A cage-type magnetic shielding electromagnetic induction heating device

Abstract

A cage-type magnetic shielding electromagnetic induction heating device comprises: a heat insulation member and a semi-alternating magnetic field source; wherein the semi-alternating magnetic field source comprises: an alternating magnetic field generating unit and a frame; the alternating magnetic field generating unit is composed of an E-shaped magnetic core and a coil arranged on the E-shaped magnetic core. The invention adopts an electromagnetic induction heating method, and compared with the currently used electric heating coil, it saves at least 35% of electricity, is easy to install, improves thermal efficiency and thermal insulation effect, makes the working environment moderate and comfortable, has no electromagnetic pollution to the surrounding environment, and is green and environmentally friendly.

Description

Technical Field

[0001] The present invention relates to the technical field of heating fluid in conductor pipelines, heating plastic in metal barrels or heating and melting low-melting-point conductive materials, and in particular to a cage-type magnetic shielding electromagnetic induction heating device. Background Art

[0002] At present, in high-cold areas, field steel pipe oil pipelines, especially heavy oil transportation, are often blocked by freezing, although they are wrapped with an insulation layer outside the pipeline. In industries such as plastics, due to the requirements of injection molding or extrusion processes, plastic raw materials need to be heated from low temperature to a high temperature that meets the requirements of injection molding or extrusion processes within a limited length of the steel barrel to be ejected from the end nozzle. The commonly used technical methods now are to use heating resistor wire wrapping heating or ceramic infrared tube wrapping heating. These technologies and methods have more or less shortcomings, some of which have high energy consumption, some have safety hazards, some do not meet the process requirements for temperature control accuracy, and some cause a significant increase in ambient temperature and are not environmentally friendly. Of course, electromagnetic induction heating is also used now, but due to technical limitations, there are still electromagnetic leakages that affect the normal operation of equipment in the surrounding environment, or cause physical harm to people, or because of high costs, so there are few practical industrial applications. Summary of the invention

[0003] The present invention aims to provide a cage-type magnetic shielding electromagnetic induction heating device, comprising: a heat insulating member covering the outside of a metal barrel and a semi-alternating magnetic field source arranged outside the heat insulating member;

[0004] The semi-alternating magnetic field source includes: an alternating magnetic field generating unit for generating an alternating magnetic field by powering on and a frame for installing the alternating magnetic field generating unit; the alternating magnetic field generating unit is composed of an E-shaped magnetic core and a coil arranged on the E-shaped magnetic core.

[0005] In one of the embodiments, the alternating magnetic field generating unit is embedded inside the frame, and the alternating magnetic field generating unit is provided in multiple numbers and is evenly distributed in a 360-degree circumference in a radial shape.

[0006] In one embodiment, the E-shaped magnetic core includes: a center pole, side poles and a yoke; the coil is wound around the outer periphery of the center pole, and the coil is partially embedded between the center pole and the side pole and located on the inner side of the yoke.

[0007] In one embodiment, the coil is wound around the outer periphery of the center pole, partially embedded between the center pole and the side pole and located inside the yoke.

[0008] In one of the embodiments, the alternating magnetic field generating unit is provided with industrial frequency, medium frequency, high frequency and ultra-high frequency alternating power supplies, and the alternating magnetic field generating unit generates corresponding industrial frequency, medium frequency, high frequency and ultra-high frequency alternating magnetic field sources.

[0009] In one embodiment, the skeleton is a semi-annular cylindrical structure, and two semi-annular cylindrical structure skeletons constitute a full-ring closed skeleton; the alternating magnetic field generating unit is embedded in the inner side of the skeleton, and the alternating magnetic field generating unit is radially evenly distributed in a 360-degree circumference to form a cage-type magnetic shield.

[0010] In one of the embodiments, an assembly component for fixing the closed frame formed by two semi-annular columnar structure frames is also provided at the connection point thereof.

[0011] In one embodiment, the E-shaped magnetic core includes a center magnetic pole, a side magnetic pole and a magnetic yoke in one body, and the E-shaped magnetic core is made of a high-resistance and high-permeability material.

[0012] In one embodiment, the thermal insulation component includes: a thermal insulation layer wrapped around the outside of the metal barrel and a plate-shaped thermal insulation block arranged outside the thermal insulation layer. The plate-shaped thermal insulation block is arranged between adjacent E-shaped magnetic cores and on the inner side of the coil to more effectively protect the coil.

[0013] In one embodiment, the heating device is wrapped around the surface of the metal barrel of the injection molding machine or the extruder, and can replace the existing resistance wire heating or infrared tube heating to heat the plastic in the barrel; the heating device is wrapped around the metal pipeline for conveying fluid, and can heat the fluid material in the pipeline; the heating device is wrapped around the surface of the crucible, and can heat and melt the conductive material in the crucible.

[0014] The beneficial effects of the present invention are as follows:

[0015] The present invention adopts the heat source-free induction heating technology of industrial frequency, medium frequency, high frequency and ultra-high frequency according to the provided alternating power frequency; the medium and high frequency electromagnetic induction heating has fast speed, high efficiency, no high temperature in the environment, no leakage, and is the safest explosion-proof electric heating method; at the same time, because it adopts the frequency range specified by the State Environmental Protection Administration, it is harmless to the human body.

[0016] The present invention adopts industrial frequency, medium frequency, high frequency and ultra-high frequency electromagnetic induction heating methods according to the frequency of the alternating power supply provided. Two sets of frames fixedly connected by the assembly components cooperate with the semi-alternating magnetic field source embedded on the frame to wrap the surface of the metal barrel. In the alternating magnetic field, the metal barrel generates eddy currents and heats up, which is directly transmitted to the material to be heated in the barrel. The induction heating device itself does not generate heat, has good power saving effect and long service life. Compared with the currently used electric heating coil, it can save at least 40% of power.

[0017] The cage-type magnetic shielding electromagnetic induction heating device of the present invention has high active efficiency: if the present invention is used for heating materials in plastic pressure forming processing, a single induction heating device can replace the original 2-3 electric heating rings. The cage-type magnetic shielding electromagnetic induction heating device of the present invention has low use cost, saves electricity, and requires less maintenance.

[0018] The present invention adopts an inventive alternating magnetic field generating unit embedded in the inner side of the annular cylindrical structure frame, and the alternating magnetic field generating unit is evenly distributed radially over a 360-degree circumference to form a cage-type magnetic shield.

[0019] The cage-type magnetic shielding electromagnetic induction heating device of the present invention has no electromagnetic pollution to the surrounding environment, is environmentally friendly, and completely solves the problems of large magnetic leakage and environmental pollution in the existing induction heating technology and is highly efficient and energy-saving.

[0020] The cage-type magnetic shielding electromagnetic induction heating device of the present invention effectively solves the problems of high energy consumption, low efficiency, potential safety hazards, high ambient temperature, electromagnetic leakage affecting the normal operation of equipment in the surrounding environment, or causing physical harm to people, etc. in the prior art, and effectively reduces the manufacturing cost. It is highly efficient, energy-saving, low in use cost, less in maintenance, long in service life, moderate and comfortable in working environment temperature, very little in external electromagnetic leakage, no electromagnetic pollution to the surrounding environment, and environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0022] Figure 1 It is a schematic diagram of the cross-sectional structure of the present invention when it is working;

[0023] Figure 2 It is a schematic diagram of the specific arrangement of the assembly components and the heat insulation member of the present invention;

[0024] Figure 3 It is a schematic diagram of the cross section of a semi-alternating magnetic field source;

[0025] Figure 4 It is a half-section structure schematic diagram of the alternating magnetic field generating unit when it is working;

[0026] Figure 5 It is a schematic diagram of the structure of the alternating magnetic field generating unit;

[0027] Figure 6 It is a schematic diagram of the E-shaped magnetic core structure of the present invention;

[0028] Figure 7 It is a schematic diagram of the instantaneous working magnetic circuit distribution of the unit composed of the alternating magnetic field generating unit and the metal barrel of the present invention;

[0029] Figure 8 This is a schematic diagram of a specific configuration of a skeleton of one embodiment of the present invention. DETAILED DESCRIPTION

[0030] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, inside, outside, center...) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0031] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0033] Example 1

[0034] Reference Figure 1 and Figure 3 , a cage-type magnetic shielding electromagnetic induction heating device, comprising: a heat insulating member 20 disposed outside a metal barrel and a semi-alternating magnetic field source 1 disposed outside the heat insulating member 20;

[0035] The semi-alternating magnetic field source 1 comprises: an alternating magnetic field generating unit 11 for generating an alternating magnetic field by powering on and a frame 12 for mounting the alternating magnetic field generating unit 11 ; the alternating magnetic field generating unit 11 comprises an E-shaped magnetic core 111 and a coil 112 arranged on the E-shaped magnetic core 111 .

[0036] Preferably, the alternating magnetic field generating unit 11 is embedded in the inner side of the skeleton 12, and the alternating magnetic field generating unit 11 is provided with a plurality of cage-type magnetic shielding bodies which are evenly distributed radially in a 360-degree circle. An alternating current is provided to the alternating magnetic field generating unit 11, and eddy current is generated in the metal barrel to induction heat the metal barrel, thereby heating the material in the metal barrel.

[0037] Preferably, the present invention is also provided with a temperature control unit (not shown) which can realize precise control of the heating temperature of the material in the metal barrel.

[0038] Reference Figures 4 to 6Preferably, the alternating magnetic field generating unit 11 comprises: an E-shaped magnetic core 111 and a coil 112. The E-shaped magnetic core 111 integrates a center magnetic pole 111a, a side magnetic pole 111b and a magnetic yoke 111c.

[0039] The coil 112 is wound around the outer periphery of the middle magnetic pole 111 a , and the coil 112 is partially embedded between the middle magnetic pole 111 a and the side magnetic pole 111 b and is located inside the yoke 111 c .

[0040] The E-shaped magnetic core 111 is made of high-resistance and high-permeability material. The middle magnetic pole 111a and the side magnetic pole 111b are teeth protruding from the inner side of the magnetic yoke 111c.

[0041] The present invention matches the flux cross-section of the middle magnetic pole 111a, the side magnetic pole 111b and the magnetic yoke 111c of the E-shaped magnetic core 111, so that the magnetic flux passing through the middle magnetic pole 111a is shunted to the two side magnetic poles 111b through the magnetic yoke 111c and guided to the magnetic flux of the surface of the metal barrel is ideally balanced; the E-shaped magnetic core 111 is evenly distributed radially 360 degrees to surround the outer periphery of the metal barrel, forming a perfect cage-type magnetic shield, blocking the alternating magnetic field generated by the alternating magnetic field generating unit 11 from radiating to the external space to achieve ideal shielding. The environmental protection concept is realized. The magnetic efficiency is maximized to achieve ideal energy saving.

[0042] The present invention arranges a high-resistance and high-permeability E-shaped magnetic core 111 with uniform radiation distribution around the metal barrel, which becomes an effective barrier to prevent the alternating magnetic field from radiating to the non-working environment and leaking out, forming an excellent cage-type magnetic shield with very little eddy current heating loss.

[0043] Reference Figure 7 , an alternating power supply is provided to the alternating magnetic field generating unit 11, an alternating current flows through the coil 112, and an alternating magnetic field is generated in the middle magnetic pole 111a of the E-shaped magnetic core 111 due to electromagnetic induction. The magnetic flux of the alternating magnetic field passes from the middle magnetic pole 111a of the E-shaped magnetic core 111 through the air gap insulation 20 to the metal barrel layer (magnetic and conductive material), and then flows to both ends and then enters the two side magnetic poles 111b respectively through the air gap insulation layer 3, and then merges into the middle magnetic pole 111a through the magnetic yoke 111c, forming a butterfly-shaped two-strand magnetic closed loop.

[0044] The alternating magnetic field generates numerous small eddy currents in the metal barrel due to electromagnetic induction, causing the metal barrel to heat itself due to the induced eddy currents, and then the heat is conducted through the metal barrel to complete the heating of the liquid or solid non-conductive material in the barrel. When the metal barrel is heated, the electromagnetic induction heating device itself does not generate heat, so the electromagnetic heating efficiency is high and the energy saving is significant. In addition, in electromagnetic induction heating, by adding magnetic poles, for the same metal heated body, the same heat energy is obtained per unit time, and the required excitation electric power is reduced by about 25%, and the power loss of the electromagnetic coil 112 is reduced by about 90%. The alternating magnetic field generating unit 11 with the E-shaped magnetic core 111 of high resistance and high magnetic conductivity material as the core and the induction heating unit composed of it have very little eddy current heat loss.

[0045] Preferably, the alternating magnetic field generating unit 11 is provided with industrial frequency, medium frequency, high frequency and ultra-high frequency alternating power supplies, and the alternating magnetic field generating unit 11 generates corresponding industrial frequency, medium frequency, high frequency and ultra-high frequency alternating magnetic field sources. Since the E-shaped magnetic core 111 is made of high resistance and high permeability materials, the self-induced eddy current loss or hysteresis loss of the alternating magnetic field generating unit 11 is extremely small regardless of industrial frequency, medium frequency, high frequency or ultra-high frequency, that is, the cage-type magnetic shielding electromagnetic induction heating device of the present invention has extremely high electromagnetic thermal efficiency and extremely significant energy saving.

[0046] Combination Figure 2 The thermal insulation member 20 includes: a thermal insulation layer 3 wrapped around the outside of the metal barrel and a plate-shaped thermal insulation block 2 arranged outside the thermal insulation layer 3. The plate-shaped thermal insulation block 2 is arranged between adjacent E-shaped magnetic cores 111 and on the inner side of the coil 112 to more effectively protect the coil 112.

[0047] Preferably, the electromagnetic induction heating device is wrapped around the surface of the metal barrel of the injection molding machine or the extruder, which can replace the existing resistance wire heating or infrared tube heating to heat the plastic in the barrel; the heating device is wrapped around the metal pipeline for conveying fluid, which can heat the fluid material in the pipeline; the heating device is wrapped around the surface of the crucible, which can heat and melt the conductive material in the crucible.

[0048] Example 2

[0049] Reference Figure 1 Figure 2 and Figure 8 As shown, the difference from the above embodiment is that the skeleton 12 is a semi-annular cylindrical structure, and two semi-annular cylindrical structure skeletons 121 constitute a full-ring closed skeleton 12; the alternating magnetic field generating unit 11 is embedded in the inner side of the skeleton 12, and the alternating magnetic field generating unit 11 is radially evenly distributed in a 360-degree circumference to form a cage-type magnetic shield.

[0050] An assembly component 30 for fixing the closed frame 12 formed by two semi-annular cylindrical structural frames 121 is also provided at the connection point thereof. The assembly component 30 may be a structure for fixing and assembling any separately arranged components, such as a nut with a screw and / or a flange.

[0051] More preferably, the assembly component 30 is composed of a hinge 4 and a latch 5, wherein the hinge 4 is arranged at one of the connection points of the closed frame 12 formed by two semi-circular cylindrical structural frames 121, and the latch 5 is arranged at the other connection point of the closed frame 12 formed by two semi-circular cylindrical structural frames 121. The hinge 4 connects the electromagnetic induction heating device composed of two groups of the semi-alternating magnetic field sources 1 and is fastened by the latch 5. The installation steps are simplified by providing the hinge 4 and the latch 5, so that the installation and maintenance process is simplified.

[0052] The hinge 4 connects the two groups of semi-alternating magnetic field sources 1 to form an electromagnetic induction heating device; the heat insulation layer 3 wraps the metal barrel, the induction heating unit embraces the heat insulation layer 3, and the electromagnetic induction heating device surrounds the metal barrel.

[0053] Since the present invention adopts two groups of semi-alternating magnetic field sources 1 connected by hinges 4 to form an electromagnetic induction heating device, it is easy to install, and an insulating layer 3 is added between the pipeline and the heating unit, which better improves the thermal efficiency and thermal insulation effect, making the working environment temperature moderate and comfortable.

[0054] Combination Figure 6 As shown, when working, any two adjacent poles (side magnetic pole 111b and side magnetic pole 111b, side magnetic pole 111b and middle magnetic pole 111a, middle magnetic pole 111a and middle magnetic pole 111a) in the same electromagnetic induction heating device have different polarities, and the magnetic pole and magnetic yoke 111c's magnetic concentration makes the alternating magnetic field generated by the alternating magnetic field generating unit 11 be diverted through the magnetic yoke 111c, magnetic pole magnetic concentration guide, and high-density transmission to the metal barrel, and the internal magnetic circuit is extremely short and always unobstructed. Studies have shown that: in electromagnetic induction heating, adding high magnetic permeability magnetic core magnetic concentration, for the same metal heated body, to obtain the same heat energy per unit time, the required excitation electric power is reduced by about 25%, and at the same time, the power loss of the alternating magnetic field generating unit 11 is reduced by about 90%. Therefore, the cage-type magnetic shielding electromagnetic induction heating device of the present invention has high efficiency and extremely significant energy-saving effect.

[0055] According to a further extension of this embodiment, the closed skeleton 12 can also be arranged to be composed of a plurality of skeleton modules (not shown) connected by assembly components 30. The purpose of easy transportation and flexible installation can be achieved by simply setting the assembly components 30 between any adjacent skeleton modules as movable locking mechanisms.

[0056] Furthermore, the assembly components 30 used to connect the above-mentioned skeleton modules are all provided with movable locking mechanisms, which can flexibly adjust the size of the finally formed closed skeleton 12 according to the application scenario.

[0057] Therefore, the present invention can exert the best magnetic efficiency and thermal efficiency, and achieve the best energy-saving effect, that is, high efficiency and energy saving; it has precise heating depth and heating area, and the temperature is easy to control. The present invention adopts an electromagnetic induction heating device structure consisting of two semi-alternating magnetic field sources 1 connected by hinges 4, and the installation and maintenance are simpler and more convenient. When the metal barrel is heated, the electromagnetic induction heating device itself does not generate heat, and the plate-shaped insulation block 2 protects the coil 112 again. Therefore, the cage-type magnetic shielding electromagnetic induction heating device of the present invention has a longer service life.

[0058] The working principle of the present invention is as follows:

[0059] The present invention utilizes the electromagnetic induction principle and Joule's law to convert electrical energy into thermal energy. When an alternating current passes through the coil 112, an alternating magnetic field is generated due to electromagnetic induction. The alternating magnetic field in the coil 112 is guided by the central magnetic pole 111a of the E-shaped magnetic core 111 to pass through the thermal insulation layer 3 to the metal barrel layer (magnetic and conductive material), and countless small eddy currents are generated in the metal barrel. The metal barrel itself is heated by the induced high-frequency eddy currents, and then the heat is conducted through the metal barrel to complete the heating of the liquid or solid non-conductive material in the barrel.

[0060] The principles of the present invention are derived from the following basic understandings: current flowing through a conductor has a thermal effect; Joule's law; ferromagnetic materials have a thermal effect caused by hysteresis loss under alternating magnetic flux; air is a magnetic conductor and will not saturate; the static magnetic field B has no effect on the heated body; the magnetic conductivity of magnetic materials is far greater than that of air, thousands or even tens of thousands of times; magnetic materials can concentrate the magnetic flux generated in the coil 112 for conduction, or they can focus the conduction, thereby reducing the divergence of the magnetic field, increasing the energy density, reducing the influence of leakage magnetic flux, and producing magnetic shielding; with the help of magnetic materials, the magnetic induction intensity and magnetic intensity rate, that is, the magnetic efficiency, in the induction space can be improved.

[0061] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A cage-type magnetic shielding electromagnetic induction heating device, characterized in that: include: A heat insulating member covering the outside of the metal barrel and a semi-alternating magnetic field source arranged outside the heat insulating member; wherein the semi-alternating magnetic field source comprises: an alternating magnetic field generating unit for generating an alternating magnetic field by powering on and a frame for installing the alternating magnetic field generating unit; the alternating magnetic field generating unit is composed of an E-shaped magnetic core and a coil arranged on the E-shaped magnetic core; the E-shaped magnetic core comprises: a middle magnetic pole, a side magnetic pole and a magnetic yoke; the coil is wound around the periphery of the middle magnetic pole, and the coil is partially embedded in the middle magnetic pole and The side magnetic poles are located between the side magnetic poles and on the inner side of the magnetic yoke; the alternating magnetic field generating unit is provided with industrial frequency, medium frequency, high frequency and ultra-high frequency alternating power supplies, and the alternating magnetic field generating unit generates corresponding industrial frequency, medium frequency, high frequency and ultra-high frequency alternating magnetic field sources; the skeleton is a semi-annular cylindrical structure, and two semi-annular cylindrical structure skeletons constitute a full-ring closed skeleton; the alternating magnetic field generating unit is embedded on the inner side of the skeleton, and the alternating magnetic field generating unit is evenly distributed radially over a 360-degree circumference, forming a cage-type magnetic shielding electromagnetic induction heating device.

2. The cage-type magnetic shielding electromagnetic induction heating device according to claim 1, characterized in that: An assembly component for fixedly connecting the closed frame formed by the two semi-annular columnar structure frames is also provided at the connection point of the closed frame.

3. The cage-type magnetic shielding electromagnetic induction heating device according to claim 1, characterized in that: The E-shaped magnetic core includes a center magnetic pole, a side magnetic pole and a magnetic yoke in one body, and the E-shaped magnetic core is made of a high-resistance and high-permeability material.

4. The cage-type magnetic shielding electromagnetic induction heating device according to claim 1, characterized in that: The thermal insulation component includes: a thermal insulation layer covering the outside of the metal barrel and a plate-shaped thermal insulation block arranged outside the thermal insulation layer. The plate-shaped thermal insulation block is arranged between adjacent E-shaped magnetic cores and inside the coil to more effectively protect the coil.

5. According to claim 1, a cage-type magnetic shielding electromagnetic induction heating device, the heating device is wrapped around the surface of the metal barrel of an injection molding machine or an extruder to heat the plastic in the barrel; or the heating device is wrapped around the outside of a metal pipeline for conveying fluid to heat the fluid material in the pipeline; or the heating device is wrapped around the surface of a crucible to heat and melt the conductive material in the crucible.

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