A continuous die flangeless stretch-drawing process for a transmission end cover

Abstract

A continuous die flange stretching blanking process of a transmission end cover, through the improvement of the traditional process, the cutting which is originally the last step is improved before the drawing step through the design of the cutting die. Or is the cutting of the annular thin wall area, which can easily separate synchronously during drawing. Or through the springback design of the cutting die, the completely cut disc-shaped product is pushed back to the strip clamping. In addition, during the drawing process, the tearing surface is bent towards the axial direction, the tearing surface is changed into the axial port end surface, and the new outer circumferential surface without tearing surface is formed. The process setting of the present application eliminates the traditional process setting method of flange, the redundant work steps after stamping and polishing, significantly simplifies the process steps, and improves the economic benefits of enterprises.

Description

Technical Field

[0001] This invention relates to the field of automotive parts manufacturing technology, specifically to a continuous in-mold flangeless stretching and blanking process for transmission end caps. Background Technology

[0002] A gearbox, also known as a transmission, is an automotive component used to change the speed and torque from the engine and to change the transmission ratio between the output and input shafts in a fixed or progressively increasing manner. A gearbox consists of a transmission mechanism and a control mechanism. Some cars also have a power output mechanism. Gearboxes can be classified as stepped, continuously variable, or combined types, and have functions such as reversing, interrupting power transmission, and changing the transmission ratio.

[0003] The product manufactured by the process of this application is an end cover (plug or housing) used in the transmission controller. In the production schedule of this end cover product, there are very high standard requirements for the surface roughness of the outer peripheral surface of the end cover, because the outer peripheral surface of the end cover needs to be sealed in the transmission.

[0004] The traditional manufacturing process for this end cap involves a multi-stage stamping process using a continuous die.

[0005] Traditional progressive die stamping process, see instruction manual attached. Figure 1 As shown, a cold stamping die is used to complete multiple stamping processes simultaneously at several different stations on a single die using strip stamping raw materials. Each time the die completes a stamping operation, the strip moves a fixed distance once until the product is finished.

[0006] The process includes shaping processes such as blanking, punching, marking, bending, and shaping. The final step involves cutting off the connection between the end cap and the strip through punching, thus separating the blank and obtaining a complete product.

[0007] The problems with the existing technology are: 1. In the last step of the continuous die cutting process, the mold is used to separate the forming end cap from the material strip by stamping. Since the end cap of this application has a sealing requirement on the outer peripheral surface, in the traditional process, a flange structure 8 is set between the material strip and the end cap as an intermediate transition material. In this way, when cutting, the flange part can be cut, leaving a certain amount of allowance for the outer peripheral surface of the end cap to protect the outer peripheral surface.

[0008] If this flange structure 8 is not installed, it needs to be cut directly at the edge of the outer circumference of the end cover, as per the instruction manual. Figure 2 As shown, due to the thin-walled structure of the end cap, cutting directly on the outer peripheral surface will result in a torn end face, which will severely damage the outer peripheral surface and have a negative effect on the sealing fit of the end cap product.

[0009] However, the flange design also introduces process issues. The excess material left on the outer circumference during cutting means that the outer circumference of the end cap needs to be polished after blanking, adding an extra step to the overall production process, reducing production efficiency and increasing production costs. This disadvantage is particularly pronounced in large-scale production processes such as stamping.

[0010] Therefore, improving the traditional continuous die stamping process for end caps, eliminating the reliance on the strip flange structure, and eliminating the grinding step of removing flange allowance after blanking, has real economic benefits. Summary of the Invention

[0011] In order to overcome the shortcomings of the above-mentioned technology, the present invention provides a continuous in-mold flangeless stretching and blanking process for gearbox end caps, which eliminates the dependence on the material strip flange structure and eliminates the grinding step of removing flange allowance after blanking.

[0012] The technical solution of the present invention: a flangeless stretching and blanking process for a continuous die for a transmission end cover, comprising the following steps: S1 Blanking, feeding the strip into the continuous die;

[0013] S2 forming involves stamping a strip of material at the first station of the mold to form a disc-shaped product with a central recess and radial side wings, and then moving the strip to the second station.

[0014] S3 cut: At the second station, a cut is punched around the edge contour of the radial side wing. This cut creates an annular thin-walled area between the disc-shaped product and the strip. The annular thin-walled area forms the radial outer circumferential surface of the radial side relative to the sidewall of the radial side wing. Then the strip is moved to the third station.

[0015] In the S4 deep drawing and flanging separation process, at the third station, the material strip is fixed and the radial side wing is drawn simultaneously to separate the disc-shaped product from the material strip. The radial outer circumferential surface of the radial side wing serves as the tearing surface during separation. During the deep drawing process, it undergoes a flanging motion that bends axially, and the tearing surface transforms into the axial end face. The outer part of the radial side wing is bent and flanged, and through deep drawing, a new outer circumferential surface of the end cap is formed, thus completing the end cap product forming.

[0016] Using the above technical solution, by making a cut in step S3 before stretching in step 4, the product and the strip in the disc shape form a thin-walled annular area. Because the thickness of this area is less than that of other parts of the strip after being stamped, it forms a weaker part that is more easily torn, and it continues to maintain its connection with the strip and can move with the strip.

[0017] In step S4, the material strip is fixed and the radial side wing is simultaneously drawn to separate the disc-shaped product from the material strip. While the product is separated from the material strip, the disc-shaped product is drawn to make the tear surface bend axially from the original outer peripheral surface, thus transforming the tear surface into the axial end face.

[0018] This process allows the tear surface, which originally affected the sealing fit of the product's outer peripheral surface, to be bent axially and become a port end face that does not affect the sealing fit of the product's outer peripheral surface. This one-time molding eliminates the need for grinding after product separation, and the dimensional accuracy and roughness of the outer peripheral surface can be directly achieved by stamping.

[0019] Since there is no need to worry about the allowance of the tear surface, there is no need to install a flange.

[0020] A further feature of the present invention: In step S3, a cutting mold is provided at the second station. The cutting mold includes a first punch and a first die. The first punch includes a first outer mold part, a side wing fixing part, and a core rod. The side wing fixing part has a fixing end face that fits with the radial side wing part. The side wing fixing part is inserted into the first outer mold part for coaxial fitting. The side wing fixing part has a central hole corresponding to the central recessed part. The core rod is inserted into the central hole for coaxial fitting. The core rod has a contact end face that fits with the central recessed part.

[0021] The first die includes a second outer die, a first relief member and an elastic reset member. The second outer die and the first outer die are symmetrically arranged on both ends of the strip and clamp and fix the strip along the edge contour surrounding the radial side wing. The first relief member is inserted into the second outer die for coaxial fitting. The first relief member has a recessed end face that is adapted to the shape of the disc-shaped product.

[0022] The side wing fixing member, core rod and first retraction member move synchronously to separate the disc-shaped product from the material strip, and the elastic reset member drives the first retraction member to push the disc-shaped product back into the strip.

[0023] Using the above technical solution, the cutting die is configured with a second outer mold component symmetrically positioned on both ends of the strip, and clamps and fixes the strip along the edge contour surrounding the radial side wings. This allows the side wing fixing component, core rod, and first retraction component to move synchronously, separating the disc-shaped product from the strip.

[0024] At this point, the disc-shaped product is completely cut off before stretching in step S4, eliminating the need for simultaneous cutting during the final stretching process. This simplifies the drawing process and further ensures the quality of the cut.

[0025] After complete cutting, the compression of the elastic reset member by the first retracting member during its movement causes the elastic reset member to recover its deformation potential energy, driving the first retracting member to push the disc-shaped product back into the strip. Once pushed back into the strip, it is in a locked position with the strip and can be carried by the strip to the next station.

[0026] The elastic reset element can be set as a spring.

[0027] A further feature of the present invention: In step S4, the third station is provided with a drawing die, which includes a second punch and a second die. The second punch includes a limiting cylinder and a top piece. The radial side wing includes a bent portion adjacent to the tear surface and a stationary portion adjacent to the central recess. The top piece is inserted into the limiting cylinder for coaxial fitting and includes a second recess adapted to the central recess and a first moving end face extending to the stationary end.

[0028] The second die includes a deformable cylinder and a second relief member. The second relief member is inserted into the deformable cylinder and coaxially fitted. It has a protrusion that matches the central recess and a second push end face that extends to the stationary end.

[0029] The top piece and the deformable cylinder are coaxially arranged. A gap is provided between the outer diameter of the top piece and the inner diameter of the deformable cylinder for local stretching during bending. The port of the deformable cylinder is provided with a deformation chamfer corresponding to the bending area.

[0030] Using the above technical solution, the bent portion of the radial side wing is guided to bend axially through the set deformation chamfer structure, and enters the gap set between the outer diameter of the top part and the inner diameter of the deformed cylinder for stretching of the bent portion, thereby completing the stretching and forming the final molded product.

[0031] A further feature of the present invention is that the top member and the second retractor are each provided with an adjustment hole and an adjustment rod at the corresponding central recess position. The adjustment rod is inserted into the adjustment hole and abuts against the central recess.

[0032] By adopting the above technical solution, the adjustment hole and adjustment rod are set to realize the function of adjusting the central recess of the mold.

[0033] A further feature of the present invention is that a shaping step S2.5 is provided between steps S2 and S3. Between the second station and the third station, a plurality of shaping molds are provided, and the plurality of shaping molds gradually shape the disc-shaped product to a qualified size.

[0034] Using the above technical solution, the disc-shaped product is gradually shaped to the qualified size through the set shaping mold.

[0035] The beneficial effects of this invention are as follows: By improving the traditional process, the cutting step, which was originally the final step, is now performed before the deep drawing step through the design of the cutting die. Alternatively, by utilizing the cutting of an annular thin-walled area, easy and simultaneous separation can be achieved during deep drawing. Or, through the springback design of the cutting die, the completely cut disc-shaped product is pushed back to the material strip clamping position.

[0036] Furthermore, during the deep drawing process, the torn surface is bent axially and then turned into an axial end face, cleverly forming a new outer peripheral surface without a torn surface.

[0037] The process of this invention eliminates the unnecessary steps of setting up flanges and grinding after stamping, which is common in traditional processes. This significantly simplifies the process and improves the economic benefits for enterprises. Attached Figure Description

[0038] Figure 1 A schematic diagram of the traditional process;

[0039] Figure 2 This is a schematic diagram of the tear surface in a traditional process;

[0040] Figure 3 The continuous module structure of this invention Figure 1 ;

[0041] Figure 4 The continuous module structure of this invention Figure 2 ;

[0042] Figure 5 The continuous module structure of this invention Figure 3 ;

[0043] Figure 6 This is a structural diagram of the end cap product according to an embodiment of the present invention.

[0044] Among them, 1-material strip, 21-central recess, 22-radial side wing, 221-bent part, 222-stationary part, 23-annular thin-walled area, 24-tear surface, 25-axial port end face, 26-new outer peripheral surface, 3-progressive die, 4-first punch, 41-first outer die, 42-side wing fixing part, 43-core rod, 5-first die cavity, 51-second outer die, 52-first relief part, 6-second punch, 61-limiting cylinder, 62-ejector, 7-second die cavity, 71-deformed cylinder, 72-second relief part, 73-gap, 74-deformed chamfer, 75-adjusting ejector rod, 8-flange structure. Detailed Implementation

[0045] The invention will now be described in detail with reference to the accompanying drawings, such as... Figure 1-6 As shown,

[0046] A flangeless stretching and blanking process for a transmission end cover in a continuous die 3 includes the following steps: S1 Blanking, feeding the material strip 1 into the continuous die 3;

[0047] S2 forming involves stamping the material strip 1 at the first station of the mold to form a disc-shaped product with a central recess 21 and radial side wings 22, and then moving the material strip 1 to the second station.

[0048] S3 cut, at the second station, a cut is punched around the edge contour of the radial side wing 22. This cut creates an annular thin-walled region 23 between the disc-shaped product and the strip. The annular thin-walled region 23 forms the radial outer circumferential surface of the radial side relative to the side wall of the radial side wing 22. Then the strip 1 is moved to the third station.

[0049] In the S4 deep drawing and flanging separation process, at the third station, the material strip 1 is fixed and the radial side wing 22 is drawn simultaneously to separate the disc-shaped product from the material strip 1. The radial outer peripheral surface of the radial side wing 22 serves as the tear surface 24 during separation. During the deep drawing process, it undergoes a flanging motion that bends axially. The tear surface 24 transforms into the axial end face 25, while the outer part of the radial side wing 22 is bent and flanged. Through deep drawing, a new outer peripheral surface 26 of the end cap is formed, and the end cap product is completed.

[0050] By making cuts in step S3, before stretching in step 4, the disc-shaped product and the strip 1 only form an annular thin-walled area 23. This area, due to being stamped, has a thickness less than other parts of the strip 1, forming a weaker part that is more easily torn, and continues to maintain its connection with the strip 1, and can move with the strip 1.

[0051] In step S4, the material strip 1 is fixed and the radial side wing 22 is drawn in parallel to separate the disc-shaped product from the material strip 1. While the product is separated from the material strip 1, the disc-shaped product is drawn in parallel to make the tear surface 24 bend axially from the original outer peripheral surface and transform the tear surface 24 into the axial end face 25.

[0052] This process allows the tear surface 24, which originally affected the sealing fit of the outer peripheral surface of the product, to be bent axially and become a port end face that does not affect the sealing fit of the outer peripheral surface of the product. With this one-time molding, the product does not need to be polished after separation, and the dimensional accuracy and roughness of the outer peripheral surface can be directly achieved by stamping.

[0053] Since there is no need to worry about the allowance of the tear surface 24, there is no need to install a flange.

[0054] In step S3, a cutting mold is set at the second station. The cutting mold includes a first punch 4 and a first die 5. The first punch 4 includes a first outer mold part 41, a side wing fixing part 42, and a core rod 43. The side wing fixing part 42 has a fixing end face that fits with the radial side wing part 22. The side wing fixing part 42 is inserted into the first outer mold part 41 for coaxial fitting. The side wing fixing part 42 has a central hole corresponding to the central recess 21. The core rod 43 is inserted into the central hole for coaxial fitting. The core rod 43 has a contact end face that fits with the central recess 21.

[0055] The first die 5 includes a second outer die 51, a first relief member 52 and an elastic reset member. The second outer die 51 and the first outer die 41 are symmetrically arranged on both ends of the strip 1 and clamp and fix the strip along the edge contour surrounding the radial side wing 22. The first relief member 52 is inserted into the second outer die 51 for coaxial fitting. The first relief member 52 has a recessed end face that matches the shape of the disc-shaped product.

[0056] The side wing fixing member 42, the core rod 43 and the first retracting member 52 move synchronously to separate the disc-shaped product from the material strip. The elastic reset member drives the first retracting member 52 to push the disc-shaped product back into the strip.

[0057] The cutting die is configured such that the second outer mold 51 and the first outer mold 41 are symmetrically arranged on both ends of the strip 1, and clamp and fix the strip along the edge contour surrounding the radial side wing 22. This allows the side wing fixing member 42, the core rod 43, and the first retracting member 52 to move synchronously, separating the disc-shaped product from the strip.

[0058] At this point, the disc-shaped product is completely cut off before stretching in step S4, eliminating the need for simultaneous cutting during the final stretching process. This simplifies the drawing process and further ensures the quality of the cut.

[0059] After complete cutting, the compression of the elastic reset member by the first retractor 52 during its movement causes the elastic reset member to recover its deformation potential energy, driving the first retractor 52 to push the disc-shaped product back into the strip. After being pushed back into the strip 1, it is in a locked state with the strip 1 and can be carried by the strip 1 to the next station.

[0060] The elastic reset element can be set as a spring.

[0061] In step S4, the third station is provided with a drawing die, which includes a second punch 6 and a second die 7. The second punch 6 includes a limiting cylinder 61 and a top member 62. The radial side wing 22 includes a bent portion 221 adjacent to the tear surface 24 and a stationary portion 222 adjacent to the central recess 21. The top member 62 is inserted into the limiting cylinder 61 for coaxial fitting, including a second recess adapted to the central recess 21 and a first moving end face extending to the stationary end.

[0062] The second die 7 includes a deformable cylinder 71 and a second relief member 72. The second relief member 72 is inserted into the deformable cylinder 71 and coaxially fitted. It has a protrusion portion adapted to the central recess 21 and a second push end face extending to the stationary end.

[0063] The top member 62 is coaxially arranged with the deformable cylinder 71. A gap 73 is provided between the outer diameter of the top member 62 and the inner diameter of the deformable cylinder 71 for stretching the bending section 221. The port of the deformable cylinder 71 is provided with a deformation chamfer 74 corresponding to the bending section 221.

[0064] By using the deformable chamfer 74 structure, the bent portion 221 of the radial side wing 22 is guided to bend axially and enters the gap 73 between the outer diameter of the top member 62 and the inner diameter of the deformable cylinder 71 for stretching the bent portion 221, thus completing the stretching and forming the final molded product.

[0065] The top member 62 and the second retracting member 72 are each provided with an adjustment hole and an adjustment rod 75 at the position corresponding to the central recess 21. The adjustment rod 75 is inserted into the adjustment hole and abuts against the central recess 21.

[0066] The adjustment hole and adjustment rod 75 are used to adjust the central recess 21 of the mold.

[0067] Between steps S2 and S3, there is a shaping step S2.5. Between the second station and the third station, there are several shaping molds. These shaping molds gradually shape the disc-shaped product to the qualified size.

[0068] By using the set shaping mold, the disc-shaped product is gradually shaped to the qualified size.

[0069] By improving traditional processes, the cutting step, originally the final step, is now performed before the deep drawing step through the design of the cutting die. Alternatively, the cutting of the annular thin-walled region 23 can be used to allow for easy and simultaneous separation during deep drawing. Or, the springback design of the cutting die can push the completely cut disc-shaped product back to the material strip 1 for engagement.

[0070] Furthermore, during the deep drawing process, the torn surface 24 is bent axially and then turned into the axial end face 25, thus cleverly forming a new outer peripheral surface without the torn surface 24.

[0071] The process of this invention eliminates the unnecessary steps of setting up flanges and grinding after stamping, which is common in traditional processes. This significantly simplifies the process and improves the economic benefits for enterprises.

[0072] The above embodiments are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Various modifications made by those skilled in the art based on the technical solutions of the present invention without departing from the design concept of the present invention should fall within the scope of protection defined by the claims of the present invention.

Claims

1. A progressive die flange stretch under process for a transmission end cover characterized by: The method comprises the following steps: S1, blanking, feeding the strip into a continuous die; S2, forming, stamping the strip in the first station of the die to form a disc-shaped product with a central recess and radial side wings, and then moving the strip to the second station; S3, cutting, cutting a notch around the edge profile of the radial side wings in the second station, the notch forming an annular thin-walled area between the disc-shaped product and the strip, and the annular thin-walled area forming a radial outer circumferential surface of the radial side wings relative to the side wall of one side of the radial side wings, and then moving the strip to the third station; S4, deep drawing and flanging separation, fixing the strip in the third station, and synchronously deep drawing the radial side wings to separate the disc-shaped product from the strip, the radial outer circumferential surface of the radial side wings serving as a tearing surface during separation, the radial outer circumferential surface being bent to form a flange during deep drawing, the tearing surface being changed into an axial port end surface, and the radial side wings being partially pressed and bent on the outside of the flange to form a new outer circumferential surface of the end cover through deep drawing, and the end cover product being formed.

2. A continuous die for cold extrusion forming process of a brake shoe of an automobile as claimed in claim 1, wherein: In the step S3, the second station is provided with a cutting die, the cutting die comprising a first punch and a first die, the first punch comprising a first outer die, a side wing fixing member, and a core rod, the side wing fixing member being provided with a fixed end surface matched with the radial side wings, the side wing fixing member being coaxially inserted into the first outer die, the side wing fixing member being provided with a center hole corresponding to the position of the central recess, and the core rod being coaxially inserted into the center hole, the core rod being provided with an abutting end surface matched with the central recess; the first die comprising a second outer die, a first retreat member, and an elastic reset member, the second outer die being symmetrically arranged at both ends of the strip relative to the first outer die, and clamping and fixing the strip along the edge profile around the radial side wings, the first retreat member being coaxially inserted into the second outer die, the first retreat member being provided with a recessed end surface matched with the shape of the disc-shaped product; the side wing fixing member, the core rod, and the first retreat member being synchronously moved to clamp and separate the disc-shaped product from the strip, and the elastic reset member driving the first retreat member to push the disc-shaped product back into the strip.

3. The transfer mold of claim 2, wherein: In the step S4, the third station is provided with a deep drawing die, the deep drawing die comprising a second punch and a second die, the second punch comprising a limiting cylinder member and a top member, the radial side wings comprising a curved portion adjacent to the tearing surface and a stationary portion adjacent to the central recess, the top member being coaxially inserted into the limiting cylinder member, the top member comprising a second recess matched with the central recess and a first top driving end surface extending to the stationary end portion; the second die comprising a deformation cylinder member and a second retreat member, the second retreat member being coaxially inserted into the deformation cylinder member, the second retreat member being provided with a protruding portion matched with the central recess and a second top driving end surface extending to the stationary end portion; the top member and the deformation cylinder member being coaxially arranged, a gap being formed between the outer diameter of the top member and the inner diameter of the deformation cylinder member for stretching the curved portion, and the deformation cylinder member being provided with a deformation chamfer corresponding to the curved portion.

4. The transfer mold of claim 3 wherein: the top member and the second retreat member being provided with an adjusting hole and an adjusting top rod corresponding to the position of the central recess, the adjusting top rod being inserted into the adjusting hole and abutting against the central recess.

5. A continuous die for cold extrusion forming process of a brake shoe of an automobile as claimed in claim 1, wherein: The step S2 and S3 are provided with a step S2.5 shaping, between the second station and the third station, a plurality of shaping molds are arranged, and the plurality of shaping molds gradually shape the disc-shaped product to the qualified size.

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