Tightening tool torque calibration system and method

Abstract

The invention discloses a tightening tool torque calibration system and method.The tightening tool torque calibration system comprises a workbench and a clutch load control module arranged on the workbench, the clutch load control module comprises a hydraulic control assembly and a hydraulic clutch, a driving disc of the hydraulic clutch is detachably provided with an adapter, and the adapter is connected with the hydraulic control assembly; the adapter is provided with an insertion hole matched with a tightening tool to be calibrated, the clutch load control module is used for providing low-pressure stable ballast for the hydraulic clutch, and the hydraulic clutch is provided with a torque sensor used for measuring the real-time torque of the hydraulic clutch. On the one hand, accurate control over the working load of the hydraulic clutch can be achieved, more low-pressure control use occasions can be met, on the other hand, fine calibration of the tightening working torque can be achieved by means of the tightening tool torque calibration system and method, and high calibration precision and efficiency are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of ballast control, and particularly to a torque calibration system and method for a tightening tool. Background Art

[0002] Torque calibration of tightening tools is of extremely important significance, mainly reflected in ensuring operation safety, guaranteeing assembly quality, improving equipment reliability, and meeting the requirements of metrological traceability. Traditional torque calibration basically adopts the method of hard-contact direct measurement and calibration. For example, the patent with the patent number 2015205118809 and the name of torque wrench calibration device including a digital display device mainly realizes the manual calibration and automatic calibration of the torque wrench by connecting the gear shift reducer to the operating handle or motor through the gear shift lever, and mutually detects whether the calibration of the torque wrench is correct through manual calibration and automatic calibration, effectively improving the calibration accuracy of the torque wrench.

[0003] The applicant found in the research that the accuracy of the final calibration result of this type of calibration method is not good enough. Because in the actual process, the torque is often a gradually increasing process, especially when the tightened workpiece is used in combination with gaskets, springs, etc., the actual generated torque will also change. Therefore, it is urgent to further improve the current related equipment and methods. Summary of the Invention

[0004] In view of this, the present invention provides a torque calibration system and method for a tightening tool to solve the problem of poor torque calibration accuracy of the tightening tool in the prior art.

[0005] The technical solution is as follows:

[0006] A tool torque calibration system, characterized in that it includes a workbench and a clutch load control module arranged on the workbench. The clutch load control module includes a hydraulic control component and a hydraulic clutch. A adapter is detachably installed on the driving disk of the hydraulic clutch. The adapter has a jack adapted to the tightening tool to be calibrated. The clutch load control module is used to provide a low-pressure stable ballast to the hydraulic clutch, and a torque sensor for measuring its real-time torque is provided on the hydraulic clutch.

[0007] Adopting the above solution, by cleverly borrowing the working condition of variable hydraulic load of the hydraulic clutch and using it for the calibration of the tightening tool, the ballast can be adjusted according to needs, so as to simulate the actual use process of the tightening tool, which is beneficial to ensuring the accuracy of the calibration result.

[0008] Preferably: the hydraulic control component includes a circulating oil tank, a low-pressure oil cylinder, a servo motor and a control unit, wherein the low-pressure oil cylinder has a piston, the piston separates the low-pressure oil cylinder into an oil outlet chamber and an oil return chamber, the oil outlet chamber is connected to the oil inlet of the hydraulic clutch through an oil outlet pipeline, the oil return chamber is connected to the return oil pipeline A, a pressure sensor is provided on the oil outlet pipeline, the servo motor and the pressure sensor are both communicatively connected to the control unit, and the servo motor is used to drive the piston to move linearly in the low-pressure oil cylinder. By adopting the above scheme, during use, the servo motor can realize precise control of the working friction of the hydraulic clutch, that is, provide a more precise torque control strategy for the drive disk, which is particularly suitable for low oil pressure control and meets more testing requirements.

[0009] As a preferred embodiment: a solenoid valve is provided on the oil outlet pipeline, and the solenoid valve is communicatively connected with the control unit. The above solution is adopted to facilitate the realization of automatic control and improve the response speed.

[0010] Preferably, an oil replenishment pipeline is connected between the oil outlet cavity and the circulating oil tank, and an oil return pipeline B is connected between the oil outlet of the hydraulic clutch and the circulating oil tank. The above scheme can realize the recycling and reuse of hydraulic oil, improve the utilization efficiency, and facilitate the subsequent emptying operation of the clutch.

[0011] As a preferred embodiment, the hydraulic control assembly further comprises a mounting plate, and the circulating oil tank, the low-pressure oil cylinder and the servo motor are all mounted on the mounting plate. The above solution is adopted to facilitate modular installation and improve assembly and disassembly efficiency.

[0012] As a preferred embodiment, the workbench has a bottom table, a middle table and an operating table arranged in sequence from bottom to top, the hydraulic control assembly is installed on the bottom table, the hydraulic clutch is installed on the middle table, and a plurality of through holes for the jacks to be exposed are distributed on the operating table. With the above scheme, the overall layout is more reasonable, the center of gravity is at the bottom, it is more stable and reliable, and can meet the calibration and testing requirements of tightening tools of various specifications.

[0013] As a preferred embodiment, the operating table is provided with stopper components arranged one by one in correspondence with the through holes. The stopper components are used to stop the tightening tool to prevent accidental injuries caused by the swinging of the handle, thereby reducing the risk of use.

[0014] Preferably, the operating table has positioning pieces corresponding to the through holes, the adapter is provided with a bearing, the positioning piece is fixed on the operating table and fixedly connected to the outer ring of the corresponding bearing, and the adapter is higher than the upper surface of the positioning piece. The above scheme can achieve relative fixation of the end where the hydraulic clutch drive disc is located without hindering the normal rotation of the adapter, reduce the deflection or shaking, etc., which is conducive to further improving the accuracy of torque measurement.

[0015] A method for torque calibration of a tightening tool, the key lies in using the above-mentioned tightening tool torque calibration system and proceeding according to the following steps:

[0016] S1, set the working torque of the tightening tool;

[0017] S2, mate the output square head of the tightening tool with the socket of the adapter, and the stop component of the handle of the tightening tool is tightly pressed;

[0018] S3, start the tightening tool, and the output square head drives the driving disc of the hydraulic clutch to rotate through the adapter;

[0019] S4, the servo motor works at the set speed, sends the hydraulic oil in the oil outlet chamber of the low-pressure oil cylinder into the oil cylinder of the hydraulic clutch, and after reaching the pressure set value or / and the displacement set position, the servo motor enables and maintains;

[0020] S5, record the real-time torque measured by the torque sensor;

[0021] S6, perform data processing on the recorded real-time torque and the set working torque.

[0022] Preferably: before performing step S3, first empty the hydraulic clutch and the oil pipeline. Adopting the above solution can further improve the hydraulic control accuracy, reduce or avoid air interference, and is beneficial to ensuring the measurement accuracy.

[0023] Compared with the prior art, the beneficial effects of the present invention are:

[0024] By using a tightening tool torque calibration system and method provided by the present invention, it is possible to achieve precise control of the working load of the hydraulic clutch, meet more low-pressure control application scenarios. On the other hand, with the help of the tightening tool torque calibration system and method, it is possible to achieve refined calibration of the tightening working torque, with high calibration accuracy and efficiency, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a schematic structural diagram of the tightening tool torque calibration system of the present invention;

[0026] Figure 2 is Figure 1 front view;

[0027] Figure 3 is an installation cross-sectional view of the hydraulic clutch on the workbench;

[0028] Figure 4 is a schematic installation structure diagram of the hydraulic control component part;

[0029] Figure 5 is a schematic structural diagram of the hydraulic clutch;

[0030] Figure 6 It is a schematic diagram of the hydraulic oil circuit control;

[0031] Figure 7 It is a schematic diagram of the control unit block diagram;

[0032] Figure 8 It is a schematic diagram of the test result

[0033] Figure 9 It is a schematic diagram of the change of the pressure curve during the calibration process of the tightening tool torque calibration system using the valve in this invention;

[0034] Figure 10 It is a schematic diagram of the structure of the tightening tool. Specific implementation mode

[0035] The present invention will be further described in detail below with reference to the accompanying drawings.

[0036] Reference Figures 1 to 9 A tightening tool torque calibration system and method as shown. The tightening tool torque calibration system mainly includes a workbench 300 and a clutch load control module installed on the workbench 300. The clutch load control module is used to provide a low-pressure stable ballast to the hydraulic clutch 200. As shown in the figure, it mainly includes a hydraulic control component 100 and a hydraulic clutch 200. The hydraulic control component 100 includes a circulating oil tank 110, a low-pressure oil cylinder 120, a servo motor 130 and a control unit 140. As shown in the figure, there is a piston 121 in the low-pressure oil cylinder 120. The piston 121 divides the low-pressure oil cylinder 120 into two relatively independent chambers, which are an oil outlet chamber 122 and an oil return chamber 123 respectively. The oil outlet chamber 122 is communicated with the oil inlet of the hydraulic clutch 200 through an oil outlet pipeline 124. The oil return chamber 123 is connected with an oil return pipeline A125. During implementation, the oil return pipeline A125 is also connected to the circulating oil tank 110. A pressure sensor 170 is provided on the oil outlet pipeline 124. The servo motor 130 and the pressure sensor 170 are both communicatively connected to the control unit 140. The servo motor 130 is used to drive the piston 121 to move linearly in the low-pressure oil cylinder 120.

[0037] During operation, the servo motor 130 is preferably a servo push rod motor. Its push rod extends into the low-pressure oil cylinder 120, is fixedly connected to the piston 121, and has a sliding seal structure with the low-pressure oil cylinder 120. When the piston 121 moves towards the position where it is communicated with the oil outlet pipeline 124, the hydraulic oil in the oil outlet chamber 122 can be pressed into the oil cylinder of the hydraulic clutch 200, so that the piston disk moves, gradually increasing the contact load of the friction plates, and thus changing the torque load that its driving disk can bear. Because the hydraulic pressure is controlled by the servo motor 130, and the servo motor 130 can be better automated controlled, this structure can better meet the refined control of the clutch load, and the overall response is faster and more stable.

[0038] There is a makeup oil pipeline 126 connected between the oil outlet chamber 122 and the circulating oil tank 110, which is mainly used to supplement hydraulic oil into the oil outlet chamber 122. There is an oil return pipeline B127 connected between the oil outlet of the hydraulic clutch 200 and the circulating oil tank 110, which is mainly used to discharge the hydraulic oil in the hydraulic clutch 200. In addition, in this embodiment, a solenoid valve 150 is provided on the oil outlet pipeline 124, and the solenoid valve 150 is communicatively connected to the control unit 140. The on-off control of the pipeline can be better carried out through the solenoid valve 150. Similarly, corresponding electrically controlled valves can also be provided on the oil return pipeline A125, the makeup oil pipeline 126 and the oil return pipeline B127 for quick control.

[0039] Furthermore, to improve the disassembly and assembly efficiency, the clutch load control module further includes a mounting plate 160, and the circulating oil tank 110, the low-pressure oil cylinder 120 and the servo motor 130 are all mounted on the mounting plate 160.

[0040] As shown in the figure, the clutch load control module is mounted on the workbench 300. A adapter 210 is detachably mounted on the driving disc of the hydraulic clutch 200. The adapter 210 has a jack 211 adapted to the calibration tightening tool. Usually, the output end of the calibration tightening tool is a square head structure, so the jack 211 is a corresponding square hole. At the same time, a torque sensor for measuring its real-time torque is provided on the hydraulic clutch 200. The torque sensor is communicatively connected to the control unit 140. In the actual implementation process, it can be measured in combination with an encoder, which is mainly used to accurately collect the torque generated by the reaction of the driving disc of the hydraulic clutch 200.

[0041] Focus on Figures 1 to 3 , the workbench 300 is a box structure, and its interior has a bottom table surface 310, an intermediate table surface 320 and an operation table surface 330 arranged in sequence from bottom to top. During specific installation, the hydraulic control assembly 100 is mainly mounted on the bottom table surface 310, while the hydraulic clutch 200 is mounted on the intermediate table surface 320. A plurality of through holes 331 for the jack 211 to expose are distributed on the operation table surface 330.

[0042] In this embodiment, a stop member 340 (only one is shown in the figure) corresponding to the through hole 331 is provided on the operation table surface 330. The stop member 340 is a vertically arranged rod-shaped body, which is fixed on the operation table surface 330 in a detachable manner and is located on the circumferential outside of the through hole 331. It is mainly used to stop the handle of the tightening tool during testing to avoid its rotation and ensure that the output square head can transmit the rotational torque to the adapter 210.

[0043] In addition, there are positioning members 350 on the operation table surface 330 that are arranged in one-to-one correspondence with the through holes 331. As specifically shown in the figure, the positioning member 350 is a cylindrical structure with a cross-section generally in the shape of a T. A bearing 220 is sleeved on the adapter 210. The upper end of the positioning member 350 is fixed on the operation table surface 330 and is fixedly connected to the outer ring of the corresponding bearing 220, that is, in interference fit with the outer ring of the bearing 220. The adapter 210 is slightly higher than the upper surface of the positioning member 350. In this way, the positioning member 350 actually forms a stable support for the upper end of the hydraulic clutch 200, which can effectively reduce or avoid polarization, thereby further improving the detection and calibration accuracy.

[0044] On the other hand, to facilitate the quick disassembly and assembly of the hydraulic clutch 200, the hydraulic clutch 200 has a base 230, and a handle 240 is provided on the base 230. The handle 240 is vertically arranged, and the hydraulic clutch 200 can be directly grasped by the handle 240 and placed horizontally.

[0045] In this application, based on the above tightening tool torque calibration system, a corresponding tightening tool torque calibration method is given, which mainly includes the following steps:

[0046] The first step is to set the working torque of the tightening tool. It should be noted that the tightening tool mentioned in this application is a sensor-type tightening tool, and within the designed torque range, the required output torque can be set as needed.

[0047] The second step is to fit the output square head of the tightening tool with the jack 211 of the adapter 210, that is, insert the output square head into the jack 211, and ensure that the handle of the tightening tool abuts against the stop member 340 to avoid being thrown out during the startup moment.

[0048] The third step is to start the tightening tool, and the output square head drives the driving disk of the hydraulic clutch 200 to rotate through the rotation of the adapter 210;

[0049] The fourth step is that the servo motor 130 operates at the set speed, and sends the hydraulic oil in the oil outlet cavity 122 of the low-pressure oil cylinder 120 into the oil cylinder of the hydraulic clutch 200. Until the pressure set value or / and the displacement set value is reached, a position switch is provided on the corresponding servo motor 130, and the position switch is also communicatively connected to the control unit 140. The servo motor 130 keeps working to ensure that the piston position in the low-pressure oil cylinder 120 remains unchanged, that is, to maintain the stability of the oil cylinder pressure in the hydraulic clutch 200.

[0050] The fifth step is to record the real-time torque measured by the torque sensor.

[0051] The sixth step is to perform data processing on the recorded real-time torque and the set working torque. This step mainly calculates the mean and the mean range, so as to obtain the error value of the corresponding tightening tool for error elimination or calibration, etc.

[0052]

[0052] During specific implementation, before performing the third step, the hydraulic clutch 200 and the oil outlet pipeline 124 are first emptied. Specifically, the servo motor 130 operates, and low-pressure oil enters the cylinder of the hydraulic clutch 200 through the oil outlet pipeline 124. At the same time, the valve on the oil return pipeline B127 connected to the oil outlet of the hydraulic clutch 200 is opened. This is repeated multiple times to discharge the air in the oil outlet pipeline 124 and the cylinder of the hydraulic clutch 200, thereby avoiding the pressure error caused by air.

[0053] Reference Figures 1 to 9 Figures 1 to 9 The tightening tool torque calibration system and method shown in the figure. During specific implementation, the control unit 140 mainly includes an upper industrial computer system and an MCU. The MCU is mainly used to collect pressure data and torque values, and send corresponding commands to the servo motor, solenoid valve, etc. In combination with the calibration process, the rotation signal of the hydraulic clutch can also be collected and transmitted to the MCU for further rapid response. The upper computer industrial control system mainly includes a display and read / write module and a data processing module. The display and read / write module is mainly used to write relevant information for calibration tightening basis and display the relevant information read and written. It usually includes components such as a display, keyboard, and mouse. The data processing module mainly processes the measured torque value and the set working torque (i.e., nominal torque), including mean and range mean calculations, and curve plotting, etc.

[0054] As shown in the figure, the tightening tool with model C9611682 is detected and calibrated using the present invention. As shown in the figure, the set nominal torque value is 22 N·m. After calculating 30 groups of data, the mean value is 21.874, and the range mean value is 0.750. Based on these values, the error of the tightening tool can be directly adjusted to ensure the actual torque accuracy during subsequent use as much as possible. The change in ballast during the measurement process can be referenced Figure 9 Figure 9 shown in the figure. By simulating elastic components during the gradual pressure increase process, the measurement accuracy can be greatly improved.

[0055] Finally, it should be noted that the above description is only the preferred embodiment of the present invention. Under the inspiration of the present invention, those of ordinary skill in the art can make various similar representations without violating the purpose and claims of the present invention. Such transformations all fall within the protection scope of the present invention.

Claims

1. A tightening tool torque calibration system, characterized in that: The invention comprises a workbench (300) and a clutch load control module arranged on the workbench (300), wherein the clutch load control module comprises a hydraulic control assembly (100) and a hydraulic clutch (200), an adapter (210) is detachably mounted on a drive disc of the hydraulic clutch (200), the adapter (210) having a socket (211) adapted to a tightening tool to be calibrated, the clutch load control module is used to provide a low-pressure stable ballast to the hydraulic clutch (200), and the hydraulic clutch (200) is provided with a torque sensor for measuring its real-time torque.

2. The tightening tool torque calibration system according to claim 1, characterized in that: The hydraulic control assembly (100) comprises a circulating oil tank (110), a low-pressure oil cylinder (120), a servo motor (130) and a control unit (140), wherein the low-pressure oil cylinder (120) has a piston (121) therein, the piston (121) divides the low-pressure oil cylinder (120) into an oil outlet chamber (122) and an oil return chamber (123), the oil outlet chamber (122) is connected to an oil inlet of a hydraulic clutch (200) via an oil outlet pipeline (124), the oil return chamber (123) is connected to an oil return pipeline A (125), a pressure sensor (170) is provided on the oil outlet pipeline (124), the servo motor (130) and the pressure sensor (170) are both communicatively connected to the control unit (140), and the servo motor (130) is used to drive the piston (121) to move linearly in the low-pressure oil cylinder (120).

3. The tool torque calibration system according to claim 2, characterized in that: The oil outlet pipeline (124) is provided with a solenoid valve (150), and the solenoid valve (150) is communicatively connected with the control unit (140).

4. The tightening tool torque calibration system according to claim 2 or 3, characterized in that: An oil replenishment pipeline (126) is connected between the oil outlet chamber (122) and the circulating oil tank (110), and an oil return pipeline B (127) is connected between the oil outlet of the hydraulic clutch (200) and the circulating oil tank (110).

5. The tightening tool torque calibration system according to claim 2 or 3, characterized in that: The hydraulic control assembly further comprises a mounting plate (160), and the circulating oil tank (110), the low-pressure oil cylinder (120) and the servo motor (130) are all mounted on the mounting plate (160).

6. The tightening tool torque calibration system according to claim 2, characterized in that: The workbench (300) comprises a bottom table (310), an intermediate table (320) and an operating table (330) which are arranged in sequence from bottom to top; the hydraulic control assembly (100) is mounted on the bottom table (310); the hydraulic clutch (200) is mounted on the intermediate table (320); and a plurality of through holes (331) for exposing the plug holes (211) are distributed on the operating table (330).

7. The tightening tool torque calibration system according to claim 6, characterized in that: The operating table (330) is provided with stopper components (340) arranged in one-to-one correspondence with the through holes (331).

8. The tightening tool torque calibration system according to claim 6 or 7, characterized in that: The operating table (330) is provided with positioning pieces (350) arranged in one-to-one correspondence with the through holes (331); the adapter (210) is sleeved with a bearing (220); the positioning piece (350) is fixed on the operating table (330) and fixedly connected to the outer ring of the corresponding bearing (220); the adapter (210) is higher than the upper surface of the positioning piece (350).

9. A method for calibrating torque of a tightening tool, characterized in that: The tightening tool torque calibration system as claimed in any one of claims 1 to 9 is adopted and carried out according to the following steps: S1, set the working torque of the tightening tool; S2, the output square head of the tightening tool is matched with the socket (211) of the adapter (210), and the handle of the tightening tool is pressed tightly with a stopper component (340); S3, starting the tightening tool, the output square head rotates through the adapter (210) to drive the driving disk of the hydraulic clutch (200) to rotate; S4, the servo motor (130) operates at a set speed to deliver the hydraulic oil in the oil outlet chamber (122) of the low-pressure oil cylinder (120) into the oil cylinder of the hydraulic clutch (200), until the pressure setting value and / or the displacement setting position are reached, and the servo motor (130) is enabled and maintained; S5, recording the real-time torque measured by the torque sensor; S6, performing data processing on the recorded real-time torque and the set working torque.

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