A stepped bar forming die that reduces machining allowance

Abstract

The utility model relates to mould technical field discloses a kind of step bar forming moulds of reducing machining allowance, including fixed mould and the movable mould matched with fixed mould, further include: movable mould core, dismounting connection in movable mould;Fixed mould core, dismounting connection in fixed mould, first profiling cavity with ladder shape is opened on fixed mould core, second profiling cavity matched with first profiling cavity is opened on movable mould core, when mould closes, forming cavity is formed between first profiling cavity and second profiling cavity;The utility model is provided with forming cavity with ladder structure on mould, blank obtained after injection molding is similar to finished product, on the one hand, reduce processing length, improve processing efficiency, and reduce the waste of material, on the other hand, cutting amount and processing length reduce, can reduce the heating deformation when cutting, improve workpiece machining precision.

Description

Technical Field

[0001] This utility model relates to the field of mold technology, specifically to a stepped bar forming mold that reduces machining allowance. Background Technology

[0002] Non-metallic stepped bar parts are widely found in all corners of modern industry, especially in applications requiring insulation, corrosion resistance, lightweight, self-lubrication, or biocompatibility. For example, plastic shafts are widely used in small motor shafts, printer paper feed rollers, toy drive shafts, office equipment gear shafts, and oil-free lubricated shafts in food machinery.

[0003] Existing stepped shafts are mostly machined by turning, but their blanks are usually made of equal-diameter bars. The turning process requires the removal of a large amount of blank material, which increases the processing time, reduces processing efficiency, and leads to material waste. On the other hand, plastic bars are prone to heat and deformation during long-term turning, resulting in reduced precision of the machined parts and affecting their subsequent use.

[0004] Therefore, existing technologies have shortcomings and need to be improved. Utility Model Content

[0005] This utility model provides a stepped bar forming mold that reduces machining allowance. By opening a forming cavity with an internal stepped shape on the mold, the blank approximates the shape of the finished product after the workpiece blank is formed, thus solving the problems of large cutting amount and product deformation leading to reduced precision mentioned in the background art.

[0006] This utility model provides the following technical solution:

[0007] A stepped bar forming mold for reducing machining allowance includes a fixed mold and a movable mold that matches the fixed mold, and further includes: a movable mold core, detachably connected to the movable mold; and a fixed mold core, detachably connected to the fixed mold, wherein the fixed mold core has a first contoured cavity in a stepped shape, and the movable mold core has a second contoured cavity that matches the first contoured cavity, and a forming cavity is formed between the first contoured cavity and the second contoured cavity when the mold is closed.

[0008] As a preferred technical solution of this utility model, the molding cavity includes an intermediate cavity, with a first stepped cavity at both ends of the intermediate cavity, and a second stepped cavity at the end of the first stepped cavity away from the intermediate cavity, wherein the inner diameter of the intermediate cavity is larger than the inner diameter of the first stepped cavity, and the inner diameter of the first stepped cavity is larger than the inner diameter of the second stepped cavity.

[0009] As a preferred technical solution of this utility model, the single-sided allowance range of the molding cavity in the diameter direction is 0.05-0.2mm, and the allowance range in the axial direction is 0.1-0.3mm.

[0010] As a preferred technical solution of this utility model, both the fixed mold and the moving mold are provided with mounting grooves, and the fixed mold core and the moving mold core are respectively connected to the mounting grooves by bolts.

[0011] As a preferred technical solution of this utility model, a stepped positioning pin is installed in the mounting groove, a first positioning hole is opened in the inner wall of the mounting groove, and a second positioning hole is opened on both the fixed mold core and the moving mold core. The large end of the positioning pin is slidably connected in the first positioning hole, and the small end of the positioning pin is slidably connected in the second positioning hole.

[0012] As a preferred embodiment of this utility model, the moving mold has multiple guide rods fixedly connected to it, the fixed mold has guide holes, and the guide rods are slidably connected to the guide holes.

[0013] As a preferred technical solution of this utility model, the fixed mold is provided with an injection channel, one end of which is connected to the molding cavity for injecting molten material into the molding cavity.

[0014] As a preferred technical solution of this utility model, water inlet pipes and water outlet pipes are detachably connected inside both the fixed mold core and the moving mold core. Both the fixed mold and the moving mold are provided with clearance grooves, and the water inlet pipes and water outlet pipes respectively pass through the clearance grooves.

[0015] Compared with the prior art, this utility model provides a stepped bar forming mold that reduces machining allowance, and has the following beneficial effects:

[0016] 1. In this stepped bar molding die that reduces machining allowance, a molding cavity similar to the shape of the workpiece is set on the mold. The molding cavity has a stepped structure. The blank obtained after injection molding only needs simple and minimal turning to obtain the finished product. On the one hand, it reduces the processing time and improves the processing efficiency, and also reduces material waste. On the other hand, the reduction in cutting amount and processing time can reduce heat deformation during cutting and improve the machining accuracy of the workpiece.

[0017] 2. In this stepped bar forming mold that reduces machining allowance, the fixed mold core and the moving mold core can be flexibly assembled and disassembled by using bolts, which facilitates subsequent replacement or maintenance and improves the performance.

[0018] The parts not covered in this device are the same as or can be implemented using existing technologies. This utility model sets a molding cavity with a stepped structure on the mold. The blank obtained after injection molding is similar to the finished product. On the one hand, it reduces the processing time and improves the processing efficiency, and also reduces material waste. On the other hand, the reduction of cutting amount and processing time can reduce heat deformation during cutting and improve the processing accuracy of the workpiece. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] The structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the implementation conditions of this utility model. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and purposes that this utility model can produce, should still fall within the scope of the technical content disclosed in this utility model.

[0021] Figure 1 This is a first-person perspective perspective view of the present invention.

[0022] Figure 2 This is a two-dimensional perspective view of the present invention.

[0023] Figure 3 This is a three-dimensional schematic diagram of the mold for this utility model;

[0024] Figure 4 This is a schematic diagram of the mold of this utility model.

[0025] In the diagram: 1. Fixed mold; 101. Guide hole; 102. Injection channel; 103. Mounting groove; 104. Clearance groove; 2. Moving mold; 201. Guide rod; 3. Fixed mold core; 301. First contouring cavity; 4. Moving mold core; 401. Second contouring cavity. Detailed Implementation

[0026] To make the utility model's objectives, features, and advantages more apparent and understandable, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below 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 skilled in the art without creative effort are within the scope of protection of the present utility model.

[0027] In the description of this utility model, it should be understood that the terms "upper," "lower," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. It should be noted that when a component is considered to be "connected" to another component, it can be directly connected to the other component or there may be a component centrally located at the same time.

[0028] The technical solution of this utility model will be further described below with reference to the accompanying drawings and specific embodiments.

[0029] Reference Figures 1-4 A stepped bar forming mold for reducing machining allowance includes a fixed mold 1 and a movable mold 2 that matches the fixed mold 1. Multiple guide rods 201 are fixedly connected to the movable mold 2. The guide rods 201 are provided in two to eight, preferably four. The fixed mold 1 is provided with guide holes 101 corresponding to the guide rods 201. The guide rods 201 are slidably connected to the guide holes 101 to ensure reliable sliding between the movable mold 2 and the fixed mold 1. It also includes: a moving mold core 4, which is detachably connected to the moving mold 2; and a fixed mold core 3, which is detachably connected to the fixed mold 1. The fixed mold core 3 has a first contour cavity 301 in a stepped shape, and the moving mold core 4 has a second contour cavity 401 that matches the first contour cavity 301. When the mold is closed, a forming cavity is formed between the first contour cavity 301 and the second contour cavity 401. The formed blank is similar to the stepped finished product. In the subsequent turning process, it can reduce the machining allowance, help improve the machining cycle, and reduce material waste. In addition, the reduction of cutting amount and machining time can reduce heat deformation during cutting and improve the machining accuracy of the workpiece.

[0030] When in use, by setting a molding cavity on the mold that is similar in shape to the workpiece, and the molding cavity has a stepped structure, the blank obtained after injection molding only needs simple and minimal turning to obtain the finished product. On the one hand, it reduces processing time and improves processing efficiency, and also reduces material waste. On the other hand, the reduction in cutting amount and processing time can reduce heat deformation during cutting and improve the machining accuracy of the workpiece.

[0031] Reference Figure 3 and Figure 4Here, the molding cavity includes an intermediate cavity, with a first stepped cavity at each end of the intermediate cavity, and a second stepped cavity at the end of the first stepped cavity away from the intermediate cavity. The inner diameter of the intermediate cavity is larger than the inner diameter of the first stepped cavity, and the inner diameter of the first stepped cavity is larger than the inner diameter of the second stepped cavity. The axes of the intermediate cavity, the first stepped cavity, and the second stepped cavity coincide. In addition, a first fillet is fixed on the mating surface of the first stepped cavity and the intermediate cavity. Similarly, a second fillet is fixed on the mating surface of the second stepped cavity and the first stepped cavity. A third fillet is fixed at the edge of the end face of the intermediate cavity, the end face of the first stepped cavity, and the end face of the second stepped cavity. This facilitates demolding and improves processing efficiency. The first and second fillets are both R3, and the third fillet is both R1.5.

[0032] In addition, the single-sided allowance of the forming cavity in the diameter direction is 0.05-0.2mm, preferably 0.1mm, and the allowance in the axial direction is 0.1-0.3mm, preferably 0.2mm, which can provide machining allowance for subsequent turning operations and improve the performance.

[0033] Mounting slots 103 are provided on both the fixed mold 1 and the moving mold 2. The fixed mold core 3 and the moving mold core 4 are respectively connected to the mounting slots 103 by bolts. By using bolts for disassembly, the fixed mold core 3 and the moving mold core 4 can be flexibly assembled and disassembled, facilitating subsequent replacement or maintenance and improving the performance. Furthermore, a stepped positioning pin is installed in the mounting slot 103. A first positioning hole is provided on the inner wall of the mounting slot 103, preferably two of them. A second positioning hole is provided on both the fixed mold core 3 and the moving mold core 4, and similarly, two of them are provided. The large end of the positioning pin is slidably connected to the first positioning hole, and the small end of the positioning pin is slidably connected to the second positioning hole. In use, by installing both the fixed mold core 3 and the moving mold core 4 in the mounting slots 103 using positioning pins, the installation accuracy can be improved, ensuring the accuracy of the molding cavity.

[0034] An injection channel 102 is provided on the fixed mold 1. One end of the injection channel 102 is connected to the molding cavity for injecting molten material into the molding cavity. After the fixed mold 1 is installed on the injection molding machine, the injection port on the injection molding machine is connected to the injection channel 102. After the mold is closed, molten material can be injected into the molding cavity. After the material in the molding cavity cools down, the mold can be opened to obtain the blank.

[0035] Water inlet and outlet pipes are detachably connected within both the fixed mold core 3 and the moving mold core 4. Cooling channels are provided within both the fixed mold core 3 and the moving mold core 4. The cooling channels are existing technology. One end of the water inlet and outlet pipes is threaded to both ends of the cooling channels, and both the water inlet and outlet pipes are copper pipes. Explosion-proof hoses are threaded to the ends of the water inlet and outlet pipes that extend out of the mold, especially the moving mold 2, to facilitate its movement. Circumvention grooves 104 are provided on both the fixed mold 1 and the moving mold 2, through which the water inlet and outlet pipes pass. In use, by directly connecting the water inlet and outlet pipes to the moving mold core 3 and the fixed mold core 4, leakage caused by poor sealing at the mold core and mold junction can be avoided, and the need for cooling pipes between the mold core and mold core can be eliminated, improving the performance.

[0036] Components not described in detail in this article are existing technologies.

[0037] The above-described embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A stepped bar forming die for reducing machining allowance, comprising a fixed die (1) and a movable die (2) matching the fixed die (1), characterized in that, Also includes: The moving mold core (4) is detached and connected inside the moving mold (2); The fixed mold core (3) is detached and connected inside the fixed mold (1). The fixed mold core (3) has a first contour cavity (301) in a stepped shape, and the moving mold core (4) has a second contour cavity (401) that matches the first contour cavity (301). When the mold is closed, a forming cavity is formed between the first contour cavity (301) and the second contour cavity (401).

2. The stepped bar forming mold for reducing machining allowance according to claim 1, characterized in that, The molding cavity includes an intermediate cavity, with a first stepped cavity at both ends of the intermediate cavity, and a second stepped cavity at the end of the first stepped cavity away from the intermediate cavity. The inner diameter of the intermediate cavity is larger than the inner diameter of the first stepped cavity, and the inner diameter of the first stepped cavity is larger than the inner diameter of the second stepped cavity.

3. The stepped bar forming mold for reducing machining allowance according to claim 2, characterized in that, The allowance range for the molding cavity in the diameter direction is 0.05-0.2mm, and the allowance range in the axial direction is 0.1-0.3mm.

4. The stepped bar forming mold for reducing machining allowance according to claim 1, characterized in that, Both the fixed mold (1) and the moving mold (2) are provided with mounting grooves (103), and the fixed mold core (3) and the moving mold core (4) are respectively connected to the mounting grooves (103) by bolts.

5. The stepped bar forming mold for reducing machining allowance according to claim 4, characterized in that, The mounting groove (103) is equipped with a stepped positioning pin. The inner wall of the mounting groove (103) is provided with a first positioning hole. The fixed mold core (3) and the moving mold core (4) are both provided with a second positioning hole. The large end of the positioning pin is slidably connected in the first positioning hole, and the small end of the positioning pin is slidably connected in the second positioning hole.

6. The stepped bar forming mold for reducing machining allowance according to claim 1, characterized in that, Multiple guide rods (201) are fixedly connected to the moving mold (2), and a guide hole (101) is provided on the fixed mold (1). The guide rods (201) are slidably connected to the guide hole (101).

7. The stepped bar forming mold for reducing machining allowance according to claim 1, characterized in that, The fixed mold (1) is provided with an injection channel (102), one end of which is connected to the molding cavity and is used to inject molten material into the molding cavity.

8. The stepped bar forming mold for reducing machining allowance according to claim 1, characterized in that, The fixed mold core (3) and the moving mold core (4) are both connected to a water inlet pipe and a water outlet pipe. Both the fixed mold (1) and the moving mold (2) are provided with a clearance groove (104). The water inlet pipe and the water outlet pipe pass through the clearance groove (104) respectively.

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