Flush toilet

Abstract

An object of the present invention is to provide a flush toilet capable of improving waste discharge performance even if a pooled water surface is formed larger than a conventional one.SOLUTION: The present invention has a bowl portion 6 comprising a waste receiving surface 14, a rim portion 16, and a pressure pot portion 18, a first spout port 20 disposed on the rim portion 16 on one side in the left-right direction of the bowl portion 6 for forming a circulating flow by spouting flush water along the inside perimeter surface 16a of the rim portion 16, and a second spout port 22 disposed on the rim portion 16 on the other side in the left-right direction of the bowl portion 6 for spouting flush water in the same direction as the circulating direction of flush water spouted from the first spout port 20 along the inside perimeter surface 16a of the rim portion 16. In the vicinity of the upstream side of the second spout port 22, a projecting portion 30 projecting toward the inside of the bowl portion 6 is provided on the upper portion of the 16a of the inner peripheral surface of the rim portion 16, and this projecting portion 30 has a bottom surface 16a configured to change the flow direction of flush water flowing on the 30d of the inner peripheral surface of the rim portion 16 to a downward direction.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a flush toilet, and more particularly to a flush toilet that expels waste using flush water supplied from a flush water source. [Background technology]

[0002] Conventionally, flush toilets have been known that include a waste receiving surface that receives waste, a rim portion formed above the waste receiving surface, a basin portion formed below the waste receiving surface and within which a water collection surface is formed, and first and second spouts that spout flush water along the inner surface of the rim portion to form a swirling flow. One such flush toilet, as shown in Patent Document 1, for example, is known in which a protrusion that protrudes toward the inside of the bowl is provided on the lower part of the inner circumferential surface of the rim near the second spout. In such a flush toilet, flush water discharged from the first spout swirls along the inner circumferential surface of the rim and hits the protrusion provided near the second spout. The flush water hits the side of the protrusion and changes direction of flow to the left. The flush water then flows down along the slope of the waste receiving surface toward the surface of the pool in the basin. This pushes waste toward the entrance of the drainage pipe and is discharged. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-200605 Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, in order to prevent waste from adhering to the waste receiving surface in a flush toilet, it is conceivable to reduce the area of ​​the waste receiving surface, which is the dry surface, and make the water collecting surface larger than before. However, in the flush toilet of Patent Document 1 mentioned above, if the water collecting surface is made larger than before, the force pushing the waste is dispersed and weakened, resulting in the problem that the waste remains without being expelled.

[0005] Therefore, the present invention has been made to solve the above-mentioned problems, and aims to provide a flush toilet that can improve waste discharge performance even if the water pooling surface is made larger than before. [Means for solving the problem]

[0006] In order to achieve the above-mentioned object, a flush toilet that discharges waste using flush water supplied from a flush water source is provided, the flush toilet having a bowl portion with a bowl-shaped waste receiving surface, a rim portion formed above the waste receiving surface and having an inner circumferential surface, and a basin portion formed below the waste receiving surface and having a water collection surface formed inside it, a first spout provided in the rim portion on one left-right side of the bowl portion and spouting flush water along the inner circumferential surface of the rim portion to form a swirling flow, a second spout provided in the rim portion on the other left-right side of the bowl portion and spouting flush water along the inner circumferential surface of the rim portion in the same direction as the swirling direction of the flush water spouted from the first spout, and a drainage pipe connected to the basin portion for discharging waste, and a protrusion that protrudes towards the inside of the bowl portion is provided on the upper part of the inner circumferential surface of the rim portion near the upstream side of the second spout and that has a bottom surface configured to change the flow direction of the flush water flowing along the inner circumferential surface of the rim portion downward. In the present invention configured in this way, a protrusion that protrudes toward the inside of the bowl is provided on the upper part of the inner surface of the rim near the upstream side of the second water outlet, and this protrusion has a bottom surface that is configured to change the flow direction of flush water flowing along the inner surface of the rim downward, so that the bottom surface of the protrusion can directly change the flow direction downward, strengthening the force of flush water flowing down toward the pooled water surface in the bowl. As a result, the force that pushes in waste can be strengthened, and waste discharge performance can be improved even if the pooled water surface is made larger than before.

[0007] In the present invention, the amount by which the innermost end of the protrusion protrudes inwardly into the bowl portion relative to the lower end of the inner circumferential surface of the rim portion is preferably set to increase toward the downstream side and then decrease thereafter. In the present invention configured in this manner, the amount by which the innermost end of the protrusion protrudes into the bowl portion relative to the lower end of the inner surface of the rim portion is preferably set to increase downstream and then decrease, thereby making it possible to make the protrusion less noticeable and allowing the cleaning water swirling around the inner surface of the rim portion to collide with the protrusion and flow down.

[0008] In the present invention, the maximum protruding amount of the protruding portion is preferably set to be the greatest on the inner circumferential surface of the rim portion in the rear region of the bowl portion. In the present invention configured in this manner, the maximum protrusion amount of the protrusion is set to be the largest on the inner surface of the rim portion in the rear region of the bowl portion, so that the cleaning water swirling on the inner surface of the rim portion can be reliably caused to collide with the protrusion and flow down.

[0009] In the present invention, the inner peripheral surface of the rim portion below the protrusion is preferably formed so that the radius of curvature of the inner peripheral surface in a plan view is the smallest of any of the entire circumference of the bowl portion. In the present invention configured in this way, the inner peripheral surface of the rim portion below the protrusion is formed so that the radius of curvature of the inner peripheral surface in a plan view is the smallest of the entire circumference of the bowl portion, which can impart a relatively large pressure loss to the swirling flush water, causing the flush water to spread vertically and collide with the protrusion.

[0010] In the present invention, the upper edge of the waste receiving surface is preferably inclined upward from the front end thereof toward the protruding portion. In the present invention configured in this manner, the upper edge of the waste receiving surface is inclined upward from its front end toward the protruding portion, so that the cleaning water swirling around the upper edge of the waste receiving surface can be guided toward the protruding portion, causing the cleaning water to collide with the protruding portion.

[0011] In the present invention, preferably, the inner surface of the rim portion above the second water outlet is provided with an inclined portion that slopes upward toward the inside of the bowl portion, and this inclined portion is provided downstream of the protrusion. In the present invention configured in this manner, an inclined portion is provided on the inner surface of the rim portion above the second water outlet, sloping upward toward the inside of the bowl portion, so that flushing water that passes over the protrusion without flowing downward can be made to flow downward by the inclined portion. [Effects of the Invention]

[0012] According to the flush toilet of the present invention, it is possible to provide a flush toilet that can improve waste discharge performance even if the pooling surface is formed larger than before. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a side view of a flush toilet according to an embodiment of the present invention. [Figure 2] FIG. 2 is a cross-sectional view taken along line II-II in FIG. [Figure 3] FIG. 3 is a partially enlarged view showing the vicinity of the second spout in the bowl portion of the flush toilet according to the embodiment of the present invention shown in FIG. 2. [Figure 4A] FIG. 4 is a cross-sectional view taken along line IVA-IVA in FIG. 3. [Figure 4B] FIG. 4 is a cross-sectional view taken along line IVB-IVB in FIG. 3. [Figure 4C] FIG. 4 is a cross-sectional view taken along the line IVC-IVC in FIG. 3. [Figure 5A] FIG. 4 is a cross-sectional view taken along the line VA-VA in FIG. 3. [Figure 5B] FIG. 4 is a cross-sectional view taken along line VB-VB in FIG. 3. [Figure 6] FIG. 2 is a perspective view showing a schematic view of the flow of flush water in the bowl portion of a flush toilet according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0014] Below, we will explain a flush toilet 1 according to an embodiment of the present invention. First, the basic structure of the flush toilet 1 will be explained using Figures 1 and 2. Figure 1 is a side view of a flush toilet according to an embodiment of the present invention, and Figure 2 is a cross-sectional view taken along line II-II in Figure 1.

[0015] In this specification, when a user looks at flush toilet 1 from the front, the front of flush toilet 1 will be described as the "front side," the back side as the "rear side," the right side as the "right side," the left side as the "left side," the front-to-back direction of flush toilet 1 as the "front-to-back direction," the left-to-right direction as the "left-to-right direction," and the up-to-down direction as the "vertical direction."

[0016] As shown in Figures 1 and 2, flush toilet 1 is a wash-down toilet that flushes away waste by the flowing water caused by the headway of water in the bowl. Flush toilet 1 comprises a ceramic toilet body 2 and a water storage tank 4 that stores flush water for cleaning toilet body 2. A bowl 6 is formed in the front of toilet body 2, and a common water conduit 8 that communicates with water storage tank 4 is formed in the upper rear part of bowl 6. Furthermore, a drainage pipe 10 is formed in the lower rear part of bowl 6 for discharging waste. In the embodiments of the present invention, a wash-down toilet will be described, but the present invention is not limited to this, and the flush toilet of the present invention also includes a siphon toilet that discharges waste by siphon action.

[0017] The above-mentioned water tank 4 is equipped with a drain valve 12, and when the user opens an operating lever (not shown), the drain valve 12 opens and flush water in the water tank 4 is supplied to the toilet body 2. Furthermore, in the flush toilet of the present invention, other than the water storage tank 4, the flush water source may be one that uses direct tap water pressure or a flush valve, or it may even be one that supplies flush water using a pump.

[0018] The bowl portion 6 comprises a bowl-shaped waste receiving surface 14, a rim portion 16 formed above the waste receiving surface 14 and having an inner peripheral surface 16a exposed to the outside, and a basin portion 18 formed below the waste receiving surface 14 and forming a water collection surface W therein. The water collection surface W of the basin portion 18 is approximately triangular in plan view, measuring 160 mm to 180 mm in the front-to-back direction and 125 mm to 145 mm in the horizontal direction, and is larger (enlarged) than the water collection surface of a conventional wash-down toilet. The basin portion 18 is also 200 mm to 240 mm in the front-to-back direction and 150 mm to 190 mm in the horizontal direction in plan view, forming an approximately triangular shape that is egg-shaped (an oval shape tapering at the front) larger than the water collection surface W.

[0019] The pot portion 18 of the bowl portion 6 has a bottom wall 18a that forms the bottom surface, and a side wall 18b that extends almost vertically upward from the outer edge of the bottom wall 18a. In this way, the pot portion 18 is formed into a pot-like shape by the bottom wall 18a and the side wall 18b, and is capable of storing water inside.

[0020] A first water outlet 20 that spouts flush water is formed at the front left side of the rim portion 16 of the bowl portion 6, and a second water outlet 22 that spouts flush water is formed at the rear right side. The above-mentioned common water conduit 8 branches downstream into a first water conduit 24 and a second water conduit 26, with the first water conduit 24 extending to the first water outlet 20 and the second water conduit 26 extending to the second water outlet 22, and flush water is supplied from the water storage tank 4 to the first water outlet 20 and the second water outlet 22.

[0021] First water outlet 20 spouts flush water towards the front of bowl portion 6, and second water outlet 22 spouts flush water towards the rear of bowl portion 6. First water outlet 20 and second water outlet 22 are designed to form a swirling flow in the same counterclockwise direction on waste receiving surface 14. Furthermore, in the case of an embodiment of the present invention, of the amount of flush water supplied from water storage tank 4 to common water conduit 8, the ratio between the amount of flush water spouted from first water outlet 20 and the amount of flush water spouted from second water outlet 22 is approximately 6:4, which means that the amount of flush water spouted from second water outlet 22 is greater than in the past. Furthermore, the flush toilet of the present invention may have one water outlet, or may have two or more (for example, three).

[0022] The drainage pipe 10 is equipped with an inlet 10a connected to the bottom wall 18a of the pot portion 18, an introduction pipe 10b extending downward and rearward from the inlet 10a, an ascending pipe 10c extending upward and rearward from the introduction pipe 10b, a descending pipe 10d extending downward and rearward from the ascending pipe 10c, and a top portion 10e located between the descending pipe 10d and the ascending pipe 10c and determining the water level of the pooled water surface W before the start of flushing. The introduction pipe 10b is connected to the bottom wall 18a of the pot portion 18 as a smooth, continuously curved surface, allowing the flush water flowing in from the inlet 10a to flow smoothly. Here, the lower end of the descending pipe 10d of the drain pipe 10 is connected to a drain pipe (not shown) via a drain socket (not shown).

[0023] Next, the structure of the bowl portion 6 of a flush toilet 1 according to an embodiment of the present invention will be explained in detail using Figures 2 to 4C. Figure 3 is a partially enlarged view of the area around the second spout 22 in the bowl portion 6 of the flush toilet 1 according to the embodiment of the present invention shown in Figure 2, Figure 4A is a cross-sectional view taken along line IVA-IVA in Figure 3, Figure 4B is a cross-sectional view taken along line IVB-IVB in Figure 3, and Figure 4C is a cross-sectional view taken along line IVC-IVC in Figure 3. 2 and 3, the dotted line drawn on the inside of the bowl portion 6 indicates the innermost end 16b of the rim portion 16 (the upper opening of the bowl portion 6) when the flush toilet 1 is viewed from above. Additionally, the cross-sectional views in Figures 4A to 4C show cross sections perpendicular to the direction of flow of flush water swirling around the inner circumferential surface 16a of the rim portion 16.

[0024] As shown in Figure 1, the rim portion 16 of the bowl portion 6 is formed with a first spout 20 for spouting flush water at a position on the front left side, as described above, and a second spout 22 for spouting flush water at a position on the rear right side. Also, as shown in Figure 2, the rim portion 16 is formed with an inner circumferential surface 16a that extends upward from the upper edge 14a of the waste receiving surface 14 around almost the entire circumference. The inner circumferential surface 16a of the rim portion 16, together with the upper edge 14a of the waste receiving surface 14, forms a water conduit through which flush water spouted from the first spout 20 and the second spout 22 flows. The flush water spouted from the first spout 20 and the second spout 22 flows in the same direction over the upper edge 14a and inner circumferential surface 16a, forming a swirling flow.

[0025] As shown in Figures 2 and 3, a protrusion 30 is formed on the inner circumferential surface 16a of the rim portion 16 near the upstream side of the second water outlet 22 (immediately upstream of the second water outlet 22) that protrudes toward the inside of the bowl portion 6 (the area 30 surrounded by dotted lines in Figures 2 and 3). The protrusion 30 is located to the rear right of the basin portion 18 in a plan view of the bowl portion 16, and is located at the most downstream side of the inner circumferential surface 16a of the rim portion 16 from the first water outlet 20 to the second water outlet 22. With this configuration, flush water discharged from the first water outlet 20 swirls around the inner circumferential surface 16a of the rim portion 16 before colliding with the protrusion 30 and flowing down towards the basin portion 18. The volume of flush water that collides with the protrusion 30 and flows down is approximately 30 percent of the total volume of water discharged from the first water outlet 20.

[0026] 4A to 4C, the protrusions 30 are formed on the upper portion of the inner circumferential surface 16a (above the center line that vertically bisects the inner circumferential surface 16a). No protrusions 30 are formed on the lower portion of the inner circumferential surface 16a (below the center line that vertically bisects the inner circumferential surface 16a), and the lower portion of the inner circumferential surface 16a extends in a substantially vertical direction. The protrusions 30 are connected to the inner circumferential surface 16a, which extends in a substantially vertical direction, as a smooth, continuously curved surface.

[0027] As shown in FIGS. 3 and 4A to 4C, protrusion 30 is formed to protrude upward toward the inside (center) of bowl portion 16. The protrusion amount D, by which innermost end 30a (innermost end 16b of rim portion 16) of protrusion 30 protrudes toward the inside of bowl portion 16 relative to lower end 16c of inner circumferential surface 16a of rim portion 16, gradually increases downstream in the swirling direction of flush water, reaches a maximum protrusion amount Dmax, and then gradually decreases downstream (see FIG. 3). In other words, protrusion amount D is set to decrease at upstream end 30b and downstream end 30c, reaching a maximum protrusion amount Dmax midway between upstream end 30b and downstream end 30c. The maximum protrusion amount Dmax of protrusion 30 is set to be greatest in the rear region of inner circumferential surface 16a of rim portion 16 (rearward of the center line that bisects bowl portion 6 in the front-to-rear direction).

[0028] As shown in Figures 4A to 4C, the protrusion 30 has a bottom surface 30d that faces downward. The bottom surface 30d is formed so that it slopes upward toward the inside of the bowl portion 6. The bottom surface 30d is also formed so that it is curved in an arc. The bottom surface 30d is formed from the upstream end 30b to the downstream end 30c in the swirling direction of the flush water. The bottom surface 30d is set so that its entire surface faces the pooled water surface W in the basin portion 18. When flush water collides with such a bottom surface 30d, the flow direction of the flush water changes from the swirling direction to a downward direction. In the flush toilet of this embodiment, the bottom surface 30d is formed so that it slopes upward toward the inside of the bowl, but it may also be formed so that it extends almost horizontally. Also, in the flush toilet of this embodiment, the bottom surface 30d is formed so that it curves in an arc, but it may also be formed so that it extends in a straight line.

[0029] 2, the inner circumferential surface 16a of the rim portion 16 below the protrusion 30 is formed so that the radius of curvature R of the inner circumferential surface 16a of the rim portion 16 is the smallest around the entire circumference of the bowl portion 6 in a plan view. When flush water flows along the inner circumferential surface 16a below the protrusion 30, the flush water is subjected to a relatively large pressure loss. As a result, the flush water spreads out in the vertical direction and collides with the bottom surface 30d of the protrusion 30.

[0030] 1, the upper edge 14a of the waste receiving surface 14 gradually slopes upward from its front end 14b toward the rear protruding portion 30. As flush water flows over this upper edge 14a, the flush water is guided toward the protruding portion 30. The flush water guided by the upper edge 14a collides with the bottom surface 30d of the protruding portion 30.

[0031] Next, the structure around the second discharge port 22 of a flush toilet 1 according to an embodiment of the present invention will be explained in detail using Figures 2, 3, 5A, and 5B. Figure 5A is a cross-sectional view taken along line VA-VA in Figure 3, and Figure 5B is a cross-sectional view taken along line VB-VB in Figure 3.

[0032] As shown in Figures 5A and 5B, an inclined portion 40 is formed on the inner peripheral surface 16a of the rim portion 16 above the second spout 22, sloping upward toward the inside of the bowl portion 6, and this inclined portion 40 is formed on the downstream side of the protruding portion 30 (the area 40 surrounded by dotted lines in Figures 2 and 3). The upstream end of the inclined portion 40 is continuously connected to the downstream end 30c of the protruding portion 30. Specifically, the inclined surface 40a of the inclined portion 40 and the bottom surface 30d of the protruding portion 30 are smoothly continuous with no steps (see Figure 6).

[0033] The distance d from the lower end 40b of the inclined portion 40 to the innermost end 40c (the innermost end 16b of the rim portion 16) is set to be greatest on the upstream side and to gradually decrease downstream in the swirling direction of the flush water (see Figure 3). With this configuration, flush water that passes over the protruding portion 30 without flowing downstream is made to flow downstream by the inclined portion 40.

[0034] Next, the flow of flush water within the bowl portion 6 during toilet flushing in a flush toilet 1 according to an embodiment of the present invention will be explained using Figure 6. Figure 6 is a perspective view showing, in outline, the flow of flush water in the bowl portion of a flush toilet according to an embodiment of the present invention.

[0035] When flushing begins, flush water F1 is discharged from the first water outlet 20 toward the front of the bowl portion 6, and flush water is discharged from the second water outlet 22 toward the rear of the bowl portion 6. Of the flush water discharged from the second water outlet, some flush water F2 swirls around the inner surface 16a of the rim portion 16, and most flush water F3 flows down the waste receiving surface 14 and flows directly into the water surface W in the basin portion 18. Flush water F1 discharged from the first water outlet 20 and flush water F2 discharged from the second water outlet 22 swirl in the same direction over the inner surface 16a of the rim portion 16 and the upper edge portion 14a of the waste receiving surface.

[0036] Flush water F1 discharged from first water outlet 20 flows over upper edge 14a, which slopes upward from front end 14b towards rear protrusion 30, and is therefore guided towards protrusion 30. Furthermore, as flush water F1 flows over inner circumferential surface 16a of rim portion 16 below protrusion 30, it experiences a relatively large pressure loss due to inner circumferential surface 16a having the smallest radius of curvature, and some of the flush water flows in a manner that spreads out vertically (F4). Furthermore, the remaining flush water F5 continues to swirl and merges with flush water F2 discharged from second water outlet 22.

[0037] Flush water F4, which has spread out vertically, collides with the bottom surface 30d of the protruding portion 30, and its flow direction changes directly from the swirling direction to downward (F6). Flush water F6 flows down towards the pooled water surface W in the basin portion 18. In this way, the flow direction changes directly from the swirling direction to downward by the bottom surface 30d of the protruding portion 30, so the force of the flush water flowing down towards the pooled water surface W in the basin portion 18 can be strengthened. Furthermore, flush water F6 joins with flush water F3, which flows directly into the pooled water surface W in the basin portion 18 from the second water outlet 22, and the two flow together into the pooled water surface W in the basin portion 18. As a result, the force pushing in the waste can be strengthened.

[0038] Furthermore, flush water F7 that passes over protruding portion 30 without flowing downward is caused to flow downward by inclined surface 40a of inclined portion 40 formed above second water discharge port 22.

[0039] Next, the effects of the flush toilet 1 according to the embodiment of the present invention described above will be explained. First, with the flush toilet 1 according to the embodiment of the present invention, a protrusion 30 that protrudes toward the inside of the bowl section 6 is provided on the upper part of the inner circumferential surface 16a of the rim section 16, near the upstream side of the second spout 22, and this protrusion 30 has a bottom surface 30d that is configured to change the flow direction of flush water flowing along the inner circumferential surface 16a of the rim section 16 downward, so that the bottom surface 30d of the protrusion 30 can directly change the flow direction downward, and can increase the momentum of the flush water flowing down toward the pooled water surface W in the basin section 18. As a result, the force that pushes in waste can be increased, and waste discharge performance can be improved even if the pooled water surface W is made larger than before.

[0040] In a flush toilet 1 according to an embodiment of the present invention, the amount of protrusion D by which the innermost end 30a of the protrusion 30 protrudes into the bowl portion 6 relative to the lower end 16c of the inner surface 16a of the rim portion 16 increases downstream and then decreases, making it possible to make the protrusion 30 less noticeable and allowing the flush water swirling around the inner surface 16a of the rim portion 16 to collide with the protrusion 30 and flow down.

[0041] Furthermore, according to the flush toilet 1 of the embodiment of the present invention, the maximum protrusion amount Dmax of the protrusion 30 is set to be the largest on the inner surface 16a of the rim portion 16 in the rear region of the bowl portion 6, so that the flush water swirling on the inner surface 16a of the rim portion 16 can be reliably caused to collide with the protrusion 30 and flow down.

[0042] In a flush toilet 1 according to an embodiment of the present invention, the inner circumferential surface 16a of the rim portion 16 below the protruding portion 30 is formed so that the radius of curvature R of the inner circumferential surface 16a in a plan view is the smallest of the entire circumference of the bowl portion 6, and so a relatively large pressure loss can be applied to the swirling flush water. As a result, the flush water spreads out vertically, allowing it to collide with the protruding portion 30.

[0043] Furthermore, according to the flush toilet 1 of the embodiment of the present invention, the upper edge 14a of the waste receiving surface 14 is inclined upward from its front end 14b towards the protruding portion 30, so that the flush water swirling around the upper edge 14a of the waste receiving surface 14 can be guided towards the protruding portion 30, causing the flush water to collide with the protruding portion 30.

[0044] In a flush toilet 1 according to an embodiment of the present invention, an inclined portion 40 is provided on the inner surface 16a of the rim portion 16 above the second spout 22, sloping upward toward the inside of the bowl portion 6, and this inclined portion 40 is provided downstream of the protruding portion 30, so that flush water that passes over the protruding portion 30 without flowing downward can be made to flow downward by the inclined portion 40.

[0045] The present invention is not limited to the above-described embodiments, and various changes and modifications are possible within the scope of the technical concept described in the claims. [Explanation of symbols]

[0046] 1: Flush toilet 6: Bowl section 10: Drainage pipe 10a: Drainage pipe inlet 14: Waste receiving surface 14a: Upper edge of waste receiving surface 14b: Front end of waste receiving surface 16: Rim 16a: Inner surface of rim 16b: Innermost edge of rim 16c: Lower end of inner circumferential surface of rim 18: Pressure points 20: First outlet 22: Second outlet 30:Protrusion 30a: innermost end of protrusion 30b: upstream end of protrusion 30c: downstream end of protrusion 30d: Bottom of protrusion 40: Inclined part 40a: Inclined surface of inclined portion 40b: Lower end of inclined portion 40c: Innermost end of the slope D: Protrusion amount of the protrusion Dmax: Maximum protrusion of the protrusion R: radius of curvature W: Reservoir surface

Claims

1. A flush toilet that discharges waste using flush water supplied from a flush water source, a bowl portion including a bowl-shaped waste receiving surface, a rim portion formed above the waste receiving surface and having an inner peripheral surface, and a basin portion formed below the waste receiving surface and having a water collecting surface formed therein; a first water discharge port provided in the rim portion on one side of the bowl portion in the left-right direction, the first water discharge port discharging flush water along the inner circumferential surface of the rim portion to form a swirling flow; a second water outlet provided on the rim portion on the other left-right side of the bowl portion, which discharges flush water along the inner circumferential surface of the rim portion in the same direction as the swirling direction of flush water discharged from the first water outlet; a drainage pipe connected to the pot portion for discharging waste; and A protrusion that protrudes toward the inside of the bowl portion is provided on an upper part of the inner circumferential surface of the rim portion near the upstream side of the second water outlet, A flush toilet characterized in that this protrusion has a bottom surface configured to change the flow direction of flush water flowing along the inner circumferential surface of the rim portion downward.

2. 2. The flush toilet according to claim 1, wherein the amount by which the innermost end of the protrusion protrudes inwardly into the bowl portion relative to the lower end of the inner circumferential surface of the rim portion increases toward the downstream side and then decreases thereafter.

3. 3. The flush toilet according to claim 2, wherein the maximum amount of protrusion of the protrusion is set to be the greatest on the inner circumferential surface of the rim portion in the rear region of the bowl portion.

4. The flush toilet according to any one of claims 1 to 3, wherein the inner circumferential surface of the rim portion below the protrusion is formed so that the radius of curvature of the inner circumferential surface in a plan view is the smallest around the entire circumference of the bowl portion.

5. 5. The flush toilet according to claim 4, wherein the upper edge of the waste receiving surface slopes upward from its front end toward the protruding portion.

6. 2. The flush toilet according to claim 1, wherein the inner peripheral surface of the rim portion above the second spout is provided with an inclined portion that slopes upward toward the inside of the bowl portion, and this inclined portion is provided downstream of the protrusion.

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