Integrated strain gauge

Abstract

The invention is suitable for the technical field of strain gauges, and provides an integrated strain gauge. Comprising a substrate and strain unit groups. The outline shape of the base is rectangular; the strain unit groups are symmetrically distributed on the substrate and cured on the surface of the substrate. Moreover, the strain unit group can be used for detecting forces in three different directions and moments in three different directions. Therefore, the strain unit group is solidified on the substrate, so that the strain unit group can be arranged at one time by pasting the strain unit group on the elastic arm, and the convenience and the efficiency of pasting the strain gauge are improved. Moreover, the strain unit groups are symmetrically distributed on the substrate, so that the detection performance in the symmetrical direction can be kept consistent, and the detection performance is stable. Moreover, the strain unit group has the function of detecting forces in three different directions and moments in three different directions, the detection functions are diversified, the detection sensitivity is good, and different detection requirements can be well met.

Description

Technical Field

[0001] The invention belongs to the technical field of strain gauges, and in particular relates to an integrated strain gauge. Background Art

[0002] In force sensors, strain gauges are usually attached to strain beams. When the strain beam is strained under force, the resistance of the strain gauge changes with the deformation of the strain beam. By analyzing the change in resistance, the strain of the strain beam can be measured, and the changes in the force and torque of the strain beam can be sensed.

[0003] In the related art, the strain gauge is a separate part, which is fixed on the strain beam by pasting one by one. Even if multiple strain gauges need to be pasted in the same area of ​​the strain beam, they are placed one by one. This setting method has the problems of low pasting efficiency and great difficulty in maintaining consistency. Summary of the invention

[0004] In view of this, the present invention provides an integrated strain gauge to solve the problems of low installation efficiency and high consistency difficulty of each strain gauge.

[0005] To solve the above problems, the technical solution of the present invention is achieved as follows:

[0006] An integrated strain gauge comprises: a substrate, the contour shape of which is set to be a rectangle; a strain unit group, which is symmetrically distributed on the substrate and solidified on the surface of the substrate; wherein the strain unit group can be used to detect forces in three different directions and moments in three different directions.

[0007] An integrated strain gauge provided by an embodiment of the present invention includes a substrate and a strain unit group. The contour shape of the substrate is set to be rectangular; the strain unit group is symmetrically distributed on the substrate and solidified on the surface of the substrate. In addition, the set strain unit group can be used to detect forces in three different directions and moments in three different directions. In this way, by solidifying the strain unit group on the substrate, when the operation of pasting it on the elastic arm is performed, only one pasting is required to complete the arrangement of the strain unit group at one time, and there is no need to paste each part constituting the strain unit group one by one, thereby improving the convenience and efficiency of strain gauge pasting. In addition, the strain unit group is symmetrically distributed on the substrate, so that the detection performance in the symmetrical direction can be better maintained consistent, and the detection performance is stable. In addition, the strain unit group has the detection function that can be used for forces in three different directions and moments in three different directions, has diverse detection functions, good detection sensitivity, and can better meet different detection needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1is a schematic structural diagram of an integrated strain gauge provided in an embodiment of the present invention;

[0009] Figure 2 It is a schematic diagram of the integrated strain gauge used for six detection channels;

[0010] Figure 3 This is the principle diagram of the Wheatstone bridge;

[0011] Figure 4 is a schematic diagram of the three different types of Wheatstone bridges;

[0012] Figure 5 is a schematic structural diagram of a second integrated strain gauge provided in an embodiment of the present invention;

[0013] Figure 6 is a schematic structural diagram of a third integrated strain gauge provided in an embodiment of the present invention;

[0014] Figure 7 is a schematic structural diagram of a fourth integrated strain gauge provided in an embodiment of the present invention;

[0015] Figure 8 is a schematic structural diagram of a fifth integrated strain gauge provided by an embodiment of the present invention;

[0016] Fig. 9 is a schematic structural diagram of a sixth integrated strain gauge provided by an embodiment of the present invention;

[0017] Fig.10 is a schematic structural diagram of a seventh integrated strain gauge provided by an embodiment of the present invention;

[0018] Fig.11 is a schematic structural diagram of an eighth integrated strain gauge provided by an embodiment of the present invention;

[0019] Fig.12 4 is a schematic diagram of the structure of the tenth integrated strain gauge provided in an embodiment of the present invention.

[0020] Description of reference numerals:

[0021] 10. Integrated strain gauge; 1. Base; Q. First symmetry axis; W. Second symmetry axis; 2. Strain unit group; 20. Strain unit; 201. Sensitive grid; 202. Pad; 203. Vertical strain unit; 204. Oblique strain unit; 21. First strain unit; 22. Second strain unit; 23. Inclined strain unit; P. Symmetry axis. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0023] The various specific technical features described in the specific embodiments can be combined in any suitable manner without contradiction, for example, different embodiments and technical solutions can be formed by combining different specific technical features. In order to avoid unnecessary repetition, various possible combinations of the specific technical features in the present invention will not be described separately.

[0024] In the following description, the terms "first\second\..." are only used to distinguish different objects, and do not mean that the objects have the same or related points. It should be understood that the directions "above", "below", "outside" and "inside" are all directions in normal use, and the directions "left" and "right" refer to the left and right directions shown in the corresponding schematic diagrams, which may or may not be the left and right directions in normal use.

[0025] It should be noted that the terms "comprises", "includes" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element. "Multiple" means greater than or equal to two.

[0026] like Figure 1As shown, an integrated strain gauge 10 provided in an embodiment of the present invention is used to be arranged on each elastic arm of a force sensor. Specifically, a strain gauge is attached to the detection position of each elastic arm, so that the force or torque acting on the elastic arm can be detected through the strain gauge. The working principle of the force sensor is: when an external force or torque acts on the sensor, the elastic arm will undergo a slight deformation (such as a change in length and cross-sectional area), and this deformation will be transmitted to the strain gauge attached to the elastic arm. The resistance value of the strain gauge changes with the generation of strain, and this resistance change is converted into a voltage or current signal through a specific circuit. A bridge circuit is constructed inside the sensor, and multiple strain gauges are connected together in a specific way to form a Wheatstone bridge. When the resistance value of the strain gauge changes, the equilibrium state of the bridge circuit will be broken, thereby generating an output signal proportional to the mechanical quantity. After the signal is amplified, filtered and digitized by the signal processing circuit, it can be read and analyzed by a terminal device such as a computer, and the corresponding force condition can be obtained.

[0027] Strain gauges are usually made of metal or semiconductor materials, with high sensitivity and good elastic properties, and can effectively sense the effects of external forces and torques. The elastic arms are usually set with three or four or multiples of four, and a strain gauge is set on each elastic arm. The number of strain gauges can be set according to the specific detection requirements to be achieved. For example, on a force sensor with three or four elastic arms, each elastic arm has at least one strain gauge, which can achieve detection of six measurement channels. Specifically, if Figure 2 As shown in the figure, according to the Cartesian coordinate system, the six measurement channels are three force components (Fx, Fy, Fz) and three torque components (Mx, My, Mz). The three force components correspond to the forces on the X, Y, and Z axes, respectively. The forces on each axis will cause the strain gauge in the corresponding direction to deform, resulting in a change in resistance. The three torque components correspond to the torque on the X, Y, and Z axes, respectively. The torque will also cause the strain gauge in a specific direction to deform, thereby causing a change in resistance.

[0028] The signal of each measurement channel is detected by the strain gauges attached to the elastic arm. These strain gauges can sense the resistance change caused by the tiny deformation and then convert it into an electrical signal output. The magnitude and direction of the applied force and torque can be determined by the signals of these channels combined with the corresponding mathematical model calculation.

[0029] The "six measurement channels" mentioned above correspond to the six force components of the sensor in three-dimensional space. In this way, the strain gauges on different elastic arms are combined according to the detection requirements to form a Wheatstone bridge to detect the change in resistance, and the magnitude of the applied force and torque and the direction of the force are finally determined by obtaining the detection signals on different channels.

[0030] like Figure 3 As shown in the figure, the Wheatstone bridge is a circuit device composed of four resistors, which is used to measure the resistance of one of the resistors, provided that the resistance of the other three resistors is known. The basic principle is to determine the value of the unknown resistor by comparing the voltage difference between two circuit branches. When the bridge is in a balanced state, the voltage difference between the two relative joints is zero. At this time, the resistance of the unknown resistor can be inferred from the known resistance values ​​of the three resistors. In the Wheatstone bridge, each resistor (or strain gauge) is usually called a bridge arm, so there are four bridge arms.

[0031] In specific applications, the main types of Wheatstone bridges include full bridge, half bridge and quarter bridge. Figure 4 As shown in a, in the full-bridge configuration, strain gauges are used in all four bridge arms, and each strain gauge produces the same magnitude of resistance change for the same strain, but the change direction is opposite. Figure 4 As shown in Figure 2, in the half-bridge configuration, only two bridge arms use strain gauges, and the other two are fixed resistors. Figure 4 As shown in Figure 3, in the 1 / 4 bridge configuration, only one bridge arm uses a strain gauge, and the other three are fixed resistors. Among the three different types of bridges, the principles of strain detection of full bridge, half bridge and 1 / 4 bridge are different in their sensitivity to strain and measurement accuracy. The full bridge configuration provides the highest sensitivity and accuracy, while the 1 / 4 bridge configuration provides the lowest sensitivity and accuracy. Therefore, the type of bridge to be combined can be selected according to the actual use requirements to meet different detection requirements, and the setting flexibility is good.

[0032] Strain gauges are usually fixed on elastic arms by pasting, and in order to achieve multi-channel detection, multiple strain gauges need to be pasted in the same pasting area of ​​each elastic arm. Pasting each strain gauge on the elastic arm one by one has many pasting steps, low efficiency, and difficulty in ensuring the consistency of pasting quality of each strain gauge. Therefore, an integrated strain gauge 10 is provided in an embodiment of the present invention to reduce the steps required for pasting multiple strain gauges on the elastic arm, improve the pasting efficiency, and better ensure the consistency of pasting quality of each strain gauge.

[0033] like Figure 1As shown, the integrated strain gauge 10 provided in an embodiment of the present invention includes a substrate 1 and a strain unit group 2. The substrate 1 is a thin sheet structure, and the contour shape of the substrate 1 is set to a rectangle. The contour shape of the area of ​​the elastic arm used to paste the strain gauge is usually also set to a rectangle, so that the shapes of the substrate 1 and the patch area remain basically matched, thereby facilitating pasting and maintaining the accuracy of the pasting position, so that the deformation of the elastic arm can be detected more sensitively. The strain unit group 2 is solidified on the substrate 1 and can undergo elastic deformation following the substrate 1. Specifically, the strain unit group 2 is symmetrically distributed on the substrate 1, so that the detection performance in the symmetrical direction can be better maintained consistent, and the detection performance is stable. Generally, the strain unit group 2 is composed of a plurality of strain units with the same structure and shape. Therefore, the strain unit group 2 is symmetrically distributed on the substrate 1, which means that the overall shape composed of a plurality of strain units is symmetrically distributed on the substrate 1 with the same symmetry axis.

[0034] Specifically, in an embodiment of the present invention, the strain unit group 2 can be used to detect forces in three different directions and moments in three different directions as needed. In this way, the integrated strain gauge 10 is provided on each elastic arm, and can be combined by selecting corresponding strain units to achieve a multi-channel detection function. The above "can be used to detect forces in three different directions and moments in three different directions" means that the structure of the strain unit group 2 can be set accordingly according to the detection needs (such as increasing the number of strain units), so as to meet the performance of being able to detect forces in three different directions and moments in three different directions. Not every strain unit can detect six channels, and in the actual detection process, it is not necessary to detect six channels at the same time. That is, the integrated strain gauge 10 can have the performance of being able to detect forces in three different directions and moments in three different directions by adopting a structural design that integrates the strain unit group 2 with the substrate 1. The detection performance is comprehensive, the detection function is improved, and the practicality is good.

[0035] In an embodiment of the present invention, the strain unit group 2 is fixed on the same substrate 1. In this way, the installation of each strain unit constituting the strain unit group 2 can be achieved by fixing the substrate 1 on the elastic arm once. That is, multiple strain units can be pasted at one time without pasting them one by one, which saves the steps of pasting the strain gauges, thereby improving the pasting efficiency of the strain gauges. In addition, the position and firmness of each strain unit fixed on the substrate 1 have been completed in advance, so when pasting and fixing on the elastic arm, it is only necessary to ensure the accuracy of the pasting position of the substrate 1 to achieve accurate pasting of each strain unit. At the same time, the consistency of pasting of each strain unit can be ensured, so that each strain unit can detect the deformation of the elastic arm in time, which improves the sensitivity and accuracy of the detection of each strain unit pasted on the elastic arm.

[0036] An integrated strain gauge 10 provided in an embodiment of the present invention includes a substrate 1 and a strain unit group 2. The outline shape of the substrate 1 is set to be rectangular; the strain unit group 2 is symmetrically distributed on the substrate 1 and solidified on the surface of the substrate 1. In addition, the set strain unit group 2 can be used to detect forces in three different directions and moments in three different directions. In this way, the strain unit group 2 is solidified on the same substrate 1, so that when the operation of pasting it on the elastic arm is performed, only one pasting is required to complete the arrangement of all strain units in the strain unit group 2 at one time, and there is no need to paste each strain unit constituting the strain unit group 2 one by one, thereby improving the convenience and efficiency of strain gauge pasting. Moreover, the strain unit group 2 is symmetrically distributed on the substrate 1, so that the detection performance in the symmetrical direction can be better maintained consistent, and the detection performance is stable. In addition, the strain unit group 2 has the detection function that can be used for forces in three different directions and moments in three different directions, has diverse detection functions, good detection sensitivity, and can better meet different detection needs.

[0037] In some embodiments, the substrate 1 material is generally a thin sheet made of polyimide material, which has good insulation properties and the ability to transmit strain. In some special applications, ceramic materials are also used as the substrate 1 to provide higher stability and high temperature resistance. In some cases, metal materials can also be used as the substrate 1, especially in applications that require high strength and durability. Therefore, the material type of the substrate 1 can be selected according to the specific application environment and requirements of the strain gauge.

[0038] In some embodiments, Figure 1 As shown, the substrate 1 at least includes a first symmetry axis Q located in a first direction and a second symmetry axis W located in a second direction, and the first direction and the second direction are perpendicular; wherein the strain unit group 2 includes at least four strain units 20, each strain unit 20 is symmetrically distributed on the substrate 1 at least relative to the second symmetry axis W, and each strain unit 20 includes a sensitive gate and a pad connecting both ends of the sensitive gate. Specifically, the outline shape of the substrate 1 is a rectangle, which can be specifically set according to the regional shape of the patch required. In the embodiment of the present invention, the shape of the substrate 1 is set to have at least two symmetry axes, so that the regional shape of the patch can be set to one of a square or a rectangle according to the actual required shape of the patch.

[0039] The strain unit group 2 includes at least four strain units 20, so that at least four strain units 20 are arranged on the same substrate 1, and each strain unit 20 is independent of each other and is used to realize the required detection function respectively. In this way, at least four strain units 20 can be pasted at the same time by pasting once, which saves the pasting steps of strain gauges, thereby improving the pasting efficiency of strain gauges. In addition, the position and firmness of each strain unit 20 fixed on the substrate 1 have been completed in advance, so when pasting and fixing on the elastic arm, it is only necessary to ensure the accuracy of the pasting position of the substrate 1 to achieve accurate pasting of each strain unit 20, and at the same time, it can also ensure the consistency of pasting of each strain unit 20, so that each strain unit 20 can detect the deformation of the elastic arm in time, and improve the sensitivity and accuracy of detection of each strain unit 20 pasted on the elastic arm.

[0040] Specifically, the strain unit group 2 is configured to include at least four strain units 20, and each strain unit 20 is symmetrically distributed on the substrate 1 at least relative to the second symmetry axis W. "Each strain unit 20 is symmetrically distributed on the substrate 1 at least relative to the second symmetry axis W" means that the shape formed by the combination of each strain unit 20 on the substrate 1 is symmetrically distributed relative to the second symmetry axis W of the substrate 1.

[0041] refer to Figure 5 , the "first direction" mentioned above is as follows Figure 5 The horizontal direction shown in the paper, and the “second direction” is as follows Figure 5 The vertical direction shown in the middle paper.

[0042] Specifically, Figure 1 As shown, each strain unit 20 includes a sensitive grid 201 and a pad 202 connecting the two ends of the sensitive grid 201. The sensitive grid 201 is usually made of a thin wire made of a material such as constantan, nickel-chromium alloy, etc., and then wound in a grid or spiral shape so that it can effectively sense deformation when subjected to force. The two ends of the sensitive grid 201 are respectively provided with a pad 202 for electrical connection to an external circuit, thereby achieving electrical connection with the sensitive grid 201, and obtaining a resistance change signal generated when the sensitive grid 201 is deformed. The specific winding method and shape of the sensitive grid 201 are basically the same as those of the existing sensitive grid 201, and will not be repeated here.

[0043] The sensitive grid 201 is solidified on the surface of the substrate 1, which means that the sensitive grid 201 can be fixedly connected to the surface of the substrate 1 by an adhesive, so as to be connected to the substrate 1 as a whole, and the sensitive grid 201 is supported and protected by the substrate 1. After the sensitive grid 201 is solidified on the surface of the substrate 1, it can be kept flush with the surface of the substrate 1; or the surface of the substrate 1 is sunken inward to form a pit, and then the sensitive grid 201 is solidified in the pit, so as to be kept flush with the surface of the substrate 1; or the sensitive grid 201 protrudes from the surface of the substrate 1. The other side of the substrate 1 where the sensitive grid 201 is solidified is also fixed to the corresponding detection area of ​​the elastic arm by an adhesive, so that the strain gauge can be fixed on the elastic arm, so that the deformation of the elastic arm can be detected in a timely and sensitive manner.

[0044] Furthermore, each strain unit 20 is solidified on the same substrate 1 and fixed on the same surface of the elastic arm. In this way, when welding the pads 202 corresponding to each strain unit 20 to electrically connect the leads, since they are all on the same surface of the elastic arm, there is no need to adjust the welding position over a large range. Basically, all strain units 20 on the same integrated strain gauge 10 can be welded with leads at the same position, thereby improving the convenience of lead welding operation. Moreover, under this design, it can also be used for automatic wire binding machines to perform automatic welding operations on the leads of each strain unit 20, further improving the efficiency of lead welding.

[0045] In some embodiments, Figure 5 and Figure 6As shown, the strain unit group 2 includes a plurality of first strain units 21, two of each first strain unit 21 are arranged at intervals along the first direction, and at least two rows are arranged along the second direction, and the two first strain units 21 in the same row are symmetrically distributed on the substrate 1 relative to the second symmetry axis W; wherein, at least four corners of the substrate 1 are respectively provided with a first strain unit 21, and the projections of the first strain units 21 in different rows in the first direction are the same. Specifically, when a force in the Fx or Fy direction is applied, or a moment in the Mz direction is applied, the two opposite sides of each corresponding elastic arm are the places where deformation is more likely to occur, and each first strain is arranged in this way, and the shapes formed by each first strain unit 21 in each row are basically the same, and the contour shape finally formed by all the first strain units 21 is a rectangle. And at least four corners of the substrate 1 are respectively provided with a first strain unit 21. Thus, at least two first strain units 21 are arranged on the same side of the same elastic arm, and when they are attached to different elastic arms, the forces in the Fx and Fy directions and the moments in the Mz direction can be detected more sensitively. Thus, by adopting the above arrangement, not only the convenience and efficiency of the attachment arrangement are improved, but also the detection function that can be achieved by a single integrated strain gauge 10 is improved, so that the strain unit 20 to be connected can be selected according to the detection needs, and the flexibility of use is good.

[0046] In some embodiments, Figure 1 As shown, the strain unit group 2 also includes a plurality of second strain units 22, and at least one second strain unit 22 is arranged between two first strain units 21 in each row; wherein, each second strain unit 22 is spaced apart along the second direction, and each first strain unit 21 and second strain unit 22 in the same row are symmetrically distributed on the substrate 1 relative to the second symmetry axis W. Specifically, when a moment in the direction of Mx or My is applied, or a force in the direction of Fz is applied, the axial direction of each corresponding elastic arm is a place where deformation is more likely to occur. By adopting such a distribution method for each second strain unit 22, each second strain unit 22 can be distributed on the symmetry axis of the elastic arm in the width direction, and can more sensitively detect the moment in the directions of Mx and My and the force in the direction of Fz. Combined with multiple rows of first strain units 21 arranged on both sides, it is possible to achieve that all six detection channels have more sensitive detection performance, thereby improving the detection accuracy of the integrated strain gauge 10. In addition, a bridge arm on some of the detection channels can be connected to a plurality of strain units 20 located at different positions, thereby further improving the sensitivity and accuracy of the detection.

[0047] In the above, the structures and detection performances of the first strain units 21 and the second strain units 22 can be the same, and they can be regarded as the same strain unit 20, so that when performing the operation of curing on the substrate 1, there is no need to distinguish them, which improves the convenience of arrangement. In the embodiment of the present invention, in order to facilitate the description of the arrangement in various directions, the first strain unit 21 and the second strain unit 22 are distinguished, and the strain units 20 are not distinguished due to different structures.

[0048] In some embodiments, Figure 7 As shown, the strain unit group 2 also includes an inclined strain unit 23, at least two of which are provided, and each two inclined strain unit groups 2 form a group and are symmetrically arranged relative to the second symmetry axis W; wherein, the angle between the sensitive grid axial direction of the inclined strain unit 23 and the second symmetry axis W is between 0-75 degrees. Specifically, the inclined strain unit 23 can more sensitively detect deformations that are substantially the same as its inclined direction. By adjusting the inclined direction and the arrangement position of the inclined strain unit 23, it can be used for multi-channel detection, thereby improving the flexibility of detection. Moreover, due to the inclined setting, the distance to the side of the corresponding elastic arm is relatively close, so it also has the detection performance of the force in the Fx or Fy direction and the moment in the Mz direction. Combined with each first strain unit 21, it can be combined to form a corresponding Wheatstone bridge according to the detection requirements, thereby improving the sensitivity of the corresponding channel detection. In addition, by symmetrically arranging at least two of each inclined strain unit 23 relative to the second symmetry axis W, the sensitive grid axial direction of each inclined strain unit 23 on both sides is tilted toward two different directions, respectively, so that deformations in different directions can be detected respectively. In this way, with the mutual complementation of the detection functions of the inclined strain units 23 on both sides, the deformation occurring on the two sides in the same axial direction as the sensitive grid of each inclined strain unit 23 can basically be detected, further improving the sensitivity and accuracy of the detection.

[0049] In some embodiments, Figure 5 and Figure 6 As shown, the axial direction of the sensitive grid of each first strain unit 21 is the same. That is, the sensitive grid of each first strain unit 21 is arranged on the substrate 1 in the same manner in the axial direction, which can be parallel or perpendicular to the first direction, with a more flexible arrangement. Therefore, the axial distribution mode of the sensitive grid 201 of each first strain unit 21 can be selected according to the force direction to be measured to meet different detection requirements. Of course, it can be understood that the axial direction of the sensitive grid of at least each first strain unit 21 in the same row can also be the same. In this way, the first strain units 21 located at both ends are respectively close to the opposite sides of the same elastic arm, and the detection functions that can be achieved are the same, so that during detection, they can be combined to form the same Wheatstone bridge, and the detection is sensitive.

[0050] In some embodiments, Figure 8 and Fig. 9 As shown, each strain unit 20 is arranged at intervals along the second direction; wherein, the sensitive grids of at least two strain units 20 are axially arranged as vertical strain units 203 which are the same as the second direction, and the sensitive grids of at least two strain units 20 are axially arranged as oblique strain units 204 which are inclined at an angle to the second direction. In this way, in the second direction, each vertical strain unit 203 and each oblique strain unit 204 are arranged in the same column and are located on the symmetry axis of the elastic arm in the width direction. Thus, the vertical strain unit 203 can be used to detect the moment in the Mx or My direction and the force in the Fz direction. The oblique strain unit 204 can detect the force or moment which is tilted relative to the axial direction of the elastic arm and is in the same axial direction as the sensitive grid 201, thereby improving the comprehensiveness of the detection. This kind of one-piece strain gauge 10 has a common combination of vertical strain units 203 and oblique strain units 204, and has comprehensive detection functions and good sensitivity.

[0051] In some embodiments, Figure 8 As shown, along the second direction, at least one oblique strain unit 204 is located at the end of the second direction. Specifically, the oblique strain unit 204 located at the end can be arranged in an inclined direction according to the oblique working force to be detected, so that the oblique strain unit 204 can detect the oblique force or moment in the same axial direction as the sensitive grid 201, thereby improving the comprehensiveness of the detection.

[0052] In some embodiments, Fig. 9 As shown, along the second direction, at least one vertical strain unit 203 is respectively arranged on both sides of the oblique strain unit 204. Specifically, the same number of vertical strain units 203 can be respectively arranged on both sides of the oblique strain unit 204, or the number of vertical strain units 203 arranged on both sides is different. The specific setting method can be adjusted according to the scene to be applied, and the setting flexibility is good. The vertical strain unit 203 and the oblique strain unit 204 complement each other, which improves the sensitivity of detection.

[0053] In some embodiments, Figure 8 and Fig. 9 As shown, every two oblique strain units 204 are relatively inclined and symmetrically arranged relative to the second symmetry axis W. In this way, at least one oblique strain unit 204 is arranged on both sides of the symmetry axis, and the sensitive grids of the oblique strain units 204 on both sides are axially inclined toward two different directions, respectively, so that deformations in different directions can be detected respectively. In this way, under the mutual complementation of the detection functions of the oblique strain units 204 on both sides, deformations occurring on the two sides in the same axial direction as the sensitive grids of the oblique strain units 204 can be basically detected, further improving the sensitivity and accuracy of the detection.

[0054] like Figures 7 to 9 As shown, the oblique strain unit 204 has an axis of symmetry P, which is parallel to the axial direction of the sensitive grid. Therefore, the angle between the axial direction of the sensitive grid of the oblique strain unit 204 and the second direction can be considered as the angle between the axis of symmetry P and the second direction. In addition, the angle between the axial direction of the sensitive grid of the oblique strain unit 204 and the second direction is set between 0-75 degrees. Optionally, the angle between the two can be 15 degrees, or 45 degrees, or 60 degrees, or 75 degrees, and of course, it can also be any other value within the range of 0-75 degrees. Different angles correspond to different detection sensitivities under each channel, so the angle between the axial direction of the sensitive grid of the oblique strain unit 204 and the second direction can be set according to the requirements of the detection channel, and the setting flexibility is good.

[0055] In some embodiments, the strain unit group 2 can also be distributed on the substrate 1 to form an L-shape or an I-shape. Specifically, when the strain unit group 2 is distributed on the substrate 1 to form an L-shape, it is formed to have at least one first strain unit 21 on one side of the elastic arm and at least one second strain unit 22 in the second direction, and is distributed in parallel on the symmetry axis in the width direction of the elastic arm. This kind of structural distribution can meet the requirements of at least one of the three detection channels for detection on each elastic arm, and the selection flexibility is good. When the strain unit group 2 is distributed on the substrate 1 to form an I-shape, it can be applied to detection in more channels. For example, if the integrated strain gauge 10 of this structure is attached to an elastic arm perpendicular to the X-axis direction, it can be used for any type of detection among Fx, Fz, Mx or Mz. This integrated design of distributing the strain unit group 2 on the substrate 1 to form an L-shape or an I-shape, combined with the same arrangement on each elastic arm, can be used to detect forces in three different directions and moments in three different directions, meeting the detection requirements that can be used for six channels.

[0056] For ease of understanding, the integrated strain gauge 10 provided in the embodiment of the present invention is exemplified below in combination with the specific number of strain units 20 in the strain unit group 2 and the shapes in which they can be mainly distributed on the substrate 1. When setting, any of the following methods may be included. It is understandable that the arrangement shape of the strain unit group 2 is not limited. According to different detection needs, the arrangement shape of the strain unit group 2 can also be arranged in a manner other than the following examples.

[0057] The first way, such as Figure 5 and Figure 6As shown, the strain unit group 2 includes four first strain units, and the four first strain units 21 are evenly divided into two rows and respectively located at the four corners of the substrate 1; wherein, at least the sensitive grid axial directions of two first strain units 21 in the same row are the same and parallel to the first direction or parallel to the second direction; and the first direction and the second direction are perpendicular. Under this distribution mode, at least the following can be formed Figure 5 Neutralization Figure 6 The two different types shown have high detection sensitivity and can be selected according to specific application requirements. At the same time, multiple strain units 20 can be pasted at one time, and the patch operation is convenient and the pasting efficiency is high.

[0058] The second method, such as Figure 1 and Fig.10 As shown, the strain unit group 2 includes four first strain units 21 and two second strain units 22. The four first strain units 21 are evenly divided into two rows and are located at the four corners of the substrate 1; the two second strain units 22 are respectively arranged between the two first strain units 21 in each row; wherein the two first strain units 21 and one second strain unit 22 in the same row are symmetrically distributed on the substrate 1 relative to the second symmetry axis W; the axial direction of the sensitive grid of the first strain unit 21 in the same row is the same as or perpendicular to the axial direction of the sensitive grid of the second strain unit 22. Under this distribution mode, at least the following can be formed: Figure 1 Neutralization Fig.10 When each elastic arm is provided with such an integrated strain gauge 10 of the same shape, each detection channel can use four strain units 20 to form a Wheatstone full bridge circuit, so that six detection channels can form a Wheatstone full bridge circuit, and the detection sensitivity is high. In addition, multiple strain units 20 can be pasted at one time, and the patch operation is convenient and the pasting efficiency is high.

[0059] The third method, such as Figure 8 As shown, the strain unit group 2 includes four strain units 20; wherein, the sensitive grids of two strain units 20 are axially set to vertical strain units 203 which are the same as the second direction, and the sensitive grids of two strain units 20 are axially set to oblique strain units 204 which are inclined at an angle to the second direction, and the two oblique strain units 204 are relatively inclined and symmetrically set to form an oblique strain group relative to the second symmetry axis W; along the second direction, the oblique strain group is located at the end of the second direction; wherein, the angle between the sensitive grid axial direction of the oblique strain unit 204 and the second symmetry axis W is between 0-75 degrees. Under this distribution mode, combined with the oblique strain unit 204, the direction of sensing deformation can be further improved, and the sensitivity of detection can be improved. At the same time, the installation of multiple strain units 20 can be completed in one pasting, and the patch operation is convenient and the pasting efficiency is high.

[0060] The fourth method, such as Fig. 9 As shown, the strain unit group 2 includes six strain units 20; wherein, the sensitive grids of four strain units 20 are axially set to vertical strain units 203 that are the same as the second direction, and the sensitive grids of two strain units 20 are axially set to oblique strain units 204 that are inclined at an angle to the second direction, and the two oblique strain units 204 are relatively inclined and symmetrically set to form an oblique strain group relative to the second symmetry axis W; along the second direction, two vertical strain units 203 are equidistantly set on both sides of the oblique strain group; wherein, the angle between the sensitive grid axial direction of the oblique strain unit 204 and the second symmetry axis W is between 0-75 degrees. Under this distribution mode, combined with the oblique strain unit 204, the direction of the sensing deformation can be further improved, and the sensitivity of the detection can be improved. At the same time, the installation of multiple strain units 20 can be completed in one pasting, and the patch operation is convenient and the pasting efficiency is high.

[0061] The fifth method, such as Fig.11 As shown, the strain unit group 2 includes eight first strain units 21; the eight first strain units 21 are evenly divided into four rows along the second direction, each row is spaced apart, and at least one first strain unit 21 can be set in the gap between the second row and the third row; wherein, a first strain unit 21 is respectively set at the four corners of the substrate 1; the sensitive grid axis of the first strain unit 21 in the same row is parallel to the second direction. Under this distribution mode, multiple first strain units 21 are set on the two opposite sides of each elastic arm, which can be used for the detection of multiple channels and has high detection sensitivity. At the same time, the installation of multiple strain units 20 can be completed in one pasting, and the patch operation is convenient and the pasting efficiency is high.

[0062] The sixth method, such as Figure 7 As shown, the strain unit group 2 includes six first strain units 21 and two inclined strain units 23. The six first strain units 21 are evenly divided into three rows along the second direction, and each row is spaced apart, and the gap between the second row and the third row can be at least two first strain units 21 arranged in parallel and at equal intervals; the two inclined strain units 23 are relatively inclined to form a group, and are symmetrically arranged relative to the second symmetry axis W; wherein, a first strain unit 21 is respectively arranged at the four corners of the substrate 1; the two inclined strain units 23 are located between the second row and the third row; the angle between the sensitive grid axis of the inclined strain unit 23 and the second symmetry axis W is between 0-75 degrees. Under this distribution mode, combined with the inclined strain unit 23, the direction of the sensing deformation can be further improved, and the sensitivity of the detection can be improved. At the same time, the installation of multiple strain units 20 can be completed in one pasting, and the patch operation is convenient and the pasting efficiency is high.

[0063] The seventh method, such as Fig.12As shown, the strain unit group 2 includes eight first strain units 21 and four second strain units 22. The eight first strain units 21 are evenly divided into four rows along the second direction, and each row is spaced apart, and at least one first strain unit 21 can be set in the gap between the second row and the third row; the four second strain units 22 are respectively arranged between the two first strain units 21 in each row, and the spacing is equal to that between the two first strain units 21 in the same row; wherein, a first strain unit 21 is respectively arranged at the four corners of the substrate 1. Under this distribution mode, when such an integrated strain gauge 10 of the same shape is arranged on each elastic arm, each detection channel can use four strain units 20 to form a Wheatstone full bridge circuit, and it can be realized that six detection channels can form a Wheatstone full bridge circuit, and the detection sensitivity is high. In addition, the installation of multiple strain units 20 can be completed in one pasting, and the patch operation is convenient and the pasting efficiency is high.

[0064] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An integrated strain gauge, used to be arranged on each elastic arm of a force sensor, characterized in that: The integrated strain gauge comprises: A base, wherein the outline of the base is set to be a rectangle; A strain unit group, wherein the strain unit group is symmetrically distributed on the substrate and solidified on the surface of the substrate; The strain unit group can be used to detect forces in three different directions and moments in three different directions.

2. The integrated strain gauge according to claim 1, characterized in that: The substrate at least includes a first symmetry axis located in a first direction and a second symmetry axis located in a second direction, and the first direction is perpendicular to the second direction; wherein the strain unit group includes at least four strain units, each of the strain units is symmetrically distributed on the substrate at least relative to the second symmetry axis, and each of the strain units includes a sensitive gate and a pad connecting two ends of the sensitive gate.

3. The integrated strain gauge according to claim 2, characterized in that: The strain unit group includes a plurality of first strain units, two of each first strain unit are arranged at intervals along the first direction, and at least two rows are arranged along the second direction, and two first strain units in the same row are symmetrically distributed on the substrate relative to the second symmetry axis; wherein one first strain unit is respectively arranged at at least four corners of the substrate; and projections of the first strain units in different rows in the first direction are the same.

4. The integrated strain gauge according to claim 3, characterized in that: The strain unit group also includes a plurality of second strain units, and at least one second strain unit is arranged between two first strain units in each row; wherein the second strain units are spaced apart along the second direction, and the first strain units and the second strain units in the same row are symmetrically distributed on the substrate relative to the second symmetry axis.

5. The integrated strain gauge according to claim 3, characterized in that: The strain unit group also includes an inclined strain unit, at least two of which are provided, and every two of the inclined strain units form a group and are symmetrically arranged relative to the second symmetry axis; wherein the angle between the sensitive grid axis of the inclined strain unit and the second symmetry axis is between 0-75 degrees.

6. The integrated strain gauge according to claim 3 or 4, characterized in that: The sensitive grids of the first strain units have the same axial direction; or at least the sensitive grids of the first strain units in the same row have the same axial direction.

7. The integrated strain gauge according to claim 2, characterized in that: The strain units are arranged at intervals along the second direction; wherein, the sensitive grids of at least two of the strain units are axially arranged as vertical strain units in the same direction as the second direction, and the sensitive grids of at least two of the strain units are axially arranged as oblique strain units inclined at an angle to the second direction.

8. The integrated strain gauge according to claim 7, characterized in that: Along the second direction, at least one of the oblique strain units is located at an end of the second direction; Or along the second direction, at least one vertical strain unit is respectively arranged on both sides of the oblique strain unit.

9. The integrated strain gauge according to claim 7, characterized in that: Every two of the oblique strain units are inclined relative to each other and are symmetrically arranged relative to the second symmetry axis.

10. The integrated strain gauge according to claim 1, characterized in that: The distribution of the strain unit group includes any one of the following methods: 1) The strain unit group includes four first strain units, which are divided into two rows and respectively located at four corners of the substrate; wherein at least two of the first strain units in the same row have the same axial direction of the sensitive grids, which are parallel to the first direction or the second direction; and the first direction is perpendicular to the second direction; 2) The strain unit group includes four first strain units and two second strain units, the four first strain units are divided into two rows and are located at the four corners of the substrate; two second strain units are respectively arranged between the two first strain units in each row; wherein the two first strain units and one second strain unit in the same row are symmetrically distributed on the substrate relative to the second symmetry axis; the axial direction of the sensitive grid of the first strain unit in the same row is the same as or perpendicular to the axial direction of the sensitive grid of the second strain unit; 3) The strain unit group includes four strain units; wherein the sensitive grids of two of the strain units are axially arranged as vertical strain units that are the same as the second direction, and the sensitive grids of two of the strain units are axially arranged as oblique strain units that are inclined at an angle to the second direction, and the two oblique strain units are relatively inclined and symmetrically arranged relative to the second symmetry axis to form an oblique strain group; along the second direction, the oblique strain group is located at the end of the second direction; wherein the angle between the sensitive grid axial direction of the oblique strain gauge and the second symmetry axis is between 0 and 75 degrees; 4) The strain unit group includes six strain units; wherein the sensitive grids of four of the strain units are axially arranged as vertical strain units that are the same as the second direction, and the sensitive grids of two of the strain units are axially arranged as oblique strain units that are inclined at an angle to the second direction, and the two oblique strain units are relatively inclined and symmetrically arranged relative to the second symmetry axis to form an oblique strain group; along the second direction, two vertical strain units are equidistantly arranged on both sides of the oblique strain group; wherein the angle between the sensitive grid axial direction of the oblique strain unit and the second symmetry axis is between 0 and 75 degrees; 5) The strain unit group includes eight first strain units; the eight first strain units are evenly divided into four rows along the second direction, each row is spaced apart, and at least one first strain unit can be arranged in the gap between the second row and the third row; wherein one first strain unit is arranged at each of the four corners of the substrate; the sensitive grid axis of the first strain units in the same row is parallel to the second direction; 6) The strain unit group includes six first strain units and two inclined strain units, the six first strain units are evenly divided into three rows along the second direction, each row is spaced, and the gap between the second row and the third row can be arranged in parallel with at least two first strain units at equal intervals; the two inclined strain units are relatively inclined to form a group, and are symmetrically arranged relative to the second symmetry axis; wherein one first strain unit is respectively arranged at the four corners of the substrate; the two inclined strain units are located between the second row and the third row; the angle between the sensitive grid axis of the inclined strain unit and the second symmetry axis is between 0-75 degrees; 7) The strain unit group includes eight first strain units and four second strain units, the eight first strain units are evenly divided into four rows along the second direction, each row is spaced apart, and at least one first strain unit can be arranged in the gap between the second row and the third row; four second strain units are respectively arranged between two first strain units in each row, and the spacing is equal to that between two first strain units in the same row; wherein one first strain unit is respectively arranged at the four corners of the substrate.

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