Gas spring with filler valve

A gas spring comprising a cylinder defining at least in part a gas chamber, a rod with a head telescopically received in said cylinder and movable between extended and retracted positions and constructed and arranged to compress a gas within said chamber when moving from its extended position toward its retracted position, and a gas passage in communication with said cylinder and opening to the exterior of said cylinder, a filler valve having a housing exterior of the cylinder with a passage therethrough defining a valve cavity having an inlet and an outlet in communication therewith and a bleed passage in said housing in communication with said valve cavity and opening exteriorly of said housing, said housing constructed and arranged to be operably associated with the gas spring with said outlet in communication with said gas passage, a valve body having generally opposed ends constructed and arranged to be slidably received in said valve cavity for movement between a first position to prevent said outlet from communicating with said bleed passage and a second position disposed from said first position so that said outlet is in communication with said bleed passage to permit gas flow through said outlet and bleed passage to reduce the pressure of gas within the chamber and said valve body having a passage therethrough in communication with said inlet and said outlet of said housing, an inlet valve carried by said valve body for allowing gas to flow through said passage to charge the chamber with gas, said inlet valve being normally closed and opening in response to gas supplied to said valve cavity upstream of said valve through said inlet at a pressure substantially greater than the pressure of gas in the chamber and closing when the gas pressure in the chamber approaches such upstream pressure, and a seal associated with said housing and disposed between one end of said valve body and said outlet for sealing against said valve body when in said first position to prevent said outlet from communicating with said bleed passage, whereby said valve body has a first effective area communicating with said inlet in said housing and a second effective area communicating with said outlet in said housing, said second effective area being smaller than said first effective area and constructed and arranged so that when gas under pressure is applied to said valve cavity through said inlet upstream of said inlet valve and said valve body is in said first position, said valve body is moved toward its second position only when the force acting on said valve body in a direction tending to cause movement of said second body toward said valve position as a result of the pressure of said gas downstream of said inlet valve acting on said second effective area of said valve body exceeds the force acting on said valve body in a direction tending to cause movement of said valve body toward said first position due to the pressure of the gas applied upstream of said inlet valve acting on said first effective area of said valve body.