Roll forming die

Abstract

The utility model discloses a kind of roller forming die, it is related to powder metallurgy technical field, including middle die, upper punch mechanism and lower punch mechanism, upper punch mechanism and lower punch mechanism are located at the both sides of middle die respectively, upper punch mechanism is equipped with first upper punch and second upper punch, and second upper punch is used for the first groove of forming workpiece;Lower punch mechanism includes first lower punch, second lower punch and third lower punch, and second lower punch is used for the second groove of forming workpiece. First groove and second groove of forming workpiece are shaped by second upper punch and second lower punch respectively, subsequent machining is exempted, processing allowance is reduced, and the consumption of material is reduced. When pressing, third lower punch can push first lower punch to move in the direction of approaching middle die, the depth of first lower punch inserted in middle die can be adjusted, so as to adjust the density value when forming workpiece, realize the density difference of control workpiece both ends, avoid workpiece sintering and produce deformation or size exceeds size tolerance, it is favorable to promote assembly accuracy.

Description

Technical Field

[0001] This utility model relates to the field of powder metallurgy technology, and in particular to a roller forming mold. Background Technology

[0002] In related technologies, for rollers in compressor parts, due to their high dimensional accuracy requirements and sharp structures, traditional molds are difficult to form directly. Therefore, machining is required after forming. However, the machining allowance is large during the subsequent machining process, which not only prolongs the machining time and aggravates tool wear, but also results in low material utilization and high production costs.

[0003] At the same time, because the rollers have some thin-walled characteristics, when manufactured using powder metallurgy, the shrinkage rate of the sintering process is relatively large, and the forming process is prone to obvious uneven density distribution problems, which in turn leads to severe deformation after sintering, and the dimensions exceed the dimensional tolerances, affecting the assembly accuracy. Utility Model Content

[0004] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes a roller forming mold that reduces machining allowance, decreases the density difference of parts, and improves assembly accuracy.

[0005] A roller forming die according to an embodiment of the present invention includes: The device includes a middle die, an upper punch mechanism, and a lower punch mechanism. The upper punch mechanism and the lower punch mechanism are located on both sides of the middle die. The upper punch mechanism is equipped with a first upper punch and a second upper punch. The second upper punch is used to form the first groove of the workpiece. The lower punch mechanism includes a first lower punch, a second lower punch, and a third lower punch. The second lower punch is used to form the second groove of the workpiece. During pressing, the third lower punch can push the first lower punch to move closer to the middle die.

[0006] A roller forming die according to an embodiment of the present invention has at least the following beneficial effects: This embodiment includes a middle die, an upper punch mechanism, and a lower punch mechanism. The upper and lower punch mechanisms are located on opposite sides of the middle die. The upper punch mechanism has a first upper punch and a second upper punch, with the second upper punch forming the first groove of the workpiece. The lower punch mechanism includes a first lower punch, a second lower punch, and a third lower punch, with the second lower punch forming the second groove of the workpiece. By forming the first and second grooves of the workpiece using the second upper punch and the second lower punch respectively, subsequent machining is eliminated, machining allowance is reduced, and material consumption is reduced, improving processing efficiency while reducing material costs. During pressing, the third lower punch can push the first lower punch closer to the middle die, adjusting the insertion depth of the first lower punch into the middle die, thereby adjusting the density value of the workpiece during forming. This controls the density difference between the two ends of the workpiece, preventing deformation or exceeding dimensional tolerances during sintering, thus ensuring good assembly accuracy after workpiece forming.

[0007] According to some embodiments of the present invention, a first upper punch is sleeved on the outer periphery of a second upper punch, and a first lower punch is sleeved on the outer periphery of a second lower punch.

[0008] According to some embodiments of the present invention, the workpiece includes a first end and a second end. The first end is provided with a first groove, and the second end is provided with a second groove. Both the first groove and the second groove penetrate the workpiece radially, and the length directions of the first groove and the second groove are perpendicular to each other.

[0009] According to some embodiments of the present invention, the end of the third lower punch can abut against the end of the first lower punch away from the middle mold.

[0010] According to some embodiments of the present invention, the third lower punch is sleeved on the outer periphery of the second lower punch.

[0011] According to some embodiments of the present invention, a first upper punch plate is provided at one end of the first upper punch away from the middle mold, and the first upper punch plate can push the first upper punch to be inserted into the middle mold.

[0012] According to some embodiments of the present invention, a second upper punch plate is provided at one end of the second upper punch away from the middle mold, and the second upper punch plate can push the second upper punch to be inserted into the middle mold.

[0013] According to some embodiments of the present invention, a first lower punch plate is provided at one end of the first lower punch away from the middle mold, and the first lower punch plate can push the first lower punch to be inserted into the middle mold.

[0014] According to some embodiments of the present invention, a second lower punch plate is provided at one end of the second lower punch away from the middle mold, and the second lower punch plate can push the second lower punch to be inserted into the middle mold.

[0015] According to some embodiments of the present invention, a third lower punch plate is provided at the end of the third lower punch away from the middle mold, and the third lower punch plate can push the third lower punch to move closer to the middle mold.

[0016] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0017] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein: Figure 1 This is a cross-sectional view of a roller forming mold in an embodiment of the present utility model; Figure 2 for Figure 1 A magnified view of A in the middle; Figure 3 This is an isometric view of the workpiece in an embodiment of this utility model.

[0018] Figure label: Medium mold 100; Upper punch mechanism 110; first upper punch 111; second upper punch 112; first upper punch plate 113; second upper punch plate 114; Lower punch mechanism 120; first lower punch 121; second lower punch 122; third lower punch 123; first lower punch plate 124; second lower punch plate 125; third lower punch plate 126; Workpiece 130; First groove 131; Second groove 132; First end 133; Second end 134; Side wing 135. Detailed Implementation

[0019] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0020] In the description of this utility model, it should be understood that the directional descriptions, such as up, down, front, back, left, right, etc., indicate the directional or positional relationship based on the directional or positional relationship shown in the accompanying drawings. They 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. Therefore, they should not be construed as limitations on this utility model.

[0021] In the description of this utility model, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. If "first" or "second" is used in the description, it is only for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0022] In the description of this utility model, unless otherwise explicitly defined, terms such as "setting," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.

[0023] Reference Figures 1 to 3 A roller forming die according to an embodiment of the present invention includes a middle die 100, an upper punch mechanism 110, and a lower punch mechanism 120. The upper punch mechanism 110 and the lower punch mechanism 120 are respectively located on both sides of the middle die 100. The upper punch mechanism 110 is provided with a first upper punch 111 and a second upper punch 112. The second upper punch 112 is used to form the first groove 131 of the workpiece 130. The lower punch mechanism 120 includes a first lower punch 121, a second lower punch 122, and a third lower punch 123. The second lower punch 122 is used to form the second groove 132 of the workpiece 130. By forming the first groove 131 and the second groove 132 of the workpiece 130 by the second upper punch 112 and the second lower punch 122 respectively, subsequent machining is eliminated, machining allowance is reduced, material consumption is reduced, and processing efficiency is improved while material costs are reduced. During pressing, the third lower punch 123 can push the first lower punch 121 to move closer to the middle die 100, and can adjust the depth of the first lower punch 121 inserted into the middle die 100, thereby adjusting the density value of the workpiece 130 during forming, controlling the density difference between the two ends of the workpiece 130, avoiding deformation or exceeding the dimensional tolerance during sintering of the workpiece 130, and thus ensuring that the workpiece 130 has good assembly accuracy after forming.

[0024] Specifically, a through cavity is formed inside the middle die 100. The upper punch mechanism 110 is located above the middle die 100, while the lower punch mechanism 120 is correspondingly located below the middle die 100. During the powder filling and pressing process, the upper punch mechanism 110 moves downward and the lower punch mechanism 120 moves upward, together compressing the metal powder within the cavity of the middle die 100 to form a preform of a predetermined shape, i.e., the blank of the workpiece 130.

[0025] The first upper punch 111 is fitted around the outer periphery of the second upper punch 112. This nested structure allows the two punches to move axially independently or collaboratively. The second upper punch 112 is used to directly form the first groove 131 of the workpiece 130 on the powder compact. To drive the movement of the upper punches, a first upper punch plate 113 is connected to the upper end of the first upper punch 111 away from the middle die 100, and a second upper punch plate 114 is connected to the upper end of the second upper punch 112 away from the middle die 100. The first upper punch plate 113 and the second upper punch plate 114 are typically driven by an external press, which transmits pressure to the first upper punch 111 and the second upper punch 112 respectively, controlling the depth and timing of their insertion into the cavity of the middle die 100.

[0026] Similar to the upper punch mechanism 110, the lower punch mechanism 120 also adopts a nested structure. A first lower punch 121 is fitted around the outer periphery of a second lower punch 122. The top shape of the second lower punch 122 corresponds to the second groove 132 of the workpiece 130. A third lower punch 123 is also fitted around the outer periphery of the second lower punch 122, positioned below the first lower punch 121. To provide power, the first lower punch 121 is connected to a first lower punch plate 124, the second lower punch 122 is connected to a second lower punch plate 125, and the third lower punch 123 is connected to a third lower punch plate 126. These lower punches are controlled by a drive device at the bottom of the press, enabling precise pushing of their respective connected lower punches upwards into the cavity of the intermediate die 100, or resetting them.

[0027] Reference Figure 3 The workpiece 130 has a cylindrical body. A first groove 131 is formed at its first end 133, and a second groove 132 is formed at its second end 134. Both grooves 131 and 132 completely penetrate the radial direction of the workpiece 130, resulting in a thin-walled outer surface, i.e., side wings 135, which increases the difficulty of forming and sintering. More importantly, the first groove 131 and the second groove 132 are not spatially aligned; their length directions are perpendicular to each other, i.e., they are offset by 90 degrees. This structure allows the workpiece 130 to meet specific transmission or positioning requirements during assembly, but it also places higher demands on the mold. During pressing, the powder flow resistance is high, which can easily lead to different densities of the side wings 135 at the first end 133 and the second end 134, resulting in deformation or dimensional deviations beyond tolerance after sintering, thus causing insufficient assembly accuracy.

[0028] To address the aforementioned issues, in this embodiment, firstly, during the powder loading stage, the upper punch mechanism 110 is raised as a whole, moving away from the upper surface of the intermediate mold 100, while the first lower punch 121 and the second lower punch 122 of the lower punch mechanism 120 are inserted into the intermediate mold 100 and positioned in a preset initial position. At this time, the top surfaces of the first lower punch 121 and the second lower punch 122 together form the bottom of the cavity of the intermediate mold 100. The powder feeder fills a fixed amount of metal powder into the cavity of the intermediate mold 100. Subsequently, the upper punch mechanism 110 begins to move downward under the action of the press. The first upper punch 111 and the second upper punch 112 simultaneously contact the powder and apply pressure. Meanwhile, the lower punch mechanism 120 is not stationary but undergoes precise coordinated movement. Driven by the third lower punch plate 126, the third lower punch 123 moves upward, its end directly abutting against and pushing the first lower punch 121 away from the lower end of the middle die 100. This provides the first lower punch 121 with an additional upward assist, creating a "bidirectional pressing" effect with the upper punch mechanism 110. This results in the powder being subjected to pressure from both above and below in the vertical direction, greatly improving the powder compression of the pressed blank, especially in the area of ​​the second end 134 of the workpiece 130. This effectively reduces the density gradient of the pressed blank in the axial direction, thereby reducing the density difference between the side wings 135 at both ends of the workpiece 130. At the end of the pressing stroke, the end of the second upper punch 112 is completely pressed into the powder, forming the first groove 131 at the top of the workpiece 130. Similarly, the end of the second lower punch 122 also moves upward to a predetermined position, forming the second groove 132 at the bottom of the workpiece 130.

[0029] In the final demolding stage, the upper punch mechanism 110 is first lifted, and the first upper punch 111 and the second upper punch 112 sequentially detach from the upper end of the formed blank and exit the cavity of the middle die 100. Subsequently, the lower punch mechanism 120 begins the ejection action. The first lower punch 124, the second lower punch 125, and the third lower punch 126 are usually driven synchronously, pushing the first lower punch 121, the second lower punch 122, and the third lower punch 123 to move upward together, completely ejecting the workpiece 130 that is firmly wrapped in the cavity of the middle die 100.

[0030] The embodiments of the present utility model have been described in detail above with reference to the accompanying drawings. However, the present utility model is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present utility model.

Claims

1. A roller forming die for forming workpieces, characterized in that, include: The device comprises a middle die, an upper punch mechanism, and a lower punch mechanism. The upper punch mechanism and the lower punch mechanism are located on opposite sides of the middle die. The upper punch mechanism has a first upper punch and a second upper punch. The second upper punch is used to form a first groove in the workpiece. The lower punch mechanism includes a first lower punch, a second lower punch, and a third lower punch. The second lower punch is used to form a second groove in the workpiece. During pressing, the third lower punch can push the first lower punch to move closer to the middle die.

2. The roller forming die according to claim 1, characterized in that, The first upper punch is sleeved on the outer periphery of the second upper punch, and the first lower punch is sleeved on the outer periphery of the second lower punch.

3. The roller forming die according to claim 1, characterized in that, The workpiece includes a first end and a second end. The first end is provided with a first groove, and the second end is provided with a second groove. Both the first groove and the second groove penetrate the workpiece radially, and their length directions are perpendicular to each other.

4. The roller forming die according to claim 1, characterized in that, The end of the third lower punch can abut against the end of the first lower punch that is away from the middle die.

5. A roller forming die according to claim 1, characterized in that, The third lower punch is sleeved on the outer periphery of the second lower punch.

6. The roller forming die according to claim 1, characterized in that, The first upper punch has a first upper punch plate at the end opposite to the middle mold, and the first upper punch plate can push the first upper punch to be inserted into the middle mold.

7. A roller forming die according to claim 1, characterized in that, The second upper punch has a second upper punch plate at one end away from the middle mold, and the second upper punch plate can push the second upper punch to be inserted into the middle mold.

8. A roller forming die according to claim 1, characterized in that, The first lower punch has a first lower punch plate at the end opposite to the middle mold, and the first lower punch plate can push the first lower punch to be inserted into the middle mold.

9. A roller forming die according to claim 1, characterized in that, The second lower punch has a second lower punch plate at one end away from the middle mold, and the second lower punch plate can push the second lower punch to be inserted into the middle mold.

10. A roller forming die according to claim 1, characterized in that, The third lower punch has a third lower punch plate at the end opposite to the middle mold, and the third lower punch plate can push the third lower punch to move closer to the middle mold.

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