CN208076551U - A kind of mechanical filter applied to high G-value jerk acceleration transducer - Google Patents
A kind of mechanical filter applied to high G-value jerk acceleration transducer Download PDFInfo
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- CN208076551U CN208076551U CN201820533655.9U CN201820533655U CN208076551U CN 208076551 U CN208076551 U CN 208076551U CN 201820533655 U CN201820533655 U CN 201820533655U CN 208076551 U CN208076551 U CN 208076551U
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- Prior art keywords
- mechanical filter
- acceleration transducer
- gasket
- sensor
- pedestal
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Abstract
A kind of mechanical filter applied to high G-value jerk acceleration transducer finely tunes rigidity and the damping of damping material by external prestress so that there is best performance in mechanical filter pole.The mechanical filter includes pedestal, isolation structure, bottom filtering gasket, top filtering gasket and top briquetting, the isolation structure includes bottom isolation pad, lateral confinement structure and top isolation pad three parts, mechanical filter can effectively inhibit shock transducer high-frequency vibration ingredient so that when bearing high G-value impact needle position misalignment does not occur for sensor.Mechanical filter is designed to isolated form, is capable of the electrical connection attribute of isolation sensor core and sensor outer housing, and shell interference signal is effectively avoided to influence sensor output.
Description
Technical field
The utility model is related to a kind of mechanical filters applied to high G-value jerk acceleration transducer, and in particular to one
Kind can inhibit high fdrequency component of the sensor when bearing high G-value impact, can effectively inhibit shock transducer output baseline drift
Move the mechanical filter of phenomenon.
Background technology
A major class of the piezoelectricity high G accelerometer as high G-value acceleration, easy tos produce when bearing HI high impact
Needle position misalignment.Baseline is not on zero curve in impact process, but has a DC component on zero curve.It is learnt by analysis, by
In high G accelerometer when absorbing impact, high fdrequency component causes the sensitive core body of piezoelectric transducer to generate lasting charge.
The signal output-response that high frequency response generates shows as baseline not back to zero to sensor output.Back to zero is not direct for sensor base line
High G accelerometer acceleration measurement accuracy is influenced, leading to measurement, there are large errors.In examination high G-value
The occasion of shock frequency spectrum characteristic, baseline not back to zero frequency domain representation be low-frequency spectra distortion.Low-frequency spectra is distorted so that test examination
The low frequency characteristic of test can not be obtained by testing, and influence the experiment effect of high G-value shock measurement.In order to inhibit high G-value acceleration sensing
Device does not generate needle position misalignment when bearing HI high impact, and effectively filtering out high fdrequency component becomes the important hand for solving baseline not back to zero
Section.
Utility model content
The purpose of this utility model is to provide a kind of solution piezoelectric type high G accelerometer baseline not zero resetting devices
That is mechanical filter improves high G-value and adds for filtering out impact class acceleration transducer radio-frequency component when bearing high G-value impact
Velocity sensor impact property.
The utility model proposes a kind of mechanical filter applied to high G-value jerk acceleration transducer, machinery filters
Wave device includes that pedestal, isolation structure, bottom filtering gasket, top filtering gasket and top briquetting, the isolation structure include bottom
Portion's isolation pad, lateral confinement structure and top isolation pad three parts;The bottom isolation pad, bottom filtering gasket, cross
It is sequentially loaded into the pedestal to restraining structure, top filtering gasket, top isolation pad and top briquetting, is pressed by the top
The pretightning force that block applies tightens together above-mentioned all building blocks to form the mechanical filter, and the pedestal includes installation
Stud, hexagonal structure, barrel-like structure, installation screw thread, inboard mounting surface and bottom mounting surfaces, the top briquetting include briquetting bottom
Face, installation screw thread and loading structure.
Preferably, integrated screw rod is processed on the pedestal, for being spirally connected with external mounting surface.
Preferably, the pedestal is barrel-like structure, to place other all mechanical filter building blocks.
Preferably, the pedestal top is provided with installation screw thread, for being coordinated to mechanical filter with top briquetting
And sensor core applies pretightning force.
Preferably, the isolation structure uses polyimide material.
Preferably, it is damping material that the bottom filtering gasket, which uses circular configuration, material,.
Preferably, the thickness of the bottom filtering gasket is 1mm.
Preferably, the top filtering gasket is the circular configuration of middle with hole, and material filters gasket with the bottom
It is identical.
Preferably, the lateral confinement structure uses barrel-like structure, using polyimide material, wall thickness 0.5mm.
Realize the technical solution of the utility model:A kind of mechanical filter using high G-value jerk acceleration transducer, packet
Include the filter gasket for sensor core top and the filter gasket of sensor core bottom end.Upper layer and lower layer filter pad
Piece forms the core of mechanical filter.
The mechanical filter of the utility model design, the structural strength that mechanical filter is combined with accelerometer are wanted to hold
It is impacted by high G-value, many simple Vibration Absorbing System Designs are disintegrated under HI high impact.
The Q values of the mechanical filter of the utility model design want very low, to ensure sensor in wider frequency range
It is interior to keep linear.The cooperation damping characteristic of mechanical filter and sensor must emphasis consideration.
Displacement between the non-sensitive part and installation surface of the sensor of the utility model design is no more than filter
The range of linearity.When the range of linearity beyond filter, mechanical filter will not have high-frequency signal filtering characteristic, sensor will
Losing the protection of filter influences its output characteristics.
The transmission characteristic of the utility model mechanical filter must clearly define, and the result of transmission characteristic, which must have, to be repeated
Property.
The utility model mechanical filter uses incorporating filter structure, with high-performance mechanical filter material by sensor
Sensitive core body surrounds be placed in inside sensor outer housing completely.Sensor all directions have filtering characteristic.The utility model uses
Filter material have higher intensity simultaneously and have certain damping characteristic.
The mechanical filter of the utility model design approximate can regard the system that spring is constituted with mass block as, approximate with two
Rank system model characterizes its response characteristic, shown in typical form universal model Fig. 9.As shown in Figure 9, by the one of spring and damper
End is separately fixed at reference coordinate and fastens, and assumes that input signal is applied directly on mass block.In Fig. 9, c indicates damping system
Number, k indicate that stiffness coefficient, m indicate mass block quality, b0X indicates that system institute excited target, y indicate the relative displacement that system generates.
The mathematic(al) representation of the model is as shown in Equation 3,
Wherein, a2=m, a1=c, a0=k.
Enable static sensitivityDamping ratioUndamped natural angular frequencyThen
It is as follows frequency response function can be obtained
Amplitude versus frequency characte is as follows
Damping characteristic curve is drawn according to formula (4), determines that mechanical filter damps by the damping characteristic curve of drafting
And rigidity.
Material stiffness and damping have been adjusted to optimum state by the utility model using special filtering material, ensure to use
The sensor of the utility model has preferable frequency response characteristic and preferable high-frequency suppressing characteristic.
The utility model mechanical filter is combined mode using top layer bottom filter and realizes mechanical filtering, can be effective
It filters out axial high fdrequency component and inhibits sensor output signal needle position misalignment.
The utility model devises corresponding isolated material other than filtering material, and isolated material is mainly used for sensor core
Body is isolated with shell, and sensor outer housing interference signal is avoided to introduce sensor output.
The utility model uses top outlet method, and top is using filter material and isolated material combination.Filtering
Material forms high-frequency suppressing effect by the damping of itself and rigidity, and isolated material isolation core avoids sensor from exporting with shell
Be connected introducing interference with shell.Filtering material and isolated material will be designed to the disc structure of middle with hole by the utility model,
Interstitial hole is used for outlet.
The mechanical filter of the utility model design needs to apply precompressed force effect to briquetting, and the effect of briquette structure is main
For applying external prestress, sensor core and filtering material isolated material are pressed together and improve sensor rigidity.Pressure
Block active force makes filtering material reach best filter state, and briquetting prestress value is determined by repetition test, will filter material
Material filtering performance performs to optimum state.
The utility model is suitable for the piezoelectric impact sensor with molding sensitive core body, is changed by mechanical filter effect
Kind sensitive core body output characteristics inhibits needle position misalignment phenomenon.Isolated material is placed in pedestal bottommost filtering material and is placed in isolation material
On material, avoid, since insulation characterisitic reduces after filtering material stress, sensitive core body being caused to introduce external disturbance with base contacts.
Sensitive core body is placed on filtering material, filtering material is assembled at the top of sensitive core body and isolated material is placed in top filtering material
On material.Top isolated material forms pressing relationship with top briquetting, and the filtering of sensitive core body machinery is combined into after the completion of assembly
Device.
The utility model avoids generating lateral position when bearing high G-value impact due to sensor using lateral confinement structure
It moves, leads to the component of acceleration outside sensor output amount of production.Lateral confinement structure is installed to sensitive core body outer surface, is sensing
It is fitted into sensor outer housing together with core when device integrally assembles.
The advantageous effect of the utility model compared to the prior art is:
1) mechanical filter of the utility model can help to solve conventional piezoelectric sensor when bearing high G-value impact
The cheap problem of baseline;
2) mechanical filter of the utility model can effectively filter out the high-frequency percussion suffered by sensor core, effectively protect
Protect sensor core;
3) the utility model uses isolation structure, overcomes conventional piezoelectric sensor and exports the influence that is connected with sensor outer housing
The deficiency of sensor output.Filter makes sensor core be isolated with shell electric appliance, avoids sensor core output by outer
Shell influences.
Description of the drawings
Fig. 1 is the cross-sectional view of the mechanical filter of the utility model embodiment jerk acceleration transducer;
Fig. 2 is the cross-sectional view of the utility model embodiment mechanical filter building block pedestal;
Fig. 3 is the isolation pad structure schematic diagram of the utility model embodiment mechanical filter building block bottom surface;
Fig. 4 is the filtering gasket construction schematic diagram of the utility model embodiment mechanical filter building block bottom surface;
Fig. 5 is the structural schematic diagram of the utility model embodiment mechanical filter building block lateral confinement structure;
Fig. 6 is the structural schematic diagram of the utility model embodiment mechanical filter building block top surface filtering gasket;
Fig. 7 is the structural schematic diagram of the utility model embodiment mechanical filter building block top surface isolation pad;
Fig. 8 is the structural schematic diagram of briquetting at the top of the top surface of the utility model embodiment;
Fig. 9 is the damper model schematic diagram of the utility model embodiment.
Wherein, the reference numerals are as follows:Pedestal 1, bottom surface isolation pad 2, bottom surface filtering gasket 3, lateral confinement structure
4, top surface filtering gasket 5, top surface isolation pad 6, top briquetting 7, installation stud 11, hexagonal structure 12, barrel-like structure 13, installation
Screw thread 14, inboard mounting surface 15, bottom mounting surfaces 16, briquetting bottom surface 71, installation screw thread 72, loading structure 73.
Specific implementation mode
The implementation of the utility model is further detailed below in conjunction with attached drawing.It, below will be detailed referring to Fig. 1-Fig. 9
The feature and exemplary embodiment of the various aspects of the utility model are described.Each side of the utility model is described more fully below
The feature and exemplary embodiment in face.In the following detailed description, it is proposed that many details, in order to provide to this practicality
Novel comprehensive understanding.The utility model is related to a kind of novel mechanical filter constructions, in order to preferably be described, in conjunction with figure
Specific implementation mode is described.Shown in Fig. 1~Fig. 8, the utility model proposes a kind of machines applied to HI high impact sensor
Tool filter designs, and includes mainly pedestal 1, bottom surface isolation pad 2, bottom surface filtering gasket 3, lateral confinement structure 4, top surface filtering
Gasket 5, top surface isolation pad 6, top briquetting 7.All structures form mechanical filter knot by being sequentially completed successively
Structure.Damping and stiffness combine of the mechanical filter by filtering material filter out shock transducer high frequency when absorbing impact and believe
Number.
The structure in conjunction with shown in Fig. 1 describes total assembling process.Bottom surface isolation pad 2 is positioned over pedestal bottom first
Portion, must be smooth when bottom surface isolation pad 2 is placed, and destruction is generated to power gasket when the later stage being avoided to install.Bottom surface is isolated
Gasket 2, which is placed, completes to place filtering gasket 3 in bottom surface on bottom surface isolation pad 2 later, and bottom surface filtering gasket 3 relies primarily on itself
Damping and rigidity generate filtering characteristic.Bottom surface filters 3 bottom surface of gasket and forms fitting surface, bottom surface filter with 2 top surface of bottom surface isolation pad
3 top surface of wave gasket forms fitting surface with sensor core bottom surface.Bottom surface filtering gasket 3 is made of damping material, material property
With certain pliability, assembly when, must ensure that bottom surface filtering gasket 3 is smooth.Bottom surface isolation pad 2, bottom surface filter gasket
After the completion of 3 assembly, lateral confinement structure 4 is assembled to sensor chip side wall.4 top edge of lateral confinement structure and sensor
Core top edge is concordant, and lateral confinement structure 4 must wrap sensor sensing core well, can be in lateral side
Ensure isolated relation between sensor core and pedestal upwards.Lateral confinement structure 4 assemble after the completion of, by sensor core together with
Lateral confinement structure 4 is assembled in pedestal.Since lateral confinement structure 4 acts on, sensor sensing core and lateral confinement structure 4
Matching relationship is tight fit between pedestal 1 after assembly completion, and tight fit can effectively inhibit sensor core bearing high G
Value generates lateral displacement when impacting.Sensor core is installed to pedestal, the filtering material at the top of sensors topside assembly
5, there is terminal with sensitive core body and forms assembly relation in filtering material 5 center mounting hole in top surface.5 bottom surface of top surface filtering material with it is quick
Feel core top surface and form fitting surface, the assembly of top surface filtering material 5 assembles top surface isolation pad 6, top surface isolation pad 6 after completing
There is terminal with sensitive core body and forms assembly relation in center mounting hole.Isolation pad 6 upper surface in top surface forms with 7 bottom surface of briquetting and fills
With face, the assembly of top surface isolation pad 6 installs briquetting 7 after completing.Briquetting 7 is by Screw assembly to pedestal 1, assembling briquetting
Applied pre-fastening moment is measured when 7 by torque spanner, filtering material rigidity and resistance are changed by control moment size
Buddhist nun.
Fig. 2 is mechanical filter pedestal 1, and pedestal is by installation stud 11, hexagonal structure 12, barrel-like structure 13, installation screw thread
14, inboard mounting surface 15, bottom mounting surfaces 16.Installation 11 structure of stud is mainly used for sensor and is installed with external mounting surface, and one
Bodyization installation stud 11 simplifies structure, improves the rigidity of structure.The rigidity of simplified structure and reinforcing is bearing high G-value impact
When it is most important, disclosure satisfy that structure be unlikely to when high G-value impacts generate destruction.1 inboard mounting surface 15 of pedestal is directly
Assembly relation is formed with bottom surface isolated material 2, pedestal acceleration is passed to by sensing by power transfer mode when in use
Device sensitive core body.1 inside installation bottom surface 15 of pedestal needs higher flatness, avoids causing since flatness does not reach requirement
Mechanical filter structural failure.1 bottom mounting surfaces 16 of pedestal are also required to higher flatness, to coordinate with external mounting surface.
It needs to keep the higher depth of parallelism, the high depth of parallelism that can ensure in an axial direction between inside installation bottom surface 15 and bottom mounting surfaces 16
Impact not will produce other components of acceleration and then improve measurement accuracy.13 structure of barrel-like structure is primarily used to form outside sensor
Shell protects sensor core not by external damage.Devised on barrel-like structure 13 installation screw thread 14, installation screw thread 14 mainly with pressure
Block 7 installs screw thread 72 and forms assembly relation.Briquetting 7 forces tight mechanical filter structure by installing the offer of screw thread 14 when assembly,
Installation screw thread generation is tried hard to keep enough demonstrate,proves mechanical filter intensity, it is made to be unlikely to generate destruction when bearing high G-value impact.
Fig. 3 is bottom surface isolation pad 2, and ground isolation pad is needed by sufficient intensity, higher insulation characterisitic.Bottom surface is isolated
Gasket 2 uses high-strength insulating material machine-shaping.2 sufficient intensity of bottom surface isolation pad and minimum damping, avoid the bottom of due to
The change of 2 material property of face isolation pad can not debug bottom surface filtering 3 material property of gasket.
Fig. 4 is that bottom surface filters gasket 3, and bottom surface filters gasket 3 and is used as the most crucial component of mechanical filter, to its material property
It is required that extremely harsh.Filtering material belongs to damping material, material property in addition to other than by itself affect also with suffered external force phase
It closes.After type selecting filtering material, need to determine pretightning force suffered by filtering material by repetition test, it is final so that filtering material
Material reaches optimum performance.Filtering material damping characteristic can influence sensor linearity to a certain extent, therefore select filtering
Influence of the material to the sensor core linearity must be controlled when material.Bottom surface filters gasket 3 using simplified round knot
Structure, thickness are determined as 1mm by repetition test, the utility model type selecting material by various experiments, determine 1mm thickness
To meeting sensor High frequency filter demand, and ensure that sensor linearity is not influenced by filtering material.
Fig. 5 is lateral confinement structure 4, and lateral confinement structure 4 is designed to that garden barreled is assembled with sensor core outer wall.
Lateral confinement structure 4 is assembled with pedestal 1 again after being assembled with sensor core, lateral confinement structure 4 and the sensor core bodily form
At assembly and shell be necessary for tight fit relationship, avoid generating lateral displacement when absorbing impact.
The top surfaces Fig. 6 filtering gasket 5 is designed to the structure of middle with hole, and interstitial hole effect is to be used for assembly sensor outlet
Terminal.Top surface filters the filtering material identical as bottom surface filtering 3 use of gasket of gasket 5, is to meet using top surface filtering gasket 5
Mechanical filter symmetric row makees filtering gasket 5 to thicken processing guarantee mechanical filter up-down symmetry.
Fig. 7 is top surface isolation pad 6, and top surface isolation pad 6 designs main function isolation sensor core and shell is electrical
Connection performance avoids because shell has an impact sensor output.Another effect of top surface isolation pad 6 is used as filtering
Material is isolated with top briquetting 7, and since filtering material is damping material, briquetting is in direct contact filtering material and is applying pretightning force
When most likely result in the destruction of filtering material.
Fig. 8 is top briquetting 7, and briquetting 7 structure in top includes mainly briquetting bottom surface 71, installation screw thread 72, loading structure 73.
Briquetting 7 structure briquetting bottom surface 71 in top needs enough flatness, avoids occurring bias when assembly and cannot achieve and 1 spiral shell of pedestal
Line assembles.Installation screw thread 72 needs to ensure sufficient intensity, and installation screw thread 72 is mainly for generation of pretightning force, and enough pretightning forces are
It can guarantee sensor intensity.73 main function of loading structure is for loading, torque spanner being facilitated to be clamped.
The content not being described in detail in the utility model specification belongs to existing well known to professional and technical personnel in the field
Technology.Above-described embodiment of the utility model is to cannot be used for limitation the utility model to the explanation of scheme, new with this practicality
Type has any change in the comparable meaning and scope of protection domain, is all considered as being included in the range of the utility model protection
It is interior.
Claims (9)
1. a kind of mechanical filter applied to high G-value jerk acceleration transducer, it is characterised in that:The mechanical filter includes
Pedestal (1), isolation structure, bottom filtering gasket (3), top filtering gasket (5) and top briquetting (7), the isolation structure packet
Include bottom isolation pad (2), lateral confinement structure (4) and top isolation pad (6) three parts;The bottom isolation pad (2),
Bottom filters gasket (3), lateral confinement structure (4), top filtering gasket (5), top isolation pad (6) and top briquetting (7)
It is sequentially loaded into the pedestal (1), above-mentioned all building blocks are fastened on one by the pretightning force applied by the top briquetting (7)
It rises and forms the mechanical filter, the pedestal (1) includes installation stud (11), hexagonal structure (12), barrel-like structure (13), peace
Screw thread (14), inboard mounting surface (15) and bottom mounting surfaces (16) are filled, the top briquetting (7) includes briquetting bottom surface (71), peace
Fill screw thread (72) and loading structure (73).
2. according to a kind of mechanical filter applied to high G-value jerk acceleration transducer described in claim 1, feature
It is:Integrated screw rod is processed on the pedestal (1), for being spirally connected with external mounting surface.
3. according to a kind of mechanical filter applied to high G-value jerk acceleration transducer described in claim 1, feature
It is:The pedestal (1) is barrel-like structure, to place other all mechanical filter building blocks.
4. according to a kind of mechanical filter applied to high G-value jerk acceleration transducer described in claim 1, feature
It is:Pedestal (1) top is provided with installation screw thread (14), for being coordinated to mechanical filter with top briquetting (7)
And sensor core applies pretightning force.
5. a kind of mechanical filter applied to high G-value jerk acceleration transducer according to claim 1, feature exist
In:The isolation structure uses polyimide material.
6. a kind of mechanical filter applied to high G-value jerk acceleration transducer according to claim 1, feature exist
In:It is damping material that the bottom filtering gasket (3), which uses circular configuration, material,.
7. a kind of mechanical filter applied to high G-value jerk acceleration transducer according to claim 1, feature exist
In:The thickness of the bottom filtering gasket (3) is 1mm.
8. a kind of mechanical filter applied to high G-value jerk acceleration transducer according to claim 1, feature exist
In:The top filtering gasket (5) is the circular configuration of middle with hole, and material is identical as bottom filtering gasket (3).
9. a kind of mechanical filter applied to high G-value jerk acceleration transducer according to claim 1, feature exist
In:The lateral confinement structure (4) uses barrel-like structure, using polyimide material, wall thickness 0.5mm.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
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CN201820533655.9U CN208076551U (en) | 2018-04-13 | 2018-04-13 | A kind of mechanical filter applied to high G-value jerk acceleration transducer |
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CN201820533655.9U CN208076551U (en) | 2018-04-13 | 2018-04-13 | A kind of mechanical filter applied to high G-value jerk acceleration transducer |
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Publication Number | Publication Date |
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CN208076551U true CN208076551U (en) | 2018-11-09 |
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CN201820533655.9U Expired - Fee Related CN208076551U (en) | 2018-04-13 | 2018-04-13 | A kind of mechanical filter applied to high G-value jerk acceleration transducer |
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2018
- 2018-04-13 CN CN201820533655.9U patent/CN208076551U/en not_active Expired - Fee Related
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GR01 | Patent grant | ||
CF01 | Termination of patent right due to non-payment of annual fee | ||
CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20181109 Termination date: 20190413 |