A cooking stove in which heat exchange between combustion gas and the bottom surface of a cooking container is sufficiently conducted and heat exchange efficiency is improved is provided. On a top plate, a plate that supports a cooking container is arranged concentrically with the burner head of the burner viewed from above. This plate is disc-shaped where an opening which is larger than the burner head is defined at the center. Moreover, eight protrusions having an angular cross section where slopes become gentler as they extend toward the outer circumferential side are spirally arranged around the opening viewed from above, and these protrusions are formed by press forming.
1. A cooking stove comprising:
a top plate of a body;
a burner;
a ring-shaped plate disposed on the top plate and around the burner; and
a plurality of protrusions having an angular cross section disposed on the ring-shaped plate spirally viewed from above, each of said protrusions being formed by two sides that are asymmetrically angular with respect to one another, each side having a single slope over substantially the entire height of said protrusion, wherein the slope of the side toward a center of the ring-shaped plate is gentler than the slope of the side toward an outer side of the ring-shaped plate,
wherein an entire apex of each protrusion lies on the same plane,
wherein combustion gas of the burner passes between the ring-shaped plate and a bottom surface of a cooking container which is supported by the ring-shaped plate to heat the cooking container.
2. A cooking stove according to claim 1 , wherein the protrusions are formed by press forming.
3. A cooking stove comprising:
a top plate of a body;
a burner;
a ring-shaped plate disposed on the top plate and around the burner; and
a plurality of protrusions having an angular cross section disposed on the ring-shaped plate spirally viewed from above, each of said protrusions being formed by two sides that are asymmetrically angular with respect to one another, each side having, a single slope over substantially the entire height of said protrusion, when viewed in a cross-section perpendicular to an extension direction of each said protrusion, wherein the slope of the side toward a center of the ring-shaped plate is gentler than the slope of the side toward an outer side of the ring-shaped plate,
wherein the ring-shaped plate and a bottom surface of a cooking container which is supported by the ring-shaped plate define a path for combustion gas to pass therethrough to heat the cooking container.
4. A cooking stove according to claim 2 , wherein the entirety of upper and lower extremities of said ring-shaped plate lie in planes that are parallel to one another.
5. A cooking stove according to claim 3 , wherein the protrusions are formed by press forming.
6. A cooking stove according to claim 5 , wherein the entirety of upper and lower extremities of said ring-shaped plate lie in planes that are parallel to one another.