JP7714165B2 - Flush water tank device and flush toilet device equipped with same - Google Patents

Description

The present invention relates to a flush water tank device, and in particular to a flush water tank device that supplies flush water to a flush toilet, and a flush toilet device equipped with the same.

Patent Document 1 discloses a flush toilet. This flush toilet is designed to discharge jet flush water from a jet outlet located at the bottom of the bowl, and rim flush water from a rim water outlet located at the top end of the bowl. In this flush toilet, flush water supplied from the stop valve is alternately switched between the low tank side flow path and the bowl side flow path by a water supply branch fitting. Jet flush water utilizes water stored in the low tank from the low tank side flow path. Furthermore, rim flush water utilizes water supplied from the bowl side flow path.

Japanese Patent Application Laid-Open No. 2002-61252

However, in a flush toilet such as that shown in Patent Document 1, it is not possible to simultaneously supply water from the water supply branch fitting to the low tank side flow path and the bowl side flow path. If an attempt were made to simultaneously supply water to the low tank side flow path and the bowl side flow path, the required flow rates and water pressures for the low tank side flow path after the water supply branch fitting and the bowl side flow path would be different, which could lead to flush water flowing unevenly into one of the flow paths, causing problems such as uneven flow of flush water and turbulence.

The present invention has been made to solve the problems and issues of the prior art described above, and aims to provide a flush water tank device that can prevent the flow of flush water from becoming biased toward one of the flow paths at the flow path branch point of the water supply device, and a flush toilet device equipped with the same.

In order to solve the above-mentioned problems, one embodiment of the present invention is a flush water tank device that supplies flush water to a flush toilet, comprising: a water storage tank that stores flush water to be supplied to the flush toilet and is formed with a drain outlet for discharging the stored flush water into the flush toilet; and a water supply device that supplies flush water from a water supply source, the water supply device having a flow path branching section that branches a flow path toward a flush toilet-side flow path that supplies flush water directly to the flush toilet, and a tank-side flow path that supplies water to the storage tank, the flow path branching section of the water supply device comprising a pre-branching flow path connected to a water supply source-side flow path extending from the water supply source, a first branching flow path connected to the flush toilet-side flow path, and a second branching flow path connected to the tank-side flow path, and the central axis of a first specific flow path portion extending in a specific direction in the first branching flow path of the flow path branching section is located at a position offset from the central axis of a downstream end portion extending in the specific direction in the pre-branching flow path.
According to one embodiment of the present invention configured as described above, the flow rate per unit time of flush water supplied through the first branch flow path, which directly supplies flush water to the flush toilet, may be greater than the flow rate per unit time of flush water supplied through the second branch flow path, which supplies water to the water storage tank. Here, the central axis of the first specific flow path portion extending in a specific direction in the first branch flow path of the flow path branching portion is positioned at a position offset from the central axis of the downstream end portion of the pre-branch flow path, which also extends in the specific direction. This makes it difficult for the flow of flush water in a specific direction supplied from the pre-branch flow path to flow into the first specific flow path portion of the first branch flow path while maintaining its flow direction. This prevents branched flush water from flowing unevenly into the first branch flow path, which has a relatively higher flow rate, out of the first and second branch flow paths. This prevents the flow of flush water from being biased toward one of the flow paths at the flow path branching portion of the water supply device, improving the water supply performance from a water supply device equipped with a flow path branching portion.

In one embodiment of the present invention, the central axis of the downstream end portion of the pre-branch flow path is preferably closer to the central axis of the second specific flow path portion extending in the specific direction in the second branch flow path than to the central axis of the first specific flow path portion of the first branch flow path.
According to one embodiment of the present invention configured as described above, the central axis of the downstream end portion of the pre-branch flow path is closer to the central axis of the second specific flow path portion extending in the specific direction in the second branch flow path than to the central axis of the first specific flow path portion of the first branch flow path. This makes it easier for the flow of flush water in the specific direction from the pre-branch flow path to be supplied to the second specific flow path portion of the second branch flow path than to the first specific flow path portion of the first branch flow path, making it easier to supply flush water to the second branch flow path. This further reduces the occurrence of a situation in which branched flush water flows disproportionately into the first branch flow path, which has a relatively higher flow rate, out of the first and second branch flow paths.

In one embodiment of the present invention, the angle formed between the central axis of the downstream end portion of the pre-branch flow path and the central axis of the inlet portion of the first branch flow path is preferably larger than the angle formed between the central axis of the downstream end portion of the pre-branch flow path and the central axis of the inlet portion of the second branch flow path.
According to one embodiment of the present invention configured as described above, the angle formed between the central axis of the downstream end portion of the pre-branch flow channel and the central axis of the inlet portion of the first branch flow channel is larger than the angle formed between the central axis of the downstream end portion of the pre-branch flow channel and the central axis of the inlet portion of the second branch flow channel. This makes it possible to prevent flush water supplied from the pre-branch flow channel from flowing into the first branch flow channel compared to the second branch flow channel. Therefore, it is possible to further prevent the branched flush water from flowing unevenly into the first branch flow channel out of the first and second branch flow channels.

In one embodiment of the present invention, when the central axis of the downstream end portion of the pre-branch flow path is extended, the central axis preferably reaches within the flow path range of the inlet portion of the second branch flow path.
According to one embodiment of the present invention configured as described above, when the central axis of the downstream end portion of the pre-branch flow path is extended, this central axis reaches within the flow path range of the inlet portion of the second branch flow path. This positions the pre-branch flow path toward the second branch flow path, making it easier for flush water supplied from the pre-branch flow path to flow toward the second branch flow path. Therefore, flush water that does not flow into the second branch flow path, which has a relatively small flow rate, can be made to flow into the first branch flow path. This makes it easier for flush water supplied from the pre-branch flow path to be supplied to the second branch flow path, further preventing the branched flush water from flowing unevenly toward the first branch flow path out of the first and second branch flow paths.

In one embodiment of the present invention, the length of the second branch channel is preferably shorter than the length of the first branch channel.
According to one embodiment of the present invention configured as described above, the length of the second branch channel is shorter than the length of the first branch channel, which reduces the pressure loss in the second branch channel compared to the pressure loss in the first branch channel, making it easier to supply wash water to the second branch channel compared to the first branch channel. Therefore, it is possible to further prevent the branched wash water from flowing unevenly into the first branch channel out of the first and second branch channels.

In one embodiment of the present invention, the flow path branching section is preferably configured such that, when the central axis of the downstream end portion of the pre-branch flow path is extended, this central axis extends outside the flow path range of the inlet portion of the first branch flow path.
According to one embodiment of the present invention configured as described above, the flow path branch section is configured so that when the central axis of the downstream end portion of the pre-branch flow path is extended, this central axis extends outside the flow path range of the inlet portion of the first branch flow path. Therefore, flush water supplied from the pre-branch flow path is less likely to flow linearly into the flow path range of the inlet portion of the first branch flow path, and is more likely to collide with a flow path wall within the flow path branch section and remain in the branch flow path. Furthermore, even if the first branch flow path is located closer to the pre-branch flow path than the second branch flow path, flush water is less likely to be directly guided to the first branch flow path. Therefore, flush water is less likely to be directly guided to the first branch flow path and is more likely to be supplied to the second branch flow path. This further reduces the occurrence of branched flush water flowing unevenly toward the first branch flow path out of the first and second branch flow paths.

In one embodiment of the present invention, the flow path branching section preferably includes a guide section on an extension of the central axis of the downstream end portion of the pre-branch flow path that guides cleaning water toward the second branch flow path.
According to one embodiment of the present invention configured as described above, the flow path branching section includes a guide section that guides flush water toward the second branch path, located on an extension of the central axis of the downstream end portion of the pre-branch path. Therefore, flush water is more easily guided toward the second branch path by the guide section, making it easier to guide flush water toward the second branch path. Furthermore, even if the first branch path is formed closer to the pre-branch path than the second branch path, flush water can be more easily guided toward the second branch path. Therefore, flush water is less likely to be directly guided into the first branch path, and is more likely to be supplied to the second branch path. This further reduces the possibility of branched flush water flowing unevenly toward the first branch path out of the first and second branch paths.

Another embodiment of the present invention is a flush toilet device characterized by having a flush water tank device that can prevent the flow of flush water from becoming biased toward either one of the flow paths at the flow path branch point of the water supply device, and the flush toilet that is flushed with flush water supplied from this flush water tank device.

This invention provides a flush water tank device that can prevent the flow of flush water from becoming biased toward one of the flow paths at the flow path branch point of the water supply device, and a flush toilet device equipped with the same.

1 is a perspective view showing the entire flush toilet device according to an embodiment of the present invention. 1 is a full cross-sectional view of a flush toilet apparatus according to an embodiment of the present invention. 1 is a cross-sectional view showing the schematic configuration of a flush water tank apparatus according to an embodiment of the present invention. 1 is a perspective view showing the internal structure of a flush water tank apparatus according to an embodiment of the present invention with the lid of the flush water tank apparatus removed. 1 is a side view showing a flush water tank apparatus according to an embodiment of the present invention with the lid removed. FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. 5. 7 is a cross-sectional view taken along line VII-VII in FIG. 5. 8 is a cross-sectional view taken along line VIII-VIII in FIG. 4. FIG. 10 is a cross-sectional view showing a modified example of a flow path branching portion of a water supply device of a flush water tank assembly according to an embodiment of the present invention. FIG. 10 is a cross-sectional view showing yet another modified example of a flow path branching portion of a water supply device in a flush water tank assembly according to an embodiment of the present invention.

Next, a flush water tank device and a flush toilet device equipped with the same according to one embodiment of the present invention will be described with reference to the accompanying drawings. The embodiments of the present disclosure have been described by way of example, and it will be apparent to those skilled in the art that many modifications, changes, and substitutions can be made within the spirit and scope of the present invention. Therefore, the present invention is not limited to the disclosed embodiments, and various modifications, changes, etc. can be made in form and details without departing from the scope of the claims.
Fig. 1 is a perspective view showing the entire flush toilet apparatus according to one embodiment of the present invention, Fig. 2 is a full cross-sectional view of the flush toilet apparatus according to one embodiment of the present invention, and Fig. 3 is a cross-sectional view showing the schematic configuration of a flush water tank apparatus according to one embodiment of the present invention.

As shown in Figures 1 to 3, a flush toilet apparatus 1 according to one embodiment of the present invention comprises a flush toilet main body 2 and a flush water tank apparatus 4 according to one embodiment of the present invention mounted behind it. The flush water tank apparatus 4 is configured to supply flush water to the flush toilet main body 2. The flush toilet apparatus 1 of this embodiment is configured so that after use, the bowl portion 2a of the flush toilet main body 2 is flushed by operating a lever handle 8 provided on the flush water tank apparatus 4. The flush water tank apparatus 4 of this embodiment is configured to supply flush water stored therein and flush water supplied from the water supply source C to the flush toilet main body 2 based on operation of the lever handle 8, and to flush the bowl portion 2a with this flush water.

As a variant, the present invention can be configured so that the bowl portion 2a is flushed by operating a remote control device (not shown) attached to the wall. Alternatively, the present invention can be configured so that the bowl portion 2a is flushed when a predetermined time has passed after a motion sensor (not shown) attached to the toilet seat detects that the user has left the seat. In this case, the motion sensor (not shown) can be attached to the toilet seat, or in a location where it can detect the user's sitting down, leaving the seat, approaching, leaving, or waving their hand; for example, it can be attached to the flush toilet main body 2 or the flush water tank device 4. The motion sensor (not shown) can also be any device that can detect the user's sitting down, leaving the seat, approaching, leaving, or waving their hand; for example, an infrared sensor or microwave sensor can be used as the motion sensor.

Next, as shown in Figure 2, the flush water tank device 4 comprises a water storage tank 10 which is the flush water tank main body that stores the flush water to be supplied to the flush toilet main body 2, a drain valve 12 for opening and closing a drain outlet 10a provided in this water storage tank 10, a drain valve hydraulic drive unit 14 which is a hydraulic drive mechanism that drives this drain valve 12, and a water supply device 16 which supplies flush water from a water supply source.
Here, the flush water stored in the water storage tank 10 and released when the drain valve 12 is opened is configured to be discharged during toilet flushing from the jet outlet 2b, which is a lower outlet located below the water level W in the bowl 2a of the flush toilet body 2. Furthermore, the flush water supplied from the water supply C and supplied via the toilet body-side water supply valve 19 is configured to be discharged during toilet flushing from the rim outlet 2d, which is an upper outlet located in the rim 2c of the bowl 2a, above the water level W in the bowl 2a.

The water storage tank 10 is a tank configured to store flush water to be supplied to the jet spout 2b of the flush toilet body 2, and has a drain outlet 10a formed at its bottom for discharging the stored flush water into the flush toilet body 2. An overflow pipe 10b is connected to the water storage tank 10 downstream of the drain outlet 10a. This overflow pipe 10b rises vertically from near the drain outlet 10a and extends above the stop-off water level L1 of the flush water stored in the water storage tank 10. Therefore, flush water flowing in from the upper end of the overflow pipe 10b bypasses the drain outlet 10a and flows directly out of the jet spout 2b of the flush toilet body 2.

The drain valve 12 is a direct-acting valve element positioned to open and close the drain outlet 10a. When the drain valve 12 is pulled upward, it opens, and flush water in the water storage tank 10 is discharged into the flush toilet body 2 and ejected from the jet outlet 2b located at the bottom of the bowl portion 2a.

The drain valve hydraulic drive unit 14 is configured to drive the drain valve 12 using the water supply pressure of flush water supplied from the water supply C. Specifically, the drain valve hydraulic drive unit 14 has a cylinder 14a into which water supplied from the tank-side water supply valve 18 flows, a piston 14b slidably disposed within the cylinder 14a, and a rod 15 that protrudes from the bottom end of the cylinder 14a and drives the drain valve 12. Furthermore, a spring 14c is disposed inside the cylinder 14a and biases the piston 14b downward, and a gasket 14e is attached to the piston 14b, ensuring watertightness between the inner wall surface of the cylinder 14a and the piston 14b. A clutch mechanism 22 is provided midway along the rod 15, and this clutch mechanism 22 separates the rod 15 into an upper rod 15a and a lower rod 15b.

The cylinder 14a is a cylindrical member with its axis oriented vertically, and slidably accommodates a piston 14b inside. An inlet pipe 23 is connected to the lower end of the cylinder 14a, allowing water flowing out from the tank-side water supply valve 18 to flow into the cylinder 14a. Therefore, the piston 14b inside the cylinder 14a is pushed up against the biasing force of the spring 14c by the water flowing into the cylinder 14a.

Meanwhile, an outflow hole is provided at the upper end of the cylinder 14a, and the outflow pipe 24 communicates with the interior of the cylinder 14a through this outflow hole. Therefore, when water flows into the cylinder 14a from the inflow pipe 23 connected to the bottom of the cylinder 14a, the piston 14b is pushed upward from the bottom of the cylinder 14a. Then, when the piston 14b is pushed up above the outflow hole, the water that has flowed into the cylinder 14a flows out from the outflow hole through the outflow pipe 24. In other words, when the piston 14b moves upward, the inflow pipe 23 and outflow pipe 24 are connected via the interior of the cylinder 14a.

The outflow pipe 24 also has a branch 24a, and the first downcomer pipe 24b branches downward from this branch 24a and opens downward above the overflow pipe 10b. The second downcomer pipe 24c extends roughly horizontally from the branch 24a and then curves downward, allowing water to flow into the water storage tank 10. Therefore, some of the flush water flowing out of the cylinder 14a flows into the overflow pipe 10b, and the remaining flush water is stored in the water storage tank 10.

The rod 15 is a rod-shaped member connected to the underside of the piston 14b, and extends through a through-hole 14f formed in the bottom surface of the cylinder 14a, protruding downward from within the cylinder 14a. The drain valve 12 is connected to the lower end of the rod 15, and the rod 15 connects the piston 14b and the drain valve 12. Therefore, when water flows into the cylinder 14a and pushes up the piston 14b, the rod 15 connected to the piston 14b lifts the drain valve 12 upward, opening it.

A gap 14d is provided between the rod 15 protruding from below the cylinder 14a and the inner wall of the through-hole 14f of the cylinder 14a, and some of the water that flows into the cylinder 14a flows out through this gap 14d. The water that flows out through the gap 14d flows into the water storage tank 10. Note that because this gap 14d is relatively narrow and has high flow resistance, even when water is flowing out through the gap 14d, the water flowing into the cylinder 14a from the inlet pipe 23 increases the pressure inside the cylinder 14a, pushing up the piston 14b against the biasing force of the spring 14c.

Furthermore, a clutch mechanism 22 is provided midway along the rod 15. The clutch mechanism 22 is configured to separate the rod 15 into an upper rod 15a and a lower rod 15b when the drain valve 12 is lifted a predetermined distance together with the rod 15. When the clutch mechanism 22 is disengaged, the lower rod 15b is no longer linked to the movement of the piston 14b and the upper part of the upper rod 15a, and the lower rod 15b, together with the drain valve 12, descends due to gravity while resisting buoyancy.

A drain valve float mechanism 26 is also provided near the drain valve 12. This drain valve float mechanism 26 is configured to delay the descent of the lower rod 15b and the drain valve 12 and the closing of the drain port 10a after the rod 15 is lifted a predetermined distance and the lower rod 15b is disconnected by the clutch mechanism 22. Specifically, the drain valve float mechanism 26 has a float portion 26a and an engagement portion 26b that interlocks with the float portion 26a.

The engagement portion 26b engages with the lower rod 15b, which has been released by the clutch mechanism 22 and is now descending, preventing the lower rod 15b and drain valve 12 from descending and seating on the drain outlet 10a. Next, the float portion 26a descends as the water level in the water storage tank 10 drops. When the water level in the water storage tank 10 drops to a predetermined level, the float portion 26a rotates the engagement portion 26b, releasing the engagement between the engagement portion 26b and the lower rod 15b. This releases the engagement, allowing the lower rod 15b and drain valve 12 to descend and seat on the drain outlet 10a. This delays the closing of the drain valve 12, allowing the appropriate amount of flush water to be discharged from the drain outlet 10a.

In addition, a vacuum breaker 30 is provided on the inlet pipe 23 connecting the tank-side water supply valve 18 of the water supply device 16 to the drain valve hydraulic drive unit 14. This vacuum breaker 30 allows outside air to be drawn into the inlet pipe 23 when negative pressure occurs on the tank-side water supply valve 18 side, preventing backflow of water from the drain valve hydraulic drive unit 14 side.

Next, the water supply device 16 will be described with reference to FIGS.
Figure 4 is an oblique view showing the internal structure of a flush water tank device according to one embodiment of the present invention with the lid of the flush water tank device removed, Figure 5 is a side view showing a flush water tank device according to one embodiment of the present invention with the lid removed, Figure 6 is a cross-sectional view taken along line VI-VI in Figure 5, Figure 7 is a cross-sectional view taken along line VII-VII in Figure 5, and Figure 8 is a cross-sectional view taken along line VIII-VIII in Figure 4.

As shown in FIG. 3 , the water supply device 16 is installed between a water supply pipe 32 connected to a water main C, an inlet pipe 23, and a rim water supply pipe 25. The water supply device 16 includes a flow path branch 33 that branches the flow path to a tank-side water supply valve 18 and a toilet body-side water supply valve 19, the tank-side water supply valve 18 connected to a second branch flow path 33c of the flow path branch 33, and the toilet body-side water supply valve 19 connected to a first branch flow path 33b of the flow path branch 33. The water supply device 16 is a type of water supply device that includes a flow path branch 33 that branches the flow path to a rim water supply pipe 25 that constitutes a flush toilet-side flow path that directly supplies flush water to the flush toilet body 2, and an inlet pipe 23 that constitutes a tank-side flow path that supplies water to the water storage tank 10. The rim water supply pipe 25 forms a flow path that directly connects the water supply device 16 and the flush toilet body 2 without temporarily storing flush water in the water storage tank 10. The inlet pipe 23 forms a flow path that directly connects the water supply device 16 and the drain valve hydraulic drive unit 14 inside the water storage tank 10. The inlet pipe 23 constitutes a flow path on the drain valve hydraulic drive unit side that supplies water to the drain valve hydraulic drive unit 14. The flow rate per unit time of flush water supplied to the flush toilet body 2 through the rim water supply pipe 25 is set to be greater than the flow rate per unit time of flush water supplied to the water storage tank 10 through the inlet pipe 23.

The tank-side water supply valve 18 is a second on-off valve that controls the water supply to the drain valve hydraulic drive unit 14. The tank-side water supply valve 18 is provided in the second branch flow path 33c and opens and closes the second branch flow path 33c. The tank-side water supply valve 18 controls the water supply to the drain valve hydraulic drive unit 14 based on the operation of the drain control solenoid valve 20, and is configured to control the start and stop of water supply to the water storage tank 10. Next, the tank-side water supply valve 18 comprises a control valve main body 18a, a main valve element 18b disposed within this control valve main body 18a, and a solenoid valve-side pilot valve 18c. Furthermore, the tank-side water supply valve 18 is connected to the drain control solenoid valve 20, which is connected to the solenoid valve-side pilot valve 18c.

The drainage control solenoid valve 20 is configured to move the solenoid valve-side pilot valve 18c built into the tank-side water supply valve 18 and open or close the pilot valve port (not shown) based on a signal sent from the controller 28. When the pilot valve port (not shown) is opened, the pressure in the pressure chamber provided in the control valve main body 18a decreases, opening the main valve element 18b of the tank-side water supply valve 18. When the pilot valve port (not shown) is closed, the pressure in the pressure chamber increases, closing the main valve element 18b. As a result, the main valve element 18b of the tank-side water supply valve 18 opens or closes based on the operation of the drainage control solenoid valve 20, controlling the start and stop of water supply to the drainage valve hydraulic drive unit 14. In this embodiment, the drainage control solenoid valve 20 is a bistable latching solenoid. When energized, the solenoid valve-side pilot valve 18c moves, and this state is maintained even when energization is stopped. With this type of solenoid valve, when current is applied again in the opposite direction, the solenoid valve side pilot valve 18c can be returned to its original position.

The flush water tank device 4 also includes a float switch 34 mounted on the wall of the water storage tank 10. The float switch 34 functions as a water level sensor that detects the water level. The float switch 34 is electrically connected to the controller 28. When the water level in the water storage tank 10 rises to the stop water level L1, the float switch 34 notifies the controller 28 that the water level has reached the stop water level L1. When the water level in the water storage tank 10 drops below the stop water level L1, the float switch 34 notifies the controller 28 that the water level has dropped from the stop water level L1 to below the stop water level L1. When the float switch 34 detects that the water level has reached the stop water level L1, the controller 28 activates the solenoid valve-side pilot valve 18c via the drain control solenoid valve 20, closes the pilot valve port (not shown), closes the main valve body 18b, and stops the water supply to the water storage tank 10.

When the flush water tank device 4 is in standby mode, the water storage tank 10 is at the stop water level L1, and in this state, the pilot valve port (not shown), which is opened and closed by the solenoid valve-side pilot valve 18c, is closed. Therefore, during flushing, the solenoid valve-side pilot valve 18c is moved based on the operation of the drainage control solenoid valve 20, thereby opening the pilot valve port (not shown) and opening the main valve body 18b of the tank-side water supply valve 18. Specifically, the controller 28 receives a signal from the lever handle 8, and then sends an electrical signal to the drainage control solenoid valve 20, activating it and opening the tank-side water supply valve 18.

That is, the tank-side water supply valve 18 controls the supply and stop of supplied flush water to the drain valve hydraulic drive unit 14 based on instruction signals from the controller 28, which is the control unit. In this embodiment, the entire amount of flush water flowing out from the tank-side water supply valve 18 is supplied to the drain valve hydraulic drive unit 14 through the inlet pipe 23. A portion of the flush water supplied to the drain valve hydraulic drive unit 14 flows out through the gap 14d between the inner wall of the through-hole 14f of the cylinder 14a and the rod 15, and flows into the water storage tank 10. In addition, most of the water supplied to the drain valve hydraulic drive unit 14 flows out of the cylinder 14a through the outlet pipe 24 and flows into the overflow pipe 10b and the water storage tank 10, as described above.

The toilet body-side water supply valve 19 is a first on-off valve that supplies flush water from the water main C directly to the flush toilet body 2. The toilet body-side water supply valve 19 is configured to allow water supplied from the first branch flow path 33b to flow into the rim water supply pipe 25. The rim water supply pipe 25 extends outside the water storage tank 10 and communicates with the rim water outlet 2d of the flush toilet body 2 (not shown in Figure 3). Flush water that flows into the rim water supply pipe 25 is discharged from the rim water outlet 2d as rim flush water for cleaning the bowl section 2a. A vacuum breaker 31 is also provided midway along the rim water supply pipe 25. This prevents water from flowing back from the flush toilet body 2 to the toilet body-side water supply valve 19 when negative pressure occurs on the toilet body-side water supply valve 19 side.

The toilet body-side water supply valve 19 comprises a water supply valve main body 19a, a main valve element 19b disposed within the water supply valve main body 19a, and a solenoid valve pilot valve 19c. A water supply control solenoid valve 21 is connected to the toilet body-side water supply valve 19, and the solenoid valve pilot valve 19c is moved by the water supply control solenoid valve 21. Specifically, the solenoid valve pilot valve 19c controls the pressure within a pressure chamber within the water supply valve main body 19a by opening and closing a pilot valve port (not shown) provided in the water supply valve main body 19a. When the pilot valve port (not shown) is opened, the pressure within the pressure chamber within the water supply valve main body 19a decreases, opening the main valve element 19b of the toilet body-side water supply valve 19. When the pilot valve port (not shown) is closed, the pressure within the pressure chamber increases, closing the main valve element 19b. As a result, the main valve body 19b of the toilet body water supply valve 19 is opened and closed based on the operation of the water supply control solenoid valve 21, controlling the start and stop of water supply to the flush toilet body 2.

Meanwhile, flush water supplied from water supply C is supplied to the tank-side water supply valve 18 or the toilet body-side water supply valve 19 via the stop valve 32a, constant flow valve 32b, and flow path branch. The stop valve 32a is located outside the water storage tank 10, and the constant flow valve 32b is connected downstream of it inside the water storage tank 10. A flow path branch 33 is provided downstream of the constant flow valve 32b.

The stop valve 32a is provided to stop the supply of water to the flush water tank device 4 during maintenance, etc., and is normally left open. The constant flow valve 32b is provided to allow water supplied from the water supply C to flow into the water supply device 16 at a predetermined flow rate, and is configured to supply a constant flow rate of water to the water supply device 16 regardless of the installation environment of the flush toilet device 1.

The flow path branch section 33 is formed to branch the flow path toward the rim water supply pipe 25, which constitutes the flush toilet-side flow path that supplies flush water directly to the flush toilet main body 2, and the inlet pipe 23, which constitutes the tank-side flow path that supplies water to the water storage tank 10. The flow path branch section 33 comprises a pre-branch flow path 33a that connects to the water supply source-side flow path extending from the water supply source, a first branch flow path 33b that connects to the rim water supply pipe 25 that constitutes the flush toilet-side flow path, and a second branch flow path 33c that connects to the inlet pipe 23 that constitutes the tank-side flow path. The second branch flow path 33c is connected to the drain valve hydraulic driver 14 via the inlet pipe 23, while the first branch flow path 33b is open to the atmosphere on the flush toilet main body 2 side via the rim water supply pipe 25. Therefore, the pressure of the flush water in the second branch flow path 33c is often higher than the pressure of the flush water in the first branch flow path 33b.

One end of the first branch flow path 33b is connected to the toilet body water supply valve 19 and is further connected to the rim water supply pipe 25 via the toilet body water supply valve 19. The first branch flow path 33b is a piping-like flow path formed within the water supply device 16. The first branch flow path 33b initially extends horizontally from the downstream end of the pre-branch flow path 33a, then bends upward and extends vertically. The central axis B1 of the first branch flow path 33b of the flow path branch section 33 is positioned at a position offset from the central axis B2 of the pre-branch flow path 33a. The angle formed by the central axis B1 of the first branch flow path 33b and the central axis B2 of the pre-branch flow path 33a is 90°. The central axis B2 of the branch portion of the pre-branch flow path 33a and the central axis B3 of the inlet portion of the second specific flow path portion 33e are aligned on the same line.

One end of the second branch flow path 33c is connected to the tank-side water supply valve 18, and is further connected to the inlet pipe 23 via the tank-side water supply valve 18. The second branch flow path 33c is a piping-like flow path formed within the water supply device 16. The second branch flow path 33c extends vertically from the downstream end of the pre-branch flow path 33a.

As shown in FIG. 8, when viewed along the specific direction D1, the central axis B2 of the downstream end portion of the pre-branch flow path 33a extending along the specific direction D1 is closer to the central axis B3 of the second specific flow path portion 33e extending in the specific direction D1 in the second branch flow path 33c than to the central axis B4 of the first specific flow path portion 33d extending in the specific direction D1 in the first branch flow path 33b. The specific direction D1 is the specific direction in which the pre-branch flow path 33a extends in the flow path branching portion 33, and is the direction in which the central axis B2 extends. In this embodiment, the specific direction D1 is the vertical direction.

Furthermore, when the central axis B2 of the downstream end portion of the pre-branch flow path 33a is extended, this extended central axis B2 reaches within the flow path range E1 of the inlet portion of the second branch flow path 33c. More specifically, the extended central axis B2 is positioned so as to pass inside the inner diameter of the water passage at the inlet portion (branch portion) of the second branch flow path 33c.

The angle α1 (90° in this embodiment) formed between the central axis B2 of the downstream end of the pre-branch flow channel 33a and the central axis B1 of the inlet of the first branch flow channel 33b is larger than the angle α2 (0° in this embodiment, not shown) formed between the central axis B2 of the downstream end of the pre-branch flow channel 33a and the central axis B3 of the inlet of the second branch flow channel 33c. As a result, the bending angle α2 of the flow path from the pre-branch flow channel 33a to the second branch flow channel 33c is smaller than the bending angle α1 of the flow path from the pre-branch flow channel 33a to the first branch flow channel 33b, making it easier for the flow of flush water supplied from the pre-branch flow channel 33a to flow into the second branch flow channel 33c compared to the first branch flow channel 33b. The angle α2 is set within the range of 0°≦α2≦90°.

The length of the second branch flow path 33c, for example, the length G1 from the inlet of the second branch flow path 33c to the tank-side water supply valve 18, is shorter than the length of the first branch flow path 33b, for example, the length G2 from the inlet of the first branch flow path 33b to the toilet body-side water supply valve 19.

9 shows a modified example of the flow path branch portion 33. In the modified flow path branch portion 33, the positions and shapes of the first branch flow path 33b and the second branch flow path 33c relative to the pre-branch flow path 33a are changed.
The flow path branch section 33 of the modified example includes a pre-branch flow path 33a, a first branch flow path 33b extending upward above the pre-branch flow path 33a at a position offset from the extension line of the pre-branch flow path 33a, and a second branch flow path 33c extending approximately horizontally in the lateral direction from the downstream end of the pre-branch flow path 33a. The flow path branch section 33 is configured such that, when a central axis B2 extending along a specific direction D1 at the downstream end portion of the pre-branch flow path 33a is extended, the central axis B2 extends outside the flow path range E1 at the inlet portion of the first branch flow path 33b. The first branch flow path 33b is formed to extend in the specific direction D1 at a position offset from the central axis B1 of the pre-branch flow path 33a. Therefore, the cleaning water supplied from the pre-branch flow path 33a is less likely to flow linearly into the flow path range E1 at the inlet portion of the first branch flow path 33b, and is more likely to collide with the flow path wall within the flow path branch section 33, for example, the guide section 36 described later, and become stagnant within the flow path branch section 33.

Furthermore, the flow path branch section 33 is provided with a guide section 36 that guides flush water toward the second branch flow path 33c, located on an extension of the central axis B2 that extends along the specific direction D1 of the downstream end portion of the pre-branch flow path 33a. The guide section 36 is formed on an extension of the central axis B2 and forms a wall surface that is perpendicular to the central axis B2. Therefore, as shown by arrow F1, the main flow of flush water flowing in from the pre-branch flow path 33a collides with the opposing guide section 36 and is guided toward the horizontal second branch flow path 33c. This makes it difficult for flush water to be directly guided to the first branch flow path 33b, and makes it easier for flush water to be supplied to the second branch flow path 33c.

Furthermore, Figure 10 shows yet another modified example of the flow path branch section 33. In this modified example of the flow path branch section 33, a first branch flow path 33b and a second branch flow path 33c are formed at a position where the pre-branch flow path 33a branches into two. The flow path branch section 33 of this modified example includes a pre-branch flow path 33a, a first branch flow path 33b that extends upward at a position above the pre-branch flow path 33a and offset to one side from the extension line of the pre-branch flow path 33a, and a second branch flow path 33c that extends upward at a position offset to the other side from the extension line of the pre-branch flow path 33a.

The flow path branch section 33 is configured such that, when a central axis B2 extending along a specific direction D1 at the downstream end portion of the pre-branch flow path 33a is extended, the central axis B2 extends outside the flow path range H1 at the inlet portion of the first branch flow path 33b. The first branch flow path 33b is formed to extend in the specific direction D1 at a position offset from the central axis B2 of the pre-branch flow path 33a. Therefore, it is possible to make it difficult for the flush water supplied from the pre-branch flow path 33a to collide with a flow path wall within the flow path branch section 33 and then flow linearly into the flow path range H1 at the inlet portion of the first branch flow path 33b.
The flow path branch section 33 also includes a guide section 36, located on an extension of the central axis B2 extending along the specific direction D1 at the downstream end of the pre-branch flow path 33a, that guides the inflowing flush water toward the second branch flow path 33c while preventing it from flowing directly into the first branch flow path 33b. The guide section 36 is formed on an extension of the central axis B2 and forms a wall surface perpendicular to the central axis B2. Therefore, as shown by arrow F2, the main flow of flush water flowing in from the pre-branch flow path 33a collides with the opposing guide section 36 and is guided toward the horizontal second branch flow path 33c. This makes it difficult for flush water to be directly guided into the first branch flow path 33b, while making it easier for flush water to be supplied to the second branch flow path 33c.

Returning to this embodiment, the explanation will be continued. The controller 28 incorporates a CPU, memory, interface circuitry, etc., and can control other electrically connected devices based on a predetermined control program, etc. For example, the controller 28 incorporates a circuit board and is configured to control the drain control solenoid valve 20, the water supply control solenoid valve 21, etc., based on the operation of the lever handle 8. The controller 28 is electrically connected to the lever handle 8, the drain control solenoid valve 20, the water supply control solenoid valve 21, the float switch 34, etc., and can send and receive electrical signals between them, allowing each part to be electrically operated.

The controller 28 sends a control signal to the drain control solenoid valve 20, moving the solenoid valve-side pilot valve 18c. When the solenoid valve-side pilot valve 18c opens the pilot valve port (not shown) of the control valve main body 18a, the pressure in the pressure chamber within the control valve main body 18a decreases, moving the main valve body 18b and opening the tank-side water supply valve 18. As a result, flush water supplied from the water supply pipe 32 flows from the tank-side water supply valve 18 to the drain valve hydraulic drive unit 14 and is supplied to the water storage tank 10 via the drain valve hydraulic drive unit 14.

The controller 28 also sends a control signal to the water supply control solenoid valve 21, moving the solenoid valve pilot valve 19c. When the solenoid valve pilot valve 19c opens the pilot valve port (not shown) of the water supply valve main body 19a, the pressure in the pressure chamber within the water supply valve main body 19a decreases, moving the main valve body 19b and opening the toilet body water supply valve 19. As a result, flush water supplied from the water supply pipe 32 flows from the toilet body water supply valve 19 to the rim water supply pipe 25 and is discharged from the rim water outlet 2d of the flush toilet main body 2.

Next, with reference to Figures 3 and 8, the operation of the flush water tank device 4 according to one embodiment of the present invention and the flush toilet device 1 equipped with it will be explained.

First, in the toilet flush standby state as shown in Figure 3, the water level in the water storage tank 10 is at the stop water level L1, and no current is applied to the drain control solenoid valve 20 or the water supply control solenoid valve 21. In this state, the pilot valve port (not shown) opened and closed by the solenoid valve pilot valve 18c is closed. As a result, the main valve body 18b of the tank-side water supply valve 18 is closed. In addition, the pilot valve port (not shown) opened and closed by the solenoid valve pilot valve 19c is also closed, and the main valve body 19b of the toilet body-side water supply valve 19 is also closed.

Next, when the user operates the lever handle 8 (Figure 1), a signal commanding toilet flushing is sent to the controller 28 (Figure 3). Upon receiving the toilet flush command signal, the controller 28 energizes the water supply control solenoid valve 21, opening the solenoid valve pilot valve 19c of the toilet body water supply valve 19. This reduces the pressure in the pressure chamber of the toilet body water supply valve 19, causing the main valve body 19b to lift off its valve seat and open. In this embodiment, a bistable latching solenoid is used as the water supply control solenoid valve 21, so once the solenoid valve pilot valve 19c is opened, it remains open even when power is cut off.

When the toilet body water supply valve 19 is opened, tap water supplied to the toilet body water supply valve 19 from the water supply pipe 32 via the flow path branch 33 and the first branch flow path 33b flows through the toilet body water supply valve 19 into the rim water supply pipe 25. The flush water that flows into the rim water supply pipe 25 is discharged from the rim water outlet 2d (Figure 2) of the flush toilet body 2, and the rim flush water begins to flush the bowl portion 2a.

After energizing the water supply control solenoid valve 21, the controller 28 energizes the drain control solenoid valve 20 after a predetermined time has elapsed, causing the solenoid valve-side pilot valve 18c to unseat from the pilot valve port (not shown). This reduces the pressure in the pressure chamber of the tank-side water supply valve 18, causing the main valve element 18b to unseat from its valve seat and open. That is, after opening the toilet body-side water supply valve 19, the controller 28 opens the tank-side water supply valve 18 while maintaining the toilet body-side water supply valve 19 in its open state. Note that in this embodiment, a bistable latching solenoid is used as the drain control solenoid valve 20, and therefore, once the solenoid valve-side pilot valve 18c is opened, it remains open even when energization is stopped. When the tank-side water supply valve 18 is opened, tap water supplied to the tank-side water supply valve 18 from the water supply pipe 32 via the flow path branch 33 and the second branch flow path 33c flows through the tank-side water supply valve 18 and into the inlet pipe 23.

Flush water that flows into the inlet pipe 23 then flows into the cylinder 14a of the drain valve hydraulic drive unit 14, pushing up the piston 14b. This also pulls up the rod 15 and drain valve 12 connected to the piston 14b, opening the drain outlet 10a. As a result, flush water stored in the water storage tank 10 flows out through the drain outlet 10a and is discharged from the jet outlet 2b (Figure 2) located at the bottom of the bowl portion 2a. The flush water discharged from the jet outlet 2b fills the drain trap pipe 2e extending from the bottom of the bowl portion 2a, inducing a siphon effect. Due to the siphon effect, accumulated water and waste in the bowl portion 2a are discharged through the drain trap pipe 2e. In this way, opening the drain outlet 10a causes flush water to be discharged simultaneously from both the rim outlet 2d and the jet outlet 2b.

As shown in Figure 8, this section describes the state when flush water is simultaneously supplied from the water supply pipe 32 to both the first branch flow path 33b and the second branch flow path 33c at the flow path branch section 33. At this time, the flow rate per unit time of flush water supplied directly by the water supply device 16 through the rim water supply pipe 25 for flushing the flush toilet body 2 is greater than the flow rate per unit time of flush water supplied to the water storage tank 10 through the inlet pipe 23, and the flow rate per unit time of flush water supplied through the first branch flow path 33b is greater than the flow rate per unit time of flush water supplied through the second branch flow path 33c.

At the flow path branch section 33, the flow direction (specific direction D1) of the cleaning water supplied from the pre-branch flow path 33a is offset from the flow direction D2 of the cleaning water flowing into the first branch flow path 33b. This makes it difficult for the cleaning water supplied from the pre-branch flow path 33a to flow linearly into the first branch flow path 33b while maintaining its flow direction (specific direction D1). This prevents the branched cleaning water from flowing unevenly toward the first branch flow path 33b (out of the first and second branch flow paths 33b and 33c). For example, this prevents a flow rate imbalance such as a flow rate greater than the specified flow rate intended for the first branch flow path 33b flowing into the first branch flow path 33b and a flow rate less than the specified flow rate intended for the second branch flow path 33c flowing into the second branch flow path 33c.

Furthermore, the central axis B2 of the downstream end portion of the pre-branch flow path 33a extending along the specific direction D1 is closer to the central axis B3 of the second specific flow path portion 33e extending along the specific direction D1 of the second branch flow path 33c than to the central axis B4 of the first specific flow path portion 33d extending along the specific direction D1 of the first branch flow path 33b. Therefore, flush water supplied from the pre-branch flow path 33a can be more easily supplied to the second specific flow path portion 33e extending along the specific direction D1 of the second branch flow path 33c compared to the first specific flow path portion 33d extending along the specific direction D1 of the first branch flow path 33b, making it easier to supply flush water to the second branch flow path 33c. For example, if a pre-branch flow path 33a extending in a specific direction D1, a first specific flow path portion 33d, and a second specific flow path portion 33e are formed within the water supply device 16, the flow in the pre-branch flow path 33a can be made to flow more easily to the second specific flow path portion 33e, which is closer and extends in the same direction, making it easier to supply flush water to the second branch flow path 33c.

Furthermore, the angle α1 formed between the central axis B2 of the pre-branch flow channel 33a and the central axis B1 of the inlet portion of the first branch flow channel 33b is larger than the angle α2 (not shown) formed between the central axis B2 of the pre-branch flow channel 33a and the central axis B3 of the inlet portion of the second branch flow channel 33c. Therefore, the flow of flushing water supplied from the pre-branch flow channel 33a is more likely to flow into the second branch flow channel 33c than into the first branch flow channel 33b. This makes it less likely that the branched flushing water will flow unevenly into the first branch flow channel 33b, out of the first and second branch flow channels 33b and 33c.

Furthermore, when the central axis B2 of the downstream end portion of the pre-branch flow path 33a is extended, this extended central axis B2 reaches within the flow path range E1 of the inlet portion of the second branch flow path 33c. As a result, the pre-branch flow path 33a is positioned toward the second branch flow path 33c, and the flush water supplied from the pre-branch flow path 33a is first directed toward the second branch flow path 33c, allowing flush water that does not fully flow into the second branch flow path 33c (for example, flush water that does not fully flow in and accumulates at the inlet) to flow toward the first branch flow path 33b. This makes it easier for the flush water supplied from the pre-branch flow path 33a to flow into the second branch flow path 33c, making it less likely that the branched flush water will flow unevenly toward the first branch flow path 33b.

Furthermore, the length G1 of the second branch flow path 33c is shorter than the length G2 of the first branch flow path 33b. This reduces the pressure loss in the second branch flow path 33c compared to the pressure loss in the first branch flow path 33b, making it easier to supply cleaning water to the second branch flow path 33c compared to the first branch flow path 33b. This makes it easier for the branched cleaning water to flow into the second branch flow path 33c out of the first branch flow path 33b and the second branch flow path 33c, making it even less likely that the cleaning water will flow unevenly toward the first branch flow path 33b.

In this way, the cleaning water supplied from the pre-branch flow path 33a can be branched at the flow path branch section 33 into a flow at a predetermined flow rate that flows into the first branch flow path 33b and a flow at a predetermined flow rate that flows into the second branch flow path 33c, even if cleaning water is supplied to two flow paths at the same time.

Next, the operation of the flush water tank device 4 and the like will be explained again, starting from the operation in which the flush water that has flowed into the inlet pipe 23 flows into the drain valve water pressure drive unit 14.
When the piston 14b in the drain valve hydraulic drive unit 14 is pushed up, and as a result, the rod 15 and drain valve 12 are pulled up to a predetermined position, the clutch mechanism 22 separates the lower rod 15b and drain valve 12 from the upper rod 15a. As a result, while the tank-side water supply valve 18 is open, the upper rod 15a remains pushed up together with the piston 14b, while the lower rod 15b and drain valve 12 descend under their own weight. However, the separated lower rod 15b engages with the engaging portion 26b of the drain valve float mechanism 26, preventing the lower rod 15b and drain valve 12 from descending. As a result, the drain port 10a of the water storage tank 10 remains open even after the clutch mechanism 22 is separated, and drainage from the water storage tank 10 continues.

Flush water also flows from the inlet pipe 23 into the cylinder 14a of the drain valve hydraulic drive unit 14, and when the piston 14b is pushed up to the top of the cylinder 14a, the flush water in the cylinder 14a flows out through the outlet pipe 24. Some of the water that flows into the cylinder 14a from the inlet pipe 23 flows out through the gap 14d between the inner wall of the through-hole 14f of the cylinder 14a and the rod 15, and this water flows into the water storage tank 10. Meanwhile, some of the flush water that flows out through the outlet pipe 24 flows into the overflow pipe 10b, and the remaining flush water flows into the water storage tank 10. In other words, some of the flush water that flows out of the drain valve hydraulic drive unit 14 flows into the water storage tank 10, and the remaining flush water that flows into the overflow pipe 10b bypasses the drain valve 12 and flows into the flush toilet body from the jet spout 2b. Furthermore, because the flow rate of flush water flowing into the water storage tank 10 through the outflow pipe 24 is less than the flow rate of flush water discharged from the drain outlet 10a when the drain valve 12 is opened, the water level in the water storage tank 10 drops in this state.

Next, when the flush water in the water storage tank 10 is discharged, causing the water level in the water storage tank 10 to drop, the float switch 34 enters a state where it is not detecting the water level. As a result, the controller 28 controls the drain control solenoid valve 20 to keep the solenoid valve-side pilot valve 18c unseated from the pilot valve port. The tank-side water supply valve 18 remains open.

Next, when the flush water in the water storage tank 10 is discharged from the drain outlet 10a and the water level in the water storage tank 10 drops to a predetermined level, the float portion 26a of the drain valve float mechanism 26 descends, moving the engagement portion 26b. This disengages the lower rod 15b from the engagement portion 26b, and the lower rod 15b and drain valve 12 begin to descend again. Then, after a predetermined time has elapsed, the drain outlet 10a of the water storage tank 10 is closed by the drain valve 12, and the flush water that has flowed out of the drain outlet 10a is stopped from being discharged from the jet spout 2b.

Furthermore, because the tank-side water supply valve 18 remains open even after the drain outlet 10a is closed, water supplied from the water supply pipe 32 flows into the drain valve hydraulic drive unit 14 and out into the outlet pipe 24. A portion of the flush water that flows out of the outlet pipe 24 flows into the overflow pipe 10b through the first downcomer pipe 24b. Therefore, even after the drain outlet 10a is closed, the flush water that flows into the overflow pipe 10b flows into the bowl section 2a at a small flow rate through the jet spout 2b, and this inflowing flush water is used as refill water. In addition, a portion of the remaining flush water that flows out of the outlet pipe 24 flows into the water storage tank 10 through the second downcomer pipe 24c, causing the water level in the water storage tank 10 to rise.

Furthermore, after a predetermined time has elapsed since the start of flushing, the controller 28 sends a control signal to the water supply control solenoid valve 21, closing the solenoid valve pilot valve 19c of the toilet body water supply valve 19. This stops water from being discharged from the rim spout 2d of the flush toilet body 2. After jet spouting has ended, flush water discharged from the rim spout 2d also flows into the bowl section 2a and is used as refill water. Even after the toilet body water supply valve 19 is closed, the tank side water supply valve 18 remains open, and flush water that passes through the drain valve hydraulic drive section 14 and flows from the first downcomer pipe 24b into the overflow pipe 10b is used to refill the bowl section 2a.

Next, when the water level in the water storage tank 10 rises to the predetermined water stop level L1, the float switch 34 detects the water level, and the controller 28 controls the drain control solenoid valve 20 to move the solenoid valve pilot valve 18c and close the pilot valve port. This increases the pressure in the pressure chamber in the control valve main body 18a, closing the main valve body 18b and closing the tank-side water supply valve 18. This stops water supply to the water storage tank 10. Alternatively, the present invention can be configured so that the toilet body-side water supply valve 19 remains open until the tank-side water supply valve 18 is closed, and then closes after the tank-side water supply valve 18 is closed. As another variation, the float switch 34 may not be provided, and the controller 28 may control the drain control solenoid valve 20 to move the solenoid valve-side pilot valve 18c and close the pilot valve port after a predetermined time has elapsed since the start of cleaning in response to the receipt of an operation signal from the lever handle 8. As yet another variation, a mechanical float device may be provided instead of the float switch 34, and the float-side pilot valve may be moved to close or open the pilot valve port by detecting the water level of the mechanical float device.

On the other hand, when the tank-side water supply valve 18 is closed, stopping the water supply to the drain valve hydraulic drive unit 14, the piston 14b of the drain valve hydraulic drive unit 14 is pushed down by the biasing force of the spring 14c. When the upper rod 15a is pushed down along with the piston 14b, the upper rod 15a and lower rod 15b, which had been separated by the clutch mechanism 22, are reconnected. Therefore, the next time a toilet flush is performed, both the upper rod 15a and lower rod 15b are pulled up by the piston 14b. This completes one toilet flush and the flush toilet device returns to its standby state.

In the flush water tank device 4 according to one embodiment of the present invention, the flow rate per unit time of flush water supplied through the first branch flow path 33b, which directly supplies flush water to the flush toilet body 2, may be greater than the flow rate per unit time of flush water supplied through the second branch flow path 33c, which supplies water to the water storage tank 10. Here, the central axis B4 of the first specific flow path portion 33d extending in a specific direction in the first branch flow path 33b of the flow path branch section 33 is positioned offset from the central axis B2 of the downstream end portion extending in a specific direction in the pre-branch flow path 33a. This makes it difficult for the flow of flush water in a specific direction supplied from the pre-branch flow path 33a to flow into the first specific flow path portion 33d of the first branch flow path 33b while maintaining its flow direction. This prevents branched flush water from flowing unevenly toward the first branch flow path 33b, which has a relatively higher flow rate, out of the first branch flow path 33b and the second branch flow path 33c. This prevents the flow of flush water from being biased toward one of the flow paths at the flow path branch 33 of the water supply device 16, improving the water supply performance from the water supply device 16 equipped with the flow path branch 33.

Furthermore, with the flush water tank device 4 according to one embodiment of the present invention, the central axis B2 of the downstream end portion of the pre-branch flow path 33a is closer to the central axis of the second specific flow path portion 33e extending in a specific direction in the second branch flow path 33c than to the central axis B4 of the first specific flow path portion 33d of the first branch flow path 33b. Therefore, the flow of flush water in a specific direction from the pre-branch flow path 33a is more likely to be supplied by the second specific flow path portion 33e of the second branch flow path 33c than by the first specific flow path portion 33d of the first branch flow path 33b, making it easier to supply flush water to the second branch flow path 33c. This further reduces the occurrence of branched flush water flowing unevenly into the first branch flow path 33b, which has a relatively higher flow rate, out of the first branch flow path 33b and the second branch flow path 33c.

Furthermore, with the flush water tank device 4 according to one embodiment of the present invention, the angle α1 formed between the central axis B2 of the downstream end portion of the pre-branch flow path 33a and the central axis B1 of the inlet portion of the first branch flow path 33b is larger than the angle α2 formed between the central axis B2 of the downstream end portion of the pre-branch flow path 33a and the central axis B3 of the inlet portion of the second branch flow path 33c. This makes it possible to prevent flush water supplied from the pre-branch flow path 33a from flowing into the first branch flow path 33b compared to the second branch flow path 33c. This further prevents the branched flush water from flowing unevenly toward the first branch flow path 33b, out of the first and second branch flow paths 33b and 33c.

Furthermore, with the flush water tank device 4 according to one embodiment of the present invention, when the central axis B2 of the downstream end portion of the pre-branch flow path 33a is extended, this central axis B2 reaches within the flow path range E1 of the inlet portion of the second branch flow path 33c. This positions the pre-branch flow path 33a toward the second branch flow path 33c, making it easier for flush water supplied from the pre-branch flow path 33a to flow toward the second branch flow path 33c. This allows flush water that does not flow into the second branch flow path 33c, which has a relatively small flow rate, to flow into the first branch flow path 33b. This makes it easier for flush water supplied from the pre-branch flow path 33a to be supplied to the second branch flow path 33c, further reducing the occurrence of branched flush water flowing unevenly toward the first branch flow path 33b out of the first and second branch flow paths 33b and 33c.

Furthermore, in the flush water tank device 4 according to one embodiment of the present invention, the length G1 of the second branch flow path 33c is shorter than the length G2 of the first branch flow path 33b. This reduces the pressure loss in the second branch flow path 33c compared to the pressure loss in the first branch flow path 33b, making it easier to supply flush water to the second branch flow path 33c compared to the first branch flow path 33b. This further reduces the occurrence of branched flush water flowing unevenly toward the first branch flow path 33b out of the first and second branch flow paths 33b and 33c.

Furthermore, in the flush water tank device 4 according to one embodiment of the present invention, the flow path branch section 33 is configured so that when the central axis B2 of the downstream end portion of the pre-branch flow path 33a is extended, this central axis B2 extends outside the flow path range H1 of the inlet portion of the first branch flow path 33b. Therefore, flush water supplied from the pre-branch flow path 33a is less likely to flow linearly into the flow path range H1 of the inlet portion of the first branch flow path 33b, and is more likely to collide with the flow path wall within the flow path branch section 33 and remain within the branch flow path. Furthermore, even if the first branch flow path 33b is positioned closer to the pre-branch flow path 33a than the second branch flow path 33c, flush water is less likely to be directly guided to the first branch flow path 33b. Therefore, flush water is less likely to be directly guided to the first branch flow path 33b, and is more likely to be supplied to the second branch flow path 33c. This further reduces the occurrence of branched flush water flowing unevenly toward the first branch flow path 33b out of the first and second branch flow paths 33b and 33c.

Furthermore, in the flush water tank device 4 according to one embodiment of the present invention, the flow path branch section 33 is provided with a guide section 36 that guides flush water toward the second branch flow path 33c, located on an extension of the central axis B2 of the downstream end portion of the pre-branch flow path 33a. Therefore, the guide section 36 makes it easier for flush water to be guided toward the second branch flow path 33c, making it easier to guide flush water toward the second branch flow path 33c. Furthermore, even if the first branch flow path 33b is formed closer to the pre-branch flow path 33a than the second branch flow path 33c, flush water can be more easily guided toward the second branch flow path 33c. Therefore, flush water is less likely to be guided directly into the first branch flow path 33b, and is more likely to be supplied to the second branch flow path 33c. This further reduces the possibility of branched flush water flowing unevenly toward the first branch flow path 33b, out of the first and second branch flow paths 33b and 33c.

Furthermore, one embodiment of the present invention is a flush toilet device 1 characterized by having a flush toilet main body 2 and a flush water tank device 4 that can prevent the flow of flush water from becoming biased toward either one of the flow paths at the flow path branch section 33 of the water supply device 16.

1: Flush toilet device 2: Flush toilet main body 4: Flush water tank device 10: Water storage tank 10a: Drain port 16: Water supply device 33: Flow path branch section 33a: Pre-branch flow path 33b: First branch flow path 33c: Second branch flow path 33d: First specific flow path section 33e: Second specific flow path section 36: Guide section

Claims (7)

A flush water tank device that supplies flush water to a flush toilet,
a water storage tank that stores flush water to be supplied to the flush toilet and has a drain outlet formed therein for discharging the stored flush water into the flush toilet;
a water supply device that supplies flush water from a water supply source, the water supply device having a flow path branching section that branches a flow path toward a flush toilet side flow path that supplies flush water directly to the flush toilet, and a tank side flow path that supplies water to the water storage tank;
The flow path branching section of the water supply device includes a pre-branch flow path connected to a water supply source side flow path extending from the water supply source, a first branch flow path connected to the flush toilet side flow path, and a second branch flow path connected to the tank side flow path and having a lower flow rate than the first branch flow path,
the first branch flow path of the flow path branching section includes a first specific flow path portion extending in a direction substantially the same as a specific direction that is a flow path direction at a downstream end portion of the pre-branch flow path, and a central axis of the first specific flow path portion is disposed at a position shifted from the central axis of the downstream end portion of the pre-branch flow path;
A flush water tank device in which the second branch flow path has a second specific flow path portion extending in approximately the same direction as the specific direction, and the central axis of the downstream end portion of the pre-branch flow path is closer to the central axis of the second specific flow path portion of the second branch flow path than the central axis of the first specific flow path portion of the first branch flow path . A flush water tank device as described in claim 1, wherein the angle formed between the center axis of the downstream end portion of the pre-branch flow path and the center axis of the inlet portion of the first branch flow path is larger than the angle formed between the center axis of the downstream end portion of the pre-branch flow path and the center axis of the inlet portion of the second branch flow path. 3. A flush water tank apparatus according to claim 1 or 2 , wherein when the central axis of the downstream end portion of the pre-branch flow path is extended, this central axis reaches within the flow path range of the inlet portion of the second branch flow path. 4. A flush water tank apparatus according to claim 1 , wherein the length of the second branch flow path is shorter than the length of the first branch flow path. A flush water tank device as described in claim 1, wherein the flow path branching portion is configured so that when the central axis of the downstream end portion of the pre-branch flow path is extended, this central axis extends outside the flow path range of the inlet portion of the first branch flow path. 6. A flush water tank device according to claim 5 , wherein the flow path branching section is provided with a guide section on an extension of the central axis of the downstream end portion of the pre-branch flow path that guides flush water toward the second branch flow path. A flush toilet device,
A flush water tank device according to any one of claims 1 to 6 ;
the flush toilet that is flushed with flush water supplied from this flush water tank device;
A flush toilet device comprising: