Nail gun and control method therefor

Abstract

A nail gun (100), comprising: a housing (11); an electric motor (121), which is disposed in the housing; a trigger assembly (16), which is configured, within a nailing cycle, to move from an initial position to a trigger position so as to drive a nail into a workpiece, and to move from the trigger position to the initial position; a parameter measurement unit (21), which is at least connected to the electric motor (121) and measures at least the number of turns of rotation of the electric motor (121); and a controller (23), which is at least connected to the parameter measurement unit (21), wherein the controller (23) is configured to control the electric motor (121) to operate at a constant rotation speed when the number of turns of rotation is greater than or equal to a first number-of-turns threshold value and is less than a second number-of-turns threshold value.

Description

Nail gun and control method thereof

[0001] This application claims the priority of Chinese patent application No. 202311113106.8 filed with the China Patent Office on August 30, 2023, the priority of Chinese patent application No. 202311109669.X filed with the China Patent Office on August 30, 2023, the priority of Chinese patent application No. 202311110798.0 filed with the China Patent Office on August 30, 2023, the priority of Chinese patent application No. 202311107865.3 filed with the China Patent Office on August 30, 2023, the priority of Chinese patent application No. 202311114950.2 filed with the China Patent Office on August 30, 2023, The present application claims priority to the Chinese patent application No. 202311111812.9 filed with the China Patent Office on August 30, 2023, the Chinese patent application No. 202311107885.0 filed with the China Patent Office on August 30, 2023, the Chinese patent application No. 202311224063.0 filed with the China Patent Office on September 21, 2023, the Chinese patent application No. 202311225795.1 filed with the China Patent Office on September 21, 2023, and the Chinese patent application No. 202311226824.6 filed with the China Patent Office on September 21, 2023. The entire contents of the above applications are incorporated herein by reference. Technical Field

[0002] The present application relates to the technical field of electric tools, for example, to a nail gun. Background Art

[0003] Nail guns, as nailing tools, can be mechanical or pneumatic. Typically, after the nail gun is powered on, the firing pin moves downward from its initial position to the firing position, driving the nail. The firing pin is then driven upward by the motor to return to its initial position or near its initial position, a complete nailing cycle. At the end of a nailing cycle, if the firing pin's rest position is too far from its initial position, the next nailing cycle will take longer. If the firing pin's rest position is close to its initial position, the firing pin may not be able to brake in time when it moves to the rest position, resulting in a double nailing, posing a safety hazard.

[0004] This section provides background information related to the present application which is not necessarily prior art.

[0005] Summary of the Invention

[0006] In order to address the deficiencies of the prior art, the present application aims to provide a nail gun with an accurately controlled stop position.

[0007] In order to achieve the above objectives, this application adopts the following technical solutions:

[0008] A nail gun comprises: a housing; a motor disposed within the housing; a firing assembly configured to move from an initial position to a firing position within a nailing cycle to drive a nail into a workpiece, and to move from the firing position to the initial position; a parameter detection unit connected to at least the motor and configured to detect at least the number of rotations of the motor; and a controller connected to at least the parameter detection unit; the controller being configured to control the motor to operate at a constant speed when the number of rotations is greater than or equal to a first threshold value and less than a second threshold value.

[0009] In one embodiment, the first revolution threshold is the number of revolutions of the motor when the motor drives the firing assembly to move from the initial position to the firing position; the second revolution threshold is the number of revolutions of the motor when the controller detects a stop signal.

[0010] In one embodiment, the controller is configured to control the motor to brake at the constant rotation speed as the initial braking speed when the stop signal is detected.

[0011] In one embodiment, the nail gun further includes a power output portion; the power output portion at least includes an energy storage device capable of storing energy during the process of the firing assembly moving from the firing position to the initial position.

[0012] In one embodiment, the parameter detection unit is further configured to detect the energy stored in the energy storage device.

[0013] In one embodiment, the controller is configured to control the speed of the constant speed operation of the motor based at least on the energy stored in the energy storage device.

[0014] In one embodiment, the constant speed of the motor is positively correlated with the energy stored in the energy storage device.

[0015] In one embodiment, the energy storage device is configured as a cylinder; the controller is configured to obtain the air pressure in the cylinder when the number of revolutions of the motor is greater than or equal to a first revolution threshold and less than a second revolution threshold, and set the speed of the motor at a constant speed according to the air pressure.

[0016] In one embodiment, the controller is configured to calculate the kinetic energy of the cylinder according to the gas pressure in the cylinder, and set the constant speed of the motor according to the kinetic energy.

[0017] In one embodiment, the controller is configured to: control the start of the motor in response to a start signal; during the motor start-up process, if the number of rotations is less than or equal to the minimum number of rotations during the motor stall start, limit the maximum duty cycle of the start control signal to be less than or equal to a duty cycle threshold.

[0018] In one embodiment, the controller is configured to set the duty cycle threshold according to at least a battery parameter of the battery pack.

[0019] In one embodiment, the battery parameters of the battery pack include at least one of power level, voltage, temperature, battery cells, and the number of parallel battery cells.

[0020] In one embodiment, the duty cycle threshold has an inverse correlation with at least one battery parameter.

[0021] A nail gun comprises: a housing; a motor disposed within the housing; a firing assembly configured to move from an initial position to a firing position within a nailing cycle to drive a nail into a workpiece, and to move from the firing position to the initial position; a parameter detection unit connected to at least the motor and configured to detect at least an operating parameter of the motor; and a controller connected to at least the parameter detection unit; the controller being configured to control the motor to operate at a constant speed when the operating parameter is greater than or equal to a first parameter threshold and less than a second parameter threshold.

[0022] In one embodiment, the operating parameters of the motor include at least one of the motor's rotation speed, number of revolutions, starting current, and starting voltage.

[0023] In one embodiment, the first parameter threshold is the operating parameter of the motor when the motor drives the firing assembly to move from the initial position to the firing position; the second parameter threshold is the operating parameter of the motor when the controller detects a stop signal.

[0024] A nail gun comprises: a housing; a motor disposed in the housing; a firing assembly configured to move from an initial position to a firing position within a nailing cycle to drive a nail into a workpiece, and to move from the firing position to the initial position; a parameter detection unit connected at least to the motor and configured to detect at least the number of rotations of the motor; a controller connected at least to the parameter detection unit; the controller being configured to: when the number of rotations is greater than or equal to a first threshold value and less than a second threshold value, control the motor to drive the firing assembly at a constant speed until a stop signal is detected.

[0025] In one embodiment, the first revolution threshold is the number of revolutions of the motor when the motor drives the firing assembly to move from the initial position to the firing position; the second revolution threshold is the number of revolutions of the motor when the controller detects a stop signal.

[0026] In one embodiment, the controller is configured to control the motor to brake at the constant rotation speed as the initial braking speed when the stop signal is detected.

[0027] In one embodiment, the nail gun further comprises a power output portion; the power output portion comprises at least an energy storage device capable of storing energy during the movement of the firing assembly from the firing position to the initial position; the controller is configured to control the speed of the motor at a constant speed based at least on the energy stored in the energy storage device.

[0028] A control method for a nail gun, the nail gun comprising a housing; a motor disposed within the housing; a firing assembly configured to move from an initial position to a firing position within a nailing cycle to drive a nail into a workpiece, and to move from the firing position to the initial position; a parameter detection unit connected at least to the motor and configured to detect at least the number of revolutions of the motor; and a controller connected at least to the parameter detection unit. The method comprises: obtaining the number of revolutions of the motor; and controlling the motor to operate at a constant speed when the number of revolutions is greater than or equal to a first revolution threshold and less than a second revolution threshold.

[0029] The benefit of this application is that the moving position of the firing pin in the nail gun can be accurately determined by the number of revolutions of the motor, and when the number of revolutions indicates that the motor is about to stop, the motor is controlled to run at a constant speed, and the motor brake is controlled at a constant speed. The controllability of the brake position is stronger, and the accuracy of the control of the firing pin stop position is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0031] FIG1 is a perspective view of a nail gun from one perspective;

[0032] FIG2 is a cross-sectional view of the nail gun in FIG1 ;

[0033] FIG3 is a schematic diagram of the internal structure of the nail gun in FIG1 in an initial position;

[0034] FIG4 is a schematic diagram of the internal structure of the nail gun in FIG1 in a firing position;

[0035] FIG5 is a perspective schematic diagram of the driving wheel of the nail gun in FIG1 ;

[0036] FIG6 is a perspective view of the nail gun from another perspective;

[0037] FIG7 is a circuit diagram of a nail gun according to an embodiment;

[0038] FIG8 is a flow chart of a method for controlling a nail gun in one embodiment;

[0039] FIG9 is a flow chart of a method for controlling a nail gun in one embodiment;

[0040] FIG10 is a schematic diagram showing the movement position of the firing pin in a nail gun and the number of motor rotations in one embodiment;

[0041] FIG11 is a flow chart of a method for controlling a nail gun in one embodiment;

[0042] FIG12 is a flow chart of a method for controlling a nail gun in one embodiment;

[0043] FIG13 is a schematic diagram showing the relationship between nail gun temperature and minimum nailing time interval in one embodiment;

[0044] FIG14 is a schematic diagram showing the relationship between nail gun temperature and minimum nailing time interval in one embodiment;

[0045] FIG15 is a flow chart of a method for controlling a nail gun in one embodiment;

[0046] FIG16 is a schematic diagram of a state of a backflow prevention structure in one embodiment;

[0047] FIG17 is a schematic diagram of another state of a backflow prevention structure in one embodiment;

[0048] FIG18 is a circuit diagram of a light emitting device control circuit in one embodiment;

[0049] FIG19 is a schematic diagram showing a light emitting device in an embodiment;

[0050] FIG20 is a circuit diagram of a nail gun according to an embodiment;

[0051] FIG21 is a circuit diagram of a nail gun according to an embodiment;

[0052] FIG. 22 is a flow chart of a method for controlling a nail gun in one embodiment. DETAILED DESCRIPTION

[0053] Before any embodiments of the present application are explained in detail, it is to be understood that the application is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the foregoing drawings.

[0054] In this application, the terms "comprises," "includes," "has," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not preclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0055] In this application, the term "and / or" describes a relationship between related objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A exists alone, A and B exist simultaneously, or B exists alone. Additionally, the character " / " in this application generally indicates that the related objects are in an "and / or" relationship.

[0056] In this application, the terms "connect," "combine," "couple," and "install" may refer to direct connection, combination, coupling, or installation, or indirect connection, combination, coupling, or installation. For example, a direct connection refers to two parts or components being connected together without an intermediary, and an indirect connection refers to two parts or components being connected to at least one intermediary, with the two parts or components being connected via the intermediary. Furthermore, "connect" and "couple" are not limited to physical or mechanical connections or couplings and may include electrical connections or couplings.

[0057] In this application, it will be understood by those skilled in the art that relative terms (e.g., "about," "approximately," "substantially," etc.) used in conjunction with quantities or conditions include the values ​​and have the meaning indicated by the context. For example, the relative terms include at least the degree of error associated with the measurement of a specific value, the tolerance caused by manufacturing, assembly, use, etc. associated with a specific value. Such terms should also be considered to disclose a range defined by the absolute values ​​of the two endpoints. Relative terms may refer to plus or minus a certain percentage (e.g., 1%, 5%, 10% or more) of the indicated value. Numerical values ​​that do not use relative terms should also be disclosed as specific values ​​with tolerances. In addition, "substantially" may refer to plus or minus a certain degree (e.g., 1 degree, 5 degrees, 10 degrees or more) on the basis of the indicated angle when expressing a relative angular position relationship (e.g., substantially parallel, substantially perpendicular).

[0058] In this application, it will be understood by those skilled in the art that the function performed by an assembly can be performed by one assembly, multiple assemblies, one part, or multiple parts. Similarly, the function performed by a part can also be performed by one part, one assembly, or a combination of multiple parts.

[0059] In the present application, the terms "upper", "lower", "left", "right", "front", "back" and other directional words are described based on the orientation and positional relationship shown in the accompanying drawings, and should not be understood as limiting the embodiments of the present application. In addition, in the context, it is also necessary to understand that when it is mentioned that an element is connected to another element "upper" or "lower", it can not only be directly connected to the other element "upper" or "lower", but also be indirectly connected to the other element "upper" or "lower" through an intermediate element. It should also be understood that directional words such as upper side, lower side, left side, right side, front side, back side, etc. not only represent the positive orientation, but can also be understood as the lateral orientation. For example, below can include directly below, lower left, lower right, lower front and lower back, etc.

[0060] In this application, the terms "controller," "processor," "central processing unit," "CPU," and "MCU" are used interchangeably. Where a unit "controller," "processor," "central processing unit," "CPU," or "MCU" is used to perform a particular function, unless otherwise specified, the function may be performed by a single unit or multiple units.

[0061] In this application, the terms "device", "module" or "unit" can be implemented in the form of hardware or software to achieve specific functions.

[0062] In this application, the terms "calculate," "determine," "control," "determine," and "identify" refer to the operations and processes of a computer system or similar electronic computing device (e.g., a controller, a processor, etc.). The definitions of up and down, left and right, or front and back in this application can refer to the orientations shown in Figures 1 to 4.

[0063] The nail gun 100 shown in Figures 1 and 2 includes a housing 11, a power output unit 12, a cylinder 13, and a magazine assembly 14. The housing 11 includes a first storage space 111 extending along a first straight line 101 and a second storage space 112 extending along a second straight line 102. In one embodiment, the power output unit 12 can be partially disposed within the first storage space 111 or partially disposed within the second storage space 112. In one embodiment, the power output unit 12 can include a motor 121 or an energy storage device. The energy storage device can be understood as releasing stored kinetic energy during the first half of a nailing cycle to achieve nailing and storing energy during the second half of a nailing cycle to prepare for subsequent nailing. The energy storage device can be a cylinder that can pre-store gas, a cylinder that can be inflated and deflated during operation, or an elastic member such as a spring. In this embodiment, the cylinder 13 serves as the energy storage device and is disposed within the second storage space 112.

[0064] The housing 11 also includes a handle 113 for the user to grasp. A power port 1131 is provided at one end of the handle 113 for connecting to a DC or AC power source. In this embodiment, the power port 1131 is configured to connect to a battery pack 15. A main switch 113a is provided on the handle 113, which the user uses to start and stop the nail gun 100.

[0065] The other end of the handle 113 is connected to the cylinder 13, which extends along the second straight line 102. The first straight line 101 and the second straight line 102 are perpendicular to each other. The clip assembly 14 is arranged along a third straight line 103, which is parallel to the first straight line 101. As an optional embodiment, the clip assembly 14 is also provided with a window 141 through which the user can observe the remaining nails. Window 141 is configured as one or more notches on the clip assembly 14. This allows the user to check the remaining nails and also allows for simple maintenance of the clip assembly 14 without disassembling it.

[0066] A firing assembly 16 is provided in the cylinder 13, and the gas in the cylinder 13 does work, pushing the firing assembly 16 to move and drive out the nail. The nail gun 100 also includes a striking part 17. The striking part 17 is at least partially provided in the cylinder 13, for example, it can be a piston provided in the cylinder 13 and connected to the firing assembly 16. The striking part 17 can be connected to the firing assembly 16, and can strike the firing assembly 16, thereby causing it to move in the cylinder 13. In one embodiment, the cylinder 13 also includes an inflation nozzle, which is configured to pre-fill gas in the cylinder 13. The pre-filled gas reserves a large amount of kinetic energy in a compressed state, and can push the striking part 17 to quickly strike the firing assembly 16 to drive out the nail. Alternatively, the cylinder 13 is a cylinder including an air inlet nozzle and an air outlet nozzle, which does not require pre-filling of gas and can be inflated during the operation of the nail gun 100.

[0067] The following description uses the cylinder 13, which can be pre-filled with gas, as an example. After the nail gun 100 is shut down, the motor 121 stops outputting power, and the firing assembly 16 is stopped at its initial position, with the pre-filled gas in the cylinder 13 in a compressed state. When the nail gun 100 is powered on and the motor is started, the motor 121 outputs power, releasing the firing assembly 16. The striking unit 17 converts the kinetic energy in the cylinder 13 into a striking force that strikes the firing assembly 16, causing the firing assembly 16 to instantly gain a large acceleration and move to the firing position shown in FIG. 4 to drive the nail. After driving the nail, the firing assembly 16, driven by the motor 121, returns from the firing position shown in FIG. 4 to the initial position shown in FIG. 3 and shuts down. During this process, the firing assembly 16 can continuously drive the striking unit 17 to compress the gas in the cylinder 13. The above-mentioned process from starting the nail gun to nailing, and the firing assembly 16 returning to its initial position or near its initial position, i.e., the shutdown position, is referred to as a nailing cycle. It should be noted that the initial position shown in FIG3 is the position where the firing assembly 16 stops after the nail gun 100 is shut down, and therefore can also be referred to as the stop position. The position to which the firing assembly 16 can move upward is referred to as the top dead center, and the position to which the firing assembly 16 can move downward is referred to as the bottom dead center. The firing position and the bottom dead center can be the same position, and the initial position is closer to the top dead center from the bottom up, but is not the top dead center, that is, the distance between the initial position and the top dead center is greater than zero.

[0068] As shown in Figure 2, the motor 121 extends substantially along the first straight line 101, and the cylinder 13 and the firing assembly 16 disposed in the cylinder 13 extend substantially along the second straight line 102. The motor 121 and the cylinder 13 are disposed substantially vertically. The motor 121 can be used as a power source to drive the motor 121 to drive the firing assembly 16 to move within the cylinder 13. In an optional implementation, the motor 121 can be a part of the motor 121. It can output power to a drive shaft 124, and a drive wheel 125 is disposed on the drive shaft 124. The firing assembly 16 comprises at least a striker 161. In one embodiment, the firing assembly 16 may also include a striking portion 17, wherein the striking portion 17 may be a piston connected to the top end of the striker 161. The piston and the striker 161 are fixedly connected or detachably connected. The striking portion 17 can compress the pre-charged gas within the cylinder 13 when the striker 161 is driven to move upward, i.e., to its initial position. The firing pin 161 is formed with a transmission tooth 161a, which can move within the cylinder 13 along the second straight line 102, which can be understood as the nailing direction. The drive wheel 125 can cooperate with the transmission tooth 161a to drive the firing assembly 16 to overcome the air pressure in the cylinder 13, thereby causing the firing assembly 16 to enter the initial position shown in Figure 3.

[0069] As shown in Figures 4 and 5, the drive wheel 125 is a gear structure. It also has a second connecting hole 125a for connecting the drive shaft 124. The second connecting hole 125a is specifically a flat hole. When the drive shaft 124 is connected to the second connecting hole 125a, the drive wheel 125 rotates synchronously with the drive shaft 124. A plurality of drive teeth 125g are formed around the main body of the drive wheel 125. The drive teeth 125g include a first tooth 125b located at the starting end and a second tooth 125d located at the end. Here, the drive tooth 125g that first contacts the firing pin 161 of the firing assembly 16 when the drive wheel 125 begins to drive the firing assembly 16 back to the initial position shown in Figure 3 is defined as the first tooth 125b, and the drive tooth 125g that last engages the firing pin 161 of the firing assembly 16 after the firing assembly 16 is in the initial position is defined as the second tooth 125d. Between the first tooth 125b and the second tooth 125d is a first section 125e and a second section 125f. The first section 125e is evenly distributed with multiple drive teeth 125g; the second section 125f is smooth and continuous and has no drive teeth 125g. When the drive teeth 125g of the first section 125e engage with the transmission teeth 161a on the striker 161, the drive wheel 125 can drive the striker 161 to compress the gas in the cylinder 13 to perform work. When the second section 125f engages with the striker 161, due to the smoothness and continuity of the second section 125f, the striker 161, without the drive teeth 125g to stop it, will be quickly pushed out by the gas in the cylinder 13, thereby achieving the nailing effect.

[0070] In other embodiments, the driving wheel 125 may also be a driving component in other forms. This application does not specifically limit the structural forms of other possible driving wheels 125.

[0071] In this embodiment, a light-emitting device 18 is provided on the nail gun 100. The light-emitting device 18 can be one or more LED lamp beads arranged at different positions, or a row of light strips, or a digital tube, or a display screen, etc. As shown in Figure 6, the light-emitting device 18 is three LED lights arranged on the shell 11. Among them, one light-emitting device 181 is arranged directly above the horizontal plane where the firing pin 161 is located, and the other two light-emitting devices 182 can cooperate with the light-emitting device 181 to project a V-shaped, arrow-shaped or triangular light spot on the workpiece to be nailed, and the light spot can indicate the nailing position on the workpiece. In one implementation, the other two light-emitting devices 182 are arranged on the shell 11 on the left and right sides of the front end of the nail gun 100.

[0072] It is known that after a nail gun has been used for a long time, the cylinder 13 may leak due to problems such as material or sealing. If the cylinder 13 leaks, the pre-filled gas in the cylinder 13 will be reduced, or the cylinder 13 may be under-inflated during operation. In short, the kinetic energy of the compressed gas will be reduced, thereby affecting the nailing force or depth of the nail gun. Moreover, when the motor 121 drives the firing assembly 16 back to the initial position, i.e., the stop position, under the same power, the motor 121 may not stop even after reaching the initial position due to the reduction of gas in the cylinder 13, posing a certain safety hazard. For nail guns whose energy storage device is an elastic member such as a spring, they will also face the problem of the spring elastic force decaying after being used for a long time, resulting in a reduction in the kinetic energy, i.e., the elastic energy, of the spring after compression, which will also affect the nailing force or depth, or bring certain safety hazards.

[0073] In order to solve the above problems, it is necessary to accurately detect whether the cylinder is leaking or whether the spring force is attenuated, and to promptly alarm and repair after confirming that the cylinder is leaking or the spring force is attenuated.

[0074] Referring to the nail gun control circuit 200 shown in FIG7 , it may include at least a parameter detection unit 21, a drive circuit 22, a controller 23, a light-emitting device 18, and a motor 121. The battery pack 15, serving as the power source for the control circuit 200, not only provides driving power for the motor 121 but also provides low-voltage power to the controller 23 after conversion by the power conversion unit, or provides power to the parameter detection unit 21, or provides power to the light-emitting device 18. This embodiment only illustrates the power supply path through which the battery pack 15 provides power to the motor 121; other possible power supply paths are not described in detail.

[0075] In one embodiment, the drive circuit 22 is connected between the controller 23 and the motor 121. It receives control signals from the controller 23 and controls the operating state of the motor 121 by changing its conduction state, for example, to control the motor 121 to stop, start, rotate, or change speed or direction. Optionally, the drive circuit 22 may be composed of one or more power elements. In one embodiment, as shown in FIG7 , the drive circuit 22 includes multiple power elements VT1, VT2, VT3, VT4, VT5, and VT6. Each gate terminal of each power element is electrically connected to the controller 23 and configured to receive control signals from the controller 23. Each drain or source terminal of each power element is connected to the stator winding of the motor 121. Power elements VT1-VT6 receive control signals from the controller 23 to change their conduction states, thereby changing the current applied by the battery pack to the stator winding of the motor 121. In one embodiment, the drive circuit 22 may be a three-phase bridge driver circuit comprising six controllable semiconductor power devices (e.g., FETs, BJTs, IGBTs, etc.). It is understandable that the above-mentioned power element may also be any other type of solid-state switch, such as an insulated gate bipolar transistor (IGBT), a bipolar junction transistor (BJT), etc.

[0076] To rotate the motor 121, the drive circuit 22 has multiple drive states. In one drive state, the stator winding of the motor generates a magnetic field. The controller 23 outputs a corresponding PWM control signal to the switching element in the drive circuit based on the rotor position or back electromotive force of the motor, causing the drive circuit to switch the drive state, thereby causing the stator winding to generate a changing magnetic field to drive the rotor to rotate, thereby achieving rotation or phase change of the motor. It should be noted that any other circuit and control method capable of driving the rotation or phase change of the motor can be used in the present disclosure. The present disclosure does not limit the circuit structure of the drive circuit 22 or the control of the drive circuit 22 by the controller 23.

[0077] The parameter detection unit 21 can at least detect the operating parameters of the motor 121, or detect the electrical parameters of the battery pack 15. In one embodiment, the parameter detection unit 21 can detect the output current, output voltage, or output power of the motor 121, or the working time of the motor 121 in a nailing cycle, i.e., the time of the nailing cycle, or the nailing frequency, or the number of revolutions of the motor in a nailing cycle, etc. In one embodiment, the parameter detection unit 21 can also detect the battery parameters of the battery pack 15, such as detecting the output voltage, current, power consumption, or power consumption of the battery pack in a nailing cycle. It is understandable that the parameter detection unit 21 may include one or more detection devices, which can detect a variety of different operating parameters or battery parameters separately or simultaneously.

[0078] In this embodiment, if the cylinder 13 is not leaking or the spring force is not attenuated, the output energy of the motor 121 during each nailing cycle is substantially the same, and the energy consumption of the battery pack 15 during each nailing cycle is substantially the same. If the cylinder 13 is leaking or the spring force is attenuated, the energy required by the motor 121 to drive the firing assembly 16 and the power unit 17 to gradually compress the gas or spring during any nailing cycle will be reduced, and the energy consumption of the battery pack 15 will also be reduced. In other words, by analyzing the output energy of the motor 121 and / or the energy consumption of the battery pack 15 during at least one nailing cycle, an accumulation or integration of the motor energy or battery pack energy over a time period can be formed, thereby avoiding the low reliability of comparing energy, current, voltage, or power at discrete moments, thereby more accurately determining whether the cylinder 13 is leaking or the spring force is attenuated.

[0079] In this embodiment, the controller 23 is capable of obtaining at least the operating parameters of the motor 121 and / or the electrical parameters of the battery pack 15, and can then determine the output energy of the motor 121 during at least one nailing cycle or the energy loss of the battery pack 15 during at least one nailing cycle based on the obtained parameters. For example, the controller 23 can calculate the output energy of the motor 121 during a nailing cycle based on the product of the output current and output voltage of the motor 121 during the nailing cycle and the duration of the cycle.

[0080] It should be noted that the air pressure in the cylinder 13 changes with the movement of the firing assembly 16 in the cylinder 13 during a nailing cycle, and the average air pressure in the cylinder 13 during a nailing cycle can be considered to be basically unchanged. If the cylinder 13 leaks, the air pressure in the cylinder decreases, that is, the air pressure at any time or the average air pressure in a nailing cycle will decrease, then the output energy of the motor 121 in a nailing cycle will decrease, or the energy consumption of the battery pack 15 in a nailing cycle will decrease. In other words, the output energy of the motor 121 in a nailing cycle, or the energy consumption of the battery pack 15 in a nailing cycle is positively correlated with the air pressure in the cylinder 15, or at least positively correlated with the average air pressure of the cylinder 13 in a nailing cycle. In one embodiment, the above positive correlation can be linear or nonlinear. Based on this relationship, the controller 23 can determine the air pressure of the cylinder 13, or at least determine the magnitude of the air pressure of the cylinder 13 within a nailing cycle, based on the output energy of the motor 121 and / or the energy consumption of the battery pack 15 within at least one nailing cycle currently calculated. Similarly, when the energy storage device is a spring, the output energy of the motor 121 within a nailing cycle, or the energy consumption of the battery pack 15 within a nailing cycle, is positively correlated with the elastic force of the spring, or at least is positively correlated with the average air pressure of the spring within a nailing cycle. In one embodiment, the above positive correlation can be linear or nonlinear. Based on this relationship, the controller 23 can determine the elastic force of the spring, or at least determine the magnitude of the elastic force of the spring within a nailing cycle, based on the output energy of the motor 121 and / or the energy consumption of the battery pack 15 within at least one nailing cycle currently calculated. In this embodiment, the air pressure of the cylinder 13 or the elastic force of the spring can be understood as the kinetic energy of the energy storage device or at least corresponds to the kinetic energy of the energy storage device.

[0081] Assuming cylinder 13 is leak-free, the output energy of motor 121 during a nailing cycle is W11, or the energy loss of battery pack 15 during a nailing cycle is W21, and the average pressure in cylinder 13 is Pa1. If cylinder 13 leaks, the output energy of motor 121 during a nailing cycle is W12, or the energy loss of battery pack 15 during a nailing cycle is W22, and the average pressure in cylinder 13 is Pa2. Therefore, W12 is less than W11, W22 is less than W21, and Pa2 is less than Pa1.

[0082] In one embodiment, the controller 23 may set the average air pressure Pa1 of the cylinder 13 during a nailing cycle when the cylinder 13 is leak-free as the air pressure threshold. If the air pressure in the cylinder 13 is determined to be less than the air pressure threshold based on the output energy of the motor 121 during a nailing cycle and / or the energy consumption of the battery pack 15 during a nailing cycle, it can be determined that the cylinder 13 has an air leak, and the controller 23 may control the motor 121 to stop operating, for example, by powering off the motor 121 or stopping the output of the control signal.

[0083] In one embodiment, the controller 23 can also control the light-emitting device 18 to display different prompt information after determining the relationship between the air pressure in the cylinder 13 and the air pressure threshold. For example, when the air pressure is lower than the low pressure threshold, the cylinder 13 may have an air leakage problem. The controller 23 can control the light-emitting device 18 to output prompt information in a first manner, wherein the first manner may include at least one of the number of light-emitting devices, light-emitting color, light-emitting frequency, brightness level, and light-emitting display content. When the air pressure is substantially equal to the air pressure threshold, the controller 23 can control the light-emitting device 18 to not emit light or to emit light in a second manner that is different from the first manner. When the air pressure is greater than the air pressure threshold, the controller 23 can control the light-emitting device 18 to emit light in a second manner that is different from the first manner and the second manner.

[0084] Similarly, the determination or early warning method of the spring elastic force can also refer to the determination or early warning method of the air pressure in the cylinder 13, which will not be repeated here.

[0085] Referring to a control process of a nail gun shown in FIG8 , the process may include at least the following steps:

[0086] S101, obtaining operating parameters of a motor in at least one nailing cycle.

[0087] S102: Determine the air pressure in the cylinder according to the working parameters in at least one nailing cycle.

[0088] S103, when the air pressure is lower than the air pressure threshold, the motor is controlled to stop working.

[0089] Referring to a control process of a nail gun shown in FIG9 , the process may include at least the following steps:

[0090] S201: Acquire operating parameters of a motor and / or electrical parameters of a battery pack in at least one nailing cycle.

[0091] S202: Determine the air pressure in the cylinder according to the working parameters and / or electrical parameters in at least one nailing cycle.

[0092] S203: Determine the relationship between the air pressure in the cylinder and the air pressure threshold.

[0093] S204: When the air pressure in the cylinder is less than the air pressure threshold, control the light emitting device to output prompt information in a first manner.

[0094] S205: When the air pressure in the cylinder is substantially equal to the air pressure threshold, control the light emitting device to output prompt information in a second manner.

[0095] S206: When the air pressure in the cylinder is greater than the air pressure threshold, control the light emitting device to output prompt information in a third manner.

[0096] It is understood that after a nailing cycle of the nail gun is completed, the firing pin 161 stops at the stop position. Generally, the controller 23 can determine whether to stop the machine based on the operating time of the motor 121 after it is powered on. For example, if a nailing cycle is T, the controller 23 can control the motor 121 to stop after it has rotated for T1 time. However, if the motor speed is too high, when the nail gun stops at the preset stop time, the firing pin 161 may reach the stop position but the motor has not completely stopped rotating. As a result, the firing pin 161 may be driven to continue moving to the initial position, or even double-strike.

[0097] Since the correspondence between the number of revolutions of the motor 121 and the position of the striker 161 will not be affected by the motor speed or other factors, in order to accurately control the stop position of the striker 161, the present application can control the stop position of the striker 161 according to the number of revolutions of the motor 121. In one embodiment, referring to the control circuit shown in FIG7 , the parameter detection unit 21 can also detect the number of revolutions of the motor 121. For example, the parameter detection unit 21 can count from zero after the motor is started, and calculate the number of revolutions of the motor according to the number of motor commutations. The controller 23 can determine the timing of controlling the motor to run at a constant speed according to the number of revolutions of the motor, and ensure that the motor runs at a constant speed before stopping, thereby ensuring the accuracy of the stop position control.

[0098] Referring to Figure 10 , the relationship between the position of the striker 161 and the number of motor revolutions during a nailing cycle is illustrated, using any physical point on the striker 161 as a reference point. In Figure 10 , the number 0 represents the number of motor revolutions when the motor is just powered on and the striker 161 is in its initial position, or rest position. N1 represents the number of motor revolutions when the motor 121 drives the striker 161 from its initial position to its firing position. N2 represents the number of motor revolutions when the motor 121 drives the striker 161 from its initial position to its firing position and then returns to its rest position. N3 represents the number of motor revolutions when the striker 161 triggers a stop signal during its return from the firing position to its initial position. It is understood that a Hall sensor can be provided on the drive wheel 125 to detect the position of the striker 161, triggering a stop signal when the striker 161 reaches a preset position. The controller 23 can control the motor 121 to stop in response to the stop signal.

[0099] In this embodiment, the controller 23 can control the motor 121 to run at a constant speed when the number of revolutions of the motor 121 is greater than or equal to a first revolution threshold and less than a second revolution threshold. The first revolution threshold may be the number of revolutions N1 in FIG10 , and the second revolution threshold may be the number of revolutions N3 in FIG10 . In other words, the controller 23 can control the motor 121 to run at a constant speed in advance before the stop signal is detected until the stop signal is detected, thereby ensuring that the speed of the motor is stable when braking. A stable or constant initial braking speed can ensure that the number of revolutions of the motor 121 from the start of braking to the stop of rotation is stable, thereby ensuring that the striker 161 can be stably stopped at the stop position.

[0100] In other embodiments, the controller 23 can also control the motor 121 to run at a constant speed until the stop signal is detected by other means, so as to have a stable initial braking speed and ensure that the striker 161 can be stably stopped at the stop position.

[0101] In one embodiment, the controller 23 can control the speed of the motor 121 during constant speed operation based on the energy stored in the energy storage device. Generally, the greater the energy stored in the energy storage device, the higher the speed of the motor during constant speed operation, and vice versa. In other words, there is a positive correlation between the energy currently stored in the energy storage device and the speed of the motor during constant speed operation.

[0102] In this embodiment, the energy storage device is set as the cylinder 13. When the number of revolutions of the motor 121 is greater than or equal to the first revolution threshold and less than the second revolution threshold, the controller 23 can obtain the air pressure in the cylinder 13 and set the speed of the motor at constant speed according to the air pressure, or the controller 23 can calculate the kinetic energy in the cylinder 13 according to the air pressure in the cylinder 13, and set the speed of the motor at constant speed according to the kinetic energy. In one implementation, the kinetic energy in the cylinder 13 can be the kinetic energy at the current moment, or it can be the average kinetic energy of the cylinder 13 in one nailing cycle. In one implementation, the controller 23 can calculate the air pressure in the cylinder 13 by using the output energy of the motor 121 in at least one nailing cycle and / or the energy consumption of the battery pack 15 in at least one nailing cycle as described in the above embodiment, which will not be repeated here.

[0103] Referring to FIG. 11 , a control process of a nail gun may include at least the following steps:

[0104] S301, obtaining the number of rotations of the motor.

[0105] S302 , when the number of rotations is greater than or equal to a first threshold value and less than a second threshold value, controlling the motor to operate at a constant speed.

[0106] S303: When a brake signal is detected, braking is performed at a constant rotation speed as an initial braking speed.

[0107] Some power tools, such as nail guns, reciprocating saws, and jigsaws, require rapid acceleration upon startup. Rapidly starting power tools requires increasing the start signal's duty cycle to a target value, such as maximum, within a short period of time. However, rapid startup of power tools involves high starting currents. If the tool encounters a stall or heavy load during startup, it could burn out. Especially for power tools like nail guns that require frequent starts and stops, safe and rapid startup is a crucial performance indicator for proper operation.

[0108] In order to avoid the above problems, this embodiment takes a nail gun as an example to provide a control method for starting an electric tool.

[0109] Continuing to refer to the control circuit of the nail gun shown in Figure 7, the parameter detection unit 21 can detect the operating parameters of the motor 121, at least the operating parameters during the startup process of the motor 121. For example, the parameter detection unit 21 can detect one or more of the speed, number of revolutions, starting current or starting voltage of the motor 121. The controller 23 can set the maximum duty cycle of the control signal for controlling the startup of the motor 121 based on the obtained operating parameters of the motor 121. In this embodiment, by adjusting the maximum duty cycle of the motor startup control signal based on the operating parameters of the motor, damage to the power tool can be avoided when the power tool is forced to start due to stalling or heavy load during the startup process.

[0110] During the startup of the motor 121, if the controller 23 detects that the operating parameters of the motor 121 are less than or equal to the parameter threshold, it can be considered that the motor 121 may be starting with a heavy load or may have stalled during the startup process, and the maximum duty cycle of the startup control signal can be set to be less than or equal to the duty cycle threshold. It is understood that the parameter thresholds of the motor operating parameters can be set differently in different types of power tools. For example, the parameter threshold can be the minimum speed or minimum number of revolutions of the motor 121 when starting with a stall, or the minimum speed or minimum number of revolutions of the motor when starting with a heavy load.

[0111] In one embodiment, the controller 23 can set a duty cycle threshold based on the battery parameters of the battery pack 15. For example, the duty cycle threshold can be set based on at least one of the battery pack's charge level, voltage, temperature, battery cells, or the number of parallel cells. In this embodiment, the duty cycle threshold is inversely correlated with the at least one battery parameter. For example, the lower the voltage of the battery pack 15, the larger the duty cycle threshold. For example, the nail gun 100 is typically powered by a 24V battery pack. If the controller 23 detects that the voltage of the battery pack 15 is below 24V, it sets the duty cycle threshold of the start control signal to 100%. This allows the duty cycle of the start control signal to increase to a maximum of 100% when the operating parameters of the motor 121 are less than or equal to the parameter threshold. If the controller 23 detects that the voltage of the battery pack 15 is above 24V, it sets the duty cycle threshold of the start control signal to less than 100%, for example, to 60%. This allows the duty cycle of the start control signal to increase to a maximum of 60% when the operating parameters of the motor 121 are less than or equal to the parameter threshold. This ensures that when the power tool is installed with battery packs of different voltages or capacities, the starting performance of the power tool is basically the same, and also increases the machine's anti-blocking ability.

[0112] Referring to FIG. 12 , a control process of a nail gun may include at least the following steps:

[0113] S401, monitoring the operating parameters of the motor during the motor startup process.

[0114] S402: If the operating parameter of the motor is less than or equal to the parameter threshold, limit the maximum duty cycle of the start control signal to be less than or equal to the duty cycle threshold.

[0115] S403: Obtain battery parameters of the battery pack.

[0116] S404: Setting a duty cycle threshold according to battery parameters.

[0117] The order of some or all of the process steps in the flowcharts of this application is not limited to the steps defined in the flowcharts, as the order of the steps can be parallel or interchangeable. For example, steps S403 and S404 can be parallel or interchangeable with step S401.

[0118] The nail gun 100 typically operates in an environment requiring continuous and sustained nailing. After prolonged operation, the temperature of components such as the cylinder 13 or the motor 121 may rise excessively. For example, the temperature of the motor 121 may reach 150°C. If the nail gun 100 continues to operate rapidly at excessively high temperatures, it is likely to burn out some internal components, such as circuit boards or cause a motor short circuit. Therefore, the present application provides a nail gun that can detect temperature and control the activation frequency or activation interval of the nail gun.

[0119] Continuing with reference to the control circuit of the nail gun 100 shown in FIG7 , the parameter detection unit 21 may include a temperature detection unit capable of detecting temperature data, and may be capable of detecting the temperature at at least one location within the nail gun 100. In this embodiment, the temperature detection unit may be one or more temperature sensors, such as a thermistor sensor, a thermocouple sensor, a temperature sensor, a platinum resistance temperature sensor, and a digital output sensor.

[0120] In one embodiment, the temperature detection unit can detect the temperature of the motor 121, for example, it can detect the temperature of the motor stator or rotor, or the temperature detection unit can detect the temperature of the circuit board where the control circuit is located or the temperature of the power components on the circuit board, or it can detect the temperature inside the cylinder 13 or the temperature of the cylinder wall or the temperature of the striking part 17, or it can detect the temperature of the firing pin 161, or it can detect the temperature of the piston, or it can detect the temperature of the air outlet provided on the housing 11 of the nail gun 100, where the air outlet can be a heat dissipation port provided near the motor 121, or a heat dissipation port provided near the circuit board, etc. In other embodiments, the temperature detection unit can also detect the temperature of any other position of the nail gun 100, which will not be listed here one by one. The temperature described in this embodiment can be understood as the temperature of at least one position or component of the nail gun 100.

[0121] In this embodiment, the controller 23 can obtain the temperature detected by the temperature detection unit and adjust the minimum nailing time interval of the nail gun 100 based on the relationship between the temperature and the set temperature threshold. It should be noted that the time interval between the end of one nailing cycle and the beginning of the next nailing cycle of the nail gun 100 can be referred to as the nailing time interval, and the minimum nailing time interval can be understood as the minimum time interval between two adjacent nailing cycles. In this embodiment, the start time of a nailing cycle can be the time when the controller 23 detects the start signal, and the end time of a nailing cycle can be the time when the controller 23 detects the stop signal. Therefore, a nailing time interval can be the time period from the time when the controller 23 detects the stop signal in the previous nailing cycle to the time when the controller 23 detects the start signal at the beginning of the next nailing cycle.

[0122] Since the nailing frequency can be understood as the number of nailing times per unit time, the nailing time interval and the nailing frequency can be replaced in some embodiments. For example, the controller 23 can adjust the nailing frequency of the nail gun 100 according to the temperature of the nail gun 100.

[0123] In one embodiment, the controller 23 can set the minimum nailing time interval to T1 when the temperature of at least one location on the nail gun 100 is less than or equal to a temperature threshold, and set the minimum nailing time interval to T2 when the temperature is greater than the time threshold, with T2 being greater than T1. Alternatively, the controller 23 can set the maximum nailing frequency to f1 when the temperature of at least one location on the nail gun 100 is less than or equal to the temperature threshold, and set the maximum nailing frequency to f2 when the temperature is greater than the time threshold, with f2 being less than f1. It is understood that after the temperature of the nail gun 100 exceeds a predetermined value, the minimum nailing time interval of the nail gun 100 increases, or in other words, the nailing frequency of the nail gun decreases. For example, when the temperature of the nail gun 100 is less than or equal to 100°C, the minimum nailing time interval is 1s. This means that when the temperature of the nail gun 100 is less than or equal to 100°C, the time interval between any two adjacent nailing cycles is greater than or equal to 1s. When the temperature of the nail gun is greater than 100° C., the minimum nailing time interval is 2 seconds. It can be understood that when the temperature of the nail gun 100 is greater than 100° C., the nailing time interval between any two adjacent nailing cycles is greater than or equal to 2 seconds.

[0124] In one embodiment, the temperature of the nail gun 100 has a positive correlation with the minimum nailing interval. For example, as the nail gun temperature increases, the minimum nailing interval set by the controller 23 increases. In one embodiment, as shown in FIG13 , the nail gun temperature and the minimum nailing interval have a linear relationship. The horizontal axis represents the nail gun temperature t, and the vertical axis represents the minimum nailing interval TI. Within the temperature range where the nail gun temperature is less than the temperature threshold t0, the minimum nailing interval TI can be a fixed value. However, after the nail gun temperature is greater than or equal to the temperature threshold, the minimum nailing interval TI increases as the temperature t increases, essentially exhibiting a linear relationship. In one embodiment, as shown in FIG14 , the nail gun temperature and the minimum nailing interval have a step-like relationship. That is, the minimum nailing interval for any temperature within a certain temperature range is the same. In other embodiments, the nail gun temperature and the minimum nailing interval may have other varying relationships. It is understood that the nail gun temperature may have an inverse correlation with the maximum nailing frequency, that is, as the nail gun temperature increases, the maximum nailing frequency set by the controller 23 decreases.

[0125] In one embodiment, if the controller 23 detects a start signal and determines that the time between the start signal and the last stop signal received is less than the minimum nailing time interval, the start signal may be ignored, i.e., the motor 121 may not be controlled to start, or the motor 121 may not be controlled to start, or the motor 121 may not be powered on, or the drive signal to drive the motor 121 may not be output. If the controller 23 detects a start signal and determines that the time between the start signal and the last stop signal received is greater than or equal to the minimum nailing time interval, the motor 121 may be controlled to start.

[0126] In this embodiment, when the temperature of the nail gun exceeds a certain value, by extending the minimum nailing time interval or reducing the nailing frequency, the nail gun can be given a certain amount of time to dissipate heat or cool down, so that it will not continue to work in a high temperature state for a short period of time, thereby improving the safety of the nail gun and ensuring the working performance of the nail gun.

[0127] Referring to FIG. 15 , a control process of a nail gun may include at least the following steps:

[0128] S501, obtaining the temperature of the nail gun.

[0129] S502: When the temperature of the nail gun is less than or equal to the temperature threshold, the minimum nailing time interval of the nail gun is set to T1.

[0130] S503: When the nail gun temperature is greater than the temperature threshold, the minimum nailing time interval is set to T2.

[0131] In one embodiment, in order to prevent the firing pin 161 from sliding down during the process of the firing pin 161 moving from the firing position to the initial position or after the nail gun 100 is stopped, the anti-return structure 19 shown in Figures 16 and 17 can be used to stop or lock the firing pin.

[0132] Continuing with Figures 16 and 17 , the anti-return structure 19 may include a solenoid 191, an elastic member 192, a push rod 193, and a stopper 194. The solenoid 191 is electrically connected to at least one controller 23, which can control whether the solenoid 191 is powered on or off. As shown in Figure 16 , when the solenoid 191 is de-energized, the elastic member 192 is extended, and the stopper 194 connected to the push rod 193 engages with the anti-return tooth 162 on the other side of the striker 161, preventing the striker 161 from slipping out of its initial position. When the nail gun's power-on motor 121 is powered on, the solenoid 191 is energized. The electromagnetic effect generated causes the push rod 193 to compress in the first direction 1, allowing the stopper 194 to rotate clockwise, disengaging from the anti-return tooth 162. Unobstructed, the striker 161 can be driven by the power within the cylinder 13 to drive the nail.

[0133] That is to say, when the solenoid 191 is energized, the stopper 194 is in an invalid state, that is, the stopper 194 cannot lock the firing pin 161 or does not contact the firing pin 161, and the firing pin 161 can move from the initial position to the firing position to nail under the drive of the driving force 125; and when the solenoid 191 is de-energized, the stopper 194 is in a stop state, that is, the stopper 194 can lock the firing pin 161 in the initial position, or at least prevent the firing pin 161 from slipping during the process of moving from the firing position to the initial position.

[0134] If the solenoid 191 cannot be effectively activated in time to put the stopper 194 in a stopped state when the firing pin 161 moves to the initial position after nailing, the firing pin 161 may accidentally slip, which may cause continuous nailing or other safety accidents.

[0135] To address the above issues, referring again to the nail gun control circuit diagram shown in FIG7 , the parameter detection unit 21 therein is capable of detecting the number of revolutions of the motor 121. When the motor 121 is started, the controller 23 controls the solenoid 191 to be energized, the stopper 194 to be in a disabled state, and the firing pin 161 to be able to move from the initial position to the firing position. After the motor 121 is powered on, the controller 23 continuously monitors the number of revolutions of the motor 121. When the number of revolutions exceeds a threshold, the controller 23 controls the solenoid 191 to be de-energized, thereby operating the stopper 194 in a stopped state. This prevents the firing pin 161 from slipping during its upward return to its initial position and locks the firing pin 161 in its initial position. In other words, after the nail gun 100 is shut down, the solenoid 191 remains de-energized. Even if the nail gun 100 is inactive for an extended period, the check mechanism 19 will not energize the solenoid 191 to lock the firing pin 161, thereby preventing the solenoid from operating at high temperatures for extended periods. In this embodiment, the threshold number of revolutions of the motor 121 can be the number of revolutions of the motor 121 after it is started and the striker 161 reaches the firing position. Since the displacement of the striker 161 is constant when the motor 121 rotates a certain number of revolutions, controlling the solenoid power supply by the number of revolutions of the motor ensures that the striker can be locked by the solenoid while preventing the solenoid from heating due to prolonged power supply.

[0136] It is understood that during the downward movement of the striker 161 from the initial position to the firing position, the striker 161 rapidly drives the nail using the power stored in the energy storage device, i.e., the cylinder 13. During this process, the driving force 125 is not engaged with the striker 161, and the motor 121 drives the drive wheel 125 to rotate. After nailing, as the striker 161 moves upward from the striking position, the drive wheel 125 engages with the striker 161. Driven by the drive wheel 125, the striker 161 moves upward, and the motor 121 shifts from not driving the striker 161 to driving it. This changes the operating state of the motor 121, and significantly alters the operating parameters of the motor 121. For example, as the striker 161 begins to move upward from the firing position, the operating current, output torque, or speed of the motor 121 may vary significantly, resulting in an increase in the motor's output current, an increase in the motor's output torque, or a decrease in the motor's speed.

[0137] In this embodiment, the controller 23 may also monitor at least one of the output current, output torque, or rotational speed of the motor to determine whether the firing pin 161 has begun to move upward from the firing position. For example, when the controller 23 detects that the output current of the motor, or the rate of change of the output current, is greater than a set threshold, the controller 23 may control the solenoid 191 to be de-energized, causing the stopper 194 to operate in a stopped state. Alternatively, when the controller 23 detects that the output torque of the motor or the rate of change of the torque is greater than a set threshold, the controller 23 may control the solenoid 191 to be de-energized, causing the stopper 194 to operate in a stopped state. Alternatively, when the controller 23 detects that the rotational speed or acceleration of the motor is greater than a set threshold, the controller 23 may control the solenoid 191 to be de-energized, causing the stopper 194 to operate in a stopped state.

[0138] Referring to the control circuit of the light-emitting device shown in FIG18 , some units or devices therein are consistent with those in FIG7 , and the reference numerals therein are also used. The parameter detection unit 21 may include a sensor capable of detecting the total number of nails in the clip assembly 14 or the number of nails remaining, or a sensor capable of detecting the depth of driven nails, or a sensor capable of detecting the driving force, etc. This embodiment does not specifically limit the type, installation location, or operating mode of the various sensors.

[0139] The controller 23 can obtain information transmitted by the parameter detection unit 21 and, in turn, control the light-emitting device 18 to display first information about the nails in the clip assembly 14 and / or second information about the nails that have been driven. In one embodiment, the first information may include information about the specific number of nails remaining in the clip assembly 14, information about the range of remaining nails, or an alarm message when fewer than a preset number of nails remain. The second information may include information about the driving depth of the driven nails, information about the driving force, information about the driving angle, information about the driving interval, etc.

[0140] In this embodiment, the light-emitting device 18 shown in Figures 1 and 6 includes LED digital tubes 181 and 182, or at least one light strip composed of multiple LEDs, and may also include the display screen 183 shown in Figure 6. The digital tube can display the first information and / or the second information in one or more ways such as light intensity, flash frequency, number of flashes, light color, and light quantity. The display screen 183 can directly display content data. For example, the light-emitting device 18 shown in Figure 19 can display the graphics and number of nails or the remaining number, or display the actual image or depth of the nails driven, or display a nailing animation. Not limited to digital tubes or display screens, as long as the light-emitting device can display the above information, it is within the scope of protection of this application.

[0141] In one embodiment, the controller 23 can also display the fault information of the nail gun 100 or the current working mode or battery pack information. The fault information may include various common faults, such as overtemperature, overvoltage, undervoltage, overcurrent, stall, anti-lock, etc. The working mode may include a single-shot mode and a single-drive mode, and a continuous-shot mode is a continuous-drive mode. The battery information may include the remaining power or remaining time of the battery pack, or the output voltage, or the output current, or the temperature, etc. In this embodiment, the light-emitting device 18 can also display the above-mentioned fault information or working mode or battery pack information by at least one of the following methods: light intensity, flash frequency, number of flashes, light color, light quantity, and display content data.

[0142] In one embodiment, the light-emitting device 18 can display different fault codes to indicate different fault information. For example, E1 indicates overtemperature of the power tube in the control circuit, E2 indicates motor stall, and E3 indicates battery undervoltage. By displaying faults with different fault codes, the different fault types of the nail gun are not affected by the number of light-emitting devices 18, the color of the light, or the frequency of the light, thus providing a more intelligent and simpler fault display.

[0143] In one embodiment, the display screen 183, as a light-emitting device, may also include an operating interface, such as a touch interface or an interface that can be combined with physical buttons. The operating interface can receive user operation information and transmit it to the controller 23 while displaying the operation information. The controller 23 can then control the operation of the motor 121 based on the user's operation. For example, the user can select a nailing mode or switch nailing modes on the operating interface, or set operating parameters of the nail gun, such as nailing force, nailing depth, nailing time interval, or nailing frequency.

[0144] In one embodiment, the light-emitting device 18 can be divided into a lighting device and a fault indication device. In some embodiments, the lighting device and the fault indication device can be the same device or different devices. If the lighting device and the fault indication device are the same lighting device, when the nail gun 100 is not faulty, the lighting device 18 remains constantly lit. When a fault occurs, the lighting device 18 can indicate the fault by flashing a certain frequency, color, number of flashes, or fault code, or by turning off the lighting device. If the lighting device and the fault indication device are different lighting devices, when the nail gun 100 is not faulty, the lighting device can remain constantly lit, while the fault indication device can remain permanently off. When a fault occurs, the lighting device can remain constantly lit or turn off, and the fault indication device can indicate the fault in the manner described above. If the lighting device and the fault indication device are different lighting devices, when the nail gun 100 is not faulty, the lighting device and the fault indication device can remain constantly lit. When a fault occurs, the lighting device can remain constantly lit or turn off, and the fault indication device can turn off to indicate the fault or indicate the fault in the manner described above. In one embodiment, the fault indicator device may indicate the fault level by light color and / or flashing frequency when or after indicating the fault type. For example, a green light may be permanently on when there is no fault, a yellow light may be on or flashing when there is a minor fault (such as undervoltage protection or overtemperature protection), and a red light may be on or flashing when there is a major fault (such as overcurrent protection, stall protection, or anti-lock braking protection).

[0145] In one embodiment, parameter detection unit 21 may be a brightness sensor or other sensor capable of detecting the light intensity in the nail gun's operating environment. Controller 23 may control whether light-emitting device 18 is illuminated or the light intensity thereof based on the detected light intensity. For example, when operating outdoors during daytime in good weather, light-emitting device 18 may be turned off, or at least the lighting device may be turned off. When operating indoors in dim light, the brightness of the light-emitting device may be increased, or at least the brightness of the lighting device may be enhanced.

[0146] Referring to the control circuit of the nail gun shown in FIG20 , since some structures or components of the control circuit are the same as those in FIG7 , the circuit numbers in FIG20 follow those in FIG7 . The control circuit includes at least a first control circuit 24 that can control the operation of the light-emitting device 18, and a second control circuit 25 that controls the motor 121. The first control circuit 24 can at least independently control the lighting device 18 to light up when the motor 121 is not powered on, that is, when the motor 121 is not started, the light-emitting device 18 can be controlled to light up in advance. Lighting up the light-emitting device 18 before nailing can illuminate the workpiece or working environment in advance, allowing the user to have a better user experience. Even if the motor 121 fails to start, the lighting device 18 can still work.

[0147] In one embodiment, the first control circuit 24 and the second control circuit 25 can be arranged on the same circuit board. In one embodiment, the first control circuit 24 and the second control circuit 25 can also be arranged on different circuit boards.

[0148] Referring to the nail gun control circuit shown in FIG21 , the first control circuit 24 includes at least a lighting control switch 241 and a lighting circuit 242. When the lighting control switch 241 is operated by the user, it can connect the current path between the lighting circuit 242 and the battery pack 15, thereby illuminating the lighting device 18. In this embodiment, the lighting control switch 241 can be a push button switch, a toggle switch, a membrane switch, a lever switch, a micro switch, a travel switch, etc. The second control circuit 25 is substantially the same as the control circuit in FIG7 . It controls the operation and shutdown of the motor 121 and can also be referred to as the main control circuit of the nail gun 100. In this embodiment, the second control circuit 25 includes a main switch 251, a drive circuit 22, and a controller 23. When the main switch 251 is operated by the user, it connects the current path between the controller 23, the drive circuit 22, and the motor 121. When the controller 23 outputs a control signal, the motor 121 can be controlled to operate. The implementation of how the controller 23 controls the operation of the motor 121 can be referred to in the description of the control circuit shown in FIG7 and will not be further elaborated here. It should be noted that the host switch 251 can also be a button switch, a toggle switch, a membrane switch, a lever switch, a micro switch, a travel switch, etc.

[0149] In other embodiments, the light control switch 241 may be considered not to belong to the first control circuit 24 but to be connected to the first control circuit 24. Alternatively, the host switch 251 may be considered not to belong to the second control circuit 25 but to be connected to the second control circuit 25. In other words, other methods of dividing the control circuits may be used, as long as they can achieve the corresponding functions.

[0150] In one embodiment, the nail gun 100 may include a travel switch (not shown). This travel switch functions as the aforementioned light control switch 241 when in a first travel position and as a main switch 251 when in a second travel position. In one embodiment, when the travel switch is in the second travel position, the controller 23 in the second control circuit 25 is turned on, but the motor 121 is not yet started. When the travel switch is operated to a third travel position, the motor 121 is started. In one embodiment, when the travel switch is operated to a fourth travel position, the controller 23 can perform specific control operations on the motor 121, such as controlling the motor 121 to operate at a constant speed.

[0151] In one embodiment, the light-emitting device 18 can be turned off by operating the light-emission control switch 241. Alternatively, the controller 23 in the second control circuit 25 can be used to de-energize the light-emitting circuit 242, thereby turning off the light-emitting device 18. In one embodiment, the controller 23 can also control the light-emitting circuit 242 to delay turning off, thereby delaying the extinguishing of the light-emitting device 18. It is understood that various components can be used to implement the functions of the light-emitting circuit 242, and this application does not limit the specific circuit structure of this circuit.

[0152] Continuing with FIG. 21 , the controller 23 can also control the light-emitting circuit 242 to change its circuit state based on the operating parameters of the motor 121 and / or the battery parameters of the battery pack 15 detected by the parameter detection unit 21, thereby enabling the light-emitting device 18 to change its light pattern to provide an alarm. The operating parameters of the motor 121 can include the output current, output voltage, or output power of the motor 121, the operating time of the motor 121 during a nailing cycle (i.e., the duration of the nailing cycle), the nailing frequency, the number of revolutions of the motor during a nailing cycle, or the temperature. Battery parameters can include the output voltage, current, power consumption, or temperature of the battery pack 15 during a nailing cycle. For example, if the controller 23 determines that the motor 121 is stalled based on its current, it can control the motor 121 to stop rotating and simultaneously control the light-emitting circuit 242 to change its circuit state, causing the light-emitting device 18 to flash and / or emit red light as an alarm. In this embodiment, the controller 23 can control the light emitting device 18 to issue an alarm by at least one of the following: the number of light emitting devices, the light color, the light frequency, the number of flashes, the brightness level, and the content of the light display. The controller 23 can also set an alarm based on the fault type or fault level.

[0153] Continuing with the nail gun 100 shown in Figures 1 and 2, in addition to the trigger switch 113a, it also includes a push rod switch 113b. The trigger switch 113a is configured to control the start and stop of the nail gun 100, while the push rod switch 113b can serve as a safety switch. It is located at the lower end of the firing assembly 16. When the user pushes the nail gun 100 downward in the nailing direction, i.e., in the direction of the second straight line 102, the push rod switch 113b can be pressed against the workpiece, thereby turning on the push rod switch 113b, i.e., triggering the push rod switch 113b. In this embodiment, the nail gun 100 also includes a guide assembly 114. The guide assembly 114 can be attached to the housing 11 or disposed on the housing 11 so as to partially or completely cover the firing assembly 16, thereby at least guiding the firing assembly 16 in the nailing direction. It is understood that the lower end of the guide assembly 114 can be a nail outlet. There is a height difference between the lower end of the push rod switch 113b and the lower end of the guide assembly 114. When the push rod switch 113b just contacts the workpiece, there is still a height difference between the lower end of the guide assembly 114 and the workpiece.

[0154] Generally, the nail gun 100 can have at least two operating modes: a single-drive mode and a continuous-drive mode. The single-drive mode allows for a single nail to be driven at a time, while the continuous-drive mode allows for multiple nailing operations. In one embodiment, the trigger switch 113a and the push rod switch 113b are triggered differently, corresponding to different operating modes of the nail gun 100. For example, when the push rod switch 113b is abutting a workpiece, operating the trigger switch 113a activates the single-drive mode of the nail gun 100, driving a single nail. When the trigger switch 113a is actuated and the push rod switch 113b is abutting a workpiece, the continuous-drive mode of the nail gun 100 is activated. In the continuous-drive mode, the trigger switch 113a is continuously actuated, and the user only needs to intermittently abut the push rod switch 113b against the workpiece to continuously drive nails. In other words, if the trigger switch 113a is continuously actuated, a nail is driven each time the push rod switch 113b is abutted against the workpiece. In other words, continuous nailing does not mean nailing continuously, but rather means that when the trigger switch 113a is continuously triggered, nailing is performed once each time the push rod switch 113b is turned on. Generally, when the workload is large, or the workpiece is relatively continuous or flat and needs to be fastened frequently, the user can use the continuous drive mode to continuously nail to improve work efficiency.

[0155] However, the continuous drive mode also has certain drawbacks. For example, to further increase nailing efficiency, when the trigger switch 113a is operated, the push rod switch 113b is triggered to open when it abuts the workpiece, thereby driving the nail. Typically, when the push rod switch 113b abuts the workpiece and is turned on, the lower end of the guide assembly 114 is still a certain distance from the workpiece surface, which can affect the nailing quality and effect, for example, the driven nail may be partially exposed outside the workpiece.

[0156] In order to solve this problem, in the continuous drive mode, the controller 23 can at least control the nailing timing of the nail gun 100 according to the distance from the lower end of the guide assembly 114 to the surface of the workpiece. The so-called nailing timing can be understood as an objective nailing moment with time. Or the controller 23 can control the nailing timing according to the distance between other relatively fixed positions of the nail gun 100 and the surface of the workpiece. Continuing to refer to Figure 7, the parameter detection unit 21 can be used to detect the distance from the lower end of the guide assembly 114 to the surface of the workpiece. In this embodiment, the parameter detection unit 21 can be a distance sensor, which can be set at the lower end of the guide assembly 114 (not shown), or at other fixed positions of the nail gun 100, which is not limited here. In some embodiments, the distance sensor can be a laser sensor, an ultrasonic sensor, an infrared sensor, etc.

[0157] In the continuous drive mode, when the controller 23 detects that the distance from the lower end of the guide assembly 114 to the surface of the workpiece is less than or equal to the preset distance, it can control the motor 121 to operate so that the firing assembly 16 can be released from the initial position to nail. The preset distance can be any distance greater than or equal to 0. That is, nailing is triggered when the lower end of the guide assembly 114 contacts the surface of the workpiece, or the lower end of the guide assembly 114 is very close to the surface of the workpiece. This avoids the nail being driven out when it is far away from the surface of the workpiece, affecting the nailing quality and nailing effect. When the controller 23 detects that the distance from the lower end of the guide assembly 114 to the surface of the workpiece is greater than the preset distance, at least the nailing will not be started until the monitored distance is less than or equal to the preset distance. It can also be understood that when it is detected that the distance from the lower end of the guide assembly 114 to the surface of the workpiece is greater than the preset distance, the time to start nailing is extended.

[0158] In one embodiment, not starting nailing may include reducing the starting speed. For example, the motor 121 may be controlled to reduce the rotation speed to reduce the speed of starting nailing, thereby obtaining a relatively long time for the operation push rod switch 113b to be continuously pressed down, so that the guide assembly 114 can be closer to the workpiece surface when the user continues to press the push rod switch 113b, so that the nail gun 100 can have a shorter nailing distance in the continuous drive mode.

[0159] In one embodiment, the control circuit of the nail gun 100 shown in FIG7 may include at least one filter element. For example, the power elements VT1-VT6 in the power circuit 22 may serve as the filter element, or a filter capacitor may be provided in the control circuit. This embodiment does not limit the location or type of the filter element in the control circuit; any component in the control circuit that performs a filtering function is within the scope of protection of this application. In this embodiment, deactivating nailing may also include extending the filtering time of the filter element in the control circuit, for example, by controlling the filter element to perform filtering at least twice. By extending the filtering time of the control circuit, a relatively longer period of time is achieved in which the push rod switch 113b is continuously pressed, allowing the guide assembly 114 to move closer to the workpiece surface when the user continues to press the push rod switch 113b, thereby enabling the nail gun 100 to achieve a shorter nailing distance in the continuous drive mode.

[0160] It is understood that the controller 23 may also employ other methods that require extending the time required to initiate nailing. In other words, other methods or concepts that extend the time required to initiate nailing in the continuous drive mode to reduce the distance between the guide assembly 114 and the workpiece surface to achieve better nailing quality and nailing results are within the scope of protection of this application.

[0161] Assuming that in continuous drive mode, the nailing response time is the time from when the push rod switch 113b contacts the workpiece surface to when the firing assembly 16 drives the nail. In this embodiment, the nailing response time is greater than or equal to the time from when the trigger switch 113a is operated to when the firing assembly 16 drives the nail in single drive mode. While the nailing response time is not significantly increased, better nailing results and quality are achieved.

[0162] Referring to the nail gun control process shown in FIG22 , the process includes at least the following steps:

[0163] S601, start.

[0164] S602, determine whether the nail gun is currently working in the continuous driving mode, if so, go to step S603, otherwise continue to monitor the working mode of the nail gun.

[0165] S603, detecting the distance between the lower end of the guide assembly and the surface of the workpiece.

[0166] S604, determining whether the distance is less than or equal to a preset distance, if so, executing step S605, otherwise executing step S606.

[0167] S605, controlling the motor to start nailing.

[0168] S606: Do not start nailing.

[0169] The above shows and describes the basic principles, main features and advantages of this application. Those skilled in the art should understand that the above embodiments do not limit this application in any form, and any technical solutions obtained by equivalent replacement or equivalent transformation fall within the scope of protection of this application.

Claims

1. A nail gun, comprising: case; A motor, disposed in the housing; A firing assembly is configured to move from an initial position to a firing position to drive a nail into a workpiece within a nailing cycle, and to move from the firing position to the initial position; a parameter detection unit, connected to at least the motor, and configured to detect at least the number of rotations of the motor; A controller, connected at least to the parameter detection unit; The controller is configured to: When the number of rotations is greater than or equal to a first number threshold and less than a second number threshold, the motor is controlled to operate at a constant speed.

2. The nail gun according to claim 1, wherein: The first revolution threshold is the number of revolutions of the motor when the motor drives the firing assembly to move from the initial position to the firing position; the second revolution threshold is the number of revolutions of the motor when the controller detects a stop signal.

3. The nail gun according to claim 2, wherein: The controller is configured to control the motor to brake at the constant rotation speed as the initial braking speed when the stop signal is detected.

4. The nail gun according to claim 1 further includes a power output unit; the power output unit at least includes an energy storage device that can store energy during the process of the firing assembly moving from the firing position to the initial position.

5. The nail gun according to claim 4, wherein: The parameter detection unit is further configured to detect the energy stored in the energy storage device.

6. The nail gun according to claim 5, wherein: The controller is configured to control the speed of the constant speed operation of the motor according to at least the energy stored in the energy storage device.

7. The nail gun according to claim 6, wherein: The constant speed of the motor has a positive correlation with the energy stored in the energy storage device.

8. The nail gun according to claim 4, wherein: The energy storage device is configured as a cylinder; the controller is configured to obtain the air pressure in the cylinder when the number of revolutions of the motor is greater than or equal to a first revolution threshold and less than a second revolution threshold, and set the speed of the motor at a constant speed according to the air pressure.

9. The nail gun according to claim 8, wherein: The controller is configured to calculate the kinetic energy of the cylinder according to the gas pressure in the cylinder, and set the speed of the motor to operate at a constant speed according to the kinetic energy.

10. The nail gun according to claim 1, wherein: The controller is configured to: control the motor to start in response to a start signal; during the motor start-up process, if the number of rotations is less than or equal to the minimum number of rotations when the motor is started with a stall, limit the maximum duty cycle of the start control signal to be less than or equal to a duty cycle threshold.

11. The nail gun according to claim 10, wherein: The controller is configured to set the duty cycle threshold according to at least a battery parameter of the battery pack.

12. The nail gun according to claim 11, wherein: The battery parameters of the battery pack include at least one of power, voltage, temperature, battery cells, and the number of parallel-connected battery cells.

13. The nail gun according to claim 11, wherein: The duty cycle threshold has an inverse correlation with at least one battery parameter.

14. A nail gun, comprising: case; A motor, disposed in the housing; A firing assembly is configured to move from an initial position to a firing position to drive a nail into a workpiece within a nailing cycle, and to move from the firing position to the initial position; A parameter detection unit, connected to at least the motor, and configured to detect at least a working parameter of the motor; A controller, connected at least to the parameter detection unit; The controller is configured to: When the operating parameter is greater than or equal to a first parameter threshold and less than a second parameter threshold, the motor is controlled to operate at a constant speed.

15. The nail gun according to claim 14, wherein: The working parameters of the motor include at least one of the motor's rotation speed, number of revolutions, starting current, and starting voltage.

16. The nail gun of claim 14, wherein: The first parameter threshold is the working parameter of the motor when the motor drives the firing assembly to move from the initial position to the firing position; the second parameter threshold is the working parameter of the motor when the controller detects a stop signal.

17. A nail gun comprising: case; A motor, disposed in the housing; A firing assembly is configured to move from an initial position to a firing position to drive a nail into a workpiece within a nailing cycle, and to move from the firing position to the initial position; a parameter detection unit, connected to at least the motor, and configured to detect at least the number of rotations of the motor; A controller, connected at least to the parameter detection unit; The controller is configured to: When the number of rotations is greater than or equal to a first threshold number of rotations and less than a second threshold number of rotations, the motor is controlled to drive the firing assembly at a constant rotation speed until a stop signal is detected.

18. The nail gun according to claim 17, wherein: The first revolution threshold is the number of revolutions of the motor when the motor drives the firing assembly to move from the initial position to the firing position; the second revolution threshold is the number of revolutions of the motor when the controller detects a stop signal.

19. The nail gun according to claim 17, wherein: The controller is configured to control the motor to brake at the constant rotation speed as the initial braking speed when the stop signal is detected.

20. The nail gun according to claim 17 further includes a power output unit; the power output unit includes at least an energy storage device that can store energy during the process of the firing assembly moving from the firing position to the initial position; the controller is configured to control the speed of the constant speed operation of the motor at least based on the energy stored in the energy storage device.

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