Flush toilet

Abstract

A flush toilet includes a bowl and a drain trap pipe line. The bowl includes a waste receiving surface for human waste, a rim above the waste receiving surface, a shelf between the waste receiving surface and the rim, and a standing water part such that a standing water surface forms inside the standing water part. The drain trap pipe line is connected to a lower part of the bowl and configured to discharge human waste. The rim includes an inner circumferential surface, and one rim discharge port configured to generate a swirling flow of flush water by discharging the flush water along the inner circumferential surface. The shelf extends along an entire circumference of the bowl. An outer circumference edge of the shelf has a minimum curvature radius in a first region when viewed in plan. A width of the shelf has a minimum in the first region.

Description

TECHNICAL FIELD

[0001] Aspects of the present invention relate to a flush toilet, and particularly to a flush toilet that discharges human waste by flushing with flush water.BACKGROUND

[0002] A known flush toilet such as an example described in Patent Literature 1 includes a waste receiving surface that receives human waste, a rim formed above the waste receiving surface, a shelf formed between the waste receiving surface and the rim, and one rim discharge port that is located at the rim and generates a swirling flow of flush water by discharging the flush water along the inner circumferential surface of the rim. In such a flush toilet, the width of the shelf in the front region of the bowl is reduced because the flush water swirling around on the shelf in the front region does not easily flow downward onto the waste receiving surface due to the small curvature radius of the bowl in the front region. As a result, the flush water swirling around on the shelf in the front region of the bowl easily flows downward, and the flushing performance of the bowl is improved.PRIOR ARTPatent Literature

[0003] [Patent Literature 1] Japanese Patent Application Laid-Open No. 2002-294842SUMMARY OF THE INVENTION

[0004] However, in the flush toilet described in Patent Literature 1 described above, the width of the shelf is reduced in the front region in which the curvature radius of the bowl is small, but the shelf is not configured so that the width of the shelf changes according to the curvature radius of the outer circumference edge of the shelf. Therefore, there is a problem in that, for example, at a part at which the curvature radius of the bowl is large and the curvature radius of the outer circumference edge of the shelf is small, the flush water swirling around on the shelf still does not easily flow downward onto the waste receiving surface; and the human waste that is adhered to the waste receiving surface remains without being washed away.

[0005] As a result of diligent research, the present inventors found that in order to solve the problem of the human waste remaining adhered to the waste receiving surface without being washed away, it is important to configure the shelf so that the width of the shelf changes according to the curvature radius of the outer circumference edge of the shelf.

[0006] Therefore, the present invention is directed to solve the problem described above, and is directed to a flush toilet that can evenly wash the waste receiving surface by causing the flush water swirling around on the shelf to flow downward onto the waste receiving surface.

[0007] To achieve such an object, an aspect of the present invention is a flush toilet configured to discharge human waste by flushing with flush water, in which the flush toilet includes a bowl and a drain trap pipe line; the bowl includes a waste receiving surface configured to receive human waste, a rim located above the waste receiving surface, a shelf located between the waste receiving surface and the rim, and a standing water part that is located below the waste receiving surface and configured so that a standing water surface forms inside the standing water part; the drain trap pipe line is connected to a lower part of the bowl and configured to discharge human waste; the rim includes an inner circumferential surface, and one rim discharge port configured to generate a swirling flow of flush water by discharging the flush water along the inner circumferential surface of the rim; the shelf extends along an entire circumference of the bowl; an outer circumference edge of the shelf has a minimum curvature radius in a first region when viewed in plan; and a width of the shelf has a minimum in the first region.

[0008] According to the aspect of the present invention having such a configuration, the shelf extends along the entire circumference of the bowl; and the width of the shelf has a minimum in the first region in which the outer circumference edge of the shelf has a minimum curvature radius when viewed in plan; therefore, the flush water swirling around on the shelf can flow downward onto the waste receiving surface in the first region in which the flush water does not easily flow downward onto the waste receiving surface due to the effects of a centrifugal force; and the waste receiving surface can be evenly washed.

[0009] According to the aspect of the present invention, favorably, the rim discharge port is located at one of a left side or a right side of the bowl; the rim discharge port is configured to discharge the flush water frontward; and the width of the shelf at the one of the left side or the right side of the bowl, at which the rim discharge port is located, is greater than the width of the shelf at the other of the left side or the right side.

[0010] In the aspect of the present invention having such a configuration, the rim discharge port is located at one of the left side or the right side of the bowl and is configured to discharge the flush water frontward; and the width of the shelf at the one of the left side or the right side of the bowl, at which the rim discharge port is located, is greater than the width of the shelf at the other of the left side or the right side; therefore, the flush water can swirl around on the shelf while being prevented from undesirably falling onto the waste receiving surface directly after being discharged from the rim discharge port.

[0011] According to the aspect of the present invention, favorably, the outer circumference edge of the shelf has a maximum curvature radius in a second region when viewed in plan; and the width of the shelf is substantially constant in the second region.

[0012] In the aspect of the present invention having such a configuration, the width of the shelf in substantially constant in the second region in which the outer circumference edge of the shelf has a maximum curvature radius when viewed in plan; therefore, the flush water can be prevented from undesirably falling onto the waste receiving surface in the second region, and can swirl around on the shelf.

[0013] According to the aspect of the present invention, favorably, the width of the shelf gradually decreases from the second region toward the first region in a third region between the first region and the second region.

[0014] In the aspect of the present invention having such a configuration, the width of the shelf gradually decreases from the second region toward the first region in the third region between the first region and the second region; therefore, in the third region, the waste receiving surface can be evenly washed while adjusting the amount of the flush water swirling around on the shelf and the amount of the flush water flowing downward onto the waste receiving surface.

[0015] According to the aspect of the present invention, favorably, the first region is located at a front side of the bowl; and the second region is located at the left side of the bowl and at the right side of the bowl.

[0016] In the aspect of the present invention having such a configuration, the first region, in which the outer circumference edge of the shelf has a minimum curvature radius when viewed in plan, is located at the front side of the bowl; and the second region, in which the outer circumference edge of the shelf has a maximum curvature radius when viewed in plan, is located at the left side of the bowl and at the right side of the bowl; therefore, in the first region at the front side of the bowl, the flush water swirling around on the shelf can flow downward onto the waste receiving surface to evenly wash the waste receiving surface.

[0017] According to the aspect of the present invention, favorably, the width of the shelf at a back side of the bowl is greater than the width of the shelf in the first region and less than the width of the shelf in the second region.

[0018] In the aspect of the present invention having such a configuration, the width of the shelf at the back side of the bowl is greater than the width of the shelf in the first region and less than the width of the shelf in the second region; therefore, the flush water that flows downward onto the waste receiving surface at the back side of the bowl can be increased, and the back side of the bowl to which human waste easily adheres can be washed.

[0019] According to flush toilets of aspects of the present invention, flush water swirling around on the shelf can be caused to flow downward onto the waste receiving surface to evenly wash the waste receiving surface.BRIEF DESCRIPTION OF THE DRAWINGS

[0020] FIG. 1 is a plan view of a flush toilet according to an embodiment of the present invention;

[0021] FIG. 2 is a cross-sectional view along line II-II of FIG. 1;

[0022] FIG. 3 is a cross-sectional view along line III-III of FIG. 2;

[0023] FIG. 4A is a cross-sectional view along line IVA-IVA of FIG. 3;

[0024] FIG. 4B is a cross-sectional view along line IVB-IVB of FIG. 3;

[0025] FIG. 4C is a cross-sectional view along line IVC-IVC of FIG. 3;

[0026] FIG. 4D is a cross-sectional view along line IVD-IVD of FIG. 3;

[0027] FIG. 4E is a cross-sectional view along line IVE-IVE of FIG. 3;

[0028] FIG. 4F is a cross-sectional view along line IVF-IVF of FIG. 3;

[0029] FIG. 4G is a cross-sectional view along line IVG-IVG of FIG. 3; and

[0030] FIG. 5 is a plan view showing a flow of flush water in the flush toilet according to the embodiment of the present invention.DETAILED DESCRIPTION

[0031] A flush toilet according to an embodiment (hereinbelow, referred to as the present embodiment) of the present invention will now be described with reference to the drawings.

[0032] First, the overall structure of the flush toilet according to the present embodiment will be described with reference to FIGS. 1 and 2.

[0033] FIG. 1 is a plan view of the flush toilet according to the embodiment of the present invention; and FIG. 2 is a cross-sectional view along line II-II of FIG. 1.

[0034] As shown in FIGS. 1 and 2, the flush toilet 1 according to the present embodiment is a so-called siphon-jet toilet in which a siphon action is generated by a jet discharge filling the interior of a drain trap pipe line with water. The flush toilet 1 includes a ceramic toilet main body 2, a toilet seat and a toilet lid (not illustrated) located at the upper surface of the toilet main body 2, and a water storage tank (not illustrated) that is located at the upper back part of the toilet main body 2 and stores flush water to be used to flush the toilet.

[0035] Flush toilets of embodiments of the present invention are not limited to a siphon-jet flush toilet, and may be a siphon flush toilet that generates a siphon action with rim discharge, or a washdown flush toilet that pushes human waste with a flow action generated by the head of the flush water inside the bowl.

[0036] The flush toilet 1 includes the ceramic toilet main body 2; and the toilet main body 2 includes a bowl-shaped bowl 6, a drain trap pipe line 8 that is connected to the lower part of the bowl 6 and discharges human waste, a rim discharge port 10 that performs a rim discharge, a rim water conduit 12 that supplies flush water to the rim discharge port 10, a jet discharge port 14 that performs a jet discharge, and a jet water conduit 16 that supplies flush water to the jet discharge port 14.

[0037] The bowl 6 includes a waste receiving surface 18 that receives human waste, a rim 20 that is formed above the bowl 6 and includes an inner circumferential surface 20a at the inner side of the rim 20, a shelf 22 formed between the waste receiving surface 18 and the rim 20, and a standing water part 24 formed below the waste receiving surface 18 and configured so that a standing water surface WL forms inside the standing water part 24.

[0038] The drain trap pipe line 8 includes an inlet 8a, an ascending pipe line 8b extending upward from the inlet 8a, a descending pipe line 8c extending downward from the ascending pipe line 8b, and a top part 8d that is positioned between the descending pipe line 8c and the ascending pipe line 8b and regulates the water level of the standing water surface WL.

[0039] The lower end of the descending pipe line8c of the drain trap pipe line 8 is connected to a drain pipe (not illustrated) via a drain socket (not illustrated).

[0040] One rim discharge port 10 is located in a back region at the left side of the bowl 6 and is configured to discharge flush water frontward. The flush water that is discharged from the rim discharge port 10 swirls around the inner circumferential surface 20a of the rim 20 and the shelf 22 while flowing downward onto the waste receiving surface 18; and the waste receiving surface 18 is washed by the swirling flow.

[0041] The rim water conduit 12 is formed in a tapered configuration in which the flow channel cross section gradually decreases toward the rim discharge port 10. A service water pipe (not illustrated), which is a water supply source, is connected to the upstream side of the rim water conduit 12. Flush water from the service water pipe is supplied to the rim water conduit 12; and the water supply pressure of the service water pipe is utilized to discharge the flush water from the rim discharge port 10.

[0042] The water supply source that supplies the flush water to the rim discharge port 10 is not limited to the service water pipe of the present embodiment and may be a water storage tank, a pump, etc.

[0043] The jet discharge port 14 is formed at the bottom part of the bowl 6. The jet discharge port 14 is arranged to face the inlet 8a of the drain trap pipe line 8 and is directed toward the inlet 8a of the drain trap pipe line 8. The jet discharge port 14 discharges the flush water toward the inlet 8a of the drain trap pipe line 8 and generates a siphon action by promptly filling the interior of the drain trap pipe line 8 with water.

[0044] The jet water conduit 16 as an entirety is formed in a U-shape when viewed in plan. A water storage tank (not illustrated), which is a water supply source, is connected to the upstream side of the jet water conduit 16. The flush water from the water storage tank is supplied to the jet water conduit 16; and the flush water is discharged from the jet discharge port 14 by the head pressure of the flush water stored inside the water storage tank.

[0045] The water supply source that supplies the flush water to the jet discharge port 14 is not limited to the water storage tank of the present embodiment, and may be a service water pipe, a pump, etc.

[0046] In the flush toilet 1 of the present embodiment, the flush water amount used in the full flush is 4.8 liters; and the flush water amount used in the light flush is 3.8 liters. The flush water amount that is discharged from the rim discharge port 10 is 2.3 liters; and the instantaneous flow rate of the flush water discharged from the rim discharge port 10 is 10 to 20 L / min.

[0047] The shape of the bowl 6 of the flush toilet 1 according to the present embodiment will now be described in detail with reference to FIG. 3 and FIGS. 4A to 4G.

[0048] The figures herein are not necessarily drawn to scale, and do not implicitly limit dimensions or proportions of possible features according to various embodiments of the present invention.

[0049] FIG. 3 is a cross-sectional view along line III-III of FIG. 2; and FIGS. 4A to 4G are cross-sectional views viewed along lines IVA-IVA to IVG-IVG of FIG. 3.

[0050] In FIG. 3, regions formed by bisecting the interior of the bowl in the lateral direction as viewed from the front side of the toilet main body by a center line CL1 extending in the longitudinal direction of the toilet main body when viewed in plan are respectively referred to as the left side and right side of the bowl. Also, regions formed by bisecting the interior of the bowl in the longitudinal direction by a center line CL2 extending in the lateral direction of the toilet main body when viewed in plan are respectively referred to as the front side and back side of the bowl. FIGS. 4A to 4G are cross sections perpendicular to the flow direction of the flush water swirling around on the shelf.

[0051] “Longitudinal” means “frontward and / or backward”, and “lateral” means “leftward and / or rightward”. “Above”, “below”, “left”, “right”, “front”, “back”, and “behind” each indicate a relative position or action along one respective axis, without implying limitations along other axes. That is, “above” is not implicitly restricted to “directly above”, “behind” is not implicitly restricted to “directly behind”, etc.

[0052] As shown in FIG. 3, the shelf 22 extends along the entire circumference of the bowl 6. The shelf 22 is inclined closer to horizontal than the waste receiving surface 18, and is configured so that flush water can be swirled around on the shelf 22. The shelf 22 is slightly inclined downward toward the interior of the bowl 6; and the incline angle of the incline of the shelf 22 downward toward the interior of the bowl 6 is substantially constant around the entire circumference of the bowl 6. Although the shelf 22 is inclined downward toward the interior of the bowl 6 according to the present embodiment, the shelf 22 may be horizontal, or the shelf 22 may be further inclined as long as the flush water can swirl around on the shelf 22. A portion of the flush water discharged from the rim discharge port 10 flows downward onto the waste receiving surface; and the remainder of the flush water swirls around on the shelf 22.

[0053] As shown in FIGS. 4A to 4G, the shelf 22 includes an outer circumference edge 22a positioned at the outermost side of the shelf 22, an inner circumference edge 22b positioned at the innermost side of the shelf 22, and a substantially flat shelf surface 22c positioned between the outer circumference edge 22a and the inner circumference edge 22b. The inner circumferential surface 20a of the rim 20 extends vertically upward from the outer circumference edge 22a of the shelf 22 and then overhangs toward the interior of the bowl 6.

[0054] Herein, the width of the shelf 22 is a distance along a line segment perpendicular to the outer circumference edge 22a of the shelf 22 when viewed in plan.

[0055] As shown in FIG. 3, the outer circumference edge 22a of the shelf 22 includes a first region A1 at the front side of the bowl 6 in which the outer circumference edge 22a has a minimum first curvature radius R1. The outer circumference edge 22a of the shelf 22 also includes second regions A2 at the left side and right side of the bowl 6 in which the outer circumference edge 22a has a maximum second curvature radius R2. The outer circumference edge 22a of the shelf 22 also includes a third region A3 between the first region A1 and the second region A2 in which the outer circumference edge 22a has a third curvature radius R3 that is greater than the first curvature radius R1 and less than the second curvature radius R2 (R1<R3<R2). The outer circumference edge 22a of the shelf 22 also includes a fourth region A4 at the back side of the bowl 6 in which the outer circumference edge 22a has a fourth curvature radius R4 that is greater than the first curvature radius R1 and less than the second curvature radius R2 (R1<R4<R2).

[0056] As shown in FIGS. 3 and 4D, the width of the shelf 22 has a minimum first width W1 in the first region A1 in which the outer circumference edge 22a of the shelf 22 has the minimum first curvature radius R1 when viewed in plan. As a result, in the first region A1, the flush water that swirls around on the shelf 22 can flow downward onto the waste receiving surface 18 even when affected by a centrifugal force.

[0057] As shown in FIGS. 3, 4A, and 4B, in the second region A2 at the left side in which the outer circumference edge 22a of the shelf 22 has the maximum second curvature radius R2 when viewed in plan, the width of the shelf 22 has a substantially constant second width W2 from the upstream side to the downstream side. As a result, in the second region A2 at the left side, the flush water that is discharged from the rim discharge port 10 can swirl around on the shelf 22 while being prevented from undesirably falling onto the waste receiving surface 18.

[0058] As shown in FIGS. 3 and 4F, in the second region A2 at the right side in which the outer circumference edge 22a of the shelf 22 has the maximum second curvature radius R2 when viewed in plan, the width of the shelf 22 has a substantially constant third width W3 from the upstream side to the downstream side. As a result, in the second region A2 at the right side, the flush water that has passed through the first region A1 can swirl around on the shelf 22 while being prevented from undesirably falling onto the waste receiving surface 18. As a result, the flush water that has passed through the second region A2 at the right side can reach the back side of the bowl 6 as much as possible.

[0059] As shown in FIGS. 3, 4A, and 4F, the second width W2 of the shelf 22 at the left side of the bowl 6, which is the side among the left side and right side of the bowl 6 at which the rim discharge port 10 is located, is greater than the third width W3 of the shelf 22 at the right side of the bowl 6, which is the side at which the rim discharge port 10 is not located. As a result, the flush water can swirl around on the shelf 22 while being prevented from undesirably falling onto the waste receiving surface 18 directly after being discharged from the rim discharge port 10. As shown in FIG. 4A, the second width W2 of the shelf 22 at the left side of the bowl 6 is set to be about 3 or more times the horizontal width of the rim discharge port 10.

[0060] As shown in FIGS. 3 and 4C, in the third region A3 at the left side between the first region A1 and the second region A2, a fourth width W4 of the shelf 22 has a substantially constant width from the second region A2 and then gradually decreases toward the first region A1. As a result, in the third region A3 at the left side, the flush water that swirls around on the shelf 22 can be gradually reduced, and the flush water that flows downward onto the waste receiving surface 18 can be gradually increased. As shown in FIGS. 3 and 4E, in the third region A3 at the right side between the first region A1 and the second region A2, a fifth width W5 of the shelf 22 gradually increases from the first region A1 and then is substantially constant toward the second region A2. As a result, in the third region A3 at the right side, the flush water that flows downward onto the waste receiving surface 18 can be gradually reduced, and the flush water that swirls around on the shelf 22 can be gradually increased.

[0061] As shown in FIG. 3, in a region B that spreads in a flared shape between a virtual line L1 and a virtual line L2 over central angles α (each being about 45°) from a center O of the bowl 6, the fourth and fifth widths W4 and W5 of the shelf 22 gradually decrease from the back side toward the front side. As a result, the flush water that flows downward onto the waste receiving surface 18 at the front side of the bowl 6 gradually increases.

[0062] As shown in FIGS. 3 and 4G, a sixth width W6 of the shelf 22 in the fourth region A4 is greater than the first width W1 of the shelf 22 in the first region and less than the second and third widths W2 and W3 of the shelf 22 in the second regions A2 at the left and right sides. As a result, the flush water that flows downward onto the waste receiving surface 18 at the back side of the bowl 6 can be increased to wash the back side of the bowl 6 to which human waste easily adheres. In the fourth region A4, the sixth width W6 of the shelf 22 gradually decreases along the direction in which the flush water swirls.

[0063] As shown in FIG. 3, the waste receiving surface 18 (the waste receiving surface 18 positioned higher than the standing water part 24) is formed to have a downward concave shape along the entire circumference of the bowl 6 when viewed in side-view (see FIG. 2). As a result, the flush water that flows down from the shelf 22 moves onto the waste receiving surface 18 and swirls around on the waste receiving surface 18. As a result, the waste receiving surface 18 is sufficiently washed. The width of the waste receiving surface 18 at the front side of the bowl 6 is greater than the width of the waste receiving surface 18 at the back side of the bowl 6 when viewed in plan (see FIG. 3).

[0064] A flow of flush water swirling through the bowl 6 of the flush toilet according to the present embodiment will now be described with reference to FIG. 5.

[0065] FIG. 5 is a plan view showing the flow of the flush water in the flush toilet according to the embodiment of the present invention.

[0066] F1 to F6 in FIG. 5 illustrate flows of the flush water.

[0067] First, as shown in FIG. 5, the flush water that is supplied from the rim water conduit 12 is discharged frontward from the rim discharge port 10. In the second region A2 at the left side at which the outer circumference edge 22a of the shelf 22 has the maximum second curvature radius R2, the second width W2 of the shelf 22 is substantially constant, which causes the majority of the flush water to flow around on the shelf 22 (the flow F1 of the flush water).

[0068] Then, in the third region A3 at the left side, the fourth width W4 of the shelf 22 gradually decreases along the direction in which the flush water swirls, and so the flush water that flows downward onto the waste receiving surface 18 gradually increases, and the remaining flush water flows around on the shelf 22 (the flow F2 of the flush water).

[0069] Continuing, the first width W1 of the shelf 22 has a minimum in the first region A1 in which the outer circumference edge 22a of the shelf 22 has the minimum first curvature radius R1, and so the flush water that flows downward onto the waste receiving surface 18 increases further, and the remaining flush water flows around on the shelf 22 (the flow F3 of the flush water). The waste receiving surface 18 at the front side of the bowl 6 can be sufficiently washed thereby.

[0070] Then, in the third region A3 at the right side, the fifth width W5 of the shelf 22 gradually increases along the direction in which the flush water swirls, and so the flush water that flows downward onto the waste receiving surface 18 gradually decreases, and the remaining flush water flows around on the shelf 22 (the flow F4 of the flush water).

[0071] Continuing, the third width W3 of the shelf 22 is substantially constant in the second region A2 at the right side in which the outer circumference edge 22a of the shelf 22 has the maximum second curvature radius R2, and so the majority of the flush water flows around on the shelf 22 (the flow F5 of the flush water).

[0072] Then, the sixth width W6 of the shelf 22 is relatively small in the fourth region A4 of the back side of the bowl 6, and so the flush water that flows downward onto the waste receiving surface 18 increases, and the waste receiving surface 18 at the back side of the bowl 6 can be sufficiently washed (the flow F6 of the flush water).

[0073] Effects of the flush toilet 1 according to the present embodiment above will now be described.

[0074] First, in the flush toilet 1 according to the present embodiment, the shelf 22 extends along the entire circumference of the bowl 6 and is formed so that the first width W1 of the shelf 22 has a minimum in the first region A1 in which the outer circumference edge 22a of the shelf 22 has the minimum first curvature radius R1 when viewed in plan; therefore, the flush water swirling around on the shelf 22 in the first region A1, in which the flush water does not easily flow downward onto the waste receiving surface 18 due to the effects of a centrifugal force, can flow downward onto the waste receiving surface 18 to evenly wash the waste receiving surface 18.

[0075] In the flush toilet 1 according to the present embodiment, the rim discharge port 10 is located at the left side (or the right side) of the bowl 6 and is configured to discharge the flush water frontward; and the second width W2 of the shelf 22 at the left side (or the right side) of the bowl 6 at which the rim discharge port 10 is located is greater than the third width W3 of the shelf 22 at the right side (or the left side); therefore, the flush water can swirl around on the shelf 22 while being prevented from undesirably falling onto the waste receiving surface 18 directly after being discharged from the rim discharge port 10.

[0076] In the flush toilet 1 according to the present embodiment, the second and third widths W2 and W3 of the shelf 22 are substantially constant in the second regions in which the outer circumference edge 22a of the shelf 22 has the maximum second curvature radius R2 when viewed in plan, and so the flush water in the second regions can swirl around on the shelf 22 while being prevented from undesirably falling onto the waste receiving surface 18.

[0077] In the flush toilet 1 according to the present embodiment, the fourth and fifth widths W4 and W5 of the shelf 22 gradually decrease from the second region A2 toward the first region A1 in the third region A3 between the first region A1 and the second region A2, and so the waste receiving surface 18 can be evenly washed while adjusting the amount of the flush water swirling around on the shelf 22 in the third region A3 and the amount of the flush water flowing downward onto the waste receiving surface 18.

[0078] In the flush toilet 1 according to the present embodiment, the first region A1, in which the outer circumference edge 22a of the shelf 22 has the minimum first curvature radius R1 when viewed in plan, is located at the front side of the bowl 6; and the second region A2, in which the outer circumference edge 22a of the shelf 22 has the maximum second curvature radius R2 when viewed in plan, is located at the left side and right side of the bowl 6; therefore, the flush water swirling around on the shelf 22 in the first region A1 of the front side of the bowl 6 can flow downward onto the waste receiving surface 18 to evenly wash the waste receiving surface 18.

[0079] In the flush toilet 1 according to the present embodiment, the sixth width W6 of the shelf 22 at the back side of the bowl 6 (the fourth region A4) is greater than the first width W1 of the shelf 22 in the first region A1 and less than the second and third widths W2 and W3 of the shelf 22 in the second regions A2; therefore, the flush water that flows downward onto the waste receiving surface 18 at the back side of the bowl 6 is increased to wash the back side of the bowl 6 to which human waste easily adheres.

[0080] Various changes and modifications are possible within the scope of the technical ideas described in the claims without limiting the embodiments of the present invention described above.

Claims

1. A flush toilet configured to discharge human waste by flushing with flush water, the flush toilet comprising:a bowl includinga waste receiving surface configured to receive human waste,a rim located above the waste receiving surface,a shelf located between the waste receiving surface and the rim, anda standing water part located below the waste receiving surface, the standing water part being configured so that a standing water surface forms inside the standing water part; anda drain trap pipe line connected to a lower part of the bowl, the drain trap pipe line being configured to discharge human waste, whereinthe rim includes an inner circumferential surface, and one rim discharge port configured to generate a swirling flow of flush water by discharging the flush water along the inner circumferential surface of the rim,the shelf extends along an entire circumference of the bowl,an outer circumference edge of the shelf has a minimum curvature radius in a first region when viewed in plan, anda width of the shelf has a minimum in the first region.

2. The flush toilet according to claim 1, whereinthe rim discharge port is located at one of a left side or a right side of the bowl,the rim discharge port is configured to discharge the flush water frontward, andthe width of the shelf at the one of the left side or the right side of the bowl is greater than the width of the shelf at the other of the left side or the right side of the bowl.

3. The flush toilet according to claim 2, whereinthe outer circumference edge of the shelf has a maximum curvature radius in a second region when viewed in plan, andthe width of the shelf is substantially constant in the second region.

4. The flush toilet according to claim 3, wherein the width of the shelf gradually decreases from the second region toward the first region in a third region between the first region and the second region.

5. The flush toilet according to claim 3, whereinthe first region is located at a front side of the bowl, andthe second region is located at the left side of the bowl and at the right side of the bowl.

6. The flush toilet according to claim 5, wherein the width of the shelf at a back side of the bowl is greater than the width of the shelf in the first region and less than the width of the shelf in the second region.

7. The flush toilet according to claim 4, whereinthe first region is located at a front side of the bowl, andthe second region is located at the left side of the bowl and at the right side of the bowl.

8. The flush toilet according to claim 7, wherein the width of the shelf at a back side of the bowl is greater than the width of the shelf in the first region and less than the width of the shelf in the second region.

Images