A force sensor

Abstract

The embodiment of the present application provides a force sensor, which comprises an inner flange, an outer flange and a plurality of strain beams. The outer flange has a containing space, the inner flange is arranged in the containing space and is arranged in a spaced manner with the outer flange. The strain beams are arranged at intervals between the inner flange and the outer flange, and opposite ends of the strain beams are connected with the inner flange and the outer flange respectively; between at least two adjacent strain beams, a part of the inner wall of the side of the outer flange close to the containing space is protruded to form a protruding part, and the protruding part has at least a part of a connecting hole. The force sensor of the embodiment of the present application has a small size.

Description

Technical Field

[0001] This application relates to the field of sensor technology, and in particular to a force sensor. Background Technology

[0002] Force sensors can measure force or torque and can be widely used in various fields such as humanoid robots, precision assembly, aerospace, and medical equipment. For example, in the field of humanoid robots, force sensors can provide more accurate force information, improving the robot's motion accuracy and reaction speed.

[0003] However, the force sensors in related technologies are large in size and tall, making them unsuitable for mechanisms and equipment with limited space. Utility Model Content

[0004] In view of this, the main objective of the embodiments of this application is to provide a force sensor with a small external size.

[0005] To achieve the above objectives, the technical solution of this application embodiment is implemented as follows: This application provides a force sensor, including: Inner flange; An outer flange having a receiving space, and an inner flange disposed within the receiving space and spaced apart from the outer flange; Multiple strain beams are disposed at the interval between the inner flange and the outer flange, and the opposite ends of the strain beams are respectively connected to the inner flange and the outer flange; between at least two adjacent strain beams, a portion of the inner wall of the outer flange on the side near the receiving space protrudes to form a protrusion, the protrusion having at least a portion of a connecting hole.

[0006] In one embodiment, the plurality of strain beams includes two first strain beams and two second strain beams, the first strain beams and the second strain beams being respectively disposed on opposite sides of the inner flange along a first direction and both extending along the first direction; the two first strain beams are spaced apart along a second direction, and the two second strain beams are spaced apart along the second direction; the first direction is perpendicular to the second direction.

[0007] In one embodiment, the first strain beam has a first connecting end connected to the outer flange, and the second strain beam has a second connecting end connected to the outer flange. On the side of the outer flange near the receiving space, the inner wall of the outer flange has a main body portion located on opposite sides of the protrusion. At least one of the first connecting end and the second connecting end is connected at the junction of the protrusion and the main body portion.

[0008] In one embodiment, the first strain beam has a first patch area on each of its opposite sides along a third direction, and a portion of the first patch area on the side of the two first strain beams that is close to each other is recessed between the first patch areas of the two first strain beams; the third direction is perpendicular to the first direction and the second direction, respectively.

[0009] In one embodiment, the second strain beam has a second patch area on each of its opposite sides along a third direction, and a portion of the side of the two second strain beams that is close to each other is recessed between the second patch areas of the two second strain beams; the third direction is perpendicular to the first direction and the second direction, respectively.

[0010] In one embodiment, between any two adjacent strain beams, the inner wall of the outer flange on the side closest to the receiving space is formed with the protrusion.

[0011] In one embodiment, strain beams are respectively provided in the accommodating space between any two adjacent protrusions.

[0012] In one embodiment, the outer flange includes a plurality of protrusions, the plurality of protrusions including a first protrusion located between two first strain beams and a second protrusion located between two second strain beams, and the center of the inner flange is located on the line connecting the first protrusion and the second protrusion.

[0013] In one embodiment, the connecting hole is a countersunk hole.

[0014] In one embodiment, the outer flange includes a plurality of protrusions along the circumference of the inner flange, the protrusions and the strain beam are spaced apart and alternately arranged, and the center of the inner flange is located in the extension direction of the strain beam.

[0015] This application provides a force sensor comprising an inner flange, an outer flange, and multiple strain beams. The outer flange has a receiving space, and the inner flange is disposed within the receiving space and spaced apart from the outer flange. The strain beams are disposed at the interval between the inner and outer flanges, with their opposite ends connected to the inner and outer flanges, respectively. Thus, by employing an inner and outer flange structure, the force sensor can be easily connected to external structures. Furthermore, since the inner and outer flanges are not arranged along the height direction, the force sensor does not occupy excessive space in the height direction, significantly reducing its height. Additionally, between at least two adjacent strain beams, a portion of the inner wall of the outer flange near the receiving space protrudes to form a protrusion, which has at least a portion of a connecting hole. That is, the protrusion occupies the space between the outer and inner flanges, not the outer space of the outer flange, preventing an increase in the outer circumferential surface of the outer flange due to the protrusion, thereby further reducing the overall size of the force sensor. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of a force sensor according to an embodiment of this application; Figure 2 for Figure 1 Front view of the force sensor; Figure 3 for Figure 2 Rear view of the force sensor; Figure 4 for Figure 1 Wheatstone bridge diagram of a medium force sensor.

[0017] Explanation of reference numerals in the attached figures 10. Inner flange; 20. Outer flange; 20a. Accommodation space; 21. Protrusion; 21a. Connection hole; 211. First protrusion; 212. Second protrusion; 22. Main body; 30. Strain beam; 31. First strain beam; 31a. First patch area; 32. Second strain beam; 32a. Second patch area. Detailed Implementation

[0018] In this application, the orientation or positional relationship of "first direction" and "second direction" is based on the appendix. Figure 2 The orientation or positional relationship shown, the "third-direction" orientation or positional relationship is based on the attached... Figure 1 The orientation or positional relationship shown is for illustrative purposes only and is not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this application.

[0019] In the description of the embodiments of this application, technical terms such as "first," "second," and "third" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0020] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0021] In related technologies, the application scenarios of force sensors are limited by size requirements; force sensors with excessively large dimensions are difficult to apply in mechanisms and equipment with limited space. For example, in force sensors of related technologies, an upper and lower base are spaced apart along the height direction, and a strain beam assembly is set between the upper and lower bases, which is connected to an external structure through the upper and lower bases respectively. However, the aforementioned force sensors are too large in size, making them unsuitable for application in confined spaces.

[0022] The force sensor in this application, by adopting a structure with inner and outer flanges 20, greatly reduces the force sensor's position along the height direction (i.e., Figure 1 The external dimensions of the force sensor (in the third direction) are also reduced. Furthermore, the protrusion 21 formed by the inner bulge of the outer flange 20 for connection with external structures further reduces the overall size of the force sensor, making it suitable for applications with limited size requirements, such as humanoid robots, precision assembly, aerospace, and medical equipment. For example, in the field of industrial robots, force sensors can provide more accurate force information to humanoid robots, improving their motion accuracy and reaction speed. In material handling, assembly, and welding processes, force sensors can be used to monitor and control robot movements in real time, improving operational accuracy and safety. In the medical field, force sensors can be used in rehabilitation robots and surgical robots to improve operational precision.

[0023] One embodiment of this application provides a force sensor; please refer to [link / reference]. Figure 1 The force sensor includes an inner flange 10, an outer flange 20, and multiple strain beams 30.

[0024] The outer flange 20 has a receiving space 20a, and the inner flange 10 is disposed in the receiving space 20a and spaced apart from the outer flange 20.

[0025] The strain beam 30 is disposed at the interval between the inner flange 10 and the outer flange 20, and the opposite ends of the strain beam 30 are respectively connected to the inner flange 10 and the outer flange 20; between at least two adjacent strain beams 30, a portion of the inner wall of the outer flange 20 near the receiving space 20a protrudes to form a protrusion 21, the protrusion 21 having at least a portion of the connecting hole 21a.

[0026] Specifically, the type of force sensor is not limited. It can be a lateral single-dimensional force sensor or a multi-dimensional force sensor. A multi-dimensional force sensor refers to a force sensor capable of simultaneously measuring force and torque components in two or more directions. In a Cartesian coordinate system, force and torque can each be decomposed into three components. Therefore, the most complete form of multi-dimensional force is a six-dimensional force / torque sensor, which can simultaneously measure three force components (Fx, Fy, Fz) and three torque components (Mx, My, Mz). In other words, depending on the specific application, a force sensor can be a single-dimensional force sensor for measuring force / torque in a single direction, a six-dimensional force / torque sensor, or other types of multi-dimensional force / torque sensors.

[0027] The outer flange 20 can be used to connect to an external structure, with its central region forming a receiving space 20a. The inner flange 10 is disposed in the receiving space 20a and is spaced apart from the inner wall of the outer flange 20.

[0028] It should be noted that the specific shape of the inner flange 10 is not limited. For example, the inner flange 10 can be a cylindrical structure.

[0029] It should be noted that the inner flange 10 may also be provided with holes for connection to external structures. For example, the inner flange 10 may have pin holes and threaded holes, and the number of these holes may be one or more.

[0030] Multiple strain beams 30 are provided in the space between the inner flange 10 and the outer flange 20. The strain beams 30 can be used to supply strain gauges. Therefore, when the inner and outer flanges 20 are subjected to external forces, the strain beams 30 will generate strain, and the strain gauges can detect the generation of the strain and convert it into strain value.

[0031] Strain gauges are typically made of metallic conductors or semiconductor materials and have a sensitive grid structure. Types of strain gauges include resistance strain gauges and semiconductor strain gauges; they are elements used to measure strain. When a strain gauge undergoes mechanical deformation under external force, its resistance changes accordingly; this phenomenon is called the "strain effect." In use, strain gauges are attached to the mounting area of ​​the strain beam 30. When the component is subjected to force, strain occurs in the mounting area, and the sensitive grid deforms accordingly, causing a change in its resistance. Multiple strain gauges mounted on the strain beam 30 form a Wheatstone bridge. When the force sensor is subjected to force, the force is transmitted to the strain beam 30, causing it to deform. The resistance of the strain gauges on the strain beam changes, and the corresponding Wheatstone bridge generates a voltage signal, thus completing the force measurement.

[0032] In fact, the outer flange 20 is arranged circumferentially around the inner flange 10 and is located outside the inner flange 10, while the strain beam 30 is located between the inner and outer flanges 20. Thus, the inner flange 10, the outer flange 20 and the strain beam 30 can be arranged in the same plane direction, which can reduce the size of the force sensor along the height direction.

[0033] On the side of the outer flange 20 near the receiving space 20a, a portion of the inner wall of the outer flange 20 protrudes, thus forming a protrusion 21. The connection hole 21a on the protrusion 21 is a hole structure for connecting with an external structure.

[0034] It should be noted that the specific type of the connection hole 21a is not limited.

[0035] For example, the connecting hole 21a is a countersunk hole, which can accommodate the end of the connector, effectively eliminating surface protrusions and avoiding interference.

[0036] The inner wall of the outer flange 20 has a protrusion 21 formed by a protrusion, the purpose of which is to provide a connection hole 21a. It should be noted that the connection hole 21a may be entirely located on the protrusion 21, or it may be partially located on the protrusion 21 while the other part is located in other areas of the outer flange 20.

[0037] It should be noted that the number of protrusions 21 is not limited. The outer flange 20 may have only one protrusion 21 or multiple protrusions 21, such as 2, 4, 6 or 8. Furthermore, the specific arrangement between the protrusions 21 and the strain beam 30 is not limited.

[0038] For example, please see Figure 1Between any two adjacent strain beams 30, a protrusion 21 is formed on the inner wall of the outer flange 20 near the receiving space 20a. That is, along the circumference of the outer flange 20, at least one protrusion 21 is formed between any two adjacent strain beams 30. This facilitates the connection between the outer flange 20 and the external structure, improving the stability of the connection.

[0039] For example, please refer to Figure 1 Each strain beam 30 is provided within the accommodating space 20a between any two adjacent protrusions 21. For multiple protrusions 21, at least one strain beam 30 is provided between any two adjacent protrusions 21. This improves the measurement effect of the force sensor and facilitates the placement of strain gauges in the force sensor.

[0040] In the force sensor of this embodiment, the structural design of inner and outer flanges 20 facilitates connection between the force sensor and external structures. Furthermore, since the inner flange 10 and outer flange 20 are not arranged along the height direction, the force sensor does not occupy excessive space in the height direction, significantly reducing its height. Additionally, between at least two adjacent strain beams 30, a portion of the inner wall of the outer flange 20 near the receiving space 20a protrudes to form a protrusion 21, which has at least a portion of the connecting hole 21a. In other words, the protrusion 21 occupies the space between the outer flange 20 and the inner flange 10, rather than the outer space of the outer flange 20, preventing an increase in the outer circumferential surface of the outer flange 20 due to the protrusion 21, thus further reducing the overall size of the force sensor.

[0041] In one embodiment, please refer to Figures 1 to 3 The plurality of strain beams 30 includes two first strain beams 31 and two second strain beams 32. The first strain beams 31 and the second strain beams 32 are respectively disposed on opposite sides of the inner flange 10 along a first direction, and both extend along the first direction. The two first strain beams 31 are spaced apart along a second direction, and the two second strain beams 32 are spaced apart along the second direction. The first direction is perpendicular to the second direction. This significantly reduces crosstalk errors, thereby improving the measurement accuracy of the force sensor for external forces / torques along the first direction.

[0042] Specifically, the first strain beam 31 and the second strain beam 32 are both arranged along the first direction, and the first strain beam 31 and the second strain beam 32 are in one-to-one correspondence and located in the same extension direction.

[0043] The two first strain beams 31 are spaced apart and arranged in parallel along the second direction. Similarly, the two second strain beams 32 are also spaced apart and arranged in parallel along the second direction.

[0044] Therefore, please refer to Figure 4 When an external load acts on the force sensor along the first direction, a Wheatstone bridge can be formed by the strain gauges attached to the first strain beam 31 and the second strain beam 32, which can accurately measure the force on the force sensor.

[0045] It should be noted that the specific mounting method of the strain gauges on the first strain beam 31 and the second strain beam 32 can be set according to the actual situation.

[0046] For example, strain gauges are attached to both sides of each first strain beam 31 and each second strain beam 32 along a third direction. This allows for better coordination between the strain beams 30 to measure external forces, where the third direction is perpendicular to both the first and second directions.

[0047] In one specific embodiment, the force sensor further includes an upper cover plate and a lower cover plate, which are respectively disposed on opposite sides of the outer flange 20 along a third direction. The upper and lower cover plate structure effectively seals the accommodating space 20a, while the force sensor has a relatively small height, meeting the IP65 requirement.

[0048] In one embodiment, please refer to Figures 1 to 3 The first strain beam 31 has a first connecting end that connects to the outer flange 20, and the second strain beam 32 has a second connecting end that connects to the outer flange 20. On the side of the outer flange 20 near the receiving space 20a, the inner wall of the outer flange 20 has a main body portion 22 located on opposite sides of the protrusion 21. At least one of the first connecting end and the second connecting end is connected at the junction of the protrusion 21 and the main body portion 22. This allows for better force transmission and force reception within the force sensor.

[0049] Specifically, the main body 22 refers to the area on the inner wall of the outer flange 20 that does not protrude toward the receiving space 20a.

[0050] Depending on the actual situation, a protrusion 21 may be formed between the two first strain beams 31, with one end of each of the two first strain beams 31 connected to the junction of the protrusion 21 and the main body 22 on opposite sides. Alternatively, a protrusion 21 may be formed between the two second strain beams 32, with one end of each of the two second strain beams 32 connected to the junction of the protrusion 21 and the main body 22 on opposite sides. Alternatively, protrusions 21 may be formed between both the two first strain beams 31 and the two second strain beams 32, with each first strain beam 31 and each second strain beam 32 connected to the junction of the corresponding protrusion 21 and the main body 22.

[0051] It should be noted that by connecting the end of the strain beam 30 to the junction of the protrusion 21 and the main body 22, the connection between the strain beam 30 and the outer flange 20 can be made more stable, resulting in better force transmission and stress distribution between the inner flange 10, the strain beam 30 and the outer flange 20.

[0052] In one embodiment, please refer to Figure 2 and Figure 3 The first strain beam 31 has a first patch area 31a on each of its opposite sides along a third direction. Between the first patch areas 31a of the two first strain beams 31, a portion of the side of the two first strain beams 31 that is close to each other is recessed. The third direction is perpendicular to the first direction and the second direction, respectively. As a result, the first strain beam 31 can better generate strain after being subjected to force, so as to facilitate the detection by strain gauges.

[0053] Specifically, the first patch area 31a is the area on the first strain beam 31 used for supplying the strain gauge. Between the two first patch areas 31a, by recessing the area of ​​the first strain beam 31 located there, the cross-sectional size of the first strain beam 31 at this location can be reduced, thereby facilitating deformation of the first strain beam 31.

[0054] It should be noted that the specific shape of the aforementioned recess is not limited. For example, the first strain beam 31 forms an arc-shaped groove through the recess.

[0055] In one embodiment, please refer to Figure 2 and Figure 3 The second strain beam 32 has second patch areas 32a on opposite sides along a third direction. Between the second patch areas 32a of the two second strain beams 32, a portion of the side of the two second strain beams 32 that is close to each other is recessed. The third direction is perpendicular to the first direction and the second direction, respectively. Therefore, it is easier for the second strain beam 32 to generate strain after being subjected to force, so that the strain gauge can detect it.

[0056] Specifically, the second patch area 32a is the area on the second strain beam 32 used for supplying the strain gauge. Between the two second patch areas 32a, by recessing the area of ​​the second strain beam 32 located there, the cross-sectional size of the second strain beam 32 at this location can be reduced, thereby facilitating deformation of the second strain beam 32.

[0057] It should be noted that the specific shape of the aforementioned recess is not limited. For example, the second strain beam 32 forms an arc-shaped groove through the recess.

[0058] In one embodiment, please refer to Figures 1 to 3The outer flange 20 includes multiple protrusions 21, including a first protrusion 211 located between two first strain beams 31 and a second protrusion 212 located between two second strain beams 32. The center of the inner flange 10 is located on the line connecting the first protrusion 211 and the second protrusion 212. This improves the force sensor's force reception and transmission performance.

[0059] Specifically, the first protrusion 211 is a protrusion 21 located between the two first strain beams 31, and the second protrusion 212 is a protrusion 21 located between the two second strain beams 32. Since the line connecting the first protrusion 211 and the second protrusion 212 passes through the center of the inner flange 10, this makes the overall structure of the force sensor more symmetrical. When the inner flange 10 or the outer flange 20 is subjected to force, it can be transmitted more evenly to each strain beam 30, thus improving the force transmission and measurement effect of the force sensor.

[0060] In some embodiments, the outer flange 20 includes a plurality of protrusions 21 along the circumference of the inner flange 10, the protrusions 21 and the strain beam 30 being spaced apart and alternately arranged, and the center of the inner flange 10 being located in the extending direction of the strain beam 30. This facilitates the measurement of multidimensional forces / torques by force sensors.

[0061] For example, the force sensor includes four strain beams 30, which are circumferentially spaced around the inner flange 10, with adjacent strain beams 30 extending perpendicularly. This allows the strain beams 30 to form a cross shape, facilitating the measurement of multidimensional forces / torques.

[0062] In the description of this application, the references to terms such as "in one embodiment," "in some embodiments," "in a specific embodiment," or "exemplary," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the embodiments of this application. In this application, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Furthermore, without contradiction, those skilled in the art can combine the different embodiments or examples described in this application, as well as the features of the different embodiments or examples.

[0063] The above are merely preferred embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application are included within the protection scope of this application.

Claims

1. A force sensor, characterized in that, include: Inner flange; An outer flange having a receiving space, and an inner flange disposed within the receiving space and spaced apart from the outer flange; Multiple strain beams are disposed at the interval between the inner flange and the outer flange, and the opposite ends of the strain beams are respectively connected to the inner flange and the outer flange; between at least two adjacent strain beams, a portion of the inner wall of the outer flange on the side near the receiving space protrudes to form a protrusion, the protrusion having at least a portion of a connecting hole.

2. The force sensor according to claim 1, characterized in that, The plurality of strain beams includes two first strain beams and two second strain beams, the first strain beams and the second strain beams being respectively disposed on opposite sides of the inner flange along a first direction and both extending along the first direction; the two first strain beams are spaced apart along a second direction, and the two second strain beams are spaced apart along the second direction; the first direction is perpendicular to the second direction.

3. The force sensor according to claim 2, characterized in that, The first strain beam has a first connecting end that connects to the outer flange, and the second strain beam has a second connecting end that connects to the outer flange. On the side of the outer flange near the receiving space, the inner wall of the outer flange has a main body portion located on opposite sides of the protrusion. At least one of the first connecting end and the second connecting end is connected at the junction of the protrusion and the main body portion.

4. The force sensor according to claim 2 or 3, characterized in that, The first strain beam has a first patch area on each of its opposite sides along a third direction. Between the first patch areas of the two first strain beams, a portion of the area on the side of the two first strain beams that are close to each other is recessed. The third direction is perpendicular to the first direction and the second direction, respectively.

5. The force sensor according to claim 2 or 3, characterized in that, The second strain beam has a second patch area on each of its opposite sides along a third direction. Between the second patch areas of the two second strain beams, a portion of the area on the side of the two second strain beams that is close to each other is recessed. The third direction is perpendicular to the first direction and the second direction, respectively.

6. The force sensor according to any one of claims 1-3, characterized in that, Between any two adjacent strain beams, the inner wall of the outer flange on the side near the receiving space is formed with the protrusion.

7. The force sensor according to any one of claims 1-3, characterized in that, Each of the strain beams is provided in the accommodating space between any two adjacent protrusions.

8. The force sensor according to claim 2 or 3, characterized in that, The outer flange includes a plurality of protrusions, including a first protrusion located between two first strain beams and a second protrusion located between two second strain beams, and the center of the inner flange is located on the line connecting the first protrusion and the second protrusion.

9. The force sensor according to any one of claims 1-3, characterized in that, The connecting hole is a countersunk hole.

10. The force sensor according to claim 1, characterized in that, The outer flange includes a plurality of protrusions along the circumference of the inner flange. The protrusions and the strain beam are spaced apart and alternately arranged. The center of the inner flange is located in the extension direction of the strain beam.

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