CN113811031B

CN113811031B - PTC heater

Info

Publication number: CN113811031B
Application number: CN202110959929.7A
Authority: CN
Inventors: 曹黎霞
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-08-20
Filing date: 2021-08-20
Publication date: 2023-08-22
Anticipated expiration: 2041-08-20
Also published as: CN113811031A

Abstract

The utility model belongs to the technical field of PTC heating, and particularly relates to a PTC heater. Aiming at the defects that the number of the electrical connection parts of the existing parallel PTC heater is large and no suitable bracket exists, the utility model adopts the following technical scheme: the utility model provides a PTC heater, includes main part and support, and the main part includes metal radiator, PTC piece group that generates heat, riveting piece, thermal circuit breaker, and the adjacent metal radiator and the adjacent PTC piece group that generates heat between the metal radiator form the unit that generates heat, and the unit that generates heat is parallelly connected, is located adjacent two sets of two clamp plates in the PTC piece group outside are two liang of being connected as an organic wholely that generate heat, and the support includes frame and apron, forms thickness direction location structure and width direction location structure of main part in the frame, the apron has the altitude locating piece along the clamp plate of altitude direction butt PTC heater. According to the PTC heater, the main body is connected with the pressing plates, so that the number of electric connection positions is reduced; the bracket limits the body of the PTC heater in three dimensions of thickness, width and height.

Description

PTC heater

Technical Field

The utility model belongs to the technical field of PTC heating, and particularly relates to a PTC heater.

Background

The existing PTC heater (also called PTC heater) is mostly composed of a galvanized outer pressing plate, a stainless steel corrugated spring piece, a galvanized inner pressing plate, a PTC heating piece, a nickel-plated copper electrode terminal, a PPS high-temperature plastic electrode sheath and the like. The existing PTC heater adopts corrugated radiating fins, improves the radiating rate, combines the advantages of gluing and mechanical type, fully considers various thermal and electric phenomena of the PTC heating element during working, and has strong binding force, excellent heat conduction and radiating performance, high efficiency, safety and reliability. A great prominence of PTC heater is that the PTC heater can not fully dissipate heat when it stops running due to fan failure, and its power can be automatically and sharply reduced, and the surface temperature of the heater is maintained at about Curie temperature (generally about 250deg.C), so that the phenomenon of "reddening" of the surface of the heater such as electric heating tube is avoided.

In the application of the PTC heating sheet, when the wind speed is zero, the temperature of the heating body rises, and other parts of the equipment can be damaged greatly. Therefore, when the PTC heating sheet is used as the heating element, a high-temperature-resistant bracket is required to be installed, and a certain reasonable installation space is ensured, so that the PTC heating sheet has enough heat dissipation space. In addition, when the PTC heater is applied to an air conditioner or the like, it is also required to occupy as small space as possible.

A conventional PTC heater (including a heater main body and a bracket) has a structure shown in fig. 1: connection terminals are arranged between each group of PTC heating sheets for connecting a power supply, and the distance between the two connection terminals is the sum of the thickness of two metal heat sinks and the thickness of one PTCR, and is generally smaller than 20mm. However, the thermal circuit breaker is not smaller than 34mm in size. Therefore, the distance between the two connection terminals is insufficient to accommodate the thermal circuit breaker, which must be placed on the other side. Because the thermal circuit breaker is located the opposite side, needs to increase parts such as wire and connect the circuit of the PTCR heater with the remote thermal circuit breaker like this, leads to the structure complicacy, and the contact point of heavy current increases, increases the potential safety hazard.

Therefore, in the chinese patent publication No. CN213026581U, a connector, a thermal circuit breaker and a PTC heater are disclosed, and the thermal circuit breaker, the connector and the wires are provided at the same end, so that the number of electrical connection parts is reduced, and the structure is also compact.

However, the prior art does not provide PTC heaters having a small number of electrical connections when the heat generating units are connected in parallel. In addition, the PTC heater of the prior art has the rivet and the connector arranged in the same direction, resulting in a larger volume of the PTC heater.

In addition, for such PTC heaters (whether parallel, serial or series-parallel mixed) or other similar PTC heaters in which thermal breakers, connectors and wires are provided at the same end as disclosed in the foregoing utility model, no suitable bracket for the same has been found. In addition, the prior PTC heater has the defects of more parts, complex assembly and larger volume because each electrode terminal is insulated by a PPS high-temperature plastic electrode sheath.

Disclosure of Invention

Aiming at the defects that the number of the electrical connection parts of the traditional parallel PTC heater is large and no suitable bracket exists, the utility model provides the PTC heater which has at least one of the effects of simple structure, small volume, convenient assembly and the like.

In order to achieve the above purpose, the utility model adopts the following technical scheme: a PTC heater includes a heater main body and a bracket,

the main body includes:

the heating unit comprises a metal radiator and a PTC heating sheet group, wherein the metal radiator comprises a pressing plate and corrugated radiating sheets;

the connecting unit comprises a riveting piece, a connector and a thermal breaker;

the connecting units are positioned at the same end of the heating unit in the height direction;

two pressing plates positioned outside two adjacent PTC heating sheet groups are connected into a whole in pairs, and the connecting position of the two pressing plates is positioned at the other end of the thermal circuit breaker;

the bracket comprises:

the frame is provided with a first accommodating part and a second accommodating part in the height direction, the first accommodating part and the second accommodating part are communicated in the height direction, the first accommodating part is communicated in the thickness direction to form a first accommodating ring, a thickness direction positioning structure and a width direction positioning structure of a main body are formed in the first accommodating ring, the second accommodating part is provided with a second accommodating ring and a rear sealing plate, the heating unit is positioned in the first accommodating part, and the connecting unit is positioned in the second accommodating part;

the cover plate is arranged on the second containing part of the frame, covers the front end of the second containing part in the thickness direction, is provided with a lead-out hole for the lead to pass through, and is provided with a height positioning block which is abutted against the pressing plate of the PTC heater in the height direction.

According to the PTC heater, the main body is connected with the pressing plates to replace connection between the riveting piece and the wiring terminal, so that the number of electric connection positions is reduced; the bracket limits the main body of the PTC heater in three dimensions of thickness, width and height through two parts of the frame and the cover plate, so that the main body of the PTC heater is fixed with the bracket. The thickness direction positioning structure and the width direction positioning structure restrict the main body of the PTC heater. The height direction of the PTC heater refers to the arrangement direction of PTC heating sheets in the PTC heating sheet group.

As an improvement, two inner pressure plates positioned outside two adjacent PTC heating sheet groups are integrally formed.

As an improvement, two inner pressing plates positioned at the outer sides of two adjacent PTC heating sheet groups are integrally formed by bending.

As an improvement, the integrated into one piece interior pressure plate includes two parallel portions and connects two the perpendicular portion of parallel portion, perpendicular portion evagination is in other clamp plates and butt first accommodation portion for form the space of direction of height between the main part with the first accommodation portion of frame, thereby improve radiating efficiency.

As an improvement, two riveting sheets adjacent to the thermal circuit breaker are arranged at one end of the corresponding metal radiator, which is far away from the thermal circuit breaker along the thickness direction of the PTC heating sheet.

As an improvement, the caulking pieces are connected with the wire through a first connector, the first connector has a caulking portion connected with the caulking pieces and a crimping portion crimped with the wire, and the caulking portion of the first connector is perpendicular to the crimping portion.

As an improvement, the first connector is a single piece.

As an improvement, the riveting piece is connected with a wire, and the lead-out directions of all the wires are the same.

As an improvement, the thermal circuit breaker includes a breaker main body having a first electric connection post and a second electric connection post, a second connector having one end riveted with the rivet piece and the other end riveted with the first electric connection post, and a third connector having one end riveted with the second electric connection post and the other end compressed with the wire.

As an improvement, the second connector and the third connector are a single piece.

As an improvement, the PTC heating sheet sets are two, and the wires are two; or (b)

The PTC heating sheet sets are three sets, and the number of the wires is three; or (b)

The PTC heating sheet sets are four sets, and three wires are arranged.

As a refinement, the first receiving ring and the second receiving ring have overlapping portions. The lower end of the first accommodating ring is partially overlapped with the upper end of the second accommodating ring, so that the structure is compact.

As an improvement, the overlapping part extends upwards to form a separation block, the separation block is provided with a notch for a wire to pass through, and the notch supports the wire. The spacer insulates each electrode from the connector on each electrode.

As an improvement, the overlapping part is provided with a first communication groove for the connector of the PTC heater to enter and a second communication groove for the thermal breaker of the PTC heater to enter. Wherein, the first communicating groove is usually a plurality of, and the second communicating groove is usually a plurality of.

As an improvement, the second communication groove extends to form a supporting part for supporting the thermal circuit breaker of the PTC heater.

As an improvement, a rear positioning groove matched with the thermal circuit breaker of the PTC heater is formed at the second communication groove of the rear sealing plate, a front positioning groove is formed on the cover plate, and the front positioning groove and the rear positioning groove are in front-back butt joint with the thermal circuit breaker of the PTC heater.

As an improvement, the lower end of the cover plate extends to form the height positioning block, and the height positioning block is inserted between the overlapping part and the pressing plate of the PTC heater, or the upper end of the height positioning block abuts against the second accommodating ring.

As an improvement, the lower end of the cover plate extends downwards to be abutted against the thickness positioning block of the pressing plate of the PTC heater along the thickness direction.

As an improvement, rear ends of two side parts of the first accommodating ring extend to form rear positioning parts, front ends of the bottom of the first accommodating ring extend to form front positioning parts, and the rear positioning parts and the front positioning parts form the thickness direction positioning structure.

As an improvement, the two side parts of the first containing ring extend inwards to form left and right convex ribs, the left and right convex ribs form the width direction positioning structure, and the left and right convex ribs enable a gap in the width direction to be formed between the main body and the bracket, so that the heat dissipation efficiency is improved.

As an improvement, the bottom of the first accommodating ring extends upwards to form a rear positioning part, and the rear positioning part also extends forwards to form a buckle.

As an improvement, the frame is in clamping connection with the cover plate, a clamping block is formed by extending the outer side of the second accommodating part, a clamping groove is formed by extending the cover plate, and the clamping block is matched with the clamping groove.

As an improvement, the upper portion of the first accommodating portion extends forwards to form a guide block, and the guide block is matched with the leading-out hole of the cover plate so as to guide the cover plate when the cover plate is assembled to the frame, so that the assembly is convenient. At the same time, the guide blocks reduce the inflow of dust into the frame.

The PTC heater has the beneficial effects that: the main body is connected with the connecting terminal through the outer pressing plate or the inner pressing plate to replace the connection between the riveting piece and the connecting terminal, so that the number of electric connection positions is reduced; the bracket limits the main body of the PTC heater in three dimensions of thickness, width and height through two parts of the frame and the cover plate, so that the main body of the PTC heater is fixed with the bracket.

Drawings

Fig. 1 is a schematic view showing a structure of a conventional PTC heater.

Fig. 2 is a simplified schematic diagram of a conventional PTC heater.

Fig. 3 is a schematic structural view of a PTC heater according to a first embodiment of the present utility model.

Fig. 4 and 5 are exploded views of the PTC heater according to the first embodiment of the present utility model at various angles.

Fig. 6 is a schematic view of a PTC heater according to the first embodiment of the present utility model after hiding the cover plate.

Fig. 7 is a schematic structural view of a main body of a PTC heater according to the first embodiment of the present utility model.

Fig. 8 is a structural exploded view of a main body of a PTC heater according to the first embodiment of the present utility model.

Fig. 9 is a schematic structural view of an inner pressure plate of a body of a PTC heater according to the first embodiment of the present utility model.

Fig. 10 is a schematic structural view of a frame of a bracket of a PTC heater according to the first embodiment of the utility model.

Fig. 11 is a schematic structural view of a cover plate of a bracket of a PTC heater according to the first embodiment of the present utility model.

Fig. 12 is a schematic structural view of a PTC heater according to a second embodiment of the present utility model.

Fig. 13 and 14 are exploded views of the PTC heater according to the second embodiment of the present utility model at different angles.

In the figure, 01, body; 02. a bracket;

1. an outer pressure plate;

2. corrugated fins;

3. an inner pressure plate; 31. a parallel portion; 32. a vertical portion;

4. PTC heating sheet group;

5. riveting sheets;

6. a thermal circuit breaker; 61. a breaker main body; 62. a second connector; 63. a third connector;

7. a first connector;

8. a wire;

9. a frame; 91. a first accommodation portion; 911. a first receiving ring; 912. a rear positioning portion; 913. a front positioning part; 914. left and right convex ribs; 915. a buckle; 92. a second accommodating portion; 921. a second receiving ring; 922. a rear sealing plate; 923. a superposition section; 924. a spacer block; 925. a notch; 926. a first communication groove; 927. a second communication groove; 928. a support part; 929. a rear positioning groove; 930. a clamping block; 931. a guide block;

10. a cover plate; 101. a lead-out hole; 102. a height positioning block; 103. a thickness positioning block; 104. a clamping groove; 105. a front positioning groove; 106. and a supporting block.

Detailed Description

The technical solutions of the inventive embodiments of the present utility model will be explained and illustrated below with reference to the drawings of the inventive embodiments of the present utility model, but the following embodiments are only preferred embodiments of the inventive embodiments of the present utility model, not all. Based on the examples in the implementation manner, other examples obtained by a person skilled in the art without making any inventive effort fall within the scope of protection created by the present utility model.

Referring to fig. 3 to 14, a PTC heater of the present utility model includes a heater main body and a bracket,

the main body includes:

the bracket comprises:

According to the PTC heater, the main body is connected with the connecting terminal through the outer pressing plate or the inner pressing plate to replace the connection between the riveting piece and the connecting terminal, so that the number of electric connection positions is reduced; the bracket limits the main body of the PTC heater in three dimensions of thickness, width and height through two parts of the frame and the cover plate, so that the main body of the PTC heater is fixed with the bracket.

Example 1

Referring to fig. 3 to 11, a PTC heater according to a first embodiment of the present utility model includes a body and a bracket including:

a frame 9, wherein the frame 9 has a first accommodating portion 91 and a second accommodating portion 92 in a height direction, the first accommodating portion 91 and the second accommodating portion 92 are communicated in the height direction, the first accommodating portion 91 has a first accommodating ring 911, a thickness direction positioning structure and a width direction positioning structure are formed in the first accommodating ring 911, and the second accommodating portion 92 has a second accommodating ring 921 and a rear sealing plate 922;

the cover plate 10, the cover plate 10 is disposed on the second accommodating portion 92 of the frame 9, the cover plate 10 covers the front end of the second accommodating portion 92, the cover plate 10 is provided with a lead-out hole 101 through which the lead wire passes, and the cover plate 10 has a height positioning block 102 that abuts against the platen of the PTC heater along the height direction.

Referring to fig. 7 to 9, the body of the PTC heater of the present embodiment comprises:

a plurality of metal heat sinks including an outer platen 1, an inner platen 3, and corrugated fins 2 between the outer platen 1 and the inner platen 3;

at least two sets of PTC heating sheet group 4PTC, PTC heating sheet group 4PTC includes the parallelly connected PTC heating sheet of multi-disc, PTC heating sheet glues between adjacent metal radiator:

at least two riveting pieces 5, wherein the riveting pieces 5 are arranged on the metal radiator;

a thermal breaker 6, the thermal breaker 6 being connected to the rivet tab 5;

wherein, adjacent metal radiators and a plurality of PTC heating sheets connected in parallel between the adjacent metal radiators form heating units, three heating units are arranged, and the three heating units are connected in parallel;

wherein, two inner pressure plates 3 outside the PTC of two adjacent PTC heating sheet groups 4 are connected into a whole. The number of the integrated inner pressing plates 3 is one.

In other embodiments, the inner pressing plate 3 and the outer pressing plate 1 or the outer pressing plate 1 and the outer pressing plate 1 are connected into a whole.

In this embodiment, two inner pressing plates 3 located at the outer sides of the PTC of the adjacent two PTC heating sheet groups 4 are integrally formed.

In this embodiment, the two inner pressing plates 3 located at the outer sides of the PTC of the two adjacent PTC heating sheet groups 4 are integrally formed by bending, that is, the two heating units share the same plate. In other embodiments, the two inner pressure plates 3 may be integrally connected by welding or the like.

In this embodiment, all the riveting pieces 5 are located at the same end of the PTC heater in the length direction, and the thermal breaker 6 is disposed between two adjacent riveting pieces 5.

In this embodiment, two riveting pieces 5 adjacent to the thermal circuit breaker 6 are disposed at one end of the corresponding metal radiator, which is far away from the thermal circuit breaker 6 along the thickness direction of the PTC heating sheet.

In this embodiment, the rivet 5 is connected to the wire 8 through a first connector 7, and the first connector 7 has a rivet portion connected to the rivet 5 and a crimp portion crimped to the wire 8.

In this embodiment, the first connector 7 is a single piece, so as to reduce the number of electrical connections.

In this embodiment, the riveting piece 5 is connected with the wires 8, and all the wires 8 are led out in the same direction.

In this embodiment, the thermal breaker 6 includes a breaker main body 61, a second connector 62 and a third connector 63, the breaker main body 61 has a first electrical connection post and a second electrical connection post, one end of the second connector 62 is riveted with the riveting piece 5, the other end is riveted with the first electrical connection post, one end of the third connector 63 is riveted with the second electrical connection post, and the other end is pressed with the wire 8.

In this embodiment, the second connector 62 and the third connector 63 are formed as a single piece, thereby reducing the number of electrical connections.

In this embodiment, the PTC heating sheet set 4 has three PTC sets, and the wires 8 have three wires.

In this embodiment, the first accommodation ring 911 and the second accommodation ring 921 have overlapping portions 923. The lower end of the first accommodation ring 911 and the upper end of the second accommodation ring 921 overlap with each other, and the structure is compact.

In this embodiment, the overlapping portion 923 extends upward to form a spacer 924, and the spacer 924 is provided with a notch 925 through which the wire passes, and the notch 925 supports the wire. The spacer 924 insulates each electrode from the connector on each electrode.

In this embodiment, the overlapping portion 923 is provided with a first communication groove 926 into which the first connector and the second connector enter and a second communication groove 927 into which the thermal cut-out 6 enters. Three first communication grooves 926 and one second communication groove 927 are provided.

In this embodiment, the second communication groove 927 extends to form a support portion 928 for supporting the thermal breaker 6.

In this embodiment, a rear positioning groove 929 adapted to the thermal circuit breaker 6 is formed at the second communication groove 927 of the rear sealing plate 922, a front positioning groove 105 is formed on the cover plate 10, and the front positioning groove 105 and the rear positioning groove 929 abut against the thermal circuit breaker 6 front and back to fix the thermal circuit breaker 6.

In this embodiment, the lower end of the cover plate 10 extends to form the height positioning block 102, and the height positioning block 102 is inserted between the overlapping portion 923 and the pressing plate of the PTC heater. The height positioning blocks 102 are plural.

In other embodiments, the upper end of the height positioning block 102 may abut the second accommodating ring 921.

In this embodiment, the lower end of the cover plate 10 extends downward to abut against the thickness positioning block 103 of the pressure plate of the PTC heater in the thickness direction. The thickness positioning blocks 103 are plural.

In this embodiment, rear positioning portions 912 are formed by extending rear ends of both side portions of the first accommodating ring 911, front positioning portions 913 are formed by extending front ends of the bottom portion of the first accommodating ring 911, and the rear positioning portions 912 and the front positioning portions 913 form the thickness direction positioning structure. The rear positioning portion 912 is plural.

In this embodiment, the two side portions of the first accommodating ring 911 extend inward to form left and right ribs 914, and the left and right ribs 914 form the positioning structure in the width direction. The left and right ribs 914 have a plurality of ribs. The left and right ribs 914 also allow the body to be more easily placed into the frame 9.

In this embodiment, the bottom of the first accommodating ring 911 extends upward to form a rear positioning portion 912, and the rear positioning portion 912 also extends forward to form a buckle 915, where the buckle 915 is clamped between the vertical portion of the inner platen 3 and the outer platen 5 above the vertical portion. The upper portion of the catch 915 forms a guide surface.

In this embodiment, the frame 9 is clamped to the cover 10, the outer side of the second accommodating portion 92 extends to form a clamping block 930, the cover 10 extends to form a clamping groove 104, and the clamping block 930 is matched with the clamping groove 104. The two clamping blocks 930 are arranged, one is positioned on the right side of the second accommodating part 92, and the other is positioned on the upper side of the second accommodating part 92.

In this embodiment, the upper portion of the first receiving portion 91 extends forward to form a guide block 931, and the guide block 931 is matched with the lead hole 101 of the cover 10 to guide the cover 10 when the cover 10 is assembled to the frame 9, so as to facilitate assembly. At the same time, the guide block 931 reduces the inflow of dust into the frame 9.

In this embodiment, the frame 9 is integrally formed of an insulating material. The cover plate 10 is integrally formed of an insulating material.

The PTC heater of the first embodiment of the utility model has the beneficial effects that: the connection between the external pressing plate 1 or the internal pressing plate 3 replaces the connection between the riveting piece 5 and the wiring terminal, so that the number of electric connection positions is reduced; the thermal circuit breaker 6 and all the riveting pieces 5 are arranged at the same end of the PTC heater, so that the size of the PTC heater is reduced, a cross-connection line and a terminal are eliminated, and a live wire is shortened; the thermal circuit breaker 6 is arranged between the riveting sheets, so that the influence of the thermal circuit breaker on the air inlet and outlet is eliminated; all the wires are led out in the same direction, so that the assembly is convenient; the riveting part and the compression joint part of the connector are vertical, so that the volume is small; the body of the PTC heater is restricted in three dimensions of thickness, width and height by two parts of the frame 9 and the cover plate 10, thereby fixing the body of the PTC heater to the bracket; a spacer 924 is provided to insulate between the electrodes (rivet piece and connector); the thermal circuit breaker is supported and fixed, so that the gap between the thermal circuit breaker 6 and the pressing plate is ensured; the lead is easy to be routed; the frame 9 and the cover plate 10 are easy to assemble; the whole structure is compact and the volume is small; the first accommodation portion 91 of the frame 9 penetrates in the front-rear direction, and a gap in the width direction and the height direction is provided between the frame 9 and the main body, so that the heat dissipation efficiency is high.

Example two

The second embodiment is different from the first embodiment in the number of heat generating units.

Referring to fig. 12 to 14, in the present embodiment, four heat generating units are all connected in parallel, and four PTC heat generating sheet groups 4PTC are provided. The number of the integrated inner pressing plates 3 is two.

In the present embodiment, two latching blocks 930 on the second accommodation ring 921 of the second accommodation portion 92 are formed on both sides.

In the present embodiment, the structures of the frame 9 and the cover plate 10 are adaptively adjusted according to the number of heat generating units.

Other structures and effects of the present embodiment are the same as those of the first embodiment, and will not be described here.

While the utility model has been described in terms of specific embodiments, it will be appreciated by those skilled in the art that the utility model is not limited thereto but includes, but is not limited to, those shown in the drawings and described in the foregoing detailed description. Any modifications which do not depart from the functional and structural principles of the present utility model are intended to be included within the scope of the appended claims.

Claims

1. A PTC heater comprising a heater body (01) and a bracket (02), characterized in that:

the main body (01) includes:

the heating unit comprises a metal radiator and a PTC heating sheet group (2), wherein the metal radiator comprises a pressing plate and corrugated radiating sheets (2);

a connection unit comprising a rivet (5), a connector and a thermal breaker (6);

two pressing plates positioned outside two adjacent PTC heating sheet groups (4) are connected into a whole in pairs, and the joint of the two pressing plates is positioned at the other end of the thermal circuit breaker (6);

the bracket (02) comprises:

a frame (9), wherein the frame (9) is provided with a first accommodating part (91) and a second accommodating part (92) in the height direction, the first accommodating part (91) and the second accommodating part (92) are communicated in the height direction, the first accommodating part (91) is communicated in the thickness direction to form a first accommodating ring (911), a thickness direction positioning structure and a width direction positioning structure of a main body (01) are formed in the first accommodating ring (911), the second accommodating part (92) is provided with a second accommodating ring (921) and a rear sealing plate (922), the heating unit is positioned in the first accommodating part (91), and the connecting unit is positioned in the second accommodating part (92);

the cover plate (10), the cover plate (10) is arranged on the second accommodating part (92) of the frame (9), the cover plate (10) covers the front end of the second accommodating part (92) in the thickness direction, the cover plate (10) is provided with a lead-out hole (101) for the lead (8) to penetrate out, and the cover plate (10) is provided with a height positioning block (102) which is abutted to the pressing plate of the PTC heater in the height direction.

2. A PTC heater according to claim 1, wherein: at least two heating units are arranged, and all the heating units are connected in parallel; the thermal circuit breaker (6) is connected with one of the riveting sheets (5), and the thermal circuit breaker (6) is arranged between two adjacent riveting sheets (5).

3. A PTC heater according to claim 1, wherein: the pressing plates are divided into an outer pressing plate (1) and an inner pressing plate (3), and the two inner pressing plates (3) positioned on the outer sides of the two adjacent PTC heating sheet groups (4) are integrally formed.

4. A PTC heater according to claim 3, wherein: the inner pressure plate (3) formed integrally comprises two parallel parts (31) and a vertical part (32) connected with the two parallel parts (31), and the vertical part (32) protrudes outwards from the rest of the pressure plate and abuts against the first accommodating part (91), so that a gap in the height direction is formed between the main body (01) and the first accommodating part (91) of the frame (9).

5. A PTC heater according to claim 1, wherein: the first accommodating ring (911) and the second accommodating ring (921) are provided with overlapping portions (923), the overlapping portions (923) extend upwards to form isolation blocks (924), the isolation blocks (924) are provided with notches (925) for the wires (8) to pass through, and the notches (925) support the wires (8).

6. A PTC heater according to claim 5, wherein: the overlapping part (923) is provided with a first communication groove (926) for the connector of the PTC heater to enter and a second communication groove (927) for the thermal circuit breaker (6) to enter.

7. A PTC heater according to claim 6, wherein: a support portion (928) extending at the second communication groove (927) to form a thermal breaker for supporting the PTC heater; a rear positioning groove (929) matched with the thermal circuit breaker of the PTC heater is formed at a second communication groove (927) of the rear sealing plate (922), a front positioning groove (105) is formed on the cover plate (10), and the front positioning groove (105) and the rear positioning groove (929) are in front-back butt joint with the thermal circuit breaker of the PTC heater.

8. A PTC heater according to claim 6, wherein: the lower end of the cover plate (10) extends to form the height positioning block (102), the height positioning block (102) is inserted between the superposition part (923) and the pressing plate of the PTC heater, or the upper end of the height positioning block (102) is abutted against the second accommodating ring (921); the lower end of the cover plate (10) extends downwards to be abutted against a thickness positioning block (103) of the pressing plate of the PTC heater along the thickness direction.

9. A PTC heater according to claim 1, wherein: rear ends of two side parts of the first accommodating ring (911) extend to form rear positioning parts (912), front positioning parts (913) extend to form front positioning parts (913) at the front ends of the bottoms of the first accommodating ring (911), and the rear positioning parts (912) and the front positioning parts (913) form the thickness direction positioning structure; the two side parts of the first accommodating ring (911) extend inwards to form left and right ribs (914), and the left and right ribs (914) form the width direction positioning structure.

10. A PTC heater according to claim 1, wherein: the bottom of the first accommodating ring (911) extends upwards to form a rear positioning part (912), and the rear positioning part (912) also extends forwards to form a buckle (915); the frame (9) is clamped with the cover plate (10), a clamping block (930) is formed by extending the outer side of the second accommodating part (92), a clamping groove (104) is formed by extending the cover plate (10), and the clamping block (930) is matched with the clamping groove (104); the upper part of the first accommodating part (91) extends forwards to form a guide block (931), and the guide block (931) is matched with the leading-out hole (101) of the cover plate (10).