초록 ▼

A gas spring for a hatch type door is disclosed, which comprises a cylinder, a piston received in the cylinder to divide the same into first and second chambers, a piston rod connected to the piston, a first device for providing a passage between the first and second chambers only when the piston mo

A gas spring for a hatch type door is disclosed, which comprises a cylinder, a piston received in the cylinder to divide the same into first and second chambers, a piston rod connected to the piston, a first device for providing a passage between the first and second chambers only when the piston moves in a direction to contract the second chamber, a second device for providing a passage between these chambers only when the piston rod is pushed against the piston by a force greater than a predetermined degree, and a third device for providing a passage between these chambers only when the piston is positioned within a predetermined area in the cylinder.

대표청구항 ▼

A gas spring comprising: a cylinder; a free piston axially slidably and sealingly received in said cylinder to divide the interior of said cylinder into a gas chamber and a working liquid chamber; a piston axially slidably received in said working liquid chamber to divide the same into first and sec

A gas spring comprising: a cylinder; a free piston axially slidably and sealingly received in said cylinder to divide the interior of said cylinder into a gas chamber and a working liquid chamber; a piston axially slidably received in said working liquid chamber to divide the same into first and second working liquid chamber sections, the first section being located in the vicinity of said gas chamber; a piston rod connected at its one end to said piston and extending therefrom through said second working liquid chamber section to project axially outwardly from said cylinder; a first valve means for providing a passage between said first and second working liquid chmaber sections only when said piston moves in a direction to contract said second working liquid chamber section; a second valve means for providing a passage between said first and second working liquid chamber sections only when said piston moves in a direction to contract said first working liquid chamber section; and a third means for providing an additional passage when said piston is positioned in a predetermined area near said gas chamber, wherein said second means is constructed to form the passage between said first and second working liquid chamber sections when said piston rod is pushed toward said gas chamber to provide a displacement thereof relative to said piston.