Abstract: A valve device includes: a valve having a ball surface having a convex spherical shape, and a first opening opened in the ball surface to allow fluid to pass through; and a seat having an annular shape and opposing the ball surface to be in sliding contact, the seat being pressed against the ball surface, the seat having a second opening to communicate with the first opening. The seat has a sealing surface in a sliding contact with the ball surface at a valve closed time when the ball surface and the second opening overlap with each other, and a seat contact surface in a sliding contact with an opening inner wall surface or an opening end surface of the first opening at a valve opened time when the first opening and the second opening overlap with each other.

Abstract: A valve device includes: a valve having a ball surface having a convex spherical shape, and a first opening opened in the ball surface to allow fluid to pass through; and a seat having an annular shape and opposing the ball surface to be in sliding contact, the seat being pressed against the ball surface, the seat having a second opening to communicate with the first opening. The seat has a sealing surface in a sliding contact with the ball surface at a valve closed time when the ball surface and the second opening overlap with each other, and a seat contact surface in a sliding contact with an opening inner wall surface or an opening end surface of the first opening at a valve opened time when the first opening and the second opening overlap with each other.

Abstract: The cooling system is provided with an internal passage for circulating the cooling water inside an internal combustion engine, a water pump provided in an one end side external passage connected to the one end portion of the internal passage, and an ECU configured to execute a water flow switching control that switches a cooling water flow in the internal passage between a forward flow directed from the one end portion of the internal passage to the other end portion and a reverse flow directed from the other end portion to the one end portion.

Abstract: A valve device includes: a valve having a ball surface having a convex spherical shape, and a first opening opened in the ball surface to allow fluid to pass through; and a seat having an annular shape and opposing the ball surface to be in sliding contact, the seat being pressed against the ball surface, the seat having a second opening to communicate with the first opening. The seat has a sealing surface in a sliding contact with the ball surface at a valve closed time when the ball surface and the second opening overlap with each other, and a seat contact surface in a sliding contact with an opening inner wall surface or an opening end surface of the first opening at a valve opened time when the first opening and the second opening overlap with each other.

Abstract: The cooling system is provided with an internal passage for circulating the cooling water inside an internal combustion engine, a water pump provided in an one end side external passage connected to the one end portion of the internal passage, and an ECU configured to execute a water flow switching control that switches a cooling water flow in the internal passage between a forward flow directed from the one end portion of the internal passage to the other end portion and a reverse flow directed from the other end portion to the one end portion.

Abstract: A valve device includes: a valve having a ball surface having a convex spherical shape, and a first opening opened in the ball surface to allow fluid to pass through; and a seat having an annular shape and opposing the ball surface to be in sliding contact, the seat being pressed against the ball surface, the seat having a second opening to communicate with the first opening. The seat has a sealing surface in a sliding contact with the ball surface at a valve closed time when the ball surface and the second opening overlap with each other, and a seat contact surface in a sliding contact with an opening inner wall surface or an opening end surface of the first opening at a valve opened time when the first opening and the second opening overlap with each other.

Abstract: An engine control system includes an engine that outputs a rotation of a crankshaft through a torsional damper; a calculation portion that calculates a value of engine torque based on an angular acceleration of the crankshaft and a moment of inertia of the crankshaft; and a correction portion that calculates a correction value based on a torsional angle of the torsional damper, and corrects the calculated value of the engine torque using the correction value.

Abstract: An engine control system includes an engine that outputs a rotation of a crankshaft through a torsional damper; a calculation portion that calculates a value of engine torque based on an angular acceleration of the crankshaft and a moment of inertia of the crankshaft; and a correction portion that calculates a correction value based on a torsional angle of the torsional damper, and corrects the calculated value of the engine torque using the correction value.