A calibration device for a thrust balance

Abstract

A calibration device for a thrust balance, comprising a top support cross-frame and a left support frame and a right support frame respectively connected to both ends thereof. A flange connecting member, a thrust balance, an intermediate shaft and a thruster are sequentially connected downward below the top support cross-frame. A pulley frame is connected to the top support cross-frame on one side of the thruster. A pulley member is movably connected to the pulley frame. One end of a steel cable is fixedly connected to the center of the side surface on one side of the thruster. The other end of the steel cable extends downward after changing direction through the circumferential surface of the pulley member and is fixedly connected to a weight frame. Weights are installed in the weight frame. The steel cable between the thruster and the pulley member is parallel to the top support cross-frame. The steel cable between the pulley member and the weight frame is perpendicular to the top support cross-frame. During application, the thrust balance and the thruster can be replaced, and under the action of a single-side force, the force received by the thrust balance is constant, improving the accuracy and stability of the calibration device. Therefore, this design not only has a wide application range, but also has high calibration accuracy and stability.

Description

Technical Field

[0001] The present invention relates to a thruster calibration device, belonging to the field of ship power, and particularly to a calibration device for a thrust balance. Background Art

[0002] In the product test of a rim thruster, a thrust balance device is usually used, which is mainly used to measure the thrust generated by the rim thruster device under the rated power. Affected by the structure of the rim thruster product, when measuring the thrust, the thrust balance device is connected in the flange direction of the rim thruster, and forms a 90° angle with the thrust direction generated by the rim thruster, forming a cantilever structure. When measuring the thrust, the thrust balance cannot directly measure the thrust of the rim thruster. Instead, it calculates the thrust by the bending moment generated by the thrust of the thruster on the thrust balance and the corresponding relationship between the bending moment displacement and the strain. Since the sizes, structures, and installation forms of rim thrusters are different, the installation position distance of the thrust balance and the thrust center of the thruster are also different. Therefore, in order to accurately measure the thrust generated by the rim thruster under the rated power, the thrust balance needs to be calibrated before each product test to meet the requirements of rim thruster thrust measurement. In the prior art, a patent document with the application number: CN202010750750.6, the name: Helicopter Wind Tunnel Test Bench Balance Rotation Calibration Loading Device, and the application date: July 30, 2020 discloses that a device using multi-lateral tension can perform similar calibration work, but it still has the following defects:

[0003] This calibration device can only be used for a single type. It is manufactured separately according to the models of the thruster and the thrust balance, and cannot be matched and applied to different thrusters and thrust balances, so the applicable range is relatively narrow. Moreover, the multi-lateral tension causes uneven force on the thrust balance, resulting in low calibration accuracy and stability.

[0004] Disclosing the information of this background art section is only intended to increase the understanding of the overall background of the present application, and should not be regarded as an admission or any form of suggestion that this information constitutes the prior art already known to those of ordinary skill in the art. Summary of the Invention

[0005] The object of the present invention is to overcome the defects and problems in the prior art that the applicable range of the calibration device is relatively narrow, and the calibration accuracy and stability are not high, and to provide a calibration device for a thrust balance with a relatively wide applicable range and relatively high calibration accuracy and stability.

[0006] To achieve the above object, the technical solution of the present invention is: a calibration device for a thrust balance, the thrust balance calibration device comprising: a left support frame, a right support frame and a top support cross frame; one end of the top support cross frame is fixedly connected to the top end of the left support frame, and the other end of the top support cross frame is fixedly connected to the top end of the right support frame; the middle top surface of the top support cross frame is connected to the top end of the flange connecting member by a first bolt, the bottom end of the flange connecting member is connected to the top end of the thrust balance by a second bolt, the bottom end of the thrust balance is connected to the top end of the intermediate shaft by a third bolt, and the bottom end of the intermediate shaft is connected to the top end of the thruster by a fourth bolt; the bottom surface of the top support cross frame is fixedly connected with a pulley frame by a fifth bolt, the pulley frame is located on one side of the thruster, and the bottom end of the pulley frame is movably connected with a pulley member; one end of a steel cable is fixedly connected to the center of the side surface of one side of the thruster, and the other end of the steel cable extends downward after changing direction through the circumferential surface of the pulley member, and the other end of the steel cable is fixedly connected to a weight rack, and weights are installed in the weight rack;

[0007] The steel cable between the thruster and the pulley member is parallel to the top support cross frame, and the steel cable between the pulley member and the weight rack is perpendicular to the top support cross frame.

[0008] The pulley frame includes a pulley cross frame, a pulley vertical frame and a pulley inclined frame; the pulley cross frame is fixedly connected to the bottom surface of the top support cross frame by a fifth bolt; the bottom surface of one end of the pulley cross frame is fixedly connected to the top surface of the pulley vertical frame, and the other end of the pulley vertical frame extends downward; one end of the pulley inclined frame is fixedly connected to the bottom surface of the other end of the pulley cross frame, and the other end of the pulley vertical frame is fixedly connected to the side surface of the pulley vertical frame; a pulley groove is vertically formed in the pulley vertical frame, and the pulley member moves along the direction of the pulley groove;

[0009] The pulley member includes a pulley, a pulley shaft and a nut, the pulley is sleeved on the pulley shaft, and a nut is sleeved on the end of one end of the pulley shaft passing through the pulley groove.

[0010] The axial center of the thruster and the upper vertex of the circumferential surface of the pulley member are on the same horizontal line, and the axes of the flange connecting member, the thrust balance, the intermediate shaft and the thruster are on the same straight line and perpendicular to the top support cross frame.

[0011] A first hook is arranged at the center of the side surface of one side of the thruster facing the pulley frame, and one end of the steel cable is fixedly connected to the first hook; a second hook is arranged at the center of the top surface of the weight rack, and the other end of the steel cable is fixedly connected to the second hook.

[0012] The thrust direction of the thruster is consistent with the pulling direction of the steel cable.

[0013] A calibration method for a calibration device of a thrust balance, the calibration method comprising the following steps:

[0014] Step 1, pulley adjustment step: Adjust the position of the pulley on the pulley bracket so that the upper vertex of the circumferential surface of the pulley is on the same straight line as the axial center of the thruster;

[0015] Step 2, weight rack mounting step: First, fixedly connect one end of the steel cable to the center of the side of one side of the thruster, extend the other end of the steel cable downward after changing the direction through the circumferential surface of the pulley, and then fixedly connect the downward-extended end of the steel cable to the weight rack;

[0016] Step 3, zero value marking step: After the weight rack is mounted on the thruster, zero the voltage value generated by the thrust balance and mark it as the zero value;

[0017] Step 4, load loading step: Gradually increase the weights placed in the weight rack until the total load of the weight rack ≥ the maximum thrust value of the thruster; According to the current load of the weight rack and the voltage, calculate the calibration coefficient of the thruster in sequence, and calculate the fitted output load according to the calibration coefficient;

[0018] Step 5, load unloading step: Gradually decrease the weights loaded on the weight rack in Step 4. According to the current load of the weight rack and the voltage, calculate the calibration coefficient of the thruster in sequence, and calculate the fitted output load according to the calibration coefficient to complete the calibration work.

[0019] Compare the single load in Step 4 and Step 5 with its corresponding single fitted output load. The comparison result is any one of the following:

[0020] The first type: If the difference between the load and the fitted output load < the accuracy difference of the thrust balance, the calibration coefficient is correct;

[0021] The second type: If the difference between any load and the fitted output load ≥ the accuracy difference of the thrust balance, the calibration coefficient is incorrect, and it is necessary to check whether the operation steps are accurate and whether the thrust balance calibration device is correctly installed.

[0022] The load loading step in Step 4 is: Gradually increase the weights placed in the weight rack until the total load of the weight rack ≥ the maximum thrust value of the thruster, and the weight of the weights is greater than or less than the weight of the weights in Step 4; According to the current load of the weight rack and the voltage, calculate the calibration coefficient of the thruster in sequence, and calculate the fitted output load according to the calibration coefficient;

[0023] The load unloading step in Step 5 is: Gradually decrease the weights loaded on the weight rack. According to the current load of the weight rack and the voltage, calculate the calibration coefficient of the thruster in sequence, and calculate the fitted output load according to the calibration coefficient;

[0024] The comparison step is as follows: compare the single load with the corresponding single fitting output load, and the comparison result is any of the following:

[0025] The first case: if the difference between the load and the fitting output load < the accuracy difference of the thrust balance, the calibration coefficient is correct;

[0026] The second case: if the difference between any load and the fitting output load ≥ the accuracy difference of the thrust balance, the calibration coefficient is incorrect, and it is necessary to check whether the operation steps are accurate and whether the thrust balance calibration device is installed correctly.

[0027] The formula used to calculate the calibration coefficient in step 4 is:

[0028] C xx = mV / kgf

[0029] Where: C xx is the calibration coefficient, mV is the voltage, and kgf is the load; where mV = V / 1000.

[0030] The formula used to calculate the fitting output load is:

[0031]

[0032] Where: F x is the fitting output load, C xx is the calibration coefficient, and X is the voltage;

[0033] Where: xv is the lateral unilateral voltage, and yv is the vertical unilateral voltage.

[0034] Compared with the prior art, the beneficial effects of the present invention are:

[0035] 1. In the calibration device for a thrust balance of the present invention, it includes a top support cross frame and a left support frame and a right support frame respectively connected to both ends thereof. A flange connector, a thrust balance, an intermediate shaft, and a thruster are sequentially connected downward below the top support cross frame. A pulley frame is connected to the top support cross frame on one side of the thruster, and a pulley member is movably connected to the pulley frame. One end of a steel cable is fixedly connected to the center of the side surface on one side of the thruster. The other end of the steel cable extends downward after changing direction through the circumferential surface of the pulley member and is fixedly connected to a weight rack, and weights are installed in the weight rack. When this design is applied, the thruster and the thrust balance are fixed by bolts so that they can be replaced. By replacing the matching flange connector and intermediate shaft, they can be connected to the top support cross frame, so that different sizes of thrusters and different models of thrust balances can be applied. Therefore, the present invention can not only perform calibration work, but also has a wide application range for this calibration device.

[0036] 2. In a calibration device for a thrust balance according to the present invention, the steel cable between the thruster and the pulley member is parallel to the top support cross frame, and the steel cable between the pulley member and the weight rack is perpendicular to the top support cross frame. When this design is applied, the weight rack is connected to the thruster through a steel cable, and the load of the weight rack is converted into a tensile force on the thruster through the pulley member. Under the action of a single-sided force, the strain gauges symmetrically arranged on both sides of the vertical center line of the thrust balance form a pair, one is always in tension and the other is always in compression. The force on the thrust balance is constant, improving the accuracy of the thrust balance, thereby improving the calibration accuracy and stability of the calibration device. Therefore, the present invention can not only calibrate the thrust balance, but also has relatively high calibration accuracy and stability.

[0037] 3. In a calibration device for a thrust balance according to the present invention, the calibration method of the calibration device includes steps such as pulley adjustment, weight hanging, zero marking, load loading and load unloading. The calibration coefficient of the thruster is calculated through the load and the voltage of the thrust balance to complete the calibration work, and the load is compared with the fitted output load to verify the accuracy and accuracy of the calibration, improving the accuracy and accuracy of the present calibration device. Therefore, the present invention can not only perform calibration work, but also has relatively high calibration accuracy and accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 is a schematic structural diagram of the present invention.

[0039] Figure 2 is a schematic structural diagram of the pulley frame in the present invention.

[0040] Figure 3 is a data table diagram of Example 2 in the present invention.

[0041] Figure 4 is a data table diagram of Example 4 in the present invention.

[0042] Figure 5 is a schematic structural diagram of the thrust balance in Example 2 of the present invention.

[0043] In the figure: left support frame 1, right support frame 2, top support cross frame 3, flange connector 4, first bolt 41, second bolt 42, third bolt 43, fourth bolt 44, fifth bolt 45, thrust balance 5, intermediate shaft 6, thruster 7, first hook 71, second hook 72, pulley frame 8, pulley cross frame 81, pulley vertical frame 82, pulley inclined frame 83, pulley groove 84, pulley member 9, pulley 91, pulley shaft 92, nut 93, steel cable 10, weight rack 11, weight 111. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0044] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0045] See Figure 1 — Figure 5 A calibration device for a thrust balance, the thrust balance calibration device comprising: a left support frame 1, a right support frame 2 and a top support cross frame 3; one end of the top support cross frame 3 is fixedly connected to the top end of the left support frame 1, and the other end of the top support cross frame 3 is fixedly connected to the top end of the right support frame 2; the middle top surface of the top support cross frame 3 is connected to the top end of a flange connecting member 4 by a first bolt 41, the bottom end of the flange connecting member 4 is connected to the top end of a thrust balance 5 by a second bolt 42, the bottom end of the thrust balance 5 is connected to the top end of an intermediate shaft 6 by a third bolt 43, and the bottom end of the intermediate shaft 6 is connected to the top end of a thruster 7 by a fourth bolt 44; the bottom surface of the top support cross frame 3 is fixedly connected with a pulley frame 8 by a fifth bolt 45, the pulley frame 8 is located on one side of the thruster 7, and the bottom end of the pulley frame 8 is movably connected with a pulley member 9; one end of a steel cable 10 is fixedly connected to the center of the side surface of one side of the thruster 7, the other end of the steel cable 10 extends downward after changing direction through the circumferential surface of the pulley member 9, and the other end of the steel cable 10 is fixedly connected with a weight rack 11, and weights 111 are contained in the weight rack 11;

[0046] The steel cable 10 between the thruster 7 and the pulley member 9 is parallel to the top support cross frame 3, and the steel cable 10 between the pulley member 9 and the weight rack 11 is perpendicular to the top support cross frame 3.

[0047] The pulley frame 8 includes a pulley cross frame 81, a pulley vertical frame 82 and a pulley inclined frame 83; the pulley cross frame 81 is fixedly connected to the bottom surface of the top support cross frame 3 by a fifth bolt 45; the bottom surface of one end of the pulley cross frame 81 is fixedly connected to the top surface of the pulley vertical frame 82, and the other end of the pulley vertical frame 82 extends downward; one end of the pulley inclined frame 83 is fixedly connected to the bottom surface of the other end of the pulley cross frame 81, and the other end of the pulley vertical frame 82 is fixedly connected to the side surface of the pulley vertical frame 82; a pulley groove 84 is vertically formed in the pulley vertical frame 82, and the pulley member 9 moves along the direction of the pulley groove 84;

[0048] The pulley member 9 includes a pulley 91, a pulley shaft 92 and a nut 93, the pulley 91 is sleeved on the pulley shaft 92, and the nut 93 is sleeved on the end portion of one end of the pulley shaft 92 passing through the pulley groove 84.

[0049] The axial center of the thruster 7 and the upper vertex of the circumferential surface of the pulley member 9 are on the same horizontal line, and the axes of the flange connecting member 4, the thrust balance 5, the intermediate shaft 6 and the thruster 7 are on the same straight line and perpendicular to the top support cross frame 3.

[0050] On one side of the thruster 7 facing the pulley frame 8, a first hook 71 is provided at the center of the side surface, and one end of the steel cable 10 is fixedly connected to the first hook 71; at the center of the top surface of the weight frame 11, a second hook 72 is provided, and the other end of the steel cable 10 is fixedly connected to the second hook 72.

[0051] The thrust direction of the thruster 7 is consistent with the pulling direction of the steel cable 10.

[0052] A calibration method for a calibration device of a thrust balance, the calibration method comprising the following steps:

[0053] Step 1, pulley adjustment step: Adjust the position of the pulley member 9 on the pulley frame 8 so that the upper vertex of the circumferential surface of the pulley member 9 and the axial center of the thruster 7 are on the same straight line;

[0054] Step 2, weight frame hanging step: First, fixedly connect one end of the steel cable 10 to the center of the side surface on one side of the thruster 7, extend the other end of the steel cable 10 downward after changing the direction through the circumferential surface of the pulley member 9, and then fixedly connect the downward-extended end of the steel cable 10 to the weight frame 11;

[0055] Step 3, zero value marking step: After the thruster 7 is hung with the weight frame 11, zero the voltage value generated by the thrust balance 5 and mark it as the zero value;

[0056] Step 4, load loading step: Place the weights 111 in the weight frame 11 in sequence until the total load of the weight frame 11 ≥ the maximum thrust value of the thruster 7; according to the current load of the weight frame 11 and the voltage, calculate the calibration coefficient of the thruster 7 in sequence, and calculate the fitted output load according to the calibration coefficient;

[0057] Step 5, load unloading step: Gradually decrease the weights 111 loaded on the weight frame 11 in Step 4, calculate the calibration coefficient of the thruster 7 in sequence according to the current load of the weight frame 11 and the voltage, and calculate the fitted output load according to the calibration coefficient to complete the calibration work.

[0058] The calibration method further includes a comparison step after Step 5, and the comparison step is:

[0059] Compare the single load and its corresponding single fitted output load in Step 4 and Step 5, and the comparison result is any one of the following:

[0060] The first type: If the difference between the load and the fitted output load < the accuracy difference of the thrust balance 5, the calibration coefficient is correct;

[0061] Second type: If the difference between any load and the fitted output load ≥ the accuracy difference of the thrust balance 5, the calibration coefficient is incorrect, and it is necessary to check whether the operation steps are accurate and whether the thrust balance calibration device is correctly installed.

[0062] The load loading step in Step 4 is as follows: Place the weights 111 on the weight rack 11 incrementally until the total load of the weight rack 11 ≥ the maximum thrust value of the thruster 7. The weight of the weight 111 is greater than or less than the weight of the weight in Step 4; Calculate the calibration coefficient of the thruster 7 in sequence according to the current load and voltage of the weight rack 11, and calculate the fitted output load according to the calibration coefficient.

[0063] The load unloading step in Step 5 is as follows: Gradually decrease the weights 111 loaded on the weight rack 11. Calculate the calibration coefficient of the thruster 7 in sequence according to the current load and voltage of the weight rack 11, and calculate the fitted output load according to the calibration coefficient.

[0064] The comparison step is as follows: Compare the single load with its corresponding single fitted output load. The comparison result is any of the following:

[0065] First type: If the difference between the load and the fitted output load < the accuracy difference of the thrust balance 5, the calibration coefficient is correct;

[0066] Second type: If the difference between any load and the fitted output load ≥ the accuracy difference of the thrust balance 5, the calibration coefficient is incorrect, and it is necessary to check whether the operation steps are accurate and whether the thrust balance calibration device is correctly installed.

[0067] The formula used to calculate the calibration coefficient in Step 4 is:

[0068] C xx = mV / kgf

[0069] Where: C xx is the calibration coefficient, mV is the voltage, kgf is the load; where mV = V / 1000.

[0070] The formula used to calculate the fitted output load is:

[0071]

[0072] Where: F x is the fitted output load, C xx is the calibration coefficient, X is the voltage;

[0073] Where: xv is the lateral unilateral voltage, yv is the vertical unilateral voltage.

[0074] The principle of the present invention is described as follows:

[0075] This thrust balance calibration device is calibrated by means of unilateral horizontal loading. Since the thrust balance is mainly used to measure the horizontal axial thrust of the thruster, in order to be consistent with the actual thrust direction of the thruster, it is calibrated in a unilateral horizontal manner, which changes linearly with the increase and decrease of the weight of the weights. Under the action of the unilateral horizontal tension, the thrust balance bears a unidirectional bending moment, improving the stability and service life of the force measuring balance under stress. And the symmetry center of the strain gauges on both sides remains constant, avoiding the situation of poor accuracy and stability and offset of the symmetry center caused by the repeated changes of the strain gauges being pulled and compressed under the bilateral bending moment. This method can make the stress direction and magnitude of the strain gauges on the thrust balance more accurate when the strain gauges are subjected to unilateral horizontal tension, avoiding the influence of the stress on the strain gauges in other directions on their accuracy. At the same time, adopting the method of unilateral calibration, the structure is simpler, the calibration accuracy is higher, and the operation efficiency is higher, which is beneficial to ensuring the accuracy and service life of the force measuring balance calibration.

[0076] Example 1:

[0077] See Figures 1-5 , a calibration device for a thrust balance, the thrust balance calibration device includes: a left support frame 1, a right support frame 2 and a top support cross frame 3; one end of the top support cross frame 3 is fixedly connected to the top end of the left support frame 1, and the other end of the top support cross frame 3 is fixedly connected to the top end of the right support frame 2; the middle top surface of the top support cross frame 3 is connected to the top end of the flange connector 4 through a first bolt 41, and the bottom end of the flange connector 4 is connected to the top end of the thrust balance 5 through a second bolt 42, the bottom end of the thrust balance 5 is connected to the top end of the intermediate shaft 6 through a third bolt 43, and the bottom end of the intermediate shaft 6 is connected to the top end of the thruster 7 through a fourth bolt 44; the bottom surface of the top support cross frame 3 is fixedly connected with a pulley frame 8 through a fifth bolt 45, the pulley frame 8 is located on one side of the thruster 7, and the bottom end of the pulley frame 8 is movably connected with a pulley member 9; one end of a steel cable 10 is fixedly connected to the center of the side surface of one side of the thruster 7, and the other end of the steel cable 10 extends downward after changing direction through the circumferential surface of the pulley member 9, and the other end of the steel cable 10 is fixedly connected with a weight rack 11, and weights 111 are installed in the weight rack 11; the steel cable 10 between the thruster 7 and the pulley member 9 is parallel to the top support cross frame 3, and the steel cable 10 between the pulley member 9 and the weight rack 11 is perpendicular to the top support cross frame 3; preferably, the thrust balance is a three-component thrust balance.

[0078] During application, the thrust balance 5 is fixed on the flange connector 4. The lower end of the thrust balance 5 is successively connected to the intermediate shaft 6 and the thruster 7. Level the thruster 7 so that it is parallel to the thrust balance and the thrust balance is not under force. Keep the axes of the flange connector 4, the thrust balance 5, the intermediate shaft 6 and the thruster 7 on a straight line. Then adjust the position of the pulley member 9 on the pulley frame 8 so that the upper vertex of the circumferential surface of the pulley member 9 and the axial center of the thruster 7 are on a horizontal line. Then fix one end of the steel cable 10 to the center of one side surface of the thruster 7. The other end of the steel cable 10 extends downward after changing direction through the circumferential surface of the pulley member, and a weight rack is hung on the downward extending end. Check that the horizontal and vertical directions of the steel cable 10 are at a right angle, thus completing the installation of the device before calibration.

[0079] Embodiment 2:

[0080] The basic content is the same as that of Embodiment 1, and the differences are as follows:

[0081] After the installation of the calibration device is completed, calibrate the thrust balance according to a calibration method of a calibration device for a thrust balance. The calibration method includes the following steps:

[0082] Step 1. Pulley member adjustment step: Adjust the position of the pulley member 9 on the pulley frame 8 so that the upper vertex of the circumferential surface of the pulley member 9 and the axial center of the thruster 7 are on a straight line;

[0083] Step 2. Weight rack hanging step: First, fix one end of the steel cable 10 to the center of one side surface of the thruster 7. Let the other end of the steel cable 10 extend downward after changing direction through the circumferential surface of the pulley member 9, and then fix the downward extending end of the steel cable 10 to the weight rack 11;

[0084] Step 3. Zero value marking step: After the thruster 7 is hung with the weight rack 11, due to the weight of the weight rack 11 itself, the thrust balance 3 will generate a small voltage. To ensure the calibration accuracy, the voltage value generated by the thrust balance 5 needs to be reset to zero and marked as the zero value; in practice, according to the size of the thruster and the accuracy of the thrust balance, this step can also be ignored;

[0085] Step 4. Load loading step: Place the weights 111 into the weight rack 11 successively in increasing order. There is no fixed standard for the weight of the weights placed each time. In this embodiment, they are increased by 100 kg in sequence, and the upper limit of the increase is the upper limit of the thrust of the thruster;

[0086] According to the size of the thruster, the diameter of the steel cable needs to be adjusted as required, which will not be elaborated here;

[0087] The forces and moments generated by the load on the thrust balance will cause displacements and deformations of the strain gauges on the thrust balance. The displacements and deformations of the strain gauges will cause voltage changes. The three-component thrust balance has 4 strain gauges. As Figure 5 shown, since this calibration device is a single-sided force, theoretically only the x strain gauges on the single-sided force-bearing direction will generate voltage. Limited by the accuracy, a small voltage will also be generated in the single-sided y direction;

[0088] According to the current load of the weight rack 11 and the voltage, as Figure 3 shown, the calibration coefficient of the thruster 7 can be calculated in sequence, and the fitted output load can be calculated according to the calibration coefficient;

[0089] Step Five: Load unloading step: Gradually decrease the weights 111 loaded on the weight rack 11 in Step Four. According to the current load of the weight rack 11 and the voltage, as Figure 3 shown, the calibration coefficient of the thruster 7 can be calculated in sequence, and the fitted output load can be calculated according to the calibration coefficient to complete the calibration work.

[0090] Preferably, the formula used to calculate the calibration coefficient is:

[0091] C xx = mV / kgf

[0092] where: C xx is the calibration coefficient, mV is the voltage, and kgf is the load; where mV = V / 1000.

[0093] Example 3:

[0094] The basic content is the same as that of Example 2, except that:

[0095] Compare the single load in Step Four and Step Five with its corresponding single fitted output load. The comparison results are any of the following:

[0096] The first type: If the difference between the load and the fitted output load < the accuracy difference of the thrust balance 5, the calibration coefficient is correct;

[0097] The second type: If the difference between any load and the fitted output load ≥ the accuracy difference of the thrust balance 5, the calibration coefficient is incorrect, and factors that may affect the accuracy such as whether the operation steps are accurate, whether the thrust balance calibration device is installed correctly, and whether the thrust balance is damaged should be checked.

[0098] Preferably, the formula used to calculate the fitted output load is:

[0099]

[0100] where: F x is the fitted output load, C xxis the calibration coefficient, and X is the voltage;

[0101] Wherein: xv is the lateral unilateral voltage, and yv is the vertical unilateral voltage.

[0102] Example 4:

[0103] The basic content is the same as that of Example 3, and the difference is:

[0104] In order to verify whether the error range between the load and the fitted output load is within the accuracy difference range of the thrust balance 5, the weight of the weights can be adjusted to perform calibration again. The accuracy difference of the thrust balance used in this example is 3%.

[0105] The load loading step in Step 4 is: Place the weights 111 incrementally in the weight rack 11 until the total load of the weight rack 11 ≥ the maximum thrust value of the thruster 7. The weight of the weight 111 is greater than or less than the weight of the weights in Step 4; According to the current load and voltage of the weight rack 11, calculate the calibration coefficient of the thruster 7 in sequence, and calculate the fitted output load according to the calibration coefficient, as Figure 4 shown;

[0106] The load unloading step in Step 5 is: Gradually decrease the weights 111 loaded on the weight rack 11. According to the current load and voltage of the weight rack 11, calculate the calibration coefficient of the thruster 7 in sequence, and calculate the fitted output load according to the calibration coefficient;

[0107] The comparison step is: Compare the single load with its corresponding single fitted output load. The difference between the load and the fitted output load < the accuracy difference of the thrust balance 5, which is 3%, and the calibration coefficient is correct.

[0108] The above is only the preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiment. Any equivalent modification or change made by those of ordinary skill in the art according to the disclosure of the present invention shall be included in the protection scope recorded in the claims.

Claims

1. A calibration device for a thrust balance, characterized in that, The described thrust balance calibration device includes: a left support frame (1), a right support frame (2), and a top support cross-frame (3); one end of the top support cross-frame (3) is fixedly connected to the top end of the left support frame (1), and the other end of the top support cross-frame (3) is fixedly connected to the top end of the right support frame (2); the top surface of the middle part of the top support cross-frame (3) is connected to the top end of the flange connector (4) through a first bolt (41), the bottom end of the flange connector (4) is connected to the top end of the thrust balance (5) through a second bolt (42), the bottom end of the thrust balance (5) is connected to the top end of the intermediate shaft (6) through a third bolt (43), and the bottom end of the intermediate shaft (6) is connected to the top end of the thruster (7) through a fourth bolt (44); a pulley frame (8) is fixedly connected to the bottom surface of the top support cross-frame (3) through a fifth bolt (45), the pulley frame (8) is located on one side of the thruster (7), and the bottom end of the pulley frame (8) is movably connected to a pulley member (9); one end of a steel cable (10) is fixedly connected to the center of the side surface of one side of the thruster (7), the other end of the steel cable (10) extends downward after changing direction through the circumferential surface of the pulley member (9), and the other end of the steel cable (10) is fixedly connected to a weight frame (11), and weights (111) are contained in the weight frame (11). The steel cable (10) between the thruster (7) and the pulley member (9) is parallel to the top support cross-frame (3), and the steel cable (10) between the pulley member (9) and the weight frame (11) is perpendicular to the top support cross-frame (3).

2. The calibration device for a thrust balance according to claim 1, characterized in that: The pulley frame (8) includes a pulley cross-frame (81), a pulley vertical frame (82), and a pulley inclined frame (83); the pulley cross-frame (81) is fixedly connected to the bottom surface of the top support cross-frame (3) through a fifth bolt (45); the bottom surface of one end of the pulley cross-frame (81) is fixedly connected to the top surface of the pulley vertical frame (82), and the other end of the pulley vertical frame (82) extends downward; one end of the pulley inclined frame (83) is fixedly connected to the bottom surface of the other end of the pulley cross-frame (81), and the other end of the pulley inclined frame (83) is fixedly connected to the side surface of the pulley vertical frame (82); a pulley groove (84) is vertically formed on the pulley vertical frame (82), and the pulley member (9) moves along the direction of the pulley groove (84). The pulley member (9) includes a pulley (91), a pulley shaft (92), and a nut (93), the pulley (91) is sleeved on the pulley shaft (92), and a nut (93) is sleeved on the end of one end of the pulley shaft (92) passing through the pulley groove (84).

3. The calibration device for a thrust balance according to claim 2, characterized in that: The axial center of the thruster (7) and the upper vertex of the circumferential surface of the pulley member (9) are on the same horizontal line, and the axes of the flange connector (4), the thrust balance (5), the intermediate shaft (6), and the thruster (7) are on the same straight line and are perpendicular to the top support cross-frame (3).

4. The calibration device for a thrust balance according to claim 3, characterized in that: On one side of the thruster (7) facing the pulley frame (8), a first hook (71) is provided at the center of the side surface, and one end of the steel cable (10) is fixedly connected to the first hook (71); at the center of the top surface of the weight rack (11), a second hook (72) is provided, and the other end of the steel cable (10) is fixedly connected to the second hook (72).

5. The calibration device for a thrust balance according to any one of claims 1-4, characterized in that: The thrust direction of the thruster (7) is consistent with the pulling direction of the steel cable (10).

6. A calibration method for the calibration device for a thrust balance according to claim 1, characterized in that, The calibration method includes the following steps: Step 1. Pulley adjustment step: Adjust the position of the pulley member (9) on the pulley frame (8) so that the upper vertex of the circumferential surface of the pulley member (9) and the axial center of the thruster (7) are on the same straight line. Step 2. Weight rack mounting step: First, fixedly connect one end of the steel cable (10) to the center of the side surface of one side of the thruster (7), let the other end of the steel cable (10) extend downward after changing the direction through the circumferential surface of the pulley member (9), and then fixedly connect the downward extending end of the steel cable (10) to the weight rack (11). Step 3. Zero value marking step: After the thruster (7) is mounted with the weight rack (11), zero the voltage value generated by the thrust balance (5) and mark it as the zero value. Step 4. Load loading step: Gradually increase and place weights (111) into the weight rack (11) until the total load of the weight rack (11) ≥ the maximum thrust value of the thruster (7); according to the current load of the weight rack (11) and the voltage, calculate the calibration coefficient of the thruster (7) in sequence, and calculate the fitting output load according to the calibration coefficient. Step 5. Load unloading step: Gradually decrease the weights (111) loaded on the weight rack (11) in Step 4. According to the current load of the weight rack (11) and the voltage, calculate the calibration coefficient of the thruster (7) in sequence, and calculate the fitting output load according to the calibration coefficient to complete the calibration work.

7. The calibration method for the calibration device for a thrust balance according to claim 6, characterized in that, The calibration method further includes a comparison step after Step 5, and the comparison step is: Compare the single load and its corresponding single fitting output load in Step 4 and Step 5, and the comparison result is any one of the following: The first type: If the difference between the load and the fitting output load < the accuracy difference of the thrust balance (5), the calibration coefficient is correct. The second type: If the difference between any load and the fitting output load ≥ the accuracy difference of the thrust balance (5), the calibration coefficient is incorrect, and it is necessary to check whether the operation steps are accurate and whether the thrust balance calibration device is correctly installed.

8. The calibration method for the calibration device for a thrust balance according to claim 7, characterized in that: The load loading step in Step 4 is: Gradually increase and place weights (111) into the weight rack (11) until the total load of the weight rack (11) ≥ the maximum thrust value of the thruster (7), and the weight of the weight (111) is greater than or less than the weight of the weight in Step 4; according to the current load of the weight rack (11) and the voltage, calculate the calibration coefficient of the thruster (7) in sequence, and calculate the fitting output load according to the calibration coefficient. The load unloading step in the fifth step is as follows: Gradually decrease the weights (111) loaded on the weight rack (11). According to the current load of the weight rack (11) and the voltage, calculate the calibration coefficient of the thruster (7) in sequence, and calculate the fitted output load according to the calibration coefficient. The comparison step is as follows: Compare the single load with its corresponding single fitted output load. The comparison result is any one of the following: The first type: If the difference between the load and the fitted output load < the accuracy difference of the thrust balance (5), the calibration coefficient is correct. The second type: If the difference between any load and the fitted output load ≥ the accuracy difference of the thrust balance (5), the calibration coefficient is incorrect, and it is necessary to check whether the operation steps are accurate and whether the thrust balance calibration device is correctly installed.

9. The calibration method for the calibration device for a thrust balance according to claim 6, 7 or 8, characterized in that, The formula used to calculate the calibration coefficient in the fourth step is: C xx = mV / kgf Where: C xx is the calibration coefficient, mV is the voltage, kgf is the load; where mV = V / 1000.

10. A calibration method for a calibration device of a thrust balance according to claim 6, 7 or 8, characterized in that, The formula used to calculate the fitted output load is: Where: F x is the fitted output load, C xx is the calibration coefficient, and X is the voltage; Wherein: xv is the lateral unilateral voltage, and yv is the vertical unilateral voltage.

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