Torque standard machine capable of reducing torque measurement error

Abstract

The invention provides a torque standard machine capable of reducing torque measurement errors. The torque standard machine comprises a base, a lever supporting seat, a balance driving mechanism and a lever stress application mechanism. In the two ends of the tested torque device connected with the balance driving mechanism and the lever, one end adopts a rigid coupling, and the other end adopts a ball tooth coupling. According to the invention, a connection mode of the rigid coupling at one end and the spherical tooth coupling at the other end is adopted, the rigid coupling can ensure the coaxiality of the tested torque device and the butt joint end, and the spherical tooth coupling at the other end can compensate the coaxiality deviation of the tested torque device and the butt joint end; the axial deviation of the rotation connecting shaft of the lever and the axial deviation of the output shaft of the balance driving mechanism are compensated, a mode of combining the rigid coupling and the spherical gear coupling is adopted, the detected torque device cannot sink due to the influence of gravity, and the accuracy of torque detection is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of metrology, and particularly to a torque standard machine for reducing torque measurement errors. Background Art

[0002] The lever-type torque standard machine is a type of standard machine capable of measuring large torques. The common one is the deadweight-type torque standard machine, which uses the gravity of weights as the standard load and generates the standard torque after being amplified by the lever mechanism. Limited by the volume of the weights, and a large number of standard weights need to be configured, resulting in high costs and large occupied space. With the development and progress of technology, currently, there is a method of applying the standard load by using a force application mechanism and a high-precision force sensor at the end of the lever. Since no weights are required, it is more convenient to use and the occupied space is significantly reduced. This type of torque standard machine is gradually widely used.

[0003] Due to the existence of errors in the mechanical processing and assembly processes, on the torque standard machine, the axis of the lever's rotary connecting shaft and the axis of the output shaft of the balance drive mechanism cannot be completely coaxial. The measured torque device is conventionally connected to the balance drive mechanism and the lever by an elastic coupling to compensate for the axis deviation and ensure the continuity and stability of torque transmission. However, when using the elastic coupling connection method, it sinks under the influence of the gravity of the measured torque device, resulting in a large deviation between the axis of the measured torque device and the axes of the lever's rotary connecting shaft and the output shaft of the balance drive mechanism, thereby affecting the torque detection accuracy.

[0004] In addition, for the torque standard machine that uses a force application mechanism and a high-precision force sensor to apply the standard load, due to the limited range of the high-precision force sensor, the torque range that this type of torque standard machine can measure is relatively narrow. Directly configuring torque standard machines with multiple ranges is costly. If the torque range is changed by replacing force sensors with different ranges, it needs to be recalibrated, which takes a long time. Summary of the Invention

[0005] In order to overcome the deficiencies of the above-mentioned prior art, the purpose of the present invention is to provide a torque standard machine for reducing torque measurement errors.

[0006] To achieve the above purpose, the technical solution adopted by the present invention to solve its technical problems is: a torque standard machine for reducing torque measurement errors, including:

[0007] A base;

[0008] A lever support seat, which is installed in the middle of the base;

[0009] A lever, which is installed on the lever support seat through a linear fulcrum;

[0010] A balance drive mechanism, which is located on the side of the lever and is used to keep the lever in a horizontal balance state;

[0011] A lever force - adding mechanism, which is used to apply a force to the end of the lever;

[0012] In the two - end connections where the torque - measuring device is connected to the balance drive mechanism and the lever, one end uses a rigid coupling and the other end uses a ball - tooth coupling; the rigid coupling includes a metal coupling body with an integral structure, a coupling hole is provided through the center of the metal coupling body, a first slit extending radially outward from the coupling hole is further provided on the metal coupling body, a circumferentially - arranged dividing slit is provided in the middle of the metal coupling body, and the arc length of the dividing slit is half a circumference; the ball - tooth coupling includes a first connecting shaft and a second connecting shaft, a ball head is provided at one end of the first connecting shaft, external arc teeth are provided on the ball head, a coupling hole is provided at the other end of the first connecting shaft, a hemispherical cavity is provided at one end of the second connecting shaft, and internal arc teeth meshing with the external arc teeth are provided on the cavity wall of the cavity, and a coupling hole is provided at the other end of the second connecting shaft.

[0013] The present invention adopts a connection method with a rigid coupling at one end and a ball - tooth coupling at the other end. The rigid coupling can ensure the coaxiality between the torque - measuring device and the docking end, and the ball - tooth coupling at the other end can compensate for the coaxiality deviation between the torque - measuring device and the docking end, and compensate for the axis deviation between the axis of the lever's rotary connecting shaft and the output shaft of the balance drive mechanism. By combining the rigid coupling and the ball - tooth coupling, the torque - measuring device will not sink due to the influence of gravity, improving the accuracy of torque detection.

[0014] Further, the lever force - adding mechanism includes a blade module, a knife bearing module, a force sensor module, a first pull - frame, and a force - applying mechanism; the blade module is fixedly installed on the upper surface of the lever end, the blade module includes a blade block, and the upper part of the blade block has a convex V - shaped blade portion; the knife bearing module includes a knife bearing block, the lower surface of the knife bearing block has a concave V - shaped knife bearing groove, the knife bearing block is pressed above the blade block, and the V - shaped blade portion is in linear contact with the V - shaped knife bearing groove; the force sensor module is installed above the knife bearing module, the upper beam of the first pull - frame is pressed above the force sensor module, and the force - applying mechanism applies a downward pulling force to the lower seat of the first pull - frame through a connecting member; the force sensor module includes n force sensors with different ranges, n - 1 elastic devices, and n - 1 limit blocks, where n≥2, the first force sensor to the nth force sensor are distributed from top to bottom in sequence and the maximum range values increase in sequence, the nth force sensor is installed on the upper surface of the knife bearing module, 1 elastic device is installed above each of the first to the n - 1th force sensors, 1 limit block is installed below each of the first to the n - 1th force sensors, and a stop surface is provided on the upper beam of the first pull - frame corresponding to the position of each limit block. When the force value applied to the force sensor module by the force - applying mechanism through the first pull - frame is greater than or equal to the maximum set force value of the n - 1th force sensor, the limit block below the n - 1th force sensor is pressed against the corresponding stop surface on the upper beam..

[0015] With the above - mentioned preferred solution, the lever force - adding mechanism at the lever end uses multiple force sensors with different ranges and elastic devices connected in series in sequence. As the applied force value increases, the shrinkage amount of the elastic device under force gradually increases. When the force sensor with a smaller force value reaches the upper limit of its measurement range, the upper beam of the first pull - frame contacts the corresponding limit block, and then the force value applied is measured by the next force sensor with a larger force value, thereby expanding the torque range of the torque measurement device. The measured values in different range segments are measured by high - precision force sensors in the corresponding range segments, ensuring the measurement accuracy. The force sensor module is arranged in a top - mounted manner above the knife bearing module, ensuring that the linear contact position of the force applied at the lever end remains constant, ensuring the stability of the lever arm value, and improving the accuracy of the torque standard value.

[0016] Further, the elastic device includes an outer sleeve, a disc spring assembly, and an inner guide post. The upper beam is provided with a hole body matching the outer sleeve, the outer sleeve can move axially up and down along the corresponding hole body of the upper beam, the upper end of the outer sleeve is open, the disc spring assembly and the inner guide post are both located in the inner cavity of the outer sleeve and can move up and down, the lower end of the disc spring assembly abuts against the inner cavity bottom surface of the outer sleeve, and the upper end of the disc spring assembly abuts against the lower end surface of the inner guide post.

[0017] Further, the disc spring assembly includes multiple groups of disc spring small units. The number of disc springs included in each group of disc spring small units is the same. The disc springs in the same disc spring small unit face the same direction, and the adjacent disc spring small units face in opposite directions.

[0018] With the above preferred solution, using disc springs as elastic devices facilitates the selection of appropriate elastic deformation coefficients and the height of the elastic devices, and the axial movement position is relatively stable, ensuring the stability of the lever force application process.

[0019] Further, a lifting guide post is provided in the upper beam of the first pull frame. 2*(n - 1) lifting plates are installed on the lifting guide post in a vertically movable manner. Each lifting plate is correspondingly provided with a lifting drive mechanism for driving its up and down movement. An opening is provided at the middle position of each lifting plate; from top to bottom, guide sleeves are detachably and fixedly installed at the middle openings of the 1st, 3rd... 2n - 1st lifting plates. The (n - 1)th elastic device is installed in the guide sleeve on the 2n - 1st lifting plate and can move axially up and down along the guide sleeve; from top to bottom, stop rings are detachably and fixedly installed at the middle openings of the 2nd, 4th... 2n - 2nd lifting plates. A stop surface is provided on the lower surface of the stop ring. When the force value applied by the force application mechanism to the force sensor module through the first pull frame is greater than or equal to the maximum set force value of the (n - 1)th force sensor, the limit stop block below the (n - 1)th force sensor presses against the stop surface of the stop ring on the 2n - 2nd lifting plate.

[0020] With the above preferred solution, by using the lifting plates with adjustable height positions to carry and install the guide sleeves and stop rings, it is convenient to adjust the maximum measurement value during the range switching of each force sensor, facilitating the maximum utilization of the high-precision measurement ranges of each force sensor, and thus improving the accuracy of torque measurement. At the same time, to adapt to different sizes and models of elastic devices and force sensors, only the appropriate guide sleeves and stop rings need to be replaced, without customizing and processing the upper beam with a specific size structure, improving the commonality of the first pull frame and reducing the manufacturing cost.

[0021] Further, a first rotary connection shaft is fixedly installed on one side surface of the lever, and a second rotary connection shaft is fixedly installed on the other side surface of the lever. The axes of the first rotary connection shaft and the second rotary connection shaft are both collinear with the linear fulcrum; the balance drive mechanism includes a first balance drive mechanism and a second balance drive mechanism. The first balance drive mechanism is located on one side of the lever, and the output shaft of the first balance drive mechanism is coaxially arranged with the first rotary connection shaft. The second balance drive mechanism is located on the other side of the lever, and the output shaft of the second balance drive mechanism is coaxially arranged with the second rotary connection shaft. The rated output torque of the second balance drive mechanism is greater than the rated output torque of the first balance drive mechanism.

[0022] With the above preferred solution, balance driving mechanisms are respectively arranged on both sides of the lever, and the rated output torques of the two balance driving mechanisms are different. The device to be measured for torque can be installed between the output shaft of the first balance driving mechanism and the first rotary connection shaft of the lever, or can be installed between the output shaft of the second balance driving mechanism and the second rotary connection shaft of the lever. During measurement, a suitable balance driving mechanism is selected according to the torque measurement range of the device to be measured for torque, which can respond more accurately to minute changes and improve the measurement sensitivity and measurement accuracy.

[0023] Furthermore, two parallel linear guide rails and a rack located between the two linear guide rails are respectively provided on the bases on both sides of the lever; a first frame is slidably installed on the linear guide rail on one side of the lever, the first balance driving mechanism is fixedly installed on the first frame, and a first reduction motor is further provided on the first frame, and a gear meshing with the rack is installed on the output shaft of the first reduction motor; a second frame is slidably installed on the linear guide rail on the other side of the lever, the second balance driving mechanism is fixedly installed on the second frame, and a second reduction motor is further provided on the second frame, and a gear meshing with the rack is installed on the output shaft of the second reduction motor.

[0024] With the above preferred solution, it is convenient to perform axial translation of the balance driving mechanism to facilitate the installation of the device to be measured for torque.

[0025] Furthermore, a first support unit is slidably installed on the linear guide rail between the first frame and the lever, and a second support unit is slidably installed on the linear guide rail between the second frame and the lever. Both the first support unit and the second support unit include a support base, a support platform and a platform lifting driving mechanism. A third reduction motor is provided on the support base, and a gear meshing with the rack is installed on the output shaft of the third reduction motor. The support platform is slidably installed on the support base via a vertically arranged guide post. Two worm gear lifts distributed left and right are further installed on the support base. The two worm gear lifts are respectively connected to the output shaft of a double-output shaft reduction motor via couplings. The double-output shaft reduction motor drives the worm gear lifts to drive the support platform to move up and down. Multiple T-shaped grooves are provided on the support platform at intervals.

[0026] With the above preferred solution, the support unit can be translated along the linear guide rail and the support platform can be adjusted in height, which is convenient for supporting devices such as torque wrenches during measurement. An auxiliary fixture can be installed on the support platform to facilitate the loading and unloading of torque devices during testing. Description of the Drawings

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0028] Figure 1 It is a schematic structural diagram of an embodiment of the torque standard machine of the present invention.

[0029] Figure 2 It is a left view of an embodiment of the torque standard machine of the present invention.

[0030] Figure 3 It is Figure 2 A sectional view taken along the A-A direction in

[0031] Figure 4 It is a schematic structural diagram of an embodiment of the force sensor module.

[0032] Figure 5 It is a bottom view of an embodiment of the upper beam.

[0033] Figure 6 It is Figure 5 A sectional view taken along the B-B direction in

[0034] Figure 7 It is a schematic structural diagram of an embodiment of the elastic device.

[0035] Figure 8 It is a schematic structural diagram of an installation method of a force sensor module including two force sensors with different ranges in the upper beam.

[0036] Figure 9 It is a schematic structural diagram of an installation method of a force sensor module including three force sensors with different ranges in the upper beam.

[0037] Figure 10 It is Figure 9 A partial enlarged view at C in

[0038] Figure 11 It is a top view of an embodiment of the torque standard machine.

[0039] Figure 12 It is Figure 11 A sectional view taken along the D-D direction in

[0040] Figure 13 It is Figure 11 A sectional view taken along the E-E direction in

[0041] Figure 14 It is a schematic structural diagram of the connection of the device under test torque on the torque standard machine.

[0042] Figure 15 It is a schematic structural diagram of an embodiment of a rigid coupling.

[0043] Figure 16 It is a schematic structural diagram of an embodiment of a ball tooth coupling.

[0044] The names of the corresponding components represented by the numbers and letters in the figure:

[0045] 10 - Base; 11 - Linear guide rail; 12 - Rack; 20 - Lever support seat; 30 - Lever; 31 - First rotary connecting shaft; 32 - Second rotary connecting shaft; 41 - First balance driving mechanism; 411 - First frame; 42 - Second balance driving mechanism; 421 - Second frame; 422 - Second reduction motor; 50 - First lever force applying mechanism; 51 - Blade module; 510 - Blade block; 511 - V-shaped blade part; 52 - Knife bearing module; 520 - Knife bearing block; 521 - V-shaped knife bearing groove; 53 - Force sensor module; 531 - Force sensor; 532 - Elastic device; 5321 - Outer sleeve; 5322 - Disc spring combination; 5323 - Inner guide post; 5324 - Ball; 5325 - Spherical indenter; 5326 - Thrust bolt; 5327 - Pull rod nail; 533 - Limit stop block; 5331 - Outer conical surface; 54 - First pulling frame; 541 - Upper beam; 542 - Lower seat; 543 - Support column; 55 - Force applying mechanism; 56 - Second pulling frame; 561 - Upper beam; 562 - Lower seat; 61 - Lifting guide post; 62 - Lifting plate; 63 - Lifting driving mechanism; 64 - Guide sleeve; 641 - Stop part; 65 - Stop ring; 651 - Stop surface; 652 - Inner conical surface; 70 - Second lever force applying mechanism; 81 - First support unit; 811 - Support seat; 812 - Support platform; 8121 - T-shaped groove; 813 - Platform lifting driving mechanism; 8131 - Guide post; 8132 - Worm gear lift; 8133 - Double output shaft reduction motor; 814 - Third reduction motor; 82 - Second support unit; 91 - Rigid coupling; 911 - Metal coupling body; 912 - Coupling hole; 913 - First gap; 914 - Partition seam; 92 - Ball tooth coupling; 921 - First connecting shaft; 9211 - Ball head; 9212 - Outer arc teeth; 922 - Second connecting shaft; 9221 - Concave cavity; 9222 - Inner arc teeth. Specific embodiments

[0046] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0047] As shown Figures 1 - 16 in the figure, an embodiment of the present invention is: a torque standard machine for reducing torque measurement error, comprising:

[0048] a base 10;

[0049] a lever support 20, which is installed in the middle of the base 10;

[0050] a lever 30, which is installed on the lever support 20 so as to be swingable left and right through a linear fulcrum;

[0051] a lever force applying mechanism, which is used to apply a force to the end of the lever 30;

[0052] a balance driving mechanism, which is located on the side of the lever 30 and is used to keep the lever in a horizontal balance state;

[0053] In the connection of the two ends of the device under test torque connected to the balance driving mechanism and the lever, one end uses a rigid coupling 91 and the other end uses a ball tooth coupling 92. The rigid coupling 91 includes a metal coupling body 911 of an integral structure. A coupling hole 912 is provided through the center of the metal coupling body 911. A first slit 913 extending radially outward from the coupling hole is also provided on the metal coupling body 911. A circumferentially arranged dividing slit 914 is provided in the middle of the metal coupling body 911. The arc length of the dividing slit 914 is half a circumference. Locking bolts for locking after the rigid coupling is connected to the object shaft are respectively provided at both ends of the dividing slit 914. The ball tooth coupling 92 includes a first connecting shaft 921 and a second connecting shaft 922. A ball head 9211 is provided at one end of the first connecting shaft 921. External arc teeth 9212 are provided on the ball head 9211. A coupling hole is provided at the other end of the first connecting shaft 921. A hemispherical cavity 9221 is provided at one end of the second connecting shaft 922. Internal arc teeth 9222 meshing with the external arc teeth 9212 are provided on the cavity wall of the cavity 9221. A coupling hole is provided at the other end of the second connecting shaft 922.

[0054] The beneficial effects of adopting the above technical solutions are: adopting the connection method of a rigid coupling at one end and a ball tooth coupling at the other end, the rigid coupling can ensure the coaxiality between the device under test torque and the docking end, and the ball tooth coupling at the other end can compensate for the coaxiality deviation between the device under test torque and the docking end, and compensate for the axis deviation between the axis of the lever rotary connecting shaft and the output shaft of the balance driving mechanism. By combining the rigid coupling and the ball tooth coupling, the device under test torque will not sink due to the influence of gravity, improving the accuracy of torque detection.

[0055] As Figures 1 - 13As shown in the figure, in some other embodiments of the present invention, the lever force adding mechanism includes a blade module 51, a knife bearing module 52, a force sensor module 53, a first bracket 54, and a force applying mechanism 55; the blade module 51 is fixedly installed on the upper surface of the end of the lever 30, and the blade module 51 includes a blade block 510, and the upper part of the blade block 510 has a convex V-shaped blade part 511; the knife bearing module 52 includes a knife bearing block 520, and the lower surface of the knife bearing block 520 has a concave V-shaped knife bearing groove 521. The knife bearing block 520 is pressed above the blade block 510, and the V-shaped blade part 511 is in linear contact with the V-shaped knife bearing groove 521; the force sensor module 53 is installed above the knife bearing module 52, the upper beam 541 of the first bracket 54 is pressed above the force sensor module 53, and the force applying mechanism 55 applies a downward pulling force to the lower seat 542 of the first bracket 54 through a connecting member; the force sensor module 53 includes n force sensors 531 with different measuring ranges, n-1 elastic devices 532, and n-1 limit blocks 533, where n≥2. The first force sensor 531 to the nth force sensor 531 are distributed from top to bottom in sequence and the maximum measuring range values increase in sequence. The nth force sensor 531 is installed on the upper surface of the knife bearing module 52. One elastic device 532 is installed above each of the first to n-1th force sensors 531, and one limit block 533 is installed below each of the first to n-1th force sensors 531. A stop surface 651 is provided on the upper beam 541 of the first bracket at the position corresponding to each limit block 533. When the force value applied by the force applying mechanism 55 to the force sensor module 53 through the first bracket 54 is greater than or equal to the maximum set force value of the n-1th force sensor 531, the limit block 533 below the n-1th force sensor 531 is pressed against the corresponding stop surface 651 on the upper beam. The beneficial effects of adopting the above technical solution are as follows: The lever force adding mechanism at the end of the lever uses multiple force sensors with different measuring ranges and elastic devices connected in series in sequence. As the applied force value increases, the contraction amount of the elastic device under force gradually increases. When the force sensor with a smaller force value reaches the upper limit of the measuring range, the upper beam of the first bracket contacts the corresponding limit block, and then the force value applied is measured by the next force sensor with a larger force value, thereby expanding the torque measuring range of the torque measuring device. The measured values in different measuring range segments are measured by high-precision force sensors in the corresponding measuring range segments, ensuring the measurement accuracy. The force sensor module is arranged in a top-mounted manner above the knife bearing module, ensuring that the linear contact position of the force applied at the end of the lever remains constant, ensuring the stability of the lever arm value, and improving the accuracy of the torque standard value.

[0056] As Figures 1 - 13As shown, in some other embodiments of the present invention, a first rotary connection shaft 31 is fixedly installed on one side surface of the lever 30, and a second rotary connection shaft 32 is fixedly installed on the other side surface of the lever 30. The axes of the first rotary connection shaft 31 and the second rotary connection shaft 32 are both collinear with the linear fulcrum; the lever force adding mechanism includes a first lever force adding mechanism 50 and a second lever force adding mechanism 70. The first lever force adding mechanism 50 applies a force to one end of the lever 30, and the second lever force adding mechanism 70 applies a force to the other end of the lever 30; the balance driving mechanism includes a first balance driving mechanism 41 and a second balance driving mechanism 42; the first balance driving mechanism 41 is located on one side of the lever 30, and the output shaft of the first balance driving mechanism 41 is coaxially arranged with the first rotary connection shaft 31; the second balance driving mechanism 42 is located on the other side of the lever 30, and the output shaft of the second balance driving mechanism 42 is coaxially arranged with the second rotary connection shaft 32; the output shaft of the second balance driving mechanism is coaxially arranged with the second rotary connection shaft, and the rated output torque of the second balance driving mechanism is greater than the rated output torque of the first balance driving mechanism. The beneficial effect of adopting the above technical solution is that balance driving mechanisms are respectively arranged on both sides of the lever, and the rated output torques of the two balance driving mechanisms are different. The torque measuring device to be measured can be installed between the output shaft of the first balance driving mechanism and the first rotary connection shaft of the lever, or can be installed between the output shaft of the second balance driving mechanism and the second rotary connection shaft of the lever. During measurement, a suitable balance driving mechanism is selected according to the torque measurement range of the torque measuring device to be measured, which can respond more accurately to minute changes and improve the measurement sensitivity and measurement accuracy.

[0057] As Figure 2 , Figure 3 shown, in some other embodiments of the present invention, a second pulling frame 56 is further included. The upper beam 561 of the second pulling frame 56 is pressed against the top surface of the support column 543 on the upper surface of the lower seat 542 of the first pulling frame 54 through a spherical pressing head, and the lower seat 562 of the second pulling frame 56 is connected to the force applying mechanism 55 through a spherical joint connector. The beneficial effect of adopting the above technical solution is that when it is necessary to measure the force value device, the support column can be taken out and replaced with the force value device to be measured, so that one machine can be used for multiple purposes. When it is necessary to calibrate the standard force sensor, the support column can be taken out and replaced with a standard force sensor with higher accuracy, which is convenient for in-situ calibration of the standard force sensor in the force sensor module.

[0058] As Figure 7 , Figure 8As shown in the figure, in some other embodiments of the present invention, the elastic device 532 includes an outer sleeve 5321, a disc spring combination 5322, and an inner guide post 5323. A hole body matching the outer sleeve 5321 is provided on the upper beam. The outer sleeve 5321 can move axially up and down along the corresponding hole body of the upper beam. The upper end of the outer sleeve 5321 is open. The disc spring combination 5322 and the inner guide post 5323 are both located in the inner cavity of the outer sleeve 5321 and can move up and down. The lower end of the disc spring combination 5322 abuts against the bottom surface of the inner cavity of the outer sleeve 5321, and the upper end of the disc spring combination 5322 abuts against the lower end surface of the inner guide post 5323. The disc spring combination 5322 includes multiple groups of disc spring small units. The number of disc springs included in each group of the disc spring small units is the same. The disc springs in the same disc spring small unit face the same direction, and the directions of adjacent disc spring small units are opposite. The beneficial effect of adopting the above technical solution is that: using disc springs as elastic devices is convenient for selecting appropriate elastic deformation coefficients and the height of the elastic device, and the axial movement position is relatively stable, ensuring the stability of the lever force application process.

[0059] As Figure 7 , Figure 8 shown, in some other embodiments of the present invention, a core post extending towards the disc spring combination 5322 and reaching the inner hole of the disc spring is provided on the lower surface of the inner guide post 5323. A concave hole groove is provided on the upper surface of the inner guide post 5323, and a ball 5324 is provided in the hole groove. Each elastic device 532 contacts the device above it through the apex of the ball 5324; a spherical pressure head 5325 is installed on the bottom surface of the outer sleeve 5321, and the outer sleeve 5321 contacts the top surface of the force sensor 531 below it through the spherical surface of the spherical pressure head 5325. A top pressure bolt 5326 is threadedly connected to the middle of the top surface of the upper beam 541 of the first pulling frame 54, and the lower end surface of the top pressure bolt 5326 abuts against the ball 5324 of the uppermost elastic device 532. The beneficial effect of adopting the above technical solution is that: it ensures that the outer sleeve of the elastic device can move smoothly in the corresponding hole body of the upper beam, and prevents the outer sleeve from getting stuck when the force application occurs axial deviation.

[0060] As Figures 4 - 6 shown, in some other embodiments of the present invention, a plurality of through holes distributed in a circumferential array are provided on the top surface of the upper beam of the first pulling frame 54. Threaded holes corresponding to the through holes up and down are provided on the upper end surface of the outer sleeve 5321 of the uppermost elastic device 532. A pull rod nail 5327 is also included. The pull rod nail 5327 passes through the through hole and is connected to the threaded hole of the outer sleeve 5321. When the outer sleeve 5321 moves down to a set distance, the head of the pull rod nail 5327 abuts against the upper end surface of the through hole of the upper beam. The beneficial effect of adopting the above technical solution is that: it is convenient for the installation of the elastic device and prevents the elastic device from falling off during maintenance and debugging.

[0061] As Figure 9 ,Figure 10 As shown, in some other embodiments of the present invention, a lifting guide post 61 is provided in the upper beam 541 of the first tensioning frame 54. 2*(n - 1) lifting plates 62 are movably mounted on the lifting guide post 61 in a vertically liftable manner. Each lifting plate 62 is correspondingly provided with a lifting drive mechanism for driving its up and down movement. An opening is provided at the middle position of each lifting plate 62. From top to bottom, guide sleeves 64 are detachably and fixedly mounted at the middle openings of the 1st, 3rd,... (2n - 1)th lifting plates 62. The (n - 1)th elastic device 532 is mounted in the guide sleeve 64 on the (2n - 1)th lifting plate and can move up and down along the axis of the guide sleeve 64. From top to bottom, stop rings 65 are detachably and fixedly mounted at the middle openings of the 2nd, 4th,... (2n - 2)th lifting plates 62. A stop surface 651 is provided on the lower surface of the stop ring 65. When the force value applied by the force application mechanism 55 to the force sensor module 53 through the first tensioning frame 54 is greater than or equal to the maximum set force value of the (n - 1)th force sensor 531, the limit stop block 533 below the (n - 1)th force sensor 531 presses against the stop surface 651 of the stop ring 65 on the (2n - 2)th lifting plate. The beneficial effects of adopting the above technical solution are as follows: By using the lifting plates with adjustable height positions to carry and install the guide sleeves and stop rings, it is convenient to adjust the maximum measurement value during the range switching of each force sensor, facilitating the maximum utilization of the high-precision measurement ranges of each force sensor, thereby improving the accuracy of torque measurement. At the same time, to adapt to elastic devices and force sensors of different sizes and models, only the appropriate guide sleeves and stop rings need to be replaced, without the need to customize and process the upper beam with a specific size structure, enhancing the commonality of the first tensioning frame and reducing the manufacturing cost.

[0062] As Figure 10 shown, in some other embodiments of the present invention, a stop portion 641 extending radially inward is provided at the lower port of the central hole of the guide sleeve 64. The inner diameter of the inner edge of the stop portion 641 is smaller than the outer diameter of the outer sleeve 5321 of the corresponding elastic device, and the inner diameter of the inner edge of the stop portion 641 is larger than the outer diameter of the upper part of the force sensor 531 below it. The beneficial effects of adopting the above technical solution are as follows: It neither interferes with the upward movement of the outer sleeve when the elastic device is compressed, nor can it hold up the outer sleeve after the pressure is released, facilitating installation and debugging.

[0063] As Figure 10 shown, in some other embodiments of the present invention, an inner conical surface 652 is provided at the lower port of the central hole of the stop ring 65. An outer conical surface 5331 matching the inner conical surface of the stop ring is provided on the limit stop block 533. The beneficial effects of adopting the above technical solution are as follows: Through the guiding cooperation between the inner conical surface of the stop ring and the outer conical surface of the limit stop block, the coaxiality of each force sensor in the force sensor module is improved.

[0064] As Figure 1 , Figure 11 , Figure 12As shown in the figure, in some other embodiments of the present invention, two parallel linear guide rails 11 are respectively provided on the base 10 on both sides of the lever, and a rack 12 is provided between the two linear guide rails; a first frame 411 is slidably mounted on the linear guide rail on one side of the lever, a first balance drive mechanism 41 is fixedly mounted on the first frame 411, a first reduction motor is further provided on the first frame 411, and a gear meshing with the rack 12 is mounted on the output shaft of the first reduction motor; a second frame 421 is slidably mounted on the linear guide rail on the other side of the lever, a second balance drive mechanism 41 is fixedly mounted on the second frame 421, a second reduction motor 422 is further provided on the second frame 421, and a gear meshing with the rack 12 is mounted on the output shaft of the second reduction motor 422. The beneficial effect of adopting the above technical solution is that it is convenient to perform the axial translation of the balance drive mechanism to facilitate the installation of the device to be measured for torque.

[0065] As Figure 1 , Figure 11 , Figure 13 shown in the figure, in some other embodiments of the present invention, a first support unit 81 is further slidably mounted on the linear guide rail between the first frame 411 and the lever 30, and a second support unit 82 is further slidably mounted on the linear guide rail between the second frame 421 and the lever 30. Both the first support unit 81 and the second support unit 82 include a support base 811, a support platform 812, and a platform lifting drive mechanism 813. A third reduction motor 814 is provided on the support base 811, a gear meshing with the rack 12 is mounted on the output shaft of the third reduction motor 814, the support platform 812 is liftably mounted on the support base 811 via a vertically arranged guide post 8131, two worm gear and worm elevators 8132 arranged left and right are further mounted on the support base 811, the two worm gear and worm elevators 8132 are respectively connected to the output shaft of a double-output shaft reduction motor 8133 via couplings, the double-output shaft reduction motor 8133 drives the worm gear and worm elevators 8132 to drive the support platform 812 to move up and down, and a plurality of spaced T-shaped grooves 8121 are provided on the support platform 812. The beneficial effect of adopting the above technical solution is that the support unit can be translated along the linear guide rail and the support platform can be adjusted in height, which is convenient for the support during the measurement of devices such as torque wrenches. An auxiliary jig can be installed on the support platform to facilitate the loading and unloading of the torque device during testing.

[0066] The above embodiments are only used to illustrate the technical concept and characteristics of the present invention, and their purpose is to enable those of ordinary skill in the art to understand the content of the present invention and implement it. However, the protection scope of the present invention cannot be limited thereby. Any equivalent changes or modifications made according to the spirit and essence of the present invention should be covered within the protection scope of the present invention.

Claims

1. A torque standard machine for reducing torque measurement error, characterized in that, Comprising: Base; Lever support seat, which is installed in the middle of the base; Lever, which is installed on the lever support seat through a linear fulcrum; Balanced drive mechanism, which is located on the side of the lever and is used to keep the lever in a horizontal balanced state; Lever force application mechanism, which is used to apply a force to the end of the lever; Both ends of the device under test for torque connected to the balanced drive mechanism and the lever are connected. One end uses a rigid coupling, and the other end uses a ball tooth coupling; the rigid coupling includes a metal coupling body with an integrated structure. A through coupling hole is provided in the center of the metal coupling body. The metal coupling body is also provided with a first slit extending radially outward from the coupling hole. A circumferentially arranged dividing slit is provided in the middle of the metal coupling body, and the arc length of the dividing slit is half a circumference; the ball tooth coupling includes a first connecting shaft and a second connecting shaft. One end of the first connecting shaft is provided with a ball head, and external arc teeth are provided on the ball head. The other end of the first connecting shaft is provided with a coupling hole. One end of the second connecting shaft is provided with a hemispherical cavity, and internal arc teeth meshing with the external arc teeth are provided on the cavity wall of the cavity. The other end of the second connecting shaft is provided with a coupling hole.

2. The torque standard machine for reducing torque measurement error according to claim 1, characterized in that, The lever force application mechanism includes a blade module, a knife bearing module, a force sensor module, a first pull frame and a force application mechanism; the blade module is fixedly installed on the upper surface of the lever end. The blade module includes a blade block, and the upper part of the blade block has a convex V-shaped blade part; the knife bearing module includes a knife bearing block, and the lower surface of the knife bearing block has a concave V-shaped knife bearing groove. The knife bearing block is pressed above the blade block, and the V-shaped blade part is in linear contact with the V-shaped knife bearing groove; the force sensor module is installed above the knife bearing module. The upper beam of the first pull frame is pressed above the force sensor module. The force application mechanism applies a downward pulling force to the lower seat of the first pull frame through a connecting piece; the force sensor module includes n force sensors with different ranges, n - 1 elastic devices and n - 1 limit blocks, where n≥2. The first force sensor to the nth force sensor are distributed from top to bottom in sequence and the maximum range values increase in sequence. The nth force sensor is installed on the upper surface of the knife bearing module. One elastic device is installed above each of the first to n - 1 force sensors, and one limit block is installed below each of the first to n - 1 force sensors. Stop surfaces are provided on the upper beam of the first pull frame corresponding to the positions of each limit block. When the force value applied to the force sensor module by the force application mechanism through the first pull frame is greater than or equal to the maximum set force value of the n - 1th force sensor, the limit block below the n - 1th force sensor is pressed against the corresponding stop surface on the upper beam.

3. The torque standard machine for reducing torque measurement error according to claim 2, characterized in that, The elastic device includes an outer sleeve, a disc spring assembly, and an inner guide post. A hole body matching the outer sleeve is provided on the upper beam. The outer sleeve can move axially up and down along the corresponding hole body of the upper beam. The upper end of the outer sleeve is open. The disc spring assembly and the inner guide post are both located in the inner cavity of the outer sleeve and can move up and down. The lower end of the disc spring assembly abuts against the bottom surface of the inner cavity of the outer sleeve, and the upper end of the disc spring assembly abuts against the lower end surface of the inner guide post.

4. The torque standard machine for reducing torque measurement error according to claim 3, characterized in that, The disc spring assembly includes multiple groups of disc spring small units. The number of disc springs included in each group of disc spring small units is the same. The disc springs in the same disc spring small unit face the same direction, and the directions of adjacent disc spring small units are opposite.

5. The torque standard machine for reducing torque measurement error according to claim 2, characterized in that, A lifting guide post is provided in the upper beam of the first pulling frame. 2*(n - 1) lifting plates are installed on the lifting guide post in a liftable and movable manner. Each lifting plate is correspondingly provided with a lifting drive mechanism for driving its up and down movement. An opening is provided at the middle position of each lifting plate; from top to bottom, guide sleeves are detachably and fixedly installed at the middle openings of the 1st, 3rd... (2n - 1)th lifting plates. The (n - 1)th elastic device is installed in the guide sleeve on the (2n - 1)th lifting plate and can move axially up and down along the guide sleeve; from top to bottom, stop rings are detachably and fixedly installed at the middle openings of the 2nd, 4th... (2n - 2)th lifting plates. A stop surface is provided on the lower surface of the stop ring. When the force value applied to the force sensor module by the force application mechanism through the first pulling frame is greater than or equal to the maximum set force value of the (n - 1)th force sensor, the limit stop block below the (n - 1)th force sensor presses against the stop surface of the stop ring on the (2n - 2)th lifting plate.

6. The torque standard machine for reducing torque measurement error according to claim 1, characterized in that, A first rotary connection shaft is fixedly installed on one side surface of the lever, and a second rotary connection shaft is fixedly installed on the other side surface of the lever. The axes of the first rotary connection shaft and the second rotary connection shaft are both collinear with the linear fulcrum; the balance drive mechanism includes a first balance drive mechanism and a second balance drive mechanism. The first balance drive mechanism is located on one side of the lever, and the output shaft of the first balance drive mechanism is coaxially arranged with the first rotary connection shaft. The second balance drive mechanism is located on the other side of the lever, and the output shaft of the second balance drive mechanism is coaxially arranged with the second rotary connection shaft. The rated output torque of the second balance drive mechanism is greater than the rated output torque of the first balance drive mechanism.

7. The torque standard machine for reducing torque measurement error according to claim 6, characterized in that, Two parallel linear guide rails and a rack located between the two linear guide rails are respectively provided on the bases on both sides of the lever; a first frame is installed on the linear guide rail on one side of the lever in a translatable manner. The first balance drive mechanism is fixedly installed on the first frame. A first reduction motor is further provided on the first frame, and a gear meshing with the rack is installed on the output shaft of the first reduction motor; a second frame is installed on the linear guide rail on the other side of the lever in a translatable manner. The second balance drive mechanism is fixedly installed on the second frame. A second reduction motor is further provided on the second frame, and a gear meshing with the rack is installed on the output shaft of the second reduction motor.

8. The torque standard machine for reducing torque measurement error according to claim 7, characterized in that, A first support unit is also translatably mounted on a linear guide rail between the first frame and the lever, and a second support unit is also translatably mounted on a linear guide rail between the second frame and the lever.

9. The torque standard machine for reducing torque measurement error according to claim 8, characterized in that, Both the first support unit and the second support unit include a support base, a support platform and a platform lifting drive mechanism. A third reduction motor is provided on the support base. A gear meshing with a rack is mounted on the output shaft of the third reduction motor. The support platform is vertically and liftably mounted on the support base via guide columns. Two worm gear lifts distributed left and right are also mounted on the support base. The two worm gear lifts are respectively connected to the output shafts of a double-output shaft reduction motor via couplings. The double-output shaft reduction motor drives the worm gear lifts to drive the support platform to lift and move.

10. The torque standard machine for reducing torque measurement error according to claim 9, characterized in that, Multiple spaced T-shaped grooves are provided on the support platform.

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