Robotic arm, robot arm joint and torque detection device

Abstract

The present invention relates to a mechanical arm, a mechanical arm joint and a torque detection device. The mechanical arm is composed of a plurality of mechanical arm joints. The mechanical arm joints include a torque input end, a torque detection device and a torque output end which are connected in sequence and arranged coaxially. The torque detection device includes a main structure and at least one deformable beam. Two opposite sides of the main structure which are perpendicular to its own axis direction are used for fixed connection with the torque input end and the torque output end respectively. The outer edge of the main structure is provided with at least one notch, and a deformable beam is arranged in each notch. The length of the deformable beam corresponds to the circumferential arrangement of the main structure, and the two opposite fixed ends of the deformable beam along its own length are respectively fixedly connected with the main structure. The present invention ensures the rigidity of the torque detection device and improves the positioning accuracy of the mechanical arm without sacrificing the torque measurement performance.

Description

Technical Field

[0001] This invention belongs to the field of detection technology, and specifically relates to a torque detection device for detecting the torque generated on the joints of a robotic arm. Background Technology

[0002] Existing torque detection devices are mostly flange-type, featuring concentric inner and outer flange structures connected to the joint's input and output sides, respectively. The inner and outer flange structures are connected by symmetrically arranged beams, which are configured with different cavities to withstand torque and undergo some deformation. Strain gauges are attached to the deformation areas of the beams, and the torque is detected by a signal processing circuit. To achieve good measurement performance, the beams connecting the inner and outer flange structures need to undergo significant deformation. However, this results in a substantial reduction in the overall stiffness of the torque detection device. If applied to robot joints, this will significantly impact joint stiffness and robotic arm stiffness, reducing the robotic arm's positioning accuracy. Therefore, existing flange-type torque detection devices cannot simultaneously meet the requirements of both measurement performance and stiffness. Summary of the Invention

[0003] The purpose of this invention is to provide a robotic arm, a robotic arm joint, and a torque detection device to solve the problem that existing torque detection devices cannot simultaneously take into account both measurement performance and stiffness.

[0004] To achieve the above objectives, the present invention provides a torque detection device, which includes a main structure and at least one deformable beam; two opposite sides of the main structure along a direction perpendicular to its own axis are respectively fixedly connected to a torque input end and a torque output end;

[0005] The outer edge of the main structure is provided with at least one notch, and each notch is provided with a deformable beam; the length of the deformable beam corresponds to the circumferential direction of the main structure, and the two opposite fixed ends of the deformable beam along its own length are respectively fixedly connected to the main structure.

[0006] In one embodiment, the deformable beam is a centrally symmetrical structure, the deformable beam has a strain zone located between the two fixed ends, and a connection zone is provided between the strain zone and the fixed ends, the width of the connection zone being smaller than the width of the fixed ends and the width of the strain zone.

[0007] In one embodiment, the strain zone has a perforation.

[0008] In one embodiment, the connection area is smoothly connected to the fixed end and the strain area.

[0009] In one embodiment, a reinforcing region is provided between the connecting region and the strain region, the width of the reinforcing region being greater than the width of the strain region and the width of the connecting region, and the reinforcing region being smoothly connected to the strain region and the connecting region.

[0010] In one embodiment, the strain zone has two opposite sides arranged in parallel along its width direction, and the two parallel sides of the strain zone are used to mount strain gauges.

[0011] In one embodiment, the axial direction of the deformable beam is perpendicular to the radial direction of the main structure, so that the deformable beam is only subjected to forces along its own axial direction.

[0012] In one embodiment, there are multiple notches, which are evenly arranged along the circumference of the main structure, and each notch contains a deformable beam.

[0013] In one embodiment, the fixing end and the main structure are connected by a pin or screw, or the fixing end and the main structure are engaged and bonded together with adhesive.

[0014] In one embodiment, when the fixed end and the main structure are connected by a snap-fit ​​connection, the fixed end is provided with a lug, and the notch is provided with hooks that cooperate with the lug on two opposite sides along the circumferential direction.

[0015] In one embodiment, the main structure is a centrally symmetrical structure and has a through central hole.

[0016] In one embodiment, the main structure is a split structure or a one-piece molded structure.

[0017] In one embodiment, the outer edge of the main structure is further provided with a clearance notch, which does not coincide with the recess.

[0018] In one embodiment, there are multiple clearance gaps, which are evenly distributed along the circumference of the main structure.

[0019] In one embodiment, the torque detection device further includes a strain gauge, wherein:

[0020] At least two strain gauges are disposed on the main structure, and at least two other strain gauges are disposed on one of the deformable beams, and the at least two strain gauges on the main structure and the at least two strain gauges on the deformable beams form a Wheatstone bridge;

[0021] Alternatively, the deformable beams may be configured as multiple beams, each of which may be provided with at least two strain gauges, and at least four strain gauges on any two deformable beams may form a Wheatstone bridge.

[0022] Alternatively, the deformable beams may be configured as multiple beams, with at least four strain gauges disposed on the main structure. Each deformable beam may have at least two strain gauges disposed on it, and the at least two strain gauges on each deformable beam and the corresponding at least two strain gauges on the main structure may form a Wheatstone bridge.

[0023] To achieve the above objectives, the present invention also provides a robotic arm joint, which includes a torque input end, a torque output end, and a torque detection device as described in any one of the above. The torque input end, the torque detection device, and the torque output end are connected in sequence and coaxially arranged. From the axial direction of the torque detection device, the two opposite sides of the main structure of the torque detection device are fixedly connected to the torque input end and the torque output end, respectively.

[0024] To achieve the above objectives, the present invention also provides a robotic arm composed of a plurality of the aforementioned robotic arm joints.

[0025] In the robotic arm, robotic arm joint, and torque detection device provided by the present invention, the torque detection device includes: a main structure and at least one deformable beam; the two opposite sides of the main structure along the direction perpendicular to its own axis are respectively fixedly connected to a torque input end and a torque output end; the outer edge of the main structure is provided with at least one notch, and each notch is provided with a deformable beam; the length of the deformable beam corresponds to the circumferential direction of the main structure, and the two opposite fixed ends of the deformable beam along its own length are respectively fixedly connected to the main structure.

[0026] In this configuration, on the one hand, the main structure itself bears the torque as a whole. The main structure is not connected by deformable beams; instead, deformable beams are installed at the recesses on the outer edge of the main structure to sense the torque. However, while deforming, the deformable beams further enhance the stiffness of the torque detection device, making its stiffness the sum of the stiffness of the main structure and the deformable beams, thus achieving high stiffness. On the other hand, because the deformable beams are located at the outer edge of the main structure and can achieve a large amount of deformation, the torque detection device also has good torque measurement performance, ensuring torque detection accuracy. Therefore, the torque detection device of this invention can simultaneously meet the requirements of torque measurement performance and stiffness. Without sacrificing torque measurement performance, it ensures the stiffness of the torque detection device, further ensuring the stiffness of the robotic arm joints and the robotic arm itself, and improving the positioning accuracy of the robotic arm. Furthermore, the torque detection device of this invention has a simple structure, is easy to use and install, and is more conducive to encapsulation, improving oil resistance and sealing during torque detection. Attached Figure Description

[0027] The accompanying drawings are provided to better understand the invention and are not intended to unduly limit the scope of the invention. Wherein:

[0028] Figure 1 This is an exploded view of the torque detection device, torque input end, and torque output end in Embodiment 1 of the present invention;

[0029] Figure 2 This is a front view of the torque detection device in Embodiment 1 of the present invention;

[0030] Figure 3 This is a front view of a deformable beam according to one embodiment of the present invention;

[0031] Figure 4 for Figure 3 Cross-sectional view of the deformable beam along line AA;

[0032] Figure 5 This is a front view of the first part of the main structure and the deformable beam on it in Embodiment 1 of the present invention;

[0033] Figure 6 This is a front view of the first part of the main structure in Embodiment 1 of the present invention;

[0034] Figure 7 This is a front view of the main structure in Embodiment 2 of the present invention;

[0035] Figure 8 This is a front view of the main structure in Embodiment 3 of the present invention;

[0036] Figure 9 This is a front view of the deformable beam in Embodiment 4 of the present invention;

[0037] Figure 10 This is a front view of the deformable beam in Embodiment 5 of the present invention;

[0038] Figure 11 This is a front view of the deformed beam in Embodiment Six of the present invention;

[0039] Figure 12 This is a schematic diagram of the deformable beam in Embodiment 7 of the present invention being connected by screws from the left and right directions;

[0040] Figure 13 This is a schematic diagram of the deformable beam in Embodiment 8 of the present invention being connected by screws from the front and rear directions;

[0041] Figure 14 This is a schematic diagram of the deformable beam connected by pins from top to bottom in Embodiment 9 of the present invention. Detailed Implementation

[0042] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0043] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. As used herein, the singular forms “a,” “an,” and “the” include plural objects unless otherwise expressly indicated. As used herein, the term “or” is generally used to include the meaning of “and / or” unless otherwise expressly indicated. As used herein, the terms “a plurality” and “several” are generally used to include the meaning of “two or more” unless otherwise expressly indicated. Furthermore, the terms “first” and “second” are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as “first” or “second” may explicitly or implicitly include one or at least two of that feature. Further, the terms described herein are not intended to limit the scope of the invention. For example, spatially relative terms—such as “below,” “under,” “down,” “above,” “up,” “horizontal,” “vertical,” etc.—can be used to describe the relationship between one element or feature and another element or feature as shown in the figures. These spatially relative terms are intended to include different positions and orientations of the device in use or operation, other than those shown in the figures. For example, if the device in the figure is flipped, then the element described as “below other elements or features” or “under other elements or features” will then be “above other elements or features” or “on other elements or features.” Thus, the example term “below” can include both above and below positions and orientations. The device may be otherwise oriented (rotated 90 degrees or otherwise), and the spatially relative descriptive terms used herein are interpreted accordingly. Similarly, descriptions of movement along and about various axes include various specific device positions and orientations. Furthermore, the term “comprising” specifies the presence of the described features, steps, operations, elements, and / or components but does not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups. Components described as connected may be electrically or mechanically directly connected, or they may be indirectly connected via one or more intermediate components.

[0044] In this article, "axial" refers to the direction along the axis of the torque detection device or the joint of the robotic arm; "radial" refers to the direction along the cross-section of the torque detection device or the joint of the robotic arm; "circumferential" refers to the direction around the axis of the torque detection device or the joint of the robotic arm; "split structure" refers to mechanical structures that are formed individually or separately; "integral structure" refers to mechanical structures that are formed as a whole or as a single piece; "split connection" refers to mechanical structures that are formed individually or separately and then connected together in a suitable way; "integral connection" refers to mechanical structures that are connected as a whole or as a single piece.

[0045] The core of this invention lies in providing a torque detection device to solve the problems existing in existing flange-type torque detection devices. The torque detection device of this invention can simultaneously meet the requirements of torque measurement performance and stiffness, achieving excellent torque measurement performance while also possessing sufficient stiffness.

[0046] The torque detection device proposed in this invention is mainly applied to robotic arm joints, particularly those of surgical robots. It is important to understand that stiffness is a crucial indicator for robot joints, directly affecting positioning accuracy during use. The torque detection device of this invention can maintain high stiffness while detecting torque, and simultaneously ensure high torque detection accuracy, achieving a balance between the two. Furthermore, it boasts advantages such as simple structure, convenient packaging, and improved resistance to oil contamination and sealing.

[0047] The present application will be further described below with reference to the accompanying drawings and preferred embodiments. In the absence of conflict, the following embodiments and features can complement or combine with each other.

[0048] <Example 1>

[0049] Please refer to Figure 1 and Figure 2 Embodiment 1 of the present invention provides a robotic arm, which is composed of multiple robotic arm joints. The number of robotic arm joints is not particularly limited, such as being greater than, less than or equal to, 6. Each robotic arm joint includes a torque input end 10, a torque detection device 20, and a torque output end 30, which are sequentially connected and coaxially arranged.

[0050] The torque detection device 20 includes a main structure 21 and at least one deformable beam 22. The main structure 21 is located between the torque input end 10 and the torque output end 30, and is fixedly connected to both ends. Two opposite sides of the main structure 21 along a direction perpendicular to its own axis are fixedly connected to the torque input end 10 and the torque output end 30, respectively. See details below. Figure 2 Viewed from the axis perpendicular to the main structure 21, the left and right sides of the main structure 21, as indicated by the dashed box, are connected to the torque input end 10 and the torque output end 30, respectively. Specifically, the left side is connected to the torque input end 10, and the right side is connected to the torque output end 30. The torque input end 10 inputs torque, and the torque output end 30 outputs torque. The torque detection device 20 transmits and detects torque between the torque input end 10 and the torque output end 30.

[0051] The main structure 21 is generally disc-shaped with a suitable geometric shape, such as circular or square, but primarily circular. The main structure 21 is preferably centrally symmetrical and optionally includes a central hole (not labeled), through which related structures or wires on the robotic arm joints can pass. The main structure 21 can be a split structure, specifically composed of a symmetrically arranged first part 211 and a second part 212. The first part 211 and the second part 212 are independently formed and then fixedly connected in a suitable manner to form the main structure 21. In actual use, one side of each of the first part 211 and the second part 212 is fixedly connected to the torque input end 10, and the other side of each is fixedly connected to the torque output section 30. For example, from... Figure 1 and Figure 2 From the perspective of the first part 211 and the second part 212, the left sides are both fixedly connected to the torque input end 10, and the right sides of the first part 211 and the second part 212 are both fixedly connected to the torque output end 30. The connection between the main structure 21 and the torque input end 10 and the torque output end 30 is usually a screw connection. A certain number of mounting holes for screw connections are distributed on the first part 211 and the second part 212, and the number of mounting holes is not specially required.

[0052] The structure of Part 211 and Part 212 is completely identical. For clarity, Part 211 will be used as an example for explanation. The structure of Part 212 can be referred to Part 211.

[0053] refer to Figure 5 and Figure 6 The first part 211 has mounting holes 2111 for connecting to the torque input end 10 and the torque output end 30. At least one recess 213 is provided in the outer edge of the first part 211. The shape and size of the recess 213 are designed to accommodate the entire deformable beam 22. In the illustrated embodiment, the recess 213 is U-shaped. Preferably, the bottom of the recess 213 is rounded. One deformable beam 22 is provided in each recess 213. The deformable beam 22 is positioned on the main structure 21 in a suitable direction. Specifically, the length of the deformable beam 22 corresponds to the circumference of the main structure 21, such that the main force direction of the deformable beam 22 is axial rather than transverse, and the deformable beam 22 is mainly subjected to axial tension or compression. The axial direction of the deformable beam 22 is the length direction, and the transverse direction is the width direction. Furthermore, the two opposite fixed ends of the deformable beam 22 along its own length are fixedly connected to the main structure 21. The fixed connection can be detachable or non-detachable, and no special requirements are placed on the fixed connection method.

[0054] It is understandable that the main structure 21 itself does not need to be connected by the deformable beam 22. That is, the deformable beam 22 is not used to connect the main structure 21, allowing the main structure 21 to bear most of the torque of the robotic arm joint as a whole. Therefore, it has greater rigidity to meet the rigidity requirements of the torque detection device 20. It should also be understood that the deformable beam 22 is installed at the outer edge of the main structure 21, which not only further strengthens the rigidity of the main structure 21, but also achieves greater deformation. Therefore, it also meets the torque measurement performance requirements of the torque detection device 20.

[0055] Therefore, the torque detection device 20 of the present invention does not require an inner and outer flange structure, nor does it require a beam connecting the inner and outer flange structures. Instead, the main body structure 21 acts as a whole to bear the torque, and a deformable beam 22 is installed at the notch 213 on the outer edge of the main body structure 21 to sense the torque. Furthermore, the deformable beam 22, while deforming, further enhances the stiffness of the torque detection device 20. Thus, the stiffness of the torque detection device 20 is the sum of the stiffness of the main body structure 21 and the stiffness of the deformable beam 22, resulting in high stiffness. Moreover, the deformable beam 22, located at the outer edge of the main body structure 21, can itself achieve a large deformation, giving the torque detection device 20 good measurement performance. Therefore, the torque detection device 20 of the present invention can simultaneously meet the requirements of measurement performance and stiffness, ensuring the stiffness of the torque detection device 20 without sacrificing measurement performance, thereby ensuring the joint stiffness of the robotic arm and the stiffness of the robotic arm, and improving the positioning accuracy of the robotic arm.

[0056] The axial direction of the deformable beam 22 is set at a certain angle to the radial direction of the main structure 21, rather than coinciding with it. Preferably, the axial direction of the deformable beam 22 is perpendicular to the radial direction of the main structure 21, so that when the deformable beam 22 is subjected to force, it is basically only subjected to force along its own axial direction (i.e., the length direction) (such as axial tension or axial pressure), thereby further improving the torque detection accuracy and avoiding the influence of forces in other directions on torque detection.

[0057] The deformable beams 22 are preferably multiple, thereby improving the accuracy of torque detection. At least two strain gauges 23 are symmetrically arranged on each deformable beam 22 (e.g., Figure 4(As shown). Multiple deformable beams 22 are preferably evenly arranged along the circumference of the main structure 21. Correspondingly, there are multiple recesses 213, evenly arranged along the circumference of the main structure 21, with one deformable beam 22 disposed in each recess 213. In the illustrated embodiment, there are two deformable beams 22, respectively disposed on the first part 211 and the second part 212, and the two deformable beams 22 are circumferentially offset by 180°. Of course, the number of deformable beams 22 can also be three or more, with all deformable beams 22 offset by a certain angle along the circumference of the main structure 21, preferably by the same angle. The two opposite fixed ends of each deformable beam 22 are fixedly connected to the main structure 21, and each deformable beam 22 undergoes elastic deformation due to external loads (torque).

[0058] The deformable beam 22 and the main structure 21 can be an integral or separate structure. In the illustrated embodiment, the deformable beam 22 and the main structure 21 are connected separately to facilitate the individual fabrication of the deformable beam 22 and the main structure 21, allowing them to be configured with different strengths and / or different moduli of elasticity, thereby better meeting the requirements for measurement performance and stiffness during torque detection. The material strength of the main structure 21 is preferably higher than that of the deformable beam 22, and / or the material modulus of elasticity of the main structure 21 is preferably higher than that of the deformable beam 22. The main structure 21 is preferably made of a high-strength and high-modulus-elastic ...

[0059] The torque detection device 20 may further include strain gauges 23, with at least two strain gauges 23 symmetrically arranged on a deformable beam 22. The strain gauges 23 deform along with the deformable beam 22. The strain gauges 23 display their deformation as a change in their resistance value. The change in resistance value can be used to obtain the change in voltage of the Wheatstone bridge, and measuring the voltage change allows for the measurement of the torque experienced by the robotic arm joint. The strain gauges 23 are typically composed of resistance wires, which are located on a thin load-bearing element, such as one made of an alloy material.

[0060] There are various arrangements of strain gauges 23. In some embodiments of this application, at least two strain gauges 23 are symmetrically arranged on the main structure 21, and at least two other strain gauges 23 are symmetrically arranged on a deformable beam 22, with the at least two strain gauges 23 on the main structure 21 and the at least two strain gauges 23 on the deformable beam 22 forming a Wheatstone bridge. In some embodiments of this application, there are multiple deformable beams 22, with at least two strain gauges 23 symmetrically arranged on each deformable beam 22, and at least four strain gauges 23 on any two deformable beams 22 forming a Wheatstone bridge. In other embodiments of this application, at least four strain gauges 23 are symmetrically arranged in pairs on the main structure 21, with at least two strain gauges 23 symmetrically arranged on each deformable beam 22, and the at least two strain gauges 23 on each deformable beam 22 and the corresponding at least two strain gauges 23 on the main structure 21 forming a Wheatstone bridge. The strain gauges 23 on the main structure 21 are mainly located in non-strain-sensitive areas for use as temperature compensation resistors. It should be understood that the strain gauge 23 on the main structure 21 is used for temperature compensation to eliminate the influence of temperature on torque measurement. Therefore, the strain gauge 23 on the main structure 21 needs to be set in the non-strain sensitive area to eliminate the influence of strain on the temperature compensation resistor.

[0061] The torque detection device 20 may further include a processing unit (not shown) connected to a Wheatstone bridge. This processing unit is used to obtain the torque applied to the joint of the robotic arm based on the electrical signal (such as voltage) output by the Wheatstone bridge. This application does not limit the structure of the processing unit; those skilled in the art can understand its structure based on existing technology. For example, it may be configured as a dedicated integrated circuit (ASIC). The ASIC can process the electrical signal from the Wheatstone bridge by acquiring, amplifying, filtering, and performing analog-to-digital conversion, ultimately obtaining the torque based on the electrical signal. The signal processing circuit board may be mounted on the main structure 21 or at other locations (such as the torque input terminal 10 and the torque output terminal 30). Preferably, the processing unit is directly fixed to the main structure 21 and located between the torque input terminal 10 and the torque output terminal 30, which reduces wiring length and wiring difficulty.

[0062] refer to Figure 3 and Figure 4The deformable beam 22 is preferably a centrally symmetrical structure, meaning it is symmetrical about both its length and width axes. During torque detection, the deformable beam 22 experiences uniform stress and is subjected to axial tension or compression to sense torque, resulting in high torque detection accuracy. Specifically, the deformable beam 22 includes two fixed ends 221 arranged opposite each other along its length, each fixedly connected to the main structure 21. The deformable beam 22 also includes a strain zone 222 located between the two fixed ends 221, with a connection area 223 between the strain zone 222 and the fixed ends 221. The width of the connection area 223 is smaller than the width of both the fixed ends 221 and the strain zone 222. When the deformable beam 22 is subjected to stress, the strain zone 222 can achieve a large deformation. Strain gauges 23 are symmetrically arranged in the strain zone 222 to sense the deformation of the strain zone 222 and generate corresponding deformation. To improve the deformation performance of the strain zone 222, it is preferable that the strain zone 222 has a perforation 2221. The perforation 2221 allows the strain zone 222 to achieve a larger deformation, improving torque detection performance. The shape of the perforation 2221 can be various, but it is preferably a shape that allows the strain zone 222 to be subjected to uniform stress, such as a rectangular hole, an oval hole, or other centrally symmetrical shapes. Figure 3 In the illustrated embodiment, the cutout 2221 is a rectangular hole, and preferably the corners of the rectangular hole are rounded to reduce stress concentration. In other embodiments of this application, the strain gauge 23 may be disposed on the hole wall of the cutout 2221 along the width direction, but considering the difficulty of installation, it is usually not disposed on the hole wall of the cutout 2221.

[0063] To enhance the safety factor, the connection area 223 is further smoothly connected to the fixed end 221 and the strain zone 222. "Smooth connection" includes a rounded connection, i.e., rounded corners are used in the transition area to reduce stress concentration. For a smooth connection, a rounded surface with a large or small radius of curvature can be used for the transition; specific requirements are not specified. A smooth connection ensures uniform stress distribution in the transition area between the connection area 223, the fixed end 221, and the strain zone 222, reducing the risk of fracture.

[0064] A reinforcing region 224 is preferably provided between the strain zone 222 and the connecting region 223. The width of the reinforcing region 224 is greater than the width of both the strain zone 222 and the connecting region 223. The reinforcing region 224 improves the bending strength of the strain zone 222 and reduces its bending deformation, thereby minimizing the impact of bending deformation on torque measurement. Preferably, the reinforcing region 224 is smoothly connected to both the strain zone 222 and the connecting region 223. Figure 3In the illustrated embodiment, a large arc surface is used for the transition between the connecting area 223 and the fixed end 221 and the reinforcing area 224, so that the two opposite sides of the connecting area 223 along the width direction are also basically arc surfaces. Furthermore, the width of the fixed end 221 is equal to the width of the reinforcing area 224.

[0065] The two opposite sides of the strain zone 222 along the width direction (i.e., the sides away from the cutout 2221) are preferably arranged in parallel, and strain gauges 23 are mounted on the two parallel sides of the strain zone 222. Mounting strain gauges 23 on the parallel sides of the strain zone 222 further reduces the influence of bending deformation on torque measurement. However, in other embodiments of this application, the two opposite sides of the strain zone 222 along the width direction may not be arranged in parallel, but they need to be symmetrical about the axis along the length direction. Therefore, under torque, both strain gauges 23 located on the deformable beam 22 are either axially stretched or axially compressed.

[0066] The fixed end 221 is fixedly connected to the main structure 21 by a suitable method, such as using a pin connection or screw connection, or a snap-fit ​​connection combined with adhesive bonding. (Reference) Figure 3 and Figure 5 and Figure 6 In the illustrated embodiment, the fixed end 221 is provided with a lug 2211, and the recess 213 is provided with hooks 215 that mate with the lug 2211 on two opposite sides along the circumferential direction. To ensure the reliability of the fixation, it is preferable to use adhesive to bond the fixed end 221 to the main structure 21 when the connection is made by snapping. Optionally, the recess 213 is provided with mounting holes 214 that mate with the fixed end 221 on two opposite sides along the circumferential direction of the first part 211.

[0067] refer to Figure 2 Optionally, the outer edge of the main structure 21 is also provided with a clearance notch 216, which does not coincide with the notch 213. The clearance notch 216 is used to avoid related structures on the joint of the robotic arm. Multiple clearance notches 216 can be provided, and the multiple clearance notches 216 are evenly arranged along the circumference of the main structure 21.

[0068] <Example 2>

[0069] The following mainly describes the differences from Embodiment 1. For the parts that are the same as in Embodiment 1, please refer to Embodiment 1.

[0070] Please refer to Figure 7In Embodiment 2 of this application, the main structure 21 is an integral or one-piece molded structure. Compared with a split design, the one-piece main structure 21 is more conducive to processing and molding, and can better control the shape and size of the main structure 21, ensuring the accuracy of torque detection. The difference from Embodiment 1 is that the avoidance notch 216 is removed from the main structure 21.

[0071] <Example 3>

[0072] The following mainly describes the differences from Embodiment 1 and Embodiment 2 described above. For the parts that are the same as those in Embodiment 1 and Embodiment 2 described above, please refer to Embodiment 1 and Embodiment 2 described above.

[0073] Please refer to Figure 8 In Embodiment 3 of this application, the main structure 21 is an integral or one-piece molded structure, but the difference from Embodiment 2 is that the one-piece main structure 21 is provided with an avoidance notch 216.

[0074] <Example 4>

[0075] The following mainly describes the differences from Embodiment 1 above. For the parts that are the same as in Embodiment 1, please refer to Embodiment 1 above.

[0076] Please refer to Figure 9 In Embodiment 4 of this application: the reinforcing area 224 of the deformable beam 22 is eliminated; a small rounded corner is used to transition between the connecting area 223 and the fixed end 221 and the reinforcing area 224, so that the two opposite sides of the connecting area 223 along the width direction are basically flat; a square cutout 2221 is used instead of a rectangular cutout 2221; the length of the fixed end 221 along the length direction is increased to increase the connection strength.

[0077] <Example 5>

[0078] The following mainly describes the differences from Embodiment 1 above. For the parts that are the same as in Embodiment 1, please refer to Embodiment 1 above.

[0079] Please refer to Figure 10 In Embodiment 5 of this application: the reinforcing area 224 of the deformable beam 22 is eliminated; a small rounded corner is used to transition between the connecting area 223 and the fixed end 221 and the reinforcing area 224, but the two opposite sides of the connecting area 223 along the width direction are partially curved; a square cutout 2221 is used instead of a rectangular cutout 225; the length of the fixed end 221 along the length direction is increased to increase the connection strength.

[0080] <Example 6>

[0081] The following mainly describes the differences from the above embodiment one. For the parts that are the same as the above embodiment, please refer to the above embodiment one.

[0082] Please refer to Figure 11 In Embodiment Six of this application: a small rounded corner is used to transition between the connecting area 223 and the fixed end 221 and the reinforcing area 224, so that the two opposite sides of the connecting area 223 along the width direction are basically flat; the width of the fixed end 221 is greater than the width of the reinforcing area 224 to increase the connection strength; the four corners of the rectangular cutout 2221 are adjusted and a larger radius is used for rounded corner transition.

[0083] <Example 7>

[0084] The following mainly describes the differences from Embodiment 1 above. For the parts that are the same as in Embodiment 1 above, please refer to Embodiment 1 above.

[0085] Please refer to Figure 12 The connection between the deformable beam 22 and the main structure 21 is a screw connection. Each fixed end 221 can be connected by two screws 24, and the deformable beam 22 can be fixed from the left and right directions. The advantages of screw connection include: (1) it can ensure better connection strength; (2) it reduces the requirements for the machining accuracy of parts and saves costs; (3) it is easy to install and improves production efficiency; (4) it is easy to disassemble and is very beneficial for the replacement and maintenance of parts in the later stage.

[0086] <Example 8>

[0087] The following mainly describes the differences from Embodiment 1 above. For the parts that are the same as in Embodiment 1 above, please refer to Embodiment 1 above.

[0088] Please refer to Figure 13 The deformable beam 22 is connected to the main structure 21 by screws. Each fixed end 221 can be connected by two screws 24 and the deformable beam 22 is fixed from the front and rear directions.

[0089] <Example 9>

[0090] The following mainly describes the differences from Embodiment 1 above. For the parts that are the same as in Embodiment 1 above, please refer to Embodiment 1 above.

[0091] Please refer to Figure 14 The deformable beam 22 is connected to the main structure 21 by a pin connection. Each fixed end 221 can be connected by a pin 25, which fixes the deformable beam 22 from the top and bottom. The advantages of the pin connection are similar to those of the screw connection, and will not be explained further.

[0092] It should be noted that those skilled in the art can make various improvements and additions without departing from the method of this invention, and these improvements and additions should also be considered within the scope of protection of this invention. Any modifications, alterations, and variations made by those skilled in the art without departing from the spirit and scope of this invention, based on the disclosed technical content, are equivalent embodiments of this invention; furthermore, any modifications, alterations, and variations made to the above embodiments based on the essential technology of this invention still fall within the scope of the technical solution of this invention.

Claims

1. A torque detection device, characterized in that: It comprises a main structure and at least one deformable beam; two opposite sides of the main structure along a direction perpendicular to its own axis are used to be fixedly connected to the torque input end and the torque output end respectively; At least one notch is provided at the outer edge of the main structure, and one deformation beam is provided in each of the notches; the length of the deformation beam corresponds to the circumferential arrangement of the main structure, and the two opposite fixed ends of the deformation beam along its own length are respectively fixedly connected to the main structure.

2. The torque detection device according to claim 1, characterized in that: The deformable beam is a centrally symmetrical structure, and has a strain zone located between the two fixed ends. A connecting zone is provided between the strain zone and the fixed ends, and a width of the connecting zone is smaller than a width of the fixed ends and a width of the strain zone.

3. The torque detection device according to claim 2, characterized in that: The strain area is provided with a hollow.

4. The torque detection device according to claim 2, characterized in that: The connection area is smoothly connected to the fixed end and the strain area.

5. The torque detection device according to claim 2, characterized in that: A reinforcement zone is arranged between the connection zone and the strain zone, the width of the reinforcement zone is greater than the width of the strain zone and the width of the connection zone, and the reinforcement zone is smoothly connected to the strain zone and the connection zone.

6. The torque detection device according to claim 2, characterized in that: Two opposite side surfaces of the strain zone along the width direction are arranged in parallel, and the two parallel side surfaces of the strain zone are used for installing strain gauges.

7. The torque detection device according to claim 2, characterized in that: The axial direction of the deformation beam is perpendicular to the radial direction of the main structure, so that the deformation beam is only subjected to the force along its own axial direction.

8. The torque detection device according to claim 2, characterized in that: There are multiple notches, and the multiple notches are evenly arranged along the circumference of the main structure, and one deformation beam is arranged in each notch.

9. The torque detection device according to any one of claims 1 to 8, characterized in that: The fixed end is connected to the main structure by pins or screws, or the fixed end is connected to the main structure by snap-fitting and bonding with glue.

10. The torque detection device according to claim 9, characterized in that: When the fixed end is connected to the main structure by snap-fitting, the fixed end is provided with a lug, and two opposite sides of the recess along the circumference of the main structure are respectively provided with hooks that cooperate with the lug.

11. The torque detection device according to any one of claims 1 to 8, characterized in that: The main structure is a centrally symmetrical structure and has a through central hole.

12. The torque detection device according to claim 11, characterized in that: The main structure is a split structure or an integrated structure.

13. The torque detection device according to claim 11, characterized in that: The outer edge of the main structure is also provided with an avoidance gap, and the avoidance gap does not overlap with the notch.

14. The torque detection device according to any one of claims 1 to 8, characterized in that: Also included are strain gauges, where: At least two of the strain gauges are arranged on the main structure, and at least two of the strain gauges are arranged on one of the deformation beams, and the at least two strain gauges on the main structure and the at least two strain gauges on one of the deformation beams form a Wheatstone bridge; Alternatively, there are multiple deformable beams, at least two strain gauges are arranged on each deformable beam, and at least four strain gauges on any two deformable beams form a Wheatstone bridge; Alternatively, there are multiple deformation beams, at least four strain gauges are arranged on the main structure, at least two strain gauges are arranged on each deformation beam, and the at least two strain gauges on each deformation beam and the corresponding at least two strain gauges on the main structure form a Wheatstone bridge.

15. A mechanical arm joint, characterized in that: It includes a torque input end, a torque output end and a torque detection device as described in any one of claims 1 to 14, wherein the torque input end, the torque detection device and the torque output end are connected in sequence and coaxially arranged, and when viewed from the axial direction of the torque detection device, two opposite sides of the main structure in the torque detection device are fixedly connected to the torque input end and the torque output end respectively.

16. A robotic arm, characterized in that: It is composed of multiple robot arm joints according to claim 15.

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