CN106840590B - A kind of five component dynamic pitching balance of miniaturized large-load integral type - Google Patents
A kind of five component dynamic pitching balance of miniaturized large-load integral type Download PDFInfo
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- CN106840590B CN106840590B CN201611195748.7A CN201611195748A CN106840590B CN 106840590 B CN106840590 B CN 106840590B CN 201611195748 A CN201611195748 A CN 201611195748A CN 106840590 B CN106840590 B CN 106840590B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M9/00—Aerodynamic testing; Arrangements in or on wind tunnels
- G01M9/06—Measuring arrangements specially adapted for aerodynamic testing
- G01M9/062—Wind tunnel balances; Holding devices combined with measuring arrangements
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Abstract
A kind of five component dynamic pitching balance of miniaturized large-load integral type, including pitching balance inner core, pitching balance outer wall, shaft, strain beam, housing screw and sliding bearing.The present invention uses inside and outside fabricated structure: pitching balance inner core includes head circular conical surface section, non-uniform beam, cooperation section and driving beam, cooperates and is provided with circular through hole and rectangular through-hole in section；Pitching balance outer wall is tubular structure, including hollow cooperation section and tail portion circular conical surface section, is provided with circular through hole and rectangular through-hole in hollow cooperation section；Shaft passes through circular through hole and is combined together pitching balance outer wall and pitching balance inner core, and strain beam passes through rectangular through-hole to measure the corner of pitching balance inner core.Structure of the invention is rationally compact, small in size, and carrying normal load is big, and precision is high, has great application value in field of aerospace, is that one kind expands normal static strain balance measuring principle, parameter, range and the sophisticated sensor using function significantly.
Description
Technical field
The present invention relates to a kind of five component dynamic pitching balances of miniaturized large-load integral type, belong to wind tunnel test technology neck
Domain.
Background technique
When carrying out Design of Flight Control and space vehicle dynamic attributional analysis, flight force and moment is with aerodynamic derivative shape
Formula occurs, i.e., quiet, dynamic stability derivative, due to mechanism of production complexity, usually obtains above-mentioned parameter using forced vibration wind tunnel test.
Dynamic derivative wind tunnel test is using model oscillation come the rigid motion mode of simulated flight device to obtain dynamic derivative.With
The development of high-speed aircraft, guided missile, rocket and reentry vehicle, flight quality and dynamic stability problem be increasingly taken seriously, move
Derivative test also becomes more and more important.Especially supersonic speed, high-supersonic speed range and significantly disturbance and a wide range of motor-driven
Under the conditions of test and measuring technique, including balance system, model and support system require to optimize.
According to the wind tunnel test mission requirements of the symmetrical aircraft in novel face, one side aircraft normal load is big, to solve
Load and Rigidity Matching problem, development of new dynamic scale technology is with the dynamic test ability of forming face symmetrical flight device.It is another
Aspect, it is desirable that while the static derivative and dynamic derivative of precise measurement aircraft.Current dynamic pitching balance uses five COMPONENT BALANCEs
With the form of simple component hinge tandem combination, axial dimension is big after combination, and space occupancy rate is high, is not suitable for low aspect ratio and flies
The test of row device.And the distance between the combined type balance school heart and shaft are big, it is insufficient on test accuracy.
The characteristics of symmetrical aircraft in novel face, mainly normal load was much larger than transverse load, for this reason, it may be necessary to a kind of small-sized
Change the dynamic pitching balance of big load integral type to solve the above problems, is able to carry out the dynamic wind-tunnel examination of this kind of aircraft
It tests.
Summary of the invention
Technology of the invention solves the problems, such as: overcome the deficiencies in the prior art, proposes a kind of miniaturized large-load integral type
Five component dynamic pitching balances occupy small volume, and enhance the rigidity and bearing capacity of balance, and realize dynamic test
Required Oscillation Amplitude.
The technical solution of the invention is as follows:
A kind of five component dynamic pitching balance of miniaturized large-load integral type, comprising: outside pitching balance inner core, pitching balance
Wall, shaft, strain beam, housing screw, sliding bearing；
Pitching balance inner core includes head circular conical surface section, non-uniform beam, cooperation section and driving beam, and non-uniform beam is for measuring
Five component aerodynamic loadings cooperate and are provided with circular through hole and rectangular through-hole in section, and pitching balance outer wall is tubular structure, including sky
The heart cooperates section and tail portion circular conical surface section, is provided with circular through hole and rectangular through-hole in hollow cooperation section；
Pars intramuralis is arranged outside pitching balance in pitching balance inner core, and sliding bearing sleeve passes through pitching day outside shaft
Pitching balance outer wall and pitching balance inner core are combined together by the circular through hole on flat outer wall and pitching balance inner core, strain
Beam passes through the rectangular through-hole on pitching balance outer wall and pitching balance inner core, for measuring the corner of pitching balance inner core；It compresses
Strain beam and shaft are fixed on pitching balance outer wall by screw.
The driving beam of pitching balance inner core is located at the hollow cooperation intersegmental part of pitching balance outer wall, and hollow cooperation section is interior
Diameter is greater than the maximum radial dimension of driving beam.
Maximum radial dimension greatly at least 10mm of the internal diameter of hollow cooperation section than driving beam.
Pitching balance inner core rotates around the axis, and rotational steps are not less than 1 °.
The head circular conical surface section of pitching balance inner core is 1:10 circular conical surface, and the tail portion circular conical surface section of pitching balance outer wall is 1:
10 circular conical surfaces.
Be arranged on the driving beam tail end face of pitching balance inner core it is fluted, for driving pitching balance inner core to revolve around the shaft
Turn, realizes pitching simple harmonic motion.
The non-uniform beam of pitching balance inner core is stretch section, and maximum is respectively subjected to 10000N normal force and 120Nm pitching power
Square load.
The calibration center of pitching balance inner core non-uniform beam is overlapped with the center of shaft, as measuring basis.
The maximum gauge of pitching balance outer wall is less than 51mm.
Sliding bearing uses copper master alloy inlaid solid lubrication bearing.
Compared with the prior art, the invention has the advantages that:
(1) the invention proposes unique dynamic pitching balance design thought, traditional tandem formula balance is breached
Design method reduces balance diameter so that dynamic scale overall volume is small, and inside and outside fabricated structure then shortens dynamic scale
Length, balance deformation is small, improves the rigidity and bearing capacity of dynamic scale.
(2) in technical solution of the present invention, dynamic scale calibration center is overlapped with shaft realization, improves dynamic scale measurement
Precision.
(3) strain beam can be dismounted independently in the present invention.Compared with the prior art, test accuracy of the invention is higher, dress
It is lower with difficulty.The thickness for only needing to change strain beam in the debugging process of ground carrys out Matching Model load, without repeating
Dismantle package unit, effective lifting test efficiency.The present invention can be widely applied in big load wind tunnel test balance test, tool
There are good practicability and promotional value.
Detailed description of the invention
Fig. 1 is the structural schematic diagram of five component dynamic pitching balances of the invention；
Fig. 2 is the cross-sectional view of Fig. 1；
Fig. 3 is the part composition schematic diagram of Fig. 1；
Fig. 4 is the dynamic scale structural schematic diagram under the prior art.
Specific embodiment
A specific embodiment of the invention is further described in detail with reference to the accompanying drawing.
The novel symmetrical aircraft in face is since normal load is big, vertically and horizontally load is mismatched and proposed to wind-tunnel dynamic scale technology
New requirement, and tunnel size limitation causes the dynamic scale to carry out Miniaturization Design.The invention proposes a kind of small-sized
Change five component dynamic pitching balance of big load integral type, be capable of providing effective transverse load output and improve normal direction load
Lotus bearing capacity, while measuring precision and also having obtained good raising.
As shown in Figure 1, Figure 2, Figure 3 shows, the invention proposes a kind of five component dynamic pitching days of miniaturized large-load integral type
It is flat, comprising: pitching balance inner core 1, pitching balance outer wall 2, shaft 3, strain beam 4, housing screw 5, sliding bearing 6.
Pitching balance inner core 1 includes head circular conical surface section, non-uniform beam, cooperation section and driving beam, and non-uniform beam is for surveying
Five component aerodynamic loadings are measured, cooperates and is provided with circular through hole and rectangular through-hole in section, pitching balance outer wall 2 is tubular structure, packet
Hollow cooperation section and tail portion circular conical surface section are included, is provided with circular through hole and rectangular through-hole in hollow cooperation section.
Pitching balance inner core 1 be arranged inside pitching balance outer wall 2,6 sets of sliding bearing outside shaft 3, and pass through bow
The circular through hole looked up to heaven on flat outer wall 2 and pitching balance inner core 1, by pitching balance outer wall 2 and the cooperation of pitching balance inner core 1 one
It rises, strain beam 4 passes through the rectangular through-hole on pitching balance outer wall 2 and pitching balance inner core 1, and rectangular configuration is for ensuring strain beam
4 can follow pitching balance inner core 1 to be moved completely, measure the corner of pitching balance inner core 1；Housing screw 5 will strain
Beam 4 and shaft 3 are fixed on pitching balance outer wall 2, the transverse direction for inhibiting strain beam 4 in motion process and shaft 3 to be subject to
Component.
The driving beam of pitching balance inner core 1 is located at the hollow cooperation intersegmental part of pitching balance outer wall 2, and hollow cooperation section
Internal diameter is greater than the maximum radial dimension of driving beam.It is hollow cooperation section internal diameter than driving beam maximum radial dimension greatly at least
10mm reserves enough spaces for the pitching simple harmonic motion of pitching balance inner core 1, avoids pitching balance inner core 1 in motion process
In collide with pitching balance outer wall 2.
3 rotation around the shaft of pitching balance inner core 1, rotational steps are pneumatic so as to more accurate acquisition not less than 1 °
The situation of change of load, is conducive to improving measurement accuracy.
The head circular conical surface section of pitching balance inner core 1 is 1:10 circular conical surface, and the tail portion circular conical surface section of pitching balance outer wall 2 is
1:10 circular conical surface.The contact area that can increase between component is attached using the circular conical surface of 1:10, make to connect it is even closer,
Reduce because being influenced caused by mechanical structure gap.
Be arranged on the driving beam tail end face of pitching balance inner core 1 it is fluted, for driving pitching balance inner core 1 around the shaft
3 rotations, realize pitching simple harmonic motion.
The non-uniform beam of pitching balance inner core 1 is stretch section, and maximum is respectively subjected to 10000N normal force and 120Nm pitching power
Square load；The range can satisfy the loading demands of the symmetrical aircraft in novel face, and it is enough rigid to guarantee that pitching balance inner core 1 has
Degree.
The calibration center of 1 non-uniform beam of pitching balance inner core is overlapped with the center of shaft 3, as measuring basis, is improved and is surveyed
Accuracy of measurement keeps structure more compact.
The maximum gauge of pitching balance outer wall 2 is less than 51mm, limits the overall volume of dynamic pitching balance；Therefore novel
The symmetrical lesser situation of aircraft test model in face can be completed to install, simultaneously because the small volume of dynamic pitching balance can also
To match other dynamic test models, can increase using range.
Sliding bearing 6 uses copper master alloy inlaid solid lubrication bearing, the bearing long service life, without later period addition profit
Lubrication prescription dismounts dynamic pitching balance within the service life time limit without repeating.
Working principle:
Be arranged on the driving beam tail end face of pitching balance inner core 1 it is fluted, with test supporting mechanism on eccentric cam
Connection, after the eccentric load provided by eccentric cam, the reciprocating motion in pitch orientation is converted to by groove.To drive
The whole pitching simple harmonic motion of pitching balance inner core 1, while band are realized in 3 rotation around the shaft of the driving beam of dynamic pitching balance inner core 1
Dynamic strain beam 4 synchronizes movement, measures the movement angle of pitching balance inner core 1.The head circular conical surface section of pitching balance inner core 1
Joint test model, the load change situation that the non-uniform beam measurement test model of pitching balance inner core 1 is subject in wind-tunnel.
Embodiment
As shown in figure 4, generalling use the dynamic of five COMPONENT BALANCEs and simple component hinge tandem form under the prior art
Pitching balance.Under 1.2 meters of magnitude wind-tunnel, the diameter of conventional five COMPONENT BALANCEs is generally 40mm, and miniaturization of the invention is big
The diameter of five component dynamic pitching balance of load integral type is then contracted to 36mm.The comparison of the two dimensional parameters is as follows:
Following table is under 1.2 meters of magnitude wind-tunnel, and conventional five COMPONENT BALANCEs are bowed with miniaturized large-load integral type five components dynamic
The range comparison for looking up to heaven flat.
Five component dynamic pitching balances significantly reduce compared to conventional five COMPONENT BALANCEs, axial dimension, while with straight
The reduction overall volume of diameter is also reduced, and more inner spaces is provided for test model, so as to the cloth of other measuring devices
It sets.In addition, the dynamic pitching balance of the present embodiment can carry bigger load, wherein the promotion of normal force is especially prominent, phase
Compared with conventional five COMPONENT BALANCEs, the present embodiment can be used for the dynamic test of the symmetrical aircraft in novel face.
Following table is the calibration accuracy index of the dynamic pitching balance of the present embodiment.
Had according to the dynamic pitching balance that upper table can be seen that the present embodiment extraordinary repeated and higher accurate
Degree.
By the structural model vibration shape to the present embodiment dynamic pitching balance and frequency meter point counting analysis, modal frequency compared with
Height shows its stiffness characteristics with higher, and dynamic pitching balance output voltage signal will have better periodicity, to protect
Demonstrate,proving measurement result has relatively higher precision.This point is verified in finite element dynamic simulation, which can be with
The effectively forced vibration signal of reproduction input, can complete accurately into forced row vibratory response.
Claims (10)
1. a kind of five component dynamic pitching balance of miniaturized large-load integral type, characterized by comprising: pitching balance inner core
(1), pitching balance outer wall (2), shaft (3), strain beam (4), housing screw (5), sliding bearing (6)；
Pitching balance inner core (1) includes head circular conical surface section, non-uniform beam, cooperation section and driving beam, and non-uniform beam is for measuring
Five component aerodynamic loadings cooperate and are provided with circular through hole and rectangular through-hole in section, and pitching balance outer wall (2) is tubular structure, packet
Hollow cooperation section and tail portion circular conical surface section are included, is provided with circular through hole and rectangular through-hole in hollow cooperation section；
Pitching balance inner core (1) setting is internal in pitching balance outer wall (2), and sliding bearing (6) is covered in shaft (3) outside, and is worn
The circular through hole on pitching balance outer wall (2) and pitching balance inner core (1) is crossed, it will be in pitching balance outer wall (2) and pitching balance
Core (1) is combined together, and strain beam (4) passes through the rectangular through-hole on pitching balance outer wall (2) and pitching balance inner core (1), is used
In the corner of measurement pitching balance inner core (1)；Strain beam (4) and shaft (3) are fixed on pitching balance outer wall by housing screw (5)
(2) on.
2. five component dynamic pitching balance of a kind of miniaturized large-load integral type according to claim 1, it is characterised in that:
The driving beam of pitching balance inner core (1) is located at the hollow cooperation intersegmental part of pitching balance outer wall (2), and the internal diameter of hollow cooperation section
Greater than the maximum radial dimension of driving beam.
3. five component dynamic pitching balance of a kind of miniaturized large-load integral type according to claim 2, it is characterised in that:
Maximum radial dimension greatly at least 10mm of the internal diameter of hollow cooperation section than driving beam.
4. five component dynamic pitching balance of a kind of miniaturized large-load integral type according to claim 1, it is characterised in that:
Pitching balance inner core (1) rotates around the shaft (3), and rotational steps are not less than 1 °.
5. five component dynamic pitching balance of a kind of miniaturized large-load integral type according to claim 1, it is characterised in that:
The head circular conical surface section of pitching balance inner core (1) is 1:10 circular conical surface, and the tail portion circular conical surface section of pitching balance outer wall (2) is 1:10
Circular conical surface.
6. five component dynamic pitching balance of a kind of miniaturized large-load integral type according to claim 1, it is characterised in that:
Be arranged on the driving beam tail end face of pitching balance inner core (1) it is fluted, for driving pitching balance inner core (1) (3) around the shaft
Pitching simple harmonic motion is realized in rotation.
7. five component dynamic pitching balance of a kind of miniaturized large-load integral type according to claim 1, it is characterised in that:
The non-uniform beam of pitching balance inner core (1) is stretch section, and maximum is respectively subjected to 10000N normal force and 120Nm pitching moment carries
Lotus.
8. five component dynamic pitching balance of a kind of miniaturized large-load integral type according to claim 1, it is characterised in that:
The calibration center of pitching balance inner core (1) non-uniform beam is overlapped with the center of shaft (3), as measuring basis.
9. five component dynamic pitching balance of a kind of miniaturized large-load integral type according to claim 1, it is characterised in that:
The maximum gauge of the pitching balance outer wall (2) is less than 51mm.
10. five component dynamic pitching balance of a kind of miniaturized large-load integral type according to claim 1, feature exist
In: sliding bearing (6) uses copper master alloy inlaid solid lubrication bearing.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201611195748.7A CN106840590B (en) | 2016-12-21 | 2016-12-21 | A kind of five component dynamic pitching balance of miniaturized large-load integral type |
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| CN201611195748.7A CN106840590B (en) | 2016-12-21 | 2016-12-21 | A kind of five component dynamic pitching balance of miniaturized large-load integral type |
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| CN106840590B true CN106840590B (en) | 2019-01-11 |
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Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108195555B (en) * | 2018-01-16 | 2019-09-24 | 中国空气动力研究与发展中心超高速空气动力研究所 | Optical fibre balance aerodynamics force measurement system and measurement method |
| CN108225720B (en) * | 2018-01-16 | 2023-05-12 | 中国空气动力研究与发展中心超高速空气动力研究所 | Optical fiber aerodynamic force measuring balance and optical fiber strain gauge mounting method |
| CN110940480B (en) * | 2019-11-13 | 2021-08-10 | 中国航天空气动力技术研究院 | Pitching yawing forced vibration dynamic derivative test device used under high attack angle of high-speed flying wing model |
| CN114061893A (en) * | 2021-12-28 | 2022-02-18 | 中国航天空气动力技术研究院 | Wind tunnel small-amplitude forced pitching oscillation mechanism |
| CN114152403B (en) * | 2022-02-08 | 2022-09-06 | 中国空气动力研究与发展中心超高速空气动力研究所 | High-precision pitching moment measuring device based on mechanical bearing |
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| CN204855125U (en) * | 2015-08-06 | 2015-12-09 | 无锡市羲和科技有限公司 | Measure device of three degree of freedom dynamic stability parameters in aircraft in high -speed wind tunnel |
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Patent Citations (6)
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|---|---|---|---|---|
| US4107986A (en) * | 1977-04-04 | 1978-08-22 | Mcdonnell Douglas Corporation | Five component strain gauge balance |
| CN101183039A (en) * | 2007-11-30 | 2008-05-21 | 中国航天空气动力技术研究院 | Balance system with inhibition structure |
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