Torque sensor and power tool

Abstract

The utility model is suitable for sensor technical field provides a kind of torsion sensor and electric tool, torsion sensor includes strain beam, strain detection component, first connecting body and second connecting body, strain beam is used to strain synchronously when the force of to-be-detected object, strain detection component is used to detect the strain of strain beam and produce detection signal. First connecting body is connected with anyone of fixed object or to-be-detected object, and second connecting body is connected with another one of fixed object or to-be-detected object. By setting first engagement structure on first connecting body and second engagement structure on second connecting body, the engagement of fixed object and to-be-detected object can be quickly achieved, and the installation of the whole torsion sensor is realized, which is convenient for connection and disassembly. At the same time, the detection force transmission is sensitive, the interference is low, the detection accuracy of the torsion sensor is improved, and the safety and reliability of the electric tool are improved.

Description

Technical Field

[0001] This utility model belongs to the field of sensor technology, and in particular relates to a torque sensor and a power tool. Background Technology

[0002] With the development of technology, torque sensors have been widely used in the fields of automated machinery, robotics, and medical devices. Currently, torque sensors generally adopt a flange structure with threads or through holes at both ends, and are then installed using screws.

[0003] In this structure, the sensor is fixed using a flange and screws. Tightening the screws during installation can easily cause a change in the sensor's zero point, affecting measurement accuracy. Furthermore, disassembly and assembly are inconvenient in confined spaces. Therefore, it is necessary to address both the ease of disassembly and assembly and the impact on measurement accuracy. Utility Model Content

[0004] In view of this, the present invention provides a torque sensor and a power tool to solve the problems of poor ease of installation and disassembly of torque sensors and the impact on measurement accuracy.

[0005] To solve the above problems, the technical solution of this utility model is implemented as follows:

[0006] A torque sensor is connected between a fixed object and an object to be tested. The torque sensor includes: a strain beam for synchronously generating strain when the object to be tested is subjected to force; a strain detection component at least partially connected to the strain beam for detecting the strain generated by the strain beam and generating a detection signal; a first connector connected to one end of the strain beam for connecting to either the fixed object or the object to be tested; and a second connector connected to the other end of the strain beam for connecting to the other of the fixed object or the object to be tested. The first connector has a first engagement structure, and the second connector has a second engagement structure, which engage with mating structures on the fixed object or the object to be tested.

[0007] In some embodiments, the first meshing structure and the second meshing structure are either a spur gear set or a stepped gear set.

[0008] In some embodiments, the first engagement structure and the second engagement structure are not the same.

[0009] In some embodiments, the strain detection assembly includes: a strain gauge connected to the strain beam for detecting the stress strain of the strain beam; and a circuit board disposed on any one of the strain beam, the first connector, and the second connector, wherein the strain gauge is electrically connected to the circuit board.

[0010] In some embodiments, the cross-sectional shape of the strain beam along the vertical axis is circular.

[0011] In some embodiments, the circumferential array of strain beams is provided with an even number, and the number is not less than four; wherein, at least four symmetrically distributed strain beams are provided with strain gauges.

[0012] In some embodiments, the strain beam has axial holes extending through both ends.

[0013] In some embodiments, the outer peripheral wall of the strain beam is provided with a plurality of through slots that connect shaft holes, and each of the through slots is evenly spaced around the axis of the strain beam.

[0014] In some embodiments, a connection position for connecting the strain gauge is formed between two adjacent through slots, and the strain gauge is disposed on at least four symmetrically distributed connection positions.

[0015] This utility model also provides a power tool, including a body and the torque sensor described in any of the above embodiments, wherein the torque sensor is disposed within the body.

[0016] This utility model provides a torque sensor and power tool. The torque sensor includes a strain beam, a strain detection component, a first connecting body, and a second connecting body. The strain beam synchronously undergoes strain when the object to be tested is subjected to force. The strain detection component detects the strain in the strain beam and generates a detection signal. The first connecting body is connected to either the fixed object or the object to be tested, and the second connecting body is connected to the other of the fixed object or the object to be tested. This utility model employs a first engagement structure on the first connecting body and a second engagement structure on the second connecting body. By engaging the first and second engagement structures with the mating structures on the fixed object or the object to be tested, the entire torque sensor can be connected to both the fixed object and the object to be tested, making connection convenient and disassembly easy. Simultaneously, the force transmission is sensitive and interference is low, thus improving the detection accuracy of the torque sensor and enhancing the safety and reliability of the power tool. Attached Figure Description

[0017] Figure 1 This is a three-dimensional structural diagram of the torque sensor provided in the embodiment of this utility model in the first position;

[0018] Figure 2 This is a three-dimensional structural diagram of the torque sensor provided in the embodiment of this utility model in the second position;

[0019] Figure 3 This is a schematic diagram showing the connection between the torque sensor, the fixed object, and the object to be tested provided in this embodiment of the utility model;

[0020] Figure 4 This is a three-dimensional structural diagram of a torque sensor with another structure provided in an embodiment of this utility model.

[0021] Explanation of reference numerals in the attached figures:

[0022] 1. Torque sensor; 11. Strain beam; 111. Shaft hole; 12. Strain detection assembly; 121. Strain gauge; 13. First connector; 131. First meshing structure; 14. Second connector; 141. Second meshing structure;

[0023] 20. Fitting structure; 21. Fixing object; 22. Object to be tested. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0025] The specific technical features described in the specific embodiments can be combined in any suitable manner without contradiction. For example, different combinations of specific technical features can form different embodiments and technical solutions. To avoid unnecessary repetition, the various possible combinations of the specific technical features in this utility model will not be described separately.

[0026] In the following description, the terms "first," "second," and "..." are used merely to distinguish different objects and do not indicate that the objects have the sameness or relationship. It should be understood that the directional descriptions "above," "below," "outside," and "inside" refer to the orientation under normal use conditions, while "left" and "right" refer to the left and right directions shown in the corresponding diagrams, which may or may not be the left and right directions under normal use conditions.

[0027] It should be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. "A plurality of" means two or more.

[0028] like Figure 1 and Figure 3 As shown in the figure, the present invention provides a torque sensor 1, which is connected between a fixed object 21 and an object to be tested 22. When the object to be tested 22 is subjected to force, the torque sensor 1 can be subjected to force and undergo strain synchronously. Then, under the action of the detection signal generated by the strain of the torque sensor 1, the force condition (such as the magnitude or direction of the force) of the object to be tested 22 can be detected.

[0029] like Figure 1 and Figure 2 As shown, the torque sensor 1 includes a strain beam 11, a strain detection component 12, a first connecting body 13, and a second connecting body 14. The strain beam 11 is used to synchronously generate strain when the object to be tested 22 is subjected to force. The first connecting body 13 and the second connecting body 14 are respectively connected to opposite ends of the strain beam 11. The strain detection component 12 is at least partially connected to the strain beam 11. The strain detection component 12 is used to detect the strain generated in the strain beam 11 and generate a detection signal, thereby enabling the detection of the force on the object to be tested 22 based on the generated detection signal.

[0030] Specifically, the connection between the first connecting body 13 and the second connecting body 14 and the strain beam 11 can be integrally formed, or they can be fixedly connected to the strain beam 11 by welding. In the specific connection, the first connecting body 13 is connected to either the fixed object 21 or the object to be tested 22, and the second connecting body 14 is connected to the other one of the fixed object 21 or the object to be tested 22. That is, the first connecting body 13 can be used to connect to either the fixed object 21 or the object to be tested 22, and the second connecting body 14 can also be used to connect to either the fixed object 21 or the object to be tested 22. The connection is flexible, and it is only necessary to ultimately connect the first connecting body 13 to one of the fixed object 21 or the object to be tested 22, and the second connecting body 14 to the other one of the fixed object 21 or the object to be tested 22.

[0031] The strain gauge detection assembly 12 is used to detect the stress on the strain beam 11. In the detection environment, the force exerted on the object to be tested 22 is transferred to the strain beam 11, causing it to deform under the influence of external force. By detecting the degree of deformation (also known as stress-strain), the change in the current force can be determined. Specifically, the strain gauge assembly 12 contains strain gauges, which are typically made of conductor or semiconductor materials and have a sensitive grid structure, 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, the strain gauges are attached to the strain beam 11 and arranged in a Wheatstone bridge. When the strain beam 11 is subjected to force, strain occurs, causing the strain gauges to strain synchronously. Consequently, the sensitive grid deforms, changing its resistance. This change in resistance generates a measurable voltage difference in the Wheatstone bridge, thus converting the measured force into a measurable voltage signal.

[0032] In the embodiments of this utility model, such as Figures 1 to 3 As shown, a first meshing structure 131 is provided on the first connecting body 13, and a second meshing structure 141 is provided on the second connecting body 14. The first meshing structure 131 and the second meshing structure 141 are respectively meshed and connected to the mating structure 20 provided on the fixed object 21 or the object to be tested 22. Specifically, "meshing connection" means that the connected objects have complementary shapes or structures (such as convex and concave structures, gear teeth, and the conical surface and groove of a pipe pile), which can achieve cross-meshing and form a self-locking effect. After the torque sensor 1 is connected to the corresponding object by the meshing connection, it can achieve synchronous movement and force transmission without the need for connection and fixation by screw-like fasteners. The connection is convenient, and it can better avoid the situation where the zero point of the sensor changes due to the stress generated by tightening the screws when the connection is fixed by screws, thus avoiding the situation where the detection result is inaccurate. By setting it to meshing connection, not only can the detection accuracy be improved, but the mutually cooperating connection structure is simple, and there is no need to set up related structures for fixing screws, thereby saving installation space. Under the same structure, the range of the torque sensor 1 can be increased by increasing the size of the strain beam 11, thus expanding the range of applications of the torque sensor 1.

[0033] Specifically, both the fixture 21 and the object to be tested 22 are provided with mating structures 20, which are used to mate with the corresponding structures to achieve connection. For example, if the mating structure 20 on the fixture 21 is used to connect with the first meshing structure 131 on the first connecting body 13, then the mating structure 20 on the fixture 21 is configured to be compatible with the first meshing structure 131, ensuring easy meshing between the first meshing structure 131 and the corresponding mating structure 20. Similarly, if the mating structure 20 on the object to be tested 22 is used to connect with the second meshing structure 141 on the second connecting body 14, then the mating structure 20 on the object to be tested 22 is configured to be compatible with the second meshing structure 141, ensuring easy meshing between the second meshing structure 141 and the corresponding mating structure 20. The first meshing structure 131 and the second meshing structure 141 can be the same structure or different structures. When the first meshing structure 131 and the second meshing structure 141 are the same, the mating structures 20 on the fixture 21 and the object to be tested 22 are also the same. When the first meshing structure 131 and the second meshing structure 141 are not the same, the mating structures 20 on the fixture 21 and the object to be tested 22 are also respectively set according to the structures to be connected, to ensure that meshing and connection can be achieved.

[0034] This utility model provides a torque sensor 1, including a strain beam 11, a strain detection component 12, a first connecting body 13, and a second connecting body 14. The strain beam 11 is used to synchronously generate strain when the object to be tested 22 is subjected to force. The strain detection component 12 is used to detect the strain generated by the strain beam 11 and generate a detection signal. The first connecting body 13 is connected to either the fixed object 21 or the object to be tested 22, and the second connecting body 14 is connected to the other of the fixed object 21 or the object to be tested 22. This utility model embodiment uses a first engagement structure 131 on the first connecting body 13 and a second engagement structure 141 on the second connecting body 14. In this way, by engaging the first engagement structure 131 and the second engagement structure 141 with the mating structure 20 provided on the fixed object 21 or the object to be tested 22 respectively, the entire torque sensor 1 can be connected to the fixed object 21 and the object to be tested 22 without the need for operations such as tightening screws, making connection convenient and disassembly easy. Furthermore, since no screw tightening is required, the torque sensor 1, after installation, remains in a stress-free state when connected between the fixed object 21 and the object to be tested 22. This effectively prevents zero-point changes in the torque sensor 1, thus ensuring its detection accuracy. Simultaneously, the sensitive force transmission and low interference further enhance the detection accuracy of the torque sensor 1, improving the safety and reliability of power tool use.

[0035] In some embodiments, such as Figure 1 and Figure 2 As shown, the first meshing structure 131 and the second meshing structure 141 are either a spur gear set or a stepped gear set. By setting them as gear sets, meshing is achieved; during installation, only mutual meshing is required, making installation convenient and reliable. Furthermore, gear meshing transmission ensures transmission sensitivity, allowing the force on the object under test to be transmitted to the strain beam 11 in a timely manner, thus guaranteeing the accuracy of the test.

[0036] Specifically, by setting the first meshing structure 131 and the second meshing structure 141 as either a spur gear set or a stepped gear set, the mating structures 20 on the fixed object 21 and the object to be tested 22 are also adapted accordingly. For example, if both the first meshing structure 131 and the second meshing structure 141 are spur gear sets, then the mating structures 20 on the fixed object 21 and the object to be tested 22 are also set as the same spur gears. Alternatively, when the first meshing structure 131 is set as a spur gear set and connected to the fixed object 21, then the mating structure 20 on the fixed object 21 is set as a spur gear set. When the second meshing structure 141 is set as a stepped gear set and connected to the object to be tested 22, then the mating structure 20 on the object to be tested 22 is set as a stepped gear set. In this way, the mating structures 20 are adapted to the corresponding meshing structures, thereby ensuring ease of assembly and disassembly. Furthermore, when a stepped gear set is used, the stepped design allows for embedding with the corresponding mating structure 20, resulting in a larger contact area and improved connection reliability.

[0037] Understandably, the first meshing structure 131 and the second meshing structure 141 can be set to either a helical gear set or a bevel gear set, as long as meshing transmission can be achieved.

[0038] In some embodiments, the first engagement structure 131 and the second engagement structure 141 are configured to be different. This allows for positional guidance during installation, facilitating accurate installation. Furthermore, the structural differences between the engagement structures facilitate installation and improve installation efficiency.

[0039] In some embodiments, such as Figure 1As shown, the strain detection assembly 12 includes a strain gauge 121 and a circuit board (not shown). The strain gauge 121 is connected to the strain beam 11, and the circuit board is mounted on any one of the strain beam 11, the first connecting body 13, and the second connecting body 14 to fix its installation position. The strain gauge 121 is used to detect the stress and strain of the strain beam 11, so that after the strain beam 11 is subjected to stress and strain, the strain gauge 121 deforms synchronously to generate a detection signal. By electrically connecting the strain gauge 121 to the circuit board, the detection signal generated by the strain gauge 121 can be processed by the circuit board and output to an external detection device, thereby realizing the detection of the stress condition of the strain beam 11.

[0040] Specifically, during actual testing, multiple strain gauges 121 are connected at different positions on the strain beam 11, and these strain gauges 121 are connected together in a specific manner to form a Wheatstone bridge. When the resistance value of the strain gauge 121 changes, the balance of the bridge circuit is broken, thereby generating an output signal proportional to the mechanical quantity. After amplification, filtering, and digitization by the signal processing circuit, this signal can be read and analyzed by terminal devices such as computers, thus obtaining the corresponding stress condition. In this embodiment of the invention, four strain gauges 121 are provided, and the four strain gauges 121 are evenly distributed around the strain beam 11, forming a Wheatstone bridge, thereby realizing the detection of the stress condition of the strain beam 11.

[0041] In some embodiments, the cross-sectional shape of the strain beam 11 along the vertical axis is circular. That is, the strain beam 11 is set as a solid cylindrical structure, thereby having greater structural strength, improving the detection range, and expanding the application range of the torque sensor 1. In this configuration, only one strain beam 11 is provided, and both the first connecting body 13 and the second connecting body 14 are set as annular structures. After the first connecting body 13 and the second connecting body 14 are respectively connected to the opposite ends of the strain beam 11, the centers of the first connecting body 13 and the second connecting body 14 are both located on the axis of the strain beam 11, so that the overall shape is a structure that is basically symmetrical along the axis, which better ensures the force balance during use.

[0042] In some embodiments, an even number of strain beams 11 are arranged in a circumferential array, with a minimum of four; strain gauges 121 are mounted on at least four symmetrically distributed strain beams 11. Specifically, in this arrangement, multiple strain beams 11 are arranged in a circumferential array according to design requirements, with a minimum of four and an even number in total. This allows for a smaller diameter for each strain beam 11, and by enclosing the strain beams 11 into a hollow circle, an overall structure is formed with a detection range that meets the usage requirements. Furthermore, different measurement ranges can be achieved by adjusting the number of strain beams 11. This improves the flexibility of the torque sensor 1's configuration.

[0043] When using at least four (and an even number) strain beams 11, strain gauges 121 can be installed on each strain beam 11, and one or more strain gauges 121 can be connected to each strain beam 11. Depending on the detection requirements, the strain gauges 121 at appropriate positions on the strain beams 11 and the number connected can be combined to form a Wheatstone bridge. Furthermore, depending on the number of strain gauges 121 connected, a full-bridge circuit or a half-bridge circuit can be formed, thereby constructing torque sensors 1 with different detection sensitivities to meet the needs of different situations and expanding the range of applications.

[0044] In some embodiments, such as Figure 1 As shown, the strain beam 11 has shaft holes 111 extending through both ends along its axial direction. By providing shaft holes 111, the strain beam 11 becomes a hollow structure. The parts on the object to be tested 22 used to generate the force to be tested can pass through these shaft holes 111. After the first and second connecting parts are connected to the corresponding fixed object 21 or the object to be tested 22, during the operation of the object to be tested 22, the force is transmitted to the strain beam 11 under the reaction force, causing the strain beam 11 to strain and thus enabling the detection of the output force. For example, to detect the torque generated by the output shaft of a power tool, the output shaft can be inserted into the shaft hole 111. When the output shaft rotates and generates torque, the torque can be transmitted to the strain beam 11, causing the strain beam 11 to strain. This strain is detected by the strain gauge 121, which outputs a detection signal, thereby realizing the detection of the torque magnitude.

[0045] In some embodiments, such as Figure 4 As shown, the strain beam 11 is provided with a shaft hole 111 (see reference). Figure 1Alternatively, multiple through slots 112 with interconnected shaft holes 111 can be formed on the outer peripheral wall of the strain beam 11, with each through slot 112 evenly spaced around the axis of the strain beam 11. In this way, the through slots 112 can reduce the overall structural strength of the strain beam 11, making it easier for strain to occur under stress, thereby improving the sensitivity of detection.

[0046] In some embodiments, when the strain beam 11 is configured with a structure having multiple spaced slots 112, connection positions for supplying strain gauges 121 are formed between adjacent slots 112. Thus, strain gauges 121 are provided at at least four symmetrically distributed connection positions. Under the action of these four strain gauges 121, a Wheatstone full-bridge circuit can be formed, thereby detecting the corresponding torque when strain occurs in the strain beam 11. Furthermore, using at least four symmetrically distributed strain gauges 121 to form a Wheatstone full-bridge circuit also ensures better detection sensitivity.

[0047] This embodiment of the invention also provides a power tool, including a body and a torque sensor 1 as described in any of the above embodiments, with the torque sensor 1 housed within the body. Different components inside the body respectively constitute the fixing element 21 and the object to be detected 22, which will not be elaborated upon here. The power tool is used to output torque, thereby enabling operations such as assembling and disassembling screw-like fasteners. When the power tool outputs torque, the torque sensor 1 can monitor the torque generated during tightening in real time, ensuring that the tightening torque meets the preset standard, avoiding connection failure or material damage due to overtightening or loosening, thus significantly improving the reliability of the power tool.

[0048] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A torque sensor, connected between a fixed object and an object to be detected, characterized in that, The torque sensor includes: A strain beam is used to synchronously generate strain when the object under test is subjected to force. A strain detection assembly is at least partially connected to the strain beam, the strain detection assembly being used to detect the strain occurring in the strain beam and generate a detection signal; A first connector is attached to one end of the strain beam, and the first connector is used to connect to either the fixed object or the object to be tested. A second connector is attached to the other end of the strain beam. The second connector is used to connect to another of the fixed object or the object to be tested. The first connecting body is provided with a first meshing structure, and the second connecting body is provided with a second meshing structure. The first meshing structure and the second meshing structure are respectively meshed and connected with the mating structure provided on the fixed object or the object to be tested.

2. The torque sensor as described in claim 1, characterized in that, The first meshing structure and the second meshing structure are either a spur gear set or a stepped gear set.

3. The torque sensor as described in claim 1, characterized in that, The first meshing structure and the second meshing structure are different.

4. The torque sensor as described in claim 1, characterized in that, The strain detection component includes: A strain gauge is connected to the strain beam and is used to detect the strain of the strain beam under stress. A circuit board is disposed on any one of the strain beam, the first connecting body, and the second connecting body, and the strain gauge is electrically connected to the circuit board.

5. The torque sensor as described in claim 1, characterized in that, The cross-sectional shape of the strain beam along the vertical axis is circular.

6. The torque sensor as described in claim 4, characterized in that, The strain beams are arranged in an even number of circular arrays, with a minimum of four; strain gauges are arranged on at least four symmetrically distributed strain beams.

7. The torque sensor as described in claim 4, characterized in that, The strain beam has through holes at both ends along its axial direction.

8. The torque sensor as described in claim 7, characterized in that, The outer peripheral wall of the strain beam has multiple through slots that connect to shaft holes, and each through slot is evenly spaced around the axis of the strain beam.

9. The torque sensor as described in claim 8, characterized in that, A connection position for connecting the strain gauge is formed between two adjacent through slots, and the strain gauge is disposed on at least four symmetrically distributed connection positions.

10. A power tool, characterized in that, It includes a body and a torque sensor as described in any one of claims 1 to 9, wherein the torque sensor is disposed within the body.

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