Car bent tube heater

Abstract

The present invention discloses a vehicle-use curved tube heater. The vehicle-use curved tube heater comprises a sheath, a radiator embedded in the sheath, at least two electrode sheets installed in the sheath, a heater sandwiched between the electrode sheets, and a plug cover connected to the sheath; a mounting hole is provided on the radiator, and a mounting column extending from the sheath and passing through the mounting hole; one of the electrode sheets abuts against the radiator. The vehicle-use curved tube heater of the present invention can reduce the gap caused by different material expansion coefficients and improve the heat transfer efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of automobile crankcase ventilation, in particular to a crankcase heater for an automobile. Background Art

[0002] Crankcase ventilation heaters are automotive accessories that are installed on the engine of a motor vehicle and connect the crankcase to the intake manifold. Gasoline or diesel engines generate exhaust gases between the piston and cylinder in the crankcase due to combustion, which contain unburned substances and nitrogen oxides as well as water vapor. These exhaust gases and engine oil and other substances exist in the form of oil mist. Previously, the mixture of crankcase exhaust gases and engine oil was discharged directly into the environment through a pressure relief valve. If the crankcase is not ventilated, the pressure inside it will continue to increase during engine operation and may eventually cause the engine to break down. Since the exhaust gases discharged from the crankcase contain harmful components, especially nitrogen oxides, new exhaust gas regulations have been adopted in Europe for closed crankcase ventilation systems (Euro 3 to 6 standards published in September 2014). At temperatures below 4 degrees Celsius, the water contained in the crankcase exhaust gases (due to condensation of water vapor) will freeze, resulting in a certain degree of blockage in the crankcase ventilation system. Crankcase ventilation heater came into being to contribute to environmental protection, especially for diesel engines, its exhaust gas circulation control has become an important means to reduce nitrogen oxide emissions.

[0003] The functional principle of the crankcase heater is to convert electrical energy into thermal energy. The process is completed by the core part of the heater and a PTC thermistor is also required to heat the entire heater through heat transfer, especially the metal heat sink, which is then transported to the air intake port that needs to be heated to prevent ice and blockage at the intersection of the crankcase and the intake pipe.

[0004] There are two designs of heaters that utilize PTC heat sources to generate heat.

[0005] One is to use the elastic force of the conductive metal electrode sheet to press the PTC thermistor assembly onto the plastic surface, and then conduct the heat energy through the plastic to the metal tube, and use the smaller thermal resistance of the metal to evenly distribute the heat energy to the metal tube. The metal tube is in direct contact with the blowby gas of the crankcase, and the heat transfer direction is: PTC thermistor - electrode sheet - plastic layer - heat sink. This structure of the heater has poor thermal conductivity of plastic material, and the thermal resistance at the plastic during heat transfer is very large, causing heat to accumulate at the heat source. After long-term use, the electrode sheet will oxidize and corrode due to overheating, eventually leading to product failure; and the heating efficiency is low and the heating speed is slow.

[0006] The other is a "heating core assembly" composed of a PTC thermistor and an electrode sheet that directly contacts the radiator. There is a layer of plastic inside the radiator to isolate the cross-flow gas and prevent the cross-flow gas from corroding the PTC thermistor. The heat transfer direction is: PTC thermistor - electrode sheet - heat sink - plastic layer. The radiator and plastic shell of this structure are designed as one piece. Due to the difference in the expansion coefficient of the two materials, a tiny gap will be generated during the thermal expansion and contraction process, which will increase the thermal resistance and reduce the heat transfer efficiency. In severe cases, it will cause the plastic to crack and the cross-flow gas to corrode the PTC thermistor, eventually making the product fail. Summary of the invention

[0007] Based on this, it is necessary for the present invention to provide a vehicle curved tube heater that can reduce the gap caused by different material expansion coefficients and improve the heat transfer efficiency.

[0008] In order to achieve the purpose of the present invention, the present invention adopts the following technical solutions:

[0009] A vehicle bent tube heater comprises a sheath, a radiator embedded in the sheath, at least two electrode sheets installed in the sheath, a heater sandwiched between the electrode sheets, and a plug cover connected to the sheath; a mounting hole is provided on the radiator, and a mounting column extending from the sheath and passing through the mounting hole; one of the electrode sheets abuts against the radiator.

[0010] The above-mentioned automotive curved tube heater has a radiator mounting hole, and the sheath extends a mounting column through the mounting hole of the radiator, which greatly enhances the bonding strength between the radiator and the sheath, thereby minimizing the gap between the sheath and the radiator during thermal expansion and contraction caused by differences in material expansion coefficients, preventing an increase in thermal resistance, improving heat transfer efficiency, and maintaining the effective state of the product.

[0011] In some embodiments, the sheath is a plastic sheath, and the plastic sheath is combined with the heat sink by co-injection molding, so that the plastic sheath extends with a mounting column that passes through the mounting hole. The plastic sheath and the heat sink are co-injected to achieve the purpose of filling the heat sink with plastic, thereby minimizing the gap caused by thermal expansion and contraction caused by differences in material expansion coefficients.

[0012] In some of the embodiments, the heat sink is formed by machining.

[0013] In some embodiments, the number of the mounting holes is multiple. Multiple holes can ensure that the sleeve and the heat sink are more firmly connected.

[0014] In some embodiments, the mounting hole has a taper, and the taper hole can enhance the bonding strength between the heat sink and the sheath.

[0015] In some embodiments, the surface of the electrode sheet is provided with convex points, and the convex points abut against the heater. Providing convex points on the surface of the electrode sheet is conducive to reducing the contact area between the electrode sheet and the heat sink, the heater and the plug cover contact, thereby increasing the contact pressure of the electrical contact, improving the bonding force, reducing the contact resistance, and greatly increasing the service life of the entire heater under the condition of unchanged applied force.

[0016] In some embodiments, the electrode sheet is glued to the heater, and the glue can fill the plane contact parts, especially the tiny gaps, to greatly enhance the heat transfer performance.

[0017] In some embodiments, the electrode sheet is glued to the heat sink.

[0018] In some of the embodiments, the glued connection is made by silicone glue.

[0019] In some embodiments, the plug cover abuts against the electrode sheet.

[0020] In some embodiments, the electrode sheet is extended with a terminal, and the terminal is used to connect with a connector in the plug cover. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a schematic structural diagram of a vehicle curved tube heater according to an embodiment of the present invention;

[0022] Figure 2 Figure 1 A structural schematic diagram of the vehicle curved tube heater from another perspective;

[0023] Figure 3 Figure 1 A structural schematic diagram of the vehicle curved tube heater from another perspective;

[0024] Figure 4 Figure 3 AA section view in the figure;

[0025] Figure 5 Figure 1 A schematic structural diagram of the radiator of the vehicle bent tube heater;

[0026] Figure 6 Figure 1 A schematic structural diagram of the electrode sheet of the vehicle bent tube heater;

[0027] Figure 7 Figure 1 A circuit schematic diagram of the vehicle bent tube heater. DETAILED DESCRIPTION

[0028] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0030] Please refer to Figures 1 to 4 An embodiment of the present invention provides a vehicle-use curved tube heater 100, which is used to transfer heat to the air intake position that needs to be heated, and prevent ice and blockage at the intersection of the curved tube and the intake pipe. The vehicle-use curved tube heater 100 includes a sheath 10, a radiator 20 buried in the sheath 10, at least two electrode sheets 30 installed in the sheath 10, a heater 40 sandwiched between the electrode sheets 30, and a plug cover 50 connected to the sheath 10 and abutting against the electrode sheets 30. The plug cover 50 can be connected to a connector to turn on the power supply. The heater 40 generates heat under the action of voltage, and the heat is transferred to the radiator, and then transferred to the entire heater by the radiator, so that the surface temperature of the entire heater, especially the inner wall of the heater, is maintained at zero degrees Celsius, so that the condensed water inside the heater cannot freeze.

[0031] Please continue to refer to Figures 1 to 4 The sheath 10 is in a round cylindrical shape, matching the shape of the car's curved pipe and intake pipe. The sheath 10 is made of plastic material so that it can be injection molded in a mold. The installation method of the sheath 10, that is, the installation structure set on the sheath 10, can be selected according to different car bodies, such as snap-on installation, adhesive installation, etc. If the snap-on installation method is used, a corresponding snap-on structure needs to be set on the sheath 10. Please refer to Figure 4 The sheath 10 and the heat sink 20 are integrally co-injected, that is, a first annular cavity 12 is formed in the sheath 10, and the heat sink 20 is installed in the first cavity 12. The first cavity 12 has a plurality of mounting posts 13 that penetrate the first cavity 12 and are used to connect the heat sink 20. A second cavity 14 is also formed in the sheath 10, and the second cavity 14 is connected to the first cavity 12. The second cavity 14 is used to install the heating core assembly formed by the electrode sheet 30 and the heater 40.

[0032] Please refer to Figure 4 and Figure 5The shape of the radiator 20 matches the sheath 10 and is cylindrical. The radiator 20 is made of metal material to form a metal tube, such as an aluminum tube. The radiator 20 is formed by mechanical processing and spliced ​​after stamping to form a two-half docking structure.

[0033] The radiator 20 is provided with a plurality of mounting holes 21, that is, the side wall of the radiator is provided with a plurality of mounting holes 21, which are used to connect the sleeve 10 to ensure that it is integrated with the sleeve 10, strengthen the bonding force between the two, and reduce the gap between the two. Structurally, the sleeve 10 is extended with a mounting column 13 that passes through the mounting hole 21, thereby connecting the sleeve 10 and the radiator 20. In one embodiment, the sleeve 10 is made of plastic, and the sleeve 10 and the radiator 20 are injection molded in a mold so that the plastic fills the radiator, ensuring that there is a mounting column 15 in the mounting hole 21, and the two have better bonding force. The above-mentioned mounting holes 21 are evenly spaced to make the bonding force between the radiator 20 and the sleeve 10 more uniform. Multiple mounting holes 21 can ensure that the sleeve 10 and the radiator 20 are more firmly connected.

[0034] Please refer to Figure 5 Furthermore, the mounting hole 21 has a taper, that is, the mounting hole 21 is a tapered hole. The tapered hole can enhance the bonding strength between the radiator 20 and the sleeve 10 .

[0035] Please refer to Figure 4 The number of electrode sheets 30 can be multiple, such as two, three, four, five, etc., but at least one electrode sheet 30 is connected to each side of the heater 40, that is, the number of electrode sheets 30 is at least two. In one embodiment, the number of electrode sheets 30 is two. One electrode sheet 30 abuts against one side of the heat sink 20, and the other electrode sheet 30 abuts against the plug cover 50 to electrically connect the plug cover 50, so that the plug cover 50 can be energized through the electrode sheet 30 to the heater 40.

[0036] Please refer to Figure 2 and Figure 6 Furthermore, each electrode sheet 30 is extended with a terminal 31 , and the terminal 31 extends into the plug cover 50 to be connected with the connector in the plug cover 50 .

[0037] Please refer to Figure 6Furthermore, the surface of the electrode sheet 30 is provided with convex points 32, and the convex points 32 abut against the heater. The provision of the convex points 32 is conducive to reducing the contact area between the electrode sheet 30 and the contact points of the heat sink 20, the heater 40 and the plug cover 50, thereby increasing the contact pressure of the electrical contact, improving the bonding force, reducing the contact resistance, and greatly increasing the service life of the heater under the condition that the applied force remains unchanged. The number of the above-mentioned convex points 32 is multiple, and they are evenly distributed on the surface of the electrode sheet 30 in an array. The shape of the convex points 32 can be semicircular, spherical, rectangular, cube, etc., and any shape is not limited to achieve its function.

[0038] In one embodiment, the electrode sheet 30 is glued to the heat sink 20. During the gluing, the glue can fill the plane contact parts, especially the small gaps, greatly enhancing the heat transfer performance. Similarly, the electrode sheet 30 is glued to the heater. Silicone glue is preferably used in the above-mentioned gluing connection.

[0039] Please refer to Figure 4 The heater 40 is preferably a PTC thermistor, which is sandwiched between the electrode sheets 30 and abuts against the electrode sheets 30. The shape of the heater 40 is preferably a block to match the shape of the electrode sheets 30. After the heater 40 and the electrode sheets 30 are connected, a heating core assembly is formed, and the heating core assembly is installed in the second cavity 14 in the sheath 10.

[0040] Please refer to Figure 1 , Figure 2 and Figure 4 The plug cover 50 is welded with the sheath 10 to form a whole with the sheath 10. A connector mounting cavity is provided in the plug cover 50 for inserting the connector. A plurality of convex ribs 51 are provided in the plug cover 50, and the convex ribs 51 abut against the electrode sheet 30 so that the plug cover 50 is electrically connected to the electrode sheet 30. In one embodiment, the plug cover 50 has a connector.

[0041] The above-mentioned vehicle bent tube heater 100 is connected to the heater by the connector in the plug cover 50 through the vehicle power supply, so that the heater is energized, and the heater in the heater, that is, the PTC thermistor, generates heat under the action of the voltage, and the heat is transferred to the porous metal tube, that is, the radiator 20, and then transferred to the entire heater by the radiator 20, so that the surface temperature of the entire heater, especially the inner wall of the heater, is maintained above zero degrees Celsius, so that the condensed water inside the heater cannot freeze. The circuit principle is as follows Figure 7 .

[0042] The above-mentioned automotive curved tube heater has a radiator mounting hole, and the sheath extends a mounting column through the mounting hole of the radiator, which greatly enhances the bonding strength between the radiator and the sheath, thereby minimizing the gap between the sheath and the radiator during thermal expansion and contraction caused by differences in material expansion coefficients, preventing an increase in thermal resistance, improving heat transfer efficiency, and maintaining the effective state of the product.

[0043] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A vehicle bent tube heater, characterized in that: It includes a sheath, a radiator buried in the sheath, at least two electrode sheets installed in the sheath, a heater sandwiched between the electrode sheets, and a plug cover connected to the sheath; the radiator is provided with a mounting hole, and the sheath extends with a mounting column passing through the mounting hole; one of the electrode sheets abuts the radiator, and a plurality of protrusions are provided on the surface of the electrode sheet, and the plurality of protrusions abut the heater, and the electrode sheet is glued to the heater, and the electrode sheet is glued to the radiator.

2. The vehicle bent tube heater according to claim 1, characterized in that: The sheath is a plastic sheath, and the plastic sheath is combined with the heat sink by co-injection molding, so that the plastic sheath is extended with a mounting column that passes through the mounting hole.

3. The vehicle bent tube heater according to claim 1, characterized in that: The number of the mounting holes is multiple.

4. The vehicle bent tube heater according to any one of claims 1 to 3, characterized in that: The mounting hole has a taper.

5. The vehicle bent tube heater according to claim 1, characterized in that: The glued connection is made by using silicone glue.

6. The vehicle bent tube heater according to claim 1, characterized in that: The plug cover abuts against the electrode sheet.

7. The vehicle bent tube heater according to claim 1 or 6, characterized in that: The electrode sheet is extended with a terminal, and the terminal is used to be connected with a connector in the plug cover.

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