A processing die for a liquid cooling plate joint and its processing technology

Abstract

The present invention discloses a liquid cooling plate joint processing die and a processing technology thereof using cold extrusion equipment. Step 1: adopting a pultrusion forming process, passing an aluminum ingot through an aluminum pultrusion forming equipment to produce a profile; Step 2: cutting the profile, placing the liquid cooling plate joint after cutting into a die of the cold extrusion equipment to process area ②; Step 3: fixing the lower half of the processed product with a special fixture for CNC numerical control machine processing, and using several types of tool heads to process the joint water nozzle; Step 4: checking the appearance of the finished product for pinching marks, scratches, etc.; Step 5: removing the processed product for degreasing and cleaning, thereby completing the production process.

Description

Technical Field

[0001] The invention relates to a processing technology for parts of a liquid cooling system of an automobile battery, and in particular to a liquid cooling plate joint processing die and a processing technology thereof. Background Art

[0002] With the rapid development of electric vehicles, the demand for liquid cooling plates for battery systems is increasing. Among them, the serpentine liquid cooling plate is an extremely important form of cold plate. It is made of a harmonica flat tube pressed into a wavy shape and then welded with a joint. One end of the joint is a flat tube hole that meets the needs of flat tube assembly and welding, and the other end is a quick-insert cylindrical structure. The dimensional accuracy and consistency of the flat tube hole of the joint are the fundamental guarantee for the welding yield. The flat tube hole structure of the joint is relatively special. It is a slender and deep horizontal groove. The current flat tube hole processing in the industry is achieved by machining, that is, customizing a special cutter head, using a special fixture for positioning and clamping, and using CNC machine tools for processing. CNC machine tools have a large workload, are time-consuming, inefficient, and expensive, and the time it takes to replace the cutter head is long, resulting in reduced production efficiency.

[0003] Changing the processing method of the flat tube hole of the connector from the original CNC to the cold extrusion process is also a process that the industry has been trying. However, in the existing cold extrusion process, the tool head is prone to locking with the workpiece during cold extrusion, resulting in tool head breakage. Similar connectors have not yet been applied to mass production cases. Therefore, it is necessary to design a liquid cooling plate connector processing mold and its processing technology to solve the above problems. Summary of the Invention

[0004] In order to solve the above technical problems, the technical solution of the present invention is: a liquid cooling plate joint processing mold and a processing technology thereof,

[0005] Step 1: Use pultrusion process to make aluminum ingots into profiles through aluminum pultrusion equipment;

[0006] Step 2: Cut the profile into pieces, and then place the liquid cooling plate joint into the cold extrusion equipment mold to perform cold extrusion on the processing area ②;

[0007] Step 3: Use the fixture to fix the semi-finished product in the processing area ②, and then fix the processing area ①

[0008] Carry out CNC machine processing and use several types of cutter heads to process the joint water nozzle part;

[0009] Step 4: Check the appearance of the finished product for any pinch marks, scratches, etc.

[0010] Step 5: Remove the joint from step 4 and perform a degreasing and cleaning process to complete the production of one joint;

[0011] The die of the cold extrusion equipment in step two includes an upper template and a lower template. The upper template and the lower template are connected by two outer guide columns. The upper template is connected to a punch through a punch fixing plate. A die backing plate is arranged on the lower template. A push plate is arranged through the inner side of the die backing plate. The push plate is arranged below the die. The interaction between the punch and the die realizes the processing of the processing area ②. Through the design of the die of the cold extrusion equipment, the processing efficiency of the liquid cooling plate joint can be increased, and the defective rate generated in the product processing can be reduced.

[0012] A further improvement of the present invention lies in that: the cold extrusion process in step two includes step S1-1: selecting materials; S1-2: softening treatment; S1-3: blanking step; S1-4: machining; S1-5: phosphating and lubricating treatment; S1-6: extrusion forming step; S1-7: T6 treatment step; S1-8: pickling step.

[0013] A further improvement of the present invention lies in that: a punch backing plate is arranged between the punch fixing plate and the upper template of the die of the cold extrusion equipment in step two. Two inner guide columns penetrating through the punch fixing plate are arranged on the lower end surface of the upper template. A punch is arranged between the two inner guide columns. A processing groove is arranged on the inner bottom surface of the die. The processing groove includes a joint groove and a drainage hole groove structure. The joint groove and the drainage hole groove structure are connected through. By arranging the processing groove and arranging the drainage hole groove structure on the processing groove, the processing material can flow inside and the fluidity of the material can be increased, so that the processing efficiency is increased. The two ends of the upper bottom surface of the drainage hole groove structure are in an inclined surface structure.

[0014] A further improvement of the present invention lies in that: the inclined surface structure is the same as the slope at both ends of the product bottom surface. The design of the same inclination can increase the processing accuracy and prevent the situation of poor processing accuracy caused by non-matching contact. Since the inclination is matched, the cold extrusion process can be carried out more smoothly, and the processing efficiency is improved.

[0015] A further improvement of the present invention lies in that: a push plate spacer is arranged below the push plate in step two. A first push plate fixing block is arranged between the push plate spacer and the push plate. A second push plate fixing block is arranged on the end surface of the push plate spacer away from the first push plate fixing block. Die fixing rings are arranged on both sides of the push plate spacer. A push rod is arranged below the second push plate fixing block. Such a structure can assist the cold extrusion process.

[0016] A further improvement of the present invention lies in that: a layer of lubricant is coated on the outer side surface of the punch. The function of coating the lubricant is to enable the punch to play a lubricating role when pressing the product to be processed downward, and can also play a role in protecting the punch, and can prevent the accumulation of effective materials at the bottom, which can improve the processing efficiency.

[0017] A further improvement of the present invention lies in that: the pressure applied downward by the punch is 40 tons. The setting of 40 tons of pressure can make the surface accuracy of the processed product relatively high and the effect of pressing and forming relatively good.

[0018] The beneficial effects of the present invention:

[0019] In the present invention, the joint nozzle part is precisely processed by a CNC numerical control machine tool, while the outer shape, inner cavity, etc. of the joint base and the processed parts of the inner and outer chamfers are completed by a cold extrusion process. By adding the cold extrusion process, the workload of precise processing by the CNC numerical control machine tool is greatly reduced, the CNC processing at the flat tube connection is reduced, the processing time of the CNC numerical control machine tool is saved. The original processing time of 150 s only requires 5 s. And through the cold extrusion process, the molecular density after extrusion is greater and the overall strength is higher, which can improve the output of the product, reduce the processing cost of the product and reduce the defective rate. For the T6 treatment, a combined electric furnace is used, in which the vibration of the workpiece is significantly reduced, and the water inlet time is also reduced from 15 seconds to 7 seconds. The hardness of the product is increased to above HB83, which better guarantees the mechanical properties of the product and effectively avoids the problem of workpiece deformation. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is the profile structure of the present invention;

[0021] Figure 2 is the liquid cooling plate joint structure of the present invention;

[0022] Figure 3 is the semi-finished product structure after cold extrusion processing of the present invention;

[0023] Figure 4 is the finished product structure of the present invention;

[0024] Figure 5 is the sectional view of the cold extrusion equipment die of the present invention;

[0025] Figure 6 is the schematic diagram of the structure of the female die of the present invention;

[0026] Figure 7 is the schematic diagram of the extrusion working of the cold extrusion equipment die of the present invention;

[0027] Figure 8 is the schematic sectional view of the drainage groove hole of the present invention;

[0028] In the figure: ① and ② are the processing areas respectively, 1 - upper template, 2 - lower template, 3 - outer guide pillar, 4 - punch fixing plate, 5 - punch, 6 - die backing plate, 7 - ejector plate, 8 - die, 9 - punch backing plate, 10 - inner guide pillar, 11 - processing groove, 12 - joint groove, 13 - drainage hole groove structure, 14 - inclined plane structure, 15 - product bottom surface, 16 - ejector plate spacer, 17 - first ejector plate fixing block, 18 - second ejector plate fixing block, 19 - die fixing ring, 20 - push rod. Specific implementation mode

[0029] The present invention provides a cold extrusion type liquid cooling plate joint processing technology. Those skilled in the art can draw on the content of this article and appropriately improve the process parameters to achieve it. It should be particularly noted that all similar substitutions and modifications are obvious to those skilled in the art, and they all belong to the protection scope of the present invention. The method and application of the present invention have been described through preferred embodiments. Relevant personnel can obviously make changes or appropriate changes and combinations to the methods and applications in this article without departing from the content, spirit and scope of the present invention to implement and apply the technology of the present invention.

[0030] A liquid cooling plate joint processing die and its processing technology. The original processing process is as follows: First, adopt the pultrusion process to make an aluminum ingot into a profile (such as Figure 1 ) through an aluminum pultrusion forming device, and then perform cutting processing on the profile (such as Figure 1 ). The liquid cooling plate joint (such as Figure 2 ) after cutting processing is placed in the die of a cold extrusion device for processing area ②. The processed product (such as Figure 3 ) is fixed at the lower part using a professional fixture for CNC machine tool processing. Several types of tool heads are used to process the joint nozzle part, and finally, the joint in the removed state (such as Figure 4 [[ID=1⑨]]) is degreased and cleaned, thus completing the production of one joint.

[0031] The processing process flow of the present invention is as follows: Step 1: Adopt the pultrusion process to make an aluminum ingot into a profile (1) through an aluminum pultrusion forming device; Step 2: Perform cutting processing on the profile (such as Figure 1 ). The liquid cooling plate joint (such as Figure 2)Place it in the mold of the cold extrusion equipment for processing area ②. The cold extrusion equipment mold includes an upper template 1 and a lower template 2. The upper template 1 and the lower template 2 are connected by two outer guide columns 3. The upper template 1 is connected to a punch 5 through a punch fixing plate 4. A die cushion plate 6 is arranged on the lower template 2. A push plate 7 is arranged through the inner side of the die cushion plate 6. The push plate 7 is arranged below a die 8. The interaction between the punch 5 and the die 8 realizes the processing of processing area ②. A punch cushion plate 9 is arranged between the punch fixing plate 4 and the upper template 1. Two inner guide columns 10 penetrating the punch fixing plate 4 are arranged on the lower end surface of the upper template 1. The punch 5 is arranged between the two inner guide columns 10.

[0032] A processing groove 11 is arranged on the inner bottom surface of the die 8. The processing groove 11 includes a joint groove 12 and a drainage hole groove structure 13. The original state mold does not design the drainage hole groove structure 13 in the middle of the processing die 11. Therefore, during extrusion, the material has nowhere to flow, which will cause the punch 5 to break. Designing the drainage hole groove structure 13 can effectively protect the punch 5. The joint groove 12 and the drainage hole groove structure 13 are connected through. The upper bottom surface of the drainage hole groove structure 13 is in a slope structure 14 at both ends. The slope structure 14 has the same slope as both ends of the product bottom surface 15. Setting the drainage hole groove structure 13 can make the processing material flow inside and increase the fluidity of the material, making the processing process more efficient and the processing flow smoother. A push plate spacer 16 is arranged below the push plate 7. A first push plate fixing block 17 is arranged between the push plate spacer 16 and the push plate 7. A second push plate fixing block 18 is arranged on the end surface of the push plate spacer 16 away from the first push plate fixing block 17. Die fixing rings 19 are arranged on both sides of the push plate spacer 16. A push rod 20 is arranged below the second push plate fixing block 18. A layer of lubricant is coated on the outer side surface of the punch 5. The function of coating the lubricant is to play a lubricating role when the punch 5 presses down the product to be processed, prevent the punch 5 from being worn, protect the punch 5, and at the same time can enhance the fluidity of the material during the cold extrusion process, prevent the situation of effective material accumulation at the bottom. During the extrusion process, the aluminum material flows up and down, which can improve the processing efficiency. The pressure applied by the punch 5 downward is 40 tons. The setting of this pressure can make the surface accuracy of the processed product higher and the pressing and forming effect better.

[0033] Step three: The processed product (such as Figure 3)Fix the lower part with a fixture for CNC machining. Use several tool heads to machine the joint nozzle part. The machining time of the tool head for the joint nozzle part is 90S; Step 4: Check the appearance of the finished product. The finished product has no cracks and the cut surface is smooth; Step 5: Remove the joint in state (4) for degreasing and cleaning, and thus complete the production of one joint.

[0034] When the liquid-cooled plate joint (2) is cold-extruded in Step 2, the machining time of the liquid-cooled plate joint (2) in the cold extrusion equipment is 5S. The original machining time by CNC is 150S. At the same time, when the joint is fixed with a professional fixture, there is a risk of clamping damage to the joint surface. The processing scheme of the present invention can reduce one fixture fixing process, and the product rejection rate here can be reduced by 50%.

[0035] The cold extrusion process in Step 2 includes Step S1-1: Select materials; S1-2: Softening treatment; S1-3: Blanking step; S1-4: Machining; S1-5: Phosphating and lubricating treatment; S1-6: Extrusion forming step; S1-7: T6 treatment step; S1-8: Pickling step; In Step S1-7, first perform quenching treatment in a solid melting furnace, keep it at a furnace temperature of 500 °C for at least 2 hours, then put it into water at 40 °C for 10 - 15 minutes after taking it out of the furnace, and then perform tempering treatment in an aging furnace, keep it at 160 °C for at least 10 hours, and air-cool it after taking it out of the furnace.

[0036] By adding the cold extrusion process, the workload of precision machining using CNC machine tools is greatly reduced, the CNC machining at the flat tube connection is reduced, the installation and disassembly of one fixture are reduced, the rejection rate is reduced by 50%, and it jointly plays a role in increasing the qualified product rate. The overall qualified product rate of the products processed according to the above processing conditions is increased by 56.4%.

[0037] The above specific embodiments have further detailed the technical problems solved, technical solutions and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A processing die for a liquid cooling plate joint, characterized in that: The processing die includes an upper template and a lower template. The upper template and the lower template are connected by two outer guide pillars. The upper template is connected to a punch through a punch fixing plate. A die backing plate is provided on the lower template. A push plate is penetrated through the inner side of the die backing plate. The push plate is arranged below the die. The interaction between the punch and the die realizes the processing of the processing area ②. A punch backing plate is provided between the punch fixing plate of the processing die and the upper template. Two inner guide pillars penetrating the punch fixing plate are provided on the lower end surface of the upper template. A punch is arranged between the two inner guide pillars. A processing groove is provided on the inner bottom surface of the die. The processing groove includes a joint groove and a drainage hole groove structure. The joint groove and the drainage hole groove structure are connected through. The upper bottom surface of the drainage hole groove structure is in an inclined surface structure at both ends. The inclined surface structure has the same slope as the slopes at both ends of the product bottom surface. A push plate spacer is provided below the push plate. A first push plate fixing block is provided between the push plate spacer and the push plate. A second push plate fixing block is provided on the end surface of the push plate spacer away from the first push plate fixing block. Die fixing rings are provided on both sides of the push plate spacer. A push rod is provided below the second push plate fixing block.

2. A processing technology for a liquid cooling plate joint, characterized in that: Step 1: Adopt a drawing and pressing forming process to make the aluminum ingot into a profile through an aluminum extrusion forming device; Step 2: Perform cutting processing on the profile. The liquid-cooled plate joint after cutting processing is placed in the processing die to perform cold extrusion process processing on the processing area ②. The processing die is the processing die of claim 1; Step 3: Use a fixture to fix the product processing area ② of the semi-finished product after processing, and then perform CNC machine tool processing on the processing area ①, and use several types of cutting tools to process the joint nozzle part; Step 4: Check whether there are scratches or nicks on the appearance of the finished product; Step 5: Remove the joint in Step 4 and perform a degreasing and cleaning process, that is, complete the production of one joint.

3. The processing technology of a liquid cooling plate joint according to claim 2, characterized in that: The cold extrusion process in Step 2 includes Step S1-1: Select materials; S1-2: Softening treatment; S1-3: Blanking step; S1-4: Machining; S1-5: Phosphating and lubricating treatment; S1-6: Extrusion forming step; S1-7: T6 treatment step; S1-8: Pickling step.

4. The processing technology of a liquid cooling plate joint according to claim 3, characterized in that: A layer of lubricant is coated on the outer side surface of the punch in Step 2.

5. The processing technology of a liquid cooling plate joint according to claim 4, characterized in that: The pressure applied by the punch downward in Step 2 is 40 tons.

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