JP2014028428A - Reciprocating tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reciprocating tool having excellent workability, a low-noise and low-vibration.SOLUTION: A reciprocating tool 1 comprises: a brushless motor 3; a plunger 52 being driven by the brushless motor 3 and reciprocating between a lower dead point and an upper dead point in which a tip tool 7 is attached to an end portion on a lower dead point side in a reciprocating direction; and control means for controlling rotation speed or a rotation angle of the brushless motor 3 on the basis of a position of the plunger 52. When the plunger 52 approaches the vicinity of the upper dead point or the lower dead point, control for decreasing the rotation speed of the brushless motor 3 is performed by the control means.

Description

  The present invention relates to a reciprocating tool, and more particularly to a portable reciprocating tool that cuts a workpiece by reciprocating movement of a tip tool such as a blade.

  Conventionally, a reciprocating tool such as a jigsaw has a structure in which a blade protrudes from a base that comes into contact with a workpiece, and the blade is moved up and down to cut the workpiece ( For example, Patent Document 1).

JP 2004-1363 A

  In a tip tool such as a jigsaw, when the tip tool such as a blade and the plunger to which the tip tool is mounted reciprocally move (up and down in the case of a jigsaw), both dead centers (top dead center and bottom dead center) The direction of motion is reversed by 180 °, but at both dead points (top dead center or bottom dead center), the direction of motion immediately before is abruptly reversed, causing vibration and noise.

  Also, when carrying reciprocating tools such as jigsaws, tip tools such as blades get in the way, so depending on the situation, the operator may grab the tip tool and push it into the base side (the side where the tip tool retracts) The switch for driving the tip tool (plunger) must be turned ON / OFF to stop the tip tool on one dead center side (the tip tool is the most retracted side, and in the case of a jigsaw, the top dead center side). Conversely, when replacing a tip tool such as a blade, replace the tip tool easily after placing it on the other dead center side (the side where the tip tool protrudes, in the case of a jigsaw, the bottom dead center side). It is necessary for the operator to grab the tip tool and pull it out of the base, or to turn on / off the switch that drives the tip tool to stop the tip tool on the other dead center side. Was inferior. Accordingly, an object of the present invention is to provide a reciprocating tool having good workability and low noise and vibration.

  In order to solve the above problems, the present invention provides a brushless motor, a plunger driven by the brushless motor to reciprocate between both dead centers, and a tip tool attached to one end in the reciprocating direction, and the plunger And a control means for controlling the rotation speed or rotation angle of the brushless motor based on the position of the reciprocating tool.

  According to such a configuration, the position and speed of the plunger can be easily controlled by the brushless motor.

  In the reciprocating tool having the above-described configuration, it is preferable that the reciprocating tool further includes detection means for detecting the position of the plunger.

  According to such a configuration, since the position of the plunger can be easily grasped, the position and speed of the plunger can be controlled more easily.

  The detection means is preferably a sensor that detects that the plunger has reached a specific position.

  According to such a configuration, the plunger position can be grasped more accurately with a simple configuration, and the position and speed of the plunger can be controlled with higher accuracy.

  The control means preferably decelerates the rotational speed of the brushless motor based on the position of the plunger.

  According to such a configuration, since the brushless motor is decelerated according to the position of the plunger, vibration and noise can be reduced.

  Further, it is preferable that the control means decelerates the brushless motor while the plunger is moving from one of the dead centers to the other dead center.

  According to such a configuration, since the brushless motor is decelerated before the plunger reaches the dead point, vibration and noise can be further reduced.

  Further, it is preferable that the control means decelerates the brushless motor when the plunger reaches a position before one of the dead centers.

  According to such a configuration, since the brushless motor is decelerated before the plunger moving direction is switched, vibration and noise when the moving direction is switched can be reduced.

  The control means decelerates the brushless motor when the plunger reaches a position before either one of the two dead centers, and then accelerates the brushless motor after passing through the one dead center. It is preferable.

  According to such a configuration, since the brushless motor is decelerated before the plunger moving direction is switched, vibration and noise when the moving direction is switched can be reduced, and the workpiece is cut by accelerating thereafter. Ability can be maintained.

  Deceleration position setting means for setting a deceleration position of the rotational speed of the brushless motor based on the position of the plunger, and the control means decelerates the brushless motor based on the deceleration position set by the deceleration position setting means. It is preferable to do.

  According to such a configuration, the deceleration position of the brushless motor can be set arbitrarily. Therefore, the deceleration position can be set at an arbitrary position where vibration and noise are most generated.

  The control means preferably maintains the brushless motor in a decelerated state until the position of the plunger passes one of the dead points.

  According to such a configuration, it is possible to reduce vibration and noise when the moving direction of the plunger, which is likely to generate vibration and noise, is switched.

  Preferably, the control means maintains the brushless motor in a decelerated state for a predetermined time after the brushless motor is decelerated.

  According to such a configuration, since the brushless motor continues to decelerate for a predetermined time, vibration and noise can be further reduced.

    A storage unit that stores a plurality of pieces of deceleration position information that can be set by the deceleration position setting unit, wherein the control unit decelerates the brushless motor based on the deceleration position information set by the deceleration position setting unit; It is preferable to calculate the time to be maintained in the storage means and store it in the storage means, and to decelerate the brushless motor until the deceleration continuation time stored in the storage means elapses.

  According to such a configuration, the deceleration start position can be set at a position with the largest vibration or noise. Moreover, since it decelerates while vibration and noise continue, vibration and noise can be reduced more.

  The control means calculates time until the first dead center reached after the brushless motor is decelerated based on the deceleration position information, stores the time in the storage means, and accelerates the brushless motor after passing through the dead center It is preferable.

  According to such a configuration, the vehicle can be decelerated in the vicinity of the dead center where vibration and noise are greatest, so that vibration and noise can be further reduced.

  A speed setting means for setting the rotation speed of the brushless motor; and a storage means for storing a plurality of pieces of deceleration position information that can be set by the deceleration position setting means. The control means is controlled by the deceleration position setting means. Based on information on the set deceleration position information and the rotational speed of the brushless motor that can be set by the speed setting means, a deceleration continuation time for maintaining the brushless motor in a decelerated state is calculated and stored in the storage means It is preferable.

  According to such a configuration, since the deceleration start position can be set according to the set speed of the brushless motor, vibration and noise can be reduced regardless of the set speed of the brushless motor.

  Memory that has speed setting means for setting the rotational speed of the brushless motor, and stores in advance a deceleration continuation time for maintaining the brushless motor in a decelerated state based on setting signals from the speed setting means and the deceleration position setting means Preferably, the control means decelerates the brushless motor in accordance with the deceleration continuation time stored in the storage means.

  According to such a configuration, since the deceleration time is stored in advance based on the rotational speed and deceleration position information of the brushless motor, vibration and noise can be reduced regardless of the set speed of the brushless motor, and the speed setting The calculation of the control means can be omitted each time.

  A storage unit for storing a predetermined rotation speed of the brushless motor, and the control unit is configured to store the rotation speed of the brushless motor set by the speed setting unit lower than the predetermined speed stored in the storage unit; The brushless motor is preferably controlled at a constant rotational speed regardless of the deceleration position signal from the deceleration position setting means.

  According to such a configuration, when the rotational speed of the brushless motor is slow, particularly when the brushless motor is at the minimum speed, the speed reduction control is not performed, so that the cutting ability of the workpiece can be maintained.

  It is preferable to have reset means for resetting the deceleration position of the brushless motor set by the deceleration position setting means.

  According to such a configuration, the deceleration position can be easily set at a position where vibration and noise are large.

  Preferably, the control means controls the brushless motor so that the plunger is stopped at one of the dead centers.

  According to such a configuration, when the plunger stops at the most protruding position, it becomes easy to attach and detach the tip tool attached to the plunger, and when the plunger stops at the most retracted position, when carrying the tool Plungers and tip tools are unlikely to interfere with transportation.

  It is preferable to have stop position switching means for switching the stop position of the plunger to either one of the dead centers.

  According to such a structure, since the stop position of a plunger can be selected according to a use, workability | operativity improves.

  It is preferable to have stop position setting means for setting the stop position of the plunger, and the control means controls the brushless motor to stop the plunger at a predetermined position set by the stop position setting means. .

  According to such a configuration, the workability is improved because the plunger can be stopped according to the application, for example, when the tool is transported or when the tip tool is attached or detached.

  The stop position setting means outputs a signal for stopping the plunger to one of the dead centers of the both dead points to the control means, and the control means outputs an output signal of the stop position setting means. Accordingly, it is preferable to control the brushless motor so as to stop the plunger.

  According to such a configuration, when the plunger stops at the protruding position, it becomes easy to attach and detach the tip tool attached to the plunger, and when the plunger stops at the retracted position, the plunger is moved when carrying the tool. And tip tools are unlikely to interfere with transportation. Conventionally, since the stop position cannot be specified, the mounting part is configured to be large so that the tip tool can be attached and detached at any position. However, since the stop position can be set, the mounting part can be configured to be small and the tool can be configured. Can be reduced in size and weight.

  The stop position setting means outputs a signal for switching the stop position of the plunger to the other dead center side of the two dead centers to the control means, and the control means is configured to output the signal according to the switching signal. It is preferable to control the brushless motor.

  According to such a structure, since the stop position of a plunger can be selected according to a use, workability | operativity improves.

  Rotational position detection means for detecting the rotational position of the brushless motor; storage means for preliminarily storing position data of the rotational position and the plunger position based on the position of the plunger corresponding to the rotational position of the brushless motor; And the control means calculates the position of the plunger based on the rotational position of the brushless motor detected by the rotational position detection means and the position data stored in the storage means. The reciprocating tool according to claim 1.

  According to such a configuration, the position of the plunger can be grasped from the rotational position information of the brushless motor. Therefore, it is not necessary to use detection means for detecting the position of the plunger.

  It is preferable to have storage reset means for resetting the position data of the rotational position of the brushless motor and the position of the plunger stored in the storage means.

  According to such a configuration, it is possible to reset when an error occurs in the positional relationship between the rotational position of the brushless motor and the position of the plunger.

  Preferably, the storage means has storage setting means for resetting position data of the rotational position of the brushless motor and the position of the plunger.

  According to such a configuration, since the positional relationship between the rotational position of the brushless motor and the position of the plunger is accurately stored, the brushless motor can be accurately controlled according to the position of the plunger.

  Moreover, you may provide the storage battery which supplies electric power to this brushless motor.

  According to such a configuration, the portability of the reciprocating tool is increased, so that workability can be increased.

Moreover, you may provide AC power supply which supplies electric power to this brushless motor.
According to such a structure, since work can be performed for a long time, workability can be increased.

  According to the reciprocating tool of the present invention, workability is good, and low noise and low vibration can be achieved.

Side surface sectional drawing of the reciprocating tool concerning embodiment of this invention. The figure which shows the drive part and braid | blade of the reciprocating tool concerning embodiment of this invention. The circuit diagram which shows the control apparatus of the reciprocating tool concerning embodiment of this invention. The graph which shows the relationship between the position of the plunger of the reciprocating tool concerning embodiment of this invention, and time. Side surface sectional drawing in the state which is the reciprocating tool concerning embodiment of this invention, and the braid | blade was located in the top dead center. The flowchart which concerns on the drive control of the plunger of the reciprocating tool concerning embodiment of this invention. The control block diagram of the reciprocating tool concerning embodiment of this invention. The control block diagram of the reciprocating tool concerning the example of a change of embodiment of this invention.

  Hereinafter, a reciprocating tool according to an embodiment of the present invention will be described with reference to FIGS. A jigsaw 1 which is a reciprocating tool such as a cutting tool shown in FIG. 1 mainly includes a housing 2, a motor 3, a base portion 4, a drive portion 5, a control device 6, and a blade 7 which is a tip tool. The tool is configured to advance a workpiece (not shown) with a blade 7. The direction in which the jigsaw 1 advances is defined as the forward direction in the cutting direction.

  The housing 2 is composed of a frame made of aluminum or the like, and a handle 21 is provided at a position that is an upper part of the rear end of the jigsaw 1 that is gripped by an operator. A trigger switch 22 that has a trigger 22 </ b> A that is operated by an operator and that controls power supply to the motor 3 is provided at the base portion of the handle 21. A storage battery 23 for supplying power to the motor 3, the control device 6, and the like is detachably provided at a position behind the handle 21 in the cutting direction. By using the storage battery 23 as a drive source for the motor 3 or the like, the portability of the jigsaw 1 can be improved and workability can be improved. The drive source for the motor 3 or the like may be an external commercial power supply (AC power supply) 90 (FIG. 8) instead of the storage battery 23. In this case, a DC voltage converter (converter) that converts AC power into DC power ) 80 (FIG. 8) is required. If the AC power supply 90 is used, work for a long time can be performed and workability can be improved. A position sensor 24 (for example, proximity) that detects a movement (between the top dead center and the bottom dead center) of a plunger 52 (described later) and outputs a signal in a portion located above the drive unit 5 in the housing 2. Sensor) is arranged. The position sensor 24 is preferably provided in the housing 2 on the longitudinal extension of the plunger 52 in order to detect the position of the plunger 52.

  The motor 3 is a DC brushless motor whose rotation speed and rotation angle can be finely controlled by the control device 6. The motor 3 is disposed in the housing 2 and has an output shaft 31 extending at one end in the front direction. A pinion gear 31 </ b> A is provided at the tip portion of the output shaft 31. A cooling fan 32 is provided on the base end side of the output shaft 31, and fan air is introduced into the housing 2 from a fan air inlet (not shown) formed in the housing 2 to cool the motor 3 and the control device 6. ing.

  The base portion 4 is formed in a substantially rectangular shape using aluminum or the like as a base material, and the surface facing the wood plate as a workpiece is defined as a facing surface 41A, and the longitudinal direction of the substantially rectangular shape matches the cutting direction. It carries the housing 2. Hereinafter, the vertical direction is defined with the direction from the housing 2 toward the base portion 4 being the downward direction and the opposite direction being the upward direction. A direction intersecting with the vertical direction and the cutting direction is defined as a horizontal direction. The base portion 4 and the housing 2 have a virtual axis that extends in the front-rear direction on the facing surface 41A and intersects the blade 7 as a swing axis, and the housing 2 extends in the left-right direction around the virtual axis with respect to the base portion 4. It is configured to be swingable.

  As shown in FIG. 1, the blade 7 is attached to a plunger 52, which will be described later, such that the blade portion faces the upper front side in the cutting direction and the back portion faces the rear side in the cutting direction.

  The drive unit 5 mainly includes a crank unit 51, a plunger 52, a transmission unit 53, and a roller holder 54. The crank portion 51 is mainly composed of a spur gear 51A, a pin 51B, and a spindle 51C. The spur gear 51 </ b> A meshes with the pinion gear 31 </ b> A and has a cam 51 </ b> D that engages with the transmission portion 53 at the base end portion. The pin 51B protrudes forward from the spur gear 51A in a state different from and parallel to the rotation shaft of the spur gear 51A. The spindle 51C rotatably supports the spur gear 51A and is fixed to the housing 2.

  The plunger 52 is configured in a substantially rod shape and is slidably supported in the housing 2 such that the longitudinal direction is the vertical direction. As shown in FIG. 2, a holding portion 52 </ b> A that holds the blade 7 is provided at the lower end portion of the plunger 52. In addition, a receiving portion 52B in which a groove 52b extending in the left-right direction is defined is provided in the central portion of the plunger 52, and a pin 51B is inserted into the groove 52b of the receiving portion 52B. Since the pin 51B is allowed to move in the left-right direction within the groove of the receiving portion 52B and is restricted from moving in the up-down direction, the receiving portion 52B can only move up and down according to the movement of the pin 51B. Therefore, the rotation of the pin 51B around the spindle 51C can be converted into the vertical movement of the plunger 52, and the plunger 52 moves up and down by a predetermined stroke amount S (FIG. 4).

  As shown in FIG. 1, the transmission portion 53 is supported by the housing 2 so as to be movable up and down, and is engaged with the cam 51D and driven to move up and down within the housing 2 by the cam 51D. The roller holder 54 includes a holder 54A, a roller 54B, and a shaft portion 54C. The holder 54A is disposed behind the blade 7 and supported by the housing 2 so as to be rotatable in a direction orthogonal to the left-right direction by a shaft portion 54C extending in the left-right direction. The upper part of the holder 54 </ b> A is in contact with the lower part of the transmission part 53. Therefore, when the transmission portion 53 moves up and down, the holder 54A also rotates counterclockwise and clockwise on the paper surface of FIG. The roller 54B is rotatably held at the lower end portion of the holder 54A and is disposed so as to contact the back portion of the blade 7.

  As shown in FIG. 1, the control device 6 is disposed behind the motor 3 in the housing 2, and is disposed in a fan wind passage generated by the rotation of the cooling fan 32. The control device 6 mainly includes a control circuit 61 and an FET drive circuit (inverter circuit) 62 described later.

  Here, the control device 6 will be described with reference to FIG. First, the motor 3 used in the present invention will be described. The motor 3 is a DC brushless motor as described above, and the rotor 3A is an internal magnet arrangement type in which N-pole and S-pole permanent magnets extending in the direction of the output shaft 31 are embedded, and the rotor 3A is arranged inside. A stator 3B having a cylindrical outer shape, and a stator winding (armature winding) 3C which is provided concentrically in the inner peripheral portion of the stator 3B and is composed of the three-phase windings U, V and W of the stator 3B. Consists of

  The stator winding 3C is wound in a slot of the stator 3B through an insulating layer (not shown) made of a resin material so as to surround the stator 3B. In the vicinity of the rotor 3A, Hall ICs 65, 66, and 67 serving as rotational position detecting means disposed at every 60 degrees in the rotational direction are disposed in order to detect the rotational position of the rotor 3A. The star-connected stator winding 3C is supplied with a current controlled by the FET drive circuit 62 based on the position detection signals of the Hall ICs 65, 66, and 67 in the current-carrying section having an electrical angle of 120 °.

  As shown in FIG. 7, the FET drive circuit 62 has six semiconductor switching elements 62A connected in a three-phase bridge format. The switching element 62A is composed of insulated gate bipolar transistors (IGBT) Q1 to Q6. Note that six FETs may be bridge-connected. The gates of the six switching elements 62A (Q1 to Q6) connected to the bridge are connected to the control signal output circuit 63 of the control circuit 61, and the collectors or emitters of the six switching elements 62A are star-connected. It is connected to the stator winding 3C (U, V, W) of the motor 3. As a result, the six switching elements 62 </ b> A perform a switching operation by the PWM drive signals (switching signals) H <b> 1 to H <b> 6 of the switching elements input from the control signal output circuit 63 to each switching element 62 </ b> A and are applied to the FET drive circuit 62. The DC voltage of the storage battery 23 is converted into three-phase (U-phase, V-phase, W-phase) drive voltages Vu, Vv, Vw, and three-phase AC power is supplied to the stator winding 3C.

  The control circuit 61 is provided to control the motor 3 and the like by outputting switching signals H1 to H6 to the FET drive circuit 62 via the control signal output circuit 63. The control circuit 61 includes a control / arithmetic unit 61A including a microcomputer for forming an output signal to the control signal output circuit 63 based on a processing program, control data, an input signal such as a motor position signal, and the like. The positional relationship between the rotor 3A and the stator winding 3C of the stator 3B is detected on the basis of the output signals from the Hall ICs 65, 66, 67 for detecting the rotational position of the rotor 3A in the vicinity of the rotor 3A. A rotor position detection circuit 68 for outputting the position information of the rotor 3A to the section 61A, and a rotation speed detection circuit 69 for detecting the rotation speed of the motor 3 from the time intervals of signals output from the Hall ICs 65, 66, 67 at regular intervals. A current detection circuit 70 that constantly detects the drive current of the motor 3 and outputs a detection signal to the control / calculation unit 61A; An applied voltage setting circuit 71 for setting the PWM duty of the switching signal corresponding to the output control signal generated by the trigger switch 22 based on the trigger pushing amount by the gas 22A, and speed setting means for setting the rotation speed of the motor 3 ( A speed instruction circuit 61E that outputs a set rotation speed signal to the control / arithmetic unit 61A in accordance with a signal from the volume VR) 72; a plunger position detection circuit 74 that detects the position of the plunger 52 based on a detection signal from the position sensor 24; , Mainly consists of.

  The control / arithmetic unit 61A controls the PWM duty ratio of the PWM drive signal of the switching element 62A based on output signals from the current detection circuit 70, the applied voltage setting circuit 71, the speed instruction circuit 61E, etc. The voltage (Vu, Vv, Vw) applied to the stator winding 3C is controlled. Further, based on the output signals from the rotor position detection circuit 68 and the rotation speed detection circuit 69, the switching element 62A is switched in a predetermined order so as to supply the applied voltage to the stator winding 3C in the predetermined order. Thus, the rotation of the motor 3 is controlled. Further, the position of the plunger 52 is calculated based on the output signal from the plunger position detection circuit 74, and the rotational speed (acceleration / deceleration or stop) of the motor 3 is controlled according to the plunger position. The control / calculation unit 61A includes a deceleration position setting means 76 for setting a deceleration position (α1 and α2 in FIG. 4) during the reciprocating movement of the plunger 52, and the plunger 52 when the trigger switch 22 is turned off. Stop position setting means 75 for setting the stop position is connected, and the control / calculation unit 61A detects the position of the plunger 52 detected by the position sensor 24 and the output signals of the stop position setting means 75 and the deceleration position setting means 76. The rotation speed and rotation angle of the motor 3 are controlled based on the above.

  The control circuit 61 is based on the output signal of the applied voltage setting circuit 71 corresponding to the trigger pressing amount of the trigger 22A of the trigger switch 22 and the motor rotation speed signal set by the speed setting means 72 and output from the speed instruction circuit 61E. The PWM duty of the switching signal of the switching element 62A is changed, the power supplied to the motor 3 is adjusted, and the rotational speed of the motor 3 is controlled. When the trigger pushing amount of the trigger 22A is the maximum, the motor rotation speed set by the speed setting means 72 is set equal.

  The control / arithmetic unit 61A includes a CPU for outputting a drive signal based on a processing program and each data, a ROM (storage means 64) for storing a processing program and control data for executing a control flow as described later, The microcomputer includes a RAM (storage means 64) for temporarily storing data, a timer 78 (FIG. 7) for counting time, and the like. The storage means 64 (RAM) stores the positional relationship between the position of the plunger 52 and the position of the motor 3 (rotor 3A), or the reciprocating time of the plunger 52 at a predetermined set speed or the time from the deceleration position to the dead point. Remember. The timer 78 counts the time from the predetermined position of the plunger 52 to the dead point.

  Further, the control / calculation unit 61A includes a position detection unit 61B, a speed control unit 61C, and a voltage control unit 61D as shown in FIG. The position detection unit 61B is connected to a rotor position detection circuit 68 (rotation speed detection circuit 69) that detects the rotation position (rotation speed) of the rotor 3A and a plunger position detection circuit 74 that detects the position of the plunger 52. The rotational position and rotational speed of the motor 3 and the position of the plunger 52 are calculated based on the signals from. As will be described later, terminal voltage detection means 77 may be connected instead of the rotor position detection circuit 68.

  The speed control unit 61C includes a motor setting speed signal from the speed instruction circuit 61E based on a preset signal from the speed setting unit 72, a motor rotation speed signal from the position detection unit 61B, a motor rotation position signal, and a plunger position. Based on the signal, a comparison is made as to whether or not the motor rotational speed has reached the motor set speed, and a signal relating to the rotational speed of the motor 3 is output to the voltage control unit 61D. The voltage control unit 61D outputs a drive control signal for the motor 3 to the FET drive circuit 62 via the control signal output circuit 63 based on the output signal of the speed control unit 61C.

  With the above configuration, when the jig 23 is connected to the housing 2 and the trigger switch 22 is operated, the motor 3 rotates and the plunger 52 moves up and down via the transmission portion 53 connected to the output shaft 31. The workpiece is cut by the attached blade 7. Specifically, when the trigger switch 22 is operated, a signal corresponding to the trigger push-in amount is output from the applied voltage setting circuit 71 to the control circuit 61. Based on this signal, the control / arithmetic unit 61A generates and outputs a switching signal of the switching element 62A to the FET drive circuit 62 via the control signal output circuit 63, and rotates the motor 3 at a rotation speed corresponding to the trigger pushing amount. The work of cutting the workpiece by is started. The maximum rotation speed of the motor 3 is the rotation speed set by the speed setting means 72.

  Thereafter, the control circuit 61 detects the rotational position and rotational speed of the rotor 3A via the rotor position detection circuit 68 and the rotational speed detection circuit 69 based on signals from the Hall ICs 65 to 67, and sets the motor speed according to the trigger push-in amount. Control to be. At the same time, the control circuit 61 calculates the position of the plunger 52 based on the outputs of the position sensor 24 and the plunger position detection circuit, and decelerates the plunger 52 when the plunger 52 reaches the plunger deceleration position set by the deceleration position setting means 76. . Thereafter, when the trigger switch 22 is turned off, the plunger 52 is stopped at the plunger stop position set by the stop position setting means 75, and the cutting operation by the jigsaw 1 is ended.

  As a method for detecting the rotational position of the rotor 3A, a terminal voltage (induced electromotive voltage) between the stator windings 3C of the motor 3 is detected instead of the Hall ICs 65, 66, 67 as shown in FIG. A sensorless method may be employed in which terminal voltage detecting means 77 is provided to detect the rotational position and rotational speed of the rotor 3A from the terminal voltage of the motor 3. The terminal voltage detecting means 77 can be configured to take out the terminal voltage (induced electromotive voltage) of the stator winding 3C as a logic signal through a filter.

  Next, deceleration control of the plunger 52 (motor 3) according to the present invention will be described. In the present invention, the position of the plunger 52 is calculated by the control circuit 61 based on the position information of the plunger 52 from the position sensor 24, the position information of the rotor 3A from the motor 3, or both position information. By controlling the rotation speed or rotation angle of the motor 3 when 52 reaches a predetermined position, vibration and noise are reduced and workability is improved.

  Hereinafter, control of the motor 3 when the deceleration start position of the motor 3 is set by the deceleration position setting means 76 so that the plunger 52 is in the vicinity of both dead points (before both dead points) will be described with reference to FIG. The control circuit 61 controls the switching of the switching element 62 </ b> A of the FET drive circuit 62 to control the rotation of the motor 3 to reciprocate the plunger 52, but the control / calculation unit 61 </ b> A always receives the plunger position information from the position sensor 24. When the position sensor 24 and the plunger position detection circuit 74 detect that the plunger 52 has reached the vicinity of both dead points during one reciprocation of the plunger 52, that is, the position before both dead points, the control / calculation unit 61A The switching element 62A is controlled so that the motor 3 rotating at the rotation speed (first speed) set by the speed setting means 72 is decelerated to a second speed slower than the first speed.

  Specifically, as shown in FIG. 4, when the plunger 52 is moving from the top dead center (t = 0) to the bottom dead center, the motor 3 is rotating at the first speed. Control / calculation unit 61A (position detection unit 61B) that the plunger 52 has reached (passed) the position near the bottom dead center that is the deceleration position set by the deceleration position setting means 76, for example, the position α1 that is the position before the bottom dead center. Based on the detection result, the control / calculation unit 61A (speed control unit 61C) outputs a signal for reducing the rotation speed of the motor 3 to the second speed to the switching element 62A of the FET drive circuit 62. As a result, the rotational speed of the motor 3 is decelerated from the set speed (first speed) to the deceleration speed (second speed) at the position α1. It is preferable to decelerate the motor 3 in the vicinity of both dead points where the moving direction of the plunger 52 that generates the most vibration and noise is switched. In particular, the inertia (kinetic energy) at the switching position of the moving direction by decelerating the position before the dead point. Is the most effective for suppressing vibration and noise.

  When the rotation speed of the motor 3 is always driven at the first speed and the plunger 52 is moved from the top dead center to the bottom dead center (graph L1: broken line), the motor 3 is moved at the position α1 at the position α1. When the rotational speed is decelerated from the first speed to the second speed (graph L2: solid line), it takes T + ΔT to move from the top dead center to the bottom dead center. Here, the second speed is set to 40% of the first speed, specifically, the movement amount ΔX of the plunger 52 per minute time Δt at the second speed is set to be 40% of the first speed. explain. Comparing the kinetic energy from the position α1 to the bottom dead center in the graph L1 and the graph L2, when the mass M is the same, the kinetic energy is proportional to the square of the velocity (kinetic energy = 0.5 × M × (ΔX / Δt) ^ 2)), the kinetic energy at the second speed is 0.5 × M × (0.4 × ΔX / Δt) ^ 2), and the graph L2 has 16% kinetic energy of the graph L1. At the bottom dead center, an impact is generated because the phase of the plunger 52 is reversed, but the graph L2 has only 16% kinetic energy with respect to the graph L1, so that the kinetic energy used for generating the impact is The impact when the phase of the plunger 52 is reversed can be suppressed.

  When the control / calculation unit 61 </ b> A detects that the plunger 52 has reached (passed) the bottom dead center position, the control / calculation unit 61 </ b> A (speed control unit 61 </ b> C) is connected to the switching element 62 </ b> A of the FET drive circuit 62 based on this detection result. Switching signals H1 to H6 corresponding to the first speed are output. Thereby, when passing through the bottom dead center position, the rotational speed of the motor 3 is accelerated from the second speed to the first speed. Note that the fact that the plunger 52 has reached the bottom dead center is that each of the decelerations from the position sensor 24 to the first dead center reached from the plurality of plunger deceleration positions that can be set by the deceleration position setting means 76. The time corresponding to the position can be stored in the storage means 64, and the time from the deceleration position to the dead point can be counted by the timer 78 and compared with the stored value. Further, the time stored in the storage means 64 is not limited to the time from the deceleration position to the dead point, but is the time between regions (predetermined regions within the stroke amount S) where vibration and noise are most likely to occur from past experience. But you can. The memory time does not need to be stored in advance from the deceleration position to the dead point. The timer 78 counts the time from the deceleration position to the dead point each time according to the signal from the position sensor 24. The stored value may be used in the next reciprocating motion.

  Furthermore, since the set speed (first speed) of the motor 3 can be set in a plurality of stages, the control / calculation unit 61A calculates the deceleration time based on the set speed and the deceleration setting position and stores it in the storage means 64. If the deceleration control of the motor 3 is performed based on the stored value, the motor 3 can be reliably controlled even if the jigsaw 1 is driven at any set speed, so that vibration and noise can be suppressed and workability can be improved. it can. Therefore, instead of decelerating the rotation speed of the motor 3 once and continuing to rotate at the deceleration speed (second speed), the motor 3 decelerates at a position where vibration and noise increase (near the bottom dead center) and passes through the bottom dead center. Since it accelerates later and rotates at a set speed (first speed), workability can be improved while suppressing vibration and noise.

  Similarly, when the plunger 52 moves from the bottom dead center to the top dead center, at the position α2 that is 180 ° out of phase with the position α1, that is, near the top dead center and at the position α2 near the top dead center, the motor By reducing the rotational speed 3 from the first speed to the second speed, it is possible to suppress the occurrence of impact (vibration or noise) at the top dead center. Then, after the plunger 52 passes through the top dead center, the control / calculation unit 61A controls the switching element 62A so as to accelerate the rotational speed of the motor 3 from the second speed to the first speed again. It is not necessary to match the distance from each dead point to the position before the bottom dead center α1 and the position before the top dead center α2, and the deceleration position setting means 76 sets the respective deceleration positions (α1, α2) to be different. You can also.

  In addition, when the set speed (first speed) of the motor 3 does not generate vibration or noise of the jigsaw 1 or generates little, it is possible to prevent the motor 3 from decelerating regardless of the setting of the deceleration position setting means 76. . For example, the rotational speed of the motor 3 that does not generate vibration or noise is stored in the storage unit 64 in advance, and when the set speed of the deceleration position setting unit 76 is the storage speed or lower than that, the deceleration position setting unit 76. It is possible to improve workability by controlling so as not to decelerate regardless of the setting.

  In addition, a reset switch is provided for resetting the deceleration position, resetting the deceleration time stored in the storage means 64, the position information of the plunger 52 and the motor 3, and the like each time the jigsaw 1 is used. In this case, the motor 3 can always be controlled with the latest information.

  As described above, when the plunger 52 reaches the predetermined position (α1, α2) by the deceleration position setting means 76, the rotational speed of the motor 3 is controlled to be decelerated, and the top dead center, the position before the bottom dead center α1, By reciprocating the bottom dead center, the position before the top dead center α2, the top dead center,..., A workpiece not shown is suppressed while suppressing the occurrence of impact at the top dead center position and the bottom dead center position. Since it can cut | disconnect, the workability | operativity at the time of use of the jigsaw 1 can be increased. As described above, when the first speed and the second speed are used together to suppress the occurrence of an impact, the period of the plunger 52 becomes longer by about 2ΔT compared to the case where the movement is always performed at the first speed. Since it is time, the amount of work is not significantly affected. When the work amount is affected, for example, the first speed at the time of no load is slightly increased in advance.

  Next, stop control of the plunger 52 (blade 7) after the cutting work by the jigsaw 1 is completed will be described. If the blade 7 protrudes from the base portion 4 at the end of the cutting operation, the blade 7 protruding when the jigsaw 1 is stored or transported becomes an obstacle. Therefore, as shown in FIG. 5, the control circuit 61 controls the rotation of the motor 3 so that the plunger 52 is stopped at the top dead center or a position near the top dead center.

  When the control circuit 61 detects that the drive signal of the motor 3 is not output from the trigger switch 22, that is, the cutting operation is completed, the control circuit 61 determines the position of the plunger 52 from the position signal of the plunger 52 from the position sensor 24. The switching signal of the switching element 62A is output to the FET drive circuit 62 while watching the above. When the control / calculation unit 61A detects that the plunger 52 has reached a top dead center or a position near the top dead center, for example, the top dead center or the position α2 in FIG. The unit 61A stops supplying the switching signal to the FET drive circuit 62, or forcibly stops the motor 3. Therefore, the plunger 52 can be stopped at the position shown in FIG. Further, the stop control of the motor 3 can be performed before reaching the set position, instead of performing the stop control of the motor 3 after reaching the set position.

  Also, as shown in FIG. 5, if the plunger 52 is stopped at the top dead center position or near the top dead center position, the base portion 4 or the like becomes obstructive when the blade 7 is attached or detached, and the workability is poor. Therefore, by providing stop position setting means 75 for switching the stop position of the plunger 52, after the plunger 52 is stopped at the top dead center position or near the top dead center position, the plunger 52 is moved to the bottom dead center position or the bottom dead center vicinity position ( The motor 3 can also be controlled to move to the bottom dead center or position α1) of FIG.

  Further, the information on the position of the plunger 52 and the stop position that can be set by the stop position setting means 75 (for example, the time until the stop position that can be set according to the plunger position) is stored in the storage means 64, and the trigger switch 22 is turned off. The control / calculation unit 61A detects the position of the plunger when it is detected, and the timer 78 counts the time from the detected plunger position to the stored set stop position, and the plunger 52 is moved to the desired stop position. You may make it stop.

  When the trigger 22A is pulled lightly once in the trigger switch 22 without providing the stop position setting means 75, that is, when the control / calculation unit 61A detects a signal from the trigger switch 22 once, the position detection unit 61B. Based on the position of the plunger 52 detected by the (position sensor 24, plunger position detection circuit 74), the FET drive circuit 62 or the like is controlled so that the plunger 52 moves to the bottom dead center position or a position near the bottom dead center. Good.

  The stop position setting means 75 not only switches the stop position of the plunger 52 from one of the top dead center side and the bottom dead center side to the other side, but also changes the stop position setting means 75 to the stop position of the plunger 52. It can also be used as a means for setting (for example, a dial or a switch).

  As described above, when the stop position setting means 75 is a dial, the dial is set to a desired stop position. The stop position setting means 75 is a switch. When there are a plurality of switches, the switch corresponding to the desired stop position is pressed. If there is only one switch, the desired stop position is set according to the number of times the switch is pressed. The control / calculation unit 61A controls the motor 3 based on the stop position signal and the position signal of the plunger 52 (the signal from the position sensor 24, the signal from the Hall ICs 65 to 67) to stop the plunger 52 at the set stop position. . If there is no particular need to set the stop position of the plunger 52, a signal for releasing the set position by adjusting a reset switch (not shown) or the stop position setting means 75 (in the case of a dial, set to a setting unnecessary position). Is output to the control / arithmetic unit 61A, the motor 3 can be controlled to stop at an arbitrary position when the trigger switch 22 is turned off.

  The stop position of the plunger 52 by the stop position setting means 75 does not need to be set before the cutting work before the trigger switch 22 is turned on, and can be set during the cutting work or after the cutting work is finished. Workability can be improved because it can be set whenever necessary.

  Hereinafter, in the jigsaw 1, the control at the time of work is demonstrated based on the flowchart of FIG. In this flowchart, the case where the position sensor 24 detects the position of the plunger 52 will be described. First, in S01, the speed of the motor 3 is set by the volume VR serving as the speed setting means 72. Then, the process proceeds to S02, and the control circuit 61 determines whether the trigger switch 22 is activated. Here, if the control circuit 61 determines that the trigger 22A is not operated by the operator and the trigger switch 22 is not operating (S02: N), the process returns to S01. If it is determined that the trigger 22A is operated by the operator and the trigger switch 22 is operated (S02: Y), the process proceeds to S03.

  In S03, based on the speed setting in the volume VR72, the control circuit 61 (control / calculation unit 61A including the speed control unit 61C in FIG. 4) sends the drive signal of the motor 3 (switching element of the FET drive circuit 62) to the FET drive circuit 62. The switching signals H1 to H6) are output to 62A, electric power is supplied from the storage battery 23 to the motor 3, and the motor 3 is rotated at a set speed. Next, proceeding to S04, whether or not the plunger 52 is detected by the position sensor 24, that is, whether or not the plunger 52 is located at a distance (near top dead center or near bottom dead center) that can be detected by the position sensor 24. To detect. The position sensor 24 may always detect the position of the plunger 52 as described above. If not detected (S04: N), the process returns to S03. When the plunger 52 is detected (S04: Y), the process proceeds to S05 and the position of the plunger 52 is specified by the control / calculation unit 61A (position detection unit 61B) and the stator windings of the Hall ICs 65 to 67 or the motor 3 are used. The motor rotation position is specified based on the terminal voltage between 3C.

  Next, proceeding to S06, based on the output signal of the position sensor 24, the control / calculation unit 61A (position detection unit 61B) determines whether or not the plunger 52 has reached the deceleration position of the motor 3 set by the deceleration position setting means 76. For example, it is detected whether the plunger 52 has passed either the position α1 before the bottom dead center or the position α2 before the top dead center. Here, information from the position where the plunger 52 is detected in the storage means 64 to the position α1 or position α2, top dead center or bottom dead center (time set according to the motor rotation speed, plunger position signal) , The motor position signal, etc.) is stored in advance, and the control / calculation unit 61A identifies the arrival at the predetermined position by comparing this stored value with the actual detection signal. When it is not detected that the position α1 or the position α2 has been passed (S06: N), the process returns to S03. When the control / calculation unit 61A detects that the position α1 or the position α2 has been passed (S06: Y), the process proceeds to S07, and the control / calculation unit 61A is set by the volume VR72 in S01. The switching signals H1 to H6 of the switching element 62A are output to the FET drive circuit 62 so that the rotational speed is lower than the set speed of the motor 3, thereby reducing the rotational speed of the motor 3. Here, the storage means 64 stores deceleration rotational speeds corresponding to a plurality of set speeds that can be set by the volume VR 72.

  Next, the process proceeds to S08, and the control / calculation unit 61A (position detection unit 61B) detects whether the plunger 52 has passed the top dead center or the bottom dead center based on the output signal from the position sensor 24. Further, it may be calculated from information stored in the storage means 64. If it is not detected that one of the top and bottom dead centers has been passed (S08: N), the process returns to S07 and the motor 3 continues to decelerate. If it is detected that one of the top and bottom dead centers has been passed (S08: Y), the process proceeds to S09, and based on the speed setting of the volume VR72, the control / calculation unit 61A (speed control unit 61C) performs S01. The switching signals H1 to H6 of the switching element 62A are output to the FET drive circuit 62 so as to achieve the rotation speed of the motor 3 set in (4), and the rotation speed of the motor 3 is accelerated.

  Next, proceeding to S10, the control circuit 61 determines whether or not the trigger 22A has been operated by the operator. If the trigger 22A is operated by the operator and the trigger switch 22 is operating (S10: Y), the process returns to S03 and loops from S03 to S10 again. When the operator stops the operation of the trigger 22A and the control circuit 61 determines that the trigger switch 22 is not operating (S10: N), the process proceeds to S11, and the control / calculation unit 61A (speed control unit 61C). Controls the output of the switching signals H1 to H6 to the FET drive circuit 62 to reduce the power supplied to the motor 3 from the storage battery 23, thereby decelerating the motor 3. In step S12, the position sensor 24 detects the position of the plunger 52. When it cannot detect (S12: N), it returns to S11, and when it can detect (S12: Y), it progresses to S13. It should be noted that the position sensor 24 may always detect the position of the plunger 52.

  In S13, based on the output signal of the position sensor 24, the control / calculation unit 61A (position detection unit 61B) determines whether the plunger 52 has reached the stop position of the motor 3 set by the stop position setting means 75, for example, the plunger It is detected whether 52 has moved to the top dead center or a position near the top dead center. If it is not possible to detect that the plunger 52 has moved to the top dead center or a position near the top dead center (S13: N), the process returns to S11. If it is detected that the plunger 52 has moved to the top dead center or a position near the top dead center (S13: Y), the process proceeds to S14, and the control / calculation unit 61A (speed control unit 61C) sends the FET drive circuit 62. The switching signals H1 to H6 of the switching element 62A are controlled, the motor 3 is braked, and the rotation of the output shaft 31 of the motor 3 is completely stopped, and the plunger 52 (blade 7) is positioned at or near the top dead center. And finish this control.

  In S13 and S14, when replacing the blade 7, the blade 7 (plunger 52) is preferably located at the bottom dead center. Therefore, by operating the stop position setting means 75, the stop position of the plunger 52 can be switched to the bottom dead center side, and the trigger 22A is pulled once and the plunger 52 is moved to the bottom dead center or the bottom dead center. It can also be moved to a nearby position. By disposing the blade 7 at this position, the blade 7 can be easily exchanged by operating the plunger 52 (holding portion 52A).

  Next, as a modified example of the present embodiment, the driving power source of the motor 3 is an AC power source, and the position of the plunger 52 is detected by detecting the rotational position and rotational speed of the motor 3 without using the position sensor 24. The method and method will be mainly described with reference to FIG.

  When performing speed control or stop position control of the plunger 52, it is necessary to control the motor 3 in accordance with the position of the plunger 52. Therefore, in the embodiment of the present invention, the position sensor 24 for detecting the position of the plunger 52 is provided, and the control / calculation unit 61A calculates the position of the plunger 52 based on the signal from the position sensor 24, and the motor 3 Is controlling. On the other hand, the rotational speed and rotational position of the motor 3 are controlled from the Hall ICs 65 to 67 for detecting the position of the rotor 3A of the motor 3 and the terminal voltage detection means 77 (FIG. 3) for detecting the voltage across the terminals of the stator winding 3C. It is done by the signal. Since the detection of the rotational position and rotational speed of the motor 3 (rotor 3A) by the Hall IC and terminal voltage is necessary when using a brushless motor, as shown in FIG. 8, the position of the plunger 52 is determined only from the motor rotational signal. Can be detected, it is not necessary to provide the position sensor 24, and the cost of sensor parts can be reduced.

  FIG. 8 differs from the circuit configuration of FIG. 7 in that the position sensor 24 and the plunger position detection circuit 74 are deleted, and the drive source of the motor 3 is an external commercial power supply (AC power supply) 90 instead of the storage battery 23. Yes. By using the AC power supply 90, a DC voltage conversion unit 80 for converting AC to DC, a pair of resistors 81 and 82 for detecting DC voltage, a DC voltage is detected, and a detection signal is sent to the control / calculation unit 61A. A voltage detection circuit 83 for output is added, and a display means 91 for displaying the operation setting state of the jigsaw 1 and a reference position setting means 92 for setting the reference position of the plunger 52 are added. The reference position setting unit 92 includes a switch or the like.

  When the position of the plunger 52 is calculated only with the position information of the motor 3, since the reciprocation of the plunger 52 (time 0 to 2T in FIG. 4) may not correspond to one rotation of the motor 3 (rotor 3A), It is necessary to align the position of the plunger 52 with the position of the motor 3. The setting of the plunger 52 position and the motor 3 position will be described below.

  When the jigsaw 1 is shipped from the factory (product assembly), the motor 3 is rotated using an external device to detect the rotational position of the rotor 3A and the position of the plunger 52. As an external device, the position may be detected based on the distance between the plunger 52 such as the position sensor 24 and the sensor, or a spring or the like may be connected to the plunger 52 and detected based on the pulling force of the spring. Various methods are conceivable. Further, the initial setting of the positional relationship between the plunger 52 and the motor 3 may be performed by the jigsaw 1 without using an external device.

  First, the plunger 52 is placed at a reference position, for example, top dead center, and the reference position setting means (switch) 92 is operated (turned on) to control the reference position (top dead center) of the plunger 52 to a control / calculation unit 61A (storage means 64). To recognize. The setting of the plunger 52 to the reference position may be performed by an operator or may be performed while measuring the position of the plunger 52 by an external device. The number of rotations of the motor 3 required for the plunger 52 to reciprocate once is stored in advance in the control / calculation unit 61A (storage means 64). Hereinafter, the case where the motor 3 rotates 10 times while the plunger 52 makes one reciprocation will be described as an example.

  When the motor 3 is rotated, the rotation position and rotation speed of the rotor 3A are detected by the Hall ICs 65 to 67. A pulse signal corresponding to the polarity (N pole, S pole) of the rotor 3A is output from the Hall IC. It is converted into a pulse signal that can be recognized by the control / calculation unit 61A by the rotor position detection circuit 68 and the rotation speed detection circuit 69 and input to the control / calculation unit 61A. In the case of FIG. 8, since the rotor 3A has a pair of N poles and S poles, the Hall IC outputs a signal corresponding to the change in polarity. Specifically, 2 pulses are output from each Hall IC per rotor rotation, and 6 pulses are output as a whole. Therefore, if the motor 3 rotates 10 times, 20 pulses are output from one Hall IC, and 60 pulses as a whole. This number of pulses is stored in advance in the control / calculation unit 61A. The plunger 52 is controlled based on the rotation information (pulse number) of the motor 3 during one reciprocation of the plunger 52 by storing the pulse number at the reference position set in the reference position setting means 92 so as to be zero. can do. In the case where the number of pulses input to the control / calculation unit 61A is increased and fine control is performed, a frequency dividing circuit for the number of pulses output from the Hall IC may be provided.

  At the time of factory shipment, the reference position setting unit 92 is operated to set the reference position of the plunger 52, and the number of pulses from the Hall IC when the plunger 52 makes one reciprocation from the reference position is stored in the storage unit 64. By operating the reference position setting means 92 during operation, the control / calculation unit 61A can recognize the position of the plunger 52 from the rotation information of the motor 3, that is, the pulse signal of the Hall IC. For example, when the total number of pulses from the Hall ICs 65 to 67 is 30, the control / calculation unit 61A compares the pulse information stored in the storage means 64 with the detected number of pulses (30 pulses), and the plunger 52 makes one reciprocation. It is possible to recognize that the number of pulses is half of that, that is, the plunger 52 is located at the dead point.

  When the plunger 52 reciprocates a plurality of times, the control / calculation unit 61A can recognize that the reference position has been reached when the number of pulses is an integral multiple of 60 pulses. For example, when the rotation speed of the motor 3 is set to 3000 rpm by the speed setting means 72, the motor rotates 50 times per second, so that the plunger 52 reciprocates 5 times. Since the number of pulses from the Hall ICs 65 to 67 is 60 in one round trip, it becomes 300 pulses in five round trips. The control / arithmetic unit 61A compares the number of pulses stored in the storage means 64 to determine the position of the plunger 52, and responds to signals from the deceleration position setting means 76 and the stop position setting means 75, for example, according to the number of pulses of the Hall IC. By comparing with the number of pulses from the Hall IC, the motor 3 is controlled so that the deceleration position and the stop position can be accurately recognized and the vehicle is decelerated and stopped at the set position. Therefore, the position of the plunger 52 can be calculated based only on the rotational position information of the motor 3 (rotor 3A) without providing the position sensor 24, and the position sensor 24 and the plunger position detection circuit 74 shown in FIG. 7 are omitted. can do.

  Here, a method for controlling the position of the plunger 52 based on the position information of the motor 3 will be described. The trigger switch 22 is turned on and the motor 3 is rotated. The control circuit 61 inputs the rotation position signal (pulse signal) of the motor 3 detected by the Hall ICs 65 to 67 via the rotor position detection circuit 68. The controller / arithmetic unit 61A calculates the position of the plunger 52 based on the detected motor position signal (number of pulses) and the motor position information (number of pulses) stored in the storage means 64 in advance. For example, when the detected number of pulses is 20, the control / calculation unit 61A recognizes that the plunger 52 has not reached the bottom dead center (number of pulses: 30), and at the predetermined position set by the deceleration position setting means 76 For example, it is confirmed whether or not the position before the top dead center or the position before the bottom dead center is reached. When the control / calculation unit 61A recognizes that the deceleration position has been set to a position corresponding to the number of pulses 20, the control / calculation unit 61A causes the FET drive circuit 62 to decelerate the rotation speed of the motor 3. Signals H1 to H6 are output. Subsequently, the control / calculation unit 61A detects the number of pulses from the Hall IC and, when recognizing that the number of pulses has reached 30, controls the motor 3 to accelerate. On the other hand, when the control circuit 61 detects that the trigger switch 22 is turned off, the control / calculation unit 61A determines a predetermined stop position set by the stop position setting means 75 from the number of pulses from the Hall IC, for example, the upper position. It is determined whether the number of pulses corresponding to the dead center position has been reached, and the motor 3 is controlled to stop the plunger 52. Therefore, even if the position sensor 24 of the plunger 52 is not provided, the position of the plunger 52 can be calculated from the position of the motor 3 by storing the positional relationship between the motor 3 and the plunger 52 in the storage unit 64 in advance.

  Further, by providing a memory resetting means for resetting the positional relationship between the motor 3 and the plunger 52 stored in the memory means 64 and a memory setting means for resetting the positional relationship between the motor 3 and the plunger 52, the old memory is stored. Data can be deleted and the latest data can always be stored. Therefore, highly accurate control can be performed. Note that the memory reset means and the memory setting means can also be used as the stop position setting means 75 and the deceleration position setting means 76. In the case of a dial, the memory reset means and the memory setting means are switched to the memory reset means when rotated continuously a predetermined number of times. In the case of a switch, it may be switched to the memory resetting means or the like according to the time it is pushed in, and then the means may be operated.

  When the positional relationship between the motor 3 and the plunger 52 is reset by the memory setting means, an external device used at the time of shipment from the factory may be used, but the jig can be set with the memory means 64 incorporated. Also good. In this case, it is necessary to provide the position sensor 24 and the plunger position detection circuit 74. When the memory setting means is operated, the control circuit 61 automatically rotates the motor 3 regardless of the state of the trigger switch 22. The control / calculation unit 61A reads the position information of the rotor 3A from the Hall ICs 65 to 67 or the terminal voltage of the stator winding 3C at every predetermined angle and stores it in the storage means 64. At the same time, the position information of the plunger 52 corresponding to the predetermined angle is read from the position sensor 24, and the positional relationship between the rotor 3 </ b> A and the plunger 52 is stored in the storage unit 64. The control circuit 61 stops the rotation of the motor 3 and ends the storing operation. As described above, if the positional relationship between the motor 3 and the plunger 52 is stored, the motor 3 can be controlled in accordance with the position of the plunger 52 even if the position sensor 24 fails, and workability can be improved. it can.

  Moreover, if the display means 91 (FIG. 8), such as a display and LED, is provided in the jigsaw 1, since it can memorize | store currently in operation, the setting rotational speed of the motor 3, a plunger position, etc., Workability can be further improved. Furthermore, if it is a display, it is possible to easily confirm the method of storage work and the situation of the deceleration position and the stop position.

  The reciprocating tool according to the present embodiment is not limited to the above-described embodiment, and various improvements and modifications can be made within the scope described in the claims. For example, one position sensor for grasping the position of the plunger is provided only on the top dead center side of the plunger. However, the position sensor is not limited to this and may be provided on the bottom dead center side. In this case, the position detection of the plunger is performed with higher accuracy. Various sensors can be applied instead of the proximity sensor.

  In this embodiment, a jigsaw that is a cutting tool has been described as a reciprocating tool. However, the present invention is not limited to this. be able to.

DESCRIPTION OF SYMBOLS 1 .. Jigsaw 2 .. Housing 3 .. Motor 3A .. Rotor 3B .. Stator 3C .. Stator winding 4 .... Base part 5 .... Drive part 6 .... Control device 7 ... Blade 21 ... Handle 22 ..Trigger switch 22A ..Trigger 23 ..Storage battery 24 ..Position sensor 31 ..Output shaft 31A ..Pinion gear 32 ..Cooling fan 41A ..Face surface 51 ..Crank part 51A. 51C ··· Spindle 51D · · Cam 52 · · Plunger 52A · · Holding portion 52B · · Receiving portion 52b · · Groove 53 · · Transmission portion 54 · · Roller holder 54A · · Holder 54B · · Roller 54C · · Shaft portion 61 ..Control circuit 61A ... Control / calculation unit 61B ... Position detection unit 61C ... Speed control unit 61D ... Voltage control unit 61E ... Speed indication circuit 2. FET drive circuit 62A Switching element 63 Control signal output circuit 64 Storage means 65-67 Hall IC 68 Rotor position detection circuit 69 Speed detection circuit 70 Current detection Circuit 71 .. Applied voltage setting circuit 72 .. Speed setting means (volume VR) 74.. Plunger position detection circuit 75 .. Stop position setting means 76 .. Deceleration position setting means 77 .. Terminal voltage detection means 78. 80 .. DC voltage converter 81, 82. Resistance 83. Voltage detection circuit 90. Power supply 91. Display means 92. Reference position setting means

  The present invention relates to a reciprocating tool, and more particularly to a portable reciprocating tool that cuts a workpiece by reciprocating movement of a tip tool such as a blade.

  Conventionally, a reciprocating tool such as a jigsaw has a structure in which a blade protrudes from a base that comes into contact with a workpiece, and the blade is moved up and down to cut the workpiece ( For example, Patent Document 1).

JP 2004-1363 A

  In a tip tool such as a jigsaw, when the tip tool such as a blade and the plunger to which the tip tool is mounted reciprocally move (up and down in the case of a jigsaw), both dead centers (top dead center and bottom dead center) The direction of motion is reversed by 180 °, but at both dead points (top dead center or bottom dead center), the direction of motion immediately before is abruptly reversed, causing vibration and noise.

  Also, when carrying reciprocating tools such as jigsaws, tip tools such as blades get in the way, so depending on the situation, the operator may grab the tip tool and push it into the base side (the side where the tip tool retracts) The switch for driving the tip tool (plunger) must be turned ON / OFF to stop the tip tool on one dead center side (the tip tool is the most retracted side, and in the case of a jigsaw, the top dead center side). Conversely, when replacing a tip tool such as a blade, replace the tip tool easily after placing it on the other dead center side (the side where the tip tool protrudes, in the case of a jigsaw, the bottom dead center side). It is necessary for the operator to grab the tip tool and pull it out of the base, or to turn on / off the switch that drives the tip tool to stop the tip tool on the other dead center side. Was inferior. Accordingly, an object of the present invention is to provide a reciprocating tool having good workability and low noise and vibration.

  In order to solve the above problems, the present invention provides a brushless motor, a plunger driven by the brushless motor to reciprocate between both dead centers, and a tip tool attached to one end in the reciprocating direction, and the plunger Control means for controlling the rotation speed or rotation angle of the brushless motor based on the position of the brushless motor, and the control means provides a reciprocating tool for controlling the brushless motor to stop the plunger at a predetermined position. .

  According to such a configuration, the plunger can be stopped at a predetermined position.

  It is preferable that the stop position of the plunger is on one of the dead centers.

  According to such a configuration, when the plunger stops at the most protruding position, it becomes easy to attach and detach the tip tool attached to the plunger, and when the plunger stops at the most retracted position, when carrying the tool Plungers and tip tools are unlikely to interfere with transportation.

  It is preferable to have stop position switching means for switching the stop position of the plunger to either one of the dead centers.

  According to such a structure, since the stop position of a plunger can be selected according to a use, workability | operativity improves.

  It is preferable to have stop position setting means for setting the stop position of the plunger, and the control means controls the brushless motor to stop the plunger at a predetermined position set by the stop position setting means. .

  According to such a configuration, the workability is improved because the plunger can be stopped according to the application, for example, when the tool is transported or when the tip tool is attached or detached.

  The stop position setting means outputs a signal for stopping the plunger to one of the dead centers of the both dead points to the control means, and the control means outputs an output signal of the stop position setting means. Accordingly, it is preferable to control the brushless motor so as to stop the plunger.

  According to such a configuration, when the plunger stops at the protruding position, it becomes easy to attach and detach the tip tool attached to the plunger, and when the plunger stops at the retracted position, the plunger is moved when carrying the tool. And tip tools are unlikely to interfere with transportation. Conventionally, since the stop position cannot be specified, the mounting part is configured to be large so that the tip tool can be attached and detached at any position. However, since the stop position can be set, the mounting part can be configured to be small and the tool can be configured. Can be reduced in size and weight.

  The stop position setting means outputs a signal for switching the stop position of the plunger to the other dead center side of the two dead centers to the control means, and the control means is configured to output the signal according to the switching signal. It is preferable to control the brushless motor.

  According to such a structure, since the stop position of a plunger can be selected according to a use, workability | operativity improves.

  Moreover, you may provide the storage battery which supplies electric power to this brushless motor.

  According to such a configuration, the portability of the reciprocating tool is increased, so that workability can be increased.

  Moreover, you may provide AC power supply which supplies electric power to this brushless motor.

  According to such a structure, since work can be performed for a long time, workability can be increased.

  According to the reciprocating tool of the present invention, workability can be improved.

Side surface sectional drawing of the reciprocating tool concerning embodiment of this invention. The figure which shows the drive part and braid | blade of the reciprocating tool concerning embodiment of this invention. The circuit diagram which shows the control apparatus of the reciprocating tool concerning embodiment of this invention. The graph which shows the relationship between the position of the plunger of the reciprocating tool concerning embodiment of this invention, and time. Side surface sectional drawing in the state which is the reciprocating tool concerning embodiment of this invention, and the braid | blade was located in the top dead center. The flowchart which concerns on the drive control of the plunger of the reciprocating tool concerning embodiment of this invention. The control block diagram of the reciprocating tool concerning embodiment of this invention. The control block diagram of the reciprocating tool concerning the example of a change of embodiment of this invention.

  Hereinafter, a reciprocating tool according to an embodiment of the present invention will be described with reference to FIGS. A jigsaw 1 which is a reciprocating tool such as a cutting tool shown in FIG. 1 mainly includes a housing 2, a motor 3, a base portion 4, a drive portion 5, a control device 6, and a blade 7 which is a tip tool. The tool is configured to advance a workpiece (not shown) with a blade 7. The direction in which the jigsaw 1 advances is defined as the forward direction in the cutting direction.

  The housing 2 is composed of a frame made of aluminum or the like, and a handle 21 is provided at a position that is an upper part of the rear end of the jigsaw 1 that is gripped by an operator. A trigger switch 22 that has a trigger 22 </ b> A that is operated by an operator and that controls power supply to the motor 3 is provided at the base portion of the handle 21. A storage battery 23 for supplying power to the motor 3, the control device 6, and the like is detachably provided at a position behind the handle 21 in the cutting direction. By using the storage battery 23 as a drive source for the motor 3 or the like, the portability of the jigsaw 1 can be improved and workability can be improved. The drive source for the motor 3 or the like may be an external commercial power supply (AC power supply) 90 (FIG. 8) instead of the storage battery 23. In this case, a DC voltage converter (converter) that converts AC power into DC power ) 80 (FIG. 8) is required. If the AC power supply 90 is used, work for a long time can be performed and workability can be improved. A position sensor 24 (for example, proximity) that detects a movement (between the top dead center and the bottom dead center) of a plunger 52 (described later) and outputs a signal in a portion located above the drive unit 5 in the housing 2. Sensor) is arranged. The position sensor 24 is preferably provided in the housing 2 on the longitudinal extension of the plunger 52 in order to detect the position of the plunger 52.

  The motor 3 is a DC brushless motor whose rotation speed and rotation angle can be finely controlled by the control device 6. The motor 3 is disposed in the housing 2 and has an output shaft 31 extending at one end in the front direction. A pinion gear 31 </ b> A is provided at the tip portion of the output shaft 31. A cooling fan 32 is provided on the base end side of the output shaft 31, and fan air is introduced into the housing 2 from a fan air inlet (not shown) formed in the housing 2 to cool the motor 3 and the control device 6. ing.

  The base portion 4 is formed in a substantially rectangular shape using aluminum or the like as a base material, and the surface facing the wood plate as a workpiece is defined as a facing surface 41A, and the longitudinal direction of the substantially rectangular shape matches the cutting direction. It carries the housing 2. Hereinafter, the vertical direction is defined with the direction from the housing 2 toward the base portion 4 being the downward direction and the opposite direction being the upward direction. A direction intersecting with the vertical direction and the cutting direction is defined as a horizontal direction. The base portion 4 and the housing 2 have a virtual axis that extends in the front-rear direction on the facing surface 41A and intersects the blade 7 as a swing axis, and the housing 2 extends in the left-right direction around the virtual axis with respect to the base portion 4. It is configured to be swingable.

  As shown in FIG. 1, the blade 7 is attached to a plunger 52, which will be described later, such that the blade portion faces the upper front side in the cutting direction and the back portion faces the rear side in the cutting direction.

  The drive unit 5 mainly includes a crank unit 51, a plunger 52, a transmission unit 53, and a roller holder 54. The crank portion 51 is mainly composed of a spur gear 51A, a pin 51B, and a spindle 51C. The spur gear 51 </ b> A meshes with the pinion gear 31 </ b> A and has a cam 51 </ b> D that engages with the transmission portion 53 at the base end portion. The pin 51B protrudes forward from the spur gear 51A in a state different from and parallel to the rotation shaft of the spur gear 51A. The spindle 51C rotatably supports the spur gear 51A and is fixed to the housing 2.

  The plunger 52 is configured in a substantially rod shape and is slidably supported in the housing 2 such that the longitudinal direction is the vertical direction. As shown in FIG. 2, a holding portion 52 </ b> A that holds the blade 7 is provided at the lower end portion of the plunger 52. In addition, a receiving portion 52B in which a groove 52b extending in the left-right direction is defined is provided in the central portion of the plunger 52, and a pin 51B is inserted into the groove 52b of the receiving portion 52B. Since the pin 51B is allowed to move in the left-right direction within the groove of the receiving portion 52B and is restricted from moving in the up-down direction, the receiving portion 52B can only move up and down according to the movement of the pin 51B. Therefore, the rotation of the pin 51B around the spindle 51C can be converted into the vertical movement of the plunger 52, and the plunger 52 moves up and down by a predetermined stroke amount S (FIG. 4).

  As shown in FIG. 1, the transmission portion 53 is supported by the housing 2 so as to be movable up and down, and is engaged with the cam 51D and driven to move up and down within the housing 2 by the cam 51D. The roller holder 54 includes a holder 54A, a roller 54B, and a shaft portion 54C. The holder 54A is disposed behind the blade 7 and supported by the housing 2 so as to be rotatable in a direction orthogonal to the left-right direction by a shaft portion 54C extending in the left-right direction. The upper part of the holder 54 </ b> A is in contact with the lower part of the transmission part 53. Therefore, when the transmission portion 53 moves up and down, the holder 54A also rotates counterclockwise and clockwise on the paper surface of FIG. The roller 54B is rotatably held at the lower end portion of the holder 54A and is disposed so as to contact the back portion of the blade 7.

  As shown in FIG. 1, the control device 6 is disposed behind the motor 3 in the housing 2, and is disposed in a fan wind passage generated by the rotation of the cooling fan 32. The control device 6 mainly includes a control circuit 61 and an FET drive circuit (inverter circuit) 62 described later.

  Here, the control device 6 will be described with reference to FIG. First, the motor 3 used in the present invention will be described. The motor 3 is a DC brushless motor as described above, and the rotor 3A is an internal magnet arrangement type in which N-pole and S-pole permanent magnets extending in the direction of the output shaft 31 are embedded, and the rotor 3A is arranged inside. A stator 3B having a cylindrical outer shape, and a stator winding (armature winding) 3C which is provided concentrically in the inner peripheral portion of the stator 3B and is composed of the three-phase windings U, V and W of the stator 3B. Consists of

  The stator winding 3C is wound in a slot of the stator 3B through an insulating layer (not shown) made of a resin material so as to surround the stator 3B. In the vicinity of the rotor 3A, Hall ICs 65, 66, and 67 serving as rotational position detecting means disposed at every 60 degrees in the rotational direction are disposed in order to detect the rotational position of the rotor 3A. The star-connected stator winding 3C is supplied with a current controlled by the FET drive circuit 62 based on the position detection signals of the Hall ICs 65, 66, and 67 in the current-carrying section having an electrical angle of 120 °.

  As shown in FIG. 7, the FET drive circuit 62 has six semiconductor switching elements 62A connected in a three-phase bridge format. The switching element 62A is composed of insulated gate bipolar transistors (IGBT) Q1 to Q6. Note that six FETs may be bridge-connected. The gates of the six switching elements 62A (Q1 to Q6) connected to the bridge are connected to the control signal output circuit 63 of the control circuit 61, and the collectors or emitters of the six switching elements 62A are star-connected. It is connected to the stator winding 3C (U, V, W) of the motor 3. As a result, the six switching elements 62 </ b> A perform a switching operation by the PWM drive signals (switching signals) H <b> 1 to H <b> 6 of the switching elements input from the control signal output circuit 63 to each switching element 62 </ b> A and are applied to the FET drive circuit 62. The DC voltage of the storage battery 23 is converted into three-phase (U-phase, V-phase, W-phase) drive voltages Vu, Vv, Vw, and three-phase AC power is supplied to the stator winding 3C.

  The control circuit 61 is provided to control the motor 3 and the like by outputting switching signals H1 to H6 to the FET drive circuit 62 via the control signal output circuit 63. The control circuit 61 includes a control / arithmetic unit 61A including a microcomputer for forming an output signal to the control signal output circuit 63 based on a processing program, control data, an input signal such as a motor position signal, and the like. The positional relationship between the rotor 3A and the stator winding 3C of the stator 3B is detected on the basis of the output signals from the Hall ICs 65, 66, 67 for detecting the rotational position of the rotor 3A in the vicinity of the rotor 3A. A rotor position detection circuit 68 for outputting the position information of the rotor 3A to the section 61A, and a rotation speed detection circuit 69 for detecting the rotation speed of the motor 3 from the time intervals of signals output from the Hall ICs 65, 66, 67 at regular intervals. A current detection circuit 70 that constantly detects the drive current of the motor 3 and outputs a detection signal to the control / calculation unit 61A; An applied voltage setting circuit 71 for setting the PWM duty of the switching signal corresponding to the output control signal generated by the trigger switch 22 based on the trigger pushing amount by the gas 22A, and speed setting means for setting the rotation speed of the motor 3 ( A speed instruction circuit 61E that outputs a set rotation speed signal to the control / arithmetic unit 61A in accordance with a signal from the volume VR) 72; a plunger position detection circuit 74 that detects the position of the plunger 52 based on a detection signal from the position sensor 24; , Mainly consists of.

  The control / arithmetic unit 61A controls the PWM duty ratio of the PWM drive signal of the switching element 62A based on output signals from the current detection circuit 70, the applied voltage setting circuit 71, the speed instruction circuit 61E, etc. The voltage (Vu, Vv, Vw) applied to the stator winding 3C is controlled. Further, based on the output signals from the rotor position detection circuit 68 and the rotation speed detection circuit 69, the switching element 62A is switched in a predetermined order so as to supply the applied voltage to the stator winding 3C in the predetermined order. Thus, the rotation of the motor 3 is controlled. Further, the position of the plunger 52 is calculated based on the output signal from the plunger position detection circuit 74, and the rotational speed (acceleration / deceleration or stop) of the motor 3 is controlled according to the plunger position. The control / calculation unit 61A includes a deceleration position setting means 76 for setting a deceleration position (α1 and α2 in FIG. 4) during the reciprocating movement of the plunger 52, and the plunger 52 when the trigger switch 22 is turned off. Stop position setting means 75 for setting the stop position is connected, and the control / calculation unit 61A detects the position of the plunger 52 detected by the position sensor 24 and the output signals of the stop position setting means 75 and the deceleration position setting means 76. The rotation speed and rotation angle of the motor 3 are controlled based on the above.

  The control circuit 61 is based on the output signal of the applied voltage setting circuit 71 corresponding to the trigger pressing amount of the trigger 22A of the trigger switch 22 and the motor rotation speed signal set by the speed setting means 72 and output from the speed instruction circuit 61E. The PWM duty of the switching signal of the switching element 62A is changed, the power supplied to the motor 3 is adjusted, and the rotational speed of the motor 3 is controlled. When the trigger pushing amount of the trigger 22A is the maximum, the motor rotation speed set by the speed setting means 72 is set equal.

  The control / arithmetic unit 61A includes a CPU for outputting a drive signal based on a processing program and each data, a ROM (storage means 64) for storing a processing program and control data for executing a control flow as described later, The microcomputer includes a RAM (storage means 64) for temporarily storing data, a timer 78 (FIG. 7) for counting time, and the like. The storage means 64 (RAM) stores the positional relationship between the position of the plunger 52 and the position of the motor 3 (rotor 3A), or the reciprocating time of the plunger 52 at a predetermined set speed or the time from the deceleration position to the dead point. Remember. The timer 78 counts the time from the predetermined position of the plunger 52 to the dead point.

  Further, the control / calculation unit 61A includes a position detection unit 61B, a speed control unit 61C, and a voltage control unit 61D as shown in FIG. The position detection unit 61B is connected to a rotor position detection circuit 68 (rotation speed detection circuit 69) that detects the rotation position (rotation speed) of the rotor 3A and a plunger position detection circuit 74 that detects the position of the plunger 52. The rotational position and rotational speed of the motor 3 and the position of the plunger 52 are calculated based on the signals from. As will be described later, terminal voltage detection means 77 may be connected instead of the rotor position detection circuit 68.

  The speed control unit 61C includes a motor setting speed signal from the speed instruction circuit 61E based on a preset signal from the speed setting unit 72, a motor rotation speed signal from the position detection unit 61B, a motor rotation position signal, and a plunger position. Based on the signal, a comparison is made as to whether or not the motor rotational speed has reached the motor set speed, and a signal relating to the rotational speed of the motor 3 is output to the voltage control unit 61D. The voltage control unit 61D outputs a drive control signal for the motor 3 to the FET drive circuit 62 via the control signal output circuit 63 based on the output signal of the speed control unit 61C.

  With the above configuration, when the jig 23 is connected to the housing 2 and the trigger switch 22 is operated, the motor 3 rotates and the plunger 52 moves up and down via the transmission portion 53 connected to the output shaft 31. The workpiece is cut by the attached blade 7. Specifically, when the trigger switch 22 is operated, a signal corresponding to the trigger push-in amount is output from the applied voltage setting circuit 71 to the control circuit 61. Based on this signal, the control / arithmetic unit 61A generates and outputs a switching signal of the switching element 62A to the FET drive circuit 62 via the control signal output circuit 63, and rotates the motor 3 at a rotation speed corresponding to the trigger pushing amount. The work of cutting the workpiece by is started. The maximum rotation speed of the motor 3 is the rotation speed set by the speed setting means 72.

  Thereafter, the control circuit 61 detects the rotational position and rotational speed of the rotor 3A via the rotor position detection circuit 68 and the rotational speed detection circuit 69 based on signals from the Hall ICs 65 to 67, and sets the motor speed according to the trigger push-in amount. Control to be. At the same time, the control circuit 61 calculates the position of the plunger 52 based on the outputs of the position sensor 24 and the plunger position detection circuit, and decelerates the plunger 52 when the plunger 52 reaches the plunger deceleration position set by the deceleration position setting means 76. . Thereafter, when the trigger switch 22 is turned off, the plunger 52 is stopped at the plunger stop position set by the stop position setting means 75, and the cutting operation by the jigsaw 1 is ended.

  As a method for detecting the rotational position of the rotor 3A, a terminal voltage (induced electromotive voltage) between the stator windings 3C of the motor 3 is detected instead of the Hall ICs 65, 66, 67 as shown in FIG. A sensorless method may be employed in which terminal voltage detecting means 77 is provided to detect the rotational position and rotational speed of the rotor 3A from the terminal voltage of the motor 3. The terminal voltage detecting means 77 can be configured to take out the terminal voltage (induced electromotive voltage) of the stator winding 3C as a logic signal through a filter.

  Next, deceleration control of the plunger 52 (motor 3) according to the present invention will be described. In the present invention, the position of the plunger 52 is calculated by the control circuit 61 based on the position information of the plunger 52 from the position sensor 24, the position information of the rotor 3A from the motor 3, or both position information. By controlling the rotation speed or rotation angle of the motor 3 when 52 reaches a predetermined position, vibration and noise are reduced and workability is improved.

  Hereinafter, control of the motor 3 when the deceleration start position of the motor 3 is set by the deceleration position setting means 76 so that the plunger 52 is in the vicinity of both dead points (before both dead points) will be described with reference to FIG. The control circuit 61 controls the switching of the switching element 62 </ b> A of the FET drive circuit 62 to control the rotation of the motor 3 to reciprocate the plunger 52, but the control / calculation unit 61 </ b> A always receives the plunger position information from the position sensor 24. When the position sensor 24 and the plunger position detection circuit 74 detect that the plunger 52 has reached the vicinity of both dead points during one reciprocation of the plunger 52, that is, the position before both dead points, the control / calculation unit 61A The switching element 62A is controlled so that the motor 3 rotating at the rotation speed (first speed) set by the speed setting means 72 is decelerated to a second speed slower than the first speed.

  Specifically, as shown in FIG. 4, when the plunger 52 is moving from the top dead center (t = 0) to the bottom dead center, the motor 3 is rotating at the first speed. Control / calculation unit 61A (position detection unit 61B) that the plunger 52 has reached (passed) the position near the bottom dead center that is the deceleration position set by the deceleration position setting means 76, for example, the position α1 that is the position before the bottom dead center. Based on the detection result, the control / calculation unit 61A (speed control unit 61C) outputs a signal for reducing the rotation speed of the motor 3 to the second speed to the switching element 62A of the FET drive circuit 62. As a result, the rotational speed of the motor 3 is decelerated from the set speed (first speed) to the deceleration speed (second speed) at the position α1. It is preferable to decelerate the motor 3 in the vicinity of both dead points where the moving direction of the plunger 52 that generates the most vibration and noise is switched. In particular, the inertia (kinetic energy) at the switching position of the moving direction by decelerating the position before the dead point. Is the most effective for suppressing vibration and noise.

  When the rotation speed of the motor 3 is always driven at the first speed and the plunger 52 is moved from the top dead center to the bottom dead center (graph L1: broken line), the motor 3 is moved at the position α1 at the position α1. When the rotational speed is decelerated from the first speed to the second speed (graph L2: solid line), it takes T + ΔT to move from the top dead center to the bottom dead center. Here, the second speed is set to 40% of the first speed, specifically, the movement amount ΔX of the plunger 52 per minute time Δt at the second speed is set to be 40% of the first speed. explain. Comparing the kinetic energy from the position α1 to the bottom dead center in the graph L1 and the graph L2, when the mass M is the same, the kinetic energy is proportional to the square of the velocity (kinetic energy = 0.5 × M × (ΔX / Δt) ^ 2)), the kinetic energy at the second speed is 0.5 × M × (0.4 × ΔX / Δt) ^ 2), and the graph L2 has 16% kinetic energy of the graph L1. At the bottom dead center, an impact is generated because the phase of the plunger 52 is reversed, but the graph L2 has only 16% kinetic energy with respect to the graph L1, so that the kinetic energy used for generating the impact is The impact when the phase of the plunger 52 is reversed can be suppressed.

  When the control / calculation unit 61 </ b> A detects that the plunger 52 has reached (passed) the bottom dead center position, the control / calculation unit 61 </ b> A (speed control unit 61 </ b> C) is connected to the switching element 62 </ b> A of the FET drive circuit 62 based on this detection result. Switching signals H1 to H6 corresponding to the first speed are output. Thereby, when passing through the bottom dead center position, the rotational speed of the motor 3 is accelerated from the second speed to the first speed. Note that the fact that the plunger 52 has reached the bottom dead center is that each of the decelerations from the position sensor 24 to the first dead center reached from the plurality of plunger deceleration positions that can be set by the deceleration position setting means 76. The time corresponding to the position can be stored in the storage means 64, and the time from the deceleration position to the dead point can be counted by the timer 78 and compared with the stored value. Further, the time stored in the storage means 64 is not limited to the time from the deceleration position to the dead point, but is the time between regions (predetermined regions within the stroke amount S) where vibration and noise are most likely to occur from past experience. But you can. The memory time does not need to be stored in advance from the deceleration position to the dead point. The timer 78 counts the time from the deceleration position to the dead point each time according to the signal from the position sensor 24. The stored value may be used in the next reciprocating motion.

  Furthermore, since the set speed (first speed) of the motor 3 can be set in a plurality of stages, the control / calculation unit 61A calculates the deceleration time based on the set speed and the deceleration setting position and stores it in the storage means 64. If the deceleration control of the motor 3 is performed based on the stored value, the motor 3 can be reliably controlled even if the jigsaw 1 is driven at any set speed, so that vibration and noise can be suppressed and workability can be improved. it can. Therefore, instead of decelerating the rotation speed of the motor 3 once and continuing to rotate at the deceleration speed (second speed), the motor 3 decelerates at a position where vibration and noise increase (near the bottom dead center) and passes through the bottom dead center. Since it accelerates later and rotates at a set speed (first speed), workability can be improved while suppressing vibration and noise.

  Similarly, when the plunger 52 moves from the bottom dead center to the top dead center, at the position α2 that is 180 ° out of phase with the position α1, that is, near the top dead center and at the position α2 near the top dead center, the motor By reducing the rotational speed 3 from the first speed to the second speed, it is possible to suppress the occurrence of impact (vibration or noise) at the top dead center. Then, after the plunger 52 passes through the top dead center, the control / calculation unit 61A controls the switching element 62A so as to accelerate the rotational speed of the motor 3 from the second speed to the first speed again. It is not necessary to match the distance from each dead point to the position before the bottom dead center α1 and the position before the top dead center α2, and the deceleration position setting means 76 sets the respective deceleration positions (α1, α2) to be different. You can also.

  In addition, when the set speed (first speed) of the motor 3 does not generate vibration or noise of the jigsaw 1 or generates little, it is possible to prevent the motor 3 from decelerating regardless of the setting of the deceleration position setting means 76. . For example, the rotational speed of the motor 3 that does not generate vibration or noise is stored in the storage unit 64 in advance, and when the set speed of the deceleration position setting unit 76 is the storage speed or lower than that, the deceleration position setting unit 76. It is possible to improve workability by controlling so as not to decelerate regardless of the setting.

  In addition, a reset switch is provided for resetting the deceleration position, resetting the deceleration time stored in the storage means 64, the position information of the plunger 52 and the motor 3, and the like each time the jigsaw 1 is used. In this case, the motor 3 can always be controlled with the latest information.

  As described above, when the plunger 52 reaches the predetermined position (α1, α2) by the deceleration position setting means 76, the rotational speed of the motor 3 is controlled to be decelerated, and the top dead center, the position before the bottom dead center α1, By reciprocating the bottom dead center, the position before the top dead center α2, the top dead center,..., A workpiece not shown is suppressed while suppressing the occurrence of impact at the top dead center position and the bottom dead center position. Since it can cut | disconnect, the workability | operativity at the time of use of the jigsaw 1 can be increased. As described above, when the first speed and the second speed are used together to suppress the occurrence of an impact, the period of the plunger 52 becomes longer by about 2ΔT compared to the case where the movement is always performed at the first speed. Since it is time, the amount of work is not significantly affected. When the work amount is affected, for example, the first speed at the time of no load is slightly increased in advance.

  Next, stop control of the plunger 52 (blade 7) after the cutting work by the jigsaw 1 is completed will be described. If the blade 7 protrudes from the base portion 4 at the end of the cutting operation, the blade 7 protruding when the jigsaw 1 is stored or transported becomes an obstacle. Therefore, as shown in FIG. 5, the control circuit 61 controls the rotation of the motor 3 so that the plunger 52 is stopped at the top dead center or a position near the top dead center.

  When the control circuit 61 detects that the drive signal of the motor 3 is not output from the trigger switch 22, that is, the cutting operation is completed, the control circuit 61 determines the position of the plunger 52 from the position signal of the plunger 52 from the position sensor 24. The switching signal of the switching element 62A is output to the FET drive circuit 62 while watching the above. When the control / calculation unit 61A detects that the plunger 52 has reached a top dead center or a position near the top dead center, for example, the top dead center or the position α2 in FIG. The unit 61A stops supplying the switching signal to the FET drive circuit 62, or forcibly stops the motor 3. Therefore, the plunger 52 can be stopped at the position shown in FIG. Further, the stop control of the motor 3 can be performed before reaching the set position, instead of performing the stop control of the motor 3 after reaching the set position.

  Also, as shown in FIG. 5, if the plunger 52 is stopped at the top dead center position or near the top dead center position, the base portion 4 or the like becomes obstructive when the blade 7 is attached or detached, and the workability is poor. Therefore, by providing stop position setting means 75 for switching the stop position of the plunger 52, after the plunger 52 is stopped at the top dead center position or near the top dead center position, the plunger 52 is moved to the bottom dead center position or the bottom dead center vicinity position ( The motor 3 can also be controlled to move to the bottom dead center or position α1) of FIG.

  Further, the information on the position of the plunger 52 and the stop position that can be set by the stop position setting means 75 (for example, the time until the stop position that can be set according to the plunger position) is stored in the storage means 64, and the trigger switch 22 is turned off. The control / calculation unit 61A detects the position of the plunger when it is detected, and the timer 78 counts the time from the detected plunger position to the stored set stop position, and the plunger 52 is moved to the desired stop position. You may make it stop.

  When the trigger 22A is pulled lightly once in the trigger switch 22 without providing the stop position setting means 75, that is, when the control / calculation unit 61A detects a signal from the trigger switch 22 once, the position detection unit 61B. Based on the position of the plunger 52 detected by the (position sensor 24, plunger position detection circuit 74), the FET drive circuit 62 or the like is controlled so that the plunger 52 moves to the bottom dead center position or a position near the bottom dead center. Good.

  The stop position setting means 75 not only switches the stop position of the plunger 52 from one of the top dead center side and the bottom dead center side to the other side, but also changes the stop position setting means 75 to the stop position of the plunger 52. It can also be used as a means for setting (for example, a dial or a switch).

  As described above, when the stop position setting means 75 is a dial, the dial is set to a desired stop position. The stop position setting means 75 is a switch. When there are a plurality of switches, the switch corresponding to the desired stop position is pressed. If there is only one switch, the desired stop position is set according to the number of times the switch is pressed. The control / calculation unit 61A controls the motor 3 based on the stop position signal and the position signal of the plunger 52 (the signal from the position sensor 24, the signal from the Hall ICs 65 to 67) to stop the plunger 52 at the set stop position. . If there is no particular need to set the stop position of the plunger 52, a signal for releasing the set position by adjusting a reset switch (not shown) or the stop position setting means 75 (in the case of a dial, set to a setting unnecessary position). Is output to the control / arithmetic unit 61A, the motor 3 can be controlled to stop at an arbitrary position when the trigger switch 22 is turned off.

  The stop position of the plunger 52 by the stop position setting means 75 does not need to be set before the cutting work before the trigger switch 22 is turned on, and can be set during the cutting work or after the cutting work is finished. Workability can be improved because it can be set whenever necessary.

  Hereinafter, in the jigsaw 1, the control at the time of work is demonstrated based on the flowchart of FIG. In this flowchart, the case where the position sensor 24 detects the position of the plunger 52 will be described. First, in S01, the speed of the motor 3 is set by the volume VR serving as the speed setting means 72. Then, the process proceeds to S02, and the control circuit 61 determines whether the trigger switch 22 is activated. Here, if the control circuit 61 determines that the trigger 22A is not operated by the operator and the trigger switch 22 is not operating (S02: N), the process returns to S01. If it is determined that the trigger 22A is operated by the operator and the trigger switch 22 is operated (S02: Y), the process proceeds to S03.

  In S03, based on the speed setting in the volume VR72, the control circuit 61 (control / calculation unit 61A including the speed control unit 61C in FIG. 4) sends the drive signal of the motor 3 (switching element of the FET drive circuit 62) to the FET drive circuit 62. The switching signals H1 to H6) are output to 62A, electric power is supplied from the storage battery 23 to the motor 3, and the motor 3 is rotated at a set speed. Next, proceeding to S04, whether or not the plunger 52 is detected by the position sensor 24, that is, whether or not the plunger 52 is located at a distance (near top dead center or near bottom dead center) that can be detected by the position sensor 24. To detect. The position sensor 24 may always detect the position of the plunger 52 as described above. If not detected (S04: N), the process returns to S03. When the plunger 52 is detected (S04: Y), the process proceeds to S05 and the position of the plunger 52 is specified by the control / calculation unit 61A (position detection unit 61B) and the stator windings of the Hall ICs 65 to 67 or the motor 3 are used. The motor rotation position is specified based on the terminal voltage between 3C.

  Next, proceeding to S06, based on the output signal of the position sensor 24, the control / calculation unit 61A (position detection unit 61B) determines whether or not the plunger 52 has reached the deceleration position of the motor 3 set by the deceleration position setting means 76. For example, it is detected whether the plunger 52 has passed either the position α1 before the bottom dead center or the position α2 before the top dead center. Here, information from the position where the plunger 52 is detected in the storage means 64 to the position α1 or position α2, top dead center or bottom dead center (time set according to the motor rotation speed, plunger position signal) , The motor position signal, etc.) is stored in advance, and the control / calculation unit 61A identifies the arrival at the predetermined position by comparing this stored value with the actual detection signal. When it is not detected that the position α1 or the position α2 has been passed (S06: N), the process returns to S03. When the control / calculation unit 61A detects that the position α1 or the position α2 has been passed (S06: Y), the process proceeds to S07, and the control / calculation unit 61A is set by the volume VR72 in S01. The switching signals H1 to H6 of the switching element 62A are output to the FET drive circuit 62 so that the rotational speed is lower than the set speed of the motor 3, thereby reducing the rotational speed of the motor 3. Here, the storage means 64 stores deceleration rotational speeds corresponding to a plurality of set speeds that can be set by the volume VR 72.

  Next, the process proceeds to S08, and the control / calculation unit 61A (position detection unit 61B) detects whether the plunger 52 has passed the top dead center or the bottom dead center based on the output signal from the position sensor 24. Further, it may be calculated from information stored in the storage means 64. If it is not detected that one of the top and bottom dead centers has been passed (S08: N), the process returns to S07 and the motor 3 continues to decelerate. If it is detected that one of the top and bottom dead centers has been passed (S08: Y), the process proceeds to S09, and based on the speed setting of the volume VR72, the control / calculation unit 61A (speed control unit 61C) performs S01. The switching signals H1 to H6 of the switching element 62A are output to the FET drive circuit 62 so as to achieve the rotation speed of the motor 3 set in (4), and the rotation speed of the motor 3 is accelerated.

  Next, proceeding to S10, the control circuit 61 determines whether or not the trigger 22A has been operated by the operator. If the trigger 22A is operated by the operator and the trigger switch 22 is operating (S10: Y), the process returns to S03 and loops from S03 to S10 again. When the operator stops the operation of the trigger 22A and the control circuit 61 determines that the trigger switch 22 is not operating (S10: N), the process proceeds to S11, and the control / calculation unit 61A (speed control unit 61C). Controls the output of the switching signals H1 to H6 to the FET drive circuit 62 to reduce the power supplied to the motor 3 from the storage battery 23, thereby decelerating the motor 3. In step S12, the position sensor 24 detects the position of the plunger 52. When it cannot detect (S12: N), it returns to S11, and when it can detect (S12: Y), it progresses to S13. It should be noted that the position sensor 24 may always detect the position of the plunger 52.

  In S13, based on the output signal of the position sensor 24, the control / calculation unit 61A (position detection unit 61B) determines whether the plunger 52 has reached the stop position of the motor 3 set by the stop position setting means 75, for example, the plunger It is detected whether 52 has moved to the top dead center or a position near the top dead center. If it is not possible to detect that the plunger 52 has moved to the top dead center or a position near the top dead center (S13: N), the process returns to S11. If it is detected that the plunger 52 has moved to the top dead center or a position near the top dead center (S13: Y), the process proceeds to S14, and the control / calculation unit 61A (speed control unit 61C) sends the FET drive circuit 62. The switching signals H1 to H6 of the switching element 62A are controlled, the motor 3 is braked, and the rotation of the output shaft 31 of the motor 3 is completely stopped, and the plunger 52 (blade 7) is positioned at or near the top dead center. And finish this control.

  In S13 and S14, when replacing the blade 7, the blade 7 (plunger 52) is preferably located at the bottom dead center. Therefore, by operating the stop position setting means 75, the stop position of the plunger 52 can be switched to the bottom dead center side, and the trigger 22A is pulled once and the plunger 52 is moved to the bottom dead center or the bottom dead center. It can also be moved to a nearby position. By disposing the blade 7 at this position, the blade 7 can be easily exchanged by operating the plunger 52 (holding portion 52A).

  Next, as a modified example of the present embodiment, the driving power source of the motor 3 is an AC power source, and the position of the plunger 52 is detected by detecting the rotational position and rotational speed of the motor 3 without using the position sensor 24. The method and method will be mainly described with reference to FIG.

  When performing speed control or stop position control of the plunger 52, it is necessary to control the motor 3 in accordance with the position of the plunger 52. Therefore, in the embodiment of the present invention, the position sensor 24 for detecting the position of the plunger 52 is provided, and the control / calculation unit 61A calculates the position of the plunger 52 based on the signal from the position sensor 24, and the motor 3 Is controlling. On the other hand, the rotational speed and rotational position of the motor 3 are controlled from the Hall ICs 65 to 67 for detecting the position of the rotor 3A of the motor 3 and the terminal voltage detection means 77 (FIG. 3) for detecting the voltage across the terminals of the stator winding 3C. It is done by the signal. Since the detection of the rotational position and rotational speed of the motor 3 (rotor 3A) by the Hall IC and terminal voltage is necessary when using a brushless motor, as shown in FIG. 8, the position of the plunger 52 is determined only from the motor rotational signal. Can be detected, it is not necessary to provide the position sensor 24, and the cost of sensor parts can be reduced.

  FIG. 8 differs from the circuit configuration of FIG. 7 in that the position sensor 24 and the plunger position detection circuit 74 are deleted, and the drive source of the motor 3 is an external commercial power supply (AC power supply) 90 instead of the storage battery 23. Yes. By using the AC power supply 90, a DC voltage conversion unit 80 for converting AC to DC, a pair of resistors 81 and 82 for detecting DC voltage, a DC voltage is detected, and a detection signal is sent to the control / calculation unit 61A. A voltage detection circuit 83 for output is added, and a display means 91 for displaying the operation setting state of the jigsaw 1 and a reference position setting means 92 for setting the reference position of the plunger 52 are added. The reference position setting unit 92 includes a switch or the like.

  When the position of the plunger 52 is calculated only with the position information of the motor 3, since the reciprocation of the plunger 52 (time 0 to 2T in FIG. 4) may not correspond to one rotation of the motor 3 (rotor 3A), It is necessary to align the position of the plunger 52 with the position of the motor 3. The setting of the plunger 52 position and the motor 3 position will be described below.

  When the jigsaw 1 is shipped from the factory (product assembly), the motor 3 is rotated using an external device to detect the rotational position of the rotor 3A and the position of the plunger 52. As an external device, the position may be detected based on the distance between the plunger 52 such as the position sensor 24 and the sensor, or a spring or the like may be connected to the plunger 52 and detected based on the pulling force of the spring. Various methods are conceivable. Further, the initial setting of the positional relationship between the plunger 52 and the motor 3 may be performed by the jigsaw 1 without using an external device.

  First, the plunger 52 is placed at a reference position, for example, top dead center, and the reference position setting means (switch) 92 is operated (turned on) to control the reference position (top dead center) of the plunger 52 to a control / calculation unit 61A (storage means 64). To recognize. The setting of the plunger 52 to the reference position may be performed by an operator or may be performed while measuring the position of the plunger 52 by an external device. The number of rotations of the motor 3 required for the plunger 52 to reciprocate once is stored in advance in the control / calculation unit 61A (storage means 64). Hereinafter, the case where the motor 3 rotates 10 times while the plunger 52 makes one reciprocation will be described as an example.

  When the motor 3 is rotated, the rotation position and rotation speed of the rotor 3A are detected by the Hall ICs 65 to 67. A pulse signal corresponding to the polarity (N pole, S pole) of the rotor 3A is output from the Hall IC. It is converted into a pulse signal that can be recognized by the control / calculation unit 61A by the rotor position detection circuit 68 and the rotation speed detection circuit 69 and input to the control / calculation unit 61A. In the case of FIG. 8, since the rotor 3A has a pair of N poles and S poles, the Hall IC outputs a signal corresponding to the change in polarity. Specifically, 2 pulses are output from each Hall IC per rotor rotation, and 6 pulses are output as a whole. Therefore, if the motor 3 rotates 10 times, 20 pulses are output from one Hall IC, and 60 pulses as a whole. This number of pulses is stored in advance in the control / calculation unit 61A. The plunger 52 is controlled based on the rotation information (pulse number) of the motor 3 during one reciprocation of the plunger 52 by storing the pulse number at the reference position set in the reference position setting means 92 so as to be zero. can do. In the case where the number of pulses input to the control / calculation unit 61A is increased and fine control is performed, a frequency dividing circuit for the number of pulses output from the Hall IC may be provided.

  At the time of factory shipment, the reference position setting unit 92 is operated to set the reference position of the plunger 52, and the number of pulses from the Hall IC when the plunger 52 makes one reciprocation from the reference position is stored in the storage unit 64. By operating the reference position setting means 92 during operation, the control / calculation unit 61A can recognize the position of the plunger 52 from the rotation information of the motor 3, that is, the pulse signal of the Hall IC. For example, when the total number of pulses from the Hall ICs 65 to 67 is 30, the control / calculation unit 61A compares the pulse information stored in the storage means 64 with the detected number of pulses (30 pulses), and the plunger 52 makes one reciprocation. It is possible to recognize that the number of pulses is half of that, that is, the plunger 52 is located at the dead point.

  When the plunger 52 reciprocates a plurality of times, the control / calculation unit 61A can recognize that the reference position has been reached when the number of pulses is an integral multiple of 60 pulses. For example, when the rotation speed of the motor 3 is set to 3000 rpm by the speed setting means 72, the motor rotates 50 times per second, so that the plunger 52 reciprocates 5 times. Since the number of pulses from the Hall ICs 65 to 67 is 60 in one round trip, it becomes 300 pulses in five round trips. The control / arithmetic unit 61A compares the number of pulses stored in the storage means 64 to determine the position of the plunger 52, and responds to signals from the deceleration position setting means 76 and the stop position setting means 75, for example, according to the number of pulses of the Hall IC. By comparing with the number of pulses from the Hall IC, the motor 3 is controlled so that the deceleration position and the stop position can be accurately recognized and the vehicle is decelerated and stopped at the set position. Therefore, the position of the plunger 52 can be calculated based only on the rotational position information of the motor 3 (rotor 3A) without providing the position sensor 24, and the position sensor 24 and the plunger position detection circuit 74 shown in FIG. 7 are omitted. can do.

  Here, a method for controlling the position of the plunger 52 based on the position information of the motor 3 will be described. The trigger switch 22 is turned on and the motor 3 is rotated. The control circuit 61 inputs the rotation position signal (pulse signal) of the motor 3 detected by the Hall ICs 65 to 67 via the rotor position detection circuit 68. The controller / arithmetic unit 61A calculates the position of the plunger 52 based on the detected motor position signal (number of pulses) and the motor position information (number of pulses) stored in the storage means 64 in advance. For example, when the detected number of pulses is 20, the control / calculation unit 61A recognizes that the plunger 52 has not reached the bottom dead center (number of pulses: 30), and at the predetermined position set by the deceleration position setting means 76 For example, it is confirmed whether or not the position before the top dead center or the position before the bottom dead center is reached. When the control / calculation unit 61A recognizes that the deceleration position has been set to a position corresponding to the number of pulses 20, the control / calculation unit 61A causes the FET drive circuit 62 to decelerate the rotation speed of the motor 3. Signals H1 to H6 are output. Subsequently, the control / calculation unit 61A detects the number of pulses from the Hall IC and, when recognizing that the number of pulses has reached 30, controls the motor 3 to accelerate. On the other hand, when the control circuit 61 detects that the trigger switch 22 is turned off, the control / calculation unit 61A determines a predetermined stop position set by the stop position setting means 75 from the number of pulses from the Hall IC, for example, the upper position. It is determined whether the number of pulses corresponding to the dead center position has been reached, and the motor 3 is controlled to stop the plunger 52. Therefore, even if the position sensor 24 of the plunger 52 is not provided, the position of the plunger 52 can be calculated from the position of the motor 3 by storing the positional relationship between the motor 3 and the plunger 52 in the storage unit 64 in advance.

  Further, by providing a memory resetting means for resetting the positional relationship between the motor 3 and the plunger 52 stored in the memory means 64 and a memory setting means for resetting the positional relationship between the motor 3 and the plunger 52, the old memory is stored. Data can be deleted and the latest data can always be stored. Therefore, highly accurate control can be performed. Note that the memory reset means and the memory setting means can also be used as the stop position setting means 75 and the deceleration position setting means 76. In the case of a dial, the memory reset means and the memory setting means are switched to the memory reset means when rotated continuously a predetermined number of times. In the case of a switch, it may be switched to the memory resetting means or the like according to the time it is pushed in, and then the means may be operated.

  When the positional relationship between the motor 3 and the plunger 52 is reset by the memory setting means, an external device used at the time of shipment from the factory may be used, but the jig can be set with the memory means 64 incorporated. Also good. In this case, it is necessary to provide the position sensor 24 and the plunger position detection circuit 74. When the memory setting means is operated, the control circuit 61 automatically rotates the motor 3 regardless of the state of the trigger switch 22. The control / calculation unit 61A reads the position information of the rotor 3A from the Hall ICs 65 to 67 or the terminal voltage of the stator winding 3C at every predetermined angle and stores it in the storage means 64. At the same time, the position information of the plunger 52 corresponding to the predetermined angle is read from the position sensor 24, and the positional relationship between the rotor 3 </ b> A and the plunger 52 is stored in the storage unit 64. The control circuit 61 stops the rotation of the motor 3 and ends the storing operation. As described above, if the positional relationship between the motor 3 and the plunger 52 is stored, the motor 3 can be controlled in accordance with the position of the plunger 52 even if the position sensor 24 fails, and workability can be improved. it can.

  Moreover, if the display means 91 (FIG. 8), such as a display and LED, is provided in the jigsaw 1, since it can memorize | store currently in operation, the setting rotational speed of the motor 3, a plunger position, etc., Workability can be further improved. Furthermore, if it is a display, it is possible to easily confirm the method of storage work and the situation of the deceleration position and the stop position.

  The reciprocating tool according to the present embodiment is not limited to the above-described embodiment, and various improvements and modifications can be made within the scope described in the claims. For example, one position sensor for grasping the position of the plunger is provided only on the top dead center side of the plunger. However, the position sensor is not limited to this and may be provided on the bottom dead center side. In this case, the position detection of the plunger is performed with higher accuracy. Various sensors can be applied instead of the proximity sensor.

  In this embodiment, a jigsaw that is a cutting tool has been described as a reciprocating tool. However, the present invention is not limited to this. be able to.

1 ・ ・ Jigsaw 2 ・ ・ Housing 3 ・ ・ Motor 3A ・ ・ Rotor 3B ・ ・ Stator
3C ・ ・ Stator winding 4 ・ ・ Base part 5 ・ ・ Drive part 6 ・ ・ Control device
7. ・ Blade 21 ・ ・ Handle 22 ・ ・ Trigger switch 22A ・ ・ Trigger
23 .... Storage battery 24 ... Position sensor 31 ... Output shaft 31A ... Pinion gear
32 ... Cooling fan 41A ... Opposite surface 51 ... Crank part 51A ... Spur gear
51B ··· Pin 51C · · Spindle 51D · · Cam 52 · · Plunger
52A ·· Holding portion 52B ·· Receiving portion 52b ·· Groove 53 ·· Transmission portion
54 ·· Roller holder 54A · · Holder 54B · · Roller 54C · · Shaft
61..Control circuit 61A..Control / calculation unit 61B..Position detection unit
61C ... Speed control unit 61D ... Voltage control unit 61E ... Speed indication circuit
62..FET drive circuit 62A..Switching element 63..Control signal output circuit
64..Storage means 65-67..Hall IC 68..Rotor position detection circuit
69..Rotation speed detection circuit 70..Current detection circuit 71..Applied voltage setting circuit
72 .. Speed setting means (volume VR) 74.. Plunger position detection circuit
75 .. Stop position setting means 76 .. Deceleration position setting means 77 .. Terminal voltage detection means
78..Timer 80..DC voltage converter 81, 82..resistance 83..voltage detection circuit
90..Power supply 91..Display means 92..Reference position setting means

Claims (26)

A brushless motor,
A plunger that is driven by the brushless motor to reciprocate between both dead points, and has a tip tool attached to one end side in the reciprocating direction;
A reciprocating tool comprising: control means for controlling a rotation speed or a rotation angle of the brushless motor based on a position of the plunger.   The reciprocating tool according to claim 1, further comprising detection means for detecting the position of the plunger.   The reciprocating tool according to claim 2, wherein the detecting means is a sensor that detects that the plunger has reached a specific position.   The reciprocating tool according to claim 1, wherein the control means decelerates the rotational speed of the brushless motor based on the position of the plunger.   The reciprocating tool according to claim 4, wherein the control means decelerates the brushless motor while the plunger moves from one of the two dead centers to the other dead center.   6. The reciprocating tool according to claim 5, wherein the control means decelerates the brushless motor when the plunger reaches a position before one of the two dead centers.   The control means decelerates the brushless motor when the plunger reaches a position before either one of the two dead centers, and then accelerates the brushless motor after passing through the one dead center. The reciprocating tool according to claim 6. A deceleration position setting means for setting a deceleration position of the rotational speed of the brushless motor based on the position of the plunger;
The reciprocating tool according to claim 4, wherein the control means decelerates the brushless motor based on the deceleration position set by the deceleration position setting means.   The reciprocating tool according to claim 8, wherein the control means maintains the brushless motor in a decelerated state until the position of the plunger passes through one of the dead points.   The reciprocating tool according to claim 8, wherein the control means maintains the brushless motor in a decelerated state for a predetermined time after the brushless motor is decelerated. Storage means for storing a plurality of deceleration position information settable by the deceleration position setting means;
The control means calculates a time for maintaining the brushless motor in a decelerated state based on the deceleration position information set by the deceleration position setting means, stores it in the storage means as a deceleration continuation time, and stores it in the storage means. The reciprocating tool according to claim 8, wherein the brushless motor is maintained in a decelerated state until the stored deceleration continuation time elapses.   The control means calculates time until the first dead center reached after the brushless motor is decelerated based on the deceleration position information, stores the time in the storage means, and accelerates the brushless motor after passing through the dead center The reciprocating tool according to claim 11. A speed setting means for setting the rotation speed of the brushless motor; and a storage means for storing a plurality of pieces of deceleration position information that can be set by the deceleration position setting means. The control means is set by the deceleration position setting means. Calculating a deceleration continuation time for maintaining the brushless motor in a decelerated state based on information on the decelerated position information and the rotational speed of the brushless motor that can be set by the speed setting means, and storing it in the storage means The reciprocating tool according to claim 8. Having speed setting means for setting the rotational speed of the brushless motor;
Storage means for preliminarily storing a deceleration continuation time for maintaining the brushless motor in a decelerated state based on setting signals from the speed setting means and the deceleration position setting means;
The reciprocating tool according to claim 8, wherein the control means decelerates the brushless motor in accordance with the deceleration continuation time stored in the storage means. Storage means for storing a predetermined rotational speed of the brushless motor;
When the rotational speed of the brushless motor set by the speed setting means is lower than the predetermined speed stored in the storage means, the control means is responsive to the brushless motor regardless of the deceleration position signal from the deceleration position setting means. The reciprocating tool according to claim 8, wherein the reciprocating tool is controlled at a constant rotational speed.   The reciprocating tool according to claim 8, further comprising reset means for resetting a deceleration position of the brushless motor set by the deceleration position setting means.   2. The reciprocating tool according to claim 1, wherein the control unit controls the brushless motor so as to stop the plunger toward one of the dead centers.   The reciprocating tool according to claim 17, further comprising stop position switching means for switching the stop position of the plunger to either one of the dead centers. Having stop position setting means for setting the stop position of the plunger;
2. The reciprocating tool according to claim 1, wherein the control means controls the brushless motor so as to stop the plunger at a predetermined position set by the stop position setting means. The stop position setting means outputs a signal for stopping the plunger to either one of the dead centers, to the control means,
The reciprocating tool according to claim 18, wherein the control means controls the brushless motor to stop the plunger in accordance with an output signal of the stop position setting means. The stop position setting means outputs a signal for switching the stop position of the plunger to the other dead center side of the two dead centers to the control means,
The reciprocating tool according to claim 20, wherein the control means controls the brushless motor in accordance with the switching signal. Rotational position detecting means for detecting the rotational position of the brushless motor;
Based on the position of the plunger corresponding to the rotational position of the brushless motor, the storage means stores in advance position data of the rotational position and the plunger position;
The control means calculates the position of the plunger based on the rotation position of the brushless motor detected by the rotation position detection means and the position data stored in the storage means. The reciprocating tool described.   The reciprocating tool according to claim 22, further comprising storage reset means for resetting position data of the rotational position of the brushless motor and the position of the plunger stored in the storage means.   The reciprocating tool according to claim 23, wherein the storage means has storage setting means for resetting the position data of the rotational position of the brushless motor and the position of the plunger.   The reciprocating tool according to any one of claims 1 to 24, further comprising a storage battery for supplying electric power to the brushless motor.   The reciprocating tool according to any one of claims 1 to 24, further comprising an AC power source for supplying electric power to the brushless motor.

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