JP2008142055A - Underwater heater - Google Patents

Abstract

An underwater heater capable of controlling the water temperature with high accuracy and having a high degree of freedom in installation posture in water.
An underwater heater according to the present invention has a tubular heater tube 10 whose both ends in the lengthwise direction are closed, heating wires 12 and 13 housed in the heater tube 10, and water temperature detection. And a water temperature sensor 24. A hollow protrusion 23 projects from the end of the heater tube 10 in the length direction toward the outside in the length direction. A water temperature sensor 24 is accommodated.
[Selection] Figure 1

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, and 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).
JP-A-10-98980

  By the way, this kind of underwater heater is provided with a water temperature sensor in order to detect the temperature of the water in the water tank. Conventionally, since this water temperature sensor is housed in the cylindrical heater tube, the water temperature sensor is lower than the actual water temperature due to the effect of the temperature of the air in the heater tube rising as the heating wire generates heat. There is a tendency to detect high temperatures. That is, the actual water temperature must be judged by discounting the influence of the temperature rise in the pipe due to the heat generated by the heating wire from the temperature detected by the water temperature sensor, and it is difficult to control the water temperature with high accuracy.

  In particular, when an underwater heater is installed in a vertical position in a water tank and used, the air in the heater tube is heated and raised by the heat generated by the heating wire, so the water temperature sensor is arranged at the upper position of the heater tube. Then, it will be greatly affected by the warm air, and a higher temperature will be detected. Therefore, in the past, when installing an underwater heater, it was unavoidable to install it in a horizontal position (a horizontal installation), avoiding a vertical installation. There was also a problem that it was small and unusable.

  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 controlling the water temperature with high accuracy and having a high degree of freedom in installation posture in water.

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

[1] A cylindrical heater tube in which both ends in the length direction are closed;
A heating wire housed inside the heater tube;
A water temperature sensor for detecting the water temperature,
A submerged heater, wherein a hollow projecting portion projects outwardly from an end of the heater tube in the length direction, and the water temperature sensor is accommodated in an internal space of the hollow projecting portion.

[2] A cylindrical heater tube in which both end openings in the length direction of the cylindrical heater tube main body are respectively closed by cap members;
A heating wire housed inside the heater tube;
A water temperature sensor for detecting the water temperature,
A hollow projecting portion projects from the end face of the cap member on one end side of the heater tube toward the outside in the length direction of the heater tube, and the water temperature sensor is accommodated in the internal space of the hollow projecting portion. An underwater heater characterized by that.

  In the invention of [1], since the hollow projecting portion protrudes outward from the lengthwise end of the heater tube, and the water temperature sensor is accommodated in the internal space of the hollow projecting portion, the water temperature sensor The temperature detection by is not easily affected by the temperature rise inside the heater tube due to the heat generation of the heating wire, and the water temperature can be detected with high accuracy, so that the water temperature can be controlled with high accuracy.

  In addition, the temperature detection by the water temperature sensor is not easily affected by the temperature rise inside the heater tube, so the water temperature can be detected with high accuracy regardless of the posture, such as horizontal or vertical (upward or downward) in water. Can do. That is, an underwater heater having a high degree of freedom in installation posture in water is provided.

  In the invention of [2], a hollow projecting portion projects from the end face of the cap member on one end side of the heater tube toward the outside in the length direction of the heater tube, and a water temperature sensor is provided in the internal space of the hollow projecting portion. Therefore, the temperature detection by the water temperature sensor is not easily affected by the temperature rise inside the heater tube due to the heat generated by the heating wire, and the water temperature can be detected with high accuracy. Control becomes possible.

  In addition, the temperature detection by the water temperature sensor is not easily affected by the temperature rise inside the heater tube, so the water temperature can be detected with high accuracy regardless of the posture, such as horizontal or vertical (upward or downward) in water. Can do. That is, an underwater heater having a high degree of freedom in installation posture in water is provided.

  Furthermore, the heater pipe is composed of a heater pipe body whose both end openings are closed with a cap member, and a structure in which a hollow projecting portion protrudes from the end face of one cap member is adopted. Is easier to manufacture.

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

  FIG. 1 is a cross-sectional view showing an underwater heater according to an embodiment of the present invention.

  In this submerged heater, for convenience of explanation, the side where the power cord is drawn is referred to as the base end, and the counter electrode side is referred to as the front end.

  In FIG. 1, 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.

  A first heating wire 12 is arranged in a longitudinal direction on one side of the heating wire support member 16, and the base end of the first heating wire 12 is connected to a power cord 21 through one connection terminal 20a. Is electrically connected to one lead portion 21a.

  Further, the second heating wire 13 is arranged on the other one surface side of the heating wire support member 16 in a longitudinal direction, and the base end of the second heating wire 13 is connected to the power source via the other connection terminal 20b. The other lead portion 21 b of the cord 21 is electrically connected.

  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 power cord 21 side) of the heating wire support member 16 is cut out so as to be substantially U-shaped, and one lead portion of the power cord 21 is cut into the U-shaped notch (not shown). By inserting 21a, the power cord 21 is positioned. 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 protrude from the center of the end surface of the cap member 19 on the base end side, and the power cord 21 is inserted into a hole 22 a 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.

  As shown in FIGS. 2 and 3, a small chamber 23 for accommodating a water temperature sensor is provided on the end surface of the one cap member 19 so as to be adjacent to the power cord lead-out portion 22 and communicate with the inside of the heater tube main body 11. ing.

  The small chamber 23 is formed integrally with the end face of the cap member 19 and is formed of a cylindrical hollow protrusion having a closed end that protrudes outward in the longitudinal direction from the end face. A bar-shaped water temperature sensor 24 is accommodated in the space 23a.

  In addition, each lead wire 24a, 24b of the both ends of the said water temperature sensor 24 is derived | led-out outside using the hole 22a of the said power cord drawer | drawing-out part 22 (refer FIG. 2).

  The outer diameter of the hollow protrusion 23 is smaller than the outer diameter of the heater tube body 11. In the present embodiment, the outer diameter of the hollow projecting portion 23 is designed to be smaller than the outer diameter of the cord lead-out portion 22.

  Next, an example of the procedure for assembling the underwater heater 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.

  Prior to mounting the cap member 19, the water temperature sensor 24 is accommodated in the hollow portion 23 a of the hollow protrusion 23 formed in the cap member 19, as shown in FIGS. The lead wires 24a and 24b are passed through the hole 22a of the power cord lead-out portion 22 and drawn out to the outside.

  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 code 21. Further, the end opening of the heater tube body 11 is also sealed with the 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.

  The underwater heater according to the embodiment is arranged in a horizontal posture (horizontal arrangement), a vertical posture, or the like so that all or substantially all of the heater tube main body 11 is immersed in water in a water tank or the like. Installed.

  Thus, by connecting a plug (not shown) at the tip of the power cord 21 to the commercial power source, the power from the commercial power source is connected to the power cord 21, the first heating wire 12, the thermal fuse 14, and the second heating wire 13. Supplied to the closed circuit. 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 the water, water is warmed, and the water temperature rises.

  Although the water temperature is detected by the water temperature sensor 24, when the temperature exceeds the set temperature, the energization is stopped, so that the water temperature is controlled to be maintained at the set value.

  At this time, since the water temperature sensor 23 is accommodated in the hollow portion 23a of the hollow projecting portion (small chamber) 23 provided on the end surface of the cap member 19 in a state of communicating with the inside of the heater tube main body 11, the water temperature sensor 23 The temperature detection by is less likely to be affected by the temperature rise of the air inside the heater tube main body 11 accompanying the heat generation of the first heating wire 12 and the second heating wire 13. That is, the temperature in the water can be detected almost without being affected by the temperature inside the heater tube main body 11, and thus the water temperature can be controlled with high accuracy.

  Further, since the temperature detection of the water temperature sensor 24 is hardly affected by the temperature rise of the air inside the heater tube main body 11, there is no problem even if it is installed in the vertical posture, not limited to the usage mode in which it is installed in the horizontal posture in the water. Can be used. In other words, the water temperature can be detected with high accuracy even when the water is placed in any posture such as a horizontal posture (horizontal placement), a vertical posture (upward / downward), and an oblique posture.

  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.

  In the present invention, the inner diameter of the hollow protrusion 23 is preferably set to a size that can accommodate the rod-shaped water temperature sensor 24. That is, the inner diameter of the hollow protrusion 23 is preferably larger than the outer diameter of the rod-shaped water temperature sensor 24 and not more than three times the outer diameter. In this case, the heater accompanying the heat generation of the heating wires 12 and 13 Since the influence of the temperature rise inside the pipe 10 can be made less susceptible, the water temperature can be detected with higher accuracy. Among these, it is particularly preferable that the inner diameter of the hollow protruding portion 23 is larger than the outer diameter of the rod-shaped water temperature sensor 24 and not more than twice the outer diameter. By adopting such a configuration, the water temperature can be further increased. It becomes possible to detect with accuracy.

  In addition, in the said embodiment, although the hollow protrusion part 23 is formed in the cylindrical shape, it is not specifically limited to such a shape. In the said embodiment, although the hollow protrusion part 23 is formed in the cylindrical shape corresponding to the rod-shaped water temperature sensor 24, if the water temperature sensor 24 is a flat elliptic cylinder shape, for example, the shape of the hollow protrusion part 23 will be shown. May be formed in the same flat elliptical cylindrical shape.

  Moreover, in the said embodiment, although the hollow protrusion part (small chamber) 23 is integrally formed in the end surface of the said cap member 19, it is not limited to such a structure in particular. For example, the structure which connected the hollow body of a separate front-end | tip obstruction | occlusion with respect to the hole formed in the end surface of the cap member 19 in a liquid-tight state is also employable.

  Moreover, in the said embodiment, although the hollow protrusion part (small chamber) 23 was provided in the cap member 19 of the base end side, it is not specifically limited to such a structure, The cap member 25 of the front end side is provided. It may be provided. Further, when a heater tube body 11 having a structure in which one end side is closed is used, the hollow projecting portion (small chamber) 23 is provided on a cap member attached and fixed to the other end side of the heater tube body 11. Alternatively, it may be provided on the closed end face of the heater tube main body 11.

  Moreover, in the said embodiment, although a heat generating part is the structure which consists of the 1st heat generating line 12 and the 2nd heat generating line 13, it is not limited to such a structure in particular, A heat generating part consists of one heat generating line. The structure which becomes may be sufficient.

It is sectional drawing which shows the underwater heater which concerns on one Embodiment of this invention. It is an expanded sectional view of the base end side in which the hollow protrusion part (small chamber) in the underwater heater was provided. It is an external appearance perspective view of the cap member provided with the hollow protrusion part (small chamber).

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Heater pipe 11 ... Heater pipe main body 12 ... Heating wire 13 ... Heating wire 19 ... Cap member 23 ... Hollow protrusion part (small chamber)
23a: Hollow part (internal space)
24 ... Water temperature sensor 25 ... Cap member

Claims (2)

A cylindrical heater tube whose both ends in the length direction are closed;
A heating wire housed inside the heater tube;
A water temperature sensor for detecting the water temperature,
A submerged heater, wherein a hollow projecting portion projects outwardly from an end of the heater tube in the length direction, and the water temperature sensor is accommodated in an internal space of the hollow projecting portion. A cylindrical heater tube in which both end openings in the length direction of the cylindrical heater tube main body are respectively closed by cap members;
A heating wire housed inside the heater tube;
A water temperature sensor for detecting the water temperature,
A hollow projecting portion projects from the end face of the cap member on one end side of the heater tube toward the outside in the length direction of the heater tube, and the water temperature sensor is accommodated in the internal space of the hollow projecting portion. An underwater heater characterized by that.

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