Abstract: A power tool (1) is disclosed comprising a tool (3), a power source (5) arranged to power the tool (3), a throttle lever (7), a circuit board (9), and a human machine interface (10) comprising components (15, 17, 19) arranged on the circuit board (9). The power tool (1) further comprises a magnet (11) operably connected to the throttle lever (7), and a sensor arrangement (13) configured to sense the intensity of the magnetic field of the magnet (11). The sensor arrangement (13) is arranged on the circuit board (9).

Abstract: A handheld power tool includes an actuator arrangement, which includes a movable trigger member and a sensor arrangement. The trigger member includes at least one magnetic element, and the sensor arrangement is responsive to a displacement of the magnetic element along with the movable trigger member relative to the sensor arrangement. The sensor arrangement includes an analog magnetic field sensor configured to provide a signal proportional to the position of the magnet, a first digital magnetic field sensor configured to provide a first digital switching point in response to the position of the magnet, and a second digital magnetic field sensor configured to provide a second digital switching point in response to the position of the magnet.

Abstract: A power tool for orthopedic surgery is provided, which can be coupled with an attachment having one or more first magnets mounted thereon, and include a power tool body including a power tool case, an attachment fastening portion connected to one end of the power tool body, a motor power transmitting portion protruding toward the attachment fastening portion and transmitting power to the attachment, a motor that drives the motor power transmitting portion, a first magnetic sensor portion including a first magnetic sensor capable of sensing a magnetic field strength or number of the one or more first magnets, a control portion that controls the motor to operate below a preset maximum rotational speed and maximum torque value according to the magnetic field strength or the number sensed by the first magnetic sensor, and a power supply that supplies power to the motor and the control portion.

Abstract: In order to so improve a surgical machine comprising a housing and a surgical drive that maintenance of the machine is simplified, it is proposed that the drive and the housing be directly on indirectly connectable in a detachable manner. A method for controlling and/or regulating a surgical machine is also proposed.

Abstract: The present invention discloses a servo control circuit comprising: a first node for receiving a control voltage; a second node for receiving a feedback voltage; an operational amplifier controlling a current on a path according to the voltages at the first and second nodes, the path including an internal voltage node thereon; an analog to digital converter (ADC) for converting the voltage at the internal voltage node to a digital signal; and a control logic circuit for generating a servo control signal according to the digital signal.

Abstract: A method for reducing commutation-related acoustic noise in a fan system is provided. A constant frequency periodic signal is generated and a fan commutation event is synchronized with a zero level value of the constant frequency periodic signal. A system for controlling a direct current fan is provided. The system comprises a signal generator adapted to produce a periodic signal of a constant frequency and a phase-locked loop. A zero level value of the periodic signal is synchronized with a commutation event of the fan.

Abstract: A method of generating pulses includes setting a cycle based on a frequency of reference clock, determining a total number of the pulses to be generated during the cycle, calculating the number of one or more first reference clocks used to determine a width of one or more first pulses, the number of one or more second reference clocks used to determine a width of one or more second pulses, a first pulse number for the first pulses and a second pulse number for the second pulses on the basis of the cycle and the total number of the pulses, and generating the first pulse number of the first pulse and the second pulse number of the second pulses during the cycle. A motor control system employs the above pulse generating method and a pulse generator using the method to improve accuracy of controllability of a motor by generating the total number of the pulses during a cycle, and decrease a manufacturing cost.

Abstract: An electric motor controller controls the currents flowing through the phase windings of an electric motor. The electric motor controller includes driving stages for driving respective phase windings of the motor and a memory for storing samples of reference signals. The driving stages force currents corresponding to the reference signals through a respective phase winding of the motor. The electric motor controller includes circuitry to determine subdivision degree intervals of an electric rotation and circuitry for comparing one of the currents flowing through the respective phase windings of the motor with at least one of the samples of the respective reference signal in at least one portion of each one of the degree intervals.

Abstract: A direct current motor drive circuit comprises: a hall element; an H-bridge drive circuit which receives an input of a sinusoidal signal outputted from the hall element and outputs rectangular wave signals corresponding to the sinusoidal signal; a dead time circuit which carries out rectangular wave signal processing for the rectangular signals; and an H-bridge circuit which receives the output signals of the dead time circuit, in that the H-bridge circuit includes a first series circuit in which a second switching element connected to a positive power supply voltage and a first FET connected to the ground are connected in series via a first node, a second series circuit in which a first switching element connected to the positive power supply voltage and a second FET connected to the ground are connected in series via a second node, and a coil of the direct current motor connected to the first node and the second node.

Abstract: A system for controlling a brushless direct current (BLDC) motor includes a power supply having a controllably alterable voltage output, and a controller in electrical communication with the power supply and the motor. The controller receives the voltage output of the power supply and can provide a pulse-width-modulated input voltage to the motor. Additionally, the controller can measure an average input current to the motor and a speed of the motor and thereafter alter the voltage output of the power supply based upon the average input current to the motor and the speed of the motor. In a further embodiment, the system can include an acoustic coating disposed about an outer surface of the motor and the controller.

Abstract: An H-bridge motor driving circuit has, between a PWM comparator and a control circuit, first and second frequency dividers for frequency-dividing, by 2, an AND gate, OR gate, and first and second and second inverters. During a first period, the first and second MOS transistors are turned on, and the second and third MOS transistors are turned off, caused a current to flow through a motor. During a next second period, the third and fourth MOS transistors are turned on, and the first and second MOS transistors are turned off, causing a regenerative current to flow through the motor. During a next third period, the MOS transistors are turned on and off in the same manner as during the first period, causing a current to flow through the motor. During a final fourth period, the first and second MOS transistors are turned on, and the third and fourth MOS transistors are turned off, caused a regenerative current to flow through the motor.

Abstract: A method and apparatus to automatically reverse the motor of a dispensing gun or similar tool. The invention includes a controller that automatically reverses the direction of plunger movement and removes the plunger from contact with the back wall of a cartridge. The controller has a trigger switch that is coupled to a power source, such as a battery, and includes a main power on/off switch and a potentiometer. A protection or secondary switch is coupled in parallel to the main power on/off switch. A power supply circuit and a commutator are each coupled to the main and secondary switches. An overload sensor is coupled to the commutator. The controller includes a programmable device that is coupled to the power supply circuit, the potentiometer, the commutator, and the overload sensor.

Abstract: A motor controller for regulating the application of current to the windings of a motor in order to both control the actuation of the motor rotor and the braking of the rotor. The motor controller includes a speed control circuit regenerating a signal representative of the user-selected speed, a direction controller to signal if the motor is to be driven in the forward, reverse or oscillatory motion and a speed override circuit. There is also a current sensor for monitoring the current drawn by the motor, a brake controller and an energization circuit. The energization circuit regulates the application of a current to the motor to cause the rotation or braking of the rotor. When the motor is to be oscillated, each time the direction controller circuit transitions a FORWARD/REVERSE signal, the speed override circuit causes the energization circuit to momentarily apply energization signals to the motor based on the application of a zero-speed, user-speed signal.

Abstract: A process controller controls an integrating-type process based on a measured process variable and a set point. The process controller includes an error generating circuit, a non-integrating control circuit and an adaptive bias circuit. The error generating circuit generates an error signal based on a difference between the set point and the measured process variable. The control circuit generates a control signal as a function of the error signal. The adaptive bias circuit adds a bias value to the control signal, the measured process variable or the set point. The bias value is selectively updated as a function of the error signal to force the error signal toward zero.

Abstract: A powered surgical tool includes a motor, a motor control module for controlling the actuation of the motor, and a trigger assembly for allowing the user to enter user-selected commands indicative of desired motor rotation. The trigger assembly includes a number of moving magnets located adjacent the sealed housing that contains the circuitry forming the motor control module. There are a set of magnetic field sensors in the motor control module housing. As the magnets are displaced in response to the user's actuation of the switches, the sensors generate signals representative of the user-selected motor commands. The motor control module further includes a motor control circuit and a direction controller circuit that allow the motor to be driven in either forward, reverse or oscillatory rotation.

Abstract: An electric control for gas furnaces which controls a two speed main blower fan and an induction draft fan based on inputs from a room thermostat, a high limit and an ignition control including a gas valve. The control has a circuit board having a power supply for providing 24 volts DC current source to drive DC relays and a 5 volt DC power source to power a microprocessor. 24 volt AC input signals are coupled to the input ports of the microprocessor through current limiting resistors and to AC ground through pull down resistors. AC ground is also connected to the IRQ port of the microprocessor. The output ports of the microprocessor are connected to a relay driver which in turn is connected to the relays. Several breakaway tabs in the board provide optional features such as eliminating a normally provided draft delay timing function. Test pads are provided on the board so that the board can be tested during manufacture.

Abstract: In a motor control device, an electric circuit responsive to a mode selection signal for determining whether or not an electric motor is driven is constructed with two field-effect transistors. A source terminal of the first field-effect transistor is connected to one of terminals of the motor, and a source terminal of the second field-effect transistor is connected to the other terminal of the motor. The mode selection signal is applied to the gate terminal of each of the two field-effect transistors. The drain terminal of the first field-effect transistor is connected to the output of a circuit for generating a drive signal for driving the motor, and the drain terminal of the second field-effect transistor is grounded. The accuracy of control is not lowered as the number of cycles of changing operation over between the manual and motor-driven modes increases, and the electric power is less consumed in each cycle over.

Abstract: AC power supply is converted to DC by a rectifier circuit. The DC is stepped up by a step-up chopper circuit. The output of the step-up chopper circuit is smoothed by a smoothing circuit. The output of the smoothing circuit is input to an inverter via a current detecting circuit and a voltage detecting circuit. A synchronous motor is connected to the inverter. When the speed of the synchronous motor is judged to be in a high speed region based on the output signal of the voltage detecting circuit, the first speed control apparatus operates the interrupting control of the switching element of the step-up chopper circuit in such a manner that a deviation speed between an instruction speed signal to the motor and the detected speed of the motor reaches to zero.

Abstract: A circuit for controlling the speed of a DC motor provides delay and sampling means in the feedback loop to delay the triggering of the SCRs driving the DC motor and measured the motor armature voltage during the period of the delay, thereby eliminating errors in the armature motor voltage caused by the SCR motor excitation.Alternatively, the current to the motor is measured to generate a pulse output for initiating an interval during which the measured armature voltage is sampled and transmitted to a summator for generating an error signal controlling application of power to the DC motor whereupon the aforesaid interval is terminated upon receiving a pulse indicative of power application to the DC motor.

Abstract: There is provided a continuous flow type homogenizer. The homogenizer comprises, a tubular container having at upper end thereof an inlet for introducing tissue to be homogenized and at lower end thereof an outlet for discharging the homogenized tissue, a pestle disposed freely rotatable in the tubular container with a clearance defined between the inner surface of the tubular container and the peripheral surface of the pestle, a rotation shaft driving means connected to a rotation shaft of the pestle, a speed setting means for setting the rotation speed of the pestle, and a speed controlling means for controlling the speed of the rotation shaft with a predetermined speed gradient with respect to a speed value set by the speed setting means.