Handheld electric tool and control method of handheld electric tool

Abstract

The embodiment of the invention relates to the technical field of electric tools, and provides a handheld electric tool and a control method of the handheld electric tool. In the handheld electric tool, a sliding sleeve shell, a load detection assembly and a control unit act synergistically, and the displacement of the sliding sleeve shell directly reflects the load characteristic of a machined object; the load detection assembly detects the displacement of the sliding sleeve shell in the preset direction in real time, generates a target electric signal corresponding to the load, and achieves the precise quantitative sensing of the load. The control unit generates a duty ratio control instruction based on the target electric signal so as to adjust the output power of the driving device, the output of the handheld electric tool is actively adjusted according to the load of the machined object, the problems that a traditional handheld electric tool depends on manual force application, safety is low, and machining quality is unstable are solved, and the machining efficiency is improved. Efficient, safe and intelligent machining operation is achieved, and meanwhile the service life of equipment can be effectively prolonged.

Description

Technical Field

[0001] Embodiments of the present disclosure relate to the technical field of power tools, and particularly to a handheld power tool and a control method thereof. Background Art

[0002] Currently, the control systems and overall designs of handheld power tools such as angle grinders and cutters mainly rely on the user manually applying external force to drive the tool for cutting or grinding operations. Especially when dealing with high-density materials, the user needs to exert effort to push the tool, resulting in low operation efficiency, high safety risks, and unstable processing quality. Therefore, there is an urgent need for a handheld power tool that can intelligently adjust the output to solve the above defects. Summary of the Invention

[0003] Embodiments of the present disclosure provide a handheld power tool and a control method thereof, which are at least beneficial to solving the problems of laborious operation and low efficiency of existing handheld power tools.

[0004] According to some embodiments of the present disclosure, on the one hand, an embodiment of the present disclosure provides a handheld power tool, including:

[0005] A fixed handle housing;

[0006] A sliding sleeve housing, which is connected to the fixed handle housing, and under the action of an external force, the sliding sleeve housing reciprocally slides on the fixed handle housing along a preset path;

[0007] A load detection component for generating a target electrical signal reflecting the magnitude of a target load according to the target displacement of the sliding sleeve housing; wherein the target displacement is the displacement of the sliding sleeve housing along a preset direction on the preset path, and there is a preset mapping relationship between the target displacement and the magnitude of the target load. The target load is the resistance exerted by the workpiece being processed by the handheld power tool on the sliding sleeve housing, and the resistance is determined by the physical properties of the workpiece being processed, and the physical properties include at least one of weight, material, thickness, and processing accuracy requirements;

[0008] A control unit for generating a duty cycle control command according to the target electrical signal;

[0009] A driving device for adjusting the output power of the driving device according to the duty cycle control command, and the driving device is used to drive the handheld power tool to perform a processing operation on the workpiece being processed.

[0010] Preferably, the load detection component includes: a moving part fixedly arranged on the sliding housing; a fixed part arranged on the fixed handle housing, and the fixed part generates the target electrical signal for characterizing the displacement of the moving part based on the change in the displacement of the moving part.

[0011] Preferably, the moving part is a magnet and the fixed part is a Hall sensor. The magnet moves with the sliding housing, and the Hall sensor generates the target electrical signal for characterizing the displacement of the magnet based on the change in the induced magnetic field.

[0012] Preferably, the moving part is a slider of a rheostat, and the fixed part is a carbon film part of the rheostat. The slider of the rheostat slides on the carbon film part of the rheostat as the sliding housing moves. By changing the displacement of the slider of the rheostat, the effective resistance of the carbon film part of the rheostat is adjusted, and the carbon film part of the rheostat generates the target electrical signal for characterizing the displacement of the slider of the rheostat.

[0013] Preferably, the hand-held power tool is an angle grinder, a cutting machine, a grinding wheel machine, an electric drill, an electric saw or a polishing machine.

[0014] According to some embodiments of the present disclosure, on the other hand, the present disclosure also provides a control method for a hand-held power tool, which is applied to the above-mentioned hand-held power tool. The control method includes:

[0015] Detecting the target displacement of the sliding housing of the hand-held power tool; wherein, the target displacement is the displacement in a preset direction on a preset path when the sliding housing reciprocally slides on the fixed handle housing of the hand-held power tool along the preset path;

[0016] Generating a target electrical signal reflecting the magnitude of the target load according to the target displacement; wherein, the target load is the resistance exerted by the workpiece to be processed by the hand-held power tool on the sliding housing, and the resistance is determined by the physical properties of the workpiece to be processed, and the physical properties include at least one of weight, material, thickness and machining accuracy requirements;

[0017] Generating a duty cycle control command according to the target electrical signal;

[0018] Adjusting the output power of the driving device of the hand-held power tool according to the duty cycle control command to drive the hand-held power tool to perform a machining operation on the workpiece to be processed.

[0019] Preferably, the load detection component of the hand-held power tool includes a moving component fixedly arranged on the sliding sleeve housing and a fixed component arranged on the fixed handle housing. When the moving component is a magnet and the fixed component is a Hall sensor, generating the target electrical signal reflecting the magnitude of the target load according to the target displacement includes: generating the target electrical signal according to the magnetic field between the Hall sensor and the magnet; wherein, the magnitude of the magnetic field depends on the distance between the Hall sensor and the magnet.

[0020] Preferably, the load detection component of the hand-held power tool includes a moving component fixedly arranged on the sliding sleeve housing and a fixed component arranged on the fixed handle housing. When the moving component is a slide bar of a rheostat and the fixed component is a carbon film part of the rheostat, generating the target electrical signal reflecting the magnitude of the target load according to the target displacement includes: generating the target electrical signal according to the effective resistance of the carbon film part of the rheostat; wherein, the effective resistance depends on the distance that the slide bar of the rheostat slides on the carbon film part of the rheostat.

[0021] Preferably, when the target displacement is greater than or equal to a preset displacement threshold, if the external force applied to the sliding sleeve housing is removed, the sliding sleeve housing resets to the initial position in the opposite direction of the preset direction, and the control method further includes: obtaining the reset duration of the sliding sleeve housing; when the reset duration is greater than or equal to a preset duration threshold, generating a duty cycle reset instruction; adjusting the output power of the driving device to a preset power according to the duty cycle reset instruction; wherein, the preset power is the output power of the driving device when the target displacement is zero.

[0022] Preferably, the control method further includes: when the reset duration is less than the preset duration threshold, determining that the hand-held power tool is in an idle state, and controlling the driving device to stop rotating; wherein, the idle state is the state when the hand-held power tool is separated from the workpiece.

[0023] The technical solution provided by the embodiments of the present disclosure has at least the following advantages:

[0024] In the hand-held power tool of the present invention, the sliding sleeve housing, the load detection component and the control unit cooperate. The displacement amount of the sliding sleeve housing directly reflects the load characteristics of the workpiece; the load detection component can detect the displacement (target displacement) of the sliding sleeve housing in the preset direction in real time, generate a target electrical signal corresponding to the load magnitude, and realize the accurate quantitative perception of the load; the control unit generates a duty cycle control instruction based on the target electrical signal to adjust the output power of the driving device, so as to actively adjust the output of the hand-held power tool according to the load magnitude of the workpiece.

[0025] The control method of the hand-held power tool of the present invention monitors the displacement of the sliding housing, intelligently senses the load size, and automatically adjusts the output power of the hand-held power tool according to the load size, solving the problems of traditional hand-held power tools relying on manual force application, low safety, and unstable processing quality, realizing efficient, safe, and intelligent processing operations, and effectively extending the equipment life at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] One or more embodiments are exemplarily illustrated by the pictures in the corresponding drawings. These exemplary illustrations do not constitute limitations on the embodiments. Unless otherwise stated, the figures in the drawings do not constitute a scale limitation; in order to more clearly illustrate the technical solutions in the embodiments of the present disclosure or the traditional technologies, the drawings required to be used in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present disclosure. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0027] Figure 1 It is a schematic structural diagram of the hand-held power tool provided by the embodiment of the present disclosure;

[0028] Figure 2 It is a schematic diagram of the relationship between the magnetic field strength H and the output voltage V sensed by the Hall sensor in an embodiment of the present disclosure;

[0029] Figure 3 It is a schematic diagram of the relationship between the displacement D of the slider of the sliding rheostat and the output voltage V in an embodiment of the present disclosure;

[0030] Figure 4 It is a schematic flowchart of the control method of the hand-held power tool provided by the embodiment of the present disclosure.

[0031] Description of the reference numerals in the drawings of the present invention:

[0032] Hand-held power tool 100, fixed handle housing 110, sliding housing 120, load detection component 130, reset device 140.

[0033] The load detection component 130 includes a magnet 131 and a Hall sensor 132 or a slider 133 of a sliding rheostat and a carbon film part 134 of the sliding rheostat.

[0034] The realization, functional features, and advantages of the object of the present invention will be further described with reference to the embodiments and the drawings. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0035] As is known from the background art, the output power of existing handheld power tools is usually fixed or adjusted by a simple mechanical switch, and its output cannot be dynamically adjusted according to the real-time load characteristics of the workpiece to be processed (such as material hardness, thickness, machining accuracy requirements, etc.). Taking a cutting machine as an example, the user needs to apply force according to experience to drive the blade to rotate so as to achieve cutting. When the load of the workpiece to be processed changes, the user needs to manually adjust the force, resulting in low efficiency and low machining accuracy. Moreover, when the user cuts a heavy load, he needs to exert effort to push the tool, and the inertia will cause operation risks, such as tool runaway or rebound.

[0036] The present disclosure provides a handheld power tool and a control method thereof. By means of a load detection component, the displacement (target displacement) of a sliding sleeve in a preset direction is detected in real time, and a target electrical signal corresponding to the load magnitude is generated, so as to achieve precise quantitative perception of the load. The control unit generates a duty cycle control instruction based on the target electrical signal to adjust the output power of the driving device, so as to actively adjust the output of the handheld power tool according to the load magnitude of the workpiece to be processed, solve problems such as the traditional handheld power tool relying on manual force application, low safety, and unstable machining quality, realize efficient, safe, and intelligent machining operations, and effectively extend the service life of the equipment at the same time.

[0037] In the description of the embodiments of the present application, technical terms such as "first" and "second" are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity, specific order or primary-secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "a plurality" is more than two, unless otherwise clearly and specifically defined. Similarly, "multiple groups" means two or more groups (including two groups), and "multiple pieces" means two or more pieces (including two pieces).

[0038] Referring to "embodiments" herein means that a specific feature, structure, or characteristic described in connection with the embodiments can be included in at least one embodiment of the present application. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0039] In the description of the embodiments of the present application, the term "and / or" is merely a description of the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can mean: there is A, there is both A and B at the same time, and there is B. In addition, the character " / " in this article generally represents an "or" relationship between the associated objects before and after.

[0040] In the description of the embodiments of the present application, the orientation or positional relationship indicated by technical terms such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the embodiments of the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation on the embodiments of the present application. For example, if the device or element in the drawing is inverted, then the element described as "below" or "beneath" or "under" or "at the bottom" of other elements or features will be oriented "above" or "at the top" of the other elements or features. Therefore, the term "below" can cover both the upper and lower orientations depending on the context in which the term is used, which will be obvious to those of ordinary skill in the art. The material can be oriented in other ways (e.g., rotated 90 degrees, inverted, flipped), and the spatial relative descriptive terms used herein can be interpreted accordingly.

[0041] In the description of the embodiments of the present application, unless otherwise clearly specified and defined, technical terms such as "mounted", "connected", "coupled", "fixed", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can also be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and can be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to specific circumstances.

[0042] In the corresponding drawings of the embodiments of the present application, for better understanding and convenience of description, the thickness and area of the layers are enlarged. In addition, when describing that a component is "substantially" formed on another component, it means that the component is not formed on the entire surface (or front surface) of the other component, nor on a partial edge of the entire surface.

[0043] In the description of the embodiments of the present application, when a certain component "includes" another component, unless otherwise specified, other components are not excluded, and other components may further be included. The second component is formed or provided above or on the first component, or on the surface of the first component, or on one side of the first component. Embodiments may include those where the first component and the second component are in direct contact, and may also include embodiments where additional components may be present between the first component and the second component such that the first component and the second component are not in direct contact. For simplicity and clarity, various components may be drawn at arbitrary scales. In the drawings, some layers / components may be omitted for simplicity. Unless otherwise specified, forming or providing the second component on the surface of the first component means that the first component and the second component are in direct contact. Among them, the above-mentioned "component" may refer to a layer, a film, a region, a part, a structure, etc.

[0044] The terms used in the description of the various embodiments herein are only for the purpose of describing specific embodiments and are not intended to be limiting. As used in the description of the various embodiments and the appended claims, "the component" is also intended to include the plural form, unless the context clearly indicates otherwise. Among them, the component includes components such as a layer, a film, a region, or a plate.

[0045] The various embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. However, those of ordinary skill in the art can understand that in the various embodiments of the present disclosure, many technical details are provided for the reader to better understand the present disclosure. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solutions claimed in the present disclosure can still be implemented.

[0046] Figure 1 It is a schematic structural diagram of a hand-held power tool provided for an embodiment of the present disclosure.

[0047] Reference Figure 1 , the hand-held power tool 100 includes: a fixed handle housing 110, a sliding sleeve housing 120, and a load detection component 130. The sliding sleeve housing 120 is connected to the fixed handle housing 110. Under the action of an external force, the sliding sleeve housing 120 reciprocally slides on the fixed handle housing 110 along a preset path. The load detection component 130 generates a target electrical signal reflecting the magnitude of the target load according to the target displacement of the sliding sleeve housing 120. The control unit generates a duty cycle control instruction according to the target electrical signal so that the driving device adjusts the output power of the driving device according to the duty cycle control instruction. The driving device is used to drive the hand-held power tool to perform a processing operation on the workpiece.

[0048] Specifically, the sliding sleeve housing 120 is connected to the fixed handle housing 110 through a mechanical structure (such as a slide rail or a roller). The sliding sleeve housing 120 includes a hand-held part. When the user processes an object, a thrust is applied to the sliding sleeve housing 120 through the hand-held part. Under the action of the thrust applied by the user, the sliding sleeve housing 120 slides along a preset path in a preset direction on the fixed handle housing 110. This path is in a straight line direction, and there is a limiting device to prevent the sliding sleeve housing 120 from sliding excessively. When an external force is applied to the sliding sleeve housing 120 by the user, the sliding sleeve moves along the preset path from the initial position to the end position, and the relative distance between the initial position and the end position is the target displacement. Exemplarily, the hand-held power tool 100 further includes a reset device 140. The reset device 140 is used to provide a reset force for the sliding sleeve housing 120. When the thrust applied by the user decreases, the sliding sleeve housing 120 slides in the opposite direction of the preset direction along the preset path under the action of the reset device 140. When the thrust applied by the user decreases to zero, the sliding sleeve housing 120 is reset to the initial position under the action of the reset device 140. When the sliding sleeve housing 120 is reset to the initial position, the target displacement is zero. Among them, the reset device 140 includes, for example, a compression spring, a tension spring, a pneumatic cylinder or a hydraulic cylinder, and the present application does not limit this. The load detection component 130 generates an electrical signal for reflecting the magnitude of the target load according to the target displacement of the sliding sleeve housing 120. The target load is the resistance applied by the object to be processed during the processing of the hand-held power tool 100 to the sliding sleeve housing 120, and the resistance is determined by the physical characteristics of the object to be processed. The physical characteristics include at least one of weight, material, thickness and processing accuracy requirements. The physical characteristics of the object to be processed determine the magnitude of the resistance applied by the object to be processed to the sliding sleeve housing 120. These characteristics will affect the displacement amount of the sliding sleeve housing, thereby affecting the generated electrical signal. There is a preset mapping relationship between the target displacement and the magnitude of the target load. Exemplarily, the preset mapping relationship between the target displacement and the magnitude of the target load is shown in Table 1. Exemplarily, when the hand-held power tool processes the object to be processed X, the target displacement of the sliding sleeve housing is A, then the magnitude of the load corresponding to the object to be processed X is a.

[0049] Table 1

[0050] Preset displacement Preset load A a B b C c ...... ......

[0051] The control unit generates a duty cycle control instruction based on the target electrical signal input by the load detection component, and then adjusts the output power of the driving device, enabling the handheld power tool to dynamically adjust the power output according to the actual load situation. For example, when encountering a large load, the control unit increases the duty cycle of the motor to increase the output power, enabling the tool to complete cutting or grinding tasks more efficiently; while when the load is small, the duty cycle is appropriately reduced to reduce unnecessary energy consumption. This adaptive adjustment mechanism not only improves work efficiency but also prevents excessive power output from accelerating the wear of the motor and other mechanical components, thus effectively extending the service life of the tool.

[0052] In the handheld power tool of the present invention, the sliding sleeve, the load detection component, and the control unit cooperate to achieve the function of actively adjusting the output power according to the load size of the workpiece being processed. Specifically, the displacement amount of the sliding sleeve directly reflects the load characteristics of the workpiece being processed. The load detection component can detect the displacement (target displacement) of the sliding sleeve in a preset direction in real time and generate a target electrical signal corresponding to the load size, enabling the handheld power tool to perceive the current working load in real time. Thus, accurate quantitative perception of the load is achieved, enabling the handheld power tool to dynamically adjust the power output according to the actual load situation. This adaptive adjustment mechanism not only improves work efficiency but also prevents excessive power output from accelerating the wear of the motor and other mechanical components, thus effectively extending the service life of the tool. In addition, since the present invention can automatically adjust the output power when the load changes, the operation difficulty and potential risks for the user are reduced. For example, in heavy cutting operations, if the tool suddenly loses load (such as cutting through air), the control unit can quickly identify this situation and immediately stop the machine to prevent misoperations or other safety hazards caused by inertia.

[0053] The following will describe the embodiments of the present disclosure in more detail with reference to the accompanying drawings.

[0054] In a possible implementation, the load detection component 130 includes: a moving component fixedly arranged on the sliding sleeve 120; a fixed component arranged on the fixed handle housing 110, and the fixed component generates a target electrical signal for characterizing the displacement of the moving component based on the change in the displacement of the moving component.

[0055] The present invention proposes two specific implementation methods for the load detection component 130, namely the design based on Hall sensors and the design based on sliding rheostats. These two embodiments detect the displacement of the sliding sleeve through different physical principles and generate a target electrical signal characterizing the displacement. The following is a detailed description of these two embodiments:

[0056] Embodiment 1: Load Detection Component Based on Hall Sensor

[0057] SeeFigure 1 As shown, in an implementation provided in this embodiment, the moving component is the magnet 131, and the fixed component is the Hall sensor 132. The magnet 131 moves with the sliding housing 120. Based on the change in the induced magnetic field, the Hall sensor 132 generates a target electrical signal for characterizing the displacement of the magnet 131.

[0058] Specifically, the Hall sensor 132 is a sensor based on the Hall effect, which can detect the change in the magnetic field and convert it into an electrical signal. Optionally, the Hall sensor 132 can be fixed at one end of the fixed handle housing 110 away from the reset device 140, or the Hall sensor 132 can be fixed at one end of the fixed handle housing 110 close to the reset device 140. The following will explain these two cases separately.

[0059] When the Hall sensor 132 is fixed at one end of the fixed handle housing 110 away from the reset device 140, in the initial state, there is a certain initial distance D1 between the magnet 131 and the Hall sensor 132. The Hall sensor 132 detects a reference magnetic field intensity H0 and outputs a corresponding reference voltage V0. When the user applies a thrust to the tool, the sliding housing 120 moves in the preset direction, driving the magnet 131 closer to the Hall sensor 132; the Hall sensor 132 detects the change in the magnetic field intensity H, and the output voltage V changes accordingly. Exemplarily, the relationship between the magnetic field intensity H and the output voltage V is output as Figure 2 As shown, when the distance between the magnet 131 and the Hall sensor 132 is D2, the Hall sensor 132 detects a magnetic field intensity of H1 and outputs a corresponding voltage V1, that is, the closer the magnet 131 is to the Hall sensor 132, the higher the magnetic field intensity H and the higher the output voltage V. The output voltage V is transmitted to the control unit, and the control unit generates a corresponding duty cycle control instruction according to the output voltage V to adjust the output power of the driving device. In this implementation, the displacement of the sliding housing 120 is proportional to the output voltage V.

[0060] When the Hall sensor 132 is fixed to one end of the fixed handle housing 110 near the reset device 140, in the initial state, a certain initial distance D3 is maintained between the magnet 131 and the Hall sensor 132. The Hall sensor 132 detects a reference magnetic field intensity H2 and outputs a corresponding reference voltage V2. When the user applies a thrust force to the tool, the sliding sleeve 120 moves in a preset direction, driving the magnet 131 away from the Hall sensor 132; the Hall sensor 132 detects a change in the magnetic field intensity H, and the output voltage V changes accordingly. That is, the farther the magnet 131 is from the Hall sensor 132, the lower the magnetic field intensity H, and the lower the output voltage V. The output voltage V is transmitted to the control unit, and the control unit generates a corresponding duty cycle control command according to the output voltage V to adjust the output power of the driving device. In this implementation, the displacement of the sliding sleeve 120 is inversely proportional to the output voltage V.

[0061] Optionally, in another implementation provided in this embodiment, the moving component is the Hall sensor 132, the fixed component is the magnet 131, the Hall sensor 132 moves with the sliding sleeve 120, and the Hall sensor 132 generates a target electrical signal for characterizing the displacement of the Hall sensor 132 based on the change in the induced magnetic field.

[0062] Optionally, the magnet 131 can be fixed to one end of the fixed handle housing 110 far from the reset device 140, or the magnet 131 can be fixed to one end of the fixed handle housing 110 near the reset device 140. The following will separately describe these two cases.

[0063] When the magnet 131 is fixed to one end of the fixed handle housing 110 far from the reset device 140, in the initial state, a certain distance D4 is maintained between the Hall sensor 132 and the magnet 131. At this time, the magnetic field intensity H detected by the Hall sensor 132 is relatively low, and the output electrical signal is also relatively low. When the user applies a thrust force to the sliding sleeve 120, the sliding sleeve 120 moves in a preset direction, driving the Hall sensor 132 to move accordingly, and the Hall sensor 132 gradually approaches the magnet 131. The magnetic field intensity H changes with the change in the distance between the Hall sensor 132 and the magnet 131. The Hall sensor 132 outputs a voltage V that changes accordingly according to the detected change in the magnetic field intensity H. The output voltage V reflects the current displacement amount of the sliding sleeve 120, thereby indirectly characterizing the load size of the workpiece being processed. Specifically, the closer the Hall sensor 132 is to the magnet 131, the higher the magnetic field intensity H, and the higher the output voltage V output by the Hall sensor 132. The output voltage V is transmitted to the control unit, and the control unit generates a corresponding duty cycle control command according to the received output voltage V to adjust the output power of the driving device. In this implementation, the displacement of the sliding sleeve 120 is directly proportional to the output voltage V.

[0064] When the magnet 131 is fixed to one end of the fixed handle housing 110 near the reset device 140, in the initial state, a certain distance D5 is maintained between the Hall sensor 132 and the magnet 131. At this time, the magnetic field intensity H detected by the Hall sensor 132 is relatively high, and the output electrical signal is also relatively high. When the user applies a thrust to the sliding sleeve 120, the sliding sleeve 120 moves in the preset direction, driving the Hall sensor 132 to move accordingly. The Hall sensor 132 gradually moves away from the magnet 131. The magnetic field intensity H changes with the change in the distance between the Hall sensor 132 and the magnet 131. The Hall sensor 132 outputs a voltage V that changes according to the detected change in the magnetic field intensity H. The output voltage V reflects the current displacement of the sliding sleeve 120, thereby indirectly characterizing the load size of the workpiece being processed. Specifically, the farther the Hall sensor 132 is from the magnet 131, the lower the magnetic field intensity H, and the lower the output voltage V output by the Hall sensor 132. The output voltage V is transmitted to the control unit, and the control unit generates a corresponding duty cycle control instruction based on the received output voltage V to adjust the output power of the drive device. In this implementation, the displacement of the sliding sleeve 120 is inversely proportional to the output voltage V.

[0065] Based on the above technical solution, the Hall sensor can accurately detect the change in the magnetic field intensity, thereby providing high-precision displacement measurement; and the Hall effect responds quickly, enabling displacement detection and feedback to be completed in a short time; there is no need for direct contact between the magnet and the Hall sensor, reducing mechanical wear and the risk of failure.

[0066] Embodiment 2: Load detection component based on a sliding rheostat

[0067] See Figure 1 As shown, in a possible implementation, the moving part is the sliding rheostat rod 133, and the fixed part is the sliding rheostat carbon film part 134. The sliding rheostat rod 133 slides on the sliding rheostat carbon film part 134 as the sliding sleeve 120 moves. By changing the displacement of the sliding rheostat rod 133, the effective resistance of the sliding rheostat carbon film part 134 is adjusted. Based on the effective resistance, the sliding rheostat carbon film part 134 generates a target electrical signal for characterizing the displacement of the sliding rheostat rod 133.

[0068] Specifically, in the initial state, the slider 133 of the rheostat is located at the initial position D6 of the carbon film portion 134 of the rheostat. In the static state, the carbon film portion 134 of the rheostat outputs a reference resistance corresponding to a reference voltage. When the user applies a thrust to the tool, the sliding housing 120 moves in a preset direction, driving the slider 133 of the rheostat to slide on the carbon film portion 134 of the rheostat; the effective resistance of the carbon film portion 134 of the rheostat changes with the displacement D of the slider 133 of the rheostat, and the output voltage also changes accordingly; the output voltage signal is transmitted to the control unit, and the control unit generates a corresponding duty cycle control command according to the voltage signal.

[0069] In an implementation provided in this embodiment, the resistance of the part of the carbon film portion 134 of the rheostat that the slider 133 of the rheostat passes through can be used as the effective resistance of the rheostat. Specifically, in the initial state, the slider 133 of the rheostat is located at the initial position of the carbon film portion 134 of the rheostat, and the carbon film portion 134 of the rheostat outputs a reference resistance corresponding to a reference voltage; when the user applies a thrust to the tool, the sliding housing 120 moves in a preset direction, driving the slider 133 of the rheostat to slide on the carbon film portion 134 of the rheostat. As the slider 133 of the rheostat moves, the effective resistance of the carbon film portion 134 of the rheostat changes. Specifically, the longer the part that the slider 133 of the rheostat passes through, the greater the effective resistance. The carbon film portion 134 of the rheostat outputs different resistance values according to the displacement D of the slider 133 of the rheostat, and thus generates a corresponding output voltage V. In this implementation, the displacement D of the slider 133 of the rheostat is proportional to the output voltage V. Refer to Figure 3 As shown, when the displacement of the slider 133 of the rheostat is d1, the effective resistance of the carbon film portion 134 of the rheostat is R1, and the carbon film portion 134 of the rheostat outputs a corresponding voltage V3; when the user increases the thrust applied to the tool, the displacement of the slider 133 of the rheostat increases to d2, the effective resistance of the carbon film portion 134 of the rheostat is R2, and the carbon film portion 134 of the rheostat outputs a corresponding voltage V4. The carbon film portion 134 of the rheostat transmits the output voltage V to the control unit, and the control unit generates a corresponding duty cycle control command according to the received output voltage V to adjust the output power of the driving device.

[0070] In another implementation provided by this embodiment, the resistance of the unscanned part of the sliding rheostat carbon film part 134 by the sliding rheostat rod 133 can be used as the effective resistance of the sliding rheostat. Specifically, in the initial state, the sliding rheostat rod 133 is located at the initial position of the sliding rheostat carbon film part 134, and the sliding rheostat carbon film part 134 outputs a reference resistance corresponding to a reference voltage. When the user applies a thrust to the tool, the sliding housing 120 moves in a preset direction, driving the sliding rheostat rod 133 to slide on the sliding rheostat carbon film part 134. As the sliding rheostat rod 133 moves, the effective resistance of the sliding rheostat carbon film part 134 changes. Specifically, the longer the scanned part of the sliding rheostat rod 133 is, the shorter the unscanned part is, and the smaller the effective resistance is. The sliding rheostat carbon film part 134 outputs different resistance values according to the position of the sliding rheostat rod 133, thereby generating a corresponding output voltage V. In this implementation, the displacement D of the sliding rheostat rod 133 is inversely proportional to the output voltage V. The output voltage V is transmitted to the control unit, and the control unit generates a corresponding duty cycle control command according to the received output voltage V to adjust the output power of the driving device.

[0071] Based on the above technical solutions, accurate load sensing and dynamic power adjustment can be achieved, improving work efficiency. Moreover, the design of the sliding rheostat is relatively simple and easy to integrate into the handheld power tool, without the need for complex sensors or external devices. Compared with other complex load detection solutions, the cost of the sliding rheostat is lower, which helps to reduce the overall manufacturing cost.

[0072] Preferably, the handheld power tool is an angle grinder, a cutting machine, a grinding wheel, a drill, a saw or a polishing machine.

[0073] In the hand-held power tool of the present invention, the sliding housing, the load detection component, and the control unit cooperate to achieve the function of actively adjusting the output power according to the load size of the workpiece to be processed. Specifically, the displacement of the sliding housing directly reflects the load characteristics of the workpiece to be processed. The load detection component can detect the displacement (target displacement) of the sliding housing in the preset direction in real time and generate a target electrical signal corresponding to the load size, enabling the hand-held power tool to sense the current working load in real time. Thus, accurate quantitative perception of the load is achieved. Based on this target electrical signal, the control unit generates a duty cycle control instruction to adjust the output power of the driving device, enabling the hand-held power tool to dynamically adjust the power output according to the actual load condition. This adaptive adjustment mechanism not only improves work efficiency but also prevents excessive power output from accelerating the wear of the motor and other mechanical components, thereby effectively extending the service life of the tool. In addition, since the present invention can automatically adjust the output power when the load changes, the operation difficulty and potential risks of the user are reduced. For example, in heavy cutting operations, if the tool suddenly loses load (such as cutting into empty space), the control unit can quickly identify this situation and immediately stop the machine to prevent misoperations or other safety hazards caused by inertia.

[0074] Correspondingly, another embodiment of the present disclosure also provides a control method for a hand-held power tool, which can be applied to the hand-held power tool provided in the above embodiment. The following will detail the control method for the hand-held power tool provided in another embodiment of the present disclosure in conjunction with the accompanying drawings. For the same or corresponding parts as those in the previous embodiment, reference can be made to the corresponding description in the previous embodiment, and the following will not be elaborated in detail.

[0075] Figure 4 The schematic flowchart of a control method for a hand-held power tool provided by an embodiment of the present application is shown, as Figure 4 shown, the control method for the above-mentioned hand-held power tool includes the following solutions:

[0076] S410: Detect the target displacement of the sliding housing of the hand-held power tool;

[0077] S420: Generate a target electrical signal reflecting the size of the target load according to the target displacement;

[0078] S430: Generate a duty cycle control instruction according to the target electrical signal;

[0079] S440: Adjust the output power of the driving device of the hand-held power tool according to the duty cycle control instruction to drive the hand-held power tool to perform a processing operation on the workpiece to be processed.

[0080] When a user uses a hand-held power tool to process an object, a thrust is applied to the sliding housing through the hand-held part. Under the action of the thrust applied by the user, the sliding housing moves along a preset path from the initial position to the end position, and the relative distance between the initial position and the end position is the target displacement. The load detection component detects the target displacement of the sliding housing in real time and generates a target electrical signal corresponding to the load size, enabling real-time perception of the target load of the currently processed object. Among them, the target load is the resistance exerted by the processed object during the processing of the hand-held power tool on the sliding housing, and the resistance is determined by the physical characteristics of the processed object. The physical characteristics include at least one of weight, material, thickness, and processing accuracy requirements. Based on the target electrical signal, the control unit generates a duty cycle control instruction to adjust the output power of the driving device, so as to dynamically adjust the power output of the hand-held power tool according to the actual load situation.

[0081] Specifically, after receiving the target electrical signal generated by the load detection component, the control unit first analyzes the received target electrical signal to determine the size of the target load; according to the analysis result, the control unit calculates the PWM (pulse width modulation) duty cycle corresponding to the target load. The duty cycle determines the proportion of the high-level time in each cycle, thereby affecting the average voltage and current of the motor, and further adjusting its output power. For example, assuming the duty cycle is 80%, then in one cycle, the time when the signal remains high accounts for 80% of the entire cycle. Specifically, a larger load requires a higher duty cycle to provide more energy, while a smaller load requires a lower duty cycle to save energy consumption. When the load increases, the control unit generates a duty cycle control instruction and sends it to the three-phase inverter to increase the duty cycle of the PWM signal, so that the inverter provides a higher voltage and current to the motor, thereby increasing the output power of the motor. It can be understood that the inverter usually consists of six power switching devices (such as MOSFET or IGBT), which respectively control the on-off states of the three-phase windings. These switching devices quickly switch according to the duty cycle of the PWM signal to generate corresponding three-phase AC voltage waveforms to provide voltage and current for the motor.

[0082] In a possible implementation, the load detection component of the hand-held power tool includes a moving part fixedly arranged on the sliding housing and a fixed part arranged on the fixed handle housing. When the moving part is a magnet and the fixed part is a Hall sensor, according to the target displacement, a target electrical signal reflecting the size of the target load is generated, including: generating a target electrical signal according to the magnetic field between the Hall sensor and the magnet; wherein, the size of the magnetic field depends on the distance between the Hall sensor and the magnet. It should be understood that in another implementation provided in this embodiment, the moving part can be a Hall sensor and the fixed part can be a magnet. For the specific implementation method, refer to a hand-held power tool provided in the previous embodiment of the present disclosure, which will not be elaborated here.

[0083] In a possible implementation, the load detection component of the hand-held power tool includes a moving part fixedly arranged on the sliding sleeve and a fixed part arranged on the fixed handle housing. When the moving part is the slider of the sliding rheostat and the fixed part is the carbon film part of the sliding rheostat, according to the target displacement, generating a target electrical signal reflecting the magnitude of the target load includes: generating the target electrical signal according to the effective resistance of the carbon film part of the sliding rheostat; wherein, the effective resistance depends on the distance that the slider of the sliding rheostat slides on the carbon film part of the sliding rheostat. For the specific implementation, refer to a hand-held power tool provided in the previous embodiment of the present disclosure, which will not be elaborated here.

[0084] In a possible implementation, when the target displacement is greater than or equal to the preset displacement threshold, if the external force applied to the sliding sleeve is removed, the sliding sleeve returns to the initial position in the opposite direction of the preset direction, and the control method further includes: obtaining the reset duration of the sliding sleeve; when the reset duration is greater than or equal to the preset duration threshold, generating a duty cycle reset command; adjusting the output power of the driving device to the preset power according to the duty cycle reset command; when the reset duration is less than the preset duration threshold, determining that the hand-held power tool is in an unloaded state, and controlling the driving device to stop rotating.

[0085] Specifically, when the load of the workpiece to be processed decreases, the sliding sleeve slides in the opposite direction of the preset direction under the action of the reset device, the target displacement of the sliding sleeve decreases, the target electrical signal output by the load detection component decreases, the control unit generates a duty cycle decrease instruction, and controls the output power of the driving device to decrease. When the load disappears, the sliding sleeve returns to the initial position under the action of the reset device. In the embodiments of the present disclosure, a preset displacement threshold is defined. When the target displacement is greater than or equal to the preset displacement threshold, it is considered that the target load of the current workpiece to be processed is a heavy load. During the processing of the workpiece to be processed, if the user removes the external force applied to the sliding sleeve, the sliding sleeve resets to the initial position in the opposite direction of the preset direction. Among them, the factors causing the reset of the sliding sleeve include many aspects. For example, when the heavy load part of the workpiece to be processed is completed and the target load suddenly changes from a heavy load to a light load, the user gradually removes the external force applied to the sliding sleeve, or at the moment when the processing of the workpiece to be processed is completed, the user removes the external force applied to the sliding sleeve, which will cause the sliding sleeve to reset to the initial position in the opposite direction of the preset direction. The control unit can determine the reason for the reset of the sliding sleeve by the length of the reset duration of the sliding sleeve. Specifically, if the reset duration is greater than or equal to the preset duration threshold, it indicates that the user gradually removes the external force applied to the sliding sleeve, that is, the factor causing the reset of the sliding sleeve is that the heavy load part of the current workpiece to be processed is completed and the target load suddenly changes from a heavy load to a light load; if the reset duration is less than the preset duration threshold, it indicates that the user suddenly removes the external force applied to the sliding sleeve, that is, the factor causing the reset of the sliding sleeve is that the processing of the workpiece to be processed is completed and the hand-held power tool is in an unloaded state. Among them, the unloaded state is the state when the hand-held power tool is separated from the workpiece to be processed. When the control unit determines that the factor causing the reset of the sliding sleeve is that the heavy load part of the current workpiece to be processed is completed and the target load suddenly changes from a heavy load to a light load, it generates a duty cycle reset instruction; according to the duty cycle reset instruction, the output power of the driving device is adjusted to the preset power to prevent excessive power output from accelerating the wear of the motor and other mechanical components, thereby effectively extending the service life of the tool. Among them, the preset power is the output power of the driving device when the target displacement is zero. When the control unit determines that the factor causing the reset of the sliding sleeve is that the processing of the workpiece is completed and the hand-held power tool is in an unloaded state, it controls the driving device to stop rotating to prevent misoperation or other safety hazards caused by inertia.

[0086] The control method of the hand-held power tool of the present invention monitors the displacement of the sliding sleeve, intelligently senses the load size, and automatically adjusts the output power of the hand-held power tool according to the load size, solving the problems of traditional hand-held power tools relying on manual force application, low safety, and unstable processing quality, realizing efficient, safe, and intelligent processing operations, and effectively extending the service life of the equipment at the same time.

[0087] Those of ordinary skill in the art can understand that the above embodiments are specific examples for implementing the present disclosure. In actual applications, various changes can be made to them in form and details without departing from the spirit and scope of the present disclosure. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present disclosure. Therefore, the protection scope of the present disclosure should be subject to the scope defined by the claims.

Claims

1. A hand-held power tool, characterized in that, Comprising: A fixed handle housing; A sliding sleeve housing, which is connected to the fixed handle housing, and under the action of an external force, the sliding sleeve housing reciprocates along a preset path on the fixed handle housing; A load detection component for generating a target electrical signal reflecting the magnitude of a target load according to the target displacement of the sliding sleeve housing; wherein, the target displacement is the displacement of the sliding sleeve housing along a preset direction on the preset path, and there is a preset mapping relationship between the target displacement and the magnitude of the target load, the target load is the resistance exerted on the sliding sleeve housing by the workpiece to be processed by the hand-held power tool, and the resistance is determined by the physical properties of the workpiece to be processed, and the physical properties include at least one of weight, material, thickness, and machining accuracy requirements; A control unit for generating a duty cycle control command according to the target electrical signal; A driving device for adjusting the output power of the driving device according to the duty cycle control command, and the driving device is used to drive the hand-held power tool to perform a machining operation on the workpiece to be processed.

2. The hand-held power tool according to claim 1, characterized in that: The load detection component includes: a moving part fixedly arranged on the sliding sleeve housing; A fixed part arranged on the fixed handle housing, and the fixed part generates the target electrical signal for characterizing the displacement of the moving part based on the change in the displacement of the moving part.

3. The hand-held power tool according to claim 2, wherein: The moving part is a magnet, the fixed part is a Hall sensor, the magnet moves with the sliding sleeve housing, and the Hall sensor generates the target electrical signal for characterizing the displacement of the magnet based on the change in the induced magnetic field.

4. The hand-held power tool according to claim 2, wherein: The moving part is a slider of a slide rheostat, the fixed part is a carbon film part of the slide rheostat, the slider of the slide rheostat slides on the carbon film part of the slide rheostat as the sliding sleeve housing moves, and by changing the displacement of the slider of the slide rheostat, the effective resistance of the carbon film part of the slide rheostat is adjusted, and the carbon film part of the slide rheostat generates the target electrical signal for characterizing the displacement of the slider of the slide rheostat based on the effective resistance.

5. The hand-held power tool according to any one of claims 1 to 4, wherein: The hand-held power tool is an angle grinder, a cutting machine, a grinding wheel machine, an electric drill, an electric saw or a polishing machine.

6. A control method for a hand-held power tool, characterized in that, Applied to the hand-held power tool according to any one of claims 1 to 5, the control method includes: Detecting the target displacement of the sliding sleeve housing of the hand-held power tool; wherein, the target displacement is the displacement along a preset direction on the preset path when the sliding sleeve housing reciprocates along the preset path on the fixed handle housing of the hand-held power tool. Generate a target electrical signal reflecting the magnitude of the target load according to the target displacement; wherein, the target load is the resistance exerted by the workpiece being processed by the handheld power tool on the sliding housing, and the resistance is determined by the physical properties of the workpiece being processed, and the physical properties include at least one of weight, material, thickness, and machining accuracy requirements; Generate a duty cycle control command according to the target electrical signal; Adjust the output power of the drive device of the handheld power tool according to the duty cycle control command to drive the handheld power tool to perform a machining operation on the workpiece being processed.

7. The control method according to claim 6, characterized in that, The load detection component of the handheld power tool includes a moving component fixedly arranged on the sliding housing and a fixed component arranged on the fixed handle housing. When the moving component is a magnet and the fixed component is a Hall sensor, the generating of the target electrical signal reflecting the magnitude of the target load according to the target displacement includes: Generate the target electrical signal according to the magnetic field between the Hall sensor and the magnet; wherein, the magnitude of the magnetic field depends on the distance between the Hall sensor and the magnet.

8. The control method according to claim 6, characterized in that The load detection component of the handheld power tool includes a moving component fixedly arranged on the sliding housing and a fixed component arranged on the fixed handle housing. When the moving component is a slider of a rheostat and the fixed component is a carbon film part of the rheostat, the generating of the target electrical signal reflecting the magnitude of the target load according to the target displacement includes: Generate the target electrical signal according to the effective resistance of the carbon film part of the rheostat; wherein, the effective resistance depends on the distance that the slider of the rheostat slides on the carbon film part of the rheostat.

9. The control method according to claim 6, characterized in that, When the target displacement is greater than or equal to a preset displacement threshold, if the external force applied to the sliding housing is removed, the sliding housing resets to the initial position in the opposite direction of the preset direction, and the control method further includes: obtaining the reset duration of the sliding housing; Generate a duty cycle reset command when the reset duration is greater than or equal to a preset duration threshold; Adjust the output power of the drive device to a preset power according to the duty cycle reset command; wherein, the preset power is the output power of the drive device when the target displacement is zero.

10. The control method according to claim 9, wherein The control method further includes: When the reset duration is less than the preset duration threshold, determine that the handheld power tool is in an unloaded state, and control the drive device to stop rotating; wherein, the unloaded state is the state when the handheld power tool is separated from the workpiece being processed.

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