Torque-adjustable electric screw driver and control method of electric screw driver

Abstract

The invention relates to the technical field of intelligent tools, and particularly provides a torque-adjustable electric screw driver and a control method of the electric screw driver. The control method comprises the steps that in response to a motor starting instruction, a state reference value used for judging the torque state of an output shaft is obtained in real time, the state reference value comprises rotation speed and angular displacement data; a comparison result of the state reference value and a theoretical value is obtained, whether the comparison result is larger than a preset stalling threshold value or not is judged, and if yes, an adjusting button starting instruction is output; and judging whether a difference value between the state reference value and the theoretical value is smaller than a preset normal threshold value or not, and if yes, outputting an adjustment stop instruction. According to the application, the user experience and the working efficiency can be remarkably improved, and particularly, accurate torque matching can be realized when the torque needs to be accurately controlled or under an unknown resistance working condition, so that screws or materials are prevented from being damaged.

Description

Technical Field

[0001] The present application relates to the technical field of intelligent tools, and in particular to an electric screwdriver with adjustable torque and an electric screwdriver control method. Background Art

[0002] Electric screwdrivers are tools used to drive screws. Traditional electric screwdrivers have a fixed torque when screwing in and out, which results in the screw not being able to penetrate the material effectively or the installation of tight screws being impossible to remove.

[0003] Mechanical torque adjustment structures have begun to be used in related electric screwdrivers. By selecting different torque gears, the torque of the electric screwdriver during operation can meet the requirements of screwing in or out the screws. However, the existing mechanical torque adjustment structures are usually designed with multiple gears and require the user to adjust the torque size independently. They cannot automatically adjust to the matching torque size according to the current screw status or the material being screwed in. Summary of the Invention

[0004] The primary purpose of the present application is to solve at least one of the above problems and provide an electric screwdriver with adjustable torque, comprising:

[0005] A housing, wherein an outer surface of the housing is provided with an adjustment port extending along the length direction;

[0006] A torque transmission assembly, comprising a gear sleeve and a planetary gear set, wherein the upper surface of the gear sleeve is provided with a plurality of raised limiting portions, the gear sleeve is rotatably disposed in the housing, and the planetary gear set is rotatably disposed inside the gear sleeve and meshes with the gear sleeve;

[0007] A mechanical twist adjustment assembly, comprising a connecting head, an adjusting rod, an adjusting ring, a pressure ring, an operating member, several elastic members and corresponding limiting beads, a step being formed in the middle of the connecting head, the limiting beads being rotatably embedded in the surface of the step, the several elastic members being arranged on the same side of the pressure ring, the adjusting ring and the pressure ring being stacked in sequence from top to bottom on the connecting head, the adjusting rod being horizontally connected to the adjusting ring and extending out of the adjusting port, the operating member being connected to the adjusting rod on the outside of the housing; when the adjusting rod moves along the adjusting port, the adjusting ring moves synchronously; the connecting head being sleeved on the gear sleeve, the limiting beads being in contact with the upper surface of the gear sleeve;

[0008] a first drive motor, the first drive motor being disposed in the housing and drivingly connected to the planetary gear set;

[0009] A second driving motor is connected to the adjusting ring in a transmission manner to drive the adjusting ring to move up and down.

[0010] Optionally, it further includes a driven rack and a driving gear, wherein the driven rack is fixed on the outside of the operating member, the driving gear is transmission-connected to the second drive motor, and the driving gear is meshed with the driven rack.

[0011] Optionally, a plurality of transverse slots are further provided in the middle of the adjustment port.

[0012] Optionally, the adjustment ring is provided with a limiting groove extending in the circumferential direction, and the adjustment rod is arranged in the limiting groove.

[0013] Optionally, the operating member is configured as a manual operating ring, the manual operating ring is sleeved on the outer side of the shell, and the adjusting rod is connected to the inner side wall of the manual operating ring.

[0014] On the other hand, a control method for an electric screwdriver provided to meet one of the objectives of the present application is applied to the torque-adjustable electric screwdriver as described above, and the control method comprises the following steps:

[0015] In response to a motor start instruction, a state reference value for determining a torque state of an output shaft is acquired in real time, the state reference value including rotation speed and angular displacement data;

[0016] Obtaining a comparison result between the state reference value and the theoretical value, and determining whether the comparison result is greater than a preset stall threshold, and if so, outputting a start torque adjustment instruction;

[0017] It is determined whether the difference between the state reference value and the theoretical value is less than a preset normal threshold value, and if so, a stop torque adjustment instruction is output.

[0018] Optionally, after obtaining the comparison result between the state reference value and the theoretical value and determining whether the comparison result is greater than a preset stall threshold, and outputting a start torque adjustment instruction if so, the following steps may also be included:

[0019] The corresponding adjusted speed is searched in the speed reference table according to the current torque value, and the stall threshold is updated according to the adjusted speed.

[0020] Optionally, the determining whether the difference between the state reference value and the theoretical value is less than a preset normal threshold value further includes the following steps:

[0021] If the difference between the state reference value and the theoretical value is greater than a preset normal threshold, it is determined whether the current torque value meets the maximum value, and if so, a motor stop command is output.

[0022] Optionally, obtaining a comparison result between the state reference value and the theoretical value, and determining whether the comparison result is greater than a preset stall threshold, and outputting a start torque adjustment instruction if so, includes the following steps:

[0023] Obtain a time value when the comparison result is greater than a preset stop threshold value, determine whether the time value is greater than a preset confirmation time value, and if so, output a start adjustment instruction.

[0024] Optionally, the start-up adjustment instruction includes a step-by-step adjustment mode and / or a linear adjustment mode; the step-by-step adjustment mode is configured to output a motor start signal of the same duration according to a preset time interval, and the linear adjustment mode is configured to continuously output a motor start signal; wherein the rotational speed of the motor start signal is a fixed value.

[0025] The technical solution of this application has many advantages, including but not limited to the following:

[0026] This application firstly provides a planetary gear set on the torque transmission assembly, so that the output of the first drive motor is transmitted to the other end of the planetary gear set more smoothly and with greater torque. Secondly, a mechanical torque adjustment assembly is provided on the torque transmission assembly. By manually operating the adjustment lever or using the second drive motor to move the adjustment ring along the length direction of the electric screwdriver, pressure is applied to the pressure ring. The elastic member provided on the pressure ring is compressed or released, thereby applying different forces to the limit bead embedded in the connector. During normal operation, the pressure of the elastic member causes the limit bead to be confined between the limit parts at the top of the gear sleeve. The output of the first drive motor is completely transmitted through the planetary gear set. When the torque is insufficient, the output shaft is stuck, the planetary gear set drives the gear sleeve in reverse, and the limit part at the top of the gear sleeve breaks through the limit bead and slips.

[0027] In addition, the present application also proposes a control method for an electric screwdriver, which comprehensively judges the output shaft state by real-time monitoring of the rotational speed and angular displacement data of the output shaft at startup, making the judgment more accurate; then, by obtaining the comparison result of the state reference value and the theoretical value, and judging whether the comparison result is greater than a preset stop threshold, the comparison result of the state reference value and the theoretical value is indirectly used to judge whether the output shaft torque is insufficient, which can avoid the influence of the state reference value fluctuation on the judgment and further improve the accuracy. When it is determined that the torque is insufficient, a start torque adjustment command is output, and the tool enters the torque increase state until it is indirectly judged that the output shaft has resumed normal operation through the difference between the state reference value and the theoretical value. It is then judged that the torque has met the requirements and a stop torque adjustment command is output. The present application combines traditional electric tools with modern sensing and control technology, which can significantly improve user experience and work efficiency. In particular, when precise torque control is required or when facing unknown resistance conditions, accurate torque matching can be achieved to avoid damage to screws or materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a three-dimensional structural diagram of a torque-adjustable electric screwdriver in the present application;

[0029] Figure 2 is an exploded schematic diagram of a torque-adjustable electric screwdriver in the present application;

[0030] Figure 3 This is a diagram of the internal structure of a torque-adjustable electric screwdriver in this application;

[0031] Figure 4 This is a flow chart of an embodiment of a control method for an electric screwdriver in the present application;

[0032] Description of reference numerals:

[0033] 10. Housing; 11. Adjustment port; 20. Gear sleeve; 201. Limiting portion; 21. Planetary gear set; 30. Connector; 31. Adjustment rod; 32. Adjustment ring; 321. Limiting groove; 33. Operating member; 34. Pressing ring; 35. Elastic member; 36. Limiting bead; 40. First drive motor; 41. Second drive motor; 42. Driven rack; 43. Driving gear. DETAILED DESCRIPTION

[0034] The following describes in detail embodiments of the present application. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application and are not to be construed as limiting the present application.

[0035] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise specified, "multiple" means two or more.

[0036] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0037] The technical solution of the present application is applicable to the field of intelligent tool technology, and is particularly applicable to electric screwdriver tools. Electric screwdrivers are usually used in the disassembly and assembly of screws. In some application scenarios where screws need to be driven into materials, due to insufficient torque or large screw size, the screws get stuck after slipping on the surface of the material, especially wooden materials and some thicker, longer screws or screws with a head design that require a larger driving force. When removing some screws with a larger torque, a larger torque is also required to remove them. Ordinary electric screwdrivers usually have a smaller torque and are unable to cope with this task.

[0038] Although torque-adjustable electric screwdrivers have appeared in related products, existing torque-adjustable electric screwdrivers usually rely on the user's experience to adjust the torque. When the torque exceeds the adaptability range of the current scenario, it will lead to adverse consequences. For example, the sudden application of excessive torque will cause the screwdriver head to slip in the screw slot, causing the slot to be rounded, deformed, or even completely damaged, and ultimately unable to be disassembled; or in woodworking, excessive torque will cause the tail of the screw to excessively squeeze the wood fibers, causing the wood to split along the grain direction. Therefore, choosing the right torque is crucial. The method of users manually adjusting the torque in sequence is also cumbersome and inconvenient in actual use.

[0039] In this context, the technical solution of the present application can be applied to an electric screwdriver with adjustable torque, such as Figure 1 and Figure 3 As shown, Figure 1A torque-adjustable electric screwdriver is proposed, comprising a housing 10, a torque transmission assembly, a mechanical torque adjustment assembly, a first drive motor 40 and a second drive motor 41; the outer surface of the housing 10 is provided with an adjustment port 11 extending along the length direction; the torque transmission assembly comprises a gear sleeve 20 and a planetary gear set 21, the upper surface of the gear sleeve 20 is provided with several raised limiting portions 201, the gear sleeve 20 is rotatably arranged in the housing 10, the planetary gear set 21 is rotatably arranged inside the gear sleeve 20, and meshes with the gear sleeve 20; the mechanical torque adjustment assembly comprises a connecting head 30, an adjusting rod 31, an adjusting ring 32, a pressure ring 34, an operating member 33, several elastic members 35 and corresponding limiting beads 36, the middle part of the connecting head 30 forms a step, and the limiting beads 36 are rotatably embedded in the The surface of the step, the several elastic members 35 are arranged on the same side of the pressure ring 34, the adjustment ring 32 and the pressure ring 34 are stacked in sequence from top to bottom on the connecting head 30, the elastic member 35 is connected to the limiting bead 36, the adjusting rod 31 is horizontally connected to the adjusting ring 32 and extends out of the adjusting port 11, and the operating member 33 is connected to the adjusting rod 31 outside the housing 10; when the adjusting rod 31 moves along the adjusting port 11, the adjusting ring 32 moves synchronously; the connecting head 30 is sleeved on the gear sleeve 20, and the limiting bead 36 is in contact with the upper surface of the gear sleeve 20; the first drive motor 40 is arranged in the housing 10 and is transmission-connected to the planetary gear set 21; the second drive motor 41 is transmission-connected to the adjusting ring 32 to drive the adjusting ring 32 to move back and forth up and down. This torque transmission assembly and mechanical torque adjustment assembly effectively form a torque clutch, preventing damage caused by insufficient torque. Specifically, during normal operation, the preset pressure of the elastic member 35 confines the limiting bead 36 between adjacent limiting portions 201 at the top of the gear sleeve 20. At this point, the output torque of the first drive motor 40 is smoothly and slip-freely transmitted to the output shaft (i.e., the screwdriver head) through the planetary gear set 21, gear sleeve 20, and limiting bead 36 / connector 30 structure. When the torque is insufficient, that is, when the resistance torque encountered by the output shaft exceeds the currently set threshold, the output shaft tends to become stuck. Under the reaction force, the planetary gear set 21 drives the gear sleeve 20 in the opposite direction. At this point, the limiting portion 201 at the top of the gear sleeve 20 overcomes the elastic pressure exerted on the limiting bead 36, pushing the limiting bead 36 away, causing it to "slip" and emit a clicking sound, thereby limiting the maximum torque transmitted to the output shaft and preventing over-torque.

[0040] The housing in this embodiment is a split structure, and the separated parts are connected by screws.

[0041] like Figure 2As shown, when torque is insufficient, a mechanical torque adjustment assembly is used to increase torque. In manual mode, the user uses the operating member 33 to move the adjustment rod 31 up and down along the adjustment port 11, changing the position of the adjustment ring 32 and the pressure ring 34. This compresses or releases the elastic member 35, changing its pressure on the stop bead 36. The greater the pressure, the higher the torque threshold required for slippage. In automatic mode, the control chip outputs instructions according to the control method to drive the second drive motor 41. The driving gear and driven rack 42 mechanism drives the operating member 33 and the adjustment rod 31 to achieve automatic and precise adjustment of the torque threshold.

[0042] Compared with traditional mechanical torque adjustment electric screwdrivers that use a rotating ring to adjust the torque in multiple gears, this application can achieve linear torque growth by moving the adjustment ring 32 up and down, making the torque output more accurate and stable, and can adapt to various work scenarios.

[0043] Among them, those skilled in the art can understand that sensors are provided on the electric screwdriver to obtain the state reference values ​​required in the control method, such as providing a speed sensor and an angular displacement sensor on the output shaft, and providing a current sensor on the first drive motor 40, etc. Those skilled in the art can select the sensor type according to actual needs.

[0044] The limiting portions 201 are evenly distributed along the circumference of the gear sleeve 20. The outer wall of the limiting portion 201 can be divided into a driving side and an escape side. The driving side, which faces the rotational drive direction of the gear sleeve 20, is a nearly vertical wall surface that is responsible for retaining the limiting bead 36 during normal operation. The escape side, located on the side facing away from the driving direction, is a gently inclined slope that allows the limiting bead 36 to pass relatively easily when excessive torque is applied. A recessed slot is formed between two adjacent limiting portions 201. The bottom of the slot can be arc-shaped or V-shaped, matching the spherical surface of the limiting bead 36 and providing a stable support point.

[0045] In some embodiments, the transmission connection between the second drive motor 41 and the adjustment ring 32 includes a driven rack 42 and a driving gear, the driven rack 42 is fixed to the outside of the operating member 33, the driving gear is transmission-connected to the second drive motor 41, and the driving gear is meshed with the driven rack 42; the second drive motor 41 drives the driving gear to rotate, thereby driving the driven rack 42 to move up or down, and the operating member 33 drives the adjustment ring 32 to move back and forth up and down, thereby realizing automatic adjustment of the torque threshold.

[0046] The second drive motor 41 may be fixed in the outermost housing of the electric screwdriver, and those skilled in the art may fix the second drive motor 41 according to actual needs.

[0047] Among them, in order to keep the height of the adjustment ring 32 fixed after the position is changed, the adjustment ring 32 can be clamped by the transmission structure between the second drive motor 41 and the adjustment ring 32, or corresponding threads can be set on the inner side of the adjustment ring 32 and the outer side of the connecting head 30 so that the adjustment ring 32 rotates and is supported by the threads to maintain the height.

[0048] In some embodiments, the adjustment opening 11 is further provided with a plurality of transverse slots in the middle thereof. Specifically, the adjustment opening 11 is generally in the shape of a letter "N". The adjustment rod 31 can move vertically along the adjustment opening 11 and drive the adjustment ring 32. At the same time, the user can rotate the adjustment rod 31 so that the adjustment rod 31 enters the transverse slots, thereby maintaining the adjustment ring 32 at different heights, changing the pressure exerted by the elastic member 35 on the stop bead 36, and thus changing the torque threshold.

[0049] In some embodiments, the adjustment ring 32 is provided with a circumferentially extending limiting groove 321, and the adjustment rod 31 is disposed in the limiting groove 321. There are two adjustment rods 31, and the limiting groove 321 contracts toward the interior of the adjustment ring 32 to form a continuous groove. By disposing two adjustment rods 31 in the limiting groove 321, the adjustment ring 32 can move smoothly up and down, and the horizontal position of the limiting rod and the rotation angle of the adjustment ring 32 can be independent of each other without interfering with each other.

[0050] In some embodiments, the operating member 33 is configured as a manual operating ring that is sleeved onto the outside of the housing 10. The adjustment rods 31 are connected to the inner sidewall of the manual operating ring. The four ends of the two adjustment rods 31 are connected to the same level of the manual adjustment ring 32. The torque threshold is changed by moving the manual adjustment ring 32 up and down.

[0051] The following describes in detail the technical solution of the present application and how the technical solution of the present application solves the above-mentioned technical problems with specific embodiments.

[0052] The following specific embodiments can be combined with each other, and the same or similar concepts or processes in certain embodiments will not be described in detail. The following describes the embodiments of the present application.

[0053] like Figure 4 As shown, the present application also discloses a control method for an electric screwdriver, which is applied to the torque-adjustable electric screwdriver as described above. The control method comprises the following steps:

[0054] 101. In response to a motor start instruction, obtain in real time a state reference value for determining a torque state of an output shaft, the state reference value including rotation speed and angular displacement data;

[0055] The motor start command refers to the start signal of the first drive motor. In response to the motor start command, the control method begins executing the following steps only after the electric screwdriver is started. The rotational speed and angular displacement data in the state reference value refer to data transmitted through the torque transmission assembly and ultimately to the output shaft. The output shaft contacts the screw and can directly reflect the current operating status. It is understood that the state reference value may also include the current value of the first drive motor.

[0056] 102. Obtain a comparison result between the state reference value and the theoretical value, and determine whether the comparison result is greater than a preset stall threshold. If so, output a start torque adjustment instruction;

[0057] The start-up torque adjustment command is a command for controlling the operation of the second drive motor. Specifically, the start-up torque adjustment command may include a step-by-step torque adjustment mode and / or a linear torque adjustment mode. The step-by-step torque adjustment mode is configured to output a motor start signal of uniform duration at preset time intervals, while the linear torque adjustment mode is configured to continuously output the motor start signal. The motor start signal has a fixed speed.

[0058] Specifically, in step-by-step torque adjustment mode, each time insufficient torque is detected, the second drive motor is controlled to rotate a fixed step length. After the movement, it pauses briefly to determine whether the screw has started to rotate. If it still has not rotated, it moves to the next step length. This cycle continues until the screw rotates or the maximum torque value setting is reached. In linear torque adjustment mode, once insufficient torque is detected, the second drive motor is controlled to run continuously at a constant, slower speed, causing the adjustment ring to continuously move downward, continuously increasing torque while continuously monitoring the output shaft speed and current. Once the speed recovery is detected, the torque increase action is immediately stopped and the current torque setting is maintained to continue operation. If the maximum position is reached and there is still no rotation, the machine will stop.

[0059] In some embodiments, a corresponding adjusted speed is queried in a speed reference table according to the current torque value, and the stall threshold is updated using the adjusted speed.

[0060] 103. Determine whether the difference between the state reference value and the theoretical value is less than a preset normal threshold value. If so, output a stop torque adjustment instruction.

[0061] When the difference between the state reference value and the theoretical value is less than a preset normal threshold, it means that the current torque of the electric screwdriver is just the torque required for the target screw working state, which effectively solves the pain point that traditional tools are difficult to accurately match the torque under unknown resistance or complex working conditions, and greatly reduces the risk of screw slippage, material damage or loose connection.

[0062] The stop torque adjustment instruction is an instruction for controlling the second drive motor to stop output.

[0063] In some embodiments, if the difference between the state reference value and the theoretical value is greater than a preset normal threshold, it is determined whether the current torque value meets the maximum value, and if so, a motor stop command is output.

[0064] In some embodiments, a time value during which the comparison result is greater than a preset stop threshold is obtained, and it is determined whether the time value is greater than a preset confirmation time value. If so, a start adjustment instruction is output.

[0065] In order to facilitate understanding of the control method of the electric screwdriver proposed in the application, the following example of a test case of the control method is given:

[0066] Normal screw-in test: Verify that the automatic torque increase is not triggered when there is no resistance or the resistance is constantly increasing.

[0067] Step resistance test: Different resistance points are set along the screw insertion path to verify that insufficient torque can be reliably detected and successfully increased at each resistance point.

[0068] Maximum torque test: Set a resistance that exceeds the maximum torque value to verify whether it can stop correctly and alarm.

[0069] False trigger test: simulates starting current surge, slight jamming and other scenarios to verify that torque increase is not falsely triggered.

[0070] Response speed test: Measures the delay from detecting insufficient torque to starting to increase torque, as well as the time required to complete a torque increase step.

[0071] Manual / automatic switching test: Verify whether the manual torque adjustment function is normal and without conflict during or after the automatic torque increase process.

[0072] Different materials / screw testing: Extensive testing is performed on different materials such as wood, metal, and plastic using screws of varying specifications.

[0073] The unique advantages of this application are that, firstly, by providing a planetary gear set on the torque transmission assembly, the output of the first drive motor is transmitted to the other end of the planetary gear set more smoothly and with greater torque. Secondly, a mechanical torque adjustment assembly is provided on the torque transmission assembly. By manually operating the adjustment lever or using the second drive motor to move the adjustment ring along the length of the electric screwdriver, pressure is applied to the pressure ring. The elastic member provided on the pressure ring is compressed or released, thereby applying different forces to the limit bead embedded in the connector. During normal operation, the pressure of the elastic member causes the limit bead to be confined between the limit portions at the top of the gear sleeve, and the output of the first drive motor is completely transmitted through the planetary gear set. When the torque is insufficient, the output shaft is stuck, the planetary gear set reversely drives the gear sleeve, and the limit portion at the top of the gear sleeve breaks through the limit bead and slips.

[0074] In addition, the present application also proposes a control method for an electric screwdriver, which comprehensively judges the output shaft state by real-time monitoring of the rotational speed and angular displacement data of the output shaft at startup, making the judgment more accurate; then, by obtaining the comparison result of the state reference value and the theoretical value, and judging whether the comparison result is greater than a preset stop threshold, the comparison result of the state reference value and the theoretical value is indirectly used to judge whether the output shaft torque is insufficient, which can avoid the influence of the state reference value fluctuation on the judgment and further improve the accuracy. When it is determined that the torque is insufficient, a start torque adjustment command is output, and the tool enters the torque increase state until it is indirectly judged that the output shaft has resumed normal operation through the difference between the state reference value and the theoretical value. It is then judged that the torque has met the requirements and a stop torque adjustment command is output. The present application combines traditional electric tools with modern sensing and control technology, which can significantly improve user experience and work efficiency. In particular, when precise torque control is required or when facing unknown resistance conditions, accurate torque matching can be achieved to avoid damage to screws or materials.

[0075] It should be understood that the application of this application is not limited to the above examples. For ordinary technicians in this field, they can make improvements or changes based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to this application.

Claims

1. A torque-adjustable electric screwdriver, characterized in that: include: A housing, wherein an outer surface of the housing is provided with an adjustment port extending along the length direction; A torque transmission assembly, comprising a gear sleeve and a planetary gear set, wherein the upper surface of the gear sleeve is provided with a plurality of raised limiting portions, the gear sleeve is rotatably disposed in the housing, and the planetary gear set is rotatably disposed inside the gear sleeve and meshes with the gear sleeve; A mechanical twist adjustment assembly, comprising a connecting head, an adjusting rod, an adjusting ring, an operating member, a pressure ring, several elastic members and corresponding limiting beads, a step being formed in the middle of the connecting head, the limiting beads being rotatably embedded in the surface of the step, the several elastic members being arranged on the same side of the pressure ring, the adjusting ring and the pressure ring being stacked in sequence from top to bottom on the connecting head, the elastic member being connected to the limiting beads, the adjusting rod being horizontally connected to the adjusting ring and extending out of the adjusting port, the operating member being connected to the adjusting rod on the outside of the housing; when the adjusting rod moves along the adjusting port, the adjusting ring moves synchronously; the connecting head being sleeved on the gear sleeve, the limiting beads being in contact with the upper surface of the gear sleeve; a first drive motor, the first drive motor being disposed in the housing and drivingly connected to the planetary gear set; A second driving motor is connected to the adjusting ring in a transmission manner to drive the adjusting ring to move up and down.

2. The torque-adjustable electric screwdriver according to claim 1, characterized in that: It also includes a driven rack and a driving gear, wherein the driven rack is fixed on the outside of the operating member, the driving gear is transmission-connected to the second drive motor, and the driving gear is meshed with the driven rack.

3. The torque-adjustable electric screwdriver according to claim 1, characterized in that: A plurality of transverse slots are also provided in the middle of the adjustment port.

4. The torque-adjustable electric screwdriver according to claim 1, characterized in that: The adjusting ring is provided with a limiting groove extending along the circumferential direction, and the adjusting rod is arranged in the limiting groove.

5. The torque-adjustable electric screwdriver according to claim 1, characterized in that: The operating member is configured as a manual operating ring, the manual operating ring is sleeved on the outer side of the shell, and the adjusting rod is connected to the inner side wall of the manual operating ring.

6. A method for controlling an electric screwdriver, characterized in that: Applied to the torque-adjustable electric screwdriver according to any one of claims 1 to 5, the control method comprises the following steps: In response to a motor start instruction, a state reference value for determining a torque state of an output shaft is acquired in real time, the state reference value including rotation speed and angular displacement data; Obtaining a comparison result between the state reference value and the theoretical value, and determining whether the comparison result is greater than a preset stall threshold, and if so, outputting a start torque adjustment instruction; It is determined whether the difference between the state reference value and the theoretical value is less than a preset normal threshold value, and if so, a stop torque adjustment instruction is output.

7. The control method of the electric screwdriver according to claim 6, characterized in that: After obtaining the comparison result between the state reference value and the theoretical value and determining whether the comparison result is greater than a preset stall threshold, and outputting a start torque adjustment instruction if so, the following steps are also included: The corresponding adjusted speed is searched in the speed reference table according to the current torque value, and the stall threshold is updated according to the adjusted speed.

8. The control method of the electric screwdriver according to claim 6, characterized in that: The step of determining whether the difference between the state reference value and the theoretical value is less than a preset normal threshold value further includes the following steps: If the difference between the state reference value and the theoretical value is greater than a preset normal threshold, it is determined whether the current torque value meets the maximum value, and if so, a motor stop command is output.

9. The control method of the electric screwdriver according to claim 6, characterized in that: The step of obtaining a comparison result between the state reference value and the theoretical value, and determining whether the comparison result is greater than a preset stall threshold, and outputting a start torque adjustment instruction if so, includes the following steps: Obtain a time value when the comparison result is greater than a preset stop threshold value, determine whether the time value is greater than a preset confirmation time value, and if so, output a start adjustment instruction.

10. The control method of the electric screwdriver according to claim 6, characterized in that: The starting twist adjustment instruction includes a step-by-step twist adjustment mode and / or a linear twist adjustment mode; the step-by-step twist adjustment mode is configured to output a motor starting signal of the same duration according to a preset time interval, and the linear twist adjustment mode is configured to continuously output a motor starting signal; wherein the speed of the motor starting signal is a fixed value.

Images