A torque sensor

Abstract

The present application relates to the technical field of sensor, and discloses a torque sensor, wherein the mounting table is protruded from the structural beam, the control board is arranged on the protruded side of the mounting table, and the interval is formed between the control board and the structural beam, so that the control board can avoid directly contacting the structural beam or occupying the elastic deformation space of the structural beam. The flexible potting body is filled between the control board and the structural beam and covers the strain gauge and at least part of the area of the control board, so that the control board, the strain gauge and the connecting wire harness can be sealed and buffered, and the influence of humidity, dust, impact and vibration on the electronic components can be reduced. Since the flexible potting body can deform with the structural beam, the constraint of the potting structure on the elastic deformation of the structural beam can be reduced, the structural beam can keep the corresponding strain response under the action of the measured torque, and the compactness, the detection sensitivity and the long-term working reliability of the torque sensor can be considered.

Description

Technical Field

[0001] This invention relates to the field of sensor technology, and more specifically to a torque sensor. Background Technology

[0002] A torque sensor is a measuring element used to detect the torque applied to rotating parts, and it is widely used in industrial robots, precision transmission equipment, and automated control equipment. A torque sensor typically includes an elastic body, a strain gauge mounted on the elastic body, and a control board electrically connected to the strain gauge. Under the action of torque, the elastic body undergoes elastic deformation. The strain gauge converts the strain of the elastic body into an electrical signal, and the control board acquires and processes this electrical signal to obtain the corresponding torque detection result.

[0003] In existing technologies, some torque sensors employ a front-mounted structure, where the strain gauge is attached to the front of the structural beam of the elastic body, and the control board is positioned on the same end face of the elastic body. This front-mounted structure shortens the connection distance between the strain gauge and the control board and helps reduce the axial dimension of the torque sensor. However, with the structural beam, strain gauge, connecting harness, and control board all concentrated on the end face of the elastic body, the limited installation space makes it difficult to simultaneously meet the requirements for stable installation of the control board, arrangement of the connecting harness, and elastic deformation of the structural beam. When the control board lacks independent support, it easily occupies the deformation space of the structural beam and may shift under assembly, vibration, or impact, causing loose connecting harnesses, damaged solder joints, or unstable signal transmission.

[0004] To protect the control board, strain gauges, and connecting wiring harnesses, related technologies typically use protective covers on the end faces of torque sensors or encapsulate them with potting compound. Using protective covers increases the axial dimensions and number of components of the torque sensor, making it difficult to install in confined spaces such as robot joints. Direct potting, without structures to support the control board and assist in potting molding, can cause the control board and connecting wiring harness to move during the potting process, and the thickness and surface shape of the potting layer are difficult to maintain consistently, affecting the assembly consistency of the torque sensor.

[0005] Furthermore, after curing, the potting material forms a connection with the structural beam, strain gauge, and control plate. If the cured potting material has high stiffness, high shrinkage, or uneven distribution, it may impose additional constraints on the elastic deformation of the structural beam, altering its strain state under torque and thus affecting the detection sensitivity and accuracy of the torque sensor. Differences in thermal expansion properties between the potting material and the elastomer, strain gauge, and control plate may also generate additional stress during temperature changes, causing zero-point drift in the output.

[0006] Therefore, existing front-mounted torque sensors struggle to maintain a compact overall structure while ensuring stable installation of the control board, sealing and protection of strain gauges and connecting harnesses, and elastic deformation of structural beams. The ease of assembly, environmental adaptability, and long-term reliability of torque sensors still need improvement. Summary of the Invention

[0007] This invention provides a torque sensor to solve the problem that in the prior art, torque sensors are difficult to balance the stable installation of the control board, the potting protection of strain gauges and connecting wire harnesses, and the elastic deformation of structural beams within a limited end face space, which affects the detection sensitivity, assembly convenience, and long-term working reliability of the torque sensor.

[0008] This invention provides a torque sensor, comprising: a sensor body, multiple strain gauges, multiple mounting platforms, a control board, and a flexible potting body; the sensor body includes a force-bearing portion, a fixing portion spaced apart on the outer periphery of the force-bearing portion, and multiple structural beams connecting the force-bearing portion and the fixing portion, wherein a potting area is formed between the force-bearing portion and the fixing portion; the multiple strain gauges are respectively attached to one side of the multiple structural beams; the multiple mounting platforms are spaced apart along the circumference of the force-bearing portion in the potting area and spaced apart from the structural beams, the mounting platforms protruding from one side of the structural beams; the control board is mounted and fixed to the protruding side of the multiple mounting platforms, such that the control board is spaced apart from the multiple structural beams, and the control board is electrically connected to the multiple strain gauges; the flexible potting body is formed by curing a flexible potting material in the potting area, the flexible potting body at least fills the space between the control board and the multiple structural beams, and covers at least a portion of the multiple strain gauges and the control board, the flexible potting body deforming with the structural beams.

[0009] Beneficial effects: This invention, by setting mounting platforms protruding from the structural beam and mounting the control board on one side of the protruding platform, creates a gap between the control board and the structural beam, preventing the control board from directly contacting the structural beam or occupying the elastic deformation space of the structural beam. The mounting platforms provide stable mounting support for the control board and support the control board and flexible potting material during the potting process. The flexible potting compound fills the space between the control board and the structural beam and covers at least a portion of the strain gauge and control board, providing sealing and buffering protection for the control board, strain gauge, and connecting wiring harness, reducing the impact of moisture, dust, impact, and vibration on electronic components. Because the flexible potting compound can deform with the structural beam, it reduces the constraint of the potting structure on the elastic deformation of the structural beam, allowing the structural beam to maintain a corresponding strain response under the measured torque, thus balancing the structural compactness, detection sensitivity, and long-term operational reliability of the torque sensor.

[0010] According to some embodiments of the present invention, the mounting platform is connected to the fixing part, the mounting platform and the force-bearing part are spaced apart, and the plurality of mounting platforms are provided with connection holes. The control plate is fixed to the plurality of mounting platforms by fasteners passing through the connection holes. The control plate is provided with glue leakage holes, which penetrate the glue-filling areas on both sides of the structural beam.

[0011] Beneficial effects: The mounting platform, connected to the fixed part and spaced apart from the load-bearing part, allows the load of the mounting platform and control board to be mainly transferred to the fixed part, reducing the impact of the mounting platform and control board on the strain state of the load-bearing part and structural beam. The control board is connected to multiple mounting platforms via fasteners, improving the stability of the control board installation and facilitating its assembly and disassembly. During potting, the flexible potting material can flow through the leakage holes between the potting areas on both sides of the control board and the front and back of the structural beam, ensuring sufficient filling of the potting area and reducing problems such as localized insufficient potting, air pockets, or uneven potting thickness.

[0012] According to some embodiments of the present invention, a plurality of mounting platforms are integrally formed with the fixing part, an installation interval is formed between the control plate and the structural beam, and the strain gauge and connecting wire harness are disposed within the installation interval.

[0013] Beneficial effects: The integrated molding of the mounting platform and fixing unit reduces the number of parts and installation steps, while improving the positioning accuracy, structural strength, and manufacturing consistency of the mounting platform. The installation gap formed between the control board and the structural beam can accommodate strain gauges and connecting harnesses, preventing the control board from compressing the strain gauges or connecting harnesses, and facilitating the electrical connection between the strain gauges and the control board. After the flexible potting material is filled into the installation gap, it can also fix and protect the strain gauges and connecting harnesses located within the installation gap.

[0014] According to some embodiments of the present invention, the height of the support surface of the mounting platform protruding relative to the structural beam is 2-4 mm along a direction perpendicular to the end face of the sensor body.

[0015] Beneficial effects: The support surface of the mounting platform protrudes 2mm to 4mm relative to the structural beam, creating an installation gap between the control board and the structural beam that meets the requirements for strain gauge installation, wiring harness arrangement, and flexible potting material flow. This height range reduces the possibility of interference between the control board and strain gauges, wiring harnesses, or structural beams, while also preventing excessive mounting platform height from increasing the axial dimension of the torque sensor, thus facilitating the miniaturization and integrated installation of the torque sensor.

[0016] According to some embodiments of the present invention, the control board is annular and surrounds the force-bearing part, and the control board is provided with a communication interface for communicating with external devices, the communication interface being at least partially exposed in the flexible potting body.

[0017] Beneficial effects: The annular control board can be arranged using the annular space between the force-bearing part and the fixed part. Without obstructing the installation position of the force-bearing part or interfering with the deformation of the structural beams, the control board can be connected to multiple strain gauges mounted on different structural beams, improving the utilization rate of the sensor body's end face space. The communication interface is at least partially exposed within the flexible potting compound, facilitating connection between the torque sensor and external devices and the transmission of detection signals. Simultaneously, the flexible potting compound protects the area of ​​the control board other than the communication interface.

[0018] According to some embodiments of the present invention, the elastic modulus of the flexible potting body is less than that of the structural beam, and the flexible potting body also covers the connecting wire harness between the strain gauge and the control board.

[0019] Beneficial effects: The elastic modulus of the flexible potting compound is lower than that of the structural beam, allowing the flexible potting compound to deform accordingly when the structural beam undergoes elastic deformation. This reduces the additional stiffness and deformation constraints imposed by the flexible potting compound on the structural beam, thus lowering the impact of the potting structure on detection sensitivity. The flexible potting compound covering the connecting wire harness can restrict the relative movement of the connecting wire harness and its welding positions during vibration or thermal expansion and contraction, reducing the risk of connecting wire harness loosening, solder joint fatigue, or unstable signal transmission.

[0020] According to some embodiments of the present invention, the number of structural beams is four, and the four structural beams are evenly and symmetrically arranged around the stress-bearing part. The strain gauges on the four sets of structural beams are electrically connected to form a full-bridge circuit.

[0021] Beneficial effects: The four structural beams are evenly and symmetrically arranged around the stress-bearing part, allowing the measured torque to be uniformly transmitted among the multiple structural beams, reducing the impact of eccentric loads or local stress concentrations on the test results. The strain gauges installed on the four structural beams are electrically connected to form a full-bridge circuit, which can combine and output strain signals generated by different structural beams, improving the torque detection sensitivity. It can also compensate for signals generated by temperature changes and some non-target direction loads, improving the accuracy and stability of the torque detection results.

[0022] According to some embodiments of the present invention, the strain gauge is disposed in the central region of the structural beam along the length direction of the corresponding structural beam; The mounting platform and the structural beam are alternately arranged within the glue-filling area.

[0023] Beneficial effects: The strain gauges are positioned along the length of the structural beam in its central region, which facilitates the detection of the main strain generated under torque, improving the effectiveness of the strain signal. The alternating placement of the mounting platform and structural beam within the potting area fully utilizes the circumferential space between the stressed and fixed parts, and staggers the support position of the control plate from the strain detection position of the structural beam, reducing interference from the mounting platform and control plate on the elastic deformation of the structural beam.

[0024] According to some embodiments of the present invention, the load-bearing part, the plurality of structural beams, the plurality of mounting platforms and the fixing part are integrally formed from high-strength stainless steel; The force-bearing part has a central hole, a plurality of first mounting holes spaced around the central hole, and a positioning pin adjacent to the central hole. The fixing part has a plurality of second mounting holes for connecting the bearing and a plurality of third mounting holes for connecting the load end in the circumferential direction.

[0025] Beneficial effects: The load-bearing part, structural beam, mounting platform, and fixing part are integrally machined from high-strength stainless steel, which reduces assembly connection points and assembly errors, and improves the overall rigidity, structural strength, and dimensional consistency of the sensor body. The first mounting hole and locating pin facilitate the connection and positioning of the load-bearing part with the rotating component to be measured; the second mounting hole facilitates the connection of the fixing part with the bearing; and the third mounting hole facilitates the connection of the fixing part with the load end, thereby improving the installation efficiency and accuracy of the torque sensor.

[0026] According to some embodiments of the present invention, the connection positions between the structural beam and the force-bearing part and the fixing part are respectively provided with transition fillets or chamfers.

[0027] Beneficial effects: Setting transition fillets or chamfers at the connection points between the structural beam and the load-bearing and fixed parts can make the transition between the structural beam and the load-bearing and fixed parts smooth, reduce stress concentration at the connection points, prevent cracks or fatigue damage at the connection points when the structural beam is repeatedly subjected to torque loads, and improve the load-bearing capacity and operational reliability of the sensor body. Attached Figure Description

[0028] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0029] Figure 1 This is a front axial view of a torque sensor provided in some embodiments of the present invention; Figure 2This is a reverse axial view of a torque sensor provided in some embodiments of the present invention; Figure 3 This is a front axial view of a torque sensor with a control board mounted, provided in some embodiments of the present invention. Figure 4 This is a front axial view of a torque sensor filled with a flexible seal provided in some embodiments of the present invention.

[0030] Explanation of reference numerals in the attached figures: 100. Sensor body; 110. Fixing part; 111. Second mounting hole; 112. Third mounting hole; 120. Force-bearing part; 121. Center hole; 122. First mounting hole; 123. Positioning pin; 130. Structural beam; 140. Potting area; 200. Strain gauge; 300. Mounting platform; 310. Connection hole; 400. Control board; 410. Leakage hole; 420. Communication interface; 500. Flexible potting compound. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] Reference Figures 1 to 4 As shown, according to an embodiment of the present invention, a torque sensor is provided, which includes a sensor body 100, a plurality of strain gauges 200, a plurality of mounting platforms 300, a control board 400, and a flexible potting body 500.

[0033] like Figure 1 and Figure 2 As shown, the sensor body 100 includes a force-receiving part 120, a fixing part 110, and a plurality of structural beams 130 connecting the force-receiving part 120 and the fixing part 110. The force-receiving part 120 is disposed inside the fixing part 110 and spaced apart from the fixing part 110, and the force-receiving part 120 and the fixing part 110 are arranged coaxially. The plurality of structural beams 130 are disposed between the force-receiving part 120 and the fixing part 110 to connect the force-receiving part 120 and the fixing part 110. The area between the force-receiving part 120, the fixing part 110, and the adjacent structural beams 130 forms a potting area 140.

[0034] In one embodiment, the force-receiving part 120 is a central platform located at the center of the sensor body 100, and the fixing part 110 is an outer ring spaced around the outer periphery of the central platform. The central platform, multiple structural beams 130, and the outer ring form a concentric integral structure. The central platform is suspended relative to the outer ring by the multiple structural beams 130, so that the torque acting between the central platform and the outer ring can be transmitted through the multiple structural beams 130.

[0035] Specifically, the force-bearing part 120 includes a polygonal platform located on the front of the sensor body 100 and an annular body located on the back of the polygonal platform. The polygonal platform may be an octagon, and multiple structural beams 130 are respectively connected between the polygonal platform or the annular body and the fixing part 110, and together support the force-bearing part 120.

[0036] Reference Figure 1 As shown, the force-receiving part 120 has a central hole 121, a plurality of first mounting holes 122 spaced around the central hole 121, and a positioning pin 123 adjacent to the central hole 121. The plurality of first mounting holes 122 are used to fix the force-receiving part 120 to the robot flex wheel or other rotating parts to be tested, and the positioning pin 123 is used to perform circumferential positioning of the force-receiving part 120 and the rotating parts to be tested during the assembly process, thereby improving the installation accuracy of the torque sensor.

[0037] The fixing part 110 has an annular structure with an unequal cross-section. The fixing part 110 has multiple second mounting holes 111 and multiple third mounting holes 112 along its circumference. The second mounting holes 111 are used to connect the fixing part 110 to a roller bearing or other support component, and the third mounting holes 112 are used to connect the fixing part 110 to the load end. Through the first mounting holes 122, second mounting holes 111, and third mounting holes 112, the torque sensor can be installed between the rotating component to be measured, the bearing, and the load end.

[0038] In one embodiment, the load-bearing part 120, multiple structural beams 130, multiple mounting platforms 300, and fixing part 110 are integrally formed from high-strength stainless steel. Specifically, precipitation-hardening stainless steel with high strength and good elasticity can be used. The integrally formed structure reduces assembly connections and assembly errors between the load-bearing part 120, structural beams 130, and fixing part 110, thereby improving the structural strength, rigidity, and dimensional consistency of the sensor body 100.

[0039] Multiple structural beams 130 are spaced apart around the central axis of the load-bearing part 120. In a preferred embodiment, there are four structural beams 130, which are evenly and symmetrically arranged around the load-bearing part 120. The four structural beams 130 jointly transmit the torque acting between the load-bearing part 120 and the fixing part 110, so that the torque load is evenly distributed among the multiple structural beams 130, reducing the influence of eccentric loads or local stress concentrations on the test results.

[0040] In one specific embodiment, the structural beam 130 has a thickness of 1.8 mm and a width of 12 mm. The thickness and width of the structural beam 130 are determined based on the rated load, detection sensitivity, and structural strength requirements of the torque sensor. These dimensions enable the structural beam 130 to generate elastic strain that can be effectively detected by the strain gauge 200 when subjected to the target torque, while preventing the stress in the structural beam 130 from exceeding the material's allowable range.

[0041] The structural beam 130 is provided with transition fillets or chamfers at the connection points with the load-bearing part 120 and the fixed part 110, so that the structural beam 130 can smoothly transition with the load-bearing part 120 and the fixed part 110. By providing transition fillets or chamfers, the stress concentration at the root of the structural beam 130 can be reduced, and the possibility of cracks or fatigue damage at the connection points when the structural beam 130 is subjected to repeated torsional loads can be reduced.

[0042] Multiple strain gauges 200 are respectively attached to one side of multiple structural beams 130. In this embodiment, the strain gauges 200 are attached to the side of the structural beam 130 facing the control plate 400, forming a front-facing patch structure. The strain gauges 200 are arranged along the length direction of the corresponding structural beam 130 in the central region of the structural beam 130, which is the main strain region or the maximum strain region when the structural beam 130 is subjected to torque.

[0043] Placing the strain gauge 200 in the central region of the structural beam 130 allows it to fully sense the strain generated in the beam under torque, thus improving the amplitude and effectiveness of the strain signal. The strain gauge 200 can be a resistance strain gauge 200, used to convert the mechanical strain of the structural beam 130 into a resistance change signal.

[0044] In one embodiment, a strain gauge 200 is provided on each of the multiple structural beams 130, and the four strain gauges 200 on the four structural beams 130 are electrically connected to form a Wheatstone full-bridge circuit. The full-bridge circuit can combine the tensile strain and compressive strain generated by different structural beams 130 into a torque detection signal, thereby improving the torque detection sensitivity and compensating for common-mode signals generated by temperature changes and some non-target direction loads.

[0045] Multiple mounting platforms 300 are disposed in the glue-filling area 140 between the force-bearing part 120 and the fixing part 110, and are distributed at intervals along the circumference of the force-bearing part 120. The mounting platforms 300 and the structural beams 130 are spaced apart, and the mounting platforms 300 and the structural beams 130 are arranged alternately along the circumference of the force-bearing part 120. Thus, the mounting platforms 300 are used to support the control plate 400, and the structural beams 130 are used to transmit torque and generate strain detection, and the two are spatially offset from each other.

[0046] In one specific embodiment, there are four mounting platforms 300, which are respectively disposed between two adjacent structural beams 130. All mounting platforms 300 are connected to the fixing part 110 and are spaced apart from the load-bearing part 120 and the adjacent structural beams 130. The mounting platforms 300 are not directly connected to the load-bearing part 120 and the structural beams 130, so that the load borne by the control plate 400 and the mounting platforms 300 is mainly transferred to the fixing part 110, reducing the influence of the mounting platforms 300 and the control plate 400 on the strain state of the load-bearing part 120 and the structural beams 130.

[0047] Multiple mounting platforms 300 can be integrally formed with the fixing part 110. By integrally forming the mounting platforms 300 with the fixing part 110, the assembly process of the mounting platforms 300 can be reduced, the height consistency and positional accuracy of the support surfaces of each mounting platform 300 can be improved, and the stability of the control board 400 after installation can be improved.

[0048] The mounting platform 300 has a support surface on the side facing the control panel 400, which protrudes from the side of the structural beam 130 where the strain gauge 200 is attached. The support surfaces of multiple mounting platforms 300 together form a mounting plane for supporting the control panel 400. The control panel 400 is mounted on the support surfaces of multiple mounting platforms 300 and is spaced apart from multiple structural beams 130.

[0049] Along a direction perpendicular to the end face of the sensor body 100, the support surface of the mounting platform 300 protrudes 2mm to 4mm above the front face of the structural beam 130. In a preferred embodiment, this protrusion is 2mm. This height difference creates a mounting gap between the control plate 400 and the structural beam 130, allowing the strain gauge 200 and the connecting harness between the strain gauge 200 and the control plate 400 to be accommodated within the mounting gap.

[0050] When the protrusion height is too small, the control board 400 may interfere with the strain gauge 200, the connecting harness, or the structural beam 130, and the connecting harness will also lack sufficient space for arrangement. When the protrusion height is too large, it will increase the axial dimension of the torque sensor. Therefore, setting the protrusion height of the mounting platform 300 to 2mm to 4mm can balance the installation space for the strain gauge 200 and the connecting harness with the compactness of the torque sensor.

[0051] Reference Figure 2 and Figure 3 As shown, each of the multiple mounting platforms 300 is provided with a connection hole 310, and the control plate 400 is provided with a fastener through hole corresponding to the connection hole 310. When installing the control plate 400, the control plate 400 is placed on the support surface of the multiple mounting platforms 300, the fastener through hole is aligned with the corresponding connection hole 310, and the fastener is passed through the control plate 400 and connected to the connection hole 310, thereby fixing the control plate 400 to the multiple mounting platforms 300.

[0052] In one embodiment, the connection hole 310 is a threaded hole, and the fastener is a screw. The control board 400 is fixed to the mounting platform 300 by multiple screws, which not only improves the installation stability of the control board 400, but also facilitates the inspection and debugging of the control board 400, strain gauge 200 and connecting harness before potting.

[0053] The control plate 400 is annular and surrounds the force-receiving part 120. A clearance hole is provided in the center of the control plate 400 to avoid obstructing the center hole 121, the first mounting hole 122, and the positioning pin 123 of the force-receiving part 120. The annular control plate 400 can be arranged using the annular space between the force-receiving part 120 and the fixing part 110, improving the utilization rate of the end face space of the sensor body 100.

[0054] The control board 400 is electrically connected to multiple strain gauges 200, and is used to supply power to the strain gauges 200, acquire the electrical signals output by the multiple strain gauges 200, and determine the torque to be measured based on the electrical signals output by the multiple strain gauges 200. The connection harness of the strain gauges 200 extends from the corresponding structural beam 130 to the control board 400, and is connected to the control board 400 within the installation interval between the control board 400 and the structural beam 130.

[0055] The control board 400 is provided with a communication interface 420, which is used to communicate with external control devices, data acquisition devices, or robot controllers to output torque detection data to external devices. The communication interface 420 is located on the side of the control board 400 near the fixing part 110 and extends at least partially out of the subsequently formed flexible potting body 500 to facilitate the connection of external connectors with the communication interface 420.

[0056] The control panel 400 also has one or more glue leakage holes 410. The glue leakage holes 410 penetrate the control panel 400 along its thickness direction and correspond to the glue filling area 140. The glue leakage holes 410 are used to allow flexible potting material to pass through during the glue filling process, so that the glue filling spaces located on the front and back sides of the control panel 400 are interconnected, and the flexible potting material can flow into the glue filling area 140 located on the front and back sides of the structural beam 130.

[0057] In one embodiment, a plurality of injection holes 410 are spaced apart circumferentially along the control plate 400. During injection, the flexible potting material can flow through the injection holes 410 at different locations to the space between the control plate 400 and the structural beam 130, and continue into the area between the force-bearing part 120, the fixing part 110, and the plurality of structural beams 130. This improves the uniformity of the flow of the flexible potting material within the injection area 140, reducing the possibility of insufficient potting material, cavitation, or localized insufficient potting thickness below the control plate 400.

[0058] Before installing the control board 400, first attach multiple strain gauges 200 to predetermined positions on the corresponding structural beams 130, and guide the connecting wires of the strain gauges 200 to the corresponding mounting platforms 300. Then, place the annular control board 400 on the supporting surfaces of the mounting platforms 300 and secure it with fasteners. After securing the control board 400, weld or connect the connecting wires of the strain gauges 200 to the control board 400.

[0059] After the control board 400 is installed, an installation gap is formed between the control board 400 and the multiple structural beams 130. The strain gauges 200, connecting harnesses, and the welding positions between the connecting harnesses and the control board 400 are all located within the installation gap. The control board 400 is stably supported by multiple mounting platforms 300, and will not directly compress the strain gauges 200 and connecting harnesses, nor will it occupy the elastic deformation space of the structural beams 130.

[0060] After the strain gauge 200 and control board 400 are installed, the sensor body 100 is potted with adhesive using a potting fixture. The potting fixture is used to seal the predetermined boundary of the potting area 140 and define the shape of the flexible potting body 500 after curing. The communication interface 420 can be protected with a shielding component before potting to prevent the flexible potting material from entering the communication interface 420.

[0061] A fluid, flexible potting material is injected into the potting area 140 between the stress-bearing part 120 and the fixing part 110. Supported and guided by the mounting platform 300 and the control plate 400, the flexible potting material flows between the control plate 400 and the structural beam 130, and flows through the drainage holes 410 on the control plate 400 between the potting spaces on both sides of the control plate 400. The flexible potting material further surrounds the multiple strain gauges 200, the connecting harnesses, the welding positions, and at least a portion of the control plate 400.

[0062] The flexible potting material fills the predetermined potting area 140 and then cures to form a flexible potting body 500. The surface of the flexible potting body 500 facing away from the sensor body 100 can be flush with the end face of the sensor body 100, so that the torque sensor forms a relatively flat end face. The communication interface 420 is at least partially exposed in the flexible potting body 500 for connection to external devices.

[0063] In one embodiment, the flexible potting material can be an elastic epoxy potting material, a polyurethane potting material, or a silicone rubber potting material. The elastic modulus of the flexible potting body 500 formed after the flexible potting material has cured is less than the elastic modulus of the structural beam 130, allowing the flexible potting body 500 to deform accordingly when the structural beam 130 undergoes elastic deformation.

[0064] In this embodiment, although the flexible potting compound 500 fills the space between the control plate 400 and the structural beam 130, it does not rigidly lock the structural beam 130. When the structural beam 130 undergoes elastic deformation under the measured torque, the flexible potting compound 500 can undergo corresponding elastic deformation with the structural beam 130, thereby reducing the additional stiffness and deformation constraints formed by the flexible potting compound 500 on the structural beam 130 and reducing the impact of the potting structure on the torque detection sensitivity.

[0065] The flexible potting compound 500 covers at least a portion of the strain gauge 200, the connecting harness, and the control board 400, preventing dust, moisture, and other contaminants from directly contacting the strain gauge 200, solder joints, and control board 400. The flexible potting material can also penetrate the minute gaps between the strain gauge 200, the connecting harness, and the control board 400, reducing the likelihood of moisture repeatedly entering and leaving these gaps during temperature changes.

[0066] After curing, the flexible potting compound 500 forms a three-dimensional connection structure, spatially fixing the connecting wire harness and solder joints. When the torque sensor is subjected to vibration or temperature cycling, the flexible potting compound 500 can limit the relative movement between the connecting wire harness and the control board 400, reducing the risks of solder joint fatigue, connecting wire harness wear, and unstable signal transmission.

[0067] Furthermore, the flexible potting compound 500 can form a buffer layer between the strain gauge 200, the control board 400, and the sensor body 100. When the sensor body 100 is subjected to external impact, the flexible potting compound 500 can absorb part of the impact energy through its own deformation and convert the local concentrated load into a distributed load, reducing the risk of damage to the strain gauge 200, the control board 400, and the solder joints due to impact.

[0068] In an optional embodiment, the flexible potting material is a thermally conductive potting material. The heat generated during operation of the control board 400 can be transferred to the sensor body 100 via the flexible potting body 500, and then dissipated outwards through the sensor body 100. The flexible potting body 500 can also buffer rapid changes in ambient temperature through its own thermal capacity, reducing the impact of sudden temperature changes on the zero point output of the control board 400 and the strain gauge 200.

[0069] In an optional embodiment, the elastic modulus of the flexible potting material can be selected based on the rated load of the torque sensor, the target natural frequency, and the torsional stiffness. By adjusting the elastic modulus of the flexible potting material, the vibration damping and overall operational stability of the torque sensor can be improved while ensuring the sensitivity of strain detection of the structural beam at 130°.

[0070] The working process of the torque sensor is explained below.

[0071] After the torque sensor is installed, the force-receiving part 120 is connected to the rotating component under test, and the fixing part 110 is connected to the bearing and the load end. When the rotating component under test applies torque to the force-receiving part 120, the torque is transmitted from the force-receiving part 120 to multiple structural beams 130, and then through the multiple structural beams 130 to the fixing part 110.

[0072] Multiple structural beams 130 undergo elastic deformation under torque. Strain gauges 200 attached to the structural beams 130 deform along with the structural beams 130, and their resistance values ​​change accordingly. A full-bridge circuit composed of four strain gauges 200 converts the resistance changes of the multiple strain gauges 200 into voltage signals and transmits the voltage signals to the control board 400.

[0073] The control board 400 acquires, amplifies, and processes the voltage signal output by the full-bridge circuit, determines the torque to be measured based on the predetermined correspondence between the torque and the electrical signal, and transmits the torque detection result to an external device through the communication interface 420.

[0074] During the elastic deformation of the structural beam 130, the control plate 400 is supported by the mounting platform 300 spaced apart from the structural beam 130. Therefore, the control plate 400 will not undergo the same displacement as the structural beam 130, nor will it directly press against the structural beam 130. The flexible potting body 500 deforms accordingly with the structural beam 130 through its own flexibility, thereby protecting the strain gauge 200, the connecting harness, and the control plate 400 while allowing the structural beam 130 to maintain an effective strain response.

[0075] In this embodiment, multiple mounting platforms 300 protruding from the structural beam 130 are provided on the fixing part 110, and the control board 400 is mounted on the multiple mounting platforms 300, so that an installation interval for mounting the strain gauge 200 and the connecting wire harness is formed between the control board 400 and the structural beam 130. By providing glue leakage holes 410 on the control board 400, the flexible potting material can fully fill the potting areas 140 on both sides of the control board 400 and the front and back sides of the structural beam 130. The control board 400, strain gauge 200 and connecting wire harness are potted and protected by the flexible potting body 500, which deforms with the structural beam 130. Therefore, while maintaining the compact structure of the torque sensor, the stable installation of the control board 400, the sealed protection of electronic components and the effective elastic deformation of the structural beam 130 can be taken into account, thereby improving the detection sensitivity, assembly convenience, environmental adaptability and long-term working reliability of the torque sensor.

[0076] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A torque sensor, characterized in that, include: The sensor body (100) includes a force-bearing part (120), a fixing part (110) spaced apart on the outer periphery of the force-bearing part (120), and a plurality of structural beams (130) connecting the force-bearing part (120) and the fixing part (110), and an adhesive-filling area (140) is formed between the force-bearing part (120) and the fixing part (110). Multiple strain gauges (200) are respectively attached to one side of multiple structural beams (130); Multiple mounting platforms (300) are spaced apart in the glue-filling area (140) along the circumference of the force-bearing part (120) and spaced apart from the structural beam (130). The mounting platforms (300) protrude from one side of the structural beam (130). A control board (400) is mounted and fixed on the protruding side of a plurality of mounting platforms (300), such that the control board (400) is spaced apart from the plurality of structural beams (130), and the control board (400) is electrically connected to the plurality of strain gauges (200). A flexible potting body (500) is formed by curing a flexible potting material within the potting area (140). The flexible potting body (500) fills at least between the control plate (400) and the plurality of structural beams (130), and covers at least a portion of the plurality of strain gauges (200) and the control plate (400). The flexible potting body (500) deforms with the structural beams (130). The mounting platform (300) is connected to the fixing part (110), and the mounting platform (300) and the force-bearing part (120) are spaced apart. Each of the mounting platforms (300) is provided with a connection hole (310). The control plate (400) is fixed to the mounting platforms (300) by fasteners passing through the connection holes (310). The control plate (400) is provided with a glue leakage hole (410), which penetrates the glue-filling area (140) on both sides of the structural beam (130). Multiple mounting platforms (300) are integrally formed with the fixing part (110), and an installation interval is formed between the control plate (400) and the structural beam (130). The strain gauge (200) and the connecting wire harness are located within the installation interval. Along the direction perpendicular to the end face of the sensor body (100), the height of the support surface of the mounting platform (300) protruding relative to the structural beam (130) is 2-4 mm.

2. The torque sensor according to claim 1, characterized in that, The control board (400) is ring-shaped and surrounds the force-bearing part (120). The control board (400) is provided with a communication interface (420) for communicating with external devices. The communication interface (420) is at least partially exposed in the flexible potting body (500).

3. The torque sensor according to claim 1, characterized in that, The elastic modulus of the flexible potting body (500) is less than that of the structural beam (130), and the flexible potting body (500) also covers the connecting wire harness between the strain gauge (200) and the control board (400).

4. The torque sensor according to claim 1, characterized in that, The number of structural beams (130) is four. The four structural beams (130) are evenly and symmetrically arranged around the force-bearing part (120). The strain gauges (200) on the four sets of structural beams (130) are electrically connected to form a full-bridge circuit.

5. The torque sensor according to claim 4, characterized in that, The strain gauge (200) is disposed in the central region of the structural beam (130) along the length direction of the corresponding structural beam (130); The mounting platform (300) and the structural beam (130) are alternately arranged within the glue-filling area (140).

6. The torque sensor according to claim 5, characterized in that, The load-bearing part (120), the plurality of structural beams (130), the plurality of mounting platforms (300) and the fixing part (110) are integrally formed from high-strength stainless steel; The force-bearing part (120) is provided with a central hole (121), a plurality of first mounting holes (122) spaced around the central hole (121) and a positioning pin (123) adjacent to the central hole (121). The fixing part (110) is provided with a plurality of second mounting holes (111) for connecting the bearing and a plurality of third mounting holes (112) for connecting the load end in the circumferential direction.

7. The torque sensor according to claim 1, characterized in that, The connection points between the structural beam (130) and the force-bearing part (120) and the fixing part (110) are respectively provided with transition fillets or chamfers.

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