An apparatus for superfinishing an aero-vane by abrasive flow

Abstract

An equipment for super-precision machining of aviation impeller by abrasive grain flow is composed of lifting and rotating device part, clamp part, connecting part, stirring device, constant temperature control device and workbench auxiliary part, characterized in that the lifting and rotating device is installed on the workbench, the tank is installed below the workbench, the water tank of the constant temperature control device is installed below the workbench, the pipeline part is installed to the tank, the motor of the stirring device is installed below the workbench, the stirring paddle is installed in the tank, and the clamp part is installed on the lifting and rotating device through the shaft coupling. The equipment has the advantages that the abrasive constant temperature control system is added, the real-time monitoring and automatic control of the abrasive temperature are realized, the viscosity and flowability of the abrasive are stabilized, the consistency and surface quality of the impeller machining are effectively improved, the automatic clamp is adopted, the accurate clamping and efficient flow guiding of the impeller are realized, the clamping efficiency and machining safety can be greatly improved by cooperating with the automatic clamping action, and the equipment is especially suitable for abrasive grain flow finishing of small aviation impellers and other precision workpieces.

Description

Technical Field

[0001] This invention relates to the field of abrasive flow machining technology, specifically to a device for ultra-precision machining of aerospace impellers using abrasive flow. Background Technology

[0002] Small aero-engine impellers are core components ensuring engine aerodynamic efficiency and service life, widely distributed in critical flow channels such as fans, compressors, and turbines. The surface roughness, profile accuracy, and integrity of the blades directly affect the airflow boundary layer state and flow characteristics, thus determining the engine's thrust performance, fuel economy, and fatigue reliability. Aero-engine blades often have complex curved and twisted surface structures, and turbine blades are densely covered with film cooling holes and internal flow channels. Traditional methods such as manual polishing and CNC grinding are difficult to use to achieve uniform finishing of the profile and micro-pore areas, and are prone to causing profile deviations and micro-crack damage. Therefore, abrasive flow polishing is selected for precision finishing.

[0003] Abrasive flow finishing, also known as fluid polishing or extrusion grinding polishing, is a precision finishing process for complex cavities, micro-holes, and irregular curved surfaces. Its principle involves using a viscoelastic abrasive medium that flows reciprocally along the workpiece surface under pressure, causing the abrasive particles to continuously perform micro-cutting and rolling grinding, thereby achieving deburring, rounding, and mirror polishing. This process can process complex internal cavities and micro-hole structures that are difficult to reach with traditional processes. It offers good processing uniformity and repeatability, can be automated, and provides excellent surface integrity, strong parameter controllability, and precise control over material removal and surface roughness. However, existing abrasive flow machining equipment has obvious defects in long-term continuous processing: the viscoelastic abrasive medium will continuously generate heat under the action of reciprocating extrusion and flow shear, which will lead to an increase in the temperature of the abrasive, which in turn will cause a decrease in viscosity and a decrease in the suspension stability of the abrasive, resulting in fluctuations in processing efficiency, a decrease in the uniformity of surface roughness, and even a deterioration of abrasive performance and out-of-tolerance of blade profile dimensional accuracy due to excessive temperature. It is difficult to meet the high precision and high consistency processing requirements of aerospace blades. Therefore, it is urgent to add an abrasive constant temperature cooling system to the existing equipment. Summary of the Invention

[0004] To address the aforementioned shortcomings, the purpose of this invention is to provide a device for ultra-precision machining of aerospace blades using abrasive flow, which features a simple structure, stable performance, and real-time adjustable abrasive temperature.

[0005] To achieve the above objectives, this invention adopts the following technical solution: A device for ultra-precision machining of aerospace blades using abrasive flow, characterized in that: the device comprises a lifting and rotating device, a clamping device, a connecting device, a stirring device, a constant temperature control device, and an auxiliary worktable. The worktable is horizontally placed, with the lifting and rotating device positioned close to the right edge of the worktable. The lifting and rotating device comprises a lifting cylinder, a pad, a connecting plate, an angular contact ball bearing mounting seat one, an angular contact ball bearing one, a spline drive shaft, an angular contact ball bearing two, an angular contact ball bearing mounting seat two, an auxiliary tripod, a small reducer, a small reducer mounting bracket, a pulley one, a pulley two, a belt, screws, and bolts. The clamping device comprises a driven shaft, a tripod connecting seat, grippers, bolts, and nuts. The connecting device comprises a coupling and fixing bolts. The stirring device comprises a stirring propeller, a deep groove ball bearing one, a deep groove ball bearing two, a deep groove ball bearing mounting seat one, a deep groove ball bearing mounting seat two, a motor, a large pulley, a small pulley, a V-belt, screws, and bolts. The temperature control device consists of a water tank, a water pump, inlet pipe 1, inlet pipe 2, inlet pipe 3, return pipe, water pipe interface, temperature sensor, temperature controller, and AC contactor. The auxiliary part of the workbench consists of a workbench, material box, and fixing bolts.

[0006] Furthermore, as a preferred embodiment, the auxiliary tripod has a through hole at its bottom and is connected to the worktable via bolts; the cylinder has a through hole at its bottom and is connected to the worktable via bolts; the pad has a threaded hole at its center and is connected to the cylinder telescopic rod via threads; the pad has a countersunk hole at its top and is connected to the threaded hole on the connecting plate via screws; the connecting plate has a round hole that mates with an angular contact ball bearing mounting seat one; the angular contact ball bearing mounting seat one has countersunk holes around its perimeter and is connected to the through hole on the connecting plate via screws; the angular contact ball bearing mounting seat one has mounting holes and is connected to the angular contact ball bearing one via clearance fit; the cylindrical shaft of the drive shaft is connected to the angular contact ball bearing one via clearance fit; the splined shaft portion of the drive shaft mates with the splined hole of the bushing; the bushing has a keyway and is connected to a pulley one via a key; the pulley one is axially fixed to the drive shaft via a shoulder positioning; the drive shaft is connected to an angular contact ball bearing two via clearance fit; and the angular contact ball bearing two is connected to an angular contact ball bearing mounting seat two via clearance fit.

[0007] Pulley 1 and Pulley 2 are connected by a belt to transmit power, which is output by a small reducer. The small reducer is fixed to the workbench by a small reducer mounting bracket. The bottom of the small reducer mounting bracket has a through hole and is connected to the workbench by bolts.

[0008] Furthermore, as a preferred embodiment, the first deep groove ball bearing mounting base is provided with a threaded hole and is fixed to the material box by screws. The first deep groove ball bearing is connected to the first deep groove ball bearing mounting base by clearance fit. The spiral agitator is connected to the first deep groove ball bearing by clearance fit. The spiral agitator is connected to the second deep groove ball bearing by clearance fit. The second deep groove ball bearing is connected to the second deep groove ball bearing mounting base by clearance fit. The second deep groove ball bearing mounting base is provided with a threaded through hole and is connected to the material box by bolts. The central shaft of the spiral agitator is provided with a keyway and is connected to the large pulley by a flat key. The small pulley is provided with a keyway and is connected to the motor output shaft by a key. The bottom of the motor is provided with a through hole and is fixed to the worktable by bolts.

[0009] Furthermore, as a preferred embodiment, the temperature sensor has a through hole and is mounted on the side wall of the abrasive box with screws. The probe extends into the abrasive to collect temperature signals in real time. The temperature sensor is connected to the temperature controller via three wires. The temperature controller has a through hole at its bottom and is fixed to the electrical control panel of the workbench with screws. The temperature controller is connected to an AC contactor via wires. The coil of the AC contactor is switched on and off according to the output signal of the temperature controller, thereby controlling the engagement and disengagement of its main contacts to achieve on / off control of the power supply circuit of the water pump.

[0010] Furthermore, as a preferred embodiment, the material box mounting base is provided with a through hole and connected to the worktable by fixing bolts, and the bottom of the material box is provided with a discharge port that cooperates with a plug to realize the recycling of abrasive.

[0011] The advantages of this invention are:

[0012] This invention achieves real-time monitoring and automatic control of abrasive temperature by adding an abrasive constant temperature control system, which stabilizes abrasive viscosity and flowability, effectively improving the consistency and surface quality of impeller processing. At the same time, the use of automatic clamping fixtures achieves precise clamping and efficient flow guidance of the impeller. It can be combined with automated clamping action to greatly improve clamping efficiency and processing safety, and is particularly suitable for abrasive finishing of precision workpieces such as small aerospace impellers. Attached Figure Description

[0013] Figure 1 A schematic diagram of the overall structure of a device for ultra-precision machining of aerospace impellers using abrasive flow.

[0014] Figure 2 Schematic diagram of bearing mounting base structure

[0015] Figure 3 Schematic diagram of the constant temperature control device

[0016] Figure 4 Schematic diagram of the rotary stirring device

[0017] Figure 5 Schematic diagram of the fixture section

[0018] Figure 6 Schematic diagram of the connecting part Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings. It should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concept of the invention. Other embodiments obtained by those skilled in the art without inventive effort are all within the protection scope of this invention.

[0020] This invention provides a technical solution: an equipment for ultra-precision machining of aerospace impellers using abrasive flow comprises a lifting and rotating device, a clamping device, a connecting device, a stirring device, a temperature control device, and an auxiliary worktable. Because this invention is a composite structure, it is installed from top to bottom. The auxiliary part of the workbench of the device consists of a workbench (29), a material box (26), a plugging hole (32), and fixing bolts. First, align the opening above the material box (26) with the through hole of the workbench (29), and then fix the material box (26) on the workbench (29), thereby completing the installation of the auxiliary part of the workbench of the device.

[0021] The lifting and rotating device consists of a lifting cylinder (1), a cylinder telescopic rod (2), a pad (3), a connecting plate (4), an angular contact ball bearing mounting seat one (5), an angular contact ball bearing one (501), a transmission shaft (6), an angular contact ball bearing mounting seat two (14), an angular contact ball bearing two (1401), an auxiliary tripod (9), a bushing (8), a pulley one (7), a pulley two (11), a belt (10), a small reducer (12), a small reducer mounting seat (13), screws, and bolts. First, the lifting cylinder (1) is bolted to the workbench (29). The threaded hole at the bottom of the pad (3) is threaded to the extension rod (2) of the lifting cylinder. Then, the pad (3) is bolted to the connecting plate (4). The angular contact ball bearing mounting seat (5) is bolted to the other end of the connecting plate (4). The angular contact ball bearing (501) is mounted on the angular contact ball bearing mounting seat (5). Then, the top of the transmission shaft (6) has a cylindrical shaft (601) which is connected to the angular contact ball bearing (501) through clearance fit. The pulley (7) is keyed onto the bushing (8). The belt (10) is installed onto the pulley (7). The inside of the bushing (8) is connected to the transmission shaft. The splined shaft (602) of the moving shaft is fitted, and the bottom cylindrical part of the bushing (8) is connected to the second angular contact ball bearing (1401) through clearance fit. The second angular contact ball bearing mounting seat (14) is fixed on the auxiliary triangular platform (9) with screws. The auxiliary triangular platform (9) is installed on the worktable (29) with bolts. The second pulley (11) is connected to the first pulley (7) through the belt (10). The second pulley (11) is installed on the output shaft of the small reducer (12) through a key. The small reducer (12) is installed on the small reducer mounting bracket (13) through clearance fit. The small reducer mounting bracket (13) is installed on the worktable (29) with bolts.

[0022] The connecting part consists of a coupling (15) and fixing bolts. The coupling (15) consists of an upper sleeve (1501), a nut, a bolt sleeve, a bolt, a diaphragm, and a lower sleeve (1502). First, the upper sleeve of the coupling (15) is fixed to the threaded hole on the spline drive shaft with fixing bolts. Then, the lower sleeve of the coupling is connected to the threaded hole on the driven shaft of the clamp part with fixing bolts, thereby realizing the installation of the connecting part of the equipment.

[0023] The clamping part consists of a driven shaft (16), a jaw connecting seat (31), a jaw (30), an impeller (17), a spring (3001), bolts, nuts, and a key. First, the impeller (17) and the jaw (30) are positioned. The jaw (30) is first connected to the jaw connecting seat (31) by bolts and pre-tightened by spring (3001) to clamp the impeller (17). After determining the position, the bolts are pre-tightened to fix the impeller (17), thereby completing the top connection work of the clamping part of the equipment.

[0024] The stirring device consists of a spiral stirring paddle (20), a stirring column (2001), a deep groove ball bearing mounting seat one (2002), a deep groove ball bearing one (2003), a deep groove ball bearing mounting seat two (2004), a deep groove ball bearing two (2005), a large pulley (19), a small pulley (23), a V-belt (24), a motor (22), a key, and screws. First, the stirring column (2001) is fixed to the central shaft of the spiral stirring paddle (20) with screws. The deep groove ball bearing mounting seat one (2002) is fixed to the inner wall of the material box (26) with screws. The deep groove ball bearing one (2003) is installed on the deep groove ball bearing mounting seat one (2002) with a clearance fit. The central shaft of the spiral stirring paddle (20) is then... The inner ring of the second deep groove ball bearing (2005) is installed with clearance fit. The second deep groove ball bearing mounting seat (2004) is fixed to the material box (26) with bolts. The second deep groove ball bearing (2005) is installed on the second deep groove ball bearing mounting seat (2004) with clearance fit. Then, the spiral stirring device is installed inside the material box (26). The large pulley (19) is installed on the central shaft of the spiral stirring paddle (20) with a key. The small pulley (23) is installed on the output shaft of the motor (22) with a key. The motor (22) is fixed to the worktable (29) with bolts. The large pulley (19) and the small pulley (23) are connected together with a V-belt (24). Thus, the installation of the stirring device of the equipment is realized.

[0025] The constant temperature control device consists of a water tank (21), a water pump (18), inlet pipe 1 (2101), inlet pipe 2 (2102), inlet pipe 3 (2103), return pipe (25), temperature sensor (2801), temperature controller (28), AC contactor (27), and water pipe interface. First, the water tank (21) is fixed to the bottom of the workbench (29) with bolts. The water pipe interface is then connected to the outlet of the water tank via a threaded connection. Inlet pipe 1 (2101) is connected to the water pipe interface and the inlet (1801) of the water pump. Inlet pipe 2 (2102) is then connected via a threaded connection. At the outlet (1802) of the water pump, the second inlet pipe (2102) is connected to the water pipe loop inside the material box (26), and the return pipe (25) is connected back to the bottom of the water tank (21) through a threaded connection. The temperature sensor (2801) is installed inside the material box (26) at half the height to monitor the abrasive temperature in real time. The temperature sensor (2801) is connected to the temperature controller (28) through three leads. The temperature controller (28) is connected to the AC contactor (27) through leads. The AC contactor (27) is connected to the water pump (18) through a wire. Thus, the installation of the temperature control part of the equipment is completed.

[0026] In operation, the impeller (17) is first installed onto the clamp (30) of the fixture, then the abrasive is injected into the hopper (26), and then the motor (22) is powered to drive the stirring mechanism (20) to rotate, thereby preventing the abrasive from settling. Then the cylinder (1) is started to work, and the upper and lower depths are adjusted to completely immerse the impeller (17) in the abrasive. Finally, the small reducer (12) is powered on, and the impeller (17) is rotated by the pulley drive, and the abrasive flow precision machining of the impeller (17) begins. During the operation, the temperature sensor (2801) monitors the temperature of the abrasive in real time and transmits it to the temperature controller (28). (28) The temperature signal is processed and displayed. When the abrasive temperature reaches the preset upper limit, the relay output contact of the temperature controller (28) closes and outputs a control signal to the coil of the AC contactor (27). When the temperature drops to the preset lower limit, the output contact opens and cuts off the control signal. The coil of the AC contactor (27) is switched on and off according to the output signal of the temperature controller (28), thereby controlling the opening and closing of its main contacts to realize the on and off control of the power supply circuit of the water pump (18). The water pump (18) is directly powered by the main contacts of the AC contactor (27) and completes the cooling cycle of the abrasive under the automatic control of the temperature controller (28) to maintain the abrasive temperature stability.

[0027] Although embodiments of the invention have been shown and described, those skilled in the art will recognize that changes, modifications, substitutions, and variations can be made to the implementations without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A device for ultra-precision machining of aerospace impellers using abrasive flow, characterized in that, The equipment consists of a lifting and rotating device, a clamping device, a connecting device, a stirring device, a constant temperature control device, and an auxiliary worktable. The lifting and rotating device comprises a lifting cylinder, pads, a connecting plate, angular contact ball bearing mounting seats one and two, angular contact ball bearings one and two, an auxiliary triangular platform, a bushing, a drive shaft, pulley one and two, a belt, a small reducer, a small reducer mounting platform, screws, and bolts. The clamping device comprises a driven shaft, a gripper connecting seat, grippers, springs, bolts, and nuts. The constant temperature control device comprises a temperature sensor, a temperature controller, an AC contactor, a water pump, and cooling pipes. The auxiliary worktable consists of a worktable, a... The system comprises a material bin and bolts. The auxiliary triangular platform has a through hole and is connected to the worktable via bolts. The bottom of the lifting cylinder has a through hole and is connected to the worktable via bolts. The bottom of the pad has a threaded hole and is connected to the telescopic rod of the lifting cylinder via threads. The top two sides of the pad have countersunk holes and are connected to a connecting plate via screws. The connecting plate has a round hole that mates with an angular contact ball bearing mounting seat. The angular contact ball bearing mounting seat has countersunk holes around its mounting hole and is connected to the threaded hole on the connecting plate via screws. The angular contact ball bearing mounting seat has a mounting hole and is connected to the angular contact ball bearing via a clearance fit. The cylindrical shaft on the drive shaft is connected to the angular contact ball bearing via a clearance fit. The bushing has a spline groove and... The drive shaft is fitted with a splined shaft. The first pulley has a keyway and is connected to the shaft sleeve via a key. The second angular contact ball bearing is connected to the shaft sleeve via a clearance fit. The second angular contact ball bearing mounting seat has a mounting hole and is connected to the second angular contact ball bearing via a clearance fit. The auxiliary triangular platform has a round hole that mates with the second angular contact ball bearing mounting seat. The mounting hole of the second angular contact ball bearing mounting seat has countersunk holes around it and is connected to the threaded holes on the auxiliary triangular platform via screws. The miniature reducer is mounted in the mounting hole of the miniature reducer mounting bracket via a clearance fit. The bottom of the miniature reducer mounting bracket has a through hole and is connected to the worktable via bolts. The second pulley has a keyway and is connected to the output shaft of the miniature reducer via a key. The first and second pulleys are connected by a belt to realize the transmission between the output shaft and the drive shaft of the small reducer. The clamping jaw connecting seat is fixedly connected to the lower end of the drive shaft. The clamping jaw connecting seat is connected and fixed to the clamping jaw by bolts and a preload is added by a spring to clamp the impeller, thus completing the installation of this part. The temperature sensor probe extends into the abrasive box, and its lead wire is connected to the signal input terminal of the temperature controller through a shielded cable. The output terminal of the temperature controller relay is connected in series with the coil circuit of the AC contactor. The main contacts of the AC contactor are connected in series with the power supply circuit of the water pump. The water pump is connected to the cooling pipe, which is laid on the side wall or inside the abrasive box, thereby realizing real-time monitoring and automatic constant temperature control of the abrasive temperature.

2. The equipment for abrasive finishing of an impeller according to claim 1, characterized in that: The drive shaft and the inner ring of the first angular contact ball bearing are fitted with a clearance fit, the outer ring of the first angular contact ball bearing and the first bearing mounting seat are fitted with a clearance fit, the drive shaft and the inner ring of the second angular contact ball bearing are fitted with a clearance fit, the outer ring of the second angular contact ball bearing and the second bearing mounting seat are fitted with a clearance fit, and the first pulley is axially positioned by a shaft shoulder and a locking nut.

3. The equipment for abrasive finishing of an impeller according to claim 1, characterized in that: The clamping connecting seat is fixedly connected to the lower end of the drive shaft, and the clamping cylinder is installed on the upper end of the drive shaft. The clamping drive arm is driven by the axial push rod to make the radial jaws clamp the impeller hub. The sealing guide ring fits the outer circle of the impeller, so that the abrasive is forced through the blade flow channel under the reciprocating extrusion action. Before processing, the clamp first clamps the impeller, and then the lifting cylinder drives the whole into the abrasive box. After processing, the lifting cylinder is reset, and the clamp can be released to unload the material.

4. The equipment for abrasive finishing of an impeller according to claim 1, characterized in that: The temperature sensor is a three-wire Pt100 platinum resistance thermometer. Its leads are connected to the RTD signal input terminal of the temperature controller via a shielded cable. The shielding layer is grounded only at one end on the control cabinet side. When the abrasive temperature reaches the preset upper limit, the output contact of the temperature controller closes, triggering the AC contactor coil to energize and start the water pump. Cooling circulating water is used to cool the abrasive box through the pipeline. When the temperature drops to the preset lower limit, the output contact of the temperature controller opens, and the water pump stops working.

5. The equipment for abrasive finishing of an impeller according to claim 1, characterized in that: The abrasive box is equipped with a stirring device, which consists of a stirring motor, a large pulley, a small pulley, a V-belt, a stirring claw connecting column, and stirring claws. The stirring motor has a through hole at the bottom and is fixed to the material cylinder mounting base with bolts. The small pulley is connected to the motor output shaft by a key, and the large pulley is connected to the stirring claw connecting column by a key. The V-belt connects the large pulley and the small pulley. The stirring claw connecting column is fixed to the stirring claws by threads, so as to achieve uniform stirring of the abrasive.

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