Electric pipe shearing machine and control method thereof

Abstract

The present invention discloses an electric pipe shear and a control method thereof, comprising: a main switch, which outputs a main switch status signal through its state, controls the motor to achieve forward rotation, and drives the cutting unit to achieve a first movement: the cutting unit moves from the second position to the first position; a switching switch, which outputs a switching switch status signal through its state, controls the motor to achieve reverse rotation, and drives the cutting unit to achieve a second movement: the cutting unit moves from the first position to the second position; a detection element, which detects the position of the cutting unit and outputs a detection signal to a controller; a controller, which judges or calculates an input signal and thereby controls the rotation state of the motor; the input signal includes at least a main switch status signal, a switching switch status signal, and a detection signal. The electric tool of the present invention controls the cutting unit to achieve rapid blade return after cutting, with high cutting efficiency and convenient operation.

Description

Technical Field

[0001] The present invention relates to an electric tool and a control method thereof, and in particular to an electric pipe shear and a control method thereof. Background Art

[0002] Pipes, including electrical conduits and water pipes, are commonly found in homes and construction environments. To meet the piping needs of the on-site environment, pipes are cut according to user requirements. Existing pipe cutting devices are mostly manual, which is inefficient for cutting hard pipes. The few electric pipe cutters, due to their inefficient transmission structures and control processes, suffer from low cutting efficiency, excessive size, portability issues, and complex operation. Summary of the Invention

[0003] In order to solve the deficiencies of the prior art, the object of the present invention is to provide an electric pipe shearing machine and a control method thereof which have high cutting efficiency, are easy to operate and have strong applicability.

[0004] In order to achieve the above objectives, the present invention adopts the following technical solutions:

[0005] An electric pipe shear comprises: a motor; a housing including a support portion; a cutting unit for cutting a target object, which, under the action of the motor, moves between a first position and a second position relative to the support portion of the housing; a main switch, which outputs a main switch state signal through its state, controls the motor to realize forward rotation, and drives the cutting unit to realize a first movement: the cutting unit moves from the second position to the first position; a switching switch, which outputs a switching switch state signal through its state, and controls the motor to realize reverse rotation, and drives the cutting unit to realize a second movement: the cutting unit moves from the first position to the second position; a detection element, which detects the position of the cutting unit and outputs a detection signal to a controller; a controller, which judges or calculates the input signal, and thereby controls the rotation state of the motor; the input signal at least includes a main switch state signal, a switching switch state signal and a detection signal.

[0006] In some embodiments, different combinations of input signals correspond to different special working conditions of the electric pipe shearing machine.

[0007] In some embodiments, the special operating condition includes at least a shutdown condition, a braking condition, or a speed regulation condition.

[0008] In some embodiments, the shutdown condition includes at least: a. the main switch is disconnected and the switching switch is disconnected; b. the main switch is closed and the switching switch is closed; c. the detection element detects that the blade moves to the shutdown position.

[0009] In some embodiments, the braking condition at least includes: the detection element detecting that the blade moves to the braking position.

[0010] In some embodiments, when the electric pipe shearing machine is in a shutdown condition, the cutting unit performs a deceleration motion driven by the inertia of the motor, and when the electric pipe shearing machine is in a braking condition, the cutting unit stops moving; the braking condition is automatically executed after the shutdown condition.

[0011] In some embodiments, after the motor stops moving forward / reverse, if the main switch / switch is closed again, the controller does not output a signal to other components. Only when the controller detects that the switch / main switch is closed again, the controller outputs a signal to other components.

[0012] In some embodiments, after the motor stops forward / reverse movement, if the main switch / switching switch is closed again, the controller controls the motor to start and stop immediately after t seconds. Only when the controller detects that the switching switch / main switch is closed again, the controller outputs a signal to the motor.

[0013] In some embodiments, when the electric pipe shear is in a speed regulation mode: the main switch has a seventh position and an eighth position, the main switch is in an open state when in the eighth position, and is in a fully closed state when in the seventh position. At this time, the motor outputs a maximum speed. When the main switch is between the seventh and eighth positions, the motor output speed changes according to the position of the main switch.

[0014] In some embodiments, the electric pipe shear includes a speed control switch, wherein the speed control switch has at least a seventh position and an eighth position, and the seventh position and the eighth position correspond to different rotational speeds of the motor, respectively.

[0015] In some embodiments, the speed at which the cutting unit achieves the second movement is greater than the speed at which the cutting unit achieves the first movement.

[0016] In some embodiments, the device further includes a hardware and computing unit electrically connected to the switching switch; when the electric pipe shearing machine is in a non-special working condition and the switching unit is closed, the hardware and computing unit outputs a signal to control the motor to reverse.

[0017] A control method for an electric pipe shear is applicable to the electric pipe shear, wherein a main switch or a switching switch includes at least two states: closed and open. When the main switch is closed and the switching switch is open, the motor rotates forward, driving the cutting unit to perform a first movement: the cutting unit moves from a second position to a first position. When the main switch is open and the switching switch is closed, the controller makes a judgment based on an input signal and outputs a signal. The output signal is ANDed with the switching switch state signal, and a drive signal is output to control the motor to rotate reversely, driving the cutting unit to perform a second movement: the cutting unit moves from the first position to the second position.

[0018] The benefits of the present invention are as follows: the electric tool control cutting unit of the present invention realizes rapid knife return after cutting, has high cutting efficiency and is easy to operate; the control method of the present invention ensures the stable operation of the electric pipe shear during cutting, has multiple protective shutdown measures, and is highly safe. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural diagram of embodiment 1 of the present invention;

[0020] Figure 2 is a top view of the first embodiment of the present invention;

[0021] Figure 3 is a cross-sectional view taken along plane AA when the brake assembly according to the first embodiment of the present invention is located at the fifth position;

[0022] Figure 4 is a cross-sectional view taken along plane AA when the brake assembly according to the first embodiment of the present invention is located at the sixth position;

[0023] Figure 5 yes Figure 2 Cross-section of the mid-BB plane;

[0024] Figure 6 yes Figure 2 Cross-section of the mid-CC plane;

[0025] Figure 7 This is an exploded view of the internal structure of the first embodiment of the present invention from a first perspective;

[0026] Figure 8 This is an exploded view of the internal structure of the first embodiment of the present invention from a second perspective;

[0027] Figure 9 is an exploded view of embodiment 1 of the present invention;

[0028] Figure 10 This is a structural diagram of embodiment 2 of the present invention;

[0029] Figure 11 This is a schematic diagram of the partial structure of the second embodiment of the present invention;

[0030] Figure 12 is a schematic diagram of a control circuit according to a third embodiment of the present invention;

[0031] Figure 13 Schematic diagram of the controller principle of the third embodiment of the present invention;

[0032] Figure 14 2 is a schematic diagram of a control circuit according to a fourth embodiment of the present invention. DETAILED DESCRIPTION

[0033] The embodiments of the present invention are further described below with reference to the accompanying drawings.

[0034] Example 1

[0035] like Figure 1 As shown, this embodiment relates to a power tool 10, specifically a pipe cutter for cutting various pipes, comprising a housing 11 and a battery pack 14. The housing 11 includes a tool portion 12 and a handle portion 13, with the battery pack 14 connected to the handle portion 13. Specifically, the battery pack 14 and handle portion 13 are detachably connected. In other embodiments, the pipe cutter may also be AC-powered, which is not a limitation here. A transmission device 30 and a drive device 40 are housed within the housing 11, and several switches or switch assemblies are provided on the housing.

[0036] The tool portion 12 also includes a support portion 121, to which the cutting unit 20 is connected. The tool portion 12 forms a cavity, within which a portion of the transmission device 30 is located. The cavity includes a first cavity 124 and a second cavity 123. The first end of the cutting unit 20 extends into the tool portion 12 and is located in the first cavity. The first end of the cutting unit 20 is connected to the transmission device. The second end of the cutting unit 20 and the majority of the cutting unit 20 extend out of the tool portion 12 and are positioned opposite the support portion 121. The support portion 121 includes a positioning portion 122, which is at least one curved surface or groove. The positioning portion 122 is positioned opposite the cutting unit 20, such that the support portion 121 is positioned on one side of the pipe to be cut, while the cutting unit 20 is positioned on the other side of the pipe to be cut. The positioning portion 122 is positioned against the outer wall of the pipe. The support portion 121 also includes a first groove 122a for accommodating the cutting unit 20 after the cutting motion. Specifically, the opening of the first groove 122a is provided at the positioning portion 122 and is disposed toward the cutting unit 20 . The width of the first groove is slightly greater than the width of the cutting unit.

[0037] The cutting unit 20 is connected to the driving device 40 through the transmission device 30, and under the action of the driving device 40, moves between the first position and the second position relative to the support portion 121 to achieve the first movement and the second movement. The first movement is the movement of the cutting unit 20 from the second position to the first position, which in this embodiment completes the downward shearing action. The second movement is the movement of the cutting unit 20 from the first position to the second position, which in this embodiment completes the upward recovery action. Specifically, the first position is Figure 1In the illustrated position of the cutting unit 20, the distance between the edge of the cutting unit 20 and the positioning portion 122 should be greater than the diameter of the pipe to be cut. The second position occurs when the cutting unit 20 is positioned in the middle or at the bottom of the first groove 122a. Furthermore, the distance between the first and second positions should be greater than or equal to the diameter of the pipe to be cut, and at least greater than or equal to two-thirds of the pipe diameter, to ensure complete pipe shearing or that the user can easily break off the cut pipe section after cutting.

[0038] like Figure 3-8 As shown, the transmission device 30 includes an output shaft 31, a drive shaft, an output gear assembly 33, a planetary gear assembly 34, and a brake assembly 32. The output shaft 31 passes through the first cavity 124 and the second cavity 123 and is arranged along the second axis 102. The output gear assembly 33 and the brake assembly 32 are both directly or indirectly connected to the output shaft 31.

[0039] The output wheel assembly 33 includes an output inner gear ring 331 and an output gear 332 provided on the output shaft 31. One end of the output gear 332 is connected to the output inner gear ring 331, and the other end is provided with a brake assembly 32. Specifically, the output inner gear ring 331 in this embodiment is fan-shaped, including an output hole 331a and a gear ring portion 331b. The gear ring portion 331b has a section of circular arc teeth, and the gear ring portion 331b is meshed with the output gear 332. Furthermore, the output gear 332 is a stepped two-stage gear, that is, it includes a gear portion 332a and a transmission portion 332b. The gear portion 332a is meshed with the gear ring portion 331b. Furthermore, the diameter of the gear portion 332a is smaller than the diameter of the transmission portion 332b, so that the lower edge of the output inner gear ring 331 abuts against the surface of the transmission portion 332b.

[0040] The cutting unit 20 is connected to the output hole 331a via a connecting assembly 35. The connecting assembly 35 includes a first fixing pin 351, a second fixing pin 352, and a third fixing pin 353. After being connected, the first and second fixing pins 351 and 352 are inserted into the connection hole 21 at one end of the cutting element 20. The lower ends of the first and second fixing pins 351 and 352 pass through the connection hole 21 and connect to the third fixing pin 353. The lower end of the third fixing pin 353 is connected to the output hole 331a. Specifically, the second fixing pin 352 has a circular hole at its center. The lower end of the first fixing pin 351 is cylindrical, and the corresponding connection hole 21 also has a circular portion at its center. The cylindrical lower end of the first fixing pin 351 passes through the second fixing pin 352 and the connection hole 21, respectively. Below the second fixing pin 352 are two latches, positioned relative to the lower end of the first fixing pin 351. These latches have a fan-shaped or triangular cross-section, corresponding to the connection hole 21, which also has two correspondingly shaped holes. The lower end of the second fixing pin 352 is inserted into the connection hole 21. Based on the above, the cross-sectional shape of the connecting hole 21 is consistent with the combination of the cross-sectional shapes of the lower ends of the first fixing pin 351 and the second fixing pin 352. The upper end of the third fixing pin 353 has a connecting groove 353a that is consistent with the shape of the above-mentioned connecting hole 21, and the connecting groove 353a is used to install the ends of the first fixing pin 351 and the second fixing pin 352. The lower end of the third fixing pin 353 has a flat portion 353b, and the flat portion 353b is connected to the output hole 331a, and the corresponding output hole 331a is also a flat hole. The special shapes of the above-mentioned output hole 331a and the connecting hole 21 can improve the stability of the connection and prevent relative rotation between the cutting unit 30 and the output inner gear ring. In other embodiments, one or two fixing pins can be provided, or the connecting hole 21 and the output hole 331a can be other shapes that can achieve anti-rotation, which are not limited here.

[0041] The output gear assembly 33 is connected to the planetary gear assembly 34, which is connected to the output shaft 31. Specifically, the planetary gear assembly 34 includes a plurality of planetary gears 341 and a plurality of rotating shafts 342 disposed at the center of the planetary gears. The center of the planetary gears 341 is meshed with a first sun gear 343. The lower end of the rotating shaft 342 is connected to the planetary gears 341, and the upper end of the rotating shaft 342 is fixed to the transmission part 332b, as shown in FIG. Figure 6 As shown, the output gear 332 rotates along with the planetary gear 341 in a certain state. In this embodiment, to achieve the above transmission, four planetary gears and four rotating shafts are provided. In other embodiments, other numbers can be provided, or other gear systems besides planetary gears can be used instead, which is not limited here.

[0042] Furthermore, a first sun gear 343 is mounted on the output shaft 31 and rotates driven by the output shaft 31. A second sun gear 344 is disposed below the first sun gear 343. The diameter of the second sun gear 344 is larger than that of the first sun gear 343 and larger than the outer diameters of all the planetary gears. Under certain conditions, the second sun gear 344 is in transmission connection with the brake assembly 32. Specifically, when the brake assembly 32 is in the sixth position, the second sun gear 344 meshes with the brake inner gear ring 321. The first and second sun gears 343, 344 are fixedly connected or integrally formed. The upper surface of the second sun gear 344 is curved, or the upper end of its gear portion is tilted at a certain angle to ensure that the teeth of the brake inner gear ring 321 more easily engage with the teeth of the second sun gear 344 when the brake assembly moves up and down.

[0043] The brake assembly 32 includes a retaining ring and a brake inner gear 321. The retaining ring is connected to the brake inner gear 321, and the brake assembly 32 partially moves between a fifth position and a sixth position. Specifically, in this embodiment, the retaining ring includes a first retaining ring 322 and a second retaining ring 323. The second retaining ring 323 is sleeved on the first retaining ring 322 and the brake inner gear 321. The first retaining ring 322 and the brake inner gear 321 are arranged side by side, with the first retaining ring 322 positioned above the brake inner gear 321. The first retaining ring 322 is fixed to other structures of the transmission device 30 or the housing 11, acting as a limiter. Furthermore, the second retaining ring 323 is connected to the brake inner gear 321 via a plurality of fixing members 324. The fixing members 324 penetrate through and bolt to the second retaining ring 323 and the brake inner gear 321, so that movement of the second retaining ring 323 drives movement of the brake inner gear 321. Furthermore, the inner side of the brake inner gear ring 321 is fully toothed from top to bottom, and the outer side is stepped. The lower step has a larger diameter and is provided with a groove for connecting to a fixing member 324. The upper step is connected to the inner side of the first fixing ring 322, which is located between the upper step and the second fixing ring 323, forming a tight connection between the three. In this embodiment, the brake assembly 32 moves under the control of the switch 50. In other embodiments, the movement of the brake assembly 32 can be controlled directly by the controller 70 without the switch 50.

[0044] The fixing ring is connected to the toggle switch 50 via a connecting rod 501. The toggle switch 50 is located on the handle portion 13. In this embodiment, the toggle switch 50 has a first end and a second end. The toggle switch 50 extends from the left and right sides of the handle portion 13 in the left-right direction, so that the first and second ends extend from the left and right sides of the handle portion 13, respectively. The toggle switch 50 can move in the left-right direction, having a third position and a fourth position, and can move between the third and fourth positions. Specifically, one end of the connecting rod 501 is fixedly connected to the second fixing ring 323, and the other end is connected to the toggle switch 50. Alternatively, the connecting rod 50 can be integrally formed with the toggle switch 50.

[0045] The transmission device 30 further includes a support washer 36, which is used to support and define the position of a portion of the transmission device. Specifically, the support washer 36 is used to support the brake assembly 32. Figure 3 、 4 As shown, specifically, in this embodiment, the outer edge of the support washer 36 is clamped on the corresponding groove on the inner wall of the tool portion 12, so that it supports the upper mechanism, including the brake assembly and the output wheel assembly. Further, the support washer 36 is provided in the middle of the first cavity 124.

[0046] The transmission device 30 also includes a transmission gear 37 disposed in the lower portion of the first cavity 124. The transmission gear 37 is connected to the drive device 40 via a drive shaft 41. One end of the drive shaft 41 is disposed in the tool portion 12 and connected to the transmission gear 37. The other end and a substantial portion of the drive shaft 41 are disposed within the handle portion 13. The drive shaft 41 is generally disposed along the first axis 101. The transmission gear 37 is disposed on and fixedly connected to the output shaft 31. The transmission gear 37 has a conical tooth surface that meshes with a tapered portion at one end of the drive shaft 41.

[0047] The drive mechanism 40 also includes a gearbox 42 and a motor 43. The motor is used to generate rotational motion, while the gearbox 42 is used to reduce this motion. The motor 43 is located at the rear end of the handle 13, and the gearbox 42 is connected to the motor 43 and located in front of the motor 43. The gearbox 42 is connected to the end of the drive shaft 41 away from the transmission gear 37 to provide a certain degree of reduction in speed. Due to the inconsistent transmission direction, the end of the drive shaft 41 is equipped with a bevel gear, and the corresponding transmission gear 37 has a conical tooth surface on its upper portion.

[0048] The handle 13 is equipped with a main switch 51 and a toggle switch 50. The main switch 51 is used to control the start and stop of the motor 43. The toggle switch 50 controls the movement of the brake assembly 32 via a connecting rod 501. A biasing element 502 is provided within the toggle switch 50. The circumference of the biasing element 502 abuts against the inner wall of the toggle switch 50, and its ends abut against the inner wall of the housing. This provides a restoring force when the toggle switch 50 moves between the third and fourth positions, automatically returning the toggle switch 50 from the fourth position to the third position, ensuring a comfortable feel and convenient operation.

[0049] The tool portion 12 includes a first tool shell 125 and a second tool shell 126, with an intermediate tool shell 127 disposed between the first and second tool shells. In this embodiment, the first tool shell 125 and the second tool shell 126 are two halves of the shell located on the left and right sides of the internal structure, respectively. Specifically, the second tool shell 126 forms a portion of the first cavity and the second cavity, while the first tool shell 125 forms the "lid" of these cavities. The intermediate tool shell 127 is used to divide the internal structure and is disposed between the majority of the transmission device 30 and the cutting unit 20. The first tool shell 125 and the intermediate tool shell 127 are respectively provided with a first through hole 124a and an intermediate through hole 127a for passing the connecting assembly 35. The cutting unit 20 is disposed between the first tool shell 125 and the intermediate tool shell 127. A first groove 122a is formed between the first tool shell 125 and the intermediate tool shell 127.

[0050] The cutting unit 20 includes a connecting portion 22 and a blade portion 23, and the blade portion includes a first blade portion 231 and a second blade portion 232. In this embodiment, the first blade portion 231 and the connecting portion 22 are located at different heights in the left and right directions, mainly due to the connection relationship between the cutting unit 20 and the transmission device 30, or the layout within the tool portion 12. Specifically, the first blade portion 231 is located in a plane perpendicular to the left and right directions to ensure the parallelism of the cutting surface of the pipe to be processed. The second blade portion 232 is arranged at an angle relative to the first blade portion 231 and is located between the first blade portion 231 and the connecting portion 22. A protective shell is also provided on the outer periphery of the first blade portion 231 and the second blade portion 232, covering the sides of the first blade portion 231 and the second blade portion 232 away from the pipe to be processed to ensure user safety.

[0051] The handle portion 13 and the battery pack 14 are symmetrically arranged relative to the first axis 101. The battery pack 14 is arranged below the handle portion 13, and the lower end surface of the battery pack 14 and the lower end surface of the tool portion 12 are located in the same plane in the vertical direction. Alternatively, the lower end surface of the tool portion 12 is higher than the lower end surface of the battery pack 14 in the vertical direction, and in this case, the handle portion 13 includes at least a portion that is inclined relative to the front-to-back direction. That is, the orthographic projection of the battery pack 14 in a plane perpendicular to the front-to-back direction is the first projection, and the orthographic projection of the shell in a plane perpendicular to the front-to-back direction is the second projection, and at least a portion of the first projection is below the second projection. The above structural layout ensures that the center of the power tool is located in the handle, which is effortless for the user to use and easy to place.

[0052] The power tool 10 further includes a steering controller 60 for switching the drive mechanism between forward and reverse rotation based on the power tool's status or user operation, thereby achieving the first or second movement of the cutting unit 20. In this embodiment, the steering controller 60 is a sensor element that senses the position of the switch 50 and provides feedback to a circuit board 61 to control the motor's switching between forward and reverse rotation.

[0053] The power tool 10 also includes a shifting mechanism 421. After the cutting unit 20 moves to the first position or the second position, the shifting mechanism 421 causes the drive device 40 or the transmission device 30 to be in a clutched state. Alternatively, when the cutting unit 20 moves between the first position and the second position, the motor 43 is stalled or the force applied to the cutting unit 20 exceeds the maximum load of the motor due to a target object or other problem. The shifting mechanism 421 causes the drive device 40 or the transmission device 30 to be in a clutched state to protect the internal structure of the power tool 10. In this embodiment, the shifting mechanism 421 includes several elastic members and an inner gear ring with an inclined surface. The elastic members abut the inclined surface. The shifting mechanism 421 is preferably located in the gear box 42 at the front end of the motor 43. In this case, the torque is relatively small, which facilitates the structural configuration. In other embodiments, the shifting mechanism 421 may also be other structures capable of achieving a clutch function, which is not limited here.

[0054] This embodiment is further described in conjunction with the working process:

[0055] After the user aligns the power tool 10 to the working position, he presses the main switch 51 and the motor 43 starts. Driven by the motor 43, the drive shaft 41 rotates, driving the transmission gear 37 of the transmission device 30 to rotate, and then driving the output shaft 31 to rotate. At this time, the motor 43 rotates in the forward direction, and the output shaft 31 also rotates in the forward direction. The switch 50 is in the third position, and the brake assembly 32 is in the fifth position. Figure 3 As shown, the brake inner gear 321 is separated from the second sun gear 344. Driven by the output shaft 31, the first sun gear 343 transmits the rotation to the planetary gear 341, and the output gear 332 rotates under the action of the rotating shaft 342 in the center of the planetary gear 341, and rotates relative to the output shaft 31. The output gear 332 drives the output inner gear 331 to rotate, and then drives the cutting unit 20 to move from the second position to the first position, realizing the first movement and completing the cutting of the pipe to be cut. The user toggles the switch 50 to the fourth position, and the steering controller 60 outputs a signal to the circuit board 61, controlling the motor 43 to reverse, and the output shaft 31 to rotate in the opposite direction. At the same time, the brake assembly 32 is in the sixth position, as shown in FIG. Figure 4As shown, the brake inner gear 321 is engaged with the second sun gear 344, fixing the second sun gear 344 and the first sun gear 343. The output gear 332 rotates under the action of the output shaft 31, driving the output inner gear 331 to rotate. In this way, the cutting unit 20 moves from the first position to the second position, realizing the second movement, and completing the retraction of the cutting unit 20. Since the drive of the second movement does not pass through the deceleration of the planetary gear assembly 34, but directly moves according to the output wheel 31, the speed of the second movement is greater than the first movement, achieving the effect of quickly retracting the knife. In this embodiment, after experimental testing, the speed of the second movement is at least 3 times that of the first movement. The knife can be retracted by a switch, which improves the working efficiency of the tool.

[0056] Example 2

[0057] like Figure 10-11 As shown, the same or similar components as those in the first embodiment are numbered the same. For ease of description, the present embodiment only describes the differences from the first embodiment.

[0058] The housing 11 is provided with a steering switch 52 and a brake switch 53. The steering switch 52 moves between the left and right positions, controlling the motor 43 to achieve forward and reverse rotation, respectively. The brake switch 53 controls the movement of the brake assembly between the third and fourth positions, achieving separation and engagement of the brake assembly with the sun gear. In this embodiment, after completing the first shearing action, the user needs to actively adjust the steering switch 52 to reverse the motor and then adjust the brake switch 53. The advantage of this structure is high stability. In other embodiments, the brake switch 53 is electrically connected to the steering switch 52, so that after the brake switch 53 moves to the fourth position, the steering switch 52 is automatically toggled to the right position, or the steering switch 52 is controlled by the circuit board 61 to achieve the above-mentioned action, ultimately achieving reverse rotation of the motor 43.

[0059] Example 3

[0060] like Figure 12-13 As shown, the same or similar components as those in the first and second embodiments are numbered the same. For ease of description, the present embodiment only describes the differences from the first and second embodiments.

[0061] The power tool of this embodiment, particularly the electric pipe cutter, further includes a controller 70, which may include any one or a combination of a single-chip microcomputer or microcontroller (MCU), an ARM chip (a high-performance RISC (reduced instruction set computing) microprocessor, or a DSP chip (a general-purpose digital signal processor). Controller 70 is located within circuit board 61 and performs logical operations based on input signals to control the rotation of the motor.

[0062] The circuit board 61 is arranged between the battery pack 40 and the handle portion 13. Specifically, the circuit board 61 can be arranged between the motor 43 and the battery pack 40 in the handle portion 13, where a connection socket for the battery pack 40 is provided, and the circuit board 61 can be arranged in the connection socket. The power supply circuit is electrically connected to the controller 70 and is used to convert electrical energy from the power supply into electrical energy that can be used to operate the controller 70 and other circuit components. In this embodiment, the power supply is the battery pack 40, so the power supply circuit can include a DC-DC conversion chip. Those skilled in the art should understand that the power supply is not limited to the scenario of using the battery pack 40, and can also be powered by AC power or AC power, in combination with corresponding rectification, filtering and voltage regulation circuits to realize power supply to various circuit elements. In this case, the power supply circuit includes rectification, filtering and voltage regulation circuits. In this case, the circuit board 61 can be arranged in other vacant positions of the handle portion 13.

[0063] The main switch SW2 on the handle 13 is electrically connected to the controller 70. The on and off of the main switch SW2 controls the start and stop of the motor 43. When the main switch SW2 is closed, the motor 43 rotates forward, thereby driving the cutting unit 20 to achieve the first motion. In this embodiment, SW2 is a mechanical switch, preferably a high-current mechanical switch. The controller 70 detects the on / off signal of SW2, performs corresponding logical operations and judgments, and outputs signals to other components.

[0064] The housing 11 is also provided with a switch SW1, which is electrically connected to the controller 70 and outputs a switch state signal SW1_C based on the state of the switch SW1. The electric pipe shear also includes a hardware AND operation element 90, located on the circuit board 61. This hardware AND operation element 90 performs an AND operation based on the switch state signal SW1_C and other input signals to control the motor 43 to reverse and drive the cutting unit 20 to achieve the second motion. Simultaneously, the switch state signal SW1_C is transmitted to the controller 70, which performs logical analysis and operations based on the SW2 off signal and the switch state signal SW1_C, ultimately outputting signals to other components.

[0065] like Figure 12As shown, the electric pipe shearing machine of this embodiment also includes MOS transistor assemblies (Q1, Q2, Q3, and Q4), and the controller is not shown in the figure. The drive control signals output by the MOS transistor assemblies control the forward or reverse rotation of the motor 43. In other embodiments, the MOS transistor assemblies can also be selected from field-effect transistors, IGBT transistors, etc., without limitation. The controller 70 can be connected to a hardware drive circuit 80 via several drive ports. The hardware drive circuit 80 is electrically connected to the windings of the motor 43 to ensure that the signal voltage matches the applicable voltage of the MOS transistor assemblies, thereby driving the rotor of the brushed motor of this embodiment. In other embodiments, the motor can also be a brushless motor, and the circuit should be adaptively adjusted. One end of the MOS transistor assembly is electrically connected to the drive signal output terminal of the hardware drive circuit 80, and the other end of the MOS transistor assembly is electrically connected to the windings of the motor 43. Q1, Q2, Q3, and Q4 change their connection state based on the signal output by the controller 70. Specifically, when SW2 is closed, the circuit is conductive and a certain signal is output to the controller 70, turning on Q1 and Q4, driving the motor 43 to rotate in the forward direction. Conversely, when SW2 is disconnected, the circuit is disconnected and a certain signal is output to the controller 70, causing Q1 and Q4 to be turned off and the motor 43 to stop running. In other embodiments, the drive signal applied by the controller 70 to the hardware drive circuit can be a PWM control signal, which can control the motor to accelerate, decelerate, rotate counterclockwise, or rotate clockwise.

[0066] Switch SW1 has two states: closed and open. Switch SW1 outputs a switching state signal SW1_C to the hardware AND operation element 90. When SW1 is closed, it outputs a high level to the hardware AND operation element 90. When SW1 is open, it outputs a low level to the hardware AND operation element 90. The hardware AND operation element 90 performs an AND operation on the switching state signal SW1_C and the input signal. Only when the switching state signal SW1_C and the controller 70 output signal are both high levels does it output a high-level drive signal to subsequent components. Specifically, when SW1 is closed, the hardware AND operation element 90 detects that the switching state signal SW1_C is high. The hardware AND operation element 90 detects the controller 70 output signal and performs a logical operation. When the input signal and the switching state signal SW1_C are both high levels, the hardware AND operation element 90 outputs a high level to the hardware drive circuit 80. The hardware drive circuit 80 outputs a high-level drive signal to Q2 and Q3, turning on Q2 and Q3 and driving the motor 43 in reverse. Conversely, when SW1 is disconnected, the hardware AND operation element 90 detects that the switching state signal SW1_C is at a low level. The hardware AND operation element 90 outputs a low level to the hardware drive circuit 80, which in turn outputs a low-level drive signal to Q2 and Q3. Q2 and Q3 are turned off, and the motor 43 stops operating. In this embodiment, the switching switch SW1 is an electronic switch, and the input voltage value does not match the MOS transistor component. The hardware drive circuit 80 is used to increase the driving capability of the switching state signal SW1_C so that the output signal matches the MOS transistor component. In this embodiment, the use of the hardware AND operation element 90 to perform the AND operation judgment, rather than directly using the controller 70 to perform the logical operation, can ensure the circuit response speed and circuit operation stability.

[0067] like Figure 13 As shown, when the switch SW1 is closed or open, the controller 70 also receives the switching state signal SW1_B. When the main switch SW2 is closed or open, the controller 70 receives the main switch signal SW1_A. Based on the switching state signal SW1_B, the main switch signal SW1_A, and the input signal S, the controller 70 determines whether the electric pipe shear is in a normal operating state. The controller 70 outputs a high-level signal H1 to the hardware AND operation element 90. If the AND operation result is high, it is output to the hardware drive circuit 80, converted into a high-level drive signal MH1, and sent to the MOS transistor component, driving the motor 43 in reverse.

[0068] Input signal S is a signal obtained by controller 70 based on the state of cutting unit 20. Input signal S includes both high and low level signals. Specifically, the aforementioned special operating conditions include at least a shutdown condition, a braking condition, or a speed regulation condition. When at least one of the shutdown, braking, or speed regulation conditions is present, controller 70 outputs a low-level signal to hardware AND operation element 90. If the AND operation result is low, it is output to hardware drive circuit 80, which converts it into a low-level drive signal and sends it to the MOS transistor component, thereby not driving motor 43.

[0069] The shutdown condition refers to situations where the power supply to the motor 43 stops, and the motor 43 still has a certain output speed under the action of inertia. The shutdown condition is generally applicable after the electric pipe shear completes forward cutting, that is, the cutting unit 20 completes or is about to complete the first movement, and is also applicable to other situations where the user needs to stop the tool. The shutdown condition of the motor 43 is achieved by at least one of the following actions, but is not limited to these: a. The main switch SW2 is disconnected, and the switching switch SW1 is disconnected; b. The main switch SW2 is closed, and the switching switch SW1 is closed; c. The detection element detects that the blade moves to the shutdown position. The corresponding usage scenario of action a is: after the main switch SW2 of the electric pipe shear is pressed, the cutting unit 20 completes forward cutting, the user releases the main switch SW2 but does not press the switching switch SW1, and the controller 70 outputs a low level signal. Action b corresponds to the following usage scenario: when the main switch SW2 is closed and the switch SW1 is closed again, the controller 70 outputs a low-level signal, which, after an AND operation, outputs a low-level drive signal, preventing the motor 43 from reversing. Alternatively, when the switch SW1 is closed and the main switch SW1 is closed again, the controller 70 outputs a low-level signal, which, after an AND operation, outputs a low-level drive signal, preventing the motor 43 from reversing. Action c corresponds to the following usage scenario: the electric pipe shear further includes a detection element. When the electric pipe shear nearly completes forward cutting of the target object, the cutting unit 20 moves from the second position to a stop position close to the first position. Upon detecting that the cutting unit 20 has reached the stop position, the detection element generates a corresponding input signal S, which is transmitted to the controller 70, resulting in a low-level signal output. Specifically, the detection element can be a sensor, particularly a Hall effect sensor. A magnetic body is provided in the cutting unit 20. When the cutting unit 20 moves to the stop position, the Hall effect sensor senses the magnetic body and outputs a corresponding signal. In other embodiments, other types of sensors or detection elements can also be used, and this is not limiting here.

[0070] When the electric pipe shear is in a braking state, the cutting unit 20 stops moving. Specifically, the cutting unit 20 and the transmission device 30 are in a clutched state, the transmission device 30 is in a clutched state, the transmission device 30 is in a clutched state, the transmission device 40 is in a clutched state, or the drive device 40 is in a clutched state, allowing the cutting unit 20 to stop moving immediately. This clutching state is achieved by providing a shift mechanism in the electric pipe shear. Alternatively, the controller 70 outputs a signal to Q3 and Q4 based on the received signal, directly short-circuiting the MOS transistor components and further rapidly stopping the motor 43, thereby allowing the cutting unit 20 to stop moving immediately. The braking state is achieved by at least the following actions, but is not limited to these: the detection element detects that the blade has moved to the braking position. In the braking state, when the electric pipe shear completes forward cutting of the target object, the cutting unit 20 moves from the second position to the first position, which is the braking position. After the detection element detects that the cutting unit 20 has reached the braking position, it generates a corresponding input signal S and transmits it to the controller 70, outputting a low-level signal. When the electric pipe shear performs reverse cutting, the cutting unit 20 moves from the first position to the second position, which is the braking position.

[0071] In other embodiments, when the shutdown condition does not include the aforementioned condition b, the braking condition may further include the following: the main switch remains closed. After the switch SW1 is closed, the controller 70 outputs a signal to the hardware AND operation element 90, which in turn controls the motor 43 to reverse. After the main switch SW2 is opened, the cutting unit 20 brakes. At this point, the cutting unit 20 maintains the user's desired angle, facilitating control of the reverse opening angle based on the thickness of the pipe, thereby saving cutting time.

[0072] In another embodiment, the braking condition is configured to automatically execute after the stop condition. Specifically, the electric pipe shear has only one position: a stop position close to the first position, or a brake position similar to or identical to the first position. The stop position is preferred, allowing for the sliding motion of the cutting unit 20 driven by motor inertia. Based on the time and distance of the sliding motion, the braking condition can be configured to automatically execute T seconds after the stop condition is completed.

[0073] The electric pipe shear also includes a speed control switch or a main switch that is an electronic switch with speed control functionality. When the electric pipe shear is in speed control mode, the main switch SW2 has a seventh and eighth positions. When in the eighth position, the main switch SW2 is open, and when in the seventh position, the main switch SW2 is fully closed. At this point, the motor outputs maximum speed. When the main switch SW2 is between the seventh and eighth positions, the motor output speed varies according to the position of the main switch. Specifically, the position of the main switch SW2 changes the resistance of the component, thereby achieving motor speed control. Other switches based on other principles are also possible and are not limiting here. When the main switch SW2 is between the seventh and eighth positions, the input signal S to the controller 70 is low, and the controller 70 outputs a low-level signal. In other embodiments, the electric pipe shear includes a speed control switch SW3, which has at least a seventh and eighth position, corresponding to different motor speeds. The speed control switch SW3 also has a ninth position. When in the ninth position, the speed control switch is open. When the speed regulating switch SW3 is located at the seventh position or the eighth position, the input signal S of the controller 70 is at a low level, and the controller 70 outputs a low level signal.

[0074] In this embodiment, the speed at which the cutting unit 20 achieves the second movement is greater than the speed at which the cutting unit achieves the first movement, and this is primarily achieved in accordance with the principles of Embodiment 1. In this embodiment, when the cutting unit 20 completes the second movement, a stop position is provided near the second position, and a brake position is also provided at the second position, and the control method is the same as described above.

[0075] Special operating conditions also include self-stop conditions, which are similar to stop conditions. In this embodiment, after the motor 43 stops moving in the forward direction, that is, after executing the forward stop condition or braking condition, if the main switch SW2 is closed again, the controller 70 does not output a signal or outputs a low-level signal to the motor. Only when the controller detects that the switch SW1 is closed again, the controller 70 outputs a high-level signal to the motor 43. When the motor 43 stops moving in the reverse direction, that is, after executing the reverse stop condition or braking condition, if the switch SW1 is closed again, the controller 70 does not output a signal or outputs a low-level signal to the motor. Only when the controller detects that the main switch SW2 is closed again, the controller 70 outputs a high-level signal to the motor 43. The self-stop condition can prevent the cutting unit 20 that has reached the bottom position (first position or second position) from moving again, causing damage to the mechanical structure, especially the internal part of the transmission device.

[0076] In other embodiments, the automatic stop condition employs the following scheme: after the motor 43 stops moving, if the main switch or the transfer switch is closed again, the controller 70 outputs a signal to control the motor to stop immediately t seconds after starting. Only when the controller 70 detects that the transfer switch or the main switch is closed again does the controller 70 output a high-level signal to the motor 43. Specifically, if t ≤ 2s, in this embodiment, the mechanical structure of the electric pipe shear, particularly the transmission device, is allowed to withstand the effects of gear slippage caused by movement toward the bottom position for t seconds, allowing the user to hear a "clicking" sound from the electric pipe shear, alerting them that the cutting unit has reached the required stopping position, and then immediately stopping, thus protecting the mechanical structure. The detection element also operates normally in the automatic stop condition to ensure that the cutting unit has not moved to the second position, the first position, or the stop position after the motor stops moving.

[0077] Example 4

[0078] like Figure 14 As shown, components identical or similar to those in Embodiments 1, 2, and 3 are numbered the same. For ease of description, this embodiment only describes the differences from Embodiments 1, 2, and 3. In this embodiment, both the main switch J1 and the transfer switch J2 are mechanical switches. The controller 70 detects signals from both and performs AND operations within the controller 70. The control method is the same as that of Embodiment 3.

[0079] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the above embodiments do not limit the present invention in any form, and any technical solutions obtained by equivalent replacement or equivalent transformation fall within the scope of protection of the present invention.

Claims

1. An electric pipe shearing machine, characterized in that: include: Motor; a housing including a support portion; a cutting unit, for cutting a target object, and moving between a first position and a second position relative to the supporting portion of the housing under the action of the motor; The main switch outputs a main switch state signal according to its state, controls the motor to realize forward rotation, and drives the cutting unit to realize a first movement: the cutting unit moves from the second position to the first position; A switching switch outputs a switching switch state signal through its state, which is used to control the motor to achieve reverse rotation, thereby driving the cutting unit to achieve a second movement: the cutting unit moves from the first position to the second position; A detection element detects the position of the cutting unit and outputs a detection signal to the controller; The controller judges or calculates the input signal to control the rotation state of the motor; the input signal at least includes a main switch state signal, a switching switch state signal and a detection signal.

2. The electric pipe shearing machine according to claim 1, characterized in that: Different combinations of the input signals correspond to different special working conditions of the electric pipe shearing machine.

3. The electric pipe shearing machine according to claim 2, characterized in that: The special operating conditions include at least a shutdown condition, a braking condition or a speed regulation condition.

4. The electric pipe shearing machine according to claim 3, characterized in that: The shutdown operating condition at least includes: a. the main switch is disconnected and the switching switch is disconnected; b. the main switch is closed and the switching switch is closed; c. the detection element detects that the blade moves to the shutdown position.

5. The electric pipe shearing machine according to claim 3, characterized in that: The braking condition at least includes: the detection element detecting that the blade moves to the braking position.

6. The electric pipe shearing machine according to claim 3, characterized in that: When the electric pipe shear is in a shutdown state, the cutting unit performs a deceleration motion driven by the inertia of the motor. When the electric pipe shear is in a braking state, the cutting unit stops moving. The braking state is automatically executed after the shutdown state.

7. The electric pipe shearing machine according to claim 6, characterized in that: After the motor stops moving forward / reverse, if the main switch / switch is closed again, the controller does not output a signal to other components. Only when the controller detects that the switch / main switch is closed again, the controller outputs a signal to other components. Alternatively, after the motor stops moving forward / reverse, if the main switch / switching switch is closed again, the controller controls the motor to start and stop immediately after t seconds. Only when the controller detects that the switching switch / main switch is closed again, the controller outputs a signal to the motor.

8. The electric pipe shearing machine according to claim 3, characterized in that: When the electric pipe shear is in the speed regulation mode: the main switch has a seventh position and an eighth position. When the main switch is in the eighth position, it is in an open state. When the main switch is in the seventh position, it is in a fully closed state. At this time, the motor outputs the maximum speed. When the main switch is between the seventh and eighth positions, the motor output speed changes according to the position of the main switch. Alternatively, the electric pipe shear includes a speed regulating switch, and the speed regulating switch has at least a seventh position and an eighth position, and the seventh position and the eighth position correspond to different rotational speeds of the motor respectively.

9. The electric pipe shearing machine according to claim 1, characterized in that: The speed at which the cutting unit realizes the second movement is greater than the speed at which the cutting unit realizes the first movement.

10. The electric pipe shearing machine according to claim 1, characterized in that: It also includes a hardware and computing unit electrically connected to the switch; when the electric pipe shear is in a non-special working condition and the switch is closed, the hardware and computing unit outputs a signal to control the motor to reverse.

11. A control method for an electric pipe shearing machine, applicable to the electric pipe shearing machine according to claim 1, characterized in that: The main switch or transfer switch includes at least two states: closed and open; When the main switch is closed and the switching switch is opened, the motor rotates forward, driving the cutting unit to perform a first movement: the cutting unit moves from the second position to the first position; When the main switch is disconnected and the switching switch is closed, the controller makes a judgment based on the input signal and outputs a signal. The output signal is ANDed with the switching switch status signal and outputs a driving signal to control the motor to reverse and drive the cutting unit to achieve a second movement: the cutting unit moves from the first position to the second position.

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