JP2012189232A - Bathtub circulation flow passage switching device, and bath hot-water supply system using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bathtub circulation flow passage switching device which inhibits the circulation using only residual water in a bath circulation circuit when a bathtub is empty.SOLUTION: The bathtub circulation flow passage switching device includes: a going flow passage 39 from a heat source unit 3 to a bathtub 2; a return flow passage 40 from the bathtub 2 to the heat source unit 3; a bypass flow passage 41 which bypasses the going flow passage 39 and the return flow passage 40; and a temperature sensitive switching valve 42 which blocks a bypass flow passage 41 side and communicates a heat source unit 3 with a bathtub 2 side of the going flow passage 39 in case a temperature of circulating hot water is high, and blocks the bathtub 2 side of the going flow passage 39 and communicates the bypass flow passage 41 side with the heat source unit 3 side of the going flow passage 39 in case a temperature of circulating hot water is low. Here, an air-water separator 43 is provided on the way of the return flow passage 40, and a heat source unit 3 side of the return flow passage 40 is connected to an upper portion of the air-water separator 43 and a bathtub 2 side of the return flow passage 40 is connected to a lower part of the air-water separator 43, with a prescribed vertical difference from the upper portion of the air-water separator 43, where the heat source unit 3 side of the return flow passage 40 is connected.

Description

  The present invention relates to a bath circulation channel switching device for preventing discharge of cold water remaining in a bath circulation circuit connecting a bath heat exchanger for heating bath water and the bath, and a bath hot water system using the same. It is about.

  In the past, a bathtub circulation device attached to the side wall of a bathtub and a hot water heater are connected by a bath circulation circuit, and hot water in the bathtub is circulated and heated by the bath water heater. Provided with a wax thermo-type bypass valve mechanism that bypasses the circulator for bath when the temperature of hot water circulating in the bath is low, for example, to prevent freezing of the bath circulation circuit in winter etc. When the temperature of the hot water circulating in the bath circulation circuit connecting the bathtub and bath water heater is low when it is circulated to prevent freezing, bypass the circulator for bathtubs and circulate in the vicinity of the bathtub. The bath circulation circuit is prevented from freezing without lowering the temperature of the hot water in the bathtub, and the hot water at the start of the bath reheating operation is bypassed, and only the hot water heated by the bath water heater is used. Bath It was something which is adapted to discharge within (see Patent Document 1).

Japanese Utility Model Laid-Open No. 5-1950 (see FIG. 4)

  However, in this conventional system, when the bath circulation pump of the bath water heater is driven in a state where the bathtub is empty and there is low-temperature residual water in the bath circulation circuit, the bypass valve mechanism closes the bathtub side and opens the bypass side. As a result, the residual water that has flowed into the return flow path to the bath water heater is drawn into the bath water heater side again, and circulation by the residual water is established.

  In general, in a bath water heater, when it is detected that hot water is circulated in the bath circulation circuit, it is determined that there is hot water in the bathtub, so that the remaining water in the bath circulation circuit is empty even though the bathtub is empty. When the circulation is established, the bath water heater cannot recognize that the bathtub is empty.

  In order to solve the above problems, in the present invention, in claim 1, a forward flow path from a heat source unit that heats bath water to a bathtub, a return flow path from the bathtub to the heat source unit, and the forward flow path The bypass channel that short-circuits the return channel, and the hot water that circulates, closes the bypass channel side when the temperature of the circulating hot water is high, connects the heat source machine side and the bathtub side of the forward channel, and circulates the hot water In the case where the temperature is low, the bathtub side of the forward flow path is closed and a temperature-sensitive switching valve that communicates with the bypass flow path side and the heat source machine side of the forward flow path is provided. A water separation unit is provided, the heat source device side of the return channel is connected to the upper portion of the steam / water separation unit, and the bathtub side of the return channel is connected to the heat source device side of the return channel of the steam / water separation unit It was connected to the lower part having a predetermined height difference from the height.

  Moreover, in Claim 2, the end part by the side of the return flow path of the said bypass flow path was connected to the bathtub side rather than the said steam / water separation part of the said water / water separation part or the said return flow path.

  According to a third aspect of the present invention, the temperature-sensitive switching valve includes a temperature-sensitive deformation member that expands and contracts according to the temperature of the flowing hot and cold water, a valve body that is moved by the temperature-sensitive deformation member, and the valve body that is the temperature-sensitive member. The deformable member has a bias spring that biases in the opposite direction.

  According to a fourth aspect of the present invention, the bathtub circulation channel switching device includes: a bathtub circulation port that is attached to a bathtub wall surface and has a discharge port that discharges into the bathtub and a suction port that sucks water in the bathtub; It was assumed to be provided in the vicinity of the tub circulation port.

  Further, in claim 5, as the heat source device, a bath heat exchanger that heats bathtub water, a bath circulation circuit that connects the bathtub and the bath heat exchanger so that the bath water can circulate, and the bath circulation circuit A bath circulation pump provided in the middle and a running water sensor that detects whether hot water is circulating in the bath circulation circuit or not, and the running water sensor discriminates circulation of hot water after driving the bath circulation pump. The bath water heater which made it discriminate | determine whether there is hot water in the said bathtub by doing, Between the said bathtub circulation port and the said bath water heater, and the said bathtub circulation port vicinity. A bath hot water supply system provided with a bath circulation flow path switching device was provided.

  According to the present invention, when low-temperature residual water in the bath circulation circuit flows from the forward flow path of the bathtub circulation flow path switching device while the bathtub is empty, the temperature-sensitive switching valve closes the bathtub side of the forward flow path. Then, the hot water flows into the rising flow path section through the bypass flow path side. Hot water that has flowed into the startup channel is discharged to the bathtub through the return channel, and at the same time, air flows in from the bathtub side of the return channel, and the heat source side of the return channel through the startup channel Air will flow into. Therefore, when the bathtub is empty, the circulation is not established only by the residual water in the bath circulation circuit.

  Moreover, in the bath water heater, it can be surely recognized that the bathtub is empty, and the occurrence of problems due to erroneous detection can be prevented.

Schematic configuration diagram of a bath hot water system of one embodiment of the present invention Flowchart explaining operation during filling operation The figure for explaining the situation at the time of empty judgment when the bathtub is empty Illustration for explaining the initial situation of hot water filling operation Illustration for explaining the situation during hot water operation The figure for explaining the situation at the time of remaining hot water judgment when there is hot water in the bathtub Flowchart explaining the operation during bath chase operation Diagram for explaining the situation in the early days of chasing operation A diagram for explaining the situation during chasing Flow chart explaining operation of freeze prevention operation Schematic configuration diagram of another embodiment of the bathtub circulation channel switching device

Next, a bath hot water supply system according to an embodiment of the present invention will be described with reference to the drawings.
1 is a bathroom, 2 is a bathtub, 3 is a bath water heater installed outside the bathroom 1, 4 is a remote controller of the bath water heater 3 provided in the bathroom 1, and 5 is a curan.

  6 is provided on the wall surface of the bathtub 2 and has a discharge port 6a for discharging to the bathtub 2 and a bathtub circulation port having a suction port 6b for sucking hot water in the bathtub 2, and 7 is connected to the bath water heater 3 and the bathtub circulation port 6. A bath circulation circuit 8 is provided in the middle of the bath circulation circuit 7 and is disposed in the vicinity of the bathtub circulation port 6 in the space behind the bathtub 2 in the bathroom 1 to prevent discharge of cold water from the bath circulation circuit 7 to the bathtub 2. It is a bathtub circulation channel switching device.

<Bath water heater>
The bath water heater 3 will be described. 9 is a hot water storage tank for storing hot water, 10 is a heater for heating hot water in the hot water storage tank 9, 11 is a water supply pipe for supplying city water to the bottom of the hot water storage tank 9, and 12 is a hot water storage tank 9. A hot water discharge pipe for discharging hot water from the top, 13 is a water supply bypass pipe branched from the water supply pipe 11, 14 is a hot water supply mixing valve for mixing hot water from the hot water discharge pipe 12 and water from the water supply bypass pipe 13 at a hot water supply set temperature, 15 A hot water supply pipe that guides hot water mixed by the hot water mixing valve 14 to the currant 5, 16 is a hot water temperature sensor that detects the temperature of the hot water mixed by the hot water mixing valve 14, 17 is a hot water flow rate counter that detects the amount of hot water, and 18 A feed water temperature sensor 19 for detecting the feed water temperature, and a hot water storage temperature sensor 19 for detecting the hot water storage temperature in the hot water storage tank 9.

  20 is a bath heat exchanger that is arranged in the upper part of the hot water storage tank 9 and heats the bath water, 21 is a forward pipe that constitutes the bath circulation circuit 7 and supplies hot water heated by the bath heat exchanger 20 to the bathtub 2, 22 Is a return pipe for constructing the bath circulation circuit 7 and returning the hot water in the bathtub 2 to the bath heat exchanger 20, 23 is a bath circulation pump provided in the return pipe 22, and 24 is a temperature of bath water provided in the return pipe 22 and circulating. The bath temperature sensor 25 detects the water flow sensor 25 is provided in the return pipe 22 to detect whether or not the bath water is circulating, and 26 bypasses the bath heat exchanger 20 between the forward pipe 21 and the return pipe 22. A bath bypass pipe 27 bypasses the hot water from the return pipe 22 to the bath heat exchanger 20 or switches between bypassing the bath heat exchanger 20 and bypassing to the forward pipe 21.

  28 is a hot water pipe that is branched from the hot water supply pipe 15 and connected to the bath circulation circuit 7, 29 is a hot water valve that opens and closes the hot water pipe 28, and 30 is an amount of hot water filled from the hot water pipe 28. A bath flow counter 31 is a check valve for preventing a back flow of hot water from the bathtub 2 side.

  The remote controller 4 includes a display unit 32 for performing necessary displays such as a hot water supply set temperature, a bath set temperature, and a hot water amount, a temperature setting switch 33 for setting the hot water set temperature and the bath set temperature, and a hot water amount. The hot water setting switch 34 for setting, the hot water filling switch 35 for instructing the start of the hot water filling operation of the set hot water amount to the bathtub 2, and the start of the bath reheating operation for heating the bath water to the bath set temperature or higher. A tracking switch 37 for instructing is provided.

  Reference numeral 38 denotes a hot water temperature sensor 16, a hot water flow rate counter 17, a hot water temperature sensor 18, a hot water temperature sensor 19, a bath temperature sensor 24, a running water sensor 25, and a bath flow rate counter 30. The control unit is configured to control the operation of the bath circulation pump 20, the bath three-way valve 27, and the hot water filling valve 29, and to be communicable with the remote controller 4. The control unit 38 has a calculation, comparison, storage function, and clock function. A program for controlling the operation of the bath water heater 3 is stored in advance, and is instructed by the remote controller 4 when hot water is detected by the hot water flow rate counter 17. In addition to performing a hot water supply operation at a hot water supply set temperature, the hot water filling operation is performed according to the operation of the hot water filling switch 35 of the remote controller 4, and the bath reheating operation is performed according to the operation of the reheating switch 37.

<Bathtub circulation channel switching device>
Next, the bathtub circulation flow path switching device 8 will be described. 39 is a forward flow path connected to the forward pipe 21, 40 is a return flow path connected to the return pipe 22, and 41 is a forward flow path 39 and a return flow path. A bypass flow path that short-circuits 40 and 42 is provided at a branch point between the forward flow path 39 and the bypass flow path 41, closes the bypass flow path 41 side when the temperature of the flowing hot water is high, and the forward flow path 39 is a temperature sensitive switching valve that opens the bypass channel 41 side and closes the bathtub 2 side of the forward flow channel 39 when the temperature of the flowing hot water is low, and 43 is a return flow channel 40. It is a start-up flow path part as a steam-water separation part provided in the middle.

  The temperature-sensitive switching valve 42 includes a temperature-sensitive deformation member 44 that expands and contracts according to the temperature of the flowing hot water, a valve body 45 that is moved by the temperature-sensitive deformation member 44, and the valve body 45 that is connected to the temperature-sensitive deformation member 44. A bias spring 46 urging in the opposite direction is provided in the casing 47, and the casing 47 has an inlet 48 for circulating hot water from the bath water heater 3 side of the forward flow path 39 to the temperature-sensitive deformation member 44 side. The bathtub-side outlet 49 is closed by the valve body 45 when the temperature of the flowing hot water is low, and the bypass-side outlet 50 is closed by the valve body 45 when the temperature of the flowing hot water is high.

  Here, the temperature-sensitive deformation member 44 is formed of a shape memory alloy compression coil spring that expands when the temperature is high and contracts when the temperature is low, and the valve element is formed by the force relationship between the shape memory alloy compression coil spring and the bias spring 46. 45, the bypass side outlet 50 is opened at a position where the valve body 45 is located when the temperature-sensitive deformation member 44 is extended, and the valve body 45 is located when the temperature-sensitive deformation member 44 is contracted. A bathtub-side outlet 49 is opened at the site.

  The shape memory alloy compression coil spring has a low temperature feeling even when it flows into the bathtub 2 and a temperature lower than the bath setting temperature at which the user can arbitrarily set the hot water of the bathtub 2 (for example, 30 ° C.). The above is designed as a shape recovery temperature. Under an atmosphere below the shape recovery temperature, the spring force of the shape memory alloy compression coil spring is weaker than the spring force of the bias spring 46 and is compressed by being pressed by the bias spring 46. In an atmosphere at or above the shape recovery temperature, the spring force of the shape memory alloy compression coil spring is stronger than the spring force of the bias spring 46 and stretches against the bias spring 46. And low temperature in this specification shows temperature below shape recovery temperature, and high temperature shows temperature above shape recovery temperature.

  The rising flow path portion 43 is connected to the upper end of the return flow path 40 on the side of the bath water heater 3 and has a predetermined height lower than the height position where the return flow path 40 of the rise flow path portion 43 is connected. The return channel 40 is connected to the bathtub 2 side of the return channel 40 with a difference, and the bypass channel 41 is connected to the lower end of the rising channel unit 43. The side is at least horizontal, preferably downgraded toward the bathtub 2 as the highest point of the connection point with the rising flow path portion 43.

  The bathtub 2 side of the forward flow path 39 is connected to the discharge port 6 a of the bathtub circulation port 6, and the bathtub 2 side of the return flow path 40 is connected to the suction port 6 b of the bathtub circulation port 6.

<Hot water supply operation>
Next, the operation of this bath hot water supply system will be described from the hot water supply operation.
When the currant 5 is opened and the hot water supply flow counter 17 detects a flow rate higher than a predetermined flow rate and detects hot water supply, the control unit 38 detects the hot water supply temperature sensor 16 so that the temperature detected by the hot water supply temperature sensor 16 is preset by the remote controller 4. When the opening of the hot water supply mixing valve 14 is feedback-controlled so as to match the above, and the currant 5 is closed and the hot water supply flow rate counter 17 detects a flow rate less than the predetermined flow rate, the hot water supply operation is terminated.

<Water filling operation>
The hot water filling operation will be described based on the flowchart of FIG. 2. When the hot water filling switch 35 of the remote controller 4 is turned on while the bathtub 2 is empty (Yes in step S1), the control unit 38 sets the three-way valve for the bath. 27 is switched to the bypass side (step S2), the hot water filling valve 29 is opened to the water side, the hot water filling valve 29 is opened, and when the bath flow counter 30 counts a predetermined amount, the hot water filling valve 29 is closed and the bath circulation pump The water is priming to 23 (step S3), and then the bath circulation pump 23 is started to be driven (step S4).

  At this time, as shown in FIG. 3, when the bath circulation pump 23 is driven, the low-temperature residual water in the forward pipe 21 and the return pipe 22 and the water supplied by the priming operation are switched from the forward pipe 21 to the bathtub circulation flow path. It flows into the forward flow path 39 of the device 8. Since the water flowing into the temperature-sensitive switching valve 42 is low in temperature, the temperature-sensitive deformation member 44 is contracted, the valve body 45 closes the bathtub-side outlet 49, the bypass-side outlet 50 is opened, and the water from the forward flow path 39 is It flows through the bypass channel 41 and flows into the rising channel unit 43. The water that has flowed into the startup channel 43 is discharged from the return channel 40 side of the bathtub 2 into the bathtub 2 through the suction port 6b of the bathtub circulation port 6, and at the same time, the suction port 6b of the bathtub circulation port 6 The air sucked from the air flows backward from the bathtub 2 side of the return flow path 40 and flows into the rising flow path section 43, and to the bath water heater 3 side of the return flow path 40 connected to the upper part of the rising flow path section 43. It is sucked in.

  Here, in the start-up flow channel portion 43, the bath water heater 3 side of the return flow channel 40 is connected to the upper portion with a predetermined height difference, and the bathtub 2 side of the return flow channel 40 is connected to the lower flow channel. The hot water flowing from 41 to the rising flow path portion 43 and the air sucked from the bathtub 2 side of the return flow path 40 are sufficiently separated, and only the air flows to the bath water heater 3 side of the return flow path 40; Become.

  Then, the control unit 38 determines whether or not the flowing water sensor 25 continuously detects the flowing water after starting the bath circulation pump 23 (step S5 in FIG. 2), and at this time, from the return pipe 22 Since the air returns, the flowing water sensor 25 cannot detect flowing water and makes a No determination in step S5 to determine whether the bathtub 2 is empty. The control unit 38 stops driving the bath circulation pump 23 (step S6). ), The hot water filling valve 29 is opened (step S7), and the opening degree of the hot water mixing valve 14 is feedback-controlled so that the temperature detected by the hot water temperature sensor 16 matches the bath set temperature set by the remote controller 4. .

  At this time, the hot water flowing in from the hot water filling pipe 28 flows into the bathtub circulation flow path switching device 8 via the forward pipe 21 and the return pipe 22, and the hot water flowing in from the return flow path 40 passes through the rising flow path section 43. It passes through the bathtub 2 side of the return channel 40 and is filled with water from the suction port 6b of the bathtub circulation port 6 into the bathtub 2, and at the same time, the hot water flowing into the temperature sensitive switching valve 42 from the forward channel 39 is cooled. 4, since the temperature-sensitive switching valve 42 closes the bathtub-side outlet 49 and opens the bypass-side outlet 50, the hot water flowing into the temperature-sensitive switching valve 42 from the forward flow path 39 is It flows out from the bathtub 2 side of the bypass channel 41 and the return channel 40, and flows out into the bathtub 2 from the suction port 6 b of the bathtub circulation port 6.

  Then, when the hot water adjusted to the bath set temperature by the hot water supply mixing valve 14 flows into the bathtub circulation flow path switching device 8 via the forward pipe 21 and the return pipe 22, as shown in FIG. Since the valve 42 is switched to a state in which the bypass side outlet 50 is closed and the bathtub side outlet 49 is opened, the hot water flowing into the temperature sensing switching valve 42 from the forward flow path 39 flows out from the bathtub 2 side of the forward flow path 39. Then, both the hot water fillings can be carried out using both the forward pipe 21 and the return pipe 22 by flowing out from the discharge port 6a of the bathtub circulation port 6 into the bathtub 2.

  When the flow rate accumulated by the bath flow counter 30 after opening the hot water filling valve 29 in step S7 of FIG. 2 reaches the set hot water filling amount (Yes in step S8), the control unit 38 turns the hot water filling valve 29 on. The valve is closed (step S9), and the hot water filling operation is terminated (step S10).

  On the other hand, when the hot water filling switch 35 is turned on in a state where there is more hot water than the amount by which the bathtub circulation port 6 is submerged in the bathtub 2, the return flow path 40 is also submerged as shown in FIG. Therefore, even if the temperature-sensitive switching valve 42 closes the bathtub 2 side of the outgoing flow path 39, the circulation is established, and the controller 38 continues the flowing water for a predetermined time in step S5 of FIG. This is detected, and it is determined that there is remaining hot water in the bathtub 2, the driving of the bath circulation pump 23 is stopped (step S11), and the hot water filling operation is stopped (step S12).

  In this way, when the low-temperature residual water in the bath circulation circuit 7 flows from the forward flow path 39 of the bathtub circulation flow path switching device 8 while the bathtub 2 is empty, the temperature-sensitive switching valve 42 is moved to the bathtub of the forward flow path 39. The two sides are closed and the bypass channel 41 side is communicated, and hot water flows into the rising channel unit 43. Hot water that has flowed into the rising flow path portion 43 is discharged to the bathtub 2 through the return flow path 40, and at the same time, air flows in from the bathtub 2 side of the return flow path 40, and returns through the rising flow path portion 43. Air will flow into the flow path 40 on the side of the bath water heater 3. Therefore, when the bathtub 2 is empty, the circulation is not established only by the residual water in the bath circulation circuit 7, and the bath water heater 3 can reliably recognize that the bathtub 2 is empty. It is possible to prevent the occurrence of defects due to detection.

<Bath chasing operation>
Next, the bath chasing operation will be described with reference to the flowchart of FIG. 7. When the chasing switch 37 is turned on in a state where there is more hot water in the bathtub 2 than the bath circulation port 6 is submerged (step). The control unit 38 switches the bath three-way valve 27 to the bath heat exchanger 20 side (step S22) and starts driving the bath circulation pump 23 (step S23).

  At this time, as shown in FIG. 8, the low-temperature residual water in the forward pipe 21 flows into the forward flow path 39 of the bathtub circulation flow path switching device 8 by driving the bath circulation pump 23. Since the water flowing into the temperature-sensitive switching valve 42 is low in temperature, the temperature-sensitive deformation member 44 is contracted, the valve body 45 closes the bathtub-side outlet 49, the bypass-side outlet 50 is opened, and the water from the forward flow path 39 is It flows through the bypass flow path 41 and flows into the rising flow path section 43, and circulates from the upper part of the rising flow path section 43 through the return flow path 40 to the bath water heater 3 side.

  When hot water heated by the bath heat exchanger 20 circulates and flows into the temperature sensing switching valve 42 of the bathtub circulation channel switching device 8, as shown in FIG. 45 opens the bathtub-side outlet 49 and closes the bypass-side outlet 49, and the hot water from the outgoing flow path 39 is discharged from the bathtub-side outlet 49 through the bathtub 2 side of the outgoing flow path 39. At the same time as it flows into the bathtub 2 from 6a, the bathtub water sucked from the suction port 6b of the bathtub circulation port 6 flows through the return flow path 40 and circulates.

  Simultaneously with or before and after the flow path switching operation of the temperature-sensitive switching valve 42, when the flowing water sensor 25 continues to detect flowing water for a predetermined time or longer (Yes in step S24 in FIG. 7), the bath chase operation is continued. When the bath water temperature detected by the bath temperature sensor 24 reaches a temperature higher than the bath set temperature (here, bath set temperature + 1 ° C) (Yes in step S25), the bath circulation pump 23 is stopped driving (step S25). S26), the bath three-way valve 27 is returned to the bypass side (step S27), and the bath chase operation is ended (step S28).

  Thus, at the beginning of the start of the bath chase operation, the low-temperature residual water remaining in the forward pipe 21 does not flow into the bathtub 2, so that the bath water temperature is not lowered and the bath chase operation is performed. Discomfort can be prevented for bathers expecting to supply hot water.

  On the other hand, when the reheating switch 37 is turned on while the bathtub 2 is empty, the low-temperature residual water in the forward pipe 21 is the temperature-sensitive switching valve of the bathtub circulation flow path switching device 8 at the beginning of the bath reheating operation. 42, the bathtub-side outlet 49 is closed and the bypass-side outlet 50 is opened, but the water that flows into the rising channel section 43 is the bathtub of the return channel 40 as in FIG. At the same time as being discharged into the bathtub 2 through the suction port 6b of the bathtub circulation port 6 from the second side, air sucked from the suction port 6b of the bathtub circulation port 6 flows backward from the bathtub 2 side of the return channel 40. It flows into the rising flow path part 43 and is sucked into the bath water heater 3 side of the return flow path 40 connected to the upper part of the rising flow path part 43.

  And since the bath water heater 3 side of the return flow path 40 is connected to the upper part with a predetermined height difference in the startup flow path part 43 and the bathtub 2 side of the return flow path 40 is connected to the lower part, the bypass flow path 41 The hot water flowing into the start-up flow path portion 43 and the air sucked from the bathtub 2 side of the return flow path 40 are sufficiently separated, and only air flows to the bath water heater 3 side of the return flow path 40. .

  When hot water heated by the bath heat exchanger 20 circulates and flows into the temperature sensing switching valve 42 of the bathtub circulation channel switching device 8, the temperature sensing deformation member 44 extends and the valve body 45 opens the bathtub outlet 49. While being opened, the bypass side outlet 49 is closed, and the hot water from the outgoing flow path 39 flows out from the outlet 6a of the bathtub circulation port 6 into the bathtub 2 through the bathtub 2 side of the outgoing flow path 39 from the bathtub side outlet 49. At the same time, air is sucked from the suction port 6b of the bathtub circulation port 6, and circulation is not established.

  Therefore, the running water sensor 25 cannot continuously detect running water for a predetermined time or more, and No in step S24 in FIG. 7, and the control unit 38 stops driving the bath circulation pump 23 (step S29). The three-way valve 27 is returned to the bypass side (step S30), and the bath chase operation is stopped (step S31).

  In this way, even in the bath chase operation, it can be reliably determined that the bathtub 2 is in an empty state, and the useless operation is not continued, and the occurrence of problems due to erroneous detection is prevented. be able to.

<Anti-freezing operation>
Next, in winter and the like, freezing of the forward pipe 21 and the return pipe 22 in the bath water heater 3 and the forward pipe 21 and the return pipe 22 that connect the bath water heater 3 and the bathtub circulation channel switching device 8 is prevented. The freeze prevention operation for this will be described based on the flowchart of FIG.

  First, when the bath temperature sensor 24 or the water supply temperature sensor 18 detects a predetermined freezing prevention start temperature or lower (Yes in step S41), the control unit 38 switches the bath three-way valve 27 to the bypass side (step S42), Driving of the circulation pump 23 is started (step S43).

  At this time, in a situation where there is hot water in the bathtub 2, low temperature residual water in the forward pipe 21 is driven to the forward flow path 39 of the bathtub circulation flow path switching device 8 by driving the bath circulation pump 23, as shown in FIG. 6. Inflow. Since the water flowing into the temperature-sensitive switching valve 42 is low in temperature, the temperature-sensitive deformation member 44 is contracted, the valve body 45 closes the bathtub-side outlet 49, opens the bypass-side outlet 50, and the water from the forward flow path 39 It flows through the bypass flow path 41 and flows into the rising flow path section 43, and circulates from the upper part of the rising flow path section 43 through the return flow path 40 to the bath water heater 3 side.

  When the flowing water sensor 25 continues to detect flowing water for a predetermined time or longer (Yes in step S44 in FIG. 7), the control unit 38 continues to drive the bath circulation pump 23 and freezes hot water in the piping by circulating hot water. When the time since the start of the operation and the start of the bath circulation pump 23 is equal to or longer than a predetermined pump-on time (here, 10 minutes) (Yes in step S45), the operation of the bath circulation pump 23 is temporarily stopped ( Step S46).

  When the time after the bath circulation pump 23 is stopped is equal to or longer than a predetermined pump-off time (20 minutes in this case) (Yes in step S47), the bath temperature sensor 24 or the feed water temperature sensor 18 is more than the anti-freezing start temperature. It is determined whether or not a temperature equal to or higher than a predetermined predetermined freeze prevention end temperature is detected (step S48). If the temperature is equal to or lower than the freeze prevention end temperature, the process returns to step S43, and the bath circulation pump 23 is driven again to prevent the freeze operation. On the other hand, when the freeze prevention end temperature or higher is detected (Yes in step S48), the freeze prevention operation is temporarily interrupted and the process returns to step S41 to wait for the start of the freeze prevention operation. .

  On the other hand, in the situation where the bathtub water is drained and there is no hot water in the bathtub 2 or the bathtub water is drained and no hot water is left in the bathtub 2 after the freeze prevention operation is started, the low temperature residual in the forward pipe 21 remains. Water flows into the temperature-sensitive switching valve 42 of the bathtub circulation channel switching device 8, closes the bathtub-side outlet 49, and opens the bypass-side outlet 50. As in FIG. The water that flowed into the portion 43 was discharged into the bathtub 2 from the return channel 40 side of the bathtub 2 through the suction port 6 b of the bathtub circulation port 6 and simultaneously sucked from the suction port 6 b of the bathtub circulation port 6. The air flows backward from the bathtub 2 side of the return flow path 40 and flows into the rising flow path section 43, and is sucked and circulated to the bath water heater 3 side of the return flow path 40 connected to the upper part of the rising flow path section 43. Does not hold.

  Therefore, in step S44 of FIG. 10, the flowing water sensor 25 does not remain on for a predetermined time, so that the answer is No in step S44, and the control unit 38 stops driving the bath circulation pump 23 (step S49). The useless operation of the bath circulation pump 23 is stopped, and after the pump-off time has elapsed, the process proceeds to step S47, and the process proceeds again from step S48 to step S41 or step S43 to prevent freezing of hot water remaining in the bath circulation pump 23. I have to.

  Thus, it is possible to reliably determine that the bathtub 2 is in an empty state even in the anti-freezing operation, and the useless operation is not continued, thereby preventing the occurrence of problems due to erroneous detection. Can do.

  As described above, the bathtub circulation channel switching device 8 according to the present invention can prevent the low-temperature hot water from being discharged into the bathtub 2 during circulation when the hot water is in the bathtub 2 and the inside of the bathtub 2. Since the hot water flowing in from the forward flow path 39 can be discharged into the bathtub 2 in an empty state, hot water circulates between the bath water heater 3 and the bathtub 2 while the bathtub 2 is empty. It is something that never ends.

  Further, in such a bathtub circulation flow path switching device 8, after the bath circulation pump 23 is driven, the flowing water sensor 25 determines whether or not hot water is in the bathtub 2 by determining circulation of hot water. By using it together with the bath water heater 3, it becomes possible to accurately determine the presence or absence of remaining hot water in the bathtub 2 in the bath water heater 3, and the bath when misidentifying that there is hot water even though the bathtub 2 is empty The malfunction of the water heater 3 can be prevented.

  In addition, this invention is not limited to said one Embodiment, For example, as temperature sensing deformation member 44 of temperature sensing switching valve 42 built in bathtub circulation channel switching device 8, temperature is higher than shape recovery temperature. When the temperature is higher than the temperature corresponding to the shape recovery temperature, the shape memory alloy tension coil spring that expands when the temperature is lower than the shape recovery temperature or expands when the temperature is higher than the temperature corresponding to the shape recovery temperature. For example, a wax thermoelement that shrinks to a high temperature may be used.

  Moreover, the bathtub circulation flow path switching device 8 should just be the structure which provided the starting flow path part 43 which acts as a steam-water separation part in the middle of the return flow path 40, and as shown in FIG. The bypass channel 41 may be connected to the bathtub 2 side with respect to the rising channel portion 43 of the return channel 40. Here, the bypass channel 41 is connected to the bathtub 2 side from at least the upper end of the rising channel unit 43 so that the flow to the bath water heater 3 side can be separated into air and water.

  Moreover, although the heater 10 was provided in the hot water storage tank 9 as the bath hot water supply device 3 as a heat source device, it is not limited to this, and a heat pump type heating device is provided outside the hot water storage tank 9, A configuration in which hot water is circulated and heated, a bath heat exchanger 20 is arranged outside the hot water storage tank 9, and the hot water in the hot water storage tank 9 is circulated to the primary side of the bath heat exchanger, or water and bath water are supplied A configuration having an instantaneous heat exchanger (bath heat exchanger) for heating with a gas burner or an oil burner may be used.

  The running water sensor 25 only needs to be able to determine whether hot water is circulating in the bath circulation circuit 7, and detects a running water switch that turns on when there is a flow of a predetermined amount or more, or the flow amount itself. Various known devices such as a flow rate counter can be used.

  In this embodiment, the freeze prevention start temperature and the freeze prevention end temperature are detected by the water supply temperature sensor 18 or the bath temperature sensor 24. However, the present invention is not limited to this, and an outside air temperature sensor that detects the outside air temperature, In addition, an in-machine temperature sensor that detects the ambient temperature in the bath water heater 3 may be provided to detect the anti-freezing start temperature and the anti-freezing end temperature.

2 Bath 3 Bath Hot Water Heater 6 Bath Circulation Port 6a Discharge Port 6b Suction Port 7 Bath Circulation Circuit 8 Bath Circulation Channel Switching Device 20 Bath Heat Exchanger 21 Outward Pipe 22 Return Pipe 23 Bath Circulation Pump 25 Flow Water Sensor 26 Bath Bypass Pipe 39 Outward flow path 40 Return flow path 41 Bypass flow path 42 Temperature-sensitive switching valve 43 Start-up flow path section (air / water separation section)
44 Temperature-sensitive deformation member 45 Valve body 46 Bias spring

Claims (5)

  A forward flow path from the heat source machine for heating the bathtub water to the bathtub, a return flow path from the bathtub to the heat source machine, a bypass flow path for short-circuiting the forward flow path and the return flow path, and flowing hot water When the temperature is high, the bypass flow path side is closed to connect the heat source machine side of the forward flow path and the bathtub side, and when the temperature of the flowing hot water is low, the bathtub side of the forward flow path is blocked. In the one provided with a temperature-sensitive switching valve that communicates with the bypass flow path side and the heat source machine side of the forward flow path, an air-water separator is provided in the middle of the return flow path, and the heat source machine side of the return flow path is It is connected to the upper part of the steam / water separation part, and the bathtub side of the return flow path is connected to the lower part having a predetermined height difference from the connection height of the return flow path on the heat source unit side of the return flow path. The bathtub circulation channel switching device.   The bathtub circulation channel switching according to claim 1, wherein an end of the bypass channel on the return channel side is connected to the bathtub side with respect to the steam / water separation unit or the steam / water separation unit of the return channel. apparatus.   The temperature-sensitive switching valve includes a temperature-sensitive deformation member that expands and contracts in accordance with the temperature of the flowing hot water, a valve body that is moved by the temperature-sensitive deformation member, and the valve body in a direction opposite to the temperature-sensitive deformation member. The bathtub circulation channel switching device according to claim 1, further comprising a bias spring for biasing.   The bathtub circulation channel switching device has a discharge port for discharging into the bathtub and a suction port for sucking in the water in the bathtub, and is installed between the bathtub circulation port and the heat source unit attached to the bathtub wall surface and in the vicinity of the bathtub circulation port. The bathtub circulation channel switching device according to claim 1, wherein the bathtub circulation channel switching device is provided.   As the heat source machine, a bath heat exchanger that heats bathtub water, a bath circulation circuit that connects the bathtub and the bath heat exchanger so that the bath water can circulate, and a bath circulation provided in the middle of the bath circulation circuit A pump and a running water sensor that detects whether hot water is circulating in the bath circulation circuit, and after the bath circulation pump is driven, the running water sensor determines circulation of hot water in the bathtub. The bath circulation flow path switching device according to claim 4 is used between a bath circulation port and the bath water heater and in the vicinity of the bath circulation port, using a bath water heater configured to determine whether there is hot water or not. A bath hot water system characterized by being provided.

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