JPH0965797A - Heater device for water tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an heater device for a water tank capable of normally controlling the water temperature in a state of a water level sensor outputting a water level sensing signal. SOLUTION: This heater device is obtained by reducing the height of a temperature sensor from that of a water level sensor, forming a sensor unit 2, reducing the height of a heater body 41 forming the heater 4 from the height of the sensor unit 2, installing the heater in a clamp 1 attached to a water tank T and arranging the sensor unit 2 and the heater 4 in the water tank T in the heater device for the water tank equipped with a controlling unit 6 capable of controlling the heater based on a water level output of the water level sensor sensing the water level in the water tank and a temperature output of the temperature sensor sensing the temperature of water in the water tank, maintaining the temperature of the water in the water tank within a prescribed range and cutting off the electric conduction to the heater when the water level unsensing signal from the water level sensor is fed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heater device for maintaining the temperature of water in an aquarium for watching ornamental fish or the like at an appropriate temperature for the ornamental fish or the like.

[0002]

2. Description of the Related Art A conventional heater device for an aquarium described above is
A water level sensor that detects the water level in the aquarium, a temperature sensor that detects the temperature of the water in the aquarium, a heater that warms the water in the aquarium, and the heaters are controlled based on the output of each sensor to control the water in the aquarium. The control unit keeps the temperature within a predetermined range and shuts off the power supply to the heater when a water level non-detection signal is supplied from the water level sensor.

[0003]

In the conventional heater device for the water tank, the water level sensor, the temperature sensor, and the heater are separate. Therefore, the water level sensor, the temperature sensor, and the heater should be arranged at appropriate positions in the water tank. You can However, for example, if the water level sensor and the temperature sensor are located lower than the heater, the water level will drop due to evaporation etc., and if the heater is completely exposed from the water, the water cannot be warmed even if the heater is energized. Since the heater continues to be energized, the temperature of the heater is high and it is dangerous.

If the position of the water level sensor is lower than that of the temperature sensor, the water level drops between the temperature sensor and the water level sensor due to evaporation or the like, and when the temperature sensor is completely exposed from the water surface, Since the temperature of air is detected instead of water, there is a disadvantage that the water temperature cannot be normally controlled.

The present invention has been made to solve the above-described inconvenience, and is for a water tank which can normally control the water temperature when the water level sensor is immersed in water and outputs a water level detection signal. The heater device is provided.

[0006]

According to the present invention, a heater is controlled based on a water level output of a water level sensor detecting the water level in a water tank and a temperature output of a temperature sensor detecting the temperature of water in the water tank. While maintaining the temperature of the water in the water tank within a predetermined range, when the water level non-detection signal is supplied from the water level sensor, in the heater device for the water tank configured with a control unit that shuts off the power supply to the heater, Configure the sensor unit by setting the height of the sensor below the height of the water level sensor,
In the water tank, the height of the heater body forming the heater is lower than the height of the sensor unit. Then, the sensor unit and the heater are attached to the fixture attached to the water tank, the sensor unit is attached to the heater cord with a fixture, and the electrode of the water level sensor is made of conductive rubber, and is attached to the sensor case of the sensor unit. It may be water-repellent, or the electrodes of the water level sensor may be made of a stainless plate.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic view showing an embodiment of a heater device for an aquarium of the present invention. In FIG. 1, T
Indicates a water tank for watching ornamental fish, and W indicates water contained in the water tank T. Reference numeral 1 denotes a clamp as an attachment, which is detachably attached to the frame of the water tank T and has a cord 21 of a sensor unit 2 and a cord 4 of a heater 4 which will be described later.
Positioning is performed by sandwiching 2.

Reference numeral 2 denotes a sensor unit in which a water level sensor and a water temperature sensor are integrated. Reference numeral 3 denotes a kiss rubber, which holds the portion of the sensor unit 2 inserted in the annular portion 31 by its own elasticity, and fixes the sensor unit 2 to the inner surface of the side wall of the water tank T by the suction portion 32 so as not to rotate. Reference numeral 4 denotes a heater for warming the water W in the water tank T. A plug 43 is connected to the tip of a cord 42 extending from the heater body 41 to the outside of the water tank T, and the heater body 41 is arranged lower than the sensor unit 2. There is.

Reference numeral 5 denotes a power plug for supplying electric power to a control unit 6 described later. Reference numeral 6 indicates a control unit connected to the power plug 5, and a heater energization indicator light 63, an alarm indicator light 66, and a water temperature setting dial 6 are provided on the front surface.
7 is provided, the sensor unit 2 is connected via the cord 21, and the heater outlet 7 to which the plug 43 of the heater 4 is connected is also connected.

FIG. 2 is a sectional view showing the sensor unit in the embodiment shown in FIG. In FIG. 2, 21
Is a multi-core cord in which four shielded single-core wires 21a to 21d are inserted, and 22 is four single-core wires 21a to 21d
Shows a printed circuit board to which is connected, and this printed circuit board 2
2 is made of conductive rubber and is pressed against a gold-plated portion provided on one end surface of the printed circuit board 22 so as to have a single core wire 21a.
A second water level detection electrode 23A electrically connected to the second water level which is made of conductive rubber and is pressed against a gold-plated portion provided on the other end surface of the printed circuit board 22 and electrically connected to the single core wire 21b. The detection electrode 23B and the single core wire 21 at one end
A thermistor 24 is provided which is connected to c and whose other end is connected to the single core wire 21d.

Reference numeral 25 denotes a cylindrical sensor case, which is made of a water-repellent resin or has a water-repellent coating applied on the surface thereof. The first and second water level detection electrodes 23A,
A peripheral wall is provided around the openings 25a and 25b exposing a part of 23B, and a projecting strip 25c is provided around the upper ends of the peripheral walls of the openings 25a and 25b with a predetermined interval. Reference numerals 26A and 26B denote rubber caps that close the open end of the sensor case 25, and the rubber cap 26A is provided with an opening 26a through which the cord 21 is inserted.

Reference numeral 27 denotes silicon as a sealing material filled in the sensor case 25, which is for preventing water from entering the sensor case 25. It should be noted that the sensor unit 2 shown in FIG.
Further, the second water level detection electrodes 23A and 23B and the thermistor 24 as a water temperature sensor have the same height.

FIG. 3 is a sectional view showing another example of the sensor unit used in the embodiment shown in FIG. 1. The same or corresponding parts as in FIG.
In FIG. 3, reference numeral 28A denotes a first water level detection electrode obtained by pressing a stainless plate, one end of which is directly connected to the single core wire 21a and the other end of which is exposed at the outer periphery of the sensor case 25 through the opening 25a. Reference numeral 28B denotes a second water level detection electrode obtained by pressing a stainless plate, one end of which is directly connected to the single core wire 21b and the other end of which has an opening 25b on the outer periphery of the case sensor 25.
Exposed from.

Reference numeral 29 denotes a bottomed cylindrical glass tube that closes one open end of the sensor case 25, and the open end opens outward so that it cannot be pulled out from the sensor case 25 at this portion. In the sensor unit 2 shown in FIG. 3, the thermistor 24 is lower than the first and second water level detection electrodes 28A and 28B which form the water level sensor.

FIG. 4 is a block diagram showing an example of the control unit in the embodiment shown in FIG. 1, and FIGS.
The same reference numerals are given to the same portions as. In FIG.
Reference numeral 61 denotes a power supply circuit connected to the power supply plug 5, which supplies drive power to each part and uses an insulating transformer. Reference numeral 62 is a triac as a switch for controlling the supply of electric power from the power plug 5 to the heater outlet 7, and 63 is a heater energization indicator lamp for indicating that electric power is being supplied to the heater outlet 7. The heater energization indicator lamp 63 is connected in series and in parallel between the power plug 5 and the heater outlet 7.

Reference numeral 64 denotes an AC oscillator, which is connected to the first water level detecting electrode 23A or the first water level detecting electrode 28A. Reference numeral 65 denotes a water level determination circuit connected to the second water level detection electrode 23B or the second water level detection electrode 28B.
Water level detection electrode 23A (28A) and second water level detection electrode 23
Whether or not an alternating current is flowing by converting the alternating current detected by detecting the water W between B (28B) as the impedance of the capacitive component into a voltage and comparing it with the reference voltage,
That is, the first and second water level detection electrodes 23A (28
A) and 23B (28B) are determined to be immersed in the water W or completely exposed from the water surface, and a water level detection signal or a water level non-detection signal is output.

Reference numeral 66 denotes a warning indicator light, which includes first and second warning lights.
When the water level determination circuit 65 outputs a water level detection signal in which the water level detection electrodes 23A (28A) and 23B (28B) are immersed in the water W, the light is turned off and the first and / or second water level detection electrodes 23A (28A) and 23B. When the water level determination circuit 65 outputs a water level non-detection signal that (28B) is completely exposed from the water surface, the light is turned off. 67 is a water temperature setting dial, 68 is a water temperature comparison circuit, and this water temperature comparison circuit 68
Compares the set DC voltage corresponding to the water temperature set by the water temperature setting dial 67 with the detected DC voltage corresponding to the water temperature detected by the thermistor 24, and sets the detected DC voltage to a water temperature higher than the set DC voltage, for example, Celsius. The energization signal is output from the state where the voltage difference is once lower to the state where the voltage difference disappears, and the non-energization signal is output when the voltage difference between the detected DC voltage and the set DC voltage disappears.

Reference numeral 69 denotes a heater output control circuit composed of a photocoupler. When a water level detection signal is supplied from the water level determination circuit 65, a signal from the water temperature comparison circuit 68 is output to the gate of the triac 62 to output the water level determination circuit 65. When the water level non-detection signal is supplied from the, the signal from the water temperature comparison circuit 68 is not output to the gate of the triac 62. Therefore, when the water level determination circuit 65 outputs a water level detection signal while the water temperature comparison circuit 68 is outputting an energization signal, the heater output control circuit 69 outputs an energization signal. Electric power is supplied from the plug 5 to the heater outlet 7, but in other states, the heater output control circuit 69 outputs a non-conduction signal, so that the triac 62 becomes non-conductive, and the power plug 5 causes the heater outlet 7 to pass. Power will not be supplied to.

Next, the operation will be described. First, the first and second water level detection electrodes 23A (2
A case where 8A) and 23B (28B) are submerged or submerged in water W will be described. When the first and second water level detection electrodes 23A (28A) and 23B (28B) are immersed in the water W, the water level determination circuit 65 outputs a water level detection signal, so the warning indicator lamp 66 is turned off. , Display that the water level is normal.

In this case, when the detected DC voltage detected by the thermistor 24 is higher than the set DC voltage set by the water temperature setting dial 67, the water temperature comparison circuit 68 outputs an energization signal and the water level determination circuit 65 outputs the water level detection signal. Since it is outputting, the heater output control circuit 69 outputs an energization signal to the gate of the triac 62. Therefore, the triac 62 becomes conductive, and the electric power is supplied from the power source plug 5 to the heater 4 through the heater outlet 7. Therefore, the water W is warmed by the heater 4. When power is supplied to the heater 4 through the heater outlet 7 in this manner, the heater energization indicator lamp 3 is turned on to indicate that the heater 4 is heating the water W.

Then, the water W is heated and the thermistor 24
When the detected DC voltage detected in step 6 becomes the same as the set DC voltage set by the water temperature setting dial 67, the water level determination circuit 65 outputs a water level detection signal, but the water temperature comparison circuit 68 outputs a non-conduction signal. The heater output control circuit 69 is
A non-conduction signal is output to the gate of the triac 62. Therefore, the triac 62 is in a non-conducting state and electric power is not supplied from the power plug 5 to the heater outlet 7, so that the heater 4 cannot warm the water W. When electric power is no longer supplied to the heater outlet 7, the heater energization indicator lamp 3 is turned off and the heater 4 indicates that the water W is not warmed.

When the temperature of the water W drops and becomes higher than the set temperature set by the water temperature setting dial 67, for example, by 1 degree Celsius, the above-described operation is repeated to control the temperature of the water W to an appropriate temperature for the ornamental fish. be able to.

Next, the first and second water level detecting electrodes 23A
When the first and / or second water level detection electrodes 23A (28A), 23B (28B) are completely exposed from the water surface by evaporation or the like from the state where (28A), 23B (28B) is submerged or immersed in water W, Since the water level determination circuit 65 outputs the water level non-detection signal, the warning indicator lamp 66 is turned on to indicate that the water level is abnormal. At this time, since the water level determination circuit 65 supplies the water level non-detection signal to the heater output control circuit 69, the heater output control circuit 69 outputs the non-conduction signal to the gate of the triac 62 regardless of the output of the water temperature comparison circuit 68 to the heater 4. To stop the power supply.

As described above, according to the embodiment of the present invention, the height of the thermistor 24 is set to be equal to or lower than the height of the first and second water level detection electrodes 23A (28A), 23B (28B). And the height of the heater body 41 is made lower than that of the sensor unit 2 and the heater body 41 is arranged in the water tank T. Therefore, the first and second water level detection electrodes 23A (2
If 8A) and 23B (28B) are submerged or submerged in water W, the water temperature can be controlled normally.

When the water level is lowered due to evaporation or the like, the first and / or second water level detection electrodes 23A (28A), 23B (28) must be formed before the heater body 41 is exposed.
Since B) is completely exposed from the surface of the water, the supply of electric power to the heater 4 is cut off, and the heater body 41 can be prevented from reaching a high temperature in an empty state. Further, since the sensor unit 2 and the heater 4 are separate bodies, other ones can be used for each breakage, and the cost can be reduced by using the general-purpose heater 4. .

Since the cord 21 of the sensor unit 2 and the cord 42 of the heater 4 can be positioned by the clamp 1, the sensor unit 2 and the heater body 41 can be easily positioned. Next, as shown in FIG. 4, the shield wires of the single-core wires 21a to 21d of the cord 21 are used for connecting the ground potential of the thermistor 24, so that the temperature control is stable and the noise resistance can be improved. Further, since the thermistor 24 is of a system that detects a DC voltage, it is effective for crosstalk from the water level detection current to the thermistor 24.

Then, the first and second water level detection electrodes 23
Since A and 23B are made of conductive rubber, the first and second water level detection electrodes 28A and
Since 28B is configured, mass productivity is excellent and cost can be reduced. Furthermore, since the sensor case 25 is made water-repellent, it is possible to prevent the deterioration of the water level detection ability due to the capillary phenomenon and the surface tension of the water W, and to ensure the operation of the water level sensor.

FIG. 5 is an explanatory view showing another arrangement example of the sensor unit and the heater. The same parts as those in FIGS. In FIG. 5, reference numeral 1A denotes a clip as a fixture, and the holding portion 1 for holding the annular portion 11 into which the sensor unit 2 is inserted and the cord 42.
2 and 1 are integrally molded.

As shown in FIG. 5, since the sensor unit 2 is fixed to the cord 42 with the clip 1A, the sensor unit 2 and the heater main body 41 can be easily positioned, and the cord 42 is arranged so as not to loosen. As a result, the sensor unit 2 and the heater main body 41 can be easily arranged at desired positions in the water tank T. The annular portion 11 may be configured to hold the sensor unit 2 similarly to the holding portion 12.

In one embodiment described above, the clamp 1
However, other components may be used as long as the sensor unit 2 and the heater 4 can be similarly positioned, attached and fixed. Although the clip 1A is exemplified as the fixture, any other component may be used as long as the sensor unit 2 can be similarly fixed to the cord 42 of the heater 4. Further, the stainless plate is pressed to form the first and second water level detection electrodes 2
Although 8A and 28B are configured, it is possible to use a stainless wire, and thus it is possible to obtain an effect that mass productivity is excellent and cost can be reduced.

Further, as shown in FIG. 2, the first and second
When the water level detection electrodes 23A and 23B and the thermistor 24 are set to the same height, even if the kiss rubber 3 comes off and the sensor case 2 rotates, the first or second water level detection electrodes 23A and 23.
Since B becomes higher than the thermistor 24, the kiss rubber 3 can be omitted, but as shown in FIG.
When 4 is lower than the first and second water level detecting electrodes 28A and 28B, when the kiss rubber 3 comes off and the sensor case 2 rotates, the first and second water level detecting electrodes 28A and 28B become lower than the thermistor 24. It is better not to omit 3.

[0032]

As described above, according to the present invention, the height of the water temperature sensor is set equal to or lower than the height of the water level sensor to form the sensor unit, and the height of the heater main body constituting the heater is set to the height of the sensor unit. Since the water level sensor is disposed at a lower temperature than that of the water level sensor, if the water level sensor is submerged or immersed in water, the water temperature can be normally controlled. When the water level drops due to evaporation or the like, the water level sensor is always completely exposed from the water surface before the heater body is exposed, so that the power supply to the heater is cut off and the heater body does not heat up in a dry state. Can be prevented.

Further, since the sensor unit and the heater are separate bodies, other ones can be used for each damage, and the cost can be reduced by using a general-purpose heater. . Next, position and attach the sensor unit and heater to the fixture,
By attaching the attachment to the water tank, the sensor unit and the heater main body can be easily positioned at desired positions in the water tank.

Alternatively, since the sensor unit is fixed to the heater cord by the fixing tool, the sensor unit and the heater main body can be easily positioned, and the cord is arranged so as not to slacken the sensor unit and the heater main body. Can be easily arranged at a desired position in the water tank. Since the electrodes of the water level sensor are made of conductive rubber and the electrodes of the water level sensor are made of stainless steel, the mass productivity is excellent and the cost can be reduced. Further, since the sensor case is made water-repellent, it is possible to prevent the deterioration of the water level detection ability due to the capillary phenomenon and the surface tension of water, and it is possible to ensure the operation of the water level sensor.

[Brief description of drawings]

FIG. 1 is a schematic view showing an embodiment of a heater device for an aquarium of the present invention.

FIG. 2 is a sectional view showing a sensor unit according to the embodiment shown in FIG.

FIG. 3 is a cross-sectional view showing another example of the sensor unit used in the embodiment shown in FIG.

FIG. 4 is a block diagram showing an example of a control unit in the embodiment shown in FIG.

FIG. 5 is an explanatory diagram showing another arrangement example of a sensor unit and a heater.

[Explanation of symbols]

 T water tank W water 1 clamp 1A clip 11 annular part 12 clamping part 2 sensor unit 23A first water level detection electrode 23B second water level detection electrode 24 thermistor 25 sensor case 27 silicon 28A first water level detection electrode 28B second water level detection electrode 29 glass Tube 3 Kiss rubber 4 Heater 41 Heater body 42 Code 5 Power plug 6 Control unit 62 Triac 65 Water level judgment circuit 67 Water temperature setting dial 68 Water temperature comparison circuit 69 Heater output control circuit 7 Heater outlet

Claims (5)

[Claims] 1. A heater is controlled to control the temperature of water in the water tank based on the water level output of a water level sensor that detects the water level in the water tank and the temperature output of a temperature sensor that detects the temperature of the water in the water tank. While maintaining in a predetermined range, when a water level non-detection signal is supplied from the water level sensor, in a heater device for a water tank configured with a control unit that shuts off energization to the heater, the height of the temperature sensor The height of the heater is less than or equal to the height of the water level sensor, and the height of the heater body that constitutes the heater is lower than the height of the sensor unit in the water tank. Heater device for water tank. 2. The heater device for the aquarium according to claim 1, wherein the sensor unit and the heater are attached to a fixture attached to the aquarium. 3. The aquarium heater device according to claim 1, wherein the sensor unit is attached to a cord of the heater with a fixture. 4. The heater device for a water tank according to claim 1, wherein the electrodes of the water level sensor are made of conductive rubber and the sensor case of the sensor unit is water-repellent. A heater device for an aquarium, which is characterized by having. 5. The heater device for a water tank according to claim 4, wherein the electrode of the water level sensor is formed of a stainless plate.