JP6675296B2 - Electric tool - Google Patents

Description

  The present invention relates to a power tool such as a drill driver and an impact driver.

  As an electric tool, an electric motor for rotating a tool such as a drill or a driver, trigger switch means for changing the rotation speed of the electric motor, and a rotation speed of the electric motor based on a detection signal from the trigger switch means. And a rotation speed setting unit for setting the rotation speed (see, for example, Patent Document 1).

  In this electric power tool, the trigger switch means includes an operation moving member slidably mounted on the electric tool main body, a magnet attached to the operation moving member, and first and second magnets for detecting magnetic flux from the magnet. A second Hall IC is provided, and the first and second Hall ICs are arranged so as to partially overlap in the sliding direction of the operation moving member. Further, a main switch for detecting the start of movement of the operation moving member is provided, and the main switch detects an initial position (a position where no operation is performed) of the operation moving member.

  When the operation moving member is operated and moved, the main switch is turned on, and current supply to the drive circuit of the electric motor is started. When the operation moving member is further moved slightly, the first Hall IC detects the magnetic flux of the magnet that moves integrally with the operation moving member (at this time, the second Hall IC does not detect the magnetic flux of the magnet). . Thus, the rotation speed setting means generates a low-speed rotation signal based on the detection signal from the first Hall IC, and the electric motor is rotated at a low speed based on the low-speed rotation signal.

When the operation moving member is further moved from this low speed operation state, the first and second Hall ICs detect the magnetic flux of the magnet on the operation moving member side, and rotate based on the detection signal from the first and second Hall ICs. The speed setting means generates a medium-speed rotation signal, and the electric motor is driven to rotate at a medium speed based on the medium-speed rotation signal. Further, when the operation moving member is operated and moved from the medium speed operation state, the second Hall IC detects the magnetic flux of the magnet on the operation moving member side (at this time, the first Hall IC stops detecting the magnetic flux of the magnet ). The rotation speed setting means generates a high-speed rotation signal based on the detection signal from the second Hall IC, and the electric motor is driven to rotate at high speed based on the high-speed rotation signal. In this manner, the operation state of the operation moving member is detected in three stages by one magnet on the operation moving member side and the two Hall ICs (first and second Hall ICs) on the power tool main body side. Can be adjusted in three stages.

Japanese Patent No. 4939673

  However, in this electric tool, it is necessary to provide two Hall ICs on the power tool main body side and one magnet on the operation moving member side in order to detect the three-stage operation state of the operation moving member. There is a problem that the design is somewhat complicated. Further, if it is attempted to detect the operation state of the operation moving member in four or more stages using such a configuration, three or more Hall ICs are required, the circuit design becomes more complicated, and the manufacturing cost increases. There's a problem.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a power tool capable of detecting three or more operation states of an operation moving member with a relatively simple configuration.

The electric tool according to claim 1 of the present invention changes an electric motor main body, an electric motor built in the electric tool main body, a work tool rotated by the electric motor, and a rotation speed of the electric motor. A trigger switch means for, and a power tool comprising a rotation speed setting means for setting the rotation speed of the electric motor based on a detection signal from the trigger switch means,
The trigger switch means includes an operation moving member slidably mounted on the power tool main body, a magnet mounting portion mounted on the operation moving member, and the same pole facing the magnet mounting portion. and mounting the first and second magnets is, the first comprising 1 and a magnetic flux detecting means disposed in the power tool body side a between the second magnet, the rotational speed setting means, the flux detecting means It is configured to set the rotation speed of the electric motor based on a detection signal from
Further, the trigger switch means includes a housing main body that accommodates the first and second magnets and the magnet mounting member, and the operation moving member includes an operation unit and a movement shaft extending from the operation unit into the housing main body. A sliding sleeve is slidably supported by the moving shaft portion, and the magnet mounting member is attached to a distal end of the moving shaft portion, and the operation moving member and the sliding sleeve are connected to each other. A coil spring is interposed by fitting the moving shaft portion therebetween,
Further, the sliding sleeve is provided with a protrusion protruding radially outward, and the housing body is provided with an operation protrusion acting on the protrusion of the slide sleeve. I do.

Further, in the power tool according to claim 2 of the present invention, the housing main body is provided with an initial position holding projection corresponding to an initial position of the operation moving member, and the sliding sleeve side is provided with the initial position holding projection. A contact portion is provided corresponding to the initial position holding projection on the housing body side, and when the operation moving member is at the initial position, the contact portion on the sliding sleeve side is the contact portion on the housing body side. It is characterized by being brought into contact with the initial position holding projection.

Further, in the electric power tool according to claim 3 of the present invention, a pair of first guide projections extending in the sliding direction of the operation moving member are provided on the inner surface of the one-side wall of the housing body, and the other surface wall is provided. A pair of second guide projections extending in the sliding direction of the operation moving member are provided on the inner surface, and the sliding sleeve and the magnet mounting member are provided with the pair of first guide projections and the pair of second guide projections. 2 It is characterized by being slid along the guide ridge.

According to the first aspect of the present invention, the first and second magnets are arranged such that the trigger switch means of the electric tool faces the operation moving member slidably mounted and the operation moving member. And a magnetic flux detecting means disposed between the first and second magnets, wherein the first and second magnets are disposed on the operation moving member side, and the magnetic flux detecting means is disposed on the power tool main body side. Therefore, when the first and second magnets move relative to the magnetic flux detecting means by the operation of the operation moving member, the detection signal of the magnetic flux detecting means becomes continuous, and the rotation speed setting means outputs the detection signal. The rotation speed of the electric motor is set based on Therefore, by setting the rotation speed by dividing the detection signal of the magnetic flux detection means into three ranges, the rotation speed of the electric motor can be switched to three stages, and the rotation speed can be divided into four or more ranges to reduce the rotation speed. By setting, the rotation speed of the electric motor can be switched in four or more stages. Thus, the rotation speed of the electric motor can be switched as desired with a relatively simple configuration. Power tool can be provided relatively inexpensively.
Further, since the first and second magnets are attached to the operation moving member so that the same poles face each other, the operation movement of the operation moving member is converted into a continuous detection signal of the magnetic flux detecting means. By using the detection signal, the rotation speed of the electric motor can be switched as desired. By using a linear Hall IC as the magnetic flux detecting means, the operation movement of the operation moving member can be converted into a substantially linear continuous detection signal of the Hall IC, and the rotation speed corresponding to the moving amount of the operation moving member can be converted. Can be set to
Further, the trigger switch means includes a housing body accommodating the first and second magnets and the magnet mounting member, and the operation moving member has a movement shaft extending from the operation section into the housing body. Since the magnet mounting member is attached to the distal end of the device, the first and second magnets can be moved integrally with the operation moving member by operating the operation moving member. Further, a sliding sleeve is slidably supported by the moving shaft portion, a coil spring is interposed between the operation moving member and the sliding sleeve, and further, a protruding portion is provided on the sliding sleeve. Is provided with an operation protrusion, so that when the operation moving member is operated in the operation direction, the protrusion of the slide sleeve comes into contact with the operation protrusion on the housing body side, thereby restricting the movement of the slide sleeve. As the operation amount of the operation moving member increases, the repulsive force of the coil spring increases, and the operation force of the operation moving member can be increased.

Further, according to the electric tool according to claim 2 of the present invention, the housing body, the initial position holding projection is provided in correspondence with the initial position of the operating movement member, the sliding sleeve side, the housing body Since the contact portion is provided corresponding to the initial position holding projection on the side, the contact portion abuts on the initial position holding projection on the housing body side to hold the operation moving member at the initial position. be able to.

Further, according to the power tool of the present invention, a pair of first guide protrusions is provided on the inner surface of the one surface wall of the housing body, and a pair of second guide protrusions are provided on the inner surface of the other surface wall. Is provided, the sliding sleeve and the magnet mounting member can be reliably slid in the sliding direction (operation direction) along the pair of first guide protrusions and the pair of second guide protrusions. .

1 is a front view schematically showing an embodiment of a power tool according to the present invention. Sectional drawing which shows the trigger switch means of the electric tool of FIG. 1 in the state which has not operated the operation moving member. Sectional drawing by the III-III line in FIG. Sectional drawing by the IV-IV line in FIG. FIG. 3 is a cross-sectional view illustrating the trigger switch unit of FIG. 2 in a state where the operation moving member is slightly operated. FIG. 3 is a cross-sectional view illustrating the trigger switch unit of FIG. 2 in a state where an operation moving member is operated to the maximum. The figure which shows the relationship between the movement amount of an operation moving member, and the detection output of a magnetic flux detection means. FIG. 2 is a block diagram schematically showing a control system of the electric tool in FIG. 1.

  Hereinafter, with reference to the accompanying drawings, a description will be given by applying to a drill driver as an example of a power tool according to the present invention. In FIG. 1, the illustrated power tool (drill driver) includes a power tool main body 2. The power tool main body 2 includes a cylindrical main body 4 and a grip portion 6 protruding from a rear portion of the main body 4. Have. An electric motor 10 (for example, composed of a DC motor) for rotationally driving a drill 8 as a working tool, a gear box 12 drivingly connected to the output side of the electric motor 10 are provided in the main body 4. The chuck means 14 is mounted on the output side of the gear box 12, and a drill 8 as a working tool is detachably mounted on the chuck means 14. Further, a battery 16 (for example, composed of a lithium ion battery) as a power supply of the power tool and a controller 18 for controlling the power tool are built in the grip portion 6.

  In this electric tool, a trigger switch means 20 for controlling the rotation speed of the electric motor 10 is provided. The trigger switch means 20 is disposed near the connection between the main body 4 of the power tool main body 2 and the gripper 6, and is operated by the index finger of the hand holding the gripper 6. A movement detection unit 24 for detecting movement of the moving member 22;

  Referring also to FIGS. 2 to 4, in the illustrated trigger switch means 20, the operation moving member 22 has an operation unit 26 operated by a finger and a movement shaft 28 extending from the operation unit 26. The operation unit 26 is provided at the tip of the moving shaft 28. The operation unit 26 is arranged outside the power tool main body 2, the moving shaft 28 extends from the operation unit 26 into the power tool main body 2, and the movement detection unit 24 is built in the power tool main body 2.

  The movement detecting unit 24 includes a housing body 34 configured by combining a pair of housing members, that is, first and second housing members 30 and 32. An opening 36 is provided at one end of the housing body 34, and a support sleeve 38 is attached to the opening 36, and the movement shaft 28 of the operation moving member 22 extends into the housing body 34 through the support sleeve 38. I have.

  A sliding sleeve 40 and a magnet mounting member 42 are mounted on the distal end side of the moving shaft 28 of the operation moving member 22. The sliding sleeve 40 is slidably mounted on the moving shaft 28, and the magnet mounting member 42 is attached to the tip of the moving shaft 28. In relation to the sliding sleeve 40 and the magnet mounting member 42, first and second guide projections 44, 46 are provided on the housing body 34 side. As shown in FIG. 3, a pair of first guide projections 44 are provided on the inner surface of one side wall (in other words, the first housing member 30) of the housing body 34, and the other surface wall (in other words, the second housing member 32). A pair of second guide projections 46 are provided on the inner surface of the first and second guide projections, and the first and second guide projections 44, 46 are in the sliding direction of the operation moving member 22 (that is, in the left-right direction in FIGS. 2 and 4). 3 in a direction perpendicular to the plane of the drawing).

  A rectangular first step portion 48 is provided on both sides on one side (lower side in FIG. 3) of the sliding sleeve 40 and the magnet mounting member 42, and on both sides on the other side (upper side in FIG. 3). A rectangular second step 50 is provided, and the first step 48 is slidably guided and supported between the pair of first guide projections 44 on the housing body 34 side. Are slidably supported between the pair of second guide projections 46 on the housing body 34 side. Therefore, the sliding sleeve 40 and the magnet mounting member 42 are housed in the housing body 34 in a pair. It is slidably supported along the first guide projection 44 and the pair of second guide projections 46. With this configuration, one end side of the operation moving member 22 (the end side of the moving shaft portion 28) is supported by the housing body 34 via the support sleeve 38, and can be understood from the other end, as understood from FIG. The side (the rear end side of the moving shaft portion 28) is supported by the housing body 34 via the sliding sleeve 40 and the magnet mounting member 42.

  In this embodiment, the movement detecting unit 24 detects the first and second magnets 52 and 54 for detecting the amount of movement of the operation moving member 22, and detects a change in magnetic flux from the first and second magnets 52 and 54. And a magnetic flux detecting means 56 for performing the operation. Referring to FIG. 2, magnet mounting member 42 has a mounting body 58 extending in a sliding direction (left and right direction in FIG. 2), and a first mounting portion 60 is provided at one end (left end in FIG. 2). The second mounting portion 62 is provided at the other end, the first magnet 52 is mounted inside the first mounting portion 60, and the second magnet 54 is mounted on the inner surface of the second mounting portion 62. With this configuration, when the operation moving member 22 is operated in the direction indicated by the arrow 64, the first and second magnets 52, 54 are moved integrally with the magnet via the magnet mounting member 42.

  When attached to the operation moving member 22, the first magnet 52 and the second magnet 54 face each other, and are arranged such that the same poles of the magnets 52 and 54 face each other. That is, the N pole (or S pole) of the first magnet 52 and the N pole (or S pole) of the second magnet 54 face each other.

  A magnetic flux detecting means 56 for detecting a change in the magnetic flux is provided between the first and second magnets 52 and 44. The magnetic flux detecting means 56 is composed of, for example, a linear Hall IC, and is disposed and electrically connected to a circuit board (not shown) attached to the housing body 34, for example. The detection output of the magnetic flux detecting means 56 is such that the operation moving member 22 (the first and second magnets 52, 54) is moved from the initial position shown in FIG. 2 (the position where the magnetic flux detecting means 56 is close to the first magnet 52) in FIG. When the magnetic flux detection means 56 moves to the maximum operation position (position where the magnetic flux detection means 56 approaches the second magnet 54), the detection signal (detection output) of the magnetic flux detection means 56 changes as shown in FIG. As the position moves from the initial position shown to the maximum operation position shown in FIG. 7, the magnitude of the detection signal gradually increases substantially linearly and continuously. For example, it can be obtained by using a linear Hall IC and arranging the first and second magnets 52 and 54 so as to face the same pole.

  In this electric power tool, a coil spring 66 (functioning as an elastic biasing member) is mounted by fitting the moving shaft portion 28 of the operation moving member 22, and one end of the coil spring 66 has a sliding sleeve 40 (specifically, , The bottom of the housing recess 67), and the other end thereof contacts the large-diameter shaft 69 of the operation moving member 22. The coil spring 66 interposed between the sliding sleeve 40 and the operation moving member 22 elastically biases the operation moving member 22 rightward in FIG. 2 (that is, the direction opposite to the direction indicated by the arrow 64), Thereby, the operation moving member 22 is held at the initial position (non-operation position) shown in FIG.

  In this electric power tool, a protrusion 68 is provided at one end (right end in FIG. 2) of the sliding sleeve 40 so as to protrude outward in the radial direction. An operation projection 70 is provided on the first housing member 34 (first housing member 30). With such a configuration, when the operation moving member 22 is at the initial position, as shown in FIG. 2, the protrusion 68 of the sliding sleeve 40 does not contact the operation protrusion 70 on the housing body 34 side. However, when the operation moving member 22 is slightly moved in the operation direction indicated by the arrow 64, the protrusion 68 comes into contact with the operation protrusion 70 on the housing body 34 side as shown in FIG. When the operation moving member 22 is further moved in the operation direction from, as shown in FIG. 6, the operation moving member 22 and the magnet mounting member 42 (both the first and second magnets 52, 54) are moved relative to the sliding sleeve 40. Are relatively moved in the operation direction.

  Further, at the other end (the left end in FIG. 2) of the sliding sleeve 40, a pressing protrusion 72 protruding radially outward is provided, and corresponding to the pressing protrusion 72, the housing body 34 side (Specifically, a main switch 74 is arranged on a circuit board (not shown) attached to the housing body 34). With this configuration, when the operation moving member 22 is at the initial position, as shown in FIG. 2, the pressing protrusion 70 of the sliding sleeve 40 does not press the main switch 74 on the housing body 34 side. However, when the operation moving member 22 is slightly moved in the operation direction indicated by the arrow 64, the pressing protrusion 70 presses the main switch 74 on the housing body 34 side, as shown in FIG. Is turned on, and current is supplied to the electric system of the power tool (for example, the controller 18).

  In this embodiment, an initial position holding projection 78 (see FIG. 4) that projects inward is provided at a predetermined portion of the housing body 34 (specifically, the first housing member 30). When the sliding sleeve 40 is resiliently biased leftward in FIG. 2 by the coil spring 66, the rear end of the sliding sleeve 40 abuts the initial position holding projection 78 to prevent its movement. In the contact state, the coil spring 66 resiliently biases the operation moving member 22 rightward in FIG. 2, and thus the magnet mounting member 42 comes into contact with the sliding sleeve 40, whereby the operation moving member 22 is moved to the position shown in FIG. Is held at the initial position shown in FIG. In this regard, a receiving portion 79 for receiving the initial position holding projection 78 is provided at one end of the magnet mounting member 42. The initial position holding projection 78 may be provided on the second housing member 32 in addition to the first housing member 30.

  The operation of this electric tool is controlled by a control system shown in FIG. 8, the controller 18 for controlling the electric tool includes a control means 82 composed of, for example, a microprocessor electrically mounted on a control circuit board. Is transmitted, and an operation signal from the main switch 74 is also transmitted.

  The illustrated control unit 80 includes a rotation speed setting unit 82, a speed signal generation unit 84, and a motor driving unit 86. The rotation speed setting unit 82 is electrically driven based on a detection signal from the magnetic flux detection unit 56 as described later. The rotation speed of the motor 10 is set, the speed signal generation unit 84 generates a speed signal corresponding to the rotation speed set by the rotation speed setting unit 82, and the motor drive unit 86 is generated by the speed signal generation unit 84. The electric motor 10 is driven as required based on the speed signal.

  In this embodiment, the control means 82 further includes a memory means 88, in which various voltage values set in relation to the detection signal of the magnetic flux detection means 56, that is, the electric motor 10 is rotated at a low speed. The low-speed rotation value V1 to be set, the medium-speed rotation value V2 to set the electric motor 10 to medium-speed rotation, and the high-speed rotation value V3 to set the electric motor 10 to high-speed rotation are registered. Therefore, when the detection signal of the magnetic flux detecting means 56 becomes equal to or higher than the low-speed rotation value V1 (or the medium-speed rotation value V2, the high-speed rotation value V3), the rotation-speed setting means 82 sets the low-speed rotation (or medium-speed rotation, high-speed rotation). Then, the rotation speed signal generating means 84 generates a low speed signal (or a medium speed signal or a high speed signal) based on the low speed rotation (or medium speed rotation, high speed rotation) set by the rotation speed setting means 82, The motor drive unit 86 rotationally drives the electric motor 10 at a low speed (or a medium speed or a high speed) based on the generated low speed signal (or a medium speed signal or a high speed signal).

  Next, the operation of the power tool will be described mainly with reference to FIGS. 1, 2, 5, 6 and 8. When the operation is performed by rotating the drill 8, the operation section 26 of the operation moving member 22 may be pressed in the operation direction indicated by the arrow 64 (FIG. 2). Thus, the operation moving member 22 is slid in the operation direction indicated by the arrow 64, and the magnet mounting member 42 (and the first and second magnets 52, 54 together with the operation movement member 22) are integrally moved in the operation direction. Be moved.

  When the magnet mounting member 42 slides slightly in the operation direction in this way, as shown in FIG. 5, the sliding sleeve 40 moves over the initial position holding projection 78 in the operation direction by the action of the coil spring 66, as shown in FIG. . Thus, the protrusion 68 of the sliding sleeve 40 comes into contact with the action protrusion 70 on the housing body 34 side to prevent the movement thereof, and thereafter the operation moving member 22 and the magnet mounting member 42 Are relatively moved in the operation direction. Further, in this contact state, the pressing protrusion 72 of the sliding sleeve 40 presses the main switch 74 to be kept in the ON state, whereby the current from the battery 16 is supplied to the controller 18 and the like.

When the operation moving member 22 is further moved in the operation direction, the relative movement of the first and second magnets 52 and 54 with respect to the magnetic flux detecting means 56 increases, and the detection signal of the magnetic flux detecting means 56 changes. The relative movement of the first and second magnets 52 and 54 with respect to the magnetic flux detecting means 56 causes a rotation when the detection signal of the magnetic flux detecting means 56 becomes equal to or higher than the low speed value V1 (or the medium speed value V2 and the high speed value V3). The speed setting means 82 sets a low rotation speed (or a medium rotation speed, a high rotation speed), and based on the setting, the speed signal generation means 84 generates a low speed signal (or a medium speed signal, a high speed signal), and The driving means 86 drives the electric motor 10 to rotate at a low speed (or a medium speed or a high speed) based on the low speed signal (or a medium speed signal or a high speed signal). The rotation speed of the electric motor 10 (in other words, a working tool such as the drill 8) can be adjusted as required in accordance with the amount of operation of the operation moving member 22 by using one magnetic flux detecting means 56.

  In the above-described embodiment, the rotation speed of the electric motor 10 is configured to be able to be set to three stages of low speed, middle speed and high speed, but the rotation speed between the low speed value V1 and the high speed value V3 of the magnetic flux detecting means 56 is set. For example, by setting two speed values in the range of, for example, by setting a middle-low speed value V21 and a middle-high speed value V22, it is possible to set four stages of a low speed, a middle-low speed, a middle-high speed, and a high speed. By setting three or more values in this range, the degree of toxicity of the electric motor 10 can be set to five or more levels.

  As described above, the power tool according to the present invention is applied to the drill driver, but the present invention can be similarly applied to other power tools, for example, a grinder.

Reference Signs List 2 power tool main body 4 main body part 6 gripping part 10 electric motor 18 controller 20 trigger switch means 22 operation moving member 24 movement detecting part 34 housing main body 40 sliding sleeve 42 magnet mounting member 52, 54 magnet 56 magnetic flux detecting means 66 coil spring 80 Control means 82 Rotation speed setting means 84 Speed signal generation means

Claims (3)

An electric tool main body, an electric motor built in the electric tool main body, a work tool rotated by the electric motor, trigger switch means for changing a rotation speed of the electric motor, and A power tool having a rotation speed setting means for setting a rotation speed of the electric motor based on the detection signal;
The trigger switch means includes an operation moving member slidably mounted on the power tool main body, a magnet mounting portion mounted on the operation moving member, and the same pole facing the magnet mounting portion. and mounting the first and second magnets is, the first comprising 1 and a magnetic flux detecting means disposed in the power tool body side a between the second magnet, the rotational speed setting means, the flux detecting means It is configured to set the rotation speed of the electric motor based on a detection signal from
Further, the trigger switch means includes a housing main body that accommodates the first and second magnets and the magnet mounting member, and the operation moving member includes an operation unit and a movement shaft extending from the operation unit into the housing main body. A sliding sleeve is slidably supported by the moving shaft portion, and the magnet mounting member is attached to a distal end of the moving shaft portion, and the operation moving member and the sliding sleeve are connected to each other. A coil spring is interposed by fitting the moving shaft portion therebetween,
Further, the sliding sleeve is provided with a protrusion protruding radially outward, and the housing body is provided with an operation protrusion acting on the protrusion of the slide sleeve. Power tool. The housing main body is provided with an initial position holding projection corresponding to an initial position of the operation moving member, and the sliding sleeve side is provided with an initial position holding projection corresponding to the housing main body side. A contact portion is provided, and when the operation moving member is at the initial position, the contact portion on the sliding sleeve side contacts the initial position holding projection on the housing body side. The power tool according to claim 1. A pair of first guide protrusions extending in the sliding direction of the operation moving member are provided on the inner surface of the one-side wall of the housing main body, and extend in the sliding direction of the operation moving member on the inner surface of the other surface wall. A pair of second guide protrusions are provided, and the sliding sleeve and the magnet mounting member are slid along the pair of first guide protrusions and the pair of second guide protrusions. The power tool according to claim 1 .

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