FLUSH TOILET

Description

CROSS REFERENCES TO RELATED APPLICATIONS

The present invention contains subject matter related to Japanese Patent Application No. 2024-149965 filed in the Japan Patent Office on Aug. 30, 2024, the entire contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a flush toilet and relates, in particular, to a flush toilet of a wall-mounted type.

2. Description of the Related Art

As a wall-mounted flush toilet that is to be fixed to a wall surface, a wall-mounted flush toilet in which a water storage tank that stores flush water to be supplied to a toilet body is accommodated in a space that is inside the toilet body and that is located below a bowl has been known as described in Japanese Unexamined Patent Application Publication No. 2024-031498, Japanese Unexamined Patent Application Publication No. 2024-031499, and the specification of Chinese Utility Model No. 219825498. Such a flush toilet includes, inside the toilet body, a large number of functional devices such as a pump device configured to supply flush water from the water storage tank to the toilet body, a control device configured to drive the pump device, and the like.

SUMMARY OF THE INVENTION

Incidentally, it is conceivable to design a wall-mounted flush toilet, such as that described in Japanese Unexamined Patent Application Publication No. 2024-031498, Japanese Unexamined Patent Application Publication No. 2024-031499, or the specification of Chinese Utility Model No. 219825498, so as to have a low silhouette by reducing the height dimension of a toilet body in the up-down direction. However, since the space inside the toilet body is narrowed when the wall-mounted flush toilet, such as that in Japanese Unexamined Patent Application Publication No. 2024-031498, Japanese Unexamined Patent Application Publication No. 2024-031499, or the specification of Chinese Utility Model No. 219825498, is designed to have a low silhouette, the water storage tank may interfere with a functional device and make it impossible to accommodate the water storage tank inside the toilet body.

The present invention has been conceived to solve the above-described problem and is intended to provide a flush toilet that is capable of accommodating a tank device inside a toilet body while the capacity of the tank device is ensured.

To solve the problem described above, the present invention is a flush toilet that is a wall-mounted flush toilet, the flush toilet including a toilet body including a bowl configured to receive waste, a drain trap pipeline connected to a lower portion of the bowl and configured such that waste is discharged along the drain trap pipeline, and a skirt surrounding the bowl and the drain trap pipeline from outside; a tank device disposed in a space that is inside the toilet body and that is located below the bowl, the tank device being configured to store flush water that is to be supplied to the toilet body; and a functional device configured to supply flush water to the toilet body, in which the tank device includes a first tank portion and a second tank portion that are arranged on one side and another side, respectively, with respect to a center of the toilet body in a left-right direction in top view, and in which a length of the second tank portion in a front-rear direction is set to be less than or equal to half a length of the first tank portion in the front-rear direction.

According to the present invention that is thus configured, it is possible to accommodate the functional devices in the rear region behind the second tank portion and possible to compactly accommodate the tank device and the functional devices in the space inside the toilet body due to the configuration in which the tank device includes the first tank portion and the second tank portion that are arranged on one side and the other side, respectively, with respect to the center of the toilet body in the left-right direction in top view and in which the length of the second tank portion in the front-rear direction is set to be less than or equal to half the length of the first tank portion in the front-rear direction. Consequently, it is possible to accommodate the tank device inside the toilet body while ensuring the capacity of the tank device.

In the present invention, preferably, the tank device includes a coupling portion configured to couple the first tank portion and the second tank portion to each other, and the coupling portion is arranged at a center of the bowl in the front-rear direction in top view.

In the present invention that is thus configured, it is possible to freely design the shape of the skirt in front of the toilet body, compared with when the coupling portion is arranged in front of the bowl, due to the configuration in which the tank device includes the coupling portion coupling the first tank portion and the second tank portion to each other and in which the coupling portion is arranged at the center of the bowl in the front-rear direction in top view.

In addition, in the present invention, preferably, there are included a jet water ejection port arranged at a lower portion of the bowl and configured such that flush water is ejected through the jet water ejection port toward an inlet of the drain trap pipeline and a jet water conduit configured such that flush water is supplied along the jet water conduit to the jet water ejection port, an upper surface wall of the coupling portion has a concave shape, and the jet water conduit is arranged at the upper surface wall having the concave shape.

In the present invention that is thus configured, it is possible to avoid interference of the tank device with the jet water conduit due to the configuration in which there are included the jet water ejection port arranged at a lower portion of the bowl and configured such that flush water is ejected through the jet water ejection port toward the inlet of the drain trap pipeline and the jet water conduit configured such that flush water is supplied along the jet water conduit to the jet water ejection port, in which the upper surface wall of the coupling portion has a concave shape, and in which the jet water conduit is arranged at the upper surface wall having the concave shape.

In the present invention, preferably, an upper surface wall of the second tank portion is set to be lower than an upper surface wall of the first tank portion.

In the present invention that is thus configured, it is possible to reduce a space in which air accumulates inside the second tank portion and make the tank device compact due to the configuration in which the upper surface wall of the second tank portion is set to be lower than the upper surface wall of the first tank portion.

In addition, in the present invention, preferably, a water-stop water level in the first tank portion is set to be higher than a water-stop water level in the second tank portion.

In the present invention that is thus configured, it is possible, even when the tank device is made compact, to store a large amount of flush water due to the configuration in which the water-stop water level in the first tank portion is set to be higher than the water-stop water level in the second tank portion.

In the present invention, preferably, the functional device is a pump device configured to deliver flush water, which is stored in the tank device, under pressure to the toilet body.

In the present invention that is thus configured, it is possible to accommodate the tank device and the pump device compactly in the space inside the toilet body due to the configuration in which a functional device is the pump device configured to deliver the flush water, which is stored in the tank device, under pressure to the toilet body.

In addition, in the present invention, preferably, there are further included a jet water ejection port arranged at a lower portion of the bowl and configured such that flush water is ejected through the jet water ejection port toward an inlet of the drain trap pipeline, a jet water conduit configured such that flush water is supplied along the jet water conduit to the jet water ejection port, and a jet water supply pipe connecting the jet water conduit and the pump device to each other, and the pump device and the jet water supply pipe are accommodated in a space that is inside the toilet body and that is located behind the second tank portion.

In the present invention that is thus configured, it is possible to accommodate the tank device, the pump device, and the jet water supply pipe compactly in the space inside the toilet body due to the configuration in which there are included the jet water ejection port arranged at a lower portion of the bowl and configured such that flush water is ejected through the jet water ejection port toward the inlet of the drain trap pipeline, the jet water conduit configured such that flush water is supplied along the jet water conduit to the jet water ejection port, and the jet water supply pipe connecting the jet water conduit and the pump device to each other and in which the pump device and the jet water supply pipe are accommodated in the space that is inside the toilet body and that is located behind the second tank portion.

In the present invention, preferably, there are further included a rim water ejection port arranged at a rim portion of the bowl and configured such that flush water is ejected through the rim water ejection port, a rim water conduit configured such that flush water is supplied along the rim water conduit to the rim water ejection port, and a rim water supply pipe connecting the rim water conduit and the pump device to each other, and the pump device and the rim water supply pipe are accommodated in a space that is inside the toilet body and that is located behind the second tank portion.

In the present invention that is thus configured, it is possible to accommodate the tank device, the pump device, and the rim water supply pipe compactly in the space inside the toilet body due to the configuration in which there are included the rim water ejection port arranged at the rim portion of the bowl and configured such that flush water is ejected through the rim water ejection port, the rim water conduit configured such that flush water is supplied along the rim water conduit to the rim water ejection port, and the rim water supply pipe connecting the rim water conduit and the pump device to each other and in which the pump device and the rim water supply pipe are accommodated in the space that is inside the toilet body and that is located behind the second tank portion.

In addition, in the present invention, preferably the pump device is disposed near the second tank portion.

In the present invention that is thus configured, it is possible to accommodate the tank device and the pump device compactly in the space inside the toilet body due to the configuration in which the pump device is disposed near the second tank portion.

In the present invention, preferably, the second tank portion is provided with an outflow pipeline configured such that flush water stored in the tank device flows out along the outflow pipeline, and an outlet of the outflow pipeline is arranged to face an inflow port of the pump device.

In the present invention that is thus configured, it is possible to compactly connect the tank device and the pump device to each other due to the configuration in which the second tank portion is provided with the outflow pipeline configured such that the flush water stored in the tank device flows out along the outflow pipeline and in which the outlet of the outflow pipeline is arranged to face the inflow port of the pump device.

In addition, in the present invention, preferably, an inlet of the outflow pipeline of the second tank portion is open downward.

In the present invention that is thus configured, it is possible to lower the dead water level of the flush water inside the tank device and possible to make the tank device compact due to the configuration in which the inlet of the outflow pipeline of the second tank portion is open downward.

In the present invention, preferably, the tank device includes a sectional-area decreasing portion where a horizontal cross-sectional area of the tank device decreases toward an upper portion of the tank device and a float switch configured to detect a water level of flush water stored in the tank device, and the float switch is disposed at the sectional-area decreasing portion.

In the present invention that is thus configured, it is possible to increase the water-level rising speed inside the sectional-area decreasing portion and cause the float switch to operate and possible to improve accuracy in detection of the water level by the float switch due to the configuration in which the tank device includes the sectional-area decreasing portion where the horizontal cross-sectional area of the tank device decreases toward an upper portion of the tank device and the float switch that detects the water level of the flush water stored in the tank device and in which the float switch is disposed at the sectional-area decreasing portion.

According to the flush toilet of the present invention, it is possible to accommodate the tank device inside the toilet body while ensuring the capacity of the tank device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view illustrating a flush toilet according to a first embodiment of the present invention.

FIG. 2 is a top view of the flush toilet according to the first embodiment of the present invention in a state in which a hygienic cleaning device is removed.

FIG. 3 is a side sectional view along the line III-III in FIG. 2.

FIG. 4A is a left perspective view of functional devices of the flush toilet according to the first embodiment of the present invention as viewed from above obliquely.

FIG. 4B is a right perspective view of the functional devices of the flush toilet according to the first embodiment of the present invention as viewed from above obliquely.

FIG. 5 is a block diagram illustrating a water supply path along which flush water of the flush toilet according to the first embodiment of the present invention flows.

FIG. 6A is a left perspective view of a tank device of the flush toilet according to the first embodiment of the present invention as viewed from above obliquely.

FIG. 6B is a right perspective view of the tank device of the flush toilet according to the first embodiment of the present invention as viewed from above obliquely.

FIG. 7 is a side sectional view along the line VII-VII in FIG. 6A.

FIG. 8 is a side sectional view along the line VIII-VIII in FIG. 6A.

FIG. 9 is a front sectional view along the line IX-IX in FIG. 6A.

FIG. 10 is a top view illustrating a positional relationship between the toilet body and the tank device of the flush toilet according to the first embodiment of the present invention.

FIG. 11 is a side sectional view illustrating an arrangement of the functional devices of the flush toilet according to the first embodiment of the present invention.

FIG. 12 is a left perspective view of a tank device of a flush toilet according to a second embodiment of the present invention as viewed from above obliquely.

FIG. 13 is a top view illustrating a positional relationship between a toilet body and the tank device of the flush toilet according to the second embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, a flush toilet 1 according to the first embodiment of the present invention will be described with reference to the accompanying drawings.

First, a basic structure of the flush toilet 1 according to the first embodiment of the present invention will be described with reference to FIG. 1 to FIG. 3.

FIG. 1 is a perspective view illustrating the flush toilet according to the first embodiment of the present invention, FIG. 2 is a top view of the flush toilet according to the first embodiment of the present invention in a state in which a hygienic cleaning device is removed, and FIG. 3 is a side sectional view along the line III-III in FIG. 2. In FIG. 2, a rim water conduit, a jet water conduit, and a jet water supply pipe are illustrated with dotted lines.

Note that description in the present specification is based on that the near side, the far side, the left side, and the right side of the flush toilet as viewed from the front is “front”, “rear”, “left”, and “right”, respectively.

As illustrated in FIG. 1, the flush toilet 1 according to the first embodiment of the present invention is a flush toilet of a wall-mounted type that is to be fixed at the back surface thereof to a wall surface W. The flush toilet 1 includes a toilet body 2 made of porcelain, a tank device 4 configured to store flush water that is to be supplied to the toilet body 2, and a hygienic cleaning device 6 placed on the upper surface of the toilet body 2. The wall surface W is provided with a stop valve 8 configured to supply flush water, which is from a water supply source (not illustrated) such as a water supply, to the flush toilet 1 or stop the supply of the flush water. The stop valve 8 is connected to the flush toilet 1 through a water supply pipe 10.

As illustrated in FIG. 2 and FIG. 3, in the toilet body 2, there are formed a bowl 12 that receives waste, a drain trap pipeline 14 connected to a lower portion of the bowl 12 to drain waste, and a skirt 16 surrounding the bowl 12 and the drain trap pipeline 14 from the outside. A space S inside the toilet body 2 is formed between the skirt 16 and each of the bowl 12 and the drain trap pipeline 14.

The bowl 12 includes a bowl-shaped waste receiving surface 18 and a rim portion 20 formed along an upper edge portion of the bowl 12. Water is to be retained inside the bowl 12.

In the rim portion 20, there are formed a rim water ejection port 22 configured such that flush water is ejected rearward through the rim water ejection port 22 and a rim water conduit 24 configured such that flush water is guided along the rim water conduit 24 to the rim water ejection port 22. The rim water ejection port 22 is arranged, on the right side of the bowl 12, close to the center of the bowl 12 in the front-rear direction. The flush water ejected from the rim water ejection port 22 flows downward to the waste receiving surface 18 while swirling along the inner circumferential surface of the rim portion 20, thereby flushing the bowl 12.

At a lower portion of the bowl 12, there are formed a jet water ejection port 26 configured such that flush water is ejected through the jet water ejection port 26 toward an inlet 14a of the drain trap pipeline 14 and a jet water conduit 28 configured such that flush water is supplied along the jet water conduit 28 to the jet water ejection port 26. The jet water ejection port 26 is arranged to face the inlet 14a of the drain trap pipeline 14. The flush water ejected from the jet water ejection port 26 is caused to flow into the drain trap pipeline 14 and activate a siphon effect.

Although the flush toilet 1 according to the first embodiment of the present invention is a flush toilet of a siphon jet type that discharges waste by generating a siphon effect by jet water ejection, the flush toilet 1 is not limited to such a form and may be, for example as another form, a flush toilet of a wash-down type that washes away waste by a water flowing effect due to falling of water or a flush toilet of a siphon type that discharges waste by generating a siphon effect only by rim water ejection.

The drain trap pipeline 14 includes the inlet 14a connected to a lower portion of the bowl 12; a riser pipeline 14b extending upward from the inlet 14a; a top portion 14c arranged at a highest position in the riser pipeline 14b and configured to regulate the water level of retained water; and a rear pipeline 14d extending rearward from the top portion 14c substantially horizontally. The rear pipeline 14d of the drain trap pipeline 14 is connected to a drain pipe (not illustrated) inside the wall surface W through a drain socket 30.

The hygienic cleaning device 6 includes a body portion (not illustrated); a cleaning nozzle (not illustrated) provided so as to be able to advance and retract with respect to the body portion; a toilet seat (not illustrated) turnably attached to the body portion; and a toilet seat cover turnably attached to the body portion so as to cover the toilet seat. The water supply pipe 10 connected to the stop valve 8 is connected to the body portion of the hygienic cleaning device 6 and is configured such that flush water to be jetted from the cleaning nozzle is supplied along the water supply pipe 10.

As illustrated in FIG. 2 and FIG. 3, the space S inside the toilet body 2 is formed between the skirt 16 and each of the bowl 12 and the drain trap pipeline 14. The tank device 4 is accommodated in the space S that is inside the toilet body 2 and that is located below the bowl 12, the space S being surrounded by the skirt 16. In the space S that is inside the toilet body 2 and that is located behind the bowl 12, functional devices configured to supply flush water to the toilet body are accommodated. The functional devices are, for example, a water-supply-valve device 32, a pump device 34, a switch valve device 36, a control device 38, and the like. In addition, a base plate 40 is provided at a lower opening 2a that is surrounded by the skirt 16 of the toilet body 2, and the functional devices described above are supported by the base plate 40.

Next, with reference to FIG. 4A and FIG. 4B, the tank device 4, the functional devices, and the base plate 40, which are accommodated in the space S inside the toilet body 2, will be described.

FIG. 4A is a left perspective view of the functional devices of the flush toilet according to the first embodiment of the present invention as viewed from above obliquely, and FIG. 4B is a right perspective view of the functional devices of the flush toilet according to the first embodiment of the present invention as viewed from above obliquely. In FIG. 4A, a direction in which flush water flows is indicated by arrows.

The tank device 4 includes a water storage tank 42 configured to store flush water that is to be supplied to the toilet body 2; a tank water supply unit 46 configured to cause flush water from a tank water supply pipe 44 to flow into the water storage tank 42; a float switch 48 configured to detect a water level of the flush water stored in the water storage tank 42; and a fixation member 50 configured to fix the tank device 4 to the bottom surface of the toilet body 2.

The water storage tank 42 has an L-shape in top view and is formed to extend forward on the right side of the drain trap pipeline 14 and then extend to the left side by being bent. The water storage tank 42 is a resin tank that is configured to store flush water to be used for rim water ejection and jet water ejection and that is capable of storing approximately 4 liters of flush water.

The tank water supply unit 46 is disposed at an upper portion of the water storage tank 42. The upstream side of the tank water supply unit 46 is connected to the tank water supply pipe 44, and the downstream side of the tank water supply unit 46 is connected to the water storage tank 42. Inside the tank water supply unit 46, there is formed a flow path configured such that flush water from the tank water supply pipe 44 is guided along the flow path toward the water storage tank 42.

The float switch 48 is disposed at an upper portion of the water storage tank 42. The float switch 48 is configured to enter an off-state to cause the water-supply-valve device 32 to open when the water level in the tank falls below a water-stop water level (full water level) In addition, the float switch 48 is configured to enter an on-state to cause the water-supply-valve device 32 to close when the water level in the tank rises and reaches the water-stop water level.

An overflow unit 62 configured to discharge flush water to the outside of the tank, for example, when water supply to the tank is continued due to malfunction occurring in the float switch 48 is attached to the water storage tank 42. The overflow unit 62 is connected to the drain socket 30 and is configured such that flush water that has overflown from the water storage tank 42 is discharged into the drain socket 30 through the overflow unit 62.

The water-supply-valve device 32 includes a constant flow-rate valve (not illustrated) configured to make the flow rate of flush water constant; an on-off valve (not illustrated) provided downstream of the constant flow-rate valve and configured to switch supply and stop of flush water; and a solenoid valve (not illustrated) configured to drive the on-off valve. The upstream side of the water-supply-valve device 32 is connected to the water supply source (not illustrated) through the stop valve 8 and the water supply pipe 10, and the downstream side of the water-supply-valve device 32 is connected to the hygienic cleaning device 6 through a hygienic-cleaning-device water supply pipe 52 and is connected to the tank device 4 through the tank water supply pipe 44. When the solenoid valve electromagnetically opens, the on-off valve opens to cause flush water from the water supply source to be supplied to the tank device 4 through the tank water supply pipe 44.

The pump device 34 is a pressure-type pump and is configured to suction the flush water stored in the tank device 4 and deliver the flush water under pressure to the toilet body 2. The upstream side of the pump device 34 is connected to the tank device 4 through an upstream connection pipe 54, and the downstream side of the pump device 34 is connected to the switch valve device 36 through a downstream connection pipe 56. As a result of the pump device 34 operating, toilet flushing is performed by the flush water, which is stored in the tank device 4, being delivered under pressure and being ejected from the rim water ejection port 22 and the jet water ejection port 26. Note that, although the flush water stored in the tank device 4 is supplied to the rim water ejection port 22 and the jet water ejection port 26 in the flush toilet 1 according to the first embodiment of the present invention, the flush toilet 1 is not limited to such a form and is also applicable to, as another form, a form in which, for example, all of the flush water stored in the tank device 4 is ejected from the rim water ejection port 22.

The switch valve device 36 includes a switch valve body (not illustrated) and is configured to switch water supply paths along each of which the flush water supplied from the pump device 34 is supplied to a corresponding one of the rim water ejection port 22 and the jet water ejection port 26. The upstream side of the switch valve device 36 is connected to the pump device 34 through the downstream connection pipe 56, and the downstream side of the switch valve device 36 is connected to the rim water conduit 24 through a rim water supply pipe 58 and is connected to the jet water conduit 28 through a jet water supply pipe 60. In a state in which the switch valve body is closed, the flush water from the pump device 34 is supplied to the rim water ejection port 22, and, in a state in which the switch valve body is opened, the flush water from the pump device 34 is supplied to the rim water ejection port 22 and the jet water ejection port 26.

The control device 38 is electrically connected to a remote controller (not illustrated), the tank device 4 (float switch 48), the hygienic cleaning device 6, the water-supply-valve device 32, and the pump device 34 so as to be able to transmit and receive various signals. When the control device 38 receives a flushing start signal for full flushing or partial flushing from the remote controller, the control device 38 drives or stops the pump device 34 on the basis of a flushing sequence that is previously stored. Specifically, when the remote controller is operated by a user, the control device 38 drives the pump device 34 to cause the flush water stored in the tank device 4 to be ejected from the rim water ejection port 22 and the jet water ejection port 26. In addition, the control device 38 causes the water-supply-valve device 32 to open and supply water to the tank, and, when the float switch 48 detects a state of being filled with water, the control device 38 causes the water-supply-valve device 32 to close and terminate supply of water to the tank.

The pipes (the water supply pipe 10, the tank water supply pipe 44, the hygienic-cleaning-device water supply pipe 52, the upstream connection pipe 54, the downstream connection pipe 56, the rim water supply pipe 58, and the jet water supply pipe 60) connected to the functional devices described above have flexibility and can absorb manufacture errors and the like of the toilet body 2 made of porcelain.

Next, with reference to FIG. 5, a water supply path along which the flush water of the flush toilet 1 according to the first embodiment of the present invention flows will be described.

FIG. 5 is a block diagram illustrating a water supply path along which the flush water of the flush toilet according to the first embodiment of the present invention flows.

The stop valve 8, the water-supply-valve device 32, the tank device 4, the pump device 34, and the switch valve device 36 are disposed along the water supply path of the flush toilet 1 in this order from the upstream side. First, the flush water is supplied from the water supply source to the water-supply-valve device 32 through the stop valve 8 and the water supply pipe 10. The flush water supplied to the water-supply-valve device 32 is supplied to the hygienic cleaning device 6 through the hygienic-cleaning-device water supply pipe 52 and is supplied to the tank device 4 through the tank water supply pipe 44. The flush water stored in the tank device 4 is suctioned upward by the pump device 34 through the upstream connection pipe 54 and is supplied to the switch valve device 36 through the downstream connection pipe 56. The flush water supplied to the switch valve device 36 is ejected from the rim water ejection port 22 through the rim water supply pipe 58 and the rim water conduit 24 and is ejected from the jet water ejection port 26 through the jet water supply pipe 60 and the jet water conduit 28. In addition, the flush water that has overflowed from the tank device 4 is discharged to the drain socket 30 through the overflow unit 62.

Next, with reference to FIG. 6A to FIG. 9, the tank device 4 of the flush toilet 1 according to the first embodiment of the present invention will be described in detail.

FIG. 6A is a left perspective view of the tank device of the flush toilet according to the first embodiment of the present invention as viewed from above obliquely, FIG. 6B is a right perspective view of the tank device of the flush toilet according to the first embodiment of the present invention as viewed from above obliquely, FIG. 7 is a side sectional view along the line VII-VII in FIG. 6A, FIG. 8 is a side sectional view along the line VIII-VIII in FIG. 6A, and FIG. 9 is a front sectional view along the line IX-IX in FIG. 6A.

As illustrated in FIG. 6A and FIG. 6B, the water storage tank 42 of the tank device 4 has an L-shape in top view and is formed to be left-right asymmetric with respect to a central line CL at the center of the toilet body 2 in the left-right direction. The water storage tank 42 includes a first tank portion 70 arranged on the right side of the central line CL, a second tank portion 72 arranged on the left side of the central line CL, and a coupling portion 74 coupling the first tank portion 70 and the second tank portion 72 to each other. The height dimension of the first tank portion 70 in the up-down direction is set to be larger than the height dimension of the second tank portion 72 in the up-down direction, and the length of the first tank portion 70 in the front-rear direction is set to be larger than the length of the second tank portion 72 in the front-rear direction. Consequently, the capacity (volume) of the first tank portion 70 is set to be larger than the capacity of the second tank portion 72. In addition, since the length of the second tank portion 72 in the front-rear direction is set to be smaller than the length of the first tank portion 70 in the front-rear direction, it is possible to dispose the functional devices, such as the pump device 34 and the like, in a rear region A behind the second tank portion 72.

As illustrated in FIG. 7, in the first tank portion 70, the water level of stored water rises to a water-stop water level (full water level) WL1 and falls to a dead water level WL2. The first tank portion 70 includes a sectional-area constant portion 70a where the horizontal cross-sectional area of the first tank portion 70 is substantially constant and a sectional-area decreasing portion 70b where the horizontal cross-sectional area of the first tank portion 70 decreases toward an upper portion of the first tank portion 70. The water-level rising speed at the sectional-area decreasing portion 70b is higher than the water level rising speed at the sectional-area constant portion 70a. An inflow pipeline 70d extending in the up-down direction is formed at an upper surface wall 70c of the first tank portion 70, and the inflow pipeline 70d is connected to the tank water supply unit 46. Consequently, the flush water from the water supply source flows from the inflow pipeline 70d into the tank.

The float switch 48 that detects a water level of the flush water stored in the tank is fixed to the upper surface wall 70c of the first tank portion 70. The float switch 48 is disposed inside the sectional-area decreasing portion 70b of the first tank portion 70. The float switch 48 enters the off-state when the water level in the tank falls below the water-stop water level WL1 and enters the on-state when the water level in the tank rises and reaches the water-stop water level WL1.

At the first tank portion 70, there is disposed an overflow pipe 70e configured such that flush water is discharged to the outside of the tank through the overflow pipe 70e, for example, when water supply to the tank is continued due to malfunction occurring in the float switch 48. The overflow pipe 70e extends in the up-down direction and has an upper end that is connected to the overflow unit 62. Consequently, the flush water discharged from the overflow pipe 70e is discharged into the drain socket 30 through the overflow unit 62.

As illustrated in FIG. 8, in the second tank portion 72, the water level of stored water rises to a water-stop water level (full water level) WL3 and falls to a dead water level WL4. The water-stop water level WL3 in the second tank portion 72 is set to be lower than the water-stop water level WL1 in the first tank portion 70, and the dead water level WL4 in the second tank portion 72 is set to be at the same height as the dead water level WL2 in the first tank portion 70 (see FIG. 9). The second tank portion 72 is formed such that the horizontal cross-sectional area of the second tank portion 72 is substantially constant. The height dimension of the second tank portion 72 in the up-down direction is set to be approximately half the height dimension of the first tank portion 70 in the up-down direction at the sectional-area constant portion 70a, and an upper surface wall 72a of the second tank portion 72 is set to be lower than the upper surface wall 70c of the first tank portion 70. Consequently, a space in which air accumulates inside the second tank portion 72 is reduced, which makes the second tank portion 72 compact.

The length of the second tank portion 72 in the front-rear direction is set to be less than or equal to half, preferably, approximately one-third of the length of the first tank portion 70 in the front-rear direction. In addition, a rear surface wall 72b of the second tank portion 72 is formed by the same surface as a rear surface wall 74a of the coupling portion 74. Since the second tank portion 72 is thus formed to be smaller than the first tank portion 70, the rear region A, which is a space in which the functional devices such as the pump device 34 and the like can be disposed, is formed behind the rear surface wall 72b of the second tank portion 72 (see FIGS. 6A and 6B). The length of the rear region A in the front-rear direction is set to be approximately twice the length of the second tank portion 72 in the front-rear direction.

At the rear surface wall 72b of the second tank portion 72, an outflow pipeline 72c extending in the front-rear direction is formed. An outlet 72d of the outflow pipeline 72c is open rearward. In addition, an inlet 72e of the outflow pipeline 72c is open downward. The outlet 72d of the outflow pipeline 72c is connected to the upstream connection pipe 54 and is configured such that the flush water in the tank is supplied to the pump device 34 through the outlet 72d. The inlet 72e of the outflow pipeline 72c is open downward inside the second tank portion 72 and thus can lower the dead water levels WL2 and WL4.

As illustrated in FIG. 9, the coupling portion 74 is disposed between the first tank portion 70 and the second tank portion 72. The height dimension of the coupling portion 74 in the up-down direction is set to be smaller than the height dimension of the second tank portion 72 in the up-down direction, and an upper surface wall 74b of the coupling portion 74 is set to be lower than the upper surface wall 72a of the second tank portion 72. The upper surface wall 74b of the coupling portion 74 has a downward concave shape. At the concave upper surface wall 74b, the jet water conduit 28 is arranged.

Next, with reference to FIG. 10, a positional relationship between the toilet body and the tank device of the flush toilet according to the first embodiment of the present invention will be described in detail.

FIG. 10 is a top view illustrating a positional relationship between the toilet body and the tank device of the flush toilet according to the first embodiment of the present invention. In FIG. 10, the toilet body 2 is illustrated with dashed double-dotted lines.

As illustrated in FIG. 10, the water storage tank 42 of the tank device 4 is disposed inside the toilet body 2 to be located below the bowl 12. The first tank portion 70 of the water storage tank 42 is arranged on the right side of the central line CL at the center of the toilet body 2 in the left-right direction, and the second tank portion 72 is arranged on the left side of the central line CL. The coupling portion 74 of the water storage tank 42 is arranged close to the central line CL. The first tank portion 70 and the second tank portion 72 are arranged with the drain trap pipeline 14 interposed therebetween. In addition, the coupling portion 74 is arranged directly under the jet water ejection port 26 and the jet water conduit 28. At the concave upper surface wall 74b of the coupling portion 74, the jet water conduit 28 is arranged.

The front end of the water storage tank 42 is located close to the center of the bowl 12 of the toilet body 2 in the front-rear direction. The left and right ends of the water storage tank 42 are located on the outer side of the left and right ends of the bowl 12, respectively. The rear end of the first tank portion 70 of the water storage tank 42 is located behind the rear end of the bowl 12, and the rear end of the second tank portion 72 is located in front of the rear end of the bowl 12. Consequently, a space in which the functional devices such as the pump device 34 and the like can be disposed is formed in the rear region A behind the second tank portion 72.

Next, with reference to FIG. 11, a positional relationship between the tank device and the functional devices of the flush toilet 1 according to the first embodiment of the present invention will be described in detail.

FIG. 11 is a side sectional view illustrating an arrangement of the functional devices of the flush toilet according to the first embodiment of the present invention.

As illustrated in FIG. 11, the pump device 34, the switch valve device 36, the control device 38, and the like, which are the functional devices, are disposed in the rear region A behind the second tank portion 72 of the water storage tank 42. The pump device 34, the control device 38, and the switch valve device 36 are disposed substantially in a line in the up-down direction. In addition, the upstream connection pipe 54 connecting the tank device 4 and the pump device 34 to each other, the downstream connection pipe 56 connecting the pump device 34 and the switch valve device 36 to each other, the rim water supply pipe 58 connecting the switch valve device 36 and the rim water conduit 24 to each other, and the jet water supply pipe 60 connecting the switch valve device 36 and the jet water conduit 28 to each other are disposed in the rear region A behind the second tank portion 72.

The pump device 34 is disposed near the rear surface wall 72b of the second tank portion 72. The pump device 34 is disposed to be at approximately the same height as the second tank portion 72. The outlet 72d of the outflow pipeline 72c of the second tank portion 72 is arranged to face an inflow port 34a of the pump device 34 so as to be at approximately the same height as the inflow port 34a of the pump device 34. Consequently, the upstream connection pipe 54 connecting the tank device 4 and the pump device 34 to each other can be formed in a linear form and can be compact.

The control device 38 is fixed to an upper surface of the pump device 34, and the switch valve device 36 is fixed to an upper surface of the control device 38. The downstream connection pipe 56 connecting the pump device 34 and the switch valve device 36 to each other is disposed near the control device 38 so as to be parallel to the control device 38. The pump device 34, the control device 38, and the switch valve device 36 are disposed to overlap each other at least partially in top view. In top view, the switch valve device 36 is disposed on the inner side with respect to the outer peripheral edge of the pump device 34 and the outer peripheral edge of the control device 38. In top view, the downstream connection pipe 56 is disposed on the inner side with respect to the outer peripheral edge of the pump device 34.

Hereinafter, effects of the flush toilet 1 according to the first embodiment described above will be described.

First, according to the flush toilet 1 of the embodiment of the present invention, it is possible to accommodate the functional devices in the rear region A behind the second tank portion 72 and possible to compactly accommodate the tank device 4 and the functional devices in the space S inside the toilet body 2 due to the configuration in which the tank device 4 includes the first tank portion 70 and the second tank portion 72 that are arranged on one side and the other side, respectively, with respect to the center of the toilet body 2 in the left-right direction in top view and in which the length of the second tank portion 72 in the front-rear direction is set to be less than or equal to half the length of the first tank portion 70 in the front-rear direction. Consequently, it is possible to accommodate the tank device 4 inside the toilet body 2 while ensuring the capacity of the tank device 4.

In addition, according to the flush toilet 1 of the embodiment of the present invention, it is possible to freely design the shape of the skirt 16 in front of the toilet body 2, compared with when the coupling portion 74 is disposed in front of the bowl 12, due to the configuration in which the tank device 4 includes the coupling portion 74 coupling the first tank portion 70 and the second tank portion 72 to each other and in which the coupling portion 74 is arranged at the center of the bowl 12 in the front-rear direction in top view.

Further, according to the flush toilet 1 of the embodiment of the present invention, it is possible to avoid interference of the tank device 4 with the jet water conduit 28 due to the configuration in which there are included the jet water ejection port 26 arranged at a lower portion of the bowl 12 and through which flush water is ejected toward the inlet 14a of the drain trap pipeline 14 and the jet water conduit 28 along which flush water is supplied to the jet water ejection port 26, in which the upper surface wall 74b of the coupling portion 74 has a concave shape, and in which the jet water conduit 28 is arranged at the upper surface wall 74b having the concave shape.

In addition, according to the flush toilet 1 of the embodiment of the present invention, it is possible to reduce a space in which air accumulates inside the second tank portion 72 and make the tank device 4 compact due to the configuration in which the upper surface wall 72a of the second tank portion 72 is set to be lower than the upper surface wall 70c of the first tank portion 70.

Further, according to the flush toilet 1 of the embodiment of the present invention, it is possible, even when the tank device 4 is made compact, to store a large amount of flush water due to the configuration in which the water-stop water level WL1 in the first tank portion 70 is set to be higher than the water-stop water level WL3 in the second tank portion 72.

In addition, according to the flush toilet 1 of the embodiment of the present invention, it is possible to accommodate the tank device 4 and the pump device 34 compactly in the space S inside the toilet body 2 due to the configuration in which a functional device is the pump device 34 that delivers the flush water, which is stored in the tank device 4, under pressure to the toilet body 2.

Further, according to the flush toilet 1 of the embodiment of the present invention, it is possible to accommodate the tank device 4, the pump device 34, and the jet water supply pipe 60 compactly in the space S inside the toilet body 2 due to the configuration in which there are included the jet water ejection port 26 arranged at a lower portion of the bowl 12 and through which flush water is ejected toward the inlet 14a of the drain trap pipeline 14, the jet water conduit 28 along which flush water is supplied to the jet water ejection port 26, and the jet water supply pipe 60 connecting the jet water conduit 28 and the pump device 34 to each other and in which the pump device 34 and the jet water supply pipe 60 are accommodated in the space S that is inside the toilet body 2 and that is located behind the second tank portion 72.

In addition, according to the flush toilet 1 of the embodiment of the present invention, it is possible to accommodate the tank device 4, the pump device 34, and the rim water supply pipe 58 compactly in the space S inside the toilet body 2 due to the configuration in which there are included the rim water ejection port 22 arranged at the rim portion 20 of the bowl 12 and through which flush water is ejected, the rim water conduit 24 along which flush water is supplied to the rim water ejection port 22, and the rim water supply pipe 58 connecting the rim water conduit 24 and the pump device 34 to each other and in which the pump device 34 and the rim water supply pipe 58 are accommodated in the space S that is inside the toilet body 2 and that is located behind the second tank portion 72.

Further, according to the flush toilet 1 of the embodiment of the present invention, it is possible to accommodate the tank device 4 and the pump device 34 compactly in the space S inside the toilet body 2 due to the configuration in which the pump device 34 is disposed near the second tank portion 72.

In addition, according to the flush toilet 1 of the embodiment of the present invention, it is possible to compactly connect the tank device 4 and the pump device 34 to each other due to the configuration in which the second tank portion 72 is provided with the outflow pipeline 72c along which the flush water stored in the tank device 4 flows out and in which the outlet 72d of the outflow pipeline 72c is arranged to face the inflow port 34a of the pump device 34.

Further, according to the flush toilet 1 of the embodiment of the present invention, it is possible to make the tank device 4 compact due to the configuration in which the inlet of the outflow pipeline of the second tank portion 72 is open downward and can lower the dead water levels WL2 and WL4 of the flush water inside the tank device 4.

In addition, according to the flush toilet 1 of the embodiment of the present invention, it is possible to increase the water-level rising speed inside the sectional-area decreasing portion 70b and cause the float switch 48 to operate and possible to improve accuracy in detection of the water level by the float switch 48 due to the configuration in which the tank device 4 includes the sectional-area decreasing portion 70b where the horizontal cross-sectional area of the tank device 4 decreases toward an upper portion of the tank device 4 and the float switch 48 that detects the water level of the flush water stored in the tank device 4 and in which the float switch 48 is disposed at the sectional-area decreasing portion 70b.

Next, with reference to FIG. 12 and FIG. 13, a flush toilet 100 according to a second embodiment of the present invention will be described. Except for the shape of the water storage tank, the basic configuration is similar to that of the flush toilet 1 according to the first embodiment of the present invention described above. Hereinafter, only differences from the flush toilet 1 according to the first embodiment will be described, and description of similar configurations, operations, and effects will be omitted.

FIG. 12 is a left perspective view of a tank device of the flush toilet according to the second embodiment of the present invention as viewed from above obliquely, and FIG. 13 is a top view illustrating a positional relationship between a toilet body and a tank device of the flush toilet according to the second embodiment of the present invention. In FIG. 13, a toilet body 102 is illustrated with dashed double-dotted lines.

As illustrated in FIG. 12 and FIG. 13, a water storage tank 142 of a tank device 104 has a J-shape in top view and is formed to be left-right asymmetric with respect to the central line CL at the center of the toilet body 102 in the left-right direction. The water storage tank 142 includes a first tank portion 170 arranged on the right side with respect to the central line CL, a second tank portion 172 arranged on the left side with respect to the central line CL, and a coupling portion 174 coupling the first tank portion 170 and the second tank portion 172 to each other. The length of the coupling portion 174 in the front-rear direction is set to be smaller than the length of the second tank portion 172 in the front-rear direction.

According to the flush toilet of the second embodiment of the present invention, it is possible to make the tank device 104 compact due to the configuration in which the length of the coupling portion 174, which couples the first tank portion 170 and the second tank portion 172 to each other, in the front-rear direction is set to be smaller than the length of the second tank portion 172 in the front-rear direction.

Not limited to the above-described embodiments of the present invention, various changes and modification are available within the scope of the technical concept described in the claims.