Film heater with integral power connection

Abstract

A film heater having an integrated power connection portion according to one embodiment of the present invention is a film heater having a heating portion having a heating element pattern formed on an insulating substrate and a power connection portion connected to a power cable to apply power to the heating portion, wherein the film heater comprises: a flexible planar connection portion protective cover that completely wraps the exterior of the power connection portion, including a part of the power cable connected to the power connection portion, and comprises at least one from the group including silicone, urethane, Teflon, PTFE (Polytetrafluoroethylene), PI (Polyimide), PET (Polyethylene terephthalate), and rubber; and a primary sealing portion formed by ultrasonically bonding the edge portion of the connection portion protective cover.

Description

Technology Field

[0001] The present invention relates to a film heater having an integrated power connection part, and more specifically, to a film heater having an integrated power connection part that is thin, flexible, and highly durable, which can be easily wrapped around fire hydrant pipes indoors, such as in underground parking lots, and is usefully used as a device to prevent freezing and bursting, and which has excellent heat conduction efficiency and improved heating performance by reflecting and concentrating the heat energy of the heating part toward the pipes. Background Technology

[0002] Generally, film heaters refer to heating devices used in home appliances, medical devices, automotive parts, and other industrial fields.

[0003] However, conventional film heaters have a structure in which the heating element is directly exposed on the base film, which not only lacks durability but is also vulnerable to external impacts or scratches, raising concerns that heater performance may significantly deteriorate if the heating element is damaged.

[0004] In addition, due to the aforementioned exposed structure, chemical resistance is insufficient, making it vulnerable to specific chemicals or moisture depending on the material; furthermore, depending on the heating pattern of the heater, heat distribution may not be uniform, and damage may occur due to localized overheating.

[0005] In addition, conventional film heaters are installed as thin surfaces that are attached to areas requiring heat or fixed in direction to transfer radiant heat. However, since heat generation occurs in both directions, heat escapes in unnecessary directions, resulting in reduced heating performance.

[0006] An example of a film radiant heater for resolving these problems is well illustrated in Korean Patent Registration No. 2347136 (hereinafter referred to as the 'prior art').

[0007] Referring to FIG. 1, the conventional film radiant heater (100) disclosed in the prior art comprises a heating element film (10) including a plurality of planar heating elements (40) for radiating radiant heat, a spacer (60), and a reflector (70). The heating element film (10) has a structure in which a plurality of planar heating elements (40), based on a carbon material that generates heat by receiving power and emits radiant heat and far-infrared rays, are spaced apart at regular intervals on a horizontal plane.

[0008] Additionally, the spacer (60) is laminated on the rear surface of a heating element film (10) comprising a plurality of planar heating elements (40), and a plurality of air insulation windows (63) are provided above the planar heating elements (40). The reflector (70) is laminated on the rear surface opposite to the front surface of the spacer (60) on which the heating element film (10) is laminated, and reflects radiant heat and far-infrared rays emitted from the heating element film (10) toward the spacer (60) toward the heating element film (10).

[0009] Accordingly, the conventional film radiant heater (100) of the above-described configuration has a structure in which a spacer (60) having a plurality of air insulation windows (63) is interposed between a heating element film (10) and a reflector (70) to improve radiant heat efficiency, thereby allowing for a reduction in product weight and thickness. Meanwhile, since the reflector (70) is installed on the rear side of the heating element film (10) via the spacer (60), the radiant heat and far-infrared rays that could be lost to the rear side of the heating element film (10) are reflected to the reflector (70) and emitted to the front side of the heating element film (10), thereby improving the radiant heat efficiency of the radiant heat and far-infrared rays.

[0010] However, the conventional film radiant heater (100) disclosed in the above prior art has a structure in which a plurality of planar heating elements (40) partitioned on a horizontal plane are insulated and an air insulation layer (63) and a spacer (60) are vertically stacked in multiple layers on the upper and lower sides of the heating element film (10) respectively to increase radiant heat efficiency, and each planar heating element (40) is horizontally isolated by a plurality of air inlet / outlet holes (11, 71), so the thickness of the film radiant heater (100) is increased and flexibility is reduced, so there was a problem that it could not be wrapped around fire water pipes such as underground parking lots as a freezing or anti-freezing device.

[0011] In addition, as described above, there was a problem in that not only could the thermal conductivity above the planar heating element be reduced due to the complex internal insulation structure, but the possibility of failure also increased if an electrical disconnection occurred between the planar heating elements in a bent state.

[0012] Therefore, there is an increasing demand for film heaters that are thin and flexible, maintaining long-term durability even when wrapped around pipes or similar structures as antifreeze devices, and capable of improving heat generation performance through heat conduction as well as radiant heat and ensuring uniform heat generation performance.

[0013] Meanwhile, as previously described, a conventional film heater is provided with a power connection on one side of the heating element. Typically, the power connection is electrically connected to a lead wire of a power source (not shown) by riveting or soldering, and subsequently, the exterior of the power connection is wrapped in a plastic hard case or the like to protect it from external shocks or physical forces that could cause the wire to break.

[0014] However, as described above, conventional power connection parts with a structure that is wrapped and protected by a hard case or the like inevitably lack flexibility. Consequently, when the film heater is wrapped around, for example, a fire extinguishing water pipe and used as a device to prevent freezing or bursting, the power connection part may bend severely, causing damage to the hard case or a break in the wire inside the power connection part, which creates a persistent problem of vulnerability to fire caused by freezing or breakage of the pipe. Therefore, there is an urgent need for improvement regarding this. Prior art literature

[0015] (Patent Document 0001) KR 2347136 B The problem to be solved

[0016] Accordingly, the present invention is designed to resolve the above-mentioned problems and aims to provide a film heater having an integrated power connection that is thin, flexible, and highly durable, which can be easily wrapped around firefighting water pipes indoors, such as in underground parking lots, and is usefully used as a device to prevent freezing and bursting, and which has excellent heat conduction efficiency and improved heating performance through heat conduction and radiant heat by reflecting and concentrating the heat energy of the heating part toward the pipe. means of solving the problem

[0017] According to one embodiment, a film heater having an integrated power connection part of the present invention for achieving the above-mentioned purpose comprises a heating part having a heating element pattern formed on an insulating substrate and a power connection part connected to a power cable to apply power to the heating part, wherein the film heater comprises: a flexible surface-shaped connection part protective cover that completely wraps the exterior of the power connection part, including a part of the power cable connected to the power connection part, and includes at least one from the group comprising silicone, urethane, Teflon, PTFE (Polytetrafluoroethylene), PI (Polyimide), PET (Polyethylene terephthalate), and rubber; and a primary sealing part formed by ultrasonically bonding the edge portion of the connection part protective cover.

[0018] According to one embodiment, a secondary sealing portion is further formed between the power cable and the connection part protection cover.

[0019] According to one embodiment, the secondary sealing part is characterized by being a fused rubber tape filled between the power cable and the connection part protective cover.

[0020] According to one embodiment, the heating member further comprises: a heat-reflecting film coupled to one side of the heating member, wherein a metal layer for heat reflection is formed on one side of a synthetic resin base film; a heat-blocking film coupled to the opposite side of the heating member of the heat-reflecting film; and a protective cover that completely encloses and seals the exterior of the heating member, including the power connection part, by including the heat-reflecting film and the heat-blocking film.

[0021] According to one embodiment, the power line of the power cable is electrically connected to the power terminal of the power connection part, and the ground terminal of the power connection part is connected to the metal layer of the heat-reflective film, and the ground line of the power cable is connected to the ground terminal.

[0022] According to one embodiment, the heat-blocking film is a PET (Polybutylene Terephtalate) film of a certain thickness, and the heat-reflecting film is an aluminum metal layer integrally bonded on the PET film.

[0023] According to one embodiment, the connection part protection cover is characterized by being formed by overlaying it on a protection cover that surrounds the power connection part.

[0024] According to one embodiment, the primary sealing portion is characterized by being formed by pressing and compressing the connection portion protective cover and then ultrasonically bonding the edge portion of the connection portion protective cover.

[0025] According to another embodiment, the connection part protection cover is characterized by wrapping and sealing the power connection part in a state where it is integrally extended on one side of the protection cover. Effects of the invention

[0026] The present invention, as described above, has the beneficial effect of preventing pipe freezing and fire caused by damage or breakage of the power connection part, as the power connection part is combined integrally with a film heater without a separate hard case to protect the power connection part, is thin and flexible, and when easily wrapped around firefighting water pipes indoors, such as in underground parking lots, and used as a freezing and anti-freezing device, the power connection part can maintain excellent durability for a long time without being damaged or broken due to bending or twisting.

[0027] In addition, the present invention not only has excellent thermal conductivity efficiency but also has the effect of improving combined heating performance through thermal conduction and radiant heat by reflecting and concentrating the thermal energy of the heating element toward the pipe.

[0028] In addition, the present invention can improve the quality of film heater products by ensuring uniform heating performance of the heating part, and can increase the efficiency of the manufacturing process, which has an effect advantageous for mass production.

[0029] In addition, the present invention has the effect of being widely applicable to various industrial fields, such as freezing / freezing prevention devices for fire water pipes in underground parking lots, vehicle seat heaters, medical heating pads, temperature control devices for electronic products, indoor heating systems, and industrial heat treatment devices, as it ensures flexibility along with a thin thickness. Brief explanation of the drawing

[0030] FIG. 1 is a cross-sectional view of a conventional film radiating heater disclosed in a prior art document. FIG. 2 is a conceptual diagram of a film heater having an integrated power connection part of the present invention. FIG. 3a is a plan view showing the heating element inside the film heater of the present invention. FIG. 3b is a diagram showing a state in which a heat-reflective film is attached to one side of the heating element of FIG. 3a. FIG. 3c is a state in which the heating element and the exterior of the heat-reflective film of FIG. 3b are wrapped by a protective cover and sealed. FIG. 3d is a state in which the exterior of the power connector of FIG. 3c is wrapped and sealed by a connector protective cover according to one embodiment. FIG. 4 is a flowchart showing a method for manufacturing a film heater of the present invention according to one embodiment. FIG. 5 is a state in which the exterior of the power connector of FIG. 3c is wrapped and sealed by an integrated connector protective cover according to another embodiment. FIG. 6 is a flowchart showing a method for manufacturing a film heater of the present invention according to another embodiment. Specific details for implementing the invention

[0031] The terms used herein are used merely to describe specific embodiments and are not intended to limit the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, terms such as “comprising,” “having,” or “having” are intended to indicate the existence of the features, numbers, steps, actions, components, parts, or combinations thereof described herein, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0032] Unless otherwise defined in this specification, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which the present invention pertains.

[0033] Terms such as those defined in commonly used dictionaries should be interpreted as having meanings consistent with their meanings in the context of the relevant technology, and should not be interpreted in an ideal or overly formal sense unless explicitly defined in this specification.

[0034] Hereinafter, the configuration and operational relationship of a film heater with improved heating performance according to an embodiment of the present invention will be examined in detail with reference to the attached drawings.

[0035] FIG. 2 is a conceptual diagram of a film heater with improved heating performance according to the present invention, FIG. 3a is a plan view showing a heating part inside the film heater according to the present invention, FIG. 3b is a diagram showing a state in which a heat-reflective film is attached to one side of the heating part of FIG. 3a, FIG. 3c is a diagram showing a state in which the heating part of FIG. 3b and the exterior of the heat-reflective film are wrapped by a protective cover and sealed, FIG. 3d is a diagram showing a state in which the exterior of the power connection part of FIG. 3c is wrapped by a connection part protective cover and sealed according to one embodiment.

[0036] Referring to FIGS. 2 to 3d above, the configuration according to one embodiment of the present invention is largely composed of a film heater (1000) with improved heating performance, a heat-reflecting film (1200), a heat-blocking film (1300), and a protective cover (1400A, 1400B).

[0037] First, the heating element (1100) may be in the form of a heating element pattern (1120) formed between a pair of insulating substrates (1110, 1130) according to one embodiment, and a power connection part (1500) for applying power (not shown) to the heating element pattern (1120) is provided on a part of the edge of the insulating substrates (1110, 1130).

[0038] According to one embodiment, the heating element pattern (1120) may be a linear metal heating element pattern (1120) formed on a base insulating substrate (1110) as shown in FIG. 3a.

[0039] Accordingly, when power (not shown) is applied to the heating element pattern (1120) through the power connection part (1500), the heating element pattern (1120) heats up and releases thermal energy. At this time, the material of the heating element pattern (1120) may be a metal-based paste having a specific electrical resistance, and may be adopted from a group including, for example, silver (Ag), copper (Cu), or carbon nanotube (CNT)-based ink pastes.

[0040] Also, referring to FIG. 3b, the heat-reflective film (1200) has a metal layer (1220) formed on one side of the base film (1210) to reflect radiant heat energy, and is coupled to one side of the heating element (1100) to provide heat shielding so that heat cannot escape to one side of the heating element (1100).

[0041] According to one embodiment, the heat-reflective film (1200) may be an aluminum metal layer (1220) formed by depositing an aluminum thin film to a certain thickness on one side of a PET (Polybutylene Terephtalate) film as a base film (1210). In this case, the metal layer (1220) of the heat-reflective film (1200) is electrically connected to a ground line (EL) of a power source (not shown).

[0042] Thus, the metal layer (1220) of the heat-reflective film (1200) serves to reflect radiant heat energy generated from the heating element (1100) back toward the heating element (1100), and at the same time serves as an earth plate for the power source (not shown). If a leakage current occurs inside the film heater (1000) of the present invention, the leaked current is grounded to the earth through the metal layer (1220) of the heat-reflective film (1200) and the ground line (EL) of the power cable (PC).

[0043] Additionally, the heat-blocking film (1300) is attached to the opposite side of the heat-reflecting film (1200) of the heat-generating portion (1100).

[0044] The above heat-blocking film (1300) is a component for heat shielding to prevent heat energy generated in the heating element (1100) from escaping to the outside of the film heater (1000) by heat conduction, and according to one embodiment, the heat-blocking film (1300) may be a PET film having a certain thickness.

[0045] Alternatively, according to another embodiment, the heat-blocking film (1300) is not provided separately, and a PET film of a heat-reflective film combined with a metal layer (1220) may serve as the heat-blocking film. In this case, the heat-reflective film (1200) and the heat-blocking film (1300), which are components of the present invention, are integrated into one, making it possible to implement a thinner film heater (1000). Furthermore, when the film heater (1000) of the present invention is wrapped around, for example, a fire hydrant pipe (not shown) and used as a device to prevent freezing or bursting, it can provide greater flexibility.

[0046] Accordingly, the heating element (1100), heat reflective film (1200), and heat blocking film (1300) described above are implemented with a thin thickness so that they can be wrapped and adhered to the outer surface of, for example, a fire extinguishing water pipe as a freezing and burst prevention device, thereby providing greater flexibility. To this end, unlike the prior art previously examined, the interiors of the heating element (1100), heat reflective film (1200), and heat blocking film (1300) may be in a form that is airtightly combined as a single unit without any voids.

[0047] Additionally, the protective cover (1400A, 1400B) completely wraps and seals the exterior of the heating part (1100), excluding the power connection part (1500), including the heat reflective film (1200) and the heat blocking film (1300).

[0048] To this end, the protective cover (1400A, 1400B) may be made of a flexible material that can withstand high temperatures without reducing the flexibility characteristic of the film heater (1000) of the present invention, and for example, a flexible planar body with a thickness of 0.3 mm to 5 mm, such as silicone, urethane, Teflon, PTFE, PI, PET, rubber, etc., may be adopted.

[0049] Also, referring to FIG. 3d, the power connection part (1500) of the film heater (1000) of the present invention further has a connection part protective cover (1600), a primary sealing part (1610), and a secondary sealing part (1620) formed therein.

[0050] According to one embodiment, the connection part protection cover (1600) may be a flexible sheet that covers the entire exterior of the power connection part (1500), including a part of the power cable (PC) connected to the power connection part (1500), and may be a flexible sheet that includes at least one material adopted from the group comprising silicone, urethane, Teflon, PTFE (Polytetrafluoroethylene), PI (Polyimide), PET (Polyethylene terephthalate), and rubber.

[0051] At this time, preferably, the connection part protection cover (1600) is formed by additionally overlaying it on the exterior of the protection cover (1400A, 1400B) that already surrounds the power connection part (1500). As a result, the power connection part (1500) is double-wrapped by the connection part protection cover (1600) overlapping the previously formed protection cover (1400A, 1400B), thereby further improving the sealing power of the power connection part (1500) to shield against moisture penetration from the outside.

[0052] In addition, the primary sealing portion (1610) may be an ultrasonically welded portion formed by ultrasonically joining the edge portion of the connection portion protective cover (1600).

[0053] According to one embodiment, when a planar silicone rubber is used as the connection part protection cover (1600), the silicone rubber is compressed, and then the edge portion of the silicone rubber is fused into a single unit by applying vibration energy of a certain frequency or higher (typically 18 kHz or higher) using an ultrasonic welding machine (not shown).

[0054] That is, the first sealing portion (1610) can be formed by pressing and compressing the connection portion protection cover (1610) as described above and then ultrasonically bonding the edge portion of the connection portion protection cover (1600). By doing so, the air inside the connection portion protection cover (1600) is removed, thereby making the thickness of the power connection portion (1500) thinner, and the thinned power connection portion (1500) can be given greater flexibility.

[0055] Additionally, the secondary sealing portion (1620) may be a fused rubber tape filled between the power cable (PC) and the connection part protection cover (1600).

[0056] More specifically, according to one embodiment, the secondary sealing part (1620) may be a self-bonding rubber insulation tape, and the process of forming the secondary sealing part (1620) may be performed in the order of first attaching or wrapping the self-bonding rubber insulation tape between the power cable (PC) and the connection part protection cover (1600) to seal it, and then using the connection part protection cover (1600) to completely wrap the power connection part (1500).

[0057] Prior to this, as described above, the power line (PL) of the power cable (PC) is electrically connected to the power terminal (1510) of the power connection part (1500), and the ground terminal (1520) of the power connection part (1500) is connected to the metal layer (1220) of the heat reflective film (1200), and the ground line (EL) of the power cable (PC) is connected to the ground terminal (1520).

[0059] FIG. 4 is a flowchart showing a method for manufacturing a film heater of the present invention according to one embodiment.

[0060] Referring to FIG. 4 above, the method for manufacturing a film heater (1000) with improved heating performance according to the present invention can be carried out by the following steps according to one embodiment.

[0061] Step (S100): Form a heating element (1100) in the form of a flexible film.

[0062] Specifically, this step (S100) can be performed by the following detailed steps.

[0063] Step (S110): As a base substrate, a flexible base insulating substrate (1110) is prepared.

[0064] According to one embodiment, the base insulating substrate (1110) may include a flexible and heat-resistant polyester (PET) film, a polyamide (PI) film, or a polytetrafluoroethylene (PTFE) film. Additionally, the thickness of the base insulating substrate (1110) may be selectively formed between 12.5 μm and 125 μm.

[0065] Step (S120): A metal heating element pattern (1120) is formed on the upper surface of the base insulating substrate (1110) by a wet printing method.

[0066] According to one embodiment, the present step involves designing a heating element pattern (1120) using CAD software, wherein the material used for the heating element pattern (1120) includes an ink-type paste based on silver (Ag), copper (Cu), or carbon nanotubes (CNT). Additionally, the ink-type paste forms a heating element pattern (1120) on a base insulating substrate (1110) by applying a wet printing method, such as screen printing, inkjet printing, or roll-to-roll printing.

[0067] Step (S130): The base insulating substrate (1110) on which the metal heating element pattern (1120) is formed is placed in an oven and dried for a certain period of time to cure the linear metal heating element pattern (1120).

[0068] According to one embodiment, the present step involves first placing a base insulating substrate (1110) on which a heating element pattern (1120) is formed into a drying oven (not shown) and drying it at a high temperature of 80 to 120°C for about 30 minutes. Afterward, the base insulating substrate (1110) on which the metal heating element pattern (1120) has been formed and which has been dried is placed into a curing device (not shown) and heat-treated at a high temperature of 150 to 200°C for about 1 hour to strengthen the adhesion of the heating element pattern (1120).

[0069] Step (S140): Another flexible encapsulated insulating substrate (1130) is attached to the upper surface of the base insulating substrate (1110) on which the metal heating element pattern (1120) is formed, and the process is finished.

[0070] That is, this step is a step of forming an encapsulation layer on a heating element pattern (1120), and according to one embodiment, the heating element pattern (1120) is protected from the external environment by bonding another encapsulation insulating substrate (or protective film, 1130) on the heating element pattern (1120) of the base insulating substrate (1110) formed in the previous step (S130).

[0071] Alternatively, according to another embodiment, the present step may involve forming a dielectric layer of thin film by applying an insulating material having insulating performance on a heating element pattern (1120) instead of the other encapsulated insulating substrate (1130) described above, followed by UV curing or thermal curing.

[0073] Step (S200): A heat-reflective film (1200) is prepared in which a metal layer (1220) for heat reflection is formed on one side of a synthetic resin base film (1210), and the heat-reflective film (1200) is attached to one side of the heating element (1100).

[0074] According to one embodiment, the heat-reflective film (1200) of step (S200) may be formed by depositing an aluminum metal layer (1220) to a certain thickness on one side of a PET (Polybutylene Terephtalate) film as a base film (1210). That is, the heat-reflective film (1200) may be an aluminum-deposited PET (Aluminized polyester) film, and the thickness may be formed to be 10 to 20 μm depending on the heating performance of the desired film heater (1000).

[0076] Step (S300): A heat-blocking film (1300) is attached to the opposite side of the heat-reflecting film (1200) of the heat-generating part (1100).

[0077] According to one embodiment, the heat-blocking film (1300) may also be a PET film having a certain thickness, similar to the heat-reflective film (1200).

[0078] Alternatively, according to another embodiment, the heat-blocking film (1300) is not provided separately, and a PET film, which is the base film (1210) of a heat-reflective film (1200) combined with a metal layer (1220), may serve as the heat-blocking film. That is, the heat-blocking film (1300) is a PET film of a certain thickness, and the heat-reflective film (1200) may be an aluminum metal layer integrally combined on the PET film.

[0079] At this time, as described above, when the PET film of the heat-reflective film (1200) also serves as a heat-blocking film (1300), it is preferable that the thickness of the PET film be formed to an appropriate thickness considering the heat-blocking performance and flexibility intended by the film heater of the present invention.

[0080] Accordingly, as described above, by the combination configuration of the heat-reflective film (1200) and the heat-blocking film (1300) which are separately provided or integrated to form a single unit, the heat energy generated by radiation or conduction from the film heater (1000) of the present invention can be concentrated toward the heating target (e.g., fire extinguishing water pipe, not shown), and accordingly, the heating performance and heat transfer efficiency of the film heater (1000) of the present invention can be significantly improved.

[0082] Step (S400): Connect a power source (not shown) to the power connection part (1500) of the heating part (1100).

[0083] That is, as illustrated in FIGS. 3a and 3b, the power line (PL) of the power cable (PC) is connected to the power terminal (1510) of the power connection part (1500), and the ground line (EL) of the power cable (PC) is also electrically connected to the ground terminal (1520) of the power connection part (1500) connected to the metal layer (1220) of the heat-reflective film (1200).

[0084] Accordingly, the metal layer (1220) of the heat-reflective film (1200) serves to reflect the radiant heat energy generated from the heating element (1100) back toward the heating element (1100), and at the same time serves as an earth plate to ground the leakage current inside the film heater (1000).

[0086] Step (S500): The exterior of the heating element (1100), including the power connection part (1500) of the heating element (1100), the heat reflective film (1200), and the heat blocking film (1300) is completely wrapped and sealed with a protective cover (1400A, 1400B).

[0087] Specifically, this step (S500) can be performed by the following detailed steps.

[0088] Step (S510): As a material for the protective cover (1400A, 1400B), at least one selected from the group including silicone, urethane, Teflon, PTFE, PI, PET, and rubber sheet is cut and prepared to be larger than the planar area of ​​the heating element (1100), heat reflective film (1200), and heat blocking film (1300). At this time, the thickness of the protective cover (1400A, 1400B) may be 0.3 to 5 mm.

[0089] Step (S520): After applying an adhesive (e.g., silicone adhesive) to both sides of the edges of the heating element (1100), heat reflective film (1200), and heat blocking film (1300), a protective cover (1400A, 1400B) is placed on top of it. Then, using a press machine (not shown), the edges of the heat reflective film (1200) and heat blocking film (1300) to which the adhesive has been applied are pressed and the adhesive is cured to seal the protective cover (1400A, 1400B) in the first stage (1410, see FIG. 2 and 3c).

[0090] Step (S530): A protective cover (1400A, 1400B) is secondarily sealed (1420) by ultrasonic bonding along the edge lines of the first sealed heat-reflective film (1200) and the heat-blocking film (1300).

[0091] That is, according to this step, the sealing power of the side edge line that is secondarily sealed (1420) by the protective cover (1400A, 1400B) is further strengthened, thereby further improving the side waterproofness and durability of the film heater (1000) of the present invention.

[0092] Additionally, although not shown in the drawings, after performing the secondary sealing (1420) by the ultrasonic bonding, the excess portion outside the primary and secondary sealing portions (1410, 1420) of the protective cover (1400A, 1400B) can be cut and removed using a cutter (not shown), and the side can be thoroughly sealed once again by applying an adhesive (e.g., silicone adhesive) to the cut surface of the protective cover (1400A, 1400B) from which the excess portion has been removed.

[0094] Step (S600): The exterior of the power connection part (1500) is completely wrapped with a connection part protection cover (1600) to provide double sealing.

[0095] According to one embodiment, the connection part protection cover (1600) may be a flexible sheet that covers the entire exterior of the power connection part (1500), including a part of the power cable (PC) connected to the power connection part (1500), and may be a material adopted from the group including silicone, urethane, Teflon, PTFE (Polytetrafluoroethylene), PI (Polyimide), PET (Polyethylene terephthalate), and rubber.

[0096] At this time, preferably, the connection part protection cover (1600) is formed by additionally overlaying it on the exterior of the protection cover (1400A, 1400B) that already surrounds the power connection part (1500). As a result, the power connection part (1500) is double-wrapped by the connection part protection cover (1600) overlapping the previously formed protection cover (1400A, 1400B), thereby further improving the sealing power of the power connection part (1500) to shield against moisture penetration from the outside.

[0097] In addition, when using a silicone rubber surface as a connection part protection cover (1600) for the first sealing part (1610), the silicone rubber is compressed, and then vibration energy of a certain frequency or higher (typically 18 kHz or higher) is applied to the edge portion of the silicone rubber using an ultrasonic welding machine (not shown) to melt the compressed edge portion of the silicone rubber with vibration energy and fuse it as a single unit.

[0098] Additionally, the secondary sealing portion (1620) may be a fused rubber tape filled between the power cable (PC) and the connection part protection cover (1600).

[0099] According to one embodiment, the process of forming the secondary sealing part (1620) may be performed in the order of first attaching or wrapping a self-bonding rubber insulation tape between the power cable (PC) and the connection part protection cover (1600) to seal it, and then wrapping the power connection part (1500) entirely using the connection part protection cover (1600).

[0101] FIG. 5 is a diagram showing the external appearance of the power connection part of FIG. 3c wrapped and sealed by an integrated connection part protective cover according to another embodiment, and FIG. 6 is a flowchart showing the method of manufacturing the film heater of the present invention according to another embodiment.

[0102] Meanwhile, according to another embodiment, the integrated connection part protection cover (1700) is not provided separately from the protection cover (1400A, 1400B) as described above in one embodiment, but can wrap and protect the power connection part (1500) in a state where it is integrally extended on one side of the protection cover (1400A, 1400B).

[0103] Accordingly, in step (S510) shown in FIG. 6, the integrated connection part protective cover (1700) completely wraps and seals the exterior of the heating part (1100), the heat-reflective film (1200), and the heat-blocking film (1300) of the heating part (1100) with protective covers (1400A, 1400B), and together with this, wraps and seals the power connection part (1500) using the integrated connection part protective cover (1700) which is integrally extended on one side of the protective covers (1400A, 1400B). Subsequently, a first sealing part (1710) and a second sealing part (1720) are formed in the integrated connection part protective cover (1700), similar to the above-described embodiment.

[0104] According to the configuration of the other embodiment above, by using a protective cover (1400A, 1400B) and an integrated connection part protective cover (1700) to wrap and seal the heating part (1100), heat reflective film (1200), heat blocking film (1300), and power connection part (1500) at once, the process can be simplified compared to the first embodiment described above (steps S500 and S600 of the first embodiment are performed at once as step S510 of the other embodiment), and the process time can be shortened to improve process efficiency.

[0106] The present invention includes a film heater having an integrated power connection unit manufactured according to the steps described above in this specification. The film heater (1000) of the present invention is thin and flexible, and the power connection unit is integrally combined with the film heater without using a separate hard case to protect the power connection unit as in the past. In particular, when easily wrapped around firefighting water pipes indoors, such as in underground parking lots, and used as a freezing and anti-freezing device, the power connection unit can maintain excellent durability for a long time without being damaged or disconnected due to bending or twisting, thereby preventing freezing and fire in the pipes caused by damage or disconnection of the power connection unit.

[0107] In addition, the present invention not only has excellent thermal conductivity efficiency but also achieves the effect of improving combined heating performance through thermal conduction and radiant heat by reflecting and concentrating the thermal energy of the heating element toward the pipe.

[0108] In addition, the present invention can improve the quality of film heater products by ensuring uniform heating performance of the heating part, and can increase the efficiency of the manufacturing process, thereby obtaining an effect advantageous for mass production.

[0109] In addition, the present invention ensures flexibility along with a thin thickness, thereby enabling wide application in various industrial fields, such as anti-freezing devices for fire water pipes in underground parking lots, vehicle seat heaters, medical heating pads, temperature control devices for electronic products, indoor heating systems, and industrial heat treatment devices.

[0111] Furthermore, the present invention is not limited solely to the embodiment described above. Since the same effect can be achieved even when the detailed configuration, number, or arrangement structure of the device is changed, it is hereby specified that those skilled in the art can add, delete, or modify various configurations within the scope of the technical concept of the present invention. Explanation of the symbols

[0112] 1000 : (The present invention) Film heater 1100 : Heating part 1110, 1120, 1130: Base insulating substrate, heating element pattern, encapsulation insulating substrate 1200 : Heat reflective film 1210, 1220: Base film, metal layer 1300 : Heat-blocking film 1400A, 1400B: Protective cover 1410, 1420: Primary seal (thermal sealing), secondary seal (ultrasonic bonding) 1500 : Power connector 1510, 1520: Power terminal, ground terminal 1600 : Connection part protective cover 1610, 1620: Primary seal (ultrasonic bonding), secondary seal (fusion rubber tape) 1700 : Integrated connection protection cover 1710, 1720: Primary seal (ultrasonic bonding), secondary seal (fusion rubber tape) PC, PL, EL: Power cable, power line, ground line

Claims

Claim 1 A film heater comprising a heating element having a heating element pattern formed on an insulating substrate and a power connection part connected to a power cable to apply power to the heating element, wherein the heating element comprises: a flexible planar connection part protective cover that completely wraps the exterior of the power connection part, including a portion of the power cable connected to the power connection part, and comprises at least one from the group including silicone, urethane, Teflon, PTFE (Polytetrafluoroethylene), PI (Polyimide), PET (Polyethylene terephthalate), and rubber; and a primary sealing part formed by ultrasonically bonding the edge portion of the connection part protective cover; wherein the heating element comprises: a heat-reflecting film composed of a synthetic resin base film and a metal layer for heat reflection formed on one side of the base film and coupled to one side of the heating element; and a heat-blocking film provided separately from the heat-reflecting film and coupled to the side of the heat-reflecting film opposite to the heating element. A film heater having an integrated power connection, wherein a protective cover that completely encloses and seals the exterior of a heating element including a power connection, including the heat-reflective film and the heat-blocking film, is further combined. Claim 2 A film heater having an integrated power connection part, characterized in that, in claim 1, a secondary sealing part is further formed between the power cable and the connection part protective cover. Claim 3 A film heater having an integrated power connection part, characterized in that, in claim 2, the secondary sealing part is a fused rubber tape filled between the power cable and the connection part protective cover. Claim 4 delete Claim 5 A film heater having an integrated power connection unit, characterized in that, in claim 1, the power line of a power cable is electrically connected to the power terminal of the power connection unit, and the ground terminal of the power connection unit is connected to the metal layer of the heat-reflective film, and the ground line of the power cable is connected to the ground terminal. Claim 6 A film heater having an integrated power connection part, wherein, in claim 1, the heat-reflective film is composed of an aluminum metal layer integrally bonded on a PET (Polybutylethylene Terephtalate) film of a certain thickness, and the heat-blocking film is not provided separately from the heat-reflective film, and the PET film of the heat-reflective film serves as the heat-blocking film. Claim 7 A film heater having an integrated power connection part, characterized in that, in claim 1, the connection part protective cover is formed by overlaying it on a protective cover that surrounds the power connection part. Claim 8 A film heater having an integrated power connection part, characterized in that, in claim 1, the primary sealing part is formed by pressing and compressing the connection part protective cover and then ultrasonically bonding the edge portion of the connection part protective cover. Claim 9 A film heater having an integrated power connection part, wherein, in claim 1, the connection part protective cover surrounds and seals the power connection part in a state in which it is integrally extended on one side of the protective cover.

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