Efficient PTC electric heater

Abstract

An efficient PTC electric heater comprises a plurality of PTC heating ceramic chips, silica gel and heat dissipation strips, the PTC heating ceramic chips are bonded between the two heat dissipation strips through the silica gel, one end of each heat dissipation strip is provided with an electric connection structure used for being externally connected with a power source, and the efficient PTC electric heater has the advantages that the PTC heating ceramic chips are thin sheets, the thickness ranges from 1.5 mm to 2.15 mm, and on the premise that safety is guaranteed, the PTC heating ceramic chips are not prone to falling off, and the service life of the PTC heating ceramic chips is prolonged. The power density of the PTC heating ceramic chip is effectively improved; the width of the heat dissipation strips is narrower and ranges from 5mm to 8mm, and the temperature of the air outlet can be increased; due to the adoption of the thin PTC heating ceramic chip and the narrow heat dissipation strips, the power density of the whole PTC electric heater is high, and the temperature of an air outlet is effectively improved.

Description

Technical Field

[0001] The utility model relates to the technical field of electric heating, in particular to a high-efficiency PTC electric heater. Background Art

[0002] PTC electric heater is an electric heater based on semiconductor materials. Its working principle is to use the characteristics of PTC (positive temperature coefficient) materials for heating. It can generate heat by itself when powered on. It has the advantages of high thermal efficiency, high power, no open flame, and safety. It is an ideal material for heating devices.

[0003] The PTC electric heater is mainly composed of a PTC heating ceramic sheet and a heat dissipation strip bonded together to form a whole. After power is turned on, the PTC heating ceramic sheet heats up, and the heat is transferred to the heat dissipation strip, which then transfers the heat to the surrounding environment. The wind-type PTC electric heater is generally installed in a heating device with an air duct, and the heat of the PTC heater is quickly taken away by a certain amount of air. The thickness T of the PTC heating ceramic sheet generally used in the PTC electric heaters on the market is relatively large, generally 2.4mm~3mm. The heat in the middle of the PTC heating ceramic sheet cannot be effectively and quickly dissipated, making its power density relatively small. The width W of the heat dissipation strip is also relatively large, generally above 8mm. In this way, the power density of the entire PTC heater is relatively small, making the temperature of the air outlet relatively low. Utility Model Content

[0004] In order to solve the above problems, the utility model provides a high-efficiency PTC electric heater, which includes: a plurality of PTC heating ceramic sheets, silica gel, and a heat dissipation strip. The plurality of PTC heating ceramic sheets are bonded between two heat dissipation strips by silica gel. An electrical connection structure is provided at one end of the heat dissipation strip for external power supply. For safety and to improve the power density of the PTC ceramic heating sheet, the thickness of the PTC heating ceramic sheet is set to 1.5mm to 2.15mm, and the width of the heat dissipation strip is 5mm to 8mm.

[0005] Furthermore, the heat dissipation strip may be formed by welding a left conductor plate, a right conductor plate and heat dissipation fins.

[0006] Furthermore, in order to ensure the installation of the entire product, a mounting bracket structure is provided at the other end of the left conductor plate relative to the electrical connection structure.

[0007] Furthermore, in order to increase the heat dissipation area and improve the power of the PTC heater, the heat dissipation strip adopts a fin-shaped heat dissipation fin, which is formed by folding a plate, and the thickness of the heat dissipation fin is preferably 0.1mm to 0.3mm.

[0008] Furthermore, in order to improve the welding strength of heat dissipation, the left conductor plate, the right conductor plate and the heat dissipation fins are made of the same material, such as metal aluminum material or composite metal material with high electrical and thermal conductivity.

[0009] Furthermore, in order to prevent factors such as moisture from affecting the performance of the PTC heater, insulating silica gel is coated on the surrounding surfaces of the PTC heating ceramic sheet exposed to the air.

[0010] Compared with the prior art, the beneficial effects of the utility model are:

[0011] 1. The thickness of the PTC heating ceramic sheet is set to 1.5mm~2.15mm. Under the premise of meeting safety requirements, the heat in the middle of the PTC heating ceramic sheet can be quickly dissipated, thereby improving the power density of the PTC heating ceramic sheet. The width of the heat dissipation strip is 5mm~8mm. Due to its small size, the power density of the PTC heating ceramic sheet is increased, that is, the heat dissipated per unit area of ​​the heat dissipation strip is increased, thereby increasing the power density of the entire PTC heater and effectively increasing the temperature of the air outlet.

[0012] 2. A mounting bracket structure is provided at the other end of the heat dissipation strip relative to the electrical connection structure, which solves the problem of installing the PTC electric heater on the heating device.

[0013] 3. Insulating silicone is applied to the surrounding surfaces of the PTC heating ceramic sheet exposed to the air, which effectively prevents moisture and conductive pollutants from entering between the positive and negative conductors and causing sparks, and effectively improves the performance of the PTC heater. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate exemplary embodiments and features of the present application and, together with the description, serve to explain the principles of the present application.

[0015] Figure 1 This is an assembly diagram of a high-efficiency PTC electric heater.

[0016] Figure 2 A schematic diagram of the explosion effect of a high-efficiency PTC electric heater.

[0017] Figure 3 Schematic diagram of the heat sink explosion effect.

[0018] Description of the numbers in the figure:

[0019] 100—PTC heating ceramic sheet; 200—heat dissipation strip; 201—left conductor plate; 201A—electrical connection structure; 201B—mounting bracket structure; 202—heat dissipation fin; 203—right conductor plate; 301—silicone; 302—insulating silicone; DETAILED DESCRIPTION

[0020] The exemplary embodiments of the present application will be described in detail with reference to the accompanying drawings. The same reference numerals in the accompanying drawings represent elements with the same or similar functions. Although various aspects of the embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless otherwise specified.

[0021] Among them, it is necessary to understand that the terms "left", "right", "middle", "longitudinal", "lateral", "length", "width", "thickness" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention or simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0022] The word “exemplary” is used exclusively herein to mean “serving as an example, example, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments.

[0023] In addition, in order to better illustrate the present application, numerous specific details are given in the specific embodiments below. Those skilled in the art should understand that the present application can also be implemented without certain specific details. In some examples, methods, means, components and circuits well known to those skilled in the art are not described in detail in order to highlight the subject matter of the present application. The design is further described below in conjunction with the accompanying drawings of the structural description.

[0024] like Figure 1-3 As shown,

[0025] A high-efficiency PTC electric heater comprises: a plurality of PTC heating ceramic sheets (100), silica gel (301), and a heat dissipation strip (200); the plurality of PTC heating ceramic sheets (100) are bonded between two heat dissipation strips (200) via the silica gel (301); and an electrical connection structure (201A) is provided at one end of the heat dissipation strip (200) for connecting to an external power source.

[0026] like Figure 2 A highly efficient manufacturing process for a PTC electric heater: printing silica gel (301) on a plane (203) of a heat dissipation strip (200), then arranging a plurality of PTC heating ceramic sheets (100) in an orderly manner on a plane (203) with a heat conductive adhesive, and then covering the PTC heating ceramic sheet (100) with one side (203) of another heat dissipation strip (200) with the heat conductive adhesive, and after the two heat dissipation strips (200) clamp the PTC heating ceramic sheet (100), the heat dissipation strips are fixedly placed on a bench using a mounting bracket structure (201B) at the other end of the heat dissipation strips for cylinder compression and curing, and in order to speed up the curing time, electric heating and curing can be performed, and after curing, the product is subjected to a withstand voltage test.

[0027] Furthermore, for the sake of safety and compliance with safety regulations (GB 4706.1-2005 standard 29.1.4, the electrical gap between the surfaces of PTC electric heating elements can be reduced to 1 mm), and based on the characteristics of the PTC heating ceramic sheet (100) itself: the thinner the thickness, the greater the power density (the heat in the middle can be dissipated quickly), but the thinner the thickness, the easier it is to crush, and the thinner the thickness, the shorter the distance between the two conductors, and when the surface falls into the conductor contaminants, it is more likely to cause sparks between the two electrodes. At the same time, the characteristics of the pressure resistance of the PTC heating ceramic sheet (100) must also be taken into account: the thinner the thickness, the lower the pressure resistance, so after comprehensive consideration, the thickness T of the PTC heating ceramic sheet (100) is set to 1.5 mm to 2.15 mm.

[0028] Furthermore, in order to increase the amount of heat dissipated per unit area of ​​the heat dissipation strip, the width dimension W of the heat dissipation strip is 5 mm to 8 mm, which effectively increases the power density of the entire PTC heater and the temperature of the air outlet.

[0029] like Figure 3 , the manufacturing process of the heat dissipation strip (200) of the first embodiment: the left conductor plate (201), the heat dissipation fins (202) and the right conductor plate (203) are connected by welding to form a whole.

[0030] Furthermore, in order to ensure the installation of the entire product and the positioning of the tooling during the product production process, a mounting bracket structure (201B) is provided at the other end of the left conductor plate (201) relative to the electrical connection structure (201A).

[0031] Furthermore, in order to increase the heat dissipation area and improve the power of the PTC heater, the heat dissipation strip (200) adopts a fin-shaped heat dissipation fin (202). The heat dissipation fin (202) can be folded from a metal aluminum sheet or a metal composite material with good thermal and electrical conductivity. The thickness of the fin is preferably 0.1 mm to 0.3 mm.

[0032] Furthermore, in order to optimize the manufacturing process and improve the welding process of the fin conductive sheet, the left conductor plate (201), the right conductor plate (203) and the heat dissipation fin (202) are made of the same metal material, aluminum or a composite metal material.

[0033] Furthermore, in order to prevent factors such as moisture from affecting the performance of the PTC heater, insulating silica gel (302) is coated on the surrounding surfaces of the PTC heating ceramic sheet exposed to the air.

[0034] The embodiments of the present application have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or improvements to the technology in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A high-efficiency PTC electric heater, comprising: A plurality of PTC heating ceramic sheets (100), silica gel (301), and a heat dissipation strip (200), wherein the plurality of PTC heating ceramic sheets (100) are bonded between two heat dissipation strips (200) by silica gel (301), and an electrical connection structure (201A) is provided at one end of the heat dissipation strip (200) for connecting to an external power source, and the characteristics are: the thickness of the PTC heating ceramic sheet (100) is 1.5 mm to 2.15 mm, and the width of the heat dissipation strip is 5 mm to 8 mm.

2. The high-efficiency PTC electric heater according to claim 1, characterized in that: The heat dissipation strip (200) is formed by welding a left conductor plate (201), a right conductor plate (203) and heat dissipation fins (202).

3. The high-efficiency PTC electric heater according to claim 2, characterized in that: The other end of the left conductor plate (201) relative to the electrical connection structure (201A) is provided with a mounting bracket structure (201B).

4. The high-efficiency PTC electric heater according to claim 3, characterized in that: The heat dissipation fins (202) are made of a plate material, and the thickness of the plate is set to 0.1 mm to 0.3 mm.

5. The high-efficiency PTC electric heater according to claim 2, characterized in that: The left conductor plate (201), the right conductor plate (203) and the heat dissipation fins (202) are made of metal materials with electrical conductivity and high thermal conductivity.

6. A high-efficiency PTC electric heater according to any one of claims 1 to 5, characterized in that: The surrounding surfaces of the PTC heating ceramic sheet (100) exposed to the air are coated with insulating silica gel (302).

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