A combined calibration device for electronic crane scales

Abstract

The present invention provides a combined calibration device for electronic crane scales, which relates to the technical field of calibration of measuring instruments, including a frame, a movable crossbeam, a superposition mechanism, an automatic loading and unloading mechanism for electronic crane scales and a static weight mechanism, wherein the frame has a top connecting plate, an intermediate supporting plate and a bottom plate; the superposition mechanism includes a test pressure plate, a pressure head, a standard sensor, a cylinder and a superposition pull rod; the automatic loading and unloading mechanism for electronic crane scales includes an upper pull head, an adapter, a movable seat and a cantilever bracket; the static weight mechanism includes a lower pull head, a ball head pull rod, a ball head seat, a weight connector and a weight assembly. The present invention has the following advantages: the developed combined calibration device for electronic crane scales meets the calibration of the full range and full performance of electronic crane scales, solves the major problem that large-tonnage electronic crane scales cannot be calibrated or cannot be accurately calibrated during the existing weight calibration, and the calibration device has a high degree of intelligence, high efficiency and strong safety; it is provided with an automatic loading and unloading mechanism for crane scales to achieve full-automatic installation and automatic positioning.

Description

Technical Field

[0001] The invention relates to the technical field of measuring instrument calibration, and in particular to a combined calibration device for an electronic crane scale. Background Art

[0002] An electronic crane scale is a measuring instrument that weighs the weighed object online while it is suspended. At present, there are a large number of electronic crane scales in China, which are widely used in transportation, aviation, energy, metallurgy and other industries. With the development of industry, the range of electronic crane scales is constantly expanding. The accuracy of electronic crane scales is related to trade fairness, safety protection and product quality control. In order to ensure the accuracy of its measurement performance, it needs to be regularly verified or calibrated. Therefore, the verification device and verification method play a vital role in determining the accuracy of electronic crane scales.

[0003] According to the information query, the verification or calibration of electronic crane scales is currently carried out in accordance with the National Metrology Verification Regulations JJG 539-2016, mainly in the following two forms:

[0004] First, standard weights are used for on-site calibration at the site where the crane scale is used. This method can meet the calibration requirements for small-scale (such as 500kg, 1t), but it cannot meet the calibration requirements for large-scale electronic crane scales, such as 30 / 50 / 80 / 100 tons. The main problems are as follows: 1. There is not enough space to hang the standard weights during calibration; 2. The carrying capacity of the hoisting device at the calibration site is limited; 3. The safety of the calibration site is poor and the work efficiency is low; 4. The transportation volume of weights is large and the cost is high; 5. It is impossible to achieve full-scale and full-performance calibration of electronic crane scales.

[0005] The second is to use force standard devices for calibration. The existing superposition type or static weight type force standard devices for calibration have the following problems: 1. Large-scale electronic crane scales are difficult to install and have poor safety. According to survey data, the large-scale crane scales currently produced by manufacturers are large in size and heavy in weight. The weight of a 100-ton electronic crane scale produced by some manufacturers is about 1 ton. Therefore, it is difficult for calibration personnel to send the crane scale to the designated location by manual or mechanical means, and there are safety hazards during installation; 2. Whether it is a superposition type or a static weight type force standard device, there is insufficient test space when calibrating a large-scale electronic crane scale, which cannot meet the requirements of the test space of a large-scale electronic crane scale; 3. When using a superposition type standard machine for calibration, it is impossible to perform calibration according to the regulations. According to the requirements for calibrating electronic crane scales in JJG 539-2016 "Digital Indicating Scales", due to its limited force value control range, the existing superposition type force standard machine cannot achieve the calibration requirements of the minimum weighing of the electronic crane scale of 10e and 20e (e is the calibration division value). 4. The static gravity force standard machine is used for calibration, but the calibration efficiency is low and cannot meet the calibration requirements of the lower limit of the range and the identification threshold. At the same time, the static gravity force standard machine is expensive, especially when the range is large, its cost is particularly high. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a combined calibration device for electronic crane scales. By combining the advantages of the superposition force standard device principle and the static weight force standard principle, a combined standard device with a superposition structure and a static weight loading mechanism is designed to achieve full-range and full-performance calibration of the electronic crane scale according to regulations.

[0007] The present invention is implemented as follows: a combined calibration device for an electronic crane scale, comprising a frame, a movable crossbeam, a stacking mechanism, an automatic loading and unloading mechanism for the electronic crane scale and a static weight mechanism, wherein the frame has a top connecting plate, an intermediate supporting plate and a bottom plate, and the movable crossbeam is slidably connected to the frame up and down and is located between the top connecting plate and the intermediate supporting plate;

[0008] The stacking mechanism comprises a test platen, a pressure head, a standard sensor, an oil cylinder and a stacking rod, the cylinder body of the oil cylinder is fixedly connected to the moving crossbeam, a base plate is fixedly arranged on the piston of the oil cylinder, the base plate is located above the moving crossbeam, the base plate is fixedly arranged with the standard sensor, the pressure head is fixedly connected to the test platen, the pressure head abuts against the standard sensor, the stacking rod passes through the center holes of the oil cylinder and the base plate and is slidably connected, and one end of the stacking rod is fixedly connected to the test platen;

[0009] The automatic loading and unloading mechanism of the electronic crane scale includes an upper pull head, an adapter, a movable seat and a cantilever bracket, the cantilever bracket is fixedly connected to the movable crossbeam, the movable seat is slidably connected to the cantilever bracket, the movable seat is located below the movable crossbeam, the adapter has a convex portion, the adapter is slidably connected to the movable seat up and down, the convex portion can clamp the movable seat, the adapter is also fixedly connected to the upper pull head, the adapter is provided with a groove, and the other end of the superimposed pull rod is matched and connected to the groove;

[0010] The static weight mechanism includes a pull-down head, a ball head pull rod, a ball head seat, a weight connector and a weight assembly, the pull-down head is located above the intermediate support plate, the intermediate support plate is fixedly provided with the ball head seat, the ball head pull rod passes through the ball head seat and is slidably connected, one end of the ball head pull rod is fixedly connected to the pull-down head, the other end of the ball head pull rod is fixedly connected to one end of the weight connector, and the other end of the weight connector is detachably connected to the weight assembly.

[0011] Furthermore, it also includes a beam driving mechanism, which includes a first screw rod and a first servo motor, the top end of the first screw rod is rotatably connected to the top connecting plate, the bottom end of the first screw rod is rotatably connected to the intermediate support plate, the first screw rod is also threadedly connected to the movable beam, the body of the first servo motor is fixedly connected to the top connecting plate, and the output shaft of the first servo motor is transmission-connected to the top end of the first screw rod.

[0012] Furthermore, the beam driving mechanism also includes a guide column, which is fixed between the top connecting plate and the middle supporting plate, and the movable beam is slidably connected to the guide column.

[0013] Furthermore, the superposition mechanism also includes a force equalizing plate, there are a plurality of standard sensors and they are fixedly arranged along the circumferential direction of the substrate, the number of the pressure heads corresponds to the number of the standard sensors, and each of the pressure heads is fixedly connected to the force equalizing plate.

[0014] Furthermore, the automatic loading and unloading mechanism of the electronic crane scale also includes a second screw rod, a second servo motor and a bearing seat. There are two bearing seats and they are respectively fixed at the two ends of the cantilever bracket. The two ends of the second screw rod are respectively rotatably connected to the bearing seats. The second screw rod passes through the movable seat and is threadedly connected. The body of the second servo motor is fixedly connected to one of the bearing seats, and the output shaft of the second servo motor is transmission connected to the second screw rod.

[0015] Furthermore, the automatic loading and unloading mechanism of the electronic crane scale also includes a first linear guide and a first linear slider, the first linear guide is fixedly connected to the cantilever bracket, the first linear slider is fixedly connected to the moving seat, and the first linear slider is slidably connected to the first linear guide.

[0016] Furthermore, it also includes a weight lifting drive mechanism, which includes a weight lifting plate, a third screw rod and a third servo motor, the top end of the third screw rod is rotatably connected to the intermediate support plate, the bottom end of the third screw rod is rotatably connected to the bottom plate, the third screw rod is also threadedly connected to the weight lifting plate, the body of the third servo motor is fixedly connected to the bottom plate, and the output shaft of the third servo motor is drivingly connected to the bottom end of the third screw rod;

[0017] The weight assembly includes a weight connecting seat, a weight connecting sleeve, a weight connecting shaft, and a weight body with an inner hole. There are multiple weight bodies. The weight body at the top is fixedly connected to the weight connecting seat. The weight connecting seat is clamped on the lower end of the weight connecting piece. The weight connecting shaft and the weight connecting sleeve are arranged between the upper and lower adjacent weight bodies. The upper end of the weight connecting shaft is embedded in the inner hole of the upper weight body. The lower end of the weight connecting shaft is fixedly connected to the weight connecting sleeve by a thread. The weight connecting sleeve is also fixedly connected to the inner hole of the weight body below. The weight body at the bottom is placed on the upper surface of the weight lifting plate.

[0018] Furthermore, it also includes a weight conveying mechanism, which includes a weight moving plate, a second linear guide, a second linear slider and a guide support column, the second linear guide is fixedly connected to the upper surface of the weight lifting plate, the second linear guide is also fixedly connected to the guide support column, the second linear slider is fixedly connected to the lower surface of the weight moving plate, the second linear slider is slidably connected to the second linear guide, and the weight body at the bottom is placed on the upper surface of the weight moving plate.

[0019] Furthermore, the weight conveying mechanism also includes a weight positioning seat, the bottom end of the weight positioning seat is fixedly connected to the weight moving plate, and the top end of the weight positioning seat can be inserted into the inner hole of the weight body at the bottom.

[0020] Furthermore, it also includes an identification threshold testing mechanism, which includes a guide frame, a fourth screw rod, a test moving beam and a force sensor, the guide frame is fixedly connected to the lower surface of the intermediate support plate, the test moving beam is slidably connected to the guide frame up and down, both ends of the fourth screw rod are rotatably connected to the guide frame, the fourth screw rod is also threadedly connected to the test moving beam, the force sensor is fixedly connected to the test moving beam, the weight connecting piece passes through the force sensor and is slidably connected, and the weight connecting piece has a retaining ring, and the retaining ring is located below the force sensor.

[0021] The invention has the following advantages: 1. The developed combined calibration device for electronic crane scales can realize the full-range and full-performance calibration of electronic crane scales in accordance with the regulation JJG 539-2016 "Digital Indicating Scales" in a true sense, solving the major problem that the existing large-range electronic crane scales cannot be calibrated or cannot be accurately calibrated with weights. The calibration device has high intelligence, high efficiency and strong safety;

[0022] 2. This device combines the dual advantages of superposition structure and static weight structure, that is, the superposition structure has the advantages of fast loading speed, good stability, high upper limit of measuring range and low cost, while the static weight structure has high accuracy, stable force loading and unloading, and can solve the problem that the lower limit of the measuring range of electronic crane scale cannot be detected.

[0023] 3. The device is equipped with an automatic loading and unloading mechanism for the crane scale, which can solve the problems of poor safety and high work intensity during manual installation of the crane scale, and realize full-automatic installation and automatic positioning;

[0024] 4. The device is equipped with a discrimination threshold test mechanism, which can meet the requirements of the discrimination threshold test and solve the problems of heavy workload and high error rate when adding small weights manually. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention will be further described below in conjunction with embodiments with reference to the accompanying drawings.

[0026] Figure 1 It is a schematic structural stereogram of the combined calibration device of the electronic crane scale of the present invention.

[0027] Figure 2 It is a schematic plan view of the structure of the combined calibration device of the electronic crane scale of the present invention.

[0028] Figure 3 for Figure 2 A is a partial enlarged schematic diagram of the middle part.

[0029] Figure 4 It is a three-dimensional diagram showing the positional relationship among the movable crossbeam, the stacking mechanism and the automatic loading and unloading mechanism of the electronic crane scale in the present invention.

[0030] Figure 5 It is a schematic diagram of assembling the stacked pull rod, the movable seat and the adapter in the present invention.

[0031] Figure 6 It is a schematic front view of the structure of the automatic loading and unloading mechanism of the electronic crane scale in the present invention.

[0032] Figure 6a for Figure 6 Right view of .

[0033] Figure 6b for Figure 6 Top view of the .

[0034] Figure 7 It is a schematic plan view of the assembly of the movable crossbeam, the stacking mechanism and the automatic loading and unloading mechanism of the electronic crane scale in the present invention.

[0035] Figure 7a for Figure 7 BB section diagram.

[0036] Figure 8 It is a schematic diagram of the assembly of the oil cylinder, standard sensor, pressure head and force equalizing plate in the present invention.

[0037] Fig. 9 Schematic diagram of the loading state of the weight assembly in the present invention.

[0038] Figure 9a for Fig. 9 Schematic diagram of CC section view.

[0039] Fig.10 It is a schematic diagram of the unloading state of the weight assembly in the present invention.

[0040] Fig.10a for Fig.10 DD section diagram.

[0041] Fig.11 It is a schematic diagram of the assembly of the lower pull head, the ball head pull rod, the middle support plate and the weight connector in the present invention.

[0042] Fig.12 It is a schematic structural stereogram of the weight conveying mechanism in the present invention.

[0043] Fig.13 It is a schematic plan view of the structure of the weight conveying mechanism in the present invention.

[0044] Markings in the figure: frame 1, top connecting plate 11, middle supporting plate 12, bottom plate 13, upper column 14, lower column 15, moving crossbeam 2, superposition mechanism 3, test pressure plate 31, pressure head 32, standard sensor 33, cylinder 34, piston 341, superposition pull rod 35, base plate 36, force equalizing plate 37, automatic loading and unloading mechanism 4 of electronic crane scale, upper pull head 41, adapter 42, convex part 421, groove 422, moving seat 43, cantilever bracket 44, second screw rod 45, second servo motor 46, bearing seat 47, first linear guide rail 48, first linear slide block 49, static weight mechanism 5, lower pull head 51, ball head pull rod 52, ball head seat 53, weight connector 54, retaining ring 541 , weight assembly 55, weight connecting seat 551, weight connecting sleeve 552, weight connecting shaft 553, weight body 554, inner hole 5541, beam driving mechanism 6, first screw rod 61, first servo motor 62, plum blossom coupling 63, commutator 64, reducer 65, guide column 66, weight lifting driving mechanism 7, weight lifting plate 71, third screw rod 72, third servo motor 73, weight conveying mechanism 8, weight moving plate 81, handle 811, second linear guide rail 82, second linear slider 83, guide rail support 84, weight positioning seat 85, identification threshold testing mechanism 9, guide frame 91, guide rod 911, fourth screw rod 92, test moving beam 93, force sensor 94. DETAILED DESCRIPTION

[0045] See also Figures 1 to 13, a preferred embodiment of the combined calibration device of the electronic crane scale of the present invention; includes a frame 1, a moving beam 2, a superposition mechanism 3, an automatic loading and unloading mechanism 4 for the electronic crane scale and a static weight mechanism 5, and also includes a beam driving mechanism 6, a weight lifting driving mechanism 7, a weight conveying mechanism 8 and a discrimination threshold testing mechanism 9; the frame 1 has a top connecting plate 11, an intermediate support plate 12 and a bottom plate 13, the moving beam 2 is slidably connected to the frame 1 up and down, and is located between the top connecting plate 11 and the intermediate support plate 12; the frame 1 also has a plurality of upper columns 14 and a lower column 15, the two ends of the upper column 14 are respectively connected to the top connecting plate 11 and the intermediate support plate 12 by nuts, and the two ends of the lower column 15 are respectively connected to the intermediate support plate 12 and the bottom plate 13 by nuts.

[0046] The beam driving mechanism 6 includes a first screw rod 61 and a first servo motor 62. The top end of the first screw rod 61 is rotatably connected to the top connecting plate 11, and the bottom end of the first screw rod 61 is rotatably connected to the intermediate supporting plate 12. Both ends of the first screw rod 61 cooperate with the provided bearings to rotate; the first screw rod 61 is also threadedly connected to the movable beam 2, so that when the first screw rod 61 rotates forward or reversely, the movable beam 2 can move up and down; the body of the first servo motor 62 is fixedly connected to the top connecting plate 11, and the output shaft of the first servo motor 62 is transmission-connected to the top end of the first screw rod 61. More specifically, the beam drive mechanism 6 also includes a plum blossom coupling 63, a commutator 64 and a reducer 65. The output shaft of the first servo motor 62 is connected to the commutator 64 through the plum blossom coupling 63. The commutator 64 converts the rotation direction required for the output according to the rotation direction of the first servo motor 62, thereby driving the reducer 65 connected to the commutator 64. The reducer 65 converts the rotation speed of the first servo motor 62 into the required specific rotation speed through a certain reduction ratio, thereby driving the first screw rod 61 connected thereto, and then causing the screw rod to rotate. The beam drive mechanism 6 also includes a guide column 66, which is fixed between the top connecting plate 11 and the middle supporting plate 12, and the movable beam 2 is slidably connected to the guide column 66. The guide column 66 makes the movable beam 2 slide up and down stably. Please refer to the position of the guide column 66 and the first screw rod 61. Figure 1 and Figure 2 .

[0047] Please refer to Figure 4 , Figure 5 , Figures 7 and 8The superposition mechanism 3 includes a test platen 31, a pressure head 32, a standard sensor 33, a cylinder 34 and a superposition rod 35. The cylinder body of the cylinder 34 is fixedly connected to the moving beam 2. A base plate 36 is fixedly provided on the piston 341 of the cylinder 34. The base plate 36 is located above the moving beam 2. The standard sensor 33 is fixedly provided on the base plate 36. The pressure head 32 is fixedly connected to the test platen 31. The pressure head 32 abuts against the standard sensor 33. The superposition rod 35 passes through the center holes of the cylinder 34 and the base plate 36 and is slidably connected. One end of the superposition rod 35 is fixedly connected to the test platen 31. The superposition mechanism 3 is a device for providing a superposition force source during the calibration of the electronic crane scale. During the calibration work, the piston 341 of the oil cylinder 34 moves upward, thereby driving the standard sensor 33, the pressure head 32 and the test pressure plate 31 on the base plate 36 to move upward. At this time, the standard sensor 33 applies an upward force to the pressure head 32. The pressure head 32 and the standard sensor 33 are positioned through the center hole. The other end of the stacked pull rod 35 pulls the adapter 42 upward. The upper pull head 41 connected to the adapter 42 is installed with an electronic crane scale. The standard sensor 33 can detect the force value applied by the oil cylinder 34, and the electronic crane scale also displays the force value. The electronic crane scale is calibrated by comparing these two force values.

[0048] The superposition mechanism 3 further includes a force equalizing plate 37, the standard sensors 33 are in plurality and fixedly arranged along the circumferential direction of the base plate 36, the number of the pressure heads 32 corresponds to the number of the standard sensors 33, and each of the pressure heads 32 is fixedly connected to the force equalizing plate 37. In this way, the force applied by the oil cylinder 34 is more evenly transmitted to each pressure head 32 and the test pressure plate 31, and the electronic crane scale is more accurately calibrated in combination with the force values ​​measured by each standard sensor 33.

[0049] Please refer to Figures 6 to 7aThe automatic loading and unloading mechanism 4 of the electronic crane scale includes an upper puller 41, an adapter 42, a moving seat 43 and a cantilever bracket 44, and also includes a second screw 45, a second servo motor 46 and a bearing seat 47 and a first linear guide 48 and a first linear slider 49; the cantilever bracket 44 is fixedly connected to the moving crossbeam 2, the first linear guide 48 is fixedly connected to the cantilever bracket 44, the first linear slider 49 is fixedly connected to the moving seat 43, and the first linear slider 49 is slidably connected to the first linear guide 48; the moving seat 43 is located below the moving crossbeam 2, the adapter 42 has a convex portion 421, the adapter 42 and the moving seat 43 The up and down sliding connection, the protrusion 421 can clamp the movable seat 43, the adapter 42 is also fixedly connected to the upper pull head 41, the adapter 42 is provided with a groove 422, the other end of the stacking pull rod 35 is matched and connected with the groove 422; specifically, the groove 422 is an inverted "T" groove 422, the other end of the stacking pull rod 35 is clamped into the inverted "T" groove 422, when the stacking pull rod 35 moves upward, the adapter 42 can be lifted, thereby applying an upward force to the electronic crane scale installed on the upper pull head 41 connected to the adapter 42; when the stacking pull rod 35 is not working, the protrusion 421 of the adapter 42 clamps the movable seat 43 to prevent the adapter 42 from detaching from the movable seat 43. There are two bearing seats 47 and they are fixed at the two ends of the cantilever bracket 44 respectively. The two ends of the second screw rod 45 are rotatably connected to the bearing seats 47 respectively. The second screw rod 45 passes through the moving seat 43 and is threadedly connected. The body of the second servo motor 46 is fixedly connected to one of the bearing seats 47, and the output shaft of the second servo motor 46 is transmission-connected to the second screw rod 45. The second servo motor 46 causes the second screw rod 45 to rotate forward or reverse, thereby moving the moving seat 43 forward and backward; when the electronic crane scale to be calibrated needs to be replaced, the moving seat 43 moves outward under the drive of the second servo motor 46, and the inverted "T"-shaped groove 422 of the adapter 42 is disengaged from the other end of the superimposed pull rod 35. When the moving seat 43 moves outward to the specified position, the staff replaces the electronic crane scale located at the upper pull head 41, and the upper end of the electronic crane scale is fixed to the upper pull head 41 by a latch.

[0050] The automatic loading and unloading mechanism 4 of the electronic crane scale is used to install and disassemble the inspected electronic crane scale; when the electronic crane scale needs to be installed, the first servo drives the first screw 61 to rotate, driving the moving beam 2 to move downward to the required position, and the second servo motor 46 drives the second screw 45 to rotate. The second screw 45 drives the moving seat 43 and the first linear slider 49 to move outward on the first linear guide 48 through the ball screw nut. The adapter 42 and the upper pull head 41 move outward together with the moving seat 43, and stop when they move to the position where the hook of the electronic crane scale can be buckled. After the upper hook part of the electronic crane scale is fixed to the upper pull head 41 by the latch, the moving beam 2 moves upward, and when the lower hook part of the electronic crane scale can cooperate with the lower pull head 51, the movement of the moving beam 2 is stopped; at the same time, the second servo motor 46 will drive the second screw 45 to drive the moving seat 43 and the upper pull head 41 and the electronic crane scale of the upper pull head 41 to move to the center of the frame 1. A positioning device is provided at the center of the frame 1. When the moving seat 43 moves to the positioning device, the movement stops. At this time, the upper pull head 41 is in the center of the frame 1. At this time, the up and down movement of the moving beam 2 is fine-tuned to make the lower hook part of the electronic crane scale fully cooperate and contact with the lower pull head 51, and the latch is inserted. At this time, the installation of the electronic crane scale is completed. After the electronic crane scale is calibrated, it is necessary to remove the electronic crane scale from the frame 1. The operation scheme is the opposite of that during loading.

[0051] Please refer to Figures 9 to 11 The static weight mechanism 5 includes a lower pull head 51, a ball head pull rod 52, a ball head seat 53, a weight connector 54 and a weight assembly 55. The lower pull head 51 is located above the intermediate support plate 12, and the intermediate support plate 12 is fixedly provided with the ball head seat 53. The ball head pull rod 52 passes through the ball head seat 53 and is slidably connected. One end of the ball head pull rod 52 is fixedly connected to the lower pull head 51, and the other end of the ball head pull rod 52 is fixedly connected to one end of the weight connector 54. The other end of the weight connector 54 is detachably connected to the weight assembly 55. When performing calibration, the required weight is added to the other end of the weight connector 54, and the weight connector 54 has an added downward force, so that the ball head pull rod 52 and the lower pull head 51 have this downward force. The lower pull head 51 is equipped with an electronic crane scale, and the electronic crane scale displays the force value. The staff calculates the weight marked with the added weight and compares it, so that the electronic crane scale is calibrated statically.

[0052] The weight lifting drive mechanism 7 includes a weight lifting plate 71, a third screw rod 72 and a third servo motor 73. The top end of the third screw rod 72 is rotatably connected to the intermediate support plate 12, and the bottom end of the third screw rod 72 is rotatably connected to the bottom plate 13. The third screw rod 72 is also threadedly connected to the weight lifting plate 71. When the third screw rod 72 rotates forward or reversely, the weight lifting plate 71 is lifted and moved; the body of the third servo motor 73 is fixedly connected to the bottom plate 13, and the output shaft of the third servo motor 73 is transmission-connected to the bottom end of the third screw rod 72; referring to the above paragraph, a plum blossom coupling, a commutator and a reducer are also arranged between the third servo motor 73 and the third screw rod 72.

[0053] See also Figures 9 to 10a The weight assembly 55 includes a weight connection seat 551, a weight connection sleeve 552, a weight connection shaft 553, and a weight body 554 with an inner hole 5541. The weight body 554 has a plurality of weight bodies. The weight body 554 at the top is fixedly connected to the weight connection seat 551. The weight connection seat 551 is clamped at the lower end of the weight connector 54. The weight connection shaft 553 and the weight body 554 are arranged between the upper and lower adjacent weight bodies 554. The weight connecting sleeve 552 is provided, the upper end of the weight connecting shaft 553 is embedded in the inner hole 5541 of the upper weight, the lower end of the weight connecting shaft 553 is fixedly connected to the weight connecting sleeve 552 by a thread, and the weight connecting sleeve 552 is also fixedly connected to the inner hole 5541 of the lower weight; the weight body 554 at the bottom is placed on the upper surface of the weight moving plate 81, and the weight moving plate 81 is placed on the weight lifting plate 71. According to actual conditions, the weight body 554 has a variety of weight specifications, and there are a plurality of weight bodies 554 of each weight specification.

[0054] The weights are connected by step-by-step socketing. The weight assembly 55 is specifically assembled as follows: the weight connection sleeve 552 is fixedly installed on the inner hole 5541 of the nth weight body 554 at the bottom by a plurality of bolts, and then the n-1th weight body 554 is placed, and the weight connection shaft 553 is passed through the inner hole 5541 of the n-1th weight body and is installed with the weight connection sleeve 552 by threaded connection. After installation, the weight connection sleeve 552 on the n-1th weight body 554 is installed, and so on, the weight bodies 554 are installed from bottom to top until the first weight body 554 at the top is installed, and finally the weight connection seat 551 and the weight connector 54 are installed. When loading, as shown in the figure, the weight lifting mechanism drives the weight lifting plate 71 to move downward, and the weight lifting plate 71 drives the weight as a whole to move downward until the weight connecting member 54 contacts the weight connecting seat 551. At this time, the weight connecting member 54 pulls up the weight connecting seat 551 and its first weight body 554 together, thereby realizing the loading of the first weight body 554. When it is necessary to load the second weight body 554, continue to send instructions to the weight lifting drive mechanism 7, so that the weight lifting drive mechanism 7 continues to drive the weight lifting plate 71 to move downward until the upper end of the weight connecting shaft 553 connected to the second weight body 554 contacts the inner hole 5541 of the weight body 554, thereby realizing the loading of the second weight, and so on, until all weight bodies 554 are loaded. When unloading, the weight lifting drive mechanism 7 drives the weight lifting plate 71 to move upward until the upper surface of the nth weight body 554 at the bottom is in contact with the lower surface of the n-1th weight body 554. At this time, the upper end of the weight connecting shaft 553 is separated from the n-1th weight body 554, and the unloading of the nth weight body 554 is achieved. Similarly, the weight lifting plate 71 continues to move upward until the weight connecting seat 551 of the first weight body 554 at the top is separated from the lower end of the weight connecting member 54, and the unloading of all weights is completed.

[0055] Please refer to Figure 12 to Figure 13The weight conveying mechanism 8 includes a weight moving plate 81, a second linear guide 82, a second linear slider 83 and a guide support column. The second linear guide 82 is fixedly connected to the upper surface of the weight lifting plate 71. The second linear guide 82 is also fixedly connected to the guide support column. The second linear slider 83 is fixedly connected to the lower surface of the weight moving plate 81. The second linear slider 83 is slidably connected to the second linear guide 82. The weight body 554 at the bottom is placed on the upper surface of the weight moving plate 81. When the weight assembly 55 needs to be removed, the connection between the weight connecting seat 551 and the top weight body 554 is removed, the weight lifting plate 71 is moved downward to its original position, and then the weight moving plate 81 is moved from the position of the weight lifting plate 71 to the position of the guide support column. A handle 811 is fixedly provided on the weight moving plate 81 to facilitate the staff to move the weight moving plate 81. The weight conveying mechanism 8 further comprises a weight positioning seat 85, the bottom end of which is fixedly connected to the weight moving plate 81, and the top end of which can be inserted into the inner hole 5541 of the weight body 554 at the bottom; the weight positioning seat 85 is conical.

[0056] Please refer to Figure 3 and Fig.11 The identification threshold test mechanism 9 includes a guide frame 91, a fourth screw rod 92, a test moving beam 93 and a force sensor 94. The guide frame 91 is fixedly connected to the lower surface of the intermediate support plate 12. The test moving beam 93 is slidably connected to the guide frame 91, wherein the guide frame 91 has a guide rod 911, and the test moving beam 93 is slidably connected to the guide rod 911; both ends of the fourth screw rod 92 are rotatably connected to the guide frame 91, and the fourth screw rod 92 is also threadedly connected to the test moving beam 93. When the fourth screw rod 92 rotates forward or reversely, the test moving beam 93 can move up and down; the force sensor 94 is fixedly connected to the test moving beam 93, and the weight connecting member 54 passes through the force sensor 94 and is slidably connected. The weight connecting member 54 has a retaining ring 541, and the retaining ring 541 is located below the force sensor 94. The force sensor 94 can adopt a small range to meet the loading requirements in the identification threshold detailed table. When performing the electronic crane scale identification threshold test, the test moving beam 93 moves downward, so that the force sensor 94 generates a downward force on the retaining ring 541, and the force sensor 94 displays the value of the force. The downward force is applied to the weight connecting member 54, and then applied to the ball head pull rod 52, the lower pull head 51 and the electronic crane scale. According to actual needs, the movement of the test moving beam 93 is adjusted to control the magnitude of the force applied to the weight connecting member 54, and the force sensor 94 displays the change in the applied force value. At the same time, the staff observes whether the displayed value of the electronic crane scale changes and the amount of change.

[0057] The function of the identification threshold test mechanism 9 is to be the loading structure required for the identification threshold test during the verification of the electronic crane scale. According to the requirements of the National Metrology Verification Regulations JJG 539-2016 "Digital Indicating Scale", when the electronic crane scale is verified, its identification threshold needs to be tested, and the test process is carried out in the following manner: "On the scale in a balanced state, gently put or remove an additional load equal to 1.4 times (1.4e) of the actual division value, and the scale indication should change significantly at this time." According to the requirements of the regulations, the current verification of the identification threshold of the electronic crane scale is mainly carried out by manual loading, usually loading every 0.1e, that is, preparing small weights of different weights according to different division values. As shown in Table 1 below, the corresponding division values ​​of electronic crane scales of different specifications are different, and a large number of small weights of different specifications need to be prepared. When loading is required, the electronic crane scale is loaded manually one by one (0.1e) until the small weights of 1.4e are added. This loading method has a low degree of automation, a large workload, and low efficiency. Manual loading is also prone to high error rates. Therefore, the discrimination threshold test mechanism 9 provided in the present invention can realize automatic loading and unloading of the discrimination threshold test with high accuracy and high automation level.

[0058] During loading: When the electronic crane scale is in a balanced state (i.e., the weight is in a loaded state), the fourth servo motor drives the fourth screw rod 92 to rotate, so that the test moving beam 93 moves downward along the guide rod 911. When the force sensor 94 on the test moving beam 93 contacts the retaining ring 541 of the weight connector 54, a force value is generated. According to the principle of action and reaction force, a load is applied to the weight connector 54, i.e., a load is applied to the electronic crane scale. At this time, the rotation amount of the fourth servo motor is controlled by the control system, and a load increase of 0.1e is slowly applied to the force sensor 94 until the loading of 1.4e is completed. At this time, observe whether the indication of the electronic crane scale has changed significantly, i.e., the test of the identification threshold is completed.

[0059] Table 1. Discrimination threshold loading details

[0060]

[0061] Specific implementation scheme of the combined calibration device of the electronic crane scale of the present invention: Taking the combined calibration device of the present invention with a range of 50t to calibrate a 30-ton electronic crane scale as an example, the calibration device contains 5000kg weights, and the weights are as follows from top to bottom: 10kg, 10kg, 20kg, 10kg, 50kg, 100kg, 200kg, 100kg, 500kg, 500kg, 500kg, 500kg, 1000kg, 1000kg g, the total weight is 5000kg, so the electronic crane scale uses weights for calibration in the small range of 200-5000kg, and uses a superposition structure for calibration in the large range of (5000-30000)kg. The graduation value e of the electronic crane scale is 10kg, and the calibration points are 20e, 500e, 50%max, 2000e, max, that is, the calibration points are 200kg, 5000kg, 15000kg, 20000kg, and 30000kg.

[0062] When the electronic crane scale needs to be calibrated, the electronic crane scale is placed on the middle support plate 12, and the automatic loading and unloading mechanism 4 of the electronic crane scale is driven by the second servo motor 46 to move the upper pull head 41 along the first linear guide rail 48 to the specified position, and the beam driving mechanism 6 drives the moving beam 2 to move downward until the upper pull head 41 reaches the upper hook position of the electronic crane scale. At this time, the upper hook of the electronic crane scale is placed inside the upper pull head 41 and the latch is inserted; then the upper pull head 41 is driven by the second servo motor 46 to be sent to a place where it can cooperate with the superimposed pull rod 35, and then the other end of the superimposed pull rod 35 enters the inverted "T" groove 422 of the adapter 42. After reaching the specified position, the moving beam 2 rises until the lower pull hook of the electronic crane scale can be connected with the lower pull head 51 of the present invention. At this time, the latch is inserted into the lower pull head 51, and the installation of the electronic crane scale is completed. When the electronic crane scale needs to be disassembled, the operation process is opposite to that of the installation process. After the installation of the electronic crane scale is completed, the calibration is started.

[0063] During calibration, weights are used for loading within the range of 5000kg. The first servo motor 62 synchronously drives the four first screws 61 through the coupling 63, the commutator 64 and the reducer 65. The first screw 61 drives the moving beam 2 to move upward until the electronic crane scale under test produces an indication value, and the displacement sensor installed on the middle connecting plate starts to output a displacement signal. When the displacement signal reaches the target value, the hanging part is combined with the lower hook of the electronic crane scale and separated from the first-level weight, and the moving beam 2 stops, completing the load of the lower pull head 51 and the weight connector 54 under the gravity of the hanging part, and the electronic crane scale is reset at this time.

[0064] Next, the weight lifting drive mechanism 7 starts to work, and the third servo motor 73 drives the four third screws 72 to rotate synchronously through the coupling, the steering gear and the reducer, driving the weight lifting plate 71 to move downward, and uses the displacement signal of the weight lifting plate 71 to perform a servo closed-loop control system. When the target weight is not loaded, the displacement signal is used to control the weight lifting plate 71 to move until the sixth weight (100kg) is loaded in place, that is, the first calibration point of 200kg is loaded. At this time, the reading of the electronic crane scale is the reading of the first calibration point. The second calibration point is 5000kg, and the third servo motor 73 continues to control the weight lifting plate 71 to move downward until all weights are loaded, that is, the displacement sensor information reaches the target setting value. At this time, the weight is separated from the weight moving plate 81, the loading of the 5000kg weight is completed, and the reading of the electronic crane scale is read.

[0065] After the weight loading is completed, the large-scale calibration is carried out using a superposition structure. Because the oil cylinder 34 and the standard sensor 33 are installed on the moving crossbeam 2, the compressive force of the standard sensor 33 can be converted into a tensile force through the reaction structure composed of the superimposed pull rod 35 and the upper pull head 41. When the superposition system is working, the servo hydraulic power system controls the loading cylinder 34, and the standard sensor 33 and the electronic crane scale under test are loaded simultaneously through the action force between the upper pull head 41 and the superimposed pull rod 35. The force value of the standard sensor 33 is used as the reference force standard to form a closed-loop control system. The electronic crane scale under test is connected in series with the standard sensor 33 group through the upper pull head 41, and the force magnitude is equal. When the standard sensor 33 reaches the target setting value, the loading of the calibration point is completed.

[0066] The identification threshold test is performed at 20e, 50%max, and max, i.e., 200kg, 15000kg, and 30000kg. Taking the loading of 20e as an example, when the weight is loaded with 20e (200kg), the identification threshold test system is started, and the fourth servo motor in the identification threshold test mechanism 9 drives the fourth screw 92 to drive the test moving beam 93 and the force sensor 94 to move downward until the force sensor 94 contacts the retaining ring 541 of the weight connector 54, thereby generating an indication. A closed-loop control system is formed by the force sensor 94 and the fourth servo motor, and a force value of 0.1e (1kg) is slowly loaded until the force sensor 94 completes a force value of 1.4e (14kg). At this time, observe whether the indication of the electronic crane scale changes significantly, and record the change results. After the test is completed, the fourth servo motor drives the test moving beam 93 to move upward, and the test moving beam 93 and the force sensor 94 are separated from the weight connector 54, thereby completing the identification threshold test.

[0067] Although the specific implementation modes of the present invention are described above, those skilled in the art should understand that the specific implementation modes described are only illustrative and are not intended to limit the scope of the present invention. Equivalent modifications and changes made by those skilled in the art in accordance with the spirit of the present invention should be included in the scope of protection of the claims of the present invention.

Claims

1. A combined calibration device for an electronic crane scale, characterized in that: It includes a frame, a moving crossbeam, a stacking mechanism, an automatic loading and unloading mechanism for an electronic crane scale, and a static weight mechanism. The frame has a top connecting plate, an intermediate supporting plate, and a bottom plate. The moving crossbeam is slidably connected to the frame up and down and is located between the top connecting plate and the intermediate supporting plate. The stacking mechanism comprises a test platen, a pressure head, a standard sensor, an oil cylinder and a stacking rod, the cylinder body of the oil cylinder is fixedly connected to the moving crossbeam, a base plate is fixedly arranged on the piston of the oil cylinder, the base plate is located above the moving crossbeam, the base plate is fixedly arranged with the standard sensor, the pressure head is fixedly connected to the test platen, the pressure head abuts against the standard sensor, the stacking rod passes through the center holes of the oil cylinder and the base plate and is slidably connected, and one end of the stacking rod is fixedly connected to the test platen; The automatic loading and unloading mechanism of the electronic crane scale includes an upper pull head, an adapter, a movable seat and a cantilever bracket, the cantilever bracket is fixedly connected to the movable crossbeam, the movable seat is slidably connected to the cantilever bracket, the movable seat is located below the movable crossbeam, the adapter has a convex portion, the adapter is slidably connected to the movable seat up and down, the convex portion can clamp the movable seat, the adapter is also fixedly connected to the upper pull head, the adapter is provided with a groove, and the other end of the superimposed pull rod is matched and connected to the groove; The static weight mechanism includes a pull-down head, a ball head pull rod, a ball head seat, a weight connector and a weight assembly, the pull-down head is located above the intermediate support plate, the intermediate support plate is fixedly provided with the ball head seat, the ball head pull rod passes through the ball head seat and is slidably connected, one end of the ball head pull rod is fixedly connected to the pull-down head, the other end of the ball head pull rod is fixedly connected to one end of the weight connector, and the other end of the weight connector is detachably connected to the weight assembly.

2. The combined calibration device for an electronic crane scale according to claim 1, characterized in that: It also includes a beam driving mechanism, which includes a first screw rod and a first servo motor. The top end of the first screw rod is rotatably connected to the top connecting plate, the bottom end of the first screw rod is rotatably connected to the intermediate support plate, the first screw rod is also threadedly connected to the movable beam, the body of the first servo motor is fixedly connected to the top connecting plate, and the output shaft of the first servo motor is transmission-connected to the top end of the first screw rod.

3. The combined calibration device for an electronic crane scale according to claim 2, characterized in that: The beam driving mechanism also includes a guide column, which is fixed between the top connecting plate and the middle supporting plate, and the movable beam is slidably connected to the guide column.

4. The combined calibration device for an electronic crane scale according to claim 1, characterized in that: The superposition mechanism also includes a force equalizing plate. There are a plurality of standard sensors that are fixedly arranged along the circumferential direction of the substrate. The number of the pressure heads corresponds to the number of the standard sensors, and each of the pressure heads is fixedly connected to the force equalizing plate.

5. The combined calibration device for an electronic crane scale according to claim 1, characterized in that: The automatic loading and unloading mechanism of the electronic crane scale also includes a second screw rod, a second servo motor and a bearing seat. There are two bearing seats and they are respectively fixed at the two ends of the cantilever bracket. The two ends of the second screw rod are respectively rotatably connected to the bearing seats. The second screw rod passes through the movable seat and is threadedly connected. The body of the second servo motor is fixedly connected to one of the bearing seats, and the output shaft of the second servo motor is transmission connected to the second screw rod.

6. The combined calibration device for an electronic crane scale according to claim 5, characterized in that: The automatic loading and unloading mechanism of the electronic crane scale also includes a first linear guide rail and a first linear slider. The first linear guide rail is fixedly connected to the cantilever bracket, the first linear slider is fixedly connected to the moving seat, and the first linear slider is slidably connected to the first linear guide rail.

7. The combined calibration device for an electronic crane scale according to claim 1, characterized in that: It also includes a weight lifting drive mechanism, which includes a weight lifting plate, a third screw rod and a third servo motor, the top end of the third screw rod is rotatably connected to the middle support plate, the bottom end of the third screw rod is rotatably connected to the bottom plate, the third screw rod is also threadedly connected to the weight lifting plate, the body of the third servo motor is fixedly connected to the bottom plate, and the output shaft of the third servo motor is drivingly connected to the bottom end of the third screw rod; The weight assembly includes a weight connecting seat, a weight connecting sleeve, a weight connecting shaft, and a weight body with an inner hole. There are multiple weight bodies. The weight body at the top is fixedly connected to the weight connecting seat. The weight connecting seat is clamped on the lower end of the weight connecting piece. The weight connecting shaft and the weight connecting sleeve are arranged between the upper and lower adjacent weight bodies. The upper end of the weight connecting shaft is embedded in the inner hole of the upper weight body. The lower end of the weight connecting shaft is fixedly connected to the weight connecting sleeve by a thread. The weight connecting sleeve is also fixedly connected to the inner hole of the weight body below. The weight body at the bottom is placed on the upper surface of the weight lifting plate.

8. The combined calibration device for an electronic crane scale according to claim 7, characterized in that: It also includes a weight conveying mechanism, which includes a weight moving plate, a second linear guide, a second linear slider and a guide support column. The second linear guide is fixedly connected to the upper surface of the weight lifting plate, and the second linear guide is also fixedly connected to the guide support column. The second linear slider is fixedly connected to the lower surface of the weight moving plate. The second linear slider is slidably connected to the second linear guide, and the weight body at the bottom is placed on the upper surface of the weight moving plate.

9. The combined calibration device for an electronic crane scale according to claim 8, characterized in that: The weight conveying mechanism also includes a weight positioning seat, the bottom end of which is fixedly connected to the weight moving plate, and the top end of which can be inserted into the inner hole of the weight body at the bottom.

10. The combined calibration device for an electronic crane scale according to claim 1, characterized in that: It also includes an identification threshold testing mechanism, which includes a guide frame, a fourth screw rod, a test moving beam and a force sensor. The guide frame is fixedly connected to the lower surface of the intermediate support plate, the test moving beam is slidably connected to the guide frame up and down, both ends of the fourth screw rod are rotatably connected to the guide frame, the fourth screw rod is also threadedly connected to the test moving beam, the force sensor is fixedly connected to the test moving beam, the weight connecting piece passes through the force sensor and is slidably connected, and the weight connecting piece has a retaining ring, and the retaining ring is located below the force sensor.

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