Abstract: A throttle device for an internal combustion engine includes a throttle body, a transmission mechanism and an opener. A relief spring is interleaved between the throttle body and the opener. A back spring is interleaved between a final stage gear of the transmission mechanism and the opener. Each of the relief spring and the back spring is formed of a torsion coil spring. One or each of the terminal ends of the relief spring or the back spring is bent in a radial direction with respect to an axis of a coil portion. The opener or the final stage gear has at least one spring support portion with an engaging recess. The engaging recess is configured to permit insertion of the radially bent terminal end and to permit movement of the radially bent terminal end relative to the engaging recess in a circumferential direction with respect to an axis of the coil portion.

Abstract: A throttle device for an internal combustion engine includes a throttle body, a transmission mechanism and an opener. A relief spring is interleaved between the throttle body and the opener. A back spring is interleaved between a final stage gear of the transmission mechanism and the opener. Each of the relief spring and the back spring is formed of a torsion coil spring. One or each of the terminal ends of the relief spring or the back spring is bent in a radial direction with respect to an axis of a coil portion. The opener or the final stage gear has at least one spring support portion with an engaging recess. The engaging recess is configured to permit insertion of the radially bent terminal end and to permit movement of the radially bent terminal end relative to the engaging recess in a circumferential direction with respect to an axis of the coil portion.

Abstract: An ejector including a nozzle communicating with a fluid inlet, a diffuser communicating with a fluid outlet, and a decompression chamber placed between the nozzle and he diffuser. The ejector is arranged to generate a negative pressure in the decompression chamber by a fluid ejected from the nozzle. A target negative pressure P in the decompression chamber is set in a range of “40 kPa<P?50 kPa”. A SD/Sd ratio between a sectional area SD of an inlet of the diffuser and a sectional area Sd of an outlet of the nozzle is determined to meet a relation: “1.20?SD/Sd?4.08?0.047P”.

Abstract: A negative pressure supply apparatus for brake booster, arranged to supply an intake-pipe negative pressure in an engine intake system to a brake booster mounted in a vehicle, comprises a negative pressure supply part communicated with a bypass passage which allows part of air flowing in the intake pipe to bypass the intake pipe and supplies the intake-pipe negative pressure to the brake booster; an air ejector part placed in the bypass passage to increase the intake-pipe negative pressure and supply the increased negative pressure to the brake booster; and an open/close device including a temperature-sensitive medium, the device being placed in the bypass passage upstream of the air ejector part and configured to open and close the bypass passage.