Gas spring and method of charging gas into the gas spring

A gas spring, comprising a rod member with a cylindrical piston, a cylinder main body fitted over the rod member, and an annular gas filling chamber filled with compressed gas and disposed between the rod member and the cylinder main body, wherein said gas spring is characterized by further comprising:

• a first sealing member fitted over the rod member at one end of the gas filling chamber, and a second sealing member fitted into the cylinder main body at the other end of the gas filling chamber;
• and
• a stopper member internally fitted and threadably engaged with the cylinder main body and slidably fitted over the rod member on the opposite side from the gas filling chamber in relation to the piston portion of the rod member;
• and by being configured such that the rod member is moved axially in relation to the cylinder main body while the first sealing member is prevented from reaching the threaded hole for the stopper member of the cylinder main body in a state in which the stopper member is not yet mounted, the gas filling chamber is filled with compressed gas through a rod insertion hole facing the second sealing member, the rod member is then moved back, and the stopper member is mounted.

A gas filling method for introducing compressed gas into a gas spring comprising a rod member with a cylindrical piston, a cylinder main body fitted over the rod member, an annular gas filling chamber filled with compressed gas and disposed between the rod member and the cylinder main body, a first sealing member fitted over the piston portion of the rod member at one end of the gas filling chamber, a second sealing member fitted into the cylinder main body at the other end of the gas filling chamber, a plurality of pin members disposed in an axially symmetrical fashion about the rod member, and a plurality of slots provided to the cylinder main body to allow individual mating with the plurality of pin members and to restrict the range of movement of the rod member in relation to the cylinder main body, wherein said gas filling method is characterized in that the gas spring is placed in a special gas filling implement in a state in which the pin members are not yet mounted;

• the cylinder main body is moved axially in relation to the rod member while the second sealing member is prevented from separating from the rod member;
• the gas filling chamber is filled with compressed gas through the gas filling implement and the slots;
• the cylinder main body is then moved back;
• and the pin members are locked in place.

A gas filling method for introducing compressed gas into a gas spring comprising a rod member with a cylindrical piston, a cylinder main body fitted over the rod member, an annular gas filling chamber filled with compressed gas and disposed between the rod member and the cylinder main body, a first sealing member fitted over the rod member at one end of the gas filling chamber, a second sealing member fitted into the cylinder main body at the other end of the gas filling chamber, and a stopper member internally fitted and threadably engaged with the cylinder main body and slidably fitted over the rod member on the opposite side from the gas filling chamber in relation to the piston portion of the rod member, wherein said gas filling method for a gas spring is characterized in that the gas spring is placed in a special gas filling implement in a state in which the stopper member is not yet mounted;

• the rod member is moved axially in relation to the cylinder main body while the first sealing member is prevented from reaching the threaded hole for the stopper member of the cylinder main body;
• the gas filling chamber is filled with compressed gas through the gas filling implement and a rod insertion hole facing the second sealing member;
• the rod member is then moved back;
• and the stopper member is mounted.