Injection mold for a worm gear

Abstract

The application discloses an injection mold for a worm gear, which comprises a lower mold, an upper mold capable of being pressed with the lower mold, an injection device arranged on the upper mold, a sealed injection cavity formed when the lower mold and the upper mold are pressed, and a cooling needle fixed on the inner wall of the side of the injection cavity far from the upper mold and used for forming a deep hole of the worm gear. In the embodiment of the application, the base and the forming column of the cooling needle are integrally machined from a metal rod, a cooling flow channel penetrating through both ends is formed in the base and the forming column, and an arc top is welded on the forming column to seal the cooling flow channel. The injection mold can not only ensure the overall structural strength of the cooling needle and avoid bending deformation during injection, but also can cool the formed workpiece and ensure the structural precision of the workpiece.

Description

Technical Field

[0001] This invention relates to the field of transmission component manufacturing technology, and in particular to an injection mold for worm gear transmission components. Background Technology

[0002] A worm gear is a component of a transmission structure, commonly found in the handle actuator of automobiles, used to transmit power.

[0003] Traditional worm gear components mostly adopt an all-metal machined structure. Although this manufacturing method can ensure its structural strength, the overall cost is high and its weight is large, resulting in a large overall weight of the transmission structure. Therefore, some existing worm gear components adopt a metal structure and then injection molding process to reduce processing costs and component weight.

[0004] However, when injection molding worm gear components with axial deep holes, cooling water channels need to be installed on the rod-shaped structure formed by the deep hole. In existing technologies, the rod-shaped structure formed by the deep hole is mostly set as a machined metal heat exchange tube. However, the cooling effect of the heat exchange tube is unstable. When the cooling effect of the heat exchange tube is insufficient, the inner wall of the deep hole of the worm gear component is easily left in a molten state after injection molding, making it difficult to guarantee the quality and precision of the inner wall of the deep hole after demolding. Some solutions use 3D printing technology to manufacture rod-shaped structures with internal cooling channels (the cooling channels are loop structures, difficult to form directly within the metal rod). However, additive manufacturing materials are limited. Due to the small inner diameter and long length of the deep hole, the 3D-printed rod-shaped structure lacks structural strength and is easily bent by the injection pressure during injection molding, making it difficult to guarantee product precision. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides an injection mold for worm gear transmission components that has high structural strength and can guarantee the precision of injection molded products.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solutions.

[0007] This application provides an injection mold for a worm gear drive component, including a lower mold, an upper mold capable of pressing with the lower mold, and an injection unit. When the lower mold and the upper mold are pressed together, a sealed injection cavity is formed. Cooling pins for forming deep holes in the worm gear drive component are fixedly provided on the inner wall of the injection cavity on the side away from the upper mold.

[0008] The cooling pin includes a base fixedly connected to the inner wall of the injection cavity and a molding column disposed at one end of the base near the upper mold and coaxial with the base. The base and the molding column are provided with an inlet channel and a outlet channel through which liquid flows axially.

[0009] The molding column is provided with a transition cavity communicating with the liquid inlet channel and the liquid outlet channel at the end away from the base, and an arc-shaped top for sealing the transition cavity is also fixedly provided.

[0010] The injection molding unit is capable of injecting glue into the injection cavity to form a worm gear transmission component. The base, molding column, liquid inlet channel, liquid outlet channel, and transition cavity are integrally machined from metal rods. The arc top is formed by welding on the molding column and then shaping.

[0011] Further specifying, in the above-mentioned injection mold for worm gear transmission components, the lower mold has a first cavity on the end face near the upper mold, and the upper mold has a second cavity on the end face near the lower mold, wherein the first cavity and the second cavity can be engaged to form a sealed injection cavity;

[0012] The cooling pin is fixedly disposed on the inner wall of the first cavity on the side away from the upper mold.

[0013] Further specifying, in the above-mentioned injection mold for worm gear transmission components, the lower mold has a retaining ring fixedly provided on the end face of the side near the upper mold, which surrounds the first cavity, and the upper mold has a sealing groove on the end face of the side near the lower mold, which surrounds the second cavity and can engage with the retaining ring at the corresponding position.

[0014] Further specifying, in the above-mentioned injection mold for worm gear transmission components, the first cavity is provided with multiple cavities on the end face of the lower mold near the upper mold, and the second cavity is provided with multiple cavities on the end face of the upper mold near the lower mold;

[0015] The first cavity and the second cavity are positioned correspondingly and can be engaged to form a sealed injection cavity.

[0016] Further specifying, in the above-mentioned injection mold for a worm gear drive component, the forming column includes a prism portion fixedly disposed at one end of the base near the upper mold and used for forming the prism hole portion of the worm gear drive component, and a cylindrical portion fixedly disposed at one end of the prism portion away from the base and used for forming the circular hole portion of the worm gear drive component.

[0017] Further specifying, in the above-mentioned injection mold for worm gear transmission components, the cylindrical portion of the forming column is provided with a groove communicating with the transition cavity at the end away from the prism portion, and a piece for sealing the transition cavity is embedded in the groove.

[0018] In the case of the insert and slot being engaged, the arc top is welded to the end of the insert away from the prism.

[0019] Further specifying, in the above-mentioned injection mold for worm gear transmission components, the liquid inlet channel penetrates the base and the molding column and is coaxial with the base and the molding column, and the liquid outlet channel has multiple channels penetrating the base and the molding column, and the multiple liquid outlet channels are arranged in a ring array about the axis of the liquid inlet channel;

[0020] Alternatively, the drain channel passes through the base and the forming column and is coaxial with the base and the forming column, and the inlet channel has multiple channels that pass through the base and the forming column, and the multiple inlet channels are arranged in a ring array about the axis of the drain channel.

[0021] Further specifying, in the above-mentioned injection mold for worm gear transmission components, the liquid discharge channel is provided with multiple channels, and two adjacent liquid discharge channels in the circumferential direction of the central axis of the liquid inlet channel are interconnected;

[0022] Alternatively, the liquid inlet channel may be provided in multiple ways, with two adjacent liquid inlet channels connected to each other in the circumferential direction of the central axis of the liquid outlet channel.

[0023] Further specifying, in the above-mentioned injection mold for a worm gear transmission component, the injection unit includes an injection device disposed on the upper mold and a dispensing channel, the dispensing channel including a main pipe connected to the discharge end of the injection device and a plurality of branch pipes respectively connected to the main pipe;

[0024] Among them, the ends of the multiple branch pipes away from the main pipe correspond to the positions of multiple injection cavities and can inject glue into the corresponding injection cavities.

[0025] Further specifying, the aforementioned injection mold for a worm gear drive component further includes a demolding assembly disposed on the lower mold and / or the upper mold.

[0026] This invention has at least the following beneficial effects:

[0027] 1. The base and forming column of the cooling needle are machined from metal rods in one piece, and a cooling channel with two through ends is formed inside the base and forming column. The top of the forming column is welded to achieve the sealing of the cooling channel. This not only ensures the overall structural strength of the cooling needle and avoids bending deformation during injection molding, but also cools the formed workpiece and ensures the structural accuracy of the workpiece.

[0028] 2. During injection molding, coolant is introduced into the cooling pin through the inlet channel and discharged through the outlet channel. The coolant temperature is lower when flowing through the inlet channel, while the temperature gradually increases when flowing through the outlet channel due to heat exchange. Through heat exchange between the coolant in the inlet channel and the coolant in the outlet channel, the temperature of the coolant in the cooling pin can be made to reach equilibrium. Since multiple outlet channels are arranged in a ring array about the central axis of the cooling pin, the cooling uniformity of the inner wall of the deep hole is improved, ensuring the deep hole accuracy of the worm gear drive component. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the worm gear transmission component according to an embodiment of this application;

[0030] Figure 2 This is a cross-sectional view of the worm gear transmission component according to an embodiment of this application;

[0031] Figure 3 This is a schematic diagram of the structure of the injection mold used for the worm gear drive component according to an embodiment of this application;

[0032] Figure 4 This is a schematic diagram of the "lower mold 200" portion in the injection mold used for worm gear transmission components according to an embodiment of this application;

[0033] Figure 5 This is a partial enlarged schematic diagram of the "lower mold 200" in the injection mold for the worm gear transmission component according to an embodiment of this application;

[0034] Figure 6 This is a schematic diagram of the structure of the "cooling pin 220" in the injection mold used for worm gear transmission components according to an embodiment of this application;

[0035] Figure 7 This is a cross-sectional view of the "cooling pin 220" in the injection mold of the worm gear transmission component according to an embodiment of this application;

[0036] Figure 8 This is a cross-sectional view of the "cooling pin 220" in the injection mold of the worm gear transmission component according to an embodiment of this application;

[0037] Figure 9 This is a schematic diagram of the "upper mold 300" portion in the injection mold used for worm gear transmission components according to an embodiment of this application;

[0038] Figure 10 This is a magnified schematic diagram of a portion of the "upper mold 300" in the injection mold used for worm gear transmission components according to an embodiment of this application.

[0039] Figure Labels

[0040] Optical axis section-110, first tooth section-120, second tooth section-130, deep hole-140, round hole section-141, prism hole section-142, lower mold-200, base-221, prism section-222, cylindrical section-223, arc top-224, liquid inlet channel-225, liquid outlet channel-226, transition cavity-227, groove-228, insert-229, first cavity-210, cooling pin-220, abutment ring-230, upper mold-300, second cavity-310, sealing groove-320, injection molding device-400. Detailed Implementation

[0041] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0042] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0043] The injection mold for worm gear transmission components provided in this application will be described in detail below with reference to the accompanying drawings, through specific embodiments and application scenarios.

[0044] like Figure 1 , Figure 2 As shown, the worm gear transmission component includes an optical shaft portion 110 and a transmission gear portion fixedly disposed at one end of the optical shaft portion 110 and coaxial with the optical shaft portion 110. The transmission gear portion has a deep hole 140 coaxial with the optical shaft portion 110 at the end away from the optical shaft portion 110.

[0045] Understandably, since the deep hole 140 is a long and narrow hole, when the worm gear drive component is injection molded, it is necessary to set the molding rod of the deep hole 140 in the mold, and it is necessary to set the cooling channel in the molding rod of the deep hole 140.

[0046] Specifically, the transmission gear includes a first tooth 120 fixedly disposed at the end of the optical shaft 110 and a second tooth 130 fixedly disposed at the end of the first tooth 120 away from the optical shaft 110.

[0047] The deep hole 140 includes a circular hole 141 disposed in the optical shaft portion 110 and the first tooth portion 120, and a prism hole 142 disposed in the second tooth portion 130 and communicating with the circular hole 141. When the prism hole 142 is inserted into a mating workpiece (which fits the shape of the prism hole 142), torque transmission between the mating workpiece and the worm gear transmission component can be realized.

[0048] It is understandable that the specific structural form of the worm gear transmission component is not limited to the one mentioned above, as long as it has a deep hole 140 that extends axially and is open on one side, which will not be elaborated here.

[0049] like Figures 2 to 10 As shown, this application provides an injection mold for a worm gear drive component, including a lower mold 200, an upper mold 300 capable of pressing with the lower mold 200, and an injection unit 400 disposed on the upper mold 300. The lower mold 200 has a first cavity 210 on the end face near the upper mold 300, and the upper mold 300 has a second cavity 310 on the end face near the lower mold 200.

[0050] A cooling pin 220 for forming the deep hole 140 of the worm gear transmission component is fixedly provided on the inner wall of the first cavity 210 away from the upper mold 300. The cooling pin 220 includes a base 221 fixedly connected to the inner wall of the first cavity 210 and a forming column disposed at the end of the base 221 near the upper mold 300 and coaxial with the base 221. An inlet channel 225 and an outlet channel 226 are provided axially through the base 221 and the forming column. A transition cavity 227 communicating with the inlet channel 225 and the outlet channel 226 is provided at the end of the forming column away from the base 221. An arc-shaped top 224 for sealing the transition cavity 227 is also fixedly provided.

[0051] In the case where the lower mold 200 and the upper mold 300 are pressed together, the first cavity 210 and the second cavity 310 are engaged to form a sealed injection cavity, and the injection unit 400 can inject glue into the injection cavity to form a worm gear transmission component.

[0052] The base 221, the forming column, the liquid inlet channel 225, the liquid outlet channel 226, and the transition cavity 227 are machined from metal rods in one piece. The arc top 224 is formed by welding on the forming column and then shaping.

[0053] During injection molding, the upper mold 300 moves towards the lower mold 200 until it is pressed together. The first cavity 210 and the second cavity 310 engage to form a sealed injection cavity. When the lower mold 200 and the upper mold 300 are fully pressed together, the injection unit 400 starts and injects glue into the injection cavity, thereby realizing the injection molding of the worm gear drive component. During the injection molding process, coolant is introduced into the cooling needle 220 through the liquid inlet channel 225 and discharged through the liquid outlet channel 226. The cooling of the worm gear drive component after molding is achieved through the flow of coolant inside the cooling needle 220.

[0054] In this embodiment, an injection mold for a worm gear transmission component is used. The base 221 and the forming column of the cooling pin 220 are integrally machined from metal rods. A cooling channel with both ends is formed inside the base 221 and the forming column. The top 224 of the forming column is welded to seal the cooling channel. This not only ensures the overall structural strength of the cooling pin 220 and prevents bending deformation during injection molding, but also cools the molded workpiece and ensures the structural accuracy of the workpiece.

[0055] In a preferred embodiment, such as Figure 6 , Figure 7 As shown, the forming column includes a prism portion 222 fixedly disposed on the base 221 near the upper mold 300 and used for forming the prism hole portion 142, and a cylindrical portion 223 fixedly disposed on the prism portion 222 away from the base 221 and used for forming the circular hole portion 141.

[0056] In a preferred embodiment, such as Figure 7 As shown, the cylindrical portion 223 has a groove 228 that communicates with the transition cavity 227 at the end away from the prism portion 222, and a piece 229 for sealing the transition cavity 227 is embedded in the groove 228.

[0057] In the case where the insert 229 and the slot 228 are in the inserted state, the arc top 224 is welded to the end of the insert 229 away from the prism 222.

[0058] It is understandable that by sealing the transition cavity 227 with insert 229, when the arc top 224 is welded, the waste generated during the welding process can be prevented from falling into the cooling channel, thereby improving the overall machining accuracy of the cooling pin 220.

[0059] In a preferred embodiment, such as Figure 8 As shown, the liquid inlet channel 225 passes through the base 221 and the forming column and is coaxial with the base 221 and the forming column. The liquid outlet channel 226 has multiple channels that pass through the base 221 and the forming column. The multiple liquid outlet channels 226 are arranged in a ring array about the axis of the liquid inlet channel 225.

[0060] In this embodiment, an injection mold for a worm gear drive is used. During injection, coolant is introduced into the cooling pin 220 through the inlet channel 225 and discharged through the outlet channel 226. The coolant flowing through the inlet channel 225 has a lower temperature, while the coolant flowing through the outlet channel 226 gradually increases in temperature due to heat exchange. Through heat exchange between the coolant in the inlet channel 225 and the coolant in the outlet channel 226, the temperature of the coolant in the cooling pin 220 can be made to reach equilibrium. Since multiple outlet channels 226 are arranged in a ring array about the central axis of the cooling pin 220, the cooling uniformity of the inner wall of the deep hole 140 is improved, ensuring the accuracy of the deep hole 140 of the worm gear drive.

[0061] It is understood that the configuration of the liquid inlet channel 225 and the liquid outlet channel 226 is not limited to the one mentioned above. For example, the liquid outlet channel 226 can be configured to penetrate the base 221 and the forming column and be coaxial with the base 221 and the forming column, and the liquid inlet channel 225 can be configured to penetrate the base 221 and the forming column. The multiple liquid inlet channels 225 are arranged in a ring array about the axis of the liquid outlet channel 226. In this case, uniform cooling of the inner wall of the deep hole 140 is also achieved, which will not be elaborated here.

[0062] In a preferred embodiment, such as Figure 8 As shown, the two adjacent drain channels 226 on the circumferential direction of the central axis of the inlet channel 225 are interconnected.

[0063] It is understandable that when multiple drain channels 226 are configured to be interconnected, the flow of the drained coolant can be further improved, thereby improving the heat exchange effect.

[0064] In a preferred embodiment, such as Figure 4 , Figure 5 , Figure 9 , Figure 10 As shown, the lower mold 200 is provided with a retaining ring 230 around the first cavity 210 at a position corresponding to the first cavity 210 on the end face of the lower mold 200 near the upper mold 300, and a sealing groove 320 is provided around the second cavity 310 on the end face of the upper mold 300 near the lower mold 200 and can be engaged with the retaining ring 230 at the corresponding position.

[0065] It is understandable that when the lower mold 200 and the upper mold 300 are pressed together, the sealing groove 320 can engage with the corresponding abutment ring 230, thereby ensuring the sealing effect of the injection cavity at the corresponding position.

[0066] In a preferred embodiment, such as Figure 3 , Figure 4 , Figure 9As shown, multiple first cavities 210 are provided on the end face of the lower mold 200 near the upper mold 300, and multiple second cavities 310 are provided on the end face of the upper mold 300 near the lower mold 200. The multiple first cavities 210 and the multiple second cavities 310 are positioned corresponding to each other and can be engaged to form a sealed injection cavity.

[0067] Understandably, by setting multiple injection cavities on the injection mold, the lower mold 200 and the upper mold 300 can produce multiple worm gear transmission parts at the same time in one press, further improving production efficiency.

[0068] In a preferred embodiment, the injection molding unit 400 includes an injection molding device and a dispensing channel disposed on the upper mold 300.

[0069] The dispensing channel includes a main pipe connected to the discharge end of the injection molding device and multiple branch pipes connected to the main pipe. The ends of the multiple branch pipes away from the main pipe correspond to the positions of multiple injection cavities and can inject glue into the corresponding injection cavities.

[0070] It is understood that the configuration of the injection unit 400 is not limited to the one mentioned above. For example, the injection device and the dispensing channel can be set on the lower mold 200. In this case, the flow direction of the colloid will change, but the colloid injection into the injection cavity can still be performed. This will not be elaborated here.

[0071] In a preferred embodiment, a demolding assembly is also provided on the lower mold 200 and / or the upper mold 300.

[0072] Understandably, after the worm gear drive component is injection molded, the demolding assembly can release the limiting effect of the injection cavity on the worm gear drive component and push the worm gear drive component out of the injection cavity, making it easier to demold and unload the finished worm gear drive component.

[0073] In a preferred embodiment, a cooling assembly is also provided on the lower mold 200 and / or the upper mold 300.

[0074] The cooling component includes coolant channels located in the lower mold 200 and / or the upper mold 300. The coolant flowing through the coolant channels can cool the inside of the injection cavity, thereby achieving overall cooling and molding of the worm gear drive component.

[0075] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

[0076] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

Claims

1. An injection mold for worm gear transmission components, characterized in that, It includes a lower mold, an upper mold that can be pressed together with the lower mold, and an injection unit. When the lower mold and the upper mold are pressed together, they form a sealed injection cavity. Cooling pins for molding deep holes of worm gear transmission components are fixed on the inner wall of the injection cavity away from the upper mold. The cooling pin includes a base fixedly connected to the inner wall of the injection cavity and a molding column disposed at one end of the base near the upper mold and coaxial with the base. The base and the molding column are provided with an inlet channel and a outlet channel through which liquid flows axially. The forming column has a transition cavity communicating with the liquid inlet channel and the liquid outlet channel at the end away from the base, and also has an arc-shaped top fixedly provided for sealing the transition cavity; the forming column includes a prismatic part fixedly provided at the end of the base near the upper mold for forming the prism hole of the worm gear drive component, and a cylindrical part fixedly provided at the end of the prismatic part away from the base for forming the circular hole of the worm gear drive component; the cylindrical part of the forming column has a groove communicating with the transition cavity at the end away from the prismatic part, and an insert for sealing the transition cavity is embedded in the groove; in the state where the insert and the groove are engaged, the arc-shaped top is welded to the end of the insert away from the prismatic part. The injection molding unit is capable of injecting glue into the injection cavity to form a worm gear transmission component. The base, molding column, liquid inlet channel, liquid outlet channel, and transition cavity are integrally machined from metal rods. The arc top is formed by welding on the molding column and then shaping.

2. The injection mold for a worm gear transmission component according to claim 1, characterized in that, The lower mold has a first cavity on the end face near the upper mold, and the upper mold has a second cavity on the end face near the lower mold. The first cavity and the second cavity can be engaged to form a sealed injection cavity. The cooling pin is fixedly disposed on the inner wall of the first cavity on the side away from the upper mold.

3. An injection mold for a worm gear transmission component according to claim 1 or 2, characterized in that, The lower mold is fixedly provided with a retaining ring on the end face near the upper mold, which surrounds the first cavity. The upper mold is provided with a sealing groove on the end face near the lower mold, which surrounds the second cavity and can be engaged with the retaining ring at the corresponding position.

4. The injection mold for a worm gear transmission component according to claim 2, characterized in that, The first cavity is provided with multiple cavities on the end face of the lower mold near the upper mold, and the second cavity is provided with multiple cavities on the end face of the upper mold near the lower mold; The first cavity and the second cavity are positioned correspondingly and can be engaged to form a sealed injection cavity.

5. The injection mold for a worm gear transmission component according to claim 1, characterized in that, The liquid inlet channel passes through the base and the forming column and is coaxial with the base and the forming column. The liquid outlet channel has multiple channels that pass through the base and the forming column. The multiple liquid outlet channels are arranged in a ring array about the axis of the liquid inlet channel. Alternatively, the drain channel passes through the base and the forming column and is coaxial with the base and the forming column, and the inlet channel has multiple channels that pass through the base and the forming column, and the multiple inlet channels are arranged in a ring array about the axis of the drain channel.

6. The injection mold for a worm gear transmission component according to claim 5, characterized in that, The liquid discharge channel is provided in multiple ways, and two adjacent liquid discharge channels in the circumferential direction of the central axis of the liquid inlet channel are interconnected with each other. Alternatively, the liquid inlet channel may be provided in multiple ways, with two adjacent liquid inlet channels connected to each other in the circumferential direction of the central axis of the liquid outlet channel.

7. The injection mold for a worm gear transmission component according to claim 1, characterized in that, The injection molding unit includes an injection molding device mounted on the upper mold and a dispensing channel. The dispensing channel includes a main pipe connected to the discharge end of the injection molding device and multiple branch pipes respectively connected to the main pipe. Among them, the ends of the multiple branch pipes away from the main pipe correspond to the positions of multiple injection cavities and can inject glue into the corresponding injection cavities.

8. An injection mold for a worm gear transmission component according to claim 1, characterized in that, It also includes a demolding assembly disposed on the lower mold and / or the upper mold.

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