Patent ID: 6807926
Filing Date: 2004-10-26
Classification: F01P,F04D,F16D,Y02B

Abstract:
A control method for an outside control type fan coupling apparatus of such a double valve structure that an inside of a sealed housing comprising a case which is supported through a bearing on a rotation shaft to whose tip a drive disc is fixed and a cover which is attached to the case is divided into an oil holding chamber and a torque transmission chamber in which the drive disc is mounted by a partition plate which has an oil supply adjustment hole, and a dam and a circulation flow path which is strung to this and comes over from the torque transmission chamber side to the oil holding chamber are formed in a part of an inside wall of the sealed housing side which holds the oil at the time of rotation and opposes to an outside wall of the drive disc, and a valve member for opening and closing the oil supply adjustment hole is disposed in the oil holding chamber, and made is such a system that a running torque transmission from a driving side to a driven side is controlled by increasing and decreasing an effective contact area of oil at a torque transmission gap part which is formed by the driving side and the driven side, and made is such a structure that, at the oil holding chamber side of the sealed housing, a non-excitation type electromagnet utilizing a permanent magnet is supported to the rotation shaft through the bearing, and the valve member is operated by the electromagnet and thereby, oil supply adjustment hole is controlled to be opened or closed, and a plurality of the oil supply adjustment holes are disposed, and an On use valve and a Middle use valve in which the valve member and the non-excitation type electromagnet are disposed with respect to each oil supply adjustment hole are disposed, wherein an acceleration of an engine is detected when a vehicle moves, and when the acceleration is larger than a set value, the On use valve and the Middle use valve are closed to make a fan Off rotation, and when the acceleration is smaller than the set value, engine coolant temperature is detected, and when the coolant temperature is smaller than a lower limit threshold value, an operational state of an air conditioner is detected, and when the air conditioner does not operate, the On use valve and the Middle use valve are closed to make the fan Off rotation, and when the air conditioner operates, the On use valve is closed and the Middle use valve is opened to make the fan Middle rotation, and on the other hand, when the coolant temperature is larger than the lower limit threshold value and smaller than an upper limit threshold value, the On use valve is closed and the Middle use valve is opened to make the fan Middle rotation, and when the coolant temperature is larger than the upper limit threshold value, rotational speed of the engine at that time is detected, and in case that the rotational speed is smaller than a lower limit engine rotational speed for making the fan On rotation, the On use valve is closed and the Middle use valve is opened to make the fan Middle rotation, and in case that it is larger than the lower limit engine rotational speed, the On use valve and the Middle use valve are opened, or only the On use valve is opened to make the fan On rotation, and when the engine stops, the On use valve and the Middle use valve are closed to make the fan Off rotation.