Eccentric rotary valve

An eccentric rotary valve comprising:

• a valve body tubular in shape and through which fluid can flow, the valve body having a fluid inlet and a fluid outlet;
• a valve shaft inserted in the valve body and having a center axis;
• a first valve element and a second valve element disposed on the valve shaft so as to be symmetrical to each other with respect to the center axis of the valve shaft, the first and second valve elements defining therebetween a through-passage configured to communicate with the fluid inlet and the fluid outlet of the valve body;
• a first valve body valve seat and a second valve body valve seat disposed in the valve body adjacent to the fluid inlet and the fluid outlet, respectively;
• and
• a first valve element valve seat and a second valve element valve seat disposed, respectively, on the first and second valve elements, and configured to abut, respectively, the first and second valve body valve seats,
• wherein each of the first and second valve elements has one of an elliptic spherical surface, an elliptic conical surface, and a completely spherical surface,
• wherein the first and second valve element valve seats and the first and second valve body valve seats are made of metal and forming a metal seal structure, with the first and second valve element valve seats being elliptic spherical surfaces, and the first and second valve body valve seats being elliptic conical surfaces,
• wherein the first and second valve element valve seats are continuously and steplessly connected, respectively, to the surfaces of the first and second valve elements, and
• wherein the first and second valve element valve seats and the first and second valve body valve seats have center axes, respectively, offset from the center axis of the valve shaft in a valve closing direction.

An eccentric rotary valve comprising:

• a valve body tubular in shape and through which fluid can flow, the valve body having a fluid inlet and a fluid outlet;
• a valve shaft inserted in the valve body and having a center axis;
• a first valve element and a second valve element disposed on the valve shaft so as to be symmetrical to each other with respect to the center axis of the valve shaft, the first and second valve elements defining therebetween a through-passage configured to communicate with the fluid inlet and the fluid outlet of the body;
• a first valve body valve seat and a second valve body valve seat disposed in the valve body adjacent to the fluid inlet and the fluid outlet, respectively;
• and
• a first valve element valve seat and a second valve element valve seat disposed, respectively, on the first and second valve elements, and configured to abut, respectively, the first and second valve body valve seats,
• wherein each of the first and second valve elements has a surface comprising an elliptic spherical surface,
• wherein the first and second valve element valve seats and the first and second valve body valve seats are elliptic conical surfaces made of metal and forming a metal seal structure,
• wherein the first and second valve element valve seats are continuously and steplessly connected, respectively, to the surfaces of the first and second valve elements, and
• wherein the first and second valve element valve seats and the first and second valve body valve seats have center axes, respectively, offset from the center axis of the valve shaft in a valve closing direction.