JP6672834B2 - Water level detector - Google Patents

Description

  The present invention relates to a water level detection device, and more particularly to a water level detection device capable of detecting a water level of water stored in a bathtub while being attached to the bathtub.

  Conventionally, some commercial bath apparatuses use a system configuration for automatically maintaining a water level in a bathtub. In such a system configuration, a water level detection device is used to detect the level of the hot water supplied to the bathtub. For example, when the water level in the bathtub is lower than the reference water level according to a signal from the water level detection device, hot water supply to the bathtub is controlled.

  Some of the above water level detection devices are directly attached to a bathtub. For example, Japanese Unexamined Patent Application Publication No. 2005-206682 (Patent Document 1) and Japanese Patent No. 2926762 (Patent Document 2) use a pressure sensor attached to a wall surface of a bathtub and detecting a water level by the pressure of hot water in the bathtub. A water level detection device is described.

  In the water level detection devices described in Patent Documents 1 and 2, as a pressure sensor, the pressure of hot and cold water stored in a bathtub is received by a diaphragm, and a detection signal corresponding to the pressure is output from a piezoelectric conversion element formed in the diaphragm. The structure which makes it do is adopted. Such a pressure sensor generally uses the atmospheric pressure as a reference pressure by opening one side of a diaphragm to the atmosphere.

JP 2015-206682 A Japanese Patent No. 2926762

  In a commercial bath device, the water level detection device is attached to the bathtub at the site where the bathtub is located. For this reason, the watertightness of the water level detection device may not be ensured depending on the arrangement and shape of the bathtub. In a commercial bath device, bathtub water may leak into a gap between the water level detection device and the bathtub, or bathtub water may seep into mortar outside the bathtub. Therefore, when the bathtub water contacts the pressure sensor of the water level detection device in a state where the water level of the water level detection device is not ensured, the water level detection device may break down.

  On the other hand, if the water level detection device is closed to ensure watertightness of the water level detection device, one side of the diaphragm of the pressure sensor cannot be opened to the atmosphere, so the reference pressure of the pressure sensor deviates from the atmospheric pressure. There is a possibility that it will end This may make it impossible to accurately detect the water level in the bathtub.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a water level detection device for detecting a water level of water stored in a bath tub with high accuracy and suppressing a failure due to contact with bath tub water. Is to provide a configuration.

  According to one aspect of the present invention, the water level detection device is capable of detecting the level of water stored in the bathtub while being installed on the side wall of the bathtub. The water level detection device includes a housing member having an internal space separated from the bathtub, a pressure sensor housed in the internal space of the housing member, capable of detecting the water pressure of the bathtub, and a signal line electrically connected to the pressure sensor. And The housing member has a through hole for drawing out the signal line from the internal space to the outside of the housing member, and the through hole is sealed watertight. The housing member further has an air introduction hole configured to hermetically seal the internal space and to introduce air into the internal space.

  According to the above water level detection device, since the atmosphere can be introduced into the internal space of the housing member that houses the pressure sensor through the air introduction hole, the air pressure in the internal space can be maintained at the atmospheric pressure. Accordingly, the pressure sensor can accurately detect the water pressure in the bathtub using the atmospheric pressure as the reference pressure, and as a result, can accurately detect the level of the hot water stored in the bathtub.

  According to the water level detection device, the housing member is further sealed in a watertight manner in the through hole through which the signal line is inserted, and the internal space is sealed in the air introduction hole in a watertight manner. Even if bathtub water flows into the outside, watertightness of the internal space can be ensured. For this reason, it can suppress that a water level detection apparatus breaks down when a pressure sensor contacts bathtub water.

  Preferably, a pipe for drawing out the signal line to the outside of the side wall is buried inside the side wall. The housing member is configured to be installable on the side wall by connecting the signal line to the pipe while being inserted through the pipe. The air introduction hole is formed so as to communicate the internal space of the housing member with the inside of the pipe.

  With this configuration, in a state where the housing member is attached to the bathtub, the atmosphere can be introduced into the internal space of the housing member from the inside of the pipe through the air introduction hole. Further, even if bathtub water flows into the pipe from the connection between the housing member and the pipe, watertightness of the internal space of the housing member can be ensured.

Preferably, the air introduction hole is formed at a height position higher than the through hole.
With this configuration, it is possible to make it difficult for the bathtub water flowing into the outside of the housing member to come into contact with the air introduction hole in a state where the housing member is attached to the side wall of the bathtub. Therefore, even if bathtub water flows in, the atmosphere can be introduced into the internal space of the housing member, so that the level of the hot water stored in the bathtub can be accurately detected.

Preferably, the air introduction hole is formed at a height above the pipe.
By doing so, even if bathtub water flows into the piping, it is possible to make it difficult for the bathtub water to come into contact with the air introduction hole, so that the atmosphere can be inserted into the internal space of the housing member.

  Preferably, the housing member includes an inner case that houses the pressure sensor, and an outer case that houses the inner case. The through hole and the air introduction hole are formed in the inner case. A gap is formed between the outer peripheral surface of the inner case and the inner peripheral surface of the outer case, which communicates the inside of the inner case with the outside of the outer case through an air introduction hole and contains air.

  With this configuration, air can be kept in the gap between the inner case and the outer case, so that air is interposed between the bathtub water and the air introduction hole. Thereby, since bathtub water can be prevented from contacting the air introduction hole, the effect of ensuring watertightness of the internal space of the housing member can be enhanced.

  Preferably, the water level detection device further includes a sealing member attached between the outer peripheral surface of the signal line and the through hole. With this configuration, it is possible to prevent bathtub water from flowing into the internal space of the housing member from the gap between the outer peripheral surface of the signal line and the through hole.

  ADVANTAGE OF THE INVENTION According to this invention, the water level detection apparatus which can detect the water level of the water stored in the bathtub with high precision can be provided.

It is sectional drawing which shows the state which attached the water level detection apparatus according to this Embodiment to a bathtub. 1 is a perspective view schematically showing an appearance of a water level detecting device according to the present embodiment. FIG. 3 is a cross-sectional perspective view schematically showing a configuration of a water level detecting device according to the present embodiment along line III-III in FIG. 2. It is sectional drawing which shows the structure of a water level sensor unit schematically. It is sectional drawing which shows the structure of a pressure sensor schematically. It is sectional drawing which shows the state which attached the water level detection apparatus according to this Embodiment to a bathtub. It is sectional drawing which shows the state which attached the water level detection apparatus according to this Embodiment to a bathtub. It is sectional drawing which shows the state in which the water level detection apparatus according to the modification of this Embodiment was attached to the bathtub.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following, the same or corresponding parts in the drawings are denoted by the same reference characters, and description thereof will not be repeated in principle.

  First, a state in which water level detecting device 100 according to one embodiment of the present invention is attached to a bathtub will be described with reference to FIG. Water level detecting apparatus 100 according to the present embodiment is capable of detecting the level of water stored in a bathtub while being attached to the bathtub, and is suitably used for a commercial bath apparatus. In addition, in FIG. 1, the side surface of the water level detection device 100 is shown for easy viewing.

  Referring to FIG. 1, bathtub 200 has an inner area surrounded by an inner wall of bathtub 200. Bathtub 200 is configured to be able to store hot water in the inner area. Further, a waterproof layer 201 is formed inside the bathtub 200. The waterproof layer 201 is formed along the inner wall of the bathtub 200. That is, the waterproof layer 201 is formed from the bottom to the side wall of the bathtub 200. FIG. 1 shows a state in which hot water 300 is stored in an inner region of bathtub 200.

  The water level detecting device 100 is attached to a side wall of the bathtub 200. The water level detecting device 100 includes an outer case 10, a pipe 40, a water cutter 42, and an output signal line 70. The distal end of the second cylindrical member 12 of the outer case 10 is arranged on the inner wall side of the bathtub 200, that is, on the inner region of the bathtub 200. A pipe 40 is arranged on the outer wall side of the bathtub 200.

  The water cutter 42 is attached to the waterproof layer 201. The water cutter 42 is for retaining bathtub water flowing from the outer case 10 side. The water cutter 42 has a disk portion. The disk portion protrudes from the outer peripheral surface of the pipe 40 in the radial direction of the pipe 40. The disk portion is provided over the entire circumference of the pipe 40.

  The pipe 40 is drawn out of the bathtub 200, and the output signal line 70 inserted through the pipe 40 is electrically connected to the control unit 400. The control unit 400 is also electrically connected to a hot water supply unit (not shown). The control unit 400 is configured to be able to control the water level detection device 100 and the supply unit.

  The control unit 400 compares the height between the water level detected by the water level detection device 100 and a predetermined reference water level. When the detected water level is lower than the reference water level, the supply unit is controlled based on the output signal of the water level detection device 100 to supply hot water 300 from the supply unit (not shown) to the bathtub 200. Thereby, hot water 300 is supplied to bathtub 200. Hot water 300 is supplied to bath tub 200 until water level detecting device 100 detects that the water level in bath tub 200 has reached the reference water level.

  Next, a configuration of water level detecting apparatus 100 according to the present embodiment will be described with reference to FIGS. FIG. 2 is a perspective view schematically showing an appearance of water level detecting device 100 according to the present embodiment. FIG. 3 is a cross-sectional perspective view schematically showing a configuration of water level detecting device 100 according to the present embodiment along line III-III in FIG.

  Water level detection device 100 according to the present embodiment includes outer case 10, inner case 20, water level sensor unit 30, relay board 35, pipe 40, water cutter 42, output signal line 70, sealing member 50 mainly.

  The inner case 20 is housed in the outer case 10. The water level sensor unit 30 is housed inside the inner case 20. A pipe 40 is connected to the outer case 10. A water cutter 42 is connected to the outer peripheral surface of the pipe 40. An output signal line 70 is electrically connected to the water level sensor unit 30 via a relay board 35. The relay board 35 relays between the output terminal 30f of the water level sensor unit 30 and the output signal line 70.

  In the present embodiment, outer case 10 and inner case 20 constitute a “storage member” that houses water level sensor unit 30. A concave portion for fitting the housing member is formed on the side wall of the bathtub 200. The water level sensor unit 30 is attached to the side wall of the bathtub 200 by fitting the housing member into the concave portion of the side wall.

  The outer case 10 includes a first tubular member 11, a second tubular member 12, a perforated plate 13, a support member 14, and a communication member 15. The first tubular member 11, the second tubular member 12, and the perforated plate 13 are each formed of, for example, stainless steel. The support member 14 and the communication member 15 are formed of, for example, resin.

  The first tubular member 11 has a tubular shape having openings on the second tubular member 12 side and the pipe 40 side, respectively. The first cylindrical member 11 includes a large-diameter portion 11a, a medium-diameter portion 11b, a small-diameter portion 11c, a wall portion 11d connecting the large-diameter portion 11a and the medium-diameter portion 11b, and a medium-diameter portion 11b and a small-diameter portion 11c. And a wall 11e connecting the two.

  The second tubular member 12 is attached to the large diameter portion 11a of the first tubular member 11. The second tubular member 12 is fixed to the large-diameter portion 11a of the first tubular member 11 with a plurality of screws 140.

  The second tubular member 12 has a flange portion 12b for attaching to the side wall of the bathtub 200 (FIG. 1). The flange portion 12b extends outward from the second tubular member 12 in the radial direction of the second tubular member 12. The surface of the flange portion 12b on the first tubular member 11 side is attached to the side wall of the bathtub 200.

  The second cylindrical member 12 has a concave portion 12c on the end surface opposite to the first cylindrical member 11. A perforated plate 13 is fitted into the recess 12c. The perforated plate 13 has a plurality of through holes 13a. The perforated plate 13 is fixed to the second tubular member 12 with a plurality of screws 110.

  The support member 14 is disposed inside the second tubular member 12. The support member 14 supports the water level sensor unit 30. The support member 14 has a disk shape. The outer periphery of the support member 14 is arranged along the inner periphery of the first tubular member 11.

  The outer case 10 has a water receiving chamber 10a that can receive hot and cold water stored in the bathtub 200. The space surrounded by the second tubular member 12, the perforated plate 13, and the support member 14 constitutes the water receiving chamber 10a. The water receiving chamber 10a is configured to receive bathtub water from the plurality of through holes 13a of the perforated plate 13.

  The inner case 20 is disposed inside the first tubular member 11. The inner case 20 is arranged on the opposite side of the support member 14 from the water receiving chamber 10a. The inner case 20 has a first internal space IS1 separated from the water receiving chamber 10a.

  The inner case 20 has a side surface portion 20a, a bottom surface portion 20b, and a flange portion 20c extending outward from the side surface portion 20a in the radial direction of the side surface portion 20a. The side surface portion 20a has, for example, a cylindrical shape. The bottom surface portion 20b has, for example, a disk shape. The bottom surface portion 20b is disposed so as to cover the opening of the side surface portion 20a on the side opposite to the water receiving chamber 10a.

  The support member 14 is attached to the inner case 20 so as to cover the opening of the side surface portion 20a. The support member 14 is fixed to the inner case 20 by a plurality of screws 150. An inner sealing member (not shown) is arranged between the support member 14 and the inner case 20. The inner sealing member is mounted between the outer case 10 and the inner case 20 in order to house the inner case 20 in the outer case 10 in a watertight manner. The inner sealing member is configured to seal a gap between the support member 14 and the inner case 20. The inner sealing member is arranged in a recess provided on the outer wall of the inner case 20. The recess is provided so as to face the surface of the support member 14 on the inner case 20 side. The inner sealing member is, for example, an O-ring made of rubber.

  The inner case 20 is fixed to the outer case 10 by screws 150 inserted into through holes provided in the flange portion 20c of the inner case 20. Inner case 20 is formed of, for example, resin.

  The water level sensor unit 30 is housed in the first internal space IS1 of the inner case 20. The water level sensor unit 30 is configured to be able to detect the water pressure of the water receiving chamber 10a. The water level sensor unit 30 is fixed to the support member 14 by screws (not shown). The tip of the water level sensor unit 30 is inserted into a through hole 14a formed in the center of the support member 14.

  A communication member 15 is disposed on a main surface of the support member 14 on the water receiving chamber 10a side. The communication member 15 is attached to the support member 14 so as to cover the through hole 14a of the support member 14. The communication member 15 is configured to allow communication between the water receiving chamber 10a and the distal end of the water level sensor unit 30. The communication member 15 is made of, for example, resin, and can be formed integrally with the support member 14. Alternatively, the communication member 15 may be detachably connected to the support member 14 separately from the support member 14.

  The relay board 35 is housed in the first internal space IS1. The relay board 35 is fixed to the support member 14 by screws 160. The output terminal 30f of the water level sensor unit 30 and the output signal line 70 are electrically connected via a connector provided on the relay board 35.

  The output signal line 70 has a wiring member 72 for transmitting an electric signal output from the output terminal 30f of the water level sensor unit 30, and a coating tube 71 as a coating covering the wiring member 72. As the wiring member 72, for example, a three-core signal line can be used. The coating tube 71 is a protective coating for protecting the core, and is formed of, for example, resin.

  One end of the pipe 40 is connected to the small diameter portion 11c of the outer case 10. The small diameter portion 11c of the outer case 10 and one end of the pipe 40 are screwed. Specifically, a male screw portion formed on the outer circumferential surface of the small diameter portion 11c and a female screw portion formed on the inner circumferential surface at one end of the pipe 40 are screwed. The pipe 40 is formed of, for example, a resin. The pipe 40 has a second internal space IS2. The second internal space IS2 communicates with the outside of the bathtub 200 at the other end of the pipe 40. The output signal line 70 is inserted through the pipe 40.

  A through hole 20 d for drawing out the output signal line 70 to the outside of the inner case 20 is formed in the bottom surface portion 20 b of the inner case 20. The output signal line 70 extends from the first internal space IS1 to the second internal space IS2 through the through hole 20d. The sealing member 50 is disposed between the outer peripheral surface of the output signal line 70 and the through hole 20d.

  The sealing member 50 is configured to seal a gap between the outer peripheral surface of the output signal line 70 and the through hole 20d in a watertight manner. The sealing member 50 is, for example, a cylindrical rubber bush fitted on the outer peripheral surface of the cladding tube 71. In this case, the gap between the outer peripheral surface of the cladding tube 71 and the through hole 20d may be sealed with the rubber bush as described above, and the rubber bush may be potted with resin or the like.

  An air introduction hole 20e for introducing air into the first internal space IS1 is further formed in the bottom surface portion 20b of the inner case 20. The air introduction hole 20e communicates the first internal space IS1 with the second internal space IS2. The function of the air introduction hole 20e will be described later in detail.

  Next, a configuration of water level sensor unit 30 of water level detecting apparatus 100 according to the present embodiment will be described with reference to FIGS.

  The water level sensor unit 30 mainly has a pressure sensor 30a, a housing 30b, a protection member 30e, and an output terminal 30f. The pressure sensor 30a has a detection surface S for detecting pressure.

  The surface opposite to the detection surface S of the pressure sensor 30a is covered with a protective member 30e. The protection member 30e is formed of an insulating resin or the like, and protects the pressure sensor 30a from moisture and the like.

  The output terminal 30f has conductivity, and one end thereof is electrically connected to the pressure sensor 30a through the protection member 30e. The other end of the output terminal 30f is electrically connected to the wiring member 72 (FIG. 3) of the output signal line 70. As the output terminal 30f, for example, a lead wire can be used.

  The pressure sensor 30a is housed in the housing 30b. Housing 30b is formed of, for example, resin. The housing 30b has a pressure introducing hole 30c and an oil passage 30d.

  One end of the oil passage 30d is connected to the detection surface S of the pressure sensor 30a. The oil passage 30d is filled with a non-corrosive fluid. The non-corrosive fluid is, for example, a fluorine-based oil. The pressure introducing hole 30c is provided so as to expose the other end of the oil passage 30d to the outside of the housing 30b.

  The pressure introducing hole 30c introduces the pressure of the hot and cold water in the bathtub into the oil passage 30d from the direction of the arrow in the figure. The pressure introduced from the pressure introduction hole 30c is transmitted to the detection surface S of the pressure sensor 30a by the oil passage 30d. The pressure sensor 30a is configured to be able to detect the pressure of hot and cold water in the bathtub using the air pressure (atmospheric pressure) in the bathtub as a reference pressure.

FIG. 5 is a sectional view schematically showing the configuration of the pressure sensor 30a in FIG.
Referring to FIG. 5, pressure sensor 30 a of the present embodiment mainly includes a thin diaphragm 31 in which the back surface of the semiconductor substrate is depressed by etching, a base 32 on which diaphragm 31 is mounted, and a sealing member 33. Have. The surface of the diaphragm 31 forms a detection surface S of the pressure sensor 30a. The base 32 is provided with an atmosphere opening hole 32a for opening the back surface of the diaphragm 31 to the atmosphere. The seal member 33 is disposed so as to close the space on the back surface side of the diaphragm 31.

  The pressure sensor 30a has a first chamber S1 partitioned by a diaphragm 31 and a base 32, and a second chamber S2. The diaphragm 31 is configured to be deformable in a convex shape toward the second chamber S2 by a pressure difference between the pressure P1 of the first chamber S1 and the pressure P2 of the second chamber S2. The pressure P1 of the first chamber S1 becomes the pressure of the hot and cold water in the bathtub transmitted through the oil passage 30d. The pressure P2 of the second chamber S2 becomes the atmospheric pressure in the first internal space IS1 of the inner case 20. The air pressure in the first internal space IS1 is the air pressure (atmospheric pressure) of the bathtub.

  The pressure sensor 30a is configured to be able to detect a differential pressure between the atmospheric pressure (atmospheric pressure) in the first internal space IS1 and the pressure of hot and cold water in the bathtub. A gauge (not shown) is formed on the diaphragm 31 by, for example, impurity diffusion into a semiconductor substrate. Four gauges may be formed at positions rotated by 90 ° from the center of the diaphragm 31 in plan view. These four gauges are connected to form a Wheatstone bridge circuit. When a voltage is applied to the Wheatstone bridge circuit, the resistance of the four gauges fluctuates due to deformation of the diaphragm 31, so that the voltage value fluctuates. Therefore, the pressure sensor 30a can detect the pressure based on the fluctuation of the voltage value according to the deformation of the diaphragm 31.

  Subsequently, the configuration of the housing member of the water level sensor unit 30 shown in FIG. 4 will be described in detail with reference to FIG.

  FIG. 6 schematically shows a state where outer case 10 is attached to the wall surface of bathtub 200 with water level sensor unit 30 housed in inner case 20.

  The water level sensor unit 30 is attached to the support member 14 by inserting the tip of the water level sensor unit 30 into the through hole of the support member 14. When the water level sensor unit 30 is attached to the support member 14, the pressure introduction hole 30c (see FIG. 4) of the water level sensor unit 30 opens to the water receiving chamber 10a. Thus, the other end of the oil passage 30d is exposed toward the water receiving chamber 10a through the pressure introducing hole 30c.

  The communication member 15 is connected to the main surface of the support member 14 on the water receiving chamber 10a side. The communication member 15 is formed of, for example, a tubular member. One end of the tubular member is connected to the support member 14 so as to communicate with the pressure introducing hole 30c, and the other end is open to the water receiving chamber 10a. The communication member 15 is formed with an internal space 15a communicating with the pressure introducing hole 30c and the water receiving chamber 10a. The internal space 15a contains air. The communication member 15 has, for example, a hanging portion extending from the pressure introducing hole 30 c side to the bottom side of the bathtub 200 along the main surface of the support member 14.

  FIG. 6 shows a state in which hot and cold water 300 is stored in an inner region of bathtub 200. In this state, hot and cold water 300 enters the inside of the water receiving chamber 10a through the plurality of through holes 13a of the perforated plate 13 (see FIGS. 2 and 3). On the other hand, the internal space 15a of the communication member 15 is filled with air. Therefore, the air pressure of the internal space 15a is equal to the air pressure (atmospheric pressure) of the bathtub 200.

  When the supply of hot water to bathtub 200 is started, the water level in bathtub 200 gradually rises. When the water level of the bathtub 200 exceeds the height of the open end of the communication member 15, the pressure of the hot water in the bathtub 200 is applied to the air in the internal space 15 a of the communication member 15. Here, the pressure of the hot water in the bathtub 200 is a sum of the water pressure of the hot water in the bathtub 200 and the air pressure of the bathtub 200. Since the air pressure in the internal space 15a of the communication member 15 is equal to the air pressure in the bathtub 200, the water pressure of the hot water in the bathtub 200 is substantially added to the air in the internal space 15a.

  The pressure applied to the air in the internal space 15a of the communication member 15 is introduced into the pressure introduction hole 30c of the water level sensor unit 30, and is applied to the end of the oil passage 30d (see FIG. 4). That is, the air pressure corresponding to the water pressure of the hot water in the bathtub 200 is transmitted through the internal space 15a and the pressure introducing hole 30c, and is applied to the end of the oil passage 30d. The oil passage 30d further transmits this pressure to the detection surface S (diaphragm 31) of the pressure sensor 30a. Thereby, the pressure sensor 30a can detect the pressure of the hot and cold water in the bathtub 200.

  In the present embodiment, when the water level detection device 100 is attached to the wall surface of the bathtub 200, the water pressure detected by the pressure sensor 30a when the water level of the bathtub 200 is the reference water level, and the water pressure detected by the pressure sensor 30a. By converting the pressure difference from the water pressure into a water level change amount from the reference water level, the water level of the hot water 300 stored in the bathtub 200 can be detected.

Hereinafter, the operation and effect of the water level detection device 100 of the present embodiment will be described.
In water level detection device 100 according to the present embodiment, through hole 20 d is sealed by sealing member 50 in the bottom surface portion 20 b of inner case 20 in a watertight manner. Therefore, even if bathtub water flows into the pipe 40, the watertightness of the first internal space IS1 of the inner case 20 can be ensured. Thereby, it is possible to suppress the water level detection device 100 from being broken due to the contact of the bathtub water with the water level sensor unit 30 housed in the first internal space IS1 of the inner case 20.

  Specifically, a concave portion for fitting the first tubular member 11 of the outer case 10 is provided on a side wall of the bathtub 200. Further, a pipe 40 is buried inside the side wall so as to communicate with the concave portion. By fitting the first tubular member 11 into this concave portion and connecting the small diameter portion 11c of the first tubular member 11 and one end of the pipe 40, the water level detecting device 100 is attached to the side wall of the bathtub 200. Can be attached.

  When the water level detection device 100 is attached to the side wall of the bathtub 200, bathtub water may flow into a gap between the outer peripheral surface of the first tubular member 11 of the outer case 10 and the side wall of the bathtub 200. When the bathtub water flows into the gap, as shown by an arrow in FIG. 6, the bathtub enters the inside of the pipe 40 through a connection portion between the small-diameter portion 11 c of the first tubular member 11 and one end of the pipe 40. Water may enter. As a result, the second internal space IS2 of the pipe 40 may be in a state where bathtub water is accumulated.

  Even in such a state, since the watertightness of the first internal space IS1 of the inner case 20 is ensured by the sealing member 50, bathtub water is prevented from flowing into the first internal space IS1 of the inner case 20. can do.

  On the other hand, as described above, the pressure sensor 30a in the water level sensor unit 30 is configured to detect the pressure of hot or cold water in the bathtub 200 based on the air pressure (atmospheric pressure) of the bathtub 200. Therefore, in the present embodiment, the pressure of the first internal space IS1 corresponding to the pressure P2 of the second chamber S2 of the pressure sensor 30a (see FIG. 5) needs to be maintained at the air pressure (atmospheric pressure) of the bathtub 200. There is.

  However, if the inner case 20 is closed in order to secure the watertightness of the first inner space IS1 of the inner case 20, a deviation occurs between the air pressure of the first inner space IS1 and the air pressure of the bathtub 200. In some cases, the reference pressure in the pressure sensor 30a cannot be maintained at the atmospheric pressure. As a result, it is difficult to accurately detect the pressure of the hot and cold water in the bathtub 200 with the pressure sensor 30a, and the detection accuracy of the water level in the bathtub 200 may be reduced.

  Therefore, in the present embodiment, a through-hole 20 e is formed in the inner case 20 to communicate the first internal space IS <b> 1 with the second internal space IS <b> 2 of the pipe 40. This through hole 20e can be an air introduction hole for introducing air into the first internal space IS1. Thereby, the air pressure of the first internal space IS1 can be maintained at the air pressure of the bathtub 200.

  Here, the opening diameter of the air introduction hole 20e is large enough to prevent bathtub water from entering the first internal space IS1 so as not to impair the watertightness of the first internal space IS1. I have. For example, the opening diameter of the air introduction hole 20e can be about 1 to 2 mm.

  When the opening diameter of the atmosphere introduction hole 20e is increased, the atmosphere can be easily introduced into the first internal space IS1 of the inner case 20. On the other hand, when bathtub water flows into the pipe 40, A phenomenon in which the bath water accumulated in the second internal space IS2 of the pipe 40 is replaced with the air in the first internal space IS1 is likely to occur. The opening diameter of the air introduction hole 20e is set to a size that can prevent such replacement of bathtub water with air.

  With this configuration, if the air introduction hole 20e is not in contact with the bathtub water, the first internal space IS1 of the inner case 20 is opened to the atmosphere through the air introduction hole 20e. The water level of the hot water stored in 200 can be accurately detected.

  When bath water accumulates inside the pipe 40 and the air introduction hole 20e comes into contact with the bath water, the first internal space IS1 cannot be opened to the atmosphere, but the first internal space IS1 cannot be opened to the atmosphere. By preventing the bath water from flowing into the space IS1, the watertightness of the first internal space IS1 can be ensured. Therefore, it is possible to prevent the water level detection device 100 from breaking down.

  In addition, as long as the first internal space IS1 of the inner case 20 and the second internal space IS2 of the pipe 40 communicate with each other through the air introduction hole 20e, the air can be introduced into the first internal space IS1. Since it is possible, the arrangement position of the air introduction hole 20e is not particularly limited. Therefore, in the present embodiment, the air introduction hole 20e can be formed in the side surface 20a of the inner case 20.

  In particular, in water level detecting device 100 according to the present embodiment, gap 22 formed between the outer peripheral surface of inner case 20 and the inner peripheral surface of first tubular member 11 of outer case 10 is formed by the second gap of pipe 40. 2 with the internal space IS2. Accordingly, by forming the air introduction hole 20e at a position where the gap 22 and the first internal space IS1 of the inner case 20 can communicate with each other, the first internal space IS1 and the second internal space IS are substantially formed. It can communicate with IS2. Thereby, air can be introduced from the second internal space IS2 to the first internal space IS1 through the gap 22 and the air introduction hole 20e.

  However, when the water level detection device 100 is attached so as to be perpendicular to the side wall of the bathtub 200 as in the present embodiment, as shown in FIG. Is also preferably formed at an upper height position.

  The first reason is that the higher the height position of the air introduction hole 20e, the more difficult it is for the air introduction hole 20e to contact the bathtub water flowing into the inside of the pipe 40. Even when bathtub water flows into the pipe 40, the first internal space IS1 of the inner case 20 can be opened to the atmosphere by making it difficult for the bathtub water to contact the air introduction hole 20e. Thereby, while ensuring the watertightness of the first internal space IS1, it is possible to suppress a decrease in the detection accuracy of the water level detection device 100.

  Second, when the air introduction hole 20e is formed at a height lower than the through hole 20d, the bathtub water is accumulated in the second internal space IS2 of the pipe 40, and the bathtub is inserted into the air introduction hole 20e. This is because the possibility of inflow of water increases. Therefore, when the air introduction hole 20e is formed at a height position below the through hole 20d, the air introduction hole 20e is formed at a height position above the through hole 20d. It is required to make the opening diameter smaller.

  In other words, with the configuration in which the air introduction hole 20e is formed at a height position higher than the through hole 20d, compared with the configuration in which the air introduction hole 20e is formed at a height position lower than the through hole 20d, The effect of suppressing a decrease in the detection accuracy of the water level of the bathtub 200 due to the bathtub water flowing into the pipe 40 can be enhanced. In addition, since the opening diameter of the air introduction hole 20e can be increased, there is an advantage that it can be easily formed.

  In water level detecting apparatus 100 according to the present embodiment, gap 22 between the outer peripheral surface of inner case 20 and the inner peripheral surface of first cylindrical member 11 of outer case 10 is formed through first air introduction hole 20e. It communicates with the space IS <b> 1 and one end thereof is closed by the second tubular member 12. Therefore, the gap 22 has a structure in which air can be kept. With such a structure, as shown in FIG. 7, even when bathtub water is stored in the second internal space IS2 of the pipe 40, air is interposed between the bathtub water and the air introduction hole 20e. It will be. Thereby, the bathtub water can be prevented from contacting the air introduction hole 20e, so that the effect of ensuring the watertightness of the first internal space IS1 of the inner case 20 can be enhanced.

(Modification)
In the above-described embodiment, the housing member that houses the water level sensor unit 30 has the double structure including the outer case 10 and the inner case 20. However, even when the housing member has a single structure, the water level detection according to the above-described embodiment is possible. The same effect as the device 100 can be obtained.

  Hereinafter, the configuration of the water level detecting device according to the modified example of the present embodiment will be described. Note that the basic configuration of the water level detecting device according to the present modified example is the same as that of the water level detecting device 100 according to the present embodiment except for the housing member, and thus the description thereof will be omitted.

  FIG. 8 is a cross-sectional view schematically showing a configuration of water level detecting device 100 according to the present modification of the present embodiment, and is a diagram compared with FIG. Referring to FIG. 8, the present modification is different from the embodiment in that a case 60 is provided instead of first cylindrical member 11 and inner case 20.

  The case 60 has a side surface portion 60a, a bottom surface portion 60b, and a tubular portion 60c extending from the bottom surface portion 60b to the pipe 40 side. The side surface portion 60a has, for example, a cylindrical shape. The bottom portion 60b has, for example, a disk shape. The bottom surface portion 60b is disposed so as to cover the opening of the side surface portion 60a on the side opposite to the water receiving chamber 10a. The tubular portion 60c is connected to one end of the pipe 40. Case 60 is formed of, for example, stainless steel.

  The support member 14 is attached to the case 60 so as to cover an opening of the side surface portion 60a on the water receiving chamber 10a side. The support member 14 is fixed to the case 60 by a plurality of screws 150. An inner sealing member (not shown) is arranged between the support member 14 and the case 60. The inner sealing member is configured to seal a gap between the support member 14 and the case 60.

  The case 60 has a water receiving chamber 10 a that can receive hot and cold water stored in the bathtub 200. The space surrounded by the second tubular member 12, the perforated plate 13, and the support member 14 constitutes the water receiving chamber 10a. The water receiving chamber 10a is configured to receive bathtub water from the plurality of through holes 13a of the perforated plate 13.

  The water level sensor unit 30 is housed in the first internal space IS1 of the case 60. The water level sensor unit 30 is configured to be able to detect the water pressure of the water receiving chamber 10a. The water level sensor unit 30 is fixed to the support member 14 by screws (not shown). The tip of the water level sensor unit 30 is inserted into a through hole 14a formed in the center of the support member 14.

  A through hole 60 d for drawing out the output signal line 70 to the outside of the case 60 is formed in the bottom surface portion 60 b of the case 60. The output signal line 70 extends from the first internal space IS1 of the case 60 to the second internal space IS2 of the pipe 40 through the through hole 60d. The sealing member 50 is disposed between the outer peripheral surface of the output signal line 70 and the through hole 60d. The sealing member 50 is configured to seal a gap between the outer peripheral surface of the output signal line 70 and the through hole 60d in a watertight manner.

  At the bottom portion 60b of the case 60, an atmosphere introduction hole 60e for introducing the atmosphere into the first internal space IS1 is further formed. The air introduction hole 60e communicates the first internal space IS1 with the second internal space IS2. The opening diameter of the air introduction hole 60e is large enough to prevent bathtub water from entering the first internal space IS1 so as not to impair the watertightness of the first internal space IS1. For example, the opening diameter of the air introduction hole 60e can be about 1 to 2 mm.

  With this configuration, if the air introduction hole 60e is not in contact with the bathtub water, the first internal space IS1 of the case 60 is opened to the atmosphere through the air introduction hole 60e. The water level of the hot water stored in the water can be accurately detected.

  When bathtub water flows into the pipe 40 and the air introduction hole 60e comes into contact with the bathtub water, the first internal space IS1 cannot be opened to the atmosphere, but the first internal space IS1 cannot be opened to the atmosphere. By preventing bathtub water from entering the internal space IS1, it is possible to ensure watertightness of the first internal space IS1. Therefore, it is possible to prevent the water level detection device 100 from breaking down.

  In water level detection apparatus 100 according to the present modification, similarly to water level detection apparatus 100 according to the embodiment, it is preferable that air introduction hole 60e is formed at a height position higher than through hole 60d.

  The embodiments disclosed this time are to be considered in all respects as illustrative and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  Reference Signs List 10 outer case, 10a water receiving chamber, 11 first cylindrical member, 11a large diameter portion, 11b medium diameter portion, 11c small diameter portion, 11d, 11e wall portion, 12 second cylindrical member, 13 eye plate, 14 Support member, 15 communication member, 15a internal space, 20 inner case, 20a, 60a side surface portion, 20b, 60b bottom surface portion, 20c flange portion, 20d, 60d through hole, 20e, 60e air introduction hole, 22 gap, 30 water level sensor Unit, 30a pressure sensor, 30b housing, 30c pressure introduction hole, 30d oil passage, 30e protection member, 30f output terminal, 35 relay board, 40 piping, 42 water cutter, 50 sealing member, 60c cylindrical portion, 70 output signal Wire, 71 cladding tube, 72 wiring member, 100 water level detection device, 110, 140, 150, 160 Di, 200 bathtubs, 201 waterproof layer, 300 hot water, 400 control unit, IS1 first internal space, IS2 second internal space.

Claims (6)

A water level detection device that detects a water level of water stored in the bathtub while being installed on a side wall of the bathtub,
A housing member having an internal space separated from the bathtub,
A pressure sensor housed in the internal space of the housing member and capable of detecting a water pressure of the bathtub,
A signal line electrically connected to the pressure sensor,
The housing member has a through hole for drawing out the signal line from the internal space to the outside of the housing member, and the through hole is sealed in a watertight manner,
The housing member further has an air introduction hole,
The water level detection device, wherein the air introduction hole is configured to seal the internal space in a watertight manner and to introduce air into the internal space . Inside the side wall, a pipe for drawing the signal line to the outside of the side wall is embedded.
The housing member is configured to be installed on the side wall by connecting the signal line to the pipe while being inserted through the pipe,
The water level detection device according to claim 1, wherein the air introduction hole is formed so as to communicate the internal space of the housing member and the inside of the pipe.   The water level detection device according to claim 1, wherein the air introduction hole is formed at a height position higher than the through hole.   The water level detecting device according to claim 2, wherein the air introduction hole is formed at a height position higher than the pipe. The housing member,
An inner case that houses the pressure sensor;
An outer case that houses the inner case,
The through hole and the air introduction hole are formed in the inner case,
A gap is formed between the outer peripheral surface of the inner case and the inner peripheral surface of the outer case, which communicates the inside of the inner case and the outside of the outer case through the air introduction hole and contains air. The water level detecting device according to any one of claims 1 to 4.   The water level detection device according to claim 1, further comprising a sealing member attached between an outer peripheral surface of the signal line and the through hole.

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