Cross-scale internal cooling structured grinding wheel based on bionics

Abstract

The invention provides a cross-scale internal cooling structured grinding wheel based on bionics, which is basically characterized in that the cross-scale internal cooling structured grinding wheel comprises a grinding wheel main body, cover plates on two sides of the grinding wheel and three bionic structure grooves on the surface of the grinding wheel, and the three bionic structure grooves are all manufactured on the surface of the grinding wheel through a laser processing technology; wherein the two types of macroscopic bionic structure grooves refer to crotch structures and carp body surface scales, are distributed in the circumferential surface and the end surface, are communicated with each other and act together, and have the effects of inhibiting flow field disturbance, improving the cooling effect and reducing grinding burns; according to the microstructure groove, the microstructure groove similar to the surface structure of the pitcher plant mouth edge is machined in the macrostructure groove by simulating the function and the structural feature of unidirectional spreading of liquid on the surface of the pitcher plant mouth edge, and the capillary wedge effect generated by the wedge feature of the microstructure is utilized; and the grinding fluid performs single-direction spreading movement on the surface under the action of the capillary wedge-shaped effect, so that the unpowered conveying of the grinding fluid on the surface of the grinding wheel is realized. The three structures form a macroscopic-to-microcosmic multi-stage transmission network, the three bionic structure grooves have a cross-scale synergistic effect, the grinding temperature of the action area of the grinding wheel and a workpiece is reduced, and efficient and high-quality grinding machining is achieved.

Description

Technical Field

[0001] This invention relates to a grinding wheel, and more particularly to a biomimetic multi-scale internal cooling structured grinding wheel, belonging to the field of grinding wheel design, manufacturing and processing technology. Background Technology

[0002] In the field of machining, especially precision machining, grinding is a key precision machining method for achieving high surface quality and dimensional accuracy, playing an indispensable role in high-end manufacturing fields such as aerospace. However, when grinding wheels rotate at high speeds, numerous problems arise, severely affecting machining efficiency, wheel life, and workpiece quality. Currently, traditional grinding wheels have some significant limitations. During grinding, grinding debris easily clogs the wheel, leading to a sharp reduction in the number of effective abrasive grains and grinding edges, and rapid heat accumulation in the grinding zone. While ordinary grooved grinding wheels improve flow field issues to some extent, they often have evenly spaced straight grooves, resulting in uneven cooling medium delivery. This can easily lead to heat dissipation blind spots due to flow channel congestion or low flow velocity, ultimately causing workpiece burns and deterioration of surface quality. Furthermore, the high-speed rotation of the grinding wheel creates a strong airflow barrier, resulting in an effective cooling medium delivery rate of less than 30%, wasting resources and polluting the environment. Secondly, with internally cooled grinding wheels, coolant cannot be accurately delivered to the grinding area, resulting in significant coolant waste. For example, the biomimetic structured grinding wheel disclosed in Chinese Patent (Publication No.: CN110842801A) and the biomimetic grinding wheel based on the scales and leaf arrangement of grass carp disclosed in Chinese Patent (Publication No.: CN114193342A), while having some effect on enhancing cooling, still do not fully solve the problem of self-transportation of the cooling medium by the grinding wheel matrix, resulting in the overall grinding wheel's ability to transport grinding fluid failing to meet practical needs. To overcome these shortcomings of the prior art, this invention proposes a biomimetic multi-scale internal cooling structured grinding wheel. This design aims to construct a unique multi-scale internal cooling structure by mimicking the efficient material transport and heat dissipation mechanisms within living organisms, thereby improving the grinding wheel's efficiency in transporting and utilizing grinding fluid, enhancing cooling, lubrication, and chip removal performance, effectively reducing grinding temperature, and improving grinding wheel life and workpiece machining quality. Summary of the Invention

[0003] The purpose of this invention is to provide a cross-scale internal cooling structured grinding wheel.

[0004] The technical solution proposed by this invention is as follows:

[0005] This invention proposes a biomimetic multi-scale internal cooling structured grinding wheel, which includes a grinding wheel body, a right grinding wheel cover plate, a left grinding wheel cover plate, and biomimetic structural grooves. The biomimetic structural grooves include three types: macroscopic tree branch structure grooves, mesoscopic fish scale structure grooves, and microscopic pitcher plant structure grooves. The macroscopic tree branch structure grooves, mesoscopic fish scale structure grooves, and microscopic pitcher plant structure grooves are all manufactured on the surface of the grinding wheel by laser processing.

[0006] The present invention provides a central hole penetrating the grinding wheel in the central region of the grinding wheel end face. An annular groove is machined into the wall of the central hole, extending circumferentially along the central hole, and the depth of the groove is limited to 5mm~10mm. When grinding fluid is sprayed onto the end face of the grinding wheel at a preset pressure, the groove wall and the cover plates mounted on both sides of the grinding wheel end face form a sealed fit, together enclosing a closed receiving space. This receiving space can temporarily store the grinding fluid sprayed onto the grinding wheel end face, preventing the grinding fluid from flowing away along the grinding wheel end face without participating in the grinding process, thereby effectively reducing the consumption of grinding fluid and minimizing resource waste.

[0007] The tree-branch-like groove structure on the side of the grinding wheel in this invention draws inspiration from the distribution of tree branches. This branch-like structure helps optimize the fluid flow path, reducing eddies and fluid resistance. This effectively improves efficiency and reduces energy loss in the delivery of grinding fluid. The branch-like distribution effectively guides the fluid to flow along multiple branches, avoiding the excessive local velocity or uneven flow that can occur in a single channel. The tree-branch-like groove structure helps improve the uniformity of the fluid in the system, allowing the fluid to be distributed over a wider area, avoiding excessive concentration or blockage. The tree-branch-like groove structure achieves more uniform fluid flow and enhances heat exchange. This results in lower grinding temperature, improved lubrication and cooling performance of the grinding wheel, and improved workpiece machining quality.

[0008] The design concept of the biomimetic groove on the end face of the grinding wheel in this invention is inspired by carp scales. These grooves are manufactured on the surface of the grinding wheel using laser processing technology. The design is inspired by the arrangement of carp scales, drawing on their properties in suppressing flow disturbances, improving the average convective heat transfer coefficient, and enhancing anti-adhesion capabilities. Each biomimetic groove on the grinding wheel surface is spiral-shaped along the axial direction. Carp can swim nimbly in water and are difficult for predators to detect; mud and bacteria also have difficulty adhering to their surface. All of this is closely related to the arrangement and shape of their scales. The scales overlap each other, and the parts in contact with water are rhomboid in shape. This special arrangement and angle give carp scales unique functions such as suppressing flow disturbances, improving the convective heat transfer coefficient, and resisting adhesion. Therefore, the biomimetic groove on the grinding wheel can improve the utilization rate of grinding fluid, enhance heat dissipation, and reduce grinding debris clogging during grinding.

[0009] The design concept of the biomimetic microstructure groove on the end face of the grinding wheel in this invention is inspired by the structure of the pitcher plant's mouth. The mouth utilizes the surface curvature, concave surface, and arched channel on the conical teeth (ratchet) to continuously and rapidly collect and transport condensate. Even with the tooth tips pointing downwards, the ratchet teeth and concave surface enhance Laplace pressure, resulting in anti-gravity transport of condensate. The synergistic curvature between adjacent teeth prevents condensate from dripping and successfully propels the collected water upwards at extremely high speeds—this is the positive spreading motion of the liquid on the surface of the pitcher plant's mouth edge. Through the combined action of the ratchet, serrated teeth, and arched structure, record-breaking water collection and transport speeds are achieved. This results in high grinding fluid utilization, good heat dissipation, and minimal grinding debris clogging during grinding.

[0010] Advantages and Effects: A biomimetic multi-scale internal cooling structured grinding wheel was designed. Through the interplay of end-face grooves mimicking tree branches and circumferential grooves mimicking fish scales, along with microscopic grooves mimicking the single-channel flow path of a pitcher plant, a multi-scale grinding wheel was achieved, moving from the microscopic to the mesoscopic to the macroscopic, introducing biomimetic principles into grinding wheel design. A biomimetic surface structure groove for unidirectional liquid spreading was designed. From a biomimetic perspective, it imitates the function and characteristics of unidirectional liquid spreading at the edge of a pitcher plant, machining a wedge-shaped structure on the surface. Utilizing the unique capillary wedge effect of the wedge structure, unidirectional liquid spreading is effectively achieved, enabling unidirectional spreading and transport of grinding fluid on the grinding wheel surface. The macroscopic structure groove enhances cooling, lubrication, and chip removal during grinding, improving workpiece machining accuracy, extending tool life, reducing grinding fluid consumption, and increasing grinding efficiency. The three structures form a multi-level transmission network from macro to micro. The three biomimetic groove structures work synergistically across scales to reduce the grinding temperature in the interaction area between the grinding wheel and the workpiece, thereby achieving efficient and high-quality grinding. Attached Figure Description

[0011] Figure 1 This is a three-dimensional view of the combined biomimetic structured grinding wheel of the present invention.

[0012] Figure 2 This is a schematic diagram showing the surface development of the combined biomimetic structured grinding wheel of the present invention.

[0013] Figure 3 This is a schematic diagram of the internal cooling pipe and the single-channel structure of the pitcher plant. Detailed Implementation

[0014] The present invention will now be described more clearly and completely with reference to the accompanying drawings in the embodiments of the present invention.

[0015] like Figure 1The schematic diagram of the biomimetic structured grinding wheel shown includes the grinding wheel body (1), abrasive section (2), grinding wheel left cover plate (3), grinding wheel left cover plate (4) and biomimetic structure groove (5); the biomimetic structure groove (5) includes macroscopic tree branch structure groove (6), mesoscopic fish scale structure groove (7) and microscopic pitcher plant structure groove (8).

[0016] Figure 2 This is a schematic diagram showing the unfolded surface of the combined biomimetic structured grinding wheel of the present invention. The biomimetic structural grooves are 1 mm wide and 1-2 mm deep. The biomimetic structural grooves are interlaced, forming a rhombus shape around the surface of the grinding wheel. The rhombuses are arranged with a vertices of 137.5° (golden angle) in the direction of rotation of the grinding wheel, and an included angle of 42.5° in the axial direction of the grinding wheel.

[0017] Figure 3 The invention utilizes a microstructure mimicking the unidirectional liquid spreading surface of a pitcher plant within the internal cooling pipe, distributed within a tree-branch-like groove on the end face of the grinding wheel. Figure 3 A structure matching the three-dimensional features of the oblique aperture structure on the surface of the pitcher plant was demonstrated, incorporating an arc-shaped ridge with a height of 8 μm. The outer contour of a single oblique aperture is semi-elliptical, with a major axis of 80 μm and a minor axis of 20 μm. The plane containing the outer contour forms an angle of approximately 10° with the plane perpendicular to the ridge direction. The inner contour of a single oblique aperture structure is also semi-elliptical, with a major axis of 125 μm and a minor axis of 25 μm. The plane containing the inner contour forms an angle of 10° with the plane perpendicular to the ridge direction. This demonstrates that the wedge-shaped angle formed by the inner contour generates a wedge effect, which in turn induces a capillary wedge effect in the liquid, causing the liquid to expand and flow along the interior of the oblique aperture.

[0018] The slanted pit structure, simplified from the pitcher plant's rim structure, can form linear or planar textures that can be processed using laser engraving technology. These textures exhibit distinct directional wedge-shaped features, allowing liquids on the surface to spread and flow in a direction toward the interior of the triangular pits.

[0019] First, an abrasive layer for the grinding wheel is manufactured using a sintering process. Then, the biomimetic structural groove is machined on the surface of the abrasive layer using a laser process. The laser beam is aligned with the diameter direction of the grinding wheel to ensure the uniformity and stability of the biomimetic structural groove shape. The laser beam moves repeatedly along the axial direction of the grinding wheel, while the grinding wheel rotates axially, completing the machining of the biomimetic structural groove on the surface of the grinding wheel. A microstructure resembling a pitcher plant is then laser-engraved within the structural groove of the grinding wheel.

Claims

1. A biomimicry based cross scale internal cooling structured grinding wheel characterized in that: The grinding wheel comprises a grinding wheel body (1), an abrasive section (2), a grinding wheel left cover plate (3), a grinding wheel left cover plate (4) and a bionic structure groove (5); the bionic structure groove (5) comprises macroscopic imitation of tree branch structure groove (6), mesoscopic imitation of fish scale structure groove (7), microscopic imitation of Nepenthes structure groove (8); the grinding wheel side surface has the imitation of tree branch structure groove (6), the imitation of tree branch structure groove (6) comprises multiple third branches, the first branch extends radially outward to one third of the grinding wheel edge with the grinding wheel center as the shaft, and constitutes the main stem of the entire branch system; the second branch extends two branches from the end of each first branch (i.e. one third of the grinding wheel edge) to the grinding wheel edge, and finally reaches two thirds of the grinding wheel edge, forming the first expansion of the first branch; the third branch extends two branches from the end of each second branch (i.e. two thirds of the grinding wheel edge) to the grinding wheel edge again, until it touches the grinding wheel end surface, completing the final coverage of the branch system from the center to the edge; the grinding wheel body end surface comprises mesoscopic imitation of fish scale structure groove (7), the bionic structure groove cross section is circular arc shape, which is composed of multiple interlaced rhombic scale structures, the rhombuses are interlaced, the scale width and height are consistent, and they form a close but unblocked arrangement; the macroscopic imitation of tree branch structure groove (6) and the mesoscopic imitation of fish scale structure groove (7) are connected at the intersection of the grinding wheel end surface and side surface, the groove width at the connection is equal, and the two grooves jointly provide a flow channel for the grinding fluid, so that more grinding fluid can enter the grinding area, reducing the grinding temperature and reducing the grinding burn; the grinding wheel side surface has the imitation of Nepenthes structure groove (8), the microscopic imitation of Nepenthes structure groove (8) is in the macroscopic imitation of tree branch structure groove (6) on the surface of the grinding wheel, the structure surface is distributed with dense micron-level pits or protrusions, similar to the outline of a reduced "cage", the pit is mostly irregular circular or elliptical, the pit diameter is slightly larger than the pit bottom, forming a "wide outside and narrow inside" funnel structure, and small ridge-shaped protrusions are distributed between the pits, simulating the "toothed structure" of the Nepenthes trap edge; the three structures form a multi-level transmission network from macro to micro, and the three bionic structure grooves synergistically reduce the grinding temperature of the grinding wheel and workpiece interaction area, realizing efficient and high-quality grinding processing.

2. The tree branch structure slot (6) according to claim 1, characterized in that: The bifurcation angle of the bifurcation structure is 55°-65°, so as to optimize the cooling effect in the grinding process. The pore diameter of the first level of pores is 4-6 mm, the pore diameter of the second level of pores is smaller than that of the first level of pores, the pore diameter of the third level of pores is smaller than that of the second level of pores, the pore diameter of the second level of pores is 2-4 mm, and the pore diameter of the third level of pores is 1-2 mm.

3. The fish scale structure groove (7) according to claim 1 has the size of 3-5 mm in depth and 1-2 mm in width. The bionic structure groove 4 imitates the arrangement characteristics of the scales 6 on the body surface of a carp, and the rhombic arrangement has a top angle of 130-140° in the rotation direction of the grinding wheel, wherein the most common golden angle of 137.5° is optimal. It has the advantages of inhibiting flow field disturbance, improving the average convective heat transfer coefficient, and resisting adhesion. Its special arrangement can effectively improve the fluid dynamics performance, enhance the heat exchange efficiency, and reduce the deposition of adhesion.

4. The microgroove (8) of the structure of the Nepenthes pig imitation according to claim 1, characterized by: The surface structure groove in the end face structure groove is consistent with or similar to the surface structure of the mouth edge of the Nepenthes, which means that the unit structure of the surface groove has a similar inclined hole, inclined pit, and inclined groove structure that can produce a capillary wedge effect. This structure is distributed in the macro-groove, and the two can cooperate with each other to quickly transport the grinding fluid, unpowered transport the grinding fluid, and improve the cooling effect. The width of a single structure groove is 50-55 μm, and the height of the groove ridge is 8-9 μm. The single inclined hole has a semi-elliptical shape, with a long semi-axis of 80-82 μm and a short semi-axis of 20-22 μm. The plane on which the outer contour is located forms an angle of about 10° with the plane perpendicular to the direction of the groove ridge. The inner contour of the single inclined hole structure is also semi-elliptical, with a long semi-axis of 123-125 μm and a short semi-axis of 25-27 μm. The angle between the plane on which the inner contour is located and the plane perpendicular to the direction of the groove ridge is 10°.

5. The center hole recess of a grinding wheel of claim 1 wherein: The groove is processed on the hole wall of the center hole, the groove extends along the circumference of the center hole, and the depth of the groove is limited to 5-10 mm. When the grinding fluid is sprayed to the end face of the grinding wheel at a predetermined pressure, the groove wall forms a sealing fit with the cover plate assembled on both sides of the end face of the grinding wheel, and together encloses a closed accommodation space.

Images