CN210225773U

CN210225773U - Assembly of PTC heating device and contain its electrical apparatus

Info

Publication number: CN210225773U
Application number: CN201821390173.9U
Authority: CN
Inventors: Guoping Jiang; 蒋国屏
Original assignee: Wuxi Guowei Ceramic Electrical Appliances Co Ltd
Current assignee: Wuxi Guowei Ceramic Electrical Appliances Co Ltd
Priority date: 2018-08-21
Filing date: 2018-08-21
Publication date: 2020-03-31
Anticipated expiration: 2028-08-21

Abstract

The utility model discloses a sub-assembly of PTC heating device, including PTC heating device, first installing support, second installing support, the introduction power pencil of having connected temperature controller and temperature fuse, first installing support has pedestal and closing cap, the electrode slice of different polarity draws forth the end and the electrified department cladding in surface of the coupling part of connecting power pencil has insulating cover, insulating cover with the electrode slice draws forth the end and the electrified body surface of the coupling part of connecting power pencil has all coated temperature resistant, insulating sealed glue. The utility model discloses very big improvement sealed and insulating properties, improved batch production's maneuverability and technology uniformity, improved production efficiency greatly. Under the environment that the electric connection part and the power line leading-out terminal are completely immersed in water, the electric leakage of the electrified part of the heating device and the surface of the heating device can be still ensured. The problems of water seepage and electric leakage of the heater used in a humid environment are thoroughly solved, and the waterproof performance, the use safety and the use reliability are fundamentally solved.

Description

Assembly of PTC heating device and contain its electrical apparatus

Technical Field

The utility model relates to a thermal sensitive ceramic heater, in particular to a combined piece of a PTC heating device.

Background

A support for a PTC thermal sensitive ceramic electric heater and the PTC electric heater (publication No. CN201174784) comprise a mounting surface and a supporting surface, wherein a concave cavity for mounting and fixing a heating body is arranged on the supporting surface, the bottom of the concave cavity is also provided with a cavity which extends inwards and is used for placing a power supply leading-out end connecting wire of the heating body, and a wire leading-out hole is arranged on the supporting surface at the bottom of the cavity. And a through hole for placing the fuse is arranged on one side wall of the supporting surface.

Through this technical scheme can reach and combine the fuse in the support and prevent that it from connecting in the support periphery and influencing the security, but because it still installs on a lateral wall of holding surface, its connecting wire still can twine in the support outside, and the power lead still has the hidden danger that becomes flexible, drops under the exogenic action.

A PTC heater supporting seat and a PTC heater (publication number: CN200920235929) comprise a seat body, a cover plate and a screw; the base body is fixedly connected with the cover plate through screws; a cavity with an opening on one side is arranged in the seat body, and an upper spacing wall and a lower spacing wall are arranged in the cavity; the upper wall of the interval is positioned between the heating body of the PTC heater and the temperature controller; the lower wall of the interval is positioned between the heating body of the PTC heater and the temperature fuse.

Can install temperature controller and temperature fuse in the support through this technical scheme, solve the reliability problem of temperature controller and fuse location. However, the lead-out wires are easy to loosen and fall off under the repeated pulling of external force, and the electrified parts of the connecting surfaces of the two electrode plates and the wire group with different polarities also cause short circuit and contact sparking or loosening caused by poor crimping.

The PTC heater (publication number: 104053255A) shares a tailstock and an electrical appliance connecting seat with more than two heaters, and a temperature controller and a temperature fuse are fixed in the electrical connecting seat of a bare circuit and then are inserted into an electrical plug cavity and an electrical screen connecting seat cover. The technology can solve the problem of positioning of the temperature controller and the fuse in the tail seat of the electric connecting seat, but can still not solve the problems of safety and reliability in the aspects of displacement, mutual interference and the like between parts in the support seat body and between power supply leads.

Above-mentioned prior art all has thermal ceramic heater power connecting wire to draw back and does not have effectual insulating fixed, easily receives to draw the impression, and the problem that the inside power connecting wire of installing support also easily receives the outside influence of drawing simultaneously.

In addition, the existing thermal sensitive ceramic heater for the cabinet air conditioner adopts a single group or multiple groups of materials connected in parallel, the power connecting wires of the thermal sensitive ceramic heaters are mutually interfered and are not effectively insulated and fixed after being led out, and the thermal sensitive ceramic heaters are easily subjected to falling and short-circuit safety accidents caused by the influence of the assembly, transportation and drawing of the whole machine.

An electric PTC liquid heater (publication No. CN2612898Y), wherein the power line is connected with the electrode and supplies power to the electrode, and the power line is connected with the outside through the power line inlet of the metal shell.

By adopting the technical scheme, the power line is directly connected with the electrode, so that the contact resistance is large, and the connection point of the power line is easy to fall off under the action of external force.

A PTC heating quick electric water heater (publication No. CN2742335Y) has a lead wire connected to an insert on a heating device.

By adopting the technical scheme, the safety of the PTC heater can be ensured only by completing the connection of the lead and the PTC electrode plate under the help of the inserting piece, the inserting spring and the sheath, meanwhile, the inserting piece is very high in inserting requirement, and if the inserting piece is not connected with the conjunction part of the inserting piece, the inserting piece is easy to fall off from the PTC electrode plate, so that the heater is damaged.

A PTC heating element (publication No. CN2684506Y) having a fastening terminal, wherein a cramp is provided on the terminal, and the cramp is connected to an electrode plate by punching. By adopting the technical scheme, the buckle sheet is equivalent to an inserting sheet, the distance of stamping needs to be adjusted in real time, the butt joint of the inserting sheet and the inserting spring is difficult to avoid contact gaps, if the connecting part is not connected with the conjunction part, the inserting sheet is easy to fall off from the PTC electrode sheet or the butt joint inserting spring to cause that the heater is not conducted, and the real-time adjustment needs to be carried out by more workers, thus the cost is increased.

In addition, the prior art also adopts a connection scheme of stamping a connecting sheet with a flanging pressing surface or a wrap angle pressing surface and an electrode sheet of a heating strip, although the scheme can solve the problem of reliable pressing of a line group and the connecting sheet, the flanging pressing surface or the wrap angle pressing surface and the electrode sheet are in surface contact and slightly uneven in mutual fit, the matching is easy to loose, and the loosening is caused. In addition, the plane punch of the punching die simultaneously applies impact pressure to two sides of the flanging or the wrap angle, and because the contact positions of the electrode plate and the two sides of the flanging or the wrap angle are in line contact, indentation is also concentrated on the contact positions, and the punching die has slight unevenness, the electrode plate can be damaged and broken on the indentation line, and the whole set of heating strips and wire sets can be scrapped.

In summary, the following steps: the connection mode of the power line and the electrode plate in the prior art has various potential safety and reliability hazards such as poor contact, loose compression joint, damaged stamping and the like.

The prior art is as follows: conductive adhesive is arranged between the heating sheet and the electrode plate, and the adhesive strength of the adhesive is greatly reduced because the conductive adhesive contains a large amount of metal conductive powder. 2. The silica gel which is rapidly and naturally solidified at room temperature is used, the production and storage cost is high, and the use is inconvenient. 3. The existing heating core forms a lateral groove after rolling pressure, and has positive effects of improving the contact between a heating element and an electrode plate and the heating surface of an aluminum tube and improving the heat efficiency.

The prior art has the following defects: 1, new industry CN 00221004: (1) although various insertion modes such as forward, backward, leftward or rightward insertion modes are set, the temperature-control temperature-sensing surface is required to be tightly attached to a radiating strip with an electrified surface, so that safety accidents such as short circuit and electric leakage are easy to occur, and the temperature-control temperature-sensing surface is unreliable and difficult to operate and install. (2) The two jacks for temperature control and fusing respectively penetrate into the inner wall of the concave cavity of the bracket, so that the power supply lead and the electric connection point can only be exposed outside the bracket. (3) The cover plate is only used for supporting the positioning function of the temperature controller, the problem that the connection point of the electrified part is exposed cannot be solved, and great hidden danger of safety and reliability in use is brought. 2, xuchengdong CN 201420064071: the cover plate is exposed in the space on the surface of the bracket, so that water drops are easy to infiltrate into the cavity of the positioning temperature control device and the fuse, thereby bringing safety hidden troubles. 3, national power 200920235929: (1) the temperature control is positioned in the cavity of the bracket seat body, the temperature change of the temperature sensing surface of the temperature controller under the ventilation working state of the heating device and the difference of the dry burning state when the temperature is abnormal are not obvious, and the temperature of the temperature sensing surface can reach the protection temperature only by long recovery time. (2) The temperature difference between the ventilation state and the dry-burning state is not obvious, and the malfunction is easily caused. (3) The temperature control cavity is arranged in the seat body of the bracket, the occupied space is large, the interference of power lines and connecting points among different polarities in the cavity of the seat body is easily caused, and major safety accidents such as short circuit or creepage and the like occur.

1. National patents CN204741574U and CN 104797015A: (1) the cover plate is not provided with an extension surface and a wire harness of the second through hole (2) is not provided with a sealing ring, the wire harness is positioned by binding, and the looseness is easy and the reliability is not high.

The prior art is as follows: (1) and no sealant is arranged in the cavity of the tail support, so that condensed water generated by cold and hot shock of the ambient temperature during the working of the heater easily permeates into the tail aluminum tube heating element to cause short circuit. (2) Linzhi CN302536477S, the afterbody has unsealed step, can't hold sealed glue. (3) The tail of the aluminum tube heating body is flush with the radiator or lower than the tail of the radiator.

The prior art is as follows: lattice force CN 20101024587: (1) all power supply contacts are exposed on the surface of the bracket, the problem of electric leakage in sealing and use in a wet state cannot be solved, and the use is unsafe. (2) The joint of the bracket and the heater has no chamfer or groove, (3) the joint has no sealant, the gap of the joint is easy to seep water, the sealing performance can not be ensured, the problems of water seepage and electric leakage in the use in the moisture environment can not be solved, and the use is unsafe.

SUMMERY OF THE UTILITY MODEL

Utility model purpose: the utility model aims to solve the problem of the intraductal heat-generating body of current PTC heating device in the start-up of frequent work ~ heat-shut-down cooling and lead to the not hard up clearance between intraductal heating element and the conductive electrode and the insulating layer and the common jump fire between heating element and the electrode slice because of contact gap from this between the clearance of the heat stress release that leads to because of cold and hot shock in the twinkling of an eye in the cooling, carbonization and even cause the insulating layer to melt the surface electrification and the electric leakage that produce because of the local high temperature that leads to jumping fire for a long time, short circuit and puncture, the explosion, burn a series of great and malignant safety accidents such as inflammable plastic's indoor set.

The technical scheme is as follows: the utility model provides a PTC heating device's sub-assembly, includes PTC heating device, first installing support, second installing support, has connected temperature controller and temperature fuse's leading-in power pencil, first installing support has pedestal and closing cap, the electrified department cladding of the electrode slice leading-out end of different polarity and the coupling part of connecting power pencil has insulating cover, insulating cover with the electrified body surface of the coupling part of electrode slice leading-out end and connecting power pencil has all coated temperature resistant, insulating sealed glue.

Furthermore, the connection mode of the connection part is that the inserting spring riveted on the wire harness and the inserting sheet connected on the electrode sheet leading-out end are mutually inserted.

Further, the insulating sleeve is an insulating rubber sheath matched with the plug spring.

Further, the connection part is connected in a manner that the wire group is directly crimped on the leading end of the electrode sheet.

Further, the insulating sleeve is a temperature-resistant heat-shrinkable sleeve.

Furthermore, the second mounting bracket is embedded at the tail end of the heating device, and the tail part of the non-electrode leading-out end of the heating device is coated with temperature-resistant sealant to completely seal the gap at the tail end of the heating device.

Furthermore, the heat conduction aluminum pipe at the tail end of the heating device exceeds the tail end of the heating device by 0.5-10mm, a cavity for accommodating the exceeding part of the tail part of the heat conduction aluminum pipe is arranged on the bottom surface of the cavity of the second mounting support, and insulating sealant is filled in the cavity.

The prior art is as follows: (1) and no sealant is arranged in the cavity of the tail support, so that condensed water generated by cold and hot shock of the ambient temperature during the working of the heater easily permeates into the tail aluminum tube heating element to cause short circuit. (2) Linzhi CN302536477S, the afterbody has unsealed step, can't hold sealed glue. (3) The tail of the aluminum tube heating body is flush with the radiator or lower than the tail of the radiator. The utility model has the advantages that: (1) condensed water generated by cold and hot shock of the ambient temperature when the heater works can not permeate into the tail aluminum tube heating element to cause short circuit caused by water drops accumulated between the electrode plates inside or on the side surface of the heating element. (2) Make up the fit clearance between tail end heat-generating body and the radiator that leads to because of frock and human negligence in the device shaping solidification technology process, stop to cause the split glue between heat-generating body and the radiator from this, come unstuck, the bonding strength of assurance heater, assurance radiating effect and security and reliability. The safety and reliability of the heating device are improved.

Furthermore, the peripheral wall openings of the side wall of the cavity at the joint of the second mounting bracket and the heating device of the insert sleeve are provided with chamfers or grooves.

Furthermore, the chamfer or the groove inclines or sinks towards the inner side contacting the tail end of the heating device, and sealant for completely filling gaps at the joint of the peripheral wall openings of the side wall of the bracket and the heating device is poured in the chamfer or the groove.

The utility model has the advantages that: make up the fit clearance between tail end heat-generating body and the radiator that leads to because of frock and human negligence in the device shaping solidification technology process, stop to cause the split glue between heat-generating body and the radiator from this, come unstuck, the bonding strength of assurance heater, assurance radiating effect and security and reliability. The safety and reliability of the heating device are improved.

Furthermore, the combined part is provided with a first mounting bracket, a second mounting bracket and a power supply wiring harness connected with a temperature controller and a temperature fuse, the first mounting bracket is provided with a seat body and a sealing cover, and chamfers or grooves are arranged at peripheral wall openings of the side wall of the cavity at the joint of the seat body and the leading-out end of the heating device for accommodating and positioning.

Furthermore, the chamfer or the groove is sunken towards one side contacting the heating device, and sealant for completely filling gaps at the joint of the peripheral wall openings of the side wall of the support and the heating device is poured into the chamfer or the groove.

The prior art is as follows: lattice force CN 20101024587: (1) all power supply contacts are exposed on the surface of the bracket, the problem of electric leakage in sealing and use in a wet state cannot be solved, and the use is unsafe. (2) The joint of the bracket and the heater has no chamfer or groove, (3) the joint has no sealant, the gap of the joint is easy to seep water, the sealing performance can not be ensured, the problems of water seepage and electric leakage in the use in the moisture environment can not be solved, and the use is unsafe. Creativity of claims 27-29: the joint gap between the seat body of the bracket and the heating device has double sealing glue and strengthened sealing, and the chamfer or the groove of the joint surface can effectively store the sealing glue with better fluidity, thoroughly avoid water seepage and improve the waterproof performance. (3) The sealant stored at the chamfer increases the bonding area, improves the bonding strength, prolongs the service life, and avoids electric leakage and short circuit caused by moisture and condensed water drops.

Further, the assembly comprises a first mounting bracket, a second mounting bracket and a power supply wiring harness connected with a temperature controller and a temperature fuse, wherein the first mounting bracket comprises a base body and a sealing cover, and chamfers or grooves are arranged on the peripheries of all joint parts of the base body and the sealing cover.

Furthermore, the chamfer or the groove inclines or sinks towards one side of the cavity of the seat body, and sealant which coats all gaps at all joints of the seat body and the sealing cover is poured into the chamfer or the groove.

Further, after the seat body of the first mounting bracket is covered with the seal cover, a temperature-resistant and insulating heat-shrinkable sleeve is sleeved on the seat body, and the heat-shrinkable sleeve shrinks at the temperature of 70-120 ℃ to fix and seal the bracket into a closed whole without any fit clearance on the surface.

Further, the PTC heating devices are combined in parallel by a plurality of sets.

An electrical appliance contains a PTC heating device and assembly.

Further, the electric appliance is at least one selected from the group consisting of an air conditioner, a warm air blower, a hot air curtain machine, a bath heater, a dehumidifier, an air purifier, a clothes dryer, a new energy automobile heater and a defrosting demister.

Has the advantages that: compared with the prior art:

the sealing and insulating properties are greatly improved, reliable sealing and insulation of the electrified part are guaranteed, and overflow and waste of the sealing glue can be avoided. The operability and the process consistency of batch production are improved, and the production efficiency is greatly improved. Under the environment that the electric connection part and the power line leading-out terminal are totally immersed in water, the electrified part of the heating device and the surface thereof can still be ensured to be free from electric leakage. The problems of water seepage and electric leakage of the heater used in a humid environment are thoroughly solved, and the waterproof performance, the use safety and the use reliability are fundamentally solved.

The pencil closely compresses tightly and seals through the sealing washer, and sealed glue of sealed glue junction in addition thoroughly stops the hidden danger in tidal regime air and the water droplet infiltration pedestal cavity, even first support immerses in water, still can guarantee that the electrified tie point in first support cavity is sealed completely. The potential hazards of electric leakage and short circuit under the humid environment and the water immersion environment are solved structurally, and the safety and the reliability are greatly improved. The third through hole forms an embedded matching structure, so that the matching precision and the bonding strength are improved.

Condensed water generated by cold and hot shock of the ambient temperature when the heater works can not permeate into the tail aluminum tube heating element to cause short circuit caused by water drops accumulated between the electrode plates inside or on the side surface of the heating element. Make up the fit clearance between tail end heat-generating body and the radiator that leads to because of frock and human negligence in the device shaping solidification technology process, stop to cause the split glue between heat-generating body and the radiator from this, come unstuck, the bonding strength of assurance heater, assurance radiating effect and security and reliability. The safety and reliability of the heating device are improved.

Make up the fit clearance between tail end heat-generating body and the radiator that leads to because of frock and human negligence in the device shaping solidification technology process, stop to cause the split glue between heat-generating body and the radiator from this, come unstuck, the bonding strength of assurance heater, assurance radiating effect and security and reliability. The safety and reliability of the heating device are improved.

The joint gap between the seat body of the bracket and the heating device is provided with double sealants and enhances sealing, and the chamfer or the groove of the joint surface can effectively store the sealant with better fluidity, thereby thoroughly avoiding water seepage and improving the waterproof performance. The sealant stored at the chamfer increases the bonding area, improves the bonding strength, prolongs the service life, and avoids electric leakage and short circuit caused by moisture and condensed water drops.

Drawings

FIG. 1 is a schematic structural view of the insert of the present invention;

FIG. 2 is a cross-sectional view of the chamfer and glue applied at the joint of the cover plate and the first mounting bracket of the present invention;

FIG. 3 is a cross-sectional view of the first mounting bracket of the cover plate of the present invention pressing the sealant;

FIG. 4 is a schematic view of the first mounting bracket covering the cover plate and sleeving the heat shrink tube;

fig. 5 is a schematic structural diagram of the power harness of the present invention;

fig. 6 is a schematic structural diagram of the heating device of the present invention connected to a power supply harness;

fig. 7 is a schematic structural view of a second mounting bracket of the present invention;

fig. 8 is a schematic view of the plug spring of the present invention.

Detailed Description

The present invention will be further described with reference to the accompanying drawings and examples.

Example 1

A combined piece of a PTC heating device comprises the PTC heating device, a first mounting bracket, a second mounting bracket 16 and a lead-in power supply wiring harness connected with a temperature controller 17 and a temperature fuse 18, wherein the first mounting bracket is provided with a base body 19 and a sealing cover 20, the charged positions of the surfaces of electrode plate leading-out ends of different polarities and the connecting part of the connecting power supply wiring harness are coated with an insulating sleeve 37, and the insulating sleeve 37 and the charged surfaces of the electrode plate leading-out ends and the connecting part of the connecting power supply wiring harness are coated with temperature-resistant insulating sealing glue 14.

The connection of the connection part is realized by inserting the inserting spring 38 riveted on the wire harness and the inserting piece 39 connected with the leading-out end of the electrode piece 2.

The insulating sleeve 37 is an insulating rubber sheath that mates with the plug spring 38.

The connection mode of the connection part is that the wire group is directly pressed on the leading-out end of the electrode plate 2.

The insulating sleeve is a temperature-resistant heat-shrinkable sleeve.

The combined part is provided with a first mounting bracket, a second mounting bracket 16 and a power supply wiring harness connected with a temperature controller 17 and a temperature fuse 18, the first mounting bracket is provided with a seat body 19 and a sealing cover 20, and chamfers or grooves are arranged at the wall openings on the periphery of the side wall of the cavity at the junction of the seat body 19 and the leading-out end of the heating device for containing and positioning.

The chamfer or the groove is sunken towards one side contacting the heating device, and sealant 14 which completely fills gaps at the joint of the peripheral wall openings of the side wall of the support and the heating device is poured into the chamfer or the groove.

The assembly comprises a first mounting bracket, a second mounting bracket and a power supply wiring harness connected with a temperature controller 17 and a temperature fuse 18, wherein the first mounting bracket comprises a base 19 and a cover 20, and chamfers or grooves are arranged on the peripheries of all joint parts of the base 19 and the cover 20.

The chamfer or the groove inclines or sinks towards one side of the cavity of the seat body, and sealant which coats all gaps at all joints of the seat body and the sealing cover is poured into the chamfer or the groove.

In the assembly of the PTC heating device, after the seat body of the first mounting bracket is covered with the sealing cover, the heat-resistant and insulating heat-shrinkable tubing 25 is sleeved, and at the temperature of 70-120 ℃, the heat-shrinkable tubing 25 shrinks, so that the bracket is fixed and sealed into a closed whole without any fit clearance on the surface.

The PTC heating devices are combined in parallel.

Example 2

The utility model provides a PTC heating device's sub-assembly, includes PTC heating device, first installing support, second installing support 16, has connected temperature controller 17 and temperature fuse 18's power pencil, second installing support 16 inlays the cover and is in heating device's tail end, the tail portion of heating device's non-electrode leading-out end has coated temperature resistant sealed glue 14 will the space of heating device tail end is sealed completely.

The heat conduction aluminum pipe 1 at the tail end of the heating device exceeds the tail end of the heating device by 0.5-10mm, a cavity for accommodating the exceeding part of the tail part of the heat conduction aluminum pipe 1 is arranged on the bottom surface of the cavity of the second mounting bracket, and insulating sealant 14 is poured in the cavity.

And the peripheral wall openings of the side wall of the cavity at the joint of the second mounting bracket 16 and the heating device of the insert sleeve are provided with chamfers or grooves.

The chamfer or the groove inclines or sinks towards the inner side contacting the tail end of the heating device, and the sealant 14 which completely fills the gap at the joint of the peripheral wall opening of the side wall of the bracket and the heating device is poured in the chamfer or the groove.

The PTC heating devices are combined in parallel.

Example 3

An electrical appliance contains a PTC heating device and an assembly.

The electric appliance is at least one selected from an air conditioner, a warm air blower, a hot air curtain machine, a bath heater, a dehumidifier, an air purifier, a clothes dryer, a new energy automobile warm air device or a demisting and defrosting device.

Claims

1. A combination of PTC heating devices, characterized in that: the temperature-resistant and insulating sealing glue comprises a PTC heating device, a first mounting bracket, a second mounting bracket and a lead-in power supply wire harness connected with a temperature controller and a temperature fuse, wherein the first mounting bracket is provided with a base body and a sealing cover, the charged positions of the surfaces of the electrode plate leading-out ends of different polarities and the connecting part of the connecting power supply wire harness are coated with insulating sleeves, and the surfaces of the insulating sleeves and the charged bodies of the electrode plate leading-out ends and the connecting part of the connecting power supply wire harness are coated with temperature-resistant and insulating sealing glue.

2. An assembly of PTC heating devices according to claim 1, wherein: the connection mode of the connection part is that the inserting spring riveted on the wire harness and the inserting piece connected on the leading-out end of the electrode plate are mutually inserted.

3. An assembly of PTC heating devices according to claim 1 or 2, wherein: the insulating sleeve is an insulating rubber sheath matched with the inserting spring.

4. An assembly of PTC heating devices according to claim 1, wherein: the connection mode of the connection part is that the wire group is directly pressed on the leading-out end of the electrode plate.

5. An assembly of PTC heating devices according to claim 1 or 4, wherein: the insulating sleeve is a temperature-resistant heat-shrinkable sleeve.

6. An assembly of PTC heating devices according to claim 1, wherein: the second mounting bracket is embedded at the tail end of the heating device, and the tail part of the non-electrode leading-out end of the heating device is coated with temperature-resistant sealant to completely seal the gap at the tail end of the heating device.

7. An assembly of PTC heating devices according to claim 6, wherein: the heat conduction aluminum pipe at the tail end of the heating device exceeds the tail end of the heating device by 0.5-10mm, a cavity for accommodating the exceeding part of the tail part of the heat conduction aluminum pipe is arranged on the bottom surface of the cavity of the second mounting support, and insulating sealant is poured in the cavity.

8. An assembly of PTC heating devices according to claim 6 or 7, wherein: and chamfers or grooves are arranged at peripheral wall openings of the side wall of the cavity at the joint of the second mounting bracket and the heating device of the bushing.

9. An assembly of PTC heating devices according to claim 8, wherein: the chamfer or the groove inclines or is sunken towards the inner side contacting the tail end of the heating device, and sealant for completely filling gaps at the joint of the peripheral wall openings of the side wall of the support and the heating device is poured into the chamfer or the groove.

10. An assembly of PTC heating devices according to claim 1, 2, 4, 6, 7 or 9, wherein: the combined part is provided with a first mounting bracket, a second mounting bracket and a power supply wire harness connected with a temperature controller and a temperature fuse, wherein the first mounting bracket is provided with a base body and a sealing cover, and chamfers or grooves are arranged at wall openings on the periphery of the side wall of the cavity at the junction of the leading-out end of the heating device and the base body.

11. An assembly of PTC heating devices according to claim 10, wherein: the chamfer or the groove is sunken towards one side contacting the heating device, and sealant for completely filling gaps at the joint of the peripheral wall openings of the side wall of the support and the heating device is poured into the chamfer or the groove.

12. An assembly of PTC heating devices according to claim 1, 2, 4, 6, 7, 9 or 11, wherein: the combined part comprises a first mounting bracket, a second mounting bracket and a power supply wiring harness connected with a temperature controller and a temperature fuse, wherein the first mounting bracket comprises a base body and a sealing cover, and chamfers or grooves are arranged on the peripheries of all joint parts of the base body and the sealing cover.

13. An assembly of PTC heating devices according to claim 12, wherein: the chamfer or the groove inclines or sinks towards one side of the cavity of the seat body, and sealant which coats all gaps at all joints of the seat body and the sealing cover is poured into the chamfer or the groove.

14. An assembly of PTC heating devices according to claim 1, 2, 4, 6, 7, 9, 11 or 13, wherein: after the seat body of the first mounting support is covered with the seal cover, the seat body is sleeved with a temperature-resistant and insulating heat-shrinkable sleeve, and the heat-shrinkable sleeve shrinks at the temperature of 70-120 ℃ to fix and seal the support into a closed whole without any fit clearance on the surface.

15. An assembly of PTC heating devices according to claim 1, 2, 4, 6, 7, 9, 11 or 13, wherein: the PTC heating devices are combined in parallel.

16. An electrical appliance, characterized by: an assembly comprising a PTC heating device according to any of claims 1, 2, 4, 6, 7, 9, 11 or 13.

17. The electrical appliance according to claim 16, wherein the electrical appliance is at least one selected from the group consisting of an air conditioner, a fan heater, a hot air curtain, a bath heater, a dehumidifier, an air cleaner, a clothes dryer, a new energy automobile heater, and a defogger.