Light and thin PUR hot melt adhesive machine pressure plate

Abstract

The utility model relates to the field of electric heating equipment, and particularly discloses a light and thin PUR (Polyurethane) hot melt adhesive machine pressure plate which comprises an upper pressure plate, a lower pressure plate, an outer ring sealing ring, a gear pump and a plurality of heating rods, a net-shaped notch is formed in the lower surface of the lower pressing disc, and an inwards-sunken heating cavity is formed in the upper side of the lower pressing disc; a plurality of heat conduction ridges are arranged below the upper pressing disc, heating holes used for containing heating rods are formed in the heat conduction ridges, and the lower surfaces of the heat conduction ridges abut against the bottom face of the heating cavity. A gear pump inlet, a gear pump outlet and at least two glue outlet holes for outputting PUR hot melt glue are formed in the upper end of the upper pressure plate, an overflow valve is arranged between the gear pump outlet and the gear pump inlet, and an exhaust valve communicated with the gear pump inlet is arranged on the outer side of the upper pressure plate. Through the compact structural design of the upper pressure plate and the lower pressure plate, the overall height of the pressure plate is reduced, the pressure plate height is lower, the pressure plate weight is lighter, the heat loss of the pressure plate is reduced, and the heat conduction efficiency is improved.

Description

Technical Field

[0001] The utility model relates to the field of electric heating equipment, in particular to a light and thin PUR hot melt adhesive machine pressure plate. Background Art

[0002] PUR (Polyurethane Reactive) hot melt adhesive, the full name in Chinese is moisture-curing reactive polyurethane hot melt adhesive, with adjustable adhesion and toughness (elasticity), excellent bonding strength, temperature resistance, chemical corrosion resistance and aging resistance. It has become one of the important varieties in the adhesive industry. In the actual production and application of PUR hot melt adhesive, the platen-type PUR hot melt adhesive machine is the main heating pumping equipment. Its heating part is an aluminum alloy or steel platen. When in use, the platen is pressed into the glue barrel from top to bottom. The platen is located above the glue. When the platen is heated, only the upper layer of glue contacts the heating plate, so that it reaches the melting point and melts. The lower part of the glue barrel is not heated at this time. The amount required during production is melted as much as needed to avoid aging and deterioration of the glue due to long-term heating. The glue is isolated from the air during melting: there is an O-ring seal between the platen and the inner wall of the glue barrel, so that the molten liquid glue will not come into contact with the air, ensuring the use conditions of PUR.

[0003] As a key component of the PUR hot melt adhesive machine, the pressure plate has excellent thermal conductivity, durability and cost-effectiveness. It is mostly made of aluminum alloy or steel as raw materials and is formed by CNC precision processing.

[0004] However, most aluminum alloy pressure plates on the market have the problem of being too thick, long and complicated finishing, and high production costs; and the overly thick pressure plate structure leads to large heat loss and low heat conduction efficiency. Steel pressure plates have the problem of being heavy and having poor thermal conductivity. Utility Model Content

[0005] In order to overcome the problems of the existing pressure plate being heavy, high cost and complicated processing, the utility model provides a light and thin PUR hot melt adhesive machine pressure plate.

[0006] The technical solution adopted by the utility model is: a light and thin PUR hot melt adhesive machine pressure plate, including an upper pressure plate, a lower pressure plate, an outer ring sealing ring, a gear pump and a plurality of heating rods;

[0007] The lower surface of the lower platen is provided with a mesh-shaped notch, the middle part of the lower platen is provided with a first middle hole penetrating the upper and lower surfaces of the lower platen, the side of the lower platen is provided with an annular groove for embedding the outer ring sealing ring, and the upper side of the lower platen is provided with an inwardly recessed heating cavity;

[0008] The upper pressure plate is fixedly connected to the lower pressure plate, a plurality of heat-conducting ridges are arranged below the upper pressure plate, a heating hole for accommodating the heating rod is arranged in the heat-conducting ridges, and the lower surfaces of the plurality of heat-conducting ridges are in contact with the bottom surface of the heating chamber;

[0009] A second middle hole abutting against the first middle hole is provided in the middle of the upper pressure plate, and a flow channel sealing ring is provided between the first middle hole and the second middle hole;

[0010] The upper end of the upper platen is provided with a gear pump inlet, a gear pump outlet and at least two glue outlet holes for outputting PUR hot melt adhesive, an overflow valve is provided between the gear pump outlet and the gear pump inlet, and an exhaust valve connected to the gear pump inlet is provided on the outer side of the upper platen;

[0011] The inlet of the gear pump is connected to the second middle hole, and the interior of the upper pressure plate is provided with a hole for sequentially connecting the outlet of the gear pump, the overflow valve and the inlet of the gear pump. The first glue passage is used to connect the tooth The second passage between the wheel pump outlet and the glue outlet Glue channel;

[0012] The gear pump inlet is connected to the inlet of the gear pump, and the gear pump outlet is connected to the outlet of the gear pump.

[0013] Preferably, a circuit compartment is provided inside the upper pressure plate, a first through hole communicating with the heating chamber is provided on the lower side of the circuit compartment, and a thermal resistor is fixedly provided on the lower surface of the circuit compartment.

[0014] Preferably, a cover plate is provided on the upper side of the circuit compartment.

[0015] Preferably, the first glue passage and the second glue passage are formed by a plurality of mutually connected processed holes, and each of the processed holes is provided with a second internal thread for fixing the plug.

[0016] Preferably, at least two of the glue outlet holes are respectively provided with at least one glue-through joint and at least one plug; and a glue-through tube for outputting PUR hot-melt adhesive is fixedly provided on the glue-through joint.

[0017] Preferably, a first internal thread for fixing the plug and the glue-through joint is provided in the glue outlet hole.

[0018] Preferably, a plurality of inwardly recessed weight-reducing hollows are provided at a position of the lower pressure plate that is not in contact with the heat-conducting ridge.

[0019] Preferably, the mesh-shaped slots include a plurality of strip-shaped slots and a plurality of concentric annular slots radiating outward from the first middle hole.

[0020] Preferably, a plurality of screw holes are provided on the bottom surface of the heating chamber, and the upper pressure plate is fixedly connected to the screw holes by screws.

[0021] The beneficial effects of the utility model are:

[0022] (1) Through the compact structural design of the upper and lower platens, the overall height of the platen is reduced by using the heating cavity and the heat-conducting ridge. The lower platen height and lighter platen weight reduce the heat loss of the platen itself and improve the heat conduction efficiency;

[0023] (2) Through the design of the vent valve and the relief valve, the gas in the pressure plate can be discharged in time, and the pressure can be automatically released when the pressure is too high, so that the flow rate of hot melt adhesive output by the gear pump is more uniform. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The present invention will be further described below in conjunction with the accompanying drawings, wherein:

[0025] Figure 1 This is an exploded view of the structure of the first embodiment of the utility model without the gear pump;

[0026] Figure 2 This is a schematic diagram of the structure of the first embodiment of the utility model without a gear pump;

[0027] Figure 3 This is a planed surface view of the upper pressure plate of the second embodiment of the utility model;

[0028] Figure 4 It is an oblique view of the lower pressure plate of the second embodiment of the present utility model.

[0029] In the figure: 1. lower pressure plate; 101. notch; 102. first middle hole; 103. annular groove; 104. weight-reducing hollow; 2. outer ring sealing ring; 3. upper pressure plate; 301. second middle hole; 302. second glue passage; 303. thermal ridge; 304. glue outlet hole; 4. heating rod; 5. flow channel sealing ring; 6. plug; 7. glue joint; 8. cover plate; 9. exhaust valve; 10. gear pump inlet; 11. gear pump outlet; 12. thermal resistor; 13. overflow valve; 14. circuit compartment. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0031] See also Figure 1and Figure 2 , is the first embodiment of the utility model, and this embodiment specifically discloses a thin and light PUR hot melt adhesive machine pressure plate, including an upper pressure plate 3, a lower pressure plate 1, an outer ring sealing ring 2, a gear pump and a plurality of heating rods 4;

[0032] The lower platen 1 and the upper platen 3 of this embodiment are both die-cast into rough blanks by die-casting aluminum technology, and then processed and trimmed by CNC. The lower surface of the lower platen 1 is provided with a mesh-shaped notch 101, and the middle of the lower platen 1 is provided with a first middle hole 102 that passes through the upper and lower surfaces of the lower platen 1. The side of the lower platen 1 is provided with an annular groove 103 for embedding the outer ring sealing ring 2, and the upper side of the lower platen 1 is provided with an inwardly recessed heating chamber; the outer ring sealing ring 2 is sleeved on the annular groove 103. The setting of the heating chamber makes the bottom of the lower platen 1 thinner.

[0033] The upper pressure plate 3 and the lower pressure plate 1 are fixedly connected by means of screws, snaps or threaded connections. A plurality of heat-conducting ridges 303 are provided in the heating chamber between the upper pressure plate 3 and the lower pressure plate 1. The plurality of heat-conducting ridges 303 are integrally formed with the upper pressure plate 3. A heating hole for accommodating the heating rod 4 is provided in the heat-conducting ridges 303. The lower surfaces of the plurality of heat-conducting ridges 303 are all in contact with the bottom surface of the heating chamber, thereby transferring the heat of the heating rod 4 to the lower pressure plate 1.

[0034] A second middle hole 301 is provided in the middle of the upper pressure plate 3 to abut against the first middle hole 102, and a flow channel sealing ring 5 is provided between the first middle hole 102 and the second middle hole 301;

[0035] The upper end of the upper platen 3 is provided with a gear pump inlet 10, a gear pump outlet 11 and at least two glue outlet holes 304 for outputting PUR hot melt adhesive, a relief valve 13 is provided between the gear pump outlet 11 and the gear pump inlet 10, and an exhaust valve 9 connected to the gear pump inlet 10 is provided on the outer side of the upper platen 3;

[0036] The gear pump inlet 10 is connected to the second middle hole 301, and the upper pressure plate 3 is provided with a first glue passage for sequentially connecting the gear pump outlet 11, the overflow valve 13 and the gear pump inlet 10, and a second glue passage 302 for connecting the gear pump outlet 11 and the glue outlet hole 304;

[0037] The gear pump inlet 10 is connected to the inlet of the gear pump, and the gear pump outlet 11 is connected to the outlet of the gear pump, and a sealing ring can be arranged therebetween to enhance the sealing.

[0038] When in working state, the heating rod 4 is powered on to heat the platen to the indicated temperature, and the solid PUR glue attached to the lower end of the lower platen 1 is dissolved into a viscous liquid by heat, flows along the notch 101 to the first middle hole 102, and then flows to the gear pump inlet 10. The gear pump can pump the PUR glue to the gear pump outlet 11 at a constant rate. Under normal working conditions, the PUR glue flows from the gear pump outlet 11 to the glue outlet 304, and the platen work is completed. Through the design of the vent valve, the gas under and inside the platen can be discharged in time.

[0039] If the external switch valve of the joint is closed, the glue cannot go out. At this time, the internal liquid pressure increases until it exceeds the set pressure of the relief valve 13, and the relief valve 13 automatically opens, and the glue flows back to the gear pump inlet 10. The opened relief valve 13 prevents damage to the gear pump and the glue pipeline.

[0040] Through the compact structural design of the upper platen 3 and the lower platen 1, the overall height of the platen is reduced by utilizing the heating chamber and the heat-conducting ridge 303. The lower platen height and lighter platen weight reduce the heat loss of the platen itself and improve the heat conduction efficiency.

[0041] See also Figure 3 and Figure 4 , which is the second embodiment of the utility model. The difference between this embodiment and the first embodiment is that the upper platen 3 of this embodiment is provided with a circuit compartment 14, the lower side of the circuit compartment 14 is provided with a first through hole connected to the heating chamber, the lower surface of the circuit compartment 14 is fixed with a thermal resistor 12, the upper side of the circuit compartment 14 is provided with a cover plate 8, and the cover plate 8 is provided with a second through hole for passing the wire. The signal line of the thermal resistor 12 and the power wires of the plurality of heating rods 4 are concentrated in the circuit compartment 14 and then pass through the second through hole.

[0042] The thermal resistor 12 is used to detect the actual temperature of the heat-conducting ridge 303 or the lower pressure plate 1 in real time, thereby providing a reference parameter for the temperature control of the heating rod 4 .

[0043] The first glue passage and the second glue passage 302 of this embodiment are formed by a plurality of processing holes connected to each other, each processing hole is provided with a second internal thread for fixing the plug 6, and the outer end of each processing hole is fixed and sealed by the plug 6. It is convenient to perform drilling processing to form the first glue passage and the second glue passage 302 inside.

[0044] This embodiment is provided with two glue outlet holes 304, each of which is provided with a glue passing joint 7 and a plug 6; a glue passing tube for outputting PUR hot melt adhesive is fixedly provided on the glue passing joint 7. A first internal thread for fixing the plug 6 and the glue passing joint 7 is provided in the glue outlet hole 304. The two glue outlet holes 304 can be used alternately, which is convenient for adjusting the position of the glue passing tube, and when one of the glue outlet holes 304 has a problem, the glue passing joint 7 and the plug 6 can be replaced in time for continued use.

[0045] The lower platen 1 is provided with a plurality of inwardly recessed weight-reducing hollows 104 at the position where it does not contact the heat-conducting ridge 303. This can reduce the weight and material of the lower platen 1, reduce the absorption and retention of heat by the platen itself, and improve the heating and cooling speed. Through actual experimental tests, in the physical comparison test under the same heating power, the conventional product takes 20 minutes to heat up to 150 degrees, and the product of this design takes 14 minutes to heat up to 150 degrees, reducing the preheating time by 30%, speeding up and saving energy.

[0046] The mesh-shaped slots 101 of this embodiment include a plurality of strip-shaped slots and a plurality of concentric circular slots radiating outward from the first middle hole 102 .

[0047] A plurality of screw holes are arranged on the bottom surface of the heating chamber, and the upper pressing plate 3 is fixedly connected to the screw holes by screws.

[0048] The structure of the upper platen 3 and the lower platen 1 of the present embodiment is more conducive to the use of die-cast aluminum technology to first produce rough blanks and then perform fine processing, thereby reducing the workload of fine processing, improving production efficiency, reducing the overall weight of the platen, and reducing production costs.

[0049] The above specific embodiments further describe the purpose, technical solutions and beneficial effects of the utility model in detail. It should be understood that the above are only specific embodiments of the utility model and are not intended to limit the protection scope of the utility model. It is particularly pointed out that for those skilled in the art, any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model should be included in the protection scope of the utility model.

Claims

1. A thin and light PUR hot melt adhesive machine pressure plate, characterized in that: It comprises an upper pressure plate (3), a lower pressure plate (1), an outer ring seal (2), a gear pump and a plurality of heating rods (4); The lower surface of the lower platen (1) is provided with a mesh-shaped notch (101), the middle of the lower platen (1) is provided with a first middle hole (102) penetrating the upper and lower surfaces of the lower platen (1), the side of the lower platen (1) is provided with an annular groove (103) for embedding the outer ring sealing ring (2), and the upper side of the lower platen (1) is provided with an inwardly recessed heating cavity; The upper pressure plate (3) is fixedly connected to the lower pressure plate (1), a plurality of heat-conducting ridges (303) are provided below the upper pressure plate (3), a heating hole for accommodating the heating rod (4) is provided in the heat-conducting ridges (303), and the lower surfaces of the plurality of heat-conducting ridges (303) are in contact with the bottom surface of the heating chamber; A second middle hole (301) abutting against the first middle hole (102) is provided in the middle of the upper pressure plate (3), and a flow channel sealing ring (5) is provided between the first middle hole (102) and the second middle hole (301); The upper end of the upper platen (3) is provided with a gear pump inlet (10), a gear pump outlet (11) and at least two glue outlet holes (304) for outputting PUR hot melt adhesive, an overflow valve (13) is provided between the gear pump outlet (11) and the gear pump inlet (10), and an exhaust valve (9) connected to the gear pump inlet (10) is provided on the outer side of the upper platen (3); The gear pump inlet (10) is in communication with the second middle hole (301); the upper pressure plate (3) is provided with a first glue passage for sequentially connecting the gear pump outlet (11), the overflow valve (13) and the gear pump inlet (10); and a second glue passage (302) for connecting the gear pump outlet (11) and the glue outlet hole (304); The gear pump inlet (10) is connected to the inlet of the gear pump, and the gear pump outlet (11) is connected to the outlet of the gear pump.

2. A thin and light PUR hot melt adhesive machine pressure plate according to claim 1, characterized in that: A circuit compartment (14) is provided inside the upper pressure plate (3), a first through hole communicating with the heating chamber is provided on the lower side of the circuit compartment (14), and a thermal resistor (12) is fixedly provided on the lower surface of the circuit compartment (14).

3. A thin and light PUR hot melt adhesive machine pressure plate according to claim 2, characterized in that: A cover plate (8) is provided on the upper side of the circuit compartment (14).

4. A thin and light PUR hot melt adhesive machine pressure plate according to claim 1, characterized in that: The first glue passage and the second glue passage (302) are both formed by a plurality of machined holes connected to each other, and each of the machined holes is provided with a second internal thread for fixing the plug (6).

5. The thin and light PUR hot melt adhesive machine pressure plate according to claim 1, characterized in that: At least two of the glue outlet holes (304) are respectively provided with at least one glue passage joint (7) and at least one plug (6); a glue passage tube for outputting PUR hot melt adhesive is fixedly provided on the glue passage joint (7).

6. A thin and light PUR hot melt adhesive machine pressure plate according to claim 5, characterized in that: The glue outlet hole (304) is provided with a first internal thread for fixing the plug (6) and the glue-through joint (7).

7. A thin and light PUR hot melt adhesive machine pressure plate according to claim 1, characterized in that: A plurality of inwardly recessed weight-reducing hollows (104) are provided at positions of the lower pressure plate (1) that are not in contact with the heat-conducting ridge (303).

8. The thin and light PUR hot melt adhesive machine pressure plate according to claim 1, characterized in that: The mesh-shaped slots (101) include a plurality of strip-shaped slots and a plurality of concentric circular slots radiating outward from the first middle hole (102).

9. A thin and light PUR hot melt adhesive machine platen according to claim 1, characterized in that: A plurality of screw holes are arranged on the bottom surface of the heating chamber, and the upper pressure plate (3) is fixedly connected to the screw holes by means of screws.

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