Strut frame and turbofan engine

Abstract

The application provides a support plate frame and a turbofan engine. The support plate frame is a fan outlet guide vane rear support plate frame of the turbofan engine, used for connecting to a downstream end of an intermediate casing, wherein: a mounting support is in a whole ring structure or is composed of multiple fan-shaped segments, and is used for connecting the intermediate casing; multiple support plate bases are arranged at intervals in a circumferential direction, and are connected to the mounting support or / and the intermediate casing; a cover plate is provided with first clamping portions, and the mounting support or / and the support plate base is provided with second clamping portions; one of the first clamping portions and the second clamping portions comprises multiple elastic clamping supports, and the other comprises multiple clamping grooves; the elastic clamping supports can be inserted into the clamping grooves, so as to clamp the cover plate to the mounting support or / and the support plate base, and limit radial and circumferential displacement of the cover plate; first positioning portions of the cover plate are matched with second positioning portions of the mounting support or / and the support plate base, so as to axially position the cover plate; and the cover plate is convenient to disassemble and assemble from a radial outer side.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of aero-engines, in particular to a strut frame and a turbofan engine. BACKGROUND

[0002] A turbojet engine generates thrust through a stream of hot gas, and is divided into axial and centrifugal types. The axial turbojet engine has become the mainstream aero-engine today due to its small cross-sectional area, high compression ratio and other characteristics.

[0003] The traditional turbojet engine structure mainly consists of an inlet, a compressor, a combustion chamber, a turbine and an exhaust nozzle. From the working principle, the turbojet engine still belongs to a heat engine, and must follow the working principle of a heat engine: energy is input at high pressure and released at low pressure, so, like a piston engine, it has four stages of air intake, pressurization, combustion and exhaust, but the difference is that the four stages of the turbojet engine are continuous, and the airflow passes through each structure of the turbojet engine in turn, and each structure completes a work.

[0004] Since the exhaust velocity of the turbojet engine is mostly supersonic, and the aircraft is mostly in subsonic cruising state, in order to better improve the propulsion efficiency of the engine, reduce the fuel consumption rate and increase the economy, the turbofan engine has emerged.

[0005] The turbofan engine belongs to a turbojet engine, and compared with the traditional turbojet engine, in addition to having the main flow passage (inner passage) of the turbojet engine, the turbofan engine increases the fan structure and the low-pressure turbine structure, so that the transmission system of the engine increases from single shaft to two shafts, and the intake airflow is also divided into two parts, one part of the airflow still enters the inner passage, is pressurized by the compressor, enters the combustion chamber for combustion, and then is discharged by the turbine to do work; the other part enters the secondary flow passage (outer passage), and is discharged to do work according to the principle of the Laval nozzle, thereby reducing the exhaust velocity and increasing the exhaust flow.

[0006] Due to the low fuel consumption ratio and other characteristics at the same thrust level, the turbofan engine has become the main civil aviation engine today.

[0007] The fan outlet guide vane (OGV) rear strut frame of the turbofan engine is an important part of the stator structure of the aero-engine, and its main functions include guiding the outer passage airflow, cooperating with the isolation of the core cabin and the outer passage, supporting various pipelines and supports, and serving as a passage for connecting the core cabin and the fan cabin for pipeline cables to pass through.

[0008] Reference Figure 1 and Figure 2The OGV rear support frame 1 of a certain type of engine is located on the downstream side of the intermediate casing 2 in the forward direction, and is assembled with cables and pipelines at the end of the engine assembly process. The OGV rear support frame 1 includes multiple support plates 11 and multiple arc-shaped frames 12. The support plates 11 extend radially and connect to the outer casing 21 of the intermediate casing 2 on the radially outer side. The arc-shaped frames 12 connect to the radially inner side of adjacent support plates 11 and connect to the inner casing 22 of the intermediate casing 2. The arc-shaped frames 12 are provided with cover plates 13 that can be removed and installed from the radially outer side. Due to the sealing and isolation function requirements, the OGV rear support frame 1 covers the first three-stage probe holes of the high-pressure compressor.

[0009] Due to the functional requirements of the supporting pipelines and brackets, as well as the limited operating space, maintenance work such as pipeline disassembly and installation, and borehole probing of the engine requires frequent and repeated disassembly and reassembly of the cover plate 13 on the OGV rear support plate frame 1. Since the OGV rear support plate frame 1 is located at the front of the core engine compartment, the installation space is limited. Furthermore, due to the need for a thinner cover plate 13 to reduce weight, the connection between the OGV rear support plate frame 1 and the arc-shaped frame 12 and the cover plate 13 is achieved by pre-arranging multiple self-locking bracket nuts and using multiple hexagonal screws to fasten them together, allowing for same-side disassembly and reassembly of fasteners. However, on the one hand, the self-locking function of the bracket nuts is prone to failure after repeated disassembly and reassembly, and the bolts are frequently damaged. On the other hand, the repeated disassembly and reassembly of multiple screws is not only time-consuming and labor-intensive, affecting maintenance efficiency, but also easily damages the structural body of the arc-shaped frame 12 and the cover plate 13, causing other problems and increasing maintenance costs and operational difficulty. Summary of the Invention

[0010] One object of the present invention is to provide a support frame whose cover plate is easy to disassemble and install from the radially outer side.

[0011] A support frame for achieving the aforementioned purpose, used to connect to the downstream end of an intermediate housing, includes a cover plate removable from the radially outer side, a mounting bracket, and multiple support plate bases. The mounting bracket is a continuous ring structure or composed of multiple sector segments, used to connect to the intermediate housing; the multiple support plate bases are spaced apart circumferentially from the mounting bracket and connected to the mounting bracket and / or the intermediate housing; wherein the cover plate is provided with a first snap-fit ​​portion, and the mounting bracket and / or the support plate bases are provided with a second snap-fit ​​portion, one of the first snap-fit ​​portion and the second snap-fit ​​portion including multiple spring-loaded brackets, and the other including multiple slots, the spring-loaded brackets being insertable into the slots to snap the cover plate onto the mounting bracket and / or the support plate bases, and to limit the radial and circumferential displacement of the cover plate; the cover plate is also provided with a first positioning portion, and the mounting bracket and / or the support plate bases are provided with a second positioning portion, the first positioning portion cooperating with the second positioning portion to axially position the cover plate.

[0012] In one or more embodiments of the support frame, the spring clip bracket is disposed radially inside the support frame.

[0013] In one or more embodiments of the support frame, the spring clip bracket includes an elastic sheet, the cross-section of which includes a V-shaped structure, the opening size of which is variable.

[0014] In one or more embodiments of the support plate frame, the first positioning part includes a first connecting lug disposed on the cover plate, the first connecting lug being provided with a first connecting hole, and the second positioning part includes a second connecting lug disposed on the support plate base, the second connecting lug being provided with a second connecting hole, the first connecting hole and the second connecting hole being connected by fasteners to axially position the cover plate.

[0015] In one or more embodiments of the support frame, the first connecting lug and the second connecting lug are disposed on the radially inner side of the support frame.

[0016] In one or more embodiments of the support frame, the first connecting lug and the second connecting lug are disposed on the downstream side of the support frame.

[0017] In one or more embodiments of the support frame, the first positioning part further includes a stop provided on the cover plate, and the second positioning part further includes a boss provided on the mounting bracket, the boss abutting against the stop to axially position the cover plate.

[0018] Another object of the present invention is to provide a turbofan engine in which the rear support frame of the fan outlet guide vanes includes a cover plate that is easily removable from the radially outer side.

[0019] A turbofan engine for achieving the aforementioned purpose includes the aforementioned support frame, wherein the support frame is the rear support frame of the fan outlet guide vanes of the turbofan engine.

[0020] The support frame of this turbofan engine connects the cover plate to the mounting bracket and / or support plate base via a spring-loaded bracket and slot, restricting the radial and circumferential displacement of the cover plate. The mounting bracket separates the cover plate's assembly and disassembly from the intermediate casing, allowing for independent radial disassembly and assembly. This protects the intermediate casing structure from damage due to repeated cover plate disassembly and assembly without adding extra assembly steps, facilitating cover plate assembly and disassembly, significantly reducing bolt disassembly and assembly time, improving assembly efficiency, and avoiding maintenance issues caused by repeated disassembly and assembly failure of the support plate nut. It also reduces the risk of structural damage to the support frame itself. The connection structure of the spring-loaded bracket and slot is simple, easy to manufacture, low in cost, and convenient and reliable in operation. Attached Figure Description

[0021] The above and other features, properties and advantages of the present invention will become more apparent from the following description taken in conjunction with the accompanying drawings and embodiments, wherein:

[0022] Figure 1 This is a schematic diagram of the intermediate casing and OGV rear support frame of a certain type of engine.

[0023] Figure 2 This is a schematic diagram showing the installation and removal of the cover plate of the OGV rear support frame of a certain engine model from the radial outside.

[0024] Figure 3 and Figure 4 These are schematic diagrams of the support plate frame according to embodiments of the present invention from different perspectives.

[0025] Figure 5 and Figure 6 This is a partial schematic diagram of the support plate frame according to an embodiment of the present invention, viewed from the radial outside.

[0026] Figure 7 and Figure 8 This is a partial schematic diagram of the support plate frame according to an embodiment of the present invention, viewed from the radial inside.

[0027] Figure 9 This is a partially exploded schematic diagram of the support plate frame according to an embodiment of the present invention.

[0028] Figure 10 This is a partial schematic diagram of the mounting bracket according to an embodiment of the present invention, viewed from the radial outside.

[0029] Figure 11 and Figure 12 This is a partial schematic diagram of the mounting bracket according to an embodiment of the present invention, viewed from the radial inside.

[0030] Figure 13 This is a schematic diagram of the first support plate base as viewed from the radial outside according to an embodiment of the present invention.

[0031] Figure 14 This is a schematic diagram of the first support plate base as viewed from the radial inside according to an embodiment of the present invention.

[0032] Figure 15 This is a schematic diagram of the second support plate base as viewed from the radial outside according to an embodiment of the present invention.

[0033] Figure 16 This is a schematic diagram of the second support plate base as viewed from the radial inside according to an embodiment of the present invention.

[0034] Figure 17 and Figure 18 This is a schematic diagram of the cover plate according to an embodiment of the present invention, viewed from the radial inside.

[0035] Figure 19 This is a schematic diagram of a spring clip holder according to one embodiment.

[0036] Figure 20 This is a schematic diagram of a spring clip holder according to another embodiment. Detailed Implementation

[0037] The following discloses various implementation methods or embodiments of the described subject matter. To simplify the disclosure, specific examples of the elements and arrangements are described below. These are merely examples and are not intended to limit the scope of protection of the present invention. It should be noted that the accompanying drawings are for illustrative purposes only and are not drawn to scale, and should not be used to limit the actual scope of protection claimed by the present invention. Furthermore, certain features, structures, or characteristics in one or more embodiments of this application can be appropriately combined.

[0038] A turbofan engine according to one or more embodiments of the present invention includes a support frame 100, which serves as the rear support frame (OGV rear support frame) of the fan outlet guide vanes of the turbofan engine and is connected to the downstream end of the intermediate casing of the turbofan engine.

[0039] In the description of this invention, it should be noted that the terms "upstream" and "downstream" refer to the relative directions of fluid flow in the fluid channel. For example, "upstream" refers to the direction from which the fluid flows, while "downstream" refers to the direction to which the fluid flows. Furthermore, in the accompanying drawings of this invention, directions F and R point to the upstream and downstream directions, respectively.

[0040] Reference Figures 3 to 9 The support frame 100 includes multiple support plates 101, cover plates 110, mounting brackets 120, and support plate bases 130.

[0041] Multiple support plates 101 extend radially along the support plate frame 100 and connect radially outward to the outer casing of the intermediate casing. The number and circumferential position of the multiple support plates 101 are designed as needed, and the included angles between the multiple support plates 101 may be the same or different.

[0042] Mounting bracket 120 is provided on the upstream side 102 of the support frame 100 for connecting the inner casing of the intermediate casing. For example, mounting bracket 120 is provided with mounting edge 121, which is connected to the downstream end of the inner casing through mounting edge 121 and fasteners.

[0043] Mounting bracket 120 can be made by Figures 10 to 12 It consists of multiple arc-shaped segments 122 as shown. The multiple arc-shaped segments 122 can be connected end to end, or they can be spaced apart in the circumferential direction. Alternatively, the mounting bracket 120 can also be a complete ring structure.

[0044] Reference Figures 3 to 9 The support plate base 130 is connected to the radially inner side of the support plate 101 and provides support for the cover plate 110. The support plate base 130 is spaced apart in the circumferential direction of the mounting bracket 120 and is connected to the mounting bracket 120, for example, through the mounting hole 140 and fasteners (not shown).

[0045] In another embodiment, the support plate base 130 may not be connected to the mounting bracket 120; for example, the support plate base 130 may be directly connected to the downstream end of the inner casing of the intermediate casing.

[0046] The support frame 100 may include various support bases 130 with different structures, such as... Figure 13 and Figure 14 The first support plate base 131 shown, and as shown Figure 15 and Figure 16 The second support plate base 132 is shown.

[0047] In the description of this invention, it should be noted that the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated.

[0048] Continue to refer to Figures 3 to 9 The cover plate 110 is an arc-shaped plate and is installed on the mounting bracket 120 and the support plate base 130. The cover plate 110 can be removed and installed from the radial outside to facilitate maintenance operations such as engine pipeline disassembly and installation, and borehole probing.

[0049] The cover plate 110 is provided with a first snap-fit ​​portion, and the mounting bracket 120 and the support plate base 130 are provided with second snap-fit ​​portions. For example, the first snap-fit ​​portion includes multiple spring-loaded brackets 150 provided in the cover plate 110, and the second snap-fit ​​portion includes multiple slots 160 respectively provided in the mounting bracket 120 and the support plate base 130. Figures 7 to 9As shown. The spring clip bracket 150 can retract to pass through the slot 160 and can open to lock onto the other side of the slot 160, as described later. Thus, the cover plate 110 can be latched to the mounting bracket 120 and the support plate base 130 by multiple spring clip brackets 150, and the radial and circumferential displacement of the cover plate 110 can be limited.

[0050] Reference Figures 18 to 20 The spring clip bracket 150 includes an elastic sheet 151 and a base 152. The base 152 can be connected to the body 111 of the cover plate 110 by welding, riveting, high-temperature fusion, or other means, for example... Figure 19 and Figure 20 The spring clip bracket 150 shown is used to connect to the body 111 via high-temperature fusion and riveting. The cross-section of the elastic sheet 151 includes a V-shaped structure, for example formed by sheet metal. The opening 153 of the V-shaped structure is variable in size. When the opening 153 is in a contracted state, the V-shaped structure can pass through the slot 160. When the opening 153 is in an open state, the V-shaped structure can be prevented from exiting the slot 160, thereby snapping the cover plate 110 onto the mounting bracket 120 and / or the support plate base 130.

[0051] Reference Figures 7 to 9 Optionally, the spring clip bracket 150 is disposed on the radially inner side of the support plate frame 100, and the clip slot 160 passes radially through the mounting bracket 120 and the support plate base 130, thereby facilitating the installation of the cover plate 110 from the radially outer side and reducing the impact on the airflow of the bypass duct of the turbofan engine.

[0052] In another embodiment, the slot 160 may be provided only in the support plate base 130, that is, the cover plate 110 is only snapped into the support plate base 130, and the cover plate 110 and the mounting bracket 120 may overlap. The two circumferential sides of the cover plate 110 are respectively installed to the adjacent support plate base 130 through the spring clip bracket 150, thereby snapping the cover plate 110 into the support plate base 130 and restricting the radial and circumferential displacement of the cover plate 110.

[0053] In another embodiment, multiple slots 160 may be provided only in the mounting bracket 120, that is, the cover plate 110 is only snapped into the mounting bracket 120, and the cover plate 110 and the support plate base 130 may overlap. The multiple slots 160 may be in the same or different positions in the axial direction of the mounting bracket 120, thereby snapping the cover plate 110 into the mounting bracket 120 and limiting the radial and circumferential displacement of the cover plate 110.

[0054] In other embodiments, the elastic sheet 151 may be configured in other shapes, or the spring clip bracket 150 may adopt other structures. For example, the spring clip bracket 150 may include a retractable lock cylinder (not shown). The retraction direction of the lock cylinder may be set to be parallel to the axial or tangential direction of the cover plate 110. The mounting bracket 120 and / or the support plate base 130 may be provided with a slot 160 corresponding to the lock cylinder. When the lock cylinder is extended, it may be inserted into the slot 160, thereby snapping the cover plate 110 onto the mounting bracket 120 and / or the support plate base 130 and limiting the radial and circumferential displacement of the cover plate 110. When the lock cylinder is retracted, it may be withdrawn from the slot 160 to realize the disassembly and assembly of the cover plate 110.

[0055] In some other embodiments, multiple card slots 160 may be provided on the cover plate 110, and multiple spring card brackets 150 may be provided on the mounting bracket 120 and / or the support plate base 130.

[0056] The cover plate 110 is also provided with a first positioning part, and the mounting bracket 120 or / and the support plate base 130 are provided with a second positioning part. The first positioning part and the second positioning part cooperate to perform axial positioning of the cover plate 110, as detailed below.

[0057] Reference Figures 6 to 9 , Figures 13 to 18 The first positioning part includes a first connecting lug 112 disposed on the cover plate 110, and the first connecting lug 112 is provided with a first connecting hole 113. The second positioning part includes a second connecting lug 133 disposed on the support plate base 130, and the second connecting lug 133 is provided with a second connecting hole 134. The first connecting hole 113 and the second connecting hole 134 are connected by a fastener 170 to axially position and fasten the cover plate 110.

[0058] Optionally, the first connecting lug 112 and the second connecting lug 133 are disposed on the radially inner side of the support frame 100 to reduce the impact on the bypass airflow of the turbofan engine.

[0059] Optionally, the first connecting lug 112 and the second connecting lug 133 are disposed on the downstream side 103 of the support frame 100. Since the downstream side 103 of the support frame 100 has a large operating space, it is convenient to install and remove the fastener 170.

[0060] Reference Figure 7 Optionally, the first positioning part further includes a stop 114 provided on the cover plate 110, and the second positioning part further includes a boss 123 provided on the mounting bracket 120. The boss 123 abuts against the stop 114 to axially position the cover plate 110.

[0061] The installation method of the cover plate 110 is described below with reference to one or more embodiments:

[0062] 1. Insert the spring clip bracket 150 of the cover plate 110 into the slot 160 of the mounting bracket 120 and / or the support plate base 130 from the radial outside, so that the V-shaped structure of the spring clip bracket 150 contracts under the compression of the slot 160, or the V-shaped structure contracts by squeezing by hand or by clamping the elastic piece 151 with a tool, so that it passes through the slot 160. After passing through the slot 160, the V-shaped structure automatically opens and is locked on the radial inside of the slot 160, thereby detachably connecting the cover plate 110 to the mounting bracket 120 and / or the support plate base 130, and restricting the radial and circumferential displacement of the cover plate 110 by multiple spring clip brackets 150;

[0063] 2. Finely adjust the cover plate 110 after it is inserted into the slot 160 along the axial direction so that its stop 114 engages with the boss 123 on the mounting bracket 120, thereby achieving axial positioning of the cover plate 110. Figure 7 As shown;

[0064] 3. For example Figure 6 and Figure 8 As shown, the first connecting lug 112 of the cover plate 110 is connected to the second connecting lug 133 of the support plate base 130 by fastener 170. The axial positioning and fastening of the cover plate 110 are achieved by the stop 114 and the boss 123, and the cover plate 110 is prevented from being opened accidentally during engine operation.

[0065] When disassembling the cover plate 110, remove the fastener 170, and by squeezing or clamping the elastic piece 151 with a tool, the V-shaped structure will shrink, and the spring clip bracket 150 can be removed from the slot 160.

[0066] The support frame 100 of this turbofan engine connects the cover plate 110 to the mounting bracket 120 and / or the support plate base 130 via a spring-loaded bracket 150 and a slot 160, restricting the radial and circumferential displacement of the cover plate 110. The mounting bracket 120 separates the disassembly and assembly of the cover plate 110 from that of the intermediate housing, allowing for independent radial disassembly and assembly of the cover plate 110. This protects the related structures of the intermediate housing from damage due to repeated disassembly and assembly of the cover plate 110, without adding extra assembly steps. This facilitates the disassembly and assembly of the cover plate 110, significantly reducing bolt disassembly and assembly time, improving assembly efficiency, and avoiding maintenance problems caused by the failure of the support plate nut after repeated disassembly and assembly, thus reducing the risk of structural damage to the support frame 100. The connection structure of the spring-loaded bracket 150 and the slot 160 is simple, easy to manufacture, low in cost, and convenient and reliable in operation.

[0067] While the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the invention. Any variations and modifications can be made by those skilled in the art without departing from the spirit and scope of the invention. Therefore, any modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention, without departing from the scope of the invention, fall within the protection scope defined by the claims of the present invention.

Claims

1. A support frame for connection to the downstream end of an intermediate housing, comprising a cover plate removable from the radially outer side, characterized in that, The support frame also includes: The mounting bracket is a complete ring structure or composed of multiple sector segments, used to connect the intermediate housing; Multiple support plate bases are spaced apart in the circumferential direction of the mounting bracket and connected to the mounting bracket and / or the intermediate housing; The cover plate is provided with a first snap-fit ​​portion, and the mounting bracket and / or the support plate base is provided with a second snap-fit ​​portion. One of the first snap-fit ​​portion and the second snap-fit ​​portion includes multiple spring-loaded brackets, and the other includes multiple slots. The spring-loaded brackets can be inserted into the slots to snap the cover plate onto the mounting bracket and / or the support plate base, and to limit the radial and circumferential displacement of the cover plate. The cover plate is also provided with a first positioning portion, and the mounting bracket and / or the support plate base is provided with a second positioning portion. The first positioning portion and the second positioning portion cooperate to axially position the cover plate. The spring clip bracket is located on the radial inner side of the support plate frame.

2. The support frame as described in claim 1, characterized in that, The spring clip bracket includes an elastic sheet, the cross-section of which includes a V-shaped structure, and the opening size of the V-shaped structure is variable.

3. The support plate frame as described in any one of claims 1-2, characterized in that, The first positioning part includes a first connecting lug disposed on the cover plate, the first connecting lug being provided with a first connecting hole; the second positioning part includes a second connecting lug disposed on the support plate base, the second connecting lug being provided with a second connecting hole; the first connecting hole and the second connecting hole are connected by fasteners to axially position the cover plate.

4. The support frame as described in claim 3, characterized in that, The first connecting lug and the second connecting lug are disposed on the radial inner side of the support frame.

5. The support frame as described in claim 3, characterized in that, The first connecting lug and the second connecting lug are disposed on the downstream side of the support frame.

6. The support frame as described in claim 3, characterized in that, The first positioning part further includes a stop provided on the cover plate, and the second positioning part further includes a boss provided on the mounting bracket. The boss abuts against the stop to axially position the cover plate.

7. A turbofan engine, characterized in that, Includes the support plate frame as described in any one of claims 1-6, wherein the support plate frame is the rear support plate frame of the fan outlet guide vanes of the turbofan engine.

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