A flush toilet includes a bowl having a waste-receiving surface and a rim; on either the left or right side inside the front area of this bowl, a rim water passageway is formed and a rim spouting port is formed; the water passageway formed at the downstream side of this rim spouting port forms a flow path cross section with the inner circumferential surface of the rim, the shelf surface formed under this inner circumferential surface, and the overhang portion formed over the inner circumferential surface; the height dimension of the flow path cross section is set to increase with distance on the downstream side, and the width thereof is set to decrease with distance on the downstream side, so that from the rim spout port toward the downstream side, the cross sectional area of the flow path cross section is approximately constant.

A flush toilet includes a bowl having a waste-receiving surface and a rim; on either the left or right side inside the front area of this bowl, a rim water passageway is formed and a rim spouting port is formed; the water passageway formed at the downstream side of this rim spouting port forms a flow path cross section with the inner circumferential surface of the rim, the shelf surface formed under this inner circumferential surface, and the overhang portion formed over the inner circumferential surface; the height dimension of the flow path cross section is set to increase with distance on the downstream side, and the width thereof is set to decrease with distance on the downstream side, so that from the rim spout port toward the downstream side, the cross sectional area of the flow path cross section is approximately constant.

A flush toilet forms a bowl including a waste-receiving surface and a rim; a rim water passageway and rim spout port for spouting flush water into the bowl and forming a circulating flow are formed on the rim; this rim spout port downstream side flow path changes in curvature from small to large at curved portions formed at positions in the rim inner circumferential wall closest to the rim spout port in at least the right rear area inside the bowl and the front area inside the bowl, and these curved portions are formed by transition curves as seen in plan view.

A flush toilet forms a bowl including a waste-receiving surface and a rim; a rim water passageway and rim spout port for spouting flush water into the bowl and forming a circulating flow are formed on the rim; this rim spout port downstream side flow path changes in curvature from small to large at curved portions formed at positions in the rim inner circumferential wall closest to the rim spout port in at least the right rear area inside the bowl and the front area inside the bowl, and these curved portions are formed by transition curves as seen in plan view.

A siphonic flush toilet system and method of priming the same having a toilet bowl assembly comprising at least one jet flush valve assembly and at least one rim valve; and bowl having a rim and a jet defining at least one jet channel. The bowl has a closed jet pathway to maintain the jet channel in a primed state with fluid from the jet flush valve assembly to prevent air from entering the closed jet pathway. Flush valves may have back-flow preventer mechanisms and/or at least partly flexible valve covers, including specific valve cover structures. Flush activation assemblies may have a flush activation bar connected to the pivot rod and/or an adjustable flush connector located between the pivot rod and the flush activation bar. A kit providing one or more flush activation elements is included. The kit elements may be usable with the toilet systems and methods described.

A siphonic flush toilet system and method of priming the same having a toilet bowl assembly comprising at least one jet flush valve assembly and at least one rim valve; and bowl having a rim and a jet defining at least one jet channel. The bowl has a closed jet pathway to maintain the jet channel in a primed state with fluid from the jet flush valve assembly to prevent air from entering the closed jet pathway. Flush valves may have back-flow preventer mechanisms and/or at least partly flexible valve covers, including specific valve cover structures. Flush activation assemblies may have a flush activation bar connected to the pivot rod and/or an adjustable flush connector located between the pivot rod and the flush activation bar. A kit providing one or more flush activation elements is included. The kit elements may be usable with the toilet systems and methods described.

A flush toilet includes a toilet main body and a tank device for supplying flush water to the toilet main body, where the tank device includes a storage tank provided behind the toilet main body and above a floor surface, the storage tank includes a large tank section and a small tank section and has an asymmetrical shape in a front-back or left-right direction, the large tank section being a large-capacity side of the storage tank that is divided into two at a center in the left-right direction when seen in the front-back direction, the small tank section being a small-capacity side of the storage tank that is divided into two at the center in the left-right direction, and the storage tank or the toilet main body includes a deformation-preventing supporting member for preventing deformation of the storage tank by supporting the storage tank.

A flush toilet according to the embodiment includes a main water guide channel, a downstream-side water guide channel, and a convex part. Through the main water guide channel, flush water supplied from a water supply source flows. The downstream-side water guide channel on a downstream side of the main water guide channel spouts the flush water from a water spout port of the downstream-side water guide channel. The convex part is formed in the downstream-side water guide channel. The convex part includes a first guide part that guides upward the flush water flowing through the downstream-side water guide channel, and a second guide part on a downstream side of the first guide part which guides downward the flush water.

A flush toilet according to the embodiment includes a main water guide channel, a downstream-side water guide channel, and a convex part. Through the main water guide channel, flush water supplied from a water supply source flows. The downstream-side water guide channel on a downstream side of the main water guide channel spouts the flush water from a water spout port of the downstream-side water guide channel. The convex part is formed in the downstream-side water guide channel. The convex part includes a first guide part that guides upward the flush water flowing through the downstream-side water guide channel, and a second guide part on a downstream side of the first guide part which guides downward the flush water.

A flush toilet of the present invention includes a bowl including a waste receiving surface that receives waste, a rim formed on an upper part of the waste receiving surface and a well portion that is formed below the waste receiving surface and in which a pooled water surface is formed, one or more spouting ports that spout flush water along the rim, and a discharge conduit connected to a bottom portion of the bowl, the flush toilet including a configuration where a forward main flow F1 and a rearward main flow F2 of flush water spouted from the spouting ports circulate around a waste receiving surface 16 of a bowl 6 and flow, in the beginning of flushing start, into three or more regions of the pooled water surface divided into four regions S1, S2, S3 and S4.