Semi-runner-free injection mold

Abstract

The utility model belongs to the technical field of motor rotor injection molds, and particularly relates to a semi-runner-free injection mold. The runner-free injection mold comprises a fixed mold body and a movable mold body, and the movable mold body is composed of an upper mold base plate, a cutter plate, upper mold square iron, a runner web, a needle valve, a flow dividing comb, a runner upper plate, a runner lower plate, an upper heat insulation pad, an upper heating plate and a cavity upper plate; the fixed mold is composed of a cavity lower plate, a lower heating plate, a lower heat insulation pad, lower mold square iron, an ejector rod, an ejector plate and a lower mold base plate; a hot runner is arranged between the cavity upper plate and the cavity lower plate; and a cold runner is arranged between the runner upper plate and the runner lower plate. The injection mold disclosed by the utility model not only can overcome the defects of shoulder smashing, coil winding impacting, motor stator performance reduction and the like caused by glue entering from the top of a product in a traditional cold runner mold, but also can reduce the phenomenon that a large amount of raw materials are wasted in the runner of the traditional hot runner mold, and ensures the product performance and also considers the product cost.

Description

Technical Field

[0001] This utility model belongs to the field of motor rotor injection mold technology, specifically relating to a semi-runnerless injection mold. Background Technology

[0002] Plastic-encapsulated motors utilize BMC / SMC composite materials and other encapsulation technologies to integrally encapsulate the motor's stator core and windings with engineering plastics, eliminating the need for traditional stator insulation processes and the metal casing of ordinary motors. Compared to traditional casing motors, plastic-encapsulated motors offer the following advantages: 1. Aesthetically pleasing, smaller size, and lighter weight; the length and weight are reduced by approximately 25% compared to metal-cased motors. Assembly is also convenient, making them suitable for mass automated production. 2. Low noise. The symmetrical concentric encapsulation of the stator core and the plastic molding structure improve stator coaxiality, reducing operating noise. Under mains power, the sound pressure level of plastic-encapsulated motors is 7 dB lower than that of casing motors; under variable frequency power, it is reduced by 9 dB. 3. Low vibration. Because the motor stator is now a single unit, the rotor imbalance is small, suppressing vibration. 4. Excellent insulation performance. These advantages have led to the widespread application of plastic-encapsulated motors in encapsulated electrical appliances. Generally, thermosetting materials are chosen for the encapsulation process.

[0003] Currently, common problems in the process of molding the stator of a plastic-encapsulated motor using an injection mold after winding include:

[0004] 1. Traditional cold runner injection molds, which inject the material from the top of the product, can cause defects such as product chipping, impact on the coil windings, and a decrease in the performance of the motor stator.

[0005] 2. Traditional hot runner molds result in a large amount of raw material being wasted in the runner during the injection molding process, leading to material waste in each injection.

[0006] There is an urgent need to find a method or device to solve the problems existing in the current process of molding motor stators. Utility Model Content

[0007] In order to solve the above-mentioned problems in the prior art, the purpose of this utility model is to provide a semi-runnerless injection mold.

[0008] To achieve the above objectives, the present invention adopts the following technical solution:

[0009] A semi-runnerless injection mold, characterized in that it comprises two parts: a fixed mold and a moving mold. The moving mold is composed of an upper mold base plate, a cutter plate, an upper mold square plate, a runner web, a needle valve, a runner comb, a runner upper plate, a runner lower plate, an upper heat insulation pad, an upper heating plate, and a cavity upper plate. The fixed mold is composed of a cavity lower plate, a lower heating plate, a lower heat insulation pad, a lower mold square plate, an ejector rod, an ejector plate, and a lower mold base plate. The upper mold base plate, the upper mold square plate, and the runner web form a hollow cavity. The cutter plate is located within the hollow cavity. The lower part of the runner web is arranged downwards with the runner upper plate, the runner lower plate, the upper heat insulation pad, the upper heating plate, the cavity upper plate, the cavity lower plate, the lower heating plate, the lower heat insulation pad, the lower mold square plate, and the lower mold base plate. The lower heating plate, the lower heat insulation pad, the lower mold square iron, and the lower mold pad form a hollow cavity II. The ejector plate is located inside the hollow cavity II. The upper end of the needle valve is fixed to the lower part of the cutter plate and passes through the flow channel web, the upper flow channel plate, the lower flow channel plate, the upper heat insulation pad, the upper heating plate, and the upper cavity plate in sequence. A flow divider is provided on the outside of the needle valve. The upper end of the flow divider is fixed to the lower flow channel plate and passes through the upper heat insulation pad, the upper heating plate, and the upper cavity plate in sequence. The bottom of the ejector rod is fixed to the upper part of the ejector plate and passes through the lower heating plate and the lower cavity plate in sequence. A hot runner is provided between the upper cavity plate and the lower cavity plate. A cold runner is provided between the upper flow channel plate and the lower flow channel plate.

[0010] Preferably, a recessed platform structure is provided in the middle of the upper heating plate, and the upper heat insulation pad is divided into three sections, which are located sequentially on the top of the upper heating plate;

[0011] Preferably, a cooling well is provided on the outside of the diversion comb, and the upper end of the cooling well is located above the upper heat insulation pad at the inner platform structure of the upper heating plate, and extends downward through the upper heat insulation pad, the upper heating plate, and the upper cavity plate in sequence.

[0012] Preferably, a sealing ring is provided on the outside of the needle valve, and the sealing ring is located on the upper part of the diverter comb.

[0013] Preferably, the moving mold is provided with a cutter, the upper end of which is fixed to the lower part of the cutter plate and passes through the runner web, the runner upper plate, the runner lower plate, the upper heat insulation pad, the upper heating plate, and the cavity upper plate in sequence downwards;

[0014] Preferably, a delay mechanism is provided at the connection between the upper end of the cutter and the cutter plate.

[0015] Preferably, the gap between the sealing ring and the needle valve is 0.05-0.1 mm.

[0016] Preferably, the bottom of the cutter has a wedge-shaped structure.

[0017] Preferably, there is at least one cavity between the upper cavity plate and the lower cavity plate for placing the injection-molded product.

[0018] Preferably, each product between the upper cavity plate and the lower cavity plate is provided with a set of the needle valve, diverter comb, sealing ring, cooling well, cutter, delay mechanism, and ejector rod.

[0019] Compared with the prior art, the beneficial effects of this utility model are:

[0020] The injection mold provided by this utility model can eliminate the defects of traditional cold runner molds, such as product chipping and impact on coil windings caused by the injection of glue from the top of the product, resulting in a decrease in the performance of the motor stator. It can also reduce the waste of a large amount of raw materials in the runner of traditional hot runner molds, thus ensuring product performance while taking into account product cost. Attached Figure Description

[0021] Figure 1 Axonometric view of a semi-runnerless injection mold provided in Embodiment 1 of this utility model;

[0022] Figure 2 A schematic diagram of a traditional cold runner injection mold;

[0023] Figure 3 A schematic diagram of a traditional hot runner injection mold;

[0024] Figure 4 A cross-sectional view of the semi-runnerless injection mold provided in Embodiment 1 of this utility model;

[0025] Figure 5 for Figure 4 A magnified view of a portion of the hot runner;

[0026] Figure 6 This is a schematic diagram of the cold runner system of a semi-runnerless injection mold provided in Embodiment 1 of this utility model;

[0027] Figure 7 A cross-sectional view of the semi-runnerless injection mold provided in Embodiment 2 of this utility model;

[0028] Figure 8 A cross-sectional view of the semi-runnerless injection mold provided in Embodiment 3 of this utility model;

[0029] Figure 9 This is a cross-sectional view of the semi-runnerless injection mold provided in Embodiment 4 of this utility model. Detailed Implementation

[0030] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the following description, only certain exemplary embodiments of the present invention are described by way of illustration. Undoubtedly, those skilled in the art will recognize that the described embodiments can be modified in different ways without departing from the spirit and scope of the present invention. Therefore, the drawings and description are illustrative in nature and not intended to limit the scope of the claims. In this document, directional terms such as inner, outer, upper, and lower are defined based on the product; it should be understood that the use of these directional terms should not limit the scope of protection claimed in this application.

[0031] Example 1

[0032] like Figure 1 , 4 As described in section -6, this utility model provides a semi-runnerless injection mold, which includes a fixed mold and a moving mold. The moving mold is composed of an upper mold base plate 1, a cutter plate 2, an upper mold square iron 3, a runner web plate 4, a needle valve 5, a runner comb 6, a runner upper plate 7, a runner lower plate 8, an upper heat insulation pad 9, an upper heating plate 10, and a cavity upper plate 11. The fixed mold is composed of a cavity lower plate 13, a lower heating plate 14, a lower heat insulation pad 15, a lower mold square iron 16, and an ejector pin. 17. The ejector plate 18 and the lower mold pad 18 are composed of the upper mold pad 1, the upper mold square iron 3, and the runner web 4, which together form a hollow cavity. The cutter plate 2 is located inside the hollow cavity. The lower part of the runner web 4 is arranged with the following components in descending order: the upper runner plate 7, the lower runner plate 8, the upper heat insulation pad 9, the upper heating plate 10, the upper cavity plate 11, the lower cavity plate 13, the lower heating plate 14, the lower heat insulation pad 15, and the lower mold square iron 16. The lower mold pad 19; the lower heating plate 14, the lower heat insulation pad 15, the lower mold square iron 16, and the lower mold pad 19 form a hollow cavity II, and the ejector plate 18 is located inside the hollow cavity II; the upper end of the needle valve 5 is fixed to the lower part of the cutter plate 2, and passes through the flow channel web 4, the flow channel upper plate 7, the flow channel lower plate 8, the upper heat insulation pad 9, the upper heating plate 10, and the cavity upper plate 11 in sequence; the flow divider 6 is provided on the outside of the needle valve 5, the upper end of the flow divider 6 is fixed on the flow channel lower plate 8, and passes through the upper heat insulation pad 9, the upper heating plate 10, and the cavity upper plate 11 in sequence; the bottom of the ejector rod 17 is fixed to the upper part of the ejector plate 18, and passes through the lower heating plate 14 and the cavity lower plate 13 in sequence; a hot runner 20 is provided between the cavity upper plate 11 and the cavity lower plate 13; a cold runner 21 is provided between the flow channel upper plate 7 and the flow channel lower plate 8.

[0033] The upper heating plate 10 has a recessed platform structure in the middle to reduce the upward conduction of heat from the lower heating plate. The upper heat insulation pad 9 is divided into three sections, which are located sequentially on the top of the upper heating plate 10.

[0034] There is at least one cavity between the upper cavity plate 11 and the lower cavity plate 13 for placing the injection-molded product 12. In order to balance the force of the mold structure and improve production efficiency, the number of products is generally set to an even number such as 8, 10, or 12.

[0035] Each product 12 between the upper cavity plate 11 and the lower cavity plate 13 is provided with a set of needle valve 5 and flow divider 6 mechanism; each product is provided with multiple ejector rods, and in order to balance the force when the product is ejected, the ejector rods need to be evenly distributed along the product ejection section direction.

[0036] Example 2

[0037] The difference between this embodiment and Embodiment 1 is that a cooling well 22 is provided on the outer side of the flow divider 6 to facilitate the timely dissipation of heat from the raw material inside the flow divider, preventing the raw material from solidifying due to temperature fluctuations. The upper end of the cooling well 22 is located above the upper heat insulation pad 9 in the recessed structure of the upper heating plate 10, and extends downwards through the upper heat insulation pad 9, the upper heating plate 10, and the upper cavity plate 11. A sealing ring 23 is provided on the outer side of the needle valve 5, with a gap of 0.05-0.1mm between the sealing ring and the needle valve. This sealing ring 23 effectively prevents raw material from overflowing from the mold gaps. The sealing ring 23 is located on the upper part of the flow divider 6. The rest is the same as in Embodiment 1.

[0038] Example 3

[0039] The difference between this embodiment and embodiment 2 is that the moving mold is equipped with a cutter 24. When the product exits the mold, the cutter 24 can automatically cut off the nozzle during product injection, thereby improving production efficiency. In order to avoid scratches or tears on the product surface during cutting, the bottom of the cutter 23 is generally wedge-shaped. The upper end of the cutter is fixed to the lower part of the cutter plate 2 and passes through the runner web 4, the runner upper plate 7, the runner lower plate 8, the upper heat insulation pad 9, the upper heating plate 10, and the cavity upper plate 11 in sequence. The rest is the same as in embodiment 3.

[0040] Example 4

[0041] The difference between this embodiment and embodiment 3 is that a delay mechanism 25 is provided at the connection between the upper end of the cutter 24 and the cutter plate 2. When the cutter plate 2 moves downward, the needle valve 5 begins to move downward. After the needle valve 5 has moved a certain distance, the cutter plate 2 begins to push the cutter 24 and the needle valve 5 to move downward simultaneously until the needle valve 5 closes the cold runner and the cutter 24 cuts off the nozzle. Here, the delay mechanism 25 can effectively reduce the nozzle cross-section and further reduce raw material waste; the rest is the same as in embodiment 3.

[0042] The working principle of the semi-runnerless injection mold provided by this utility model is as follows: After the moving mold and the fixed mold are closed, the raw material enters the cold runner between the upper and lower runner plates through the gate, and then enters the corresponding runner comb for each product through the cold runner. Through the runner comb, the raw material enters the hot runner between the upper and lower cavity plates, and then enters the corresponding cavity for each product. After the raw material fills the cavity of each product, the cutter plate moves downward and pushes the needle valve downward. After the needle valve enters the narrow channel at the bottom of the runner comb, it stops the flow of raw material into the product. The cutter plate continues to move downward. At this time, the cutter starts to move downward and begins to cut the nozzle. When the cutter plate moves downward to the lowest point, the cutter and the needle valve stop at the same time. At this time, the cutter completely cuts off the nozzle, and the needle valve completely stops the flow in the runner comb. At the same time, the solidified raw material is pushed out of the flow in the runner comb. At this point, the moving mold moves upward, the mold begins to open, and the ejector plate on the fixed mold pushes the ejector rod upward to slowly eject the product; each branch comb's corresponding lower plate is also equipped with an ejector rod, which can eject the nozzle out of the mold while ejecting the product, thus completing a complete injection molding process.

[0043] The above descriptions are illustrative embodiments of this utility model and are not intended to limit the scope of this utility model. Any equivalent changes and modifications made by those skilled in the art without departing from the concept and principles of this utility model should fall within the protection scope of this utility model.

Claims

1. A semi-runnerless injection mold, characterized in that... include: The mold consists of two parts: a fixed mold and a moving mold. The moving mold comprises an upper mold base plate, a cutter plate, an upper mold square iron, a runner web, a needle valve, a flow divider, a runner upper plate, a runner lower plate, an upper heat insulation pad, an upper heating plate, and a cavity upper plate. The fixed mold comprises a cavity lower plate, a lower heating plate, a lower heat insulation pad, a lower mold square iron, an ejector rod, an ejector plate, and a lower mold base plate. The upper mold base plate, the upper mold square iron, and the runner web form a hollow cavity. The cutter plate is located within the hollow cavity. The lower part of the runner web is arranged downwards with the runner upper plate, the runner lower plate, the upper heat insulation pad, the upper heating plate, the cavity upper plate, the cavity lower plate, the lower heating plate, the lower heat insulation pad, the lower mold square iron, and the lower mold base plate. The lower heating plate and... The lower heat insulation pad, lower mold square iron, and lower mold pad form a hollow cavity II, and the ejector plate is located inside the hollow cavity II; the upper end of the needle valve is fixed to the lower part of the cutter plate, and passes through the flow channel web, flow channel upper plate, flow channel lower plate, upper heat insulation pad, upper heating plate, and cavity upper plate in sequence downwards; the flow divider is provided on the outside of the needle valve, the upper end of the flow divider is fixed to the flow channel lower plate, and passes through the upper heat insulation pad, upper heating plate, and cavity upper plate in sequence downwards; the bottom of the ejector rod is fixed to the upper part of the ejector plate, and passes through the lower heating plate and cavity lower plate in sequence upwards; a hot runner is provided between the cavity upper plate and the cavity lower plate; a cold runner is provided between the flow channel upper plate and the flow channel lower plate.

2. The semi-runnerless injection mold according to claim 1, characterized in that, A recessed platform structure is provided in the middle of the upper heating plate, and the upper heat insulation pad is divided into three sections, which are located sequentially on the top of the upper heating plate.

3. The semi-runnerless injection mold according to claim 1 or 2, characterized in that, A cooling well is provided on the outside of the diversion comb. The upper end of the cooling well is located above the upper heat insulation pad at the inner platform structure of the upper heating plate, and extends downward through the upper heat insulation pad, the upper heating plate, and the upper cavity plate in sequence.

4. The semi-runnerless injection mold according to claim 1, characterized in that, A sealing ring is provided on the outside of the needle valve, and the sealing ring is located on the upper part of the diverter comb.

5. The semi-runnerless injection mold according to claim 4, characterized in that, The gap between the sealing ring and the needle valve is 0.05-0.1 mm.

6. The semi-runnerless injection mold according to claim 1, characterized in that, The moving mold is equipped with a cutter. The upper end of the cutter is fixed to the lower part of the cutter plate and passes through the runner web, runner upper plate, runner lower plate, upper heat insulation pad, upper heating plate, and cavity upper plate in sequence.

7. The semi-runnerless injection mold according to claim 1 or 6, characterized in that, A delay mechanism is provided at the connection between the upper end of the cutter and the cutter plate.

8. The semi-runnerless injection mold according to claim 1 or 6, characterized in that, The bottom of the cutter has a wedge-shaped structure.

9. The semi-runnerless injection mold according to claim 1, characterized in that, There is at least one cavity between the upper cavity plate and the lower cavity plate for placing the injection-molded product.

10. The semi-runnerless injection mold according to claim 9, characterized in that, Each product between the upper cavity plate and the lower cavity plate is equipped with a set of needle valve, flow divider, sealing ring, cooling well, cutter, delay mechanism, and ejector rod.

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