FLOATING BUSH BEARING DEVICE, AND TURBOCHARGER PROVIDED WITH SAID BEARING DEVICE

摘要

The purpose of the present invention is to provide a floating bush bearing device in which pressing force on a floating bush from lubricating oil is ensured while a circumferential groove is provided through the entire outer peripheral surface of the floating bush, and vibration is suppressed, and a turbocharger provided with this bearing device, the floating bush bearing device being provided with: a rotating shaft rotatably arranged in a bearing hole of a casing; a floating bush enclosing the rotating shaft; an oil-feeding hole for lubricating oil, the oil-feeding hole opening in the inner peripheral surface of the bearing hole; a plurality of communication holes formed in the floating bush, the communication holes extending between the inner peripheral surface and the outer peripheral surface of the floating bush, and being arrayed at intervals in the circumferential direction of the floating bush; and a circumferential groove formed in the outer peripheral surface of the floating bush or the inner peripheral surface of the bearing hole, the circumferential groove passing through the openings of the plurality of communication holes or facing the openings of the plurality of communication holes, and extending through the entire outer peripheral surface of the floating bush or the inner peripheral surface of the bearing hole, and the circumferential groove having a cross-section area that differs depending on the position in the circumferential direction.