CN203616051U - Sensor checking system - Google Patents
Sensor checking system Download PDFInfo
- Publication number
- CN203616051U CN203616051U CN201320665000.4U CN201320665000U CN203616051U CN 203616051 U CN203616051 U CN 203616051U CN 201320665000 U CN201320665000 U CN 201320665000U CN 203616051 U CN203616051 U CN 203616051U
- Authority
- CN
- China
- Prior art keywords
- sensor
- hydraulic
- tested
- checking system
- data processor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Abstract
The utility model relates to a sensor checking system. The sensor checking system comprises a hydraulic force application system, a standard sensor, a sensor to be checked, a data collector and a data processor. The hydraulic force application system comprises at least one stand column, a fixing device and a hydraulic device, wherein a lower beam is connected with the first end of the stand column, an upper beam is connected with the second end of the stand column, and the two sensors are connected with the data processor through the data collector. The checking system is simple in structure, tension force or pressure needed in checking is provided by the hydraulic force application system and the structure is lighter. Thus, on-site checking at the position of equipment of a client can be achieved, use is convenient, and time and transportation cost can be saved.
Description
Technical field
The utility model relates to instrument testing technical field, particularly relates to a kind of sensor checking system.
Background technology
The check of the gauging instrument of power and power sensor and calibration are generally carried out in Bureau of Technical Supervision or metering institute, and main means of testing is gravity weight type method of inspection.Inspection principle is to apply the weight counterweight in range ability to power sensor, and the reading of the weight to counterweight and power sensor contrasts, and whether error of calculation determine sensor is qualified.The power sensor of wide range needs user's removal force sensor to deliver to the check of metering institute, the long use that has delayed user's instrument and equipment of round of visits.
The weight metering counterweight of metering institute is comparatively accurate, and the counterweight of counterweight promotes and marshalling is applied with the device of a set of complexity, goes field test so can not carry tons of metering counterweights.Metering gravity sensor needs regular forced examination, and client's censorship power sensor can be paid larger time and transportation cost to metering institutes so, and client's instrument and equipment is stopped transport and also can be caused very large loss simultaneously.
Utility model content
Provide hereinafter about brief overview of the present utility model, to the basic comprehension about some aspect of the present utility model is provided.Should be appreciated that this general introduction is not about exhaustive general introduction of the present utility model.It is not that intention is determined key of the present utility model or pith, neither be intended to limit scope of the present utility model.Its object is only that the form of simplifying provides some concept, using this as the preorder in greater detail of discussing after a while.
A fundamental purpose of the present utility model is to provide a kind of sensor checking system simple in structure, easy to use.
To achieve these goals, the utility model provides a kind of sensor checking system, comprising: hydraulic amplifier system, standard transducer, sensor to be tested, data acquisition unit and data processor; Described hydraulic amplifier system comprises: at least one column; Underbeam, is fixedly connected on the first end of described column; Upper beam, is arranged at the second end of described column, and parallel with described underbeam; And stationary installation, for being longitudinally coaxially series at described standard transducer and described sensor to be tested between described upper beam and underbeam; Hydraulic means, is arranged on described underbeam, for described standard transducer and to be tested are applied to pulling force or pressure; Described standard transducer is connected with described data processor through described data acquisition unit respectively with described sensor to be tested.
Than prior art, the beneficial effects of the utility model are:
Sensor checking system of the present utility model is simple in structure, and while using hydraulic amplifier system that check is provided, needed pulling force or pressure, do not need additionally to use counterweight, and the utility model sensor checking system structure is more light.Make sensor checking system of the present utility model can arrive the field test of customer equipment place, easy to use, have compared with traditional check system more can save time, the advantage such as traffic cost.
Accompanying drawing explanation
With reference to the explanation to the utility model embodiment below in conjunction with accompanying drawing, can understand more easily above and other objects, features and advantages of the present utility model.Parts in accompanying drawing are just in order to illustrate principle of the present utility model.In the accompanying drawings, same or similar technical characterictic or parts will adopt same or similar Reference numeral to represent.
Fig. 1 is the annexation figure of the utility model sensor checking system.
Fig. 2 is the one-piece construction schematic diagram of the utility model sensor checking system.
Fig. 3 is the schematic diagram of hydraulic amplifier system in the utility model sensor checking system.
Fig. 4 is the process flow diagram of the utility model sensor method of inspection.
Embodiment
Embodiment of the present utility model is described with reference to the accompanying drawings.The element of describing in an accompanying drawing of the present utility model or a kind of embodiment and feature can combine with element and feature shown in one or more other accompanying drawing or embodiment.It should be noted that for purposes of clarity, in accompanying drawing and explanation, omitted with the utility model irrelevant, expression and the description of parts known to persons of ordinary skill in the art and processing.
Referring to Fig. 1, a kind of sensor checking system, comprising: hydraulic amplifier system 1, standard transducer 3, sensor to be tested 2, data acquisition unit and data processor 14.Data acquisition unit is connected standard transducer 3, sensor to be tested 2 respectively with data processor.Wherein, referring to Fig. 2, hydraulic amplifier system 1 comprises column 12, underbeam 13, upper beam 11, stationary installation and hydraulic means.The quantity of column is at least one, and upper beam 11 and underbeam 13 are connected to the two ends of column, and underbeam is fixedly connected with column, and upper beam 11 and underbeam 13 parallel to each other; Stationary installation is for being longitudinally coaxially series at standard transducer 3 and sensor to be tested 2 between described upper beam 11 and underbeam 13; Hydraulic means is for applying pulling force or pressure to above-mentioned standard transducer 3 and sensor to be tested 2.
Sensor checking system of the present utility model is simple in structure, and while using hydraulic amplifier system 1 that check is provided, needed pulling force or pressure, do not need additionally to use counterweight, and one-piece construction is more light.
Further, in order to guarantee to treat the accuracy that test sensors 2 is checked, the measuring accuracy grade of standard transducer 3 is higher than the measuring accuracy grade of described sensor 2 to be tested.Certainly, in checkout procedure, sensor, by Power supply, optionally provides constant voltage or Constant Electric Current by least one programmable power supply 15 for sensor 2 to be tested.Concrete, standard transducer 3 and sensor to be tested 2 all need Power supply, and standard transducer 3 can be the sensor of certain type of having selected, according to this type of having selected, configure corresponding power supply, sensor 2 to be tested is not what to have selected, may be various types of sensors, this just exists some sensors to need constant voltage power supply, some need constant current-supplying, therefore, sensor checking system of the present utility model adopts programmable power supply, and the electricity of constant voltage or constant current is provided according to the demand of difference sensor 2 to be tested.In addition, the unfavorable factor such as ripple, noise occurring when Power supply has impact to sensor, so can adopt programmable power supply to reduce or avoid these unfavorable factors.
Continue referring to Fig. 1, alternatively, above-mentioned data collector comprises the first digital multimeter 16 and the second digital multimeter 17, these two multimeters are connected to data processor by standard transducer 3 with sensor 2 to be tested respectively and are connected, two multimeters gather respectively the measurement data of your sensor of mark and sensor to be tested 2, and send to data processor.In optional embodiment, the first digital multimeter 16 and the second digital multimeter 17 adopt six Semi-digital multimeters, and are connected with data processor by USB interface; Data processor can be computing machine.This connected mode is simple, is easy to connect.
Referring to Fig. 2 and 3, in one embodiment, hydraulic means comprises: hydraulic cylinder 9, is fixedly installed on described underbeam 13; Hydraulic arm moves upward in the side that is parallel to column; The size of the acting force that hydraulic pump adjustment applies to the interior liquid of hydraulic cylinder 9; Reversal valve 6, is connected with described hydraulic pump and described hydraulic cylinder 9, for changing the direction of the acting force that hydraulic pump applies to the interior liquid of described hydraulic cylinder 9.In use procedure, hydraulic means applies power by hydraulic arm to standard transducer 3 and sensor to be tested 2, and adjust the size of the power that applies by hydraulic pump 5, certainly, by the reversal valve 6 being connected with hydraulic pump 5 and hydraulic cylinder 9 respectively, change the side of the acting force that applies to the interior liquid of described hydraulic cylinder 9 of hydraulic pump 5, adjusting the power that hydraulic arm applies standard transducer 3 and sensor to be tested 2 is pressure or pulling force.Above-mentioned preferably hydraulic hand-pump of hydraulic pump 5.Should be appreciated that, what no matter apply is pressure or pulling force, and standard transducer 3 and sensor to be tested 2 are all connected between upper beam 11 and underbeam 13 under the effect of stationary installation.And, the utility model preferably uses hydraulic hand-pump, assurance applies the size of power can be constant, and can confirm intuitively the size of the power that applies, certainly, this just preferred embodiment, the hydraulic pump of other types goes for the utility model equally, as electric hydraulic pump, but using when electric hydraulic pump, avoid as far as possible the unstable of the power that causes as reasons such as change in voltage.
Further, sensor checking system also wrap there is holding area draw together base 4, hydraulic amplifier system 1, is arranged at described base 4 tops, described data processor is arranged in described holding area.In the optional embodiment of one, on base 4, be provided with drawer 7, hold the screen (for example, in the time that data processor is computing machine, the screen of mentioning is display, and this display can be touch-screen, uses with handled easily) being connected with data processor here.This sentences touch-screen is example, for artificial input instruction or control signal, for example, starts, stops check; Preferred, the touch-screen here can be structure as a whole with above-mentioned data processor, as touch control integratedization computing machine.Should be appreciated that, the drawer is here caught up with the accommodation space of stating base 4 and is not conflicted, and they can be same members, can be also different, and for example, in the time that touch-screen and data processor are touch control integratedization computing machine, the accommodation space of base 4 can be drawer.When touch-screen and data processor are Split type structure, while connecting transmission of signal by data line, accommodation space and drawer can not be a member, and data processor is received within accommodation space, and touch-screen is put into drawer, expose with respect to base 4 with the pull of drawer.
More specifically, in a preferred embodiment, column 12 quantity are multiple, the all settings parallel to each other of these columns, on the reference field perpendicular to column 12 axle center, by the projection on reference field of each column, on reference field, the geometric center region of projection of shape, arranges above-mentioned stationary installation.Should be appreciated that, here the institute of stationary installation will be arranged on above-mentioned geometric center, because in use, stationary installation will be fixed on standard transducer 3 and sensor to be tested 2 between upper beam 11 and underbeam 13, and apply power by hydraulic means, and upper beam 11 and underbeam 13 are all arranged on column 12, therefore column 12 will have enough rigidity, and follow column have time more, guarantee the stressed identical of each column, to avoid stressed difference to cause column deformation, this can cause the direction of the power that standard transducer 3 and sensor to be tested 2 are applied to change, thereby the check work of impact to power sensor.For example, in the time that column 12 is two, these two columns are parallel to each other, take the face in the axle center of vertical pillars 12 as reference field, this two columns 12 projection on reference field (for convenience of description, relate to " projection " below and all represent that face take the axle center of vertical pillars 12 is as reference field, the projection of column 12 on reference field) be straight line, stationary installation is just arranged on the center (geometric center region) of this straight line so.While being three as column 12 numbers, according to above-mentioned, it is projected as triangle at reference field, and stationary installation is just arranged on leg-of-mutton center of gravity place so.The position that multiple columns arrange, preferably meets and makes above-mentioned projection form regular polygon, during as three columns 12, is projected as equilateral triangle; When five columns 12, be projected as regular pentagon.Certainly, should be appreciated that, the position that above-mentioned stationary installation arranges, in order to guarantee the stressed even of column 12, guarantee that the stressed direction that do not occur of standard transducer 3 and sensor to be tested 2 is offset, and makes the two stressed identical, to avoid being subject to force direction difference because of the two, the error producing, thus the precision of verification improved.
Further, above-mentioned stationary installation comprises: support portion, parallel with column 12, support portion is disposed with the first and second installation portions from bottom to top, respectively fixed standard sensor 3 and sensor to be tested 2.Certainly, this is a kind of preferred embodiment, and fixing order is not certain, and the first installation portion can fixed standard sensor 3, equally also can fix sensor 2 to be tested.In one preferred embodiment, the first installation portion is arranged on hydraulic means, and the second installation portion is arranged on upper beam 11, and two installation portions are also coaxial toward each other, and hydraulic means is exerted pressure to standard transducer 3 and sensor to be tested 2 by the second installation portion.Here the position of the first installation portion and the second installation portion setting is a kind of optimal way, as long as can fixed standard sensor 3 and sensor to be tested 2, and it be identical applicable to the utility model to guarantee that the two is subject to the power that hydraulic means applies.
In a kind of preferred embodiment, the position of upper beam 11 is arranged at one end of column adjustablely, and what it can parallel column 12 moves axially, and meets the sensor to be tested 2 of different size is tested with this.In order to coordinate the position of above-mentioned upper beam 11 adjustable, on column 12, be provided with the locating device that upper beam 11 is positioned, comprising: set nut 10 and adjustment ring 8, after upper beam 11 is adjusted to the right place, by set nut 10 and adjustment ring 8, it is fixed.Particularly, set nut 10 is arranged at a upper beam side of underbeam dorsad, is threaded with column; Adjustment ring 8, is arranged at the side of upper beam 11 towards underbeam 13, and is threaded with described column.Also can be two locknuts that are threaded with column 12, upper beam 11 chucks, between two locknuts, have been completed to the location to upper beam 11.Certainly, this is preferred embodiment, can guarantee that upper beam 11 can adjust position on column 12, can equally can be for the utility model by its firm other forms of locating device being fixed on column 12 after adjusting to the right place.
Certainly, for convenient, sensor checking system of the present utility model is brought to the field test of customer equipment place, further, on base 4, can also be provided with handle, and/or leveller; Handle uses while being used for mobile described sensor checking system, it can be any type of handle, as be parallel to base 4 upper surfaces, and be installed on the cylindrical bar on base 4 by support, or be arranged on the bowhandle on base 4 sidewalls, as long as can realize, sensor checking system moved and can be used in the utility model.Certainly,, for sensor checking system can move more easily, base 4 belows can also arrange roller.In addition, on base 4, be also provided with leveller, for the leveling to base 4 upper surfaces, to guarantee the accuracy of check.Certainly, leveller is not limited to be arranged on base 4 upper surfaces, as long as can guarantee, to the leveling of sensor checking system, to be arranged on other position also passable, as, being arranged on the lower surface of base 4, also can be arranged between base 4 and roller.In addition, in order to improve the effect of leveller leveling, can also on base 4, level meter be set, to check the level that whether is adjusted to.Should be appreciated that, leveling is here the accuracy in order to check, and its leveling might not be defined as " level ", should regulate according to needing in the use procedure of sensor checking system.The first installation portion that is appreciated that above-mentioned stationary installation is arranged on the hydraulic arm of hydraulic means, and preferred, this first installation portion can be integral piece with hydraulic arm.In addition, hydraulic cylinder and hydraulic pump are preferably in base 4 inside, and reversal valve 6 and the hand lever in the time using hydraulic hand-pump, preferably in base 4 outsides, like this, hydraulic cylinder and hydraulic pump can obtain the protection of base 4, thereby increase the service life.Certainly, hydraulic cylinder is arranged on underbeam, and does not conflict in base inside.
Referring to Fig. 4, a kind of sensor inspection party of the sensor checking system based on above-mentioned, comprising:
Step S1: standard transducer 3 and sensor to be tested 2 are longitudinally coaxially in series arranged between described upper beam and underbeam by stationary installation.
Step S2: standard transducer 3 and the sensor to be tested of longitudinally coaxial series connection are applied to pulling force or pressure by hydraulic means.Longitudinally coaxial series connection, can make the two be subject to the power that hydraulic means applies identical.
Step S3: record respectively the first numerical value of described standard transducer 3 and the second value of described sensor to be tested by data acquisition unit, and described the first numerical value and second value are sent to respectively to data processor.
Step S4: described data processor is determined the difference of described second value and described the first numerical value, if difference falls into default range of allowable error, determines that sensor to be tested is qualified, otherwise, calibrate sensor to be tested according to difference.
In addition, between step S1 and step S2, there is a set-up procedure S
adjust, standard transducer 3 and sensor to be tested are positioned between hydraulic means and described upper beam, adjust the upper depth of beam of hydraulic means, fixing described standard transducer 3 and sensor to be tested.In step S2, adjust hydraulic pump, make hydraulic means apply pulling force or pressure to standard transducer 3 and sensor to be tested, further, reversal valve 6 is adjusted to primary importance, hydraulic means applies pulling force to standard transducer 3 and sensor to be tested; Or reversal valve 6 is adjusted to the second place, hydraulic means is exerted pressure to standard transducer 3 and sensor to be tested.Certainly,, in checkout procedure, programmable power supply provides constant voltage or Constant Electric Current to sensor to be tested.
In step s2, adjust hydraulic pump, make hydraulic means apply pulling force or pressure to standard transducer and sensor to be tested.Reversal valve is adjusted to primary importance, and hydraulic means applies pulling force to standard transducer and sensor to be tested; Or reversal valve is adjusted to the second place, described hydraulic means is exerted pressure to standard transducer and sensor to be tested.Like this, both can be for inspection pressure sensor, also can be for detection of pulling force sensor, certainly, in the time detecting pulling force sensor, on upper beam, can also be provided for the clip of fixation of sensor, and also can apply pulling force to standard transducer and sensor to be tested respectively in the time detecting, record respectively the first and second above-mentioned numerical value.
Based on the method for inspection of sensor checking system of the present utility model, also there is shirtsleeve operation step, these make sensor checking system of the present utility model can arrive the field test of customer equipment place, easy to use, have compared with traditional check system more can save time, the advantage such as traffic cost.
Although described the utility model and advantage thereof in detail, be to be understood that in the case of not exceeding the spirit and scope of the present utility model that limited by appended claim and can carry out various changes, alternative and conversion.And the application's scope is not limited only to the specific embodiment of the described process of instructions, equipment, means, method and step.One of ordinary skilled in the art will readily appreciate that from disclosure of the present utility model, can use and carries out with the essentially identical function of corresponding embodiment described herein or obtain process, equipment, means, method or step result essentially identical with it, that existing and will be developed future according to the utility model.Therefore, appended claim is intended to comprise such process, equipment, means, method or step in their scope.
Claims (6)
1. a sensor checking system, is characterized in that, comprising:
Hydraulic amplifier system, standard transducer, sensor to be tested, data acquisition unit and data processor;
Described hydraulic amplifier system comprises: at least one column; Underbeam, is fixedly connected on the first end of described column; Upper beam, is arranged at the second end of described column, and parallel with described underbeam; Stationary installation, for being longitudinally coaxially series at described standard transducer and described sensor to be tested between described upper beam and underbeam; And hydraulic means, is arranged on described underbeam, for described standard transducer and to be tested are applied to pulling force or pressure;
Described standard transducer is connected with described data processor through described data acquisition unit respectively with described sensor to be tested.
2. sensor checking system according to claim 1, is characterized in that,
The measuring accuracy grade of described standard transducer is higher than the measuring accuracy grade of described sensor to be tested.
3. sensor checking system according to claim 1, is characterized in that,
Described sensor checking system also comprises: at least one programmable power supply, is used to described sensor to be tested that constant voltage or Constant Electric Current are provided.
4. sensor checking system according to claim 1, is characterized in that,
Described data acquisition unit comprises:
The first digital multimeter, is connected with described standard transducer and described data processor respectively, for gathering the measurement data of described standard transducer and sending to described data processor;
The second digital multimeter, is connected with described sensor to be measured and described data processor respectively, for gathering the measurement data of described sensor to be measured and sending to described data processor.
5. sensor checking system according to claim 1, is characterized in that,
Described hydraulic means comprises: hydraulic cylinder, hydraulic arm, hydraulic pump and reversal valve; Wherein:
Described hydraulic cylinder is fixedly installed on described underbeam;
Described hydraulic arm moves upward in the side that is parallel to described column;
The size of the acting force that described hydraulic pump adjustment applies to liquid in described hydraulic cylinder;
Described reversal valve is connected with described hydraulic pump and described hydraulic cylinder respectively, for changing the direction of the acting force that described hydraulic pump applies to liquid in described hydraulic cylinder.
6. according to the sensor checking system described in claim 1-5 any one, it is characterized in that,
Described sensor checking system also comprises base, has holding area;
Described hydraulic amplifier system is arranged at described base top;
Described data processor is arranged in described holding area.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320665000.4U CN203616051U (en) | 2013-10-25 | 2013-10-25 | Sensor checking system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320665000.4U CN203616051U (en) | 2013-10-25 | 2013-10-25 | Sensor checking system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN203616051U true CN203616051U (en) | 2014-05-28 |
Family
ID=50768685
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201320665000.4U Expired - Fee Related CN203616051U (en) | 2013-10-25 | 2013-10-25 | Sensor checking system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN203616051U (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103575460A (en) * | 2013-10-25 | 2014-02-12 | 北京中科泛华测控技术有限公司 | Sensor checking system and method |
| CN106128971A (en) * | 2016-07-27 | 2016-11-16 | 常州天合光能有限公司 | Solar components encapsulation laminating machine vacuum system on-line calibration devices and methods therefor |
| CN108844677A (en) * | 2018-08-31 | 2018-11-20 | 无锡市瑞丰计量科技有限公司 | A kind of force snesor calibrating installation |
-
2013
- 2013-10-25 CN CN201320665000.4U patent/CN203616051U/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103575460A (en) * | 2013-10-25 | 2014-02-12 | 北京中科泛华测控技术有限公司 | Sensor checking system and method |
| CN103575460B (en) * | 2013-10-25 | 2016-03-30 | 北京中科泛华测控技术有限公司 | Sensor check system and method |
| CN106128971A (en) * | 2016-07-27 | 2016-11-16 | 常州天合光能有限公司 | Solar components encapsulation laminating machine vacuum system on-line calibration devices and methods therefor |
| CN108844677A (en) * | 2018-08-31 | 2018-11-20 | 无锡市瑞丰计量科技有限公司 | A kind of force snesor calibrating installation |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103575460B (en) | Sensor check system and method | |
| CN103575461A (en) | Sensor checking system and method | |
| CN203616051U (en) | Sensor checking system | |
| CN105300594A (en) | Calibration device and calibration method of tension sensor | |
| CN103018006A (en) | Device and method for bending moment calibration of measurement beam for ship model wave load test | |
| CN206787816U (en) | Guard against error railing horizontal thrust load testing machine | |
| CN203455227U (en) | Point load test instrument | |
| CN202974526U (en) | Static torque detection device | |
| CN202329505U (en) | Position error inspection jig | |
| CN204988132U (en) | Gyroscope rotor axle clearance measuring device | |
| CN208505194U (en) | A kind of measuring device of large-sized optical elements | |
| CN105547584A (en) | Portable tension value system field calibration device | |
| CN204043577U (en) | A kind of lever internal bore groove apparatus for detecting diameter | |
| CN204903046U (en) | Starter shift fork spring dynamometer | |
| CN204405174U (en) | A kind of proving installation of LOAD CELLS | |
| CN106769609B (en) | Fishing line softness testing device and method | |
| CN104422560A (en) | Sensor detection device | |
| CN206618636U (en) | Sponge stress test device | |
| CN203811325U (en) | Tension sensor testing device | |
| CN104056881A (en) | Metal plate bending device | |
| CN104614060B (en) | Online calibration device for electronic scale | |
| CN204269033U (en) | For single-chip measurer for thickness | |
| CN202453517U (en) | Gravity acceleration gauge | |
| CN203616049U (en) | Sensor detection apparatus | |
| CN206281482U (en) | A kind of device measured across waters deflection of bridge span |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20140528 Termination date: 20181025 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |