CN209724782U - Gas turbine and its fan spindle bearing support construction - Google Patents
Gas turbine and its fan spindle bearing support construction Download PDFInfo
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- CN209724782U CN209724782U CN201920469627.XU CN201920469627U CN209724782U CN 209724782 U CN209724782 U CN 209724782U CN 201920469627 U CN201920469627 U CN 201920469627U CN 209724782 U CN209724782 U CN 209724782U
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Abstract
Gas turbine and its fan spindle bearing support construction are provided, support construction therein simultaneously can be when fan blade be broken or falls off, it can be reduced unbalanced load, the fan spindle bearing support construction includes inner cone wall and connector, and inner cone wall has big end and small end, and small end provides the mounting portion for the installation of forefan bearing, connector is for being connected to Middle casing, big end is provided with internal screw thread, and connector is provided with sliding surface, is configured with external screw thread on sliding surface；Internal screw thread is connected with external screw thread, and internal screw thread and external screw thread alternative one are arranged to fusing structure, is broken when fan blade falls off as sacrifice mems using being allowed in；Sliding surface allows big end after fusing structure fracture in being slided on sliding surface；Big end and connector alternative one also provide position limiting structure, fall off to limit big end in the sliding surface of connector.
Description
Technical field
The utility model relates to the fan spindle bearing support constructions of gas turbine more particularly to gas turbine.
Background technique
The low pressure rotor of typical fanjet generally comprises fan, booster stage, low-pressure turbine and shaft etc., wherein shaft
It is supported by multiple bearings, power and torque that turbine generates is transmitted to booster stage and fan.Under normal circumstances, fan, booster stage
It is overlapped with the straight line where each component center of gravity such as low-pressure turbine with shaft.For the nargin for guaranteeing critical speed, low pressure rotor system
It is generally supported by three bearings, wherein 1# bearing and 2# bearing are located near fan propeller, referred to as fan spindle bearing.Fan spindle bearing is logical
When crossing supporting structure fan propeller is connected on stator part Middle casing, therefore working normally, fan spindle bearing and its bearing knot
Structure is the force transferring part between the stator structures such as fan and Middle casing.
In aero-engine operational process, since the factors such as foreign object sucking or fatigue cause fan blade to be broken or fall off,
That is FBO (Fan Blade Off).After FBO event occurs, the center of gravity of fan can deviate the center line of low pressure rotor.However, due to
The limitation of bearing, fan are still rotated around the center line of low pressure rotor.Fan can motivate low pressure to turn around the axis rotation for deviateing its center of gravity
Subsystem generates one or more Oscillatory mode shapes, to generate unbalanced load.For big culvert common on current commercial aircraft
Road is than fanjet, and half path length of fan blade, quality are big, and FBO event will lead in the center of gravity line and engine of fan
Heart line misaligns, and causes huge unbalanced load.Since bearing radially constrains fan shaft, therefore FBO unbalanced load is main
It is transmitted on Middle casing, and is further transferred on installation section even aircraft by bearing and its supporting structure.
Since FBO event itself is difficult to avoid, traditional design method is by improving related components in Path of Force Transfer
The structural strength of (such as Middle casing, installation section, thrust pull rod), can bear FBO unbalanced load, to meet safety
Property require.However, this method will lead to the quality and increased costs of engine, fuel consumption rate is increased, when engine is not sent out
Whole efficiency is low when the case where raw sizable rotor unbalance.Another kind should be to carry out structure to the effective ways of FBO event
Failure/fusing design.Structural failure/fusing design concept are as follows: by being purposefully designed as components certain in engine
Unit is sacrificed, it is made to fail under FBO load, is on the one hand reduced, the uneven energy that consumption FBO event generates, on the other hand
Change transmission path, redistribute FBO load, reduces the unbalanced load for being transmitted to critical component, protect the peace of engine
Entirely.The unbalanced load that FBO event generates is mainly by fan spindle bearing (1# bearing or forefan bearing and 2# bearing or rear fan axis
Hold), the carrying such as bearing support structure and Middle casing.By to the fan spindle bearing and its components such as supporting structure in Path of Force Transfer
Failure Design is carried out, lesser strength assurance coefficient is made it have, fails under FBO unbalanced load, intermediary machine can be reduced
The FBO unbalanced load that the key components and parts such as casket, installation section and low-pressure spool are born, guarantees the safety of engine.
A kind of common fusing form is to tighten bolt in the prior art, such as patent FR2752024B1, is supported in 1# bearing
Bore and connect with Middle casing at the installation side of wall using constriction bolt, after FBO constriction bolt by pulling force the tensile failure at deflation,
Due to bolt circumferentially be it is discontinuous, the response of bolt failure is less continuous.Cone wall leading portion is easy to touch with fan shaft after falling off
It hits, fan shaft damage is caused even to destroy.Furthermore each bolt tightens processing dimension, bolt installation condition and the pretightning force meeting of section
There is certain difference, this will affect the stability of fusing activation threshold value.
Another common fusing form is that thinning section is set on the support cone wall of 1# bearing such as patent US6447248B1
Set thinning section, when FBO occurs, thinning section buckling failure, cutting 1# bearing to Middle casing Path of Force Transfer, this patent for
The processing request for boring wall is very high, because the support cone wall of 1# bearing is a large-sized thin-wall annular part, processes on cone wall
Thinning section be easy to cause cone wall deformation, and the dimensional accuracy of thinning section is also difficult to meet the requirements, and buckling load is to thinning section thickness
It is very sensitive with the precision of shape, thinning section scheme will cause processing cost significantly rise and the drop of buckling load value stability
Low, cone wall can collide after falling off with fan shaft, and fan shaft damage is caused even to destroy.
Utility model content
The purpose of the utility model is to provide a kind of fan spindle bearing support constructions, are used to fan being installed to Middle casing
On, and unbalanced load can be can be reduced when fan blade is broken or falls off.
Another purpose of the utility model is to provide a kind of gas turbine comprising aforementioned fan spindle bearing support construction.
A kind of fan spindle bearing support construction, including inner cone wall and connector, the inner cone wall has big end and small end, described
Small end provides the mounting portion for the installation of forefan bearing, and the connector is for being connected to Middle casing, in which:
The big end is provided with internal screw thread, and the connector is provided with sliding surface, is configured with external screw thread on the sliding surface；
The internal screw thread is connected with the external screw thread, and the internal screw thread and the external screw thread alternative one are arranged to fuse
Structure is broken when fan blade falls off as sacrifice mems using being allowed in；The sliding surface allows the big end described molten
It is slided after disconnected structural break on the sliding surface；
The big end and the connector alternative one also provide position limiting structure, fall off to limit the big end in described
The sliding surface of connector.
In at least one embodiment, the form of thread width of the internal screw thread of the big end of the inner cone wall is wanted
Greater than the externally threaded form of thread width on the sliding surface of the connector, the external screw thread is arranged to described molten
Disconnected structure.
In at least one embodiment, the position limiting structure includes the sliding surface of the connector in the outer spiral shell
The front side of line is spaced the baffle ring of one end distance setting, and the outer diameter of the baffle ring is greater than the path of the internal screw thread.
In at least one embodiment, the external screw thread or internal screw thread for being arranged to the fusing structure are in tooth form root
Construct necking section.
In at least one embodiment, the wall thickness of the big end of the inner cone wall is greater than in the middle part of the inner cone wall
Wall thickness.
In at least one embodiment, the sliding surface remains with one section in the externally threaded front side and/or rear side
Spherical surface.
In at least one embodiment, the connector is bolt-connected to Middle casing.
In at least one embodiment, the sliding surface is the conical surface or spherical surface, the center line of the sliding surface or center
The axis setting of the low-pressure shaft of corresponding forefan bearing support.
In at least one embodiment, the tooth form of the external screw thread and the internal screw thread is isosceles trapezoid.
A kind of gas turbine, such as aero-engine, including low pressure rotor, the low pressure rotor include fan and fan
Axis, wherein the fan shaft is connected on Middle casing by any fan spindle bearing support construction.
In aforementioned schemes, screw thread is ring structure, and FBO occurs for the fan blade under any angle, and helicitic texture can
Be quickly invalidated, play the role of fusing, inner cone wall big end installation at and corresponding connector install while at process screw thread knot
Structure, the rigidity that this installs side at two is big, and machining is unlikely to deform, and reduces difficulty of processing and processing cost.
Detailed description of the invention
The above and other feature, property and advantage of the utility model will be by with reference to the accompanying drawings and examples
Description and become readily apparent from, in which:
Fig. 1 is the front-end view according to the gas turbine of one or more embodiments.
Fig. 2 is the enlarged drawing according to the inner cone wall of one or more embodiments and the threaded connection place of connector.
Fig. 3 is the schematic diagram according to the fusing failure of the threaded connection place of one or more embodiments.
Fig. 4 is the front-end view according to the gas turbine of the fusing structure of one or more embodiments failure front and back.
Fig. 5 is the schematic diagram according to the sliding spherical surface of one or more embodiments.
Fig. 6 is the schematic diagram according to the fusing structure of one or more embodiments.
Specific embodiment
It is following to disclose the embodiment or embodiment of subject technology scheme described in a variety of different implementations.For simplification
The specific example of each element and arrangement is described below in disclosure, and certainly, these are only example, is not to this
The protection scope of utility model is limited.Such as the fisrt feature then recorded in the description above second feature or
It is formed above, may include the embodiment that the first and second features are formed by way of directly contacting, also be included in
The embodiment that supplementary features are formed between one and second feature, to can not directly be contacted between the first and second features.
In addition, in these disclosures may in different examples repeat reference numerals and/or letter.The repetition is in order to brief
With it is clear, itself do not indicate each embodiment being discussed and/or interstructural relationship.Further, when first element is
It is described with the mode for being connected with second element or combining, which includes that the first and second elements are connected directly or are bonded to each other
Embodiment, also include made using one or more other intervening elements additions the first and second interelements ground connection be connected or that
This is combined.In the examples described below, the flow direction of forward and backward air-flow is reference.
Fan spindle bearing support construction shown in fig. 1 is applied to fanjet comprising inner cone wall 6 and connector 8.Turbofan
The fan shaft 3 of engine is supported in the fan spindle bearing support construction by forefan bearing 4 and rear fan bearing 5, the fan
Bearing support structure is connected on Middle casing 9.
The small end of the left end with the big end positioned at right end in figure and in figure of inner cone wall 6, small end, which provides, is used for forefan
The mounting portion that bearing 4 is installed, connector 8 is for being connected to Middle casing 9.It is screw thread in corresponding diagram 1 referring concurrently to Fig. 2, Fig. 2
The enlarged diagram of junction.Big end is provided with internal screw thread 23, and connector 8 is provided with sliding surface 27, is configured on sliding surface 27
External screw thread 22.Internal screw thread 23 and external screw thread 22 connect, and external screw thread 22 is arranged to fusing structure, i.e., in load from preceding fan spindle bearing 4
It is transmitted in the Path of Force Transfer of Middle casing 9, the intensity of external screw thread 22 is disposed relative to other strength of parts and wants low.Therefore,
After FBO event occurs, unbalanced load caused by fan imbalance rotates will lead to external screw thread 22 and be broken first, thus will not
Balancing load blocks, it is avoided to be transmitted to Middle casing.Baffle ring 21,21 company of can be of baffle ring are constructed in the left end of sliding surface 27
Continuous or multiple discrete blocks are distributed in a ring, after being fused due to external screw thread 22 by unbalanced load, inner cone wall 6
Big end is slided on sliding surface 27, and the internal screw thread 23 on inner cone wall 6 is not broken, and slides the blocking by baffle ring 21, therefore
Inner cone wall 6 will not fall off in connector 8, and secondary pulse occurs with fan shaft after preventing inner cone wall from falling off and destroys.
Sliding surface 27 distinguishes the face that retention gap length is L1 and L2 in the front side of threaded connection place and rear side, for preceding
Cone wall 6 occurs in FBO event and is slided after fusing structure fracture.The internal screw thread 23 not being broken is in front side by baffle ring 21
Blocking, in blocking of the rear side by Middle casing 9, therefore will not fall off in connector 8.
There is also multiple modifications for aforementioned embodiments, such as internal screw thread is arranged to fusing structure, and external screw thread 22 is not broken,
Correspondingly, corresponding retaining ring or baffle ring are set in the big end of inner cone wall 6, limit the movement of external screw thread 22, can also play prevents
The case where inner cone wall 6 and connector 8 fall off.For another example, aforementioned embodiments are the screw thread and baffle ring phase by not fusing
Effect is played the role of constraining inner cone wall 6, but can also pass through gear by the way that baffle ring is respectively set on inner cone wall 6 and connector 8
Ring and baffle ring interact, to constrain inner cone wall 6.
As shown in Fig. 2, the form of thread width D 1 of the internal screw thread 23 of the big end of inner cone wall 6 is greater than the sliding of connector 8
The form of thread width D 2 of external screw thread 22 on face 27.Screw thread can be formed by turning.Since D1 is greater than D2, external screw thread
22 intensity is less than the intensity of internal screw thread 23, and internal screw thread 23 is arranged to fusing structure at this time, can be by simply processing
Technique can be realized.
As shown in fig. 6, the tooth form root configurations of external screw thread 22 go out necking section 24, external screw thread 22 is arranged to fusing structure,
Necking section 24 can promote the sensitivity of its fusing.
As shown in figure 5, sliding surface 27 is not limited to circular conical surface, spherical surface, the center line of sliding surface or center pair can also be
The axis 12 of the low-pressure shaft of forefan bearing support is answered to be arranged.
In the foregoing embodiment, the tooth form of external screw thread 22 and internal screw thread 21 is isosceles trapezoid, but not limited to this, it can also be with
It is triangle or other shapes, as long as being suitable for connection.
As shown in Figure 1, the front end of fan shaft 3 is by forefan bearing 4 and 5, rear fan bearing when engine work
It holds.When leaf abscission FBO event occurs for fan blade 1, huge shock loading and unbalanced load are transmitted by fan disk 2
To fan shaft 3, fan shaft 3 transfers loads to a big chunk load on inner cone wall 6 by forefan 4, then passes through connection
Part 8 is transmitted on Middle casing 9；Another part load is transmitted on Middle casing 9 by fan shaft 3 by rear fan bearing 5.In
It will bear very big FBO load on Jie's casing 9, but due to that can fail in the setting of the junction of inner cone wall 6 and Middle casing 9
Helicitic texture 7, the Path of Force Transfer decoupling between such forefan and Middle casing 9, moment of flexure caused by being transmitted by forefan will not
It is transmitted on Middle casing, rotor also becomes overcritical from subcritical, there is Self-centering Action.
When FBO event occurs, as shown in figure 3, external screw thread 22 fails, inner cone wall 6 can on connector 8 along
Gap L1 and L2 are mobile, i.e. the swing freedom degree of inner cone wall 6 is released, and the bending load that FBO is generated is not transferred to intermediary machine
On casket 9, the pendulum radius of fan propeller becomes larger, as shown in figure 4, accelerating to touch mill, rotor between fan blade and fancase
Revolving speed reduces, square directly proportional due to unbalanced load and revolving speed, so unbalanced load also sharply declines.It is only very small by one
Fractional load is transmitted by inner cone wall 6, and thread 21 and Middle casing 9 play the role of limitation inner cone wall 6 and fall off, and prevents cone wall de-
Lag behind the destruction that fan shaft collides and causes axis.
In order to discharge the swing freedom degree of fan shaft preferably at helicitic texture, the mounting surface of connector 8 is preferably ball
Face, as shown in figure 5, the centre of sphere of spherical surface 27, in engine low-pressure shaft rotary shaft 12, after FBO occurs, helicitic texture failure is preceding
Wall 6 is bored to slide along the spherical surface 27 of connector 8.
In the foregoing embodiment, give engine bring huge unbalanced load to reduce FBO event, while in order to subtract
The weight of light engine, improves business efficiency, proposes a kind of screw connection structure that can be failed, is avoided that thinning section scheme
Be not easy to machine, tighten bolt scheme dispersibility it is big the problems such as, have the effect that
1. inner cone wall big end installation at and when corresponding connector is installed at process helicitic texture, this is installed at 2
The rigidity on side is big, and machining is unlikely to deform, and reduces difficulty of processing and processing cost；
2. shock loading and unbalanced load are transmitted to forefan bearing when FBO occurs for fan blade at any angle
At the installation side of Middle casing, screw connection structure can fail in time, after helicitic texture failure, forefan bearing support cone wall
It can be slided along sliding surface, release moment of flexure caused by unbalanced load；It is threadedly coupled failure, load is interrupted from 1# and is transferred to intermediary
The path of casing prevents the main load-carrying construction failure such as Middle casing；
3. inner cone wall can be slided along sliding surface after being threadedly coupled failure, the bending freedom degree of inner cone wall is released, is increased
The pendulum radius of fan propeller increases and touches mill amount between fan blade and fancase, accelerates the moderating process of rotor, uneven
The load that weighs is directly proportional to rotor speed square, so significantly reducing unbalanced load.
4. being threadedly coupled failure, fan propeller critical speed is reduced, rotor becomes overcritical from subcritical, has self-centering
Effect slows down unbalanced load；
5. screw thread is ring structure, FBO occurs for the fan blade under any angle, and helicitic texture can be quickly invalidated, and rises
It is acted on to fusing.
Although the utility model is disclosed as above with preferred embodiment, its be not for limiting the utility model, it is any
Those skilled in the art without departing from the spirit and scope of the utility model, can make possible variation and modification.Cause
This, all contents without departing from technical solutions of the utility model, according to the technical essence of the utility model to above embodiments institute
Any modification, equivalent variations and the modification made, each fall within the protection scope that the utility model claims are defined.
Claims (10)
1. fan spindle bearing support construction, including inner cone wall and connector, the inner cone wall has big end and small end, and the small end mentions
For the mounting portion installed for forefan bearing, the connector is for being connected to Middle casing, which is characterized in that
The big end is provided with internal screw thread, and the connector is provided with sliding surface, is configured with external screw thread on the sliding surface；
The internal screw thread is connected with the external screw thread, and the internal screw thread and the external screw thread alternative one are arranged to fusing knot
Structure is broken when fan blade falls off as sacrifice mems using being allowed in；The sliding surface allows the big end in the fusing
It is slided after structural break on the sliding surface；
The big end and the connector alternative one also provide position limiting structure, fall off to limit the big end in the connection
The sliding surface of part.
2. fan spindle bearing support construction as described in claim 1, which is characterized in that the big end of the inner cone wall it is described
The form of thread width of internal screw thread is greater than the externally threaded form of thread width on the sliding surface of the connector,
The external screw thread is arranged to the fusing structure.
3. fan spindle bearing support construction as claimed in claim 2, which is characterized in that the position limiting structure includes the connector
The sliding surface be spaced the baffle ring of one end distance setting in the externally threaded front side, the outer diameter of the baffle ring is greater than in described
The path of screw thread.
4. fan spindle bearing support construction as described in claim 1, which is characterized in that be arranged to the described outer of the fusing structure
Screw thread or internal screw thread go out necking section in tooth form root configurations.
5. fan spindle bearing support construction as described in claim 1, which is characterized in that the wall thickness of the big end of the inner cone wall
The wall thickness being greater than in the middle part of the inner cone wall.
6. fan spindle bearing support construction as described in claim 1, which is characterized in that the sliding surface it is described it is externally threaded before
Side and/or rear side remain with one section of spherical surface.
7. fan spindle bearing support construction as described in claim 1, which is characterized in that during the connector is bolt-connected to
Jie's casing.
8. fan spindle bearing support construction as described in claim 1, which is characterized in that the sliding surface is the conical surface or spherical surface, institute
The center line or center of stating sliding surface correspond to the axis setting of the low-pressure shaft of forefan bearing support.
9. fan spindle bearing support construction as described in claim 1, which is characterized in that the tooth of the external screw thread and the internal screw thread
Type is isosceles trapezoid.
10. a kind of gas turbine, including low pressure rotor, the low pressure rotor includes fan and fan shaft, which is characterized in that described
Fan shaft is connected on Middle casing by fan spindle bearing support construction as claimed in any one of claims 1-9 wherein.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920469627.XU CN209724782U (en) | 2019-04-09 | 2019-04-09 | Gas turbine and its fan spindle bearing support construction |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920469627.XU CN209724782U (en) | 2019-04-09 | 2019-04-09 | Gas turbine and its fan spindle bearing support construction |
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| Publication Number | Publication Date |
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| CN209724782U true CN209724782U (en) | 2019-12-03 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201920469627.XU Active CN209724782U (en) | 2019-04-09 | 2019-04-09 | Gas turbine and its fan spindle bearing support construction |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114687861A (en) * | 2022-05-31 | 2022-07-01 | 成都中科翼能科技有限公司 | Locking connection device of gas turbine low-pressure rotor |
| CN114810663A (en) * | 2022-04-21 | 2022-07-29 | 中国科学院工程热物理研究所 | Rear force bearing structure of centrifugal/oblique flow compressor |
-
2019
- 2019-04-09 CN CN201920469627.XU patent/CN209724782U/en active Active
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114810663A (en) * | 2022-04-21 | 2022-07-29 | 中国科学院工程热物理研究所 | Rear force bearing structure of centrifugal/oblique flow compressor |
| CN114810663B (en) * | 2022-04-21 | 2022-11-01 | 中国科学院工程热物理研究所 | Rear force bearing structure of centrifugal/oblique flow compressor |
| CN114687861A (en) * | 2022-05-31 | 2022-07-01 | 成都中科翼能科技有限公司 | Locking connection device of gas turbine low-pressure rotor |
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