CN110220641B - Static torque calibration device and calibration method - Google Patents
Static torque calibration device and calibration method Download PDFInfo
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- CN110220641B CN110220641B CN201910623129.0A CN201910623129A CN110220641B CN 110220641 B CN110220641 B CN 110220641B CN 201910623129 A CN201910623129 A CN 201910623129A CN 110220641 B CN110220641 B CN 110220641B
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- 230000003068 static effect Effects 0.000 title claims abstract description 23
- 238000000034 method Methods 0.000 title claims abstract description 17
- 238000011068 loading method Methods 0.000 claims abstract description 21
- 238000005259 measurement Methods 0.000 claims abstract description 7
- 230000005540 biological transmission Effects 0.000 claims description 15
- 230000005484 gravity Effects 0.000 claims description 5
- 238000001514 detection method Methods 0.000 claims description 4
- 238000012886 linear function Methods 0.000 claims description 2
- 238000012545 processing Methods 0.000 claims description 2
- 238000012795 verification Methods 0.000 claims description 2
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- 238000012986 modification Methods 0.000 description 1
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Classifications
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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
- G01L25/003—Testing or calibrating of apparatus for measuring force, torque, work, mechanical power, or mechanical efficiency for measuring torque
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Abstract
The invention discloses a static torque calibration device and a calibration method, wherein the static torque calibration device works in cooperation with a loading device and comprises a connecting piece, an outer shell, a torque sensor to be calibrated, a wiring pipe and a high-precision torque sensor, wherein the torque sensor to be calibrated, the wiring pipe and the high-precision torque sensor are arranged in an inner cavity of the outer shell, the connecting piece is fixed at the upper end part of the torque sensor to be calibrated, the outer shell comprises a top cover, a supporting barrel and a mounting plate, the top cover is positioned and fixed at the top part of the supporting barrel through a spigot, the bottom part of the supporting barrel is fixed on the mounting plate, the torque sensor to be calibrated is fixed on the top cover, the high-precision torque sensor is connected with the torque sensor to be calibrated through a spline sleeve and a spline plate, and the high-precision torque sensor is positioned through the spigot and is arranged on the mounting plate through a screw and a high-precision torque sensor fixing plate, so that the problem of inaccurate measurement of the output torque of a numerical control machine tool spindle is solved.
Description
Technical Field
The invention belongs to the technical field of torque calibration devices, and particularly relates to a calibration device and a calibration method for calibrating a torque value measured by a torque sensor to be calibrated.
Background
The torque sensor is widely applied to the fields of machinery and automation as a torque measuring device, particularly to the field of torque fluctuation measurement of a main shaft of a numerical control machine tool, and is used as a key component for measuring the torque of the main shaft of the numerical control machine tool, and the measured torque value is also an important physical quantity representing the performance of the main shaft of the numerical control machine tool, so that the torque sensor is very important to calibrate. The existing calibration methods mainly comprise two types: one is to directly compare the output of the torque sensor with the result of the static loading, and the other is to calibrate the torque sensor to be calibrated with a higher accuracy torque sensor in the dynamic case. Both methods have the defects that the first static loading method has the high and low loading precision which directly influences the calibration precision, and various additional torques (including those generated by a connecting device, those generated by gravity and the like) can cause inaccurate calibration results; the second method is suitable for the form of horizontal connection, on one hand, the additional torque caused by gravity can lead to inaccurate calibration, and on the other hand, the transmission of motor output torque fluctuation can lead to different measuring results of torque sensors at different positions.
Disclosure of Invention
In order to overcome the technical problems in the prior art, the invention aims to provide a static torque calibration device and a static torque calibration method, which ensure the accuracy of a torque value measured by a torque sensor to be calibrated.
The invention provides a static torque calibration device which works in cooperation with a loading device, and comprises a connecting piece, an outer shell, a torque sensor to be calibrated, a wiring pipe and a high-precision torque sensor, wherein the torque sensor to be calibrated, the wiring pipe and the high-precision torque sensor are arranged in an inner cavity of the outer shell, the connecting piece is fixed at the upper end part of the torque sensor to be calibrated, the outer shell comprises a top cover, a supporting barrel and a mounting disc, the top cover is positioned through a spigot and is fixed at the top part of the supporting barrel through a screw, the supporting barrel is positioned through the spigot and is fixed on the mounting disc through the bottom part of the supporting barrel, the torque sensor to be calibrated is positioned through the spigot and is fixed on a top cover through the screw, the further torque sensor to be calibrated is fixed on the lower surface of the top cover, and the high-precision torque sensor is connected with the spline housing through a spline housing and a spline housing through the screw and a high-precision torque sensor fixing plate.
The spigot is commonly called as a yin-yang ridge and is a structure for centering and connecting
The upper end of the torque sensor to be calibrated is exposed out of the upper surface of a top cover arranged on the outer shell, and is connected with a connecting piece through a flat key, and the flat key is screwed down through a nut to prevent falling.
The wiring pipe is horizontally arranged and fixed on the barrel wall of the supporting barrel, one end of the wiring pipe extends into the supporting barrel, the other end of the wiring pipe extends out of the supporting barrel, and the part inside the supporting barrel is longer than the part outside the supporting barrel.
Further the wiring tube sets up and is 90 angles with the moment of torsion transmission stick, support barrel upper and lower part all is equipped with the wiring tube, and two wiring tube parallel arrangement of setting, the wiring tube that support barrel upper and lower part set up is used for waiting to calibrate moment of torsion sensor and high accuracy moment of torsion sensor to walk the line respectively.
The inner wall of the supporting barrel is provided with a grid plate, a fixing piece is arranged on the grid plate, a further fixing piece is positioned through a spigot and fixed on the grid plate through a screw, and a bearing is arranged on the fixing piece and is used for supporting the spline housing and adjusting centering.
The spline disc comprises a spline shaft arranged on the upper portion and a disc arranged at the bottom, the disc is fixedly connected with the high-precision torque sensor through a screw, the bottom of the spline housing is sleeved on the spline shaft, and the top of the spline housing is connected with the torque sensor to be calibrated.
The high-precision torque sensor fixing plate is L-shaped.
The loading device comprises a torque transmission rod, a fixed pulley and a weight disc, wherein the torque transmission rod is horizontally arranged and fixed at the top of the connecting piece, the fixed pulley is arranged at the tail end of the torque transmission rod, and the weight disc is connected to the fixed pulley.
The static torque calibration device and the static torque calibration method have the advantages that the torque loading device and the high-precision torque sensor are calibrated, the high-precision torque sensor arranged on the bottom end mounting plate is used for calibrating the torque sensor to be calibrated, the accuracy of a torque value measured by the torque sensor to be calibrated is ensured, and the problem of inaccurate measurement of the fluctuation of the output torque of the spindle of the numerical control machine tool is solved.
Drawings
FIG. 1 is a schematic overall construction of an embodiment of the present invention;
fig. 2 is a cross-sectional view A-A of fig. 1.
The drawing is marked:
1. A connecting piece; 2. a top cover; 3. a supporting barrel; 4. a torque sensor to be calibrated; 5. a wiring tube; 6. a fixing member; 7. a spline housing; 8. a flower keyboard; 9. a high-precision torque sensor; 10. a mounting plate; 11. a high-precision torque sensor fixing plate; 12. a weight tray; 13. a fixed pulley; 14. a torque transmission rod; 15. a flat key; 16. a bearing; 17. a grid plate; 18. a spline shaft; 19. a disk.
Detailed Description
The static torque calibration device and the static torque calibration method provided by the invention are described in detail below with reference to the accompanying drawings in combination with an embodiment.
Examples
Referring to fig. 1-2, a static torque calibration device of the present embodiment works in cooperation with a loading device, and includes a connecting piece 1, an outer housing, a torque sensor 4 to be calibrated, a wiring pipe 5, and a high-precision torque sensor 9, where the torque sensor 4 to be calibrated, the wiring pipe 5, and the high-precision torque sensor 9 are disposed in an inner cavity of the outer housing, the connecting piece 1 is fixed at an upper end of the torque sensor 4 to be calibrated, the outer housing includes a top cover 2, a supporting barrel 3, and a mounting disc 10, the top cover 2 is positioned by a spigot and is fixed at a top of the supporting barrel 3 by a screw, the supporting barrel 3 is positioned by the spigot, and the bottom is fixed on the mounting disc 10 by a screw, the torque sensor 4 to be calibrated is positioned by the spigot and is fixed on the top cover 2 by a screw, the further torque sensor 4 to be calibrated is fixed at a lower surface of the top cover 2, and the high-precision torque sensor 9 and the torque sensor 4 to be calibrated are connected by a spline sleeve 7 and a spline disc 8, and the high-precision torque sensor 9 is fixed on the mounting disc 11 by a screw and a high-precision sensor mounting disc 11.
The spigot is commonly called a yin-yang ridge and is a structure for centering and connecting.
The upper end of the torque sensor 4 to be calibrated is exposed out of the upper surface of the top cover 2 arranged on the outer shell, and is connected with the connecting piece 1 through the flat key 15, and the flat key 15 is screwed tightly and prevented from falling off through a nut.
The spool 5 level sets up to be fixed on supporting barrel 3 barrel wall, and one end extends to supporting barrel 3 inside, and the other end extends supporting barrel 3, and the inside part of supporting barrel 3 is longer than the part that extends outside the barrel, further spool 5 sets up and is 90 angles with torque transmission stick 14, supporting barrel upper and lower part all is equipped with spool 5, two spool parallel arrangement of setting, spool that the lower part was set up is used for waiting to calibrate torque sensor 4 and high accuracy torque sensor 9 respectively to walk the line.
The inner wall of the supporting barrel 3 is provided with an annular grid plate, a fixing piece 6 is arranged on the grid plate 17, the further fixing piece 6 is positioned through a spigot and fixed on the grid plate through a screw, a bearing 16 is arranged on the fixing piece 6, and the bearing 16 is used for supporting the spline housing 7 and adjusting centering.
The spline disc 8 comprises a spline shaft 18 arranged at the upper part and a disc 19 arranged at the bottom, the disc 19 is fixedly connected with the high-precision torque sensor 9 through a screw, the bottom of the spline housing 8 is sleeved on the spline shaft 18, and the top of the spline housing 7 is connected with the torque sensor to be calibrated 4
The high-precision torque sensor fixing plate 11 is L-shaped.
The top of the connecting piece 1 is connected with a loading device, the loading device comprises a torque transmission rod 14, a fixed pulley 13 and a weight tray 12, the torque transmission rod 14 is horizontally arranged and fixed at the top of the connecting piece 1, the fixed pulley 13 is arranged at the tail end of the torque transmission rod 14, and the weight tray 12 is connected to the fixed pulley 13.
The utility model provides a static torque calibrating device has guaranteed the axiality of shafting through tang location, treats the calibration torque sensor through installing the high accuracy torque sensor on the bottom mounting disc and calibrates, and vertical calibrating device has prevented that gravity from bringing additional torque influence, has guaranteed pure torque loading through special loading device.
The use calibration method of the static torque calibration device comprises the following steps:
First verification torque calibration device
The torque calibration device is calibrated through the calibrated high-precision torque sensor, the torque calibration device is installed at the position where the torque sensor to be calibrated is installed, the torque calibration device is gradually applied with torque from small to large by adopting the loading device until the torque is set value, the high-precision torque sensor obtains a torque value measured by the torque calibration device during detection, the corresponding relation between the torque value measured by the high-precision torque sensor calibrated during detection and the torque value measured by the high-precision torque sensor of the torque calibration device is recorded, a linear function relation formula is calculated by using a least square method, and the accurate value of the torque measured by the torque sensor to be calibrated is calculated according to the torque value measured by the high-precision torque sensor of the torque calibration device and the relation function during actual calibration.
(II) calibrating the output torque of the torque sensor to be calibrated by adopting the torque calibration device
1. Positioning a torque sensor to be calibrated through a spigot, fixing the torque sensor to be calibrated on a top cover through a screw, connecting the upper end of the torque sensor to be calibrated with a connecting piece through a flat key, and screwing the torque sensor to be calibrated by using an M36 nut; the lower end of the torque sensor to be calibrated is connected with the connecting spline housing through a flat key and is screwed by using an M48 nut; the torque sensor to be calibrated and the high-precision torque sensor are connected through a spline housing and a spline disc, and the spline housing is supported and adjusted to be centered through a high-precision bearing.
2. The special loading device is connected with the connecting piece, a small amount of torque is applied through the self gravity action of the weight tray through the pin positioning of the design, the weight tray is hung in which direction by loading in which direction, the fact that one side of an internal spline of the internal connection spline housing of the torque calibration device is completely attached to one side of an external spline of the torque transmission spline board at the moment is guaranteed, and all intermediate connection structures are guaranteed to complete deformation.
3. After the shafting state is confirmed, the special loading device starts to slowly apply linearly increased torque values in the forward direction and the reverse direction until the full range is reached, and the shafting of the torque calibrating device has a rotating trend, so that all parts are deformed to transmit torque, but real rotation does not occur. In the calibration process, the readings of the high-precision torque sensor and the readings of the torque sensor to be calibrated in the torque calibration device are synchronously recorded.
And repeating the step 3 for three times, and calculating the torque compensation value of each torque measuring point of the torque sensor to be calibrated after system data processing according to the measured value of each torque measuring point in the three times of measurement. The torque compensation values of the measurement points are listed as follows:
| torque measurement | ||||
| Torque compensation value |
The foregoing is only a preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art, who is within the scope of the present invention, should make equivalent substitutions or modifications according to the technical scheme of the present invention and the inventive concept thereof, and should be covered by the scope of the present invention.
Claims (6)
1. The utility model provides a static torque calibrating device, cooperation loading device work which characterized in that: the high-precision torque sensor is positioned through the spigot and is fixed on the mounting plate through the screw, the torque sensor to be calibrated is positioned through the spigot and is fixed on the top cover through the screw, the high-precision torque sensor is connected with the torque sensor to be calibrated through the spline sleeve and the spline plate, the spline plate comprises a spline shaft arranged at the upper part and a disc arranged at the bottom, the disc is fixedly connected with the torque sensor to be calibrated, the bottom of the spline sleeve is sleeved on the spline shaft, the top of the spline sleeve is connected with the torque sensor to be calibrated, and the torque sensor to be calibrated is positioned through the spigot and is fixed on the mounting plate through the screw;
The method for calibrating the static torque calibration device comprises the following specific steps:
first verification torque calibration device
The method comprises the steps of calibrating a torque calibration device through a calibrated high-precision torque sensor, installing the torque calibration device at a position where the torque sensor to be calibrated is installed, gradually applying torque to the torque calibration device from small to large by adopting a loading device until the torque calibration device reaches a set value, acquiring a torque value measured by the torque calibration device during detection by the high-precision torque sensor, recording a corresponding relation between the torque value measured by the high-precision torque sensor calibrated during detection and the torque value measured by the high-precision torque sensor of the torque calibration device, calculating a linear function relation formula by using a least square method, and calculating an accurate value of the torque measured by the torque sensor to be calibrated according to the torque value measured by the high-precision torque sensor of the torque calibration device and a relation function during actual calibration;
(II) calibrating the output torque of the torque sensor to be calibrated by adopting the torque calibration device
1. Positioning a torque sensor to be calibrated through a spigot, fixing the torque sensor to be calibrated on a top cover through a screw, connecting the upper end of the torque sensor to be calibrated with a connecting piece through a flat key, and screwing the torque sensor to be calibrated by using an M36 nut; the lower end of the torque sensor to be calibrated is connected with the connecting spline housing through a flat key and is screwed by using an M48 nut; the torque sensor to be calibrated and the high-precision torque sensor are connected through a spline housing and a spline disc, and the spline housing is supported and adjusted to be centered through a high-precision bearing;
2. the special loading device is connected with the connecting piece, a small amount of torque is applied through the self gravity action of the weight tray through the designed pin positioning, the weight tray is hung in which direction when being loaded in which direction, the fact that one side of an internal spline of the internal connection spline housing of the torque calibration device is completely attached to one side of an external spline of the torque transmission spline board at the moment is ensured, and all intermediate connection structures are ensured to complete deformation;
3. After the shafting state is confirmed, the special loading device starts to slowly apply linearly increased torque values in the forward direction and the reverse direction until the full range is reached, and the shafting of the torque calibration device has a rotating trend, so that all parts are deformed to transmit torque, but real rotation does not occur; in the calibration process, synchronously recording the indication of a high-precision torque sensor in the torque calibration device and the indication of the torque sensor to be calibrated;
And repeating the step 3 for three times, and calculating the torque compensation value of each torque measuring point of the torque sensor to be calibrated after system data processing according to the measured value of each torque measuring point in the three times of measurement.
2. The static torque calibration device according to claim 1, characterized in that: the upper end of the torque sensor to be calibrated is exposed out of the upper surface of a top cover arranged on the outer shell, and is connected with a connecting piece through a flat key, and the flat key is screwed down through a nut.
3. The static torque calibration device according to claim 1, characterized in that: the wiring pipe is horizontally arranged and fixed on the barrel wall of the supporting barrel, one end of the wiring pipe extends into the supporting barrel, and the other end of the wiring pipe extends out of the supporting barrel.
4. The static torque calibration device according to claim 1, characterized in that: the inner wall of the supporting barrel is provided with a grid plate, a fixing piece is arranged on the grid plate, and a bearing is arranged on the fixing piece.
5. The static torque calibration device according to claim 1, characterized in that: the high-precision torque sensor fixing plate is L-shaped.
6. The static torque calibration device according to claim 1, characterized in that: the loading device comprises a torque transmission rod, a fixed pulley and a weight disc, wherein the torque transmission rod is horizontally arranged and fixed at the top of the connecting piece, the fixed pulley is arranged at the tail end of the torque transmission rod, and the weight disc is connected to the fixed pulley.
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| CN201910623129.0A CN110220641B (en) | 2019-07-11 | 2019-07-11 | Static torque calibration device and calibration method |
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| CN110220641B true CN110220641B (en) | 2024-07-19 |
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| CN110823438B (en) * | 2019-11-22 | 2021-04-06 | 湖南省计量检测研究院 | Method for detecting torque value of torque control device |
| CN110849536B (en) * | 2019-12-06 | 2024-04-12 | 天顶星（天津）电子科技有限责任公司 | Torque sensor calibrating device |
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| DE102006055614A1 (en) * | 2006-11-24 | 2008-05-29 | Horiba Automotive Test Systems Gmbh | Apparatus and method for calibrating torque measuring devices |
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| CN105509960B (en) * | 2015-12-11 | 2018-01-19 | 天津七一二通信广播股份有限公司 | A kind of mechanical device and method applied to torque sensor calibration |
| CN106840517B (en) * | 2017-03-02 | 2022-07-26 | 天津大学 | Output torque calibrator for speed reducer detector |
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|---|---|---|---|---|
| CN106989868A (en) * | 2017-03-02 | 2017-07-28 | 天津大学 | A kind of calibration method of decelerator detector output torque |
| CN106996849A (en) * | 2017-06-08 | 2017-08-01 | 中国船舶重工集团公司第七0四研究所 | Standard torque spanner calibrating installation based on air bearings support |
| CN108760150A (en) * | 2018-07-16 | 2018-11-06 | 中国航空工业集团公司北京长城计量测试技术研究所 | A kind of large size force value asymmetrical load power and torque decouple calibrating installation |
| CN210802769U (en) * | 2019-07-11 | 2020-06-19 | 山东省青岛第四十五中学（青岛工贸职业学校） | Static torque calibrating device |
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