Power tool

Abstract

The present invention discloses a power tool, comprising: a tool accessory; a motor for driving the tool accessory; a power supply module for at least supplying electrical energy to the motor; a drive circuit for loading the electrical energy of the power supply module onto the motor; a control module for controlling the drive circuit; a switch device for controlling the power tool, the switch device comprising: a trigger mechanism; a current switch for connecting and disconnecting the electrical connection between the power supply module and the motor, the current switch being associated with the trigger mechanism and triggered by the trigger mechanism; a signal switch for at least outputting an electrical signal to the control module to control the motor brake by the control module, the signal switch being associated with the trigger mechanism and triggered by the trigger mechanism. For the power tool of the present invention, the switch device integrally integrates a current switch and a signal switch, which can enhance the stability of the switch system, reduce the failure risk, and has a compact structure and low cost.

Description

Technical Field

[0001] The invention relates to an electric tool. Background Art

[0002] Electric tools such as angle grinders and circular saws have a relatively large working current, which is usually carried by a high-current switch set on the main circuit. The contacts of the high-current switch are prone to sparks, causing deformation or failure of the contacts, posing a safety hazard. Therefore, there is an urgent need for a solution that can avoid switch control failure when carrying a large current, improve the accuracy of switch control in electric tools, and further improve the safety of electric tools. Summary of the invention

[0003] In order to solve the deficiencies of the prior art, the present invention provides an electric tool with high safety, low cost and switch control that is not prone to failure.

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

[0005] An electric tool comprises: a tool accessory; a motor for driving the tool accessory; a power supply module, at least for providing electrical energy to the motor; a drive circuit, for loading the electrical energy of the power supply module to the motor; a control module, for controlling the drive circuit; a switch device, for controlling the electric tool, the switch device comprising: a trigger mechanism; a current switch, for connecting and disconnecting the electrical connection between the power supply module and the motor, the current switch being associated with the trigger mechanism so as to be triggered by the trigger mechanism; a signal switch, at least for outputting an electrical signal to the control module so that the control module controls the motor brake, the signal switch being associated with the trigger mechanism so as to be triggered by the trigger mechanism.

[0006] Optionally, it also includes: a power supply circuit, electrically connected to the power supply module and the control module, and used to convert the electric energy of the power supply module into electric energy that can power the control module; the signal switch is electrically connected to the power supply circuit, and the signal switch is also used to trigger the power supply circuit to operate so that the power supply circuit powers the control module.

[0007] Optionally, the switch device includes: a switch housing for accommodating the current switch and the signal switch; an actuating rod connected to the trigger mechanism and capable of moving in a first direction under the drive of the trigger mechanism; the current switch includes: a movable contact frame associated with the actuating rod and capable of moving in a direction opposite to the first direction under the drive of the actuating rod; a static contact arranged in the switch housing; a moving contact arranged in the movable contact frame, and the moving contact can contact or separate from the static contact by following the movement of the movable contact frame relative to the static contact.

[0008] Optionally, the static contact includes: two first static contacts electrically connected to the motor, and two second static contacts electrically connected to the power supply module; the two first static contacts are connected by a metal sheet, and the two second static contacts are connected by a metal sheet; the moving contact includes: two first moving contacts respectively used for connecting with the two first static contacts, and two second moving contacts respectively used for connecting with the two second static contacts; the two first moving contacts are connected by a metal sheet, and the two second moving contacts are connected by a metal sheet.

[0009] Optionally, the switch device includes: a first elastic element disposed between the actuating pull rod and the switch housing for resetting the actuating pull rod.

[0010] Optionally, the switch device includes: a second elastic element disposed between the actuating pull rod and the movable contact holder for enabling the actuating pull rod to drive the movable contact holder to move.

[0011] Optionally, the current switch includes: a stopper for abutting against the movable contact holder, the stopper being capable of moving in a second direction substantially perpendicular to the first direction; an elastic conductor disposed on the stopper, the elastic conductor being capable of following the movement of the stopper; a conductive sheet disposed near the stopper, the conductive sheet being in contact with the elastic conductor; the elastic conductor can move relative to the conductive sheet following the movement of the stopper.

[0012] Optionally, one end of the actuating pull rod is formed with a wedge-shaped structure for lifting the stopper.

[0013] Optionally, the elastic conductor includes: a first elastic conductor and a second elastic conductor, the first elastic conductor and the second elastic conductor being connected by a conductor; the conductive sheet includes: a first conductive sheet in contact with the first elastic conductor; a second conductive sheet in contact with the second elastic conductor; the second conductive sheet includes a first portion and a second portion which are separated from each other; when the second elastic conductor is in contact with the first portion, the signal switch is in a first state; when the second elastic conductor is in contact with the second portion, the signal switch is in a second state; when the signal switch switches from the second state to the first state, it is used to trigger the control module to control the motor brake; when the stopper moves in the second direction, the second elastic conductor first contacts the first portion and then contacts the second portion.

[0014] Optionally, the movable contact holder is provided with a groove, and when the stopper moves in the second direction to contact the groove, the second elastic conductor contacts the second part.

[0015] The electric tool of the present invention integrates a current switch and a signal switch in the switch device, which can enhance the stability of the switch system, reduce the failure risk, and has a compact structure and low cost. Description of the Drawings

[0016] Figure 1 is an external view of an electric tool in an embodiment;

[0017] Figure 2 is Figure 1 a schematic circuit diagram of an embodiment of the electric tool shown;

[0018] Figure 3 is Figure 1 a structural diagram of the handle part of the electric tool shown;

[0019] Figure 4 is Figure 1 a structural diagram of the switch device of the electric tool shown

[0020] Figure 5 is Figure 4 a partial structural diagram of the switch device shown;

[0021] Figure 6a is Figure 4 a structural diagram of the stopper part in the switch device shown;

[0022] Figure 6b is Figure 4 a structural diagram of the PCB circuit board part in the switch device shown;

[0023] Figures 7a to 7c is Figure 4 different motion states of the switch device when the electric tool starts up.

[0024] Figures 8a to 8b is Figure 4 different motion states of the switch device when the electric tool shuts down. Detailed Embodiments

[0025] The present invention will be specifically introduced below in conjunction with the drawings and specific embodiments.

[0026] The power tools of the present invention can be handheld power tools, garden tools, etc., without limitation here. The power tools of the present invention include but are not limited to the following: power tools that require speed regulation such as screwdrivers, electric drills, wrenches, angle grinders, etc., power tools that may be used to sand workpieces such as sanding machines, power tools that may be used to cut workpieces such as reciprocating saws, circular saws, jigsaws, etc.; power tools that may be used for impact such as electric hammers. These tools may also be garden tools, such as pruning machines, chain saws; in addition, these tools may also be used for other purposes, such as mixers. As long as these power tools can adopt the substantial content of the technical solutions disclosed below, they will fall within the protection scope of the present invention.

[0027] Referring to Figure 1 , as an implementation, taking the electric circular saw as an example for the power tool 10, Figure 1 The power tool shown specifically includes: a housing 11, a tool accessory, a motor 13, and a switch device 16.

[0028] The housing 11 is used to accommodate the motor 13, circuit board, etc. Optionally, the power tool 10 further includes a handle 12, the handle 12 is formed by the housing 11, and a switch device 16 is provided on the handle 12 for the user to operate. The switch device 16 is triggered by the user to control the operation process of the power tool 10. The switch device 16 includes a trigger mechanism 161, and the trigger mechanism 161 can be triggered. The tool accessory is used to realize the function of the power tool 10. For the electric circular saw, the tool accessory is specifically a saw blade (not shown). For other power tools, the tool accessory is specifically an accessory that realizes the function of the power tool. For example, for an electric drill, the tool accessory is specifically a drill bit. The motor 13 is used to drive the tool accessory to work. The motor 13 includes a stator, a rotor, windings, and a motor shaft 131, and the motor shaft 131 is driven by the rotor of the motor 13.

[0029] For the circular saw, the power tool further includes: a bottom plate 17 for contacting the workpiece, the housing 11 is mounted on the bottom plate 17; a saw blade cover 19, the saw blade cover 19 is connected to the housing 11; a saw blade shaft 18 for supporting the saw blade to rotate in the saw blade cover 19 to realize cutting operation on the workpiece; a transmission device 14 for transmitting the power output by the motor 13 to the tool accessory. Specifically, the transmission device 14 connects the motor shaft 131 and the saw blade shaft 18, and conducts the rotational motion of the motor shaft 431 to the saw blade shaft 18 to drive the saw blade to operate. The transmission device 14 may specifically include a reduction mechanism. For example, a worm and worm gear mechanism that meshes with each other. The worm and worm gear may include a gear structure with different tooth number ratios, or a synchronous belt drive structure with different synchronous pulley radii. Optionally, the motor 13.

[0030] Referring to Figure 2, To control the operation of the power tool 10, the power tool 10 further includes: a power supply module 24, a control module 21, a current switch 26, and a signal switch 27.

[0031] The power supply module 24 is used to supply electrical energy to the power tool 10. More specifically, the power supply module 24 is at least used to supply power to the motor 13. The power supply module 24 can include a DC power supply or an AC power supply. In some embodiments, the power supply module 24 includes a DC power supply. More specifically, the power supply module 24 includes a battery pack 15. In other embodiments, the power supply module 24 includes an AC power supply. The power tool 10 is powered by an AC power supply. The AC power supply can be 120V or 220V AC mains. The power supply module includes an AC-DC power conversion circuit, which is connected to the alternating current and is used to convert the alternating current into electrical energy that can be used by the power tool 10.

[0032] Optionally, the power tool further includes a drive circuit 22. The control module 21 is electrically connected to the drive circuit 22 to output a drive signal to control the operation of the drive circuit 22. In some embodiments, the control module 21 uses a dedicated control chip, such as a microcontroller (MCU, Microcontroller Unit), a DSP (Digital Signal Processor) chip, an ARM (Advanced RISC (Reduced Instruction Set Computer) Machine, RISC microprocessor) chip, etc.

[0033] The drive circuit 22 is used to load the voltage of the power supply module onto the motor 12 to drive the motor 13 to output power. It is electrically connected to the motor 13. The drive circuit 22 is also electrically connected to the control module 21 and receives a drive signal from the control module 21. The drive circuit 22 is specifically electrically connected to the three-phase electrodes U, V, and W of the motor 13, and thus is connected to the winding of the motor 13 to drive the motor 13 to operate. As Figure 2 shown, the drive circuit 22 includes drive switches VT1, VT2, VT3, VT4, VT5, and VT6. The drive switches VT1, VT2, VT3, VT4, VT5, and VT6 form a three-phase bridge. The drive switches can be MOSFETs or IGBTs. The drive switches VT1 to VT6 change their on states according to the drive signal output by the control module 21, thereby changing the voltage state of the power supply module 24 loaded on the winding of the motor 13, generating an alternating magnetic field to drive the rotor to rotate, and thus realizing the drive of the motor 13 to drive the motor 13 to operate. In this embodiment, the drive circuit 22 is electrically connected or disconnected from the power supply module 24 through the current switch 26.

[0034] Refer to Figure 2, the switch device 16 further includes: a current switch 26 for connecting and disconnecting the electrical connection between the power supply module 24 and the motor 13, and the current switch 27 is associated with the trigger mechanism 161 to be triggered by the trigger mechanism 161; a signal switch 27 for at least outputting an electrical signal to the control module 21 to enable the control module 21 to control the braking of the motor 13, and the signal switch 27 is associated with the trigger mechanism 161 to be triggered by the trigger mechanism 161.

[0035] Specifically, one end of the current switch 26 is electrically connected to the power supply module 24, and the other end is electrically connected to the drive circuit 22. The motor 13 is electrically connected or disconnected from the power supply module 24 through the drive circuit 22 and the current switch 26. The current switch 26 is triggered by the trigger mechanism 161 to switch between the on state and the off state. When the current switch 26 is in the on state, the electrical connection between the drive circuit 22 and the power supply module 24 is connected, and the power supply module 24 can supply power to the motor 13 through the drive circuit 22. Specifically, when the current switch 26 is in the on state, the electrical connection between the drive circuit 22 and the power supply module 24 is connected, and the control module 21 controls the electrical energy loaded from the power supply module 24 to the motor 13 by controlling the conduction or cutoff of the drive switch of the drive circuit 22; when the current switch 26 is in the off state, the electrical connection between the drive circuit 22 and the power supply module 24 is disconnected, and the power supply module 24 stops supplying electrical energy to the drive circuit 22.

[0036] The signal switch 27 is associated with the trigger mechanism 161 to be triggered by the trigger mechanism 161. The signal switch 27 is electrically connected to the control module 21, and the signal switch 27 is at least used to output an electrical signal to the control module 21 to enable the control module 21 to control the braking of the motor 13. The signal switch 27 has a first state and a second state, and is triggered by the trigger mechanism 161 to switch between the first state and the second state.

[0037] Optionally, the signal switch 27 is also electrically connected to the power supply circuit connection 25. The signal switch 27 is also used to trigger the power supply circuit 25 to work during the startup process of the power tool 10 so that the power supply circuit 25 provides electrical energy for the control module 21. That is to say, during the startup process of the power tool 10, the signal switch 27 is in a state for triggering the power supply circuit 25 to work, so that the power supply circuit 25 provides electrical energy for the control module 21 and the power tool 10 is powered on; while during the shutdown process of the power tool 10, the signal switch 27 is used to provide a braking signal to the control module 21 to enable the control module 21 to control the braking of the motor 13.

[0038] The power supply circuit 25 is used to convert the electrical energy from the power supply module 24 into electrical energy that can be used by the control module 21 and electrical components. The power supply circuit 25 is connected to the power supply module 24 and the control module 21.

[0039] Optionally, the power tool 10 further includes a signal switch state detection circuit 28. The signal switch state detection circuit 28 is electrically connected to the signal switch 27 and the control module 21. The signal switch state detection circuit 28 is used to detect the state of the signal switch 27 and send the detected state information of the signal switch 27 to the control module 21. The control module 21 controls the braking of the motor 13 according to the state of the signal switch 27.

[0040] Optionally, the power tool 10 further includes a current switch state detection circuit 29. The current switch state detection circuit 29 is electrically connected to the current switch 26 and the control module 21 and is used to detect the on / off state of the current switch 26.

[0041] The control module 21 can receive the electrical signals of the above-mentioned signal switch state detection circuit 28 and current switch state detection circuit 29. The control module 21 controls the operation process of the motor 13 according to the electrical signals received by each switch state detection circuit. By providing the above-mentioned switch state detection circuit, it can effectively avoid the malfunction of the power tool 10 when the mechanical structure of the switch device fails and cannot effectively trigger or mis-trigger the above-mentioned current switch 26 or signal switch 27. Through the software method formed by the above-mentioned hardware switch and switch state detection circuit, a double protection is formed to avoid the unexpected malfunction of the power tool 10.

[0042] Optionally, the signal switch 27 and the current switch 26 are set as an integral structure. Refer to Figure 3 and Figure 4 , as the structure of a specific embodiment of the switch device 16, the signal switch 27 and the current switch 26 are set as an integral structure.

[0043] Refer to Figure 2 and Figure 4 , the switch device 16 specifically includes: a trigger mechanism 161, a switch housing 162, and an actuating pull rod 163. The current switch 26 and the signal switch 27 are arranged in the switch housing 162, and the switch housing 162 is used to accommodate the current switch 26 and the signal switch 27.

[0044] The trigger mechanism 161 is for user operation, and the trigger mechanism 161 is, for example, a trigger. The current switch 26 and the signal switch 27 are arranged in the switch housing 162, and the current switch 26 and the signal switch 27 are associated with the trigger mechanism 161 to be triggered by the trigger mechanism 161.

[0045] The actuating pull rod 163 is connected to the trigger mechanism 161 and can drive along the first direction F1 under the drive of the trigger mechanism 161 ( Figure 7a)Movement. The first end 163a of the actuating rod 163 is connected to the triggering mechanism 161. When the user touches the triggering mechanism 161, it can drive the actuating rod 163 to move relative to the switch housing 162. The actuating rod 163 is also provided with a first elastic element 166 for resetting the actuating rod 163 to its initial position.

[0046] The current switch 26 includes: a movable contact holder 164, a stationary contact 261, and a movable contact 262. For the convenience of description, the moving direction of the actuating rod 163 from the initial position to the final position is defined as the first direction F1 here. Among them, the initial position of the actuating rod 163 refers to the position where the rod 163 is located when the triggering mechanism 161 is not triggered, and the final position of the actuating rod 163 refers to the position where the actuating rod 163 is located when the triggering mechanism 161 is triggered to the end. The position where the triggering mechanism 161 is not triggered is the initial position of the triggering mechanism 161, and the position where the triggering mechanism 161 is triggered to the end is the final position of the triggering mechanism 161.

[0047] Refer to Figure 4 , the movable contact holder 164 is connected to the actuating rod 163 in an associated manner and can move in a direction opposite to the first direction F1 under the drive of the actuating rod 163. In some embodiments, a second elastic element 167 is provided between the movable contact holder 164 and the actuating rod 163, and the actuating rod 163 is connected to the movable contact holder 164 through the second elastic element 167. The second elastic element 167 is, for example, a compression spring or a spring.

[0048] Optionally, the second elastic element 167 is detachably mounted to the movable contact holder 164 and the actuating rod 163. Specifically, a first mounting structure 163c for mounting the second elastic element 167 is provided on the side of the actuating rod 163 facing the movable contact holder 164. Correspondingly, a second mounting structure 164c for mounting the second elastic element 167 is provided on the movable contact holder 164. The second elastic element 167 can be mounted between the movable contact holder 164 and the actuating rod 163 through the first mounting structure 163c and the second mounting structure 164c, and the second elastic element 167 is detachably mounted on the first mounting structure 163c or the second mounting structure 164c. Optionally, the second mounting structure 164c is provided at the middle position of the contact holder 164, and the second elastic element 167 is provided at the middle position of the movable contact holder 164. When the actuating rod 163 moves back and forth in the first direction F1, the movable contact holder 164 can be pushed by the second elastic element 167 to move in a direction opposite to the moving direction of the actuating rod 163, so that the movable contact 162 is in contact connection or disconnection connection with the stationary contact 261.

[0049] As a specific implementation manner, when the second elastic element 167 is a compression spring or a spring, at least one of the first mounting structure 163c and the second mounting structure 164a is a circular convex structure, and the diameter of the circular convex structure is slightly smaller than the diameter of the spring or the compression spring, so that the spring or the compression spring can be mounted.

[0050] Referring to Figure 5 , the moving contact 262 is arranged on the movable contact holder 164, the static contact 261 is arranged in the switch housing 162, and the moving contact 262 and the static contact 261 are arranged corresponding to each other. The moving contact 262 can move relative to the static contact 261 following the movable contact holder 164 to contact or separate from the static contact 261.

[0051] Specifically, the moving contact 262 is arranged at both ends of the movable contact holder 164, the static contact 261 is correspondingly arranged in the switch housing 161. When the movable contact holder 164 moves, it drives the moving contact 262 to move, so as to drive the moving contacts C1, D1, C2, and D2 to contact or separate from the static contacts A1, B1, A2, and B2 respectively. When the actuating pull rod 163 is in its final position, the moving contact 262 and the static contact 261 are in contact, and the current switch 26 is turned on; when the actuating pull rod 163 is in its initial final position, the moving contact 262 and the static contact 261 are separated, and the current switch 26 is turned off.

[0052] Referring to Figure 2 and Figure 4 , optionally, the static contact 261 includes a plurality of static contacts, the moving contact 262 includes a plurality of moving contacts, and the number of the static contacts 261 corresponds to that of the moving contact 262 one by one.

[0053] Optionally, the static contact 261 includes four static contacts, namely two first static contacts A1 and A2, and two second static contacts B1 and B2. Among them, the two first static contacts A1 and A2 are electrically connected to the motor 13. Specifically, the two first static contacts A1 and A2 are electrically connected to the motor 13 through the drive circuit 22. The two static contacts B1 and B2 are electrically connected to the power supply module 24. The two first static contacts A1 and A2 are connected by a first metal sheet, and the two second static contacts B1 and B2 are connected by a first metal conductor.

[0054] The moving contact 262 includes four moving contacts, namely two first moving contacts C1 and C2, and two second moving contacts D1 and D2. Among them, the two first moving contacts C1 and C2 are respectively used to connect to the two first static contacts A1 and A2, and the two second moving contacts D1 and D2 are respectively used to connect to the two second static contacts B1 and B2. The two first moving contacts C1 and C2 are connected by a second metal sheet, and the two second moving contacts D1 and D2 are connected by a second metal sheet.

[0055] In this embodiment, the stationary contact A1 and the stationary contact B1 are the first pair of contacts, and the stationary contact A2 and the stationary contact B2 are the second pair of contacts. The moving contact C1 is used to contact the stationary contact A1, the moving contact D1 is used to contact the stationary contact B1, the moving contact C2 is used to contact the stationary contact A2, and the moving contact D2 is used to contact the stationary contact B2. That is to say, these two pairs of contacts can be connected in parallel through the first metal conductor and the moving contact 262.

[0056] The current switch 26 uses at least two pairs of contacts to carry all the current output by the power supply module 24, which can prevent the contacts of the current switch 26 from arcing due to carrying a large current. In some embodiments, the first metal conductor is a copper sheet. In some embodiments, the second metal conductor is a copper sheet. The two branches connecting the copper sheets bear the current from the power supply module 24 in parallel. Since the copper sheet has good electrical conductivity and good heat dissipation characteristics, in this connection manner, on the one hand, it can effectively solve the arcing phenomenon generated between the switch contacts at the moment of large current connection, and on the other hand, it can also assist in dissipating heat from the current switch by the copper sheet attached to the surface of the switch.

[0057] When the trigger mechanism 161 is actuated to make the moving contact 262 contact and connect with the stationary contact 261, the current switch 26 is turned on, and the electrical connection between the power supply module 24 and the drive circuit 22 is turned on, and the power supply module 24 supplies power to the drive circuit 22 and the motor 13. When the trigger mechanism 161 is released to separate the moving contact 262 from the stationary contact 261, the current switch 26 is turned off, and the power supply module 24 stops supplying power to the drive circuit 22 and the motor 13.

[0058] The signal switch 27 includes: a stop member 165, an elastic conductor 169, a conductive sheet 170, and a PCB circuit board 171.

[0059] For convenience of description, the moving direction of the stop member 165 from the initial position to the final position is defined as the second direction F2 here. Among them, the initial position of the stop member 165 refers to the position where the stop member 165 is located when the trigger mechanism 161 is not triggered, and the final position of the stop member 165 refers to the position where the stop member 165 is located when the trigger mechanism 161 is triggered to the end.

[0060] The stop member 165 is associated with the second end 163b of the actuating pull rod 163. Specifically, a wedge-shaped structure 163d is provided at the second end 163b of the actuating pull rod 163, which is used to abut against and lift the stop member 165 when the actuating pull rod 163 moves towards the stop member 165.

[0061] The stopper 165 is disposed near the second end 163b of the actuating pull rod 163 in the switch housing 162. The stopper 165 can move relative to the switch housing 162 along a second direction F2 that is substantially perpendicular to the first direction F1. The first end 165a of the stopper 165 is disposed in the switch housing 162 through a third elastic element 168. Specifically, the first end 165a of the stopper 165 contacts one end of the third elastic element 168, and the other end of the third elastic element 168 abuts against the inner surface of the switch housing 162. The second end 165b of the stopper 165 can contact the actuating pull rod 163 and the movable contact holder 164 at different times. A groove 164d is provided on the movable contact holder 164 for contacting the stopper 165 when the movable contact holder 164 moves close to the stopper 165. The stopper 165 is also used to abut against the movable contact holder 164 to prevent the first end 164a of the movable contact holder 164 from tilting, so as to avoid misalignment between the moving contact 262 and the stationary contact 261.

[0062] Referring to Figure 6a , an elastic conductor 169 is disposed on the stopper 165. The elastic conductor 169 can move following the stopper 165. The elastic conductor 169 is, for example, a structure in the form of a brush. Referring to Figure 6b , a PCB circuit board 171 is disposed opposite to the elastic conductor 169. A conductive sheet 170 is provided on the PCB circuit board 171. The conductive sheet 170 is disposed near the stopper 165. The elastic conductor 169 can contact the conductive sheet 170. When the stopper 165 moves relative to the switch housing 162 along the second direction F2, the elastic conductor 169 on the stopper 165 slides on the conductive sheet 170. The PCB circuit board 171 is arranged to extend along the moving direction of the stopper 165 and the elastic conductor 169, that is, to extend along the second direction F2, and the conductive sheet 170 is arranged along the moving direction of the elastic conductor 169.

[0063] Optionally, two elastic conductors 169 arranged side by side are provided on the stopper 165, namely a first elastic conductor 169a and a second elastic conductor 169b. The first elastic conductor 169a and the second elastic conductor 169b are connected by a conductor. Optionally, the first elastic conductor 169a and the second elastic conductor 169b are arranged as an integral structure or integrally formed.

[0064] Correspondingly, two first conductive sheets 170a and second conductive sheets 170b arranged side by side are provided on the PCB circuit board 171. The first conductive sheet 170a and the second conductive sheet 170b are insulated from each other. The first conductive sheet 170a is used for contact connection with the first elastic conductor 169a, and the second conductive sheet 170b is used for contact connection with the second elastic conductor 169b.

[0065] The first conductive sheet 170a and the second conductive sheet 170b are respectively connected to the first wire 170c and the second wire 170d, and the first wire 170c and the second wire 170d are connected to an external circuit or electronic components. Optionally, the first wire 170c is electrically connected to at least one of the control module 21, the signal switch state detection circuit 28, and the power supply circuit 25, and the second wire 170d is connected to the power supply of the PCB circuit board, such as 2V, 5V, etc. Optionally, the first wire 170c and the second wire 170d adopt a glue coating treatment method.

[0066] The second conductive sheet 170b has a first part A and a second part B, and the first part A and the second part B are arranged separately from each other. When the second elastic conductor 169b contacts the first part A of the second conductive sheet 170b, the signal switch 27 is in the first state, for example, the off state. When the second elastic conductor 169b contacts the second part B of the second conductive sheet 170b, the signal switch 27 is in the second state, for example, the on state. Optionally, the first part A is independently arranged, and the second part B is connected to an external circuit or electronic components through the second wire 170d, such as the power supply of the PCB circuit board. When the stopper 165 moves from the initial position to the final position along the second direction F2, the second elastic conductor 169b first contacts the first part A and then contacts the second part B. When the stopper 165 moves along the second direction F2 to contact the contact groove 164d, the second elastic conductor 169b contacts the second part B.

[0067] When the signal switch 27 switches from the first state to the second state, the signal switch 27 triggers the power supply circuit 25 to operate so that the power supply circuit 25 supplies power to the control module 24. When the signal switch 27 switches from the second state to the first state, it triggers the control module 21 to control the motor 13 to brake.

[0068] Figures 7a to 7c For the different motion states of the switch device 160 and the states of each switch when the power tool 10 is started. Figures 8a to 8b For the different motion states of the switch device 160 and the states of each switch when the power tool 10 is shut down.

[0069] First, the different motion states of the switch device 160 when the power tool 10 is started will be described below.

[0070] Refer to Figure 7a , when the trigger mechanism 161 is not triggered and is in the initial position, the actuating rod 163 is in the initial position. At this time, the first mounting structure 163c and the second mounting structure 164c are staggered from each other, so that the second elastic element 167 deviates in the direction of the stopper 165.

[0071] The stopper 165 abuts against the second end 163b of the actuating pull rod 163 due to the elastic force of the second elastic element 167. At this time, the stopper 165 is in the initial position, that is, the first position in the second direction F2. At this time, the first elastic conductor 169a on the stopper 165 is in contact with the first conductive piece 170a on the PCB 171, and the second elastic conductor 169b on the stopper 165 is in contact with the first part A of the second conductive piece 170b on the PCB 171. Since the first part A is independently arranged, the signal switch 27 is in the first state, that is, the off state. At this time, the movable contact holder 164 has not yet moved to make the movable contact 262 on the movable contact holder 164 contact and connect with the fixed contact 261 arranged in the switch housing 162, so the current switch 26 is not connected and is in the off state.

[0072] Referring to Figure 7b , when the triggering mechanism 161 is triggered by the user to move the actuating pull rod 163 away from the stopper 165, when the actuating pull rod 163 moves in the first direction F1, when the actuating pull rod 163 moves to a position separated from the stopper 165, due to the lack of support of the actuating pull rod 163, the stopper 165 continues to be pushed by the second elastic element 167 and moves in the second direction F2 to contact the movable contact holder 164. At this time, the stopper 165 is in the second position in the second direction F2. Since at this time, the first mounting structure 163c and the second mounting structure 164c are still staggered from each other, the second elastic element 167 is still deviated in the direction of the stopper.

[0073] At this time, the first elastic conductor 169a on the stopper 165 is in contact with the first conductive piece 170a on the PCB 171, and the second elastic conductor 169b on the stopper 165 is still in contact with the first part A of the second conductive piece 170b on the PCB 171. Since the first part A is independently arranged, no current passes through the signal switch 27, and the signal switch 27 is in the off state. At this time, the movable contact holder 164 has not yet moved to make the movable contact 262 on the movable contact holder 164 contact and connect with the fixed contact 261 arranged in the switch housing 162, so the current switch 26 is not connected and is in the off state.

[0074] When the user continues to press the triggering mechanism 161 to move the actuating pull rod 163 away from the stopper 165, that is, when the actuating pull rod 163 continues to move in the first direction F1, the second elastic element 167 follows the actuating pull rod 163. During the movement of the second elastic element 167, the center line of the second elastic element 167 changes from deviating in the direction opposite to the first direction F1 to being parallel to the second direction F2 and then to deviating in the first direction F1. The second elastic element 167 pushes the movable contact holder 164 to move in the direction of the stopper 165, that is, to move in the direction opposite to the first direction F1.

[0075] Referring to Figure 7c , when the actuating lever 163 moves towards the first direction F1, it drives the second elastic element 167 to push the movable contact holder 164 to move in the direction opposite to the first direction F1, that is, the movable contact holder 164 moves towards the stopper 165. When the second elastic element 167 moves to a position where its center line is deflected towards the first direction F1, the movable contact 261 of the movable contact holder 164 contacts and connects with the fixed contact 261 on the switch housing 162, the current switch 26 is turned on, and the electrical connection between the power supply module 24 and the drive circuit 22 is turned on. When the groove 164d on the movable contact holder 164 moves below the stopper 165, the stopper 165 continues to move towards the first direction F1 from the second position until it abuts against the groove 164d. At this time, the stopper 165 is in the third position, which is also the final position of the stopper 165. At this time, the first elastic conductor 169a on the stopper 165 still contacts the first conductive sheet 170a on the PCB circuit board 171, and the second elastic conductor 169b on the stopper 165 becomes in contact with the second part B of the second conductive sheet 170b on the PCB circuit board 171. Since the second part B is connected to an external circuit or electronic component through a wire, current flows between the elastic conductor 169 and the conductive sheet 170, and the signal switch 27 is switched from the first state to the second state, that is, from the off state to the on state. The signal switch 27 triggers the power supply circuit 25 to work so that the power supply circuit 25 supplies power to the control module 21. When the actuating lever 163 moves towards the first direction F1, the current switch 26 is turned on before the signal switch 27. Optionally, the time interval between the current switch 26 being turned on before the signal switch 27 is less than 20 ms.

[0076] During the process of the actuating lever 163 and the stopper 165 moving from their respective initial positions to their respective final positions, that is to say, during the startup process of the power tool 10, the current switch 26 is turned on first, and the signal switch 27 is turned on later. When the signal switch 27 changes from the first state to the second state, that is, from the off state to the on state, it is used to trigger the power supply circuit 25 to make the power supply circuit 25 work so that the power supply circuit 25 supplies power to the control module 24.

[0077] The following describes the operation process of the switch device 160 and the states of each switch when the power tool 10 is shut down.

[0078] Referring to Figures 8a to 8b, when the user releases the trigger mechanism 161 when the power tool 10 needs to be shut down, the trigger mechanism 161 starts to return. At this time, the actuating rod 163 returns in the direction opposite to the first direction F1. The actuating rod 163 drives the second elastic element 167 to push the movable contact holder 164 to move in the direction opposite to the first direction F1, that is, the movable contact holder 164 moves away from the stopper 165, and the actuating rod 163 moves towards the stopper 165. When the second elastic element 167 moves to a position where its center line is deflected in a direction opposite to the first direction F1, the wedge-shaped structure 163d provided at the first end 163a of the actuating rod 163 contacts the stopper 165. The actuating rod 163 continues to move, and the wedge-shaped structure 163d pushes the stopper 165 to move in the direction opposite to the second direction F2 until the stopper 165 disengages from the groove 164d, and the stopper returns from the third position to the second position and then to the first position (initial position). At this time, the first elastic conductor 169a on the stopper 165 contacts the first conductive sheet 170a on the PCB circuit board 171, and the second elastic conductor 169b becomes in contact with the first part A of the second conductive sheet 170b on the PCB circuit board 171. Since the first part A is independently provided, the signal switch 27 switches from the second state to the first state. At this time, no current flows between the elastic conductor 169 and the conductive sheet 170, and the signal switch 27 changes from the on state to the off state. At this time, the signal switch 27 triggers the control module 27 to control the motor 13 to brake.

[0079] When the actuating rod 163 continues to move towards the stopper 165, the moving contact 262 on the movable contact holder 164 separates from the static contact 261 in the switch housing 162, and the current switch 26 is disconnected, and the electrical connection between the power supply module 24 and the drive circuit 22 is disconnected. That is to say, when the power tool 10 is shut down, the signal switch 27 is disconnected first, and then the current switch 26 is disconnected.

[0080] When the signal switch 27 changes from the first state to the second state, that is, from the off state to the on state, it is used to make the control module 21 control the drive circuit 22 to brake the motor 13. Specifically, during the shutdown process of the power tool, when the signal switch 27 is disconnected, the electrical signal (for example, current signal) generated by it is transmitted to the control module 21. The control module 21 outputs an electrical signal in the form of PWM (Pulse Width Modulation) to the drive circuit 22 according to the electrical signal generated by the triggering of the signal switch 27. The drive circuit 22 brakes the motor 13 according to this electrical signal. Then the user continues to release the trigger mechanism, the current switch 26 is disconnected, and the power tool 10 is powered off and stops.

[0081] The foregoing has shown and described 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. Any technical solutions obtained by means of equivalent replacement or equivalent transformation fall within the protection scope of the present invention.

Claims

1. An electric tool, comprising: A tool accessory; A motor for driving the tool accessory; A power supply module for at least supplying electrical energy to the motor; A drive circuit for loading the electrical energy of the power supply module onto the motor; A control module for controlling the drive circuit; A switch device for controlling the electric tool; Characterized in that the switch device comprises: A trigger mechanism; A current switch for connecting and disconnecting the electrical connection between the power supply module and the motor, the current switch being associated with the trigger mechanism to be triggered by the trigger mechanism; A signal switch for at least outputting an electrical signal to the control module to cause the control module to control the motor to brake, the signal switch being associated with the trigger mechanism to be triggered by the trigger mechanism; An actuating pull rod connected to the trigger mechanism and capable of moving in a first direction under the drive of the trigger mechanism; The current switch comprises: A movable contact holder associated with the actuating pull rod and capable of moving in a direction opposite to the first direction under the drive of the actuating pull rod; A stationary contact provided in the switch housing; A movable contact provided on the movable contact holder, the movable contact being capable of moving relative to the stationary contact following the movable contact holder to contact or separate from the stationary contact.

2. The electric tool according to claim 1, characterized in that It further comprises: A power supply circuit electrically connected to the power supply module and the control module for converting the electrical energy of the power supply module into electrical energy capable of powering the control module; The signal switch is electrically connected to the power supply circuit, and the signal switch is further used to trigger the power supply circuit to work so that the power supply circuit powers the control module.

3. The electric tool according to claim 1, characterized in that The switch device comprises: A switch housing for accommodating the current switch and the signal switch.

4. The electric tool according to claim 3, characterized in that The stationary contact comprises: Two first stationary contacts electrically connected to the motor, and Two second stationary contacts electrically connected to the power supply module; The two first stationary contacts are connected by a metal sheet, and the two second stationary contacts are connected by a metal sheet; The movable contact comprises: Two first movable contacts respectively for connecting to the two first stationary contacts, and Two second movable contacts respectively for connecting to the two second stationary contacts; The two first movable contacts are connected by a metal sheet, and the two second movable contacts are connected by a metal sheet.

5. The electric tool according to claim 3, characterized in that The switch device comprises: A first elastic element provided between the actuating pull rod and the switch housing for resetting the actuating pull rod.

6. The electric tool according to claim 3, characterized in that The switch device comprises: A second elastic element provided between the actuating pull rod and the movable contact holder for enabling the actuating pull rod to drive the movable contact holder to move.

7. The electric tool according to claim 3, characterized in that The current switch comprises: A stopper for abutting against the movable contact frame, the stopper being capable of moving in a second direction substantially perpendicular to the first direction; An elastic conductor disposed on the stopper, the elastic conductor being capable of moving with the stopper; A conductive sheet disposed near the stopper, the conductive sheet being in contact with the elastic conductor; The elastic conductor is capable of moving with the stopper and moving relative to the conductive sheet.

8. The power tool according to claim 7, wherein One end of the actuating pull rod is formed with a wedge-shaped structure for lifting the stopper.

9. The power tool according to claim 7, wherein The elastic conductor includes: A first elastic conductor and a second elastic conductor, the first elastic conductor and the second elastic conductor being connected by a conductor; The conductive sheet includes: A first conductive sheet in contact with the first elastic conductor; a second conductive sheet in contact with the second elastic conductor; The second conductive sheet includes a first portion and a second portion which are separately arranged; When the second elastic conductor is in contact with the first portion, the signal switch is in a first state; When the second elastic conductor is in contact with the second portion, the signal switch is in a second state; When the signal switch is switched from the second state to the first state, it is used to trigger the control module to control the motor brake; When the stopper moves in the second direction, the second elastic conductor first contacts the first portion and then contacts the second portion.

10. The power tool according to claim 9, wherein The movable contact frame is provided with a groove, and when the stopper moves in the second direction to contact the groove, the second elastic conductor contacts the second portion.

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