Chain wheel fine blanking die

Abstract

The chain wheel fine blanking die comprises an upper die body and a lower die body, the upper die body comprises an upper die base, an upper base plate, a middle plate, a punch-die and a gear ring plate which are sequentially arranged from top to bottom, the lower die body comprises a lower die plate and a lower die base which are sequentially arranged from top to bottom, and the gear ring plate is arranged in a sliding mode relative to the lower die plate; the gear ring plate comprises a first oil groove, a forming hole and a second oil groove which are sequentially formed in the plate conveying direction, the punch-die is arranged on the forming hole in a penetrating mode, the shape of the punch-die is matched with that of a chain wheel, the gear ring plate is provided with a V-shaped material blocking rib on the outer side of the edge of the forming hole, and the first oil groove corresponds to the peripheral shape of the chain wheel. The second oil groove corresponds to the peripheral shape of the chain wheel and the edge of a through hole in the chain wheel, and lubricating oil is arranged in the first oil groove and the second oil groove. The chain tooth forming device has the advantages that lubrication can be provided for the chain tooth forming position before stamping, the friction force of a punch-die to a plate during stamping is reduced, the width edge of the plate can be reduced, and waste is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of chain wheel fine blanking die, in particular to a chain wheel fine blanking die. BACKGROUND

[0002] Chain wheel is a kind of wheel with embedded tooth type chain tooth, which is used to mesh with block with accurate pitch on chain ring or cable. Chain wheel is widely used in mechanical transmission of chemical industry, textile machinery, food processing, instruments and meters, petroleum industry and other industries. The existing chain wheel is usually formed by fine blanking die.

[0003] Chinese patent application authorization announcement No. CN209206235 U, on August 6, 2019, the "mold for producing high precision stamping chain wheel", the application discloses a mold for producing high precision stamping chain wheel, including upper die plate, lower die plate, limit block, upper die plate lower surface is provided with upper punch, one side of upper punch is provided with guide column, upper punch upper surface is provided with support plate, lower surface of support plate is provided with limit block, inner hole of upper punch is provided with middle hole punch rod, one side of middle hole punch rod is provided with weight reduction hole punch rod, one side of weight reduction hole punch rod is provided with upper push rod, upper surface of upper push rod is provided with upper push spring, lower surface of upper punch is provided with raw material plate, lower surface of raw material plate is provided with lower concave die. The chain wheel fine blanking is completed by the cooperation of upper punch and lower concave die.

[0004] In order to ensure the fine blanking precision of chain wheel, the tooth ring plate needs to be set to press the chain wheel to provide edge pressure, so as to avoid the edge cracking of raw material plate at fine blanking position. The existing technology has the following disadvantages: when fine blanking, the upper punch needs to pass through the raw material plate, and the edge side of the upper punch will generate a large friction force on the raw material plate during stamping. In order to reduce the influence of this friction force, enough thickness needs to be reserved at the edge of the raw material plate at the fine blanking position, so as to avoid the tearing of the edge of the raw material plate by the friction force, especially the edge in the width direction of the raw material plate, which increases the waste of fine blanking of the raw material plate, greatly increasing the cost of fine blanking forming. SUMMARY

[0005] In order to overcome the above-mentioned deficiencies in the prior art, the present application provides a chain wheel fine blanking die, which can provide lubrication to the chain tooth forming position before stamping, reduce the friction force of the punch and die on the plate during stamping, so that the width edge of the plate can be reduced, the generation of waste can be reduced, and the friction force between the chain wheel and the plate during blanking can be reduced, avoiding the scratch generated by dry friction between the edge of the chain wheel after fine blanking and the plate during blanking.

[0006] In order to achieve the above-mentioned purpose, the present application adopts the following technical scheme: The chain wheel fine blanking die comprises an upper die and a lower die, the upper die comprises, from top to bottom, an upper die seat, an upper cushion plate, an intermediate plate, a convex-concave die and a gear ring plate, the lower die comprises, from top to bottom, a lower die plate and a lower die seat, the gear ring plate is slidably arranged relative to the lower die plate, the gear ring plate comprises, from top to bottom along the plate conveying direction, a first oil groove, a forming hole and a second oil groove, the convex-concave die is arranged through the forming hole, the outer shape of the convex-concave die is matched with the outer shape of the chain wheel, a V-shaped material blocking rib is arranged outside the forming hole edge of the gear ring plate, the first oil groove is arranged corresponding to the outer peripheral shape of the chain wheel, and the second oil groove is arranged corresponding to the outer peripheral shape of the chain wheel and the inner hole edge of the chain wheel, and lubricating oil is arranged in the first oil groove and the second oil groove.

[0007] When the gear ring plate slides relative to the plate to complete fine blanking, the V-shaped material blocking rib is embedded into the plate to form a wrapping limit, the lower side of the gear ring plate is attached to the upper side of the plate to provide pressure, the first oil groove and the second oil groove provide lubricating oil for the plate when the gear ring plate is attached to the plate, the first oil groove lubricates the outer peripheral edge position of the chain wheel fine blanking, reduces the friction of the convex-concave die on the plate, and further maintains the fine blanking precision under the condition that the width dimension of the plate is reduced, reduces the generation of waste materials, and the second oil groove lubricates the outer peripheral edge position and the inner hole edge position of the chain wheel separated from the plate after fine blanking, the fine-blanked plate needs to continue to move linearly, and the waste material of the chain wheel and the inner hole formed by the chain wheel needs to be cut off, the second oil groove is arranged to lubricate the waste material of the chain wheel relative to the plate and the inner hole position, reduce the friction, avoid the generation of chain wheel edge scratches, and improve the surface performance of the chain wheel.

[0008] Preferably, the lower die plate is provided with a blanking insert hole corresponding to the forming hole, and the blanking insert hole is provided with a matching oil groove corresponding to the first oil groove and the second oil groove on both sides. The matching oil groove can supply oil to the lower side of the plate, further reduce the frictional stress of the plate before and after the chain wheel fine blanking, and improve the lubrication effect of the chain wheel edge.

[0009] Preferably, the cross-sectional shape of the first oil groove is circular arc type, the radius range of the first oil groove is between 0.8 to 1.5 mm, and the groove depth of the first oil groove is smaller than the radius. The control of the radius range of the first oil groove realizes the control of the amount of lubricating oil, and the groove depth of the first oil groove is smaller than the radius, so that the cross-sectional circular arc central angle of the first oil groove is smaller than 180, the first oil groove is an open structure, and is not easy to be crushed and deformed during the pressing process of the gear ring plate, and the outflow of the lubricating oil in the first oil groove is facilitated.

[0010] As preferred, the cross-sectional shape of the second oil groove is circular arc type, the radius of the second oil groove ranges between 0.8 and 1.5 mm, and the groove depth of the second oil groove is less than the radius. The control of the amount of lubricating oil is realized by the control of the radius range of the second oil groove, and the groove depth of the second oil groove is less than the radius, so that the cross-sectional circular arc center angle of the second oil groove is less than 180, the second oil groove is open structure, and is not easy to be crushed and deformed during the pressing of the gear ring plate, and the outflow of the lubricating oil in the second oil groove is facilitated.

[0011] According to the chain wheel fine blanking die of claim 1, the outer periphery of the first oil groove and the second oil groove is in the same direction as the hole wall edge of the forming hole, so that the lubricating position is matched with the chain wheel position generated by fine blanking, especially the chain tooth position.

[0012] As preferred, the interval between the V-shaped material blocking rib and the corresponding forming hole edge is 2.7 mm, which has reliable material blocking effect.

[0013] As preferred, the first oil groove is provided with an elastic oil bag which is pressed to extrude lubricating oil, the gear ring plate is moved downward during fine blanking, the lower die plate and the gear ring plate are respectively attached to and pressed against the plate, the elastic oil bag is pressed to extrude lubricating oil and diffuse along the first oil groove. During the pressing of the gear ring plate, the elastic oil bag can extrude lubricating oil, and since the gear ring plate and the plate are attached at this time, the extruded lubricating oil can only diffuse along the first oil groove on the surface of the plate, so that the continuous supplement of the lubricating oil in the first oil groove is realized during fine blanking, and the reliable lubricating effect of the first oil groove is ensured.

[0014] As preferred, the elastic oil bag comprises a collapsible bag body and an elastic reset mechanism arranged in the bag body, and / or the elastic oil bag is made of elastic material. The elastic structure of the elastic oil bag enables it to be automatically reset to the expanded state, so that it can supply oil to the first oil groove under pressure during the next fine blanking.

[0015] As preferred, the elastic oil bag comprises a bag body and an oil passing nozzle, the bag body is filled with lubricating oil, the oil passing nozzle is directed to and communicates with the first oil groove, an elastic diaphragm is arranged in the oil passing nozzle, an oil passing opening in the closed state is arranged on the elastic diaphragm to prevent the lubricating oil from flowing out, and the lubricating oil in the bag body is extruded to flow out when the bag body is extruded. The arrangement of the elastic diaphragm avoids the leakage of the elastic oil bag, ensures the reliability of the lubricating oil addition, and avoids waste.

[0016] The present application has the advantages that the chain tooth forming position can be lubricated before stamping, the friction between the convex and concave dies and the plate during stamping is reduced, the width edge of the plate can be reduced, the generation of waste material is reduced, the friction between the chain wheel and the plate during blanking is reduced, and scratches caused by dry friction between the edge of the fine-blanked chain wheel and the plate during blanking are avoided. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1is a structural schematic view of a chain wheel fine blanking die disclosed in one of the embodiments of the present application.

[0018] Figure 2 is a top view schematic view of the chain wheel fine blanking die disclosed in one of the embodiments of the present application when the function surfaces of the components are integrated together.

[0019] Figure 3 is a structural schematic view of a gear ring plate in the chain wheel fine blanking die disclosed in one of the embodiments of the present application.

[0020] Figure 4 is a structural schematic view of an upper die holder in the chain wheel fine blanking die disclosed in one of the embodiments of the present application.

[0021] Figure 5 is a structural schematic view of a lower die holder in the chain wheel fine blanking die disclosed in one of the embodiments of the present application.

[0022] Figure 6 is a structural schematic view of a lower die plate in the chain wheel fine blanking die disclosed in one of the embodiments of the present application.

[0023] Figure 7 is a relative position schematic view of the gear ring plate and the first oil groove corresponding to the oil injection nozzle in the chain wheel fine blanking die disclosed in one of the embodiments of the present application.

[0024] Figure 8 is a structural schematic view of the V-shaped material blocking rib provided on the gear ring plate in the chain wheel fine blanking die disclosed in one of the embodiments of the present application.

[0025] Figure 9 is a structural schematic view of the first oil groove provided on the gear ring plate in the chain wheel fine blanking die disclosed in one of the embodiments of the present application.

[0026] Figure 10 is a structural schematic view of the internal structure of the elastic oil bag assembled and arranged with the gear ring plate in the chain wheel fine blanking die disclosed in one of the embodiments of the present application.

[0027] Figure 11 is a structural schematic view of the internal structure of the elastic oil bag assembled and arranged with the gear ring plate in the chain wheel fine blanking die disclosed in one of the embodiments of the present application.

[0028] Figure 12 is a structural schematic view of the internal structure of the elastic oil bag assembled and arranged with the gear ring plate in the chain wheel fine blanking die disclosed in one of the embodiments of the present application.

[0029] In the diagram: 1. Upper mold base; 2. Upper backing plate; 3. Middle plate; 4. Punch and die; 5. Gear ring plate; 6. Lower mold plate; 7. Gas spring; 8. Lower mold base; 9. Guide post; 10. Guide sleeve; 11. First oil groove; 12. Forming hole; 13. Second oil groove; 14. V-shaped material blocking rib; 15. Blanking insert hole; 16. Matching oil groove; 17. Lower die; 18. Elastic oil bladder; 19. Oil injection nozzle; 20. Fixed bracket; 21. Bladder body; 22. Elastic reset mechanism; 23. Elastic membrane; 24. First oil cavity; 25. Second oil cavity; 26. Partition plate; 27. Oil level detector; 28. Control valve; 29. ​​Plate; 30. Oil inlet. Detailed Implementation

[0030] The present invention will now be further described with reference to the accompanying drawings and specific embodiments.

[0031] like Figures 1 to 6 As shown, a sprocket fine blanking die disclosed in one embodiment of the present invention includes an upper die and a lower die. The upper die includes an upper die base 1, an upper pad plate 2, an intermediate plate 3, a punch and die 4, and a gear ring plate 5 arranged sequentially from top to bottom. The lower die includes a lower die plate 6 and a lower die base 8 arranged sequentially from top to bottom. A guide post 9 is provided on the lower die base 8. The gear ring plate 5 is slidably arranged relative to the lower die plate 6. The gear ring plate 5 includes a first oil groove 11, a forming hole 12, and a second oil groove 13 arranged sequentially along the conveying direction of the sheet 29. The punch and die 4 are inserted into the forming hole 12. The shape of the punch and die 4 is adapted to the shape of the sprocket. The gear ring plate 5 is provided with a V-shaped material blocking rib 14 on the outer side of the edge of the forming hole 12. The first oil groove 11 is arranged corresponding to the outer circumferential shape of the sprocket. The second oil groove 13 is arranged corresponding to the outer circumferential shape of the sprocket and the edge of the through hole inside the sprocket. Lubricating oil is provided in both the first oil groove 11 and the second oil groove 13.

[0032] In the above embodiments, with Figure 2 For example, the plate 29 is conveyed from right to left. The plate 29 first passes through the first oil groove 11, then through the forming hole 12, and finally through the second oil groove 13. When the plate 29 passes through the first oil groove 11, the lubricating oil inside the first oil groove 11 flows to the plate 29 to form a lubricating layer corresponding to the position of the forming hole 12 when the gear ring plate 5 is pressed down. When the plate 29 continues to move through the forming hole 12, the forming position of the outer edge of the punch and die 4 on the workpiece corresponds to the lubricating layer formed by the forming hole 12, that is, the first oil groove 11 on the plate 29. When the punch and die 4 is pressed down, the lubricating layer achieves lubrication between the punch and die 4 and the plate 29, reducing the force on the edge of the plate 29. With the help of the V-shaped material blocking rib 14, the forming quality can be guaranteed, and the width dimension of the plate 29 in the vertical conveying direction can be smaller, reducing the generation of waste. After the formed sheet metal 29 passes through the second oil groove 13, the lubricating oil inside the second oil groove 13 flows to the edge of the stamped sprocket when the gear ring plate 5 is pressed down, which facilitates the unloading of the sprocket and the waste material corresponding to the internal through hole. The tooth ring plate 5 disclosed in the above embodiment is fixedly connected to the lower side of the middle plate 3, the middle plate 3 is in sliding fit with the guide sleeve 10 and the guide column 9, the male and female die 4 is fixed to the upper pad plate 2, the male and female die 4 passes through the tooth ring plate 5, when the upper die seat 1 and the upper pad plate 2 are pressed downward along the guide column 9, the male and female die 4 is pressed downward together, the upper die seat 1 is connected with the middle plate 3 through the gas spring 7, the middle plate 3 and the tooth ring plate 5 are also pressed downward together, when the tooth ring plate 5 is in close contact with the plate 29, the gas spring 7 is compressed, the male and female die 4 continues to be pressed downward, and the fine punching of the plate 29 is completed, the tooth ring plate 5 is in close contact with the upper surface of the plate 29, the V-shaped material blocking rib 14 is used to realize the pressing and blocking of the material, and the first oil groove 11 and the second oil groove 13 are used to provide lubricating oil to the upper surface of the plate 29.

[0033] In the embodiment, the outer periphery of the first oil groove 11 and the second oil groove 13 is in the same direction as the hole wall edge of the forming hole 12. The lower die plate 6 is provided with a blanking insert hole 15 corresponding to the forming hole 12, and the blanking insert hole 15 is provided with a matching oil groove 16 corresponding to the first oil groove 11 and the second oil groove 13 on both sides. The blanking insert hole 15 is embedded with a blanking insert. The blanking insert is provided with a lower die 17 and a plurality of ejector pins, and the lower die 17 is matched with the male and female die 4. How the upper die and the lower die move relative to each other to realize fine punching and blanking of waste materials and products is mature prior art in the field, such as the patent CN 209206235 U granted on August 6, 2019, “A mold for producing high-precision stamping chain wheels”, because how the upper die and the lower die fine punch and blank the waste materials and products do not involve the improvement of the present application, and therefore will not be expanded.

[0034] As one of the embodiments of the present application, the first oil groove 11 has a circular arc cross-sectional shape, the radius of the first oil groove 11 is 1 mm, and the groove depth of the first oil groove 11 is 0.8 mm. The second oil groove 13 has a circular arc cross-sectional shape, the radius of the second oil groove 13 is 1 mm, and the groove depth of the second oil groove 13 is 0.8 mm. The interval between the V-shaped material blocking rib 14 and the corresponding forming hole 12 edge is 2.7 mm. The shapes of the first oil groove 11, the second oil groove 13 and the V-shaped material blocking rib 14 can be referred to as shown in Figure 8 and Figure 9 .

[0035] The first oil groove 11 has a cross-section arc center angle less than 180 degrees, and the first oil groove 11 is an open structure, which is not easy to be crushed and deformed during the pressing of the gear ring plate 5, and facilitates the outflow of the lubricating oil in the first oil groove 11. The second oil groove 13 has a cross-section arc center angle less than 180 degrees, and the second oil groove 13 is an open structure, which is not easy to be crushed and deformed during the pressing of the gear ring plate 5, and facilitates the outflow of the lubricating oil in the second oil groove 13. Since the groove depth of the first oil groove 11 is less than the radius of the first oil groove 11, after the first oil groove 11 is filled with oil, the lubricating oil can flow out from the first oil groove 11 to the plate material 29, ensuring the amount of lubricating oil. The second oil groove 13 can also flow out to the edge of the sprocket.

[0036] As one of the embodiments of the present application, a sprocket fine punching die is provided with an elastic oil bag 18 for extruding lubricating oil under pressure. When the fine punching die is fine punched, the gear ring plate 5 moves downward, the lower die plate 6 and the gear ring plate 5 are respectively attached to and pressed against the plate material 29, the elastic oil bag 18 is extruded to spread along the first oil groove 11. The gear ring plate 5 is pressed and the oil bag is extruded to supply oil to the first oil groove 11.

[0037] In this embodiment, one side of the elastic oil bag 18 is fixed on the circumferential side of the gear ring plate 5, and the lower end of the elastic oil bag 18 protrudes to the outside of the gear ring plate 5, so that when the gear ring plate 5 is pressed against the plate material 29, the elastic oil bag 18 is also extruded. The elastic oil bag 18 includes an oil injection nozzle 19 connected to the first oil groove 11, as shown in Figure 3 and Figure 7 As shown in Figure 7 , the first oil groove 11 and the second oil groove 13 correspond to the straight lines on the edge of the gear ring plate 5, so that the first oil groove 11 and the second oil groove 13 are discontinuous channels, not closed annular channels, which facilitates the oil injection nozzle 19 to supply oil to the first oil groove 11 or the second oil groove 13. As shown in

[0038] As a simple alternative to the above scheme, an oil cavity is provided in the gear ring plate 5, and the oil cavity is controlled by a valve to supply lubricating oil to the first oil groove 11 and the second oil groove 13 through a hole in the gear ring plate 5.

[0039] Further, as shown in Figure 10 , the side of the elastic oil bag 18 is provided with a fixed bracket 20, the fixed bracket 20 is screwed to the gear ring plate 5, and the fixed bracket 20 is provided with a waist-shaped hole matched with the screw, so that the height of the fixed bracket 20 has a certain adjustment ability. As shown in Figure 10As shown, the elastic oil bag 18 comprises a collapsible bag body 21 and an elastic reset mechanism 22 arranged in the bag body 21. For example, in order to ensure the bag body 21 to stretch and contract in the lifting direction of the ring plate 5, a folded tube-shaped part is arranged in the middle of the bag body 21, and when the lower end of the bag body 21 is pressed upward, the bag body 21 contracts along the folded tube part, and the elastic reset mechanism 22 is a spring arranged along the longitudinal axis of the bag body 21, which provides the reset force for the lower end of the bag body 21.

[0040] In the embodiment, in order to reduce the leakage of lubricating oil, further, the elastic oil bag 18 further comprises an oil passing nozzle, the bag body 21 is filled with lubricating oil, and the wall surface or the upper end surface of the bag body 21 is provided with an oil inlet 30 which is controlled to open and close by a cover or a valve. When the bag body 21 is filled with oil, the oil inlet 30 is opened. When the bag body 21 is pressed to supply oil outwardly, the oil inlet 30 is closed. The oil passing nozzle is connected to the first oil groove 11, and an elastic diaphragm 23 is arranged in the oil passing nozzle, and the elastic diaphragm 23 is provided with an oil passing opening which is normally closed to prevent the lubricating oil from flowing out. The oil passing opening of the bag body 21 is located at the lower end of the side surface of the bag body 21, which ensures the full use of the lubricating oil. When the lower end of the bag body 21 is pressed by the plate material 29, the bag body 21 is longitudinally folded and contracted, at this time, the oil inlet 30 is closed, the internal pressure of the bag body 21 increases, the oil passing opening of the elastic diaphragm 23 is pushed open, and the lubricating oil in the bag body 21 flows outwardly from the oil passing opening to the oil filling nozzle 19 through the pipeline, and the oil filling of the first oil groove 11 is completed.

[0041] As a simple replacement of the above scheme, as shown in FIG. 4, Figure 11 As shown, the elastic oil bag 18 is a single bag body 21, and the elastic reset mechanism 22 is not arranged in the bag body 21, and the elastic oil bag 18 is made of elastic material, and the elastic reset of the elastic oil bag 18 is realized by the elasticity of the elastic oil bag 18.

[0042] As one of the embodiments of the present application, a chain wheel fine blanking die is provided, as shown in FIG. 5, Figure 12As shown, the capsule 21 is provided with the first oil cavity 24 and the second oil cavity 25 arranged in upper and lower intervals, the first oil cavity 24 and the second oil cavity 25 are provided with the partition plate 26, the upper surface of the partition plate 26 is provided with the oil amount detection meter 27 located in the first oil cavity 24, the partition plate 26 is provided with the control valve 28, the control valve 28 is opened to communicate the first oil cavity 24 and the second oil cavity 25. The lower end side wall of the second oil cavity 25 is provided with the folded pipe section made of elastic material, the upper end side wall of the second oil cavity 25 is the circular ring pipe wall made of rigid material, the oil passing port is located at the uppermost end of the circular ring pipe wall, and the two ends of the spring are respectively abutted against the partition plate 26 and the bottom wall of the second oil cavity 25. The second oil cavity 25 keeps the state of full of lubricating oil, when the lower end of the capsule 21 is subjected to pressure, the lubricating oil pushes away the oil passing port of the elastic diaphragm 23 and flows outwards, when the ring gear plate 5 is separated from the plate material 29 upwards, the lower end of the capsule 21 is reset under the action of the spring, at this time, the control valve 28 is opened, the lubricating oil in the second oil cavity 25 is replenished, the position of the oil passing port is kept constant, the position will not change due to the contraction of the capsule 21, the oil amount led out by the contraction of the capsule 21 can be kept unchanged, so as to ensure that the lubricating oil amounts obtained by each sprocket in the first oil groove 11 are close, and the influence of the lubricating oil amounts in the first oil groove 11 on the fine punching quality due to the different positions is excluded.

Claims

1. A sprocket fine blanking die, comprising an upper die and a lower die, the upper die comprising an upper die base, an upper backing plate, an intermediate plate, a punch and die, and a gear ring plate arranged sequentially from top to bottom, the lower die comprising a lower die plate and a lower die base arranged sequentially from top to bottom, the gear ring plate being slidably disposed relative to the lower die plate, characterized in that... The gear ring plate includes a first oil groove, a forming hole, and a second oil groove arranged sequentially along the conveying direction of the plate. The punch and die are inserted into the forming hole, and the shape of the punch and die is adapted to the shape of the sprocket. The gear ring plate is provided with a V-shaped material blocking rib on the outer side of the forming hole. The first oil groove is set according to the outer circumferential shape of the sprocket, and the second oil groove is set according to the outer circumferential shape of the sprocket and the edge of the through hole inside the sprocket. Lubricating oil is provided in both the first oil groove and the second oil groove.

2. The sprocket fine stamping die according to claim 1, characterized in that, The lower template is provided with blanking insert holes corresponding to the forming holes, and the blanking insert holes are provided with matching oil grooves on both sides corresponding to the first oil groove and the second oil groove.

3. The sprocket fine stamping die according to claim 1, characterized in that, The first oil tank has a circular arc cross-section, and its radius ranges from 0.8 to 1.5 mm. The depth of the first oil tank is less than its radius.

4. A sprocket fine stamping die according to claim 3, characterized in that, The second oil tank has a circular arc cross-section, and its radius ranges from 0.8 to 1.5 mm. The depth of the second oil tank is less than its radius.

5. A sprocket fine stamping die according to claim 1, characterized in that, The outer periphery of the first oil groove and the second oil groove are in the same orientation as the edge of the hole wall of the forming hole.

6. A sprocket fine stamping die according to claim 1, characterized in that, The distance between the V-shaped material-blocking rib and the edge of the corresponding forming hole is 2.7 mm.

7. A sprocket fine stamping die according to any one of claims 1 to 6, characterized in that, The first oil groove and the second oil groove are respectively equipped with elastic oil bladders that are pressurized and extruded with lubricating oil. When the fine blanking die is being finely blanked, the gear ring plate moves downward, the lower template and the gear ring plate are respectively attached to and pressed against the plate, and the elastic oil bladder is pressurized and extrudes the lubricating oil, which then diffuses along the first oil groove or the second oil groove.

8. A sprocket fine stamping die according to claim 7, characterized in that, The elastic oil bladder includes a contractile bladder body and an elastic reset mechanism disposed within the bladder body; and / or, the elastic oil bladder is made of an elastic material.

9. A sprocket fine stamping die according to claim 7, characterized in that, The elastic oil bladder includes a bladder body and an oil outlet. The bladder body is filled with lubricating oil, and the oil outlet faces and is connected to the first oil groove or the second oil groove. An elastic membrane is provided inside the oil outlet, and the elastic membrane has an oil outlet that is normally closed to prevent the lubricating oil from flowing out. When the bladder body is squeezed, the lubricating oil inside the bladder body opens the oil outlet and flows outward.

Images