Abstract: A method of switching between groups of battery packs for supplying power to a power tool includes connecting a first group of battery packs and a second group of battery packs to a battery pack interface, discharging the first group to supply power to the power tool, and determining, using an electronic controller, a first condition of the first group. The method also includes discharging the second group to supply power to the power tool based on the first condition, determining, via the electronic controller, a second condition of the second group, determining, via the electronic controller, whether the first group has reached end of discharge, and discharging, in response to determining that the first group has not reached end of discharge, the first group based on the second condition.

Abstract: An exemplary method generally relates to operating an access control device including a motor, a locking member, and a target component operably connected with the locking member. The motor may be operated to drive the locking member in a first direction from an initial position toward a desired position. When the locking member is blocked from moving beyond a blockage position, a target location of the target component is detected. The motor may then be operated to drive the locking member in a second direction opposite the first direction. The motor may then be operated to drive the locking member in the first direction toward the blockage position while monitoring the location of the target component. As the target component reaches the target location, the motor is supplied with a boost current to drive the locking member beyond the blockage position and toward the desired position.

Abstract: An access control device generally includes an electromechanical actuator operable to transition the access control device between a locked state and an unlocked state, an energy storage device operable to store electrical power from a power supply, and control circuitry. The control circuitry is configured to direct a first electrical power from the energy storage device to the electromechanical actuator in response to one or more first criteria. In a fail secure mode, the first electrical power is configured to cause the electromechanical actuator to transition the access control device to the locked state. In a fail safe mode, the first electrical power is configured to cause the electromechanical actuator to transition the access control device to the unlocked state. Certain embodiments further include a user-adjustable switch operable to transition the control circuitry between the fail secure mode and the fail safe mode.

Abstract: An access control system includes an electrically powered access control device for locking and unlocking a barrier, and an access controller coupled to the access control device. A Power over Ethernet (PoE) circuit receives power over an Ethernet cable and powers the access control device and the access controller. An active power supply buffer connects the access control device and the access controller with the PoE circuit.

Abstract: An exemplary method generally relates to operating an access control device including a motor, a locking member, and a target component operably connected with the locking member. The motor may be operated to drive the locking member in a first direction from an initial position toward a desired position. When the locking member is blocked from moving beyond a blockage position, a target location of the target component is detected. The motor may then be operated to drive the locking member in a second direction opposite the first direction. The motor may then be operated to drive the locking member in the first direction toward the blockage position while monitoring the location of the target component. As the target component reaches the target location, the motor is supplied with a boost current to drive the locking member beyond the blockage position and toward the desired position.

Abstract: An illustrative access control system includes a locking assembly operable in locked and unlocked states, and a drive assembly operable to actuate the locking assembly. The drive assembly includes an electromechanical actuator, and energy storage device, and a control system. The electromechanical actuator is operable, upon receiving power, to transition the locking assembly between the locked state and the unlocked state. The energy storage device is electrically coupled to the electromechanical actuator, and configured to store electrical power from the power supply when the drive assembly is coupled to the power supply. The control system is configured to couple the drive assembly to the power supply in response to a first condition, and to thereafter transmit energy only from the energy storage device to power the electromechanical actuator, based at least in part upon a level of energy stored in the energy storage device.

Abstract: An access control system includes an electrically powered access control device for locking and unlocking a barrier, and an access controller coupled to the access control device. A Power over Ethernet (PoE) circuit receives power over an Ethernet cable and powers the access control device and the access controller. An active power supply buffer connects the access control device and the access controller with the PoE circuit.

Abstract: An access control device generally includes an electromechanical actuator operable to transition the access control device between a locked state and an unlocked state, an energy storage device operable to store electrical power from a power supply, and control circuitry. The control circuitry is configured to direct a first electrical power from the energy storage device to the electromechanical actuator in response to one or more first criteria. In a fail secure mode, the first electrical power is configured to cause the electromechanical actuator to transition the access control device to the locked state. In a fail safe mode, the first electrical power is configured to cause the electromechanical actuator to transition the access control device to the unlocked state. Certain embodiments further include a user-adjustable switch operable to transition the control circuitry between the fail secure mode and the fail safe mode.

Abstract: An access control system includes an electrically powered access control device for locking and unlocking a barrier, and an access controller coupled to the access control device. A Power over Ethernet (PoE) circuit receives power over an Ethernet cable and powers the access control device and the access controller. An active power supply buffer connects the access control device and the access controller with the PoE circuit.

Abstract: An illustrative access control system includes a locking assembly operable in locked and unlocked states, and a drive assembly operable to actuate the locking assembly. The drive assembly includes an electromechanical actuator, and energy storage device, and a control system. The electromechanical actuator is operable, upon receiving power, to transition the locking assembly between the locked state and the unlocked state. The energy storage device is electrically coupled to the electromechanical actuator, and configured to store electrical power from the power supply when the drive assembly is coupled to the power supply. The control system is configured to couple the drive assembly to the power supply in response to a first condition, and to thereafter transmit energy only from the energy storage device to power the electromechanical actuator, based at least in part upon a level of energy stored in the energy storage device.

Abstract: An exemplary method generally relates to operating an access control device including a motor, a locking member, and a target component operably connected with the locking member. The motor may be operated to drive the locking member in a first direction from an initial position toward a desired position. When the locking member is blocked from moving beyond a blockage position, a target location of the target component is detected. The motor may then be operated to drive the locking member in a second direction opposite the first direction. The motor may then be operated to drive the locking member in the first direction toward the blockage position while monitoring the location of the target component. As the target component reaches the target location, the motor is supplied with a boost current to drive the locking member beyond the blockage position and toward the desired position.

Abstract: An access control system includes an electrically powered access control device for locking and unlocking a barrier, and an access controller coupled to the access control device. A Power over Ethernet (PoE) circuit receives power over an Ethernet cable and powers the access control device and the access controller. An active power supply buffer connects the access control device and the access controller with the PoE circuit.

Abstract: An access control system including a locking assembly and a drive assembly operable to actuate the locking assembly. The drive assembly includes an electromechanical actuator, an energy storage device, and a control system. The electromechanical actuator is operable, upon receiving power, to transition the locking assembly between a locked state and an unlocked state. The energy storage device is electrically coupled to the electromechanical actuator, and is configured to store electrical power from the power supply when the drive assembly is coupled to the power supply. The control system is configured to couple the drive assembly to the power supply in response to a first condition, and to thereafter transmit energy only from the energy storage device to power the electromechanical actuator, based at least in part upon a level of energy stored in the energy storage device.

Abstract: An access control system including a locking assembly and a drive assembly operable to actuate the locking assembly. The drive assembly includes an electromechanical actuator, an energy storage device, and a control system. The electromechanical actuator is operable, upon receiving power, to transition the locking assembly between a locked state and an unlocked state. The energy storage device is electrically coupled to the electromechanical actuator, and is configured to store electrical power from the power supply when the drive assembly is coupled to the power supply. The control system is configured to couple the drive assembly to the power supply in response to a first condition, and to thereafter transmit energy only from the energy storage device to power the electromechanical actuator, based at least in part upon a level of energy stored in the energy storage device.

Abstract: An illustrative access control system includes a locking assembly operable in locked and unlocked states, and a drive assembly operable to actuate the locking assembly. The drive assembly includes an electromechanical actuator, and energy storage device, and a control system. The electromechanical actuator is operable, upon receiving power, to transition the locking assembly between the locked state and the unlocked state. The energy storage device is electrically coupled to the electromechanical actuator, and configured to store electrical power from the power supply when the drive assembly is coupled to the power supply. The control system is configured to couple the drive assembly to the power supply in response to a first condition, and to thereafter transmit energy only from the energy storage device to power the electromechanical actuator, based at least in part upon a level of energy stored in the energy storage device.

Abstract: An illustrative access control system includes a locking assembly operable in locked and unlocked states, and a drive assembly operable to actuate the locking assembly. The drive assembly includes an electromechanical actuator, and energy storage device, and a control system. The electromechanical actuator is operable, upon receiving power, to transition the locking assembly between the locked state and the unlocked state. The energy storage device is electrically coupled to the electromechanical actuator, and configured to store electrical power from the power supply when the drive assembly is coupled to the power supply. The control system is configured to couple the drive assembly to the power supply in response to a first condition, and to thereafter transmit energy only from the energy storage device to power the electromechanical actuator, based at least in part upon a level of energy stored in the energy storage device.

Abstract: An illustrative access control system includes a locking assembly operable in locked and unlocked states, and a drive assembly operable to actuate the locking assembly. The drive assembly includes an electromechanical actuator, and energy storage device, and a control system. The electromechanical actuator is operable, upon receiving power, to transition the locking assembly between the locked state and the unlocked state. The energy storage device is electrically coupled to the electromechanical actuator, and configured to store electrical power from the power supply when the drive assembly is coupled to the power supply. The control system is configured to couple the drive assembly to the power supply in response to a first condition, and to thereafter transmit energy only from the energy storage device to power the electromechanical actuator, based at least in part upon a level of energy stored in the energy storage device.

Abstract: An illustrative access control system includes a locking assembly operable in locked and unlocked states, and a drive assembly operable to actuate the locking assembly. The drive assembly includes an electromechanical actuator, and energy storage device, and a control system. The electromechanical actuator is operable, upon receiving power, to transition the locking assembly between the locked state and the unlocked state. The energy storage device is electrically coupled to the electromechanical actuator, and configured to store electrical power from the power supply when the drive assembly is coupled to the power supply. The control system is configured to couple the drive assembly to the power supply in response to a first condition, and to thereafter transmit energy only from the energy storage device to power the electromechanical actuator, based at least in part upon a level of energy stored in the energy storage device.

Abstract: An integral, one-piece, metallic chord for use as the top and bottom chords of a roof truss. The chord comprises an elongated member of generally U-shaped, singly symmetric cross-section, having a base terminating at its longitudinal edges in mirror image legs. The base portion is planar with a central depressed rib formed therein and extending the length thereof. Each leg comprises a first planar portion perpendicular to and extending from its respective longitudinal edge of the base, followed by an inwardly sloped planar portion leading to a planar attachment portion which is perpendicular to the base portion and which terminates in a flange portion extending outwardly of the attachment portion and then upwardly and inwardly, ending in a longitudinal edge facing the attachment portion. The flange portions form semi-closed reinforcement members. The legs and their flange portions constitute the sides of the chord.

Abstract: A method for making silicone-poly(arylcarbonate) block copolymers is provided by intercondensing a hydroxyl-terminated polycarbonate oligomer with a halo-terminated polydiorganosiloxane in the presence of an acid acceptor.