Mechanical instrument convenient to calibrate

Abstract

The utility model relates to the field of mechanical measuring instruments, and discloses a mechanical instrument convenient to calibrate, which comprises a shell, a front panel, a force measuring rod and a sensor, the sensor is fixed above the inside of the shell, a strain swing arm is arranged at the center of the sensor, the root of the force measuring rod is fixed on the strain swing arm, and the tail end of the force measuring rod extends to the outer side of the top of the shell. The device is characterized in that a connecting block is arranged at one end of the outer side of the strain swing arm and connected with a preloading rod, the tail end of the preloading rod is in power connection with the output end of a transmission module, and the back of the shell is rotationally connected with a calibration wheel which is in power connection with the input end of the transmission module; compared with the prior art, the device has the advantages that when an instrument cannot return to zero, the transmission structure of the device applies external force to the sensor to enable the sensor to reach the resistance when the sensor returns to zero, a user only needs to rotate the calibration wheel to complete calibration operation, and the device is simple and convenient to use. A set of brake structure is arranged on the inner side of the calibration wheel, and after calibration is completed, the structure can keep the rotation position of the calibration wheel so as to maintain the deformation state of the sensor.

Description

Technical Field

[0001] The utility model relates to the field of mechanical measuring instruments, in particular to a mechanical instrument which is convenient for calibration. Background Art

[0002] A strain gauge force sensor is a sensor that measures the force applied to an object by measuring its deformation or strain. When an object is subjected to an external force, its shape and size will change slightly, and this change will cause a change in resistance. Currently, most handheld digital force gauges use a force measuring rod to apply an external force to the internal strain gauge force sensor to cause it to deform and measure the external force.

[0003] Since strain resistance force sensors need to deform to produce resistance changes, they are often shaped into a plate or block-shaped protrusion to withstand the deformation. When the force gauge is bumped or used incorrectly, this part of the sensor material is easily damaged and deformed, resulting in the inability to return to zero calibration during subsequent use. Utility Model Content

[0004] 1. Technical Problems Solved

[0005] The technical problem to be solved by the utility model is that it is difficult to return to zero and calibrate the sensor in the existing dynamometer after extreme use, and a mechanical instrument which is convenient for calibration is provided.

[0006] 2. Technical Solution

[0007] In order to solve the above technical problems, the technical solution provided by the utility model is: a mechanical instrument that is easy to calibrate, which includes a shell, a front panel, a force measuring rod and a sensor. The sensor is fixed on the upper part of the shell. A strain swing arm is provided in the center of the sensor. The root of the force measuring rod is fixed to the strain swing arm, and the end of the force measuring rod extends to the outside of the top of the shell.

[0008] A connecting block is provided at one end of the outer side of the strain swing arm, and the connecting block is connected to a preload rod. The end of the preload rod is dynamically connected to the output end of the transmission module. The back of the shell is rotatably connected to a calibration wheel, and the calibration wheel is dynamically connected to the input end of the transmission module.

[0009] Furthermore, a first clamping plate and a second clamping plate are arranged at intervals at the part where the preload rod is connected to the connecting block. The first clamping plate and the second clamping plate are arranged to bite each other on both sides of the connecting block. The preload rod is pushed and pulled by external force to deform the strain swing arm to offset its deformation when it cannot return to zero.

[0010] Furthermore, a screw rod is provided at the connection portion between the preload rod and the transmission module, and the screw rod extends into the interior of the transmission module.

[0011] Furthermore, a turbine and a worm are rotatably connected in the transmission module, the inner ring of the turbine is meshed with the lead screw, and the outer ring is meshed with the worm. One end of the worm is connected to a transmission shaft, which extends to the outer side of the back of the shell and is fixedly connected to the center of the calibration wheel. The user can easily calibrate the sensor through the above structure.

[0012] Furthermore, the calibration wheel is hollowly arranged toward one side of the outer shell, and a side wall is arranged around the calibration wheel. A mounting block is provided at the place where the calibration wheel is mounted on the outer shell, pistons are provided on both sides of the mounting block, and a friction plate is provided at the free end of the piston, and the friction plate is fitted with the side wall. A coil spring is provided on the other side of the friction plate fitted with the side wall and connected to the root of the piston, so that the internal strain swing arm maintains deformation by applying friction force to the calibration wheel.

[0013] 3. Beneficial Effects

[0014] The advantages of the utility model compared with the prior art are:

[0015] 1. This device has a transmission structure that can pre-deform the sensor. When the instrument cannot return to zero, an external force is applied to it to make it reach zero.

[0016] To reset the resistance to zero, the user only needs to turn the calibration wheel on the outside of the housing to complete the calibration operation, which is relatively easy to use.

[0017] 2. The calibration wheel is equipped with a brake locking structure on the inside, which can maintain the rotation position of the calibration wheel to maintain the deformation state of the sensor after the calibration is completed. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the structure of a mechanical instrument that is convenient for calibration.

[0019] Figure 2 It is a schematic diagram of the internal structure of a mechanical instrument that is easy to calibrate.

[0020] Figure 3 It is a structural schematic diagram of a transmission module of a mechanical instrument that is convenient for calibration.

[0021] Figure 4 The diagram is a structural diagram of a mechanical instrument calibration wheel for easy calibration.

[0022] As shown in the figure: 1. Housing, 2. Front panel, 3. Force measuring rod, 4. Calibration wheel, 5. Sensor, 6. Strain swing arm, 7. Connecting block, 8. Preload rod, 9. First clamping plate, 10. Second clamping plate, 11. Screw, 12. Transmission module, 13. Turbine, 14. Worm, 15. Transmission shaft, 16. Side wall, 17. Mounting block, 18. Coil spring, 19. Piston, 20. Friction plate. DETAILED DESCRIPTION

[0023] The utility model is further described in detail below in conjunction with the accompanying drawings.

[0024] Embodiment 1

[0025] Combined with Figure 1 , Attachment Figure 2 and attached Figure 3 A mechanical instrument that is easy to calibrate, it includes a shell 1, a front panel 2, a force measuring rod 3 and a sensor 5, the sensor 5 is fixed on the upper part of the shell 1, a strain swing arm 6 is provided in the center of the sensor 5, the root of the force measuring rod 3 is fixed to the strain swing arm 6, and the end of the force measuring rod 3 extends to the outside of the top of the shell 1.

[0026] A connecting block 7 is provided at one end of the outer side of the strain swing arm 6, and the connecting block 7 is connected to a preload rod 8. The end of the preload rod 8 is poweredly connected to the output end of the transmission module 12. The back of the housing 1 is rotatably connected to the calibration wheel 4, and the calibration wheel 4 is poweredly connected to the input end of the transmission module 12.

[0027] The first clamping plate 9 and the second clamping plate 10 are arranged at intervals at the portion where the preload rod 8 is connected to the connection block 7 . The first clamping plate 9 and the second clamping plate 10 are arranged at both sides of the connection block 7 to be engaged with each other.

[0028] The strain swing arm 6 can be pushed and pulled to deform by controlling the preload rod 8 to translate along its axial direction. The zero resistance of the strain swing arm 6 can be adjusted by applying a load to the strain swing arm 6 in advance to change its resistance, thereby achieving calibration.

[0029] A screw 11 is provided at the connection part between the preload rod 8 and the transmission module 12, and the screw 11 extends into the transmission module 12. A turbine 13 and a worm 14 are rotatably connected in the transmission module 12 respectively. The inner ring of the turbine 13 is meshed with the screw 11, and the outer ring is meshed with the worm 14. A transmission shaft 15 is connected to one end of the worm 14, and the transmission shaft 15 extends to the outer side of the back of the housing 1 and is fixedly connected to the center of the calibration wheel 4.

[0030] The user only needs to rotate the calibration wheel 4 on the back of the housing 1 to drive the preload rod 8 to translate along its axial direction to apply load to the strain swing arm 6 for calibration.

[0031] Embodiment 2

[0032] Combined with Figure 4The calibration wheel 4 is hollowly arranged on one side facing the housing 1, and a side wall 16 is arranged around the calibration wheel 4. A mounting block 17 is arranged at the housing 1 where the calibration wheel 4 is mounted, and pistons 19 are arranged on both sides of the mounting block 17. A friction plate 20 is arranged at the free end of the piston 19, and the friction plate 20 is arranged in contact with the side wall 16. A coil spring 18 is arranged on the other side of the friction plate 20 in contact with the side wall 16 and connected to the root of the piston 19.

[0033] Since the strain swing arm 6 is elastic, a certain force needs to be applied to it to maintain its deformation when it is preloaded. Since the calibration wheel 4 and the transmission module 12 themselves have a certain reduction ratio, the calibration wheel 4 can maintain the deformation of the strain swing arm 6 by applying a small friction force through the above structure.

[0034] The above description of the utility model and its implementation methods is not restrictive. The drawings show only one implementation method of the utility model, and the actual structure is not limited thereto. In short, if ordinary technicians in this field are inspired by it and design structural methods and embodiments similar to the technical solution without creativity without departing from the purpose of the invention of the utility model, they should all fall within the protection scope of the utility model.

Claims

1. A mechanical instrument convenient for calibration, comprising a housing (1), a front panel (2), a force measuring rod (3) and a sensor (5), wherein the sensor (5) is fixed to the upper part of the housing (1), a strain swing arm (6) is provided in the center of the sensor (5), the root of the force measuring rod (3) is fixed to the strain swing arm (6), and the end of the force measuring rod (3) extends to the outer side of the top of the housing (1), characterized in that: A connecting block (7) is provided at one end of the outer side of the strain swing arm (6), and a preload rod (8) is connected to the connecting block (7). The end of the preload rod (8) is dynamically connected to an output end of a transmission module (12). The back of the housing (1) is rotatably connected to a calibration wheel (4), and the calibration wheel (4) is dynamically connected to an input end of the transmission module (12).

2. A mechanical instrument for convenient calibration according to claim 1, characterized in that: A first clamping plate (9) and a second clamping plate (10) are arranged at intervals at the portion where the preload rod (8) is connected to the connection block (7); the first clamping plate (9) and the second clamping plate (10) are arranged to be engaged with each other on both sides of the connection block (7).

3. A mechanical instrument for convenient calibration according to claim 1, characterized in that: A screw rod (11) is provided at the connection portion between the preload rod (8) and the transmission module (12), and the screw rod (11) extends into the interior of the transmission module (12).

4. A mechanical instrument for convenient calibration according to claim 3, characterized in that: A turbine (13) and a worm (14) are rotatably connected in the transmission module (12); the inner ring of the turbine (13) is meshed with the lead screw (11), and the outer ring is meshed with the worm (14); one end of the worm (14) is connected with a transmission shaft (15); the transmission shaft (15) extends to the outer side of the back of the housing (1) and is fixedly connected to the center of the calibration wheel (4).

5. A mechanical instrument for convenient calibration according to claim 1, characterized in that: The calibration wheel (4) is hollowly arranged on one side facing the housing (1); a side wall (16) is arranged around the calibration wheel (4); a mounting block (17) is arranged at the housing (1) where the calibration wheel (4) is mounted; pistons (19) are arranged on both sides of the mounting block (17); a friction plate (20) is arranged at the free end of the piston (19); the friction plate (20) is arranged in contact with the side wall (16); a coil spring (18) is arranged on the other side of the friction plate (20) in contact with the side wall (16) and is connected to the root of the piston (19).

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