A liquid composite spring for vehicles includes: a core shaft; an outer sleeve arranged on an upper portion of the core shaft, the upper portion of the core shaft being located inside the outer sleeve while the lower portion of the core shaft being located outside the outer sleeve; an upper liquid chamber formed in an upper portion of the outer sleeve, a lower end of the upper liquid chamber being connected to a top of the core shaft; and a lower liquid chamber formed in a lower portion of outer sleeve, the lower liquid chamber and the upper liquid chamber being connected with each other through a metal-rubber main spring. At least one flow channel body is provided in the metal-rubber main spring, so that liquid in the upper liquid chamber and liquid in the lower liquid chamber are communicated with each other through the flow channel body.

A multi-axis isolator configured to isolate a payload from unwanted vibrations and shocks includes a housing, at least one pair of radial isolators in the housing, and an axial isolator in the housing. Each radial isolator includes an elastomer dome, a chamber at least partially defined by the elastomer dome, and a fluid in the chamber. The multi-axis isolator also includes a fluid track placing the chambers of the radial isolators in fluid communication with each other. The axial isolator includes an elastomer dome, a backpressure membrane, a primary chamber, a backpressure chamber, a fluid in the primary and backpressure chambers, a conduit placing the primary chamber in fluid communication with the backpressure chamber. The multi-axis isolator also includes a shaft configured to be connected to the payload. The pair of radial isolators and the axial isolator are coupled to the shaft.

Impact energy absorbing devices, in some embodiments, may be configured as a helmet having suspension elements employing “rate activated tethers” (RATs), a speed-sensitive flexible strapping material. The RATs are configured to suspend a helmet shell on the head of a wearer, so that impact to the helmet causes extension of the RATs. The RATs provide for: (1) steady force over long strokes, and (2) a stroke force that increases with increasing impact velocity. Standard impact testing of a helmeted headform shows that the RAT suspension decreases head accelerations by 50% relative to a standard suspension system. This decrease in head acceleration is expected to lead to a reduced likelihood of brain and head injury. Because the RATs absorb energy during tensile extension, they offer increases in energy absorption efficiency. These RAT suspensions can potentially replace or complement existing helmet pad and suspension systems in military, sports, and industrial safety-wear.

Impact energy absorbing devices, in some embodiments, may be configured as a helmet having suspension elements employing “rate activated tethers” (RATs), a speed-sensitive flexible strapping material. The RATs are configured to suspend a helmet shell on the head of a wearer, so that impact to the helmet causes extension of the RATs. The RATs provide for: (1) steady force over long strokes, and (2) a stroke force that increases with increasing impact velocity. Standard impact testing of a helmeted headform shows that the RAT suspension decreases head accelerations by 50% relative to a standard suspension system. This decrease in head acceleration is expected to lead to a reduced likelihood of brain and head injury. Because the RATs absorb energy during tensile extension, they offer increases in energy absorption efficiency. These RAT suspensions can potentially replace or complement existing helmet pad and suspension systems in military, sports, and industrial safety-wear.

A hydro-elastic damper comprising at least one elastic assembly comprising an elastic member between two strength members. The elastic assembly including a compression chamber. The hydro-elastic damper includes a damping assembly provided with an expansion chamber that is defined in a transverse direction by an end wall and by a piston. The compression chamber is hydraulically connected to the expansion chamber by three hydraulic connections comprising respectively: a duct; at least one first passage with an overpressure valve; and at least one second passage with a check valve.

A hydro-elastic damper comprising at least one elastic assembly comprising an elastic member between two strength members. The elastic assembly including a compression chamber. The hydro-elastic damper includes a damping assembly provided with an expansion chamber that is defined in a transverse direction by an end wall and by a piston. The compression chamber is hydraulically connected to the expansion chamber by three hydraulic connections comprising respectively: a duct; at least one first passage with an overpressure valve; and at least one second passage with a check valve.

A rotor system for a rotorcraft includes a rotor hub having a plurality of blade grips coupled thereto. Each blade grip has a rotor blade coupled thereto. A fairing is disposed at least partially around the rotor hub. Each of a plurality of lead-lag dampers is coupled to at least a respective one of the blade grips. Each lead-lag damper has a damper heat exchanger and a fluid pump operably associated therewith. A fairing heat exchanger is in fluid communication with the damper heat exchangers and the fluid pumps. Each lead-lag damper is configured to drive the respective fluid pump responsive to damping operations to pump a cooling fluid from the respective damper heat exchanger to the fairing heat exchanger.

A rotor system for a rotorcraft includes a rotor hub having a plurality of blade grips coupled thereto. Each blade grip has a rotor blade coupled thereto. A fairing is disposed at least partially around the rotor hub. Each of a plurality of lead-lag dampers is coupled to at least a respective one of the blade grips. Each lead-lag damper has a damper heat exchanger and a fluid pump operably associated therewith. A fairing heat exchanger is in fluid communication with the damper heat exchangers and the fluid pumps. Each lead-lag damper is configured to drive the respective fluid pump responsive to damping operations to pump a cooling fluid from the respective damper heat exchanger to the fairing heat exchanger.

A liquid composite spring for vehicles includes: a core shaft; an outer sleeve arranged on an upper portion of the core shaft, the upper portion of the core shaft being located inside the outer sleeve while the lower portion of the core shaft being located outside the outer sleeve; an upper liquid chamber formed in an upper portion of the outer sleeve, a lower end of the upper liquid chamber being connected to a top of the core shaft; and a lower liquid chamber formed in a lower portion of outer sleeve, the lower liquid chamber and the upper liquid chamber being connected with each other through a metal-rubber main spring. At least one flow channel body is provided in the metal-rubber main spring, so that liquid in the upper liquid chamber and liquid in the lower liquid chamber are communicated with each other through the flow channel body.

A method for sealing a liquid composite spring, includes the steps of: placing a sleeve-shaped outer wall around an upper portion of a core shaft, and forming an upper liquid chamber and a lower liquid chamber inside the outer wall; and arranging a sealing member at a bottom of the outer wall to seal the lower liquid chamber, wherein the sealing member is made of flexible material. The liquid composite spring is provided with the rigid outer wall and the flexible sealing member. The volume and shape of the lower liquid chamber can be changed through the flexible sealing member, so that the chamber is formed as a flexible chamber.