Microstructured electrochemical machining apparatus and method for microchannel floor and sidewall

Abstract

The application discloses a kind of microchannel bottom and side wall microstructure electrolytic machining device and method, it is related to electrolytic machining technical field, including cathode tool and workpiece, the workpiece circumscribes power supply anode, and multiple microchannels are set on the workpiece, electrolyte is passed into in the microchannel;The cathode tool circumscribes power supply cathode, and the cathode tool has the same number of machining blade as the microchannel, and the machining blade is equipped with the microstructure machining part of convex outside;The machining blade extends in corresponding microchannel, and the inner bottom and two inner side walls of microchannel can be electrolytic machined to form microstructure simultaneously.The electrolytic machining method of the microchannel bottom and side wall microstructure electrolytic machining device of the application can process the microstructure of microchannel inner bottom surface and side surface simultaneously, so that the microstructure processing efficiency in microchannel is high, and microchannel heat exchange effect is good.

Description

Technical Field

[0001] The present invention relates to the technical field of electrolytic machining, in particular to a device and method for electrolytic machining microstructures of a microchannel bottom and sidewalls. Background Art

[0002] Currently, microchannel heat sinks are widely used in a variety of applications, such as electronic devices, automotive heat exchangers, batteries, and aerospace. However, with technological advancements and increasing demand, heat dissipation capacity is facing increasing challenges. This limits the product design of traditional straight microchannel heat sinks and requires more advanced manufacturing techniques and the design of heat sink microchannels with even higher heat dissipation capacity. In recent years, to enhance heat transfer within the flow channel, researchers have optimized the microchannel structure. Commonly used in engineering, structures such as protrusions, pits, and grooves are designed on the bottom surface of the microchannel. Research has shown that the presence of these microstructures within the microchannel increases the effective heat transfer area, disrupts the boundary layer, and effectively improves the heat dissipation capacity of the heat exchanger. If corresponding microstructures are also added to the sidewalls of the microchannel, the heat transfer capacity of the microchannel can be further enhanced. However, such designs are limited by current manufacturing capabilities. The fabrication of heat transfer-enhancing microstructures within the microchannel currently involves micro-milling and laser machining. These processes are not only prone to residual stress, but also have low processing efficiency, prone to tool wear, and high processing costs. They are not suitable for, or even difficult to achieve, the fabrication of microstructures on the bottom and sidewalls of the microchannel.

[0003] Electrolytic machining (ECM) removes material based on the principle of electrochemical dissolution of metal anodes. It offers advantages such as zero tool cathode wear, high machining efficiency, no material hardness limitations, no residual stress, and excellent surface quality. It offers significant advantages when machining microstructures that enhance heat transfer within microchannels. Traditional ECM processes only in one direction and one plane, effectively machining only one microchannel surface at a time, resulting in low machining efficiency.

[0004] Therefore, it is urgent to design a device for simultaneous electrolytic processing of the bottom and side surfaces of a microchannel, so as to process the microstructures at the bottom and side walls of the microchannel at one time, thereby improving the microstructure manufacturing efficiency of the microchannel. Summary of the Invention

[0005] The purpose of the present invention is to provide a device and method for electrolytic processing of microstructures on the bottom and side walls of a microchannel to solve the problems existing in the above-mentioned prior art. The device and method can simultaneously process the microstructures on the bottom and side surfaces of the microchannel, so that the microstructure processing efficiency in the microchannel is high and the heat exchange effect of the microchannel is good.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] The present invention provides a device for electrolytically processing microstructures of a microchannel bottom and sidewalls, comprising:

[0008] A workpiece, the workpiece is connected to a positive electrode of an external power supply, and the workpiece is provided with a plurality of microchannels, wherein the microchannels are filled with electrolyte;

[0009] A cathode tool is externally connected to the negative pole of a power supply, and has machining edges with the same number as the microchannels, and the machining edges are provided with protruding microstructure machining portions; the machining edges extend into the corresponding microchannels and can simultaneously electrolytically machine the inner bottom and two inner side walls of the microchannel to form a microstructure.

[0010] Optionally, the cathode tool includes an active cathode tool, a left driven cathode tool and a right driven cathode tool; the processing blade includes an active cathode processing blade, a left driven cathode processing blade and a right driven cathode processing blade; a plurality of the active cathode processing blades are evenly arranged on the bottom of the active cathode tool, and the bottom of the active cathode processing blade is provided with the protruding microstructure processing portion; a plurality of the left driven cathode processing blades are evenly arranged on the bottom of the left driven cathode tool, and the left side of the left driven cathode processing blade is provided with the protruding microstructure processing portion; a plurality of the right driven cathode processing blades are evenly arranged on the bottom of the right driven cathode tool, and the right side of the right driven cathode processing blade is provided with the protruding microstructure processing portion.

[0011] Optionally, the left driven cathode tool includes a left driven block, the bottom of the left driven block is connected to a left bottom plate extending to the right, the left bottom plate is provided with a first hole with the same number as the left driven cathode machining edge, the left driven cathode machining edge is located at the bottom of the left bottom plate, and the right side surface of the left driven cathode machining edge and the left side wall of the corresponding first hole are located on the same plane; the right driven cathode tool includes a right driven block, the bottom of the right driven block is connected to a right bottom plate extending to the left, the right bottom plate is provided with a first hole with the same number as the right driven cathode machining edge A second hole with the same number of processing edges, the right driven cathode processing edge is located at the bottom of the right base plate, and the left side of the right driven cathode processing edge is located on the same plane as the right side wall of the corresponding second hole; the active cathode processing edge passes through the corresponding second hole and the first hole and extends into the corresponding microchannel, and the right driven cathode processing edge passes through the corresponding first hole and extends into the corresponding microchannel, and in each of the microchannels, a left cathode processing edge, an active cathode processing edge and a right cathode processing edge are provided in sequence from left to right.

[0012] Optionally, the inner side walls of the left follower block and the right follower block are both inclined structures that gradually tilt inward from top to bottom, and both sides of the active cathode tool are both inclined structures that tilt inward from top to bottom, and one side surface of the active cathode tool is smoothly connected to the inner side wall of the left follower block, and the other side surface of the active cathode tool is smoothly connected to the inner side wall of the right follower block. When the active cathode tool moves downward, it can drive the left follower block and the right follower block to move horizontally outward synchronously.

[0013] Optionally, a machine tool spindle is connected to the top of the active cathode tool, and the machine tool spindle can drive the active cathode tool to move downward.

[0014] Optionally, the inner side walls of the left follower block and the right follower block are provided with guide rails arranged vertically along their inclined surfaces, and sliders are provided on both sides of the active cathode tool. The sliders are slidably arranged in the corresponding guide rails, and the sliders can slide up and down in the corresponding guide rails.

[0015] Optionally, it also includes a base, the workpiece is fixed on the base, and horizontally arranged guide rails are symmetrically provided at positions on both sides of the workpiece on the base. Sliders are provided at the bottom of the left follower block and the right follower block, and the sliders are slidably arranged in the guide rails on the same side.

[0016] Optionally, a support plate is provided on the outer side of the left follower block and the right follower block, and the support plate is fixed on the base; the outer side of the left follower block is connected to the support plate on its left side through a horizontally arranged spring, and the outer side of the right follower block is connected to the support plate on its right side through a horizontally arranged spring.

[0017] Optionally, the left follower block and the right follower block are both insulated from the base, and the left follower block and the right follower block are both insulated from the support plate; the cathode tool and the machining edge are coated with epoxy resin except for the microstructure machining part.

[0018] The present invention also provides a method for electrolytic machining of microstructures of a microchannel bottom and sidewalls, comprising the steps of:

[0019] Step 1: Install the workpiece to be processed on the base and connect the positive pole of the power supply to the workpiece;

[0020] Step 2: Connect the left and right driven cathode tools to the active cathode tool through the guide rail and the slider, and install them on the base. Install two support plates on the base, and connect the outer sides of the left and right driven cathode tools to the corresponding support plates through springs, and connect the negative pole of the power supply to the cathode tool;

[0021] Step 3: Check and calibrate the positions of the workpiece and the tool cathode;

[0022] Step 4: Align the cathode and the workpiece and confirm the initial relative position and machining gap;

[0023] Step 5: The electrolyte is introduced and the power is turned on. The active cathode tool begins to feed downward, while the left and right driven cathode tools simultaneously feed left and right. During this process, the spring is squeezed, causing electrochemical dissolution of the bottom and side walls of the microchannel. As the processing progresses, all microstructures are processed.

[0024] Step 6: After the processing is completed, the power is disconnected and the electrolyte supply is stopped. The active cathode tool returns to its original position. Due to the action of the springs on both sides, the left and right driven cathode tools are reset at the same time.

[0025] Compared with the prior art, the present invention has achieved the following technical effects:

[0026] The present invention utilizes a single array of cathode machining blades to machine all microstructures within an array of microchannels, eliminating cathode tool wear and fully leveraging the advantages of electrolytic machining, including high efficiency and low cost. The device's multi-directional, synchronized feed allows for simultaneous machining of the channel's bottom and sidewall microstructures, eliminating the need for multiple tooling disassembly and assembly, and improving machining repeatability. The present invention can also be used to manufacture internal structures such as blind cavities and plate heat exchangers, demonstrating strong process applicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0028] Figure 1 Schematic diagram of the microstructure electrolytic machining device for the bottom and sidewalls of the microchannel of the present invention;

[0029] Figure 2 Schematic diagram of the processing principle of the microstructure electrolytic processing device of the microchannel bottom and sidewall of the present invention;

[0030] Figure 3 A schematic diagram of a cathode tool of the microstructure electrochemical machining device for the bottom and sidewall of a microchannel according to the present invention;

[0031] Figure 4 Schematic diagram of the left driven cathode tool of the microstructure electrochemical machining device for the bottom and sidewall of a microchannel according to the present invention;

[0032] Figure 5 A schematic diagram of an active cathode tool of the microstructure electrochemical machining device for the bottom and sidewall of a microchannel according to the present invention;

[0033] Figure 6 Schematic diagram of the right driven cathode tool of the microstructure electrochemical machining device for the bottom and sidewall of a microchannel according to the present invention;

[0034] Figure 7 Schematic diagram of cathode tool assembly for the microstructure electrochemical machining device of the microchannel bottom and sidewall of the present invention.

[0035] In the figure: 1-active cathode tool, 101-active cathode machining edge, 2-left driven cathode tool, 201-left driven cathode machining edge, 3-right driven cathode tool, 301-right driven cathode machining edge, 4-workpiece, 5-slider, 6-spring, 7-support plate, 8-microstructure machining part, 9-base. DETAILED DESCRIPTION

[0036] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0037] The purpose of the present invention is to provide a device and method for electrolytic processing of microstructures on the bottom and side walls of a microchannel to solve the problems existing in the above-mentioned prior art. The device and method can simultaneously process the microstructures on the bottom and side surfaces of the microchannel, so that the microstructure processing efficiency in the microchannel is high and the heat exchange effect of the microchannel is good.

[0038] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0039] The present invention provides a microstructure electrolytic processing device for the bottom and side walls of a microchannel, such as Figures 1-7As shown, it includes a base 9, a cathode tool and a workpiece 4 to be processed, the workpiece 4 is set on the base 9, the workpiece 4 is connected to the positive pole of the external power supply, and a plurality of microchannels are opened on the workpiece 4, and electrolyte is passed into the microchannels; the cathode tool is connected to the negative pole of the external power supply, and the cathode tool has a processing edge with the same number as the microchannels, and the processing edge is provided with a protruding microstructure processing part 8; the processing edge extends into the corresponding microchannel, and the cathode tool in this embodiment includes an active cathode tool 1, a left driven cathode tool 2 and a right driven cathode tool 3; the processing edge includes an active cathode processing edge 101, a left driven cathode processing edge 201 and a right driven cathode processing edge 301; the active cathode tool 1 The top of the machine tool is connected to a machine tool spindle, which can drive the active cathode tool 1 downward. The bottom of the active cathode tool 1 is evenly distributed with multiple active cathode machining blades 101, each with a protruding microstructure machining portion 8. The bottom of the left driven cathode tool 2 is evenly distributed with multiple left driven cathode machining blades 201, with the left side of the left driven cathode machining blade 201 having a protruding microstructure machining portion 8. The bottom of the right driven cathode tool 3 is evenly distributed with multiple right driven cathode machining blades 301, with the right side of the right driven cathode machining blade 301 having a protruding microstructure machining portion 8. These are used to electrolytically machine the pit-shaped microstructures on the bottom and sidewalls of the microchannel. During machining, the positive pole of the power supply is connected to the workpiece 4 to be machined, and the negative pole of the power supply is connected to the three cathode tools. Electrolyte is introduced into the microchannel, and the machine tool spindle drives the middle active cathode tool 1 downward. Simultaneously, the two side driven cathode tools, driven by the active cathode tool 1, move left and right, respectively, so that the bottom and sidewalls of the microchannel are simultaneously machined into microstructures.

[0040] In order to enable the three cathode tools to work together without interfering with each other, the structure of the cathode tool is designed in this embodiment. The left driven cathode tool 2 is structurally designed to include a left driven block, the bottom of the left driven block is connected to a left bottom plate extending to the right, and the left bottom plate is provided with a first hole with the same number as the left driven cathode processing edge 201. The left driven cathode processing edge 201 is located at the bottom of the left bottom plate, and the right side surface of the left driven cathode processing edge 201 is located on the same plane as the left side wall of the corresponding first hole; the right driven cathode tool 3 is structurally designed to include a right driven block, the bottom of the right driven block is connected to a right bottom plate extending to the left, and the right bottom plate A second hole with the same number as the right driven cathode machining edge 301 is opened on it, and the right driven cathode machining edge 301 is located at the bottom of the right base plate, and the left side of the right driven cathode machining edge 301 is located on the same plane as the right side wall of the corresponding second hole; the active cathode machining edge 101 passes through the corresponding second hole and the first hole, and extends into the corresponding microchannel. After the right driven cathode machining edge 301 passes through the corresponding first hole, it extends into the corresponding microchannel. In each microchannel, a left cathode machining edge, an active cathode machining edge 101 and a right cathode machining edge are provided in sequence from left to right, and there is no interference between the three machining edges.

[0041] In order to achieve the goal of synchronously driving the two driven cathode tools to move to both sides when the active cathode tool 1 moves downward, the inner walls of the left driven block and the right driven block are designed in this embodiment as an inclined surface structure that gradually tilts inward from top to bottom. Both sides of the active cathode tool 1 are inclined surface structures that tilt inward from top to bottom. The inner walls of the left driven block and the right driven block are provided with guide rails arranged vertically along their inclined surfaces. Sliders 5 are provided on both sides of the active cathode tool 1. The slides 5 are slidably arranged in the corresponding guide rails, and the slides 5 can slide up and down in the corresponding guide rails. When the active cathode tool 1 moves downward, it can drive the left driven block and the right driven block to move synchronously outward horizontally.

[0042] In order to make the left follower block and the right follower block move more smoothly, this embodiment has symmetrically arranged horizontal guide rails on the base 9 at positions on both sides of the workpiece 4, and sliders 5 are provided at the bottom of the left follower block and the right follower block. The sliders 5 are slidably set in the guide rails on the same side, further making the left follower block and the right follower block slide more smoothly.

[0043] To ensure the cathode tool can be reset after machining is complete, a support plate 7 is installed on the outside of each left and right follower block, fixed to a base 9. The outside of the left follower block is connected to the support plate 7 on its left side via a horizontally arranged spring 6, and the outside of the right follower block is connected to the support plate 7 on its right side via a horizontally arranged spring 6. This allows the cathode tool to return to its original position when retracting the tool. The left and right follower blocks are insulated from the base 9 and the support plate 7. The cathode tool and the machining edge, except for the microstructure machining portion 8, are coated with epoxy resin.

[0044] The present invention also provides a method for electrolytic machining of microstructures of a microchannel bottom and sidewalls, comprising the steps of:

[0045] Step 1: Mount the workpiece 4 to be processed on the base 9 and connect the positive pole of the power supply to the workpiece 4;

[0046] Step 2: Connect the left driven cathode tool 2 and the right driven cathode tool 3 to the active cathode tool 1 through the guide rail and the slider 5, and install them on the base 9. Install two support plates 7 on the base 9, and connect the outer sides of the left driven cathode tool 2 and the right driven cathode tool 3 to the corresponding support plates 7 through the spring 6, and connect the negative pole of the power supply to the cathode tool;

[0047] Step 3: Check and calibrate the positions of the workpiece 4 and the tool cathode;

[0048] Step 4: Align the cathode and the workpiece 4 and confirm the initial relative position and machining gap;

[0049] Step 5: Electrolyte is introduced and power is turned on. The active cathode tool 1 begins to advance downward, while the left and right driven cathode tools 2 and 3 advance left and right. During this process, the spring 6 is squeezed, causing electrochemical dissolution of the bottom and side walls of the microchannel. As the processing progresses, all microstructures are processed.

[0050] Step 6: After the processing is completed, the power is disconnected and the electrolyte supply is stopped. The active cathode tool 1 returns to its original position. Due to the action of the springs 6 on both sides, the left driven cathode tool 2 and the right driven cathode tool 3 are reset at the same time.

[0051] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only intended to help understand the method and core concept of the present invention. At the same time, those skilled in the art will find that the specific implementation methods and application scopes may vary based on the concept of the present invention. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims

1. A microstructure electrochemical machining device for the bottom and sidewalls of a microchannel, characterized by: include: A workpiece, the workpiece is connected to a positive electrode of an external power supply, and the workpiece is provided with a plurality of microchannels, wherein the microchannels are filled with electrolyte; a cathode tool, the cathode tool being externally connected to a negative electrode of a power supply and having machining edges equal in number to the number of the microchannels, the machining edges being provided with outwardly protruding microstructure machining portions; the machining edges extending into the corresponding microchannels and being capable of simultaneously electrolytically machining the inner bottom and two inner sidewalls of the microchannels to form microstructures; The cathode tool comprises an active cathode tool, a left driven cathode tool and a right driven cathode tool; the machining blade comprises an active cathode machining blade, a left driven cathode machining blade and a right driven cathode machining blade; a plurality of active cathode machining blades are evenly arranged at the bottom of the active cathode tool, and the bottom of the active cathode machining blade is provided with the convex microstructure machining portion, a plurality of left driven cathode machining blades are evenly arranged at the bottom of the left driven cathode tool, and the left side of the left driven cathode machining blade is provided with the convex microstructure machining portion, a plurality of right driven cathode machining blades are evenly arranged at the bottom of the right driven cathode tool, and the right side of the right driven cathode machining blade is provided with the convex microstructure machining portion; the top of the active cathode tool is connected to a machine tool spindle, and the machine tool spindle can drive the active cathode tool to move downward, and at the same time, the two driven cathode tools on the side move left and right respectively under the drive of the active cathode tool, so that the bottom and side wall of the microchannel are processed with microstructures at the same time; the left driven cathode tool comprises a left driven block, and the bottom of the left driven block It is connected to a left bottom plate extending to the right, and a first hole is provided on the left bottom plate, the number of which is the same as that of the left driven cathode machining edge. The left driven cathode machining edge is located at the bottom of the left bottom plate, and the right side surface of the left driven cathode machining edge is in the same plane as the left side wall of the corresponding first hole; the right driven cathode tool includes a right driven block, the bottom of the right driven block is connected to a right bottom plate extending to the left, and a second hole is provided on the right bottom plate, the number of which is the same as that of the right driven cathode machining edge. The right driven cathode machining edge is located at the bottom of the right bottom plate, and the left side surface of the right driven cathode machining edge is in the same plane as the right side wall of the corresponding second hole; the active cathode machining edge extends into the corresponding microchannel after passing through the corresponding second hole and the first hole in sequence, and the right driven cathode machining edge extends into the corresponding microchannel after passing through the corresponding first hole. In each of the microchannels, a left cathode machining edge, an active cathode machining edge and a right cathode machining edge are provided in sequence from left to right, and the three machining edges do not interfere with each other.

2. The microstructure electrochemical machining device for the bottom and sidewalls of a microchannel according to claim 1, characterized in that: The inner side walls of the left follower block and the right follower block are both inclined structures that gradually tilt inward from top to bottom, and both sides of the active cathode tool are both inclined structures that tilt inward from top to bottom, and one side surface of the active cathode tool is smoothly connected to the inner side wall of the left follower block, and the other side surface of the active cathode tool is smoothly connected to the inner side wall of the right follower block. When the active cathode tool moves downward, it can drive the left follower block and the right follower block to move horizontally outward synchronously.

3. The microstructure electrochemical machining device for the bottom and sidewalls of a microchannel according to claim 2, characterized in that: The inner side walls of the left follower block and the right follower block are provided with guide rails arranged vertically along their inclined surfaces, and sliders are provided on both sides of the active cathode tool. The sliders are slidably arranged in the corresponding guide rails, and the sliders can slide up and down in the corresponding guide rails.

4. The microstructure electrochemical machining device for the bottom and sidewalls of a microchannel according to claim 2, characterized in that: It also includes a base, the workpiece is fixed on the base, and horizontally arranged guide rails are symmetrically provided at positions on both sides of the workpiece on the base. Slide blocks are provided at the bottom of the left follower block and the right follower block, and the slide blocks are slidably arranged in the guide rails on the same side.

5. The microstructure electrochemical machining device for the bottom and sidewalls of a microchannel according to claim 4, characterized in that: A support plate is provided on the outer side of the left follower block and the right follower block, and the support plate is fixed on the base; the outer side of the left follower block is connected to the support plate on its left side through a horizontally arranged spring, and the outer side of the right follower block is connected to the support plate on its right side through a horizontally arranged spring.

6. The microstructure electrochemical machining device for the bottom and sidewalls of a microchannel according to claim 4, characterized in that: The left follower block and the right follower block are both insulated from the base, and are also insulated from the support plate; the cathode tool and the machining edge are coated with epoxy resin except for the microstructure machining portion.

7. A method for electrochemical machining of microchannel bottom and sidewall microstructures based on the apparatus for electrochemical machining of microchannel bottom and sidewall microstructures according to any one of claims 1 to 6, characterized in that: Including steps: Step 1: Install the workpiece to be processed on the base and connect the positive pole of the power supply to the workpiece; Step 2: Connect the left and right driven cathode tools to the active cathode tool through the guide rail and the slider, and install them on the base. Install two support plates on the base, and connect the outer sides of the left and right driven cathode tools to the corresponding support plates through springs, and connect the negative pole of the power supply to the cathode tool; Step 3: Check and calibrate the positions of the workpiece and the tool cathode; Step 4: Align the cathode and the workpiece and confirm the initial relative position and machining gap; Step 5: Electrolyte is introduced, power is turned on, and the active cathode tool begins to advance downward. Simultaneously, the left and right driven cathode tools advance left and right, causing electrochemical dissolution of the bottom and side walls of the microchannel. As processing progresses, all microstructures are processed. Step 6: After the processing is completed, the power is disconnected and the electrolyte supply is stopped. The active cathode tool returns to its original position. Due to the action of the springs on both sides, the left and right driven cathode tools are reset at the same time.

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