Pistonless double-acting cylinder apparatus cross-reference to related applications

A pistonless double-acting cylinder apparatus, comprising:

• a piston rod member,
• a first cylinder member disposed on the piston rod member,
• a second cylinder member disposed on an end surface of the first cylinder member,
• a tie rod which connects the first cylinder member and the second cylinder member,
• nuts provided on both ends of the tie rod,
• a first sealing ring located between the first cylinder member and the second cylinder member, and
• a first cushion and a second cushion disposed on the piston rod member;
• wherein the piston rod member comprises:
• a piston rod left section,
• a first sealing gasket disposed on the piston rod left section,
• a piston rod middle section disposed on an end surface of the first sealing gasket,
• a second sealing gasket disposed on an end surface of the piston rod middle section, and
• a piston rod right section disposed on the second sealing gasket;
• wherein the first cylinder member comprises:
• a first outer end cover,
• a first dust-proof ring, a first guide ring, and a second sealing ring disposed within the first outer end cover,
• a first cylinder disposed on an end surface of the first outer end over,
• a third sealing ring disposed on an end surface of the first cylinder, and
• a first inner end cover disposed on the third sealing ring;
• wherein the first inner end cover comprises a first air hole;
• the second cylinder member comprises:
• a second outer end cover;
• a second dust-proof ring, a second guide ring, a fourth sealing ring disposed within the second outer end cover,
• a second cylinder disposed on an end surface of the second outer end cover,
• a fifth sealing ring disposed on an end surface of the second cylinder, and
• a second inner end cover disposed on the fifth sealing ring;
• wherein the second inner end cover comprises a second air hole.