An anti-shear dynamic weighing sensor

Abstract

An anti-shear dynamic weighing sensor includes a sensor body, which is an integral structure. The sensor body includes a central shaft body and at least two elastic strain bodies connected to the central shaft body, and the at least two elastic strain bodies are symmetrically arranged along the axis of the central shaft body. It also includes a base connected to the central shaft body, and the base is connected to a fixed surface during installation. It further includes force-receiving protrusions respectively installed on the elastic strain bodies, and a first strain gauge and a second strain gauge are respectively installed on the two elastic strain bodies. Structures such as a limiting device and a pull rod are omitted, reducing the installation and maintenance costs, eliminating the influence of shear force during dynamic weighing, and improving the accuracy of detection data.

Description

Technical Field

[0001] The present invention relates to the technical field of weighing sensor devices, and in particular to a shear-resistant dynamic weighing sensor. Background Art

[0002] Sensor technology is widely used in all walks of life, and the size of its error directly affects the performance and measurement accuracy of the measurement and control system. Modern measurement and control systems have put forward higher requirements for the accuracy, stability and working conditions of sensors. Strain-type weighing sensors are the core components of electronic weighing scales and play an important role in many links such as production, sales, quality control, and product grading in the industrial and agricultural fields. However, the strain-sensitive areas of existing strain-type sensors are generally relatively thin. Mainly to obtain a larger deformation amount, the strain gauges adhered to them have a larger deformation amount and a higher output sensitivity. Therefore, when in use, the sensor usually needs to be equipped with a limiting device or a pull rod during installation and use. In order to reduce the damage of the deformation area of the sensor when it is subjected to a shear force in a direction different from the direction of the positive pressure, but there are the following problems:

[0003] 1. Although the method of adding a limiting device or a pull rod can cope with the influence of the shear force on the deformation area, these structures have wear or loosening of fasteners after long-term use, making the sensor prone to damage when subjected to a large shear force after long-term use, and professional personnel need to perform regular calibration and correction, increasing the installation and maintenance costs during the use of the sensor.

[0004] 2. The method of adding a limiting device or a pull rod will also increase the production cost of the sensor, and at the same time increase the volume of the sensor, making it inconvenient to install.

[0005] 3. At the same time, when using a limiting device or a pull rod, after it becomes loose, the shear force on the sensor during dynamic weighing will affect the weighing result, reducing the accuracy of the measured value and having an adverse impact on the user. Summary of the Invention

[0006] In view of the above situation, in order to overcome the defects of the prior art, the purpose of the present invention is to provide a shear-resistant dynamic weighing sensor, which reduces the installation and maintenance costs and improves the accuracy of the detection data by eliminating structures such as limiting devices and pull rods.

[0007] The solution is a shear-resistant dynamic weighing sensor, including a sensor body. The sensor body is an integral mechanism. The sensor body includes a central shaft body and at least two elastic strain bodies connected to the central shaft body, and the at least two elastic strain bodies are symmetrically arranged along the axis of the central shaft body. It also includes a base connected to the central shaft body, and the base is connected to a fixed surface during installation. It also includes force-acting protrusions respectively installed on the elastic strain bodies, and a first strain gauge and a second strain gauge are respectively installed on the two elastic strain bodies.

[0008] Furthermore, in the present invention, the number of the at least two elastic strain bodies is an even number, and the elastic strain bodies are arranged in pairs.

[0009] Furthermore, in the present invention, the number of the force-receiving protrusions is the same as the number of the elastic strain bodies, and the plurality of force-receiving protrusions are respectively disposed at the ends of the corresponding elastic strain bodies on the side away from the central axis.

[0010] Furthermore, in the present invention, the elastic strain body is in a plate-like structure, and the first strain gauge and the second strain gauge are mounted on the elastic strain body in pairs, and the first strain gauge and the second strain gauge are symmetrically arranged along the axis of the central axis body.

[0011] Furthermore, in the present invention, the force-receiving protrusions are arranged along the edge of the plate-like elastic strain body.

[0012] Furthermore, in the present invention, it further includes a fixing plate located above the elastic strain body, and the plurality of force-receiving protrusions are fixedly connected to the fixing plate.

[0013] Advantages of the present invention: By adopting a weighing sensor with a novel structure, the limiting device and the pull rod and other structures used to cope with shear force in the prior art are cancelled, the production cost and the volume of the sensor are reduced, and at the same time, the installation and regular maintenance and correction costs are reduced. The shear force generated during dynamic weighing is eliminated, the accuracy of the dynamic weighing detection data is improved, the user experience is enhanced, and at the same time, the effect of coping with shear force is improved, and the service life of the sensor is increased. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic structural view of the whole front of the present invention.

[0015] Figure 2 It is a schematic structural view of the axonometric of the circular structure of the whole sensor of the present invention.

[0016] Figure 3 It is a schematic structural view of the circuit bridge of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0017] The following further describes in detail the specific embodiments of the present invention with reference to the accompanying drawings.

[0018] By Figure 1Provided is a shear-resistant dynamic weighing sensor, including a sensor body, the sensor body being an integral structure, the sensor body including a central shaft body 5 and at least two elastic strain bodies 6 connected to the central shaft body 5, and the at least two elastic strain bodies 6 being symmetrically arranged along the axis of the central shaft body 5. A first strain gauge 4 and a second strain gauge 7 are respectively installed on the two elastic strain bodies 6. The first strain gauge 4 and the second strain gauge 7 will change following the deformation of the elastic strain bodies 6. When subjected to a shear force from the first strain gauge 4 towards the second strain gauge 7, the grid wires of the first strain gauge 4 and the second strain gauge 7 become thicker and shorter (this change is a minute change, and the voltage change caused by the resistance change generated by this change will be amplified by voltage, enabling it to become a voltage signal that can be detected and recognized), and the resistance becomes smaller.When the grid wires of the first strain gauge 4 and the second strain gauge 7 are stretched under a positive pressure, and the grid wires become thinner and longer, the resistance increases. Moreover, the change amounts of the first strain gauge 4 and the second strain gauge 7 vary linearly with the magnitude of the force causing the deformation. It also includes a base 1 connected to the central shaft body 5, and during installation, the base 1 is connected to the fixed surface. It further includes a force-receiving protrusion 3 installed on the elastic strain body 6, and a fixing plate 2 located above the elastic strain body 6. And a plurality of the force-receiving protrusions 3 are all fixedly connected to the fixing plate 2. When in use, the sensor is installed at the position to be weighed through the base 1. Two of the force-receiving protrusions 3 are respectively placed at the ends of the corresponding elastic strain bodies 6 away from the axis of the central shaft body 5, and a plurality of the force-receiving protrusions 3 are all fixedly connected to the fixing plate 2. When in use, the fixing plate 2 is fixedly connected between the load-bearing plate surface, so as to fix the spacing of a plurality of force-receiving protrusions 3. When the load-bearing plate surface sways horizontally, it drives a plurality of force-receiving protrusions 3 to move back and forth. However, since the detection data is based on the deformation of the elastic strain body 6, and the number of the at least two elastic strain bodies 6 is an even number, and the elastic strain bodies 6 are arranged in pairs, thus enabling the first strain gauges 4 and the second strain gauges 7 in pairs to form a bridge circuit. Furthermore, the movement of the force-receiving protrusion 3 will drive the connected elastic strain body 6 to produce different deformation effects. That is, when the force-receiving protrusion 3 is subjected to a shear force in the left-to-right direction, the left elastic strain body 6 is squeezed, and the right elastic strain body 6 is stretched. And the number of the first strain gauges 4 and the second strain gauges 7 installed on the elastic strain body 6 decreases simultaneously, thereby offsetting the influence of the shear force on the detection data. While the existing weighing devices adopt adding a limiting device or a pull rod to prevent its movement in the direction of the shear force. This device realizes eliminating the influence of the shear force on the weighing data without using a limiting device or a pull rod by changing its installation method and circuit, does not require regular correction and maintenance, reduces the production cost of the device, reduces the installation and subsequent maintenance costs of the weighing device, reduces the volume of the sensor, and eliminates the influence of the shear force on the detection data, increasing the accuracy of the detection data. The sensor with this structure has a high-strength elastic strain body 6, and the shear resistance safety factor is greater than 200%, and at the same time, it has high strength, small deformation amount, small creep, and fast response, and is suitable for dynamic weighing. And the design of this device can adapt to various specifications of sensors. Taking the actual measurement of a 15T sensor as an example, the sensor sensitivity is 1mV / V, the comprehensive error is 0.3(%FS), the safety overload range is 150(%FS), the ultimate overload range is 300(%FS), and the shear force resistance range is 200(%FS). The shape of the elastic strain body 6 in this device can adopt any one of a square, a circle, a strip, or a polygon, with strong adaptability and diverse selection.

[0019] Other specific implementation schemes of the present invention, according to the attached Figure 2It can be obtained that the elastic strain body is in a plate-like structure, and the first strain gauge 4 and the second strain gauge 7 are installed in pairs on the elastic strain body 6. The first strain gauge 4 and the second strain gauge 7 are symmetrically arranged along the axis of the central shaft body. The force-bearing protrusion 3 is arranged along the edge of the plate-like elastic strain body. Setting the elastic strain body 6 as a plate-like structure, and at the same time arranging the force-bearing protrusion 3 along the edge of the plate-like elastic strain body and making it integral with the elastic strain body 6 can further increase the stability. Compared with the strip-shaped elastic strain body 6, it has higher strength, increases its force-bearing range, can meet the weighing of large weights, and can also cope with large shear forces, increasing the service life of the sensor. Moreover, the plate-like structure area of the elastic strain body 6 can be one of a circle, a square or a polygon, which can be adjusted according to production requirements. It only needs to ensure that the paired first strain gauge 4 and second strain gauge 7 are symmetrically arranged along the axis of the central shaft body to meet the cancellation of shear force during weighing. And multiple groups of paired first strain gauges 4 and second strain gauges 7 can be set, which can be adjusted according to production requirements.

[0020] When the circuit bridge of the present invention is implemented, according to the attached Figure 3 It can be obtained that it further includes a first strain gauge 4, a second strain gauge 7, a third resistor R3 and a fourth resistor R4, and they are connected in series in the order of the first strain gauge 4, the fourth resistor R4, the second strain gauge 7 and the third resistor R3. There is a positive voltage terminal VCC connected between the second strain gauge 7 and the third resistor R3, a negative voltage terminal VSS connected between the first strain gauge 4 and the fourth resistor R4, a first voltmeter is connected between the second strain gauge 7 and the fourth resistor R4, and a second voltmeter is connected between the first strain gauge 4 and the third resistor R3. As shown by the bridge in the attached drawing, where the first strain gauge 4 is resistor R1, the second strain gauge 7 is resistor R2, and the detection data of the first voltmeter and the second voltmeter are G- and G+ respectively. When R1 decreases, the G+ voltage decreases; when R2 increases, the G- voltage decreases. Therefore, when the shear forces G+ and G- act simultaneously, they both decrease, and the voltage difference between G+ and G- remains unchanged. When a positive pressure is applied, R1 and R2 increase simultaneously, G+ becomes larger, G- becomes smaller, and the voltage difference between G+ and G- is the pressure value (weighing value) output by the sensor. Through the cooperation of the above bridge and the above device, it can realize the influence of shear force on the weighing sensor during the detection of dynamic data and improve the accuracy of the detection data.

[0021] The beneficial effects of the present invention: By using a weighing sensor with a novel structure, the existing limiting devices and tie rods and other structures used to cope with shear forces are cancelled, reducing the production cost and the volume of the sensor, while also reducing the costs of installation and regular maintenance and correction. It eliminates the action of shear force generated during dynamic weighing, improves the accuracy of dynamic weighing detection data, enhances the user experience, and at the same time improves the effect of coping with shear force and increases the service life of the sensor.

[0022] The embodiments described above do not limit the scope of the present invention. Without departing from the design concept of the present invention, various modifications and improvements made by those skilled in the art to the technical solutions of the present invention shall fall within the protection scope determined by the claims of the present invention.

Claims

1. An anti-shear dynamic weighing sensor, comprising a sensor body, characterized in that, The sensor body is an integral structure; The sensor body includes a central shaft body (5) and at least two elastic strain bodies (6) connected to the central shaft body (5), and the at least two elastic strain bodies (6) are symmetrically arranged along the axis of the central shaft body (5); It further includes a base (1) connected to the central shaft body (5), and the base (1) is connected to the fixed surface during installation; It further includes a force-bearing protrusion (3) installed on the elastic strain body (6); Among them, a first strain gauge (4) or a second strain gauge (7) is respectively installed on the at least two elastic strain bodies (6); The first strain gauge (4) and the second strain gauge (7) are installed in pairs on the elastic strain body (6), the paired first strain gauge (4) and second strain gauge (7) are symmetrically arranged along the axis of the central shaft body (5), and the paired first strain gauge (4) and second strain gauge (7) form a bridge circuit; It further includes a fixing plate (2) located above the elastic strain body (6), and the force-bearing protrusions (3) are all fixedly connected to the fixing plate (2).

2. The anti-shear dynamic weighing sensor according to claim 1, characterized in that, The number of the at least two elastic strain bodies (6) is an even number, and the elastic strain bodies are arranged in pairs.

3. The anti-shear dynamic weighing sensor according to claim 2, characterized in that, The number of the force-bearing protrusions (3) is the same as the number of the elastic strain bodies (6), and the multiple force-bearing protrusions (3) are respectively placed at the ends of the corresponding elastic strain bodies (6) on the side away from the central axis.

4. The anti-shear dynamic weighing sensor according to claim 1, characterized in that, The elastic strain body (6) is a plate-like structure.

5. The anti-shear dynamic weighing sensor according to claim 1, characterized in that, The force-bearing protrusion (3) is arranged along the edge of the plate-like elastic strain body (6).

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