Drilling machine
AssigneeHitachi Koki Co., Ltd.
InventorsShigeru Shinohara, Shun Suzuki, Masateru Niyada
Life of this patent
Estimating the term…
Abstract
A drive motor connected to a drill bit serves to actuate the drill bit. An electric current is allowed to flow through the drive motor to activate the drive motor. A mechanism serves to feed the drill bit with respect to a workpiece. The current flowing through the drive motor is sensed. A device stores a value of the current which is sensed when the drill bit is out of engagement with the workpiece. A determination is made as to whether or not a drilling process is completed in accordance with a value of the present sensed current and the stored value of the sensed current.
Claims13
A drilling machine comprising:
- (a) a drill bit;
- (b) a drive motor connected to the drill bit for actuating the drill bit;
- (c) means for supplying electric current to the drive motor to activate the drive motor;
- (d) means for feeding the drill bit with respect to a workpiece;
- (e) means for sensing the current supplied to the drive motor;
- (f) means for storing a value of the current which is sensed when the drill bit is out of engagement with the workpiece;
- and
- (g) means for detecting whether or not a drilling process is completed in accordance with a value of the present sensed current and with the stored value of the sensed current.
A drilling machine comprising:
- (a) a drill bit;
- (b) a drive motor connected to the drill bit for actuating the drill bit;
- (c) means for supplying electric current to the drive motor to activate the drive motor;
- (d) means for feeding the drill bit with respect to a workpiece;
- (e) means for sensing the current supplied to the drive motor;
- (f) means for detecting a completion of a drilling process in accordance with the sensed current;
- and
- (g) means for maintaining activation of the feeding means for a preset time from a moment at which the completion of the drilling process is detected.
A drilling machine comprising:
- (a) a drill bit;
- (b) a drive motor connected to the drill bit for actuating the drill bit;
- (c) means for feeding the drill bit with respect to a workpiece;
- (d) means for sensing an overload of the drive motor;
- (e) means for deactivating the feeding means when the overload of the drive motor is sensed;
- and
- (f) means for activating the feeding means a preset time after the feeding means is deactivated.
A drilling machine comprising:
- (a) a drill bit;
- (b) a drive motor connected to the drill bit for actuating the drill bit;
- (c) means for supplying electric current to the drive motor to activate the drive motor;
- (d) means for feeding the drill bit with respect to a workpiece;
- (e) means for sensing the current supplied to the drive motor;
- (f) means for determining whether or not the sensed current supplied to the drive motor becomes zero;
- and
- (g) means for deactivating the feeding means when the sensed current becomes zero.
Dependencies are inferred from the claim text.