Dispensing process method suitable for dispensing medium-viscosity glue to dense cavity and removing bubbles

Abstract

The invention discloses a dispensing process method suitable for dispensing medium-viscosity glue into a dense cavity to remove bubbles. The dispensing process method comprises the following steps that firstly, glue is pre-dispensed in a part; then the core body is loaded into a part, glue at the bottom is extruded, a gap between the core body and the part is filled with the glue from bottom to top, and air in the gap is exhausted; then top dispensing is conducted, top glue is self-leveled and connected with bottom glue at the edge, and the phenomenon that air trapping is formed due to the fact that the top glue is directly filled downwards along peripheral gaps and extrudes air, and air bubbles exist on the top glue face due to the fact that the glue viscosity is high and trapped air cannot be directly discharged is avoided; and standing the dispensed product for several minutes, enabling the product to enter a UV furnace for preliminary curing after the glue flow is leveled, and further curing at room temperature. The magnetic component product dispensed by the dispensing and curing process is good in air tightness, smooth in dispensing surface, free of pits and bubbles, free of cracks between glue and the surface of the product, good in bonding force and good in product appearance, and the phenomenon of air leakage caused by stripping of the glue and the surface of the product in a working environment is avoided.

Description

Technical Field

[0001] The invention belongs to the field of automobile and medical equipment sealing assembly of sensor parts, and in particular relates to a glue dispensing process method suitable for dispensing medium-viscosity glue into a sealed cavity to remove bubbles. Background Art

[0002] Hard magnetic components have the characteristics of being suction parts and providing magnetic sources, and are widely used in the fields of automotive interiors, medical device sensors, etc. Since the installation method mostly adopts component assembly, glue adhesives are often used to fix and seal, and the appearance of the glue curing must be flat and free of bubbles. The commonly used methods of dispensing and removing bubbles are: heating the product to accelerate the formation and bursting of bubbles; vacuuming to make the bubbles formed during the dispensing process burst quickly; oscillation to accelerate the movement of bubbles to the surface and finally burst them.

[0003] However, for products with small dispensing volume, high glue quantity control precision, and medium to high glue viscosity, the above three process methods cannot achieve zero bubble operation.

[0004] To this end, the present invention proposes a glue dispensing process method suitable for dispensing medium-viscosity glue into a dense cavity to remove bubbles. Summary of the invention

[0005] In view of the problems existing in the prior art, the purpose of the present invention is to provide a dispensing process method suitable for dispensing medium viscosity glue into a sealed cavity to remove bubbles, so as to avoid the formation of bubbles after curing when using medium and high viscosity glue to fill the sealing component, thereby affecting the product appearance and customer experience.

[0006] To achieve the above object, the technical solution of the present invention is as follows: A dispensing process method suitable for dispensing medium-viscosity glue into a dense cavity to remove bubbles, specifically comprising the following steps: S1: Apply a proper amount of glue to the part cavity; S2: assemble core parts; S3: The core and the parts are closely fitted by magnetic adsorption or mechanical force on the core; S4: Let the bonding state stand, so that the first dispensed glue can evenly fill the gap between the core and the parts, squeeze out the gas in the gap, and avoid bubbles formed by air; S5: Dispense glue again and solidify to form a seal for the core.

[0007] Furthermore, the specific process of step S1 is as follows: The weight of the first glue dispensing is controlled by the program, and the glue amount that meets the weight is dispensed into the bottom of the part.

[0008] Furthermore, the specific process of step S2 is as follows: Within 5 minutes of the first dispensing, the core is assembled into the part using assembly tooling or automated assembly.

[0009] Furthermore, the specific process of step S3 is as follows: Use external force to make the core and parts fit tightly.

[0010] Furthermore, the specific process of step S4 is as follows: Allow the assembly of the core and parts to stand in close contact for ≥3 minutes, so that the bottom glue can fill the gap from bottom to top, squeeze out the air, and avoid the formation of bubbles due to trapped air when dispensing glue on the top.

[0011] Furthermore, the specific process of step S5 is as follows: Apply glue on the top of the core surface, let it stand for 5 minutes to level, and solidify to form an insulating sealing layer for the core Furthermore, the curing in step 5 is specifically to enter the UV oven for preliminary curing after the glue is leveled, and then further cure at room temperature.

[0012] Compared with the prior art, the beneficial effects of the present invention are as follows: 1) The present invention first pre-glueizes the parts, then assembles the core, and then precisely fits the core and the parts. During the static process, the glue fills the gap from bottom to top, squeezes out the air, and avoids the formation of gap bubbles from the root. Then, a proper amount of glue is applied to the surface of the core, and the glue is spread horizontally and connected with the glue applied for the first time at the edge, avoiding the top glue from covering from top to bottom, filling the surrounding gaps and forming bubbles. The viscosity of the glue is relatively viscous, and the bubbles cannot burst, resulting in solidified layer bubbles. Using this type of glue dispensing process can greatly improve the pass rate due to poor appearance bubbles.

[0013] 2) The hard magnetic component glued by the glue curing process of the present invention has a smooth glued surface without pits, no cracks between the glue and the product surface, good bonding strength, no bubbles in the product, and no peeling and air leakage on the product surface during the operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a schematic diagram of product assembly in an embodiment of the present invention; Figure 2 This is a schematic diagram of the first dispensing of glue on a part in an embodiment of the present invention; Figure 3 This is a schematic diagram of the core body being loaded and placed in a static state in an embodiment of the present invention; Figure 4 This is a schematic diagram of the core body surface being placed in a static state with glue being dispensed in an embodiment of the present invention; Figure 5 This is a schematic diagram of a finished product with no bubbles on the adhesive surface in an embodiment of the present invention; Figure 6This is a schematic diagram of bubbles on the glue surface of a finished product in a comparative example of the present invention that does not use the glue dispensing process of the present invention. DETAILED DESCRIPTION

[0015] To make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described in detail below. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other implementation methods obtained by ordinary technicians in this field without creative work belong to the scope of protection of the present invention. Example 1

[0016] like Figure 1-Figure 5 As shown, enter the verified bottom glue amount into the glue dispensing program, and dispense epoxy resin UV glue with a viscosity of 4000-6000 into the bottom of the part. Assemble the core to the bottom of the part with the help of assembly tools. Because the core of the project is a magnetic steel, the assembled part is placed on an iron plate. The magnetic steel has an automatic downward suction force, so the core and the part are prevented from fitting tightly during the static process. The static process is expected to take about 5 minutes. Start the top glue dispensing and let it stand for about 3 minutes. After the top glue is leveled, send it into the UV furnace for curing for about 40 seconds. After curing at room temperature for 24 hours, observe the glue surface of the product, which is smooth, elastic, and free of bubbles. The finished glue dispensing product is shown in the figure below. Figure 5 shown. Comparative Example 1

[0017] The conventional dispensing process is adopted, and the dispensing process is as follows: S1: Assemble core parts; S2: The core and the parts are closely fitted by magnetic adsorption or mechanical force on the core; S3: Apply a proper amount of glue on the surface of the assembled core; S4: Let it stand for about 5 minutes to allow the glue to fully spread and infiltrate, leaving enough time for the bubbles in the gap to burst; S5: UV curing for about 40 seconds, curing at room temperature for 24 hours, forming a sealing layer with good elasticity.

[0018] The finished dispensing product of comparative example 1 is shown in FIG. Figure 6 shown.

[0019] Compare the actual photos of the process of Example 1 of the present invention Figure 5 The actual photo of the conventional dispensing process of comparative example 1 Figure 6 You can find: The sealant layer of the process of the present invention has no bubbles, a smooth surface and good elasticity; Conventional dispensing process also adopts auxiliary bubble removal method, but there are still bubbles on the glue surface, and the appearance does not meet the customer's requirements. The glue surface is smooth and has good elasticity; Analyzing the root cause, that is, the reason explained above in the present invention, the essential reason for the bubbles is that the gap gas is squeezed upward during the glue sinking process, but it cannot burst, and finally forms Figure 6 Therefore, the present invention adopts pre-dispensing glue to fill the gap from bottom to top, and the gap gas is naturally exhausted, and then the secondary dispensing glue is sealed, and the glue is spread horizontally to avoid the product with bubbles. The effect is as follows Figure 5 . It should be noted that the dispensing equipment and related dispensing procedures, assembly tooling, etc. involved in this application are all existing technologies and will not be described in detail here.

[0020] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art who is familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A glue dispensing process suitable for dispensing medium viscosity glue into a dense cavity to remove bubbles, characterized in that: The specific steps include: S1: Apply a proper amount of glue to the part cavity; S2: assemble core parts; S3: The core and the parts are closely fitted by magnetic adsorption or mechanical force on the core; S4: Let the parts stand in the bonding state, so that the glue applied in step S1 can evenly fill the gap between the core and the parts, squeeze out the gas in the gap, and avoid bubbles formed by air; S5: Dispense glue again and solidify to form a seal for the core.

2. A glue dispensing process method suitable for dispensing medium viscosity glue into a dense cavity to remove bubbles according to claim 1, characterized in that: The specific process of step S1 is as follows: The weight of the first glue dispensing is controlled by the program, and the glue amount that meets the weight is dispensed into the bottom of the part.

3. The method for dispensing glue into a dense cavity and removing bubbles according to claim 1 is characterized in that: The specific process of step S2 is as follows: The core is assembled into the part using assembly tooling or automated assembly methods.

4. A glue dispensing process method suitable for dispensing medium viscosity glue into a dense cavity to remove bubbles according to claim 3, characterized in that: The process in step S2 is completed within 5 minutes of the first dispensing in step S1.

5. The method for dispensing glue into a dense cavity and removing bubbles according to claim 1 is characterized in that: The specific process of step S3 is as follows: Use external force to make the core and parts fit tightly.

6. The method for dispensing glue into a dense cavity and removing bubbles with medium viscosity glue according to claim 1, characterized in that: The specific process of step S4 is as follows: Allow the assembly to stand in a close-fitting state, allowing the bottom glue to fill the gap from bottom to top, squeezing out the air and avoiding the formation of bubbles due to trapped air when dispensing glue on the top.

7. A glue dispensing process for removing bubbles from a medium viscosity glue dispensed into a dense cavity according to claim 6, characterized in that: In step S4, the assembly of the core body and the component is allowed to stand in a close contact state for ≥3 minutes.

8. The method for dispensing glue into a dense cavity and removing bubbles according to claim 1, characterized in that: The specific process of step S5 is as follows: Apply glue on the top of the core surface, let it stand for 5 minutes to level, and solidify to form an insulating sealing layer for the core.

9. A glue dispensing process for removing bubbles from medium viscosity glue in a sealed cavity according to claim 8, characterized in that: In step 5, the curing is specifically to enter the UV oven for preliminary curing after the glue is leveled, and then further cure at room temperature.

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