JP3932902B2 - Anti-rotation device for rear side seal member in hydraulic seal of biaxial aircraft engine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a non-rotating device for a hydraulic seal that seals between a high speed shaft and a low speed shaft of a biaxial aircraft engine having a high speed shaft and a low speed shaft.
[0002]
[Prior art]
A high bypass ratio turbofan engine used as an aircraft engine includes a large fan 1 for taking in air, a low-pressure compressor 2 and a high-pressure compressor 3 for compressing the taken-in air, as schematically shown in FIG. A combustor 4 that injects fuel into compressed air and burns, a high-pressure turbine 7 that is rotationally driven by combustion gas and transmits the rotational force to the high-pressure compressor 3 via an outer high-speed shaft 5, An engine body 9 having a low-pressure turbine 8 that is driven to rotate by combustion gas and transmits the rotational force to the low-pressure compressor 2 and the fan 1 via the inner low-speed shaft 6, and around the engine body 9 The nacelle 11 is provided through the strut 10 so that the intake air is bypassed, and the air is guided into the nacelle 11 by the rotation of the fan 1. To bypass ratio (engine bypass flow rate / engine body flow) increased to are to perform the operation. O represents the axial center of the engine body.
[0003]
When the accessory gear box 12 for driving an auxiliary machine such as a hydraulic pump is mounted in the nacelle 11, the radial drive shaft 13 is guided from the position in the engine body 9 into the nacelle 11 through the strut 10, The bevel gear 14 provided at the inner end portion of the radial drive shaft 13 is engaged with the bevel gear 15 attached to the outer peripheral portion of the high-speed shaft 5, and the bevel gear 16 provided at the outer end portion of the radial drive shaft 13 is connected to the accessory gear box. In this configuration, the rotation of the high-speed shaft 5 is transmitted to the accessory gear box 12 via the radial drive shaft 13 as a configuration meshed with the bevel gear 18 attached to the 12 input shafts 17.
[0004]
In the two-shaft high bypass ratio turbofan engine having such a configuration, a pressure difference of 7 to 8 atm is generated between the inside and outside of the high speed shaft 5. For example, as shown in an enlarged view in FIG. A hydraulic seal 19 having a front side seal member 20 and a rear side seal member 21 is installed between the tip portion and the low speed shaft 6.
[0005]
The front side sealing member 20 has a convex portion 23 such as a ring flange on the outer periphery of the rear end portion of the cylindrical boss portion 22, and the boss portion 22 is assembled to the low speed shaft 6. On the other hand, the rear side sealing member 21 is provided with an inward concave portion 25 on the outer periphery of the front end portion of the cylindrical boss portion 24 so that the convex portion 23 and the concave portion 25 are engaged with each other via a seal oil 31. In addition, the male screw 26 is provided on the outer peripheral surface of the boss portion 24, and the male screw 26 is screwed onto the female screw 27 provided on the inner peripheral surface of the tip portion of the high speed shaft 5, and in this case, After the cup washer 28 is clamped between the rear end surface of the boss portion 24 and the stepped surface of the female screw 27 portion of the high speed shaft 5, the convex portion 28a on the inner peripheral portion of the cup washer 28 is struck and deformed. Thus, the convex portion 28a is engaged with the concave portions 29 and 30 formed in advance on the inner diameter surface of the boss portion 24 and the high-speed shaft 5 to prevent rotation.
[0006]
In FIG. 3, 32 is a nut screwed to a male screw 33 provided on the outer periphery in the vicinity of the tip of the high speed shaft 5 in order to fix the position of the bevel gear 15 for power transmission to the accessory gear box 12. A piston ring 35 constituting a part of the hydraulic seal 19 also indicates a seal runner.
[0007]
[Problems to be solved by the invention]
However, in the case of the hydraulic seal 19 described above, the convex portion 28a of the cup washer 28 is plastically deformed to prevent the rear side seal member 21 from rotating. Therefore, the cup washer 28 must be replaced every time the engine is overhauled. In addition, each time the convex portion 28a of the cup washer 28 must be deformed, there is a problem that the work efficiency is poor. For this reason, it is conceivable to use a washer for preventing rotation on the outer diameter side, but in this case, the convex part on the outer peripheral part of the washer is deformed, so that the convex part returns to its original state due to centrifugal force and stops. May lose functionality.
[0008]
Accordingly, the present invention is intended to prevent parts from being replaced or parts to be deformed every time the engine is overhauled.
[0009]
[Means for Solving the Problems]
In order to solve the above problems, the present invention assembles a front-side seal member having a convex portion on the outer periphery of the rear end portion on the low speed shaft positioned at the shaft center portion of the engine body, and is positioned outside the low speed shaft. A rear-side seal member having an inward recess on the outer periphery of the front end is assembled to the tip of the high-speed shaft, and the projecting portion and the recess are engaged via seal oil. In the non-rotating device for the rear side seal member in the hydraulic seal, a fixing nut having grooves extending in the axial direction on the outer peripheral surface at a plurality of locations in the circumferential direction is screwed to the outer periphery of the tip portion of the high speed shaft. In addition, a groove extending in the axial direction is provided at a plurality of locations in the circumferential direction on the outer periphery of the rear end portion of the boss portion of the rear side seal member, and the rear end portion of the boss portion is disposed on the outer periphery of the front end portion of the high-speed shaft. Screwed into the front position of the nut, In addition, a key washer having a key portion along the axial direction on the inner peripheral surface is mounted between the boss portion and the outer peripheral portion of the nut so that the key portion fits into the groove of the boss portion and the nut, The key washer is configured to be detachably fixed and held by a retainer on a grip ring attached near the tip of the high-speed shaft.
[0010]
When the key washer is moved forward in the axial direction after removing the retainer, the key portion of the key washer can be detached from the groove of the nut. Therefore, the rear side sealing member can be easily disassembled when the rear end portion of the boss portion screwed to the front end portion of the high-speed shaft is rotated in a required direction.
[0011]
Further, if the number of grooves provided in the boss portion of the rear side seal member is different from the number of grooves provided in the nut, the operation of aligning the positions of both grooves becomes easy.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0013]
FIG. 1 shows an embodiment of the present invention. As shown in FIG. 2 and FIG. 3, the outer periphery of the retreated portion of the boss portion 22 is placed on the low speed shaft 6 located at the axis O portion of the engine body 9. A rear side seal having a front side seal member 20 having a convex portion 23 and a front side portion of the high speed shaft 5 located outside the low speed shaft 6 and having an inward concave portion 25 on the outer periphery of the front end portion of the boss portion 24. In the hydraulic seal 19 of the two-shaft high bypass ratio turbofan engine in which the member 21 is assembled and the convex portion 23 and the concave portion 25 are engaged with each other via the seal oil 31, The rear-side seal member 21 is prevented from rotating by using a nut 32 that fixes the power transmission bevel gear 15.
[0014]
More specifically, the high-speed shaft 5 is formed with a male screw 33 for screwing the nut 32 extending to the tip, while the nut 32 has a front half portion and a rear half portion of the outer peripheral surface. Further, a diameter difference is provided so that the front half portion has a small diameter, and a plurality of grooves 32a and 32b along the axis O direction are provided in the circumferential direction, and the boss of the rear side seal member 21 is further provided. The portion 24 is provided with a female screw 36 for screwing the male screw 33 on the inner peripheral surface of the rear end portion, and a plurality of grooves 24a along the axis O direction are provided in the circumferential direction on the outer peripheral surface of the rear end portion. Try to keep a place.
[0015]
Further, a grip ring 37 to be mounted on the high speed shaft 5, a tab washer 38 for fixing the screwing position of the nut 32 by the grip ring 37, and the boss portion 24 of the nut 32 and the rear side seal member 21 are provided. A key washer 39 for coupling and a retainer (retaining ring) 40 for holding the key washer 39 on the grip ring 37 are provided.
[0016]
The grip ring 37 has a bent shape that extends outward from the rear end surface side of the nut 32 so as to cover the latter half of the outer peripheral surface of the nut 32, and has an inward hook piece 37a at least at one location on the outer peripheral portion. And a slot 37b extending along the axis O in the center of the hook piece 37a.
[0017]
The tab washer 38 has an outer convex portion 38 a for engaging with the slot 37 b of the grip ring 37 on the outer peripheral portion, and an inner convex portion for fitting the groove 32 b in the rear half portion of the nut 32 on the inner peripheral portion. The configuration includes the portion 38b.
[0018]
The key washer 39 has a key portion 39a in the direction of the axis O that is fitted into both the groove 32a of the nut 32 and the groove 24a of the boss portion 24 of the rear side seal member 21 on the inner peripheral surface of the cup portion. The flange portion can be fixed to the hook piece 37 a of the grip ring 37 by the retainer 40.
[0019]
In addition, the groove | channel 32a of the front half part of the nut 32 is provided in the circumferential direction, for example, 12 places, and the groove | channel 24a of the boss | hub part 24 of the rear side sealing member 21 is provided in the circumferential direction, for example.
[0020]
When the rear seal member 21 is assembled to the high-speed shaft 5, the nut 32 is screwed onto the male screw 33 at the tip of the high-speed shaft 5 and tightened and held on the grip ring 37 by the tab washer 38 in FIG. As indicated by a two-dot chain line, the female screw 36 of the boss portion 24 of the rear side seal member 21 is screwed to the male screw 33 of the high speed shaft 5 with the key washer 39 fitted on the outer peripheral portion of the boss portion 24. At this time, any one groove 24a of the boss portion 24 and any one groove 32a of the nut 32 are adjusted to be aligned. In this case, the number of the grooves 24a of the boss portion 24 is 10, the number of the grooves 32a of the nut 32 is 11, and the phases are shifted from each other. Therefore, when the female screw 26 of the boss portion 24 is tightened, Even if any of the grooves 24a and 32a do not coincide with each other, if the boss portion 24 is rotated at most 36 degrees in the reverse direction, any of the grooves 24a and 32a will coincide with each other. It can be carried out. After that, the key washer 39 is shifted in the direction of the axis O, and the key portion 39a on the inner periphery of the cup portion is fitted into both the groove 24a of the boss portion 24 and the groove 32a of the nut 32, and the key The flange portion of the washer 39 is pressed against the cup washer 38 so that the hook portion 37 a of the grip ring 37 is fixedly held by the retainer 40.
[0021]
In the assembled state as described above, the rotational force acting on the rear-side seal member 21 during engine operation is transmitted from the boss portion 24 to the nut 32 via the key washer 39 and received. That is, the key portion 39a of the key washer 39 is fitted into one groove 24a of the boss portion 24 and the one groove 32a of the nut 32, and the flange portion of the key washer 39 is gripped by the retainer 40. Since it is fixed to the hook piece 37a of the ring 37 so that it cannot move in the direction of the axis O, the rear side seal member 21 is stopped by the nut 32 and is held by the grip ring 37 so as not to come out of the groove. Will be.
[0022]
On the other hand, when it is necessary to remove the rear-side seal member 21 during engine overhaul or the like, the retainer 40 engaged with the hook piece 37a of the grip ring 37 is removed, and then the key washer 39 is pivoted. After the key portion 39a is pulled out from the groove 32a of the nut 32 by shifting forward in the O direction, the rear side seal member 21 is rotated in the required direction as a whole, and the internal thread 36 on the inner peripheral portion of the boss portion 24 is moved to the high speed shaft. 5 is detached from the external thread 33 on the outer periphery of the tip.
[0023]
As described above, in the present invention, when the hydraulic seal 19 is assembled or disassembled, it is not necessary to plastically deform the non-rotating parts as in the prior art. For example, disassembly and reassembly can be performed without replacing parts.
[0024]
In the above embodiment, the case where the groove 32a for fitting the key portion 39a of the key washer 39 is provided in the nut 32 for fixing the bevel gear 15 is shown, but a fixing nut is provided separately. The nut may be provided with a groove, and the shape of the grip ring 37 in which the flange portion of the key washer 39 is fixedly held by the retainer 40 can be arbitrarily selected. Of course, various changes can be made without departing from the scope of the invention.
[0025]
【The invention's effect】
As described above, according to the anti-rotation device for the rear side seal member in the hydraulic seal of the biaxial aircraft engine of the present invention, on the low speed shaft located at the shaft center portion of the engine body, on the outer periphery of the rear end portion. A front-side seal member having a convex portion is assembled, and a rear-side seal member having an inward concave portion on the outer periphery of the front end portion is assembled to the front end portion of the high-speed shaft positioned outside the low-speed shaft, and the convex portion and the concave portion In the anti-rotation device for the rear side seal member in the hydraulic seal of the biaxial aircraft engine designed to be engaged with the seal oil, it extends in the axial direction on the outer periphery of the tip of the high speed shaft. Fixing nuts having grooves at a plurality of locations in the circumferential direction are screwed, and grooves extending in the axial direction are provided at a plurality of locations in the circumferential direction on the outer periphery of the rear end of the boss portion of the rear side seal member. Then, the rear end portion of the boss portion is screwed to the front position of the nut on the outer periphery of the tip portion of the high-speed shaft, and further, between the outer periphery of the boss portion and the nut, the inner peripheral surface is axially oriented. A key washer with a key part along the key is attached so that the key part fits into the groove of the boss part and the nut, and the key washer can be attached to and detached from the grip ring attached near the tip of the high-speed shaft with a retainer Since the retainer is removed and the key washer can be moved forward in the axial direction, the rear-side seal member can be released from the non-rotating state, so the parts are plastically deformed. It is possible to repeatedly disassemble and assemble without making it possible to improve reliability, and it is advantageous in terms of workability improvement and cost, and assembly from the outer diameter side of the high-speed shaft Therefore, it is possible to make the high-speed shaft thinner, which is advantageous in terms of downsizing the engine. Further, the number of grooves provided in the boss portion of the rear side seal member is different from the number of grooves provided in the nut. By doing so, it is possible to easily align the groove for inserting the key portion of the key washer, and the like, and so on, exhibit excellent effects.
[Brief description of the drawings]
FIG. 1 is a partially cutaway side view showing an embodiment of a detent device for a rear side seal member in a hydraulic seal of a biaxial aircraft engine of the present invention.
FIG. 2 is a schematic view of a high bypass ratio turbofan engine showing an example of a two-shaft aircraft engine.
FIG. 3 is an enlarged cross-sectional view of a part A in FIG.
[Explanation of symbols]
5 High-speed shaft 6 Low-speed shaft 9 Engine body 19 Hydraulic seal 20 Front side seal member 21 Rear side seal member 24 Boss portion 24a Groove 31 Seal oil 32 Nut 32a Groove 37 Grip ring 39 Key washer 39a Key portion 40 Retainer

Claims (2)

A front-side seal member having a convex portion on the outer periphery of the rear end portion is assembled on the low speed shaft located in the shaft center portion of the engine body, and the front end portion outer periphery is attached to the front end portion of the high speed shaft located outside the low speed shaft. A rear side seal member having an inward concave portion is assembled, and the convex portion and the concave portion are engaged with each other via a seal oil. In the device, a fixing nut having a plurality of circumferentially extending grooves extending in the axial direction on the outer peripheral surface of the front end portion of the high-speed shaft is screwed, and the rear end of the boss portion of the rear seal member A groove extending in the axial direction is provided on the outer periphery of the portion at a plurality of locations in the circumferential direction, and the rear end portion of the boss portion is screwed to the front position of the nut on the outer periphery of the tip portion of the high-speed shaft. , Between the boss and the outer periphery of the nut A key washer having a key part along the axial direction on the inner peripheral surface is mounted so that the key part fits into the groove of the boss part and the nut, and the key washer is mounted near the tip part of the high-speed shaft An anti-rotation device for a rear side seal member in a hydraulic seal of a biaxial aircraft engine, characterized in that the grip ring is detachably fixed and held by a retainer. 2. A detent device for a rear side seal member in a hydraulic seal of a biaxial aircraft engine according to claim 1, wherein the number of grooves provided in the boss portion of the rear side seal member is different from the number of grooves provided in the nut. .

Images