Reciprocating tool, and method for detecting occurrence of malfunction associated with position detection of reciprocating member in reciprocating tool

Abstract

The invention provides a reciprocating tool and a method for detecting the occurrence of a defect associated with position detection of a reciprocating member in the reciprocating tool. One aspect of the present invention relates to a reciprocating tool comprising a reciprocating member, a first position detector, a second position detector, and a control circuit. Control circuit based on (i) failure in receiving second position detection signal from second position detector between mth reception and (m-1) th reception of first position detection signal from first position detector, or (ii) failure in receiving second position detection signal from second position detector by control circuit The control circuit fails to receive the first position detection signal between the nth reception of the second position detection signal and the (n-1) th reception of the second position detection signal, and detects the occurrence of a defect associated with the first position detector or the second position detector. And m and n are any integer greater than or equal to 2.

Description

Technical Field

[0001] This invention relates to a reciprocating motion tool. Background Technology

[0002] Japanese Patent No. 6555423 discloses a punching machine comprising a first magnet and a second permanent magnet, and a first Hall element and a second Hall element. The first permanent magnet is disposed on a pin wheel such that when the piston of the punching machine reaches the waiting position, the first Hall element detects the magnetic field of the first permanent magnet. The pin wheel is linked to the piston. The second permanent magnet is disposed on the pin wheel such that when the piston of the punching machine reaches the adjustment position, the second Hall element detects the magnetic field of the second permanent magnet. Summary of the Invention

[0003] In the aforementioned nail-driving machine, if the first Hall element malfunctions and fails to detect the magnetic field of the first permanent magnet, the machine's controller will not stop the motor. As a result, the drive blades will not stop, potentially causing the next nail to be ejected from the machine against the user's will.

[0004] One aspect of the present invention aims to provide a technique for detecting the occurrence of malfunctions associated with the position detection of reciprocating components in a reciprocating motion tool.

[0005] In this invention, the terms "first," "second," etc., are merely intended to distinguish elements from each other, and are not intended to limit the order or number of elements. Therefore, the first element can be called the second element, and similarly, the second element can be called the first element. In addition, the first element can be present without the second element, and similarly, the second element can be present without the first element.

[0006] One aspect of the present invention provides a reciprocating motion tool comprising a reciprocating component, a first position detector, a second position detector, and a control circuit.

[0007] The reciprocating component is configured to reciprocate between the first dead point and the second dead point.

[0008] The first position detector is configured to output a first position detection signal whenever the reciprocating component reaches the first position in at least one reciprocating motion.

[0009] The second position detector (i) is different from the first position detector, and (ii) is configured to output a second position detection signal whenever the reciprocating component reaches a second position in at least one reciprocating motion. The second position is located after the first position in the at least one reciprocating motion of the reciprocating component.

[0010] The control circuit is configured to: (i) receive the first position detection signal from the first position detector; (ii) receive the second position detection signal from the second position detector; and (iii) detect the occurrence of an adverse condition associated with the first or second position detector based on (A) the control circuit failing to receive the second position detection signal between the m-th and (m-1)-th receptions of the first position detection signal, or (B) the control circuit failing to receive the first position detection signal between the n-th and (n-1)-th receptions of the second position detection signal. m and n are any integers greater than or equal to 2.

[0011] In such a reciprocating motion tool, it is possible to detect defects associated with the position detection of the reciprocating component, and more specifically, to detect the occurrence of defects associated with the first position detector or the second position detector.

[0012] Another aspect of the present invention provides a method for detecting the occurrence of a defect associated with the position detection of a reciprocating component in a reciprocating motion tool, the method comprising the steps of: causing the reciprocating component to reciprocate between a first dead point and a second dead point; receiving a first position detection signal from a first position detector in the reciprocating motion tool, the first position detector being configured to output the first position detection signal whenever the reciprocating component reaches a first position in at least one reciprocating motion; and receiving a second position detection signal from a second position detector in the reciprocating motion tool, the second position detector being configured to output the first position detection signal whenever the reciprocating component reaches its first position in at least one reciprocating motion. When the second position is reached in at least one reciprocating motion, the second position is output as a second position, which is located after the first position in the at least one reciprocating motion of the reciprocating component; and an adverse condition associated with the first position detector or the second position detector is detected based on (i) failure to receive the second position detection signal between the m-th and m-1th receptions of the first position detection signal, or (ii) failure to receive the first position detection signal between the n-th and n-1th receptions of the second position detection signal, where m and n are any integers greater than 2.

[0013] This method can detect defects associated with the position detection of the reciprocating component, and more specifically, can detect the occurrence of defects associated with the first position detector or the second position detector. Attached Figure Description

[0014] Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

[0015] Figure 1 This is an external view of the reciprocating motion tool in an exemplary embodiment.

[0016] Figure 2 This is a central longitudinal sectional view of a reciprocating motion tool.

[0017] Figure 3A yes Figure 1 A cross-sectional view of line IIIA-IIIA in the middle. Figure 3B It is a top view of a reciprocating motion tool, including a perspective view of the motor housing.

[0018] Figure 4A -4D represents a sequence of mechanical movements in a reciprocating motion tool.

[0019] Figure 5A -5E represents the movement of the support in a reciprocating motion tool, corresponding to a sequence of mechanical actions.

[0020] Figure 6 It is a circuit diagram that represents the electrical configuration of a reciprocating motion tool.

[0021] Figure 7 It is a timing diagram that represents a summary of the electrical operation of a reciprocating motion tool.

[0022] Figure 8 It is a flowchart representing the flow of the main program executed by the control circuit.

[0023] Figure 9 It is a flowchart representing the process of standby decision-making executed by the control circuit.

[0024] Figure 10 It is a flowchart representing the process of motor control execution by the control circuit.

[0025] Figure 11 It is a flowchart representing the stop process executed by the control circuit.

[0026] Figure 12 This is a flowchart representing the process of the first correction process performed by the control circuit.

[0027] Figure 13 This is a graph representing an example of a function set in the control circuit.

[0028] Figure 14 This is a flowchart representing the process of the second correction procedure performed by the control circuit.

[0029] Figure 15 This is a timing diagram illustrating an example of how an electric motor operates when an adverse condition occurs. Detailed Implementation

[0030] 1. Overview of Implementation Methods

[0031] One embodiment may provide a reciprocating motion tool having at least one of the following features:

[0032] • Feature 1: It is configured as a reciprocating component that moves back and forth between the first dead point and the second dead point;

[0033] • Feature 2: A first position detector configured to output a first position detection signal whenever the reciprocating component reaches the first position (or the first phase) in at least one reciprocating motion;

[0034] • Feature 3: (i) Unlike the first position detector, (ii) is a second position detector configured to output a second position detection signal whenever the reciprocating component reaches the second position (or the second phase) in at least one reciprocating motion;

[0035] Feature 4: The second position is located after the first position in the at least one reciprocating motion of the reciprocating component;

[0036] Feature 5: Control circuit;

[0037] Feature 6: The control circuit is configured (or programmed) to receive the first position detection signal from the first position detector;

[0038] Feature 7: The control circuit is configured (or programmed) to receive the second position detection signal from the second position detector; and

[0039] Feature 8: The control circuit is configured (or programmed) to detect a defect associated with the first position detector or the second position detector based on (i) the control circuit failing to receive the second position detection signal between the m-th and m-1-th receptions of the first position detection signal, or (ii) the control circuit failing to receive the first position detection signal between the n-th and n-1-th receptions of the second position detection signal, where m and n are any integers greater than 2.

[0040] In a reciprocating motion tool having at least features 1 to 8, it is possible to detect defects associated with the position detection of the reciprocating component, and more specifically, it is possible to detect the occurrence of defects associated with the first position detector or the second position detector.

[0041] Examples of reciprocating motion tools include: electric nailing machines, electric rebar tying machines, electric rebar cutting machines, electric oil injectors, and electric air pumps. Examples of electric oil injectors include: electric grease guns.

[0042] In one embodiment, the control circuit may also be integrated into a single electronic unit, a single electronic device, or a single circuit board.

[0043] In one embodiment, the control circuit may be a combination of two or more electronic circuits, two or more electronic units, or two or more electronic devices disposed on or within the reciprocating motion tool.

[0044] In one embodiment, the control circuit may also include: a microcomputer (or microcontroller, or microprocessor), wiring logic, an application-specific integrated circuit (ASIC), an application-specific general-purpose product (ASSP), a programmable logic device (PLD) (e.g., a field-programmable gate array (FPGA), etc.), discrete electronic components, and / or combinations thereof.

[0045] In addition to having at least one of features 1 to 8, or alternatively, a certain embodiment may also have at least one of the following features:

[0046] Feature 9: A first manual switch configured to be manually operated by the user of the reciprocating motion tool;

[0047] Feature 10: It is configured as an electric motor that generates driving force;

[0048] Feature 11: A drive circuit configured to drive the electric motor;

[0049] • Feature 12: The configuration includes a transmission device that transmits the driving force of the electric motor to the reciprocating component at least during the stroke of the reciprocating component from the second dead point to the first dead point; and

[0050] Feature 13: The control circuit is configured (or programmed) to control the drive circuit in such a way that the electric motor is driven, at least based on the manual operation of the first manual switch.

[0051] In a reciprocating motion tool having at least features 1 to 13, the user can manually operate the first manual switch to drive the reciprocating component at least from the second dead point to the first dead point.

[0052] Examples of the first manual switch include: trigger switch, push button switch, dial switch, slide switch, tactile switch, joystick, touch panel, touch screen, and graphical user interface (GUI).

[0053] Examples of electric motors include: DC motors, AC motors, and stepper motors. Examples of DC motors include: brushless DC motors and brushed DC motors.

[0054] Examples of the driving circuits include: full-bridge circuits and half-bridge circuits.

[0055] In addition to having at least one of features 1 to 13, or alternatively, a certain embodiment may also have the following features:

[0056] Feature 14: The transmission device includes a reducer (i) having a preset reduction ratio, and (ii) configured to convert the driving force of the electric motor into a reduced output and transmit it to the reciprocating component.

[0057] In a reciprocating motion tool having at least features 1 to 14, the reciprocating component can be driven from at least the second dead point to the first dead point with a torque proportional to the reduction ratio of the reducer.

[0058] Examples of the speed reducer include gear reducers. Examples of gear reducers include parallel shaft gear reducers, orthogonal shaft gear reducers, and concentric shaft gear reducers. Examples of concentric shaft gear reducers include planetary gear reducers.

[0059] In addition to having at least one of features 1 to 14, or alternatively, a certain embodiment may also have the following features:

[0060] Feature 15: The control circuit is configured (or programmed) to control the drive circuit in such a way that the drive of the electric motor is stopped based on the detection of a malfunction by the control circuit.

[0061] In a reciprocating motion tool having at least features 1 to 13, 15, it is possible to suppress the continuous driving of the electric motor when a malfunction occurs in the first position detector or the second position detector.

[0062] In addition to having at least one of features 1 to 15, or alternatively, a certain embodiment may also have the following features:

[0063] Feature 16: The control circuit is configured (or programmed) to control the drive circuit by braking the electric motor based on the detection of a malfunction by the control circuit.

[0064] In a reciprocating motion tool having at least features 1 to 13, 16, when a malfunction occurs in the first position detector or the second position detector, the rotation of the electric motor can be stopped quickly, and consequently, the movement of the reciprocating component from at least the second dead point toward the first dead point can be stopped quickly.

[0065] In addition to having at least one of features 1 to 16, or alternatively, a certain embodiment may also have at least one of the following features:

[0066] Feature 17: The electric motor has a rotor;

[0067] Feature 18: A rotational position detector configured to output a rotational position signal indicating that the rotor has rotated by a predetermined angle to the control circuit; and

[0068] Feature 19: The control circuit is configured (or programmed) to invalidate the m-th reception of the first position detection signal or the n-th reception of the second position detection signal based on (i) the failure to receive a predetermined number of rotation position signals from the rotation position detector between the m-th reception and the (m-1)-th reception of the first position detection signal, or (ii) the failure to receive a predetermined number of rotation position signals from the rotation position detector between the n-th reception and the (n-1)-th reception of the second position detection signal.

[0069] In a reciprocating motion tool having at least features 1 to 13 and 17 to 19, it is possible to suppress the false detection of an adverse condition by the control circuit when the control circuit receives electrical noise as a detection signal for the first position or the second position at a time when the electric motor fails to bring the reciprocating component to the first position or the second position.

[0070] Examples of the rotary position detector include Hall sensors and pulse encoders. Examples of the rotary position signal include pulse signals (or rectangular wave signals) and sine wave signals.

[0071] In addition to having at least one of features 1 to 19, or alternatively, a certain embodiment may also have at least one of the following features:

[0072] Feature 20: The control circuit is configured (or programmed) to control the drive circuit by outputting a pulse width modulation signal to it; and

[0073] Feature 21: The drive circuit is configured to drive the electric motor based on the pulse width modulation signal.

[0074] In a reciprocating motion tool having at least features 1 to 13, 20, and 21, the control circuit is capable of controlling the electric motor via the pulse width modulation signal.

[0075] In addition to having at least one of features 1 to 21, or alternatively, a certain embodiment may also have at least one of the following features:

[0076] • Feature 22: It is configured as a pressing component that is pressed onto the workpiece by the user;

[0077] • Feature 23: Configured as: a second manual switch that is manually operated by being pressed against the workpiece via the pressing member; and

[0078] Feature 24: The control circuit is configured (or programmed) to control the drive circuit in such a way that the electric motor is driven by manually operating both the first manual switch and the second manual switch.

[0079] In a reciprocating motion tool having at least features 1 to 13 and 22 to 24, it is possible to suppress the electric motor from being erroneously driven when the pressing member is not pressed onto the workpiece, that is, when the user is not processing the workpiece.

[0080] In addition to having at least one of features 1 to 24, or alternatively, a certain embodiment may also have at least one of the following features:

[0081] Feature 25: A cylinder (or chamber) containing compressed gas inside;

[0082] Feature 26: (i) located within the cylinder, (ii) a piston that applies force to the reciprocating component at the second dead center by the aforementioned compressed gas; and

[0083] Feature 27: The reciprocating component is configured to be driven from the first dead point to the second dead point by the piston.

[0084] In a reciprocating motion tool having at least features 1 to 13 and 25 to 27, the reciprocating component is able to move from the first dead point to the second dead point by pressure applied to the piston from the compressed gas.

[0085] Examples of compressed gases include compressed air and compressed inert gases. The compressed air may be compressed dry air. Examples of compressed inert gases include compressed nitrogen and compressed rare gases.

[0086] In addition to having at least one of features 1 to 27, or alternatively, a certain embodiment may also have at least one of the following features:

[0087] Feature 28: The first position detector includes: (i) a first magnet, and (ii) a first Hall element configured to detect the first magnetic pole of the first magnet, and configured such that, corresponding to the reciprocating component having reached the first position, the first Hall element detects the first magnetic pole of the first magnet and outputs the first position detection signal;

[0088] Feature 29: The second position detector includes: (i) a second magnet, and (ii) a second Hall element configured to detect a second magnetic pole of the second magnet, and configured such that, corresponding to the reciprocating component reaching the second position, the second Hall element detects the second magnetic pole of the second magnet and outputs the second position detection signal; and

[0089] Feature 30: The second magnetic pole has a polarity opposite to that of the first magnetic pole.

[0090] Compared to reciprocating tools configured to mechanically detect the position of the reciprocating component, reciprocating tools possessing at least features 1-8 and 28-30 exhibit superior durability. Furthermore, compared to reciprocating tools configured to optically detect the position of the reciprocating component, such reciprocating tools are less susceptible to dust interference during position detection.

[0091] In addition to having at least one of features 1 to 30, or alternatively, a certain embodiment may also have at least one of the following features:

[0092] Feature 31: The transmission device includes a cam (i) having an outer periphery having a plurality of pins arranged in the circumferential direction of the cam, and (ii) being configured to rotate by the driving force of the electric motor;

[0093] Feature 32: The transfer device comprises: (i) a support for holding the first magnet and the second magnet, and (ii) a bracket configured to rotate together with the cam; and

[0094] Feature 33: The reciprocating component (i) extends between the first stop and the second stop, (ii) has a plurality of racks in its extending direction, and (iii) is configured to be driven from the second stop toward the first stop by engaging the plurality of racks with the plurality of pins respectively.

[0095] In a reciprocating motion tool having at least features 1 to 13 and 28 to 33, the reciprocating component is capable of moving from at least the second dead point to the first dead point via the cam. Furthermore, based on the rotational position of the support that rotates together with the cam, the arrival of the reciprocating component toward the first position or the second position can be detected.

[0096] In addition to having at least one of features 1 to 33, or alternatively, a certain embodiment may also have the following features:

[0097] Feature 34: The first magnetic pole and the second magnetic pole are directed toward the radially outer side of the support.

[0098] In a reciprocating tool having at least features 1 to 13 and 28 to 34, the first Hall element and the second Hall element can be disposed radially outward of the support. As a result, the size of the reciprocating tool in the direction intersecting the radial direction of the support can be reduced.

[0099] In addition to having at least one of features 1 to 34, or alternatively, a certain embodiment may also have at least one of the following features:

[0100] Feature 35: The cam and the bracket are configured to rotate about the same axis; and

[0101] Feature 36: The electric motor has a rotor that acts as the same shaft.

[0102] In addition to having at least one of features 1 to 36, or alternatively, a certain embodiment may also have the following features:

[0103] Feature 37: The support is a non-magnetic body.

[0104] In a reciprocating motion tool having at least features 1 to 13, 28 to 33, and 37, the first Hall element or the second Hall element can easily detect the first magnetic pole or the second magnetic pole.

[0105] In addition to having at least one of features 1 to 37, or alternatively, a certain embodiment may also have the following features:

[0106] Feature 38: The reciprocating component is configured such that (i) it is located at the first dead center, corresponding to the piston being located at its top dead center, and (ii) it is located at the second dead center, corresponding to the piston being located at its bottom dead center.

[0107] In reciprocating tools having at least 1 to 13, 25 to 27, or 38 components, the maximum pressure of the compressed gas is applied to the reciprocating component, thereby enabling the reciprocating component to move from the first dead point to the second dead point. Furthermore, the reciprocating component moving from the second dead point to the first dead point can be decelerated by the pressure of the compressed gas.

[0108] In addition to having at least one of features 1 to 38, or alternatively, a certain embodiment may also have at least one of the following features:

[0109] Feature 39: The first position corresponds to the stop preparation position for preparing the reciprocating component to stop; and

[0110] Feature 40: The second position corresponds to (i) a stop position that stops the reciprocating component, and / or (ii) a waiting position that allows the reciprocating component to wait for at least one next reciprocating action.

[0111] One implementation may provide a method having at least one of the following features:

[0112] Feature 41: The reciprocating component in the reciprocating motion tool reciprocates (once, or at least twice) between the first dead point and the second dead point;

[0113] Feature 42: Receives a first position detection signal from the first position detector in the reciprocating motion tool;

[0114] Feature 43: The first position detector is configured to output the first position detection signal whenever the reciprocating component reaches the first position (or the first phase) in at least one reciprocating motion;

[0115] Feature 44: Receives a second position detection signal from the second position detector in the reciprocating motion tool;

[0116] Feature 45: The second position detector (i) is different from the first position detector, and (ii) is configured to output the second position detection signal whenever the reciprocating component reaches the second position (or the second phase) in at least one reciprocating motion;

[0117] Feature 46: The second position is located after the first position during the at least one reciprocating motion of the reciprocating component; and

[0118] Feature 47: The occurrence of an adverse condition associated with the first position detector or the second position detector is detected based on (i) the failure to receive the second position detection signal between the m-th and m-1-th receptions of the first position detection signal, or (ii) the failure to receive the first position detection signal between the n-th and n-1-th receptions of the second position detection signal, where m and n are any integers greater than 2.

[0119] The method having at least features 41 to 47 is capable of detecting defects associated with the position detection of the reciprocating component, and more specifically, is capable of detecting the occurrence of defects associated with the first position detector or the second position detector.

[0120] In one embodiment, features 1 to 47 described above may also be combinations of any combination.

[0121] In one embodiment, any one of the features 1 to 47 described above may be excluded.

[0122] 2. Specific exemplary implementation methods

[0123] The following describes specific exemplary embodiments. These specific exemplary embodiments provide... Figure 1 The reciprocating motion tool 1 shown.

[0124] The terms "up," "down," "front," "back," "left," and "right" used in the following description or accompanying drawings are merely for the purpose of making the structure of the reciprocating motion tool 1 easier to understand, and are not intended to limit the orientation of the reciprocating motion tool 1. The reciprocating motion tool 1 can be configured in all orientations.

[0125] 2-1. Overall Structure of Reciprocating Motion Tools

[0126] like Figure 1As shown, the reciprocating tool 1 in this embodiment is an electric nailing machine configured to drive nails into a workpiece. Examples of nails used in the reciprocating tool 1 include U-shaped nails, pins, concealed nails, and foot nails. In other embodiments, the reciprocating tool 1 can be any other type of reciprocating tool such as an electric rebar tying machine, an electric rebar cutter, an electric oiler, and an electric air pump.

[0127] The reciprocating tool 1 includes a housing 2. The housing 2 includes a drive assembly receiving portion 3 extending from its rear end toward its front end (i.e., in the direction of nail ejection). The reciprocating tool 1 has an ejection portion 4 in front of the drive assembly receiving portion 3. The ejection portion 4 includes a guide portion 5 configured to guide the nail ejected from the reciprocating tool 1 toward a workpiece. In this embodiment, the guide portion 5 protrudes from the interior of the drive assembly receiving portion 3 toward the front of the reciprocating tool 1. The ejection portion 4 includes a crimping member (or contactor) 6 configured to be crimped onto the workpiece. The crimping member 6 is positioned above the guide portion 5 and protrudes forward in the reciprocating tool 1. The ejection portion 4 includes a connecting mechanism 7 connected to the crimping member 6.

[0128] The outer casing 2 includes a gripping portion 8 extending downward from approximately the center of the insertion component receiving portion 3. The gripping portion 8 is configured to be held by the user of the reciprocating motion tool 1 with one hand. The gripping portion 8 has a trigger 9 on its upper front side. The trigger 9 is configured to be pulled by the user's finger (e.g., index finger).

[0129] The housing 2 includes a motor housing 10 extending downward from the front of the component receiving portion 3. The housing 2 also includes a battery mounting portion 11 extending from the lower end of the motor housing 10 toward the lower end of the grip portion 8. The battery mounting portion 11 is configured such that the battery pack 12 can be detachably mounted to the battery mounting portion 11.

[0130] The reciprocating tool 1 has a nail box 13 on the left side of the housing 2, extending from the lower part of the guide portion 5 to the lowermost end of the reciprocating tool 1. The nail box 13 is configured to feed one or more nails housed therein into the guide portion 5 one by one. In this embodiment, the nail box 13 is tilted rearward.

[0131] like Figure 2 As shown, the drive assembly receiving section 3 receives the drive assembly 14, which is configured to drive in a nail.

[0132] The injection assembly 14 includes a cylinder 15 extending from the rear end of the injection assembly housing 3 toward approximately the center. The cylinder 15 contains compressed gas. In this embodiment, the compressed gas is compressed, dried air. In other embodiments, the compressed gas may be compressed nitrogen or other compressed inert gases such as rare gases.

[0133] The cylinder 15 has a piston 16 inside. The piston 16 is configured to move between the rear end and the front end of the cylinder 15 while sealing the cylinder 15. The injection assembly 14 has a buffer 17 at the front end of the cylinder 15. The buffer 17 is configured to receive the piston 16 that has reached the front end of the cylinder 15 and stop the piston 16.

[0134] The injection assembly 14 includes a reciprocating member (or driver) 18 connected to the piston 16 via a buffer 17. The reciprocating member 18 extends from the piston 16 toward the front end of the guide portion 5. The reciprocating member 18 is configured to move toward the front end of the guide portion 5 by pressure applied to the piston 16 from compressed gas. In other words, the piston 16 exerts force on the reciprocating member 18 toward the front end of the guide portion 5 by compressed gas. In this embodiment, the reciprocating member 18 has a length such that (i) the front end of the reciprocating member 18 reaches the front end of the cylinder 15 (i.e., the bottom dead center of the piston 16), and (ii) the front end of the reciprocating member 18 retracts into the injection assembly receiving portion 3 when the piston 16 reaches the rear end of the cylinder 15 (i.e., the top dead center of the piston 16).

[0135] The linking mechanism 7 of the injection section 4 has a spring 19 inside the injection component receiving section 3. The linking mechanism 7 is configured such that it applies force to the pressing member 6 in the forward direction by means of the spring 19, and on the other hand, corresponding to the front end of the pressing member 6 being pressed to the workpiece, it causes the pressing member 6 to move in the rear direction of the reciprocating motion tool 1.

[0136] The insertion component receiving section 3 houses the contactor switch 20 above the reciprocating component 18. The contactor switch 20 is configured such that when the crimping component 6 is pressed against the workpiece, it is pushed (i.e. turned on) by the linking mechanism 7.

[0137] The gripping part 8 houses the trigger switch 21. The trigger switch 21 is configured to be pushed (i.e., turned on) when the trigger 9 is pulled. The trigger switch 21 is configured to be turned off when the user's finger is removed from the trigger 9.

[0138] The battery assembly 11 houses the connector 22, which is configured to be detachably connected to the battery pack 12 assembled in the battery assembly 11. The battery assembly 11 houses the controller 23 above the connector 22.

[0139] The motor housing 10 houses the electric motor 24 at its lower part. In this embodiment, the electric motor 24 is a 3-phase brushless DC motor. In other embodiments, the electric motor 24 may be: a single-phase brushless DC motor, a 2-phase brushless DC motor, a 4-phase or higher brushless DC motor, a brushed DC motor, an AC motor, or a stepper motor.

[0140] The motor housing 10 houses the transmission device 25 above the electric motor 24. The transmission device 25 is connected to the rotor 26 of the electric motor 24 and is configured to transmit the driving force of the electric motor 24 to the reciprocating component 18.

[0141] More specifically, the transmission device 25 includes a reducer 27, which (i) has a preset reduction ratio and (ii) is configured to convert the driving force of the electric motor 24 into a reduced output and transmit it to the reciprocating member 18. Therefore, the transmission device 25 can transmit torque proportional to the reduction ratio of the reducer 27 to the reciprocating member 18. In this embodiment, the reducer 27 is a concentric shaft gear reducer, more specifically, a planetary gear reducer. In other embodiments, the reducer 27 may be a parallel shaft gear reducer or an orthogonal shaft gear reducer, depending on the structure of the transmission device 25.

[0142] like Figure 3A As shown, the transmission device 25 has a cam 28 above the reducer 27. In this embodiment, the cam 28 is in the shape of a circular plate. The cam 28 has pins 29a to 29i 1 to 9 along its circumferential direction on its outer periphery. The cam 28 is configured to rotate in response to the output of the reducer 27. More specifically, when viewed from above the reciprocating tool 1, the cam 28 rotates counterclockwise around the rotor 26 of the electric motor 24.

[0143] The reciprocating component 18 has racks 30a to 30i from the first to the ninth position on its right side. The racks 30a to 30i are arranged in a row along the extending direction of the reciprocating component 18. The racks 30a to 30i correspond to pins 29a to 29i from the first to the ninth position, respectively. The pins 29a to 29i engage with the racks 30a to 30i, thereby transmitting the driving force of the electric motor 24 to the reciprocating component 18.

[0144] like Figure 3BAs shown, the transmission device 25 has a support 31 above the cam 28. In this embodiment, the support 31 is circular. The support 31 is a non-magnetic body. The support 31 has a first magnet 32 ​​on its upper surface. In this embodiment, the first magnet 32 ​​is arranged on the upper surface of the support 31 with its S pole facing radially outward. In other embodiments, the first magnet 32 ​​may be arranged on the upper surface of the support 31 with its N pole facing radially outward.

[0145] The support 31 has a second magnet 33 on its upper surface. In this embodiment, the second magnet 33 is disposed on the upper surface of the support 31 with its N pole facing radially outward. In other embodiments, the second magnet 33 may be disposed on the upper surface of the support 31 with its S pole facing radially outward.

[0146] The bracket 31 is configured to rotate by receiving the output of the reducer 27. More specifically, when viewed from above the reciprocating tool 1, the bracket 31, together with the cam 28, rotates counterclockwise around the rotor 26 of the electric motor 24.

[0147] The motor housing 10 has a Hall IC 34 on its right inner wall. The Hall IC 34 is opposite to the outer periphery of the bracket 31. The Hall IC 34 is configured to: (i) detect the S pole of the first magnet 32 ​​when the first magnet 32 ​​approaches the Hall IC 34, and (ii) detect the N pole of the second magnet 33 when the second magnet 33 approaches the Hall IC 34.

[0148] The outer casing 2 has a main power switch 36 on its upper rear left side, configured to be pushed by the user to turn the power of the reciprocating motion tool 1 on or off.

[0149] The housing 2 includes a mode selection switch 37 adjacent to the main power switch 36. The mode selection switch 37 is configured such that the user can push and press it to select the operating mode of the reciprocating motion tool 1.

[0150] The housing 2 has a first display 38 between the main power switch 36 and the mode selection switch 37. The first display 38 is lit (i) when the reciprocating motion tool 1 is set to the single-shot mode described later, or (ii) when the reciprocating motion tool 1 malfunctions.

[0151] The housing 2 includes a second display 39 adjacent to the first display 38. The second display 39 is illuminated (i) when the reciprocating motion tool 1 is set to the continuous firing mode described later, or (ii) when the reciprocating motion tool 1 malfunctions.

[0152] 2-2. Mechanical motion of reciprocating motion tools

[0153] 2-2-1. Mechanical movement of reciprocating components and cams

[0154] Reference Figures 4A to 4D This explains the operation of the reciprocating component 18 and the cam 28. In most cases, when processing a workpiece, the user uses the reciprocating tool 1 with its front end facing downwards. Therefore, in... Figures 4A to 4D In the middle, the front end of the reciprocating motion tool 1 faces downward.

[0155] like Figure 4A As shown, the reciprocating component 18 is typically held in a waiting position. This waiting position is set near the top dead center of the reciprocating component 18. In this embodiment, the waiting position is a position where the reciprocating component 18 stops, and also a position where the reciprocating component 18 waits for its next reciprocating motion. In the waiting position, the first to eighth pins 29a to 29h of the cam 28 disengage from the first to eighth racks 30a to 30h of the reciprocating component 18, and only the ninth pin 29i of the cam 28 engages with the ninth rack 30i of the reciprocating component 18. At this time, the piston 16 is near its top dead center.

[0156] When the electric motor 24 is driven, causing the cam 28 to rotate counterclockwise, as Figure 4B As shown, the reciprocating component 18 is driven from the waiting position toward its top dead center. At this time, the piston 16 also reaches its top dead center.

[0157] When the reciprocating component 18 reaches its top dead center, causing the 9th pin 29i to disengage from the 9th rack 30i, as Figure 4C As shown, the reciprocating component 18 is driven to its lower dead center by the pressure of the compressed gas applied from the piston 16. As a result, the nail supplied to the guide 5 is struck by the reciprocating component 18 and driven into the workpiece. When the reciprocating component 18 reaches its lower dead center, the piston 16 also reaches its lower dead center. The cam 28 continues to rotate after the 9th pin 29i disengages from the 9th rack 30i, and the 1st to 9th pins 29a to 29i re-engage with the 1st to 9th racks 30a to 30i respectively. Moreover, as Figure 4D As shown, the reciprocating component 18 returns to the waiting position, and the cam 28 is stopped.

[0158] 2-2-2. Mechanical movement of the stent

[0159] When the electric motor 24 is driven, the bracket 31 and the cam 28 move together as... Figures 5A-5E Rotate as shown. Figures 5A-5C 5E and Figures 4A-4D Correspondingly. Figure 5DIndicates: Cam 28 is in position (i) Figure 4C The rotational position of the cam 28 shown is related to (ii). Figure 4D The rotational position of the bracket 31 between the rotational positions of the cam 28 shown.

[0160] The Hall IC 34 includes a first Hall element 34a. In this embodiment, the first Hall element 34a is configured to detect the S pole of the first magnet 32. In other embodiments, when the first magnet 32 ​​is disposed on the upper surface of the support 31 with its N pole facing radially outward from the support 31, the first Hall element 34a may be configured to detect the N pole of the first magnet 32.

[0161] The Hall IC 34 includes a second Hall element 34b. In this embodiment, the second Hall element 34b is configured to detect the N pole of the second magnet 33. In other embodiments, when the second magnet 33 is disposed on the upper surface of the support 31 with its S pole facing radially outward from the support 31, the second Hall element 34b may be configured to detect the S pole of the second magnet 33.

[0162] The first magnet 32 ​​is in the rotation direction of the bracket 31 ( Figures 5A-5E It is positioned in front of the second magnet 33 (rotating counterclockwise).

[0163] To be more specific, such as Figure 5D As shown, the first magnet 32 ​​is positioned on the upper surface of the bracket 31 such that its S pole is opposite to the first Hall element 34a at the moment when it begins to prepare to stop the cam 28.

[0164] like Figure 5A As shown in 5E, the second magnet 33 is arranged on the upper surface of the bracket 31 such that its N pole is opposite to the second Hall element 34b when the reciprocating component 18 is in the waiting position.

[0165] 2-3. Electrical Configuration of Reciprocating Motion Tools

[0166] like Figure 6As shown, the electric motor 24 includes first to third coils 24a to 24c, which are respectively associated with the three phases (i.e., U-phase, V-phase, and W-phase) of the electric motor 24. The first to third coils 24a to 24c are configured to be energized sequentially to generate a rotating magnetic field. In this embodiment, the first to third coils 24a to 24c are connected in a delta configuration. In other embodiments, the first to third coils 24a to 24c may be connected in a star configuration (or a Y configuration). The rotor 26 (i) includes a first pole 26a and a second pole 26b, and (ii) is configured to rotate by receiving the rotating magnetic field generated by the first to third coils 24a to 24c through the first pole 26a and the second pole 26b.

[0167] The electric motor 24 includes a rotational position detector 24d. The rotational position detector 24d is configured to output first to third pulse signals (or rectangular wave signals) to the controller 23 corresponding to the rotational position of the rotor 26. In this embodiment, the rotational position detector 24d is a Hall sensor. In this embodiment, the first to third pulse signals reverse from positive (or HIGH) to negative (or LOW) or vice versa whenever the rotor 26 rotates by an electrical angle of 180 degrees. The first to third pulse signals have a phase difference of 60 degrees between them. In other embodiments, the rotational position detector 24d may be configured to output one pulse signal to the controller 23 each time the rotor 26 rotates by an electrical angle of 60 degrees, instead of the first to third pulse signals. Furthermore, in other embodiments, the rotational position detector 24d may be configured to output first to third sine wave signals to the controller 23, instead of the first to third pulse signals. In this case, the controller 23 may include a waveform conversion circuit configured to convert the first to third sine wave signals into first to third pulse signals. Furthermore, in other embodiments, the rotary position detector 24d may be a pulse encoder.

[0168] The reciprocating tool 1 includes a power line Lp extending from the positive terminal of the battery pack 12 mounted in the battery assembly 11 to the controller 23. The reciprocating tool 1 also includes a grounding wire Ln extending from the negative terminal of the battery pack 12 mounted in the battery assembly 11 to the controller 23. The grounding wire Ln is connected to the grounding terminal of the reciprocating tool 1 on the controller 23. The battery pack 12 applies its output voltage (hereinafter referred to as battery voltage) between the power line Lp and the grounding wire Ln.

[0169] The controller 23 includes a control circuit 51. In this embodiment, the control circuit 51 includes a microcomputer 51a. The microcomputer 51a includes a CPU (not shown), a ROM (not shown), a RAM (not shown), an analog-to-digital (A-D) converter (not shown), an input port (not shown), and an output port (not shown). In other embodiments, the control circuit 51 may include an additional microcomputer. Furthermore, in other embodiments, the control circuit 51 may include, in addition to the microcomputer 51a, or instead of it, a logic circuit (or wiring logic connection) including two or more electronic components. Furthermore, in other embodiments, the control circuit 51 may include, in addition to the microcomputer 51a, or instead of it, an ASIC and / or an ASSP. Furthermore, in other embodiments, the control circuit 51 may include, in addition to the microcomputer 51a, or instead of it, a PLD capable of constructing reconfigurable logic circuits. Examples of PLDs include FPGAs.

[0170] The control circuit 51 is connected to the rotary position detector 24d. The control circuit 51 is configured to: (i) receive the first to third pulse signals from the rotary position detector 24d, and (ii) identify the rotational position of the rotor 26 based on the received first to third pulse signals.

[0171] The control circuit 51 is connected to the main power switch 36. The main power switch 36 includes: (i) a first contact connected to the ground terminal of the reciprocating tool 1, and (ii) a second contact connected to the control circuit 51. Therefore, the main power switch 36 is configured to output a first negative logic signal to the control circuit 51 in response to the main power switch 36 being pushed (i.e., turned on). The control circuit 51 is configured to recognize that the main power switch 36 has been turned on based on the first negative logic signal received by the control circuit 51 from the main power switch 36.

[0172] Control circuit 51 is connected to mode selection switch 37. Mode selection switch 37 includes: (i) a first contact connected to the ground terminal of reciprocating tool 1, and (ii) a second contact connected to control circuit 51. Therefore, mode selection switch 37 is configured to output a second negative logic signal to control circuit 51 in response to mode selection switch 37 being pushed (i.e., turned on). Control circuit 51 is configured to recognize that mode selection switch 37 has been turned on based on receiving the second negative logic signal from mode selection switch 37.

[0173] Control circuit 51 is connected to contactor switch 20. Contactor switch 20 includes: (i) a first contact connected to the ground terminal of reciprocating tool 1, and (ii) a second contact connected to control circuit 51. Therefore, contactor switch 20 is configured to output a third negative logic signal to control circuit 51 in response to being pressed against the workpiece by crimping member 6 (i.e., being turned on). Control circuit 51 is configured to recognize that contactor switch 20 has been turned on based on the third negative logic signal received from contactor switch 20.

[0174] The control circuit 51 is connected to the first Hall element 34a. The first Hall element 34a is configured to output a first position detection signal to the control circuit 51 in accordance with the detection of the S pole of the first magnet 32 ​​by the first Hall element 34a. In this embodiment, the first position detection signal is a negative logic signal. In other embodiments, the first position detection signal can be a positive logic signal.

[0175] The control circuit 51 is connected to the second Hall element 34b. The second Hall element 34b is configured to output a second position detection signal to the control circuit 51 in accordance with the detection of the N pole of the second magnet 33 by the second Hall element 34b. In this embodiment, the second position detection signal is a negative logic signal. In other embodiments, the second position detection signal can be a positive logic signal.

[0176] The control circuit 51 is configured to (i) be connected to the first display 38, and (ii) output a first lighting signal to the first display 38. The first display 38 is configured to receive the first lighting signal from the control circuit 51 and then light up.

[0177] The control circuit 51 is configured to (i) be connected to the second display 39, and (ii) output the second lighting signal to the second display 39. The second display 39 is configured to receive the second lighting signal from the control circuit 51 and then light up.

[0178] The controller 23 includes a power supply circuit 52 connected to: (i) the first contact of the main power switch 36, (ii) the control circuit 51, (iii) the power line Lp, and (iv) a ground terminal. The main power switch 36 is configured to output a first negative logic signal to the power supply circuit 52, in addition to the control circuit 51. The control circuit 51 is configured to output a remote control (RC) signal to the power supply circuit 52. In this embodiment, the RC signal is a negative logic signal. In other embodiments, the RC signal can be a positive logic signal.

[0179] The power supply circuit 52 is configured to maintain its on state during either (i) when receiving a first negative logic signal from the main power switch 36, or (ii) when receiving an RC signal from the control circuit 51. In its on state, the power supply circuit 52 generates a fixed DC voltage (hereinafter referred to as the power supply voltage) Vc based on the battery voltage. The power supply voltage Vc generated by the power supply circuit 52 is supplied via a path not shown to various circuits on the rotary position detector 24d, the first Hall element 34a, the second Hall element 34b, the first display 38, the second display 39, and the controller 23.

[0180] The controller 23 includes a voltage measurement circuit 53, which is configured to: (i) measure the battery voltage on the power line Lp, and (ii) output a battery voltage signal to the control circuit 51. The battery voltage signal is an analog signal having a voltage corresponding to the measured battery voltage.

[0181] The controller 23 includes a first latch circuit 54 connected to: (i) the first contact of the contactor switch 20 and (ii) the second Hall element 34b. The first latch circuit 54 is configured to: (i) maintain its output (POS) in negative (or LOW) corresponding to the falling edge of the second position detection signal output from the second Hall element 34b, and (ii) reset its output to positive (or HIGH) corresponding to the third negative logic signal output from the contactor switch 20.

[0182] The controller 23 includes a drive circuit 55 connected to the control circuit 51. The control circuit 51 is configured to output pulse width modulation (PWM) signals from the first to the sixth pulse width modulation (PWM) signals to the drive circuit 55. The first to the sixth PWM signals share the same cycle. The drive circuit 55 is configured to drive the electric motor 24 according to the first to the sixth PWM signals received from the control circuit 51.

[0183] More specifically, the drive circuit 55 includes a signal amplifier (or level converter) 55a, which is configured to amplify the first to sixth PWM signals received from the control circuit 51.

[0184] The drive circuit 55 includes: switches Q1 to Q6 forming a 3-phase full-bridge circuit. Switches Q1 to Q3 are connected to (i) the power line Lp and (ii) coils 24a to 24c, respectively, in a manner that functions as high-side switches of the 3-phase full-bridge circuit. Switches Q4 to Q6 are connected to (i) coils 24a to 24c and (ii) the ground terminal, respectively, in a manner that functions as low-side switches of the 3-phase full-bridge circuit.

[0185] Switches Q1 to Q6 are configured to receive the PWM signals amplified by signal amplifier 55a, respectively, and transition to their respective on or off states. In this embodiment, switches Q1 to Q6 are n-channel metal-oxide-semiconductor field-effect transistors (MOSFETs). In other embodiments, at least one of switches Q1 to Q6 may be a semiconductor switch of other types, including junction field-effect transistors (JFETs), bipolar transistors, and insulated-gate bipolar transistors (IGBTs). Furthermore, in other embodiments, each or at least one of switches Q1 to Q6 may be a mechanical relay.

[0186] The controller 23 includes a first signal cutoff circuit 56 configured to cut off the first to third PWM signals output from the control circuit 51. More specifically, the first signal cutoff circuit 56 is configured to: (i) be disabled (disabled) when the output (POS) of the first latch circuit 54 is positive, and (ii) be enabled (enabled) when the output of the first latch circuit 54 is negative. When the first signal cutoff circuit 56 is disabled, the first to third PWM signals are transmitted to the drive circuit 55 via the first signal cutoff circuit 56. When the first signal cutoff circuit 56 is enabled, the first to third PWM signals are cut off from the drive circuit 55 via the first signal cutoff circuit 56.

[0187] In this embodiment, the first signal cutoff circuit 56 includes wiring logic. More specifically, the first signal cutoff circuit 56 includes first to third AND gates 56a to 56c. The first to third AND gates 56a to 56c are configured to: (i) transmit the first to third PWM signals to the drive circuit 55 during the period when the output of the first latch circuit 54 is positive; and (ii) cut off the first to third PWM signals to the drive circuit 55 by setting their respective outputs to negative (or LOW) during the period when the output of the first latch circuit 54 is negative.

[0188] The controller 23 includes a current measuring circuit 57, which is configured to: (i) connect the drive circuit 55 to the ground terminal, and (ii) measure the magnitude of the current flowing through the electric motor 24 (hereinafter referred to as the motor current). The current measuring circuit 57 includes a shunt resistor R1. The shunt resistor R1 includes: (i) a first terminal connected to the fourth to sixth switches Q4 to Q6, and (ii) a second terminal connected to the ground terminal.

[0189] The current measuring circuit 57 includes a differential amplifier OP1, which is configured to: (i) measure the magnitude of the motor current flowing through the shunt resistor R1, and (ii) output a current measuring signal. More specifically, the differential amplifier OP1 is configured to amplify the voltage across the shunt resistor R1 to generate the current measuring signal. Therefore, the current measuring signal is an analog signal having a voltage corresponding to the magnitude of the motor current. The differential amplifier OP1 can be either an open-loop configuration without a negative feedback circuit from its output to its input, or a closed-loop configuration with such a negative feedback circuit. The control circuit 51 is configured to receive the current measuring signal.

[0190] The current measuring circuit 57 includes a comparator CP1, which is configured to detect when the trigger switch 21 is turned on. More specifically, the comparator CP1 is configured to: (i) compare the voltage of the current measuring signal with a preset reference voltage Vref; (ii) set its output to positive (or HIGH) when the voltage of the current measuring signal is greater than the reference voltage Vref; and (iii) set its output to negative (or LOW) when the voltage of the current measuring signal is less than or equal to the reference voltage Vref. The reference voltage Vref is equal to or approximately equal to the voltage of the current measuring signal when insufficient motor current flows through the electric motor 24, as described later.

[0191] The controller 23 includes a second latch circuit 58, which is configured to maintain the output (CUR) of the comparator CP1 in a positive (or HIGH) state corresponding to the output of the comparator CP1 being positive. The second latch circuit 58 is configured to maintain the output of the comparator CP1 in a positive state for at least a time equal to or longer than the period of the first to sixth PWM signals (e.g., 100 milliseconds) whenever the output of the comparator CP1 transitions from negative to positive. The control circuit 51 is configured to receive the output of the second latch circuit 58.

[0192] The trigger switch 21 connects (i) the power line Lp to (ii) the first to third switches Q1 to Q3. More specifically, the trigger switch 21 includes (i) a first contact connected to the power line Lp and (ii) a second contact connected to the first to third switches Q1 to Q3, and is configured to either connect or disconnect the power line Lp from the first to third switches Q1 to Q3.

[0193] The controller 23 includes a seventh switch Q7 connected to (i) the first contact and (ii) the second contact of the trigger switch 21. The seventh switch Q7 is configured such that (i) in its on state, it connects the first and second contacts of the trigger switch 21, and (ii) in its off state, it disconnects the first and second contacts of the trigger switch 21. Therefore, the seventh switch Q7 is configured such that (i) while the trigger switch 21 is in its off state and the seventh switch Q7 is in its on state, the power line Lp is connected to the first to third switches Q1 to Q3 via the seventh switch Q7, and (ii) while the trigger switch 21 is in its off state and the seventh switch Q7 is also in its off state, the power line Lp is disconnected from the first to third switches Q1 to Q3. In this embodiment, the seventh switch Q7 is an n-channel MOSFET. In other embodiments, the seventh switch Q7 can be other types of semiconductor switches, including JFETs, bipolar transistors, IGBTs, and solid-state relays (SSRs). Furthermore, in other embodiments, the seventh switch Q7 can be a mechanical relay.

[0194] The control circuit 51 is configured to output (i) a switch-on signal to turn on the 7th switch Q7 and (ii) a switch-off signal to turn off the 7th switch Q7. In this embodiment, the switch-on signal is a positive logic signal and the switch-off signal is a negative logic signal. In other embodiments, the switch-on signal can be a negative logic signal and the switch-off signal can be a positive logic signal.

[0195] The controller 23 includes a second signal cutoff circuit 59, which is configured to cut off the switch-on signal output from the control circuit 51. More specifically, the second signal cutoff circuit 59 is configured to: (i) be disabled (disabled) when the output (CUR) of the second latch circuit 58 is positive, and (ii) be enabled (enabled) when the output of the second latch circuit 58 is negative. When the second signal cutoff circuit 59 is disabled, the switch-on signal is transmitted to the seventh switch Q7 via the second signal cutoff circuit 59. When the second signal cutoff circuit 59 is enabled, the switch-on signal is cut off for the seventh switch Q7 via the second signal cutoff circuit 59.

[0196] In this embodiment, the second signal cutoff circuit 59 includes wiring logic. More specifically, the second signal cutoff circuit 59 includes a fourth AND gate 59a. The fourth AND gate 59a is configured to: (i) transmit a switch-on signal to the seventh switch Q7 during the period when the output of the second latch circuit 58 is positive, and (ii) cut off the switch-on signal for the seventh switch Q7 by setting the output of the fourth AND gate 59a to negative (or LOW) during the period when the output of the second latch circuit 58 is negative.

[0197] The controller 23 includes an electrolytic capacitor C1 configured to supply a stable motor current to the electric motor 24. The electrolytic capacitor C1 includes: (i) an anode connected to the first contact of the trigger switch 21, and (ii) a cathode connected to ground. In other embodiments, the electrolytic capacitor C1 may be removed.

[0198] 2-4. Electrical Actions of Reciprocating Motion Tools

[0199] The electrical configuration described above operates as follows.

[0200] like Figure 7 As shown, when the power circuit 52 is on, once the pressing member 6 is pressed against the workpiece, causing the contactor switch 20 to turn on, the output (POS) of the first latching circuit 54 will be held positive (or HIGH), and the first signal cutoff circuit 56 will be deactivated. The control circuit 51 identifies the rotational position of the rotor 26 based on the first to third pulse signals received from the rotational position detector 24d up to this point. The control circuit 51 selects one of (i) high-side switches and one of (ii) low-side switches according to the first table stored in the ROM, and outputs the PWM signal corresponding to these selected switches. The first table determines the combination of high-side switches and low-side switches that should be selected in association with the rotational position of the rotor 26. The first table is set to select the combination of high-side switches and low-side switches that would cause the rotor 26 to fail to rotate. More specifically, in this embodiment, the first table is set to select the following combination: (i) a combination of a high-side switch and a low-side switch that generates a magnetic field that pulls the first pole 26a toward the coil (any one of the first to third coils 24a to 24c) opposite to the first pole 26a of the rotor 26, or (ii) a combination of a high-side switch and a low-side switch that generates a magnetic field that pulls the second pole 26b toward the coil (any one of the first to third coils 24a to 24c) opposite to the second pole 26b of the rotor 26.

[0201] The corresponding PWM signals each have an initial duty cycle. The initial duty cycle is a duty cycle greater than zero but insufficient to start the electric motor 24 (e.g., 10%). With this initial duty cycle, the selected high-side switch and the selected low-side switch supply the insufficient motor current to one of the corresponding coils 24a to 24c from the first to the third coils. The rotor 26 is configured such that it does not rotate due to the insufficient motor current.

[0202] When trigger switch 21 is turned on and insufficient motor current flows, the output (CUR) of the second latch circuit 58 is kept positive (or HIGH), and the second signal cutoff circuit 59 is disabled. Once the control circuit 51 recognizes that trigger switch 21 has been turned on based on the positive output of the second latch circuit 58, a switch-on signal is transmitted from the control circuit 51 to the seventh switch Q7, and the seventh switch Q7 is then turned on. Furthermore, the control circuit 51 performs a soft start. During the soft start, the control circuit 51 selects (i) one of the high-side switches and (ii) one of the low-side switches according to a second table stored in the ROM, and outputs the PWM signal corresponding to these selected switches. The second table determines the combination of high-side and low-side switches to be selected in association with the rotational position of the rotor 26. The second table is set to select a combination of high-side and low-side switches that facilitates the rotation of the rotor 26. During the soft start, the control circuit 51 gradually increases the duty cycle of the corresponding PWM signals.

[0203] When the soft start is complete, the control circuit 51 sets the duty cycle of the PWM signal corresponding to the selected high-side switch and the selected low-side switch to 100%.

[0204] When the first Hall element 34a detects that the reciprocating component 18 has reached the stop preparation position, the control circuit 51 begins to prepare to stop the electric motor 24. Specifically, the control circuit 51 calculates the remaining drive time of the electric motor 24. When the calculated remaining drive time has elapsed, the control circuit 51 sets the duty cycle of all PWM signals from the first to the sixth to 0%, causing the electric motor 24 to transition to a free-running state.

[0205] Next, when the second Hall element 34b detects that the reciprocating component 18 has reached the waiting position, (i) the output (POS) of the first latch circuit 54 is reset to negative (or LOW), (ii) the first signal cutoff circuit 56 is activated, and (iii) the first to third PWM signals are cut off for the first to third switches Q1 to Q3 via the first signal cutoff circuit 56. Almost simultaneously, the control circuit 51 outputs a PWM signal with a specified duty cycle (e.g., 100%) to at least two of the fourth to sixth switches Q4 to Q6 to cause the electric motor 24 to undergo short-circuit braking (or regenerative braking). Accordingly, the electric motor 24 stops when short-circuit braking occurs.

[0206] When the control circuit 51 detects that the electric motor 24 has stopped based on the first to third pulse signals, it transmits a switch-off signal from the control circuit 51 to the seventh switch Q7, thereby turning off the seventh switch Q7.

[0207] 2-5. Movement patterns of reciprocating motion tools

[0208] As described above, the reciprocating motion tool 1 is configured to switch between single-shot mode and burst-fire mode. The general outline of the operation of the reciprocating motion tool 1 in single-shot mode and burst-fire mode is as follows.

[0209] In single-shot mode, when the trigger 9 is pulled while the crimping component 6 is being crimped onto the workpiece, the reciprocating tool 1 will drive a nail into the workpiece.

[0210] In single-shot mode, when the pressing component 6 is pressed onto the workpiece while the trigger 9 is pulled, the reciprocating motion tool 1 does not drive the nail in.

[0211] In continuous firing mode, with trigger 9 already pulled, whenever crimping component 6 is crimped onto the workpiece, reciprocating tool 1 will drive a nail into the workpiece.

[0212] 2-6. Processing performed by the control circuit

[0213] The following describes in detail the processing performed by the control circuit 51 (more specifically, the microcomputer 51a).

[0214] 2-6-1. Main Program

[0215] The control circuit 51 repeatedly executes its operation. Figure 8 The main program shown.

[0216] like Figure 8 As shown, the control circuit 51 first waits in S110 until a preset time base is reached (S110: NO). When the time base is reached (S110: YES), the control circuit 51 sequentially transitions from S120 to S170.

[0217] In S120, the control circuit 51 performs A-D conversion processing. In the A-D conversion processing, the control circuit 51 converts the battery voltage signal and the current measurement signal into their respective digital values ​​and stores the respective digital values ​​in RAM.

[0218] In S130, the control circuit 51 performs a switch determination process. In the switch determination process, the control circuit 51 stores the logic (positive or negative, or HIGH or LOW, or 1 or 0) of the voltages received from the main power switch 36, the mode selection switch 37, the contactor switch 20, the first Hall element 34a, the second Hall element 34b, and the second latch circuit 58 in RAM.

[0219] In S140, control circuit 51 performs a standby decision process. Details of the standby decision process will be described later.

[0220] In S150, the control circuit 51 performs a defect condition determination process. During this process, the control circuit 51 determines whether an error flag is set. The error flag is (i) set when a defect occurs, and (ii) cleared when no defect occurs. If an error flag is set, the control circuit 51 performs a pre-determined action corresponding to the defect.

[0221] In S160, control circuit 51 performs motor control processing. Details of the motor control processing will be described later.

[0222] In S170, the control circuit 51 performs display processing. During display processing, the control circuit 51 illuminates either the first display 38 or the second display 39 corresponding to the set operating mode. More specifically, when the reciprocating motion tool 1 is set to single-fire mode, the control circuit 51 outputs a first illumination signal to the first display 38. When the reciprocating motion tool 1 is set to continuous-fire mode, the control circuit 51 outputs a second illumination signal to the second display 39. Furthermore, when an error flag is set, the control circuit 51 outputs both the first and second illumination signals to the first display 38 and the second display 39, respectively.

[0223] 2-6-2. Interruption Handling

[0224] In addition to the main program described above, the control circuit 51 also executes an interrupt process (not shown). In this interrupt process, the control circuit 51 stores the logic (positive or negative, HIGH or LOW, 1 or 0) of the voltages of the first to third pulse signals in RAM. In this embodiment, the control circuit 51 periodically and repeatedly executes the interrupt process. In other embodiments, the control circuit 51 may execute the interrupt process based on the edges or voltage levels of the first to third pulse signals or other signals.

[0225] 2-6-3. Pending Judgment and Processing

[0226] like Figure 9 As shown, in the standby determination process, the control circuit 51 first determines, in S210, whether the main power switch 36 has been turned on based on the logic of the voltage of the main power switch 36 stored in RAM. If the main power switch 36 is not turned on (S210: NO), the control circuit 51 immediately ends the standby determination process.

[0227] With the main power switch 36 turned on (S210: YES), the control circuit 51 determines whether the reciprocating motion tool 1 is in standby mode. More specifically, the control circuit 51 determines whether a standby flag is set. When the control circuit 51 is activated, the standby flag is cleared.

[0228] When the reciprocating motion tool 1 is in standby mode (S220: YES), the control circuit 51 switches to S230, stops the output of the RC signal, and ends the standby determination process. As a result, the power supply circuit 52 switches to the off state, and the power supply to the reciprocating motion tool 1 is disconnected.

[0229] If the reciprocating motion tool 1 is not in standby mode (S220: NO), the control circuit 51 proceeds to S240 and determines whether the trigger switch 21 has been turned on. More specifically, the control circuit 51 determines whether the trigger switch 21 has been turned on based on the logic of the output of the second latch circuit 58 stored in RAM. In other words, the control circuit 51 determines whether the trigger switch 21 has been turned on based on whether there is motor current flowing.

[0230] If the trigger switch 21 is turned on (S240: YES), the control circuit 51 immediately ends the standby determination process. If the trigger switch 21 is turned off (S240: NO), the control circuit 51 proceeds to S250 and determines, based on the logic of the voltage of the contactor switch 20 stored in RAM, whether the contactor switch 20 has been turned on.

[0231] When contactor switch 20 is turned on (S250: YES), control circuit 51 immediately ends the standby determination process. When contactor switch 20 is turned off (S250: NO), control circuit 51 proceeds to S260, causing reciprocating motion tool 1 to move to the standby state and ending the standby determination process. In S260, control circuit 51 (i) sets the standby flag and (ii) outputs an RC signal.

[0232] 2-6-4. Motor Control Processing

[0233] like Figure 10 As shown, in the motor control process, the control circuit 51 first determines in S310, based on the logic of the voltage of the contactor switch 20 stored in RAM, whether the contactor switch 20 has been turned on.

[0234] When contactor switch 20 is open (S310: NO), control circuit 51 immediately terminates motor control processing. When contactor switch 20 is closed (S310: YES), control circuit 51 proceeds to S320. In S320, control circuit 51 outputs the corresponding PWM signal to the selected high-side switch and the selected low-side switch (i.e., the combination of the high-side switch and the low-side switch that causes rotor 26 to fail to rotate). The corresponding PWM signal has the initial duty cycle described above.

[0235] In the following S330, the control circuit 51 determines whether a first predetermined time (e.g., 5 seconds) has elapsed since the start of outputting the corresponding PWM signal. This first predetermined time is set to prevent the nail from being accidentally ejected if the pressing member 6 is held in a state where it is pressed against an object against the user's will. If the first predetermined time has elapsed (S330: YES), the control circuit 51 proceeds to S340, stops the output of the corresponding PWM signal, and ends the motor control process.

[0236] If the first predetermined time has not elapsed (S330: NO), the control circuit 51 proceeds to S350, and based on the logic of the output of the second latch circuit 58 stored in RAM, determines whether the trigger switch 21 has been turned on. If the trigger switch 21 is turned off (S350: NO), the control circuit 51 immediately terminates the motor control process.

[0237] With trigger switch 21 already turned on (S350: YES), control circuit 51 proceeds to S360 to determine whether the reciprocating motion tool 1 is set to continuous firing mode. More specifically, control circuit 51 determines whether a continuous firing mode flag is set. When control circuit 51 is activated, the continuous firing mode flag is cleared. In reciprocating motion tool 1, whenever the user presses mode selection switch 37, the operating mode of reciprocating motion tool 1 is switched between single-fire mode and continuous firing mode. Therefore, control circuit 51 sets or clears the continuous firing mode flag based on the logic of the voltage of mode selection switch 37 stored in RAM.

[0238] With the reciprocating tool 1 set to continuous firing mode (S360: YES), the control circuit 51 proceeds to S370 and sets the drive permission flag. The drive permission flag indicates that the drive of the nail is permitted. In the following S380, the control circuit 51 outputs a switch-on signal to the 7th switch Q7, turning on the 7th switch Q7, and proceeds to S410.

[0239] When the reciprocating motion tool 1 is set to single-shot mode (S360: NO), the control circuit 51 proceeds to S390 to determine whether a second predetermined time (e.g., 50 milliseconds) has elapsed. This second predetermined time is set to prevent the reciprocating motion tool 1 from driving in a nail when an operation prohibited in single-shot mode, where the pressing component 6 is pressed against the workpiece while the trigger 9 is pulled, is performed. If the second predetermined time has elapsed (S390: YES), the control circuit 51 proceeds to S370.

[0240] If the second specified time has not elapsed (S390: NO), the control circuit 51 switches to S400 and clears the input permission flag.

[0241] In the following S410, the control circuit 51 performs drive processing.

[0242] In the drive process, the control circuit 51 performs the soft start described above when the enable flag is set. When the soft start is complete, the control circuit 51 sets the duty cycle of the PWM signal output to the selected high-side switch and the selected low-side switch (that is, the high-side switch and the low-side switch that help rotate the rotor 26) to 100%.

[0243] If the input permission flag is cleared, the control circuit 51 immediately terminates the drive process.

[0244] In the following S420, control circuit 51 performs a stop procedure. Details of the stop procedure will be described later.

[0245] When the stop process is complete, control circuit 51 switches to step S430 to determine whether the electric motor 24 has stopped. More specifically, control circuit 51 determines whether a motor stop flag is set. The motor stop flag indicates that the electric motor 24 has stopped.

[0246] If the electric motor 24 has not stopped (i.e., the motor stop sign has been cleared) (S430: NO), the control circuit 51 proceeds to S440. In S440, the control circuit 51 outputs a switch-on signal to the 7th switch Q7, thereby turning on the 7th switch Q7. In other words, the control circuit 51 continuously outputs a switch-on signal to the 7th switch Q7, thereby keeping the 7th switch Q7 in its on state.

[0247] When the electric motor 24 has stopped (i.e., the motor stop sign is set) (S430: YES), the control circuit 51 proceeds to S450. In S450, the control circuit 51 outputs a switch-off signal to the 7th switch Q7, thereby disconnecting the 7th switch Q7.

[0248] 2-6-5. Stop processing

[0249] like Figure 11 As shown, in the stop process, the control circuit 51 first clears the motor stop flag in S500.

[0250] In the following S510, the control circuit 51 determines, based on the logic of the voltage of the first Hall element 34a stored in RAM, whether the first position detection signal has been received.

[0251] If the control circuit 51 receives the first position detection signal (S510: YES), the control circuit 51 proceeds to S520. In S520, the control circuit 51, based on the logic of the voltages of the first to third pulse signals stored in RAM up to this point, determines whether the total number of the first to third pulse signals received between the current reception (the m-th reception; m is any integer greater than 2) and the previous reception (the (m-1)-th reception) of the first position detection signal has reached a predetermined number. In this embodiment, the predetermined number corresponds to the total number of the first to third pulse signals generated during one revolution of the cam 28.

[0252] If the total number of the first to third pulse signals does not reach the specified number (that is, if the cam 28 does not rotate one revolution) (S520: NO), the control circuit 51 immediately ends the stop process, invalidating (or ignoring) the reception of the first position detection signal.

[0253] When the total number of the first to third pulse signals reaches the specified number (that is, when the cam 28 rotates one revolution) (S520: YES), the control circuit 51 switches to S530.

[0254] In S530, the control circuit 51 determines, based on the logic of the voltages of the first Hall element 34a and the second Hall element 34b stored in RAM up to this point, whether the control circuit 51 failed to receive the second position detection signal between the current reception (mth reception) of the first position detection signal and the previous reception ((m-1)th reception).

[0255] If the control circuit 51 receives the second position detection signal (S530: NO), the control circuit 51 proceeds to S540 to execute the first correction process. Details of the first correction process will be described later. When the first correction process is completed, the control circuit 51 ends the stop process.

[0256] If the control circuit 51 fails to receive the second position detection signal (S530: YES), the control circuit 51 proceeds to S550 and sets an error flag.

[0257] In the following S560, the control circuit 51 outputs a PWM signal with a specified duty cycle (e.g., 100%) to at least two of the fourth to sixth switches Q4 to Q6, causing the electric motor 24 to short-circuit brake, thereby ending the stop process.

[0258] If the control circuit 51 does not receive the first position detection signal in S510 (S510: NO), the control circuit 51 proceeds to S570. In S570, the control circuit 51 determines, based on the logic of the voltage of the second Hall element 34b stored in RAM, whether the second position detection signal has been received.

[0259] When the control circuit 51 receives the second position detection signal (S570: YES), the control circuit 51 proceeds to S580 and, based on the logic of the voltages of the first to third pulse signals stored in RAM up to this point, determines whether the total number of the first to third pulse signals received between the current reception (the nth reception; n is any integer greater than 2) and the previous reception (the (n-1)th reception) has reached the aforementioned predetermined number.

[0260] If the total number of the first to third pulse signals does not reach the specified number (that is, if the cam 28 does not rotate one revolution) (S580: NO), the control circuit 51 immediately ends the stop process, thereby invalidating (or ignoring) the reception of the second position detection signal.

[0261] When the total number of the first to third pulse signals reaches the specified number (that is, when the cam 28 rotates one revolution) (S580: YES), the control circuit 51 switches to S590.

[0262] In S590, the control circuit 51 determines, based on the logic of the voltages of the first Hall element 34a and the second Hall element 34b stored in RAM up to this point, whether the control circuit 51 failed to receive the first position detection signal between the current reception (nth reception) of the second position detection signal and the previous reception ((n-1)th reception).

[0263] If the control circuit 51 fails to receive the first position detection signal (S590: YES), the control circuit 51 proceeds to S550. If the control circuit 51 receives the first position detection signal (S590: NO), the control circuit 51 proceeds to S600.

[0264] In S600, the control circuit 51 determines whether a pre-specified third predetermined time has elapsed since the start of driving the electric motor 24. The third predetermined time is set to be any time that would not elapse if the reciprocating motion tool 1 were operating normally. If the third predetermined time has not elapsed (S600: NO), the control circuit 51 immediately terminates the stop process.

[0265] After the third specified time has elapsed (S600: YES), the control circuit 51, in the same manner as S560, causes the electric motor 24 to short-circuit brake.

[0266] In the following S620, the control circuit 51 determines, based on the logic of the voltages of the first to third pulse signals stored in RAM up to this point, whether the electric motor 24 has stopped. If the electric motor 24 has not stopped (S620: NO), the control circuit 51 immediately ends the stop process.

[0267] If the electric motor 24 has stopped (S620: YES), the control circuit 51 proceeds to S630 and sets the motor stop flag. In the following S640, the control circuit 51 performs the second correction process. Details of the second correction process will be described later.

[0268] When the second correction process is completed, the control circuit 51 stops the process.

[0269] If the control circuit 51 does not receive the second position detection signal in S570 (S570: NO), the control circuit 51 proceeds to S650 to determine whether the remaining drive time has elapsed. The remaining drive time is calculated in the first correction process, as described later.

[0270] If the remaining drive time has not elapsed (S650: NO), control circuit 51 proceeds to S620. If the remaining drive time has elapsed (S650: YES), control circuit 51 proceeds to S660.

[0271] In S660, control circuit 51 sets the duty cycle of all PWM signals from the 1st to the 6th to 0%, causing electric motor 24 to switch to free-running mode. Afterwards, control circuit 51 proceeds to S620.

[0272] 2-6-6. First Correction Process

[0273] like Figure 12 As shown, in the first correction process, the control circuit 51 first calculates the current rotational speed of the electric motor 24 in S710 based on the logic of the voltage of the first to third pulse signals stored in RAM up to this point.

[0274] In the following S720, the control circuit 51 calculates: (i) the difference between the pre-specified reference rotational speed and (ii) the calculated current rotational speed (reference rotational speed - current rotational speed).

[0275] In the following S730, the control circuit 51 calculates the remaining drive time based on the calculated difference. In the control circuit 51, the remaining drive time is set as a function of the difference. In this embodiment, the remaining drive time is: as follows... Figure 13 As shown by the solid line, it is set to be a nonlinear function that increases as the difference increases. In other embodiments, the remaining drive time can be a linear function of the difference.

[0276] 2-6-7. Second Correction Process

[0277] like Figure 14 As shown, in the second correction process, the control circuit 51 first determines in S810 whether the electric motor 24 has stopped before the control circuit 51 receives the second position detection signal, based on (i) the logic of the voltage of the second Hall element 34b stored in RAM up to this point and (ii) the logic of the voltage of the first to third pulse signals stored in RAM up to this point.

[0278] If the electric motor 24 has stopped before the control circuit 51 receives the second position detection signal (S810: YES), the control circuit 51, in S820, as... Figure 13 As shown by the dashed line above, the fixed value α1 is added to the function described above used in the first correction process. As a result, the remaining drive time subsequently calculated in the first correction process is increased by the fixed value α1. The fixed value α1 is: an arbitrary value specified beforehand.

[0279] If the electric motor 24 has not stopped before the control circuit 51 receives the second position detection signal (S810: NO), the control circuit 51 proceeds to S830 to determine whether the rotational speed of the electric motor 24 at the time the second position detection signal is received is higher than a specified rotational speed. This specified rotational speed has been pre-specified. If the rotational speed of the electric motor 24 is lower than the specified rotational speed (S830: NO), the control circuit 51 immediately terminates the second correction process.

[0280] If the rotational speed of the electric motor 24 exceeds the specified rotational speed (S830: YES), the control circuit 51 switches to S840. In S840, the control circuit 51... Figure 13 As shown by the dashed line below, the function used in the first correction process is subtracted by a fixed value α1. As a result, the remaining drive time calculated in the first correction process is reduced by the fixed value α1. After this, the control circuit 51 ends the second correction process.

[0281] 2-7. Technical Effects of the Implementation Method

[0282] According to the reciprocating motion tool 1 configured as described above, it is possible to detect the occurrence of malfunctions associated with the position detection of the reciprocating component 18, and more specifically, it is possible to detect the occurrence of malfunctions associated with the first magnet 32, the second magnet 33, the first Hall element 34a, or the second Hall element 34b.

[0283] For example, such as Figure 15 As shown, if a malfunction is detected, such as the control circuit 51 failing to receive the first position detection signal and receiving the second position detection signal instead, the electric motor 24 will be stopped immediately, and the movement of the reciprocating component 18 will also be stopped immediately. At this time, both the first display 38 and the second display 39 of the reciprocating motion tool 1 will be illuminated to notify the user of the malfunction.

[0284] Furthermore, in the reciprocating motion tool 1, through the processing of S520 and S580, it is possible to suppress the situation where, at the time when the electric motor 24 fails to bring the reciprocating component 18 to the stop preparation position or the waiting position, the control circuit 51 receives electrical noise as the first position detection signal or the second position detection signal, and thus the control circuit 51 falsely detects the occurrence of the malfunction.

[0285] Furthermore, the reciprocating motion tool 1 is configured to detect the position of the reciprocating component 18 using a magnetic field. Therefore, compared to a reciprocating motion tool 1 configured to detect the position of the reciprocating component 18 mechanically, the reciprocating motion tool 1 exhibits superior durability. Moreover, compared to a reciprocating motion tool 1 configured to detect the position of the reciprocating component 18 optically, this type of reciprocating motion tool 1 is less susceptible to dust interference during the position detection of the reciprocating component 18.

[0286] Furthermore, in the reciprocating motion tool 1, since the first Hall element 34a and the second Hall element 34b are arranged on the radially outer side of the support 31, the size of the reciprocating motion tool 1 in the direction that intersects the support 31 radially can be reduced.

[0287] In addition, in the reciprocating motion tool 1, the support 31 is a non-magnetic body, so the first Hall element 34a or the second Hall element 34b can easily detect the S pole of the first magnet 32 ​​or the N pole of the second magnet 33.

[0288] 2-8. Correspondence of terms

[0289] In this embodiment, the top dead center of the reciprocating component 18 corresponds to an example of the first dead center in the summary of the embodiment, and the bottom dead center of the reciprocating component 18 corresponds to an example of the second dead center in the summary of the embodiment. The stop preparation position corresponds to an example of the first position in the summary of the embodiment, and the waiting position corresponds to an example of the second position in the summary of the embodiment. The trigger switch 21 corresponds to an example of the first manual switch in the summary of the embodiment, and the contactor switch 20 corresponds to an example of the second manual switch in the summary of the embodiment. The S pole of the first magnet 32 ​​corresponds to an example of the first magnetic pole in the summary of the embodiment, and the N pole of the second magnet 33 corresponds to an example of the second magnetic pole in the summary of the embodiment. The first to third pulse signals each correspond to an example of the rotational position signal in the summary of the embodiment.

[0290] 2-9. Variations

[0291] This invention is not limited to the above-described embodiments and can be implemented in various modifications.

[0292] In a certain variation, the support 31 may only have one of the first magnet 32 ​​and the second magnet 33, and the Hall IC 34 may only have one of the first Hall element 34a and the second Hall element 34b.

[0293] In this case, the control circuit 51 can detect the occurrence of an adverse condition associated with the first magnet 32 ​​or the first Hall element 34a based on the fact that the total number of the first to third pulse signals received between the m-th and (m-1)-th receptions of the detection signal at the first position does not reach the aforementioned predetermined number.

[0294] Alternatively, the control circuit 51 may detect the occurrence of an adverse condition associated with the second magnet 33 or the second Hall element 34b based on the fact that the total number of the first to third pulse signals received between the nth and (n-1)th receptions of the detection signal at the second position does not reach the aforementioned predetermined number.

[0295] In a certain variation, S600, which stops the processing, can be removed.

[0296] In a certain variation, the waiting position of the reciprocating component 18 may be different from the position that causes the reciprocating component 18 to stop.

[0297] 2-10. Supplement

[0298] Furthermore, multiple functions performed by one component in the above embodiments can be performed by multiple components, and one function performed by one component can be performed by multiple components. Additionally, multiple functions performed by multiple components can be performed by one component, and one function performed by multiple components can be performed by one component. Furthermore, a portion of the configuration in the above embodiments can be omitted. Furthermore, at least a portion of the configuration in one of the above embodiments can be added to, or substituted for, the configuration in another of the above embodiments.

Claims

1. A reciprocating motion tool, characterized in that, The reciprocating motion tool has the following features: The reciprocating component is configured to reciprocate between the first dead point and the second dead point; The first position detector is configured to output a first position detection signal whenever the reciprocating component reaches the first position in at least one reciprocating motion; A second position detector, which (i) differs from the first position detector and (ii) is configured to output a second position detection signal whenever the reciprocating component reaches a second position during at least one reciprocating motion, wherein the second position is located after the first position during the at least one reciprocating motion of the reciprocating component; and A control circuit is configured to receive a first position detection signal from the first position detector, receive a second position detection signal from the second position detector, and detect the occurrence of an adverse condition associated with the first position detector or the second position detector based on (i) the control circuit failing to receive the second position detection signal between the m-th and m-1-th receptions of the first position detection signal, or (ii) the control circuit failing to receive the first position detection signal between the n-th and n-1-th receptions of the second position detection signal, wherein m and n are any integers greater than 2.

2. The reciprocating motion tool according to claim 1, characterized in that, The reciprocating motion tool also has: The first manual switch is configured to be manually operated by the user of the reciprocating motion tool; An electric motor is configured to generate driving force; A drive circuit configured to drive the electric motor; and A transmission device configured to transmit the driving force of the electric motor to the reciprocating component at least during the stroke of the reciprocating component from the second dead point to the first dead point. The control circuit is configured to control the drive circuit in such a way that the electric motor is driven at least based on the first manual switch being manually operated.

3. The reciprocating motion tool according to claim 2, characterized in that, The transmission device includes a speed reducer, which (i) has a preset speed reduction ratio and (ii) is configured to convert the driving force of the electric motor into a reduced output and transmit it to the reciprocating component.

4. The reciprocating motion tool according to claim 2 or 3, characterized in that, The control circuit is configured to control the drive circuit by stopping the drive of the electric motor based on the detection of the occurrence of the adverse condition.

5. The reciprocating motion tool according to any one of claims 2 to 4, characterized in that, The control circuit is configured to control the drive circuit by braking the electric motor based on the detection of the adverse condition by the control circuit.

6. The reciprocating motion tool according to any one of claims 2 to 5, characterized in that, The electric motor has a rotor. The reciprocating motion tool includes a rotational position detector, which is configured to output a rotational position signal indicating that the rotor has rotated by a predetermined angle to the control circuit. The control circuit is configured to invalidate the m-th reception of the first position detection signal or the n-th reception of the second position detection signal based on (i) the failure to receive a predetermined number of rotation position signals from the rotation position detector between the m-th reception and the (m-1)-th reception of the first position detection signal, or (ii) the failure to receive the predetermined number of rotation position signals from the rotation position detector between the n-th reception and the (n-1)-th reception of the second position detection signal.

7. The reciprocating motion tool according to any one of claims 2 to 6, characterized in that, The control circuit is configured to output a pulse width modulation signal to the drive circuit to control the drive circuit. The drive circuit is configured to drive the electric motor based on the pulse width modulation signal.

8. The reciprocating motion tool according to any one of claims 2 to 7, characterized in that, The reciprocating motion tool also has: A crimping component, configured to be crimped onto a workpiece by the user; and The second manual switch is configured to be pressed against the workpiece by the pressing member and thus manually operated. The control circuit is configured to control the drive circuit in such a way that the electric motor is driven by both the first manual switch and the second manual switch being manually operated.

9. The reciprocating motion tool according to any one of claims 2 to 8, characterized in that, The reciprocating motion tool has the following features: A cylinder containing compressed gas; and A piston, which (i) is located inside the cylinder, and (ii) exerts force on the reciprocating component at the second dead center by the compressed gas. The reciprocating component is configured to be driven from the first dead point to the second dead point by the piston.

10. The reciprocating motion tool according to any one of claims 1 to 9, characterized in that, The first position detector includes: (i) a first magnet, and (ii) a first Hall element configured to detect a first magnetic pole of the first magnet, and is configured such that, corresponding to the reciprocating component having reached the first position, the first Hall element detects the first magnetic pole of the first magnet and outputs the first position detection signal. The second position detector includes: (i) a second magnet, and (ii) a second Hall element configured to detect a second magnetic pole of the second magnet, and is configured such that, corresponding to the reciprocating component having reached the second position, the second Hall element detects the second magnetic pole of the second magnet and outputs the second position detection signal. The second magnetic pole has a polarity opposite to that of the first magnetic pole.

11. The reciprocating motion tool according to claim 10 when dependent on any one of claims 2 to 9, characterized in that, The transfer device includes: A cam, which (i) has an outer periphery having a plurality of pins arranged circumferentially on the cam, and (ii) is configured to rotate by the driving force of the electric motor; and The support (i) holds the first magnet and the second magnet, and (ii) is configured to rotate together with the cam. The reciprocating component (i) extends between the first stop and the second stop, (ii) has a plurality of racks in its extending direction, and (iii) is configured to be driven from the second stop toward the first stop by engaging the plurality of racks with the plurality of pins respectively.

12. The reciprocating motion tool according to claim 11, characterized in that, The first magnetic pole and the second magnetic pole are directed toward the radially outer side of the support.

13. The reciprocating motion tool according to claim 11 or 12, characterized in that, The cam and the bracket are configured to rotate around the same axis.

14. The reciprocating motion tool according to claim 13, characterized in that, The electric motor includes a rotor that acts as the same shaft.

15. The reciprocating motion tool according to any one of claims 11 to 14, characterized in that, The support is a non-magnetic material.

16. The reciprocating motion tool according to any one of claims 9 to 15, characterized in that, The reciprocating component is configured such that: (i) it is located at the first dead center, corresponding to the piston being located at its top dead center; and (ii) it is located at the second dead center, corresponding to the piston being located at its bottom dead center.

17. The reciprocating motion tool according to any one of claims 1 to 16, characterized in that, The first position corresponds to the stop preparation position for preparing the reciprocating component to stop. The second position corresponds to: (i) a stop position that stops the reciprocating component, and / or (ii) a waiting position that allows the reciprocating component to wait for at least one next reciprocating action.

18. A method for detecting the occurrence of defects associated with the position detection of reciprocating components in a reciprocating motion tool, characterized in that, The method comprises the following steps: The reciprocating component reciprocates between the first dead point and the second dead point; The first position detection signal is received from the first position detector in the reciprocating motion tool, wherein the first position detector is configured to output the first position detection signal whenever the reciprocating component reaches the first position in at least one reciprocating motion; A second position detection signal is received from a second position detector in the reciprocating motion tool, wherein the second position detector (i) is different from the first position detector, and (ii) is configured to output the second position detection signal whenever the reciprocating component reaches a second position in at least one reciprocating motion, the second position being located after the first position in the at least one reciprocating motion of the reciprocating component; and The occurrence of an adverse condition associated with the first position detector or the second position detector is detected based on (i) the failure to receive the second position detection signal between the m-th and m-1th receptions of the first position detection signal, or (ii) the failure to receive the first position detection signal between the n-th and n-1th receptions of the second position detection signal, where m and n are any integers greater than 2.

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