JP4584903B2 - Underwater heater - Google Patents

Description

  The present invention relates to an underwater heater used in an underwater immersion state in, for example, an aquarium fish tank.

  Conventionally, as this type of underwater heater, a heating wire is housed in a cylindrical heater tube closed at both ends, and the heating wire is energized and heated. When the water temperature exceeds the set value, power supply to the heating wire is stopped by a thermostat. By doing so, what is comprised so that the water temperature in a water tank may be controlled uniformly is known (refer patent document 1).

  By the way, in this kind of aquarium, it is desirable to slightly lower the water temperature at night (for example, about 2 ° C.) from the viewpoint of maintaining the rhythm of ecology such as appreciation fish and aquatic plants, and this is also recommended from the viewpoint of realizing energy saving. .

In this way, it is possible to set the night water temperature a little lower, equipped with a timer in the thermostat part, and by setting a time zone where the water temperature needs to be lowered in the timer, the water temperature is lowered by a certain value at night It is known.
JP-A-10-98980

  However, if the thermostat is equipped with a timer as described above, it is necessary to add a function to set a time zone in which the water temperature needs to be lowered, which complicates the configuration and increases the cost. It was. Further, since the sunset time varies depending on the season, the setting of the time zone for lowering the water temperature in the timer must be changed, for example, every season, which is troublesome.

  The present invention has been made in view of such a technical background, and an object of the present invention is to provide an underwater heater capable of lowering the water temperature at night without causing complicated structure and increased cost.

  In order to achieve the above object, the present invention provides the following means.

[1] a heater part having a heating wire;
When the water temperature is lower than a set value, power is supplied to the heating line, and when the water temperature is higher than a set value, a thermostat unit that performs water temperature control by stopping power supply to the heating line;
An optical sensor for detecting ambient brightness,
Based on the fact that the brightness detection value by the light sensor is smaller than the set value, the water temperature set value in the thermostat is lowered, and the brightness detection value by the light sensor is larger than the set value. Based on the above, the submersible heater is configured to increase the water temperature set value in the thermostat and return it to the original value.

  [2] The submersible heater according to item 1, wherein the thermostat unit is configured separately from the heater unit, and the optical sensor is provided in the thermostat unit.

  In the invention of [1], the water temperature is set because a thermostat is provided to supply power to the heating wire when the water temperature is lower than the set value, and to stop supplying power to the heating wire when the water temperature is higher than the set value. Temperature can be controlled.

  And at night, it is configured to lower the water temperature set value in the thermostat based on the fact that the brightness detection value by the light sensor has become smaller than the set value. Controlled by water temperature.

  Since the night water temperature can be lowered only by using an optical sensor capable of discriminating nighttime in this way, the structure can be simplified as compared with the configuration using a conventional timer. Also, since the time zone where the water temperature needs to be lowered is left to the detection of the optical sensor, it is compared with the conventional configuration using a timer that requires the addition of a function for setting the time zone where the water temperature needs to be lowered. Can be manufactured at a significantly lower cost.

  In addition, the use of the optical sensor is very convenient because it is not necessary to reset the time zone for lowering the water temperature every season when the sunset time changes as in the case of using a conventional timer.

  In the invention of [2], since the photosensor is provided in the thermostat portion arranged outside the water, the ambient brightness can be detected with higher accuracy and the structure can be simplified. There are advantages.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic side view showing an example of a usage state of an underwater heater according to an embodiment of the present invention.

  As shown in FIG. 1, the underwater heater includes a heater unit 1 that is immersed in water in a water tank M, and a thermostat unit 2. The thermostat unit 2 is configured separately from the heater unit 1, and is arranged outside the water tank M.

  A power cord 21 having a plug 220 connected to a commercial power source (not shown) is drawn out from the thermostat unit 2. The heater unit 1 and the thermostat unit 2 are connected by a heater unit side cord 210 of the power cord 21.

  FIG. 2 is a cross-sectional view showing a configuration of the heater unit 1. In the heater unit 1, for convenience of explanation, the side on which the heater unit side cord 210 is drawn is referred to as a base end, and the counter electrode side is referred to as a front end.

  In FIG. 2, reference numeral 10 denotes a heater tube constituting the outer shell of the underwater heater. The heater tube 10 includes a cylindrical glass heater tube main body 11, and both end openings in the length direction of the heater tube main body 11. Are each composed of a pair of cap members (seal members) 19 and 25 that seal each in a liquid-tight state.

  In addition to the coiled first heating wire 12 and second heating wire 13 that are formed to have the same length and constitute the built-in heating element, a thermal fuse 14 and the like are accommodated inside the heater tube body 11. . In addition, a thin plate-like heating wire support member 16 made of an insulating material is disposed inside the heater tube main body 11 in a manner along the length direction of the main body 11.

  The first heating wire 12 is arranged on one side of the heating wire support member 16 along the length direction, and the base end of the first heating wire 12 is on the heater portion side through one connection terminal 20a. It is electrically connected to one lead portion 210 a of the cord 210.

  Further, the second heating wire 13 is disposed on the other one surface side of the heating wire support member 16 in the longitudinal direction, and the base end of the second heating wire 13 is connected to the heater via the other connection terminal 20b. It is electrically connected to the other lead part 210 b of the part side cord 210.

  The two heating wires 12 and 13 are connected in series via the thermal fuse 14, thereby forming an energization circuit that goes around the power source (not shown) and the heating wires 12 and 13.

  The thermal fuse 14 is disposed on the distal end side of the heating wire support member 16, and both ends thereof are respectively connected to the distal ends of the first heating wire 12 and the second heating wire 13 via connection terminals 20c and 20d. Electrically connected.

  A base end portion (on the side of the power cord 21) of the heating wire support member 16 is cut out so as to be substantially U-shaped, and one side of the heater unit side cord 210 is cut into the U-shaped cutout portion (not shown). The heater part side cord 210 is positioned by inserting the lead part 210a. Further, the end portion of the heating wire support member 16 is formed in a substantially L shape, and a lead wire portion of the thermal fuse 14 is formed in a substantially horizontal V-shaped notch portion (not shown) formed in the L-shaped corner portion. Is hooked and folded back to the heating wires 12 and 13 side.

  The one cap member 19 is a seal member that seals the proximal end opening of the heater tube body 11, and is made of a silicone rubber molded body. The other cap member 25 is also a seal member that seals the opening at the front end of the heater tube body 11, and is made of a silicone rubber molded body.

  A cylindrical cord lead-out portion 22 is formed to project from the center of the end face of the cap member 19 on the base end side, and the heater-side cord 210 is inserted into a hole 22a of the cord lead-out portion 22. .

  In addition, the inside of the heater tube main body 11 in which the energization circuit is formed is filled with an insulating material 18 such as insulating sand covering the heating wires 12 and 13, while the inside of the heater tube main body 11 is partitioned. A temperature fuse storage space 15 is formed by being partitioned by a member 17. The thermal fuse 14 is disposed in the thermal fuse storage space 15.

  The partition member 17 is composed of two disc-like insulating felts 17 </ b> A and 17 </ b> B overlapped with each other, and is attached to the distal end portion of the heating wire support member 16.

  A water temperature sensor 26 is disposed on the proximal end side in the heater tube main body 11, and a signal detected by the water temperature sensor 26 is sent to the thermostat unit 2.

  Next, an example of a procedure for assembling the heater unit 1 will be briefly described.

  A first heating wire 12 and a second heating wire 13 connected in series via a thermal fuse 14 and a partition member 17 are arranged at a predetermined position of the heating wire support member 16, and this is placed in the heater tube main body 11. Insert and place.

  Next, after filling the insulating material 18 from the proximal end opening of the heater tube main body 11, the proximal end opening of the heater tube main body 11 is sealed with the cap member 19, and the power source is supplied from the hole 22 a of the power cord lead-out portion 22. Pull out the heater portion side cord 210 of the cord 21. The lead of the water temperature sensor 26 is also drawn out from the hole 22a of the power cord lead-out portion 22. Further, the end opening of the heater tube body 11 is also sealed with a cap member 25. As a result, the heater tube main body 11 is filled with the insulating material 18 from the partition member 17 to the proximal end side, and a thermal fuse accommodating space 15 is formed from the partition member 17 to the distal end side.

  3 and 4 are a partially cutaway plan view and a partially cutaway side view showing the structure of the thermostat portion 2, respectively.

  3 and 4, the thermostat section case 31 includes a box-shaped case main body 32 made of synthetic resin and having an open top surface, and a synthetic resin cover 33 covering the upper surface opening of the case main body 32.

  In the case 31, a wiring board 34 for a temperature control circuit, a water temperature setting device 35, a power switch 36 and the like are accommodated. The wiring board 34 is provided with a neon tube 37 as a pilot lamp for indicating an energization state (ON or OFF) to the heating wires 12 and 13 and an optical sensor 38 for detecting ambient brightness. . Reference numeral 39 denotes a heat radiating plate of the power switch 36.

  A display window (not shown) made of a transparent member is provided in the cover 33 at a position directly above the neon tube 37, and a light / dark detection window made of a transparent member in the cover 33 at a position directly above the optical sensor 38. (Not shown) is provided.

  A setting operation knob 40 is attached and fixed to the operation shaft 35a of the water temperature setting device 35. By operating the operation knob 40, the control temperature of the water W in the water tank M can be set. It has become.

  FIG. 5 is a block diagram showing an electrical configuration of the thermostat unit 2. As shown in FIG. 5, the thermostat unit 2 includes a set water temperature holding control unit 51 and a night set water temperature change control unit 52.

  The set water temperature holding control unit 51 compares a detection output from the water temperature setting unit 35 including the water temperature setting unit, a detection output from the water temperature detection unit 26 including the water temperature sensor, and an output from the water temperature setting unit 35. The comparator 53 and the power switch 36 are included.

  The first comparator 53 compares the detected value by the water temperature detecting unit 26 with the set value of the water temperature setting unit 35, and when the detected value of the water temperature is lower than the set value, the heat generation via the power switch 36. While energizing the wires 12 and 13, while the detected value of the water temperature is higher than the set value, the water W in the water tank M is set by stopping the energization to the heating wires 12 and 13 via the power switch 36. Controlled to reach temperature.

  Further, the nighttime set water temperature change control unit 52 includes a light / dark detection unit 38 including a light sensor, a light / dark setting unit 54, a detection output from the light / dark detection unit 38 including the light sensor, and an output from the light / dark setting unit 54. And a water temperature setting change signal generation unit 56. The brightness / darkness setting section 54 stores a brightness setting value (a reference value of ambient brightness for recognizing that it is nighttime) for determining whether it is nighttime.

  The second comparator 55 compares the brightness detection value by the light / dark detection unit 38 with the set value (reference value) of the light / dark setting unit 54, and when the brightness detection value is smaller than the set value. It is determined that it is nighttime, and the comparison output is sent to the water temperature setting change signal generation unit 56, which generates a water temperature setting change signal and sends it to the water temperature setting unit 35. Therefore, the water temperature setting unit 35 is configured to receive a water temperature setting change signal and set the set temperature by lowering it by a certain value (for example, 2 ° C.).

  On the other hand, the second comparator 55 compares the detected brightness value by the brightness detection unit 38 with the set value (reference value) of the brightness setting unit 54, and the detected brightness value becomes the set value (reference value). When the value is larger than (value), it is determined that it is daytime, and the comparison output is sent to the water temperature setting change signal generator 56. The water temperature setting change signal generator 56 generates a water temperature setting change signal. It is sent to the water temperature setting unit 35. Thus, the water temperature setting unit 35 is configured to receive a water temperature setting change signal and raise the set temperature by a certain value (for example, 2 ° C.) to return it to the original value.

  The optical sensor 38 is also referred to as a light / dark sensor or a brightness sensor. Examples of the optical sensor 38 include a photodiode, a phototransistor, and a photo IC.

  The submersible heater is installed in a horizontal position (horizontal arrangement), for example, so that all or substantially the entire heater tube main body 11 is immersed in water in a water tank or the like when used (see FIG. 1).

  Thus, by connecting the plug 220 at the tip of the power cord 21 to the commercial power source, the power from the commercial power source is supplied to the power cord 21, the thermostat unit 2, the heater unit side cord 210, the first heating wire 12, and the thermal fuse 14. , And supplied to the energization circuit around the second heating wire 13. Thereby, the 1st exothermic line 12 and the 2nd exothermic line 13 generate heat, the heat is emitted from the heater pipe main part 11 into water, water is warmed, and the water temperature rises.

  The water temperature is detected by the water temperature sensor 26. The detected value of the water temperature is compared with the temperature set value of the water temperature setter 35 of the set water temperature holding control unit 51 in the thermostat unit 2 to control the energization of the heating wires 12 and 13. Thereby, the water temperature in the water tank M is kept constant.

  The heat of the first heating wire 12 and the second heating wire 13 is transmitted to the thermal fuse 14 through the air in the thermal fuse housing space 15. When a situation occurs in which the temperature of the underwater heater rises abnormally, for example, when the underwater heater is released to the outside of the water tank due to a disaster such as an earthquake or other causes, the internal temperature of the heater tube main body 11 is increased. The temperature fuse 14 suddenly increases and the temperature of the temperature fuse 14 rises abnormally. As a result, the temperature fuse 14 reaches the melting temperature and melts. Thereby, electricity supply to the 1st exothermic line 12 and the 2nd exothermic line 13 is interrupted, and safety is secured.

  Further, when the detection value by the light / dark detection unit (light sensor) 38 becomes smaller than the brightness setting value (reference value) by the light / dark setting unit 54 at night, the second comparator 55 determines that it is night light. Then, the set temperature in the water temperature setting unit 35 is lowered by a certain value (for example, 2 ° C.) by the temperature setting change signal from the water temperature setting change signal generation unit 56. For this reason, the temperature of the water W in the water tank M is controlled (maintained) to a temperature lower than the daytime by a constant value (for example, 2 ° C.) by the function of the set water temperature retention control unit 51.

  Thus, according to the underwater heater, the water temperature at night can be controlled to a temperature lower than the water temperature during the day, so that power consumption can be suppressed and energy saving can be achieved. It can have a positive effect on the life rhythms of other organisms (fish, aquatic plants, etc.). For example, the closer the rhythm of the living body is, the more natural the color of fish and aquatic plants, and the aquatic plants can store more nutrients obtained by daytime photosynthesis by lowering the temperature at night. .

  Further, the night water temperature can be lowered only by using the optical sensor 38 capable of discriminating the night, and the structure can be simplified as compared with the configuration using the conventional timer.

  Furthermore, since it is sufficient to leave the time zone in which the water temperature needs to be lowered to the detection function of the optical sensor 38, a configuration using a conventional timer that requires the addition of a function for setting the time zone in which the water temperature needs to be lowered is provided. Compared with this, it can be manufactured at a significantly lower cost. Therefore, the function of lowering the water temperature at night can be sufficiently applied to general general-purpose machines.

  In addition, since the night time is determined by the light sensor 38, there is an effort to change the setting of the start time and the end time for lowering the nighttime water temperature for each season when the sunset / sunrise time changes as in the case of using a conventional timer. It is not necessary and easy to use.

  The configuration of the thermostat unit 2 is not particularly limited to that of the above-described embodiment, and any design change is allowed as long as it does not depart from the spirit of the claims. is there.

It is the schematic which shows an example of the use condition of the underwater heater which concerns on one Embodiment of this invention. It is sectional drawing which shows the heater part of the underwater heater of FIG. FIG. 2 is a plan view showing a thermostat portion of the underwater heater of FIG. 1 with a part cut away. It is a side view which notches and shows the thermostat part partially. It is a block diagram which shows the electric constitution of the thermostat part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Heater part 2 ... Thermostat part 12 ... Exothermic line 13 ... Exothermic line 38 ... Optical sensor (brightness detection part)

Claims (2)

A heater section having a heating wire;
When the water temperature is lower than a set value, power is supplied to the heating line, and when the water temperature is higher than a set value, a thermostat unit that performs water temperature control by stopping power supply to the heating line;
An optical sensor for detecting ambient brightness,
Based on the fact that the brightness detection value by the light sensor is smaller than the set value, the water temperature set value in the thermostat is lowered, and the brightness detection value by the light sensor is larger than the set value. Based on the above, the submersible heater is configured to increase the water temperature set value in the thermostat and return it to the original value.   The underwater heater according to claim 1, wherein the thermostat unit is configured separately from the heater unit, and the optical sensor is provided in the thermostat unit.

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