Retreating mechanism and method for multi-weight negative angle stamping part

Abstract

The invention discloses a rollback mechanism and rollback method for a multi-weight negative angle stamping part, and the rollback mechanism comprises a material pressing plate which is connected with an upper die base through a first elastic element; the forming male dies are fixedly arranged on the upper die base; the forming female dies are arranged on the lower die base in a sliding mode; the number of the forming male dies and the number of the forming female dies correspond to the number of negative angles of parts. The lower die base is provided with sliding slopes corresponding to the forming female dies, and the forming female dies are driven by second elastic elements to slide along the corresponding sliding slopes. The material lifting plate drives the part to move in the vertical direction through a third elastic element; the second elastic element and the third elastic element are fixedly arranged on the lower die holder; the bounce of the first elastic element, the bounce of the third elastic element and the bounce of the second elastic element are sequentially reduced. According to the invention, the back-off action of the forming female die after multiple negative angle stamping forming of a part can be completed in a one-time stamping cycle process, and the size quality of the part is more stable.

Description

Technical Field

[0001] The present invention relates to the technical field of punching processing of parts with multiple negative angles, and more specifically, to a retraction mechanism and a retraction method for punching parts with multiple negative angles. Background Art

[0002] There are many ways to save energy and reduce emissions in automobiles, and lightweighting of the body is an important way. In the automotive industry, the main approach is to reduce weight through structure. On the premise of meeting the body function, more and more stamping parts are combined into one part through geometric topology optimization to reduce the number of parts, reduce the number of welding points, reduce the weight of the body, simplify the manufacturing process and shorten the manufacturing time, thereby improving the competitiveness of the company's products. However, the problem that follows the merging of the parts themselves is that the spatial complexity of the parts increases, resulting in an increase in the process steps of mold manufacturing, a complex mold structure, and a decrease in the utilization rate of part materials. On the premise of ensuring product stability and quality, reducing the mold process steps is an effective way to reduce the cost of mold development and manufacturing. The core of reducing the number of mold process steps is to design a compact and stable mold structure for efficient stamping production. Conventional stamping parts generally avoid stamping negative angles in the initial design, or try to reduce the stamping negative angle area as much as possible to ensure the feasibility of the mold structure and ensure that the mold can smoothly perform side shaping on the stamping negative angle area. In recent years, more and more stamping sub-parts have been merged into one part by multiple parts, and the parts themselves have multiple stamping negative angles, and there are two or more negative angle areas in the part's own cavity. This undoubtedly brings great challenges and opportunities to the development of stamping dies. Therefore, it is necessary to develop a compact stamping negative angle retraction mechanism to effectively solve the above problems. Summary of the invention

[0003] An object of the present invention is to solve at least the above problems and to provide at least the advantages which will be described hereinafter.

[0004] In order to achieve these purposes and other advantages according to the present invention, a retraction mechanism for multiple negative angle stamping parts is provided, which is arranged on a stamping die, wherein the stamping die includes an upper die seat and a lower die seat, and the retraction mechanism includes: A pressing plate connected to the upper die seat via a first elastic element; A plurality of forming convex dies fixedly arranged on the upper die seat; A plurality of forming dies are respectively slidably arranged on the lower die seat; the number of the forming convex dies and the forming dies corresponds to the number of negative angles of the parts; a sliding inclined surface is arranged on the lower die seat corresponding to each of the forming dies, and each of the forming dies slides along the corresponding sliding inclined surface respectively driven by the second elastic element; A material lifting plate connected to the part through a material belt; the material lifting plate drives the part to move in a vertical direction through a third elastic element; the second elastic element and the third elastic element are both fixedly arranged on the lower die base; The rebound forces of the first elastic element, the third elastic element and the second elastic element decrease in sequence.

[0005] Preferably, each sliding inclined surface is provided with a dovetail groove, and a sliding block matching with the dovetail groove is provided on the bottom surface of each molding die sliding along the sliding inclined surface.

[0006] Preferably, the second elastic element is arranged parallel to the sliding inclined surface, a connecting block is arranged at the bottom of the sliding block of the forming die, a receiving groove is arranged at the bottom surface of the dovetail groove corresponding to the connecting block, and the second elastic element is fixedly arranged in the receiving groove.

[0007] Preferably, the lower end of each sliding inclined surface corresponds to the negative angle of the part, and the higher end is close to the center of the part.

[0008] Preferably, a lubricating oil groove is provided on the side or bottom surface of the dovetail groove.

[0009] Preferably, the first elastic element is vertically arranged, one end of which is fixedly connected to the upper die base, and the other end of which is fixedly connected to the pressing plate; the pressing plate abuts against the part under the action of the first elastic element.

[0010] Another object of the present invention is to provide a retraction method for multiple negative angle stamping parts, using the retraction mechanism, comprising the following steps: S1, the punch press drives the upper die seat downward, and during the closing process of the stamping die, the second elastic element, the third elastic element and the first elastic element are compressed in sequence, and each forming convex die and the corresponding forming concave die jointly apply pressure to the part to complete multiple negative angle stamping forming; S2. The punch press drives the upper die seat upward. As the stamping die opens, the first elastic element, the third elastic element and the second elastic element release their strokes in sequence. Finally, each forming die leaves the negative angle area of ​​the part under the action of the second elastic element, and the part is separated from each forming die under the action of the third elastic element.

[0011] Preferably, step S2 specifically includes the following steps: S21, as the upper die holder moves upward, the stroke of the first elastic element begins to be released first, during which the forming punch leaves the part along with the upper die holder, and the pressing plate, the part, the lifting plate and each forming die remain stationary; S22, during the continuous upward movement of the upper die holder, after the stroke release of the first elastic element is completed, the strokes of the second elastic element and the third elastic element begin to be released synchronously, each forming die moves up along the sliding slope, and the parts move up synchronously under the action of the lifting plate; S23, when the upward stroke of the upper die seat is completed, the pressure plate is separated from the part, and after the stroke release of the second elastic unit is completed, each of the forming dies stops moving and has left the negative angle area of ​​the part; the stroke of the third elastic element lags behind the release completion of the second elastic element, and then the part continues to be lifted upward until it is completely separated from each forming die.

[0012] The present invention has at least the following beneficial effects: The retraction mechanism and retraction method for multiple negative angle stamping parts provided by the present invention can complete multiple negative angle stamping forming of parts in one stamping cycle. After forming, the forming die and parts in the negative angle area can smoothly complete the negative angle retraction action in a pre-set sequence of movement. Compared with the traditional side-forming inclined wedge mechanism, it has the advantages of compact spatial structure, precise stroke control, and low manufacturing cost. In addition, completing multiple negative angle stampings in one stamping process can obtain parts with more stable and consistent dimensional quality, improve the production SPM value (the number of parts that the mold can cut per unit time), and reduce the mold development cost.

[0013] Other advantages, objectives and features of the present invention will be embodied in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic structural diagram of the retraction mechanism for multiple negative angle stamping parts according to the present invention when the stamping die is closed; Figure 2 It is a vertical cross-sectional view of the retracting mechanism for multiple negative angle stamping parts of the present invention when the first elastic element has completed the stroke release; Figure 3 It is a schematic structural diagram of the retracting mechanism for multiple negative angle stamping parts according to the present invention when the second elastic element has completed the stroke release; Figure 4 It is a schematic structural diagram of the retraction mechanism for multiple negative angle stamping parts according to the present invention when the third elastic element has completed the stroke release; Figure 5 A schematic diagram of the structure of one of the forming concave dies of the present invention; DETAILED DESCRIPTION

[0015] The present invention is further described in detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0016] It should be noted that the experimental methods described in the following embodiments are conventional methods unless otherwise specified, and the reagents and materials are commercially available unless otherwise specified; in the description of the present invention, the terms "lateral", "longitudinal", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0017] like Figures 1 to 4 As shown, the present invention provides a retraction mechanism for multiple negative angle stamping parts, which is arranged on a stamping die, wherein the stamping die includes an upper die seat 5 and a lower die seat 1, and the retraction mechanism includes: A pressing plate 4, which is connected to the upper die base 5 via a first elastic element 9; A plurality of forming convex dies 3 fixedly arranged on the upper die seat; A plurality of forming dies 2 are respectively slidably arranged on the lower die base 1; the number of the forming convex dies 3 and the forming dies 2 corresponds to the number of negative angles of the part 7; a sliding inclined surface 11 is arranged on the lower die base 1 corresponding to each of the forming dies 2, and each of the forming dies 2 slides along the corresponding sliding inclined surface 11 respectively driven by the second elastic element 8; A material lifting plate 6, which is connected to the part 7 through a material belt; the material lifting plate 6 drives the part 7 to move in the vertical direction through a third elastic element; the second elastic element 8 and the third elastic element are both fixedly arranged on the lower die base 1; The rebound forces of the first elastic element 9 , the third elastic element and the second elastic element 8 decrease in sequence.

[0018] In this technical solution, during the closing process of the stamping die, the second elastic element 8, the third elastic element and the first elastic element 9 are compressed in sequence, and multiple negative angle forming of the part is completed under the interaction of each of the forming convex dies 3 and the corresponding forming concave dies 2. When the stamping die is opened, the first elastic element 9 first releases the stroke as the upper die seat 5 moves upward. The release stroke described here is the process in which the elastic element recovers its initial length during the process in which the external force compressing each elastic element gradually disappears. As the stamping die is opened, each of the forming concave dies 2 slides along the sliding slope 11 under the action of the corresponding second elastic element 8. At the same time, when the third elastic element releases the stroke, the part 7 is driven upward by the lifting plate 6. When the pressing plate 4 is separated from the part, the part 7 and each of the forming concave dies 6 are also separated from each other, and the part can be moved to the next process without contact interference. The first elastic element 9, the third elastic element and the second elastic element 8 can all adopt the return springs conventionally used in the stamping field. The retraction mechanism can complete the forming of multiple negative angles of the parts in one stamping cycle, and the negative angle area after forming can smoothly complete the negative angle retraction action according to the pre-set sequence of movements. In addition, completing multiple negative angles in one stamping process can obtain parts with more stable and consistent dimensional quality, improve the production SPM value (the number of parts that the mold can cut per unit time), and reduce the mold development cost.

[0019] In another technical solution, each sliding inclined surface 11 is provided with a dovetail groove 10, and each of the molding dies 2 is provided with a slider 21 matching the dovetail groove 10 on the bottom surface along which the molding dies 2 slide along the sliding inclined surface 11. The sliding of the molding dies 2 along the sliding inclined surface 11 is guided by the dovetail groove 10, so that the sliding process is more stable.

[0020] Furthermore, a lubricating oil groove is provided on the side or bottom surface of the dovetail groove 10 to ensure smoothness of the sliding of the forming die 2 .

[0021] In another technical solution, referring to Figure 5, the second elastic element 8 is arranged parallel to the sliding inclined surface 11, a connecting block 22 is arranged at the bottom of the slider 21 of the forming die 2, and a receiving groove is arranged on the bottom surface of the dovetail groove 10 corresponding to the connecting block 22, and the second elastic element 8 is fixedly arranged in the receiving groove. One end of the second elastic element 8 is fixedly connected to the bottom surface of the receiving groove, and the other end passes through the connecting block 22 to connect to the slider 21, or is directly connected to the connecting block 22; the connecting block 22 is also located in the receiving groove. By arranging the second elastic element 8 in parallel with the sliding inclined surface 11, the stroke release direction and the rebound force direction of the second elastic element 8 are parallel to the sliding inclined surface 11, so that the forming die 2 can be driven to slide along the sliding inclined surface 11 stably and accurately. At the same time, the second elastic element 8 is arranged in the receiving groove, which also makes the entire mold structure more compact, and is more suitable for working conditions with small crotch space in multiple negative angle areas of parts.

[0022] In another technical solution, the lower end of each sliding slope 11 corresponds to the negative angle of the part 9, and the higher end is close to the center of the part 7. That is, the inclination angle of each sliding slope 11 is inclined upward from the negative angle area to the center of the part. When the stroke of each second elastic element 8 is released, it pushes the corresponding molding die 2 from the negative angle area to the center of the part, so that the molding die 2 leaves the negative angle area to avoid contact and interference with the part during demolding.

[0023] In another technical solution, the first elastic element 9 is vertically arranged, one end of which is fixedly connected to the upper die base 5, and the other end is fixedly connected to the pressing plate 2; the pressing plate 2 abuts against the part 7 under the action of the first elastic element 9. The pressing plate 2 is used to maintain the stability of the part 7 during the stamping and retraction process.

[0024] The present invention also provides a retraction method for multiple negative angle stamping parts, using the retraction mechanism, comprising the following steps: S1, the punch press drives the upper die seat 5 downward, and during the closing process of the stamping die, the second elastic element 8, the third elastic element and the first elastic element 9 are compressed in sequence, and each forming convex die 3 and the corresponding forming concave die 2 jointly apply pressure to the part 9 to complete multiple negative angle stamping forming, such as Figure 1 As shown; S2, the punch press drives the upper die seat 5 upward, and as the stamping die is opened, the first elastic element 9, the third elastic element and the second elastic element 8 are released in sequence, and finally each forming die 2 leaves the negative angle area of ​​the part 7 under the action of the second elastic element 8, and the part 7 is separated from each forming die 2 under the action of the third elastic element. Figure 4 shown.

[0025] In the above technical solution, when the mold is closed, the working order of the various components of the multiple stamping negative angle retraction mechanism is opposite to that when the mold is opened. Since the rebound forces of the first elastic element 9, the third elastic element and the second elastic element 8 decrease successively, in step S1, during the mold closing process, the third elastic element and the second elastic element 8 are compressed first, and the first elastic element 9 is compressed later. The mold opening process is the opposite, and step S2 specifically includes the following steps: S21, as the upper die holder 5 moves upward, the stroke of the first elastic element 9 begins to be released first. During this process, the forming punch 6 leaves the part 7 along with the upper die holder 5, and the pressing plate 4, the part 7, the lifting plate 6 and each forming die 2 remain stationary. Figure 2 As shown; during the release of the first elastic element 9, the pressing plate 4 always maintains contact with the part 7, and the contact force gradually decreases; S22, during the continuous upward movement of the upper die holder 5, after the travel of the first elastic element 9 is released, the travel of the second elastic element 8 and the third elastic element begins to be released synchronously, and each forming die 2 moves up along the sliding inclined surface 11, and the parts move up synchronously under the action of the lifting plate 6. Figure 3 As shown; S23, when the upper die holder 5 completes its upward stroke, the pressing plate 4 separates from the part 7, and after the second elastic unit 8 completes its stroke release, each of the molding dies 2 stops moving and has left the negative angle area of ​​the part 7; the rebound force of the third elastic element is greater than that of the second elastic element, so its stroke lags behind the release completion of the second elastic element 8, and then the part 8 continues to be lifted upward until it is completely separated from each molding die 2, such as Figure 4 At this time, there is no contact interference in the upward movement of each negative angle area of ​​the part 7, and it can be directly moved to the next process.

[0026] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes, and they can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and the illustrations shown and described herein.

Claims

1. A retraction mechanism for multiple negative angle stamping parts, arranged on a stamping die, wherein the stamping die comprises an upper die seat and a lower die seat, characterized in that: The rollback mechanism comprises: A pressing plate connected to the upper die seat via a first elastic element; A plurality of forming convex dies fixedly arranged on the upper die seat; A plurality of forming dies are respectively slidably arranged on the lower die seat; the number of the forming convex dies and the forming dies corresponds to the number of negative angles of the parts; a sliding inclined surface is arranged on the lower die seat corresponding to each of the forming dies, and each of the forming dies slides along the corresponding sliding inclined surface respectively driven by the second elastic element; A material lifting plate connected to the part through a material belt; the material lifting plate drives the part to move in a vertical direction through a third elastic element; the second elastic element and the third elastic element are both fixedly arranged on the lower die base; The rebound forces of the first elastic element, the third elastic element and the second elastic element decrease in sequence.

2. The retraction mechanism for multiple negative angle stamping parts according to claim 1, characterized in that: Each sliding inclined surface is provided with a dovetail groove, and a sliding block matched with the dovetail groove is provided on the bottom surface of each forming concave mold sliding along the sliding inclined surface.

3. The retraction mechanism for multiple negative angle stamping parts according to claim 2, characterized in that: The second elastic element is arranged parallel to the sliding inclined surface, a connecting block is arranged at the bottom of the sliding block of the forming die, a receiving groove is arranged at the bottom surface of the dovetail groove corresponding to the connecting block, and the second elastic element is fixedly arranged in the receiving groove.

4. The retraction mechanism for multiple negative angle stamping parts according to claim 1, characterized in that: The lower end of each sliding inclined surface corresponds to the negative angle of the part, and the higher end is close to the center of the part.

5. The retraction mechanism for multiple negative angle stamping parts according to claim 2, characterized in that: A lubricating oil groove is provided on the side surface or the bottom surface of the dovetail groove.

6. The retraction mechanism for multiple negative angle stamping parts according to claim 1, characterized in that: The first elastic element is vertically arranged, one end of which is fixedly connected to the upper die base, and the other end of which is fixedly connected to the pressing plate; the pressing plate abuts against the part under the action of the first elastic element.

7. A method for retracting a multiple negative angle stamping part, using the retracting mechanism as claimed in claim 1, characterized in that: The following steps are involved: S1, the punch press drives the upper die seat downward, and during the closing process of the stamping die, the second elastic element, the third elastic element and the first elastic element are compressed in sequence, and each forming convex die and the corresponding forming concave die jointly apply pressure to the part to complete multiple negative angle stamping forming; S2. The punch press drives the upper die seat upward. As the stamping die opens, the first elastic element, the third elastic element and the second elastic element release their strokes in sequence. Finally, each forming die leaves the negative angle area of ​​the part under the action of the second elastic element, and the part is separated from each forming die under the action of the third elastic element.

8. The method for retracting a multiple negative angle stamping part according to claim 7, characterized in that: Step S2 specifically includes the following steps: S21, as the upper die holder moves upward, the stroke of the first elastic element begins to be released first, during which the forming punch leaves the part along with the upper die holder, and the pressing plate, the part, the lifting plate and each forming die remain stationary; S22, during the continuous upward movement of the upper die holder, after the stroke release of the first elastic element is completed, the strokes of the second elastic element and the third elastic element begin to be released synchronously, each forming die moves up along the sliding slope, and the parts move up synchronously under the action of the lifting plate; S23, when the upward stroke of the upper die seat is completed, the pressure plate is separated from the part, and after the stroke release of the second elastic unit is completed, each of the forming dies stops moving and has left the negative angle area of ​​the part; the stroke of the third elastic element lags behind the release completion of the second elastic element, and then the part continues to be lifted upward until it is completely separated from each forming die.

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