WO2017051892A1 - Grinder - Google Patents

Abstract

The grinder according to one aspect of the present invention is equipped with: a housing in which a motor is housed and from which a tip tool mounting spindle rotationally driven by the motor protrudes; a handle unit which is for a user to grip and is fixed to the housing; one or more first operating units which are provided to the housing; one or more second operating units which are provided to the handle unit; and a control unit which starts the driving of the motor when at least one of the first operating units and at least one of the second operating units are operated at the same time.

Description

Grinder Cross-reference of related applications

This international application claims priority based on Japanese Patent Application No. 2015-188011 filed with the Japan Patent Office on September 25, 2015. The entire contents are incorporated herein by reference.

This disclosure relates to a grinder that performs processing such as grinding, polishing, and cutting on a workpiece.

The grinder has a spindle that is rotated by a motor. The spindle protrudes from the housing in which the motor is accommodated, and a disk-shaped tip tool is attached to the tip of the spindle when in use.

And when processing a workpiece with a tip tool, a user operates an operation switch provided on the outer wall of the housing. That is, in the grinder, when the user operates the operation switch, the motor is driven to rotate the spindle (and thus the tip tool).

JP 2013-78823 A JP 2013-226617 A

By the way, when processing the workpiece with the tip tool, the user grips the grinder housing and makes the tip tool contact with the workpiece while rotating the tip tool. Then, a reaction force is applied from the workpiece to the tip tool (and thus the grinder).

In addition, since the conventional grinder usually has only one operation unit to be operated for driving the motor, the user can easily drive the grinder even if the user does not hold the housing firmly. it can.

For this reason, in the conventional grinder, the user may start processing the workpiece without holding the housing firmly. In this case, the tip tool moves in a direction not intended by the user due to a reaction force applied from the workpiece, and the workpiece cannot be processed into a desired shape.

In one aspect of the present disclosure, it is desirable that the user can firmly hold the grinder with both hands when using the grinder.

A grinder according to one aspect of the present disclosure includes a housing in which a motor is housed and a spindle for attaching a tip tool that is rotationally driven by the motor is projected, and a handle portion that is fixed to the housing and is gripped by a user. Is provided.

The housing is provided with one or a plurality of first operation parts, and the handle part is provided with one or a plurality of second operation parts, and at least one of the first operation parts and the second operation part are provided. When at least one of them is operated simultaneously, the control unit starts driving the motor.

For this reason, the user cannot drive the motor without operating the operation parts provided on the housing and the handle part at the same time. When using the grinder, the user must hold the housing and the handle part with both hands. Become. Therefore, according to this grinder, the user can hold the grinder firmly with both hands.

Here, when the housing includes a first housing in which the motor is accommodated and a second housing in which the spindle is held and protruded, the handle portion is fixed to the second housing, and the first operation portion is It may be provided in the first housing.

Further, the number of first operation units may be larger than the number of second operation units. If it does in this way, by accommodating a motor, more operation parts can be provided now with respect to the 1st housing which becomes large compared with a handle part. And since a user should just operate at least 1 of the some 1st operation part, it can suppress that the operativity at the time of grinder use falls.

Further, when the first housing has a cylindrical outer wall around the central axis extending from one end side from which the spindle protrudes to the other end side, like a general grinder, the first operating portion is formed in the cylindrical shape. A plurality of the outer walls may be distributed in the circumferential direction.

In this way, the user can easily operate the first operation unit even if the first housing is rotated for processing the workpiece and the position where the first housing is gripped is changed. It becomes easy to ensure the operability of the first operation unit.

On the other hand, the grinder of another aspect drives the motor according to a motor, a spindle for attaching a tip tool rotated by the motor, an operation unit for inputting a motor drive command, and a drive command from the operation unit. And a housing.

The housing is for housing the motor, spindle, and control unit, and has a cylindrical outer wall around a central axis parallel to the rotation axis of the motor. A part of the spindle protrudes outward at one end side in the central axis direction of the outer wall. This is because the tip tool can be attached to the spindle protruding from the housing.

Further, the housing has two regions that divide the cylindrical outer wall into two along the central axis: a front housing region where the spindle projects and a rear housing region opposite to the front housing region.

The operation unit includes one or a plurality of front operation units provided in the front housing region and one or a plurality of rear operation units provided in the rear housing region.
The control unit starts driving the motor when at least one of the front operation unit and at least one of the rear operation units are operated simultaneously.

For this reason, the user cannot drive the motor without operating the operation portions provided in the front housing area and the rear housing area of the cylindrical outer wall constituting the housing at the same time. Therefore, when using the grinder, the user grips the front housing area and the rear housing area of the housing. Therefore, also in this grinder, the user can hold the grinder firmly with both hands.

Here, the number of front operation units may be larger than the number of rear operation units. In this way, the spindle on which the tip tool is mounted protrudes, and more front operation units can be provided in the front housing area that is more susceptible to reaction force from the workpiece than the rear housing area. It becomes like this.

For this reason, the user can easily operate the front operation unit with a hand holding the front housing region of the housing.
Further, a plurality of front operation portions may be provided in the front housing region in a distributed manner in the circumferential direction of the cylindrical outer wall constituting the housing.

In this way, the user can easily operate the front operation section even if the entire housing is rotated around the central axis for processing the workpiece and the position where the front housing area is gripped is changed. Thus, it becomes easy to ensure the operability of the front operation unit.

Next, the front housing area of the housing is provided with a handle portion for the user to hold, and the handle portion may be provided with one or a plurality of handle operation portions.

In this case, the control unit starts driving the motor when two or more of at least one of the front operation unit, at least one of the rear operation unit, and at least one of the handle operation unit are operated simultaneously. It may be configured as follows.

In this way, the user can drive the motor by operating the operation portions provided in any two of the front housing region, the rear housing region, and the handle portion of the housing. It becomes like this. Therefore, the user can select a part to be gripped with both hands when using the grinder, and can improve the usability of the grinder.

In this case, the number of rear operation units may be smaller than the number of front operation units and larger than the number of handle operation units. If it does in this way, it will become possible to provide more operation parts than a handle part with respect to the rear housing normally larger than a handle part, and it becomes easy for a user to operate a rear operation part. Moreover, since the number of front operation parts is larger than the number of rear operation parts, it can suppress that a front operation part becomes difficult to operate.

Next, the handle portion may be detachably fixed to the front housing region of the housing.
In this case, when the handle portion is mounted on the front housing region, the control portion operates at least two of at least one of the front operation portion, at least one of the rear operation portion, and at least one of the handle operation portions at the same time. When this is done, the motor may be configured to start driving.

The control unit is configured to start driving the motor when at least one of the front operation unit and at least one of the rear operation units are operated simultaneously when the handle unit is detached from the front housing region of the housing. May be.

If the control unit is configured in this way, the user must operate the operation units provided in two of the front housing region, the rear housing region, and the handle unit of the housing at the same time. Can not work. For this reason, the grinder can be firmly held with both hands for the user.

Next, in order to be able to detachably fix the handle portion to the front housing region of the housing, the handle portion is provided with a screw portion for fixing to a mounting hole provided in the front housing region of the housing. May be.

Further, in this case, when the handle operating unit and the control unit provided in the handle unit are connected by wire using a signal line, the handle unit is fixed to the housing by the mounting hole and the screw unit. A connection terminal to be connected may be provided.

And this connection terminal may be comprised by the coaxial terminal provided around the rotation center axis at the time of fixing a screw part to an attachment hole (in other words, screwing).
Further, the connection terminal is provided in the housing with an annular terminal provided on the outer peripheral portion of the protruding portion protruding in the direction of the rotation center axis when the screw portion is fixed to the mounting hole from the screw portion. A terminal abutting on the annular terminal.

In this way, when the connection terminal is constituted by a coaxial terminal or an annular terminal (so-called slip ring), in order to fix the handle portion to the housing, the screw portion is inserted into the mounting hole and rotated (in other words, The connection terminal does not get in the way when screwing.

Also, when the handle portion is fixed to the housing by the rotation, the handle portion side terminal and the housing side terminal can be connected so that the handle operation portion and the control portion can be connected by wire. Become.

On the other hand, the handle unit is provided with a transmission unit for wirelessly transmitting the operation state of the handle operation unit to the control unit, and the control unit receives a radio signal transmitted from the transmission unit and receives the received signal. A receiving unit for detecting that the handle operating unit is operated based on the above may be provided.

This makes it possible to wirelessly connect the handle operation unit and the control unit, and eliminates the need for a signal line for connecting them and the connection terminal described above. Further, since it is not necessary to wire the signal line in the housing, workability at the time of manufacturing the grinder can be improved.

Incidentally, since the handle portion is detachably fixed to the housing, it is conceivable that when the handle portion is not attached to the housing, the handle operation portion is erroneously operated and wirelessly transmitted from the transmission portion.

For this reason, when the handle portion is not fixed to the front housing region of the housing, the handle operating portion may not be operated.
The transmitting unit may be configured to wirelessly transmit the operation state of the handle operating unit when the handle unit is fixed to the front housing region of the housing.

If the transmission unit is configured in this way, it is not necessary to provide a mechanism for making it impossible to operate the handle operation unit, so that the configuration can be simplified.
In order to operate the transmission unit in this way, the user may manually stop the operation of the transmission unit or detect that the handle unit is fixed to the front housing area of the housing. A fixed state detection unit may be provided.

In the case where the handle portion is provided with the fixed state detection unit, the transmission unit detects the handle operation unit when the fixed state detection unit detects that the handle portion is fixed to the front housing region of the housing. The operation state may be configured to be transmitted wirelessly.

In this way, the operation / stop of the transmission unit is automatically switched according to the mounting state of the handle unit to the housing, and the usability can be improved.
On the other hand, since the handle portion is detachably fixed to the housing, the handle portion attached to the housing can be exchanged or shared by a plurality of grinders. For this reason, the reception unit can also receive a radio signal from a handle unit that is not attached to the housing or a transmission unit provided in the handle unit of another grinder.

Therefore, the receiving unit identifies the received signal from the handle unit fixed to the grinder provided with the receiving unit itself from the received signal, and the handle operating unit is operated based on the identified received signal. It is better to be able to detect this.

For this purpose, the receiving unit transmits the received signal from the transmitting unit of the handle unit attached to the housing of the grinder when the received signal includes identification information registered in advance. It may be configured to detect that the handle portion is operated based on the received signal.

The receiving unit enters the registration mode of the identification information under a predetermined condition, and is included in the received signal when a radio signal transmitted from the transmitting unit is received in a predetermined pattern by operating the handle operating unit. The identification information to be registered may be registered as the identification information of the transmission unit.

According to this configuration, the user can attach the handle portion to the grinder housing, shift the receiving portion to the registration mode under a predetermined condition, and operate the handle operation portion in a predetermined pattern, thereby providing the handle portion. The identification information of the transmitting unit can be registered in the receiving unit. Therefore, it is not necessary to provide a registration-dedicated device for registering identification information, and the device configuration can be simplified.

Next, the control unit may include a notification unit that notifies that when one of the operation units is operated when the driving of the motor is stopped. In this way, it is possible to notify the user that one of the operation units provided in the grinder has been operated, and the user can detect that the motor can be driven by operating another operation unit. Therefore, the operability of the grinder by the user can be improved.

Further, the control unit may be configured to continue driving the motor even after the operation unit being operated by the user becomes one after starting the driving of the motor. In other words, if the control unit starts driving the motor and the user starts processing the workpiece, the reaction force from the workpiece is reduced. Even if you remove your hand from one, the motor continues to drive. And if it does in this way, it can control that operation of a grinder stops in the middle of processing work, and it can control that workability falls.

In addition, when the operation unit being operated by the user becomes one and the motor is continuously driven, the elapsed time is measured, and when the elapsed time reaches the set time, the motor is driven. You may make it stop. In this way, wasteful power consumption can be reduced while ensuring workability as described above.

Next, at least one of the various operation units described above may be configured by a pressure sensor that generates an operation signal in response to pressure from the outside. If it does in this way, in order to apply a pressure to the pressure sensor which constitutes an operation part, a user will grasp the part (housing and handle part) in which the operation part was provided more firmly.

The pressure sensor may be composed of a pressure sensitive element whose resistance value changes according to the pressure received from the outside.
Further, the grinder may be provided with a main switch for turning on / off the power supply path to the motor in addition to the operation unit described above. In this way, when the control unit operates abnormally, the drive of the motor can be forcibly stopped using the main switch, so that the motor can be stopped more reliably when the motor should be stopped. be able to.

It is sectional drawing showing the internal structure of the grinder of embodiment. It is a top view showing the appearance of the grinder of an embodiment. It is the side view which looked at the grinder of FIG. 2 from the handle | steering-wheel part side. It is the bottom view which looked at the grinder of FIG. 2 from the bottom face side to which a front-end tool is attached. It is the side view which looked at the grinder of FIG. 2 from the rear end side by which a rear housing is arrange | positioned. It is the side view which looked at the grinder of FIG. 2 from the front end side to which a front-end tool is attached. It is a block diagram showing the structure of the whole drive circuit of a grinder. It is a circuit diagram showing the structure of the connection part of the gear housing of a grinder and a handle part. It is explanatory drawing showing the detection voltage output from the switch A detection circuit corresponding to a handle | steering-wheel part. It is a flowchart showing the control processing performed in a control circuit. It is a perspective view showing the external appearance of the grinder of a 1st modification. It is a perspective view showing the external appearance of the grinder of a 2nd modification. It is a circuit diagram showing the structure of the connection part of the gear housing and handle | steering-wheel part of a 4th modification. It is explanatory drawing showing the detection voltage output from the switch A detection circuit of a 4th modification. It is a flowchart showing the control processing performed with the control circuit of a 5th modification. It is a perspective view showing the internal structure of the handle | steering-wheel part of a 6th modification. It is sectional drawing showing the internal structure of the grinder of a 6th modification. FIG. 18A is a perspective view illustrating the internal configuration of the handle portion of the seventh modified example, and FIG. 18B is a cross-sectional view illustrating the internal configuration of the handle portion of the seventh modified example. It is a block diagram showing the structure of the whole drive circuit of a 7th modification. It is a flowchart showing the pairing process when there is no pairing switch. It is a flowchart showing a pairing process when there is a pairing switch. It is a perspective view showing the external appearance of the handle | steering-wheel part provided with LED and the terminal for electric power feeding. FIG. 23A is a perspective view illustrating the internal configuration of the handle portion according to the eighth modification, and FIG. 23B is a cross-sectional view illustrating the internal configuration of the handle portion according to the eighth modification.

2, 2A, 2B ... grinder, 4 ... motor housing, 4A ... main housing, 4B ... front housing area, 6 ... gear housing, 6A ... mounting hole, 8 ... rear housing, 8A ... sub housing, 8B ... rear housing area, DESCRIPTION OF SYMBOLS 9 ... Handle part, 9A ... Screw part, 12 ... Motor, 24 ... Spindle, 36 ... Tip tool, 40 ... Signal wire, 42, 46, 48, 82, 84, 92 ... Operation switch, 50 ... Circuit board, 52 ... Switch B detection circuit, 54 ... Switch C detection circuit, 56 ... Switch A detection circuit, 57 ... Wireless communication unit (reception unit), 58 ... LED, 60 ... Control circuit, 69 ... Pairing switch, 72 ... External power supply, 74 ... Main switch, 75 ... Trigger switch, 76 ... Bidirectional thyristor, 78 ... Drive circuit, 92A ... Pressure sensor, 95 ... Wireless communication Unit (transmission unit), 97 ... terminal (slip rings), 98 ... terminal portion 99 ... fixed state detection unit, 100 ... battery pack, T1, T2, T11, T12 ... terminal (coaxial terminal)

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.
As shown in FIG. 1, the grinder 2 of the present embodiment is mainly composed of a motor housing 4, a gear housing 6, a rear housing 8, and a wheel cover 10.

The motor housing 4 is a substantially cylindrical housing and houses the motor 12. The motor 12 is disposed in the motor housing 4 such that the rotation shaft 14 of the motor 12 is parallel to and substantially coincides with the central axis of the motor housing 4, and the rotation shaft 14 of the motor 12 faces the gear housing 6. It is protruding.

The rear housing 8 has a substantially cylindrical shape like the rear housing 8 and is provided on one end side of the central axis of the motor housing 4 (specifically, on the side opposite to the gear housing 6). A power supply wiring portion 16 is accommodated in the rear housing 8.

The power supply wiring portion 16 is provided with a power cord 18 that supplies current from an external power source and a circuit board 50, and the power cord 18 is electrically connected to the motor 12 via the circuit board 50. .

The circuit board 50 is connected to a handle portion 9 mounted on the gear housing 6 and various switches provided on the motor housing 4 and the rear housing 8 via signal lines 40 wired in the housings. ing.

The gear housing 6 is provided on the opposite side of the rear housing 8 of the motor housing 4 with the brake device 7 interposed therebetween, and accommodates the first bevel gear 20, the second bevel gear 22, the spindle 24, the bearings 26, 28, and the like. ing.

The brake device 7 is provided when a main switch 74 (in this embodiment, a slide switch: see FIGS. 2, 3, 4 and 7) provided on the outer wall of the gear housing 6 is switched off by an external operation. A braking force is applied to the rotating shaft 14 of the motor 12 by the movement of the brake member. The brake device 7 is described in detail in, for example, Japanese Patent Application Laid-Open No. 2013-022702, and detailed description thereof is omitted here.

The first bevel gear 20 is fixed to the rotating shaft 14 of the motor 12 in the gear housing 6. The second bevel gear 22, the spindle 24, and the bearings 26 and 28 are integrally provided in an internal housing 30 configured separately from the gear housing 6, and the internal housing 30 is fitted and fixed in the gear housing 6. As a result, the gear housing 6 is accommodated.

The inner housing 30 is provided with a spindle 24 through a bearing 26 so as to be rotatable. The inner housing 30 has a cylindrical shape coaxial with the central axis of the spindle 24, and is fixed in the gear housing 6 so that the spindle 24 is orthogonal to the rotating shaft 14 of the motor 12.

The second bevel gear 22 is fixed to the spindle 24, meshes with the first bevel gear 20 in the gear housing 6, and converts the rotational output of the motor 12 into a rotational force around the axis of the spindle 24.

One end of the spindle 24 is rotatably supported by the gear housing 6 via a bearing 28, and the other end of the spindle 24 protrudes to the outside from the internal housing 30 (in other words, the gear housing 6). .

An inner flange 32 for positioning and fixing the disc-shaped tip tool 36 is provided on the protruding portion of the spindle 24 from the gear housing 6. Further, a screw portion 25 for screwing the lock nut 34 is formed on the outer peripheral portion of the tip of the spindle 24 further than the inner flange 32. The lock nut 34 is for clamping the tip tool 36 with the inner flange 32.

In the grinder 2 configured as described above, when the main switch 74 is turned on, the motor 12 rotates, and the rotation output is transmitted to the gear mechanism (the first bevel gear 20 and the second bevel gear 22) in the gear housing 6. To the spindle 24.

For this reason, if the tip tool 36 is fixed to the spindle 24 via the lock nut 34, the tip tool 36 can be rotated to perform operations such as grinding, polishing, and cutting. As the tip tool 36 used in the grinder 2 as described above, a grinding wheel, a cutting wheel, a wire brush, and the like can be given.

The wheel cover 10 is intended to protect the user from scattering of work pieces and fragments of the tip tool 36 that occur during operations such as grinding, polishing, and cutting. For this reason, the wheel cover 10 is formed in a substantially semicircular shape so as to cover a part (approximately half in this embodiment) of the tip tool 36 fixed to the spindle 24 from the gear housing 6 side.

The wheel cover 10 is fixed to a portion of the inner housing 30 where the spindle 24 protrudes.
That is, in the inner housing 30, the attachment portion 31 for attaching the wheel cover 10 has a cylindrical shape that is coaxial with the central axis of the spindle 24 and surrounds the spindle 24.

Further, in the wheel cover 10, an outer periphery of the attachment portion 31 of the inner housing 30 is provided at a central portion of a semicircular plate surface disposed opposite to the plate surface of the tip tool 36 on the inner housing 30 side of the tip tool 36. A mounting portion 37 is provided for fixing to the head.

The attachment portion 37 has an annular shape that can be fitted onto the attachment portion 31 of the inner housing 30, and a part of the ring is opened so that it can be fastened and fixed around the attachment portion 31 by the fastener 38. It has become. In addition, since the structure of this attachment part 37 is also common in a grinder, description is abbreviate | omitted for the detail.

In the grinder 2 configured as described above, the wheel cover 10 can be detachably attached to the inner housing 30. Further, the wheel cover 10 can be rotated around the spindle 24 by loosening the tightening of the inner housing 30 by the mounting portion 37, and can be protected by the plate surface of the semicircular wheel cover 10. You can change the area.

The reason why the protection area can be changed in this way is that the area where the tip tool 36 should be exposed as viewed from the grinder 2 differs depending on the use of the tip tool 36 (grinding, polishing, cutting). The position of the wheel cover 10 can be changed according to the contents.

Next, as shown in FIGS. 2 to 6, the gear housing 6 is detachably provided with a handle portion 9.
Therefore, the gear housing 6 corresponds to an example of the second housing described above, and the motor housing 4 and the rear housing 8 correspond to an example of the first housing described above. Further, the outer wall of the motor housing 4, the gear housing 6, and the brake device 7 provided between them corresponds to an example of the above-described front housing region, and the rear housing 8 corresponds to an example of the above-described rear housing region. Is also equivalent.

The handle portion 9 is for the user to grip and position the grinder 2 by hand when the grinder 2 is used. As shown in FIG. 8, a screw portion 9 </ b> A for screwing into a mounting hole 6 </ b> A provided in the gear housing 6 and fixing to the gear housing 6 is provided at the base portion of the handle portion 9. .

Operation switches as operation units are provided on the outer walls of the motor housing 4, the rear housing 8, and the handle unit 9, respectively. This operation switch is a switch that is turned on when the user grips the motor housing 4, the rear housing 8, and the handle portion 9 and is pressed from the outside by the user's hand.

The motor housing 4 is provided with four operation switches 42, 44, 46, and 48. The operation switches 42 to 48 correspond to an example of the front operation unit or the first operation unit described above, and are arranged at intervals in the circumferential direction around the central axis of the motor housing 4. This is because the user can operate (press) at least one of the operation switches 42 to 48 regardless of the direction in which the motor housing 4 is gripped.

Further, the rear housing 8 is provided with operation switches 82 and 84 at two positions on the left and right sides of the central axis. The operation switches 82 and 84 correspond to an example of the rear operation unit or the first operation unit described above, and can be operated when the user holds the rear housing 8.

Further, since the user can hold the entire handle portion 9 with one hand, the handle portion 9 is provided with one operation switch 92. The operation switch 92 corresponds to an example of the second operation unit or the handle operation unit described above.

Next, the circuit board 50 provided in the rear housing 8 is connected to an external power source (in this embodiment, an AC power source such as a commercial power source) via a power cord 18 and a main switch 74 as shown in FIG. 72. Various circuit blocks for driving the motor 12 are mounted on the circuit board 50.

Here, the operation switch 92 provided in the handle portion 9 is connected to the switch A detection circuit 56 of the circuit board 50 as a handle area switch (hereinafter simply referred to as a switch A).

Since the handle portion 9 is provided detachably with respect to the gear housing 6, the coaxial connector shown in FIG. 8 is provided in the mounting hole 6 </ b> A of the gear housing 6 and the screw portion 9 </ b> A of the handle portion 9.

For this reason, when the handle portion 9 is attached to the gear housing 6, the terminals T11 and T12 on the operation switch 92 side are connected to the terminals T1 and T2 on the switch A detection circuit 56 side via a coaxial connector. The terminals T1 and T11 serve as the center conductor of the coaxial connector, and the terminals T2 and T12 serve as the outer conductor of the coaxial connector.

The operation switch 92 is provided with a resistor R2 connected in parallel to the pressure sensor constituting the switch, and both ends thereof are connected to terminals T11 and T12, respectively. In the switch A detection circuit 56, the terminal T1 is connected to the power supply line of the circuit board 50 via the resistor R1, and the terminal T2 is connected to the ground line of the circuit board 50.

As a result, as shown in FIG. 9, when the handle portion 9 is not attached to the gear housing 6, the voltage at the terminal T1 becomes the voltage value V1 corresponding to the power supply voltage.
When the handle portion 9 is attached to the gear housing 6 and the operation switch 92 is not operated, the voltage at the terminal T1 becomes a voltage value V2 obtained by dividing the power supply voltage by the resistors R1 and R2.

In addition, when the handle portion 9 is mounted on the gear housing 6 and the operation switch 92 is operated, the operation switch 92 is turned on, so that the voltage at the terminal T1 becomes substantially the ground potential (0 V).

From the switch A detection circuit 56, the voltage of the terminal T1, which changes as described above, is detected voltage V1, which indicates whether the handle portion 9 is attached and whether the operation switch 92 is operated. Output as V2,0.

The four operation switches 42 to 48 provided in the motor housing 4 are connected in parallel as motor housing area switches (hereinafter simply referred to as “switch B”), and the switch B detection circuit of the circuit board 50 is connected via a signal line. 52.

The two operation switches 82 and 84 provided on the rear housing 8 are connected in parallel as a rear housing area switch (hereinafter simply referred to as a switch C), and the switch C detection circuit of the circuit board 50 is connected via a signal line. 54.

Then, when at least one of the operation switches 42 to 48 constituting the switch B is operated and turned on from the switch B detection circuit 52, as with the output from the switch A detection circuit shown in FIG. A low level detection voltage lowered to (0V) is output.

Similarly, when at least one of the operation switches 82 and 84 constituting the switch C is operated to be turned on, the switch C detection circuit 54 outputs a low-level detection voltage that is substantially reduced to the ground potential (0 V). The

If the operation switches 42 to 48 or the operation switches 82 and 84 are not operated, a high level detection voltage corresponding to the power supply voltage is output from the switch B detection circuit 52 and the switch C detection circuit 54.

Next, the operation state of the switches A, B, C is monitored on the circuit board 50 based on the detection signals from the detection circuits 52, 54, 56, and when two of these switches are operated, A control circuit 60 for driving the motor 12 is provided.

In the control circuit 60, a bidirectional thyristor 76 is connected in series to a power supply path from the external power supply 72 to the motor 12 formed when the main switch 74 is in the ON state.

The circuit board 50 is also provided with a drive circuit 78 for driving the motor 12 via the bidirectional thyristor 76 and a zero cross detection circuit 62 for detecting the zero cross point of the AC voltage supplied from the external power source 72. ing.

The main switch 74 is configured by a slide switch, and is provided on the side surface of the motor housing 4 (the side on which the handle portion 9 is attached). For this reason, the user can permit the control circuit 60 to drive the motor 12 by sliding the main switch 74 to the on state.

The circuit board 50 includes a power supply circuit 66 that rectifies an AC voltage supplied from the external power supply 72 to generate a DC voltage for driving the internal circuit, and a switch detection circuit that detects an on / off state of the main switch 74. 64 is also provided.

The control circuit 60 is configured by an MCU (microcontroller unit), and drives the motor 12 when two of the switches A, B, and C are operated while the main switch 74 is on.

The driving process of the motor 12 is performed by turning on / off the bidirectional thyristor 76 via the driving circuit 78 and controlling the power supplied to the motor 12 based on the detection signal from the zero cross detection circuit 62. The

The control circuit 60 is connected to a speed change circuit 68 for the user to set the drive speed of the motor 12. The control circuit 60 supplies power to the motor 12 according to the set drive speed. Adjust.

Next, a control process executed in the control circuit 60 to drive the motor 12 based on the operation states of the switches A, B, and C will be described with reference to the flowchart shown in FIG.

As shown in FIG. 10, the control circuit 60 repeatedly executes the control process at a constant control cycle by waiting for a predetermined time to elapse in S110.
If it is determined in S110 that the predetermined time has elapsed, the process proceeds to S120, and it is determined whether or not the handle portion 9 is attached to the gear housing 6. This determination is made based on the detection signal (voltage) from the switch A detection circuit 56 shown in FIG. 9, and when the handle portion 9 is attached, the process proceeds to S130, and the handle portion 9 is attached. If not, the process proceeds to S210.

In S130, whether or not two or more of the switches A, B, and C are turned on is determined based on detection signals from the detection circuits 56, 52, and 54 corresponding to the switches A, B, and C. . If two or more of the switches A, B, and C are on, the process proceeds to S140, and if not, the process proceeds to S110.

In S140, the driving process of the motor 12 described above is started to start driving the motor 12, and the process proceeds to S150. In S150, it is determined whether or not the switch in the ON state is one of the switches A, B, and C after the start of driving of the motor 12.

If it is determined in S150 that there is only one switch in the on state, the process proceeds to S160 and starts counting by the time counter in order to measure the elapsed time thereafter. In S170, as in S130, it is determined whether two or more of the switches A, B, and C are turned on, and two or more of the switches A, B, and C are turned on. If so, the time counter is reset in S190. In S190, after resetting the time counter, the process proceeds to S150, and the same processing as described above is executed.

If it is determined in S170 that two or more of the switches A, B, and C are not in the ON state, the process proceeds to S180, and after the start of driving the motor 12, the set time is set based on the count value of the time counter. It is determined whether or not the above has elapsed. If the set time or more has elapsed, the process proceeds to S200 to stop driving the motor 12, and then the process proceeds to S110. If the set time or more has not elapsed, the process proceeds to S150.

On the other hand, in S210, since the handle portion 9 is not attached to the gear housing 6, it is determined whether or not both the switches B and C are turned on. If both the switches B and C are in the ON state, the process proceeds to S220, and the drive process of the motor 12 is started to start the drive of the motor 12. Otherwise, the process proceeds to S110. To do.

Next, in S230, after the drive of the motor 12 is started, it is determined whether or not the switch in the ON state is one of the switches B and C. If it is determined in S230 that there is only one switch in the on state, the process proceeds to S240, where the counting by the time counter is started in order to measure the elapsed time thereafter, and the process proceeds to S250.

In S250, similarly to S210, it is determined whether both the switches B and C are turned on. If both the switches B and C are turned on, the time counter is reset in S270. In S270, after resetting the time counter, the process proceeds to S230, and the same processing as described above is executed.

On the other hand, if it is determined in S250 that both switches B and C are not in the ON state, the process proceeds to S260, and from the count value of the time counter, has the set time elapsed since the start of driving of the motor 12? Judge whether or not. If the set time has elapsed, the process proceeds to S200 to stop the driving of the motor 12, and then the process proceeds to S110. If the set time has not elapsed, the process proceeds to S230.

In the control process shown in FIG. 10, the switches A, B, and C are all turned off after starting the driving of the motor 12 in S140 or S220 and before stopping the driving of the motor 12 in S200. When it becomes, it transfers to S200 and the drive of the motor 12 is stopped.

As described above, in the grinder 2 of the present embodiment, the handle portion 9, the motor housing 4 and the rear housing 8 are provided with the switches A, B and C, respectively, and when two of these are turned on, The drive of the motor 12 is started.

For this reason, when the user grips any two of the handle portion 9, the motor housing 4, and the rear housing 8 and turns on the corresponding switches, the user drives the motor 12 and grinder 2 Can be used.

Therefore, when using the grinder 2, the user can hold the grinder 2 firmly with both hands. Further, since the user can select the part to be gripped with both hands when using the grinder 2 from the three parts, the usability of the grinder 2 can be improved.

In addition, the number of operation switches constituting the switches A, B, and C is the largest in the switch B provided in the heaviest motor housing 4 in which the motor 12 is built, and the handle portion that allows the user to hold the whole with one hand. 9 has the least number of switches A.

Therefore, the user can easily turn on the switch B even if the gripping position of the motor housing 4 is changed, and the operability of the switch B can be improved. Further, since the number of operation switches provided in the rear housing 8 is also larger than that of the handle portion 9, it is possible to suppress the deterioration of the operability of the switch C.

When the handle portion 9 is removed from the gear housing 6, the switch A detection circuit 56 detects that fact, and the control circuit 60 determines that both the remaining switches B and C are turned on. Start driving the motor. For this reason, even when the handle part 9 is not attached to the grinder 2, the user can firmly hold the grinder 2 with both hands.

In addition, after starting the driving of the motor 12, the control circuit 60 continues to drive the motor 12 even if the number of switches operated by the user and turned on becomes one. Is continued for a set time or longer, the drive of the motor 12 is stopped.

Therefore, when the user releases his / her hand from one of the two switches, the processing operation of the workpiece by the grinder 2 is interrupted, and the workability is prevented from being deteriorated. It becomes easy to ensure the stability of work.

Also, the grinder 2 is provided with a main switch 74 for turning on / off the power supply path to the motor 12 with the switches A, B, C operated by the user when using the grinder.

For this reason, when the user does not use the grinder 2, the main switch 74 is turned off, so that when the grinder 2 is touched or placed, the two switches A, B, and C are turned on. The motor 12 can be prevented from being driven unintentionally.

Further, even when the motor 12 cannot be stopped due to an abnormality in the control circuit 60, the motor 12 can be forcibly stopped using the main switch 74. Therefore, according to the grinder 2 of this embodiment, when the motor 12 should be stopped by the main switch 74, the motor can be stopped more reliably.

As mentioned above, although one embodiment of this indication was explained, the grinder of this indication is not limited to the above-mentioned embodiment, and can take various modes.
For example, in the above embodiment, the housing of the grinder 2 is the gear housing 6 that holds the spindle 24 and projects a part thereof, the motor housing 4 that houses the motor 12, and the rear housing 8 that houses the circuit board 50. It was explained that it is constituted by.

However, the grinder of the present disclosure is the grinder 2A of the first modified example configured as shown in FIG. 11 or the grinder 2B of the second modified example configured as shown in FIG. The same effect can be obtained by applying the same as in the above embodiment.
[First Modification]
In the grinder 2 </ b> A shown in FIG. 11, a main housing 4 </ b> A in which the motor 12 and the circuit board 50 are accommodated is provided behind the gear housing 6. In addition, a sub-housing 8A formed in a cylindrical shape thinner than the main housing 4A is provided behind the main housing 4A so that the user can easily grip the main housing 4A.

In the grinder 2A, a main switch 74 is provided on the side wall of the main housing 4A, and a trigger switch 75 is provided on the main housing 4A side of the sub housing 8A.

Therefore, conventionally, in this type of grinder 2A, when the user operates the trigger switch 75 when the main switch 74 is on, the internal motor 12 can be driven. However, this makes it impossible for the user to firmly hold the grinder 2A with both hands.

Therefore, also in this type of grinder 2A, it is preferable to provide the operation switches 42 to 48, 82, and 84 in both the main housing 4A and the sub-housing 8A, respectively, as in the above embodiment.

The handle portion 9 that is detachably attached to the gear housing 6 is also provided with an operation switch 92 as in the above embodiment, and the control circuit 60 mounted on the circuit board 50 is the same as in the above embodiment. If the control process is executed, the same effect as in the above embodiment can be obtained.
[Second Modification]
In the grinder 2B shown in FIG. 12, the housing behind the gear housing 6 is configured as one housing, and a battery mounting portion for detachably mounting the battery pack 100 on the rear end side of the housing. 19 is formed. That is, the grinder 2B operates with direct current power supplied from the battery in the battery pack 100.

In this type of grinder 2B, the housing behind the gear housing 6 is divided into a front housing region 4B on the gear housing 6 side and a rear housing region 8B on the opposite side of the gear housing 6 along its central axis. 2 minutes.

Operation switches 42 to 48, 82, 84 are provided in the front housing area 4B and the rear housing area 8B, respectively, and the handle portion 9 that is detachably attached to the gear housing 6 is also provided. An operation switch 92 is provided.

In this way, the same effect as in the above embodiment can be obtained by executing the same control processing as in the above embodiment in the control circuit 60 mounted on the circuit board 50 in the main housing.

In the grinder 2B shown in FIG. 12, a trigger switch is provided as a main switch 74 in the rear housing region 8B.
[Third Modification]
On the other hand, in the above-described embodiment, the first modification, and the second modification, the switches A, B, and C that are turned on when the user grips these portions at the front and rear portions of the handle portion 9 and the housing. The drive of the motor 12 is started when two of them are turned on.

However, for example, a switch as an operation unit is provided at two different places constituting the grinder 2 such as the handle portion 9 and the motor housing 4, the handle portion 9 and the rear housing 8, and the motor housing 4 and the rear housing 8. May be.

In this case, in the above embodiment, when two switches are simultaneously turned on by performing the same control process (the process after S210 shown in FIG. 10) as when the handle portion 9 is removed. The driving of the motor 12 may be started.
[Fourth Modification]
Next, in the above embodiment, the operation switches provided in the handle portion 9, the motor housing 4, and the rear housing 8 are described as switches that are turned on when pressed from the outside.

However, the type of these operation switches may be appropriately selected depending on the site to be arranged. In this case, the operation switch may be a switch whose on / off state changes when the terminal portion is pressed, such as a micro switch, or a state where the user holds the corresponding part, such as a trigger switch. A switch that can be operated with a finger may be used.

Further, the operation switch is not a switch that switches between on and off states, and may be a pressure sensor such as a piezoelectric element or a strain gauge, for example.
As a pressure sensor, a film-like sensor called FSR (Force Sensing Register: registered trademark) is known. Since this pressure sensor is in the form of a film, it is easy to attach to the housing and handle part, and the resistance value changes (decreases) according to the pressure received from the outside. Similarly, it can be configured easily.

Therefore, as a fourth modified example, a case will be described in which a pressure sensor 92A configured with an FSR is used as an operation unit provided in the handle unit 9.
As shown in FIG. 13, the equivalent circuit of the pressure sensor 92A can be described as a series circuit of a switch that is turned on when pressed from the outside and a variable resistor whose resistance value changes according to the pressing force.

Therefore, if this pressure sensor 92A is used as a handle area switch and the circuit configuration up to the switch A detection circuit 56 (including the coaxial connector) is configured in the same manner as shown in FIG. The detected voltage is as shown in FIG.

That is, the detection voltage from the detection circuit 56 is such that when the handle portion 9 is not attached to the gear housing 6, the voltage at the terminal T1 becomes the voltage value V1 corresponding to the power supply voltage. When the handle portion 9 is attached to the gear housing 6 and the pressure sensor 92A is not operated, the voltage at the terminal T1 becomes a voltage value V21 obtained by dividing the power supply voltage by the resistors R1 and R2.

Further, when the handle portion 9 is attached to the gear housing 6 and the pressure sensor 92A is operated, the pressure sensor 92A is connected in parallel to the resistor R2, so that the voltage at the terminal T1 is the resistance value of the pressure sensor 92A. It changes according to.

The resistance value of the pressure sensor 92A changes according to the pressure received from the user's hand, and the lower the pressure, the lower the resistance value when the user grips the handle portion 9 firmly. As a result, the voltage at the terminal T1 also decreases.

Therefore, on the control circuit 60 side, when the detection voltage input from the detection circuit 56 is within the range from the voltage value V21 shown in FIG. 14 to the operation determination threshold voltage V31 shown in FIG. It may be determined that the gear housing 6 is attached.

On the control circuit 60 side, when the detection voltage input from the detection circuit 56 is lower than the threshold voltage V31 for operation determination, the user firmly holds the handle portion 9 and the pressure sensor 92A is operated. It may be determined that.

Therefore, even if a pressure sensor such as an FSR is used as the operation unit, it can be detected that the user has gripped the portion provided with the pressure sensor, and is used in the same manner as the operation switch of the above embodiment. be able to.

In the above embodiment, the motor housing 4 and the rear housing 8 have been described as being provided with operation switches at intervals in the outer circumferential direction. On the other hand, in the pressure sensor, the detectable region can be widened by lengthening the resistor pattern constituting the variable resistor.

For this reason, if the said pressure sensor is utilized as a detection part, it can wind in the outer peripheral direction of the handle | steering-wheel part 9, motor housing 4, rear housing 8, etc. which become attachment object by lengthening that length. In this case, since it is possible to detect that the user has gripped each of these parts with a single pressure sensor, the configuration can be simplified.
[Fifth Modification]
Next, in the above embodiment and the first to fourth modifications, there is no particular description about displaying an operation state when an operation switch or a pressure sensor as an operation unit is operated. When one of the buttons is operated, the user may be informed accordingly.

For this purpose, for example, as shown by a dotted line in FIG. 2, an LED 58 is provided on a portion of the outer wall of the housing of the grinder 2 that is easy for the user to see (the upper portion of the brake device 7 in FIG. 2). The control process may be executed according to the procedure shown in FIG.

Therefore, this control process will be described in the fifth modification. Note that the control process shown in FIG. 15 is basically executed in the same procedure as the control process shown in FIG. 10, and therefore, the difference from the control process shown in FIG. 10 will be described here.

Further, in the following control processing, the LED 58 is turned on, and therefore, as shown by a dotted line in FIG. 7, the circuit board 50 is provided with an LED drive circuit 59 for turning on the LED 58. It is assumed that the LED 58 is turned on via the LED drive circuit 59.

As shown in FIG. 15, in the control process of this modification, if it is determined in S120 that the handle 9 is attached to the gear housing 6, the process proceeds to S122, and the handle 9 is attached in S120. If it is determined that it is not, the process proceeds to S126.

In S122, since the handle portion 9 is attached to the gear housing 6, based on the detection signals from the detection circuits 56, 52, 54, it is determined whether one of the switches A, B, C has been turned on. to decide.

When it is determined in S122 that one of the switches A, B, and C is turned on, the process proceeds to S124, the LED 58 serving as the notification unit is turned on, and the process proceeds to S130.

In S122, when it is not determined that one of the switches A, B, and C is turned on (that is, when all of the switches A, B, and C are turned off), S122 is executed again. Thus, it waits for one of the switches A, B, and C to be turned on.

On the other hand, in S126, since the handle portion 9 is not attached to the gear housing 6, it is determined based on the detection signals from the detection circuits 52 and 54 whether one of the switches B and C is turned on. .

If it is determined in S126 that one of the switches B and C is turned on, the process proceeds to S128, the LED 58 serving as the notification unit is turned on, and the process proceeds to S210.
If it is not determined in S126 that one of the switches B and C has been turned on (that is, if all of the switches B and C are in the off state), S126 is executed again to switch Wait for one of B, C to turn on.

As described above, in this modification, when one of the switches A, B, C or the switches B, C (specifically, operation switches constituting these) provided in the grinder 2 is operated, the LED 58 is turned on, A message to that effect is displayed.

For this reason, the user can detect that the motor 12 can be driven by operating a switch different from the currently operated switch A, B, or C, and the usability of the grinder 2 can be improved.

After the LED 58 is turned on in S124 or S128, the LED 58 is continuously turned on until all the switches A, B, C or the switches B, C provided in the grinder 2 are turned off. May be. The LED 58 may be turned off when two of the switches A, B, and C are turned on to start driving the motor 12.

The LED 58 is an example of a notification unit for notifying that one of the switches A, B, and C or the switches B and C provided in the grinder 2 is operated. For this reason, as an alerting | reporting part, you may comprise the alerting sound generator for alerting | reporting with sound, such as a pilot lamp different from LED58, a display apparatus, or a buzzer, or these combination.
[Sixth Modification]
Next, in the above embodiment and the first to fifth modifications, the handle portion 9 is detachably attached to the gear housing 6 by screwing the screw portion 9A into the attachment hole 6A of the gear housing 6. The mounting holes 6A of the gear housing 6 and the screw portions 9A of the handle portion 9 are provided with terminals T1, T11, T2, and T12 that constitute the central conductor and the outer conductor of the coaxial connector, respectively, as connection terminals.

This is because when the handle portion 9 is fixed to the gear housing 6, the operation portion (the operation switch 92 or the pressure sensor 92A) on the handle portion 9 side is connected to the signal line 40 (and thus the switch). This is to automatically connect to the A detection circuit 56).

However, in order to connect the operation portion on the handle portion 9 side to the signal line 40 in this way, an annular terminal (so-called slip ring) arranged around the rotation center axis of the screw portion 9A as a connection terminal. ) Can also be used.

Therefore, in the sixth modified example, the handle unit 9 and the grinder configured to connect the operation switch 92 on the handle unit 9 side and the signal line 40 (and thus the switch A detection circuit 56) using a slip ring. The configuration of 2 will be described with reference to FIGS.

As shown in FIG. 16, the handle portion 9 of this modification is provided with a micro switch 94 and a movable portion 93 for the user to turn on the contact of the micro switch 94 by an external operation as the operation switch 92. ing.

Then, the lead wire drawn out from the micro switch 94 passes through the proximal end portion 9B of the handle portion 9 provided with the screw portion 9A at the tip end, and becomes a rod-like terminal member 96 protruding from the tip end of the screw portion 9A. It is connected.

The terminal member 96 is fixed in the screw portion 9A so that the center axis thereof coincides with the rotation center axis of the screw portion 9A, and a plurality of annular terminals (slip on the outer periphery of the protruding portion protruding from the screw portion 9A. Ring) 97 is provided. The plurality of annular terminals 97 are connected to lead wires drawn from the microswitch 94 inside the terminal member 96.

On the other hand, as shown in FIG. 17, when the handle portion 9 is fixed to the gear housing 6, the gear housing 6 is brought into contact with the plurality of annular terminals 97 so that each terminal 97 is placed in the gear housing. A terminal portion 98 for connecting to a signal line (not shown) is provided. The terminal portion 98 is provided with a plurality of terminals (so-called brushes) that are in contact with the plurality of annular terminals 97.

Therefore, even if the connection terminal is configured by a slip ring as in this modification, when the handle portion 9 is fixed to the gear housing 6, the operation switch 92 is connected to the signal line wired in each housing. 40 can be connected to the switch A detection circuit 56.
[Seventh Modification]
Next, in the embodiment and the first to sixth modifications described above, the operation unit (operation switch 92 or pressure sensor 92A) on the handle unit 9 side and the circuit board 50 are connected via the connection terminal and the signal line 40 described above. It was explained as being connected. However, for this connection, it is necessary to provide a connection terminal in the handle portion 9 and the gear housing 6 and to wire the signal line 40 in the gear housing 6, so that the connection work becomes troublesome.

For this reason, the handle unit 9 is provided with a transmission unit for transmitting the operation state of the handle operation unit (the operation switch 92 or the pressure sensor 92A) with a radio signal, and the control circuit 60 side receives the radio signal to operate the handle. It may be detected that the unit has been operated.

Hereinafter, the structure of the handle | steering-wheel part 6 and the circuit board 50 in the grinder 2 comprised in this way, and the operation | movement of the control circuit 60 are demonstrated as a 7th modification.
As shown in FIG. 18A and FIG. 18B, the handle portion 9 of this modified example has a micro switch 94 as an operation switch 92 and a micro switch by a user externally, as in the sixth modified example shown in FIG. A movable part 93 for turning on the switch 94 is provided. The microswitch 94 is provided with a wireless communication unit 95 as a transmission unit for transmitting the state of the microswitch 94 with a wireless signal.

Next, as shown in FIG. 19, the circuit board 50 provided in the rear housing 8 of the grinder 2 is provided with a wireless communication unit 57 instead of the switch A detection circuit 56. The wireless communication unit 57 is for receiving a wireless signal transmitted from the wireless communication unit 95 on the handle unit 9 side, and is a receiving unit of the present disclosure.

The wireless communication unit 95 on the handle unit 9 side transmits a wireless signal including its own identification information when the operation switch 92 (in other words, the handle area switch) is operated and the micro switch 94 is turned on. It is configured as follows.

Therefore, when the wireless communication unit 57 receives a wireless signal from the wireless communication unit 95, the wireless communication unit 57 extracts the identification information from the received signal, and when the extracted identification information is registered in advance, the operation switch 92 (in other words, The switch A) is turned on.

This is because a radio signal is received from a wireless communication unit 95 in the handle portion 9 that is not attached to its own grinder 2, such as the handle portion 9 attached to another grinder 2, and the operation switch 92 is turned on. This is to prevent erroneous detection of the failure.

The identification information is stored in the memory of the control circuit 60 by a pairing process to be described later. When the identification information is not stored in the memory, the grinder 2 is not attached with the handle 9. Judge that.

Therefore, the control circuit 60 can drive the motor 12 when two or more switches provided in the grinder 2 are operated by executing the control processing shown in FIG. 10 or FIG. .

Next, the pairing process executed to register the identification information of the wireless communication unit 95 on the handle unit 9 side in the control circuit 60 will be described with reference to FIGS.
20 illustrates a pairing process executed when the control circuit 60 is not connected to the pairing switch 69 indicated by the dotted line in FIG. 19. FIG. 21 illustrates the pairing switch 69 in the control circuit 60. Represents the pairing process executed when connected. The pairing switch 69 is a switch for the user to input a pairing process execution command, and is attached to the rear housing 8, for example.

When the pairing switch 69 is not provided, the grinder 2 is connected to the external power source 72 (or the battery pack 100) when the main switch 74 is in the on state as shown in FIG. The pairing process is executed on the condition that it has started.

That is, the control circuit 60 enters the identification information registration mode and executes the control process for driving the motor 12 on condition that the main switch 74 is in the on state when the power is turned on and started. Without starting, the pairing process of FIG. 20 is started.

In the pairing process of FIG. 20, first, in S310, the LED 58 is blinked in a predetermined blinking pattern to display the pairing standby state, and in S320, whether or not the wireless communication unit 57 has received a wireless signal. By waiting for the wireless signal to be received.

If it is determined in S320 that the wireless communication unit 57 has received a wireless signal, the LED 58 is blinked in a blinking pattern different from the blinking pattern in S310, and the wireless signal is currently being received during pairing. Is displayed, and the process proceeds to S340.

In S340, it is determined whether or not the wireless communication unit 57 has stopped receiving the wireless signal, so that the wireless signal cannot be received. If the wireless signal cannot be received, the process proceeds to S350.

In S350, the LED 58 is blinked with a blinking pattern different from the blinking patterns in S310 and S350, thereby displaying that the wireless signal is not being received during pairing.

In the subsequent S360, it can be confirmed that the handle area switch has been operated once by the determination processing in S320 and S340, so the number of operations is counted up. In the subsequent S370, the number of operations is a threshold value (for example, 3 times) It is determined whether or not the above has been reached.

In S360, when the same wireless signal as that received after the pairing process is started is received based on the identification information included in the received wireless signal, the number of operations is 1 to 2, 2 to 3 If not, the number of operations is set to 1.

If it is determined in S370 that the number of operations of the handle area switch (that is, switch A) is not equal to or greater than the threshold, the process proceeds to S320 again, and it is determined in S370 that the number of operations of switch A is equal to or greater than the threshold. Then, the process proceeds to S380.

In S380, the wireless communication unit 57 waits for a wireless signal determined that the number of operations has exceeded the threshold to be continuously received for a set time (for example, 10 seconds). When the wireless signal is continuously received for the set time or longer, the process proceeds to S390, and the pairing is completed by storing the identification information in the memory.

As a result, the control circuit 60 stores that the handle portion 9 is attached to the gear housing 6 and the identification information of the wireless communication unit 95 in the handle portion 9.
Finally, in S395, the process waits for the connection between the grinder 2 and the external power source 72 (or the battery pack 100) to be cut off. When the connection is cut off, the pairing process ends.

After the pairing process is completed, the power supply from the external power source 72 (or battery pack 100) is cut off, so the control circuit 60 stops operating, and then the grinder 2 and the external power source 72 (or battery pack 100). ) Is connected, the control circuit 60 is activated.

If the main switch 74 is in an off state at the time of activation, the control process described above is executed, and the grinder 2 operates normally.
Next, the pairing process of FIG. 21 is executed when the grinder 2 is connected to the external power source 72 (or the battery pack 100) and the control circuit 60 is operating. In this pairing process, first, in S300, it is determined whether or not the pairing switch 69 is turned on to wait for the user to operate the pairing switch 69.

When the user operates the pairing switch 69 and it is determined in S300 that the pairing switch 69 has been turned on, a series of processes from S310 to S370 are executed as in the pairing process of FIG.

That is, when there is the pairing switch 69, the control circuit 60 enters the identification information registration mode on the condition that the pairing switch 69 is operated and is turned on, and executes the processing from S310 onward.

In S370, if it is determined that the number of operations of the handle area switch (that is, switch A) is equal to or greater than the threshold, the process proceeds to S390, and the identification information of the radio signal that is determined that the number of operations is equal to or greater than the threshold By storing, pairing is completed, and the process proceeds to S395.

As described above, according to the pairing process shown in FIG. 20, after the power is turned on, the user turns on / off the operation switch 92 of the handle unit 9 a predetermined number of times (three times), and then the set time (10 seconds). The wireless communication unit 95 can be registered by operating the operation switch 92 as described above.

Further, according to the pairing process shown in FIG. 21, the user operates the pairing switch 69 after turning on the power, and then turns on / off the operation switch 92 of the handle portion 9 a predetermined number of times (three times). Thus, the wireless communication unit 95 can be registered.

Therefore, according to this modification, in order to register the identification information of the wireless communication unit 95 as a transmission unit in the control circuit 60, it is not necessary to provide a dedicated device for registration, and the device configuration can be simplified.

By the way, when the handle portion 9 is detached from the gear housing 6, it is necessary to delete the storage of the identification information of the wireless communication unit 95 and store that the handle portion 9 is not attached to the grinder 2.

For this purpose, for example, when the pairing standby state is displayed by blinking the LED 58 in S310, the identification information of the wireless communication unit 95 stored so far may be deleted. .

In this way, after the user starts the pairing process and restarts the control circuit 60 before the pairing is completed in S390, the handle unit 9 is attached to the grinder 2. You can remember that you are not.

In the seventh modification, the operation state of the handle operation unit (specifically, the operation switch 92) provided in the handle unit 9 is changed to a wireless communication unit 57 as a reception unit via a wireless communication unit 95 as a transmission unit. It was described as being wirelessly transmitted.

On the other hand, the motor housing switch (switch B) and the rear housing area switch (switch C) are also provided with a transmission unit, and the states of the switches B and C are wirelessly transmitted to the reception unit provided on the control circuit 60 side. May be.

In this case, since the motor housing switch (switch B) and the rear housing area switch (switch C) are not removed from the grinder 2, it is not necessary to perform the pairing process described above.

Further, when the wireless communication unit 95 as the transmission unit is provided in the handle unit 9, the wireless communication unit 95 may include a battery for supplying power, but when a dry battery or a button battery is used, FIG. 18A and FIG. As shown in 18B, it is necessary to disassemble the handle 9 and replace the battery.

Therefore, the wireless communication unit 95 is provided with a rechargeable secondary battery, and a charging terminal 86 is provided on the rear end side of the handle portion 9 as shown in FIG. The battery may be rechargeable.

Further, as shown in FIG. 22, the handle portion 9 may be provided with an LED 88 for displaying a communication state, and the LED 88 may be turned on when the wireless communication unit 95 is transmitting a wireless signal.

Note that the terminal 86 and the LED 88 can be easily realized because the terminal 86 and the LED 88 may be directly connected to the wireless communication unit 95 within the handle portion 9 as indicated by a dotted line in FIG.
[Eighth Modification]
By the way, in the seventh modified example, the control circuit 60 executes pairing processing so that the user can register / delete the identification information of the wireless communication unit 95.

However, when the user forgets to delete the identification information of the wireless communication unit 95 when the handle portion 9 is removed from the gear housing 6, the handle portion 9 removed from the gear housing 6 is operated to operate the motor 12. Can be driven.

Therefore, in the eighth modified example, when the handle portion 9 is not fixed to the gear housing 6, a wireless signal is prevented from being transmitted from the wireless communication unit 95 as a transmitting portion.
Specifically, as shown in FIGS. 23A and 23B, the handle portion 9 of the present modified example is further connected to the handle portion 9 of the seventh modified example shown in FIGS. 18A and 18B by a micro switch or the like. It is configured by providing a configured fixed state detection unit 99 and a rod-shaped link member 99A.

The link member 99A is provided so as to penetrate the base end portion 9B of the handle portion 9 in parallel with the screw portion 9A, and protrudes from the tip end of the screw portion 9A by a predetermined length ΔL.
The link member 99A is axially displaceable in the base end portion 9B. When the handle portion 9 is fixed to the gear housing 6, the link member 99A comes into contact with the outer wall of the gear housing 6 and moves toward the handle portion 9 side. Moving.

The link member 99A is in contact with the movable member of the fixed state detection unit 99 in the handle unit 9, and when the handle unit 9 is fixed to the gear housing 6 and moves to the handle unit 9 side, the fixed state detection is performed. The movable member of the unit 99 is displaced to switch the fixed state detection unit 99 from the off state to the on state.

The fixed state detection unit 99 is connected to the wireless communication unit 95, and the wireless communication unit 95 is configured to stop the transmission of wireless signals when the fixed state detection unit 99 is turned on.

Therefore, according to this modification, it is possible to prevent a wireless signal from being transmitted from the wireless communication unit 95 when the handle portion 9 is not fixed to the gear housing 6, and from the handle portion 9 removed from the gear housing 6. It is possible to prevent the motor 12 from being driven by the wireless signal.

On the other hand, in the above embodiment, the main switch 74 has been described as a slide switch, but any switch that can maintain an on / off state, such as a toggle switch, a paddle switch, or a trigger switch, may be used.

Further, a plurality of functions of one component in the above embodiment may be realized by a plurality of components, and one function of one component may be realized by a plurality of components. Further, a plurality of functions possessed by a plurality of constituent elements may be realized by one constituent element, or one function realized by a plurality of constituent elements may be realized by one constituent element. Moreover, you may abbreviate | omit a part of structure of the said embodiment. Further, at least a part of the configuration of the above embodiment may be added to or replaced with the configuration of the other embodiment. In addition, all the aspects included in the technical idea specified only by the wording described in the claims are embodiments of the present disclosure.

Claims (24)

1. A housing in which a motor is housed and a spindle for attaching a tip tool that is driven to rotate by the motor is projected;
   A handle portion fixed to the housing and gripped by a user;
   One or a plurality of first operating portions provided in the housing;
   One or a plurality of second operation parts provided in the handle part;
   A control unit that starts driving the motor when at least one of the first operation unit and at least one of the second operation unit are operated simultaneously;
   With a grinder.
2. The housing is
   A first housing in which the motor is accommodated;
   A second housing on which the spindle is held and protruded;
   The grinder according to claim 1, wherein the handle portion is fixed to the second housing, and the first operation portion is provided in the first housing.
3. The grinder according to claim 1 or 2, wherein the number of the first operation units is larger than the number of the second operation units.
4. The first housing has a cylindrical outer wall around a central axis extending from one end side to the other end side where the spindle protrudes, and a plurality of the first operating portions are dispersed in a circumferential direction of the cylindrical outer wall. The grinder according to claim 3 provided.
5. A motor,
   A spindle for attaching a tip tool that is rotationally driven by the motor;
   An operation unit for inputting a drive command of the motor;
   A control unit that drives the motor in accordance with a drive command from the operation unit;
   The motor, the spindle, and the control unit are accommodated, and a cylindrical outer wall is provided around a central axis parallel to the rotation axis of the motor, and a part of the spindle is externally disposed at one end side in the central axis direction of the outer wall. A protruding housing,
   With
   The housing bisects the cylindrical outer wall into a front housing region in which a part of the spindle projects along the central axis, and a rear housing region opposite to the front housing region. Has two areas,
   The operation unit includes one or more front operation units provided in the front housing region, and one or more rear operation units provided in the rear housing region,
   The grinder is configured to start driving the motor when at least one of the front operation unit and at least one of the rear operation units are operated simultaneously.
6. The grinder according to claim 5, wherein the number of the front operation units is larger than the number of the rear operation units.
7. The grinder according to claim 6, wherein a plurality of the front operation units are provided in the circumferential direction of the cylindrical outer wall.
8. A handle portion fixed to the front housing region of the housing for gripping by a user;
   One or a plurality of handle operating parts provided in the handle part;
   And the control unit drives the motor when two or more of at least one of the front operation unit, at least one of the rear operation unit, and at least one of the handle operation unit are operated simultaneously. The grinder according to any one of claims 5 to 7, wherein the grinder is configured to start.
9. The grinder according to claim 8, wherein the number of the rear operation units is smaller than the number of the front operation units and larger than the number of the handle operation units.
10. The handle portion is detachably fixed to the front housing region of the housing,
    The controller is
    When the handle portion is attached to the front housing region, two or more of at least one of the front operation portion, at least one of the rear operation portion, and at least one of the handle operation portions are operated simultaneously. When the motor starts to drive,
    When the handle portion is removed from the front housing region, the motor is started to be driven when at least one of the front operation portion and at least one of the rear operation portions are operated simultaneously. 10. A grinder according to claim 8 or claim 9.
11. The handle portion includes a screw portion for fixing to a mounting hole provided in the front housing region of the housing,
    The attachment hole and the threaded portion are provided with a connection terminal for connecting the handle operating portion and the control portion in a wired manner by connecting the handle portion to the housing by being fixed to the housing. The grinder according to claim 10.
12. The grinder according to claim 11, wherein the connection terminal is configured by a coaxial terminal arranged around a rotation center axis when the screw portion is fixed to the mounting hole.
13. The connection terminal is
    An annular terminal provided on the outer peripheral portion of the protruding portion protruding in the direction of the rotation center axis when the screw portion is fixed to the mounting hole from the screw portion;
    A terminal provided in the front housing region and abutted against the annular terminal;
    The grinder according to claim 11, comprising:
14. The handle unit is provided with a transmission unit for wirelessly transmitting the operation state of the handle operation unit to the control unit,
    The control unit is provided with a receiving unit that receives a radio signal transmitted from the transmitting unit and detects that the handle operating unit is operated based on the received signal. The grinder according to any one of 10.
15. 11. The transmitter according to claim 10, wherein the transmitter is configured to wirelessly transmit an operation state of the handle operation unit when the handle unit is fixed to the front housing region of the housing. Item 15. A grinder according to item 14.
16. The handle part is provided with a fixed state detection part for detecting that the handle part is fixed to the front housing region of the housing,
    The transmission unit wirelessly transmits an operation state of the handle operation unit when the fixed state detection unit detects that the handle unit is fixed to the front housing region of the housing. The grinder of claim 15, configured as follows.
17. The reception unit is one in which the reception signal is transmitted from the transmission unit of the handle unit attached to the housing of the grinder when the reception signal includes identification information registered in advance. The grinder according to any one of claims 14 to 16, wherein the grinder is configured to detect that the handle operating unit is operated based on the received signal.
18. The reception unit enters a registration mode of the identification information under a predetermined condition, and when the radio signal transmitted from the transmission unit is received in a predetermined pattern by operating the handle operation unit, the reception signal The grinder according to claim 17, configured to register identification information included in the identification information as the identification information.
19. The control unit according to any one of claims 1 to 18, wherein the control unit includes a notification unit that notifies that when one of the operation units is operated when driving of the motor is stopped. Grinder.
20. The controller according to any one of claims 1 to 19, wherein the controller is configured to continue driving of the motor after starting driving of the motor even if the number of operating units being operated by the user becomes one. The grinder of any one of Claims.
21. The control unit is configured to measure an elapsed time when the number of operation units being operated by the user becomes one, and to stop driving the motor when the elapsed time reaches a set time. The grinder described in 1.
22. The grinder according to any one of claims 1 to 21, wherein at least one of the operation units includes a pressure sensor that receives an external pressure to generate an operation signal.
23. The grinder according to claim 22, wherein the pressure sensor includes a pressure-sensitive element whose resistance value changes according to a pressure received from outside.
24. The grinder according to any one of claims 1 to 23, further comprising a main switch for turning on and off a power supply path to the motor.

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