Abstract: A pump consists of a valve box in which a valve chamber inlet and outlet are each provided with a valve, and reciprocating member in a cylinder that communicates with the valve chamber of the valve box to open the valves. A pressure action chamber is provided between the valve box and the cylinder and a pressure force member divides the pressure action chamber into a valve chamber side and a cylinder side. On the cylinder side of the pressure action chamber thus divided is an action medium that transmits to the pressure force member changes in the volume of the pressure action chamber produced by the action of the reciprocating member. A valve device consists of a concave valve seat and a number of fluid passages formed therein which open into the said concavity. Either the valve seat or the valve-piece is formed of, or covered with, a hard resilient material, or one is formed of the hard resilient material and the other is covered with a hard resilient material.

Abstract: A method of constructing shafts and continuous walls quickly and efficiently. The construction process consists of one step in which air and a ground hardener are injected through a jetting pipe element to form a column-shaped region of soil mixed with hardener; and another step in which a hardening inhibitor is injected into the soil-hardener mixture region by the jetting element, the shaft then being formed by excavating the portion of the ground that has not been hardened because of the presence of the inhibitor.

Abstract: A pump consists of a valve box in which a valve chamber inlet and outlet are each provided with a valve, and a reciprocating member in a cylinder that communicates with the valve chamber of the valve box to open the valves. A pressure action chamber is provided between the valve box and the cylinder and a pressure force member divides the pressure action chamber into a valve chamber side and a cylinder side. On the cylinder side of the pressure action chamber thus divided is an action medium that transmits to the pressure force member changes in the volume of the pressure action chamber produced by the action of the reciprocating member. A valve device consists of a concave valve seat and a number of fluid passages formed therein. Which open into the recess formed by the concave valve seat. Either the valve seat or the valve-piece is formed of, or covered with, a hard resilient material, or one is formed of the hard resilient material and the other is covered with a hard resilient material.