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 strain unit group comprises at least three strain units, each strain unit is solidified on the surface of the substrate, and each strain unit comprises a sensitive grid and a bonding pad connected with the two ends of the sensitive grid. Moreover, the strain unit group can be used for detecting forces in three different directions and moments in three different directions. According to the strain gauge, the at least three strain units are arranged on the same substrate, so that the arrangement of the at least three strain units can be completed at a time only through one-time pasting, one-by-one pasting is not needed, and the convenience and the efficiency of pasting the strain gauge are improved. Moreover, the integrated strain gauge is provided with at least three strain units, so that the integrated strain gauge 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; a strain unit group, comprising at least three strain units, each of which is solidified on the surface of the substrate, and each of which comprises a sensitive grid and a pad connecting two ends of the sensitive grid; 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 in an embodiment of the present invention includes a substrate and a strain unit group. The strain unit group includes at least three strain units, each of which is solidified on the surface of the substrate, and each of which includes a sensitive grid and a pad connecting the two ends of the sensitive grid. In addition, the set strain unit group can be used to detect forces in three different directions and torques in three different directions. In this way, the embodiment of the present invention adopts the method of setting at least three strain units on the same substrate, so that when the operation of pasting them on the elastic arm is performed, only one pasting is required to complete the arrangement of at least three strain units at one time, without the need to paste them one by one, thereby improving the convenience and efficiency of strain gauge pasting. In addition, by setting at least three strain units, the integrated strain gauge has the function of detecting forces in three different directions and torques 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 This is the principle diagram of the Wheatstone bridge;

[0010] Figure 3 It is a schematic diagram of the integrated strain gauge used for six detection channels;

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

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

[0013] Figure 6 is a schematic diagram of the structure of another integrated strain gauge provided by an embodiment of the present invention, showing two different types;

[0014] Figure 7 is a schematic diagram of the structure of another integrated strain gauge provided by an embodiment of the present invention, showing three different types;

[0015] Figure 8 is a schematic diagram of the structure of another integrated strain gauge provided by an embodiment of the present invention, showing two different types;

[0016] Fig. 9 is a schematic diagram of the structure of another integrated strain gauge provided by an embodiment of the present invention, showing two different types;

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

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

[0019] Fig.12 is a structural schematic diagram of another integrated strain gauge provided by an embodiment of the present invention;

[0020] Fig.13 It is a schematic structural diagram of another integrated strain gauge provided in an embodiment of the present invention.

[0021] Description of reference numerals:

[0022] 10. Integrated strain gauge; 1. substrate; 21. strain unit; 211. sensitive grid; 212. pad; 22. first strain unit; 23. second strain unit; 231. inclined strain unit; P. symmetry axis. DETAILED DESCRIPTION

[0023] 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.

[0024] 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.

[0025] 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.

[0026] 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.

[0027] like Figure 1 As shown, an integrated strain gauge 10 provided by an embodiment of the present invention is used to be arranged on each elastic arm of a force sensor. Specifically, a strain gauge is pasted on the detection position of each elastic arm, so that the force or torque acting on the elastic arm can be detected by the strain gauge. The working principle of the force sensor is as follows: when an external force or torque acts on the sensor, the elastic arm will undergo a slight deformation (such as a change in length or cross-sectional area), and this deformation will be transmitted to the strain gauge pasted on 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 (refer to Figure 2). When the resistance value of the strain gauge changes, the balance state of the bridge circuit will be broken, thus generating an output signal proportional to the mechanical quantity. After being amplified, filtered and digitized by the signal processing circuit, this signal can be read and analyzed by terminal devices such as computers, and the corresponding force conditions can be obtained.

[0028] 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 3 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.

[0029] 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.

[0030] 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.

[0031] like Figure 2 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.

[0032] 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.

[0033] 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.

[0034] like Figure 1 As shown, the integrated strain gauge 10 provided in the embodiment of the present invention includes a substrate 1 and a strain unit group. The substrate 1 is a thin sheet structure, which is pasted on the elastic arm to transmit strain. The strain unit group is solidified on the substrate 1 and can undergo elastic deformation with the substrate 1. Specifically, the strain unit group includes at least three strain units 21, each of which is solidified on the surface of the substrate 1, and each of which includes a sensitive grid 211 and a pad 212 connecting the two ends of the sensitive grid 211. That is, at least three strain units 21 are arranged on the same substrate 1, and each strain unit 21 is independent of each other and is used to respectively realize the required detection function. The sensitive grid 211 is usually made of a filament 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. There are pads 212 at both ends of the sensitive grid 211 for electrical connection to the external circuit, thereby realizing electrical connection with the sensitive grid 211, so that the resistance change signal generated when the sensitive grid 211 is deformed can be obtained. The specific winding method and shape of the sensitive grid 211 are substantially the same as those of the existing sensitive grid 211 , and will not be described in detail herein.

[0035] The sensitive grid 211 is solidified on the surface of the substrate 1, which means that the sensitive grid 211 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 211 is supported and protected by the substrate 1. After the sensitive grid 211 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 211 is solidified in the pit, so as to be kept flush with the surface of the substrate 1; or the sensitive grid 211 protrudes from the surface of the substrate 1. The other side of the substrate 1 where the sensitive grid 211 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.

[0036] Specifically, in an embodiment of the present invention, at least three strain units 21 are provided to form a strain unit group, and the strain unit group 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 21, so as to realize the 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 can be set according to the detection needs (such as increasing the number of strain units 21), 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 21 can detect six channels, and in the actual detection process, it is not necessary for each strain unit 21 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 at least three strain units 21 and one body, thereby improving the detection function and having good practicality.

[0037] In the embodiment of the present invention, at least three strain units 21 are integrated and fixed on the same substrate 1. In this way, at least three strain units 21 can be attached by fixing the substrate 1 on the elastic arm once. That is, at least three strain units 21 can be attached at one time without pasting them one by one, which saves the steps of attaching the strain gauges, thereby improving the efficiency of attaching the strain gauges. In addition, the position and firmness of each strain unit 21 fixed on the substrate 1 have been completed in advance, so when attaching and fixing them on the elastic arm, it is only necessary to ensure the accuracy of the attachment position of the substrate 1 to achieve accurate attachment of each strain unit 21, and at the same time, it can also ensure the consistency of the attachment of each strain unit 21, so that each strain unit 21 can detect the deformation of the elastic arm in time, thereby improving the sensitivity and accuracy of the detection of each strain unit 21 attached to the elastic arm.

[0038] Furthermore, at least three strain units 21 are provided on the same substrate 1 and are glued and fixed on the same surface of the elastic arm. In this way, when welding the electrical connection leads to the pads 212 corresponding to each strain unit 21, 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, the leads of all strain units 21 on the same integrated strain gauge 10 can be welded at the same position, thereby improving the convenience of the lead welding operation. Moreover, under this design, it can also be used for the automatic wire binding machine to perform the automatic welding operation of the leads on each strain unit 21, further improving the efficiency of the lead welding.

[0039] The integrated strain gauge 10 provided in the embodiment of the present invention includes a substrate 1 and a strain unit group. By setting the strain unit group to include at least three strain units 21, each strain unit 21 is solidified on the surface of the same substrate 1. 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 setting at least three strain units 21 on the same substrate 1, when the operation of pasting on the elastic arm is performed, only one pasting is required to complete the arrangement of at least three strain units 21 at one time, without the need to paste them one by one, thereby improving the convenience and efficiency of strain gauge pasting. At the same time, by setting at least three strain units 21, the integrated strain gauge 10 has the function of detecting forces in three different directions and moments in three different directions, with diverse detection functions and good detection sensitivity, and can better meet different detection needs. At the same time, the integrated strain gauge 10 is pasted and fixed on the same surface of the elastic arm. When welding the leads of each strain unit 21, there is no need to make a large position adjustment, so the leads of all the strain units 21 on the same integrated strain gauge 10 can be welded, and the demand for automatic wire binding can be met, thereby improving the efficiency of welding the leads of each strain unit 21.

[0040] 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.

[0041] In some embodiments, Figure 1As shown, the strain unit group is distributed on the substrate 1 to form a T-shape, and the T-shape includes a first direction and a second direction that may intersect, and each strain unit 21 is arranged on one of the first direction and the second direction. Specifically, the first direction and the second direction may be two directions that intersect each other perpendicularly, or two directions that intersect each other obliquely. The strain unit group is distributed in a T-shape on the substrate 1, which means that the shape formed by at least three strain units 21 is basically T-shaped, and at least two strain units 21 may be distributed at intervals along the first direction, and at least one strain unit 21 may be distributed at intervals on one side along the second direction. The shape of the substrate 1 is not limited, as long as it can meet the distribution requirements of each strain unit 21.

[0042] Specifically, each strain unit 21 is regarded as a point, and the strain units 21 distributed at intervals in the first direction are on the same straight line, and the strain units 21 distributed in the second direction are also on the same straight line. The two straight lines in different directions intersect vertically or obliquely, and can form a roughly T-shaped shape. Therefore, after the integrated strain gauge 10 is pasted to each elastic arm, at least the two strain units 21 located at the two ends of the first direction are respectively close to the two opposite sides of the corresponding elastic arm, which can be used to more sensitively detect the forces in the Fx and Fy directions and the torque in the Mz direction. The strain units 21 located in the second direction are close to the middle of the corresponding elastic arm in the width direction (compared with the two strain units 21 located at the two ends of the first direction, they are closer to the symmetry axis of the elastic arm in the width direction), which can be used to more sensitively detect the torque in the Mx and My directions and the force in the Fz direction. By adopting the above-mentioned settings, the detection function that can be achieved by a single integrated strain gauge 10 is improved, so that the strain unit 21 to be connected can be selected according to the detection needs, and the flexibility of use is good.

[0043] In some embodiments, Figure 5As shown, the strain unit group includes at least two first strain units 22 arranged at intervals in the first direction and at least one second strain unit 23 arranged in the second direction. Moreover, the projection of the second strain unit 23 in the first direction is located between the two first strain units 22 at both ends of the first direction, and the second strain unit 23 is arranged on one side of the first direction; the first direction and the second direction are perpendicular. In this way, each of the two opposite sides of each elastic arm has at least one first strain unit 22, and at the same time, at least one second strain unit 23 is also arranged on the axis of the elastic arm in the width direction. 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 places where deformation is more likely to occur. At the same time, when a moment in the Mx or My direction is applied, or a force in the Fz direction is applied, the axial direction of each corresponding elastic arm is a place where deformation is more likely to occur. Therefore, by setting the strain unit group in the above manner, each first strain unit 22 and each second strain unit 23 can more sensitively detect the deformation of the elastic arm, so that the integrated strain gauge 10 has reliable detection performance.

[0044] 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 paper. The structures and detection performances of the first strain units 22 and the second strain units 23 can be the same, and they can be regarded as the same strain unit 21, 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 22 and the second strain unit 23 are distinguished, and the strain units 21 are not distinguished due to different structures.

[0045] In some embodiments, Figure 6 a and Figure 6 As shown in FIG. 2 , the second strain unit 23 arranged along the second direction includes an inclined strain unit 231, and the angle between the sensitive grid axis of the inclined strain unit 231 and the second direction is between 0 and 75 degrees. In this way, the inclined strain unit 231 can more sensitively detect deformation that is substantially the same as its inclined direction. By adjusting the inclined direction and the arrangement position of the inclined strain unit 231, it can be used for multi-channel detection, thereby improving the flexibility of detection. Specifically, the inclined strain unit 231 can not only be used for the detection of torque in the Mx or My direction and force in the Fz direction, but also, due to the inclined setting, the distance from the side of the corresponding elastic arm is closer, so it also has the detection performance of force in the Fx or Fy direction and torque in the Mz direction. Therefore, it can be combined to form a corresponding Wheatstone bridge according to the detection requirements, with ingenious design and good flexibility.

[0046] Specifically, the axial direction of the sensitive grid usually refers to the direction in which it is aligned with the axis of the elastic arm (usually the direction of the force) when installed, so as to ensure that the sensitive grid 211 can accurately measure the deformation of the elastic arm in this direction. Figure 6 a and Figure 6 As shown in FIG. 2 b, the inclined strain unit 231 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 inclined strain unit 231 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 inclined strain unit 231 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. 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 inclined strain unit 231 and the second direction can be set according to the requirements of the detection channel, and the setting flexibility is good.

[0047] In some embodiments, Figure 7 As shown, at least two inclined strain units 231 are symmetrically arranged relative to the second direction. In this way, at least one inclined strain unit 231 is arranged on both sides of the symmetry axis. Moreover, the sensitive grid axial direction of each inclined strain unit 231 on both sides is tilted towards two different directions, so that deformations in different directions can be detected respectively. In this way, under the mutual complementation of the detection functions of each inclined strain unit 231 on both sides, deformations occurring on the two sides in the same axial direction as the sensitive grid axial direction of each inclined strain unit 231 can basically be detected, further improving the sensitivity and accuracy of detection.

[0048] In some embodiments, Figure 6 and Figure 7 As shown, at least one second strain unit 23 can be arranged between the oblique strain unit 231 and at least one first strain unit 22. Specifically, the oblique strain unit 231 is arranged along the second direction, and a certain interval is provided between the first oblique strain unit 231 and the first strain unit 22, and the length of the interval distance satisfies that at least one second strain unit 23 can be arranged. In this way, by arranging another second strain unit 23 between the first oblique strain unit 231 and the first strain unit 22, the second strain unit 23 and the oblique strain unit 231 can sense different directions of force, and by combining with each other, the force condition can be detected more comprehensively, thereby improving the comprehensiveness and sensitivity of the detection, and improving the overall accuracy of the force condition detection.

[0049] The inclined strain unit 231 adopts the above-mentioned arrangement, so that in the second direction, it is located at least in the third row of the substrate 1, and the second row is used to arrange a strain unit 21 with a sensitive grid axis in the same direction as the second direction. On the basis of ensuring the reliability of the detection function, the inclined strain unit 231 is set to further improve the comprehensiveness of the deformation detection of the elastic arm.

[0050] In some embodiments, Figure 8 As shown, the first strain units 22 are arranged in multiple rows along the second direction, and the first strain units 22 in the same row are arranged at equal intervals and symmetrically relative to the second direction; the projections of the first strain units 22 in different rows on the first direction are the same. In this way, the multiple first strain units 22 are arranged in multiple rows along the second direction, and the number of first strain gauges arranged in each row can be made equal. Moreover, each first strain unit 22 in each row can be combined with each second strain unit in the second direction to form a T-shape. Thus, each first strain unit 22 is distributed to form multiple rows, and can constitute multiple T-shaped structures (refer to Figure 8 a and Figure 8 b). In addition, the first strain units 22 at both ends of each row are respectively close to the two opposite sides of the corresponding elastic arm, and when multiple T-shaped structures are formed, multiple first strain units 22 can be distributed on the two opposite sides of the same elastic arm. With such a configuration, multiple first strain units 22 can be combined according to detection needs, and then used for detection of different channels, which can be used for detection with good flexibility. At the same time, when each elastic arm adopts an integrated strain gauge 10 of this structure, the first strain unit 22 and the second strain unit 23 at different positions can be selected for bridge combination to form any one of the full bridge, half bridge and 1 / 4 bridge in the Wheatstone bridge, which is flexible to choose. In addition, a bridge arm on some of the detection channels can be connected with multiple strain units 21 at different positions, which can further improve the sensitivity and accuracy of the detection.

[0051] In some embodiments, Figure 8As shown, the sensitive grid axis of the first strain unit 22 located at both ends of the first direction is parallel or perpendicular to the first direction. That is, the sensitive grid axis of each first strain unit 22 arranged at both ends of the first direction is kept the same, which can be parallel or perpendicular to the first direction, and has a more flexible setting mode. Therefore, the axial distribution mode of the sensitive grid of each first strain unit 22 located at both ends can be selected according to the force direction to be measured, so as to improve the sensitivity of detection. In addition, since the first strain units 22 located at both ends are arranged at intervals, there is a situation where no first strain unit 22 is set or another first strain unit 22 is set between two first strain units 22. In the case of the first strain unit 22 located between the two ends of the first direction, the sensitive grid axis of the first strain unit 22 located between the two ends of the first direction is perpendicular to the first direction. In this way, the sensitive grid axis of the first strain unit 22 located between the two ends is always kept the same as the second direction. Therefore, each first strain unit 22 located in the middle can be mainly used to detect the force in the Fz direction and the torque in the Mx or My direction, which can be used for at least one of the three detection channels for detection, and the design is more ingenious.

[0052] In some embodiments, the strain unit group can also be distributed on the substrate 1 to form an L-shape or an I-shape. Specifically, when the strain unit group is distributed on the substrate 1 to form an L-shape, it is formed to have at least one first strain unit 22 on one side of the elastic arm and at least one second strain unit 23 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 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 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.

[0053] In some embodiments, Figure 1 As shown, the pads 212 between different strain units 21 are arranged at intervals, so that each strain unit 21 is independent of each other, and the generated signals will not affect each other, which is beneficial to improve the sensitivity of detection.

[0054] In some embodiments, the contour shape of the substrate 1 can be set to any shape under the premise of satisfying the arrangement of the strain unit group and being able to be attached to the elastic arm. In other embodiments, such as Figure 1As shown, the outline of the substrate 1 can also be formed into a T-shape. In this way, the substrate 1 of this shape at least satisfies the requirement that the strain unit group can be distributed into an L-shape or a T-shape. Moreover, when the strain unit group is arranged into an L-shape or a T-shape, the substrate 1 of this shape can also preliminarily know the position and shape type of each strain unit 21 to be arranged according to the shape of the substrate 1 itself when the strain unit group is arranged into an L-shape or a T-shape. At this time, the shape of the substrate 1 plays a role in guiding the arrangement, thereby improving the accuracy of the position of each strain unit 21 when arranged and the convenience of the arrangement.

[0055] 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 21 in the strain unit group and the shapes that can be mainly distributed on the substrate 1. When setting, any of the following methods can be included. It can be understood that the arrangement shape of the strain unit group is not limited. According to different detection needs, the arrangement shape of the strain unit group can also be arranged in a manner other than the following examples.

[0056] The first way, such as Figure 5 and Figure 8 As shown, three shapes of strain unit groups composed of the same number of strain units 21 can be distributed. Specifically, the strain unit group includes six first strain units 22 and two second strain units 23. The six first strain units 22 are arranged in two rows parallel to the first direction, and three are arranged in each row at equal intervals; the two second strain units 23 are distributed along the second direction; wherein the first strain unit 22 located in the middle of each row is arranged in parallel with the two second strain units 23; at least the sensitive grid axial direction of the first strain units 22 located at both ends of the first direction in each row is the same, and is parallel to or perpendicular to the first direction. The first direction and the second direction are perpendicular to each other. Under this distribution method, at least the following can be formed. Figure 5 As well as Figure 8 There are three different types shown in Figures 8a and 8b. When the same shape of the integrated strain gauge 10 is provided on each elastic arm, four strain units 21 can be used in each detection channel to form a Wheatstone full bridge circuit, so that all six detection channels can form a Wheatstone full bridge circuit, with high detection sensitivity. In addition, multiple strain units 21 can be attached at one time, with high attachment efficiency.

[0057] The second method, such as Figure 7As shown in Fig. c, the strain unit group includes six first strain units 22 and two second strain units 23. The six first strain units 22 are arranged in two rows parallel to the first direction, and three are arranged at equal intervals in each row; the two second strain units 23 are arranged symmetrically relative to the second direction, and the angles between the sensitive grid axes of the two second strain units 23 and the second direction are between 0 and 75 degrees; wherein the symmetry axes of the two second strain units 23 are collinear with the symmetry axes of the three first strain units 22 in each row; and the first direction and the second direction are perpendicular. 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 21 to form a Wheatstone full bridge circuit, so that all six detection channels can form a Wheatstone full bridge circuit, and the detection sensitivity is high. It can also be combined with two second strain units 23 arranged relatively tilted, which can further improve the direction of the deformation and enhance the detection sensitivity. At the same time, the pasting of multiple strain units 21 can be completed in one pasting, and the pasting efficiency is high.

[0058] The third method, such as Figure 6 As shown in FIG. 1 , the strain unit group includes three first strain units 22 and four second strain units 23. The three first strain units 22 are arranged in a row at equal intervals along the first direction, and the sensitive grids of the first strain units 22 at both ends have the same axial direction; the four second strain units 23 are distributed at intervals along the second direction, and are arranged in parallel with the first strain unit 22 in the middle; wherein the angle between the axial direction of the sensitive grid of one of the first strain units 22 in the four second strain units 23 and the second direction is between 0 and 75 degrees, and the following can be formed: Figure 6 a picture and Figure 6 b shows two different types; and the first direction is perpendicular to the second direction. Under this distribution mode, combined with the second strain unit 23 set obliquely, the direction of sensing deformation can be further improved, and the sensitivity of detection can be improved. At the same time, multiple strain units 21 can be attached at one time, and the attachment efficiency is high.

[0059] The fourth method, such as Figure 7As shown in a, the strain unit group includes three first strain units 22 and five second strain units 23. The three first strain units 22 are arranged in a row at equal intervals along the first direction, and the sensitive grid axial direction of at least the first strain units 22 at both ends is the same; the five second strain units 23 are distributed at intervals along the second direction and are arranged in parallel with the first strain unit 22 located in the middle; wherein, two of the five second strain units 23 are symmetrically inclined relative to the second direction, and the angle between the axis of symmetry and the second direction is between 0-75 degrees, and the sensitive grid axial direction of three of the five second strain units 23 is the same as the second direction; and the first direction and the second direction are perpendicular. Under this distribution mode, combined with two second strain units 23 arranged relatively inclined, the direction of sensing deformation can be further improved, and the sensitivity of detection can be improved. At the same time, the pasting of multiple strain units 21 can be completed in one pasting, and the pasting efficiency is high.

[0060] The fifth method, such as Figure 7 As shown in Figure c, the strain unit group includes three first strain units 22 and three second strain units 23. The three first strain units 22 are arranged in a row at equal intervals along the first direction, and the sensitive grids of at least the first strain units 22 at both ends have the same axial direction; the three second strain units 23 are distributed at intervals along the second direction, and are arranged in parallel with the first strain unit 22 in the middle; wherein two of the three second strain units 23 are arranged symmetrically and tilted relative to the second direction, and the angle between the axis of symmetry and the second direction is between 0 and 75 degrees, and the sensitive grid of one of the three second strain units 23 is axially the same as the second direction; and the first direction and the second direction are perpendicular. Under this distribution mode, two second strain units 23 arranged relatively tilted can be combined to further improve the direction of sensing deformation and enhance the sensitivity of detection. At the same time, the pasting of multiple strain units 21 can be completed in one pasting, and the pasting efficiency is high.

[0061] The sixth method, such as Fig. 9 As shown, the strain unit group includes three first strain units 22 and two second strain units 23, the three first strain units 22 are arranged in a row at equal intervals along the first direction, and the sensitive grid axial directions of at least the first strain units 22 located at the two ends are in the same direction; the two second strain units 23 are distributed at intervals along the second direction, and are arranged in parallel with the first strain unit 22 located in the middle; wherein the angle between the sensitive grid axial direction of one of the two second strain units 23 and the second direction is between 0-75 degrees, and the sensitive grid axial direction of the other of the two second strain units 23 is in the same direction as the second direction, which can be formed as follows Fig. 9 a picture and Fig. 9b shows two different types; the first direction and the second direction are perpendicular. Under this distribution mode, at least the following can be formed Figure 1 The two different types shown in Figures a and b in the figure, combined with the second strain unit 23 set obliquely, can further improve the direction of sensing deformation and enhance the sensitivity of detection. At the same time, multiple strain units 21 can be attached at one time, and the attachment efficiency is high.

[0062] The seventh method, such as Figure 1 As shown, the strain unit group includes three first strain units 22 and one second strain unit 23. The three first strain units 22 are arranged in a row at equal intervals along the first direction, and the sensitive grids of the first strain units 22 at both ends have the same axial direction; the second strain units 23 are distributed along the second direction and arranged in parallel with the first strain unit 22 in the middle; and the first direction and the second direction are perpendicular. Under this distribution mode, it has a higher detection sensitivity. At the same time, multiple strain units 21 can be pasted once, and the pasting efficiency is high.

[0063] The eighth method, such as Fig.10 As shown, the strain unit group includes two first strain units 22 and one second strain unit 23, the two first strain units 22 are arranged at intervals along the first direction, and the sensitive grids of the two first strain units 22 have the same axial direction; the second strain unit 23 is distributed along the second direction and is located on one side of the two first strain units 22 in the second direction; wherein no strain unit is arranged between the two first strain units 22, and the second strain unit 23 is located on the symmetry axis between the two first strain units 22; and the first direction and the second direction are perpendicular. Under this distribution mode, the number of strain units 21 arranged on each integrated strain gauge 10 is small, and it has good convenience in setting and good detection sensitivity. At the same time, the installation of multiple strain units 21 can be completed in one pasting, and the pasting efficiency is high.

[0064] The ninth method, such as Fig.11 As shown, the strain unit group includes two first strain units 22 and two second strain units 23, the two first strain units 22 are arranged at intervals along the first direction, and the sensitive grids of the two first strain units 22 have the same axial direction; the two second strain units 23 are arranged in parallel and at intervals along the second direction, and are located on one side of the two first strain units 22 in the second direction; wherein each second strain unit 23 is located on the symmetry axis between the two first strain units 22; and the first direction is perpendicular to the second direction. Under this distribution mode, the number of strain units 21 arranged on each integrated strain gauge 10 is small, which has good convenience in setting and good detection sensitivity. At the same time, the installation of multiple strain units 21 can be completed in one pasting, and the pasting efficiency is high.

[0065] The tenth method, such as Fig.12 As shown, the strain unit group includes three first strain units 22 and three second strain units 23. The three first strain units 22 are arranged in a row at equal intervals along the first direction, and the sensitive grids of the first strain units 22 have the same axial direction; the three second strain units 23 are arranged in parallel with the first strain unit 22 in the middle along the second direction; wherein the three second strain units 23 are spaced apart; and the first direction and the second direction are perpendicular. Under this distribution mode, the integrated strain gauge 10 has good detection sensitivity. At the same time, the pasting of multiple strain units 21 can be completed in one pasting, and the pasting efficiency is high.

[0066] The eleventh method, such as Fig.13 As shown, the strain unit group includes five first strain units 22 and one second strain unit 23. The five first strain units 22 are distributed in two rows along the second direction. The first row has two strain units 22 spaced apart along the first direction, and the second row has three strain units 22 spaced apart along the first direction. The sensitive grids of the first strain units 22 have the same axial direction. The second strain unit 23 is arranged in parallel with the first strain unit 22 in the middle along the second direction. The first direction and the second direction are perpendicular. In this distribution mode, the integrated strain gauge 10 has good detection sensitivity. At the same time, the pasting of multiple strain units 21 can be completed in one pasting, and the pasting efficiency is high.

[0067] 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: substrate; A strain unit group, comprising at least three strain units, each of which is solidified on the surface of the substrate, and each of which comprises a sensitive grid and a pad connecting two ends of the sensitive grid; 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 strain unit group is distributed on the substrate to form a T-shape, wherein the T-shape includes a first direction and a second direction that may intersect, and each of the strain units is arranged in one of the first direction and the second direction.

3. The integrated strain gauge according to claim 1 or 2, characterized in that: The strain unit group includes at least two first strain units spaced apart in the first direction and at least one second strain unit arranged in the second direction; wherein a projection of the second strain unit in the first direction is located between the two first strain units at both ends of the first direction, and the second strain unit is arranged on one side of the first direction; and the first direction is perpendicular to the second direction.

4. The integrated strain gauge according to claim 3, characterized in that: The second strain unit comprises an inclined strain unit, and the angle between the sensitive grid axial direction of the inclined strain unit and the second direction is between 0-75 degrees.

5. The integrated strain gauge according to claim 4, characterized in that: At least two inclined strain units are symmetrically arranged relative to the second direction.

6. The integrated strain gauge according to claim 4 or 5, characterized in that: At least one second strain unit may be disposed between the inclined strain unit and at least one first strain unit.

7. The integrated strain gauge according to claim 3, characterized in that: The first strain units are arranged in multiple rows in the second direction, and the first strain units in the same row are arranged at equal intervals and symmetrically with respect to the second direction; and the projections of the first strain units in different rows in the first direction are the same.

8. The integrated strain gauge according to claim 3 or 7, characterized in that: The sensitive grid axis of the first strain unit located at both ends of the first direction is parallel to or perpendicular to the first direction; in the case where there is the first strain unit located between the two ends of the first direction, the sensitive grid axis of the first strain unit located between the two ends of the first direction is perpendicular to the first direction.

9. The integrated strain gauge according to claim 1, characterized in that: The strain unit groups are distributed on the substrate to form an L-shape or an I-shape.

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 six first strain units and two second strain units, the six first strain units are arranged in two rows parallel to the first direction, and three are arranged in each row at equal intervals; the two second strain units are distributed along the second direction at intervals; wherein the first strain unit located in the middle of each row is arranged in parallel with the two second strain units; at least the sensitive grid axial directions of the first strain units located at both ends of the first direction in each row are the same and parallel or perpendicular to the first direction; the first direction is perpendicular to the second direction; 2) The strain unit group includes six first strain units and two second strain units, the six first strain units are arranged in two rows parallel to the first direction, and three are arranged in each row at equal intervals; the two second strain units are symmetrically arranged relative to the second direction, and the angles between the sensitive grid axes of the two second strain units and the second direction are respectively between 0 and 75 degrees; wherein the symmetry axes of the two second strain units are collinear with the symmetry axes of the three first strain units in each row; the first direction is perpendicular to the second direction; 3) The strain unit group includes three first strain units and four second strain units, the three first strain units are arranged in a row at equal intervals along the first direction, and the sensitive grids of the first strain units at both ends have the same axial direction; the four second strain units are distributed at intervals along the second direction, and are arranged in parallel with the first strain unit in the middle; wherein the angle between the axial direction of the sensitive grid of one of the four second strain units and the second direction is between 0 and 75 degrees; the first direction is perpendicular to the second direction; 4) The strain unit group includes three first strain units and five second strain units, the three first strain units are arranged in a row at equal intervals along the first direction, and the sensitive grids of at least the first strain units at both ends have the same axial direction; the five second strain units are distributed at intervals along the second direction, and are arranged in parallel with the first strain unit located in the middle; wherein two of the five second strain units are symmetrically inclined relative to the second direction, and the angle between the axis of symmetry and the second direction is between 0 and 75 degrees; the sensitive grids of three of the five second strain units have the same axial direction as the second direction; the first direction is perpendicular to the second direction; 5) The strain unit group includes three first strain units and three second strain units, the three first strain units are arranged in a row at equal intervals along the first direction, and the sensitive grids of at least the first strain units at both ends have the same axial direction; the three second strain units are distributed at intervals along the second direction, and are arranged in parallel with the first strain unit located in the middle; wherein two of the three second strain units are symmetrically inclined relative to the second direction, and the angle between the axis of symmetry and the second direction is between 0 and 75 degrees; the sensitive grid of one of the three second strain units has the same axial direction as the second direction; the first direction is perpendicular to the second direction; 6) The strain unit group includes three first strain units and two second strain units, the three first strain units are arranged in a row at equal intervals along the first direction, and the sensitive grid axial directions of at least the first strain units at the two ends are in the same direction; the two second strain units are distributed at intervals along the second direction, and are arranged in parallel with the first strain unit in the middle; wherein the angle between the sensitive grid axial direction of one of the two second strain units and the second direction is between 0 and 75 degrees, and the sensitive grid axial direction of the other of the two second strain units is in the same direction as the second direction; the first direction is perpendicular to the second direction; 7) The strain unit group includes three first strain units and one second strain unit, the three first strain units are arranged in a row at equal intervals along a first direction, and the sensitive grids of the first strain units at both ends have the same axial direction; the second strain units are distributed along a second direction and are arranged in parallel with the first strain unit in the middle; the first direction is perpendicular to the second direction; 8) The strain unit group includes two first strain units and one second strain unit, the two first strain units are arranged at intervals along the first direction, and the sensitive grids of the two first strain units have the same axial direction; the second strain units are distributed along the second direction and are located on one side of the two first strain units in the second direction; wherein no strain unit is arranged between the two first strain units, and the second strain unit is located on the symmetry axis between the two first strain units; the first direction is perpendicular to the second direction; 9) The strain unit group includes two first strain units and two second strain units, the two first strain units are arranged at intervals along the first direction, and the sensitive grids of the two first strain units have the same axial direction; the two second strain units are arranged in parallel and at intervals along the second direction, and are located on one side of the two first strain units in the second direction; wherein each second strain unit is located symmetrically between the two first strain units; the first direction is perpendicular to the second direction; 10) The strain unit group includes three first strain units and three second strain units, the three first strain units are arranged in a row at equal intervals along a first direction, and the sensitive grids of the first strain units have the same axial direction; the three second strain units are arranged in parallel with the first strain unit in the middle along the second direction; wherein the three second strain units are spaced apart; and the first direction is perpendicular to the second direction; 11) The strain unit group includes five first strain units and one second strain unit, the five first strain units are distributed in two rows along the second direction, two are arranged at intervals in the first row along the first direction, and three are arranged at intervals in the second row along the first direction, and the sensitive grids of the first strain units have the same axial direction; the second strain unit is arranged in parallel with the first strain unit located in the middle along the second direction; wherein the first direction is perpendicular to the second direction.

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