Backpressure controllable type automobile air conditioner compressor static scroll plate forging die

Abstract

The invention discloses a back pressure controllable type automobile air conditioner compressor static scroll plate forging die which is characterized in that a forming upper die and an upper die core are connected in a hot pressing fit manner to form an upper die whole body; the lower die part comprises a forming female die, a female die sleeve, a female die prestress ring and a female die outer ring which are sequentially connected in a hot-press fit mode, and the problem of forging surface quality defects caused by unsmooth exhaust can be solved through a modular structure. The back pressure mechanism pushes the piston through the hydraulic system, back pressure is transmitted to the back pressure body through the push rod, the hydraulic system can adjust proper back pressure according to the size of the forge piece, and forge piece forming is more reliable. According to the invention, a hydraulic system is innovatively introduced, so that the back pressure has adjustable capability, the scroll plate forge piece has good contour in the axial profile, and the dimensional precision is obviously improved; and meanwhile, a modular design is adopted, so that each part is convenient to disassemble, assemble and replace, the maintenance cost is effectively reduced, and the improvement of the production efficiency and the optimization of the production cost are realized.

Description

Technical Field

[0001] This invention relates to the field of metal plastic forming technology, specifically to a back pressure controllable automotive air conditioning compressor static vortex forging die. Background Technology

[0002] Scroll compressors are used in a wide range of applications, including air conditioning, gas delivery, engine turbocharging, and vacuum systems. Their key components are the moving and stationary scroll plates, both with involute curved surfaces forming their sidewalls. During operation, the moving plate rotates and translates relative to the stationary plate, continuously completing the processes of medium intake, compression, and discharge.

[0003] Parts produced using plastic forming flow control technology not only significantly improve production efficiency and material utilization but also substantially enhance their mechanical properties. Abroad, this technology is widely used in the forming of various parts. In recent years, China has also begun to gradually introduce this technology into the forming of scroll plates.

[0004] The integrated automotive air conditioning compressor scroll back pressure forming mold and its process method proposed in patent 202311274267.5 have a simple cavity structure, which is prone to stress concentration leading to mold breakage. It also lacks exhaust space, affecting the surface quality of the scroll forging.

[0005] Patent 202110642150.2 proposes a forming mold and method for a double-sided scroll plate stationary disc of an air conditioning compressor, which adopts a two-stage forming method of pre-forging a billet and then performing a final forging by positive and negative compound extrusion. However, this design has two shortcomings: first, the two-stage forming method increases production costs and prolongs the development cycle; second, the method of using elastomer compression to provide back pressure is difficult to control precisely and cannot flexibly adjust the pressure according to the requirements of the product forming process. Summary of the Invention

[0006] The purpose of this invention is to provide a back-pressure controllable automotive air conditioning compressor static scroll forging die to solve the problems of product quality reliability during scroll forming and the short lifespan of the upper and lower dies.

[0007] The technical solution to achieve the purpose of this invention is as follows:

[0008] A back-pressure controllable automotive air conditioning compressor static scroll forging die includes: an upper die structure, a lower die structure, a back-pressure structure, and a support structure;

[0009] The bottom contour of the upper mold structure matches the outer contour of the scroll plate product, and is used to form the blank into a scroll plate product when it is closed with the lower mold structure.

[0010] The lower mold structure is provided with a vortex-shaped concave mold cavity and a spiral protrusion structure that matches the contour of the vortex disk product groove, and is provided with an exhaust structure for discharging the gas squeezed during the molding process; the lower end of the vortex-shaped concave mold cavity is provided with a hole system for placing a force transmission pin.

[0011] The support structure is used to fix the stationary components of the back pressure structure and guide the moving components;

[0012] The back pressure structure includes:

[0013] The force transmission pin is set between the back pressure pad and the back pressure body to transmit the back pressure and the material ejection thrust.

[0014] The guide ejection pad is used to support the lower mold structure and guide the force transmission pin;

[0015] Back pressure pads are used to support the force transmission pins and can slide up and down relative to the support structure.

[0016] The back pressure push rod is located between the piston and the back pressure pad, and is used to transmit the hydraulic pressure on the piston to the back pressure pad to form back pressure.

[0017] The piston, used to support the back pressure push rod, can slide upward under hydraulic pressure to provide a preset back pressure to the back pressure body;

[0018] The ejector pin, located at the lower end of the back pressure pad, can move upward to eject the formed scroll plate product out of the mold cavity of the lower mold structure.

[0019] The back pressure body is fitted with the vortex-shaped cavity of the forming die with a clearance. Its upper end face is flush with the spiral protrusion structure of the lower die structure. It can move upward under the action of back pressure to control the flow speed of the vortex blank in the vortex direction, so that the height of the formed vortex body is consistent in the extension direction. As the upper die structure moves downward, it moves downward and becomes flush with the forming die, so that the blank metal fills the cavity of the lower die structure.

[0020] The significant advantages of this invention compared to existing technologies are:

[0021] This air conditioning compressor scroll plate forming die adopts a single-stage forming technology of direct extrusion of the billet. Compared with the traditional two-stage or three-stage forming methods, it greatly simplifies the process flow and significantly improves production efficiency. Compared with ordinary dies, this solution features a modular design for the upper and lower die structures, and utilizes the assembly gaps between modules to construct an exhaust chamber. This not only improves the exhaust efficiency and structural maintainability of the die, but also reduces the replacement cost of key modules, thereby effectively improving the forming quality of the forging. Compared with traditional back-pressure structure dies, the flow speed of the scroll plate billet in the scroll direction is controlled by the force transmission method of the external hydraulic system to push the back-pressure body. This ensures that the height of each point of the final formed scroll body remains consistent in the extension direction, thereby achieving higher processing accuracy, while improving production efficiency and reducing production costs. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the upper part of the scroll stationary disc product.

[0023] Figure 2 This is a schematic diagram of the bottom of the vortex stationary disc product (forming state diagram).

[0024] Figure 3 This is a schematic diagram of the working structure of the back pressure controllable automotive air conditioning compressor stationary vortex forging die of the present invention.

[0025] Figure 4 This is a schematic diagram of the upper forming mold.

[0026] Figure 5 This is a schematic diagram of the lower mold structure.

[0027] Figure 6 This is a schematic diagram of the three-dimensional structure of the forming die.

[0028] Figure 7 This is a schematic diagram of the coordinate system for the positioning holes.

[0029] Figure 8 This is a schematic diagram of a back pressure body.

[0030] Figure 9 This is a schematic diagram of the assembly of the lower forming die and the back pressure body before forming.

[0031] Figure 10 This is a schematic diagram of the assembly of the lower forming die and the back pressure body at the end of the forming process. Detailed Implementation

[0032] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0033] Combination Figure 3This invention designs a back-pressure controllable automotive air conditioning compressor stationary scroll forging die, which can obtain forgings with good filling quality and small scroll height difference. The forging die includes an upper forming die structure, a lower die structure, a back-pressure structure, and a support structure.

[0034] Combination Figure 2 , Figure 3 and Figure 4 The upper mold structure includes an upper mold core 1, a forming upper mold 3, and an upper mold sleeve 4. The upper mold core 1 is first heat-pressed into the forming upper mold 3, and then the forming upper mold 3 is heat-pressed into the upper mold sleeve 4. The forming upper mold 3 is provided with a positioning key A2 for circumferential positioning between the forming upper mold 3 and the upper mold sleeve 4. The entire upper mold structure is ultimately fixed in the upper mold base plate of the mold frame. The bottom contour of the forming upper mold 3 matches the outer contour of the scroll plate product; this contour is a non-axisymmetric shape. To ensure circumferential positioning accuracy between the forming upper mold 3 and the upper mold sleeve 4 during assembly, the positioning keys A2 are symmetrically arranged on both sides of the forming upper mold 3. The key widths of the two positioning keys A2 are set to b and b+2 (mm) respectively, and this width difference enables unique assembly direction identification and positioning.

[0035] Combination Figure 3 and Figure 5 The lower mold structure includes a die sleeve 5, a die outer ring 7, a forming die 9, and a die prestressing ring 10. The forming die 9 is disposed within the die prestressing ring 10; the die prestressing ring 10 is located within the die outer ring 7, and the die sleeve 5 is located within the die outer ring 7, at the upper end of the forming die 9 and the die prestressing ring 10. In a specific embodiment, the die sleeve 5 has a smaller upper end and a larger lower end on the outer ring, and the die outer ring 7 has two central holes. The upper central hole is an annular hole with a smaller upper end and a larger lower end, and the lower central hole is a circular hole, forming a stepped surface between the two central holes. The die sleeve 5 is located within the upper central hole of the die outer ring 7. After the die sleeve 5 and the die outer ring 7 are assembled, the upper end is flush with the die outer ring 7, and the lower end protrudes from the upper central hole. The die prestressing ring 10 is located within the lower central hole. The assembly sequence of the lower mold structure is as follows: first, the forming die 9 and the die prestressing ring 10 are hot-pressed together; then, the die sleeve 5 and the die outer ring 7 are hot-pressed together; finally, the two sets of hot-pressed parts are hot-pressed together as a whole to complete the lower mold assembly.

[0036] Combination Figure 5The lower end of the die sleeve 5, close to the core flat plane of the central forming hole, precisely fits with the upper flat plane of the forming die 9, with only a narrow gap for air circulation between them, forming the initial communication channel of the air cavity. A 5° conical transition surface is provided between the two flat platforms at the lower end of the die sleeve 5, allowing the space at the narrow gap to naturally expand along the slope, eventually connecting with the stepped hole and the venting groove. Through the inner wall of the outer die ring 7 and the corresponding side wall of the die prestressing ring 10, together with the expanded space, a closed annular cavity is formed. The outer die ring 7 has four vertical venting grooves evenly distributed circumferentially, with the bottom of the venting grooves connecting with the stepped hole. When metal fills the cavity under high pressure, the gas originally remaining in the gap between the cavity and the material is compressed and flows towards the annular cavity along the path of least resistance, eventually being smoothly discharged through the venting grooves of the outer die ring 7.

[0037] Combination Figure 5 , Figure 6 and Figure 7 The upper surface of the forming die 9 has a complete vortex-shaped cavity, which is a continuous groove that perfectly matches the tooth shape and wall profile of the vortex disk. The curvature, width, and depth of the groove correspond one-to-one with the morphological parameters of the vortex disk product. The lower end of the cavity is also provided with a hole system to meet functional requirements, and coaxial force transmission pins A11 and B17 are installed in the hole system. The working surface of the forming die 9 is a spiral protrusion structure that matches the groove profile of the vortex disk product. The protrusion expands outward in an involute manner from the center, and the side is a smooth curved profile, which is completely complementary to the groove shape of the vortex disk product.

[0038] Combination Figure 5 , Figure 7 The hole system layout is as follows: Around the outer circumference of the vortex-shaped concave cavity, holes are evenly distributed at 45° intervals; in the inner circumference of the vortex-shaped concave cavity, the holes are arranged to conform to the direction of the vortex-shaped grooves, with the central cross-shaped reference line as a reference: two holes correspond to the transverse reference line, and four holes are distributed along the longitudinal reference line. The entire hole system contains 14 holes, precisely adapting to the functional requirements of back pressure forming, ejection, and other process steps.

[0039] Combination Figure 3 and Figure 8The back pressure structure includes a back pressure body 8, a force transmission pin A11, a material ejection pad 12, a guide pad 15, a force transmission pin B17, a back pressure block 18, a back pressure push rod 20, a material ejection pin 21, and a piston 26. The structure is arranged sequentially from bottom to top along the axial direction, with the piston 26 at the bottom. Moving upwards, the components are the back pressure push rod 20, the back pressure block 18, the force transmission pin B17, the force transmission pin A11, and the back pressure body 8. Multiple force transmission pins B17 and A11 coaxially pass through the guide pad 15 and the material ejection pad 12, ensuring tight contact between the contact surfaces of all components and guaranteeing effective axial pressure transmission. The back pressure pad 18 is disposed within the pressure block 19 and can slide up and down within the pressure block 19. A ejector pin 21 is provided at the center of its lower end, passing through the upper pad 22, the lower pad 24, and the piston support ring 28. Multiple back pressure push rods 20 at the lower end of the back pressure pad 18 pass through the upper pad 22 and the lower pad 24 and are supported on the piston 26. The piston 26 is disposed within the piston support ring 28. A piston sealing ring 27 is provided on the outer side of the mating surface between the piston 26 and the piston support ring 28, which effectively prevents gas generation during piston pushing in the hydraulic system, ensuring stable and reliable back pressure transmission. The ejector plate 12 is located at the lower end of the forming die 9 and the die prestress ring 10, and is located within the positioning sleeve 16. The guide plate 15 and the ejector plate 12 are connected by a positioning pin A13. Both have through holes corresponding to the aforementioned hole system, providing radial positioning and axial movement guidance for the force transmission pins B17 and A11. The back pressure body 8 is clearance-fitted with the forming die 9 and can slide axially to control the metal flow.

[0040] Combination Figure 3 The support structure includes a positioning sleeve 16, a pressure block 19, an upper pad 22, a lower pad 24, and a piston support ring 28. The piston support ring 28 and the lower end of the lower pad 24 are connected by screws to form a bottom assembly. The lower pad 24 is installed in the lower mold base of the mold frame, and the piston support ring 28 is connected to an external hydraulic system. The lower pad 24, the upper pad 22, and the pressure block 19 are radially positioned and connected by a positioning pin B23, and are stacked sequentially from bottom to top along the axial direction. The positioning sleeve 16 is axially positioned with the ejector plate 12 by a positioning key B14, and is hot-pressed with the guide plate 14 and the ejector plate 12, and is installed as a whole above the pressure block 19.

[0041] To facilitate understanding of the above technical solutions of the present invention, the working principle or operation method of the present invention in actual process will be described in detail below.

[0042] Its complete process includes the following steps: material cutting, shape trimming, sandblasting, graphite coating, one-time forging, T6 heat treatment, and cleaning.

[0043] During forming, the blank 6 is placed in the lower mold cavity enclosed by the forming die 9 and the die sleeve 5, with the upper end face of the back pressure body 8 flush with the volute toothed surface of the forming die 9. Driven by external power, the upper mold structure moves downward as a whole, and the bottom ends of the forming upper die 3 and the upper die core 1 begin to apply pressure to the blank 6, causing it to undergo plastic flow in the closed mold cavity and gradually fill the volute toothed cavity. As the upper mold structure continues to press down, the metal flows non-uniformly within the cavity. The metal in the area with the shorter flow path flows downward first and contacts the upper surface of the back pressure body 8 earlier. When the metal contacts the back pressure body 8, the piston 26 located below the mold outputs a preset back pressure under the drive of the hydraulic system. This force is transmitted to the back pressure pad 18 via the back pressure push rod 20, and then sequentially through the force transmission pin B17 and the force transmission pin A11, finally acting on the back pressure body 8, causing it to provide upward and controllable back pressure support to the flowing metal. As the upper mold continues to descend, the back pressure body 8, under the thrust of the flowing metal, simultaneously drives the force transmission pin A11, force transmission pin B17, back pressure pad 18, back pressure ejector rod 20, and piston 26 downwards. The metal gradually fills the remaining mold cavity between the forming die 9 and the back pressure body 8. Under real-time control of the back pressure, the metal at the bottom of each tooth groove of the scroll plate receives a balanced upward compensating force, making the height of the lower end face of the scroll section tend to be consistent, thereby effectively suppressing the thickness difference caused by uneven metal flow. The upper mold structure continues to descend to the preset position, at which point the lower end of the back pressure body 8 is completely in contact with the bottom end of the internal cavity of the forming die 9, reaching the limit position of the movement of the back pressure body 8; the piston 26, which is linked to it, descends synchronously to the bottom end of the piston support ring 28. At this point, the precision back pressure forming process of the scroll plate is completed.

[0044] After the forming process is completed, the hydraulic system stops outputting pressure, and the upper forming die moves upward and resets. At this time, the forging remains in the cavity of the forming die 9. Subsequently, the ejector device of the press is activated, driving the ejector pin 21 to push upward. By sequentially driving the back pressure pad 18, the force transmission pin B17, the force transmission pin A11, and the back pressure body 8 to move upward synchronously, the forging is finally smoothly ejected from the lower forming die component.

[0045] Employing a single-pass forging process, the tooth profile and base structure of the scroll disk can be formed in one go, avoiding the multiple positioning, heating, and mold replacements required by traditional multi-pass forming, significantly reducing mold development costs and production debugging time. The multi-structure hot-pressing design of the upper and lower forming dies significantly improves the pressure-bearing capacity of the dies, facilitates the disassembly and replacement of various components, and effectively reduces maintenance costs. The modular structure, with an annular cavity and venting groove inside the die structure, significantly improves the surface quality of the forgings and the stability and efficiency of the production process. The external hydraulic system can adjust the corresponding back pressure according to the results of the trial molding, making the forging production process more reliable.

[0046] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A forging die for a back-pressure controllable automotive air conditioning compressor stationary scroll plate, characterized in that, include: Upper mold structure, lower mold structure, back pressure structure, and support structure; The bottom contour of the upper mold structure matches the outer contour of the scroll plate product, and is used to form the blank into a scroll plate product when it is closed with the lower mold structure. The lower mold structure is provided with a vortex-shaped concave mold cavity and a spiral protrusion structure that matches the contour of the vortex disk product groove, and is provided with an exhaust structure for discharging the gas squeezed during the molding process; the lower end of the vortex-shaped concave mold cavity is provided with a hole system for placing a force transmission pin. The support structure is used to fix the stationary components of the back pressure structure and guide the moving components; The back pressure structure includes: The force transmission pin is set between the back pressure pad and the back pressure body to transmit the back pressure and the material ejection thrust. The guide ejection pad is used to support the lower mold structure and guide the force transmission pin; Back pressure pads are used to support the force transmission pins and can slide up and down relative to the support structure. The back pressure push rod is located between the piston and the back pressure pad, and is used to transmit the hydraulic pressure on the piston to the back pressure pad to form back pressure. The piston, used to support the back pressure push rod, can slide upward under hydraulic pressure to provide a preset back pressure to the back pressure body; The ejector pin, located at the lower end of the back pressure pad, can move upward to eject the formed scroll plate product out of the mold cavity of the lower mold structure. The back pressure body is fitted with the vortex-shaped cavity of the forming die with a clearance. Its upper end face is flush with the spiral protrusion structure of the lower die structure. It can move upward under the action of back pressure to control the flow speed of the vortex blank in the vortex direction, so that the height of the formed vortex body is consistent in the extension direction. As the upper die structure moves downward, it moves downward and becomes flush with the forming die, so that the blank metal fills the cavity of the lower die structure.

2. The forging die for the static scroll of the back-pressure controllable automotive air conditioning compressor according to claim 1, characterized in that, The pore layout is as follows: The outer contour of the vortex-shaped concave model cavity has holes evenly distributed at 45° intervals; the inner contour of the vortex-shaped concave model cavity is laid out with reference to the central cross datum line: the horizontal datum line corresponds to 2 holes, and the vertical datum line distributes 4 holes.

3. The forging die for the back-pressure controllable automotive air conditioning compressor stationary scroll plate according to claim 1, characterized in that, The lower mold structure includes a die sleeve, a die outer ring, a forming die, and a die prestressing ring; the forming die is disposed inside the die prestressing ring; the die prestressing ring is located inside the die outer ring, and the die sleeve is located inside the die outer ring and at the upper end of the forming die and the die prestressing ring.

4. The forging die for the back-pressure controllable automotive air conditioning compressor stationary scroll plate according to claim 3, characterized in that, The outer ring of the die sleeve is smaller at the upper end and larger at the lower end. The outer ring of the die sleeve has two central holes. The upper central hole is an annular hole with a smaller upper end and a larger lower end, and the lower central hole is a circular hole. A stepped surface is formed between the two central holes. The die sleeve is located in the upper central hole of the outer ring of the die sleeve. After the die sleeve and the outer ring of the die sleeve are assembled, the upper end is flush with the die sleeve and the lower end protrudes from the upper central hole. The outer ring of the die sleeve has multiple vertical venting grooves evenly distributed along the circumference. The bottom of the venting grooves is connected to the stepped hole. The die prestressing ring is located in the lower central hole. Only a gap for air circulation is reserved between the lower end of the die sleeve and the upper end of the forming die. The lower end of the die sleeve has a tapered transition surface that is connected to the stepped hole.

5. The forging die for the back-pressure controllable automotive air conditioning compressor static scroll plate according to claim 3, characterized in that, The assembly sequence of the lower mold structure is as follows: first, the forming die and the die prestressing ring are hot-pressed together to form a set of hot-pressed fitting parts; then, the die sleeve and the die outer ring are hot-pressed together to form another set of hot-pressed fitting parts; finally, the two sets of hot-pressed fitting parts are hot-pressed together to complete the assembly of the lower mold.

6. The forging die for the static scroll of the back-pressure controllable automotive air conditioning compressor according to claim 1, characterized in that, The upper mold structure includes an upper mold core, a forming upper mold, and an upper mold sleeve; the upper mold core is hot-pressed into the forming upper mold, and then the forming upper mold is hot-pressed into the upper mold sleeve. The forming upper mold is provided with a positioning key A for circumferential positioning between the forming upper mold and the upper mold sleeve; the positioning key A is symmetrically arranged on both sides of the forming upper mold, and the key width of the positioning key A on both sides is different.

7. The forging die for the static scroll of the back-pressure controllable automotive air conditioning compressor according to claim 1, characterized in that, The support structure includes a positioning sleeve, a pressure block, an upper pad, a lower pad, and a piston support ring; the piston support ring is fixed to the lower end of the lower pad to form a bottom assembly; the piston support ring is connected to an external hydraulic system; the lower pad, upper pad, and pressure block are radially positioned and connected by positioning pins, and are stacked sequentially from bottom to top along the axial direction; the positioning sleeve is axially positioned with the ejector plate by positioning key B, and is hot-pressed with the guide plate and ejector plate, and is installed as a whole above the pressure block.

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