Trigger switch, electric power tool including the same, and control method and control program of trigger switch

Abstract

To provide a trigger switch and a power tool capable of preventing a driving part from being erroneously driven by a user's operation in a state that a switching lever is at a neutral position.SOLUTION: The trigger switch 10 includes a trigger 10a, a trigger plate 15a, a detector 15b, a switching lever position detector 15e, and a controller 19. The detection portion 15b detects the movement of the trigger plate 10a in accordance with the pushing operation to the trigger 15a. The switching lever position detection unit 15e detects that the switching lever 14 for switching the driving direction of the motor M1 is in a neutral position. A control part 19 permits the drive of the motor 15b when the detection part 15a detects the movement of the trigger plate M1, and prohibits the drive of the motor 15e regardless of the push-in operation to the trigger 10a in a state where the switching lever position detection part M1 detects that the switching lever 14 is at the neutral position.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a trigger switch for driving a drive unit of, for example, a power tool, and a power tool including the trigger switch. [Background technology]

[0002] 2. Description of the Related Art In recent years, trigger switches have been used that control the driving of a driving unit of a power tool or the like by pressing a trigger. For example, Patent Document 1 discloses a trigger switch in which a switching mechanism (plunger) is provided with a brush that constitutes a sliding contact that has the function of switching the drive unit on / off and a brush that constitutes a sliding contact that adjusts the output of the drive unit. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2020-30999 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the above-described conventional trigger switch has the following problems. In other words, the sliding contact of the trigger switch disclosed in the above publication has an electrode formed on a substrate and a brush which is a sliding electrode portion provided on the switching mechanism, and by moving the switching mechanism, the brush is switched between a state in which it contacts the electrode (a state in which it has moved to a position in which it contacts the electrode) and a state in which it does not contact the electrode (a state in which it has moved to a position in which it does not contact the electrode).

[0005] The trigger switch has a function to lock the operation of the trigger when the switching lever, which is operated to switch the rotation direction (forward / reverse) of the drive unit, is in the neutral position. In this case, even when the switching lever is in the neutral position, if the user tries to operate the trigger with a strong force, the trigger may be pushed in due to the deflection of the mechanism, releasing the locking mechanism and causing the drive unit to operate.

[0006] An object of the present invention is to provide a trigger switch that can prevent the drive unit from being accidentally driven by a user's operation when the switching lever is in the neutral position, and a power tool equipped with the trigger switch. [Means for solving the problem]

[0007] A trigger switch according to a first aspect of the present invention is a trigger switch that drives a drive unit in response to a trigger depression operation, and includes a trigger, a detectable portion, a detection portion, a switching lever position detection portion, and a control portion. The trigger moves when the trigger is depressed. The detectable portion moves in conjunction with the trigger. The detection portion detects the movement of the detectable portion in response to a trigger depression operation. The switching lever position detection portion detects that a switching lever that switches the drive direction of the drive unit is in a neutral position. The control portion permits the drive unit to be driven when the detection portion detects the movement of the detectable portion, and prohibits the drive unit from being driven when the switching lever position detection portion detects that the switching lever is in the neutral position, regardless of the trigger depression operation.

[0008] Here, when it is detected that a switching lever for switching the drive direction of a drive unit included in a power tool or the like is in a neutral position, control is performed to prohibit the drive unit from being driven. Here, the trigger switch is used to drive a drive motor (drive unit) mounted on a power tool or the like, for example. The detectable portion and detecting portion included in the trigger switch may be configured so that the detectable portion is detected by a sensor, or may be configured as NC (Normal Close) contacts that are in a contact state until the trigger is pressed and become non-contact when the pressing operation is released, or may be configured as NO (Normal Open) contacts that are in a non-contact state until the trigger is pressed and become contact when the pressing operation is released.

[0009] This means that when it is detected that the switching lever that switches the drive direction of the drive unit is in the neutral position, the drive unit can be controlled so that it will not be driven even if the user forcibly presses the trigger and the detection unit detects movement of the detected part. As a result, it is possible to prevent the drive unit from being driven by mistake by a user operation when the switching lever is in the neutral position.

[0010] A trigger switch according to a second aspect of the present invention is the trigger switch according to the first aspect of the present invention, wherein the control section prohibits output of the drive signal to the drive section. As a result, when the switching lever is detected to be in the neutral position, even if the user presses the trigger forcefully, no drive signal is output, thereby preventing the drive unit from being driven.

[0011] A trigger switch according to a third aspect of the present invention is the trigger switch according to the first or second aspect of the present invention, wherein the switching lever switches the rotation direction of the drive unit. This allows, for example, the rotation direction (forward / reverse) of a drive unit such as a motor mounted on a power tool to be switched using a switching lever, and the drive unit can be controlled so that it is not driven when the switching lever is in the neutral position.

[0012] A fourth aspect of the present invention provides a power tool including a main body having a drive unit and a trigger switch that drives the drive unit in response to a pressing operation of a trigger. The trigger switch has a trigger that moves when pressed, a detectable part that moves in conjunction with the trigger, and a detector that detects the movement of the detectable part in response to a pressing operation of the trigger. The main body has a drive unit, a switching lever, a switching lever position detector, and a control unit. The switching lever switches the drive direction of the drive unit. The switching lever position detector detects that the switching lever is in a neutral position. The control unit permits the drive unit to be driven when the detector detects the movement of the detectable part, and prohibits the drive unit from being driven when the switching lever position detector detects that the switching lever is in the neutral position, regardless of a pressing operation of the trigger.

[0013] Here, when it is detected that a switching lever for switching the drive direction of a drive unit included in a power tool or the like is in a neutral position, control is performed to prohibit the drive unit from being driven. Here, the trigger switch is used to drive a drive motor (drive unit) mounted on a power tool or the like, for example. The detectable portion and the detecting portion included in the trigger switch may form NC (Normal Close) contacts that are in contact until the trigger is pressed and become non-contact when the pressing operation is released, or they may form NO (Normal Open) contacts that are non-contact until the trigger is pressed and become contact when the pressing operation is released.

[0014] This means that when it is detected that the switching lever that switches the drive direction of the drive unit is in the neutral position, the drive unit can be controlled so that it will not be driven even if the user forcibly presses the trigger and the detection unit detects movement of the detected part. As a result, it is possible to prevent the drive unit from being driven by mistake by a user operation when the switching lever is in the neutral position.

[0015] A power tool according to a fifth aspect of the present invention is the power tool according to the fourth aspect of the present invention, wherein the switching lever has a locking mechanism that locks the trigger from being pressed when the switching lever is in a neutral position. This allows the trigger to be locked so that it cannot be pressed again even if the user accidentally presses the trigger while the switching lever that switches the drive direction of the drive unit is in the neutral position.

[0016] A sixth aspect of the present invention relates to a method for controlling a trigger switch that drives a drive unit in response to a trigger depression operation, and includes the steps of permitting drive of the drive unit when a detection unit detects movement of a detectable unit, and prohibiting drive of the drive unit regardless of depression of the trigger when a switching lever position detection unit detects that the switching lever is in the neutral position. The trigger switch includes a trigger that moves in response to a depression operation, a detectable unit that moves in conjunction with the trigger, a detection unit that detects movement of the detectable unit in response to a trigger depression operation, and a switching lever position detection unit that detects that the switching lever, which switches the drive direction of the drive unit, is in the neutral position.

[0017] Here, when it is detected that a switching lever for switching the drive direction of a drive unit included in a power tool or the like is in a neutral position, control is performed to prohibit the drive unit from being driven. Here, the trigger switch is used to drive a drive motor (drive unit) mounted on a power tool or the like, for example. The detectable portion and detecting portion included in the trigger switch may be configured so that the detectable portion is detected by a sensor, or may be configured as NC (Normal Close) contacts that are in a contact state until the trigger is pressed and become non-contact when the pressing operation is released, or may be configured as NO (Normal Open) contacts that are in a non-contact state until the trigger is pressed and become contact when the pressing operation is released.

[0018] This means that when it is detected that the switching lever that switches the drive direction of the drive unit is in the neutral position, the drive unit can be controlled so that it will not be driven even if the user forcibly presses the trigger and the detection unit detects movement of the detected part. As a result, it is possible to prevent the drive unit from being driven by mistake by a user operation when the switching lever is in the neutral position.

[0019] A seventh aspect of the present invention provides a control program for a trigger switch that drives a drive unit in response to a trigger depression operation, the control program causing a computer to execute a trigger switch control method including the steps of permitting drive of the drive unit when a detection unit detects movement of a detectable unit, and prohibiting drive of the drive unit regardless of depression of the trigger when a switching lever position detection unit detects that the switching lever is in the neutral position. The trigger switch includes a trigger that moves in response to a depression operation, a detectable unit that moves in conjunction with the trigger, a detection unit that detects movement of the detectable unit in response to a trigger depression operation, and a switching lever position detection unit that detects that the switching lever, which switches the drive direction of the drive unit, is in the neutral position.

[0020] Here, when it is detected that a switching lever for switching the drive direction of a drive unit included in a power tool or the like is in a neutral position, control is performed to prohibit the drive unit from being driven. Here, the trigger switch is used to drive a drive motor (drive unit) mounted on a power tool or the like, for example. The detectable portion and detecting portion included in the trigger switch may be configured so that the detectable portion is detected by a sensor, or may be configured as NC (Normal Close) contacts that are in a contact state until the trigger is pressed and become non-contact when the pressing operation is released, or may be configured as NO (Normal Open) contacts that are in a non-contact state until the trigger is pressed and become contact when the pressing operation is released.

[0021] This means that when it is detected that the switching lever that switches the drive direction of the drive unit is in the neutral position, the drive unit can be controlled so that it will not be driven even if the user forcibly presses the trigger and the detection unit detects movement of the detected part. As a result, it is possible to prevent the drive unit from being driven by mistake by a user operation when the switching lever is in the neutral position. [Effects of the Invention]

[0022] The trigger switch according to the present invention can prevent the drive unit from being erroneously driven by a user's operation when the switching lever is in the neutral position. [Brief explanation of the drawings]

[0023] [Figure 1] 1 is a perspective view showing the external configuration of a power tool equipped with a trigger switch according to an embodiment of the present invention; [Figure 2] 2 is a perspective view showing the configuration of a trigger switch mounted on the power tool of FIG. 1. FIG. [Figure 3] FIG. 3 is a side view showing the internal configuration of the trigger switch of FIG. 2. [Figure 4] FIG. 3 is a side view showing an example of the trigger switch in FIG. 2 in a released state. [Figure 5] FIG. 2 is a control block diagram showing the configuration of the power tool shown in FIG. 1. [Figure 6] 1A is a top view showing the state where the switching lever is in the neutral position, and FIG. 1B is a top view showing the state where the trigger is forcibly pressed in the neutral position of FIG. [Figure 7] 1A is a side cross-sectional view showing a state in which the switching lever is in a neutral position, and FIG. 1B is a side cross-sectional view showing a state in which the trigger is forcibly pressed in the neutral position of FIG. [Figure 8] 10A and 10B are diagrams illustrating the F signal, R signal, and drive output that are output when the switching lever of the trigger switch is set to the F (forward), neutral, or R (reverse) direction. DETAILED DESCRIPTION OF THE INVENTION

[0024] A trigger switch according to one embodiment of the present invention will be described below with reference to FIGS. In the present embodiment, more detailed explanation than necessary may be omitted. For example, detailed explanation of well-known matters or redundant explanation of substantially the same configuration may be omitted. This is to avoid unnecessary redundancy in the following explanation and to facilitate understanding by those skilled in the art.

[0025] Furthermore, the applicant provides the accompanying drawings and the following description to enable those skilled in the art to fully understand the present invention, and they are not intended to limit the subject matter described in the claims. The trigger switch 10 according to this embodiment is mounted on a power tool 50 (see FIG. 1) such as an electric drill, an electric screwdriver, an electric wrench, or an electric grinder that includes a drive unit such as a motor. Furthermore, the trigger switch 10 of this embodiment has an NC (Normal Close) contact that is brought into a non-contact state when a circuit provided inside the power tool 50 transitions from an ON position to an OFF position.

[0026] (1) Power tools 50 As shown in FIG. 1, the power tool 50 of this embodiment includes a main body 20 that is held by a user of the power tool 50, and a trigger switch 10 that is attached to the main body 20 and receives a pressing operation by the user.

[0027] As shown in FIG. 1, the power tool 50 has a handle portion (main body 20) extending downward attached to a substantially cylindrical portion 21 to which the tool tip 51 is attached. In the following explanation, for the sake of convenience, the upper side in the posture of the power tool 50 shown in Figure 1 will be referred to as "up," the lower side as "down," the direction in which the trigger 10a of the trigger switch 10 is located (right in the figure) as "front," and the direction in which the trigger 10a is pressed (left in the figure) as "rear."

[0028] The main body 20 is provided with an openable and closable door 20a and a window 20b through which the attachment state of the trigger 10a of the trigger switch 10 can be visually confirmed. 1, the power tool 50 is in the released state, and the trigger switch 10 is not pressed, so the tool bit 51 is not driven to rotate. When the user places his / her finger on the trigger 10a and presses it toward the main body 20 (rearward) from the released state shown in FIG. 1, the motor (drive unit) M1 (see FIG. 5) built into the main body 20 is driven, and the tool bit 51 is rotated. The circuit configuration for controlling the driving and stopping of the motor M1 will be described in detail later.

[0029] (2) Trigger switch 10 The trigger switch 10 of this embodiment is a switch operated by the user when performing various tasks using the power tool 50, and as shown in Figure 2, it includes a trigger 10a to which a pushing operation is input, a plunger 11a, a return spring 11b that biases the trigger 10a, a housing part 12 contained in the main body part 20 of the power tool 50, the housing part 12, a covering member 13, and a switching lever 14 that switches the driving direction of the motor (drive part) M1 (for example, the forward / reverse rotation direction of the tip tool 51).

[0030] The trigger 10a is a member that receives a pressing operation by the user, and the front surface thereof has an arc-shaped portion where the user places his / her finger when operating it. The plunger 11a has a rod-shaped shaft 11aa and a drive switching mechanism 11ab formed continuously with the rear end of the shaft 11aa. The shaft 11aa supports the trigger 10a in a fitted state at its front end.

[0031] As shown in Figures 2 and 3, the housing 12 is a hollow case having a substantially rectangular parallelepiped shape, and is composed of a first cover 12a and a second cover 12b formed symmetrically on the left and right. A drive switching mechanism 11ab is housed in the internal space of the housing 12. A circuit board 16a is attached to the inner surface of the first cover 12a. A circuit (not shown) for driving a motor (drive unit) M1 is disposed on the circuit board 16a.

[0032] A substantially circular through-hole 12e is formed in the front surface of the housing 12, and the rear end (other end side) of the shaft 11aa passes through it. The periphery of the through-hole 12e protrudes forward in a cylindrical shape. A switching lever 14 that switches the rotation direction of the motor M1 is attached to the top surface of the housing 12. The interior space of the housing 12 is divided into two chambers: a lower chamber 12c and an upper chamber 12d.

[0033] A drive switching mechanism 11ab is housed in a lower chamber 12c within the housing 12. An operating direction switching mechanism 14a is housed in an upper chamber 12d. The drive switching mechanism 11ab opens and closes a circuit formed on the substrate 16a to control the motor (drive unit) M1. The drive switching mechanism 11ab moves back and forth in accordance with the movement of the shaft 11aa. In other words, the drive switching mechanism 11ab moves between a pressed position and a released position in accordance with the pressing and releasing of the trigger 10a.

[0034] That is, when the trigger 10a is pressed, the drive switching mechanism 11ab moves backward, thereby driving the motor (drive unit) M1. On the other hand, when the drive switching mechanism 11ab returns forward, the driving of the motor (drive unit) M1 is stopped. The return spring 11b is formed using a spring such as a compression coil spring. As shown in FIGS. 3 and 4, the return spring 11b is wound around the outer periphery of the shaft 11aa on the outside of the housing 12, and biases the shaft 11aa forward, in the direction opposite to the pushing direction. This causes the shaft 11aa, which has been pushed rearward together with the trigger 10a, to return to the forward release position. The front end of the return spring 11b is engaged with the shaft 11aa, and the rear end is engaged with the periphery of the through-hole 12e of the housing 12.

[0035] Furthermore, as shown in FIG. 3, the internal space of the housing 12 is provided with a brush 15d, a flat cable 16c, a cam 16d, a spring 16e, a cam plate 16f, a switching spring 16g, a roller 16h, a switching plate 16i, a roll pin 17a, an E-ring 17b, and a sealing rubber 17c. Brush 15d is attached to the side of drive switching mechanism 11ab, and moves in conjunction with trigger 10a when trigger 10a is pressed. When trigger 10a is in its initial position, brush 15d is detected as being in contact with a pattern (not shown) formed on substrate 16a. When trigger 10a is pressed, brush 15d is released from contact with the pattern formed on substrate 16a and is no longer detected.

[0036] When the pressing operation on trigger 10a exceeds a predetermined threshold (for example, 0.1 to 0.3 mm), brush 15d is no longer detected on the substrate 16a side, and thus the pressing operation on trigger 10a is detected. The flat cable 16c is provided for inputting power from the power tool 50 or outputting signals to the power tool 50.

[0037] The cam 16d is provided to convert the rotational movement of the switching lever 14 into linear movement and to move the position of the cam plate 16f in accordance with the movement of the switching lever 14. The spring 16e is disposed between the cam 16d and the cam plate 16f, and is provided to apply a biasing force in a direction pressing the cam plate 16f toward the base plate 16a, thereby maintaining a constant distance between the cam plate 16f and the base plate 16a.

[0038] The cam plate 16f is fixed to the cam 16d and is provided to transmit the operational state (position) of the switching lever to the base plate 16a, and its position relative to the base plate 16a changes depending on the position of the switching lever . The switching spring 16g is provided to bias the roller 16h in a direction pressing it against the switching plate 16i, thereby generating an operational reaction force when the switching lever 14 rotates.

[0039] The roller 16h receives the biasing force of the switching spring 16g against the switching plate 16i and slides on the uneven surface of the switching plate 16i in conjunction with the rotation of the switching lever 14. This allows the operation reaction force corresponding to the uneven surface to be transmitted to the switching lever 14. The roll pin 17a is provided to secure the trigger cap of the trigger 10a to the plunger 11a.

[0040] The E-ring 17b is fixed onto the plunger 11a and is provided to transmit the reaction force of the return spring 11b to the plunger 11a. The seal rubber 17c is provided to fill structural gaps between the switching lever 14 and the second cover 12b and first cover 12a, thereby ensuring sealing performance. The covering member 13 is formed in a generally cylindrical bellows shape that expands and contracts in the axial direction, and covers the outer periphery of the shaft portion 11aa and the return spring 11b outside the housing portion 12. The front end of the covering member 13 is attached to the shaft portion 11aa. The rear end of the covering member 13 is attached so as to cover the protruding portion of the periphery of the through-hole 12e of the housing portion 12. The covering member 13 is made of a flexible, airtight material such as rubber.

[0041] The operating direction switching mechanism 14a is attached to the switching lever 14, and switches the driving direction (rotation direction (F (forward) / R (reverse))) of the motor (drive unit) M1 by switching the wiring of the circuit that is opened and closed by the drive switching mechanism 11ab when the switching lever 14 is operated. The switching lever 14 is a member that swings left and right in response to a switching operation by the user to switch the drive direction of the motor (drive unit) M1, and transmits the swinging motion to the operating direction switching mechanism 14a. The switching lever 14 also has a locking mechanism 23 that prevents the trigger 10a from being pressed when the switching lever 14 is operated to be positioned in the middle of its swing range (neutral position).

[0042] With the above-described configuration, the trigger switch 10 is incorporated into the power tool 50 and accepts operations by the user. The user of the power tool 50 performs operations such as depressing the trigger 10a and swinging the switching lever 14 to perform a switching operation. When the trigger 10a is pressed, it moves rearward. As the trigger 10a moves rearward, the shaft 11aa attached to the trigger 10a also moves rearward. As the shaft 11aa moves rearward, the drive switching mechanism 11ab connected to the rear end of the shaft 11aa also moves rearward, and the motor (drive unit) M1 is driven. As the shaft 11aa moves rearward, the return spring 11b and the covering member 13 are compressed in the axial direction.

[0043] To stop the motor (drive unit) M1, the user releases the pressure on the trigger 10a. When the pressure on the trigger 10a is released, the biasing force of the return spring 11b moves the trigger 10a, the shaft 11aa, and the drive switching mechanism 11ab forward and returns to the release position. Furthermore, as the shaft 11aa moves forward, the return spring 11b and the covering member 13 extend in the axial direction.

[0044] The trigger switch 10 also has a switching section 15 provided on the substrate 16a. The switching section 15 has a switching circuit. The switching circuit is configured using sensors such as optical sensors, magnetic sensors, electrostatic sensors, electrical resistance sensors, etc. The switching circuit outputs an ON signal or OFF signal according to the position of the trigger 10a detected by a sensor that detects the movement or position of the trigger 10a in a non-contact manner.

[0045] The switching circuit may output an ON signal or an OFF signal in response to contact between the movable contact and the fixed contact caused by the movement or position of the trigger 10a. A trigger plate 15a made of conductive metal is provided on the surface of the drive switching mechanism 11ab on the left side of the switch. As shown in FIG. 3, the trigger plate 15a is attached to the drive switching mechanism 11ab via two springs 16b, and is biased toward the first cover 12a by the springs 16b.

[0046] Furthermore, a detection portion 15b (a portion indicated by a two-dot chain line in FIG. 4) capable of detecting the position of the trigger plate 15a is formed at a rear position on a substrate 16a attached to the inner surface of the first cover 12a. That is, in a released state where the trigger 10a is not being pressed, the trigger plate 15a is in a position (off state) that is displaced from the position of the detection unit 15b in a side view as shown in Fig. 4. At this time, the switching circuit for driving the motor (drive unit) M1 is in a released state, and the rotation of the motor (drive unit) M1 is stopped.

[0047] From this state, when the trigger 10a is pressed, the shaft 11aa and the drive switching mechanism 11ab move backward, and when the movement reaches a predetermined amount, the trigger plate 15a overlaps with the detection part 15b (facing each other) in a side view (ON state), and the motor (drive part) M1 is driven. In this embodiment, the position of the trigger plate 15a, which changes as the pressing operation on the trigger 10a progresses, is sensed, and the motor M1 (drive unit) is controlled so that the rotation speed of the motor M1 increases.

[0048] <Control configuration> Here, the control configuration of the power tool 50 of this embodiment will be described. As shown in FIG. 5, the power tool 50 transmits and receives signals between the main body 20 and the trigger switch 10. The main body 20 has a control unit 22 and a motor (drive unit) M1.

[0049] As shown in FIG. 5, the trigger switch 10 includes a switching lever position detection unit 15e that detects the position (F (forward) / neutral / R (reverse)) of the switching lever 14, a stroke detection unit 18 that detects the stroke amount of the pressing operation on the trigger 10a, and a control unit 19. The switching lever position detection unit 15e receives information from the above-mentioned operating direction switching mechanism 14a as to whether the switching lever 14 is in the F (forward), R (reverse), or neutral position, detects whether the switching lever 14 is in the neutral position, and transmits the information to the control unit 19.

[0050] More specifically, when the switching lever 14 is operated, the switching lever position detector 15e converts the rotational movement of the switching lever 14 into the linear movement of the cam 16d, causing the cam 16d to move vertically. As a result, the position of the switching lever 14 is detected by detecting the position of the cam plate 16f attached integrally with the cam 16d on the base plate 16a side.

[0051] The stroke detection unit 18 detects the amount of depression (stroke amount) of the trigger 10a and transmits it to the control unit 19. The control unit 19 outputs a drive signal to the main body 20 in response to signals from the switching lever position detection unit 15e and the stroke detection unit 18. The control unit 19 is a circuit configured using, for example, a microcomputer using integrated circuits such as various LSIs and VLSIs, electronic elements, and various terminals, and is disposed on a substrate 16a inside the housing 12.

[0052] When the detector 15b detects the movement of the trigger plate 15a, the controller 19 permits the motor M1 to be driven. The controller 19 also controls the rotation direction and rotation speed of the motor M1 in accordance with the position of the switching lever 14 received from the switching lever position detector 15e and the operation amount (stroke amount) of the trigger 10a received from the stroke detector 18. More specifically, when the switching lever position detector 15e detects that the switching lever 14 is in the neutral position, the controller 19 controls the motor M1 to be prohibited from driving even if the user forcibly presses the trigger 10a. In other words, when the switching lever 14 is in the neutral position, the controller 19 does not send a drive signal to the controller 22 of the main body 20 to drive the motor M1, even if the user forcibly presses the trigger 10a, causing part of the component to deform and causing the trigger plate 15a to be detected by the detector 15b.

[0053] In the power tool 50 of this embodiment, when the contact between the brush 15d and the circuit board 16a is released as the trigger 10a is pressed, a signal (ON signal) is transmitted from the switching circuit. That is, as the trigger 10a is pressed further, the control unit 19 transitions from a stopped state (Sleep state) to an activated state.

[0054] <Pushing the trigger 10a> Next, the states of the switching unit 15 (switching circuit) and the control unit 22 and the changes in the device rotation speed when the trigger is pressed will be described. When the trigger switch 10 is in the released state, the brush 15d is in contact with the circuit board 16a. In this state, the control unit 22 is in a stopped (sleep) state. The switching circuit is in the off state (the trigger plate 15a is in the off position), and the motor M1 is stopped. When the trigger 10a is pressed from this state, the plunger 11a moves backward in response to the pressing operation. As the plunger 11a moves backward, the brush 15d transitions to an OFF state in which it is no longer in contact with the substrate 16a, and the control unit 19 of the trigger switch 10 is activated.

[0055] Thereafter, as the trigger 10a continues to be pressed and the plunger 11a moves further backward, the trigger plate 15a enters an ON state where it overlaps with the detection portion 15b, and the motor M1 starts to operate. As the trigger 10a continues to be pressed, the signal from the switching circuit changes, and the rotation speed of the motor M1 increases accordingly. Here, the control when the trigger 10a is forcibly pressed while the switching lever 14 is in the neutral position will be described below.

[0056] In the trigger switch 10 of this embodiment, as shown in FIG. 6(a), when the switching lever 14 is in the neutral position, the locking mechanism 23 restricts the operation of the trigger 10a so that the trigger 10a cannot be pressed. However, if the user presses the switch lever 14 without realizing that it is in the neutral position, depending on the amount of force applied, there is a risk that part of the part may be deformed, as shown in Figure 6(b), and trigger 10a and the part that moves in conjunction with trigger 10a may be pressed in.

[0057] At this time, inside the housing part 12, when viewed from the side, as shown in Figure 7(a), if the trigger plate 15a is in a position where it does not overlap with the detection part 15b, and is pushed to a position where part of the trigger plate 15a overlaps with the detection part 15b, as shown in Figure 7(b), the movement of the trigger plate 15a may be detected by the detection part 15b, and the motor M1 may be driven.

[0058] Therefore, in the trigger switch 10 of this embodiment, as described above, when the switching lever position detection unit 15e detects that the switching lever 14 is in the neutral position, the control unit 19 controls the motor M1 to be prohibited from driving even if the user forcibly presses the trigger 10a. In other words, when the switching lever 14 is in the neutral position, the control unit 19 controls the motor M1 not to be driven to the control unit 22 on the main body 20 side, even if the user forcibly presses the trigger 10a and deforms part of the component, causing the trigger plate 15a to be detected by the detection unit 15b.

[0059] Here, as shown in FIG. 8, when the switching lever 14 is in the F (forward) position, the control unit 19 outputs an F (forward) signal as “High” and an R (reverse) signal as “Low” to the control unit 22 on the main body unit 20 side together with a drive signal. In this case, the drive output is set according to the amount of depression (stroke amount) of the trigger 10a.

[0060] Furthermore, as shown in FIG. 8, when the switching lever 14 is in the R (reverse) position, the control unit 19 outputs an F (forward) signal as “Low” and an R (reverse) signal as “High” to the control unit 22 on the main body 20 side together with the drive signal. In this case, the drive output is set according to the amount of depression (stroke amount) of the trigger 10a, as in the case of F (forward rotation).

[0061] On the other hand, as shown in FIG. 8, when the switching lever 14 is in the neutral position, the control unit 19 outputs the F (forward rotation) signal as “Low” and the R (reverse rotation) signal as “Low” to the control unit 22 on the main body 20 side together with the drive signal. In this case, the drive output is controlled so as not to output a drive signal. This prevents the motor M1 from being driven even if the user accidentally presses the trigger 10a when the switching lever 14 is in the neutral position. Therefore, it is possible to prevent unnecessary power consumption caused by the motor M1 being rotated due to an erroneous pushing operation when the switching lever 14 is in the neutral position.

[0062] <Control method of trigger switch 10> With the above-described configuration, when trigger 10a of trigger switch 10 of this embodiment is pressed, brush 15d, which moves in conjunction with trigger 10a, is released from contact with substrate 16a, which outputs a signal to activate control unit 19 within trigger switch 10, activating control unit 19. When trigger 10a is further pressed, trigger plate 15a is placed in an ON state where it overlaps detection unit 15b, and driving of motor M1 begins.

[0063] In the trigger switch 10 of this embodiment, when the control unit 19 detects that the switching lever 14, which switches the driving direction of the motor M1, is in the neutral position, the control unit 19 performs control to prohibit driving of the motor M1. That is, when the detector 15b detects the movement of the trigger plate 15a, the controller 19 permits the motor M1 to be driven. When the switching lever position detector 15e detects that the switching lever 14 is in the neutral position, the controller 19 prohibits the driving of the motor M1 regardless of whether the trigger 10a is pressed.

[0064] <Major features> The trigger switch 10 of this embodiment is a switch that drives the motor M1 in response to a depression of the trigger 10a, and includes the trigger 10a, a trigger plate 15a, a detection unit 15b, a switching lever position detection unit 15e, and a control unit 19. The trigger 10a moves when the trigger 10a is pressed. The trigger plate 15a moves in conjunction with the trigger 10a. The detection unit 15b detects the movement of the trigger plate 15a in response to a depression of the trigger 10a. The switching lever position detection unit 15e detects that the switching lever 14, which switches the drive direction of the motor M1, is in the neutral position. The control unit 19 permits the motor M1 to be driven when the detection unit 15b detects the movement of the trigger plate 15a, and prohibits the motor M1 from being driven when the switching lever position detection unit 15e detects that the switching lever 14 is in the neutral position, regardless of the depression of the trigger 10a.

[0065] As a result, when it is detected that the switching lever 14, which switches the drive direction of the motor M1, is in the neutral position, even if the user forcibly presses the trigger 10a and the detection unit 15b detects the movement of the trigger plate 15a, the motor M1 can be controlled so that it is not driven. As a result, it is possible to prevent the motor M1 from being driven by mistake by a user operation when the switching lever 14 is in the neutral position.

[0066] [Other embodiments] Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications are possible without departing from the gist of the invention. (A) In the above embodiment, the present invention has been described as being implemented as a trigger switch and a control method for the trigger switch, but the present invention is not limited to this.

[0067] For example, the present invention may be realized as a control program that causes a computer to execute the above-described method for controlling a trigger switch. This control program is stored in a memory (storage unit) mounted on the trigger switch, and the CPU reads the control program stored in the memory and causes the hardware to execute each step. More specifically, the CPU reads the control program and executes each of the steps described above, thereby achieving the same effects as those described above. The present invention may also be realized as a recording medium storing a control program for the trigger switch.

[0068] (B) In the above embodiment, an example has been described in which the control unit 19 provided on the trigger switch 10 side performs control to prohibit driving of the motor M1 when the trigger 10a is pressed while the switching lever 14 is in the neutral position. However, the present invention is not limited to this. For example, a control unit (controller) provided on the main body side of the power tool may be configured to perform control to prohibit the drive unit from being driven when the trigger is pressed while the switching lever is in the neutral position.

[0069] (C) In the above embodiment, an example has been described in which the rotation direction of the motor M1 mounted on the power tool 50 is switched by the switching lever 14. However, the present invention is not limited to this. For example, the drive unit switched by the switching lever may be something other than a motor. Further, instead of a configuration in which the rotation direction is switched by a switching lever, a configuration in which a drive direction other than the rotation direction is switched may be used.

[0070] (D) In the above embodiment, the trigger switch 10 is described as an example of a normally closed (NC) contact that releases contact between the brush 15d and the circuit board 16a when the circuit inside the power tool 50 transitions from the on position to the off position. However, the present invention is not limited to this.

[0071] For example, the present invention may be applied to a trigger switch that constitutes a NO (Normal Open) contact that is released from contact as a circuit provided inside a power tool transitions from an OFF position to an ON position.

[0072] (E) In the above embodiment, an example has been described in which the present invention is applied to the trigger switch 10 mounted on the power tool 50. However, the present invention is not limited to this. For example, the present invention may be applied to a trigger switch mounted on other devices such as a vacuum cleaner or a chainsaw. [Industrial Applicability]

[0073] The trigger switch of the present invention has the effect of preventing the drive unit from being accidentally driven by a user's operation when the switching lever is in the neutral position, and therefore can be widely applied as a switch for driving various drive units. [Explanation of symbols]

[0074] 10 Trigger switch 10a Trigger 11a Plunger 11aa shaft 11ab Drive switching mechanism 11b Return spring 12 Housing 12a 1st cover 12b 2nd cover 12c lower chamber 12d upper chamber 12e through hole 13 Covering material 14 Switching lever 14a Operation direction switching mechanism 15 Switching section 15a Trigger plate (detected part) 15b Detector (detector) 15d brush 15e Switch lever position detector 16a board 16b Spring 16c flat cable 16d Cam 16e spring 16f Cam Plate 16g switching spring 16h Laura 16i Switching Plate 17a Roll Pin 17b E-ring 17c Seal rubber 18 Stroke detection unit 19 Control Unit 20 Main body 20a Door section 20b Window 21 Approximately cylindrical portion 22 Control Unit 23 Locking mechanism 50 Power tools 51 Tip tool M1 Motor (drive unit)

Claims

1. A trigger switch that drives a drive unit when a trigger is pressed, the trigger that moves in response to the pressing operation; a detected part that moves in conjunction with the trigger; a detection unit that detects movement of the detected portion in response to the pressing operation on the trigger; a switching lever position detection unit that detects whether a switching lever that switches the drive direction of the drive unit is in a neutral position; a control unit that permits driving of the drive unit when the detection unit detects movement of the detected unit, and prohibits driving of the drive unit when the switching lever position detection unit detects that the switching lever is in the neutral position regardless of a pressing operation on the trigger; A trigger switch is provided.

2. the control unit prohibits output of a drive signal to the drive unit. The trigger switch according to claim 1 .

3. The switching lever switches the rotation direction of the drive unit.

3. The trigger switch according to claim 1 or 2.

4. A power tool including a main body provided with a drive unit and a trigger switch that drives the drive unit when a trigger is pressed, The trigger switch is the trigger that moves in response to the pressing operation; a detected part that moves in conjunction with the trigger; a detection unit that detects movement of the detected portion in response to the pressing operation on the trigger; It has The main body portion is The drive unit; a switching lever for switching the driving direction of the driving unit; a switching lever position detector that detects whether the switching lever is in a neutral position; a control unit that permits driving of the drive unit when the detection unit detects movement of the detected unit, and prohibits driving of the drive unit when the switching lever position detection unit detects that the switching lever is in the neutral position regardless of a pressing operation on the trigger; It has Power tools.

5. The switching lever has a locking mechanism that locks the trigger from being pressed when the switching lever is in the neutral position. The power tool according to claim 4.

6. A control method for a trigger switch that drives a drive unit in response to a trigger depression operation, comprising: The trigger switch is the trigger that moves in response to the pressing operation; a detected part that moves in conjunction with the trigger; a detection unit that detects movement of the detected portion in response to the pressing operation on the trigger; a switching lever position detection unit that detects whether a switching lever that switches the drive direction of the drive unit is in a neutral position; It is equipped with permitting the driving of the driving unit when the detecting unit detects the movement of the detected unit; prohibiting the driving of the driving unit when the switching lever position detection unit detects that the switching lever is in the neutral position, regardless of a pressing operation on the trigger; A method for controlling a trigger switch comprising:

7. A control program for a trigger switch that drives a drive unit when the trigger is pressed, The trigger switch is the trigger that moves in response to the pressing operation; a detected part that moves in conjunction with the trigger; a detection unit that detects movement of the detected portion in response to the pressing operation on the trigger; a switching lever position detection unit that detects whether a switching lever that switches the drive direction of the drive unit is in a neutral position; It is equipped with permitting the driving of the driving unit when the detecting unit detects the movement of the detected unit; prohibiting the driving of the driving unit when the switching lever position detection unit detects that the switching lever is in the neutral position, regardless of a pressing operation on the trigger; A trigger switch control program that causes a computer to execute a trigger switch control method comprising:

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