Flush toilet

Abstract

To provide a flush toilet bowl that can realize high designability with a low and small tank and can distinguish between a float switch failure and insufficient water supply due to water failure without giving unnecessary cost burden.SOLUTION: The flush toilet bowl comprises: a water storage tank that stores washing water used for washing a toilet bowl body; a control part that controls washing operation of the toilet bowl body; a pump that supplies the washing water in the water storage tank to a toilet bowl body; and a single float switch that detects a water level of the washing water stored in the water storage tank. The pump is a DC pump that stops driving when abnormal rotation of the motor is detected. The float switch detects that the water storage tank is full. The control part controls a water supply time for supplying water to the water storage tank and a drainage time for draining the washing water from the water storage tank, and determines failure of the float switch and the insufficient water supply of the water storage tank when an abnormality occurs in the washing operation of the toilet bowl body.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a flush toilet that flushes the toilet body with flush water. [Background technology]

[0002] Conventionally, there are flush toilets that use a pump to supply flush water from a tank to the toilet body to flush the toilet. As shown in Patent Document 1, some such flush toilets are equipped with two float switches: an upper float switch that detects when the water storage tank is full by the water level, and a lower float switch that detects the minimum water level after flush water has been supplied from the tank to the toilet body. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-100574 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, if two float switches are provided in a tank like this, the manufacturing cost will be high, and the water storage space inside the water storage tank will be narrow, which will cause problems such as the tank becoming larger.In addition, since it is necessary to control two float switches, the controller will become larger and there will be restrictions on the shape of the tank in order to secure space for wiring.

[0005] On the other hand, if only one float switch is provided, it is not possible to distinguish between a faulty state in which the output does not change due to the float switch sticking, and a state in which the float switch is normal but the output does not change due to a low water supply to the tank due to a water outage or the like. Therefore, there is a possibility that a case of insufficient water supply to the tank and a faulty float switch will be judged as the same abnormality. If a case of insufficient water supply to the tank due to a water outage or the like is judged as an abnormality in the same way as a faulty float switch, it may cause users to misunderstand and feel anxious that a product abnormality has occurred, even though no abnormality actually occurs, in an environment where there are only a few flush toilets, such as a home flush toilet. In addition, if the flush toilet becomes unusable due to a judgment of an abnormality, it will cause great inconvenience to the user's life.

[0006] To address this issue, a flow sensor is known that can detect a lack of water supply in the tank. However, while this can distinguish between a lack of water supply and a malfunction of the float switch, the need to place a flow sensor inside the tank results in problems such as a worsening of the design due to the larger tank and unnecessary costs for the user.

[0007] The present invention has been made to solve the above problems, and its object is to provide a practical flush toilet that can distinguish between a float switch failure and a lack of water supply in the tank, while realizing high design quality with a low and small tank, which is in high customer demand, and without incurring unnecessary costs. [Means for solving the problem]

[0008] In order to achieve the above object, according to the present invention, there is provided a flush toilet that flushes a toilet body with flush water, comprising a water storage tank that stores flush water used in the flushing operation of the toilet body, a control unit that controls the flushing operation of the toilet body, a pump that supplies flush water in the water storage tank to the toilet body, and a single float switch that detects the water level of flush water stored in the water storage tank, the pump being a DC pump that stops operation when abnormal rotation of a motor is detected, and the float switch The above The control unit detects when the water storage tank is full, and controls the water supply time for supplying water to the water storage tank and the drain time for draining flushing water from the water storage tank.When an abnormality occurs in the flushing operation of the toilet body, the control unit determines whether the float switch has failed or whether the water supply to the water storage tank is insufficient based on the detection of the float switch, whether or not the DC pump motor is rotating abnormally during the drain time, and the water supply time and drain time.

[0009] With this configuration, it is possible to distinguish between float switch failure and insufficient water supply in the tank based on the detection of the float switch and the presence or absence of abnormal rotation of the DC pump motor during the draining time, which prevents users from misunderstanding and feeling anxious that the product is broken, and prevents the trouble of unnecessary repair work. In addition, because the configuration allows for easy abnormality detection with a single float switch, it is possible to avoid unnecessary cost burdens and to prevent deterioration of the design due to the larger size of the tank.

[0010] Preferably, the toilet body comprises a bowl portion for receiving waste, and a rim outlet provided above the bowl portion for ejecting flushing water supplied from the DC pump into the bowl portion, and all flushing water used for the flushing operation of the toilet body is ejected from the rim outlet.

[0011] With this configuration, unlike jet water discharge, rim water discharge does not require a strong water flow, so a DC pump with low torque can be used without difficulty. Furthermore, with rim water discharge, there is no outlet pressure loss due to water or waste, so a stable water flow can be supplied from the pump. This allows for more accurate time control of water supply and drainage, and improves the accuracy of malfunction judgment, preventing users from misunderstanding or worrying that the product is broken, and preventing the hassle of unnecessary repair work.

[0012] Preferably, the control unit is configured to be able to perform a flushing operation of the toilet body even if the float switch is in a malfunction state.

[0013] With this configuration, detailed fault diagnosis for each part is possible, which avoids misunderstandings for the user and prevents the trouble of unnecessary repairs, but when it comes to the toilet, it is more convenient for the user to continue using it as is if it is safe to use even if some of the parts are broken. Even if the float switch breaks down, the water supply to the water tank is time-controlled so that the tank will not overflow. Also, the pump will not rotate abnormally and break down. In this way, even if the float switch breaks down, other configurations can be used to cover for it, so the user can safely flush the toilet.

[0014] Preferably, the control unit is characterized in that when the water supply time to the water tank has elapsed and control is performed to stop the water supply, if the float switch does not detect a full water level, it reserves the right to reserve the float switch a fault judgment.

[0015] If the float switch does not detect full water when the time for supplying water to the water storage tank has elapsed and control is performed to stop the water supply, it may not be possible to determine whether the float switch failed to detect full water or whether the water supply was insufficient due to a water outage or the like. In this case, even if the malfunction determination is withheld, it is possible to prevent the user from misunderstanding or feeling uneasy. On the other hand, if the malfunction is left unattended, there is a risk that the toilet will become unsafe to use if a simultaneous malfunction occurs in another component. However, since the malfunction can be determined by performing toilet flushing after the float switch malfunctions, it is possible to prevent the malfunction from being left unattended and the user can safely perform the toilet flushing operation. Effect of the Invention

[0016] According to the present invention, it is possible to provide a sanitary washing device that has a high design quality, does not cause the user to misunderstand or worry that the product is broken, and does not require the trouble of unnecessary repairs, allowing the user to continue using it with peace of mind. [Brief description of the drawings]

[0017] [Figure 1] 1 is a schematic diagram showing a flush toilet according to one embodiment of the present invention. [Diagram 2] 4 is a time chart showing the flushing operation under normal conditions in a flush toilet according to an embodiment of the present invention. [Diagram 3] 1 is a time chart showing the flushing operation in a flush toilet according to an embodiment of the present invention when the float switch is stuck in the OFF position and in a faulty state. [Figure 4] 4 is a time chart showing the flushing operation when there is a water shortage in the water storage tank in a flush toilet according to an embodiment of the present invention. [Diagram 5] 1 is a table showing abnormality determination conditions for a flush toilet according to an embodiment of the present invention. [Figure 6]1 is a time chart showing the flushing operation in a flush toilet according to an embodiment of the present invention when the float switch is stuck in the ON position and in a faulty state. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] A flush toilet according to one embodiment of the present invention will now be described with reference to the drawings. First, the configuration of a flush toilet according to one embodiment of the present invention will be explained using Figure 1. Figure 1 is a schematic diagram showing a flush toilet according to one embodiment of the present invention.

[0019] As shown in Figure 1, a flush toilet 1 according to one embodiment of the present invention has a toilet body 2 made of ceramic or the like. The flush toilet 1 also has a water storage tank 4 that stores flush water used to flush the toilet body 2, and the water storage tank 4 is connected to a water supply source (not shown) such as a water supply or sewerage system. A float switch 6 is provided inside the water storage tank 4, which can detect whether the water storage tank 4 is full of water.

[0020] The time for which water is supplied from the water supply source to the water storage tank 4, and the time for which flush water is drained from the water storage tank 4 to the toilet body 2 are controlled by the control unit 8. Specifically, when water is supplied to the water storage tank 4, the water supply source side valve 10 is controlled to open. Thereafter, when the float switch 610 detects that the tank is full or after a predetermined water supply time has elapsed, the water supply source side valve 10 is controlled to close, and water supply is stopped.

[0021] Furthermore, when flushing the toilet body 2, flush water drained from the water storage tank 4 is pressurized by the pump 12 and supplied to the toilet body 2. When the flushing operation starts, the control unit 8 performs an operation to open the pump-side valve 14. After that, after a predetermined flushing time has elapsed, control is performed to close the pump-side valve 14, and water supply is stopped.

[0022] The pump 12 is a DC pump equipped with a DC motor, and abnormal rotation of the motor can be detected and stopped by measuring the back electromotive force. In the case of an AC pump, the torque is strong and a strong water flow can be generated, but a separate sensor or special measuring device is required for measuring the back electromotive force. On the other hand, a DC pump can easily measure the back electromotive force at low cost, but the torque is weak and it cannot generate a strong water flow.

[0023] Here, in a flush toilet 1 according to one embodiment of the present invention, flush water discharged from pump 12 is entirely discharged from rim spout 18, which is provided above bowl portion 16 that receives waste, in the toilet body 2. After cleaning bowl portion 16, the discharged flush water flows down into trap 20 and is drained beyond the rising end 22 of trap 20 (wash-down flushing).

[0024] This type of flushing method does not require a jet discharge, which is a strong water flow to seal the trap 20 and cause a siphoning phenomenon, and can flush with only a rim discharge, which is a relatively weak water flow. Therefore, a DC pump 12, which has a weak torque and is less likely to produce a strong water flow like a jet discharge, can be used without any effort. Furthermore, unlike a jet discharge, a rim discharge does not have an outlet pressure loss due to water or waste, so a stable water flow can be supplied from the pump. This allows for more accurate time control of water supply and drainage.

[0025] Next, the normal flushing operation of a flush toilet 1 according to one embodiment of the present invention will be described using Figures 1 and 2. As shown in Figure 2, before the start of normal flushing operation, the water tank 4 is full of water, and the float switch 6 is in a state that detects full water (referred to here as the ON state). At this time, water is not being supplied to the water tank 4, and the pump 12 is not driven.

[0026] When the flushing operation is started, the control unit 8 opens the pump side valve 14, the pump 12 is driven, and flushing water is drained from the water tank 4. At this time, the water tank 4 is no longer full, so the float switch 6 switches from the ON state to a state in which full water is not detected (herein referred to as the OFF state). The control unit 8 also measures the elapsed time from the start of the flushing operation.

[0027] When a predetermined cleaning time has elapsed since the start of the cleaning operation, the control unit 8 stops the operation of the pump 12, closes the pump side valve 14, and ends the cleaning operation. Under normal circumstances, the water tank 4 does not become empty during the cleaning operation, and the pump 12 does not detect abnormal rotation of the motor and stop driving. At the end of the cleaning operation, the water tank 4 is almost empty, so the float switch 6 is in the OFF state. Furthermore, the control unit 8 opens the water supply source side valve 10 and starts supplying water to the water tank 4. The control unit 8 measures the elapsed time from the start of water supply to the water tank 4. Note that in this embodiment, water supply to the water tank 4 is started at the end of the cleaning operation, but water supply to the water tank 4 may be started at any time during or after the end of the cleaning operation.

[0028] When the float switch 6 switches from the OFF state to the ON state, or when a predetermined water supply time has elapsed since the start of water supply to the water tank 4, the control unit 8 closes the water supply source side valve 10 and ends the water supply to the water tank 4.

[0029] Next, the cleaning operation when the float switch 6 is stuck in the OFF state and in a faulty state will be described with reference to Figures 1 to 3. As shown in Figure 3, when the float switch 6 is stuck in the OFF state and in a faulty state, the float switch 6 is in the OFF state before the cleaning operation starts.

[0030] When the flushing operation is started in this state, the control unit 8 opens the pump-side valve 14, drives the pump 12, and drains flush water from the water tank 4, just as in normal flushing operation. The control unit 8 also measures the elapsed time from the start of the flushing operation. Meanwhile, because the float switch 6 is in the OFF state even before the flushing operation starts, the control unit 8 can determine that an abnormality has occurred within the water tank 4.

[0031] Furthermore, although the float switch 6 is in the OFF state at the start of the cleaning operation, the water tank 4 is actually full, so the pump 12 does not detect abnormal rotation and stop during the cleaning operation. Therefore, similar to normal cleaning operations, when a predetermined cleaning time has elapsed since the start of the cleaning operation, the control unit 8 stops driving the pump 12 and closes the pump side valve 14, ending the cleaning operation. Furthermore, the control unit 8 opens the water supply source side valve 10 and starts supplying water to the water tank 4. The control unit 8 measures the elapsed time from the start of water supply to the water tank 4.

[0032] Because the float switch 6 is stuck in the OFF state and in a faulty state, the float switch 6 will not switch from the OFF state to the ON state even if water is supplied to the water tank. Therefore, when a predetermined water supply time has elapsed since the start of water supply to the water tank 4, the control unit 8 closes the water supply source side valve 10 and ends the supply of water to the water tank 4.

[0033] Next, the flushing operation when there is a water shortage in the water tank 4 will be described with reference to Figures 1 to 4. As shown in Figure 4, the water tank 4 is not full before the flushing operation starts, so the float switch 6 is in the OFF state.

[0034] When the flushing operation is started in this state, the control unit 8 opens the pump-side valve 14, drives the pump 12, and drains flush water from the water tank 4, just as in normal flushing operation. The control unit 8 also measures the elapsed time from the start of the flushing operation. Meanwhile, because the float switch 6 is in the OFF state even before the flushing operation starts, the control unit 8 can determine that an abnormality has occurred within the water tank 4.

[0035] If the flushing operation is started when there is insufficient water in the water tank 4, the water tank 4 may become empty before the predetermined flushing time has elapsed, as shown in Fig. 4. In this case, the pump 12 detects abnormal rotation at the point when the water tank 4 becomes empty and stops driving. The control unit 8 then closes the pump-side valve 14 and opens the water supply source-side valve 10 to start supplying water to the water tank 4. The control unit 8 measures the elapsed time from when water supply to the water tank 4 started.

[0036] When the float switch 6 switches from the OFF state to the ON state, or when a predetermined water supply time has elapsed since the start of water supply to the water tank 4, the control unit 8 closes the water supply source side valve 10 and ends the water supply to the water tank 4.

[0037] 1 to 5, a method for distinguishing between a fault state in which the float switch 6 is stuck in the OFF position and a state in which there is an insufficient water supply in the storage tank 4. Figure 5 is a table showing the conditions for determining an abnormality in a flush toilet 1 according to one embodiment of the present invention.

[0038] 3 to 5, when the float switch 6 is stuck in the OFF position and in a faulty state, or when there is a water shortage in the water tank 4, the float switch 6 is in the OFF position at the start of the flushing operation. Therefore, even if it can be determined that an abnormality has occurred in the water tank 4 at the start of the flushing operation, it is not possible to determine the cause of the abnormality.

[0039] If the pump 12 subsequently detects abnormal rotation due to empty pumping and stops driving before the control unit 8 stops driving the pump 12 after a predetermined cleaning time has elapsed since the start of the cleaning operation, it can be determined that the water tank 4 was not full at the start of the cleaning operation. Therefore, it can be determined that the cause of the abnormality is a lack of water supply in the water tank 4 due to a water outage or the like.

[0040] On the other hand, if the pump 12 does not stop driving when it detects abnormal rotation due to empty pumping, and the control unit 8 stops driving the pump 12 and ends the cleaning operation after a predetermined cleaning time has elapsed since the start of the cleaning operation, it can be determined that the water tank 4 was full at the start of the cleaning operation. In this case, there is a contradiction with the detection of the float switch 6 at the start of the cleaning operation. Therefore, it can be determined that the cause of the abnormality is a malfunction of the float switch 6 stuck in the OFF position.

[0041] With this configuration, it is possible to distinguish between a failure of the float switch 6 and a lack of water supply in the water storage tank 4 based on the detection of the float switch 6 and the presence or absence of abnormal rotation of the motor of the DC pump 7 during the draining time, which prevents the user from misunderstanding and feeling anxious that the product is broken, and prevents the trouble of unnecessary repair work. In addition, because the configuration allows for easy abnormality detection with a single float switch 6, it is possible to avoid unnecessary cost burdens and to prevent deterioration of the design due to the larger size of the tank.

[0042] Next, the cleaning operation when the float switch 6 is stuck in the ON position and in a faulty state, and the method of determining whether the float switch 6 is stuck in the ON position, will be described with reference to Figures 1 to 6. When the float switch 6 is stuck in the ON position and in a faulty state, as shown in Figure 6, the float switch 6 is in the ON position before the cleaning operation starts. Since the float switch 6 is also in the ON position before the start of the cleaning operation under normal circumstances, it is not possible to determine whether there is an abnormality at this point.

[0043] When the flushing operation is started in this state, the control unit 8 opens the pump side valve 14, as in normal flushing operation, drives the pump 12, and drains flush water from the water storage tank 4. The control unit 8 also measures the elapsed time from the start of the flushing operation. Meanwhile, because the float switch 6 is stuck in the ON position, the float switch 6 will not switch to the OFF state even when the flushing operation is started and water is drained from the water storage tank 4.

[0044] As shown in Fig. 6, when a predetermined cleaning time has elapsed from the start of the cleaning operation, the control unit 8 stops driving the pump 12, closes the pump-side valve 14, and ends the cleaning operation. Here, as shown in Fig. 5, under normal circumstances, the water tank 4 is almost empty when the cleaning operation ends, so the float switch 6 should be in the OFF state, but if the float switch 6 is stuck in the ON state, the float switch 6 will still be in the ON state when the cleaning operation ends. Therefore, it can be determined that the float switch 6 is stuck in the ON state, and is in a faulty state.

[0045] In addition, in a normal flushing operation, when the float switch 6 switches from the OFF state to the ON state, or when a predetermined water supply time has elapsed since the start of water supply to the water storage tank 4, the control unit 8 closes the water supply source side valve 10 to end the water supply to the water storage tank 4. However, if the float switch 6 is stuck in the ON state, the float switch 6 does not switch from the OFF state to the ON state, so the float switch 6 cannot determine whether the water storage tank 4 is full. Therefore, if it is determined that the float switch 6 is stuck in the ON state and is in a faulty state at the end of the flushing operation, the detection of the float switch 6 is ignored, and when a predetermined water supply time has elapsed since the start of water supply to the water storage tank 4, the control unit 8 closes the water supply source side valve 10 to end the water supply to the water storage tank 4. With this configuration, water can be supplied to the water storage tank 4 even if the float switch 6 is in a faulty state, so the user can safely perform the flushing operation of the toilet body.

[0046] Furthermore, if a predetermined water supply time has elapsed since the start of water supply to the water storage tank 4 and the control unit 8 has closed the water supply source side valve 10 to end the water supply to the water storage tank 4 and the float switch 6 is in the OFF state, then a contradiction has occurred and the control unit 8 can determine that an abnormality has occurred in the water storage tank 4. However, from this information alone it is not possible to determine whether the cause of the abnormality is a malfunction in which the float switch 6 is stuck in the OFF position, or whether there is a water shortage in the water storage tank 4 due to a water outage or a change in the water supply pressure.

[0047] In this case, the control unit 8 reserves the right to determine whether the float switch 6 is in a malfunctioning state. Even if the determination is reserved, the water supply to the water tank 4 is time-controlled, so the amount of water required for flushing can be stored in the water tank 4 and water will not overflow. In addition, the pump 7 will not rotate abnormally and break down. This prevents the user from having unnecessary misunderstandings or anxiety, and allows the user to safely perform the toilet flushing operation.

[0048] Furthermore, if a decision is withheld and the malfunction is left unattended, there is the risk that the toilet will become unsafe to use if a simultaneous malfunction occurs in another component; however, with a flush toilet 1 according to one embodiment of the present invention, as shown in Figures 1 to 6, a malfunction can be determined by performing a toilet flush after a malfunction in the float switch 6 occurs, so it is possible to prevent the malfunction from being left unattended and the user can safely perform the toilet flushing operation.

[0049] It is not necessary to judge whether there is a malfunction during the next flushing operation after the judgment has been withheld, but it may be judged that there is a malfunction in the float switch 6 if an abnormality is detected consecutively a predetermined number of times or within a predetermined period of time. This configuration can prevent the user from having unnecessary misunderstandings or anxiety, and can prevent the malfunction from being left unattended, allowing the user to safely perform the toilet flushing operation.

[0050] The control unit 8 is not limited to controlling the toilet body, and may also control other functions. [Explanation of symbols]

[0051] 1 flush toilet 2 Toilet bowl body 4. Water tank 6 Float Switch 8. Control Unit 10 Water supply side valve 12 Pump (DC pump) 14 Pump side valve 16 Bowl section 18 Rim Spout 20 Trap 22 Rising Edge

Claims

1. A flush toilet that performs a flushing action to expel waste with flush water, The toilet bowl body, a water storage tank for storing flush water used in the flushing operation of the toilet body; A control unit that controls the flushing operation of the toilet body; a pump that supplies flush water in the water storage tank to the toilet body; a float switch for detecting the water level of flush water stored in the water storage tank; The pump is a direct current pump that stops driving when abnormal rotation of the motor is detected, The float switch detects when the water tank is full, The control unit controls the water supply time for supplying water to the water storage tank and the drain time for draining flush water from the water storage tank, and when an abnormality occurs in the flushing operation of the toilet body, determines whether the float switch has failed or whether the water supply to the water storage tank is insufficient based on detection of the float switch, whether or not the motor of the DC pump is rotating abnormally during the drain time, and the water supply time and drain time.

2. The toilet body includes a bowl portion for receiving waste and a toilet seat provided above the bowl portion. a rim spout that spouts flush water supplied from the DC pump into the bowl portion, 2. The flush toilet according to claim 1, wherein all of the flush water used in the flushing operation of the toilet body is discharged from the rim water discharge port.

3. 3. The flush toilet according to claim 1, wherein the control unit is configured to be able to perform the flushing operation of the toilet body even if the float switch is in a malfunction state.

4. The flush toilet according to claim 3, characterized in that the control unit, when the time for supplying water to the water tank has elapsed and control is performed to stop the water supply, if the float switch does not detect a full water level, reserves the right to determine whether the float switch has failed.

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