Abstract: An electrical switch includes an operating member carrying moving contacts which face, in opposite directions, two rows of fixed contacts. The operating member moves the moving contacts into and out of contact with the fixed contacts. Each moving contact may have opposite ends for contacting two adjacent fixed contacts on a corresponding side of the operating member. Springs provided between the moving contacts and corresponding side of the operating member bias the contact ends into contact with the corresponding rows of fixed contacts.

Abstract: A trigger assembly for an electric power tool, comprising a base and a trigger supported by the base. The base has a housing having first and second compartments separated by a partition with an aperture. A main switch is provided in the first compartment, having first and second contacts switching on and off the motor. A slider is provided in the first compartment and is movable by or with the trigger, and includes a sliding contact. The base includes an electronic control circuit mounted on a circuit board in the second.

Abstract: An electrical switch having a casing, at least two fixed contacts and a corresponding moving contact. The moving contact has two parts contactable with the fixed contacts respectively thereby closing the switch. An operating member is supported for movement for moving the moving contact to close the switch. A spring acts upon the moving contact such that its two parts are inclined at an acute angle relative to the fixed contacts, with at least one of the parts being spaced apart from the corresponding fixed contact while the switch is open. The moving contact is movable such that said at least one or both of its parts comes or come into contact with the corresponding fixed contact or contacts against the action of the spring. In particular, the moving contact is movable against the action of the spring to have its two parts turning through said acute angle until both parts are in contact with the corresponding fixed contacts.

Abstract: An electrical switch assembly for controlling an electrical appliance, wherein the assembly includes first and second electrical elements. The first element is an on/off switch for initially switching on the appliance. The second element is a pressure-sensitive variable resistor for adjusting the operating condition of the appliance. The variable resistor includes a first part having a resilient deformable and electrically conducting resistive surface and a second part. One of the parts is movable to press against the other part so that their surfaces bear against each other to make an electrical connection between the resistive surface and the element. The resistive surface and the element together provide a resultant resistance between the two contacts that declines as the area of contact increases corresponding to the pressure acting upon the two parts.

Abstract: A power supply module for use between an AC/DC power supply unit and an electrical power tool driven by an electric motor and powered by a rechargeable battery pack which has a normal operating voltage and a higher fully-charged terminal voltage. The module includes an input connectable to the supply unit and an output connectable in parallel to the battery pack, and an operating circuit for delivering DC power from the supply unit to the tool in parallel with the battery pack. The operating circuit provides a DC operating voltage at the output of a value between the normal operating voltage and the fully-charged terminal voltage of the battery pack, and provides an output current limited to a predetermined value. The circuit has a comparator for determining whether the output current is less than or is increasing toward exceeding the predetermined value provides a corresponding control signal.

Abstract: A trigger assembly for an electric power tool including an electric motor, comprising a base for fixing within the tool and a trigger supported by the base for inward and outward movement. The base has a housing having first and second compartments separated by a partition that includes an aperture. A main switch is provided in the first compartment, having first and second contacts co-operable to switch on and off the motor. A slider is provided in the first compartment and is movable by or with the trigger for moving the first and second contacts into contact with one another or apart, the slider including a sliding contact. The base includes an electronic control circuit mounted on a circuit board located in the second compartment for controlling the operation of the motor. The circuit board includes at least one conductive track for contact by the sliding contact through the aperture.

Abstract: A toroidal core for a toroid, including at least two toroidal rings that are stacked co-axially one upon another. At least one of the two toroidal rings has a body including a gap that forms a break in one side of the body. The gap avoids saturation of the core.

Abstract: An electrical switch comprising a casing, and at least one fixed contact and a elongate resiliently deformable movable contact member in the casing, said contact member having opposite first and second sides. The switch includes a switching member supported in sliding contact on the first side of and with intermediate parts of the contact member to cause the contact member to pivot against its resilience for making and breaking electrical connection with the fixed contacts. The contact member includes a fixed end at which it is cantilevered for pivotal movement and a trifurcated free end for contact with the fixed contacts. Resilient means is provided acting resiliently upon the second side of the contact member to maintain the sliding contact of the contact member with the switching member.

Abstract: An electrical switch comprising a casing, two rows of fixed contacts located within the casing and on opposite sides thereof, and a moving contact for making and breaking electrical connection between the fixed contacts of each row. An operating member is provided between the two rows of fixed contacts. The operating member is supported by the casing for relative movement along a path co-extensive with the two rows of fixed contacts to move the moving contacts into contact with and out of contact from the fixed contacts of the corresponding rows. The moving contacts are carried by the operating member on opposite sides thereof for movement thereby, facing the two rows of fixed contacts in opposite directions.

Abstract: A trigger controller for an electric power tool including a motor and a pull-trigger movable along a path having a foremost home position comprises a mechanical switch and a solid-state switch connected in series to the motor, wherein the mechanical switch includes a first moving contact, and the controller includes a second moving contact wherein the first and second moving contacts are movable to operate the mechanical and solid-state switches respectively at different predetermined travelling positions of the pull-trigger from the home position such that the two switches are caused to be initially closed at different times.

Abstract: An electrical switch comprising a casing, a fixed contact and a moving contact, and an actuator supported for movement to a first position thereby moving the moving contact into contact with the fixed contact. The actuator is movable to a second position for permitting the moving contact to move out of contact from the fixed contact. Resilient means biases the moving contact out of contact from the fixed contact. The switch includes a remover having a part provided adjacent the fixed contact and movable by the actuator moving to the second position for removing the moving contact from the fixed contact in case the moving contact stays in contact with the fixed contact.

Abstract: An electrical switch having a casing, at least two fixed contacts and a corresponding moving contact. The moving contact has two parts contactable with the fixed contacts respectively thereby closing the switch. An operating member is supported for movement for moving the moving contact to close the switch. A spring acts upon the moving contact such that its two parts are inclined at an acute angle relative to the fixed contacts, with at least one of the parts being spaced apart from the corresponding fixed contact while the switch is open. The moving contact is movable such that said at least one or both of its parts comes or come into contact with the corresponding fixed contact or contacts against the action of the spring. In particular, the moving contact is movable against the action of the spring to have its two parts turning through said acute angle until both parts are in contact with the corresponding fixed contacts.

Abstract: A trigger controller for an electric power tool including a motor and a pull-trigger movable along a path having a foremost home position. The controller comprises a mechanical switch and a solid-state switch connected in series to the motor. The mechanical switch includes a first moving contact movable by the pull-trigger. The controller includes a control unit including an IC chip connected to the solid-state switch for generating an adjustable control signal to turn on and off the solid-state switch for delivering an adjustable current via the mechanical switch to the motor. The controller includes an output selector including resistors interconnected in series and a second moving contact connectable selectively to junctions of the resistors and connected to the control unit for adjusting the control signal to operate, the solid-state switch. The second moving contact is movable by the pull-trigger.

Abstract: An electrical switch (100) comprising a casing (110), and three one fixed contacts (121-123) and a elongate resiliently deformable movable contact member (130) in the casing, said contact member (130) having opposite first and second sides. The switch (100) includes a switching member (140) supported in sliding contact on the first side of and with intermediate parts (131A-133A) of the contact member (130) to cause the contact member (130) to pivot against its resilience for making and breaking electrical connection with the fixed contacts (121-123). The contact member (130) includes a fixed end (134) at which it is cantilevered for pivotal movement and a trifurcated free end (131-133) for contact with the fixed contacts (121-123). Resilient means (150/150′) is provided acting resiliently upon the second side of the contact member (130) to maintain the sliding contact of the contact member (130) with the switching member (140).

Abstract: A toroidal core for a toroid, comprising at least two toroidal rings that are stacked co-axially one upon another. At least one of the two toroidal rings has a body including a gap that forms a break in one side of the body. The gap is present to avoid saturation of the core.

Abstract: A power supply module for use between an AC/DC power supply unit and an electrical power tool driven by an electric motor and powered by a rechargeable battery pack which has a normal operating voltage and a higher fully-charged terminal voltage. The module comprises an input connectable to the supply unit and an output connectable in parallel to the battery pack, and an operating circuitry for delivering DC power from the supply unit to the tool in parallel with the battery pack. The operating circuitry provides a DC operating voltage at the output of a value between the normal operating voltage and the fully-charged terminal voltage of the battery pack, and provides an output current limited to a predetermined value. The circuitry has a comparator for determining whether the output current is less than or has a tendency exceeding the predetermined value and then providing a corresponding control signal.

Abstract: A circuit breaker includes two movable contacts for electrical connection to a load and a power source, respectively, a movable contact holder holding the first contact, a first spring biassing the contact holder, and an actuator for moving the second contact into contact with the first contact. A locking frame locks the contact holder and, in turn, the first contact at a first position in the path of movement of the second contact, against the spring, for contact by the second contact. The locking frame pivots between a first locking position locking the contact holder in the first position and a second position releasing the contact holder from the first position. A second spring biasses the locking frame towards the second position. A solenoid holds the locking frame in the first position against the second spring. An electronic control circuit detects occurrence of a circuit fault and, in response to detecting a fault, disables the solenoid.

Abstract: An electrical switch comprising a casing and a rotor supported within the casing for rotation about an axis. The rotor has a first surface extending around the axis and a second surface extending transversely of the axis. A moving contact is mounted on the rotor for rotation therewith, which has first and second inter-connected parts adjacent the first and second rotor surfaces respectively. A plurality of fixed contacts is located laterally of the rotor for short-circuiting by the moving contact whereby the switch is closed. At least one of the fixed contacts has first and second inter-connected parts bearing resiliently against the first and second rotor surfaces respectively for contact with the corresponding fist and second moving contact parts according to the angular position of the rotor.

Abstract: An electrical switch assembly for controlling an electrical appliance, which assembly comprises first and second electrical elements. The first element is an on/off switch for initially switching on the appliance. The second element is a pressure-sensitive variable resistor for subsequently adjusting the operating condition of the appliance. The variable resistor comprises a first part having a resilient deformable and electrically conducting resistive surface, and a second part having a surface including two contacts and a resistive element connecting the two contacts. One of the parts is movable to press against the other part such that their surfaces bear against one another, thereby causing the resistive surface to deform against the surface of the second part over an area of contact and causing electrical connection between the resistive surface and element.

Abstract: According to the invention, a controller for a motor driven device is disclosed. The controller for the motor driven device having a motor that draws a current from a power supply to induce a forward motion in response to a load. The controller is conveniently coupled to the device for connection to the motor and for detecting a motor parameter indicative of the value of the load and for pulsing the current “on” and “off” at a predetermined cycle frequency when the value of the motor parameter exceeds a predetermined value for a predetermined period wherein each “on” cycle of the predetermined cycle frequency preferably is of sufficient duration to allow the motor to draw sufficient current in response to the load. Further, each “on” cycle of the predetermined cycle frequency is of sufficient duration to maintain sufficient current to the motor to normalize the forward motion.