Auxiliary heating structure of injection mold

Abstract

The utility model discloses an auxiliary heating structure of an injection mold, which comprises a heating rod arranged in a fixed mold core, the heating rod penetrates through a cavity of the fixed mold core, and a space between a bulge structure in the cavity and the inner side wall closest to the bulge structure in the cavity is set as a heating section needing to be heated. The projection of the heating section in the depth direction of the cavity of the fixed mold core is partially or completely overlapped with the projection of the heating rod in the depth direction of the cavity of the fixed mold core, the cavity penetrates through the top wall of the fixed mold core to form a discharging port for taking out a product, the heating rod is located on the side, away from the discharging port, of the fixed mold core, and the heating rod is detachably connected with the fixed mold core. According to the utility model, the overall temperature is high when the injection molding material flows to the fusion position, so that the fusion position is not easy to form a fusion line.

Description

A heating structure for injection molds Technical Field

[0001] This utility model relates to the field of injection molds, and in particular to an auxiliary heating structure for injection molds. Background Technology

[0002] In today's mobile phone market, to enhance user experience, manufacturers typically include a free protective case with the phone when it leaves the factory. Considering cost factors, these cases are mostly made of low-cost plastic materials and manufactured using injection molding.

[0003] The rear camera of a mobile phone is generally designed to protrude outwards. To prevent the protective case from interfering with the normal use of the camera, a cutout needs to be made in the corresponding position, which forms the camera clearance hole. During the injection molding process, plastic material is injected into the mold cavity from the sprue, and then flows upwards along both sides of the camera clearance hole on the protective case, finally converging above the camera hole. At the point where the material converges, a weld line is formed. From the appearance, this weld line looks like a scratch, negatively affecting the appearance quality of the product.

[0004] In injection-molded products, wherever a porous structure exists, the material is diverted around the pores during the filling process, easily leading to weld lines at the final fusion point. In the manufacturing process of mobile phone cases, a fixed mold core is placed inside a fixed mold blank. This fixed mold core has a raised structure corresponding to the phone's camera lens to block material flow. When material is injected from the injection molding machine barrel into the cavity of the fixed mold core, it encounters the obstruction of the sidewall of the raised structure and diverts in a direction similar to the arrow in Figure 1, flowing around the raised structure. During this process, some energy is lost, especially since the space between the top wall of the phone case and the side of the raised structure near the top wall is smaller. This results in a smaller width of material flowing to this point compared to the bottom, leading to less overall material flowing there. This makes it easier for the temperature to drop, the flow rate to slow down, and ultimately, the fusion effect to deteriorate, making the weld lines more noticeable. Summary of the Invention

[0005] In order to improve the fusion effect at the fusion point during the injection molding process of mobile phone cases, making the weld line shallower or even disappearing, this utility model provides an auxiliary heating structure for injection molds.

[0006] This utility model provides a technical solution that adopts the following approach:

[0007] An auxiliary heating structure for injection molds includes a heating rod disposed within a fixed mold core. The heating rod penetrates the cavity of the fixed mold core. The space between a protruding structure within the cavity and the inner wall of the cavity closest to the protruding structure is designated as a heating section to be heated. The projection of the heating section in the depth direction of the fixed mold core cavity partially or completely overlaps with the projection of the heating rod in the depth direction of the fixed mold core cavity. The cavity penetrates the top wall of the fixed mold core to form an ejection port for product removal. The heating rod is located on the side of the fixed mold core away from the ejection port, and the heating rod is detachably connected to the fixed mold core.

[0008] During injection molding, a heating rod is installed inside the fixed mold core to provide additional heat to the heating section. When the injection material flows close to the heating section, the heat provided by the heating rod slows down the cooling rate of the injection material and increases its temperature. This results in a higher overall temperature of the injection material when it flows to the fusion point, making it less likely for a fusion line to form and thus improving the fusion effect.

[0009] Preferably, the fixed mold core has a through hole for inserting a heating rod, and the fixed mold blank has a clearance hole corresponding to the through hole for inserting the heating rod.

[0010] Insert the heating rod through the clearance hole and then into the fixed mold core. Since the heating rod is connected to a power cord, inserting the heating rod through the clearance hole allows the power cord to be exposed outside the overall mold, avoiding the need to set up other structures to allow the power cord to pass through. This makes it easier to set up the heating rod, and also makes it easier to disassemble and install the heating rod.

[0011] Preferably, the heating rod extends through both sides of the mold blank along its width.

[0012] The heating rods penetrate both sides of the fixed mold blank, allowing the two sides of the fixed mold blank to support the heating rods. At the same time, it ensures that the heating rods completely penetrate the fixed mold core inside the mold, making the heating rods easy to install.

[0013] Preferably, a temperature sensing needle is inserted into the fixed mold blank near the clearance hole, and the temperature sensing needle extends into the fixed mold core.

[0014] The temperature sensing needle is used to sense the temperature of the heating rod, and then feeds the feedback to the control terminal to control the increase or decrease of the heating rod temperature, so that the temperature of the heating rod is closer to the optimal heating temperature of the material.

[0015] Preferably, the temperature sensing needle is located on the side of the clearance hole away from the discharge port.

[0016] The temperature sensing needle is located on the side away from the discharge port to avoid the material heat affecting the temperature sensing needle if the temperature sensing needle is located in the middle of the heating rod of the material box, which would interfere with the temperature sensing of the heating rod.

[0017] Preferably, the injection port is located near the center of the fixed mold core, and the temperature sensing needle is located on the side of the clearance hole away from the injection port.

[0018] Placing the temperature sensing needle on the side away from the injection port can prevent the heat received by the needle from being affected by the temperature of the high-temperature material at the injection port.

[0019] Preferably, the end of the temperature sensing needle connected to its own power cord is also provided with a limiting part, the fixed mold core has a test hole for the temperature sensing needle to be inserted, and the area of ​​the limiting part near the test hole is larger than the end area of ​​the test hole.

[0020] The limiting part can limit the insertion depth of the temperature sensing needle, making the insertion operation of the temperature sensing needle more convenient.

[0021] In summary, this utility model has the following beneficial technical effects:

[0022] During injection molding, a heating rod is installed inside the fixed mold core to provide additional heat to the heating section. When the injection material flows close to the heating section, the heat provided by the heating rod slows down the cooling rate of the injection material and increases its temperature. This results in a higher overall temperature of the injection material when it flows to the fusion point, making it less likely for a fusion line to form and thus improving the fusion effect. Attached Figure Description

[0023] Figure 1 is a schematic diagram illustrating the flow direction of the injection molding material described in the background art.

[0024] Figure 2 is a schematic diagram of the overall structure of an auxiliary heating structure for injection molds according to this utility model.

[0025] Explanation of reference numerals in the attached drawings: 1. Fixed mold core; 2. Heating rod; 3. Outlet; 4. Insertion hole; 5. Fixed mold blank; 6. Clearance hole; 7. Temperature sensing needle; 8. Restriction part; 9. Test hole. Detailed Implementation

[0026] The present invention will be further described in detail below with reference to Figure 2.

[0027] This utility model discloses an auxiliary heating structure for injection molds.

[0028] Referring to Figure 2, an auxiliary heating structure for an injection mold includes a heating rod 2 disposed in a fixed mold core 1. The heating rod 2 penetrates the cavity of the fixed mold core 1. The space between the protruding structure in the cavity and the inner wall of the cavity closest to the protruding structure is defined as the heating section to be heated. The projection of the heating section in the depth direction of the cavity of the fixed mold core 1 partially or completely overlaps with the projection of the heating rod 2 in the depth direction of the cavity of the fixed mold core 1. The cavity penetrates the top wall of the fixed mold core 1 to form an outlet 3 for product removal. The heating rod 2 is located on the side of the fixed mold core 1 away from the outlet 3. The heating rod 2 is detachably connected to the fixed mold core 1.

[0029] During injection molding, heating rod 2 is installed inside the fixed mold core 1, so that heating rod 2 provides additional heat to the heating section. When the injection material flows to the vicinity of the heating section, the heat provided by heating rod 2 slows down the cooling rate of the injection material and increases the temperature of the injection material, so that the overall temperature of the injection material is higher when it flows to the fusion point, making it less likely to form a fusion line at the fusion point, thereby improving the fusion effect.

[0030] Referring to Figure 2, in this embodiment, the fixed mold core 1 has a through hole 4 for inserting the heating rod 2, and the fixed mold blank 5 has a clearance hole 6 corresponding to the through hole 4 for inserting the heating rod 2.

[0031] After inserting the heating rod 2 through the clearance hole 6, it is then inserted into the fixed mold core 1. Since the heating rod 2 is connected to a power cord, inserting the heating rod 2 through the clearance hole 6 allows the power cord to be naturally exposed outside the overall mold, avoiding the need to set up other structures to allow the power cord to pass through. This makes the heating rod 2 easier to set up, and also makes the heating rod 2 easy to disassemble and install.

[0032] Referring to Figure 2, in this embodiment, the heating rod 2 penetrates both sides of the fixed mold blank 5 along the width direction.

[0033] The heating rod 2 passes through both sides of the fixed mold blank 5, so that the two sides of the fixed mold blank 5 can support the heating rod 2, and at the same time ensure that the heating rod 2 completely penetrates the fixed mold core 1 inside the mold, making the heating rod 2 easy to install.

[0034] Referring to Figure 2, in this embodiment, a temperature sensing needle 7 is also inserted into the fixed mold blank 5 near the clearance hole 6, and the temperature sensing needle 7 extends into the fixed mold core 1.

[0035] The temperature sensing needle 7 is used to sense the temperature of the heating rod 2, and then feeds it back to the control terminal to control the increase or decrease of the temperature of the heating rod 2, so that the temperature of the heating rod 2 is closer to the optimal heating temperature of the material.

[0036] Referring to Figure 2, in this embodiment, the temperature sensing needle 7 is located on the side of the avoidance hole 6 away from the discharge port 3.

[0037] The temperature sensing needle 7 is located on the side away from the discharge port 3 to avoid the temperature sensing needle 7 being located in the middle of the heating rod 2 in the material box, which would affect the temperature sensing needle 7 and cause the temperature sensing needle 7 to interfere with the temperature sensing of the heating rod 2.

[0038] Referring to Figure 2, in this embodiment, the injection port is located near the center of the fixed mold core 1, and the temperature sensing needle 7 is located on the side of the avoidance hole 6 away from the injection port.

[0039] The temperature sensing needle 7 is located on the side away from the injection port to prevent the heat received by the temperature sensing needle 7 from being affected by the temperature of the high-temperature material at the injection port.

[0040] Referring to Figure 2, in this embodiment, the end of the temperature sensing needle 7 connected to its own power cord is also provided with a limiting part 8, and the fixed mold core 1 has a test hole 9 for the temperature sensing needle 7 to be inserted. The area of ​​the limiting part 8 on the side near the test hole 9 is larger than the end area of ​​the test hole 9.

[0041] The limiting part 8 can limit the insertion depth of the temperature sensing needle 7, making the insertion operation of the temperature sensing needle 7 more convenient.

[0042] The above are all preferred embodiments of this utility model, and are not intended to limit the scope of protection of this utility model. Therefore, all equivalent changes made to the structure, shape and principle of this utility model should be covered within the scope of protection of this utility model.

Claims

1. An auxiliary heating structure for injection molds, characterized in that: The device includes a heating rod disposed within a fixed mold core, the heating rod penetrating the cavity of the fixed mold core, the space between a protruding structure within the cavity and the inner wall of the cavity closest to the protruding structure being designated as a heating section to be heated, the projection of the heating section in the depth direction of the fixed mold core cavity partially or entirely overlapping the projection of the heating rod in the depth direction of the fixed mold core cavity, the cavity penetrating the top wall of the fixed mold core forming an outlet for product removal, the heating rod being located on the side of the fixed mold core away from the outlet, and the heating rod being detachably connected to the fixed mold core.

2. The auxiliary heating structure for injection molds according to claim 1, characterized in that: The fixed mold core has a through hole for inserting a heating rod, and the fixed mold blank has a clearance hole corresponding to the through hole for inserting the heating rod.

3. The auxiliary heating structure for injection molds according to claim 2, characterized in that: The heating rod penetrates both sides of the fixed mold blank along the width direction.

4. The auxiliary heating structure for injection molds according to claim 2, characterized in that: A temperature-sensing needle is also inserted near the clearance hole on the fixed mold blank, and the temperature-sensing needle extends into the fixed mold core.

5. The auxiliary heating structure for injection molds according to claim 4, characterized in that: The temperature sensing needle is located on the side of the clearance hole away from the discharge port.

6. The auxiliary heating structure for injection molds according to claim 5, characterized in that: The injection port is located near the center of the fixed mold core, and the temperature sensing needle is located on the side of the clearance hole away from the injection port.

7. The auxiliary heating structure for injection molds according to claim 6, characterized in that: The end of the temperature-sensing needle connected to its own power cord is also provided with a limiting part, and the fixed mold core has a test hole for the temperature-sensing needle to be inserted. The area of ​​the limiting part near the test hole is larger than the end area of ​​the test hole.

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