A high-power dynamometer torque metering and calibrating device

Abstract

The utility model discloses a kind of high-power dynamometer torque measurement calibration device, including lever, standard dynamometer, hydraulic force applying device and display control terminal, the lever one end is connected with the output shaft of high-power dynamometer by connecting flange, the standard dynamometer is arranged in lever other end, and respectively with lever movable connection, hydraulic force applying device fixed connection and display control terminal communication connection, the display control terminal is electrically connected with hydraulic force applying device;The pressure head of the standard dynamometer is conical pressure head, conical force applying hole matched with conical pressure head is set on the lever, and the taper angle of conical force applying hole is greater than the taper angle of conical pressure head.The utility model has the advantages of: it can guarantee the precision and constant of force arm length;Standard dynamometer can be applied to accurate, stable pressure, and the fluctuation degree is small, convenient for on-site measurement;It can eliminate the error introduced by lever inclination, improve the accuracy of calibration result.

Description

Technical Field

[0001] This utility model relates to the field of dynamometer calibration technology, specifically to a torque measurement and calibration device for a high-power dynamometer. Background Technology

[0002] A dynamometer, as a specialized testing device for the output performance of rotating power sources, can test the speed, torque, and output power of power sources such as internal combustion engines, electric motors, and water turbines. A dynamometer mainly consists of three parts: a loader, a speed sampling unit, and a torque sensor. Dynamometers are mainly classified into eddy current dynamometers, hydraulic dynamometers, magnetic particle dynamometers, and electric dynamometers, and their applications include automotive chassis engines, aerospace engines, and marine engines.

[0003] Currently, high-power dynamometers in China can measure torque up to 100 kNm, and even 1000 kNm. Traditionally, dynamometer torque calibration typically uses a lever and weight method, but this applies only a small torque and is generally suitable for low-power dynamometers, failing to meet the calibration requirements of high-power dynamometers. While some metrology institutions now use levers, standard force gauges, and jacks to calibrate high-power dynamometers, this method has the following problems:

[0004] (1) The pressure head of the standard force gauge is a cylindrical pressure head, that is, the pressure head surface is a circular plane. During each calibration, the loading point cannot be constant, which makes it impossible to accurately measure the key length (i.e., lever arm) between the loading point (i.e., the point of force application) and the center of the lever (i.e., the fulcrum). Since torque = force * lever arm, the length (i.e., the lever arm) between the center of the lever (i.e., the fulcrum) and the center of the pressure head of the standard force gauge is a key indicator.

[0005] (2) As a force source, the jack is very unstable in applying force and has obvious leakage problems, which seriously affect the accurate measurement of the value;

[0006] (3) High-power dynamometers require the application of torques of hundreds of thousands of Nm, causing the lever to change from an initial horizontal state to a significantly tilted state. The resulting error is not considered. During calibration, the lever must be horizontal for accurate measurement. However, under full-scale load, the assembly clearance and deformation of the lever inevitably cause it to tilt, changing from an initial horizontal state to a significantly tilted state. This tilt angle leads to a change in the lever arm length. If the tilt angle reaches 5°, it can introduce a 0.4% error, severely affecting the calibration results. Therefore, the tilt angle at each calibration point must be included in the calculation to avoid the introduced error. However, existing high-power dynamometer torque measurement and calibration methods do not emphasize the impact of the tilt angle on the calibration results and neglect the measurement of the tilt angle. Utility Model Content

[0007] The purpose of this invention is to provide a high-power dynamometer torque measurement and calibration device with constant loading point, stable force application, and small error, in order to solve the technical problems existing in the background art.

[0008] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0009] A torque measurement and calibration device for a high-power dynamometer includes a lever, a standard force gauge, a hydraulic force application device, and a display and control terminal. One end of the lever is connected to the output shaft of the high-power dynamometer via a connecting flange. The standard force gauge is located at the other end of the lever and is movably connected to the lever, fixedly connected to the hydraulic force application device, and communicatively connected to the display and control terminal. The display and control terminal is electrically connected to the hydraulic force application device. The pressure head of the standard force gauge is a conical pressure head. The lever is provided with a conical force application hole that mates with the conical pressure head, and the cone angle of the conical force application hole is larger than the cone angle of the conical pressure head.

[0010] Furthermore, it also includes an inclinometer, which is pre-embedded in the upper part of the lever near the end of the standard force gauge and is communicatively connected to the display and control terminal.

[0011] Furthermore, the plurality of conical force-applying holes are pre-drilled at the lower part of the lever near the end of the standard force gauge.

[0012] Furthermore, the hydraulic force application device includes a hydraulic cylinder, an electromagnetic directional valve, a servo motor, a hydraulic pump, and a hydraulic tank. The standard force gauge is fixedly mounted at the end of the piston rod of the hydraulic cylinder. The electromagnetic directional valve is connected to the hydraulic cylinder, the hydraulic pump, and the hydraulic tank via hydraulic pipes. The hydraulic pump is also connected to the hydraulic tank via hydraulic pipes. The hydraulic pump is also connected to the servo motor via a coupling. The electromagnetic directional valve and the servo motor are both electrically connected to the display and control terminal.

[0013] Furthermore, the standard force gauge is connected to the display and control terminal via Bluetooth.

[0014] Furthermore, the inclinometer and the display and control terminal are connected via Bluetooth.

[0015] Furthermore, the standard force gauge employs a force sensor.

[0016] Furthermore, the display and control terminal can be any one of a laptop computer, a smartphone, or a desktop computer.

[0017] Compared with the prior art, the advantages of this utility model are as follows:

[0018] (1) By designing the pressure head of the standard force gauge as a cone shape and matching it with the cone-shaped force application hole reserved on the lever, the accuracy and constant length of the lever arm can be guaranteed.

[0019] (2) A hydraulic force application device is used as the force source. The hydraulic oil pump is controlled by a servo motor in a closed loop to accurately control the oil inlet and outlet. It can apply precise and stable pressure to the standard force measuring instrument with small fluctuations, which is convenient for on-site measurement.

[0020] (3) By embedding an inclinometer in the lever to read the inclination angle of the lever in real time, and incorporating the inclination angle at each calibration point into the calculation, the error introduced by the inclinometer can be avoided from affecting the accuracy of the calibration results. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in this embodiment, the accompanying drawings used in the description of the embodiment will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the structure of the high-power dynamometer torque measurement and calibration device according to an embodiment of the present invention;

[0023] Figure 2 yes Figure 1 A magnified view of a portion of the image;

[0024] Figures 3-5 This is a schematic diagram of the hydraulic principle of the hydraulic force application device involved in the embodiment of this utility model;

[0025] Explanation of reference numerals in the attached diagram: 1. Lever; 2. Standard force gauge; 3. Hydraulic force application device; 301. Hydraulic cylinder; 302. Electromagnetic directional valve; 303. Servo motor; 304. Hydraulic oil pump; 305. Hydraulic oil tank; 4. Display and control terminal; 5. Conical force application hole; 6. Conical pressure head; 7. Inclinometer; 8. Connecting flange; 9. High-power dynamometer. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can typically be arranged and designed in various different configurations.

[0027] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0028] In the description of the embodiments of this utility model, it should be noted that if terms such as "upper," "lower," "horizontal," or "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product is in use, they are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this utility model. Furthermore, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance. In addition, the appearance of the term "horizontal" does not mean that the component is required to be absolutely horizontal, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but rather that it can be slightly tilted.

[0029] In the description of the embodiments of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0030] The present invention will be further described below with reference to the accompanying drawings:

[0031] See Figure 1 and Figure 2This utility model provides a torque measurement and calibration device for a high-power dynamometer, including a lever 1, a standard force gauge 2, a hydraulic force application device 3, and a display and control terminal 4. One end of the lever 1 is connected to the output shaft of a high-power dynamometer 9 via a connecting flange 8. The standard force gauge 2 is located at the other end of the lever 1 and is movably connected to the lever 1, fixedly connected to the hydraulic force application device 3, and communicatively connected to the display and control terminal 4. The standard force gauge 2 is used to apply force to the lever 1. The display and control terminal 4 is electrically connected to the hydraulic force application device 3 and is used to collect and display the force value of the standard force gauge 2 and control the operation of the hydraulic force application device 3. The pressure head of the standard force gauge 2 is a conical pressure head 6. The lever 1 is provided with a conical force application hole 5 that cooperates with the conical pressure head 6, and the cone angle of the conical force application hole 5 is greater than the cone angle of the conical pressure head 6, so that the conical pressure head 6 of the standard force gauge 2 has appropriate room for movement in the conical force application hole 5 when the lever 1 is tilted at a small angle.

[0032] Specifically, to reduce the error introduced by the tilt of lever 1 and its impact on the calibration results, the high-power dynamometer torque measurement and calibration device provided in this embodiment of the invention also includes an inclinometer 7. The inclinometer 7 is pre-embedded in the upper part of lever 1 near the end of the standard force gauge 2 and is communicatively connected to the display and control terminal 4. The inclinometer 7 is used to measure and read the tilt angle of the lever in real time.

[0033] Specifically, to better adapt to the complex calibration environment on site and avoid the problem of unsuitable force application conditions caused by only setting one force application hole position without a suitable load-bearing surface directly below it, the high-power dynamometer torque measurement calibration device provided in this embodiment of the invention requires at least one conical force application hole 5 to be reserved on the lever 1. This allows for the replacement of a suitable force application hole position if one does not meet the requirements. For example, if the arm length of the lever 1 is 1m, three conical force application holes 5 with arm lengths of 0.5m, 0.75m, and 1m can be set on the lever 1 respectively. If the arm length of the lever 1 is 2m, seven conical force application holes 5 with arm lengths of 0.5m, 0.75m, 1m, 1.25m, 1.5m, 1.75m, and 2m can be set on the lever 1 respectively.

[0034] It should be understood that the arm length of lever 1, the number and position of conical force application holes 5 can all be adjusted according to actual needs.

[0035] Specifically, see Figure 1 , Figures 3 to 5The hydraulic force application device 3 includes a hydraulic cylinder 301, an electromagnetic directional valve 302, a servo motor 303, a hydraulic pump 304, and a hydraulic oil tank 305. A standard force gauge 2 is fixedly mounted at the end of the piston rod of the hydraulic cylinder 301, allowing adjustment of its height by extending or retracting the cylinder. The electromagnetic directional valve 302 is connected to the hydraulic cylinder 301, hydraulic pump 304, and hydraulic oil tank 305 via hydraulic pipes, controlling the extension and retraction of the hydraulic cylinder 301. The hydraulic pump 304 is also connected to the hydraulic oil tank 305 via hydraulic pipes and a coupling to the servo motor 303. Both the electromagnetic directional valve 302 and the servo motor 303 are electrically connected to the display and control terminal 4. In practical applications, the size and weight of the hydraulic force application device 3 are minimized for easy on-site transport. Figure 3 The diagram shows the hydraulic principle of the hydraulic force application device 3 in a non-working state; Figure 4 The diagram shown is a hydraulic schematic diagram of the hydraulic cylinder 301 in the hydraulic force application device 3 when it is in the lifting state. Figure 5 The diagram shows the hydraulic principle of the hydraulic cylinder 301 in the hydraulic force application device 3 when it is in the retracted state.

[0036] More specifically, the standard force gauge 2 and the display and control terminal 4 are connected via Bluetooth.

[0037] More specifically, the inclinometer 7 and the display and control terminal 4 are connected via Bluetooth.

[0038] More specifically, the standard force gauge 2 uses a force sensor, such as the HBM force sensor.

[0039] More specifically, the display and control terminal 4 can be any one of a laptop, smartphone, or desktop computer.

[0040] The high-power dynamometer torque measurement and calibration device provided in this embodiment operates on the following principle:

[0041] (1) Before use, install lever 1 and ensure that lever 1 is horizontal. Use inclinometer 7 to determine the horizontal state of lever 1.

[0042] (2) Based on the on-site calibration situation, select one conical force application hole 5 as the loading hole position of the standard force measuring instrument 2, install the standard force measuring instrument 2 and the hydraulic cylinder 301 in the hydraulic force application device 3, and ensure that the conical pressure head 6 of the standard force measuring instrument 2 and the selected conical force application hole 5 on the lever 1 are gently in contact.

[0043] (3) Zero the indicator device of the high-power dynamometer 9, apply torque to the upper limit value and then remove the torque, check the zeroing status of its indicator device, and readjust to zero;

[0044] (4) Within the specified measurement range, first set the calibration points of the high-power dynamometer 9 (calibrate no less than 8 points, with each calibration point evenly distributed), then control the hydraulic force application device 3 through the display and control terminal 4 to apply torque step by step to the upper limit value according to the set calibration points, and then gradually remove the torque. During this process of gradually applying and removing torque, the display and control terminal 4 collects the force value of the standard force gauge 2 and the angle value of the inclinometer 7 in real time via Bluetooth, and calculates the corresponding torque calibration value. This process is repeated n times, where n≥3;

[0045] Among them, torque calibration value Calculate using the following formula:

[0046] (1)

[0047] In the above formula (1), Indicates the force value of a standard force gauge; This indicates the length from the fulcrum of the lever to the conical force-applying hole, i.e., the lever arm length; Indicates the angle of inclination of the lever.

[0048] (5) Calculate the torque indication error of the high-power dynamometer and repetitiveness ;

[0049] Among them, the torque indication error Calculate using the following formula:

[0050] (2)

[0051] Among them, torque indication repeatability Calculate using the following formula:

[0052] (3)

[0053] In equations (2) and (3) above, This represents the arithmetic mean of n torque readings from a high-power dynamometer. This represents the arithmetic mean of n torque calibration values ​​from the high-power dynamometer torque metering and calibration device. This indicates the upper limit of the torque measurement range of a high-power dynamometer; and This represents the maximum and minimum torque readings of a high-power dynamometer during n readings. Indicates a citation error;

[0054] (6) Based on the torque indication error of the high-power dynamometer in (5) and repetitiveness The calculation results are used to determine the accuracy level of torque measurement for the high-power dynamometer.

[0055] For example, the torque indication error of a high-power dynamometer is within ±1%FS, the torque indication repeatability is within 1%FS, and the torque measurement accuracy meets Class 1 or Class C standards.

[0056] Finally, it should be noted that the above description is only an embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent structural or procedural transformations made based on the content of this utility model specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A torque measurement and calibration device for a high-power dynamometer, characterized in that: The device includes a lever (1), a standard force gauge (2), a hydraulic force application device (3), and a display and control terminal (4). One end of the lever (1) is connected to the output shaft of a high-power dynamometer (9) via a connecting flange (8). The standard force gauge (2) is located at the other end of the lever (1) and is movably connected to the lever (1), fixedly connected to the hydraulic force application device (3), and communicatively connected to the display and control terminal (4). The display and control terminal (4) is electrically connected to the hydraulic force application device (3). The pressure head of the standard force gauge (2) is a conical pressure head (6). The lever (1) is provided with a conical force application hole (5) that cooperates with the conical pressure head (6), and the cone angle of the conical force application hole (5) is greater than the cone angle of the conical pressure head (6).

2. The high-power dynamometer torque measurement and calibration device according to claim 1, characterized in that: It also includes an inclinometer (7), which is pre-embedded in the upper part of the lever (1) near the standard force gauge (2) and is connected to the display and control terminal (4) for communication.

3. The high-power dynamometer torque measurement and calibration device according to claim 1, characterized in that: The conical force application hole (5) is reserved in the lower part of the lever (1) near the standard force measuring instrument (2).

4. The high-power dynamometer torque measurement and calibration device according to claim 1, characterized in that: The hydraulic force application device (3) includes a hydraulic cylinder (301), an electromagnetic reversing valve (302), a servo motor (303), a hydraulic pump (304), and a hydraulic tank (305). The standard force gauge (2) is fixedly installed at the piston rod end of the hydraulic cylinder (301). The electromagnetic reversing valve (302) is connected to the hydraulic cylinder (301), the hydraulic pump (304), and the hydraulic tank (305) through hydraulic pipes. The hydraulic pump (304) is also connected to the hydraulic tank (305) through hydraulic pipes. The hydraulic pump (304) is also connected to the servo motor (303) through a coupling. The electromagnetic reversing valve (302) and the servo motor (303) are both electrically connected to the display and control terminal (4).

5. The high-power dynamometer torque measurement and calibration device according to claim 1, characterized in that: The standard force gauge (2) and the display and control terminal (4) are connected via Bluetooth.

6. The high-power dynamometer torque measurement and calibration device according to claim 2, characterized in that: The inclinometer (7) and the display and control terminal (4) are connected via Bluetooth.

7. The high-power dynamometer torque measurement and calibration device according to any one of claims 1 to 6, characterized in that: The standard force gauge (2) uses a force sensor.

8. The high-power dynamometer torque measurement and calibration device according to any one of claims 1 to 6, characterized in that: The display and control terminal (4) can be any one of a laptop computer, a smartphone, or a desktop computer.

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