Tensioning type clamp for machining aero-engine blade

Abstract

The utility model discloses a tensioning type clamp for machining an aero-engine blade, relates to the technical field of aero-engine blade machining, enables clamping force to be changed into axial tension from traditional axial pressure, and solves the problem that a workpiece is bent by cutting force. The axial tension can reduce or eliminate the vibration problem of the workpiece in the longitudinal direction during cutting; according to the specific scheme, the tensioning type clamp for machining the aero-engine blade comprises a tensioning shaft and a three-jaw chuck which are used for fixing the two ends of a blade blank, the tensioning shaft is located in a clamp body, an end cover is arranged on one side of the clamp body, and a matching part used for being fixedly connected with a machine tool tailstock is arranged on the other side of the clamp body; the first end of the tensioning shaft penetrates through the end cover and is provided with a positioning hole, the peripheral side of the second end is provided with a fixing piece, a sealing ring is arranged between the tensioning shaft and the end cover, the peripheral side of the tensioning shaft is sequentially sleeved with a spring and a bearing from the end cover to the fixing piece, and the side face of the first end of the tensioning shaft is provided with a first threaded hole used for fixing a blade blank.

Description

Technical Field

[0001] The utility model relates to the technical field of aircraft engine blade processing, in particular to a tensioning clamp used for processing aircraft engine blades. Background Art

[0002] Aircraft engine blades are important components of the engine. The design and manufacturing level of the blades have a significant impact on the comprehensive performance and service life of the aircraft engine. In order to meet the requirements of the engine's safety, reliability, and motion accuracy during operation, the blades must achieve the corresponding accuracy in size and shape, and have good surface integrity. Aircraft engine blades are typical thin-walled components. During their processing, they are sensitive to factors such as cutting force, thermal load, and coolant medium. Blades are prone to vibration during processing, resulting in bending deformation and residual stress after processing, affecting the processing accuracy of the blades. Ultimately, it is difficult to obtain high shape and size accuracy and small surface roughness of the blades.

[0003] The reason why the above-mentioned technical problems exist in blade processing is closely related to the fixture used. The existing method of clamping aeroengine blades is to clamp one end of the blade with a chuck and support the other end with a center support using the tailstock of the machine tool. During processing, the workpiece is subjected to clamping force, cutting force and centrifugal force, which cause blade vibration. In addition, cutting heat will also cause thermal expansion, which are important reasons for the bending and deformation of the blade and the existence of residual stress inside, which ultimately affects the processing accuracy of the blade. Utility Model Content

[0004] In view of the deficiencies in the prior art, the purpose of the utility model is to provide a tensioning clamp for processing aircraft engine blades, so that the clamping force is changed from axial pressure to axial tension, thereby solving the problem of the cutting force bending the workpiece, and the axial tension can reduce or eliminate the longitudinal vibration of the workpiece during cutting, so that the cutting process can be carried out smoothly, reducing the bending deformation and residual stress of the blade after processing, and effectively improving the processing accuracy of the blade.

[0005] In order to achieve the above purpose, the utility model is implemented through the following technical solutions:

[0006] A tensioning fixture for machining aircraft engine blades, comprising a tensioning shaft and a three-jaw chuck for fixing both ends of a blade blank, wherein the tensioning shaft is located inside a clamp body, an end cover is arranged on one side of the clamp body, and a matching portion for fixed connection with a tailstock of a machine tool is arranged on the other side;

[0007] The first end of the tensioning shaft passes through the end cover and is provided with a positioning hole, a fixing piece is provided on the circumferential side of the second end, a sealing ring is provided between the tensioning shaft and the end cover, a spring and a bearing are sequentially sleeved on the circumferential side of the tensioning shaft from the end cover to the fixing piece, and a first threaded hole is provided on the side surface of the first end of the tensioning shaft for fixing the blade blank.

[0008] As a further implementation, a tapered shank structure is provided on one side of the mating portion for mating with a Morse taper hole of a tailstock of a machine tool.

[0009] As a further implementation, the matching portion is a circular plate structure, which is used to match with the side of the tailstock of the machine tool, and the matching portion is evenly provided with a plurality of second threaded holes along the circumferential direction thereof.

[0010] As a further implementation, the outer diameter of the fixing member is matched with the outer diameter of the bearing inner ring.

[0011] As a further implementation, a pressure sensor is arranged between the spring and the bearing, and the pressure sensor is sleeved on the circumference of the tensioning shaft. One end of the spring abuts against the end cover, and the other end abuts against the pressure sensor.

[0012] As a further implementation, the outer diameter of the spring and the outer diameter of the pressure sensor are matched with the outer diameter of the inner ring of the bearing.

[0013] As a further implementation, the clamp body is hollow inside, and the clamp body is fixedly connected to the end cover by bolts.

[0014] As a further implementation, the first threaded hole of the tensioning shaft is connected to the positioning hole, and the tensioning shaft fixes the blade blank by means of a set screw cooperating with the first threaded hole.

[0015] As a further implementation, a thread is provided on the circumference of the second end of the tensioning shaft, and the fixing member is a locking nut.

[0016] As a further implementation method, the tensioning shaft, the clamp body, and the three-jaw chuck are located on the same axis.

[0017] The beneficial effects of the above utility model are as follows:

[0018] 1. The utility model realizes that the clamping force is changed from the traditional axial pressure to the axial tension by setting the tension shaft, the clamp body, the spring and other structures, which solves the problem of the workpiece being bent by the cutting force, and the axial tension can reduce or eliminate the problem of the longitudinal vibration of the workpiece during cutting, so that the cutting process can be carried out smoothly, reduce the bending deformation and residual stress of the blade after processing, and improve the processing accuracy of the blade. The fixture has a simple structure, is easy to manufacture, has a low cost, and is very convenient to install and operate.

[0019] 2. A pressure sensor is arranged between the spring and the bearing of the utility model, and the pressure sensor is sleeved on the circumference of the tensioning shaft. Through the arrangement of the pressure sensor, quantitative control of the tensioning force can be effectively achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention.

[0021] Figure 1 The utility model is a schematic diagram of the overall structure of a tensioning fixture for processing aircraft engine blades in an embodiment of the utility model.

[0022] In the figure: the distances or sizes between parts are exaggerated to show the positions of various parts, and the schematic diagram is for reference only.

[0023] Among them: 1. three-jaw chuck; 2. blade blank; 3. tensioning shaft; 4. sealing ring; 5. bolt; 6. clamp base; 7. bolt; 8. machine tool tailstock; 9. locking nut; 10. bearing; 11. pressure sensor; 12. spring; 13. adjusting gasket; 14. end cover; 15. set screw; 16. round nut. DETAILED DESCRIPTION

[0024] It should be noted that the following detailed descriptions are all illustrative and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0025] Embodiment 1

[0026] In a typical implementation of the present invention, reference is made to Figure 1 As shown, a tensioning fixture for processing aircraft engine blades includes a three-jaw chuck 1 and a clamp body 6. The clamp body 6 is provided with a tensioning shaft 3. The three-jaw chuck 1 is used to clamp the first end of the blade blank 2, and the tensioning shaft 3 is used to tighten the blade blank 2. The three-jaw chuck 1 is a spindle assembly of a machine tool.

[0027] like Figure 1 As shown, the tensioning shaft 3 is arranged horizontally, and is located in the horizontally arranged clamp body 6. The clamp body 6 is hollow inside, and an end cover 14 is arranged on the side of the clamp body 6 close to the three-jaw chuck 1. The end cover 14 is a circular end cover, and an annular adjustment gasket 13 is arranged between the end cover and the clamp body. A matching part for fixed connection with the tailstock 8 of the machine tool is arranged on the other side of the clamp body 6.

[0028] Specifically, Figure 1Taking the direction of the figure in as an example, the left end of the tensioning shaft 3 passes through the center of the end cover 14, the right end of the tensioning shaft 3 is located in the clamp body, and a sealing ring 4 is arranged between the tensioning shaft and the end cover, and the sealing ring 4 is located at the center inner hole of the end cover 14. The clamp body 6 and the end cover 14 are fixedly connected by six bolts 5, and the six bolts are evenly distributed along the edge of the end cover in a circumference, effectively fixing the end cover and the clamp body.

[0029] Furthermore, the right end of the tensioning shaft 3 is located in the clamp body, and the right end of the tensioning shaft 3 is provided with an external thread, which cooperates with two locking nuts 9. On the circumferential side of the tensioning shaft 3, a spring 12, a pressure sensor 11, and a bearing 10 are sequentially sleeved from the end cover 14 to the locking nut 9. The spring 12, the pressure sensor 11, and the bearing 10 are sequentially abutted against the locking nut.

[0030] The clamping body 6 is arranged horizontally and is located on the same axis as the three-jaw chuck 1 and the tensioning shaft 3. The matching part is arranged on the right side of the clamping body 6 and is an integrated structure with the clamping body. The matching part includes a circular cover plate. A tapered shank structure is arranged on the right side of the circular cover plate. The specific shape of the tapered shank structure is a truncated cone, which is adapted to the shape of the Morse taper hole of the machine tool tailstock 8. The machine tool tailstock is arranged on the right side of the matching part in actual work. Six threaded holes evenly distributed in a circle are arranged on the edge of the circular cover plate, and threaded holes are correspondingly arranged on the side of the machine tool tailstock. The tapered shank part is inserted into the Morse taper hole, and the clamping body and the machine tool tailstock are fixed by the cooperation of the bolt 7 and the threaded hole.

[0031] like Figure 1 As shown, a positioning hole is provided at the left end of the tensioning shaft 3 for matching the blade blank, and a threaded hole is provided on the side, which is connected to the positioning hole. When positioning and clamping the blade blank 2, the left end of the blade blank 2 is first clamped by the three-jaw chuck 1, and then according to the size of the blade blank 2, the position of the machine tailstock and the tensioning shaft is adjusted by turning the handwheel of the machine tailstock 8 or by the automatic control system to complete the matching of the positioning hole of the right end of the blade blank 2 with the tensioning shaft 3, and then the threaded hole is matched with a set screw, and the set screw is tightened to achieve clamping and fixing of the blade blank. A round nut 16 or a gasket can be set between the set screw 15 and the tensioning shaft to achieve further fixation.

[0032] In order to facilitate the fixation of the blade blank 2, a cylindrical structure is processed at both ends of the blade blank 2 for positioning and clamping the blade blank.

[0033] After the three-jaw chuck and the tensioning shaft have fixedly clamped both ends of the blade blank, by turning the machine tool tailstock handwheel or retreating the tailstock sleeve through the automatic control device, an axial pulling force can be applied to the blade blank to achieve reliable clamping of the workpiece.

[0034] It can be understood that the outer diameter of the locking nut 9 is matched with the outer diameter of the inner ring of the bearing 10, the locking nut 9 does not contact the outer ring of the bearing, the outer diameter of the spring 12 and the outer diameter of the pressure sensor 11 are matched with the outer diameter of the inner ring of the bearing, and the outer edge of the pressure sensor 11 does not contact the outer ring of the bearing. When the pressure sensor 11 contacts the inner ring of the bearing, a radial ball rolling bearing or a thrust ball bearing can be selected to achieve effective application of the axial force of the clamp system.

[0035] In other examples, when the pressure sensor 11 contacts the outer ring of the bearing, a thrust bearing can be selected to achieve effective application of the axial force of the clamping system, and the bearing will not be easily damaged.

[0036] In this embodiment, a sealing ring 4 is provided between the tensioning shaft 3 and the end cover 14, which is a rotary seal. The rotary seal is a form of dynamic seal and is used to seal rods, shafts, pins, rotary joints, etc. that have rotating or swinging motions. It is a prior art.

[0037] The specific working principle is as follows:

[0038] like Figure 1 As shown, when the clamp is used, first use the three-jaw chuck 1 to position and clamp the cylinder on one side of the workpiece, then adjust the position of the tensioning device and the machine tailstock 8 according to the size of the blade blank 2, place the cylinder on the other side of the workpiece in the positioning hole of the tensioning shaft 3 of the tensioning device, and tighten the set screw on the tensioning shaft to fix the workpiece. Turn the hand wheel of the machine tailstock or use the automatic control device to make the tailstock sleeve retreat. During this process, the clamp body moves to the right, pushing the spring 12 through the end cover 14, and the spring 12 is compressed, squeezing the pressure sensor 11. The pressure sensor 11 and the set nut 9 press the bearing. By applying an axial tension to the blade blank 2, the workpiece is reliably clamped.

[0039] The tensioning force applied to the tensioning shaft 3 (ie, the amount of compression of the spring 12 ) is quantitatively controlled by the force sensor 11 , thereby finally achieving the tensioning of the blade blank 2 .

[0040] This embodiment realizes the tension clamping of one end of the blade blank 2, so that the clamping force is changed from the traditional axial pressure to the axial tension, which solves the problem of the workpiece being bent by the cutting force, and the axial tension can reduce or eliminate the problem of the longitudinal vibration of the workpiece during cutting, so that the cutting process can be carried out smoothly, reduce the bending deformation and residual stress of the blade after processing, and improve the processing accuracy of the blade. The fixture has a simple structure, is easy to manufacture, has a low cost, and is very convenient to install and operate.

[0041] The above description is only the preferred embodiment of the utility model, and is not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A tensioning fixture for machining aircraft engine blades, characterized in that: It includes a tensioning shaft and a three-jaw chuck for fixing both ends of the blade blank. The tensioning shaft is located inside the clamp body. An end cover is arranged on one side of the clamp body, and a matching part for fixed connection with the tailstock of the machine tool is arranged on the other side. The clamp body is arranged horizontally and is located on the same axis as the three-jaw chuck and the tensioning shaft. The first end of the tensioning shaft passes through the end cover and is provided with a positioning hole, a fixing piece is provided on the circumferential side of the second end, a sealing ring is provided between the tensioning shaft and the end cover, a spring and a bearing are sequentially sleeved on the circumferential side of the tensioning shaft from the end cover to the fixing piece, and a first threaded hole is provided on the side surface of the first end of the tensioning shaft for fixing the blade blank.

2. A tensioning fixture for machining aircraft engine blades according to claim 1, characterized in that: A tapered shank structure is provided on one side of the matching portion for matching with the Morse tapered hole of the tailstock of the machine tool.

3. A tensioning fixture for machining aircraft engine blades according to claim 2, characterized in that: The matching portion is a circular plate structure, which is used to match with the side surface of the tailstock of the machine tool. The matching portion is evenly provided with a plurality of second threaded holes along the circumferential direction thereof.

4. The tensioning fixture for machining aircraft engine blades according to claim 1, characterized in that: The outer diameter of the fixing member is matched with the outer diameter of the bearing inner ring.

5. The tensioning fixture for machining aircraft engine blades according to claim 1, characterized in that: The clamp body is hollow inside, and the clamp body is fixedly connected with the end cover by bolts.

6. The tensioning fixture for machining aircraft engine blades according to claim 1, characterized in that: The first threaded hole of the tensioning shaft is connected to the positioning hole, and the tensioning shaft fixes the blade blank by means of a set screw cooperating with the first threaded hole.

7. The tensioning fixture for machining aircraft engine blades according to claim 1, characterized in that: A thread is arranged on the circumferential side of the second end of the tensioning shaft, and the fixing member is a locking nut.

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