Foaming device for EVA (Ethylene Vinyl Acetate) material
The RF heating of EVA materials is subjected to radio frequency heating by means of radio frequency heating foaming device, which solves the problems of energy consumption and uneven heating of high-temperature and high-pressure processes in the existing EVA foaming material preparation methods, and achieves a more efficient and economical foaming process.
Patent Information
- Application Number
- CN202421559019.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-03
- Publication Date
- 2025-04-25
- Estimated Expiration
- 2034-07-03
AI Technical Summary
The existing preparation methods of EVA foaming materials have high temperature or high pressure processes, which have a long time and high energy consumption, resulting in increased costs and uneven heating methods, which affect product performance.
The radio frequency heating foaming device is used to generate radio frequency through the radio frequency generator, and the radio frequency port emits radio frequency, and radio frequency heating is performed on the mold on the stower to achieve uniform heating and foaming of EVA materials.
The RF heating foaming method is achieved uniform heating, energy-saving, time-saving and environmentally friendly, and the production efficiency and economic benefits of EVA foaming materials are improved.
Smart Images
Figure CN222792593U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of foaming, in particular to a foaming device for EVA materials. Background Art
[0002] At present, EVA (ethylene-vinyl acetate copolymer) is a copolymer formed by the copolymerization of ethylene-vinyl acetate. Compared with polyethylene, EVA has reduced its high crystallinity and improved its flexibility, impact resistance, filler compatibility and heat sealing performance due to the introduction of vinyl acetate monomer in the molecular chain. Due to its low density, good physical properties and good weather resistance, it is widely used in the fields of foaming shoe materials, sports equipment, membrane materials, hot melt adhesives, etc. At present, the midsole materials of various brands of sports shoes in the world are mostly foaming materials made of EVA and its blends with resins and rubber.
[0003] Compression molding (flat foaming) is the most commonly used method for preparing EVA foam materials in the prior art. This method involves high temperature or high pressure processes, as well as heating and cooling cycles, which takes a long time and consumes more energy, resulting in increased costs; at the same time, the heating method involved in the process requires heat to be conducted from the mold to the material from the outside to the inside, which has the disadvantages of uneven heating and affecting the performance of the product, thereby reducing the economic benefits and commercial value of the EVA foam molding. Utility Model Content
[0004] In order to solve the above-mentioned deficiencies in the prior art, the utility model proposes a foaming device for EVA material.
[0005] In order to achieve the above technical effects, the utility model adopts the following scheme:
[0006] A foaming device for EVA material comprises a radio frequency room, a placement rack and a mould; at least one of the two opposite sides of the radio frequency room is provided with a feed channel, and a closed door is provided corresponding to the feed channel; the placement rack is arranged in the radio frequency room, and a plurality of moulds are placed on the placement rack; a plurality of radio frequency ports are arranged on the inner wall of the radio frequency room, and any radio frequency port is connected to a radio frequency generator arranged in the side wall of the radio frequency room.
[0007] The preferred technical solution is that the closed door opens and closes vertically, the RF room is provided with two slide rails respectively located on both sides of the feed channel, the slide rails are vertically arranged, the closed door has two slide grooves respectively matching the two slide rails, the closed door is vertically slidably installed on the slide rails through the slide grooves, and the RF room is provided with a vertical hydraulic cylinder for driving the closed door to move vertically.
[0008] A preferred technical solution is that a rotating turntable is installed at the bottom of the RF room, the placement rack is installed on the turntable, the center of the turntable is fixedly connected to a rotating shaft rotatably connected to the bottom of the RF room, the bottom of the RF room is protruding with a circle of annular convex edges, the lower end of the turntable is provided with an annular groove matching the annular convex edge, the turntable is clamped on the annular convex edge through the annular groove and rotates, the bottom of the RF room is provided with an interlayer, the lower end of the rotating shaft extends into the interlayer and a worm gear is fixedly installed therein, the interlayer can be horizontally provided with a worm meshing with the worm gear, the worm is rotatably installed in the interlayer, and one end of the worm is connected to a driving motor.
[0009] According to a preferred technical solution, the rack comprises four columns arranged in a rectangular array, and a plurality of spaced apart layer plates are vertically arranged between the four columns.
[0010] According to a preferred technical solution, the mold comprises a bottom groove with an upward opening and a cover plate covering the upper end of the bottom groove, wherein the cover plate is fastened to the bottom groove by bolts, and the interior of the bottom groove matches the shape to be foamed.
[0011] Compared with the prior art, the beneficial effects are:
[0012] The utility model has a simple structure and is easy to use. The radio frequency is generated by the radio frequency generator and then emitted from the radio frequency port to perform radio frequency heating on the mold on the placement rack, thereby performing radio frequency foaming on the foaming material in the mold. Compared with the traditional compression molding technology, the radio frequency heating foaming method of the utility model has the advantages of uniform heating, energy saving, time saving and environmental protection. By utilizing radio frequency heating, the inside and outside of the EVA masterbatch to be foamed are heated simultaneously, the heating power is evenly distributed, the EVA masterbatch to be foamed is heated evenly, the comprehensive heating effect is good, the time consumption is shorter, and the energy consumption is lower. When the temperature of the EVA masterbatch to be foamed reaches the decomposition temperature of the foaming agent, the EVA is prompted to foam, and the foaming is more uniform. Therefore, the radio frequency heating of the utility model can greatly improve the production efficiency and economic benefits of the EVA foaming material. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Figure 1 It is a schematic diagram of the structure of the utility model;
[0014] Figure 2 It is a cross-sectional schematic diagram of the utility model.
[0015] Figure numerals: 1. RF room; 2. Feed channel; 3. Closed door; 4. Slide rail; 5. Hydraulic cylinder; 6. RF port; 7. RF generator; 8. Turntable; 9. Annular ridge; 10. Column; 11. Shelf; 12. Bottom groove; 13. Cover plate; 14. Rotating shaft; 15. Worm gear; 16. Worm; 17. Driving motor; 18. Interlayer. DETAILED DESCRIPTION
[0016] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.
[0017] A foaming device for EVA material comprises a radio frequency room 1, a placement rack and a mold; a feed channel 2 is provided on at least one of the two opposite sides of the radio frequency room 1, and a closed door 3 is provided corresponding to the feed channel 2; the placement rack is arranged in the radio frequency room 1, and a plurality of molds are placed on the placement rack; a plurality of radio frequency ports 6 are provided on the inner wall of the radio frequency room 1, and any radio frequency port 6 is connected to a radio frequency generator 7 arranged in the side wall of the radio frequency room 1.
[0018] The material to be foamed is placed in the mold, and then a number of molds are placed on the placement rack as a whole, and the closed door 3 is closed. The radio frequency generated by the radio frequency generator 7 is emitted through the radio frequency port 6 to heat and foam the foaming material in the mold.
[0019] Compared with the traditional compression molding technology, the radio frequency heating foaming method of the utility model has the advantages of uniform heating, energy saving, time saving and environmental protection. By using radio frequency heating, the EVA masterbatch to be foamed is heated inside and outside at the same time, the heating power is evenly distributed, the EVA masterbatch to be foamed is heated evenly, the comprehensive heating effect is good, the time consumption is shorter, and the energy consumption is lower. When the temperature of the EVA masterbatch to be foamed reaches the decomposition temperature of the foaming agent, the EVA is foamed and the foaming is more uniform. Therefore, the radio frequency heating of the utility model can greatly improve the production efficiency and economic benefits of EVA foaming materials.
[0020] The preferred technical solution is that the closed door 3 opens and closes vertically, the RF room 1 is provided with two slide rails 4 respectively located on both sides of the feed channel 2, the slide rails 4 are vertically arranged, the closed door 3 has two slide grooves respectively matching the two slide rails 4, the closed door 3 is vertically slidably installed on the slide rails 4 through the slide grooves, and the RF room 1 is provided with a vertical hydraulic cylinder 5 for driving the closed door 3 to move vertically.
[0021] A preferred technical solution is that a rotating turntable 8 is installed at the bottom of the RF room 1, and the placement rack is installed on the turntable 8. The center of the turntable 8 is fixedly connected to a rotating shaft 14 rotatably connected to the bottom of the RF room 1. The bottom of the RF room 1 is protruding with a circle of annular flange 9, and the lower end of the turntable 8 is provided with an annular groove matching the annular flange 9. The turntable 8 is rotated on the annular flange 9 through the annular groove. An interlayer 18 is provided at the bottom of the RF room 1, and the lower end of the rotating shaft 14 extends into the interlayer 18 and is fixedly installed with a worm gear 15. The interlayer 18 can be horizontally provided with a worm 16 meshing with the worm gear 15. The worm 16 is rotatably installed in the interlayer 18, and one end of the worm 16 is connected to a drive motor 17.
[0022] Since the RF ports 6 in the RF room 1 are not evenly distributed around the placement rack, in order to ensure that the mold on the placement rack can be evenly contacted with the RF, the worm 16 is driven to rotate by a motor, and the worm 16 is engaged with the worm wheel 15 to drive the turntable 8 to rotate through the rotating shaft 14. The placement rack rotates in the RF room 1 with the turntable 8, so that the mold on the placement rack can fully contact with the RF.
[0023] According to a preferred technical solution, the placement rack includes four columns 10 distributed in a rectangular array, and a plurality of spaced apart layer plates 11 are vertically arranged between the four columns 10 .
[0024] The mold is placed on the layer plate 11.
[0025] According to a preferred technical solution, the mold includes a bottom groove 12 with an opening facing upward and a cover plate 13 covering the upper end of the bottom groove 12. The cover plate 13 is fastened to the bottom groove 12 by bolts, and the interior of the bottom groove 12 matches the shape to be foamed.
[0026] In the description of the present utility model, it should be understood that the terms "upper", "lower", "top", "bottom", "inside", "outside", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the utility model product is conventionally placed when in use, or are the orientations or positional relationships conventionally understood by those skilled in the art. They are only for the convenience of describing the present utility model and 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 should not be understood as a limitation on the present utility model.
[0027] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.
[0028] Based on the embodiments of the present utility model, all other embodiments obtained by ordinary technicians in the field without making any creative work shall fall within the scope of protection of the present utility model.
Claims
1. A foaming device for EVA material, characterized in that: The invention comprises a radio frequency room (1), a placement rack and a mould; at least one of the two opposite sides of the radio frequency room (1) is provided with a feed channel (2), and a closed door (3) is provided corresponding to the feed channel (2); the placement rack is arranged in the radio frequency room (1), and a plurality of moulds are placed on the placement rack; a plurality of radio frequency ports (6) are arranged on the inner wall of the radio frequency room (1), and any radio frequency port (6) is connected to a radio frequency generator (7) arranged in the side wall of the radio frequency room (1).
2. The foaming device of EVA material as claimed in claim 1, characterized in that: The closed door (3) opens and closes vertically. The radio frequency room (1) is provided with two slide rails (4) respectively located on both sides of the feed channel (2). The slide rails (4) are vertically arranged. The closed door (3) has two slide grooves respectively matched with the two slide rails (4). The closed door (3) is installed on the slide rails (4) through the slide grooves in a vertical sliding manner. The radio frequency room (1) is provided with a vertical hydraulic cylinder (5) for driving the closed door (3) to move vertically.
3. The foaming device of EVA material as claimed in claim 1, characterized in that: A rotating turntable (8) is installed at the bottom of the radio frequency room (1), and the placement rack is installed on the turntable (8). A rotating shaft (14) rotatably connected to the bottom of the radio frequency room (1) is fixedly connected at the center of the turntable (8). A circle of annular convex edges (9) are protruding from the bottom of the radio frequency room (1). An annular groove matching the annular convex edge (9) is opened at the lower end of the turntable (8). The turntable (8) is rotated by being clamped on the annular convex edge (9) through the annular groove. An interlayer (18) is provided at the bottom of the radio frequency room (1). The lower end of the rotating shaft (14) extends into the interlayer (18) and is fixedly installed with a worm gear (15). The interlayer (18) can be horizontally provided with a worm (16) meshing with the worm gear (15). The worm gear (16) is rotatably installed in the interlayer (18), and one end of the worm gear (16) is connected to a driving motor (17).
4. The foaming device of EVA material according to claim 1, characterized in that: The placement rack comprises four columns (10) distributed in a rectangular array, and a plurality of spaced layer boards (11) are vertically arranged between the four columns (10).
5. The foaming device of EVA material according to claim 1, characterized in that: The mold comprises a bottom groove (12) with an opening facing upward and a cover plate (13) covering the upper end of the bottom groove (12); the cover plate (13) is fastened to the bottom groove (12) by bolts; and the interior of the bottom groove (12) matches the shape required for foaming.