Abstract: An electrodynamic braking device for a universal motor is proposed, wherein during a braking operation a field winding is supplied from a network, and an armature is directly short-circuited, and a braking operation is carried out using a program of a controller of a control electronics system, whereby good braking is achieved with relatively low brush wear. Such an electrodynamic braking device is advantageously applied in a power tool equipped with a dangerous tool.

Abstract: An image forming apparatus includes a plurality of motors, a controller which generates control signals to control the plurality of motors and output the control signals, and a plurality of motor drivers which control corresponding motors among the plurality of motors if the enable signal among the control signal is input, and does not control the motors although the common signal is input if the enable signal is not input. Accordingly, the image forming apparatus may control a plurality of motors which is not necessary to be driven at the same time using an enable signal and thus the motors may be effectively controlled with low expense.

Abstract: A vehicle drive device includes an engine (200), a motor generator (MG1) driven by the engine (200) and generating power, a motor generator (MG2) driving the vehicle and generating electric power at the time of regenerative braking, a battery (B) capable of exchanging power to/from the motor generators (MG1, MG2), a temperature sensor (10) detecting temperature of the battery (B), and a controller (30) controlling the motor generators (MG1, MG2). If reduction in a required driving torque value of the motor generator (MG2) is detected, the controller changes start timing of regenerative braking by the motor generator (MG2) dependent on an output of the temperature sensor (10).

Abstract: Real-time control of a dynamical system is provided by determining control variables that get as close as possible to producing a desired response. Additional consideration of physical limitations leads to a convex Quadratic Program with inequality constraints that needs to be solved in real-time. A new active set algorithm is described to solve the convex Quadratic Program efficiently that meets real-time requirements. Based on the key observation that the physical limitations of the system translate to optimal active sets that remain relatively unchanged over time (even though the actual optimal controls may be varying), starting guesses for the active set obtained from the final iterate in the previous time period greatly reduces the number of iterations and hence allows the Quadratic Programs to be solved to convergence in real-time.

Abstract: In response to detection of a skid of drive wheels based on an increase in angular acceleration ? of a rotating shaft of a motor, the control procedure of the invention refers to a map representing a variation in maximum torque Tmax against the angular acceleration ? and sets torque restriction of the motor to limit the torque level of the motor to the maximum torque Tmax corresponding to a peak value of the angular acceleration ?. When the torque restriction sufficiently lowers the angular acceleration ? to detect convergence of the skid, the control procedure cancels the torque restriction to a certain level of the maximum torque Tmax corresponding to a torque restoration limit ?1, which is set according to the degree of the skid. The torque restoration limit ?1 (that is, the maximum torque Tmax) is cancelled in a stepwise manner by a cancellation rate and a cancellation time corresponding to an additional accelerator depression relative to an accelerator opening at the time of detection of the skid.

Abstract: Rotation of a capstan motor is detected by a frequency detector, and supplied to a CPU as a rotation detection signal CFG. The CPU derives a period of the rotation detection signal CFG, calculates an average rotational speed of the capstan motor on the basis of the derived period, derives an attenuation value of the rotational speed on the basis of the calculated average speed, and thereby sets a braking time interval. As a result, calculation of the braking time using a highly accurate zero point detection with a frequency detector of one system becomes possible. The apparatus scale can be reduced.

Abstract: A serial fan set and rotation speed-matching curve generation method thereof are provided. The serial fan set comprises a rotation speed control module, a first fan and a second fan, in which the rotation speed control module is used to receive the power signal and produce the rotation speed driving signal corresponding to the power signal in accordance with the relations of the rotation speed-matching curve, so that the first fan and the second fan are operated at the matching rotation speed, thus producing the optimum operation efficiency and achieving the purpose of controlling the serial fan set.

Abstract: A driving control device for an actuator comprises a driving device to drive an actuator having an electric motor (30) and a driving control device (50) to control the rotation of the electric motor (30) by controlling the driving device. The driving control device includes an H bridge circuit constructed by four switching semiconductor elements (Tr1 to Tr4), and rotates the electric motor in normal and reverse directions by turning on and turning off the switching semiconductor elements (Tr1 to Tr4). The driving control device (50) conducts to activate and to stop the electric motor (30) by applying a PWM signal to the switching semiconductor elements (Tr3 and Tr4) constructing the lower arm of the H bridge circuit (51).

Abstract: A clutch includes a moving gear member 65 being rotated integrally with a wheel at all times and engaged with a fixed gear member 69 when it is moved in a first direction and disengaged from the fixed gear member when it is moved in a second direction, an armature 61 pushing out the moving gear member 65 in the first direction when it is rotated relatively to the moving gear member 65, and an electromagnetic coil portion 60 that applies brake resistance to the armature 61 by attracting the armature 61 by magnetic force to restrict a concurrently-rotating-state of the armature 61 and the moving gear member 65.

Abstract: A motor brake releasing device includes an electromagnetic brake for locking a motor shaft and a switch mounted between the electromagnetic brake and a releasing-power-supply for the brake. The switch can be operated by an AND signal produced by a motor driving signal and a motor-brake-release-permitting signal. This structure allows a motor brake to be released when a motor driving system encounters an obstacle, although the motor is left free. The structure also can prevent a final object of the motor shaft from dropping due to its own weight.

Abstract: Method and device for controlling a motor in a powered seat, wherein one of normal and reverse drive signals from manual or auto switch is detected by a central processing unit, which in turn provides a first period of time defined between one point when the motor starts to drive in normal direction and another point when the normal drive of the motor is stopped, and a second period of time defined between one point when the motor starts to drive in reverse direction and another point when the reverse drive of the motor is stopped, and then, a motor torque switch element brings resistor in electrical connection with the motor terminal, only druing one of those first and second periods of time.

Abstract: A conveyance (10) is provided with: automatic limiting (223) of the rate of change in power supplied to left (26a or 232a) and right propulsion motors, whether electrically or hydraulically propelled; dynamic braking of electric propulsion motors (26a and 26b) that is achieved by shorting a motor winding (150a) during a portion (233a) of an interval (217a) between power pulses (207a) of a pulse-width-modulated driving voltage (209a); power-off braking that is achieved by shorting a motor winding (150a) when no power pulses are being supplied; extended life of relays (144a & 148a) that is achieved by preventing current flow to the motors during opening and closing of the relay contacts (154a and 156a); and a solid-state switching device (168a and 170a) that is controlled by a signal in a single conductor (200a) and that provides an effective delay (219a and 221a) in switching between two circuits (152a and 160a).

Abstract: A dynamic braking system for a D.C. traction motor which is driven from an asymmetric bridge rectifier having freewheel diodes to permit circulation of motor generated current. The system employs field reversal to ensure a generated (braking) current direction the same as for motoring and this facility permits injection current braking by phasing up the supply bridges when the motor is braking with full excitation. The brake resistance is in two parts one of which forms an uncontrolled arm of the bridge, this part of the resistance being shunted by a thyristor. Part way through an injection braking process the supply bridge is phased down, the resistance bridge arm shorted out and the supply bridge phased up again. Lower losses and greater braking efficiency result.

Abstract: A solid-state motor control apparatus operative with a plurality of series motors to determine the selection of a power mode of operation and a brake mode of operation, and including a plurality of current sensors to establish the current flow in the motor armatures and in the motor fields.

Abstract: A motor control system for a pair of motors which drive respective wheels of a vehicle which is steered by controlling the relative speed of the motors includes switch means, and a pair of resistors which are connected in a series circuit including the motors, when no current is being supplied to the motors in order to provide electrical braking of the motors.

Abstract: Power control system comprising an intermittent device for applying intermittent voltage between intermittent voltage terminals; the intermittent device having a DC input terminal and at least one pair of intermittent terminals; a plurality of pairs of reverse series connected devices comprising control electrical valves and other electrical valves; said connected devices being connected in parallel between the intermittent voltage terminals; and a plurality of loads which are respectively connected to the series junctions of the plurality of pairs of reverse series connected devices.

Abstract: A microfilm reader has a film transport mechanism driven by separate forward and reverse motors. During operation, the driven one of the motors receives full AC power for driving it at high speed. During low speed operation, the driven motor receives partial power during half-cycles of one polarity, but only minimal power during half-cycles of opposite polarity. The undriven motor is pulled by its associated reel as the film is unwound therefrom. A large capacitor, which is part of a series circuit including both the forward and reverse motors, charges while either motor runs. When a driven motor is stopped, the capacitor is discharged into both of the motors to provide a unipolar field which produces a braking torque. Thus, the capacitor discharge not only stops the driven motor quickly and efficiently, but also stops the undriven motor to maintain film tension.