Motor driven appliance

• US 9,853,586 B2
• Filed: 07/16/2015
• Issued: 12/26/2017
• Est. Priority Date: 07/23/2014
• Status: Active Grant

• Current Assignee: Makita Corporation
• Original Assignee: Makita Corporation
• Inventors: Kusakawa, Takuya, Ishikawa, Goshi, Omura, Motohiro
• Primary Examiner(s): Ismail, Shawki S
• Assistant Examiner(s): Islam, Muhammad S
• Application Number:
  US14/801,420
• Publication Number:
  US 20160028344A1
• Time in Patent Office: 894 Days
• Field of Search: 318139
• CPC Class Codes: H02J 7/0029 with safety or protection devices or circuits
• CPC Class Codes: H02J 7/00304 Overcurrent protection
• CPC Class Codes: H02J 7/00306 Overdischarge protection
• CPC Class Codes: H02J 7/00309 Overheat or overtemperature protection
• CPC Class Codes: H02J 7/0063 with circuits adapted for supplying loads from the battery
• CPC Class Codes: H02J 7/00714 in response to battery charging or discharging current
• CPC Class Codes: H02J 7/007182 in response to battery voltage
• CPC Class Codes: H02P 27/04 using variable-frequency supply voltage, e.g. inverter or converter supply voltage
• CPC Class Codes: H02P 27/06 using dc to ac converters or inverters H02P27/05 takes precedence
• CPC Class Codes: H02P 29/0241 the fault being an overvoltage
• CPC Class Codes: H02P 29/027 the fault being an over-current

Abstract

A motor driven appliance comprises a battery, a motor, at least one switch, a control unit, an abnormality detection unit, a determination unit, and a processing unit. The at least one switch comprises an operation switch. The control unit controls driving of the motor by controlling power supply from the battery to the motor when the operation switch is turned on. The abnormality detection unit detects abnormality of the appliance. The determination unit determines whether the detected abnormality is a first type abnormality that can be cleared when the operation switch is switched from on to off, or is a second type abnormality that cannot be cleared even if the operation switch is merely switched from on to off. The processing unit is configured to perform a specific process when it is determined that the detected abnormality is the second type abnormality.

Claims

1. A motor driven appliance comprising:

a battery;

a motor driven by electric power of the battery;

at least one switch comprising an trigger switch for driving the motor, the trigger switch operating a driving switch and a power switch to thereby control output of battery voltage from the battery;

a control unit configured to control driving of the motor by controlling power supply from the battery to the motor when the trigger switch is turned on;

an abnormality detection unit configured to detect an abnormality of the motor driven appliance;

a determination unit configured, when an abnormality is detected by the abnormality detection unit, to perform an abnormality type determination process of determining whether the abnormality is a first type abnormality or a second type abnormality, the first type abnormality being an abnormality, a state of which detected by the abnormality detection unit is cleared when the trigger switch is switched from on to off, and the second type abnormality being an abnormality, a state of which detected by the abnormality detection unit is not cleared just because the trigger switch is switched from on to off; and

a processing unit configured to perform a process when it is determined that the abnormality detected by the abnormality detection unit is the second type abnormality by the determination unit, and not to perform the process when it is determined that the detected abnormality is the first type abnormality.

2. The motor driven appliance according to claim 1,

wherein one or more switches of the at least one switch are set to be abnormality confirmation switches, and

wherein the abnormality type determination process comprising a step of, when the one or more of switches set to be the abnormality confirmation switches are turned on and when an abnormality is detected by the abnormality detection unit, determining whether the detected abnormality is the first type abnormality or the second type abnormality.

3. The motor driven appliance according to claim 1,

wherein the control unit is configured such that, if an abnormality is detected by the abnormality detection unit when the trigger switch is turned on, the control unit stops power supply from the battery to the motor even if the trigger switch remains turned on.

4. The motor driven appliance according to claim 1, comprising:

an appliance main body, the appliance main body including at least the motor, the control unit, the determination unit, and the processing unit; and

a battery pack configured to accommodate the battery and to be detachably attached to the appliance main body.

5. The motor driven appliance according to claim 2,

wherein at least the trigger switch is set to the abnormality confirmation switch, and

wherein the determination unit is configured such that, if an abnormality is detected by the abnormality detection unit when the trigger switch is turned on and the motor is being driven, the determination unit executes the abnormality type determination process while the trigger switch remains turned on.

6. The motor driven appliance according to claim 2,

wherein at least the trigger switch is set to be the abnormality confirmation switch, and

wherein the determination unit is configured such that, if an abnormality is detected by the abnormality detection unit while the trigger switch is turned on and the motor is driven, and when detection of the abnormality continues even after the trigger switch is once turned off and is then turned on again, the determination unit determines that the abnormality is the second type abnormality.

7. The motor driven appliance according to claim 2, further comprising

a display unit configured to display remaining energy of the battery,

wherein the process executed by the processing unit comprises a step of notifying occurrence of the second type abnormality by causing the display unit to display information indicating that the second type abnormality is occurring.

8. The motor driven appliance according to claim 2,

wherein the processing unit is configured such that, when the abnormality confirmation switch is turned on, and when an abnormality is detected by the abnormality detection unit and the determination unit determines that the abnormality is the second type abnormality, the processing unit continues the notification until at least the abnormality confirmation switch is turned off and a predetermined time elapses.

9. The motor driven appliance according to claim 4,

wherein the processing unit is configured to operate by electric power of the battery when the battery pack is attached to the appliance main body,

wherein the abnormality detection unit is at least included in the battery pack, and wherein the processing unit is configured, when started by the battery pack attached to the appliance main body, and when an abnormality is detected by the abnormality detection unit in the battery pack, to execute the process.

10. The motor driven appliance according to claim 5, further comprising

an operation signal output unit configured to output an operation signal indicating an operation state of the trigger switch to the abnormality detection unit,

wherein the abnormality detection unit is configured to output an abnormality detection signal indicating detection of an abnormality, when detecting the abnormality, and then stop the output of the abnormality detection signal, if the detected abnormality is the first type abnormality when the abnormality detection unit acknowledges that the trigger switch is switched from on to off based on the operation signal input from the operation signal output unit, and

wherein the determination unit is configured such that, if an abnormality is detected by the abnormality detection unit while the trigger switch is turned on and the motor is driven, the determination unit executes a pseudo-operation process to cause the operation signal output unit to output an operation signal indicating that the trigger switch is turned off, and then output an operation signal indicating that the trigger switch is turned on again, and, if the abnormality detection signal remains output from the abnormality detection unit even after execution of the pseudo-operation process, the determination unit determines that the abnormality detected by the abnormality detection unit is the second type abnormality.

11. The motor driven appliance according to claim 7,

wherein the at least one switch comprises a remaining energy display switch for causing the display unit to display the remaining energy of the battery,

wherein the remaining energy display switch is set as the abnormality confirmation switch,

wherein the processing unit is configured, if the determination unit determines that the second type abnormality is detected when the remaining energy display switch is turned on, to notify occurrence of the second type abnormality.

12. The motor driven appliance according to claim 10,

wherein the pseudo-operation process is a process to cause the operation signal output unit to output an operation signal indicating that the trigger switch is turned off and, after a predetermined time, to output an operation signal indicating that the trigger switch is turned on.