Drain plug device

Abstract

This invention provides a drain plug device that operates automatically without communicating with the water heater and prevents the loss of hot water during hot water supply operation. [Solution] The drain plug device 50 allows for manual operation of the drain port 12 based on a pushing operation of the operating unit 53, and automatic operation of the drain port 12 based on the operation of the electric drive unit 60. The hot water detection unit 71 has a sensor that detects the presence or absence of hot water by a change in capacitance, and is mounted on the back side of the tank body 10, below the hot water inlet 11. When the hot water detection unit 71 detects hot water from the hot water inlet 11, the control unit 61 controls the electric drive unit 60 to close the drain port 12.

Description

Technical Field

[0005] , , , , , , , ,

[0006]

[0001] The present invention relates to a drain plug device for opening and closing a drain outlet of a tank body.

Background Art

[0002] As the above drain plug device, a structure that operates automatically in conjunction with a hot water supply operation is known (see Patent Document 1).

[0003] Patent Document 1 describes a drain plug device that opens and closes a drain outlet of a tank body by moving a plug lid up and down. The drain plug device described in Patent Document 1 includes an electric drive unit that operates by being energized to operate the plug lid and can switch the open / closed state of the drain outlet, and a control unit that controls the operation of the electric drive unit. The electric drive unit has a motor and a detection unit that detects the lifting position of the plug lid. When the hot water supply operation of the water heater is executed by operating a remote control arranged in the kitchen or bathroom, the detection unit detects the lifting position of the plug lid. At this time, when it is detected that the plug lid is in the raised position, the drive unit operates according to the instruction of the control unit to lower the plug lid. Then, when it is detected by the detection unit that the plug lid is in the lowered position, the water heater starts filling with water. Thereby, when the hot water supply operation is started, the plug lid automatically descends, and by closing the drain outlet, it is possible to prevent wasteful supply of hot and cold water.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Since the drain plug device described in Patent Document 1 operates in conjunction with the hot water supply operation of the water heater, it is necessary to configure the control unit so that it can communicate with each water heater.

[0006] In view of the above circumstances, the present invention aims to provide a drain plug device that operates automatically without communicating with a water heater and prevents the loss of hot water during hot water supply operation. [Means for solving the problem]

[0007] A drain plug device according to one aspect of the present invention includes a plug cover that opens and closes the drain port of a tank body having a hot water inlet through which hot water from a water heater is supplied, An electrically driven unit that operates when power is applied to operate the plug cover and switch the open / closed state of the drain outlet, A water detection unit is positioned on the back surface of the tank body and detects the presence or absence of water inside the tank body by a change in capacitance, The drain plug device comprises a control unit that controls the operation of the electric drive unit and controls the electric drive unit to close the drain outlet when the hot water detection unit detects hot water from the hot water outlet. [Effects of the Invention]

[0008] This configuration allows the drain plug device to operate automatically without communicating with the water heater. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic diagram showing a drain plug device according to an embodiment. [Figure 2] This is a cross-sectional view showing a drain plug device according to an embodiment. [Figure 3] This is a cross-sectional view showing the drain opening in a state where it has been opened manually. [Figure 4] This is a cross-sectional view showing the state in which the interlocking member has descended due to automatic operation, compared to the state in Figure 3. [Figure 5] This is a cross-sectional view showing the area where the hot water outlet and the hot water detection unit can detect hot water. [Figure 6] This is a flowchart showing the operation of the drain plug device. [Modes for carrying out the invention]

[0010] The drain plug device according to the first aspect of the present invention includes a plug lid that opens and closes a drain port of a tank body having a hot water supply port to which hot water from a water heater is supplied, an electric drive unit that operates by being energized to operate the plug lid and can switch the open / closed state of the drain port, a hot water detection unit that is disposed on the back surface of the tank body and detects the presence or absence of hot water in the tank body based on a change in capacitance, and a control unit that controls the operation of the electric drive unit and controls the electric drive unit to close the drain port when hot water from the hot water supply port is detected by the hot water detection unit. The drain plug device is provided with these components.

[0011] According to this aspect, the drain plug device can operate automatically without communicating with the water heater. In addition, the hot water detection unit is placed on the back surface of the tank body and detects the hot water in the tank body based on the change in capacitance. Therefore, hot water does not directly contact the hot water detection unit. Accordingly, it is possible to prevent damage to members and deterioration of detection accuracy due to adhesion of dirt, generation of rust, etc. caused by contact with hot water. In addition, since the hot water detection unit is disposed on the back surface of the tank body, the hot water detection unit does not interfere with the user's bathing. Furthermore, there is no need to provide the hot water detection unit in the hot water supply path or the like, and the workability is excellent.

[0012] In addition, the drain plug device according to the second aspect of the present invention may, in the first aspect, detect hot water below the hot water supply port by the hot water detection unit.

[0013] According to the second aspect, it is possible to reliably detect hot water from the hot water supply port, and detection leakage and malfunction can be prevented.

[0014] In addition, the drain plug device according to the third aspect of the present invention may, in the first or second aspect, be disposed on the back surface of the tank body by the control unit.

[0015] According to the third aspect, the construction becomes easier compared to being disposed on the bathroom ceiling or the like.

[0016] Further, in the drain plug device according to the fourth aspect of the present invention, in any one of the first to third aspects, the control unit may control the electric drive unit to close the drain port when hot and cold water is detected over a set predetermined time.

[0017] According to the fourth aspect, even if the hot and cold water detection unit detects the hot and cold water used during the cleaning of the tank body, it is possible to prevent the drain port from being accidentally closed.

[0018] Further, in the drain plug device according to the fifth aspect of the present invention, in any one of the first to fourth aspects, when the drain port shifts to the open state, the control unit may invalidate the closing of the drain port for a set predetermined time when the hot and cold water detection unit stops detecting hot and cold water.

[0019] According to the fifth aspect, even if it is detected that the piping is being cleaned after the drainage is completed, it is possible to prevent the drain port from being accidentally closed. Also, when the hot and cold water detection unit momentarily stops detecting hot and cold water due to the shaking of the water surface during drainage or the like and then detects hot and cold water again due to the shaking, it is also possible to prevent the drain port from being accidentally closed.

[0020] Hereinafter, an embodiment of the drain plug device according to the present invention will be described based on the drawings. Note that the embodiments described below show comprehensive or specific examples, and numerical values, shapes, materials, components and their arrangements and positions, connection forms, procedures, etc. are examples and do not limit the present invention. Also, among the configurations in the following embodiments, the configurations not described in the independent claims are configurations that can be appropriately changed as needed.

[0021] (First Embodiment) As shown in FIG. 1, the drain plug device 50 in the first embodiment opens and closes the drain port 12 of the tank body 10 which is a bathtub. The tank body 10 is arranged in the bathroom, and hot and cold water from the water heater 20 is supplied from the hot and cold water supply port 11.

[0022] 〔Tank Body〕 The tank body 10 is a box-shaped body with an open top, and a drain member 30 is attached to its bottom. The tank body 10 also has a hot water inlet 11 on its side for supplying hot water from the water heater 20. The main body 52 and the hot water detection unit 71, which will be described later, are located on the back of the tank body 10. As shown in Figure 2, the drain member 30 is a cylindrical member that is attached to the tank body 10 to form a drain opening 12 on the bottom surface of the tank body 10, and a wire receiver 31 is attached inside. The drain member 30 also has a flange 32 at its upper end and a male threaded portion 33 on its outer circumference, and the tank body 10 is clamped between the flange 32 and the pipe 40 when the male threaded portion 33 is screwed into the pipe 40.

[0023] [Drain plug device] The drain plug device 50 includes a plug cover 51, a main body 52, an operating unit 53, an electric drive unit 60, a control unit 61, a transmission member 80, a hot water detection unit 71, and a position detection unit 72. It enables manual operation of the drain port 12 based on a pushing operation of the operating unit 53, and automatic operation of the drain port 12 based on the operation of the electric drive unit 60. In addition, both manual and automatic operation can switch the open and closed state of the drain port 12. However, in this embodiment, manual operation allows switching from the open state to the closed state and from the closed state to the open state of the drain port 12, while automatic operation only allows switching from the open state to the closed state.

[0024] The main body 52 is a casing whose upper end is attached to the edge of the tank body 10, and is located on the back surface of the tank body 10, except for the portion that is exposed from the surface of the tank body 10. Inside the main body 52 are the operating unit 53, the electric drive unit 60, and the control unit 61, and a transmission member 80 is connected to its end.

[0025] The operating unit 53 includes a switch section 54 that is displaced when pressed by the user, a switch shaft 55 extending downward from the switch section 54, and a locking mechanism 57 that maintains the displacement of the switch section 54 and the raising and lowering position of the stopper cover 51. The operating unit 53 transmits the displacement of the switch section 54 caused by the pressing operation to the stopper cover 51 via a transmission member 80, enabling the opening and closing of the drain port 12 to be switched. Furthermore, the switch shaft 55 has an interlocking member 58 with a rack gear formed on its side, and a protrusion 56 is formed which is pushed by the downward-moving interlocking member 58. A magnet 59 is also embedded in the switch shaft 55.

[0026] The electric drive unit 60 includes a stepping motor 62 whose operation is controlled by a control unit 61, and operates when energized. When the electric drive unit 60 operates, a gear 63 attached to the end of the stepping motor 62 rotates, causing the interlocking member 58 to descend, and the descended interlocking member 58 pushes down the protrusion 56 (Figure 4). At this time, the switch shaft 55 and the switch part 54 descend, and the displacement of the switch part 54 is transmitted to the plug cover 51 through the transmission member 80. After pushing down the protrusion 56, the interlocking member 58 rises as the stepping motor 62 rotates in the reverse direction, returning to the initial position shown in Figure 2. Furthermore, as shown in Figures 2 and 3, the interlocking member 58 does not come into contact with the protrusion 56 in the raised position (initial position), and is designed not to interfere with manual operation. Therefore, the electric drive unit 60 raises the interlocking member 58 after the operation is completed, returning it to the initial position, thereby enabling manual operation after automatic operation.

[0027] The control unit 61 is built into the main unit 52 and controls the operation of the electric drive unit 60 based on information detected by the hot water detection unit 71 and the position detection unit 72. The control unit 61 does not communicate with the water heater 20 and does not receive instructions from the water heater 20.

[0028] The hot and cold water detection unit 71 has a sensor that detects the presence or absence of hot and cold water by a change in capacitance, and as shown in Figure 1, the hot and cold water detection unit 71 is mounted on the back side of the tank body 10 and below the hot water outlet 11. Here, the area 100 in which the hot and cold water detection unit 71 can detect hot and cold water, shown by the dashed line in Figures 1 and 5, includes a position below the hot water outlet 11 through which the hot and cold water supplied from the water heater 20 always passes. Furthermore, the hot and cold water detection unit 71 only needs to be positioned such that the area 100 capable of detecting hot and cold water includes the position through which the hot and cold water supplied from the hot water outlet 11 passes.

[0029] The position detection unit 72 has sensors that detect the raising and lowering position of the plug cover 51 by detecting a magnet 59 embedded in the switch shaft 55, and is provided in two locations, one above and one below, along the displacement direction of the switch unit 54 and the switch shaft 55. The position detection unit 72 determines the raising and lowering position of the plug cover 51 based on which of the upper or lower sensors detects the magnet 59 and transmits this information to the control unit 61. If both sensors detect the magnet 59, or if neither sensor reacts, the control unit 61 determines that there is a malfunction in the device.

[0030] The transmission member 80 is a power transmission member consisting of a resin outer tube and a metal inner wire. The inner wire moves back and forth inside the outer tube in response to manual operation of the operating unit 53 or automatic operation of the electric drive unit 60. The end of the inner wire of the transmission member 80 is connected to the plug cover 51. When the switch unit 54 is lowered, the inner wire moves forward inside the outer tube toward the drain port 12, raising the plug cover 51. Conversely, when the switch unit 54 is raised, the inner wire moves backward inside the outer tube toward the operating unit 53, lowering the plug cover 51.

[0031] (manual operation) Next, we will describe the operation of the drain plug device 50 based on manual operation.

[0032] First, as shown in Figure 2, when the drain port 12 is closed, the stopper cover 51 is in the lowered position and the switch unit 54 is in the raised position. At this time, the packing attached to the stopper cover 51 comes into contact with the periphery of the drain port 12, allowing hot water to be stored in the tank body 10. When the drain port 12 is closed, a pushing operation is applied to the switch part 54, as shown in Figure 3, the switch part 54 and the switch shaft 55 are displaced downward, and this displacement is transmitted by the transmission member 80, causing the stopper cover 51 to rise and the drain port 12 to open. At this time, the gears inside the locking mechanism 57 engage, holding the stopper cover 51 in the raised position. When the switch unit 54 is pressed again, the locking mechanism 57 releases the hold of the stopper cover 51 in the raised position, and the inner wire retracts due to the action of a spring (not shown), the stopper cover 51 descends, and the drain port 12 is closed, returning to the state shown in Figure 2.

[0033] (Automatic operation) Next, the operation of the drain plug device 50 based on automatic operation will be explained using Figures 2 to 4. When the drain outlet 12 is open, the drain plug device 50 is in a standby state (step S1). At this time, the drain plug device 50 is in the same state as when the drain outlet 12 is opened manually, as shown in Figure 3. In the standby state, the hot water detection unit 71 does not detect hot water (hot water detection unit 71 OFF), and the lower sensor of the position detection unit 72 detects the magnet 59. When the bath filling operation starts, hot water is discharged downward from the hot water outlet 11. At this time, the hot water passing through area 100 is detected by the hot water detection unit 71 (hot water detection unit 71 ON) (step S2). Here, when the hot water detection unit 71 detects hot water for a set predetermined time (5 seconds in this embodiment), the control unit 61 determines that hot water supply operation is being performed. Having detected the execution of hot water supply operation, the control unit 61 rotates the gear 63 and, as shown in Figure 4, pushes down the protrusion 56 of the switch shaft 55, which is in a lowered state, again with the interlocking member 58, thereby releasing the lock mechanism 57 from holding the stopper cover 51 in the raised position. When the hold of the stopper cover 51 in the raised position is released, the inner wire retracts due to the action of a spring (not shown), and the stopper cover 51 descends, closing the drain port 12 (step S3). Note that after the interlocking member 58 pushes down the protrusion 56, the gear 63 rotates in the reverse direction, returning the interlocking member 58 to its initial position and transitioning to the state shown in Figure 2, so the interlocking member 58 does not hinder the displacement of the protrusion 56 that has risen due to the action of the spring. Furthermore, the lowered position of the stopper cover 51 is detected when the sensor on the upper side of the position detection unit 72 detects the magnet 59. Furthermore, if no hot or cold water is detected within a predetermined time in step S2, the control unit 61 does not proceed to step S3, but returns to the standby state (step S1). Once the hot water supply operation is complete, the user manually initiates drainage after bathing (step S4). At this time, the lower sensor of the position detection unit 72 detects the magnet 59, causing the valve cover 51 to rise and indicating that the valve is open. Since the interlocking member 58 returns to its initial position in step S3, it does not interfere with the manual operation in step S4. As a result of the manual draining operation described above, the water level in the tank 10 decreases, and the hot and cold water detection unit 71 stops detecting hot and cold water (hot and cold water detection unit 71 OFF) (step S5). At this point, the control unit 61 disables the automatic closing of the drain port 12 for a set predetermined time (60 seconds in this embodiment) (step S6). This prevents the unit from mistakenly switching to a closed state when the hot and cold water detection unit 71 momentarily detects hot and cold water due to fluctuations in the water surface, etc. Furthermore, even if the hot and cold water in the hot water supply pipe is discharged into the tank 10 by the hot water supply pipe cleaning operation after draining is complete, and this hot and cold water is detected by the hot and cold water detection unit 71 (hot and cold water detection unit 71 ON), the drain port 12 will not be mistakenly closed because the closing of the drain port 12 is disabled. After the predetermined time has elapsed, if the water detection unit 71 does not detect water (water detection unit 71 OFF) and the lower sensor of the position detection unit 72 detects the magnet 59, the control unit 61 returns to the standby state (step S1).

[0034] Furthermore, in each step, if the stopper cover 51 is in an unexpected state, the control unit 61 activates the electric drive unit 60 to move the stopper cover 51 to a predetermined state. For example, if, in step S3, the control unit 61 instructs the stopper cover 51 to lower, but the sensor below the position detection unit 72 detects the magnet 59 and determines that the stopper cover 51 is in an upward position, the control unit 61 activates the electric drive unit 60 until it detects that the stopper cover 51 is in the lowered position. If the lowered position of the stopper cover 51 is not detected despite the set number of instructions being given, the control unit 61 stops instructing the electric drive unit 60 and displays an error by sound, light, etc.

[0035] In the automatic operation of the above embodiment, when the electric drive unit 60 switches the cap 51 from the open state to the closed state, the interlocking member 58 returns to its initial position. As a result, even if a manual opening or closing operation is performed after the automatic closing operation, the interlocking member 58 will not interfere with the switch shaft 55.

[0036] [Effects and Effects] As described above, in the drain plug device 50 of this embodiment, the hot water detection unit 71 detects the presence or absence of hot water in the tank body 10. Here, the hot water detection unit 71 is a capacitance sensor that detects the hot water in the tank body 10 by a change in capacitance, and is mounted on the back surface of the tank body 10. Therefore, the hot water does not come into direct contact with the hot water detection unit 71, and damage to the components and a decrease in detection accuracy due to dirt adhering to the hot water or rust occurring can be prevented.

[0037] Furthermore, since the drain plug device 50 operates without communicating with the water heater 20, the drain plug device 50 can continue to be used even if the water heater 20 is replaced with a product from another company. Also, because there is no need to communicate with each water heater, the control unit 61 can be made smaller. In addition, by making the control unit 61 smaller, it becomes possible to place the control unit 61 on the back surface of the tank body 10.

[0038] Furthermore, since the water temperature detection unit 71 is located on the back surface of the bathtub 10, the water temperature detection unit 71 will not interfere with the user's bathing.

[0039] Furthermore, since the hot and cold water detection unit 71 can detect hot and cold water by being attached to the back surface of the tank body 10, there is no need to install sensors in the hot water supply path, etc., resulting in excellent ease of installation.

[0040] The hot water detection unit 71 is positioned below the hot water outlet 11 and is configured so that the hot water supplied from the hot water outlet 11 always passes through the area 100 where the hot water detection unit 71 can detect the water. In this way, hot water operation can be reliably detected.

[0041] Furthermore, when the hot and cold water detection unit 71 detects hot and cold water for a set predetermined period of time, the control unit 61 controls the electric drive unit 60 and sends an instruction to close the drain port 12. In this way, even if the hot and cold water detection unit 71 detects hot and cold water from the shower during cleaning of the tank body 10, it is possible to prevent the drain port 12 from being mistakenly closed.

[0042] Furthermore, after the stopper cover 51 rises and the drain outlet 12 moves to the open state, the control unit 61 disables the automatic closing of the drain outlet 12 for a set predetermined time period once the hot water detection unit 71 stops detecting hot water. This prevents the system from mistakenly switching to standby mode when hot water is discharged into the tank body 10 due to the cleaning operation of the hot water supply piping, or when the hot water detection unit 71 momentarily stops detecting hot water due to fluctuations in the water surface during drainage. Furthermore, this method minimizes the time during which the automatic closing of the drain outlet 12 is disabled. In other words, if the closing of the drain outlet 12 is disabled from the moment it is opened by manual operation, the closing must remain disabled for the entire duration until the drainage of the full bathtub 10 is complete. Therefore, in order to ensure that the closing remains disabled until after the drainage is complete, a large amount of time must be allocated for the closing to be disabled, resulting in a large difference from the actual drainage completion time. In this case, if the bathtub filling operation is started during the time when the closing is disabled, a large amount of hot water may be lost. In contrast, in this embodiment, it is possible to set the disabled time from the point when the water level has dropped to the hot water detection unit 71, thus minimizing the difference from the actual drainage completion time.

[0043] [Differentiation] The above embodiments are merely illustrative, and the drain piping member 12 of the present invention may be modified in various ways without departing from the spirit of the invention. For example, in the first embodiment, in step S2, the control unit 61 determined that hot water supply operation was being performed because the hot water detection unit 71 detected hot water for 5 seconds, but the time required to determine that hot water supply operation is being performed may be changed as appropriate. Similarly, in step S6, the time for disabling the automatic closing of the drain outlet 12 was 60 seconds, but this may also be changed as appropriate.

[0044] Furthermore, the range in which the hot and cold water detection unit 71 can detect hot and cold water, and the detection accuracy, may be changed as appropriate.

[0045] Furthermore, the control in step S6 is not limited to this. For example, even if the hot / cold water detection unit 71 detects hot or cold water after the valve has been opened by manual operation, the open state of the drain outlet 12 may be maintained for a set predetermined time. Alternatively, the system may be configured to transition from step S6 to the standby state after the raised position of the stopper cover 51 is detected, when the hot and cold water detection unit 71 ceases to detect hot and cold water for a set predetermined period of time. In this case, instead of immediately transitioning to the standby state when the hot and cold water detection unit 71 ceases to detect hot and cold water, the system is configured to transition to the standby state when the hot and cold water detection unit 71 ceases to detect hot and cold water for a set predetermined period of time (for example, 5 seconds). This prevents the system from mistakenly transitioning to the standby state when the hot and cold water detection unit 71 momentarily ceases to detect hot and cold water due to fluctuations in the water surface during drainage, etc.

[0046] Furthermore, in the above embodiment, the electric drive unit 60 was only capable of lowering the stopper cover 51, which is in the raised position, and moving the drain port 12 to the closed state. However, it may also be possible to raise the stopper cover 51 and move the drain port 12 to the open state. In this case, a separate switch may be provided to operate the electric drive unit 60.

[0047] Furthermore, in the above embodiment, the hot water detection unit 71 had only one sensor for detecting the presence or absence of hot water. However, the position and number of sensors on which the hot water detection unit 71 is installed, as well as the detection accuracy and range, may be appropriately changed depending on the shape of the hot water outlet 11 and the tank body 10 used. For example, the hot water detection unit 71 may have two sensors, and it may be configured to determine that hot water has been supplied from the hot water outlet 11 only when both sensors detect hot water. [Explanation of symbols]

[0048] 10 Tank body 11 Hot water outlet 12 Drain 20 Water heaters 30 Drainage outlet component 31 Wire receiver 32 Guard section 33 Male screw section 40 Piping 50 Drain plug device 51 Bottle lid 52 Main body 53 Operation section 54 Switch section 55 Switch shaft 56 Convex part 57 Locking mechanism 58 Interlocking member 59 Magnets 60 Electric drive unit 61 Control Unit 62 Stepping motors 63 gears 71 Hot water detection unit 72 Position detection unit 80 Transmission member 100 areas

Claims

1. A stopper cover for opening and closing the drain outlet of a tank body having a hot water inlet through which hot water is supplied from a water heater, An electrically driven unit that operates when power is applied to operate the plug cover and switch the open / closed state of the drain outlet, A water detection unit is positioned on the back surface of the tank body and detects the presence or absence of water inside the tank body by a change in capacitance, A drain plug device comprising: a control unit that controls the operation of the electric drive unit, and when the hot water detection unit detects hot water from the hot water outlet, controls the electric drive unit to close the drain outlet.

2. The drain plug device according to claim 1, characterized in that the hot water detection unit detects hot water below the hot water outlet.

3. The drain plug device according to claim 1, characterized in that the control unit is arranged on the back surface of the tank body.

4. The drain plug device according to claim 1, characterized in that the control unit controls the electric drive unit to close the drain port when hot water is detected for a set predetermined period of time.

5. The drain plug device according to claim 4, characterized in that when the drain port transitions to an open state, the control unit disables the closing of the drain port for a predetermined set period of time when the hot water detection unit no longer detects hot water.

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