JP2579777Y2 - Water pipe freezing prevention device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water pipe freezing prevention device used in a cold region to prevent freezing of water in a water pipe.

[0002]

2. Description of the Related Art A water pipe freezing prevention device disclosed in Japanese Utility Model Laid-Open Publication No. Sho 62-184686 is conventionally known. In the above water pipe freezing prevention device, a PTC having a positive temperature coefficient thermistor is provided.
The heater is fixed to a heat sink, and the heat sink is connected continuously by a plurality of lead wires. The water pipe freeze prevention device is used by attaching the heat sinks to the outer peripheral surface of a water pipe to be attached along the respective heat sinks.

Therefore, in the above heat sink, PT
In order to effectively transfer the heat from the C heater to the water pipe,
A recess having a substantially semicircular cross section is formed so as to be in close contact with the outer peripheral surface of the water pipe.

[0004]

However, in the above-described conventional structure, it is necessary to adjust the concave portions of the heat sink to the curvatures of the outer peripheral surfaces of the individual water pipes. Is difficult to completely match the curvature of the outer surface of the water pipe. If the curvature does not match even slightly, the contact between the heat sink and the water pipe becomes line contact or point contact, and the contact area decreases. Drops, water frozen in the water pipe freezes,
There is a problem that the water pipe may burst.

[0005]

The water pipe freezing prevention device according to claim 1 of the present invention has the following objects.
The fixing means for the heating element having a positive temperature coefficient thermistor is fixed on the outer peripheral surface of the water pipe is provided, stainless Wu
Metal band woven from metal wire into a band, or phosphor blue
A heat transfer means, which is formed of at least one of copper thin plates and transmits heat and is deformed by pressing, is provided so as to be sandwiched between the water pipe and the heating element by the fixing means. And

According to a second aspect of the present invention, there is provided an apparatus for preventing freezing of a water pipe, wherein a heating element for heating the water pipe is provided with a positive temperature coefficient thermistor, and an attaching means made of an elastically deformable shape memory alloy is provided. The heating element is detachably attached to the outer peripheral surface of the water pipe at room temperature, and is formed so as to be deformed in a direction in which the heating element is in close contact with the water pipe when heated, and is attached to the heating element. It is characterized by.

[0007]

According to the structure of the first aspect, the heat from the heating element is formed by knitting a stainless wool or a metal wire in a belt shape.
Metal band or at least one sheet of phosphor bronze
The heat is transmitted to the outer peripheral surface of the water pipe through a heat transfer means, which is formed of a seed and transmits heat, and is deformed by pressing, and heats the water pipe. Freezing can be prevented. At this time, when the heating element reaches a predetermined temperature by the positive temperature coefficient thermistor, the heating element maintains the predetermined temperature, so that the temperature control mechanism can be omitted and the size can be reduced.

In addition, in the above configuration, since the heat transfer means is deformed by pressing, the heat transfer means is provided between the water pipe and the heating element by the fixing means, so that the heat transfer means is provided on the water pipe. The heating element can be fixed to the water pipe by being deformed along the outer peripheral surface.

Thus, the above structure can secure a contact portion between the heat transfer means and the water pipe even when the curvature of the outer peripheral surface of the water pipe changes due to a molding error or the like.

According to the second aspect of the present invention, the mounting means mounted on the heating element is formed detachably with respect to the water pipe at room temperature and elastically deforms.
The heating element can be easily attached to the water pipe, and since the mounting means comes into close contact with the water pipe when heated, heat from the heating element can be transmitted to the water pipe via the metal mounting means. it can.

Therefore, the above configuration can secure a contact portion between the mounting means and the water pipe even if the curvature of the outer peripheral surface of the water pipe changes due to a molding error or the like.

[0012]

[Embodiment 1] One embodiment of the present invention will be described as Embodiment 1 with reference to FIGS. 1 to 8 as follows.

FIGS. 1 and 2 show a water pipe freezing prevention apparatus.
As shown in FIG. 1, a heater unit (heating element) 1 having a PTC thermistor that generates heat when energized is used to heat a water pipe 2. A hose band (fixing means) 3 for fixing the heater unit 1 on the outer peripheral surface of the water pipe 2 extends from the rear side of the heater unit 1 to the outer peripheral surface of the water pipe 2. On the outer surface,
It is provided so that it can be fastened by the screw 3a. Note that the back side of the heater unit 1 refers to the side opposite to the heat generating surface 1a of the heater unit 1.

In the water pipe freezing prevention device, the stainless steel wool (heat transfer means) 4 that transmits heat well and deforms when pressed is sandwiched between the water pipe 2 and the heater unit 1. As described above, the heater unit 1 is provided over the entire surface of the heat generating surface 1a. In addition,
The stainless steel wool 4 may be stuck on the heat generating surface 1a, or may be simply held between the heat generating surface 1a and the water pipe 2 by abutting.

Thus, the heater unit 1
The stainless steel wool 4 is deformed along the outer peripheral surface of the water pipe 2 by being pressed against the water pipe 2 by the hose band 3 so as to closely contact the outer peripheral surface of the water pipe 2. I do. Therefore, when the heater unit 1 is caused to generate heat by energization, the heat from the heater unit 1 is transmitted to the water pipe 2 via the stainless steel wool 4.

By the way, conventionally, a concave portion having a substantially semicircular cross section is formed in a heat sink for transmitting heat to a water pipe so as to extend along the outer peripheral surface of the water pipe. The heat sink and the water pipe may be in point contact or line contact, and the contact area is reduced, so that the heat transfer efficiency is reduced. In addition, when the above-mentioned heat sink is attached to a water pipe of another standard, point contact or line contact similarly occurs, and the heat conduction efficiency is reduced. Such a decrease in the conduction efficiency causes a decrease in the heating efficiency of the water pipe, resulting in poor freezing prevention.

However, in the configuration of the first embodiment,
Even if a molding error occurs in the water pipe 2, the stainless steel wool 4 is deformed according to the molding error of the outer peripheral surface of the water pipe 2. Can be maintained.

With this configuration, the above-described configuration can avoid a decrease in the heat transfer efficiency from the heater unit 1 due to a decrease in the contact area due to a molding error of the water pipe 2 which is likely to occur in the related art. Can prevent freezing of water that has accumulated in the water.

In addition, since the above configuration can increase the range of deformation of the stainless steel wool 4, the water pipes 2 of various standards can be used.
, The tight contact between the outer peripheral surface of each water pipe 2 and the stainless steel wool 4 can be maintained, and a reduction in the efficiency of heat conduction from the heater unit 1 can be avoided while maintaining various standards. It can be applied to each water pipe 2.

Next, the heater unit 1 will be described. As shown in FIGS. 3 and 4, the heater unit 1 includes a heating element 5, metal terminals 6.6, lead wires 7.7 serving as power supply lines, and an insulating case 8 serving as a covering member having electrical insulation. It is composed of

The heating element 5 has a positive temperature coefficient (Positive Tempe
The material has low resistance from room temperature to the Curie temperature Tc (rapid change temperature), but has a low Curie temperature Tc. This is a positive temperature coefficient thermistor as a thermosensitive element having a characteristic in which the resistance value increases sharply when it exceeds.

Due to the above characteristics, when a voltage is applied, the heating element 5 initially has a low resistance and a large current flows due to a low temperature, and as a result, the temperature rises sharply while the temperature rises rapidly. When the temperature exceeds the Curie temperature Tc, the resistance value sharply increases, so that the temperature does not rise above a certain temperature and the temperature is kept stable. That is, the heating element 5 can have a self-temperature control function.

Accordingly, since the heater unit 1 can omit the temperature control circuit and the overheat prevention circuit, it consumes less power and can be downsized. In addition, there is no fear of ignition or the like due to local overheating, and no noise or the like is generated.

The heating element 5 can have a Curie temperature Tc arbitrarily set within a range of about 30 ° C. to 250 ° C. depending on the material composition. The Curie temperature Tc may be set to a temperature at which water in the pipe is prevented from freezing, and in consideration of safety and power saving.

The heating element 5 is an electrode 5 formed by applying, for example, a silver paint on the upper and lower surfaces of a flat disk.
a.5a. On the other hand, the metal terminal 6 is
Each metal terminal 6 is formed with a power supply portion 6 a for connecting a lead wire 7. The power supply portions 6a are substantially parallel to each other, and extend in a direction in which the corresponding lead wires 7 are introduced.

The electrical connection between the heating element 5 and the metal terminals 6, 6 is made by attaching the electrode 5a of the heating element 5 and the metal terminal 6 with, for example, an epoxy resin / silver mixed conductive adhesive. Is being done. In addition, the power supply units 6a and 6a and the lead wires 7
The electrical connection with the power supply 7 is made by, for example, soldering the corresponding lead wires 7 to the opposing surfaces of the power supply units 6a.

The insulating case 8 comprises an insulating case lower part 8a as a covering base and an insulating case upper part 8b. The insulating case 8 includes a heating element 5 and metal terminals 6.
6 is sealed and formed, that is, sealed. The insulating case 8 is provided so that a mechanical load is not applied to a soldered portion between the lead wire 7 and the power supply portion 6a of the metal terminal 6 so that disconnection or the like does not occur.
The side ends are also covered.

The above-mentioned insulating case 8 accommodates the heating element 5 and the like in an insulating case lower part 8a formed in advance by injection molding or the like, and is installed in an injection molding die (not shown). By injecting and molding the plastic to be a part, the insulating case lower part 8a and the insulating case upper part 8b are integrally formed. Thus, the heating element 5 and the like are sealed and fixed inside the insulating case 8.

The insulating case 8 has a small heat shrinkage, is excellent in heat conductivity and mechanical strength, has heat resistance enough to withstand the heat generation temperature of the heating element 5, waterproofness not passing moisture such as water vapor, and air. Having airtightness that does not pass through the inside,
In addition, it is necessary that the lead wires 7 have good adhesion to the coating material, and are formed of, for example, a polymer alloy made of polyamide, polypropylene, and glass fiber.

In the heater unit 1 described above, the lead wires 7.7 are connected to the opposing surfaces of the metal terminals 6.6 on the power supply portions 6a 6a, respectively, so that the outer surfaces of the metal terminals 6.6 are No irregularities occur due to the connection of the lead wires 7.

Therefore, it is not necessary to provide the insulating case 8 with a thickness for absorbing such irregularities, and the insulating case 8, that is, the heater unit 1 can be formed thin. Therefore, the heater unit 1 can be downsized, and the heat generated by the heating element 5 can be efficiently transmitted from the heating surface 1a to the stainless steel wool 4 via the metal terminal 6, as shown in FIG. .

The heater unit 1 may be energized at all times, or may be provided with a switch (not shown) to manually turn on / off.

As described above, in the above configuration, when the heater unit 1 is attached to the water pipe 2, the stainless wool 4 on the heater unit 1 is deformed by being pressed most between the water pipe 4 and the water pipe 4. It passes along the center of the heating element 5 of the unit 1 and along the heater unit 1 parallel to the center axis of the water pipe 2.

[0034] With this arrangement, the portion that has the highest heat transfer efficiency because it is most deformed and compacted by pressing when attached, and the heater unit 1 on the center of the heating element 5 that has the highest temperature come into contact with each other. The conduction efficiency can be improved.

In the structure of the first embodiment, the example using the stainless steel wool 4 has been described. However, the structure is not particularly limited as long as it can transmit heat well and can be deformed by pressing. As shown in FIG. 5 and FIG. 6, a phosphor bronze thin plate 9 having elasticity may be formed in a bellows shape and attached to the heater unit 11. The heater unit 11 has a mounting hole 11a to be described later for mounting the phosphor bronze thin plate 9 to the heater unit 1.

In place of the stainless steel wool 4,
A metal band formed by knitting a metal wire such as stainless steel into a band shape may be formed in a bellows shape or a ring shape, and attached to the heater unit 11.

When such a phosphor bronze thin plate 9 or metal band is pressed against the outer peripheral surface of the water pipe 2, it is deformed along the outer peripheral surface, so that heat from the heater unit 1 is efficiently transferred to the water pipe 2. Can be transmitted to

Further, in order to mount the phosphor bronze thin plate 9 and the metal band on the heater unit 11 as described above, as shown in FIGS. 5 is provided with a mounting hole 11a coaxial with the central axis.

Therefore, in the heater unit 11, an annular heating element 12 is used in place of the heating element 5, and an insulating case 15 and each electrode plate 13 are also formed so as to form the mounting hole 11a. ing. The lead wire 14 in the drawing is the same as the lead wire 7, and the materials of the heating element 12, the electrode plate 13 and the insulating case 15 are the same as those of the heating element 5, the electrode plate 6 and the insulating case 8. The same is true.

Second Embodiment Next, another embodiment of the present invention will be described as a second embodiment with reference to FIGS. 9 and 10. FIG. Note that members having the same functions as those in the first embodiment are given the same member numbers, and descriptions thereof are omitted.

In the water pipe freezing prevention device, as shown in FIG. 9, a gripper (mounting means) 10 for fixing the heater unit 11 on the outer peripheral surface of the water pipe 2 is mounted on the heater unit 11. . The above mounting is performed by fastening the mounting hole 11a of the heater unit 11 and the gripping part 10 through a bolt 16.

The grip 10 has a pair of bow-shaped curved arms 10a so that the shape memory alloy can be elastically deformed and the outer peripheral surface of the water pipe 2 can be gripped from both sides. It is molded. Thus, the grip 10 can be detachably attached to the water pipe 2 by elastic deformation.

Further, as shown in FIG. 10, when the grip 10 is heated to a temperature at which water in the water pipe 2 can be prevented from freezing, each of the arms 10a and 10a of the grip 10 is heated.
are set so as to be displaced in directions approaching each other. Thereby, each of the arm portions 10a, 10a
When heated as described above, the inner surfaces of the two are connected to the water pipe 2
Are adhered to each other along the outer peripheral surface.

Thus, while the structure of the second embodiment can be easily attached to and detached from the water pipe 2 at room temperature, when it is mounted on the water pipe 2 and heated, the grip 10 is attached to the water pipe 2. And each arm 10a, 10a of the grip 10
a and the outer peripheral surface of the water pipe 2 are fixed in close contact with each other.

Therefore, in the above configuration, the heat from the heater unit 11 is transferred to the water pipe 2 through the grip 10.
Is efficiently heated over substantially the entire circumference thereof, so that freezing of water in the water pipe 2 can be prevented.

[0046]

As described above, the water pipe freezing prevention device according to the first aspect of the present invention is provided with the fixing means for fixing the heating element having the positive temperature coefficient thermistor on the outer peripheral surface of the water pipe. Stainless steel wool, metal bar woven from metal wire
Or at least one of phosphor bronze sheets.
The heat transfer means for transmitting heat and deforming by pressing is provided so as to be sandwiched between the water pipe and the heating element by the fixing means.

Therefore, in the above configuration, since the heat transfer means is deformed by pressing, the heat transfer means is attached between the water pipe and the heating element by the fixing means, so that the heat transfer means is connected to the water pipe. The heating element can be fixed to the water pipe by being deformed along the outer peripheral surface of the water pipe.

With this configuration, even if the curvature of the outer peripheral surface of the water pipe changes due to a molding error or the like, a contact portion between the heat transfer means and the water pipe can be secured. This has the effect of avoiding a decrease in the efficiency of heat transfer to the tube.

Further, even if the curvature of the outer peripheral surface of the water pipe changes, the above-mentioned configuration can apply the heat transfer means to the outer peripheral surface, so that it can be applied to water pipes of various standards.
This also has the effect that the applicable range can be expanded.

As described above, in the water pipe freezing prevention device according to the second aspect of the present invention, the heating element for heating the water pipe is provided with the positive temperature coefficient thermistor, and is made of the elastically deformable shape memory alloy. Attachment means is formed so that the heating element can be attached to and detached from the outer peripheral surface of the water pipe at room temperature, and is deformed in a direction in which the heating element is in close contact with the water pipe when heated. The configuration is attached.

Therefore, in the above configuration, the mounting means attached to the heating element is formed so as to be detachable from the water pipe at room temperature and is elastically deformed. In addition, since the attaching means comes into close contact with the water pipe when heated, the heat from the heating element can be transmitted to the water pipe via the attaching means made of metal.

Therefore, in the above configuration, even if the curvature of the outer peripheral surface of the water pipe changes due to a molding error or the like, a contact portion between the mounting means and the water pipe can be secured. Therefore, it is possible to avoid a decrease in the heat conduction efficiency of the device.

Further, the above-mentioned configuration can be applied to water pipes of various standards, because the mounting means can follow the outer circumference even if the curvature of the outer circumference of the water pipe changes.
This also has the effect that the applicable range can be expanded.

[Brief description of the drawings]

FIG. 1 is a plan view of a water pipe freezing prevention apparatus according to a first embodiment of the present invention when the water pipe freezing prevention apparatus is attached to the water pipe;

FIG. 2 is a front view when the water pipe freeze prevention device is attached to a water pipe.

FIG. 3 is a partially broken plan view of a heater unit of the water pipe freeze prevention device.

FIG. 4 is a sectional view of the heater unit.

FIG. 5 is a plan view of a water pipe freezing prevention apparatus showing a modification of the first embodiment.

FIG. 6 is a plan view when the water pipe freezing prevention device is attached to a water pipe.

FIG. 7 is a partially broken plan view of a heater unit of the water pipe freezing prevention device.

FIG. 8 is a sectional view of the heater unit.

FIG. 9 is a plan view at room temperature when the water pipe freezing prevention device according to the second embodiment of the present invention is attached to the water pipe.

FIG. 10 is a plan view of the water pipe freezing prevention device when it is heated.

[Explanation of symbols]

 Reference Signs List 1 heater unit (heating element) 2 water pipe 3 hose band (fixing means) 4 stainless steel wool (heat transfer means)

Claims (2)

(57) [Scope of request for utility model registration] [Claim 1] A fixing means for the heating element is fixed to the outer peripheral surface of the water pipe having a positive temperature coefficient thermistor provided, stearyl
Stainless steel wool, a metal band made of metal wire
Or at least one of a phosphor bronze thin plate , and a heat transfer means for transmitting heat and deforming by pressing is provided so as to be sandwiched between the water pipe and the heating element by the fixing means. A water pipe freezing prevention device characterized in that: 2. A heating element for heating a water pipe is provided with a positive temperature coefficient thermistor, and mounting means made of an elastically deformable shape memory alloy is used to connect said heating element at room temperature to an outer peripheral surface of the water pipe. A water pipe freezing prevention device which is formed so as to be detachable with respect to the water pipe, and is formed so as to be deformed in a direction in which it is brought into close contact with the water pipe when heated, and is attached to the heating element.