Electromagnetic heating plate and manufacturing method thereof

Abstract

The invention discloses an electromagnetic heating plate and a manufacturing method thereof, the electromagnetic heating plate comprises a steel plate, a heating wire and a binding post, the steel plate is provided with a plurality of uniformly distributed annular grooves and a wiring groove, and the joint of each annular groove and the wiring groove is provided with a lower wire groove extending to the bottom of the annular groove; the heating wire is embedded in the wiring groove and is wound in the annular grooves through the lower wire grooves. The binding posts are installed on the side face of the steel plate and connected with the two extending ends of the heating wire. The problems that electromagnetic heating is not uniform, winding occupies extra space, the coil is prone to being damaged, and extra protection and covering are needed can be solved.

Description

Technical Field

[0001] The present invention relates to the technical field of electromagnetic heating plates, and more particularly to an electromagnetic heating plate and a manufacturing method thereof. Background Art

[0002] At present, most heating plates generally add a heating medium outside or inside the working steel plate, and the heating medium makes the working steel plate reach the required temperature through heat conduction. Among them, the electromagnetic heating plate achieves heating by winding a whole surface coil inside.

[0003] However, existing electromagnetic heating plates have the following problems: 1) the heating coil requires additional winding space; 2) the coil is easily damaged, and the wound coil requires special protection or covering; 3) the heating points are concentrated after winding, and it is impossible to achieve uniform temperature of the heating plate.

[0004] Therefore, providing an electromagnetic heating plate and a method for manufacturing the same is an urgent problem to be solved by those skilled in the art.

[0005] invention

[0006] In view of this, the present invention provides an electromagnetic heating plate and a manufacturing method thereof to solve at least one of the above-mentioned technical problems.

[0007] In order to achieve the above object, the present invention adopts the following technical solution:

[0008] An electromagnetic heating plate comprises a steel plate and a heating wire, wherein the steel plate has a plurality of evenly distributed annular grooves and a wiring groove, and each of the annular grooves and the wiring grooves intersect at a position where the annular grooves intersect with the wiring grooves and have a lower wiring groove extending to the bottom of the annular groove; the heating wire is buried in the wiring grooves and is respectively wound in a plurality of the annular grooves through a plurality of the lower wiring grooves, and both ends of the heating wire extend out of the steel plate.

[0009] Furthermore, it also includes a terminal, which is installed on the steel plate and connected to the two extended ends of the heating wire.

[0010] Furthermore, it also includes a temperature measuring element, and the steel plate has a temperature measuring groove; the temperature measuring element is installed in the temperature measuring groove.

[0011] Furthermore, it also includes an electrical connector, which is installed on the steel plate and connected to the temperature measuring element by wiring.

[0012] Furthermore, it also includes a heat insulation board, which is laid and installed on one side of the steel plate to cover the heating wire and the temperature measuring element.

[0013] Furthermore, it also includes a shielding plate, which is covered and installed on the heat insulation board.

[0014] A method for manufacturing an electromagnetic heating plate as described above comprises the following steps:

[0015] 1) Drill multiple evenly distributed annular grooves on the steel plate, open a wiring groove connecting multiple annular grooves and extending to the outside of the steel plate on the steel plate, and open a lower wiring groove extending to the bottom of the annular groove at the intersection of each annular groove and the wiring groove; or divide the steel plate into zones, drill multiple evenly distributed annular grooves in each zone, open a wiring groove connecting multiple annular grooves and extending to the outside of the steel plate in each zone, and open a lower wiring groove extending to the bottom of the annular groove at the intersection of each annular groove and the wiring groove;

[0016] 2) Grind and clean the steel plate surface and the annular groove, wiring groove and lower wire groove;

[0017] 3) The heating wires are wound in multiple wiring troughs in sequence along the wiring troughs and the lower wiring troughs, and finally the extended ends of the heating wires are led out of the wiring troughs; when the steel plate is divided into zones, the multiple heating wires are wound in the annular grooves, lower wiring troughs and wiring troughs of the multiple zones respectively;

[0018] 4) Install the terminal blocks at the locations where the wiring trough extends out of the steel plate, and then connect the extended ends of the heating wires to the terminal blocks;

[0019] 5) Lay the heat insulation board on one side of the steel plate and cover the heating wire;

[0020] 6) Install the shielding plate cover on one side of the steel plate and cover it with the heat insulation board.

[0021] Furthermore, the specific process of step 2) is as follows: first, the iron filings on the surface of the steel plate and in the annular groove, the lower wire groove and the wiring groove are removed; then, the angles and burrs of the winding area and the steel plate holes are polished; finally, the polished iron filings are first adsorbed with a vacuum cleaner, then blown with an air gun, and then adsorbed with a vacuum cleaner until there is no residue in all areas.

[0022] Furthermore, in step 3), the steel plate is divided into a plurality of main heating zones and a plurality of side zones. Before the plurality of heating wires are respectively wound in the annular grooves, lower wire grooves and routing grooves of the plurality of zones, the lower wire length of each main heating zone and each side zone is calculated, and the plurality of heating wires are respectively wound onto a plurality of winding reels and wait for winding.

[0023] Furthermore, in step 3), the specific winding process of the heating wire is: the heating wire enters the first lower wire groove along the wiring groove, and then the heating wire is wound clockwise or counterclockwise in the annular groove. At this time, the heating wire starts clockwise or the heating wire starts counterclockwise. After winding multiple turns, the wire goes out along the wiring groove and enters the next lower wire groove. The heating wire continues to be wound clockwise or counterclockwise in the next annular groove, and so on. When the heating wire starts clockwise, the winding direction of the annular grooves in the same column is the same, and the routing directions of the annular grooves in adjacent columns are opposite. When the heating wire starts counterclockwise, the winding direction is changed when it reaches the last annular groove in each column.

[0024] Furthermore, in step 3), the resistance of the heating wire is measured multiple times using a megger when the heating wire is wound.

[0025] Furthermore, in step 1), multiple temperature measuring grooves are opened on the steel plate or two temperature measuring grooves are opened in each zone, so that in step 4), the platinum resistor is installed in the temperature measuring groove, and an electrical connector is installed on the side of the steel plate, and the platinum resistor wiring is connected to the electrical connector.

[0026] It can be seen that the present invention provides an electromagnetic heating plate and a manufacturing method thereof. Compared with the prior art, the present invention has the following beneficial effects:

[0027] 1) Space for heating wire winding is processed on the steel plate, eliminating the need for external heating wires to occupy space;

[0028] 2) The annular grooves are evenly arranged at a certain interval, and a heating wire is wound in each annular groove. The heating wires wound in multiple annular grooves form a group or a heating zone. The advantage of concentrated heating of the heating wires is first distributed as point ring heating, and then gathered into a surface to achieve uniform heating of the heating plate;

[0029] 3) The heating wire is buried and wound in the annular groove and the wiring groove. The steel plate protects the heating wire and no additional covering protection is required. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] 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 embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0031] Figure 1 The accompanying drawing is a schematic diagram of the three-dimensional structure of a small-sized electromagnetic heating plate provided by the present invention.

[0032] Figure 2 The accompanying drawing is a top view of a small-sized electromagnetic heating plate provided by the present invention;

[0033] Figure 3 The attached picture is Figure 2 Middle AA section;

[0034] Figure 4 The accompanying drawing is a schematic structural diagram of a small-size steel plate provided by the present invention;

[0035] Figure 5 The accompanying drawing is a schematic structural diagram of a small-sized electromagnetic heating plate provided by the present invention after the heating wire is wound;

[0036] Figure 6 The accompanying drawing is a schematic structural diagram of a large-sized electromagnetic heating plate provided by the present invention;

[0037] Figure 7 The accompanying drawing is a schematic structural diagram of the partitions of a large-sized electromagnetic heating plate provided by the present invention. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] like Figure 1-7 As shown, an embodiment of the present invention discloses an electromagnetic heating plate, including a steel plate 1 and a heating wire 2, wherein the steel plate 1 has a plurality of evenly distributed annular grooves 11 and a wiring groove 12, and each annular groove 11 has a lower wire groove 13 extending to the bottom of the annular groove 11 at the intersection of the wiring groove 12; the heating wire 2 is buried in the wiring groove 12, and is respectively wound in a plurality of annular grooves 11 through a plurality of lower wire grooves 13, and both ends of the heating wire 2 extend out of the steel plate 1, and are then connected to the heater. The present invention can solve the problems of uneven electromagnetic heating, extra space occupied by winding, easy damage of the coil, and the need for extra protection and covering.

[0040] In order to further optimize the technical solution of the present invention, it also includes a terminal, which is installed on the steel plate 1 and connected to the two extended ends of the heating wire 2.

[0041] In order to further optimize the technical solution of the present invention, a temperature measuring element is also included, and the steel plate 1 has a temperature measuring tank; the temperature measuring element is installed in the temperature measuring tank and can monitor the temperature of the heating plate in real time.

[0042] In order to further optimize the technical solution of the present invention, an electric connector is also included. The electric connector is installed on the steel plate 1 and is connected to the temperature measuring element.

[0043] In order to further optimize the technical solution of the present invention, it also includes a heat insulation board, which is laid and installed on one side of the steel plate 1 to cover the heating wire 2 and the temperature measuring element, thereby increasing the thermal insulation performance and making the temperature uniformity of the steel plate 1 better and the heating process more energy-saving.

[0044] In order to further optimize the technical solution of the present invention, it also includes a shielding plate, which is covered and installed on the thermal insulation board to shield electromagnetic waves, reduce interference, and fix and protect the thermal insulation board.

[0045] The embodiment of the present invention also discloses a method for manufacturing the electromagnetic heating plate as above, comprising the following steps:

[0046] 1) When the size of the steel plate 1 is small, a plurality of evenly distributed annular grooves 11 are drilled on the steel plate 1, and a wiring groove 12 connecting the plurality of annular grooves 11 and extending to the outside of the steel plate 1 is opened on the steel plate 1, the depth of the annular groove 11 is greater than the depth of the wiring groove 12, and a lower wiring groove 13 extending to the bottom of the annular groove 11 is opened at the intersection of each annular groove 11 and the wiring groove 12; When the size of the steel plate 1 is large, the steel plate 1 is divided into zones, and a plurality of evenly distributed annular grooves 11 are drilled in each zone, and a wiring groove 12 connecting the plurality of annular grooves 11 and extending to the outside of the steel plate 1 is opened in each zone, and the annular grooves The depth of 11 is greater than the depth of the wiring groove 12, and a lower wire groove 13 extending to the bottom of the annular groove 11 is provided at the intersection of each annular groove 11 and the wiring groove 12; in this embodiment, the steel plate 1 is divided into 13 heating zones, including 4 side zones and 9 main heating zones, with a total of 1204 annular grooves 11, and the drilling depth of the annular groove 11 is 20 mm. A magnetic drill is used with an annular drill bit (outer diameter Φ40, inner diameter Φ32) for drilling. When drilling, a positioning point can be drilled in advance, and the annular grooves 11 can be drilled one by one according to the position of the positioning point to ensure the accuracy requirements and ensure that the position is not offset and the depth is in place;

[0047] 2) Grind and clean the surface of the steel plate 1 and the annular groove 11, the wiring groove 12 and the lower wire groove 13 to avoid damaging the heating wire;

[0048] 3) The heating wire 2 is wound in the plurality of wiring grooves 12 in sequence along the wiring groove 12 and the lower wiring groove 13, and finally the extended end of the heating wire 2 is led out of the wiring groove 12; when the steel plate 1 is divided into zones, the plurality of heating wires 2 are respectively wound in the annular grooves 11, the lower wiring grooves 13 and the wiring grooves 12 of the plurality of zones;

[0049] 4) Install the terminal blocks at the position where the wiring trough 12 extends out of the steel plate 1, and then connect the extended end of the heating wire 2 to the terminal block. In this embodiment, the joint of the heating wire 2 is tinned when it is made, the terminal block is crimped, and a high-temperature heat shrink tube is used for insulation protection, and it is fastened and fixed on the sealable terminal block. Specifically, the heating wire 2 is cut off about 80mm-100mm outside the steel plate 1, and the protective skin 12mm is peeled off and tinned, and a φ6 high-temperature heat shrink tube is inserted to press the wire nose. The φ6 high-temperature heat shrink tube is 50mm long. The wire nose is connected to the through-wall terminal and fixed with an m6 flat head screw. A φ15 high-temperature heat shrink tube 40mm is used at the connection. The heating terminal block is fixed on the steel plate 1, and then a multimeter or a shaker is used to measure the continuity of the wire group;

[0050] 5) Lay the heat insulation board on one side of the steel plate 1 and cover the heating wire 2. In this embodiment, the heat insulation board uses 32 pieces of 1200*198mm, 16 pieces of 450*198mm, 4 pieces of 1200*176mm, and 2 pieces of 450*176mm;

[0051] 6) Install the shielding plate on one side of the steel plate 1 and cover the heat insulation plate. In this embodiment, 18 shielding plates with a size of 932.5*480*3 mm and 9 shielding plates with a size of 978*480*3 mm are used.

[0052] Specifically, step 2) the specific process: first, remove the iron filings on the surface of the steel plate 1 and in the annular groove 11, the lower wire groove 13 and the wiring groove 12; then grind the angles and burrs of the winding area and the steel plate channel, such as the angle between the annular groove 11 and the lower wire groove 13, the burrs of the annular groove 11 and the wiring groove 12, the heating wire outlet hole and the platinum resistance wire outlet hole, etc., so that there are no sharp angles and burrs after grinding; finally, the ground iron filings are first adsorbed with a vacuum cleaner, then blown with an air gun, and then adsorbed with a vacuum cleaner until there is no residue in all areas.

[0053] Specifically, in step 3), the steel plate 1 is divided into a plurality of main heating zones and a plurality of side zones. Before the plurality of heating wires 2 are respectively wound in the annular grooves 11, the lower wire grooves 13 and the routing grooves 12 of the plurality of zones, the lower wire lengths of each main heating zone and each side zone are calculated, and the plurality of heating wires are respectively wound onto a plurality of winding reels to wait for winding. In this embodiment, there are 48 annular grooves*2, 86 annular grooves*2 in the side zone, and 104 annular grooves*9 in the main zone. Each annular groove needs to be wound around 4 turns. The length of a single annular groove is 3.14×38×4+100=577.3mm, and 577.3×48=27710.4mm, 577.3×86=49647.8mm, and 577.3×104=60039.2mm, and the short side zone (the tenth side) is obtained by adding the reserved transition. There are two wires of 28.5m in the long side areas (the twelfth side area 1012 and the thirteenth side area 1013), two wires of 50.5m in the long side areas (the twelfth side area 1012 and the thirteenth side area 1013), six wires of 60.5m at both ends of the main areas (the first main area 101, the second main area 102, the third main area 103, the seventh main area 107, the eighth main area 108, and the ninth main area 109), and three wires of 65m in the middle of the main areas (the fourth main area 104, the fifth main area 105, and the sixth main area 106).

[0054] Specifically, in step 3), the specific winding process of the heating wire 2 is as follows: a wire head of more than 200 mm is reserved outside the edge of the steel plate 1, the heating wire 2 is led into the first lower wire groove 13 along the wiring groove 12, and then the heating wire 2 is wound clockwise or counterclockwise in the annular groove 11. At this time, the heating wire 2 starts clockwise or counterclockwise, and after winding for multiple turns, the wire is led out along the wiring groove 12 and enters the next lower wire groove 13, and the heating wire 2 is continued to be wound clockwise or counterclockwise in the next annular groove 11. By analogy, when the heating wire 2 starts clockwise, the annular grooves 11 in the same column have the same winding direction, and the annular grooves 11 in adjacent columns are arranged in the same direction. The routing direction is opposite. When the heating wire 2 starts counterclockwise, the winding direction is changed when it reaches the last annular groove 11 in each column. In this embodiment, the heating wire 2 of the fourth main zone 104, the sixth main zone 106, the seventh main zone 107, the eighth main zone 108 and the ninth main zone 109 starts clockwise and needs to be wound in the opposite direction when entering the next column. The heating wire 2 of the first main zone 101, the second main zone 102, the third main zone 103 and the fifth main zone 105 starts counterclockwise and changes to the opposite direction (clockwise) when it reaches the last annular groove 11 in this column, and then enters the second column and winds clockwise to the last annular groove 11 in this column and changes direction again.

[0055] Of course, after the last annular groove 11 in each column is wound, it cannot be wound four full turns into the next column. Considering that the height of the coil may be higher than the plane height of the heating plate when it is wound four and a half turns, the last annular groove 11 in the next column needs to be wound three and a half turns to ensure the uniform flatness of the surface of the heating plate.

[0056] Of course, when the annular groove 11 and the wiring groove 12 have the same depth, the lower wiring groove 13 may not be provided.

[0057] In order to further optimize the technical solution of the present invention, in step 3), the resistance of the heating wire 2 is measured multiple times using an megohmmeter when the heating wire 2 is wound, so as to avoid secondary rework after the winding is completed, and to ensure that the insulation performance of the heating wire 2 is reliable after the winding is completed. In this embodiment, the winding needs to be stopped when the resistance value is less than 10, and the leakage point (it may be that the wire skin is damaged, or it may be that a part in the groove is not polished clean or there is residue) is found. The winding can be continued after it is handled. Usually, the megohmmeter is used to measure after winding a section. The megohmmeter needs to be used 2-4 times during each winding process to reduce the failure rate.

[0058] Specifically, in step 1), multiple temperature measuring grooves are opened on the steel plate 1 or two temperature measuring grooves are opened in each zone, so that in step 4), the platinum resistor is installed in the temperature measuring groove, and an electrical connector is installed on the side of the steel plate 1, and the platinum resistor wiring is connected to the electrical connector. In this embodiment, each heating zone has two platinum resistors, one main and one standby, for a total of 26 platinum resistors. Each platinum resistor is coated with thermal conductive silicone grease and inserted into the temperature measuring hole, fixed with m4*10 screws, the platinum resistor wire is sleeved with a tube and passed through the steel plate 1, the platinum resistor wire is sleeved into a φ2 / φ3 high-temperature heat shrink tube 15mm, 12-core aviation plugs are welded with 4-way platinum resistors, 8-core aviation plugs are connected with two-way platinum resistors, welding is completed to fix the aviation plug components, and a multimeter is used to measure whether the resistance value of the platinum resistor is normal.

[0059] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0060] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An electromagnetic heating plate, characterized in that: It includes a steel plate and a heating wire, wherein the steel plate has a plurality of evenly distributed annular grooves and a wiring groove, and each of the annular grooves and the wiring grooves intersect with each other and have a lower wire groove extending to the bottom of the annular groove; the heating wire is buried in the wiring groove and is respectively wound in a plurality of the annular grooves through a plurality of the lower wire grooves; both ends of the heating wire extend out of the steel plate.

2. An electromagnetic heating plate according to claim 1, characterized in that: It also includes a terminal post, which is installed on the steel plate and connected to the two extended ends of the heating wire.

3. The electromagnetic heating plate according to claim 1, characterized in that: It also includes a temperature measuring element, and the steel plate has a temperature measuring groove; the temperature measuring element is installed in the temperature measuring groove.

4. The electromagnetic heating plate according to claim 3, characterized in that: It also includes an electrical connector, which is mounted on the steel plate and connected to the temperature measuring element.

5. The electromagnetic heating plate according to claim 3, characterized in that: It also includes a heat insulation board, which is laid and installed on one side of the steel plate to cover the heating wire and the temperature measuring element.

6. The electromagnetic heating plate according to claim 5, characterized in that: It also includes a shielding plate, which is covered and installed on the heat insulation board.

7. A method for manufacturing an electromagnetic heating plate according to any one of claims 1 to 6, characterized in that: The following steps are involved: 1) Drill a plurality of evenly distributed annular grooves on the steel plate, and open a wiring groove connecting the plurality of annular grooves and extending to the outside of the steel plate on the steel plate, and open a lower wiring groove extending to the bottom of the annular groove at the intersection of each annular groove and the wiring groove; or divide the steel plate into zones, drill a plurality of evenly distributed annular grooves in each zone, and open a wiring groove connecting the plurality of annular grooves and extending to the outside of the steel plate in each zone, the depth of the annular groove is greater than the depth of the wiring groove, and open a lower wiring groove extending to the bottom of the annular groove at the intersection of each annular groove and the wiring groove; 2) Grind and clean the steel plate surface and the annular groove, wiring groove and lower wire groove; 3) The heating wires are wound in a plurality of annular grooves along the wiring grooves and the lower wiring grooves in sequence, and finally the extended ends of the heating wires are led out of the wiring grooves; when the steel plate is divided into zones, the plurality of heating wires are wound in the annular grooves, the lower wiring grooves and the wiring grooves of the plurality of zones respectively; 4) Install the terminal blocks at the locations where the wiring trough extends out of the steel plate, and then connect the extended ends of the heating wires to the terminal blocks; 5) Lay the heat insulation board on one side of the steel plate and cover the heating wire; 6) Install the shielding plate cover on one side of the steel plate and cover it with the heat insulation board.

8. The manufacturing method according to claim 7, characterized in that: Step 2) Specific process: First, remove the iron filings on the surface of the steel plate and in the annular groove, lower wire groove and wiring groove; then grind the angles and burrs of the winding area and the steel plate holes; finally, absorb the ground iron filings with a vacuum cleaner, then blow them with an air gun, and then absorb them with a vacuum cleaner until there is no residue in all areas.

9. The manufacturing method according to claim 7, characterized in that: In step 3), the steel plate is divided into a plurality of main heating zones and a plurality of side zones. Before the plurality of heating wires are respectively wound in the annular grooves, lower wire grooves and routing grooves of the plurality of zones, the lower wire length of each main heating zone and each side zone is calculated, and the plurality of heating wires are respectively wound onto a plurality of winding reels and wait for winding.

10. The manufacturing method according to claim 9, characterized in that: In step 3), the specific winding process of the heating wire is as follows: the heating wire enters the first lower wire groove along the wiring groove, and then the heating wire is wound clockwise or counterclockwise in the annular groove. At this time, the heating wire starts clockwise or counterclockwise. After winding multiple turns, the wire goes out along the wiring groove and enters the next lower wire groove. The heating wire continues to be wound clockwise or counterclockwise in the next annular groove, and so on. When the heating wire starts clockwise, the annular grooves in the same column have the same winding direction, and the annular grooves in adjacent columns have opposite routing directions. When the heating wire starts counterclockwise, the winding direction is changed when it reaches the last annular groove in each column.

11. The manufacturing method according to claim 7, characterized in that: In step 3), the resistance of the heating wire is measured several times using an megger while the heating wire is being wound.

12. The manufacturing method according to claim 7, characterized in that: In step 1), a plurality of temperature measuring chambers are opened on the steel plate or two temperature measuring chambers are opened in each zone, so that in step 4), a platinum resistor is installed in the temperature measuring chamber, an electrical connector is installed on the steel plate, and the platinum resistor wiring is connected to the electrical connector.

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