IP Library › Granted Patent US 12,421,708
Granted Patent B2
US 12,421,708 · App. 18/174,261 · Granted Sep 23, 2025

Flush toilet

Inventors: Shoko Kobayashi (Kitakyushu, JP); Makoto Bekki (Kitakyushu, JP); Daiki Okabe (Kitakyushu, JP)
Assignee: TOTO LTD.
E03D11/08
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Quick Facts
Patent No.
US 12,421,708
App. No.
18/174,261
Granted
Sep 23, 2025
Kind
B2
Abstract

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 and a rearward main flow of flush water spouted from the spouting ports circulate around a waste receiving surface of a bowl and flow, in the beginning of flushing start, into three or more regions of the pooled water surface divided into four regions.

Claims (19)

1. A flush toilet that is flushed with flush water to discharge waste, the flush toilet comprising:

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;

a first spouting port and a second spouting port that spout flush water along the rim, wherein the first spouting port forms a forward main flow and the second spouting port forms a rearward main flow, the first spouting port is disposed on one of left and right sides of a front region of the waste receiving surface of a bowl surface, the second spouting port is disposed on the other of the left and right sides of a rear region of the waste receiving surface of the bowl surface; and

a discharge conduit connected to a bottom portion of the bowl,

wherein the first spouting port is disposed in front of a front end of the pooled water surface and the second spouting port is disposed behind a rear end of the pooled water surface;

wherein the forward main flow and the rearward main flow circulate around the waste receiving surface of the bowl and flow, in the beginning of flushing start which is an initial flushing period among three divided periods from a start of flush water flowing into the pooled water surface to an end of the flush water flowing into the pooled water surface, into three or more regions of the pooled water surface divided into four regions by a front-rear centerline and a left-right centerline that divide the pooled water surface into two parts in a front-rear direction and a left-right direction in a planar view; and

wherein a predetermined energy accumulated amount of flush water flowing into the pooled water surface reaches, within one second, three or more regions of the pooled water surface divided into four regions.

2. The flush toilet according to claim 1 , wherein the forward main flow and the rearward main flow of flush water flow into the pooled water surface without joining each other.

3. The flush toilet according to claim 1 , wherein the forward main flow and the rearward main flow of flush water flow into different regions of a region divided into four regions, respectively.

4. The flush toilet according to claim 1 , wherein the forward main flow mainly flows into the rear region on one of the left and right sides on which the first spouting port is not provided in the pooled water surface divided into four regions, and the rearward main flow mainly flows into the front region on one of the left and right sides on which the second spouting port is not provided in the pooled water surface divided into four regions.

5. The flush toilet according to claim 1 , wherein a rear surface of the waste receiving surface of the bowl comprises a concave portion recessed deeper than left and right side surfaces of the waste receiving surface, and the rear surface extends to below an upper end of left and right side surfaces of the well portion.

6. The flush toilet according to claim 5 , wherein the concave portion on the rear surface of the waste receiving surface of the bowl is formed so that a lateral width of the concave portion is smaller than a maximum lateral width of the well portion.

7. The flush toilet according to claim 5 , wherein the concave portion on the rear surface of the waste receiving surface of the bowl is formed in a concave shape along an up-down direction and has a lower end connected to a rear surface of the well portion by a convex-shaped connecting portion.

8. The flush toilet according to claim 5 , wherein the well portion is formed so that, in a curvature radius R 1 at an upper position of a rear surface of the well portion and a curvature radius R 2 at a lower position, the curvature radius R 2 at the lower position is smaller than the curvature radius R 1 at the upper position.

9. The flush toilet according to claim 1 , wherein the first rim spouting port and the second rim spouting port are arranged on a left side of a left end of the pooled water surface or on a right side of a right end of the pooled water surface.

10. The flush toilet according to claim 1 , wherein the first rim spouting port and the second rim spouting port, in a planar view, are arranged in regions, respectively, that are diagonal so as to sandwich an intersection point at which a centerline that divides the pooled water surface into two equal parts in a left-right direction and a centerline that divides the pooled water surface into two equal parts in a front-rear direction intersect.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Feb 24, 2023
From: KOBAYASHI, SHOKO; BEKKI, MAKOTO; OKABE, DAIKI
To: TOTO LTD.
Reel/Frame 062799/0482 →
Priority Claims (3)
JP 2022-029681 · Feb 28, 2022 · national
JP 2022-029682 · Feb 28, 2022 · national
JP 2022-029685 · Feb 28, 2022 · national
Continuity (1)
Related Publication 20230272607A1 · Aug 31, 2023
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