A composite forging process and die for an integral 90-degree fitting

Abstract

The application introduces a composite forging forming process and die of an integrated 90-degree joint; the one-time cold forging die and the secondary cold forging die are adopted, the workpiece is punched and extruded in combination through the composite forging forming process, only the inner hole groove part of the plug-in end needs to be supplemented by machining, the rest is all forged and formed, the overall machining precision is high, the machining steps are reduced, the production efficiency is improved, and the material waste is greatly reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of metal cold forging forming die and process, in particular to a composite forging forming process and die of an integrated 90-degree joint. BACKGROUND

[0002] The integrated 90-degree joint of the high-load large-current new energy storage connector is a copper piece, and its structure is shown in Figure 11 The joint mainly comprises a plug-in end, a connecting bridge and a wire harness end, the plug-in end and the wire harness end are provided with inner holes, the length of the wire harness end is longer than that of the plug-in end, the wire harness end is connected with a conductive copper wire, and the conductive copper wire is connected after being pressed into the inner hole of the wire harness end; the inner hole of the plug-in end is connected with the joint at the other end, and since the plug-in end needs to be disassembled, an annular spring buckle is placed in the inner hole groove for fixation.

[0003] The existing processing of the integrated 90-degree joint mainly adopts two schemes:

[0004] Scheme one: after a rectangular cuboid forging piece is simply forged, the whole surface is milled to form, and then the inner holes at two ends are machined, but since the 90-degree joint is made of pure copper, the material volume required for the whole milling is large, the material required for a single piece is much, copper is a precious metal, the material waste is large, the milling needs a long time, and the processing efficiency is not high, and the production efficiency of this method cannot meet the demand of the market for the quantity of the part;

[0005] Scheme two: after one end of a pipe is flattened, the connecting bridge part is formed first, the large hole of the connecting bridge is machined, the plug-in end part of the rod is machined, the plug-in end part of the rod is pressed into the inner hole of the connecting bridge, and then the two parts are welded to form, and then the inner holes at two ends are machined, mainly to ensure that the perpendicularity of the two holes is within 0.05mm and the height difference error of the end face of the plug-in end to the hole axis of the wire harness end needs to be controlled within ±0.1mm; since the workpiece needs to be electroplated after milling, acid is easy to enter the gap during the acid washing process of electroplating, and after water washing, acid still remains in the gap, there is a risk of acid spitting after electroplating, and there is a risk of welding separation in the process of pressing and welding, and in the case of large current, the pressing joint part will be seriously heated. SUMMARY

[0006] The purpose of the present application is to overcome the shortcomings of the prior art, provide a composite forging forming process and die of an integrated 90-degree joint, which can achieve near net forming, high machining precision and improved production efficiency.

[0007] The technical scheme adopted by the present application is:

[0008] A composite forging forming process of an integrated 90-degree joint, the specific steps are:

[0009] S1: shearing blanking: according to the drawing requirements, round bar blanking is adopted, the outer circle of the round bar is free of cracks and slag, and the roughness is within Ra1.6;

[0010] S2: primary cold forging: the wire harness end inner hole and outer circle and the plug-in end outer circle of the blank workpiece are processed by using a press and a primary cold forging die;

[0011] S3: secondary cold forging: the blank workpiece after the primary cold forging is placed into a secondary cold forging die, and the connecting bridge part between the wire harness end and the plug-in end is formed by using a press;

[0012] S4: edge cutting: the excess flash of the connecting bridge part is cut off by using an edge cutting die;

[0013] S5: supplementary machining: the inner hole groove of the plug-in end is machined.

[0014] A composite forging forming primary cold forging die for an integrated 90-degree joint, comprising a die upper die assembly and a die lower die assembly;

[0015] The die upper die assembly comprises a die upper die plate, an inverted pyramid pad, an upper die fixed plate, a male die elastic sleeve, a male die clamping sleeve, a male die, an elastic upper die sleeve, a male die guide sleeve and a die closing plate; the die upper die plate and the upper die fixed plate are both circular plate pieces, the upper die fixed plate is concentrically arranged on the lower side of the die upper die plate, a circular step structure is arranged on the lower side of the upper die fixed plate, and a multi-stage stepped hole is arranged in the center of the upper die fixed plate; the inverted pyramid pad and the male die clamping sleeve are arranged in the stepped hole in the center of the upper die fixed plate, the inner hole of the male die clamping sleeve is an inverted conical hole, the upper end of the inverted conical inner hole of the male die clamping sleeve matches the lower end step of the inverted pyramid pad, the male die elastic sleeve is arranged in the inverted conical inner hole of the male die clamping sleeve, the upper end surface of the male die elastic sleeve is in contact with the lower end surface of the inverted pyramid pad, the male die is a variable diameter rod structure with multiple stepped portions arranged on the outer edge, the male die is arranged in the central hole of the male die elastic sleeve through the upper stepped portion, the upper end surface of the male die is arranged at the center of the inverted pyramid pad, and the lower end outer diameter of the male die matches the wire harness end inner hole of the blank workpiece; the elastic upper die sleeve inner hole matches the stepped structure of the upper die fixed plate, the elastic upper die sleeve is arranged between the upper die fixed plate and the die closing plate, the upper die fixed plate and the die closing plate are connected through long bolts, the male die guide sleeve is arranged in the center of the die closing plate, and the male die is arranged in the male die guide sleeve;

[0016] The one-mold lower die assembly comprises a Haver die, a die middle ring, a die outer ring, a top piece pad, a main bearing pad, a pad plate, a die cylinder, a guide top rod and a one-mold lower die plate; the Haver die is provided with a bent inner hole for forming a blank workpiece in the center, the outer wall of the Haver die is in an inverted conical shape, and dovetail-shaped limiting convex edges are symmetrically arranged on the two side walls; the dovetail-shaped limiting convex edges are matched with dovetail grooves arranged on the inner wall of the die middle ring, the die middle ring is arranged outside the Haver die, and the die outer ring is arranged outside the die middle ring; the top piece pad is arranged in the die cylinder corresponding to the die middle ring, the top piece pad is provided with a stepped inner hole in the center, the main bearing pad is arranged in the lower hole of the stepped inner hole of the top piece pad, the lower end of the Haver die protrudes from the lower end surface of the die middle ring and is located in the upper hole of the stepped inner hole of the top piece pad, the lower end surface of the Haver die is in contact with the upper end surface of the main bearing pad, the top piece pad and the main bearing pad are arranged in the die cylinder through the pad plate arranged on the lower side, and the upper end of the die cylinder is in step cooperation with the lower end surface of the die outer ring; the die cylinder is arranged on the one-mold lower die plate through screws; and the guide top rod is in threaded connection with the lower end center of the main bearing pad after sequentially penetrating through the one-mold lower die plate and the pad plate.

[0017] Specifically, the elastic sleeve of the male die is uniformly and alternately provided with open grooves on the outer edges of both ends; and the open grooves are used for mounting and cooperating with the upper die fixing plate.

[0018] Specifically, the lower side surface of the die closing plate is provided with a stepped groove, and the upper end surface of the die outer ring is provided with a stepped part matched with the stepped groove, which is used for alignment and positioning during die closing.

[0019] Specifically, the die cylinder is provided with an opening window on the outer edge, and a connecting hole is arranged on the upper end surface of the die cylinder corresponding to the position of the opening window and on the lower end surface of the die outer ring corresponding to the position opposite to the position of the opening window, and a bolt is arranged to penetrate through the connecting hole of the die cylinder and the die outer ring from the lower end to the upper end, so as to connect the die cylinder and the die outer ring.

[0020] A composite forging forming secondary cold forging die for an integrated 90-degree joint comprises a two-mold upper die assembly and a two-mold lower die assembly.

[0021] The two-mold upper die assembly comprises a two-mold upper die plate, an upper die core, an upper die outer ring and an upper die pad plate; the two-mold upper die plate is a square plate; the upper die outer ring is arranged on the lower side of the two-mold upper die plate, the upper die outer ring is a square ring structure with an inner hole eccentric to the left, two side walls in the length direction of the square inner hole of the upper die outer ring are provided with stepped sides, a semicircular groove is arranged on the lower surface of the left side of the upper die outer ring corresponding to the middle of the width side of the left side of the inner hole, and an inner guide column hole is arranged on the diagonal position of the upper die outer ring; the upper die core is a square block structure, the upper die core is arranged between the two stepped sides in the upper die outer ring, the lower end surface of the upper die core is provided with a stepped structure corresponding to the connecting bridge of the 90-degree joint, a transition inclined surface is arranged between the stepped surfaces, and a semicircular groove concentric with the groove on the lower surface of the upper die outer ring is also arranged on the left stepped surface of the lower end surface of the upper die core; the upper die pad plate is arranged in the upper die outer ring on the upper side of the upper die core.

[0022] The lower die assembly of the double die includes a lower die core, a lower die middle ring, a lower die outer ring, a ejector, a lower die seat, a lower die middle pad, a lower die pad, a lower die plate, a lower die ejector rod, a spring, a floating lower die, and a transverse core shaft; the lower die core is a cylindrical structure with a tapered outer part, and the inner hole of the lower die core matches the outer edge of the insertion end of the workpiece; the lower die middle ring is sleeved on the outer side of the lower die core, and the upper end of the lower die middle ring is provided with a forming slope on the left side corresponding to the transition slope on the lower surface of the upper die core; the floating lower die is arranged on the left side of the lower die middle ring, and the upper surface of the floating lower die is provided with a semicircular groove corresponding to the semicircular groove on the left side of the upper die core; the wire harness end of the primary cold forging workpiece is located in the two semicircular grooves opposite to each other of the floating lower die and the upper die core, and the lower surface of the floating lower die is provided with an inner hole; the lower die outer ring is arranged on the outer side of the lower die middle ring and the floating lower die corresponding to the upper die outer ring; the left upper surface of the lower die outer ring is provided with a semicircular groove corresponding to the groove on the left lower surface of the upper die outer ring, and the diagonal position of the lower die outer ring is provided with an inner guide column; the transverse core shaft is arranged between the semicircular grooves of the lower die outer ring and the upper die outer ring, and the end of the transverse core shaft is inserted into the inner hole of the wire harness end of the primary cold forging workpiece; the lower end of the ejector is slidingly arranged in the lower die seat, and the upper end is located in the inner hole of the lower die core; the lower die seat is arranged in the lower die middle pad; the lower die middle pad is arranged on the lower side of the lower die outer ring corresponding to the shape of the lower die outer ring, and the lower die middle pad is provided with a positioning groove corresponding to the position of the floating lower die; the spring is arranged in the positioning groove, and the upper end of the spring is located in the inner hole of the floating lower die; the lower die pad is arranged between the lower die middle pad and the lower die plate; the upper end of the lower die ejector rod is slidingly arranged in the center of the lower die pad through a stepped part, and the lower end penetrates through the center of the lower die plate; and the upper end of the lower die ejector rod is arranged corresponding to the center of the ejector.

[0023] Specifically, the lower die plate and the upper die plate are further provided with an outer guide column assembly.

[0024] Specifically, the ejector is a variable-diameter rod structure, and the lower end of the ejector is slidingly arranged in the center hole of the lower die seat; the upper end of the ejector is provided with a circular-tapered limiting boss; the lower die seat is a cylindrical structure, and the center hole is a necked structure matching the lower end of the ejector.

[0025] Due to the adoption of the technical scheme as described above, the present application has the following advantages:

[0026] The present application adopts a primary cold forging die and a secondary cold forging die, and through a composite forging forming process, the workpiece is formed by punching and extrusion, and only the inner hole groove part of the insertion end needs to be supplemented by machining, and the rest is all formed by forging, so that the overall machining precision is high, the machining steps are reduced, the production efficiency is improved, and the material waste is greatly reduced. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1It is the overall schematic view of the one cold forging die of the present application.

[0028] Figure 2 It is the sectional view schematic view of the one cold forging die of the present application.

[0029] Figure 3 It is the sectional view schematic view of the one lower die assembly of the one cold forging die of the present application after the workpiece is taken out.

[0030] Figure 4 It is the schematic view of the punch elastic sleeve of the present application.

[0031] Figure 5 It is the schematic view of the harver concave die of the present application.

[0032] Figure 6 It is the overall schematic view of the two cold forging die of the present application.

[0033] Figure 7 It is the sectional view schematic view of the two cold forging die of the present application.

[0034] Figure 8 It is the schematic view of the upper die outer ring of the two cold forging die of the present application.

[0035] Figure 9 It is the schematic view of the upper die core of the two cold forging die of the present application.

[0036] Figure 10 It is the schematic view of the lower die outer ring assembly of the two cold forging die of the present application and the workpiece is installed.

[0037] Figure 11 It is the schematic view of the integral 90-degree joint of the present application.

[0038] In the figure: 1-one cold forging die, 101-one die upper die plate, 102-inverted pyramid pad, 103-upper die fixed plate, 104-punch elastic sleeve, 105-punch holding sleeve, 106-punch, 107-elastic upper die sleeve, 108-punch guide sleeve, 109-die clamping plate, 110-harver concave die, 111-concave die middle ring, 112-concave die outer ring, 113-ejector pad, 114-main bearing pad, 115-pad plate, 116-die cylinder, 117-guide ejector rod, 118-one die lower die plate;

[0039] 2-Secondary cold forging die, 201-Upper die plate, 202-Upper die core, 203-Upper die outer ring, 2031-Step side, 2032-Internal guide column hole, 204-Lower die core, 205-Lower die middle ring, 206-Lower die outer ring, 207-Top piece device, 208-Lower die seat, 209-Lower die middle pad, 210-Lower die pad, 211-Lower die plate, 212-Lower die ejector pin, 213-Spring, 214-Floating lower die, 215-Horizontal core shaft, 216-Upper die pad, 217-External guide column assembly

[0040] 3-Workpiece, 31-Wire harness end, 32-Connecting bridge, 33-Plug-in end. DETAILED DESCRIPTION

[0041] The application will be further explained in conjunction with the accompanying drawings and embodiments, which cannot limit the protection scope of the application, and the purpose of disclosing the application is to protect all technical improvements within the scope of the application.

[0042] In conjunction with the accompanying drawings Figures 1-11 The composite forging forming process of the integrated 90-degree joint is specifically as follows:

[0043] S1: Shearing blanking: according to the drawing requirements, round bar stock is used for blanking, the round bar stock has no cracks and slag on the outer circle, and the roughness is within Ra1.6;

[0044] S2: Primary cold forging: the press and the primary cold forging die 1 are used to process the wire harness end 31 inner hole, outer circle and plug-in end 33 outer circle of the blank workpiece 3;

[0045] S3: Secondary cold forging: the blank workpiece 3 after the primary cold forging is placed into the secondary cold forging die 2, and the connecting bridge 32 part between the wire harness end 31 and the plug-in end 33 is formed by using the press;

[0046] S4: Edge cutting: the edge cutting die is used to cut off the excess flash of the connecting bridge 32 part;

[0047] S5: Supplementary machining: the inner hole groove of the plug-in end 33 is machined.

[0048] The composite forging forming primary cold forging die 1 of the integrated 90-degree joint includes an upper die assembly and a lower die assembly.

[0049] The upper die assembly comprises an upper die plate 101, an inverted pyramid pad 102, an upper die fixing plate 103, a male die elastic sleeve 104, a male die clamping sleeve 105, a male die 106, an elastic upper die sleeve 107, a male die guide sleeve 108 and a die closing plate 109. The upper die plate 101 and the upper die fixing plate 103 are both circular plate parts. The upper die fixing plate 103 is concentrically arranged on the lower side of the upper die plate 101. A circular stepped structure is arranged on the lower side of the upper die fixing plate 103. A multi-stage stepped hole is arranged in the center of the upper die fixing plate 103. The inverted pyramid pad 102 and the male die clamping sleeve 105 are arranged in the stepped hole in the center of the upper die fixing plate 103. The inner hole of the male die clamping sleeve 105 is an inverted conical hole. The upper end of the inner hole of the male die clamping sleeve 105 matches the lower end step of the inverted pyramid pad 102. Open grooves are evenly and alternately arranged on the outer edges of both ends of the male die elastic sleeve 104, which are used for the installation and cooperation of the male die clamping sleeve 105 and the upper die fixing plate 103. The male die elastic sleeve 104 is arranged in the male die clamping sleeve 105 in a matched manner with the inverted conical inner hole of the male die clamping sleeve 105. The upper end surface of the male die elastic sleeve 104 is arranged in contact with the lower end surface of the inverted pyramid pad 102. The male die 106 is a variable diameter rod structure with multiple stepped portions arranged on the outer edge. The male die 106 is arranged in the central hole of the male die elastic sleeve 104 through the upper end stepped portion. The upper end surface of the male die 106 is arranged on the center of the inverted pyramid pad 102. The lower end outer diameter of the male die 106 matches the inner hole of the wire harness end 31 of the blank workpiece 3. The inner hole of the elastic upper die sleeve 107 matches the stepped structure of the upper die fixing plate 103. The elastic upper die sleeve 107 is arranged between the upper die fixing plate 103 and the die closing plate 109. The elastic upper die sleeve 107 is made of polyester rubber. The upper die fixing plate 103 and the die closing plate 109 are connected through long bolts. The male die guide sleeve 108 is arranged in the center of the die closing plate 109. The male die 106 is arranged in the male die guide sleeve 108.

[0050] The lower die assembly comprises a half-cone die 110, a middle die ring 111, an outer die ring 112, a top piece pad 113, a main bearing pad 114, a pad plate 115, a die cylinder 116, a guide top rod 117 and a lower die plate 118. The half-cone die 110 is provided with a bent inner hole for forming a blank workpiece 3 in the center, and the outer wall of the half-cone die 110 is in an inverted conical shape, and the outer wall on both sides is symmetrically provided with a dovetail-shaped limiting convex rib. The middle die ring 111 is provided with a dovetail groove matched with the limiting convex rib on the inner wall, and the middle die ring 111 is arranged outside the half-cone die 110, and the outer die ring 112 is arranged outside the middle die ring 111. The top piece pad 113 is arranged in the die cylinder 116 corresponding to the middle die ring 111, and the top piece pad 113 is provided with a stepped inner hole in the center, and the main bearing pad 114 is arranged in the stepped inner hole of the top piece pad 113, and the lower end of the half-cone die 110 protrudes from the lower end surface of the middle die ring 111 and is located in the upper hole of the stepped inner hole of the top piece pad 113, and the lower end surface of the half-cone die 110 is in contact with the upper end surface of the main bearing pad 114. The top piece pad 113 and the main bearing pad 114 are arranged in the die cylinder 116 through the pad plate 115 arranged on the lower side, and the upper end of the die cylinder 116 is stepped matched with the lower end surface of the outer die ring 112. The die cylinder 116 is arranged on the lower die plate 118 through screws. The guide top rod 117 is sequentially threaded through the lower die plate 118 and the pad plate 115 and is threadedly connected with the lower end center of the main bearing pad 114.

[0051] Preferably, a stepped groove is arranged on the lower side of the die plate 109, and a stepped part matched with the stepped groove is arranged on the upper end surface of the outer die ring 112, which is used for alignment positioning during die closing.

[0052] Preferably, a window is arranged on the outer edge of the die cylinder 116, and a connecting hole is arranged on the upper end surface of the die cylinder 116 corresponding to the position of the window and on the lower end surface of the outer die ring 112 corresponding to the position opposite to the position of the window. The die cylinder 116 and the outer die ring 112 are connected through the connecting hole of the outer die ring 112 and the window position from bottom to top through the die cylinder 116.

[0053] The assembly sequence of the upper die assembly is as follows:

[0054] (1) The inverted pyramid pad 102 is arranged in the upper die fixed plate 103, and the inverted pyramid pad 102 and the upper die fixed plate 103 are in clearance fit.

[0055] (2) The upper die fixed plate 103 and the upper die plate 101 are fixed by screws.

[0056] (3) The male die 106 is arranged in the male die elastic sleeve 104, and the male die 106 and the male die elastic sleeve 104 are in overfit.

[0057] (4) The male die elastic sleeve 104 is fixed on the upper die fixed plate 103 through the male die clamping sleeve 105.

[0058] (5) The punch guide sleeve 108 is installed into the clamping plate 109, and the punch guide sleeve 108 is in interference fit with the clamping plate 109;

[0059] (6) The center of the punch guide sleeve 108 is aligned with the punch 106, and the upper end of the elastic upper die sleeve 107 is aligned with the stepped structure of the upper die fixed plate 103. The clamping plate 109 and the elastic upper die sleeve 107 are fixed on the upper die fixed plate 103 by screws.

[0060] The assembly sequence of the upper die assembly of the first die is as follows:

[0061] (1) The gasket 115 is installed into the lower part of the die cylinder 116, and the gasket 115 is in clearance fit with the die cylinder 116. The die cylinder 116 is fixed on the lower die plate 118 of the first die by screws;

[0062] (2) The ejector gasket 113 is placed into the die cylinder 116, and the ejector gasket 113 is in clearance fit with the die cylinder 116;

[0063] (3) After the guide ejector rod 117 and the main force bearing gasket 114 are tightly fixed, they are installed into the ejector gasket 113. The combination of the guide ejector rod 117 and the main force bearing gasket 114 is in clearance fit with the ejector gasket 113;

[0064] (4) The concave die middle ring 111 and the concave die outer ring 112 are assembled, and the concave die middle ring 111 is in interference fit with the concave die outer ring 112;

[0065] (5) The concave die outer ring 112 and the concave die middle ring 111 are fixed on the die cylinder 116 by screws after being assembled;

[0066] (6) The Haver concave die 110 is installed into the concave die middle ring 111.

[0067] The working process of the one-step cold forging die 1 is as follows:

[0068] (1) After the upper die assembly of the first die and the lower die assembly of the first die are aligned by the clamping plate 109 and the concave die outer ring 112, they are concentric. The upper die assembly of the first die is fixed on the slide of the machine tool by bolts and pressure plates, and the lower die assembly of the first die is fixed on the lower die platform of the machine tool by bolts and pressure plates;

[0069] (2) Put the blank workpiece 3 of the round bar into the Haver die 110, the machine tool slide drives the upper die assembly to move downward, when the die holder 109 contacts with the upper surface of the Haver die 110, the die holder 109 is tightly pressed against the Haver die 110 under the action of the elastic upper die sleeve 107, when the slide continues to move downward, the punch 106 contacts with the blank workpiece 3 under the guiding action of the punch guide sleeve 108, and continues to press downward until the blank workpiece 3 is pressed into the bent inner hole to form the plug-in end 33, and the inner hole of the wire harness end 31 is extruded at the upper end; then the punch slide returns;

[0070] (3) When the machine tool slide returns to the safe distance position, the ejector cylinder rises to push the guide ejector rod 117 and the main bearing pad 114 upward, the Haver die 110 is ejected upward, the Haver die 110 is gradually opened to both sides in the dovetail groove of the die middle ring 111 under the action of the ejection force and the guide, the workpiece 3 after the first cold forging is taken out, the ejector cylinder resets, and the Haver die 110 resets under the weight.

[0071] A composite forging forming secondary cold forging die 2 of an integrated 90-degree joint, comprising a two-module upper die assembly and a two-module lower die assembly.

[0072] The two-module upper die assembly comprises a two-module upper die plate 201, an upper die core 202, an upper die outer ring 203 and an upper die pad 216; the two-module upper die plate 201 is a square plate; the upper die outer ring 203 is arranged on the lower side of the two-module upper die plate 201, the upper die outer ring 203 is a square ring structure with the inner hole eccentric to the left, the two sides of the square inner hole of the upper die outer ring 203 in the length direction are provided with stepped sides 2031, a semicircular groove is arranged on the middle of the left lower surface of the upper die outer ring 203 corresponding to the left width side of the inner hole, and an inner guide column hole 2032 is arranged at the diagonal position of the upper die outer ring 203; the upper die core 202 is a square block structure, the upper die core 202 is arranged between the two stepped sides 2031 in the upper die outer ring 203, the lower end face of the upper die core 202 is provided with a stepped structure corresponding to the connecting bridge 32 of the 90-degree joint, and a transition inclined surface is arranged between the stepped surfaces, and a semicircular groove concentric with the groove on the lower side of the upper die outer ring 203 is also arranged on the left stepped surface of the lower end face of the upper die core 202; the upper die pad 216 is arranged in the upper die outer ring 203 on the upper side of the upper die core 202.

[0073] The lower die assembly of the double die includes a lower die core 204, a lower die middle ring 205, a lower die outer ring 206, a ejector 207, a lower die seat 208, a lower die middle pad 209, a lower die pad 210, a lower die plate 211, a lower die ejector rod 212, a spring 213, a floating lower die 214, and a transverse core shaft 215. The lower die core 204 is a conical cylindrical structure, and the inner hole of the lower die core 204 matches the outer edge of the plug-in end 33 of the workpiece 3. The lower die middle ring 205 is sleeved on the outer side of the lower die core 204, and the upper end of the lower die middle ring 205 is provided with a forming inclined surface corresponding to the transition inclined surface of the lower surface of the upper die core 202. The floating lower die 214 is arranged on the left side of the lower die middle ring 205, and the upper surface of the floating lower die 214 is provided with a semicircular groove corresponding to the semicircular groove on the left side of the upper die core 202. The wire harness end 31 of the one-time cold forging workpiece 3 is located in the two opposite semicircular grooves of the floating lower die 214 and the upper die core 202, and the lower surface of the floating lower die 214 is provided with an inner hole. The lower die outer ring 206 is arranged on the outer side of the lower die middle ring 205 and the floating lower die 214 corresponding to the upper die outer ring 203. The upper surface of the left side of the lower die outer ring 206 is provided with a semicircular groove corresponding to the groove on the lower surface of the left side of the upper die outer ring 203, and the diagonal position of the lower die outer ring 206 is provided with an inner guide column. The transverse core shaft 215 is arranged between the two semicircular grooves of the lower die outer ring 206 and the upper die outer ring 203, and the end of the transverse core shaft 215 is inserted into the inner hole of the wire harness end 31 of the one-time cold forging workpiece 3. The lower end of the ejector 207 is slidingly arranged in the lower die seat 208, and the upper end is located in the inner hole of the lower die core 204. The lower die seat 208 is arranged in the lower die middle pad 209. The lower die middle pad 209 is arranged on the lower side of the lower die outer ring 206 corresponding to the shape of the lower die outer ring 206, and the lower die middle pad 209 is provided with a positioning groove corresponding to the position of the floating lower die 214. The spring 213 is arranged in the positioning groove, and the upper end of the spring 213 is located in the inner hole of the floating lower die 214. The lower die pad 210 is arranged between the lower die middle pad 209 and the lower die plate 211. The upper end of the lower die ejector rod 212 is slidingly arranged in the center of the lower die pad 210 through a stepped portion, and the lower end passes through the center of the lower die plate 211. The upper end of the lower die ejector rod 212 corresponds to the center of the ejector 207.

[0074] Preferably, the outer guide column assembly 217 is further arranged between the upper die plate 201 and the lower die plate 211 of the double die, which is used for positioning the upper die assembly and the lower die assembly of the double die during clamping.

[0075] Preferably, the ejector 207 is a variable diameter rod structure, and the lower end is slidingly arranged in the center hole of the lower die seat 208. The upper end of the ejector 207 is provided with a circular truncated cone limiting boss.

[0076] The assembly sequence of the upper die assembly of the double die is as follows:

[0077] (1) heating the upper mold outer ring 203 to 400°C, keeping the upper mold core 202 at room temperature, interference fitting the upper mold core 202 with the upper mold outer ring 203, and cooling to room temperature after overall assembly;

[0078] (2) placing the upper mold gasket 216 into the upper mold outer ring 203, and gap fitting the upper mold gasket 216 with the two-mold upper mold plate 201;

[0079] (3) connecting the upper mold outer ring 203 with the two-mold upper mold plate 201 by means of bolts.

[0080] The assembly sequence of the two-mold lower mold assembly is as follows:

[0081] (1) heating the lower mold outer ring 206 to 400°C, keeping the lower mold middle ring 205 at room temperature, assembling the lower mold middle ring 205 into the lower mold outer ring 206, cooling to room temperature after assembly, pressing the lower mold core 204 into the lower mold middle ring 205, taper interference fitting the lower mold core 204 with the lower mold middle ring 205, assembling the floating lower mold 214 into the lower mold outer ring 206, gap fitting, and completing the assembly of the lower mold outer ring 206 assembly;

[0082] (2) placing the spring 213 into the positioning groove of the lower mold middle gasket 209, gap fitting the lower mold seat 208 with the lower mold middle gasket 209, assembling the lower mold seat 208 into the lower mold middle gasket 209, assembling the ejector 207 into the lower mold seat 208, and completing the assembly of the lower mold middle gasket 209 assembly;

[0083] (3) assembling the lower mold ejector rod 212 into the central hole of the lower mold gasket 210;

[0084] (4) stacking the lower mold gasket 210, the lower mold middle gasket 209 assembly, and the lower mold outer ring 206 assembly in sequence on the two-mold lower mold plate 211, with the upper end of the spring 213 located in the inner hole of the floating lower mold 214, connecting the two-mold lower mold plate 211 with the lower mold outer ring 206 by means of bolts, and positioning the middle part by means of pin positioning connection.

[0085] The working process of the secondary cold forging die 2 is as follows:

[0086] (1) the two-mold upper mold assembly is reliably connected with the slider of the press through bolts and a pressing plate mechanism; the two-mold lower mold assembly is fixed on the lower mold platform of the press through bolts and a pressing plate mechanism; the two-mold upper mold assembly and the two-mold lower mold assembly are circumferentially positioned by inner guide columns, so as to ensure that no displacement occurs during upward and downward movement;

[0087] (2) Insert the transverse core shaft 215 into the wire harness end 31 of the once cold-forged workpiece 3, and insert the other end of the cold-forged workpiece 3 into the lower die core 204, and the outer edge of the wire harness end 31 is located in the semicircular groove of the floating lower die 214, and the transverse core shaft 215 is located in the semicircular groove of the lower die outer ring 206; the workpiece 3 is axially positioned by the transverse core shaft 215, so that the position of the workpiece 3 is fixed during the machining process;

[0088] (3) The press slide moves downward to drive the two-mold upper die assembly to move downward, and the upper die core 202 and the lower die core 204 in the two-mold upper die assembly, the lower die middle ring 205 and the floating lower die 214 participate in the forming process of the secondary cold forging, and during the forming process, the cylindrical part of the turning part will be flattened to become a connecting flat part, and the cylindrical part in contact with the floating lower die 214 will not participate in the deformation under the support and positioning action of the transverse core shaft 215, and only make rigid translation; when moving to the closed die state, the forming process is completed, and after the forming process is completed, the press can drive the upper die to return;

[0089] (4) After the upper die returns, the forged piece will be left in the lower die, and when the oil press lower top cylinder pushes out, it will push the lower die ejector rod 212 upward, in turn drive the ejector 207 upward, so as to drive the forged piece to separate from the lower die core 204, that is, the forged piece is taken out from the die, after the forged piece is taken out, the transverse core shaft 215 can be pulled out, and the secondary cold forging process is completed.

[0090] The part of the application not described in detail is the prior art.

[0091] The examples selected in the present text in order to disclose the inventive purpose of the present application are currently considered appropriate, but it should be understood that the present application is intended to include all variations and improvements of the examples that belong to the scope of the present concept and invention.

Claims

1. A composite forging die for an integrated 90-degree joint, characterized in that: It includes a primary cold forging die and a secondary cold forging die; the primary cold forging die includes an upper die assembly and a lower die assembly; The upper mold assembly includes an upper mold template, an inverted pyramid pad, an upper mold fixing plate, a punch elastic sleeve, a punch clamping sleeve, a punch, an elastic upper mold sleeve, a punch guide sleeve, and a mold assembly template. Both the upper mold template and the upper mold fixing plate are circular plates. The upper mold fixing plate is concentrically positioned on the lower side of the upper mold template. A circular stepped structure is concentrically positioned on the lower side of the upper mold fixing plate, and a multi-level stepped hole is located at the center of the upper mold fixing plate. The inverted pyramid pad and the punch clamping sleeve are positioned within the stepped hole at the center of the upper mold fixing plate. The inner hole of the punch clamping sleeve is an inverted conical hole, and the upper end of the inner hole of the punch clamping sleeve matches the lower end step of the inverted pyramid pad. The elastic upper mold sleeve and the punch... The inverted conical inner hole of the die clamping sleeve is matched and set inside the die clamping sleeve. The upper end face of the die elastic sleeve is in contact with the lower end face of the inverted pyramid pad. The die is a variable diameter rod structure with multiple steps on the outer edge. The die is set in the center hole of the die elastic sleeve through the upper step. The upper end face of the die is set on the center of the inverted pyramid pad. The lower end outer diameter of the die matches the inner hole of the wire harness end of the blank workpiece. The inner hole of the elastic upper die sleeve matches the stepped structure of the upper die fixing plate. The elastic upper die sleeve is set between the upper die fixing plate and the assembly plate. The upper die fixing plate and the assembly plate are connected by long bolts. The die guide sleeve is set in the center of the assembly plate. The middle part of the die passes through the die guide sleeve. The lower die assembly includes a Haval die cavity, a die cavity middle ring, a die cavity outer ring, an ejector pad, a main load-bearing pad, a pad plate, a die cylinder, a guide ejector rod, and a lower die template. The Haval die cavity has a central bending hole for forming the blank workpiece. The outer wall of the Haval die cavity is inverted conical, with dovetail-shaped limiting protrusions symmetrically arranged on both outer walls. The inner wall of the die cavity middle ring has dovetail grooves matching the limiting protrusions. The die cavity middle ring is located outside the Haval die cavity, and the die cavity outer ring is located outside the die cavity middle ring. The ejector pad is located inside the die cylinder corresponding to the die cavity middle ring. The center has a stepped inner hole, and the main load-bearing pad is set in the lower part of the stepped inner hole of the ejector pad. The lower end of the Haval die protrudes from the lower end face of the die's middle ring and is located in the upper part of the stepped inner hole of the ejector pad. The lower end face of the Haval die is in contact with the upper end face of the main load-bearing pad. The ejector pad and the main load-bearing pad are set in the mold cylinder through a pad plate set on the lower side. The upper end of the mold cylinder is engaged with the stepped lower end face of the outer ring of the die. The mold cylinder is set on the lower mold plate of the first mold by screws. The guide rod passes through the lower mold plate and the large pad in sequence and is threaded to the center of the lower end of the main load-bearing pad.

2. The composite forging die for an integrated 90-degree joint according to claim 1, characterized in that: The outer edges of both ends of the punch elastic sleeve are evenly and alternately provided with opening grooves; used for the installation and cooperation of the punch clamping sleeve and the upper mold fixing plate.

3. The composite forging die for an integrated 90-degree joint according to claim 1, characterized in that: The lower side of the mold plate is provided with a stepped groove, and the upper end of the outer ring of the die is provided with a stepped part that matches the stepped groove, for alignment and positioning during mold closing.

4. The composite forging die for an integrated 90-degree joint according to claim 1, characterized in that: The outer edge of the mold cylinder is provided with an opening, and the upper end face of the mold cylinder corresponding to the opening position is provided with a connection hole at the corresponding position on the lower end face of the outer ring of the die. The bolt passes through the connection hole between the mold cylinder and the outer ring of the die from bottom to top at the opening position to connect the mold cylinder and the outer ring of the die.

5. The composite forging die for an integrated 90-degree joint according to claim 1, characterized in that: The secondary cold forging die includes an upper die assembly and a lower die assembly. The upper mold assembly includes an upper mold template, an upper mold core, an upper mold outer ring, and an upper mold pad. The upper mold template is a square plate. The upper mold outer ring is located on the lower side of the upper mold template and is a square ring structure with its inner hole offset to the left. Stepped sidewalls are provided on both sides of the square inner hole of the upper mold outer ring along its length. A semi-circular groove is provided in the middle of the left side of the lower left surface of the upper mold outer ring corresponding to the width of the left side of the inner hole. Inner guide post holes are provided at the diagonal positions of the upper mold outer ring. The upper mold core is a square block structure and is located between the two stepped sidewalls inside the upper mold outer ring. The lower end face of the upper mold core is a stepped structure corresponding to the connecting bridge of the 90-degree joint. A transition slope is provided between the stepped surfaces. A semi-circular groove concentric with the groove on the lower side of the upper mold outer ring is also provided on the left step of the lower end face of the upper mold core. The upper mold pad is located inside the upper mold outer ring on the upper side of the upper mold core. The two-die lower die assembly includes a lower die core, a lower die middle ring, a lower die outer ring, an ejector, a lower die base, a lower die intermediate pad, a lower die pad, a two-die lower template, a lower die ejector rod, a spring, a floating lower die, and a transverse mandrel. The lower die core is a cylindrical structure with an externally conical shape, and the inner hole of the lower die core matches the outer edge of the workpiece's insertion end. The lower die middle ring is sleeved on the outside of the lower die core, and a forming slope corresponding to the transition slope of the lower surface of the upper die core is provided on the upper left side of the lower die middle ring. The floating lower die is located on the left side of the lower die middle ring, and a semi-circular groove corresponding to the semi-circular groove on the left side of the upper die core is provided on the upper surface of the floating lower die. The wire harness end of the cold-forged workpiece is located in the two semi-circular grooves corresponding to the floating lower die and the upper die core. An inner hole is provided on the lower surface of the floating lower die. The lower die outer ring is located on the outside of the lower die middle ring and the floating lower die, corresponding to the outer ring of the upper die. A forming slope corresponding to the transition slope of the lower die core is provided on the upper left side of the lower die outer ring. A semi-circular groove corresponding to the groove on the lower left side of the upper die outer ring; an inner guide post is provided at the diagonal position of the lower die outer ring; a transverse mandrel is set between two semi-circular grooves opposite to the lower die outer ring and the upper die outer ring, and the end of the transverse mandrel is inserted into the inner hole of the wire harness end of the cold forging workpiece; the lower end of the ejector is slidably set in the lower die base, and the upper end is located in the inner hole of the lower die core; the lower die base is set in the lower die intermediate pad; the lower die intermediate pad is consistent with the shape of the lower die outer ring and is set on the lower side of the lower die outer ring, and a positioning groove is set on the lower die intermediate pad corresponding to the floating lower die position; a spring is set in the positioning groove, and the upper end of the spring is located in the inner hole of the floating lower die; the lower die pad is set between the lower die intermediate pad and the second die lower template; the upper end of the lower die ejector rod is slidably set in the center of the lower die pad through the step and the lower end passes through the center of the second die lower template, and the upper end of the lower die ejector rod is set in accordance with the center of the ejector.

6. The composite forging die for an integrated 90-degree joint according to claim 5, characterized in that: An external guide post assembly is also provided between the upper template and the lower template of the second mold.

7. The composite forging die for an integrated 90-degree joint according to claim 5, characterized in that: The ejector is a variable diameter rod structure, with the lower large end slidingly disposed in the center hole of the lower mold base, and a frustum-shaped limiting boss provided at the center of the upper end of the ejector; the lower mold base is a cylindrical structure, and the center hole is configured as a narrowing structure that matches the lower end of the ejector.

8. A composite forging process using the integrated 90-degree joint composite forging die as described in any one of claims 5-7, characterized in that: The specific steps are as follows: S1: Shearing and blanking: Use round bar stock for blanking according to the drawing requirements. The outer circle of the round bar stock should be free of cracks and slag inclusions, and the roughness should be within Ra1.

6. S2: One-time cold forging: Using a press and a one-time cold forging die, the blank workpiece is machined to have the inner hole and outer circle of the wire harness end, as well as the outer circle of the plug-in end; S3: Secondary cold forging: The blank workpiece after primary cold forging is placed into the secondary cold forging mold, and the connecting bridge between the wire harness end and the plug end is formed by the press. S4: Trimming: Use a trimming die to cut off excess burrs from the connecting bridge section; S5: Additional machining: Machining the inner hole groove of the connector end.

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