Force value calibration device of small-range stiffness tester

Abstract

The utility model provides a force value calibration device of a small-range stiffness tester, which comprises a counter-force frame which comprises two counter-force plates, an upper cross beam, a lower cross beam and a vertical plate, the two counter-force plates are vertically arranged and are parallel to each other; the upper cross beam and the lower cross beam are respectively arranged at the upper and lower ends of the two counter-force plates, the vertical plate is arranged between the two counter-force plates, and the upper and lower ends of the vertical plate are arranged in the middle of the upper cross beam and the lower cross beam; the transverse screw rod is parallel to the upper cross beam and the lower cross beam, one end of the transverse screw rod is movably arranged on the vertical plate in a penetrating manner, and the other end of the transverse screw rod is movably arranged on one counter-force plate in a penetrating manner; the dynamometer is arranged at the end part of the transverse screw rod on the outer side of the counter-force plate; the reversing mechanism assembly is connected with the middle part of the transverse screw rod; the lower end of the rotating shaft is connected with the reversing mechanism assembly, and the upper end of the rotating shaft penetrates out of the upper beam. The device is simple in structure, convenient to operate and good in universality, test values can be directly observed, and convenience and accuracy of test calibration are effectively improved.

Description

Technical Field

[0001] The utility model relates to a force value calibration device for a small-range stiffness tester.

Background Art

[0002] Stiffness is an index for measuring light industrial materials with a specific thickness, which is determined by measuring the resistance of the material when it is subjected to a certain bending force. This resistance can be expressed in two ways: one is the resistance when the test specimen reaches a certain bending angle, with the unit of N; the other is the product of the resistance and the test length, with the unit of N·m. And the cup body stiffness belongs to the index of the first kind of resistance mentioned above.

[0003] Specifically, the cup body stiffness refers to the maximum force received when, along the opposite side walls of the cup body, at a position about two-thirds of the cup body height, a force is uniformly applied in the diameter direction at a relative speed of (50.0±2.5) mm / min, until the total deformation of the cup side wall reaches (9.5±0.5) mm. The cup body stiffness tester is designed according to the principle requirements of the mechanical paper cup body stiffness tester in the QB / T2294—1997 "Paper Cups" standard of the light industry. The specific structure is as Figure 1 shown, including a stiffness tester body 1', a test head 2', a top head 3', a fixed table 4', and a display screen 5'. The forward and backward movements of the test head of this instrument are driven by a motor, the travel of the test head is measured by an encoder, the cup body resistance is measured by a small-range force sensor, and the control, data, measurement, and calculation processing of all actions are completed by a computer and displayed on the display screen, and the test report is printed by a printer. This instrument is a fully automatic electronic test instrument, which is very convenient to use and has a wide test range. It is mainly used for measuring the cup body stiffness of various capacity paper cups, and can also be used for measuring the stiffness of other material cups and bowls such as plastics and edible powder moldings. It is an ideal cup and bowl stiffness detection instrument.

[0004] For the cup body of a paper cup, the key parameter for the accuracy of its stiffness tester is the test force value. Since the range of the test force of the tester is small (generally not exceeding 50 N) and it does not have the function of controllable microloading, a high-accuracy force measuring instrument without an auxiliary force transmission mechanism cannot be directly used for calibration. The current calibration method is based on JJF (Light Industry) 111—2018 "Calibration Specification for Paper Cup Body Stiffness Tester". The instrument is flipped 90°, the probe installed on the small-range force sensor is vertically upward, a plastic support is installed on the probe, the instrument indication is set to zero, and a force value weight is used for calibration; the relative error of the force value also needs to meet the requirements in this calibration specification. However, this method has three obvious disadvantages: First, the force value weight does not directly apply gravity to the tester sensor, but indirectly acts on the tester sensor through the plastic support and the test head. In this case, the coaxiality between the plastic support, the test head and the tester sensor must be extremely small, and the levelness of the force-receiving surface of the tester sensor must also be extremely small, so that the nominal value of the force value weight can be used as the standard value. However, the tester sensor is actually installed inside the instrument, making it difficult to measure the coaxiality and levelness; Second, according to the calibration specification, five force value calibration points that are roughly evenly distributed need to be selected within the range of 10% to 90% of the upper limit value of the force value measurement range. Since the measurement ranges of testers of different manufacturers and models are different, many force value weights of different specifications and sizes often need to be prepared for on-site calibration, which is not easy to carry; Third, the whole tester needs to be flipped, which is very inconvenient to operate due to its large self-weight and irregular external structure, and it is also easy to damage the instrument itself.

Utility Model Content

[0005] The technical problem to be solved by the present utility model is to provide a force value calibration device for a small-range stiffness tester, which has a simple structure, is easy to operate, has good general performance, and can directly observe the test value. It overcomes the problems of traditional force value weights being not easy to carry and difficult to calibrate, and the placement and force state of the device are similar to the actual cup and bowl sample state, effectively improving the convenience and accuracy of test calibration. In addition, the force value calibration device of the present utility model or its sensor can be calibrated by a force standard machine or a force sensor calibration device.

[0006] The present utility model is implemented as follows:

[0007] A force value calibration device for a small-range stiffness tester, comprising:

[0008] A reaction frame, the reaction frame includes two reaction plates, an upper cross beam, a lower cross beam and a vertical plate. The two reaction plates are arranged vertically and are parallel to each other; the upper cross beam and the lower cross beam are respectively fixedly arranged at the upper and lower ends of the two reaction plates, the vertical plate is arranged between the two reaction plates, and the upper and lower ends of the vertical plate are respectively vertically arranged at the middle parts of the upper cross beam and the lower cross beam;

[0009] A horizontal lead screw, the horizontal lead screw is arranged parallel to the upper cross beam and the lower cross beam, one end of the horizontal lead screw is movably penetrated through the vertical plate by a spline or other force transmission mechanism, and the other end is movably penetrated through one of the reaction plates;

[0010] A dynamometer, the dynamometer is fixedly arranged at the end of the horizontal lead screw located outside the reaction plate;

[0011] A display, the display is connected to the force sensor of the dynamometer by electrical connection or wireless data transmission;

[0012] A commutation mechanism assembly, the commutation mechanism assembly is connected to the middle part of the horizontal lead screw and is used for driving the horizontal lead screw to move horizontally;

[0013] A rotating shaft, the lower end of the rotating shaft is connected to the commutation mechanism assembly, and the rotational force of the rotating shaft is converted into the horizontal transmission force of the horizontal lead screw through the commutation mechanism assembly. The upper end of the rotating shaft penetrates through the upper cross beam and is rotatably connected to the upper cross beam;

[0014] A handle, the handle is fixedly arranged at the top of the rotating shaft.

[0015] Further, the commutation mechanism assembly is a transmission gear, the transmission gear includes a first bevel gear and a second bevel gear, the first bevel gear is fixedly connected to the rotating shaft, a through hole is arranged in the middle of the second bevel gear, an internal thread is arranged in the through hole, and the internal thread is matched with the external thread on the horizontal lead screw; the horizontal lead screw penetrates through the through hole of the second bevel gear, and the first bevel gear meshes with the second bevel gear.

[0016] Further, the force value calibration device further includes a bearing, and the upper end of the rotating shaft is rotatably connected to the upper cross beam through the bearing.

[0017] Further, the force sensor in the dynamometer is a small-range micro force sensor, and its force receiving part can be equipped with a ball head pair to optimize and adaptively adjust the distribution of the bearing capacity, thereby reducing the azimuth error.

[0018] Further, the handle is driven in a manual, semi-automatic or automatic form, and is compared and tracked based on the target force value point feedback by the sensor of the measuring instrument and driven to load.

[0019] The advantages of the present utility model are as follows:

[0020] The utility model can directly measure the test force and directly read the force value through a supporting display, which can meet the force value calibration requirements of various small-range stiffness measuring instruments. It also has the advantages of simple structure, convenient operation, good general performance, small size, light weight and easy to carry. It overcomes the disadvantages of traditional use of weight testing, such as the force value weights are not easy to carry, the uncertainty introduced by the parallelism and coaxiality of each mechanical structure during the calibration of the measuring instrument, and the large operation difficulty. Moreover, the placement and force-bearing state of the device are similar to the actual state of the cup and bowl samples, effectively improving the convenience and accuracy of test calibration. In addition, the force value calibration device or its sensor of the utility model can be calibrated by a force standard machine or a force sensor calibration device.

Description of the Drawings

[0021] The following further describes the present utility model with reference to the accompanying drawings in conjunction with embodiments.

[0022] Figure 1 It is a schematic structural diagram of an existing cup body stiffness measuring instrument.

[0023] Figure 2 It is a schematic diagram of a force value calibration device for a small-range stiffness measuring instrument of the present utility model.

[0024] Figure 3 It is a schematic cross-sectional view of the cooperation between the lead screw and the vertical plate of a force value calibration device for a small-range stiffness measuring instrument of the present utility model.

[0025] Figure 4 It is a schematic diagram of the cooperation between the force value calibration device of the present utility model and an existing cup body stiffness measuring instrument.

Detailed Embodiments

[0026] The following will clearly and completely describe the technical solutions of the present utility model in conjunction with the accompanying drawings and specific embodiments. In the description of the present utility model, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present utility model. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0027] In the description of the present utility model, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", and "coupling" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0028] Please refer to Figure 2-3 as shown in the figure, a force value calibration device for a small-range stiffness tester of the present utility model includes:

[0029] A reaction frame 1, the reaction frame 1 includes two reaction plates 11, an upper cross beam 12, a lower cross beam 13 and a vertical plate 14. The two reaction plates 11 are vertically arranged and parallel to each other; the upper cross beam 12 and the lower cross beam 13 are respectively fixedly arranged at the upper and lower ends of the two reaction plates 11, the vertical plate 14 is arranged between the two reaction plates 11, and the upper and lower ends of the vertical plate 14 are respectively vertically arranged at the middle parts of the upper cross beam 12 and the lower cross beam 13;

[0030] A horizontal lead screw 2, the horizontal lead screw 2 is arranged parallel to the upper cross beam 12 and the lower cross beam 13. One end of the horizontal lead screw 2 is movably passed through the vertical plate 14 through a spline 21, and the other end is movably passed through one of the reaction plates 11;

[0031] A force measuring instrument 3, the force measuring instrument 3 is fixedly arranged at the end of the horizontal lead screw 2 located outside the reaction plate 11;

[0032] A display (not shown in the figure), the display is connected to the force sensor of the force measuring instrument 3 by means of electrical connection or wireless data transmission;

[0033] A reversing mechanism assembly 4, the reversing mechanism assembly 4 is connected to the middle part of the horizontal lead screw 2 and is used to drive the horizontal lead screw 2 to move horizontally;

[0034] A rotating shaft 5, the lower end of the rotating shaft 5 is connected to the reversing mechanism assembly 4. Through the reversing mechanism assembly 4, the rotational force of the rotating shaft 5 is converted into the horizontal transmission force of the horizontal lead screw 2. The upper end of the rotating shaft 5 passes through the upper cross beam 12 and is rotatably connected to the upper cross beam 12;

[0035] A handle 6, the handle 6 is fixedly arranged at the top of the rotating shaft 5.

[0036] In a specific implementation, a preferred embodiment is as follows: The commutation mechanism assembly 4 is a transmission gear, which includes a first bevel gear 41 and a second bevel gear 42. The first bevel gear 41 is fixedly connected to the rotating shaft 5. A perforation is provided in the middle of the second bevel gear 42, and an internal thread is provided in the perforation, which is matched with the external thread on the transverse lead screw 2. The transverse lead screw 2 is inserted into the perforation of the second bevel gear 42, and the first bevel gear 41 and the second bevel gear 42 are meshed with each other.

[0037] In a specific implementation, a preferred embodiment is as follows: The force value calibration device further includes a bearing 7, and the upper end of the rotating shaft 5 is rotationally connected to the upper cross beam 12 through the bearing 7.

[0038] In a specific implementation, a preferred embodiment is as follows: The force sensor in the force measuring instrument 3 is a small-range micro force sensor, and its force receiving part can be equipped with a ball head pair to optimize and adaptively adjust the distribution of the bearing capacity, thereby reducing the azimuth error.

[0039] In a specific implementation, a preferred embodiment is as follows: The handle 6 is driven in a manual, semi-automatic or automatic form, and based on the target force value point feedback by the sensor of the measuring instrument, it performs comparison tracking and drives the loading.

[0040] In another embodiment of the present invention, the using process of the present invention is as follows:

[0041] Refer to Figure 4 , the actual force-bearing state of this device is similar to the state of the actual cup and bowl samples. Place the force value calibration device on the fixed table 4' of the stiffness measuring instrument to be calibrated, orient the force measuring instrument 3 towards the test head 2', and press the top head 3' against the reaction plate 11 away from the force measuring instrument 3. By rotating the handle 6, through the transmission gear, slowly move the transverse lead screw 2 horizontally, so that the force measuring instrument 3 installed on one side of the transverse lead screw 2 moves horizontally towards the test head 2' and squeezes the test head 2'. At this time, the same force value is generated between the test head 2' and the force measuring instrument 3, and the specific force values are respectively displayed on the corresponding display screen 5' and the display. By comparing the magnitudes of the above two force values, the purpose of testing and calibrating the force value of the stiffness measuring instrument can be achieved (select 5 force value calibration points that are roughly evenly distributed within the range of 10% - 90% of the force value measurement range of the stiffness measuring instrument for test calibration).

[0042] In summary, the utility model can directly measure the test force and directly read the corresponding force value through the supporting display, which can meet the force value test and calibration requirements of various small-range stiffness measuring instruments. It also has the advantages of simple structure, convenient operation, good general performance, small size, light weight and easy to carry. It overcomes the disadvantages of traditional use of weights for testing, such as the weights being not easy to carry, the introduction of uncertainties in the parallelism and coaxiality of various mechanical structures during the calibration of the measuring instrument, and the large operation difficulty. Moreover, the placement and force-bearing state of the device are similar to the actual state of the cup and bowl samples, effectively improving the convenience and accuracy of the test and calibration. In addition, the force value calibration device or its sensor of the utility model can be calibrated by a force standard machine or a force sensor calibration device.

[0043] Although the specific embodiments of the utility model have been described above, those skilled in the art of this technology should understand that the specific embodiments we described are illustrative only and not used to limit the scope of the utility model. Equivalent modifications and changes made by those skilled in the art in accordance with the spirit of the utility model should be covered by the scope protected by the claims of the utility model.

Claims

1. A force calibration device for a small-range stiffness tester, characterized in that: include: A reaction frame, the reaction frame comprises two reaction plates, an upper cross beam, a lower cross beam and a vertical plate, the two reaction plates are vertically arranged and parallel to each other; the upper cross beam and the lower cross beam are respectively fixedly arranged at the upper and lower ends of the two reaction plates, the vertical plate is arranged between the two reaction plates, and the upper and lower ends of the vertical plate are respectively vertically arranged at the middle of the upper cross beam and the lower cross beam; A transverse screw rod, the transverse screw rod is arranged in parallel with the upper cross beam and the lower cross beam, one end of the transverse screw rod is movably inserted into the vertical plate through a spline or other force transmission mechanism, and the other end of the transverse screw rod is movably inserted into one of the reaction plates; A dynamometer, the dynamometer is fixedly arranged at the end of the transverse screw rod located outside the reaction plate; a display, wherein the display is connected to the force sensor of the dynamometer by electrical connection or wireless data transmission; a reversing mechanism assembly, the reversing mechanism assembly being connected to the middle portion of the transverse screw rod and being used for driving the transverse screw rod to move transversely; A rotating shaft, the lower end of which is connected to the reversing mechanism assembly, and the rotating force of the rotating shaft is converted into the lateral transmission force of the lateral screw rod through the reversing mechanism assembly, and the upper end of the rotating shaft passes through the upper beam and is rotatably connected to the upper beam; A handle is fixedly arranged on the top of the rotating shaft.

2. A force calibration device for a small-range stiffness tester as claimed in claim 1, characterized in that: The reversing mechanism assembly is a transmission gear, and the transmission gear includes a first bevel gear and a second bevel gear. The first bevel gear is fixedly connected to the rotating shaft, and a through hole is provided in the middle of the second bevel gear. An internal thread is provided in the through hole, and the internal thread matches the external thread on the transverse screw rod; the transverse screw rod is inserted into the through hole of the second bevel gear, and the first bevel gear and the second bevel gear are meshed with each other.

3. The force value calibration device of a small-range stiffness measuring instrument according to claim 1, characterized in that: The force calibration device also includes a bearing, and the upper end of the rotating shaft is rotatably connected to the upper crossbeam through the bearing.

4. The force value calibration device of a small-range stiffness measuring instrument according to claim 1, characterized in that: The force sensor in the dynamometer is a small-range miniature force sensor.

5. The force value calibration device of a small-range stiffness measuring instrument as claimed in claim 1, characterized in that: The handle is driven manually, semi-automatically or automatically.

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