A metal injection molded part

Abstract

The utility model provides a kind of metal injection molding part, including injection molding main body piece and metal insert, metal insert includes the embedding portion and protruding portion connected, embedding portion is embedded in injection molding main body piece, embedding portion and injection molding main body piece between form parting surface, protruding portion is located injection molding main body piece close to parting surface one side, recess is provided on the circumferential surface of protruding portion, recess is used to accommodate overflow injection molding material from parting surface.The utility model is provided with recess on the protruding portion of the metal insert of the metal injection molding part, equivalent to set up a gully barrier on the path of injection molding material melt flow, when injection molding material melt is injected into injection molding mold, injection molding material melt flowing to parting surface will first fill recess, to continue to overflow to form burr, so recess on metal insert digests the kinetic energy and pressure of injection molding material melt, significantly increase the difficulty of injection molding material melt overflow parting surface, to reduce the generation of burr.

Description

Technical Field

[0001] This utility model relates to the field of injection molding technology, and in particular to a metal injection molded part. Background Technology

[0002] In injection molding, flash (also known as overflow, burrs, or burrs) is one of the most common and difficult-to-eliminate defects. Flash refers to the excess thin sheet of plastic that overflows from the mold during high-pressure injection, breaking through the original mating interfaces and flowing along the parting line, ejector pin holes, slide clearances, or tiny gaps between metal inserts and the mold cavity. The physical cause is that when the melt pressure exceeds the local clamping force of the mold or the sealing force of the mating interfaces, the significantly reduced viscosity of the plastic instantly "drills" into any escape channel; even a gap of 0.01mm-0.02mm is enough to cause overflow.

[0003] For plastic-coated metal inserts, the issue of flash is particularly prominent. Metal components such as copper busbars, busbars, or terminals need to be placed in the mold cavity before injection molding. Their dimensional tolerances, surface flatness, and positioning accuracy directly determine the fit clearance between them and the mold cavity. Theoretically, as long as this clearance is compressed to within 0.02mm, plastic seepage can be avoided. However, in mass production scenarios (annual demand of hundreds of thousands to tens of millions of pieces), the rolling tolerances of the copper busbar itself, variations in surface plating thickness, and the cumulative deformation caused by handling and preheating make "±0.02mm" precision control almost unsustainable, and the cost increases exponentially. Utility Model Content

[0004] The purpose of this utility model is to provide a metal injection molded part that solves the problem of flash in existing metal injection molded parts.

[0005] To solve the above-mentioned technical problems, the present invention provides a metal injection molded part, comprising:

[0006] Injection molded main components;

[0007] A metal insert includes a connected embedded portion and a protruding portion. The embedded portion is embedded in the injection-molded body and a parting surface is formed between the embedded portion and the injection-molded body. The protruding portion is located on the side of the injection-molded body closer to the parting surface. A groove is provided on the peripheral side of the protruding portion for accommodating injection molding material overflowing from the parting surface.

[0008] In some embodiments, the groove depth is 0.1 mm to 0.3 mm.

[0009] In some embodiments, the distance between the groove and the parting surface is 0.3 mm to 0.5 mm.

[0010] In some embodiments, the cross-sectional shape of the groove is V-shaped, U-shaped, or square.

[0011] In some embodiments, the groove is provided with a raised rib near the groove edge of the parting surface and / or away from the groove edge of the parting surface, and the raised rib extends along the extension direction of the groove.

[0012] In some embodiments, the protrusion height of the rib is 0.01mm to 0.03mm.

[0013] In some embodiments, the groove is arranged in a ring shape extending circumferentially along the protrusion.

[0014] In some embodiments, the groove includes:

[0015] A horizontal segment extends along the width direction of the protrusion, and two horizontal segments are respectively provided on two opposite surfaces of the protrusion in the thickness direction of the protrusion.

[0016] A vertical segment extends along the thickness direction of the protrusion. The protrusion has two vertical segments on two opposing surfaces in the width direction of the protrusion, and each vertical segment is connected to two horizontal segments at both ends.

[0017] In some embodiments, the protrusion is provided with a positioning hole, which is located on the side of the groove away from the parting surface.

[0018] In some embodiments, multiple grooves are provided along a direction away from the parting surface.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] The protruding part of the metal insert of this utility model is provided with a groove, which is equivalent to setting a trench barrier in the flow path of the injection plastic melt. When the injection plastic melt is injected into the injection mold, the injection plastic melt flowing towards the parting surface will first fill the groove before it can continue to overflow and form flash. In this way, the groove on the metal insert absorbs the kinetic energy and pressure of the injection plastic melt, significantly increasing the difficulty of the injection plastic melt overflowing the parting surface, thereby reducing the generation of flash. Attached Figure Description

[0021] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0022] Figure 1 This is a schematic diagram of the structure of the metal injection molded part in the embodiment of this utility model;

[0023] Figure 2 for Figure 1 A cross-sectional view of a metal injection molded part;

[0024] Figure 3 for Figure 2 A magnified view of a section at point A in the middle;

[0025] Figure 4 for Figure 1 Schematic diagram of the structure of the metal insert;

[0026] Figure 5 for Figure 4 A magnified view of a section at point B in the middle.

[0027] Explanation of reference numerals in the accompanying drawings of this utility model:

[0028] Metal injection molded part 100, injection molded main body 1, parting surface 11, metal insert 2, embedded part 21, protrusion 22, groove 23, horizontal section 231, vertical section 232, rib 24, positioning hole 25.

[0029] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0030] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0031] It should be noted that if the embodiments of this utility model involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0032] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of indicated technical features. Therefore, features defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0033] This invention provides a metal injection molded part that can be used in metal insert injection molding and encapsulation processes to solve the problem of injection flash. Figures 1 to 5 A preferred embodiment of the metal injection molded part provided by this utility model is shown.

[0034] Please see Figures 1 to 5 In some embodiments, the metal injection molded part 100 includes an injection molding body 1 and a metal insert 2. The metal insert 2 includes a connected embedding portion 21 and a protrusion 22. The embedding portion 21 is embedded in the injection molding body 1, and a parting surface 11 is formed between the embedding portion 21 and the injection molding body 1. The protrusion 22 is located on the side of the injection molding body 1 close to the parting surface 11. A groove 23 is provided on the peripheral side of the protrusion 22. The groove 23 is used to accommodate the injection molding material overflowing from the parting surface 11.

[0035] Specifically, the metal injection molded part 100 is integrally formed by injection molding. The injection molded main part 1 is formed by cooling the injection plastic melt. The metal insert 2 can be a copper busbar, etc. The following will take the case of the metal insert 2 being a copper busbar and the metal injection molded part 100 being used in the process of plastic coating copper busbar as an example.

[0036] The metal insert 2 includes a connected embedded portion 21 and a protrusion 22. The embedded portion 21 is the part of the metal insert 2 covered by the injection-molded main body 1, while the protrusion 22 is the part of the metal insert 2 not covered by the injection-molded main body 1. The metal injection-molded part 100 may include one or more metal inserts 2, and each metal insert 2 may include one or more protrusions 22. The following description will take a metal insert 2 including one protrusion 22 as an example.

[0037] The surface of the injection-molded main body 1 near the protrusion 22 is the parting surface 11, and the interface between the protrusion 22 and the insert 21 is located on the parting surface 11. Hereinafter, the direction perpendicular to the parting surface 11 is defined as the front-back direction, the orientation of the parting surface 11 is defined as rearward, the width direction of the protrusion 22 is defined as the left-right direction, and the thickness direction of the protrusion 22 is defined as the up-down direction.

[0038] The protrusion 22 is located on the rear side of the parting surface 11. A groove 23 extending circumferentially along the protrusion 22 is provided on the peripheral side of the protrusion 22. The distance between the groove 23 and the parting surface 11 in the front-to-back upward direction is not greater than a preset distance threshold. Thus, the groove 23 is equivalent to setting a trench barrier in the path of the injection plastic melt. When the injection plastic melt is injected into the injection mold, the injection plastic melt flowing towards the parting surface 11 will first fill the groove 23 before it can continue to overflow and form flash. In this way, the groove 23 on the metal insert 2 absorbs the kinetic energy and pressure of the injection plastic melt, significantly increasing the difficulty of the injection plastic melt overflowing the parting surface 11, thereby reducing the generation of flash.

[0039] The metal injection molded part 100 adopts a low-cost, high-efficiency, and high-reliability anti-flash structure design, which presses grooves into the metal insert 2 in the sealing area, which is equivalent to creating a "moat" on the edge of the metal insert 2, reducing the generation of flash by about 92%. This anti-flash structure design can be widely used in the injection molding and encapsulation process of the metal insert 2.

[0040] The protrusion 22 of the metal insert 2 of the metal injection molded part 100 of this utility model is provided with a groove 23, which is equivalent to setting a trench barrier in the path of the injection plastic melt flow. When the injection plastic melt is injected into the injection mold, the injection plastic melt flowing towards the parting surface 11 will first fill the groove 23 before it can continue to overflow and form flash. In this way, the groove 23 on the metal insert 2 absorbs the kinetic energy and pressure of the injection plastic melt, significantly increasing the difficulty of the injection plastic melt overflowing the parting surface 11, thereby reducing the generation of flash.

[0041] The protrusion 22 is provided with a groove 23. The protrusion 22 may have one groove 23 or multiple grooves 23, that is, multiple grooves 23 are provided along the direction away from the parting surface 11 (i.e., the front-back direction).

[0042] The groove 23 extends circumferentially along the protrusion 22, and the groove 23 may be provided on one or more surfaces of the protrusion 22. Alternatively, please refer to... Figures 1 to 5 In some embodiments, the groove 23 is arranged in a ring shape extending circumferentially along the protrusion 22.

[0043] Specifically, the groove 23 is arranged in a ring shape extending around the circumference of the protrusion 22. This arrangement of the groove 23 can not only effectively prevent the molten plastic from overflowing outwards through the groove 23, but also makes the groove 23 easy to process and shape.

[0044] Further, please refer to Figures 1 to 5In some embodiments, the groove 23 includes a horizontal segment 231 and a vertical segment 232. The horizontal segment 231 extends along the width direction of the protrusion 22, and the protrusion 22 has two horizontal segments 231 respectively on two opposite surfaces in the thickness direction of the protrusion 22. The vertical segment 232 extends along the thickness direction of the protrusion 22, and the protrusion 22 has two vertical segments 232 respectively on two opposite surfaces in the width direction of the protrusion 22. Each vertical segment 232 is connected to two horizontal segments 231 at both ends.

[0045] Specifically, the groove 23 includes two horizontal segments 231 extending in the left-right direction and two vertical segments 232 extending in the up-down direction. The two horizontal segments 231 are vertically spaced and opposite each other, and the two vertical segments 232 are horizontally spaced and opposite each other. The two horizontal segments 231 and the two vertical segments 232 are connected end to end, thereby forming a square-ring groove 23.

[0046] The distance between the groove 23 and the parting surface 11 in the front-to-back upward direction is not greater than a preset distance threshold. The specific setting method of the preset distance threshold can be set according to the actual processing requirements. Optionally, please refer to Figures 1 to 5 In some embodiments, the distance between the groove 23 and the parting surface 11 is 0.3mm to 0.5mm.

[0047] Specifically, the distance between the groove 23 and the parting surface 11 in the front-to-back upward direction is 0.3mm to 0.5mm. By optimizing the range of values ​​for the distance between the groove 23 and the parting surface 11 in the front-to-back upward direction, it is possible to avoid the problem of the groove 23 being too close to the parting surface 11, which could easily lead to curling, and also to avoid the problem of the groove 23 being too far from the parting surface 11, which could result in poor sealing performance. For example, the distance between the groove 23 and the parting surface 11 in the front-to-back upward direction can be 0.30mm, 0.31mm, 0.32mm, 0.33mm, 0.34mm, 0.35mm, 0.36mm, 0.37mm, 0.38mm, 0.39mm, 0.40mm, 0.41mm, 0.42mm, 0.43mm, 0.44mm, 0.45mm, 0.46mm, 0.47mm, 0.48mm, 0.49mm, or 0.50mm, etc.

[0048] The groove depth of groove 23 can be set according to actual conditions. Optionally, please refer to [link / reference]. Figures 1 to 5 In some embodiments, the groove depth of the groove 23 is 0.1 mm to 0.3 mm.

[0049] Specifically, the groove depth of groove 23 can be 0.1mm to 0.3mm. By optimizing the range of groove depth, not only can the problem of groove 23 being too shallow, rendering its barrier function against the molten plastic ineffective, be avoided, but the problem of groove 23 being too deep, affecting the strength of the metal insert 2, can also be avoided. For example, the groove depth of groove 23 can be 0.10mm, 0.11mm, 0.12mm, 0.13mm, 0.14mm, 0.15mm, 0.16mm, 0.17mm, 0.18mm, 0.19mm, 0.20mm, 0.21mm, 0.22mm, 0.23mm, 0.24mm, 0.25mm, 0.26mm, 0.27mm, 0.28mm, 0.29mm, or 0.30mm, etc.

[0050] The cross-sectional shape of the groove 23 can be set according to the actual situation. For example, the cross-sectional shape of the groove 23 can be V-shaped, U-shaped, or square. Setting the cross-section of the groove 23 to U-shaped is better than setting the cross-section of the groove 23 to square, and setting the cross-section of the groove 23 to V-shaped is better than setting the cross-section of the groove 23 to U-shaped.

[0051] Optionally, please refer to Figures 1 to 5 In some embodiments, the cross-sectional shape of the groove 23 is V-shaped. The included angle between the two opposite sidewalls of the groove 23 in the groove width direction is an acute angle, and an acute angle is more likely to produce plastic deformation to achieve a seal.

[0052] Optionally, please refer to Figures 1 to 5 In some embodiments, the groove 23 is provided with a raised rib 24 near the groove edge of the parting surface 11 and / or away from the groove edge of the parting surface 11, and the raised rib 24 extends along the extension direction of the groove 23.

[0053] Specifically, the groove 23 has raised ribs 24 at the front and / or rear groove edges. After the metal insert 2 is pressed to form the groove 23, a slight metal bulge will be generated at the groove edge of the groove 23 to form ribs 24. These micro-bulges (i.e. ribs 24) will be flattened by the molding machine when the mold is closed, forming a local micro-deformation seal, filling the micro gap between the metal insert 2 and the injection mold. This is more resistant to the high pressure intrusion of the injection plastic melt than flat contact, thereby reducing the generation of flash.

[0054] The protrusion height of the rib 24 can be set according to the actual situation. Optionally, please refer to [link / reference]. Figures 1 to 5 In some embodiments, the protrusion height of the rib 24 is 0.01mm to 0.03mm.

[0055] Specifically, the protrusion height of the rib 24 can be 0.01mm to 0.03mm. For example, the protrusion height of the rib 24 can be 0.010mm, 0.011mm, 0.012mm, 0.013mm, 0.014mm, 0.015mm, 0.016mm, 0.017mm, 0.018mm, 0.019mm, 0.020mm, 0.021mm, 0.022mm, 0.023mm, 0.024mm, 0.025mm, 0.026mm, 0.027mm, 0.028mm, 0.029mm, or 0.030mm, etc.

[0056] Optionally, please refer to Figures 1 to 5 In some embodiments, the protrusion 22 is provided with a positioning hole 25, which is located on the side of the groove 23 away from the parting surface 11.

[0057] Specifically, a positioning hole 25 is provided through the protrusion 22, which extends vertically through the protrusion 22. The positioning hole 25 is located on the rear side of the groove 23. The positioning hole 25 is used to position and cooperate with the positioning post on the injection mold, thereby realizing the installation and positioning of the metal insert 2 on the injection mold.

[0058] The groove 23 formed by pressing grooves on the metal insert 2 of the metal injection molded part 100 has the following four functions:

[0059] 1. A groove 23 is pressed into the edge of the metal insert 2, which is equivalent to setting a "groove barrier" in the path of the molten plastic flow. When the molten plastic is injected into the mold under high pressure, the molten plastic flowing towards the parting surface 11 must first fill the groove 23 before it can continue to overflow and form flash. The groove 23 consumes the kinetic energy and pressure of the molten plastic, significantly increasing the difficulty of the molten plastic overflowing the parting surface 11, thereby reducing the generation of flash.

[0060] 2. Increase the contact tightness between the metal insert 2 and the injection mold. After the metal insert 2 is pressed into the groove, the groove edge of the groove 23 will produce a slight metal bulge to form a rib 24. These micro-bulges will be flattened by the molding machine when the mold is closed, forming a local micro-deformation seal, filling the micro gap between the metal insert 2 and the injection mold. It is more resistant to the high pressure intrusion of the injection plastic melt than the flat contact, thereby reducing the generation of flash.

[0061] 3. Compensating for differences in thermal expansion: During injection molding, the high-temperature melt (typically >200℃) causes the metal insert 2 to expand due to heat, while the injection mold temperature is relatively low (approximately 80℃~120℃). The difference in their coefficients of thermal expansion may lead to an increase in the gap. Localized plastic deformation at the groove provides additional "elastic compensation space." When the metal insert 2 expands due to heat, the protrusions at the groove edge can fit more tightly against the mold, offsetting the gap changes caused by the temperature difference.

[0062] 4. Reduces reliance on the precision of injection mold processing. Completely relying on the absolute flatness of the mold parting surface is costly, and the mold may wear down after long-term use. The pressure groove actively creates localized high-precision sealing points on the metal insert 2, reducing the requirements for the overall precision of the injection mold parting surface.

[0063] The above are merely preferred embodiments of this utility model and do not limit the patent scope of this utility model. Any equivalent structural transformations made based on the inventive concept of this utility model and the contents of the specification and drawings of this utility model, or direct / indirect applications in other related technical fields, are included within the patent protection scope of this utility model.

Claims

1. A metal injection molded part, characterized in that, include: Injection molded main components; A metal insert includes a connected embedded portion and a protruding portion. The embedded portion is embedded in the injection-molded body and a parting surface is formed between the embedded portion and the injection-molded body. The protruding portion is located on the side of the injection-molded body closer to the parting surface. A groove is provided on the peripheral side of the protruding portion for accommodating injection molding material overflowing from the parting surface.

2. The metal injection molded part according to claim 1, characterized in that, The groove depth is 0.1mm to 0.3mm.

3. The metal injection molded part according to claim 1, characterized in that, The distance between the groove and the parting surface is 0.3mm to 0.5mm.

4. The metal injection molded part according to claim 1, characterized in that, The cross-sectional shape of the groove is V-shaped, U-shaped, or square.

5. The metal injection molded part according to claim 1, characterized in that, The groove is provided with raised ribs at the groove edge near the parting surface and / or away from the parting surface, and the raised ribs are arranged to extend along the extension direction of the groove.

6. The metal injection molded part according to claim 5, characterized in that, The protrusion height of the rib is 0.01mm to 0.03mm.

7. The metal injection molded part according to claim 1, characterized in that, The groove is arranged in a ring shape extending circumferentially along the protrusion.

8. The metal injection molded part according to claim 7, characterized in that, The groove includes: A horizontal segment extends along the width direction of the protrusion, and two horizontal segments are respectively provided on two opposite surfaces of the protrusion in the thickness direction of the protrusion. A vertical segment extends along the thickness direction of the protrusion. The protrusion has two vertical segments on two opposing surfaces in the width direction of the protrusion, and each vertical segment is connected to two horizontal segments at both ends.

9. The metal injection molded part according to claim 1, characterized in that, The protrusion is provided with a positioning hole, which is located on the side of the groove away from the parting surface.

10. The metal injection molded part according to claim 1, characterized in that, The grooves are provided in multiple ways along a direction away from the parting surface.

Images