RAM), electrically erasable programmable read only memory (EEPROM), a high-speed clock, analog-to-digital (A/D) and/or digital-to-analog (D/A) circuitry, and any required input/output circuitry and associated devices, as well as any required signal conditioning and/or signal buffering circuitry. Therefore, the controller(s)136can include all software, hardware, memory140, algorithms, connections, sensors, etc., necessary to monitor and control the power sources134, etc. As such, a control method can be embodied as software or firmware associated with the controller(s)136. It is to be appreciated that the controller(s)136can also include any device capable of analyzing data from various sensors, comparing data, making the necessary decisions required to control and monitor the power sources134, etc.

Continuing withFIGS. 17 and 18, the first and second ER valves124,126can each include an insulator142to prevent the electric field from being created in other areas of the damper assembly10. The insulator142can surround the casing128, as well as the smart liquid44and the particles130inside the casing128. Furthermore, the insulator142can at least partially surround the electrode132. The insulator142can be formed of any suitable non-conductive material. For example, the insulator142can be formed of nylon, etc.

The damper assembly10of the adaptive suspension system can include the first and second ER valves124,126, and the corresponding features discussed above. Therefore, the damper assembly10of the adaptive suspension system includes the first and second restrictor valves58,92, the first and second one-way valves64,98and the first and second ER valves124,126.

The operation of the adaptive damper assembly10will be briefly discussed below for illustrative purposes. The difference between the passive damper assembly10and the adaptive damper assembly10is the adaptive damper assembly10further includes the first and second ER valves124,126. Therefore, the adaptive damper assembly10includes the piston46, the first and second restrictor valves58,92, the first and second one-way valves64,98and the second chamber66as discussed above, and the details of the operation of these components will not be re-discussed. The adaptive system adds the first and second ER valves124,126and the operation with these ER valves124,126will be discussed below.

Referring toFIG. 4, when the piston46moves in the first direction, i.e., compression, which is toward the first distal end30of the housing28, the liquid44is displaced and some of this liquid44is forced through the first restrictor valve58and then through the first ER valve124. The first ER valve124can be energized when the piston46moves in the first direction. The controller136communicates to the power source134and the power source134supplies the current to the electrode132of the first ER valve124which energizes that electrode132and creates the electric field. The electric field causes the particles130inside the first ER valve124to align in rows or chains, or become organized, which further restricts the flow of the liquid44. As the liquid44exits the first restrictor valve58and the first ER valve124, the displaced liquid44can either continue through the first pathway90into the second chamber66or out of the first one-way valve64. When the piston46moves in the first direction, the liquid44is not displaced into the second passage68. As such, when the piston46moves in the first direction, the second ER valve126is de-energized, and thus, the particles130inside the second ER valve126are unorganized when the second ER valve126is de-energized.

Referring toFIG. 5, when the piston46moves in the second direction, i.e., rebound, which is toward the second distal end32of the housing28, the liquid44is displaced and some of this liquid44is forced through the second restrictor valve92and then through the second ER valve126. The second ER valve126can be energized when the piston46moves in the second direction. The controller136communicates to the power source134and the power source134supplies the current to the electrode132of the second ER valve126which energizes that electrode132and creates the electric field. The electric field causes the particles130inside the second ER valve126to align in rows or chains, or become organized, which further restricts the flow of the liquid44. As the liquid44exits the second restrictor valve92and the second ER valve126, the displaced liquid44can either continue through the second pathway100into the second chamber66or out of the second one-way valve98. When the piston46moves in the second direction, the liquid44is not displaced into the first passage40. As such, when the piston46moves in the second direction, the first ER valve124is de-energized, and thus, the particles130inside the first ER valve124are unorganized when the first ER valve124is de-energized.

The damper assembly10can further include features that allow the damping, and/or the preload, of the vehicle to be variable and/or controlled. For example, the damper assembly10discussed above can include other features that allow the damper assembly10to be for an active suspension system instead of the passive or adaptive suspension system. Active suspension systems allow a spring rate or the preload of the damper assembly10to be variable during operation of the vehicle. Furthermore, the active suspension systems can allow the height of the structure12relative to the road14to be changed. Active suspension systems can improve vehicle handling. The features of the active suspension system are discussed immediately below.

Optionally, in certain embodiments, the damper assembly10can include an actuator144(seeFIG. 19) coupled to the second chamber66. The actuator144is shown in phantom lines in the schematic illustration ofFIG. 19. The actuator144can be utilized to change the spring rate of the suspension system and change the height of the structure12relative to the road14. The actuator144can be coupled to the housing28in various locations and three different locations are illustrated inFIG. 19. For example, the actuator144can be coupled to the gaseous fluid side of the second chamber66or the second cavity80of the second chamber66. As another example, the actuator144can be coupled to the liquid fluid side of the second chamber66or the first cavity78of the second chamber66. As yet another example, the actuator144can be coupled to the first chamber38.

In certain embodiments, the actuator144can include a plunger146selectively movable in the second chamber66to selectively change a pressure applied to the member76which changes the spring rate of the piston46. Furthermore, movement of the plunger146can move the member76in the second chamber66. Generally, the plunger146can be coupled to the gaseous fluid side of the second chamber66or the second cavity80of the second chamber66. The plunger146can be movable by a motor or any other suitable device to selectively move the plunger146. In this embodiment, the amount of liquid44in the housing28is not changed.

Alternatively, the actuator144is coupled to the first chamber38and selectively actuated to change an amount of the liquid44in the first chamber38which changes the spring rate of the piston46. Therefore, in this embodiment, the amount of liquid44in the housing28is changed. Meaning, the amount of the liquid44disposed in the housing28can be increased or decreased. In this embodiment, the plunger146of the actuator144is eliminated.

Yet another alternative, the actuator144is coupled to the liquid fluid side of the second chamber66or the first cavity78of the second chamber66and selectively actuated to change an amount of the liquid44in the second chamber66which changes the spring rate of the piston46. Therefore, in this embodiment, the amount of liquid44in the housing28is changed. Meaning, the amount of the liquid44disposed in the housing28can be increased or decreased. Changing the amount of liquid44in the second chamber66can move the member76in the second chamber66. In this embodiment, the plunger146of the actuator144is eliminated.

Generally, there is a fixed volume of the liquid44inside the housing28. However, when utilizing the actuator144that can add or remove the liquid44, the volume of the liquid44inside the housing28is variable, i.e., not fixed. The actuator144can be a hydraulic actuator, a pneumatic actuator or any other suitable actuator. When utilizing the pneumatic actuator, the actuator144can include an air accumulator to act as an air spring.

Referring toFIG. 19, a controller148can be in communication with the actuator144to selectively actuate the actuator144. Therefore, the controller148can signal the motor to move the plunger146or stop movement of the plunger146. Alternatively, the controller148can signal the actuator144to add liquid44into the first chamber38or the second chamber66. Furthermore, the controller148can signal the actuator144to remove some of the liquid44from the first chamber38or the second chamber66.

The controller148can be part of an electronic control module that is in communication with various components of the vehicle. The controller148includes a processor150and a memory152on which is recorded instructions for communicating with the actuator144and optionally other components of the vehicle. The controller148is configured to execute the instructions from the memory152, via the processor150. For example, the controller148can be a host machine or distributed system, e.g., a computer such as a digital computer or microcomputer, acting as a vehicle control module having a processor and the memory152. The memory152can be tangible, non-transitory computer-readable memory such as read-only memory (ROM) or flash memory. The controller148can also have random access memory (RAM), electrically erasable programmable read only memory (EEPROM), a high-speed clock, analog-to-digital (A/D) and/or digital-to-analog (D/A) circuitry, and any required input/output circuitry and associated devices, as well as any required signal conditioning and/or signal buffering circuitry. Therefore, the controller148can include all software, hardware, memory152, algorithms, connections, sensors, etc., necessary to monitor and control the actuator144, etc. As such, a control method can be embodied as software or firmware associated with the controller148. It is to be appreciated that the controller148can also include any device capable of analyzing data from various sensors, comparing data, making the necessary decisions required to control and monitor the actuator144, etc.

The operation of the active damper assembly10will be briefly discussed below for illustrative purposes. The difference between the active damper assembly10from the passive damper assembly10and the adaptive damper assembly10is the active damper assembly10further includes the actuator144. Therefore, the active damper assembly10includes the piston46, the first and second restrictor valves58,92, the first and second one-way valves64,98and the second chamber66as discussed above, and the details of the operation of these components will not be re-discussed. Optionally, the active damper assembly10can include the first and second ER valves124,126and the operation with these ER valves124,126will not be re-discussed.

The spring rate or preload can be changed during the operation of the vehicle or before/after operating the vehicle. Therefore, when it is desired to change the spring rate or preload, the actuator144is actuated. As such, actuation of the actuator144can occur before, during or after operating the piston46, the first and/or second restrictor valves58,92, the first and/or second one-way valves64,98, and optionally, the first and/or second ER valves124,126.

Changing the internal pressure of the actuator144controls the height of the vehicle, and thus adjusting the actuator144can automatically level the vehicle. By changing the internal pressure of the actuator144, the position of the rod52relative to the housing28changes which changes the height of the vehicle relative to the road14. For example, in certain embodiments, the controller148communicates with the actuator144to move the plunger146which changes the internal pressure of the actuator144, and thus changes the spring rate. When the plunger146moves to further compress the gaseous fluid74, the spring rate increases and when the plunger146moves to decompress the gaseous fluid74, the spring rate decreases. As another example, in certain embodiments, the controller148communicates with the actuator144which causes the amount of liquid44in the housing28to be changed which changes the internal pressure of the actuator144, and thus changes the spring rate. When some of the liquid44is added either to the second chamber66or the first chamber38, the spring rate increases and when some of the liquid44is removed from the second chamber66or the first chamber38, the spring rate decreases. When the desired spring rate is achieved, the actuator144is de-activated.

The present disclosure also provides a method of forming the damper assembly10. By forming the damper assembly10as described herein, this process can reduce manufacturing costs.

The method includes extruding the housing28formed of aluminum. In other words, the housing28is formed of extruded aluminum. By utilizing aluminum for the housing28, the mass of the housing28can be reduced. The extruded housing28is formed defining the first chamber38and the first passage40spaced from each other. The first chamber38and the first passage40are formed in the aluminum housing28in the non-concentric configuration.

Furthermore, extruding the housing28formed of aluminum can be further defined as extruding the housing28to further define the second chamber66and the second passage68. Therefore, the extruded housing28can be formed defining the second chamber66and the second passage68spaced from each other and each spaced from the first chamber38and the first passage40. The first and second chambers38,66and the first and second passages40,68are formed in the aluminum housing28substantially parallel to each other in a non-concentric orientation. Having the housing28formed of extruded aluminum with the first and second chambers38,66and the first and second passages40,68being substantially parallel to each other allows the housing28to be formed in a cost effective way. For example, drilling, milling, etc., of the housing28is minimized with this arrangement of chambers38,66and passages40,68. It is to be appreciated that the extruded aluminum is cut to create the desired length of the housing28. Furthermore, forming the housing28of aluminum can improve heat dispersion.

The method further includes milling the first distal end30of the housing28to partially form the first inlet42that fluidly connects the first chamber38and the first passage40. When one of the caps102is secured to the first distal end30of the housing28, that cap102partially forms the first inlet42(seeFIG. 9). Therefore, the housing28and the cap102cooperate to define the first inlet42.

The method can further include milling the second distal end32of the housing28to partially form the first outlet62that fluidly connects the first chamber38and the first passage40. When another one of the caps102is secured to the second distal end32of the housing28, that cap102partially forms the first outlet62(seeFIG. 9). Therefore, the housing28and the cap102cooperate to define the first outlet62.

The method can also include milling the first distal end30of the housing28to partially form the second outlet96that fluidly connects the first chamber38and the second passage68. As discussed above, the first inlet42and the second outlet96are spaced from each other along the first distal end30of the housing28. When one of the caps102is secured to the first distal end30of the housing28, that cap102partially forms the second outlet96(seeFIG. 10). Therefore, the housing28and the cap102cooperate to define the second outlet96.

The method can also include milling the second distal end32of the housing28to partially form the second inlet72that fluidly connects the first chamber38and the second passage68. As discussed above, the first outlet62and the second inlet72spaced from each other along the second distal end32of the housing28. When one of the caps102is secured to the second distal end32of the housing28, that cap102partially forms the second inlet72(seeFIG. 10). Therefore, the housing28and the cap102cooperate to define the second inlet72.

The caps102can be cold formed, machined or formed by any other suitable methods. Furthermore, the caps102can be attached or secured to the housing28by any suitable methods. For example, the caps102can be press fit, friction fit, interference fit, adhered, welded, crimped, etc., to the housing28. Therefore, the method can include attaching the plurality of caps102to the housing28. As such, the caps102close or plug the ends104,106,112,114of the first and second chambers38,66and the ends108,110,116,118of first and second passages40,68.

The method can further include drilling the housing28between the first passage40and the second chamber66to define the first pathway90that fluidly connects the first passage40and the second chamber66. Generally, the first pathway90is disposed between the first inlet42and the first outlet62. The first pathway90can be drilled in any suitable orientation.FIGS. 7 and 15illustrate the first pathway90disposed at an angle, or transverse, relative to the first passage40due to the available space to insert a tool into one of the first passage40and the second chamber66to drill the first pathway90.FIG. 17illustrates another alternative of the orientation of the first pathway90in which the first pathway90is disposed substantially perpendicular to the first passage40.

The method can further include drilling the housing28between the second passage68and the second chamber66to define the second pathway100that fluidly connects the second passage68and the second chamber66. Generally, the second pathway100is disposed between the second inlet72and the second outlet96. The second pathway100can be drilled in any suitable orientation.FIGS. 8 and 16illustrate the second pathway100disposed at an angle, or transverse, relative to the second passage68due to the available space to insert a tool into one of the second passage68and the second chamber66to drill the second pathway100.FIG. 18illustrates another alternative of the orientation of the second pathway100in which the second pathway100is disposed substantially perpendicular to the second passage68.

Once the pathways90,100and passages40,68are formed, various components can be positioned, disposed or inserted in the housing28. For example, the piston46, the member76, the first and second restrictor valves58,92, the first and second one-way valves64,98and optionally, the first and second ER valves124,126can be positioned, disposed or inserted in the housing28, some of which are discussed below.

The method also includes disposing the piston46in the first chamber38. Generally, disposing the piston46in the first chamber38can occur after milling the first and second distal ends30,32of the housing28to partially form the first inlet42, the first outlet62, the second inlet72and the second outlet96. Also, disposing the piston46in the first chamber38can occur after drilling the housing28to define the first pathway90and the second pathway100. It is to be appreciated that the piston46can be disposed in the first chamber38in any suitable order. The piston46is disposed in the first chamber38before securing the cap102(i.e., the cap102that covers the second end112of the first chamber38) to the second distal end32of the housing28. It is to be appreciated that the rod52can be inserted in the first chamber38with the piston46.

The method further includes inserting the first restrictor valve58in the first passage40. In certain embodiments, the first restrictor valve58is inserted in the first passage40proximal to the first inlet42. The first restrictor valve58can be press fit, interference fit, etc., into the first passage40to position the first restrictor valve58in the desired position in the first passage40. Optionally, the housing28can present a first shoulder inside the first passage40, and the first restrictor valve58can be inserted into the first passage40until the first restrictor valve58abuts the first shoulder in the first passage40to position the first restrictor valve58in the desired position. When utilizing the first shoulder in the first passage40, the first shoulder can be formed in the first passage40by milling, drilling or any other suitable method.

The method can further include inserting the first one-way valve64in the first passage40. In certain embodiments, the first one-way valve64is inserted in the first passage40proximal to the first outlet62. The first one-way valve64can be press fit, interference fit, etc., into the first passage40to position the first one-way valve64in the desired position in the first passage40. Optionally, the housing28can present a second shoulder inside the first passage40, and the first one-way valve64can be inserted into the first passage40until the first one-way valve64abuts the second shoulder in the first passage40to position the first one-way valve64in the desired position. When utilizing the second shoulder in the first passage40, the second shoulder can be formed in the first passage40by milling, drilling or any other suitable method.

The method can also include inserting the second restrictor valve92in the second passage68. In certain embodiments, the second restrictor valve92is inserted in the second passage68proximal to the second inlet72. The second restrictor valve92can be press fit, interference fit, etc., into the second passage68to position the second restrictor valve92in the desired position in the second passage68. Optionally, the housing28can present a first shoulder inside the second passage68, and the second restrictor valve92can be inserted into the second passage68until the second restrictor valve92abuts the first shoulder in the second passage68to position the second restrictor valve92in the desired position. When utilizing the first shoulder in the second passage68, the first shoulder can be formed in the second passage68by milling, drilling or any other suitable method.

The method can further include inserting the second one-way valve98in the second passage68. In certain embodiments, the second one-way valve98is inserted in the second passage68proximal to the second outlet96. The second one-way valve98can be press fit, interference fit, etc., into the second passage68to position the second one-way valve98in the desired position in the second passage68. Optionally, the housing28can present a second shoulder inside the second passage68, and the second one-way valve98can be inserted into the second passage68until the second one-way valve98abuts the second shoulder in the second passage68to position the second one-way valve98in the desired position. When utilizing the second shoulder in the second passage68, the second shoulder can be formed in the second passage68by milling, drilling or any other suitable method.

The first and second restrictor valves58,92and the first and second one-way valves64,98can be inserted in the appropriate passage40,68in any desired order. Once the first restrictor valve58and the first one-way valve64are inserted in the first passage40, the ends108,116of the first passage40can be closed with the caps102. Similarly, once the second restrictor valve92and the second one-way valve98are inserted in the second passage68, the ends110,118of the second passage68can be closed with the caps102.

The method can also include inserting the member76in the second chamber66. Once the member76is inserted in the second chamber66, the first and second ends106,114of the second chamber66can be closed with the caps102. Furthermore, once the various components are disposed in the housing28and various caps102attached to the housing28, the liquid44is injected into the housing28and the gaseous fluid74is injected into the second chamber66.

When the damper assembly10utilizes the first and second ER valves124,126, the method can also include inserting the first ER valve124in the first passage40and inserting the second ER valve126in the second passage68. The first ER valve124is inserted into the first passage40before one of the first restrictor valve58or the first one-way valve64. Similarly, the second ER valve126is inserted into the second passage68before one of the second restrictor valve92or the second one-way valve98. Additionally, when the damper assembly10utilizes the actuator144, the method can include coupling the actuator144to the housing28. It is to be appreciated that the method can include other features described herein.

While the best modes and other embodiments for carrying out the disclosure have been described in detail, those familiar with the art to which this disclosure relates will recognize various alternative designs and embodiments for practicing the disclosure within the scope of the appended claims. Furthermore, the embodiments shown in the drawings or the characteristics of various embodiments mentioned in the present description are not necessarily to be understood as embodiments independent of each other. Rather, it is possible that each of the characteristics described in one of the examples of an embodiment can be combined with one or a plurality of other desired characteristics from other embodiments, resulting in other embodiments not described in words or by reference to the drawings. Accordingly, such other embodiments fall within the framework of the scope of the appended claims.