Patent classifications
B25D11/06
Impact tool
An impact tool includes a tool-accessory holding part, a body and a first hammering member. The tool-accessory holding part has a through hole extending in a hammering-axis direction and is configured to hold the tool accessory inserted into the through hole to be movable in the hammering-axis direction. The body is connected to the tool-accessory holding part in the hammering-axis direction and has an internal space communicating with the through hole. The first hammering member is linearly movable in the hammering-axis direction and configured to drive the tool accessory in the hammering-axis direction by colliding with the tool accessory. The tool-accessory holding part and the body are connected in the hammering-axis direction via a first elastic element to be movable relative to each other. A second elastic element is interposed between the first hammering member and the body in a radial direction with respect to the hammering axis.
Percussion tool
A method for reducing vibrations in a percussion tool includes activating, using an electronic controller of the percussion tool, the motor of the percussion tool, determining, using the electronic controller, that the percussion tool is in a loaded condition, and operating, using the electronic controller, the motor in accordance with a predetermined profile in response to determining that the percussion tool is in the loaded condition. The method also includes determining, using the electronic controller, that the percussion tool is in a no-load condition and operating, using the electronic controller, the motor with reduced speed in response to determining that the percussion tool is in the no-load condition.
LOW-SPEED SENSORLESS BRUSHLESS MOTOR CONTROL IN A POWER TOOL
A power tool is provided including a brushless motor having a stator defining a plurality of phases, a rotor rotatable relative to the stator, and power terminals electrically connected to the phases of the motor. A power unit is provided including power switches. A control unit is interfaced with the power unit to output a drive signal to one or more of the motor switches to drive the phases of the motor over a series of sectors of the rotor rotation. The control unit is configured detect incorrect rotation of the rotor by applying a first series of voltage pulses to a present sector and a second series of voltage pulses to a previous sector, measuring motor currents associated with the first and second series of voltage pulses, and comparing corresponding motor current measurements to detect a transition from the present sector to the previous sector.
Percussion tool
A percussion tool is used for performing a chiseling operation on a workpiece with a chisel. The percussion tool comprises a housing including a cylinder portion, a tool holder coupled to the cylinder portion for holding the chisel, and a percussion mechanism including a striker supported for reciprocation in the cylinder portion. The percussion mechanism is configured to impart repeated axial impacts to the chisel with the striker. The percussion tool further comprises a flange between the cylinder portion and the tool holder. Movement of the chisel within the tool holder toward the percussion mechanism is stopped by the flange.
STRIKING TOOL
A striking tool restricting movement of an intermediate member toward a striker reliably prevents no-load strokes. A hammer drill includes a cylindrical tool holder holding a tip tool, a motor, a piston that reciprocate with rotation from the motor, a striker that reciprocate in cooperation with the piston, an intermediate member reciprocably accommodated in the tool holder between the striker and the tip tool and in contact with a rear end of the tip tool at a normal strike to indirectly transmit a strike from the striker to the tip tool, and at least two ring members that move in a front-rear direction accommodated in the tool holder at a front of the intermediate member between the tool holder and the intermediate member. At least one ring member is made of metal.
Impact tool
An impact tool includes a tool body, a tool holder, a cylindrical member, a reciprocating member, a motor, a first rotary body, a second rotary body, a swinging member, and clutch mechanisms. The clutch mechanisms are disposed between the first rotary body and the second rotary body on a power transmission path from the motor to the swinging member. The tool holder and the cylindrical member move together as a movable unit with respect to the tool body between a front end position and a separate position, according to a pressing force applied to the tool holder. The clutch mechanisms are each configured to start transmission of the first rotary body to the second rotary body while the movable unit moves from the front end position to the separate position and to interrupt transmission while the movable unit moves from the separate position to the front end position.
Power tool with magneto-pneumatic striking mechanism
A power tool 1 including a bit socket 6 which is configured to hold a chiseling bit 7 so that the latter can move along an axis of movement 3. A magneto-pneumatic striking mechanism 2 includes a primary drive 22 that is arranged around the axis of movement 3 and that has a first magnet coil 46, a permanently and radially magnetizable ring magnet 42 and a second magnet coil 47 arranged consecutively in the striking direction 5. On the axis of movement 3, inside the magnet coils 46, 47, the striking mechanism 2 has a striker 4 and a striking block 13 arranged consecutively in the striking direction 5. An air cushion 23 acts upon the striker 4 in the striking direction 5.
POWER TOOL
A power tool, such as an impact driver, includes a motor having a rotor that rotates relative to a stator, and a centrifugal fan that rotates together with the rotor. A motor housing and a rear housing house the motor. Overlapping parts of the motor housing and the rear housing radially surround an outer circumference of the centrifugal fan. Air exhaust ports are defined in each of the overlapping parts and are offset in an axial direction of the rotor. Fluid communication paths are defined between the air exhaust ports in the overlapping parts. The fluid communication paths have an opening area or width in the axial direction that is smaller than an opening area or width in the axial direction of the air exhaust ports.
POWER TOOL
A power tool, such as an impact driver, includes a motor having a rotor that rotates relative to a stator, and a centrifugal fan that rotates together with the rotor. A motor housing and a rear housing house the motor. Overlapping parts of the motor housing and the rear housing radially surround an outer circumference of the centrifugal fan. Air exhaust ports are defined in each of the overlapping parts and are offset in an axial direction of the rotor. Fluid communication paths are defined between the air exhaust ports in the overlapping parts. The fluid communication paths have an opening area or width in the axial direction that is smaller than an opening area or width in the axial direction of the air exhaust ports.
POWER TOOL COMPONENT POSITION SENSING
Position sensing related to a component within a power tool. The component within the power tool is, for example, a hammer of an impact mechanism and can include one or more sensible features that allow a controller of the power tool to precisely determine the position, speed, and acceleration of the component. One or more sensors can be used to determine the rotational position of the hammer and the axial position of the hammer. The rotational position of the hammer can then be used to calculate, for example, rotational speed and acceleration of the hammer. With precise determinations of the rotational and axial position of the hammer, the controller of the power tool is able to precisely time the impact between the hammer and the anvil to optimize the impact between the hammer and the anvil (e.g., to maximize energy transfer between the hammer and the anvil).