JPS6217494A - Piping heat-insulating heater - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a pipe heat-retaining heater for maintaining a constant pipe temperature or preventing freezing in a fluid transfer pipe.

[Conventional technology]

When a fluid, generally a liquid, is transferred through piping, it may be required to maintain the liquid piping at a constant temperature.

On the other hand, in cold regions, when the pipe temperature decreases due to a drop in outside air temperature, and fluid is transferred through the pipe, it is impossible to maintain the pipe temperature constant even if a heat insulating cover is attached to the pipe. Furthermore, if the fluid is tap water, the pipes may burst due to freezing. To prevent this freezing,
BACKGROUND ART Conventionally, a means has been implemented in which a linear or band-shaped heating element is generally spirally wound between the outer periphery of a pipe and a heat insulating cover, and the pipe is heated by the heating element to prevent freezing. This method can also be applied when maintaining the pipe temperature constant.

However, when winding a conventional linear or band-shaped heating element around a pipe in a spiral manner, there is a risk of double winding. Also, if the heating element is not wrapped closely around the pipe, its heating effect will be reduced.1 For example, if the heating element is wrapped around the pipe for 20 meters,
It becomes necessary to wrap it while preventing loosening using vinyl tape or the like.

In such winding, winding may be difficult due to other obstacles, or due to lack of electrical knowledge of the operator, a conductor such as wire may be used to prevent loosening. The double-wound portion and the wire-based loosening prevention portion may become electrically short-circuited, causing abnormal heat generation in those portions and causing a fire.

Thermal covers used to block out cold outside temperatures are generally made of styrofoam material, which is resistant to low temperatures but weak against high temperatures and can cause fires, due to its heat retention effect and economic efficiency. be.

In addition, the conventional heating element described above generates heat due to the electrical resistance of a metal resistor such as a nichrome wire, and generates a predetermined amount of heat depending on a specific length of the nichrome wire. In order to prevent abnormal heat generation, the heating element must be used at a specified winding interval.Due to the length of the piping, even if there is extra length in the heating element, it cannot be cut. On the other hand, if the wire is wrapped too tightly, abnormal heat generation will occur. Furthermore, even if the length of the heating element is insufficient for the piping, it is impossible to add more because the desired heat generation cannot be obtained due to changes in electrical resistance, which is inconvenient in actual construction.

In order to solve the above problems, the applicant (inventor) of the present invention invented a heat-generating heater and filed an application (Application number: Japanese Patent Application No. 80-80).
No. 44755, filed on March 8, 1980), the heat-generating heat-retaining heater has an opening extending over the entire length of a cylindrical shape and is made of a thin sheet material that is electrically insulating and waterproof and has elasticity. an inner cylinder, two parallel conducting wires extending in the longitudinal direction attached to the outer periphery of the inner cylinder, and a flat plate or linear conductor electrically connected in parallel with a space between the two parallel conducting wires; The heat generating part is made of a heating element, and the outer cylinder is made of an electrically insulating and waterproof thin sheet that is attached to the outer periphery of the inner cylinder with the heat generating part tightly attached to the outer periphery of the inner cylinder. This is a heat-retaining heater with a unique feature.

In addition, the applicant (inventor) of the present invention further invented and filed a piping insulation heater (Application number: Japanese Patent Application No. 1983-58117,
The piping insulation heater, filed on March 25, 1985, has an outer cylinder made of an elastic, electrically insulating and waterproof thin sheet material with openings formed over the entire length of the cylinder. , two parallel conducting wires extending in the longitudinal direction attached to the inner part of the nuclear outer cylinder, and one flat heating element electrically coupled between the two parallel conducting wires. and an inner cylinder made of an electrically insulating and waterproof thick sheet adhered to the inner periphery of the outer cylinder with the heat generating part closely attached to the inner periphery of the outer cylinder. This is a piping heat-retaining heater characterized in that two parallel conducting wire connection terminals are fixed at both ends in the longitudinal direction between an outer cylinder and an inner cylinder.

[Problem that the invention seeks to solve]

As mentioned above, the conventional means for keeping pipes warm and preventing water pipes from freezing has a structure in which a linear or band-shaped metal resistance heating element is spirally wrapped around the pipes and a heat-insulating cover. There is a risk of a fire accident, and there is also a restriction that cutting and joining cannot be done depending on the usage conditions, which is inconvenient.

On the other hand, the heat-generating heat-retaining heater proposed by the applicant of the present invention (Japanese Patent Application No. 80-44755) can solve most of the drawbacks of using the conventional linear or band-shaped metal resistance heating element, but it is difficult to manufacture. However, it cannot be said that the problems in use or construction were completely resolved.

In addition, although the piping insulation heater (Japanese Patent Application No. 80-58117) made by the applicant of the present invention was able to solve problems in production, use, and construction to a considerable extent, it was not able to sufficiently insulate the bent portions of the piping. Furthermore, it was necessary to arrange and connect a dedicated conductor at this bent portion.

Furthermore, there were other problems, such as insufficient heat insulation at twisted portions of the piping, and insufficient heat insulation at locations with especially severe cooling conditions or large diameter portions.

The present invention can be used to insulate piping, not only in straight pipe parts but also in bent parts,
In order to further enhance the heat retention effect even in twisted parts, large diameter parts, and areas with severe cooling conditions, it can be installed in a spiral shape on piping, and there is no need for a special heater arrangement, but with one long continuous heater. In addition to being able to keep warm, this heating element has a positive temperature coefficient of resistance, so it has the property of automatically controlling the amount of heat generated by itself according to changes in ambient temperature, so it is possible to use radio waves and a thermostat to control the temperature. It is an object of the present invention to provide a highly safe piping heat-retaining heater that does not generate heat above a set heat generation temperature even if it fails and is continuously energized or a thermostat is not installed.

[Means for solving problems]

The means of the present invention for solving the above problems includes a cylindrical body made of an elastic waterproof and electrically insulating material, in which an opening extending along the entire length in the axial direction is formed, and a tube embedded in the cylindrical body. Two parallel conducting wires extending in the axial direction of the body, a slightly circular flat heating part electrically connected between the two parallel conducting wires, and connecting parts symmetrically centered around the heating part. 2. A piping heat-retaining heater, characterized in that the cylindrical body has a plurality of continuously repeating notches formed in the cylindrical body, and the cylindrical body may have a circular or elliptical cross section, and The width of the cut portion is 10 to 30% of the total circumference of the cylinder, and the length of the notch in the circumferential direction of the cylinder is symmetrical to about 30% of the total circumference of the cylinder. It can be used and removed by cutting at right angles to the direction, and can be used by cutting and removing the cylindrical portion corresponding to the notch at bent or twisted portions of the piping to be installed, and can be further connected in the longitudinal direction. This is a pipe heat-retaining heater that can be used as a pipe heater and is equipped with a pipe temperature sensor, power source, and energization confirmation means.

[Effect]

The piping heater of the present invention can be continuously attached to any of the two straight pipe parts, the bent part, the twisted part, and the large diameter part.

〔Example〕 Next, the present invention will be described by way of examples with reference to the drawings.

FIG. 1 is a perspective view of one embodiment of the present invention, FIG. 2 (A),
(B) is a cross-sectional view and a developed cross-sectional view of FIG. 1, and FIG. 3 is a developed plan view of FIG. 1. In these figures, the pipe insulation heater l of the present invention has an opening 2 extending over the entire length in the axial direction.
A cylindrical body 2 made of an elastic waterproof electric insulating material having a shape of 2.a and 2 parallel conducting wires 3.
3 and a slightly circular flat heating section 4 electrically connected between the parallel conducting wires 3 and 3. The heating section 4 is made of a heating element mixed with carbon powder and a resin such as polyethylene, or a nonwoven fabric made of carbon fiber. Since the non-heating element is a heating element with a positive temperature coefficient of resistance, the heating element itself has the property of automatically controlling the amount of heat generated according to changes in the ambient temperature, so it is used as a thermostat to control the current and temperature. It is a highly safe product that will not generate heat above the set temperature even if it is continuously energized or a thermostat is not installed due to a malfunction. After the parallel conducting wires 3 and the heat generating part 4 are attached to the outer surface of the cylinder 2, the outer surface is covered with a waterproof and electrically insulating covering part 4a. The opening 2a and the heat generating part 4 are located approximately symmetrically with respect to the circumference of the cylinder.The cylinder 2 has a triangular notch 5 symmetrically with respect to the heat generating part 4, leaving a partial connection part 5a. It is formed in a shape that is repeated many times in succession. The convergence W between the two parallel conducting wires 3, 3 is approximately 10 to 30% of the total circumference of the cylinder 2, and the notch 5
The length W2 in the circumferential direction of the cylinder body is generally about 30% symmetrical about the entire circumference of the cylinder body 2. These values are determined empirically, taking into account the heat retention conditions, the shape of the tube, etc. The cylindrical body 2 may be a perfect circle, but it is preferable that the cylindrical body 2 is formed in an elliptical cross section with the short axis being a line connecting the opening 2a and the heat generating part 4, so as to be advantageous for mounting the cylinder 2 on a 5V.

FIG. 4 is a perspective view of an embodiment in which the present invention is applied to heat insulation of piping, and the piping 10 has a straight pipe portion 10a and a bent portion 10b constituted by an elbow. The pipe heat retaining heater l is installed by enlarging the opening 2a of the cylindrical body 2 and holding the pipe 10, but for the straight pipe part 10a, the cylindrical body
The opening 2a is expanded as it is, and the bent part 10b, which is an elbow with a larger diameter than the straight pipe part foa, is held by cutting out a triangular cut part 5a corresponding to the length of the bent part 10b. In this way, as shown in FIG. 4, the piping heater l can be easily and reliably attached to the bent portion 10b. The same holds true when the bent portion 10b has the same diameter or smaller diameter than the straight tube portion 10a, and even if the bent portion 10b is bent in a different direction, it can be held as shown in FIG. 4.

As shown in FIG. 5, even when a twisted portion 10c is formed in the pipe 10, if the notch 5 of the cylinder 2 corresponding to the twisted portion 10c is cut out and held, the insulation heater 1 can be attached to the pipe. It can be easily and reliably attached to IO.

As shown in FIG. 6, when the piping 10 is subjected to severe cooling conditions, the heat insulating heater 1 can be installed in a spiral shape. In this case, the arrangement density of the heat generating portions 4 per length of the pipe increases, and the heat retention effect increases.

When the heat insulating heater l is attached to the piping 10, the heat insulating heater l is generally covered with a heat insulating material (not shown) made of styrene foam or the like.

As shown in FIG. 4, a power supply unit 20 is connected to one part of the piping heater l, and the connection part is covered with an electrically insulating and waterproof cover 30, and the other end part 1a is also covered with a similar cover. 3
Covered with 0. It is also possible to connect another pipe heat-retaining heater 1' indicated by a chain line to the opposite side (upper part in the figure) of the power supply section 20.

FIG. 7 is a perspective view of the power supply unit 20, which includes an electrically insulating cylindrical body 21 made of an elastic material having an opening 21a, a cord 22, connected to the cord 22, and embedded in the cylindrical body 21. thermostat 23, connection end 27, cord 2
2, and a power supply terminal 25.

FIG. 8 is a perspective view of a pipe heat-retaining heater which is not equipped with a thermostat for controlling the current temperature of the heating element, and which is used by manually pulling out the power plug from the outlet when the pipe heat-retaining heater is not in use.

FIG. 9 is a perspective view of another embodiment of the present invention when the piping is installed. In this embodiment, the cylindrical body 12 of the pipe heat retention heater 11 has comb-like notches 15 parallel to the circumferential direction of the cylindrical body 12.
is formed. Bend portion 10b of tube IO.

The notch 15 corresponding to 10b' is cut away, and the bent portions 10a and lQb are held by the cylinder 12. In this case, as shown in FIG. 9, the entire notch 15 may be removed, or all or part of the remaining notch 15a shown by the chain line may be left in the cover 30. Power supply section 20. The cord 22 is substantially similar to that of the embodiment described in FIGS. 4 and 7.

〔Effect of the invention〕

In the present invention, since a flat, slightly circular heating element is arranged between two parallel conductors, the electrical resistance of the heating element per unit width of the parallel conductors is constant, so piping can be made to any length. The insulation heater can be cut and used. In addition, the configuration does not allow double mounting of heating elements on the piping,
Abnormal fever is completely avoided. In addition, since it is made of an elastic material with openings formed in the longitudinal direction, it can be easily fitted to piping by expanding it, and it does not easily fall off due to its own gravity, so there is no need to hold it with wire, etc.
Overheating and fire caused by electrical shorts are completely prevented.

Furthermore, since there is no need to wrap wires or strips around the pipe as in the past, installation is extremely easy, even if the space between the pipe, the water pipe, and the wall is narrow, for example.

Furthermore, in the present invention, by forming a notch in the cylindrical body and cutting off the notch at a bend, twist, or large diameter part of the pipe, the pipe heat retaining heater can be held integrally with the pipe. In addition, for example, in places where piping cooling conditions are severe, piping insulation heaters can be installed in a spiral shape, which is extremely advantageous in terms of construction.

[Brief explanation of drawings]

FIG. 1 is a perspective view of one embodiment of the present invention, FIG. 2 (A),
(B) is a cross-sectional view and a developed cross-sectional view of FIG. 1, FIG. 3 is a developed view of FIG. 1, FIG. 4 is a perspective view of an embodiment in which the present invention is applied to pipe heat insulation, and FIG. 6 is a perspective view of an embodiment of the present invention applied to a twisted part of a pipe, FIG. 6 is a perspective view of an embodiment of the present invention applied to a spiral pipe, and FIG.
FIG. 8 is a perspective view of another embodiment of the power supply section, and FIG. 9 is a perspective view of another embodiment of the present invention applied to piping. DESCRIPTION OF SYMBOLS 1... Piping heat retention heater, 2... Cylindrical body 3... Parallel conducting wire, 4... Heat generating part 5... Notch part, 10
... Piping 10a... Straight pipe section, 10b... Bent section Patent applicant Kiyoyo Ogawa Masato Tadashi Wakabayashi Figure 4 Figure 5 Figure 6

Claims (8)

[Claims] (1) A cylindrical body made of an elastic waterproof/electrical insulating material with an opening extending the entire length in the axial direction, and two parallel tubes embedded in the cylindrical body extending in the axial direction. A conductive wire, a slightly circular flat heating part electrically connected between the two parallel conductive wires, and a plurality of continuous repeating shapes on the cylindrical body, leaving connection parts symmetrical about the heating part. A piping heat retention heater characterized by comprising a notch portion formed therein. (2) The piping heater according to claim 1, wherein the cylinder has a circular or elliptical cross section. (3) The piping heater according to claim 1 or 2, wherein the width of the heat generating portion is 10 to 30% of the entire circumference of the cylinder. (4) The piping according to any one of claims 1 to 3, characterized in that the length of the notch in the circumferential direction of the cylinder is symmetrically about 30% of the entire circumference of the cylinder. Warm heater. (5) The piping heater according to any one of claims 1 to 4, which can be used by cutting at right angles to the longitudinal direction. (6) The cylindrical body portion corresponding to the notch portion is cut and removed at a bent or twisted portion of the pipe to be installed, and is used as described in any one of claims 1 to 5. Piping insulation heater. (7) The piping heater according to any one of claims 1 to 6, which can be used by being connected in the longitudinal direction. (8) The piping heat-retaining heater according to any one of claims 1 to 7, which is equipped with a piping temperature sensor, a power source, and a means for confirming energization.