Abstract: A motor current calculation device includes a first wire, a current detecting unit, a decision unit, and a calculation unit. The first wire is configured and arranged to carry flow of a motor current that has been passed through a motor and a drive current that has been passed through a motor drive unit to drive the motor. The current detecting unit is configured and arranged to detect a sum of the motor current and the drive current flowing through the first wire. The decision unit is configured and arranged to determine a first detection result of the current detecting unit when the motor is not rotating as the drive current. The calculation unit is configured to calculate the motor current by subtracting the drive current determined by the decision unit from a second detection result of the current detecting unit when the motor is rotating.

Abstract: A motor current detecting device includes a first wire, an instantaneous current detecting unit, an average electric current detecting unit, and a calculation unit. The first wire is configured and arranged to carry flow of a motor current that has been passed through a motor and a drive current that has been passed through a motor drive unit to drive the motor. The instantaneous current detecting unit is configured and arranged to detect an instantaneous value for a sum of the motor current and the drive current flowing on the first wire. The average electric current detecting unit is configured and arranged to detect an average value of the sum of the motor current and the drive current flowing on the first wire. The calculation unit is configured to calculate the motor current on the basis of the instantaneous value and the average value.

Abstract: A boot capacitor that functions as an operating power supply for a high-arm-side transistor provided in an inverter has to be charged prior to normal operation of a motor. This operation of charging the boot capacitor is performed at a carrier frequency that is lower than a carrier frequency for the normal operation.

Abstract: A current detecting device includes a current leveling unit, a first wire and a current detecting unit. The current leveling unit is configured to level a drive current that is passed through a motor drive unit to drive a motor. The first wire is configured and arranged to carry flow of a motor current that has been passed through the motor and the drive current that has been leveled by the current leveling unit. The current detecting unit is configured to detect a sum of the motor current flowing on the first wire and the drive current that has been leveled flowing on the first wire.

Abstract: Disclosed is a process for production of a liquid developer for use in electrophotograph or electrostatic recording by coacervation method. The process can produce a liquid developer in which a coloring agent (e.g., a pigment) is included completely within a resin particle by distillation of a solvent while retaining the state where the coloring agent are finely dispersed and the resulting colored resin particle is small in particle size and has an excellent dispersion stability, and which has excellent optical properties.

Abstract: Disclosed is a process for production of a liquid developer for use in electrophotograph or electrostatic recording by coacervation method. The process can produce a liquid developer in which a coloring agent (e.g., a pigment) is included completely within a resin particle by distillation of a solvent while retaining the state where the coloring agent are finely dispersed and the resulting colored resin particle is small in particle size and has an excellent dispersion stability, and which has excellent optical properties.

Abstract: Two current threshold values are adopted, which are larger than the upper limit of current of an operating region. When a rotating speed is smaller than a speed threshold value, the current threshold value is adopted as a criterion to judge whether an input current to an inverter is abnormal, and when the rotating speed Rot is larger than that, the other current threshold value is adopted as the criterion.

Abstract: An object of the present invention is to provide a carbodiimide type compound having high dispersibility and dispersion stability of pigments, fine resin particles, and pigment-resin composite fine particles particularly in a silicone dispersion medium; a pigment dispersion composition and a pigment-resin composite fine particles-containing dispersion composition preferably usable in a wide range of fields such as inks for solvent ink jet, liquid developers, and the like by using the compound; and a liquid developer using such a pigment dispersion composition and/or pigment-resin composite fine particles-containing dispersion composition. The present invention provides a carbodiimide type compound obtained by introducing a polysiloxane chain by reaction of a functional group of a polysiloxane chain-containing compound having the functional group reactive with a carbodiimide group with a carbodiimide group of a carbodiimide compound having a carbodiimide equivalent weight of 100 to 50000.

Abstract: It is an object of the present invention to provide a liquid developer in which, in liquid developers for electrophotography or electrostatic recording, the adverse effect on electric resistance of the liquid developer and the electrically charged characteristics of toner particles is minimized and the dispersibility of a pigment and the dispersion stability of the toner particles are improved. The present invention relates to a liquid developer, which is obtained by dispersing colored resin particles encapsulating a pigment in an insulating hydrocarbon organic solvent by a wet-grinding method using a dispersant, wherein the dispersant is a polyester side chain-containing carbodiimide type compound formed by introducing a polyester side chain into a molecule of a carbodiimide compound through a reaction with a carbodiimide group.