Tenon supporting device for blade tip grinding of aero-engine high-pressure turbine blade

Abstract

The invention discloses an aero-engine high-pressure turbine blade tip grinding tenon tensioning device which comprises a front wedge-shaped ejector block, a trapezoidal ejector block, a rear wedge-shaped ejector block and a compression nut which are sequentially arranged in the middle of a screw from front to back. Pressure providing mechanisms are arranged between the front wedge-shaped ejector block and the screw head of the screw and between the rear wedge-shaped ejector block and the pressing nut. When the front wedge-shaped ejector block and the rear wedge-shaped ejector block extrude towards the middle at the same time, the trapezoid ejector block can be jacked upwards. The problems that in the existing tool manufacturing process, errors are generated, fit clearances are not uniform due to blade differences, and the defects of large outer diameter runout, size out-of-tolerance and the like are generated after the blades are ground due to the fact that the blades are too large in blade lifting in the grinding process are solved.

Description

Technical Field

[0001] The invention relates to the field of devices for grinding blades of aircraft engines, in particular to a device for tightening a blade tip grinding tenon of a high-pressure turbine blade of an aircraft engine. Background Art

[0002] High-pressure turbine blades are key components of aircraft engine power energy devices. Any damage will have a serious impact on the flight safety of military and civil aviation. Under the harsh working environment of high-speed aerodynamic loads, centrifugal loads, vibration loads and high-temperature gas erosion, the blades will have a large number of cracks and wear defects at the blade tips after service, reducing the engine thrust. During the use of aircraft engines, the blades are core components and are easily worn out, requiring repair or replacement. Almost every engine of a certain type needs to be replaced during maintenance. When replacing, the new high-vortex blades need to be ground one by one according to the size of the casing. Before grinding, the high-vortex blades need to be assembled on the original plate, which is a bottleneck in the repair process of this type of engine. The blades are made of precision casting, the process is complex, the pass rate is low, and the output is limited.

[0003] During the manufacturing process of high-vortex blades, the size of each high-pressure turbine disk will change after flight use, which will cause a gap in the fit clearance between the blades and the inner wall of the casing. In addition, after service, the blades have different states of wear and damage. When reconfiguring new blades during engine repair, it is easy to cause inconsistent fit clearances and excessive runout due to the complex shapes of the blade tenons and high-vortex disk grooves and the existence of shape tolerances, and the uncertain outer diameter size of the blades. Ordinary grinding methods cannot simulate the state of the blades being thrown out during work, and the grinding effect is poor, resulting in unstable outer diameter dimensions during the grinding process, and defects such as large outer diameter runout and dimensional tolerances. Summary of the invention

[0004] The purpose of the present invention is to provide a tenon tightening device for grinding the tip of a high-pressure turbine blade of an aircraft engine, so as to solve the problems of errors in the existing tooling manufacturing process, uneven fitting clearance caused by blade differences, and large outer diameter runout and dimensional out-of-tolerance caused by excessive blade thickness during the grinding process.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions: A blade tip grinding tenon support device for a high-pressure turbine blade of an aircraft engine comprises a front wedge-shaped top block, a trapezoidal top block, a rear wedge-shaped top block and a clamping nut which are arranged in sequence from front to back in the middle of a screw. A pressure providing mechanism is arranged between the front wedge-shaped top block and the screw head of the screw, and between the rear wedge-shaped top block and the clamping nut. When the front wedge-shaped top block and the rear wedge-shaped top block are squeezed toward the middle at the same time, the trapezoidal top block can be lifted upward.

[0006] During the grinding of the outer diameter of the blade tip, the tenon tightening device is used to maintain sufficient tightening force on the blade tenon to push the blade out, simulating the working state of the blade, that is, simulating the high-pressure turbine blade to be thrown outward under the action of centrifugal force when rotating at high speed, and reaching the state of maximum outer diameter, thereby avoiding the error caused by the gap between the blade tenon and the high scroll disk and the tool letting down during the grinding process, and obtaining the expected outer diameter size of the repair; The specific usage mechanism is to assemble the front wedge-shaped top block, the trapezoidal top block, the rear wedge-shaped top block and the clamping nut on the screw in sequence, and then insert the assembled aircraft engine high-pressure turbine blade tip grinding tenon tightening device into the tenon of the high-pressure turbine disc, and the pressure providing mechanism continuously applies pressure to the front wedge-shaped top block and the rear wedge-shaped top block, and the trapezoidal top block is pushed upward by the front wedge-shaped top block and the rear wedge-shaped top block, and the top of the trapezoidal top block fits tightly with the bottom of the blade, so as to provide the blade with continuous pressure perpendicular to the axial direction of the blade disc, ensure the expansion force between the blade and the tenon, expand the maximum outer diameter of the entire blade, effectively eliminate the gap caused by the tooling manufacturing process and the blade difference, and effectively eliminate the vibration gap of the blade during high-speed grinding, enhance the stability of the process, improve the grinding quality of the high-pressure turbine blade, and improve the qualified rate in the blade grinding process.

[0007] The tenon tightening device adopts metric parts, has good applicability and integrity, low difficulty in assembly and debugging, high efficiency, and a simple structure that helps reduce the labor intensity of the operator. In addition, it can also match different models of high-vortex blades and high-vortex discs, and has a certain degree of versatility.

[0008] As a further preferred embodiment of the present invention, the pressure providing mechanism is a pressure spring.

[0009] The pressure providing mechanism has a simple structure. When working, the spring provides continuous elastic pressure, which can effectively eliminate the vibration gap generated by the blade during high-speed grinding and improve the grinding accuracy.

[0010] As a further preferred embodiment of the present invention, a front end surface of the front wedge-shaped top block and a rear end surface of the rear wedge-shaped top block are provided with spring grooves, and one end of the pressure spring is connected to the spring groove.

[0011] As a further preferred embodiment of the present invention, the front wedge-shaped top block, the rear wedge-shaped top block and the trapezoidal top block all match the shape of the tooling mortise and tenon.

[0012] The overall freedom of the tenon support device can be limited so that it can only slide in the direction of the tenon groove.

[0013] The method for tightening the tenon of a blade of a high-pressure turbine blade of an aircraft engine using the tenon tightening device for grinding the tip of the blade of any of the above-mentioned items comprises the following steps: A. installing a front wedge-shaped top block, a trapezoidal top block, a rear wedge-shaped top block and a clamping nut on the screw rod in sequence to form a tenon support; B. then pushing the tenon tightening device into the lower part of the tenon groove of the high-scroll disk, and then pushing the blade into the upper part of the tenon groove of the high-scroll disk; C. tightening the clamping nut, at which time the pressure providing mechanisms at both ends begin to provide an inward thrust, pushing the front wedge-shaped top block and the rear wedge-shaped top block to shrink inward. Since an upward force is generated after the wedge surface contacts the trapezoidal top block, a circular groove is left in the middle of the trapezoidal top block, which can move up and down within a certain range. Under the push of pressure, the trapezoidal top block moves upward until it fits with the bottom of the blade. The blade is subjected to the transmitted upward pressure, and the upper and lower gaps between the tenon groove and the blade are compressed, completing the tightening work.

[0014] This assembly method requires the installation of a whole plate of blades and tenon support devices, and finally the whole is placed on a lathe for turning. Since the pressure providing mechanism continuously provides pressure, the gaps in all force transmission directions in the tenon support device remain tightly fitted, and the blades can be continuously subjected to upward pressure in the blade direction, simulating the state of the blades being subjected to centrifugal force when working in the engine, and can resist the processing stress from the turning tool during lathe processing, offset the vibration gap during processing, and due to the continuous close fit, it can also improve the heat dissipation of the blades during turning, thereby improving the turning quality.

[0015] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects: 1. During the grinding of the outer diameter of the blade tip, the tenon support device is used to maintain sufficient support force on the blade tenon to push the blade out, simulating the state of the blade at work, that is, simulating the high-pressure turbine blade when it rotates at high speed. Under the action of centrifugal force, the blade is thrown outward to reach the state of the largest outer diameter, avoiding the error caused by the gap between the blade tenon and the high scroll disk, and the tool letting down during the grinding process, and obtaining the expected outer diameter size of the repair.

[0016] 2. The tenon tightening device adopts metric parts, which has good applicability and integrity, low difficulty in assembly and debugging, high efficiency, and simple structure, which is conducive to reducing the labor intensity of operators. In addition, it can also match different types of high-vortex blades and high-vortex discs, and has certain versatility.

[0017] 3. The front wedge-shaped top block, the rear wedge-shaped top block and the trapezoidal top block all match the shape of the tooling mortise and tenon, which can limit the overall freedom of the tenon support device and can only slide in the mortise and tenon direction.

[0018] 4. This assembly method requires the installation of a whole plate of blades and tenon support devices, and finally the whole is placed on a lathe for machining. Since the pressure providing mechanism continuously provides pressure, the gaps in all force transmission directions in the tenon support device remain tightly fitted, and the blades can be continuously subjected to upward pressure in the blade direction, simulating the state of the blades being subjected to centrifugal force when working in the engine, and can resist the machining stress from the turning tool during lathe machining, offset the vibration gap during machining, and due to the continuous close fit, the heat dissipation of the blades during machining can be improved, thereby improving the machining quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of the present invention.

[0020] Figure 2 It is an assembly schematic diagram of the present invention.

[0021] Figure 3 The working process of the present invention is shown in the following figure. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0023] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features of the embodiments may be combined with each other.

[0025] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0026] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the product of the invention is usually placed when in use, or the positions or positional relationships commonly understood by those skilled in the art, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0027] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. Specific embodiment 1: Figure 1 , Figure 2 , Figure 3 The invention shows a device for tightening the tip grinding tenon of a high-pressure turbine blade of an aircraft engine, comprising a front wedge-shaped top block 2, a trapezoidal top block 3, a rear wedge-shaped top block 4 and a clamping nut 5 which are arranged in sequence in the middle of a screw 1 from front to back. A pressure providing mechanism 6 is arranged between the front wedge-shaped top block 2 and the screw head of the screw 1, and between the rear wedge-shaped top block 4 and the clamping nut 5. When the front wedge-shaped top block 2 and the rear wedge-shaped top block 4 are squeezed toward the middle at the same time, the trapezoidal top block 3 can be lifted upward.

[0029] During the grinding of the outer diameter of the blade tip, the tenon tightening device is used to maintain sufficient tightening force on the blade tenon to push the blade out, simulating the working state of the blade, that is, simulating the high-pressure turbine blade to be thrown outward under the action of centrifugal force when rotating at high speed, and reaching the state of maximum outer diameter, thereby avoiding the error caused by the gap between the blade tenon and the high scroll disk and the tool letting down during the grinding process, and obtaining the expected outer diameter size of the repair; The specific usage mechanism is to assemble the front wedge-shaped top block, the trapezoidal top block, the rear wedge-shaped top block and the clamping nut on the screw in sequence, and then insert the assembled aircraft engine high-pressure turbine blade tip grinding tenon tightening device into the tenon of the high-pressure turbine disc, and the pressure providing mechanism continuously applies pressure to the front wedge-shaped top block and the rear wedge-shaped top block, and the trapezoidal top block is pushed upward by the front wedge-shaped top block and the rear wedge-shaped top block, and the top of the trapezoidal top block fits tightly with the bottom of the blade, so as to provide the blade with continuous pressure perpendicular to the axial direction of the blade disc, ensure the expansion force between the blade and the tenon, expand the maximum outer diameter of the entire blade, effectively eliminate the gap caused by the tooling manufacturing process and the blade difference, and effectively eliminate the vibration gap of the blade during high-speed grinding, enhance the stability of the process, improve the grinding quality of the high-pressure turbine blade, and improve the qualified rate in the blade grinding process.

[0030] The tenon tightening device adopts metric parts, has good applicability and integrity, low difficulty in assembly and debugging, high efficiency, and a simple structure that helps reduce the labor intensity of the operator. In addition, it can also match different models of high-vortex blades and high-vortex discs, and has a certain degree of versatility. Specific embodiment 2: This embodiment further illustrates the pressure providing mechanism 6 based on the specific embodiment 1. The pressure providing mechanism 6 is a pressure spring.

[0032] The pressure providing mechanism has a simple structure. When working, the spring provides continuous elastic pressure, which can effectively eliminate the vibration gap generated by the blade during high-speed grinding and improve the grinding accuracy. Specific embodiment 3: This embodiment further illustrates the front wedge-shaped top block 2 based on the specific embodiment 2. The front end face of the front wedge-shaped top block 2 and the rear end face of the rear wedge-shaped top block 4 are provided with spring grooves, and one end of the pressure spring 6 is connected to the spring groove. Specific embodiment 4: This embodiment further illustrates the front wedge-shaped top block 2, the rear wedge-shaped top block 4 and the trapezoidal top block 3 on the basis of the specific embodiment 1, wherein the front wedge-shaped top block 2, the rear wedge-shaped top block 4 and the trapezoidal top block 3 all match the shape of the tooling mortise and tenon.

[0035] The overall freedom of the tenon support device can be limited so that it can only slide in the direction of the tenon groove. Specific embodiment 5: The method for tightening the tenon of a blade of a high-pressure turbine blade tip grinding of an aircraft engine described in any one of the above items comprises the following steps: A. installing a front wedge-shaped top block 2, a trapezoidal top block 3, a rear wedge-shaped top block 4 and a clamping nut 5 on a screw rod 1 in sequence to form a tenon support; B. then pushing the tenon clamping device into the lower part of the tenon groove of the high-volume disk, and then pushing the blade into the upper part of the tenon groove of the high-volume disk; C. tightening the clamping nut 5, at which time the pressure providing mechanism 6 at both ends begins to provide an inward thrust, pushing the front wedge-shaped top block 2 and the rear wedge-shaped top block 4 to shrink inward, because the wedge surface generates an upward force after contacting the trapezoidal top block 3, and a circular groove is left in the middle of the trapezoidal top block 3, which can move up and down within a certain range. Under the push of pressure, the trapezoidal top block 3 moves upward until it fits with the bottom of the blade, and the blade is subjected to the transmitted upward pressure, and the upper and lower gaps between the tenon groove and the blade are compressed, completing the tightening work.

[0037] This assembly method requires the installation of a whole plate of blades and tenon support devices, and finally the whole is placed on a lathe for turning. Since the pressure providing mechanism continuously provides pressure, the gaps in all force transmission directions in the tenon support device remain tightly fitted, and the blades can be continuously subjected to upward pressure in the blade direction, simulating the state of the blades being subjected to centrifugal force when working in the engine, and can resist the processing stress from the turning tool during lathe processing, offset the vibration gap during processing, and due to the continuous close fit, it can also improve the heat dissipation of the blades during turning, thereby improving the turning quality.

[0038] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A device for tightening the blade tip grinding tenon of an aircraft engine high-pressure turbine blade, characterized in that: The invention comprises a front wedge-shaped top block (2), a trapezoidal top block (3), a rear wedge-shaped top block (4) and a clamping nut (5) which are arranged in sequence from front to back in the middle of a screw rod (1). A pressure providing mechanism (6) is arranged between the front wedge-shaped top block (2) and the screw head of the screw rod (1), and between the rear wedge-shaped top block (4) and the clamping nut (5). When the front wedge-shaped top block (2) and the rear wedge-shaped top block (4) are pressed toward the middle at the same time, the trapezoidal top block (3) can be lifted upward.

2. The aero-engine high-pressure turbine blade tip grinding tenon bracing device according to claim 1, characterized in that: The pressure providing mechanism (6) is a pressure spring.

3. The aero-engine high-pressure turbine blade tip grinding tenon bracing device according to claim 2, characterized in that: The front end surface of the front wedge-shaped top block (2) and the rear end surface of the rear wedge-shaped top block (4) are provided with spring grooves, and one end of the pressure spring (6) is connected to the spring groove.

4. The aero-engine high-pressure turbine blade tip grinding tenon bracing device according to claim 1, characterized in that: The front wedge-shaped top block (2), the rear wedge-shaped top block (4) and the trapezoidal top block (3) all match the shape of the tooling tenon groove.

5. A method for tightening a blade tenon by using the blade tip grinding tenon tightening device of an aircraft engine high-pressure turbine blade as claimed in any one of claims 1 to 4, comprising the following steps: A. sequentially installing a front wedge-shaped top block (2), a trapezoidal top block (3), a rear wedge-shaped top block (4) and a clamping nut (5) on a screw rod (1) to form a tenon support; B. then pushing the tenon tightening device into the lower part of the tenon groove of the high scroll disk, and then pushing the blade into the upper part of the tenon groove of the high scroll disk; C. tightening the clamping nut (5), At this time, the pressure providing mechanisms (6) at both ends begin to provide an inward thrust, pushing the front wedge-shaped top block (2) and the rear wedge-shaped top block (4) to retract inward. As the wedge-shaped surface contacts the trapezoidal top block (3), an upward force is generated. A circular groove is left in the middle of the trapezoidal top block (3), which can move up and down within a certain range. Under the push of pressure, the trapezoidal top block (3) moves upward until it fits with the bottom of the blade. The blade is subjected to the transmitted upward pressure, and the upper and lower gaps between the blade and the tenon groove are compressed, completing the tightening work.

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