Abstract: A linear compressor includes a cylinder, a piston disposed in the cylinder and reciprocating along an axis of the cylinder, a stator core disposed outside the cylinder, a coil winding body that is disposed in the stator core and includes first to fourth coils that are spaced from each other in a circumferential direction, a mover connected to the piston and reciprocating along the axis by an electromagnetic interaction with the coil winding body, and a switch unit configured to connect the first and second coils and the third and fourth coils in series or in parallel depending on a magnitude of a load. The first and second coils are connected in series, and the third and fourth coils are connected in series. The first to fourth coils each have the same inductance.

Abstract: At least two asynchronous AC induction electrical machines in parallel connection with the power source respectively include a main winding and control winding for operating the electrical machines, wherein the individually load driving operations of the two electrical machines in cross-interlocked parallel connection with the power source respond to changes in individual electrical machine loading statuses to provide variable impedance operation so as to change the end voltage ratio between the individual electrical machines.

Abstract: For mutually cross-interlocked multiple asynchronous AC induction electrical machines of the present invention, wherein the applicable operating characteristic curves of the asynchronous AC induction electrical machines include the asynchronous AC induction electrical machine of various operating characteristics, wherein when they are provided for the individual operation in different loading conditions, it is characterized that the cross interlocked electrical machine can be used to increase or decrease the rotational speed of the individual operation.

Abstract: A power transmission device capable of adjusting a torque to be applied to an output shaft easily and removing a backlash between gears exactly, and a display device and a display panel pedestal that have the power transmission device. A power transmission device 101 includes a display panel 102, an output shaft 103 to which the display panel is connected, output gears 104 and 105 rotating integrally with the output shaft, transmission gears 106 and 107 engaged with the respective output gears, motors 108 and 109 providing driving forces to the respective transmission gears, and a control circuit 110 controlling the motors. The control circuit 110 causes the motors 108 and 109 to rotate the transmission gears 106 and 107 at different rotation numbers, and to transmit different driving forces to the respective output gears 104 and 105.

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: When an angular acceleration ? of a rotating shaft of a motor connected with a drive shaft exceeds a preset threshold value ?slip, which suggests the occurrence of a skid, the torque control procedure sets a maximum torque Tmax by referring to a map, which gives a smaller maximum torque Tmax with an increase in angular acceleration ?, and restricts the motor torque to the maximum torque Tmax. The maximum torque Tmax is fixed to a value corresponding to a peak value of the angular acceleration ? at the time of occurrence of a skid. The torque control procedure then integrates the angular acceleration ? to give a time integration thereof over an integration interval when the angular acceleration ? once exceeds the preset threshold value ?slip and decreases again below the preset threshold value ?slip by the motor torque restriction.

Abstract: A load in an electrical apparatus is driven by two motors M1, M2. Switching means (R1, R2) switches the motors M1, M2 between: a series configuration, in which the motors M1, M2 are connected in series across a power supply and driven with a dc supply; and a parallel configuration in which the motors M1, M2 are connected in parallel across the power supply and driven with an ac supply. In the series configuration, a bridge rectifier BR is switched across the ac supply to provide the dc supply for the motors M1, M2 and in the parallel configuration, the rectifier BR is removed from the circuit. The arrangement can be used to drive a drum of a washing machine or a load in some other kind of appliance.

Abstract: A power generator drives a rotating anode of an X-ray tube via a stator-rotor in which the stator receives the anode side high voltage potential. An isolating transformer is connected to an alternating current source which converts DC voltage to AC voltage via a rectifier bridge, a regulator and a switching inverter. The secondary winding of the isolating transformer is coupled to a second rectifier bridge for applying rectified voltage to a second switching inverter that generates the alternating currents for the stator windings. The second inverter receives the high voltage which is also applied to the tube to generate X-rays.