Forming compound die for bent rod
By using a composite die for forming a bending rod to complete cutting, bending, and automatic demolding in a single stamping process, the low efficiency and demolding difficulties caused by multiple processes in the existing technology are solved, and high-efficiency and high-precision bending rod processing is achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- NINGBO RUYI JOINT CO LTD
- Filing Date
- 2026-04-15
- Publication Date
- 2026-05-19
AI Technical Summary
Existing bending bar processing requires multiple steps, resulting in low production efficiency, large cumulative errors, and difficulty in demolding, which increases costs and difficulty.
Design a composite mold for forming a bent bar, which completes cutting, bending and automatic demolding in one stamping process. The cutting, bending and automatic demolding are integrated by the cooperation of the elastic ejector and the guide.
It improved production efficiency and product precision, simplified process flow, and reduced energy consumption and operating costs.
Smart Images
Figure CN122057809A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the technical field of stamping dies, and specifically to a composite die for forming bent bars. Background Technology
[0002] In the field of hardware manufacturing and processing, it is often necessary to bend metal round bars or metal wires into specific shapes (such as inverted triangles, U-shapes or V-shapes). Traditional bending bar processing methods usually require two independent processes: cutting and bending, and may even require the use of multiple different molds. This not only leads to low production efficiency and increased labor or equipment handling costs, but also the repeated positioning can easily cause cumulative errors, affecting the forming accuracy of the final product.
[0003] Furthermore, in some existing bending dies, after the bar stock is bent and formed, the clamping force during material deformation often causes the formed bar to adhere tightly to the core, making demolding extremely difficult. Traditional methods that rely on manual hammering or the addition of complex pneumatic demolding mechanisms not only increase the manufacturing cost and maintenance difficulty of the mold, but also slow down the entire processing cycle. Summary of the Invention
[0004] This invention addresses the aforementioned problems and aims to provide a composite mold for forming bent bars, which enables cutting, bending, and automatic demolding to be completed in a single stamping process, thereby improving production efficiency and product precision.
[0005] To achieve the above objectives, the present invention provides a forming composite mold for bending bars, comprising a lower mold and an upper mold; The lower mold is provided with a first core, two positioning frames with guide portions located on both sides of it, and an elastic ejector. The upper die is provided with a first pressure block that is elastically connected, two second pressure blocks disposed on both sides thereon, and a punch corresponding to one of the positioning frames. Both second pressure blocks are hinged to the bottom of the upper die. The first pressing block and the first core are positioned directly opposite each other in the vertical direction; The second pressure block and the guide part have overlapping trajectories in the vertical direction to form a sliding fit; In the vertical direction, the bottom height of the punch is lower than the bottom height of the second pressure block; The elastic ejector has a clearance position and an ejection position, and the elastic ejector is configured to have a driving surface that abuts against the bottom of the upper mold to achieve switching from the ejection position to the clearance position.
[0006] According to the above-described composite mold for forming a bent bar, one of the positioning frames is a first positioning frame with a supporting top surface, and the other positioning frame is a second positioning frame with an abutting limiting surface; the punch and the inner wall surface of the first positioning frame are fitted together and offset.
[0007] According to the above-described composite mold for forming a bent bar, the lower mold is further provided with a placement frame, which is located outside the first positioning frame and has a feeding through hole. The height of the bottom of the feeding through hole is consistent with the height of the support top surface.
[0008] According to the above-described composite mold for forming a bent bar, the bottom of the upper mold is provided with two spaced mounting brackets, the bottom end of the mounting brackets is provided with mounting holes arranged in the front-back direction, and the second pressure block is provided with a rotating shaft arranged in the front-back direction, the rotating shaft being rotatably arranged in the mounting holes.
[0009] According to the above-described composite mold for forming a bent bar, the top of the first pressure block is provided with a first spring, and is suspended from the bottom of the upper mold by the first spring; The first pressure block is located between the two mounting brackets.
[0010] According to the above-described composite mold for forming a bent bar, the bottom of the upper mold is also provided with a mold base, the first pressure block, the second pressure block and the punch are all located in the mold base, and the bottom of the mold base is provided with an abutting inclined surface corresponding to the driving surface.
[0011] According to the above-described composite mold for forming a bent bar, the elastic ejector includes a slide block, an ejector rod, and a second spring. One end of the second spring is connected to the rear side of the slide block, and the other end of the second spring is connected to the lower mold along the front-rear direction. One end of the ejector rod is connected to the front side of the slide block, and the other end of the ejector rod can extend into one side of the first core to eject the formed bent bar.
[0012] According to the above-described composite mold for forming a bent bar, the driving surface is configured as a driving inclined surface, and the driving inclined surface is arranged obliquely on the top of the slide.
[0013] According to the above-described composite mold for forming a bent rod, the guide portion is a guide slope that is inclined from top to bottom toward the first core direction.
[0014] According to the above-described composite mold for forming a bent rod, in the fully closed state, the bottom surface of the first pressing block, the top surface and two sides of the first core, and the inner sides of the two rotated second pressing blocks together form an inverted triangular cavity.
[0015] This invention has the following advantages: the bottom of the punch of the upper die is lower than the second pressure block. During the die closing and pressing process, the punch first cooperates with the first positioning frame to cut the bar stock. Then the first and second pressure blocks continue to press down to complete the bending and forming. At the same time, the power of the upper die pressing down (the cooperation between the inclined surface and the driving surface) is cleverly used to force the elastic ejector to retreat to the "avoidance position" during forming, avoiding interference with the forming process. When the upper die is reset and lifted, the elastic ejector is instantly ejected to the "ejection position" under the action of the spring force, automatically ejecting the finished product that is held on the first core. The whole process does not require an additional power source. The structure is simple and highly reliable. Cutting, bending and forming and automatic demolding are integrated into the same stamping stroke, saving multiple process steps and greatly improving production efficiency. Attached Figure Description
[0016] Figure 1 This is a schematic diagram of the overall structure of the composite mold in the open / closed state according to the embodiment; Figure 2 This is a schematic diagram of the overall structure of the composite mold in the mold-closed state according to the embodiment; Figure 3 This is a schematic diagram of the lower mold structure in an embodiment; Figure 4 This is a schematic diagram of the elastic ejector structure of an embodiment; Figure 5 This is a schematic diagram of the bottom structure of the upper mold in an embodiment; Figure 6 This is a schematic diagram of the internal structure of the mold base in an embodiment.
[0017] In the picture: 100. Lower mold; 110. First core; 120. First positioning frame; 121. Guide part; 122. Support top surface; 130. Second positioning frame; 131. Abutment limiting surface; 140. Elastic ejector; 141. Slide; 141a. Drive inclined surface; 142. Ejector rod; 143. Second spring; 150. Placement frame; 151. Feed through hole; 200. Upper mold; 210. First pressure block; 211. First spring; 220. Second pressure block; 221. Rotating shaft; 230. Punch; 240. Mounting bracket; 250. Mold base; 251. Abutting slope. Detailed Implementation
[0018] The following are specific embodiments of the present invention, which are described in conjunction with the accompanying drawings. However, the invention is not limited to these embodiments.
[0019] like Figure 1-6As shown, the present invention provides a forming compound mold for bending bars, which mainly consists of two parts: a lower mold 100 and an upper mold 200. It is used to process straight bar stock into inverted triangular bent bar parts. The lower mold 100 is a fixed mold, and the upper mold 200 is a moving mold. The mold closing and opening are realized by the lifting and lowering movement of the upper mold 200. During the mold closing process, the bar stock is stamped.
[0020] Specifically, the lower die 100 is fixed on the lower worktable of the punch press. The lower die 100 is provided with a first core 110, two positioning frames, an elastic ejector 140, and a placement frame 150.
[0021] The first core 110 is located at the center of the lower mold 100. The first core 110 is the core template reference for bending and forming. It has a flat top surface and two sides that taper inward (generally with a shape that is wider at the top and narrower at the bottom). The bent rod is formed on the first core 110 and takes the shape of an inverted triangle after forming.
[0022] Two positioning frames are respectively set on the left and right sides of the first core 110. One positioning frame is a first positioning frame 120 with a supporting top surface 122, and the other positioning frame is a second positioning frame 130 with an abutment limiting surface 131. The first positioning frame 120 is used to support the bar to be processed, and the second positioning frame 130 is used to abut the end of the bar, thereby controlling the total processing length of the bar. In order to meet the processing size requirements of bending the bar, the inner side of the first positioning frame 120 and the inner side of the second positioning frame 130 are required to be flush with the first core. The distances between 110 are all the same. In order to facilitate continuous feeding of bar stock, the lower die 100 is also fixedly provided with a placement frame 150 on the outside of the first positioning frame 120. The placement frame 150 is provided with a feeding through hole 151. The height of the bottom of the feeding through hole 151 is consistent with the height of the support top surface 122 of the first positioning frame 120, so as to ensure that the bar stock can pass horizontally through the feeding through hole 151, rest steadily on the support top surface 122 and pass through the top of the first core 110 until it hits the abutment limiting surface 131 of the second positioning frame 130.
[0023] In this embodiment, both positioning frames are provided with guide portions 121, which are guide slopes that are inclined from top to bottom toward the first core 110 and are arranged in a figure-eight shape.
[0024] The elastic ejector 140 is installed on the rear side of the lower mold 100 for automatic demolding after molding. The elastic ejector 140 has a clearance position and an ejection position, and is configured to have a driving surface that abuts against the bottom of the upper mold 200 to achieve switching from the ejection position to the clearance position. In this embodiment, the ejection position of the elastic ejector 140 is its initial position. During the downward mold closing process of the upper mold 200, the elastic ejector 140 can be compressed or displaced by the contact between the upper mold 200 and the elastic ejector 140, so that it moves from the ejection position to the clearance position to avoid interfering with the molding of the bent bar. After the bent bar is formed, the upper mold 200 moves upward to open the mold. At this time, the elastic ejector 140 has an elastic restoring force, which can drive it to return to the ejection position and automatically eject the molded product without the need to arrange other ejection power units, which can reduce energy consumption and operating costs.
[0025] Furthermore, the elastic ejector 140 includes a slide 141, an ejector rod 142, and a second spring 143. The front end of the second spring 143 is connected to the rear side of the slide 141, and the rear end rests on the fixed baffle of the lower mold 100. One end of the ejector rod 142 is connected to the front side of the slide 141, and the other end can extend into one side of the first core 110 to eject the formed bent rod. In the natural state (ejection position), the second spring 143 pushes the slide 141 forward, and the ejector rod 142 extends out of the side of the first core 110. In the compressed state (avoidance position), the slide 141 overcomes the elastic force of the second spring 143 and retracts, and the ejector rod 142 retracts without interfering with the operation of the pressing block on the front. The driving surface is set as a driving inclined surface 141a and is arranged obliquely on the top of the slide 141.
[0026] Specifically, the upper mold 200 is provided with a connecting shaft at its top, which can be connected to the spindle of the machine tool. The upper mold 200 is driven to move up and down by the spindle of the machine tool. The upper mold 200 is provided with a first pressure block 210, a second pressure block 220, a punch 230, a mounting bracket 240 and a mold base 250. The first pressure block 210, the second pressure block 220, the punch 230 and the mounting bracket 240 are all installed inside the mold base 250.
[0027] The first pressing block 210 and the first core 110 are vertically aligned and face each other. The top of the first pressing block 210 is provided with a first spring 211, which suspends it from the bottom of the upper mold 200. During the mold closing process of the upper mold 200, the first pressing block 210 can descend to abut against the top of the bar stock. After the top of the first pressing block 210 and the first core 110 cooperate to clamp the middle of the bar stock, if the upper mold 200 continues to descend, the horizontal height of the first pressing block 210 will no longer change, and it will compress the first spring 211. Meanwhile, the second pressing block 220 and the punch 230 continue to descend.
[0028] In this embodiment, the bar stock is required to be cut before bending. Therefore, in the vertical direction, the bottom height of the punch 230 is required to be lower than the bottom height of the second pressure block 220. Thus, after the first pressure block 210 abuts against the bar stock, the punch 230 is required to contact the bar stock first and cut it. Then, the second pressure block 220 contacts the bar stock and bends it. At the same time, the inner wall of the punch 230 and the outer wall of the first positioning frame 120 of the lower die 100 are fitted and misaligned, forming a shearing fit similar to scissors to ensure a smooth cut and ensure the length of the cut bar stock.
[0029] Two mounting brackets 240 are spaced apart at the bottom of the upper mold 200, while the first pressing block 210 is located between the two mounting brackets 240.
[0030] The second pressure block 220 is hinged to the bottom of the upper mold 200, and the second pressure block 220 and the guide part 121 on the two positioning frames have overlapping tracks in the vertical direction to form a sliding fit. That is, after the second pressure block 220 abuts against the guide part 121, the second pressure block 220 will rotate as it continues to move down, thereby achieving the bending of both ends of the bar.
[0031] Specifically, the bottom of the two mounting brackets 240 is provided with mounting holes arranged in the front-back direction, and the top of the two second pressure blocks 220 is provided with rotating shafts 221 corresponding to the mounting holes. The second pressure blocks 220 are hinged to the mounting brackets 240 through the rotating shafts 221, so that the second pressure blocks 220 can swing inward around the axis in the front-back direction like a pendulum.
[0032] Furthermore, in order to control the elastic ejector 140 in a coordinated manner, a downwardly extending abutment slope 251 is provided at the bottom of the mold base 250. The slope of the abutment slope 251 matches the driving slope 141a on the slide block 141 of the lower mold 100. When the mold base 250 moves downward with the upper mold 200, the abutment slope 251 and the driving slope 141a can squeeze the slide block 141 to move backward, thereby driving the ejector rod 142 to move backward, realizing its switching from the ejection position to the avoidance position.
[0033] Working principle and operation process description: In a single stamping cycle, the actions of this compound die unfold strictly according to a timing sequence: Feeding and positioning: In the initial state, the upper mold 200 is at its highest point. The bar stock is passed through the feeding hole 151 of the placement frame 150 and pushed inward. The bar stock passes through the supporting top surface 122 of the first positioning frame 120 and the top surface of the first core 110 in sequence until the front end of the bar stock abuts against the abutting and limiting surface 131 of the second positioning frame 130. At this time, the bar stock positioning is completed. Cutting and Avoidance Stage: The upper die 200 of the punch press moves downward. Since the height of the punch 230 is the lowest, the punch 230 contacts the bar first and cooperates with the first positioning frame 120 to cut the bar outside the fixed length range instantly. Almost at the same time, the abutting inclined surface 251 at the bottom of the die base 250 touches the driving inclined surface 141a of the slide block 141 of the lower die 100. As the upper die 200 continues to press down, due to the wedge-shaped effect of the inclined surface, the abutting inclined surface 251 forcibly pushes the slide block 141 backward (compressing the second spring 143), so that the slide block 141 and the ejector rod 142 move from the "ejection position" to the "avoidance position", completely giving way to the forming area of the first core 110. Main bending stage: After the bar is cut off, the upper die 200 continues to descend. The first suspended pressure block 210 first presses down on the middle section of the cut bar, pressing it tightly on the top surface of the first core 110. At this time, the middle section is formed. As the upper die 200 descends further, the first pressure block 210 stops descending because it is pressed against the first core 110. The first spring 211 at its top begins to compress and store force, while the second pressure block 220 on the upper die 200 continues to descend. Side bending stage (hinged forming): The upper mold 200 drives the two second pressure blocks 220 to continue to descend. The bottom edge of the second pressure block 220 begins to touch and slide down along the guide slope (guide part 121) on the two positioning frames. Since the guide slope is contracted and inclined towards the first core 110, the sliding fit forces the two suspended second pressure blocks 220 to rotate inward (towards the first core 110) around the top pivot 221. The inner side of the second pressure block 220 bends the two ends of the bar material that are suspended inward, so that they fit tightly against the two sides of the first core 110. Full mold closing: At this point, the bottom dead center of the stamping is reached. The bottom surface of the first pressure block 210, the top surface and two sides of the first core 110, and the inner sides of the two inwardly rotated second pressure blocks 220 together form a closed inverted triangular cavity. The cut bar is perfectly extruded into an inverted triangular bent bar in the cavity. Mold opening and automatic demolding: The upper die 200 driven by the punch press rises back. As the second pressure block 220 moves upward and disengages from the guide slope, it loses its lateral pressure. The first pressure block 210 releases its clamping force on the bar as the upper die 200 rises. At this time, the formed inverted triangular bent bar is usually stuck on the first core 110 due to the deformation clamping force. When the upper die 200 continues to rise, the abutting slope 251 at the bottom of the die base 250 moves upward and disengages from the driving slope 141a of the slide block 141. The slide block 141 of the lower die 100 instantly loses its rearward constraint. Under the strong rebound force of the second spring 143, the slide block 141 carries the ejector rod 142 and thrusts forward violently (reset to the ejection position). The front end of the ejector rod 142 directly hits the rear side of the formed bent bar, peeling the bent bar off the first core 110 and ejecting it. Thus, a fully automatic cutting, bending forming and automatic demolding process is completed.
[0034] In this embodiment, a forming composite mold for bending a rod is disclosed, including a lower mold 100 and an upper mold 200. The lower mold 100 is provided with a first core 110, two positioning frames with guide portions 121 respectively disposed on both sides thereon, and an elastic ejector 140. The upper mold 200 is provided with a first pressing block 210 elastically connected, two second pressing blocks 220 respectively disposed on both sides and hinged to the bottom of the upper mold 200, and a punch 230 corresponding to one of the positioning frames. In the vertical direction, the bottom height of the punch 230 is lower than that of the second pressing blocks 210. When the mold is closed, the punch 230 first cuts the bar material on the bottom surface of the block 220. Then, the second pressure block 220 slides and rotates inward with the guide part 121 to achieve lateral bending of the bar material. At the same time, the upper mold 200 abuts against the driving surface of the elastic ejector 140 to make it retreat to the avoidance position. When the mold is opened, the elastic ejector 140 loses the abutment force and automatically pops out to the ejection position to push down the formed bent bar. The cutting, bending and forming and automatic demolding processes are integrated into one stamping stroke, which significantly improves production efficiency and forming accuracy.
[0035] The technical solution of the present invention has been described in detail above with reference to the accompanying drawings. The described embodiments are used to help understand the concept of the present invention. The specific embodiments described herein are merely illustrative examples of the spirit of the present invention. Those skilled in the art to which this invention pertains can make various modifications or additions to the described specific embodiments or use similar methods to replace them, but without departing from the spirit of the present invention or exceeding the scope defined by the appended claims.
[0036] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.
[0037] Furthermore, in this invention, descriptions involving terms such as "first," "second," and "a" are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.
[0038] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.
[0039] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are feasible for those skilled in the art. If the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.
Claims
1. A composite mold for forming a bent rod, characterized in that, Including the lower mold and the upper mold; The lower mold is provided with a first core, two positioning frames with guide portions located on both sides of it, and an elastic ejector. The upper die is provided with a first pressure block that is elastically connected, two second pressure blocks disposed on both sides thereon, and a punch corresponding to one of the positioning frames. Both second pressure blocks are hinged to the bottom of the upper die. The first pressing block and the first core are positioned directly opposite each other in the vertical direction; The second pressure block and the guide part have overlapping trajectories in the vertical direction to form a sliding fit; In the vertical direction, the bottom height of the punch is lower than the bottom height of the second pressure block; The elastic ejector has a clearance position and an ejection position, and the elastic ejector is configured to have a driving surface that abuts against the bottom of the upper mold to achieve switching from the ejection position to the clearance position.
2. The forming composite mold for bending a rod according to claim 1, characterized in that, One of the positioning frames is a first positioning frame with a supporting top surface, and the other positioning frame is a second positioning frame with an abutting limiting surface; the punch is offset from the inner wall surface of the first positioning frame.
3. The forming composite mold for bending a rod according to claim 2, characterized in that, The lower mold is also provided with a placement frame, which is located outside the first positioning frame and has a feeding through hole. The height of the bottom of the feeding through hole is the same as the height of the support top surface.
4. The forming composite mold for bending a rod according to claim 1, characterized in that, The upper mold has two spaced mounting brackets at its bottom, and the bottom of each mounting bracket has mounting holes arranged in the front-to-back direction. The second pressure block has a rotating shaft arranged in the front-to-back direction, and the rotating shaft is rotatably arranged in the mounting holes.
5. The forming composite mold for bending a rod according to claim 4, characterized in that, The top of the first pressure block is provided with a first spring, and it is suspended from the bottom of the upper mold by the first spring; The first pressure block is located between the two mounting brackets.
6. The forming composite mold for bending a rod according to claim 1, characterized in that, The bottom of the upper mold is also provided with a mold base, the first pressure block, the second pressure block and the punch are all located in the mold base, and the bottom of the mold base is provided with an abutting slope corresponding to the driving surface.
7. The forming composite mold for bending a rod according to claim 6, characterized in that, The elastic ejector includes a slide block, an ejector rod, and a second spring. One end of the second spring is connected to the rear side of the slide block, and the other end of the second spring is connected to the lower mold along the front-rear direction. One end of the ejector rod is connected to the front side of the slide block, and the other end of the ejector rod can extend into one side of the first core to eject the formed bent rod.
8. The forming composite mold for bending a rod according to claim 7, characterized in that, The driving surface is configured as a driving ramp, which is arranged at an angle on the top of the slide.
9. The forming composite mold for bending a rod according to claim 1, characterized in that, The guide section is a guide slope that is inclined from top to bottom toward the first core.
10. A forming composite mold for bending rods according to claim 1, characterized in that, In the fully closed mold state, the bottom surface of the first pressure block, the top surface and two sides of the first core, and the inner sides of the two rotated second pressure blocks together form an inverted triangular cavity.