Provided is a throttle device including a total of two throttle units in an engine for each two cylinders, each of the throttle units having a unit body having intake air passages corresponding to the four cylinders of the engine, a throttle shaft rotatably supported by the unit body, throttle valves secured to the throttle shaft to open and close the intake air passages for the cylinders, and a motor driving and rotating the throttle shaft, in which a first motor provided in a first throttle unit and a second motor provided in a second throttle unit out of the two throttle units have mutually different responsivities to a change in rotation speed.

Cross-port air flow that improves engine fuel economy and reduces pumping losses during part-throttle operation can be implemented in various types of internal combustion engine systems using ports that interconnect the intake ports of different cylinders, thus allowing different cylinders to share combustion air. Cross-port air flow is commenced during part-throttle engine operation to disrupt the primary combustion air flow from each throttle to its associated cylinder, which reduces charge density and engine power. The engine compensates for the reduced power by incrementally opening the throttles, thus increasing the primary combustion air flow, reducing pumping losses and improving fuel economy.

An engine includes: a cylinder head that forms an intake port connected to a combustion chamber; a throttle body that is joined to the intake port and adjusts a degree of an opening of an intake passage by rotating a throttle vale around a rotation axis of a valve shaft, the throttle vale being fixed to the valve shaft; and a case that stores a drive member and supports a drive motor, the drive member being fixed to the valve shaft, the drive motor generating a drive force that is transmitted to the drive member. The case overlaps with the intake port as seen in a side view. Accordingly, in the engine, it is possible to reduce the volume of the intake passage between the throttle valve and the combustion chamber.

In at least some implementations, a throttle body assembly includes a body that has multiple throttle bores, multiple throttle valve heads received one in each of the throttle bores, at least one throttle valve shaft to which the throttle valve heads are coupled, and at least one of a fuel metering valve and a vapor separator carried by the body.

A throttle device, including: a throttle valve (13) disposed in a plurality of intake passages (12) of a throttle body (11); a throttle shaft (14) supporting the throttle valve (13); a motor (15) for driving the throttle valve (13) to open and close through the throttle shaft (14); a rotation transmission mechanism (20) interposed between the motor (15) and the throttle shaft (14); and a position sensor to detect a displacement in the rotation transmission mechanism (20). The rotation transmission mechanism (20) is disposed at a position where the first and the second throttle bodies (11f, 11s) are adjacent, the motor (15) is disposed within an installation width Ws of either one of the first and the second throttle bodies (11f, 11s), and the throttle opening degree sensor (30) is disposed within an installation width Wt of the other one of the first and the second throttle bodies (11f, 11s).

Cross-port air flow that improves engine fuel economy and reduces pumping losses during part-throttle operation can be implemented in various types of internal combustion engine systems using ports that interconnect the intake ports of different cylinders, thus allowing different cylinders to share combustion air. Cross-port air flow is commenced during part-throttle engine operation to disrupt the primary combustion air flow from each throttle to its associated cylinder, which reduces charge density and engine power. The engine compensates for the reduced power by incrementally opening the throttles, thus increasing the primary combustion air flow, reducing pumping losses and improving fuel economy.

This valve device is provided with: a body (10) that has at least one passage (11, 12) for passing a fluid and valve shaft holes (13, 14, 15); a valve shaft (20), which is passed through the valve shaft holes so as to be rotatable; and butterfly valves (30, 40), which are fixed on the valve shaft and are for opening and closing the passages (11, 12). The butterfly valves (30, 40) are disposed so as to close the passages (11, 12) on a downstream side or an upstream side of the valve shaft holes (13, 14, 15) in a flow direction of the fluid. As a result, it is possible to prevent fluid leakage and achieve effective utilization of exhaust heat in an exhaust heat recovery system.

An engine includes: a throttle body that is joined to an intake port and that makes a butterfly valve within an intake path actuate based on driving force of an electric actuator so as to adjust an opening degree of the intake path; a receptor that extends from the throttle body to a direction distant from the throttle body above a crankcase and that receives the electric actuator therein; and a supporting piece that extends from the receptor to the direction distant from the throttle body and that is supported on the crankcase. Accordingly, in the engine, it is possible to alleviate the influence of vehicle vibrations on the throttle body and actuator by enhancing the rigidity with which to support the throttle body and actuator in a simple structure.

This valve device includes a body having passages and valve shaft holes, a valve shaft passed through the valve shaft holes in a rotatable manner, and butterfly valves. The butterfly valves include first contour parts and second contour parts forming outer contour parts that are smaller than the first contour parts. The first and second contour parts are fixed to the valve shaft in order to close off the passages at positions set apart from the valve shaft holes toward the downstream side (upstream side) of the passages, and are disposed flanking a straight line parallel to the valve shaft to form prescribed outer contour parts. The body includes first seal parts with which the first contour parts are brought into contact and second seal parts with which the second contour parts are brought into contact within the passages. Fluid leakage in a closed state can thereby be reliably prevented.

In at least some implementations, a throttle body assembly includes a body that has multiple throttle bores, multiple throttle valve heads received one in each of the throttle bores, at least one throttle valve shaft to which the throttle valve heads are coupled, and at least one of a fuel metering valve and a vapor separator carried by the body.