CN114858346A - Calibration device and calibration method for hanging frame type micro dynamometer - Google Patents
Calibration device and calibration method for hanging frame type micro dynamometer Download PDFInfo
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- CN114858346A CN114858346A CN202210616861.7A CN202210616861A CN114858346A CN 114858346 A CN114858346 A CN 114858346A CN 202210616861 A CN202210616861 A CN 202210616861A CN 114858346 A CN114858346 A CN 114858346A
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- 238000000034 method Methods 0.000 title claims description 15
- 230000005484 gravity Effects 0.000 claims abstract description 5
- 230000005540 biological transmission Effects 0.000 abstract description 3
- 238000009434 installation Methods 0.000 description 4
- 238000010586 diagram Methods 0.000 description 2
- 230000007547 defect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
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- 238000003825 pressing Methods 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L25/00—Testing or calibrating of apparatus for measuring force, torque, work, mechanical power, or mechanical efficiency
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Abstract
The invention provides a hanger type micro dynamometer calibration device, which comprises a force transducer mounting base, a movable calibration frame and a vertical frame; the lower part of the force transducer mounting base is mounted on the vertical frame, and the upper part of the force transducer mounting base is provided with a force transducer mounting platform; the movable calibration frame comprises a top hanging frame, a middle connecting rod and a bottom counterweight frame, the top hanging frame is movably hung on the vertical frame, and the position on the force measuring sensor mounting platform for mounting the sensor is vertically superposed with the gravity center of the top hanging frame; the bearing and hoisting position of the top hanging bracket is provided with a vertical movable hole, so that after the top hanging bracket is jacked up, the movable calibration frame is not in contact with the vertical frame and the force cell sensor mounting foundation. The device is through separating the activity calibration frame completely, only with the dynamometry sensor contact that receives, guarantees that the whole weight of activity calibration frame can effectively transmit to the dynamometry sensor, and then solves the problem that has other bearing structure and lead to the transmission process of power to be influenced.
Description
Technical Field
The invention relates to a calibration device of a micro dynamometer, in particular to a hanger type calibration device of a micro dynamometer and a calibration method.
Background
The calibration work of the dynamometer is mainly to calibrate the force transducer, and the precision of the transducer directly determines the precision of the dynamometer.
Most of the conventional dynamometer calibration devices are too complex and high in cost, and are not easy to popularize and apply.
The reason is that the accuracy of the magnitude of the force applied by the device itself is difficult to control.
It is common practice to use weights for calibration, but it is not known whether the force-conducting structure will be a loss.
If the application number is: 201220559410.6, title of the invention: the utility model discloses a quiet heavy miniature force cell sensor calibration device of air supporting is with air supporting axle cooperation weight, marks force sensor.
However, the weight passes through the air floating shaft in the process of transferring the weight to the sensor, and although the principle of the air floating shaft is that air is used as a lubricant to achieve the purpose of reducing friction force, whether the air floating shaft can really ensure complete suspension in the application process is unknown actually.
In order to solve the above problems, people are always seeking an ideal technical solution.
Disclosure of Invention
The invention aims to overcome the defects of the prior art, and provides a hanger type micro dynamometer calibration device and a calibration method, which solve the problem of insufficient weight transfer caused by contact between a calibration reference object and an external support and improve calibration accuracy.
In order to achieve the purpose, the invention adopts the technical scheme that: a calibration device of a hanging bracket type micro dynamometer comprises a force cell sensor mounting base with adjustable vertical height, a movable calibration frame for balancing weight and a vertical frame;
the lower fixed part of the force sensor mounting base is mounted on the vertical frame, and the top end of the upper movable part of the force sensor mounting base is provided with a force sensor mounting platform;
the movable calibration frame comprises a top hanging frame, a middle connecting rod and a bottom counterweight frame which are connected together, the top hanging frame is movably hung on the vertical frame, and the center of the position on the force measuring sensor mounting platform for mounting the sensor is vertically coincided with the gravity center of the top hanging frame;
and a vertical movable hole is formed in the hanging part of the top hanging frame, so that the movable calibration frame is not in contact with the vertical frame and the force measuring sensor mounting foundation after the top hanging frame is jacked up under the jacking action of the force measuring sensor mounting foundation.
Basically, the bottom counterweight frame is positioned below the force measuring sensor mounting base, and an offset sensor is arranged corresponding to the top end hanging bracket or the middle connecting rod or the bottom counterweight frame.
Basically, a level gauge is arranged on the movable calibration frame.
Basically, the grudging post includes base, stand and top hoisting machine structure, the lower extreme of base is provided with levelling device.
Basically, force cell sensor installation basis includes layer board, vertical slip table, sensor seat and extension fixed column, the layer board is fixed in on the stand of grudging post, vertical slip table is fixed in on the layer board, the top of vertical slip table is fixed in to the sensor seat, the lower part of extension fixed column penetrates in the vertical blind hole in top of sensor fixing base, the top center department of extension fixed column sets up sensor installation half chamber, the up end face of extension fixed column forms force cell sensor mounting platform.
Basically, the top gallows includes the bar connecting plate of horizontal arrangement and the hangers that have vertical slot hole, the hangers constitutes the department that holds of top gallows, the hoisting machine of grudging post constructs including passing the peg that the vertical slot hole of hangers set up.
Basically, the supporting plate is provided with a through hole corresponding to the middle connecting rod, and the offset sensor is installed on the inner side of the through hole.
Basically, the bottom counterweight frame comprises a chassis and a weight placing position arranged at the center of the chassis.
The calibration method of the micro dynamometer comprises the hanger type micro dynamometer calibration device and comprises the following steps:
step 1) leveling the vertical frame to ensure that the movable calibration frame is not deflected in the vertical direction under the natural drooping state;
step 2) controlling the force sensor mounting base to move downwards to be separated from the top hanging bracket, mounting the force sensor on a force sensor mounting platform, and ensuring that the force bearing surface of the force sensor faces upwards and is higher than the force sensor mounting platform;
and 3) controlling the lifting of the force sensor mounting base, enabling the force sensor to be in contact with the top hanging bracket, jacking the top hanging bracket to enable the top hanging bracket to be kept in a state after being completely separated from the vertical frame, observing that the movable calibration frame is not in contact with the vertical frame and the force sensor mounting base and is in a balanced state, reading the reading of the force sensor, judging whether the reading is consistent with the weight data of the movable calibration frame, and further calibrating the force sensor.
Basically, in the step 3), whether the movable calibration frame is in a horizontal state or not is observed through the level meter, and if the movable calibration frame is inclined, the movable calibration frame can be manually adjusted until the movable calibration frame is in the horizontal state.
Compared with the prior art, the invention has outstanding substantive characteristics and remarkable progress, and particularly, the invention adopts a set of movable calibration frame as a calibration reference object, the self weight of the movable calibration frame is standard weight, then a vertical frame, a hoisting structure and a force sensor mounting base are designed, the force sensor to be tested is contacted with a top hanging bracket of the calibration movable frame and jacked up by controlling the lifting of the force sensor mounting base, due to the design of a vertical movable hole at a bearing and hanging part, the movable calibration frame is not contacted with the vertical frame and the force sensor mounting base and is only contacted with the force sensor, so that the whole weight of the movable calibration frame is transmitted to the force sensor, the problem of the accuracy of a pressure applying mechanism in the traditional method for externally applying pressure to the force sensor is solved, and simultaneously, the method for transmitting the weight between the calibration reference object and the force sensor through an intermediate piece is abandoned, the problem of insufficient force transmission caused by the problem of friction and other resistance possibly existing in the intermediate piece is solved.
Because the middle transmission part and the force application mechanism are cancelled, the calibration is carried out by adopting the static calibration reference object with standard weight, the calibration accuracy is greatly improved, and a series of problems that the force bearing surface of the miniature force transducer is small and the calibration is difficult to directly carry out are solved.
Furthermore, in order to prevent the movable calibration frame from deflecting, and contacting with the vertical frame or a force sensor mounting base in the calibration process, or the problem that the force sensor cannot fully sense gravity due to gravity center offset, detection devices such as an offset sensor and a level meter are mounted to ensure the stability of the movable calibration frame in the calibration process, and meanwhile, in order to ensure the stability of the whole system, a leveling mechanism is also arranged at the bottom end of the vertical frame.
Furthermore, in order to conveniently install the force sensor, the force sensor installation foundation is designed to be a structure comprising a vertical sliding table, a sensor seat and an elongated fixed column, the elongated fixed column is stably matched with the sensor seat, and the problem that the miniature force sensor is too small in size and not easy to directly install on the sliding table or the sensor seat is mainly solved.
Drawings
Fig. 1 is a schematic structural diagram of a calibration device of a hanging bracket type micro dynamometer in the invention.
Fig. 2 is a second schematic structural diagram of the calibration device of the hanging bracket type micro dynamometer in the invention.
In the figure: 1. erecting a frame; 1-1, upright column; 1-2. hanging rod 2. force transducer mounting base; 2-1, a supporting plate; 2-2, a vertical sliding table; 2-3, sensor seat; 2-4, lengthening the fixing column; 2-5, punching; 3, a movable calibration frame; 3-1. a top hanger; 3-2, a middle connecting rod; 3-3, bottom counterweight frame; 3-4, vertical long holes; 3-5, connecting bar; 4. a weight; 5. a force sensor; 6. a leveling mechanism; 7. and a deviation rectifying sensor.
Detailed Description
The technical solution of the present invention is further described in detail by the following embodiments.
As shown in fig. 1 and 2, a hanger type micro dynamometer calibration device comprises a load cell installation base 2 with adjustable vertical height, a movable calibration frame 3 for counterweight and a vertical frame 1.
The lower fixed part of the force measuring sensor mounting base 2 is mounted on the vertical frame 1, and the top end of the upper movable part of the force measuring sensor mounting base 2 is provided with a force measuring sensor mounting platform.
In the embodiment, the force sensor mounting base 2 comprises a supporting plate 2-1, a vertical sliding table 2-2, a sensor seat 2-3 and a lengthened fixing column 2-4, the supporting plate 2-1 is fixed on a stand column 1-1 of the vertical frame 1, the vertical sliding table 2-2 is fixed on the supporting plate 2-1, the sensor seat 2-3 is fixed at the top end of the vertical sliding table 2-2, the lower portion of the lengthened fixing column 2-4 penetrates into a vertical blind hole in the top of the sensor fixing seat 2-2, a sensor mounting semi-cavity is arranged in the center of the top end of the lengthened fixing column 2-4 and used for mounting a force sensor 5, and the upper end face of the lengthened fixing column 2-4 forms a force sensor mounting platform.
The movable calibration frame 3 comprises a top hanging frame 3-1, a middle connecting rod 3-2 and a bottom counterweight frame 3-3 which are connected together, the top hanging frame is movably hung on the vertical frame 1, the top hanging frame 3-1 comprises horizontally arranged strip-shaped connecting plates 3-5 and hanging lugs with vertical long holes 3-4, the hanging lugs form a bearing and hanging position of the top hanging frame, a hanging mechanism of the vertical frame 1 comprises hanging rods 1-2 which penetrate through the vertical long holes of the hanging lugs, so that after the top hanging frame 3-1 is jacked up under the jacking action of a force measuring sensor 5 mounting base, the movable calibration frame 3 is not in contact with the vertical frame 1 and the force measuring sensor mounting base 2.
The bottom counterweight frame 3-3 is arranged below the force measuring sensor mounting base 2, and an offset sensor is arranged corresponding to the top end hanging bracket or the middle connecting rod or the bottom counterweight frame and used for preventing the movable calibration frame 3 from offsetting.
The supporting plate 2-1 is provided with a through hole 2-5 corresponding to the middle connecting rod 3-2, and in the embodiment, the offset sensor 7 is installed at the inner side of the through hole 2-5.
In various embodiments, the bottom weight rest comprises a chassis and a weight placement position arranged in the center of the chassis for placing the weight 4.
The calibration method comprises the following steps:
step 1) leveling the vertical frame to ensure that the movable calibration frame is not deflected in the vertical direction under the natural drooping state;
step 2) controlling the force sensor mounting base to move downwards to be separated from the top hanging bracket, mounting the force sensor on a force sensor mounting platform, and ensuring that the force bearing surface of the force sensor faces upwards and is higher than the force sensor mounting platform;
and 3) controlling the lifting of the force sensor mounting base, enabling the force sensor to be in contact with the top hanging bracket, jacking the top hanging bracket to enable the top hanging bracket to be kept in a state after being completely separated from the vertical frame, observing that the movable calibration frame is not in contact with the vertical frame and the force sensor mounting base and is in a balanced state, reading the reading of the force sensor, judging whether the reading is consistent with the weight data of the movable calibration frame, and further calibrating the force sensor.
And 3) observing whether the movable calibration frame is in a horizontal state or not through the level meter, and if the movable calibration frame is inclined, manually adjusting the movable calibration frame until the movable calibration frame is in the horizontal state.
It should be noted that the movable calibration frame 3 can be used as a calibration reference object itself, and can be used as a standard object to calibrate the load cell by limiting and calibrating the weight of the movable calibration frame itself.
In other schemes, the movable calibration frame 3 is not used as a standard object, weights are used for calibration, when the movable calibration frame is used, peeling operation is firstly carried out on the empty movable calibration reference object 3, then the weights are put on, and the force measuring sensor is calibrated.
The weight can be replaced at will and adjusted into weight combinations with different weights, and the calibration process is more reasonable and flexible.
Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present invention and not to limit the same; although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art will understand that: modifications to the specific embodiments of the invention or equivalent substitutions for parts of the technical features may be made; without departing from the spirit of the present invention, it is intended to cover all aspects of the invention as defined by the appended claims.
Claims (10)
1. The utility model provides a miniature dynamometer calibration device of hanger bracket formula which characterized in that: the device comprises a force measuring sensor mounting base with adjustable vertical height, a movable calibration frame for balancing weight and a vertical frame;
the lower fixed part of the force sensor mounting base is mounted on the vertical frame, and the top end of the upper movable part of the force sensor mounting base is provided with a force sensor mounting platform;
the movable calibration frame comprises a top hanging frame, a middle connecting rod and a bottom counterweight frame which are connected together, the top hanging frame is movably hung on the vertical frame, and the center of the position on the force measuring sensor mounting platform for mounting the sensor is vertically coincided with the gravity center of the top hanging frame;
and a vertical movable hole is formed in the hanging part of the top hanging frame, so that the movable calibration frame is not in contact with the vertical frame and the force measuring sensor mounting foundation after the top hanging frame is jacked up under the jacking action of the force measuring sensor mounting foundation.
2. A hanger micro dynamometer calibration as claimed in claim 1 and including: the bottom counterweight frame is positioned below the force measuring sensor mounting base, and an offset sensor is arranged corresponding to the top end hanging bracket or the middle connecting rod or the bottom counterweight frame.
3. A hanger miniature dynamometer calibration as claimed in claim 1 or 2 and including: and a level gauge is arranged on the movable calibration frame.
4. A hanger miniature dynamometer calibration as claimed in claim 2 and including: the vertical frame comprises a base, a vertical column and a top hoisting mechanism, and a leveling device is arranged at the lower end of the base.
5. A hanger miniature dynamometer calibration as claimed in claim 4 and including: the force cell sensor mounting base comprises a supporting plate, a vertical sliding table, a sensor seat and an elongated fixing column, the supporting plate is fixed on a stand column of the vertical frame, the vertical sliding table is fixed on the supporting plate, the sensor seat is fixed on the top end of the vertical sliding table, the lower portion of the elongated fixing column penetrates into a vertical blind hole in the top of the sensor fixing seat, a sensor mounting semi-cavity is arranged at the center of the top end of the elongated fixing column, and the upper end face of the elongated fixing column forms the force cell sensor mounting platform.
6. A hanger miniature dynamometer calibration as claimed in claim 5 and including: the top hanging bracket comprises a horizontally arranged strip-shaped connecting plate and a hanging lug with a vertical long hole, the hanging lug forms a bearing and hanging position of the top hanging bracket, and the hanging mechanism of the vertical frame comprises a hanging rod which penetrates through the vertical long hole of the hanging lug.
7. A hanger miniature dynamometer calibration as claimed in claim 5 or 6 and including: the supporting plate is provided with a through hole corresponding to the middle connecting rod, and the offset sensor is installed on the inner side of the through hole.
8. A hanger miniature dynamometer calibration as claimed in claim 7 and including: the bottom counterweight frame comprises a chassis and a weight placing position arranged at the center of the chassis.
9. A calibration method of a micro dynamometer is characterized in that: comprising a suspended micro dynamometer calibration device according to anyone of claims 1-8, calibrated by:
step 1) leveling the vertical frame to ensure that the movable calibration frame is not deflected in the vertical direction under the natural drooping state;
step 2) controlling the force sensor mounting base to move downwards to be separated from the top hanging bracket, mounting the force sensor on a force sensor mounting platform, and ensuring that the force bearing surface of the force sensor faces upwards and is higher than the force sensor mounting platform;
and 3) controlling the lifting of the force sensor mounting base, enabling the force sensor to be in contact with the top hanging bracket, jacking the top hanging bracket to enable the top hanging bracket to be kept in a state after being completely separated from the vertical frame, observing that the movable calibration frame is not in contact with the vertical frame and the force sensor mounting base and is in a balanced state, reading the reading of the force sensor, judging whether the reading is consistent with the weight data of the movable calibration frame, and further calibrating the force sensor.
10. A method of calibrating a micro dynamometer according to claim 9, further comprising: and 3) observing whether the movable calibration frame is in a horizontal state or not through the level meter, and if the movable calibration frame is inclined, manually adjusting the movable calibration frame until the movable calibration frame is in the horizontal state.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210616861.7A CN114858346A (en) | 2022-06-01 | 2022-06-01 | Calibration device and calibration method for hanging frame type micro dynamometer |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202210616861.7A CN114858346A (en) | 2022-06-01 | 2022-06-01 | Calibration device and calibration method for hanging frame type micro dynamometer |
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| CN114858346A true CN114858346A (en) | 2022-08-05 |
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Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6009740A (en) * | 1997-02-21 | 2000-01-04 | Horiba Instruments, Inc. | System and method for deadweight calibrating a dynamometer |
| KR20100117213A (en) * | 2009-04-24 | 2010-11-03 | 주식회사 한발 | Rigid hanger load measure test & load adjustable method |
| CN101929905A (en) * | 2010-03-23 | 2010-12-29 | 昆山市创新科技检测仪器有限公司 | Reverse frame hanging device |
| CN201788055U (en) * | 2010-03-23 | 2011-04-06 | 昆山市创新科技检测仪器有限公司 | Force sensor calibration device and weight deflection preventing device thereof |
| CN106092400A (en) * | 2016-05-30 | 2016-11-09 | 寇明虎 | A kind of small force value force measuring machine |
| CN108120549A (en) * | 2016-11-30 | 2018-06-05 | 北京航天计量测试技术研究所 | Volume range force sensor calibrating installation |
| CN110793716A (en) * | 2019-11-27 | 2020-02-14 | 湖南景程电子科技有限公司 | Mounting device for pressure sensor calibration |
| CN111551311A (en) * | 2020-06-17 | 2020-08-18 | 河北省科学院应用数学研究所 | Pressure sensor calibration device and calibration method |
| CN114279632A (en) * | 2021-12-31 | 2022-04-05 | 西安交通大学 | Three-dimensional force loading calibration device and method for three-dimensional force sensor |
-
2022
- 2022-06-01 CN CN202210616861.7A patent/CN114858346A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6009740A (en) * | 1997-02-21 | 2000-01-04 | Horiba Instruments, Inc. | System and method for deadweight calibrating a dynamometer |
| KR20100117213A (en) * | 2009-04-24 | 2010-11-03 | 주식회사 한발 | Rigid hanger load measure test & load adjustable method |
| CN101929905A (en) * | 2010-03-23 | 2010-12-29 | 昆山市创新科技检测仪器有限公司 | Reverse frame hanging device |
| CN201788055U (en) * | 2010-03-23 | 2011-04-06 | 昆山市创新科技检测仪器有限公司 | Force sensor calibration device and weight deflection preventing device thereof |
| CN106092400A (en) * | 2016-05-30 | 2016-11-09 | 寇明虎 | A kind of small force value force measuring machine |
| CN108120549A (en) * | 2016-11-30 | 2018-06-05 | 北京航天计量测试技术研究所 | Volume range force sensor calibrating installation |
| CN110793716A (en) * | 2019-11-27 | 2020-02-14 | 湖南景程电子科技有限公司 | Mounting device for pressure sensor calibration |
| CN111551311A (en) * | 2020-06-17 | 2020-08-18 | 河北省科学院应用数学研究所 | Pressure sensor calibration device and calibration method |
| CN114279632A (en) * | 2021-12-31 | 2022-04-05 | 西安交通大学 | Three-dimensional force loading calibration device and method for three-dimensional force sensor |
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