A circular ring workpiece edge grinding machine

Abstract

This invention relates to a ring-shaped workpiece edge grinding machine, belonging to the field of grinding manufacturing technology. It includes a bottom transmission mechanism, an upper feed and transmission mechanism, a telescopic tolerance and fluid flow structure, and a fluid dynamic pressure suspension structure. The upper structure adopts a two-section tube body. The hollow tube and the rotating tube are fixedly connected by multiple sets of telescopic rods, and the fluid flow is achieved by an internal hose. The bottom surface of the planetary plate is machined with equal-width sloping dynamic pressure fluid grooves at intervals along the circumference, and the depth of the groove bottom becomes shallower along the flow direction. The external fluid is injected into the bottom surface of the planetary plate through the hollow tube, hose and the inside of the sun gear spindle from the radial diversion hole. Under the squeezing action of relative rotation, the fluid is compressed in volume in the dynamic pressure fluid groove, generating an upward thrust, which lifts the planetary plate to achieve suspension. This solution solves the mechanical impact problem during mold closing and reduces the friction of the bottom surface by utilizing the dynamic pressure effect.

Description

Technical Field

[0001] This invention belongs to the field of grinding manufacturing technology, specifically, it relates to a grinding machine for circular workpieces. Background Technology

[0002] In the field of mechanical grinding and manufacturing of ring-shaped workpieces, planetary double-sided grinding machines are a common type of processing equipment. The physical frame of this equipment typically includes a lower grinding disc, a central sun gear, an outer internal gear ring, and a planetary plate sandwiched between the teeth of the central sun gear and the outer internal gear ring. During operation, the ring-shaped workpiece is loaded into the cavity of the planetary plate, with a downward clamping force applied from the top by the upper grinding disc. The central sun gear and the outer internal gear ring move the planetary plate through their tooth surfaces, forcing it to undergo sliding friction on the top surface of the lower grinding disc through a combination of revolution and rotation, thereby achieving physical cutting of the workpiece's end face.

[0003] Regarding the aforementioned mechanical structure, a core technical problem currently facing the industry is that, under heavy-load and compaction conditions, severe dry metal friction and physical wear inevitably occur between the bottom surface of the planetary plate and the bottom support step.

[0004] Specifically, during the mold-closing stage, the top spindle box must drive the upper grinding disc downwards to effectively apply and press the machining load onto the annular workpiece. However, traditional machine tool feed spindles typically employ a single-segment rigid shaft tube structure with vertically connected sections. When the upper grinding disc applies downward pressure, due to the lack of a physical absorption and isolation structure for axial displacement, this vertically downward thrust is rigidly transmitted downwards along the mechanical components, causing the planetary plate to be rigidly pressed against the first and second limiting steps at the bottom.

[0005] Under such immense downward pressure, an extremely tight metallic contact is formed between the bottom surface of the planetary plate and the supporting step. When the motor-driven gear rotates and the planetary plate begins to slide, the supporting step on the bottom surface must withstand the downward gravity of the planetary plate and the workpiece, as well as the additional pressure from the top. This direct physical sliding under heavy pressure completely destroys the basic sliding conditions of the metal surface, leaving the contact surface in a state of pure dry friction. As the disc continues to rotate, the mechanical dry friction generates a large amount of frictional heat, causing physical peeling, scratches, and even localized seizing of the metal surfaces of the planetary plate bottom surface and the supporting step, greatly shortening the physical service life of the supporting components; it also easily leads to overload and jamming of the peripheral drive gear and motor due to excessive frictional resistance on the bottom surface.

[0006] To alleviate this dry friction problem on the bottom surface, conventional physical methods typically involve spraying coolant from outside the machine tool onto the grinding area. However, under actual mechanical operating conditions, the bottom surface of the planetary gear and the supporting step are tightly pressed together by the downward load, completely closing any edge gaps. Coolant sprayed from the outside using gravity or low pressure cannot be forcibly injected into the tightly fitted bearing area when it encounters the physical resistance of centrifugal force generated by high-speed rotation. This results in water on the surface of the upper components, while the bottom, actual stress-bearing surface remains in a state of dry friction due to lack of water.

[0007] Therefore, from the perspective of mechanical hardware design, how to physically cut off the rigid pressure of the top downward displacement on the bottom without losing the transmission of rotational torque, and construct an independent flow channel that can force the fluid to be injected into the bottom closed bearing surface and lift the planetary plate by the fluid's physical thrust, has become a single and core engineering technical problem that urgently needs to be solved in the mechanical architecture iteration of this type of edge grinding machine. Summary of the Invention

[0008] The purpose of this invention is to provide a ring-shaped workpiece edge grinding machine, which solves the problem in the prior art where the traditional edge grinding machine lacks axial force isolation, resulting in severe metal dry friction of the planetary blades under the heavy pressure of mold closing, and the external coolant is unable to enter the bottom bearing gap due to compression and centrifugal force, causing the bottom surface fluid lubrication and mechanical chip removal to completely fail.

[0009] The objective of this invention can be achieved through the following technical solutions: A ring-shaped workpiece edge grinding machine mainly includes an upper grinding disc, a lower grinding disc, a central sun gear, a peripheral internal gear ring, and a planetary plate placed between the central sun gear and the peripheral internal gear ring. The planetary plate has a cavity on its surface for accommodating the ring-shaped workpiece, comprising: The bottom transmission mechanism includes a lower grinding disc spindle and a sun gear spindle that passes through the interior of the lower grinding disc spindle; a lower grinding disc drive motor drives the lower grinding disc spindle and the lower grinding disc to rotate, and a sun gear drive motor drives the sun gear spindle and the central sun gear to rotate; an internal gear ring drive motor drives the outer internal gear ring to rotate. The upper feed and transmission mechanism includes a spindle box that moves up and down along a vertical track, a hollow tube installed in the spindle box, and a rotating tube located below the hollow tube; the bottom of the rotating tube is rotatably connected to a positioning blind hole bearing seat located at the top of the sun gear spindle via a bearing; the upper grinding disc drive motor drives the hollow tube and the upper grinding disc to rotate; The telescopic tolerance and fluid passage structure includes multiple sets of telescopic rods fixedly connected between the bottom end face of the hollow tube and the top end face of the rotating tube; a flexible hose is fixedly connected between the internal cavities of the hollow tube and the rotating tube; external high-pressure fluid enters the rotating tube through the hollow tube and the flexible hose, and passes through the positioning blind hole bearing seat to enter the interior of the sun gear spindle. The hydrodynamic suspension structure has several hydrodynamic fluid grooves spaced circumferentially on the bottom surface of the planetary plate; the sun gear spindle has a radial diversion hole, which injects high-pressure fluid into the bottom surface of the planetary plate. Under the shear force of the relative rotation of the grinding disk and the planetary plate, the fluid enters the hydrodynamic fluid groove and is axially compressed, generating an upward hydrodynamic support force. The scheme achieves differential drive through three motors at the bottom: the first motor drives the lower grinding disc, the second motor drives the central sun gear through the main shaft inside the sleeve, and the third motor drives the outer internal gear ring, with the planetary plate sandwiched in between, performing planetary motion under the speed difference.

[0010] The core implementation lies in the upper "two-section" structure: the hollow tube and the rotating tube are not directly rigidly connected, but are connected by multiple sets of telescopic rods distributed circumferentially. When the spindle box moves down, the telescopic rods slide and retract, absorbing redundant stroke; while during rotation, the telescopic rods act as the force-bearing entities to transmit torque, and the flexible hose inside the tube is responsible for bridging this displacement change, introducing high-pressure water into the sun gear.

[0011] Furthermore, a lifting spindle is provided on the top of the machine tool, and the lifting spindle is connected to the spindle box to drive its lifting; the external water inlet pipe is connected to the top of the hollow tube through a rotary joint set in the spindle box; A vertically arranged lifting spindle is installed on the top of the machine tool, which moves the spindle box up and down via a lead screw or hydraulic cylinder. To allow water to be injected while rotating, a mechanical rotary joint is installed at the top of the hollow tube. An external water inlet pipe is fixed to one end of the joint, and the hollow tube rotates at the other end, ensuring that the fluid flows through without leakage during high-speed rotation.

[0012] Furthermore, the hollow tube has water outlet holes on its sidewalls, which face the area between the upper grinding disc and the top surface of the planetary plate. These water outlet holes are drilled radially directly into the hollow tube near the upper grinding disc. When the high-pressure fluid flows downwards, centrifugal force causes a portion of the fluid to be ejected from these holes, directly covering the top surface of the planetary plate, thus achieving cooling and cleaning of the upper contact surface during grinding operations.

[0013] Furthermore, the hydrodynamic fluid channel, in its planar projection, is a long, narrow strip with the same width at both the upstream and downstream ends. In the depth direction, the hydrodynamic fluid channel is deepest at the upstream end and gradually shallows towards the downstream end, eventually becoming flush with the bottom surface of the planetary plate at the downstream end. The hydrodynamic fluid channel on the bottom surface of the planetary plate is machined using a straight-line milling process. To generate thrust, the bottom of the channel is milled into a slope: the deepest point is at the beginning, gradually decreasing in depth towards the other end, finally becoming completely flush with the bottom surface. This slope structure with equal width and gradually varying depth can generate a strong physical compression effect when fluid flows in.

[0014] Furthermore, a flush solid bearing surface is maintained between two adjacent hydrodynamic fluid channels; during the machining of the hydrodynamic fluid channels, unmilled solid material is retained between the channels. These retained flush solid surfaces are in close contact with the lower grinding disc during operation, acting as lateral water-retaining boundaries of the fluid channels to prevent fluid from overflowing laterally to both sides, thereby concentrating energy in the upward pushing direction.

[0015] Furthermore, the planetary plate is provided with a guide hole penetrating the top and bottom surfaces, and the bottom opening of the guide hole is located inside the water-facing end of the dynamic pressure fluid channel; the guide hole, penetrating the entire thickness, is directly machined into the planetary plate, and its position is precisely located at the deepest end of the dynamic pressure fluid channel. When the fluid flows between the grinding discs, this hole uses pressure difference and rotational shear force to guide the water flow from above the planetary plate and inject it into the starting point of the slope below.

[0016] Furthermore, the bottom surface of the planetary plate is provided with an unloading microgroove. One end of the unloading microgroove is connected to the tail end, and the other end extends to the edge of the planetary plate. The flow cross-sectional area of ​​the unloading microgroove is smaller than the flow cross-sectional area at the deepest point of the dynamic pressure fluid channel. At the shallowest end of the slope, a slender unloading microgroove is machined and connected to the edge. By controlling the cross-sectional area of ​​the unloading microgroove to be significantly smaller than the cross-sectional area of ​​the main channel, a physical throttling effect is produced. This "throttling and pressure-maintaining" design can maintain the fluid pressure in the channel while forcibly discharging the fluid carrying grinding debris from the edge.

[0017] Furthermore, a first upward-protruding limiting step is provided at the outer edge of the base of the central sun gear, and a second upward-protruding limiting step is provided at the inner edge of the base of the outer internal gear ring; there is a preset height difference between the top surfaces of the first and second limiting steps and the top surface of the lower grinding disc; a raised step is machined on both the sun gear base and the internal gear ring base. When the equipment is stopped or not supplied with water, the planetary plate is stably supported by these two steps. The step surface is slightly lower than the lower grinding disc surface, forming a fixed height difference space, which reserves a position for the initial static pressure pad layer of the fluid.

[0018] Furthermore, the overall thickness of the planetary plate is less than the thickness of the annular workpiece, and the thickness of the planetary plate's disk body is reduced during the design process to make it thinner than the workpiece. In the assembled state, when the upper grinding disk presses down, it will first contact the end face of the workpiece. This dimensional chain relationship ensures that the vertically downward clamping force acts on the part rather than on the planetary plate. Furthermore, the bottom of the peripheral internal gear ring is provided with an annular base, and the bottom of the machine tool is correspondingly provided with an annular support step. An annular wear-resistant belt is sandwiched between the annular base and the annular support step. The output end of the internal gear ring drive motor is provided with an internal gear ring drive gear, which meshes with the outer edge of the annular base. The bottom of the internal gear ring is provided with an annular base, below which is the support step of the machine tool base. A high-polymer wear-resistant belt is installed between the two to support the weight of the internal gear ring and absorb friction. The motor drives the entire internal gear ring with high torque by moving the tooth profile of the outer edge of the annular base through a small gear that meshes from the side.

[0019] The beneficial effects of this invention are: 1. This invention arranges multiple sets of telescopic rods and internal hoses in layers between the hollow tube and the rotating tube. When the mold is closed and pressed down, the sliding contraction of the telescopic rods absorbs the redundant axial downward displacement, cutting off the downward rigid impact force, and acts as the force-bearing entity for transmitting torque during rotation. At the same time, in conjunction with the radial flow holes of the sun gear spindle, water is forced into the bottom surface of the planetary plate. The mechanical shearing force of the relative rotation of the plates scrapes the fluid into the dynamic pressure fluid groove and generates an upward fluid support force, lifting the planetary plate entity and completely eliminating metal dry friction under heavy load.

[0020] 2. This invention involves machining a hydrodynamic fluid channel with an equal width and a shallow slope at the tail end on the bottom surface of the planetary plate, and retaining a flush solid bearing surface between adjacent channels as a physical water-blocking boundary. After the coolant is directly injected into the water-facing end through the guide hole, it is forced to surge towards the narrow tail end under the pushing force of relative sliding. Under the combined physical obstruction of the slope at the bottom of the channel and the solid bearing surfaces on both sides, it undergoes strong volume compression, thereby instantly generating a fluid thrust sufficient to overcome the pressure of the grinding edge above.

[0021] 3. This invention connects an unloading microchannel with a sudden reduction in flow cross-sectional area at the tail end of the dynamic pressure fluid channel. This microchannel physically constitutes a water-blocking throttling orifice, which can accumulate and maintain positive fluid pressure inside the dynamic pressure fluid channel; at the same time, the coolant continuously discharged outwards washes away the metal and grinding wheel debris generated by the friction of the planetary blade bottom surface, preventing hard debris particles from accumulating at the bottom and achieving mechanical self-cleaning of the working surface.

[0022] 4. In this invention, an upwardly protruding limiting step is machined on the base edge of the central sun gear and the outer internal gear ring. When the equipment stops due to water shortage, this step provides stable physical support for the planetary plate to fall. In the early stage of equipment startup, before the dynamic pressure thrust is generated, the reserved height difference space between the step surface and the lower grinding disc surface allows coolant to flow in in advance, forcibly squeezing in a layer of static pressure water pad with physical thickness, avoiding metal surface scratches and seizing during the instant of heavy-load motor startup. Attached Figure Description

[0023] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a cross-sectional view of the overall structure of the circular workpiece edge grinding machine of the present invention; Figure 2 for Figure 1 A magnified view of a section at point A in the middle; Figure 3 for Figure 2 A magnified view of a portion of region B in the middle; Figure 4 for Figure 2 A magnified view of a portion of region C in the middle; Figure 5 This is a top-section schematic diagram of the sandwich working area of ​​the edge grinding machine; Figure 6 This is a schematic diagram of a rotary joint and a fluid-through structure. Figure 7 A schematic diagram of the cross-section of the planetary plate and the workpiece assembly, and the hydrodynamic fluid tank; Figure 8 A bottom view of the hydrodynamic fluid channels and flow paths on the bottom surface of the planetary plate.

[0025] Figure label: 10-External water inlet pipe, 11-Rotary joint, 20-Lifting spindle, 21-Spindle box, 30-Upper grinding disc drive motor, 31-Upper grinding disc transmission gear set, 40-Hollow tube, 41-Water outlet, 42-Rotating pipe; 43-Hose; 44-Telescopic rod; 50-Upper grinding disc, 60-Annular workpiece, 70-Planetary planet, 71-Dynamic pressure fluid tank, 72-Water-facing end, 73-Tail end, 74-Unloading micro-groove, 75-Guide hole, 80-Central sun gear, 81-Positioning blind hole bearing seat 82-First limiting step, 90-Outer internal gear ring, 91-Annular base, 92-Annular support step, 93-Second limiting step, 100-Lower grinding disc, 110-Lower grinding disc spindle, 120-Sun gear spindle, 121-Radial flow divider hole, 130-Lower grinding disc drive motor, 131-Lower grinding disc transmission component, 140-Sun gear drive motor, 150-Internal gear ring drive motor, 151-Internal gear ring drive gear, 160-Annular wear-resistant belt, 170-Lower grinding disc spindle bearing seat. Detailed Implementation

[0026] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0027] The attached diagram is explained as follows: Figure 1-8 As shown; Figure 1 The overall mechanical structure and multi-axis transmission cross-section of the circular workpiece grinding machine described in this invention are shown. At the top of the machine tool, the lifting spindle 20 achieves downward mold closing by vertically pushing the spindle box 21. The rotary joint 11 at the top of the spindle box 21 introduces high-pressure fluid from the external water inlet pipe 10 into the hollow pipe. The hollow pipe and the rotating pipe below are connected by multiple sets of telescopic rods to form a sliding transmission frame, which absorbs excess downward stroke, cuts off rigid impact on the bottom bearing, and rigidly transmits the rotational torque at the top. At the bottom of the machine tool, the sun gear drive motor 140 drives the sun gear spindle coaxially through the outer sleeve, causing the central sun gear to rotate independently. On the side, the internal gear ring drive motor 150 meshes with the annular base tooth profile at the bottom of the outer internal gear ring via the internal gear ring drive gear 151 arranged on the side, driving the outer internal gear ring to rotate. Driven by the speed difference of the multi-axis motors, the planetary slide plates clamped in the tooth gaps carry the annular workpiece in differential planetary sliding motion.

[0028] Figure 2 Showing Figure 1The magnified view at point A clearly reveals the physical details of the force-bearing entity, multi-axis nested fit, and fluid flow in the core grinding area of ​​the machine tool; At the upper feed transmission end, the upper grinding disc drive motor 30 transmits the rotational torque to the hollow tube 40 through the upper grinding disc transmission gear set 31, which drives the top upper grinding disc 50 to press down on the end face of the annular workpiece 60. In the core interlayer working area, the annular workpiece 60 is embedded in the cavity of the planetary gear 70. The planetary gear 70 is engaged between the central sun gear 80 and the outer internal gear ring 90, and under the forced movement of the tooth surfaces on both sides, it drives the workpiece to slide planetarily on the top surface of the lower grinding disc 100. The annular base 91 at the bottom of the outer internal gear ring 90 is directly mounted on the annular support step 92 of the machine tool base, and an annular wear-resistant belt 160 is sandwiched between the two to withstand the physical sliding friction under heavy loads. At the bottom double-shaft nesting and water injection end, the lower grinding disc drive motor 130 drives the outer lower grinding disc main shaft 110 to rotate within the lower grinding disc main shaft bearing seat 170 via the lower grinding disc transmission component 131, thereby driving the lower grinding disc 100 to rotate. The inner sun gear main shaft 120 coaxially passes through the channel of the lower grinding disc main shaft 110.

[0029] Figure 3 Showing Figure 2 The enlarged view of area B in the middle section highlights the physical assembly and physical dimension chain relationship of each core load-bearing component in the vertical direction within the machine tool mezzanine working area. A direct comparison of the cross-sectional thicknesses reveals that the overall physical thickness of the planetary plate 70 is significantly less than the thickness of the annular workpiece 60 contained within it. In the assembled state, the bottom of the annular workpiece 60 is solidly attached to the top surface of the lower grinding disc 100. This dimensional distribution ensures that when the upper grinding disc presses downwards, the vertically downward thrust can pass over the planetary plate 70 and reliably press against the workpiece end face as a pure machining load. During machine tool shutdown or start-up phases due to water cut-off, the planetary blade 70 falls under its own weight, its bottom surface directly resting on the inner first limiting step 82 and the outer inner gear ring 90's second limiting step 93, thus gaining upward physical support. The figure clearly shows a fixed physical height difference between the top surfaces of the first limiting step 82 and the second limiting step 93 and the working surface of the lower grinding disc 100. This physical gap is precisely to accommodate the externally pumped high-pressure coolant and force a layer of hydrostatic water cushion before the motor-driven planetary blade 70 undergoes mechanical relative sliding, thus structurally preventing direct metal-to-metal dry friction between the planetary blade 70 and the lower grinding disc 100. In addition, the bottom support structure of the peripheral transmission component is also clearly shown on the right side of the figure: the annular base 91 at the bottom of the peripheral internal gear ring 90 is directly mounted on the annular support step 92 at the bottom of the machine tool, and bears the structural weight of the peripheral gear ring through physical contact.

[0030] Figure 4 Showing Figure 2 The magnified view of the middle C region clearly reveals the physical mechanical structure of the "axial displacement absorption" and "dual fluid flow" in the upper feed pipeline; The cross-sectional structure shows that the upper hollow tube 40 and the lower rotating tube 42 are physically separated in the vertical direction, without direct rigid connection. Instead, they are connected by multiple sets of telescopic rods 44 evenly distributed circumferentially between their end faces, forming a sliding transmission frame. During the physical action of the machine tool closing and pressing down, the multiple sets of telescopic rods 44 are compressed and undergo axial sliding contraction, absorbing the redundant stroke of the upper spindle box moving downward, thus physically cutting off the rigid impact force transmitted downward. When the motor drives the pipeline to rotate, the multiple sets of telescopic rods 44 act as a solid circumferential force-bearing entity, rigidly transmitting the rotational torque at the top to the lower rotating tube 42, achieving a mechanical separation of "axial displacement absorption and circumferential torque transmission." Between the internal cavities of the two pipe sections, a flexible hose 43 that can be axially folded is fitted. Under the rigid protection of the external telescopic rod 44 frame, the internal hose 43 is completely isolated from the physical pulling of the circumferential rotational shear force, and is only responsible for crossing the dynamic expansion gap between the upper and lower pipes to safely and leak-free introduce the high-pressure coolant into the interior of the rotating pipe 42. Meanwhile, a transverse water outlet 41 is directly drilled on the side wall of the hollow tube 40. When the fluid inside the tube flows downward, some of the high-pressure coolant is diverted here. Physically thrown by the centrifugal force generated by the high-speed rotation of the tube, it is forcibly sprayed out from the water outlet 41 and directly sprayed onto the surrounding processing area, forming the upper external cooling channel of the machine tool.

[0031] Figure 5 It demonstrates the concentric nesting and physical assembly relationship of the core interlayer working area of ​​the edge grinding machine in the horizontal direction; The horizontal mechanical transmission structure of the machine tool can be clearly seen from this top cross-section: the central sun gear 80 is located on the innermost side, and the outer internal gear ring 90 surrounds it on the outermost side, together forming the inner and outer rigid boundaries of the planetary transmission. The planetary plate 70 is clamped in the annular tooth gap between the central sun gear 80 and the outer internal gear ring 90. Multiple through-circumferential circular cavities are machined on the disc body of the planetary plate 70, and each annular workpiece 60 is physically placed and confined inside these cavities, bearing the end face extrusion and friction cutting of the upper and lower grinding discs; In the physical operation of the machine tool when it is powered on, the central sun gear 80 and the outer internal gear ring 90 are provided with rotational torque by their respective independent bottom motors, generating a preset speed difference and direction difference. The planetary plate 70 is forced to move by the inner and outer tooth surfaces, carrying the internal annular workpiece 60 to perform a compound sliding of revolution and rotation on the lower grinding disc surface, realizing all-round mechanical grinding of the end face; The circular hole in the center of the diagram corresponds to the rotating tube 42 above and the penetrating space at the bottom. This area is a vertical channel for the forced downward transmission of rotational power from the top of the machine tool and for the forced injection of high-pressure coolant into the lower layer. This diagram visually illustrates the horizontal geometry and force path of the multi-axis differential drive of the machine tool.

[0032] Figure 6 The key features are shown in the fluid introduction path at the top of the machine tool, and the physical assembly and mating relationship between the rotary joint 11 and the stationary water inlet pipe and the lower rotary pipe; As can be clearly seen from the force and flow arrows in the schematic diagram, the lifting spindle 20 at the top of the machine tool is responsible for providing vertical downward mechanical thrust to drive the entire machine to close the mold and press down. Below the spindle is the core rotary joint 11, whose side port is physically fixedly connected to the stationary external water inlet pipe 10, while its bottom port is rotatably connected to the hollow tube 40 fitted below. In the actual mechanical operation of the machine tool, the hollow tube 40 is driven by the upper motor to rotate in a circular motion, as shown by the circular arrow in the figure. At the same time, the external high-pressure coolant is forced into the rotary joint 11 through the horizontal direction of the external water inlet pipe 10. Through the solid dynamic sealing component inside the rotary joint 11, the water flow completes the physical transition from a "static environment" to a "high-speed rotating environment", and the water flow direction is then turned vertically downward, as shown by the straight arrow in the figure, and is forced into the internal channel of the hollow tube 40; This diagram visually illustrates how, with the pipeline continuously rotating, the machine tool utilizes a physical mechanical rotary joint to force external fluid into the internal rotary transmission frame, providing an uninterrupted water supply for the bottom layer's dynamic pressure lifting and physical cooling.

[0033] Figure 7 The key features are the vertical solid dimension relationship between the planetary plate 70 and the annular workpiece 60 in the assembled state, as well as the cross-sectional geometry of the bottom hydrodynamic fluid channel 71; First, a direct comparison of the thickness of the solid components in the vertical direction clearly shows that the thickness of the planetary plate 70 is machined to be strictly smaller than the thickness of the annular workpiece 60 nested within it. Both the upper and lower end faces of the annular workpiece 60 protrude significantly beyond the upper and lower surfaces of the planetary plate 70. This extremely precise dimensional chain relationship ensures that when the grinding disc on the machine tool applies downward pressure to close the mold, the heavy-duty vertical thrust is directly pressed against the end face of the annular workpiece 60, rather than being distributed or mistakenly pressed onto the planetary plate 70, which serves as the carrier. Secondly, the cross-sectional view on the bottom surface of the planetary plate 70 clearly reveals the depth gradient of the hydrodynamic fluid channel 71. This fluid channel exhibits a solid sloping structure in the depth direction: one end is concave to the deepest point, serving as the inflow end to accommodate the fluid, and the depth gradually decreases along the channel's extension direction until it is completely flush with the bottom plane of the planetary plate 70 at the tail end. When the bottom plates of the machine tool undergo high-speed relative sliding, the coolant is forced into the deepest part of this channel, and then, under mechanical pull, is forced towards the extremely narrow sloping tail end. This physically wedge-shaped contraction space generates strong volume compression of the fluid, thus instantly producing an upward fluid thrust that lifts the planetary plate.

[0034] Figure 8 The key features showcased are the solid flow channel geometry and fluid dynamics guidance structure on the bottom surface of the planetary plate 70; As can be seen from the bottom-view planar projection, the central cavity of the planetary plate 70 contains a physically fitted annular workpiece 60. Around this central bearing area, the bottom surface of the planetary plate 70 is machined with multiple curved radially distributed hydrodynamic fluid grooves 71 in an array. During the physical operation of the machine tool, the high-pressure coolant is first vertically injected through the guide hole 75 penetrating the disc body, falling directly into the water-facing end 72 at the deepest point of the dynamic pressure fluid tank 71. As the bottom discs undergo high-speed relative sliding rotation, the fluid is forced to be dragged by tangential mechanical friction and shear force, and pushed and surged outwards towards the tail end 73 along the equal-width dynamic pressure fluid tank 71. Due to the gradually shallowing slope structure at the bottom of the tank, the fluid is subjected to strong volume compression during the pushing process, and an upward fluid support thrust is instantly generated. Simultaneously, at the tail end 73 of the dynamic pressure fluid tank 71, there is an unloading micro-channel 74 extending towards the outermost edge of the disc. Due to the significant abrupt reduction in the flow cross-sectional area, the unloading micro-channel 74 physically constitutes a mechanical throttling valve, ensuring that the fluid inside the dynamic pressure fluid tank 71 can hold and maintain a positive pressure sufficient to support the heavy load above. Subsequently, the coolant, continuously and forcibly expelled outward, washes away the metal and grinding wheel debris generated by the friction on the bottom surface to the outside of the machine tool, completing the closed loop of physical action from "volume compression to generate force" to "forced physical chip removal".

[0035] Next, Examples 1-3 will be described; Example 1 This embodiment provides a ring-shaped workpiece edge grinding machine with a multi-axis drive chassis and telescopic tolerance feed structure. Its overall mechanical structure mainly includes an upper grinding disc 50, a lower grinding disc 100, a central sun gear 80, an outer internal gear ring 90, and a planetary plate 70 positioned between the central sun gear 80 and the outer internal gear ring 90. The planetary plate 70 has a cavity on its surface to accommodate the ring-shaped workpiece 60. To ensure that the downward grinding pressure can completely bypass the carrier and directly press against the end face of the workpiece, the overall thickness of the planetary plate 70 is configured to be strictly less than the thickness of the ring-shaped workpiece 60.

[0036] In the transmission section at the bottom of the machine tool, power is provided by independent and coaxially nested drive components, and the specific mechanical transmission process is as follows: The output shaft of the lower grinding disc drive motor 130 rotates, driving the lower grinding disc transmission component 131 to operate. The lower grinding disc transmission component 131 transmits rotational torque to the outer wall of the lower grinding disc main shaft 110, which has a sleeve structure. The lower grinding disc main shaft 110 rotates under the radial and axial support of the lower grinding disc main shaft bearing seat 170, thereby directly driving the lower grinding disc 100 fixed on its top to rotate, providing the bottom layer of rotational linear velocity for the edge grinding operation. At the same time, the output shaft of the sun gear drive motor 140 rotates, directly transmitting rotational torque to the sun gear main shaft 120. The sun gear main shaft 120 coaxially passes through the internal channel of the lower grinding disc main shaft 110, and its top end drives the central sun gear 80 to rotate independently.

[0037] On the periphery, the output shaft of the internal gear ring drive motor 150 drives the internal gear ring drive gear 151 to rotate. The teeth of the internal gear ring drive gear 151 mesh with the outer edge of the annular base 91 at the bottom of the peripheral internal gear ring 90, pushing and pulling the peripheral internal gear ring 90 to rotate. The annular base 91 is supported on the annular support step 92 at the bottom of the machine tool, and an annular wear-resistant belt 160 is sandwiched between the contact surfaces of the two to withstand sliding friction. Under the physical drive of the aforementioned speed difference, the planetary plate 70 is forced to move by the inner and outer tooth surfaces, generating a composite motion of revolution and rotation between the grinding discs. The upper feed and transmission part of the machine tool is responsible for providing the vertically downward grinding thrust, the top rotational power, and the layered fluid channels.

[0038] The lifting spindle 20 moves downward along the vertical guide rail, directly pushing the spindle box 21 down. The upper grinding disc drive motor 30 is fixed inside the spindle box 21, and its output shaft drives the upper grinding disc transmission gear set 31 to rotate, transmitting the rotational torque to the hollow tube 40. The hollow tube 40 drives the upper grinding disc 50, which is fixed on the outer wall, to rotate synchronously. To avoid axial mechanical collision when the upper and lower parts are closed, an independent rotating tube 42 is coaxially arranged directly below the hollow tube 40.

[0039] The bottom of the rotating tube 42 is rotatably connected to the positioning blind hole bearing seat 81 via an internal bearing, and a rotary dynamic seal structure is connected in series at the connection to ensure fluid sealing. Between the bottom end face of the hollow tube 40 and the top end face of the rotating tube 42, multiple sets of telescopic rods 44 are evenly distributed and fixedly connected along the circumference. These multiple sets of telescopic rods 44 adopt a sliding fit structure of guide posts and guide sleeves, forming a circumferential transmission frame. Regarding the fluid flow path, external high-pressure fluid is injected through the external water inlet pipe 10, passes through the rotary joint 11 inside the spindle box 21, and enters the interior of the hollow tube 40.

[0040] The fluid is transported downwards in a stratified flow: the first stream of fluid passes through the water outlet 41 on the side wall of the hollow tube 40 and sprays outwards, directly onto the gap between the upper grinding disc 50 and the top surface of the planetary plate 70; the second stream of fluid continues downwards.

[0041] A flexible hose 43 is fixedly connected between the inner cavities of the hollow tube 40 and the rotating tube 42. The flexible hose 43 has a corrugated structure and can withstand axial folding. The second fluid flows through the flexible hose 43 into the rotating tube 42, and is blocked by the bottom dynamic seal structure. It can only pass downward through the positioning blind hole bearing seat 81 into the interior of the sun gear main shaft 120, providing a fluid source for the bottom.

[0042] In addition, in order to provide physical support for the planetary plate 70 when the equipment is stopped, a first limiting step 82 with an upward protrusion is machined at the outer base edge of the central sun gear 80, and a second limiting step 93 with an upward protrusion is machined at the inner base edge of the outer internal gear ring 90; a fixed height difference is left between the top surface of the above two and the top surface of the lower grinding disc 100.

[0043] The complete operating steps for this device are as follows: First, a circular workpiece 60 is placed inside the cavity. The lifting spindle 20 is operated to push the spindle box 21 downwards, causing the hollow tube 40 and the upper grinding disc 50 to descend accordingly. Because the bottom end of the lower rotating tube 42 is restricted from downward displacement by the positioning blind hole bearing seat 81, multiple sets of telescopic rods 44 are compressed and undergo axial sliding contraction, causing the internal flexible hose 43 to fold axially simultaneously. This sliding structure absorbs the downward mechanical stroke. At this time, the planetary plate 70, due to its own weight, rests directly on the first limiting step 82 and the second limiting step 93.

[0044] Power is sequentially supplied to the lower grinding disc drive motor 130, the sun gear drive motor 140, the internal gear ring drive motor 150, and the upper grinding disc drive motor 30. The bottom transmission components begin to operate, and simultaneously, the hollow tube 40 at the top begins to rotate. Multiple sets of telescopic rods 44, acting as circumferential force transmission entities, rotate synchronously with the hollow tube 40, and forcibly transmit the rotational torque to the rotating tube 42 below. Driven by this framework, the flexible hose 43 is protected from circumferential torsional shear force. The planetary plate 70 begins to slide and rotate on the limiting step.

[0045] After the rotating assembly operates smoothly, open the water supply valve of the external water inlet pipe 10. The fluid flows along the hose 43 across the dynamic gap and into the interior of the bottom sun gear spindle 120. The fluid instantly rushes into the bottom surface of the planetary plate 70, generating an upward fluid support force that lifts the planetary plate 70 from the first limit step 82 and the second limit step 93, and the equipment officially enters the fluid suspension edge grinding state.

[0046] After the edge grinding process is completed, first close the valve of the external water inlet pipe 10, and then cut off the power to each drive motor. After the fluid thrust is lost, the planetary plate 70 returns to the limit step. After all the rotating gears and bushings have completely stopped rotating, operate the lifting spindle 20 to pull the spindle box 21 upward. The hollow tube 40 rises accordingly, and multiple sets of telescopic rods 44 and hoses 43 are stretched back to their original positions. The upper grinding disc 50 is lifted, releasing the internal physical space. Finally, the engineer removes the processed workpiece.

[0047] Example 2 Based on the mechanical transmission component of Embodiment 1, this embodiment further discloses the flow channel geometry on the bottom surface of the planetary plate 70, and how this structure converts the relative sliding of the mechanical components into an upward thrust in the physical operation process.

[0048] To generate an upward fluid thrust on the bottom surface, the bottom surface of the planetary plate 70 is machined with a plurality of hydrodynamic fluid grooves 71 at intervals along the circumference. In the overall planar arrangement, the hydrodynamic fluid grooves 71 are arranged radially with the center of the planetary plate 70 as the reference point, and the water-facing end 72 is positioned towards the inner edge of the planetary plate 70, while the tail end 73 faces towards the outer edge of the planetary plate 70. This internal and external arrangement conforms to the actual physical motion direction of the coolant being thrown outward by centrifugal force, preventing fluid interruption at the bottom surface.

[0049] From the perspective of planar projection geometry, the hydrodynamic fluid channel 71 is a long strip with equal width at the water-facing end 72 and the tail end 73. This equal width feature directly corresponds to the straight milling tool path during workshop manufacturing. In the depth direction, the bottom of the hydrodynamic fluid channel 71 is sloping: the concave depth is the greatest at the water-facing end 72, and it gradually becomes shallower towards the tail end 73 along the fluid flow direction, until it is completely flush with the bottom surface of the planetary plate 70 at the tail end 73.

[0050] Between two adjacent hydrodynamic fluid channels 71, the bottom surface of the planetary plate 70 retains a flat solid bearing surface. When the fluid is compressed, this solid bearing surface acts as a physical water-blocking boundary on both sides of the hydrodynamic fluid channel 71, restricting lateral leakage of the fluid and forcing the fluid to flow unidirectionally only along the slope direction.

[0051] In terms of fluid introduction, the planetary plate 70 has guide holes 75 drilled through its top and bottom surfaces. The bottom opening of the guide holes 75 is directly aligned with and falls into the water-facing end 72 of the dynamic pressure fluid tank 71, forming a vertical water injection channel. In terms of fluid discharge, the bottom surface of the planetary plate 70 is further machined with unloading micro-grooves 74. The inner end of the unloading micro-grooves 74 is connected to the tail end 73 of the dynamic pressure fluid tank 71, while the outer end extends outward and penetrates to the outermost edge of the planetary plate 70. In terms of physical cross-sectional dimensions, the flow cross-sectional area of ​​the unloading micro-grooves 74 is smaller than the flow cross-sectional area of ​​the dynamic pressure fluid tank 71 at its deepest point in the water-facing end 72, thus forming a physical throttling valve.

[0052] During the lifting process of the machine tool, the high-pressure coolant inside the sun gear spindle 120 is sprayed outward through the radial diversion hole 121 to the inner ring area at the bottom of the planetary plate 70. Under the mechanical friction force of the relative rotation between the grinding disk and the planetary plate 70, the fluid is forced into the deepest water-facing end 72 of the hydrodynamic fluid groove 71 by the guide hole 75 in the tangential direction of the relative rotation. As the disk continues to slide relative to the planetary plate, the fluid is forced to push along the equal-width hydrodynamic fluid groove 71 towards the shallow tail end 73. Due to the axial space being continuously mechanically compressed by the slope of the groove bottom, and the fact that both sides are completely blocked by the solid bearing surface, the fluid is subjected to strong volume compression in the closed space. This real mechanical compression instantly generates an upward fluid thrust between the bottom surface of the planetary plate 70 and the top surface of the lower grinding disk 100.

[0053] Simultaneously, due to the abrupt reduction in the flow cross-sectional area of ​​the unloading micro-groove 74 connected to the tail end 73, it acts as a physical throttling and pressure-maintaining valve, allowing the dynamic pressure fluid groove 71 to retain and maintain a positive fluid pressure sufficient to support the planetary plate 70 and the downward pressure of the grinding edge above. Finally, the continuously compressed fluid overcomes resistance and is discharged outward from the unloading micro-groove 74, and the outflowing coolant washes away the debris generated by the friction on the bottom surface, achieving mechanical chip removal and physical cleaning of the working surface.

[0054] Example 3 This embodiment, based on the mechanical transmission structure and flow channel geometry of the aforementioned embodiments, discloses the timing of actions between the transmission components and the force-bearing components during the operation of the annular workpiece grinding machine, as well as the underlying physical operating principles. The machine tool's operation process is divided into the following four stages: Phase 1: First, the annular workpiece 60 is placed into the cavity of the planetary plate 70. Under its own weight, the planetary plate 70 rests on the first limiting step 82 of the central sun gear 80 and the second limiting step 93 of the outer internal gear ring 90. Then, the lifting spindle 20 is operated to push the spindle box 21 downwards, causing the upper grinding disc 50 to sink accordingly. When the bottom end of the rotating tube 42 is inserted into the positioning blind hole bearing seat 81, the multiple sets of telescopic rods 44 between the hollow tube 40 and the rotating tube 42 are compressed and undergo axial sliding contraction. The mechanical principle of this action is to utilize the sliding freedom of the multiple sets of telescopic rods 44 to physically isolate the downward displacement of the upper grinding disc 50 from the axial load of the bottom bearing. This sliding mold-closing mechanism can absorb the redundant downward stroke of the spindle box 21, ensuring that while the upper grinding disc 50 is pressing the workpiece, it does not directly transmit the rigid impact force in the vertical direction to the bottom sun gear spindle 120, thus protecting the bottom bearing from damage.

[0055] The second stage: Before connecting the drive motor, first open the water supply valve of the external water inlet pipe 10. The fluid passes through the hose 43 and the rotating pipe 42, and finally is sprayed from the radial diversion hole 121 onto the bottom surface of the planetary plate 70. The principle of this action is: using the initial fluid pressure provided by the external water pump, a layer of static pressure water with physical thickness is forcibly filled between the bottom surface of the planetary plate 70 and the limiting step. According to the principle of fluid pressure transmission, the fluid generates a uniform upward thrust within the sealed bottom surface gap. The purpose of this process is to transform the direct metal contact of the bottom surface of the planetary plate 70 into shear friction within the liquid during the mechanical rotation start-up phase, avoiding scratches or seizing of the metal surface at the moment of heavy-load start-up.

[0056] Third stage: After water filling is completed, the power supply of the drive motor is turned on in sequence. The rotational torque at the top is transmitted rigidly to the rotating tube 42 below through multiple sets of telescopic rods 44 as a circumferential transmission frame along the hollow tube 40; Multiple sets of telescopic rods 44, through a circumferentially distributed guide column structure, can withstand high-power circumferential shear force while maintaining axial free sliding, ensuring the continuous transmission of rotational power between the two pipe sections. As the disc rotates at high speed, fluid is scraped into the water-facing end 72 of the dynamic pressure fluid channel 71 by the guide hole 75. Because the slope at the bottom of the channel becomes sharply shallower towards the tail end 73, and is physically blocked on both sides by flat solid bearing surfaces, the fluid is subjected to intense volumetric compression within the continuously narrowing wedge-shaped space. This substantial compression action converts kinetic energy into upward fluid pressure, generating a supporting force sufficient to overcome the edge-grinding pressure, completely lifting the planetary plate 70 from the step. At this time, the small cross-sectional feature of the unloading microchannel 74 acts as a throttling and pressure-maintaining mechanism, maintaining the physical rigidity of the bottom fluid support layer.

[0057] Phase 4: After the operation is completed, disconnect the motor power and close the water supply valve after the speed drops. The planetary plate 70 returns to the step due to the loss of thrust from the bottom surface. The mechanical extraction principle in this phase is as follows: the lifting spindle 20 pulls the spindle box 21 upward, and the hollow tube 40 drives multiple sets of telescopic rods 44 to stretch in the opposite direction. When the sliding reaches the maximum physical limit dead point of the multiple sets of telescopic rods 44, the upward pulling force changes from "free sliding" to "rigid traction". At this time, the pulling force overcomes the physical resistance of the seal at the positioning blind hole bearing seat 81, and pulls the rotating tube 42 out smoothly. This limit extraction mechanism ensures that the upper and lower pipelines can be lifted off the ground as a whole when the mold is opened, reserving sufficient physical space for the addressing and insertion of the next cycle.

[0058] Implementation 4 This embodiment discloses an alternative to the "telescopic tolerance and fluid flow structure" in the upper feed and transmission mechanism. This embodiment replaces the hose 43 in the previous embodiment with a rigid sliding sealing pipe to accommodate higher pressure coolant environments.

[0059] In order to maintain fluid sealing when the hollow tube 40 and the rotating tube 42 are axially relative to each other in the fluid-through structure, this embodiment eliminates the internal hose 43 and replaces it with a sleeve-type sliding sealing assembly.

[0060] The specific structure is as follows: a rigid inner sliding tube is coaxially fixedly connected to the bottom of the inner cavity of the hollow tube 40, and an outer sliding tube with a slightly larger aperture is coaxially fixedly connected to the top of the inner cavity of the rotating tube 42. The lower end of the inner sliding tube is inserted into the outer sliding tube with a clearance fit, and multiple high-pressure resistant dynamic sealing rings (such as Y-type sealing rings or step seals) are installed circumferentially within the overlapping annular gap between the two.

[0061] During the mold closing and pressing action of the machine tool, the spindle box 21 drives the hollow tube 40 to descend. The multiple sets of external telescopic rods 44 slide and retract to absorb redundant mechanical stroke, while the internal inner sliding tube is inserted deeper into the outer sliding tube. During this dynamic sliding process, the dynamic sealing ring tightly adheres to the tube wall, ensuring that the high-pressure fluid does not leak when crossing these two sections of the tube.

[0062] The beneficial effects of this solution are as follows: When the processing environment requires extremely high-pressure fluid to flush away large particles of waste, flexible hoses are prone to fatigue cracking or radial expansion under long-term alternating stress from high water pressure and axial folding. The pure rigid metal structure employing a sleeve-type sliding seal assembly significantly improves the structural strength and service life of the internal flow channels under extremely high fluid pressure.

[0063] Example 5 This embodiment discloses an alternative to the hydrodynamic suspension structure on the bottom surface of the planetary plate 70. This embodiment replaces the continuously varying depth, sloping hydrodynamic fluid channel 71 of the aforementioned embodiment with a stepped, abruptly changing fluid channel to simplify the manufacturing process.

[0064] In order to generate an upward fluid thrust on the bottom surface, in this embodiment, the fluid channel on the bottom surface of the planetary plate 70 is divided into two regions with different flush depths along the flow direction, namely a stepped dynamic pressure fluid channel, which is similar to the Rayleigh step bearing structure in fluid mechanics.

[0065] From a geometric cross-sectional perspective, this stepped hydrodynamic fluid channel is divided into a "deep channel zone" near the center and a "shallow channel zone" near the edge. The deep channel zone and the shallow channel zone are not connected by a slope, but by a rigid abrupt connection made by a vertical water-retaining step surface. The other end of the shallow channel zone is directly connected to the aforementioned unloading microchannel 74.

[0066] During the lifting process of the machine tool, high-pressure coolant is first injected into the larger deep groove area through the guide hole 75. As the discs rotate relative to each other, the fluid is dragged by the mechanical friction force in the tangential direction and forced to surge into the shallow groove area. When the fluid flows through the vertical water-blocking step surface, due to the rapid and sudden physical reduction of the flow cross-sectional area, the fluid velocity increases sharply and is subjected to strong physical compression, i.e., the step throttling effect. This sudden contraction of the fluid channel can also generate extremely high hydrodynamic pressure instantaneously near the step, thereby effectively generating an upward supporting thrust to lift the planetary plate 70.

[0067] The beneficial effects of this solution are as follows: compared with the continuous gradient ramp groove which requires high machining accuracy and multi-axis linkage milling, the stepped hydrodynamic fluid groove can be completed by only two plane millings of different depths, which greatly reduces the machining difficulty and manufacturing cost of the bottom surface of the planetary plate, while still providing the hydrodynamic bearing capacity to meet the requirements of heavy-load suspension.

[0068] In the description of this specification, the references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0069] The above description is merely an example and illustration of the concept of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described or use similar methods to replace them, as long as they do not deviate from the concept of the invention or exceed the scope defined in the claims, they should all fall within the protection scope of the present invention.

Claims

1. A ring-shaped workpiece edge grinding machine, mainly comprising an upper grinding disc (50), a lower grinding disc (100), a central sun gear (80), a peripheral internal gear ring (90), and a planetary plate (70) disposed between the central sun gear (80) and the peripheral internal gear ring (90), wherein the planetary plate (70) has a cavity on its surface for accommodating a ring-shaped workpiece (60), characterized in that, include: The bottom transmission mechanism includes a lower grinding disc spindle (110) and a sun gear spindle (120) passing through the interior of the lower grinding disc spindle (110); a lower grinding disc drive motor (130) drives the lower grinding disc spindle (110) and the lower grinding disc (100) to rotate, a sun gear drive motor (140) drives the sun gear spindle (120) and the central sun gear (80) to rotate; and an internal gear ring drive motor (150) drives the outer internal gear ring (90) to rotate. The upper feed and transmission mechanism includes a spindle box (21) that moves up and down along a vertical track, a hollow tube (40) installed in the spindle box (21), and a rotating tube (42) located below the hollow tube (40); the bottom of the rotating tube (42) is rotatably connected to a positioning blind hole bearing seat (81) located at the top of the sun gear spindle (120) via a bearing; the upper grinding disc drive motor (30) drives the hollow tube (40) and the upper grinding disc (50) to rotate; The telescopic tolerance and fluid passage structure includes multiple sets of telescopic rods (44) fixedly connected between the bottom end face of the hollow tube (40) and the top end face of the rotating tube (42); a hose (43) is fixedly connected between the internal cavities of the hollow tube (40) and the rotating tube (42); external high-pressure fluid enters the rotating tube (42) through the hollow tube (40) and the hose (43), and passes through the positioning blind hole bearing seat (81) to enter the interior of the sun gear spindle (120); The hydrodynamic suspension structure has several hydrodynamic fluid grooves (71) spaced circumferentially on the bottom surface of the planetary plate (70); the sun gear spindle (120) has a radial diversion hole (121), which injects high-pressure fluid into the bottom surface of the planetary plate (70). The fluid enters the hydrodynamic fluid groove (71) under the shear force of the relative rotation of the grinding disk and the planetary plate (70) and is axially compressed, generating an upward hydrodynamic support force.

2. The ring-shaped workpiece edge grinding machine according to claim 1, characterized in that: The machine tool is equipped with a lifting spindle (20) on the top, which is connected to the spindle box (21) to drive its lifting and lowering; the external water inlet pipe (10) is connected to the top of the hollow tube (40) through a rotary joint (11) set in the spindle box (21).

3. The ring-shaped workpiece edge grinding machine according to claim 1, characterized in that: The hollow tube (40) has a water outlet (41) on its side wall, and the water outlet (41) faces the area between the upper grinding disc (50) and the top surface of the planetary plate (70).

4. The ring-shaped workpiece edge grinding machine according to claim 1, characterized in that: The hydrodynamic fluid channel (71) is a long strip with the same width at the water-facing end (72) and the tail end (73) in a planar projection; in the depth direction, the hydrodynamic fluid channel (71) is the deepest at the water-facing end (72) and gradually becomes shallower towards the tail end (73) until it is a slope that is flush with the bottom surface of the planetary plate (70) at the tail end (73).

5. The annular workpiece edge grinding machine according to claim 4, characterized in that: A flush solid bearing surface is maintained between two adjacent hydrodynamic fluid tanks (71).

6. The annular workpiece edge grinding machine according to claim 4, characterized in that: The planetary plate (70) has a guide hole (75) that penetrates the top and bottom surfaces, and the bottom opening of the guide hole (75) is located in the water-facing end (72) of the dynamic pressure fluid tank (71).

7. The annular workpiece edge grinding machine according to claim 4, characterized in that: The bottom surface of the planetary plate (70) is also provided with an unloading micro-groove (74). One end of the unloading micro-groove (74) is connected to the tail end (73), and the other end extends to the edge of the planetary plate (70). The flow cross-sectional area of ​​the unloading micro-groove (74) is smaller than the flow cross-sectional area of ​​the deepest part of the dynamic pressure fluid groove (71).

8. The ring-shaped workpiece edge grinding machine according to claim 1, characterized in that: The outer base edge of the central sun gear (80) is provided with an upwardly protruding first limiting step (82), and the inner base edge of the peripheral inner gear ring (90) is provided with an upwardly protruding second limiting step (93); there is a preset height difference between the top surface of the first limiting step (82) and the second limiting step (93) and the top surface of the lower grinding disc (100).

9. The ring-shaped workpiece edge grinding machine according to claim 1, characterized in that: The overall thickness of the planetary plate (70) is less than the thickness of the annular workpiece (60).

10. The ring-shaped workpiece edge grinding machine according to claim 1, characterized in that: The bottom of the peripheral internal gear ring (90) is provided with an annular base (91), and the bottom of the machine tool is provided with an annular support step (92). An annular wear-resistant belt (160) is sandwiched between the annular base (91) and the annular support step (92). The output end of the internal gear ring drive motor (150) is provided with an internal gear ring drive gear (151), and the internal gear ring drive gear (151) meshes with the outer edge of the annular base (91).

Images