JPH11169018A - Waterproof heater device and water tank with heater - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a waterproof heater device and a water tank with a heater that can maintain a water temperature at an appropriate temperature with a simple and inexpensive configuration. Provided are a waterproof heater device and a heater-equipped water tank that can uniformly heat water in the water tank. The inside of a water tank with a heater is partitioned by a partition plate into a rearing room and a pump room. A concave portion 2a is formed on the upper surface of the bottom portion 2 of the water tank 1, and the concave portion 2a has a heater unit H including a heat radiating plate 8 and a plurality of heaters 9 disposed on the lower surface 8a of the heat radiating plate 8. Is fitted. The heater 9 has a built-in PTC heating element. A heating chamber 11 is formed below the heater unit H. The heating room 11 is configured such that water can freely enter and leave between the breeding room 6 and the pump room 7. A submersible pump 17 is provided in the pump chamber 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waterproof heater device used to heat water in a water tank, for example. Further, the present invention relates to a heater-equipped water tank provided with a heater for heating water in the water tank.

[0002]

2. Description of the Related Art Conventionally, when breeding tropical fish or saltwater fish in an aquarium, it is necessary to maintain the temperature of the water in the aquarium at an appropriate temperature using a heater device or the like in order to optimize the environment for these fish. Is being done. As a heater device used for heating water in a water tank, for example, a heating element such as a nichrome wire is housed inside a cylindrical member, and both ends of the cylindrical member are sealed with rubber caps or the like. The stopped one is known (for example, Japanese Patent Application Laid-Open No. 9-65797,
JP-A-9-65798 and JP-A-9-2832
No. 67). This heater device can heat the water in the water tank by supplying electric power to the heating element while being immersed in the water.

[0003]

However, in the above-described heater device, a heating temperature control circuit including a thermostat, a thermistor, or the like is used to maintain the heating temperature of the heating element at a predetermined temperature and prevent abnormal overheating of the heating element. And the cost of the heater device is increased. In a heater device having a thermostat, if a contact failure of the thermostat occurs,
The exothermic temperature could not be controlled well, and the water temperature could rise abnormally.

Further, the above-described conventional heater device is used, for example, in a state where it is placed on the bottom of a water tank or on gravel spread all over the bottom of the water tank (Japanese Patent Laid-Open No. 9-657).
No. 97 and FIG. 1 of Japanese Patent Application Laid-Open No. 9-283267), there has been a problem that the water temperature around the heater device becomes relatively high and the water temperature in the water tank becomes uneven.

Accordingly, an object of the present invention is to provide a waterproof heater device and a water tank with a heater which can maintain the water temperature at an appropriate temperature with a simple and inexpensive configuration. Another object of the present invention is to provide a waterproof heater device and a heater-equipped water tank that can uniformly and well heat water in the water tank.

[0006]

According to a first aspect of the present invention, there is provided a heater having a plurality of heaters formed by waterproofly covering a positive temperature coefficient thermistor element with a synthetic resin covering member. A junction member made of synthetic resin for waterproofly covering a connection portion between a power supply line extending from the plurality of heaters and a power cord to be connected to a power supply, and the plurality of heaters and the junction member are attached. And a heat radiating plate for transmitting heat generated from the plurality of heaters and radiating heat from the surface.

[0007] According to this configuration, the positive temperature coefficient thermistor element is waterproofly covered with a covering member made of synthetic resin. Further, a connection portion between the power supply line extending from the plurality of heaters and the power cord is waterproofly covered with a junction member made of synthetic resin. Therefore, this waterproof heater device does not cause a short circuit due to moisture or the like at the heater portion or the connection portion between the power supply line and the power cord, and can have high reliability for use underwater.

In addition, the positive temperature coefficient thermistor element undergoes a crystal phase transition between a ferroelectric substance and a paraelectric substance near a predetermined Curie temperature, thereby changing the resistance value of the element itself and further increasing the resistance value above the Curie temperature. As a result, a transition from a conductor to an insulator occurs. Therefore, when the temperature of the element itself rises above the Curie temperature, the amount of current flowing through the element decreases, and the amount of heat generated by the element decreases. Thereby, the element temperature can be maintained at a constant temperature.

Therefore, if a positive temperature coefficient thermistor element is used as the heating element, there is no need to provide a sensor for detecting the heating temperature or a heating temperature control circuit in order to control the heating temperature. Can be reduced in initial cost and running cost. In addition, since the positive temperature coefficient thermistor element does not generate heat above a certain temperature, when this waterproof heater device is used to heat the water in the water tank, the water temperature in the water tank can always be maintained at an appropriate temperature. it can. Moreover, since no space is required for sensors and control circuits, the water tank can be used effectively.

When the waterproof heater device is used to heat water in a water tank, the size of the heat radiating plate is formed to be substantially the same as the size of the bottom surface of the water tank, and the size of the heater is adjusted according to the volume of the water tank. By increasing or decreasing the number of the water heaters and the number of the junction members, the water in the water tank can be heated substantially uniformly even when the waterproof heater device is placed on the bottom surface of the water tank.

The invention according to claim 2 is a water reservoir having a bottom and a peripheral side surface rising from the periphery of the bottom and capable of storing water therein, a heating chamber provided at the bottom, and the water reservoir. And a communication passage communicating the water reservoir and the heating chamber so that water can flow between the heating chamber and the heating chamber, and a positive-characteristic thermistor element covered with a synthetic resin coating provided in the heating chamber. And a heater formed by waterproof coating with a member.

According to this configuration, the water in the heating chamber provided separately from the water reservoir is heated by the heat generated by the heater. Since the heating chamber is provided below the water reservoir, the water heated by the heater flows into the water reservoir through the communication passage by natural convection. Therefore, the heater is immersed in the water in the water chamber, and the water in the water chamber is directly heated by the heat generated by the heater (Japanese Patent Laid-Open No. 9-65797).
(See FIG. 1 of Japanese Patent Application Laid-Open No. Hei 9-283267 and FIG. 1 of Japanese Patent Application Laid-Open No. 9-283267), there is no inconvenience that the water temperature around the heater becomes relatively high and the water temperature in the water storage chamber becomes uneven. .

Further, as in the first aspect of the present invention, since a heater having a PTC thermistor element is applied, no thermistor or thermostat for temperature control is required, and the initial cost of the water tank is reduced. can do. In addition, since the electric power required to maintain the water temperature at an appropriate temperature can be minimized, the running cost can be reduced. In addition, since the positive temperature coefficient thermistor element does not generate heat above a certain temperature, the water temperature in the water tank can always be kept at a suitable temperature.

Further, since the positive temperature coefficient thermistor element is waterproof-coated with a covering member made of synthetic resin, there is no short circuit due to moisture or the like in the heater portion. The invention according to claim 3 further includes a heat sink disposed on one side facing the heating chamber, wherein the heater is mounted on one surface of the heat sink facing the heating chamber. Item 2. A water tank with a heater according to Item 2.

According to this configuration, since the heater is attached to the radiator plate, the water in the heating chamber can be efficiently heated. When this water tank with a heater is used for rearing fish, the water reservoir is a rearing room for rearing fish, and a surface of the heat sink opposite to the surface on which the heater is attached is provided. It is preferable that the radiator is provided facing the pool (breeding room), and gravel is spread over the heat sink through a nonwoven fabric. In this case, the heat of the heater that propagates through the radiator plate is radiated from the surface of the radiator plate to indirectly heat the gravel through the nonwoven fabric, thereby promoting the activity of microorganisms having a water purification ability generated in the gravel. It is possible to improve the fish breeding environment.

According to a fourth aspect of the present invention, a plurality of the heaters are provided, and a connection portion between a power supply line extending from the plurality of heaters and a power supply cord to be connected to a power supply is made of synthetic resin. The water tank with a heater according to claim 3, wherein the water tank is covered with a waterproof by a junction member. According to this configuration, even when a plurality of heaters are provided, the connection portion between the power supply line extending from the plurality of heaters and the power supply cord is covered with the synthetic resin junction member. Therefore, a short circuit due to moisture or the like does not occur at the connection portion between the power supply line and the power supply cord.

According to a fifth aspect of the present invention, a pump chamber communicated with the heating chamber and the pump chamber are provided, and the water flowing into the pump chamber from the heating chamber is sucked up and discharged into the reservoir. The water tank with a heater according to any one of claims 2 to 4, further comprising a pump. According to this configuration, the water heated by the heat generated from the heater in the heating chamber flows into the pump chamber from the heating chamber by the action of the pump, is further sucked up by the pump, and is discharged into the reservoir. Therefore, since the water heated by the heat generated from the heater flows well through the inside of the water tank with the heater, it is possible to further eliminate a possibility that the water temperature in the water storage chamber becomes uneven.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below.
This will be described in detail with reference to the accompanying drawings. FIG. 1 is a perspective view showing a configuration of a water tank with a heater according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of the water tank as viewed from section line II-II in FIG. The water tank 1 with a heater is a water tank for breeding tropical fish, saltwater fish, and the like, and has a rectangular bottom portion 2 in a plan view, a peripheral side plate 3 provided in a state of rising from a peripheral edge of the bottom portion 2, and a peripheral tank. And an upper frame 4 attached to an upper edge of the side plate 3.

On the upper surface of the bottom 2, a left side plate 3 a of the peripheral side plate 3 is provided.
And a partition plate 5 extending in parallel with the right side plate 3b. A space defined by the bottom portion 2, the peripheral side plate 3 and the upper frame 4 is viewed in the direction of the arrow in FIG. The partition 5 is partitioned into a rearing room 6 as a water reservoir on the left side of the partition plate 5 and a pump room 7 on the right side of the partition plate 5. The fish to be bred is bred in a breeding room 6, and the peripheral plate 3 is made of a transparent synthetic resin or glass so that the fish in the breeding room 6 can be seen from the outside. ing.

The portion of the upper surface of the bottom 2 facing the rearing room 6 includes:
A rectangular recess 2a is formed in plan view.
A heater unit H as a waterproof heater device for heating water contained in the water tank 1 is fitted into the recess 2a. The heater unit H has a flat rectangular heat radiating plate 8 and a plurality of heaters 9 arranged on the lower surface of the heat radiating plate 8. The heater unit H includes a heat sink 8
Is locked to a step portion 10 formed in the middle of the peripheral surface of the concave portion 2a, whereby a heating chamber 11 is formed below the heater unit H.

A non-woven fabric 12 formed in a flat rectangular shape having substantially the same size as the heat radiating plate 8 is fitted into the concave portion 2a. The nonwoven fabric 12 is provided with the heater 9 of the heat sink 8.
Is almost in contact with the surface opposite to the surface on which
Gravel 13 is spread on it. The heating chamber 11 formed in the bottom 2 is communicated with the breeding room 6 by an inflow passage 15 extending from a slit 14 formed on the left side of the concave portion 2a when viewed in the direction of the arrow in FIG.
The distribution of water between is free. In addition, heating room 1
1 is communicated with the pump chamber 7 by an outflow channel 16 extending from a surface facing the surface to which the inflow channel 15 is connected, so that water can freely enter and leave the pump chamber 7. ing.

A submersible pump 17 that can be used underwater is provided in the pump chamber 7. Submersible pump 1
Reference numeral 7 is attached to the right side plate 3b of the peripheral side plate 3, and is provided with its suction port 17a directed downward.
A discharge pipe 18 is connected to a discharge port 17 b of the submersible pump 17, and a distal end of the discharge pipe 18 is inserted into a hole 5 a formed in the partition plate 5 and faces the breeding room 6. Therefore, by driving the submersible pump 17, the water in the pump room 7 is pumped up and the pumped water is fed to the breeding room 6.
Can be discharged inside.

With the above structure, the heat generated from the heater 9 is radiated from the heater 9 itself and the heat radiating plate 8
And the heat is radiated from the lower surface of the heat radiating plate 8 and
The water inside warms up. The warmed water in the heating chamber 11 flows out of the heating chamber 11 to the pump chamber 7 by natural convection and the action of the submersible pump 17. Then, the water is sucked up by the submersible pump 17 and discharged to the breeding room 6 via the discharge pipe 18. Thereby, the water heated by the heater unit H is mixed into the water in the breeding room 6, and as a result, the water temperature in the breeding room 6 rises. Further, the cold water in the breeding room 6 is supplied to the slit 1
The heating unit 11 flows into the heating chamber 11 through the inlet 4 and the inflow path 15 and is heated by the heater unit H.

FIG. 3 is a view showing the configuration of the heater unit H, as viewed from the heating chamber 11 side. As described above, the heater unit H has the flat rectangular heat radiating plate 8 and the plural (12 in this embodiment) heaters 9 disposed on the lower surface of the heat radiating plate 8. The heater units H are also arranged in parallel at substantially equal intervals in the vertical direction at the center in the horizontal direction of the heat sink 8 in FIG.
It has junction members 19, 20, 21.

The twelve heaters 9 are arranged two on each of the right and left sides of each of the junction members 19, 20, and 21, and are fixed to the lower surface of the heat radiating plate 8 by, for example, an adhesive. Each junction member 19, 20, 2
A total of four heaters 9 arranged two on each of the left and right sides of 1
Are connected in parallel to each other at a pair of connection terminals (described later) provided inside the junction members 19, 20, and 21, respectively. The connection terminals in the junction member 19 and the connection terminals in the junction member 20 are connected in parallel by connection cords 22a and 22b, and the connection terminals in the junction member 20 and the connection terminals in the junction member 21 are connected to each other. , Connection code 2
3a and 23b are connected in parallel. Thus, when a voltage is applied to the heater unit H from the commercial AC power supply (not shown) via the power cords 24 and 25, the voltage is applied in parallel to the twelve heaters 9 included in the heater unit H. become.

FIG. 4 is a plan view showing the heater 9 partially cut away. FIG. 5 is a cross-sectional view of the heater 9 taken along the line VV in FIG. The heater 9 is a PTC (Positive TTC) made of a ceramic semiconductor having PTC characteristics.
emperature Coefficient). In addition, the heater 9 includes an upper power supply member 27 and a lower power supply member 28 which are disposed oppositely above and below the PTC heating element 26. PTC heating element 26 and power supply member 2
The heat generating unit including the heat generating units 7 and 28 is sealed by an upper insulating case 30 and a lower insulating case 31 as covering members having electrical insulation while the cap 29 is covered.

The PTC heating element 26 is made of barium (B
a), strontium (Sr), calcium (Ca),
It is obtained by sintering a raw material containing titanium (Ti), manganese (Mn), dysprosium (Dy), silicon (Si), etc. by a general ceramic method. ) Is a heat-sensitive element that has a low resistance, but has a characteristic that the resistance value suddenly increases when the temperature exceeds the Curie temperature. Due to this characteristic, the PTC heating element 26
When a voltage is applied at a temperature lower than the Curie temperature, a large current flows because the resistance is small because the temperature is low at first, and the temperature of the PTC heating element 26 rises rapidly. When the temperature of the PTC heating element 26 exceeds the Curie temperature, the amount of current decreases because the resistance value suddenly increases, and as a result, the heating value of the PTC heating element 26 decreases. Therefore, the temperature of the PTC heating element 26 does not rise above a certain temperature, and the thermal equilibrium state is stably maintained at a certain temperature. That is, the PTC heating element 26 is
It has a self-temperature control function.

The PTC heating element 26 is formed in a flat cylindrical shape as a whole.
2 are formed through the upper and lower surfaces. The mounting hole 32 is
The positioning shaft 33 formed on the lower insulating case 31 is formed in a size that can be inserted. Electrodes 34 and 35 are formed on the upper and lower surfaces of the PTC heating element 26, respectively. The electrodes 34 and 35 can be fired by applying a silver paste for forming an ohmic contact electrode and a cover to the PTC heating element 26 and then heating the PTC heating element 26 at 560 ° C. for 5 minutes. it can.

The Curie temperature, element resistance, temperature coefficient, power consumption, etc. of the PTC heating element 26 can be changed by changing the material composition of the PTC heating element 26 and the firing conditions (firing temperature and firing time), By changing the shapes and areas of the electrodes 34 and 35 formed on the heating element 26, the electrodes 34 and 35 can be arbitrarily changed within an appropriate range.
For example, the Curie temperature of the PTC heating element 26 is P
By changing the material composition of the TC heating element 26, -5
It can be changed to any temperature value within the range of 0 ° C to 350 ° C.

In this embodiment, the Curie temperature of the PTC heating element 26 is preferably set to a temperature at which the water temperature of the breeding room 6 shown in FIG. 1 is stable within the range of 20 ° C. to 30 ° C. . Further, it is more preferable that the water temperature of the breeding room 6 is set to be stable within a range of 23 ° C. to 27 ° C. The upper power supply member 27 includes a disc portion 27a and a connection portion 27b formed on the same plane as the disc portion 27a.
And are integrally formed of a conductive metal thin plate. Also, the lower power supply member 28 is
a and the connecting portion 28b, and are integrally formed of a conductive metal thin plate. Disk portion 27a,
Reference numeral 28a is formed to have a size substantially equal to the outer diameter of the PTC heating element 26.
The mounting holes 24 and 25 having substantially the same diameter as the mounting hole 32 formed in the C heating element 26 are formed through.

The power supply members 27 and 28 are arranged such that the disk portion 27a of the upper power supply member 27 contacts the electrode 34 and the disk portion 28a of the lower power supply member 28 contacts the electrode 35. At this time, the connection portion 27b of the upper power supply member 27 and the connection portion 28b of the lower power supply member 28 are parallel to each other and are shifted from each other in the facing direction. On the lower surface side of the connection portion 27b of the upper power supply member 27, the other end of the power supply line 36 whose one end is connected to the connection member in the junction members 19, 20, 21 is connected by soldering. Further, the other end of the power supply line 37 whose one end is connected to the connection terminal in the junction members 19, 20, 21 is connected to the upper surface side of the connection portion 28b of the lower power supply member 28 by soldering. Thereby, each junction member 19, 2
Power supplied to the connection terminals in the
6, 37, the power supply members 27, 28 and the electrodes 34, 35 to the PTC heating element 26.

The cap 29 is for fixing the power supply members 27 and 28 in contact with the electrodes 34 and 35, respectively, and is integrally formed of an electrically insulating material. The cap 29 is a PTC heating element 26
A space is formed inside and the lower surface is open so that the power supply members 27 and 28 can be covered from above. Also, a PT is provided on the upper surface of the cap 29 at the center thereof.
A mounting hole 38 having substantially the same diameter as the mounting hole 32 formed in the C heating element 26 is formed therethrough. Furthermore, cap 2
A cutout 29a is formed on the side surface of the connector 9 to allow the connection portions 27b and 28b to protrude.

The power supply members 27 and 28 and the electrodes 34 and 3
The connection with 5 may be performed using an adhesive having conductivity. However, in consideration of the time required for curing the adhesive and the trouble of preventing short circuit between the upper electrode 34 and the lower electrode 35 due to the dripping of the adhesive, as described above, the cap 29 may be used without using the adhesive. By putting on
It is preferable to fix the power supply members 27 and 28 to the electrodes 34 and 35, respectively.

The lower insulating case 31 is formed, for example, by injection molding using a synthetic resin material having electrical insulation. The lower insulating case 31 is provided with a substantially cylindrical positioning shaft 33 protruding in a standing state in FIG. The PTC heating element 26, the power supply members 27 and 28, and the cap 29 are attached to the mounting hole 25 of the lower power supply
The positioning shaft 33 is inserted through the mounting hole 32 of the C heating element 26, the mounting hole 24 of the upper power supply member 27, and the mounting hole 38 of the cap 29 in this order, thereby positioning the lower insulating case 31. . Also, the positioning shaft 33
In addition to the adhesive described above, a hole 39 for fixing the heater 9 to the heat radiating plate 8 using a bolt (not shown) or the like is formed.

The upper insulating case 30 is composed of the PTC heating element 2
6 and the power supply members 27 and 28 are attached to the lower insulating case 31, and the lower insulating case 31 is set in an injection molding die with the cap 29 covered, and a synthetic resin material having electrical insulation is injection molded. By doing so, it is formed integrally with the lower insulating case 31. Therefore, the PTC heating element 26, the power supply members 27, 28, and the connection portions between the power supply members 27, 28 and the power supply lines 36, 37 are waterproofed and sealed by the upper insulating case 30 and the lower insulating case 31. Therefore, the heater 9 has no risk of short circuit due to moisture or the like.

Upper insulating case 30 and lower insulating case 31
Has low heat shrinkage, good heat conduction, heat resistance to withstand heat change, waterproofness that does not allow moisture to pass through inside, and airtightness that does not allow air to pass inside. Is preferably made of a material having good adhesion. Accordingly, examples of the material of the insulating cases 30 and 31 include a polymer alloy made of nylon, polypropylene, and glass fiber.

The upper insulating case 30 and the lower insulating case 3
It is desirable from the viewpoint of integration that 1 and 1 are made of the same material since they have good affinity for each other and have the same thermal expansion coefficient. FIG. 6 is an enlarged perspective view showing the configuration of the junction member 20. Three junction members 19, 20, 2 provided in the heater unit H
1 has almost the same configuration, and the following describes the configuration by taking the junction member 20 as an example.

The junction member 20 is connected to the connection cord 2
2a, 22b and 23a, 23b and feeder lines 36, 37
And a junction body member 40 and a junction lid member 41 formed of a synthetic resin. FIG. 7 is a plan view showing the configuration of the junction body member 40. The junction body member 40 is formed in a flat bottomed cylindrical shape, and a columnar convex portion 42 is provided upright at the center of the bottom surface. On the bottom surface of the junction main body member 40, an outer annular rib 43 is provided on a peripheral portion thereof, and an inner annular rib 44 is erected between the outer annular rib 43 and the projection 42. Between the convex portion 42 and the inner annular rib 44,
An annular inner connection terminal 45 is disposed, and an inner annular rib 45 is provided.
Between the outer annular rib 44 and the annular outer connection terminal 4.
6 are arranged.

The outer annular rib 43 is provided with feed line introduction recesses 47 and 48 for introducing feed lines 36 and 37 extending from the heater 9 into the inside, respectively, at four locations. Correspondingly, the inner annular rib 44 is provided with four feed line introduction concave portions 49 for introducing one feed line 36 to the position of the inner connection terminal 45. Further, the outer annular rib 43 is used to introduce the connection cords 22a, 22b connected to the connection terminals in the junction member 19 and the connection cords 23a, 23b connected to the connection terminals in the junction member 21, respectively. Connection cord introduction recess 50 and connection cord introduction recess 5
1 corresponding to the inner annular rib 4
4, a connection cord introduction recess 52 and a connection cord introduction recess 53 for introducing the connection cords 22a and 23a to the position of the inner connection terminal 45, respectively, are formed.

The power supply line 36 of each heater 9 is connected to the junction main body member 40 through a power supply line introduction concave portion 47 of the outer annular rib 43 and a power supply line introduction concave portion 49 of the inner annular rib 44.
And its tip is soldered and connected to the inside connection terminal 45. The power supply line 37 of each heater 9 is introduced into the inside of the junction main body member 40 via the power supply line introduction concave portion 48 of the outer annular rib 43, and the tip is connected to the outer connection terminal 46.

The connection cord 22a is connected to the inside connection terminal 45 by soldering the tip through the connection cord introduction recess 50 and the connection cord introduction recess 52, and the connection cord 22b is connected via the connection cord introduction recess 50. The tip is soldered and connected to the outer connection terminal 46. The connection cord 23a is connected to the connection cord introduction recess 5.
1 and the connection cord introduction recess 53, the tip of which is soldered to the inside connection terminal 45 and connected. The connection cord 23b is soldered with the tip thereof to the outside connection terminal 46 via the connection cord introduction recess 50. Being connected.

On the other hand, the junction cover member 4 shown in FIG.
Numeral 1 is formed in a disc shape corresponding to the junction body member 40, and the connection terminals 22a and 22b, the connection lines 23a and 23b, and the power supply lines 36 and 37 are connected to the connection terminals 4a and 4b.
The junction member 20 is formed by being fitted to the upper end of the junction main body member 40 in a state (the state shown in FIG. 7) connected to the junction members 5 and 46. The junction member 20 includes a junction body member 40.
A resin (for example, a silicone resin) having a waterproof property and an electric insulation property is filled from the resin filling opening 54 formed in the substrate. Thereby, in the junction member 20, the connection cords 22a and 22b, the connection cord 23
The lead portions a and 23b, the lead-out portions of the feed lines 36 and 37, and the connection terminals 45 and 46 are sealed with resin. Therefore,
Since no moisture or the like enters the junction member 20, there is no possibility that a short circuit will occur due to the entered moisture or the like.

The junction member 19 has no connection cord introduction recesses 51, 53 for introducing the connection cords 23a, 23b, and the connection terminals 45, 46 have connection cords 22a, 22b and respective connection cords. Feeding lines 36 and 37 extending from the heater 9 are connected.
In addition, as for the junction member 21, the connection cord introduction recess 5 for introducing the connection cords 22a and 22b is provided.
A power cord introduction recess for introducing the power cords 24 and 25 is formed in place of the connection terminals 4 and 25.
5 and 46 include connection cords 23a and 23b, power cords 24 and 25, and power supply lines 36 and 3 extending from each heater 9.
7 is connected.

As described above, according to the present embodiment, the PTC
Heating element 26, power supply members 27 and 28, and power supply member 2
The connection portions between the power supply lines 36 and 37 and the power supply lines 36 and 37 are waterproofly covered with an upper insulating case 30 and a lower insulating case 31 as covering members. The inside of the junction members 19, 20, 21 for connecting a plurality of (four in this embodiment) heaters 9 in parallel is filled with resin, and the junction members 19, 20, 21 are filled.
There is no infiltration of moisture into the interior. Therefore, the above-described heater unit H can have high reliability for use in water.

Further, since the PTC heating element 26 having a self-temperature control function is used as the heating element, a heating temperature control circuit including a thermostat and a thermistor is not required to control the heating temperature. H cost is reduced. In addition, since the PTC heating element 26 does not generate heat above a certain temperature, there is no possibility that the water temperature becomes high due to abnormal heating of the PTC heating element 26.

Further, in the present embodiment, the water in the heating chamber 11 provided separately from the breeding room 6 is heated by the heat generated from the heater unit H, and the heated water is supplied to the submersible pump 1.
By the function of 7, it is made to flow into the breeding room 6. Therefore, a configuration in which the heater is immersed in the water in the breeding room and the water in the breeding room is directly heated by the heat generated from the heater (see FIG. 1 of JP-A-9-65797 and FIG. 1 of JP-A-9-283267). Unlike 1), the water in the breeding room 6 does not become locally hot,
The possibility that the water temperature in the breeding room 6 becomes uneven can be eliminated.

The heat generated by the heater 9 propagating through the heat radiating plate 8 is radiated from the upper surface of the heat radiating plate 8 to indirectly heat the gravel 13 via the nonwoven fabric 12, whereby the water quality naturally generated in the gravel 13 is increased. The activity of microorganisms having purification ability is promoted, and the environment for raising fish can be improved. Note that P
The material composition of the TC heating element 26 is barium,
The composition is not limited to strontium, calcium, titanium, manganese, dysprosium and silicon, and may be any composition as long as barium titanate is used as a main raw material and the produced PTC heating element 26 has PTC characteristics.

The number of the PTC heating elements 26 can be variously changed according to the capacity of the breeding room 6. Further, the number of heater units H is not limited to one, and a plurality of heater units may be provided according to the size of the water tank 1. Furthermore, the size of the heater unit H (radiator plate 8) is
Of the heater unit H
By increasing or decreasing the number of heaters 9 and the number of junction members 20 according to the size of the heater unit H
The water in the breeding room 6 can be heated substantially uniformly even when the garbage is placed on the bottom surface of the breeding room 6. Also in this case, since each of the heaters 9 and the junction member 20 has excellent waterproof performance, there is no possibility that a problem such as a short circuit due to moisture occurs in each of the heaters 9 and the junction member 20.

In addition, various design changes can be made within the scope of the technical matters described in the claims.

[0050]

Next, a more specific example will be described.
An electrode was formed by baking an ohmic silver paste and a silver paste for a cover on the upper and lower surfaces of a PTC heating element having an outer diameter of 15 mm, an inner diameter of 5.1 mm, and a thickness of 2.6 mm. Then, with the power supply member in contact with each electrode, the PTC heating element and the power supply member were electrically insulated and coated with a polymer alloy to prepare a heater. The 12 heaters thus formed were fixed to an aluminum heat transfer plate having a length of 345 mm, a width of 230 mm, and a thickness of 11 mm to obtain a heater unit. Using the heater unit thus prepared, a water tank with heater shown in FIGS. 1 and 2 was obtained. This water tank with a heater has a width (length in the left-right direction in the direction of the arrow in FIG. 1) of 400 mm, a depth (length in the front-rear direction in the direction of the arrow in FIG. 1) of 250 mm, and a height of 460 mm. ,
The discharge rate of the pump provided in the water tank with a heater is 8 liters per minute.

The average heat transfer coefficient in water of the water tank with heater thus prepared is about 47 W / (m) since the width of the water tank is 400 mm and the discharge rate of the pump is 8 liters per minute.
² · K). Therefore, the water temperature of the water in this tank 1
Since the inflow heat required to raise 5 ° C. to the water temperature of 25 ° C. is about 47 W, it can be seen that supplying 50 W of power to the heater unit H is sufficient.

When 50 W of electric power was supplied to the heater unit H, the water temperature in the water tank rose from 15 ° C. to 25 ° C., and it was confirmed that the water in the water tank (breeding room) was uniformly heated. Was. Also, after the water temperature rose to 25 ° C, the result was that the power consumption for maintaining the water temperature within the range of 25 ° C ± 2 ° C was about 9.4W, and the water temperature in the water tank rose to an appropriate temperature. After that, it was confirmed that the electric power supplied to the heater was small.

[0053]

According to the first aspect of the present invention, a short circuit due to moisture or the like does not occur in the heater portion or the connection portion between the power supply line and the power cord, and the device has high reliability for use in water. be able to. Also, since the positive temperature coefficient thermistor element does not generate heat above a certain temperature, when this waterproof heater device is used to heat water in a water tank,
The water temperature in the water tank can always be kept at an appropriate temperature. Moreover, since there is no need to provide a sensor for detecting the heat generation temperature or a heat generation temperature control circuit, it is possible to reduce the initial cost of the waterproof heater device. In addition, it is possible to minimize the electric power required to maintain the heat generation temperature at an appropriate temperature, and to reduce the running cost.

Further, when used for heating the water in the water tank, the size of the heat radiating plate is formed to be substantially the same as the size of the bottom surface of the water tank, and the number of heaters and junction members according to the volume of the water tank. By increasing or decreasing the number of, even when the waterproof heater device is placed on the bottom of the water tank,
The water in the water tank can be heated almost uniformly. According to the second aspect of the present invention, since the water in the heating chamber heated by the heater flows into the water reservoir through the communication path by natural convection, the water in the water reservoir can be uniformly heated.

Further, since a heater having a positive temperature coefficient thermistor element is applied, a thermistor or a thermostat for temperature control is not required, and the initial cost of the water tank can be reduced. In addition, since the electric power required to maintain the water temperature at an appropriate temperature can be minimized, the running cost can be reduced. In addition, since the positive temperature coefficient thermistor element does not generate heat above a certain temperature, the water temperature in the water tank can always be kept at a suitable temperature.

Further, since the positive temperature coefficient thermistor element is covered with a synthetic resin covering member in a waterproof manner, a short circuit due to moisture or the like does not occur in the heater portion. According to the third aspect of the present invention, since the heater is attached to the radiator plate, the water in the heating chamber can be efficiently heated. According to the fourth aspect of the present invention, even when a plurality of heaters are provided, the connection portion between the power supply line extending from the plurality of heaters and the power cord is waterproof by the junction member made of synthetic resin. Since it is covered, a short circuit due to moisture or the like does not occur in the heater portion or the connection portion between the power supply line and the power cord.

According to the fifth aspect of the invention, the water heated by the heat generated from the heater in the heating chamber flows into the pump chamber from the heating chamber by the action of the pump, and is further sucked up by the pump to enter the water storage chamber. Discharged. Therefore, since the water heated by the heat generated from the heater flows well through the inside of the water tank with the heater, it is possible to further eliminate a possibility that the water temperature in the water storage chamber becomes uneven.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a configuration of a water tank with a heater according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of the aquarium taken along section line II-II in FIG.

FIG. 3 is a diagram illustrating a configuration of a heater unit.

FIG. 4 is a plan view showing a heater with a part cut away.

5 is a cross-sectional view of the heater as viewed from section line VV in FIG.

FIG. 6 is an enlarged perspective view showing a configuration of a junction member provided in the heater unit.

FIG. 7 is a plan view showing a configuration of a junction body member.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Water tank with a heater 2 Bottom part 3 Peripheral side plate (peripheral side surface) 6 Breeding room (water storage room) 7 Pump room 8 Heat sink 9 Heater 11 Heating room 14 Slit (communication path) 15 Inflow path (communication path) 16 Outflow path (communication path) 17) Submersible pump 19, 20, 21 Junction member 22a, 22b, 23a, 23b Connection cord (power cord) 24, 25 Power cord 26 PTC heating element (positive temperature coefficient thermistor element) 30 Upper insulating case (covering member) 31 Lower Insulation case (covering member) H Heater unit (waterproof heater device)

Claims (5)

[Claims] 1. A plurality of heaters formed by waterproofly covering a PTC thermistor element with a covering member made of a synthetic resin, a power supply line extending from the plurality of heaters, and a power cord to be connected to a power supply. A junction member made of a synthetic resin for waterproofly covering a connection portion with the radiator plate; and a radiator plate to which the plurality of heaters and the junction member are attached and which propagates heat from the plurality of heaters and radiates heat from the surface. A waterproof heater device comprising: 2. A water storage chamber having a bottom portion and a peripheral side surface rising from a peripheral edge of the bottom portion and capable of storing water therein, a heating room provided at the bottom portion, a water storage room and the heating room. A communication path for communicating the water reservoir and the heating chamber so that water can flow between the heating chamber and the heating chamber, wherein the PTC thermistor element is waterproof-coated with a synthetic resin covering member. A water tank with a heater, comprising: 3. The heating device according to claim 2, further comprising a radiator plate having one surface facing the heating chamber, wherein the heater is attached to one surface of the radiating plate facing the heating room. Water tank with heater. 4. A plurality of heaters are provided, and a connecting portion between a power supply line extending from the plurality of heaters and a power supply cord to be connected to a power supply is waterproof-coated with a junction member made of synthetic resin. The water tank with a heater according to claim 3, wherein: 5. A pump chamber communicated with the heating chamber, and a pump provided in the pump chamber for sucking water flowing into the pump chamber from the heating chamber and discharging the water into the reservoir chamber. 5. The method according to claim 2, wherein
A water tank with a heater according to any one of the above.