Abstract: In a flexible pipe having upstream side and downstream side inner tubes disposed internally of a bellows tube, the interference of the bellows tube with the inner tubes is prevented and the inner opening ends of both the inner tubes are disposed in the very close proximity to each other to prevent the impingement of a fluid on the bellows tube. For this purpose, the flexible pipe includes a bellows tube 1 having bellows portions 1e, 1f on the both sides thereof with each of the bellows portions composed of ridges 1c and valleys 1d and a straight tube portion 1g formed at the center of the bellows tube 1 in the longitudinal direction and having a diameter expanded to substantially the same diameter as that of the ridges 1c. The, the inner opening end 2d of one of inner tubes 2 and the inner opening end 3e of the other of the inner tubes 3 are disposed within a range of the straight tube portion 1g of the bellows tube 1 and face each other in close proximity to each other.

Abstract: A diesel engine comprising an intake passage in which a turbocharger and a mechanically driven charger are arranged. A bypass passage bypassing the mechanically driven charger is provided, and a bypass valve is arranged in the bypass passage. When the engine is started, the mechanically driven charger is operated and the bypass valve is closed. When the engine is operating under a partial load after completion of the warm-up of the engine, the operation of the mechanically driven charger is stopped and the bypass valve is opened.

Abstract: An idling rotational speed control device wherein, when an engine ignition switch is turned off, an air flow rate control device is driven to a fully closed position or a fully opened position, and the air flow rate control valve is controlled referenced from the fully closed position or the fully opened position as the new reference position. During idling, the flow rate of air taken into an intake manifold is controlled by the intentional opening degree from the reference position of the air flow rate control valve so as to correctly perform control.

Abstract: An adjust screw device for use with a carburetor of an internal combustion engine having stops for restricting the range within which the automobile user can readjust the idle R.P.M. by adjusting the adjust screw at the carburetor. The adjust screw device is composed majorly of a first adjust screw having a large adjustable range and a second adjust screw for fine adjustment, the physical position of the second adjust screw being changed by the adjustment of the first adjust screw. After initial adjustment of the first adjust screw by the manufacturer, further adjustment of the screw is completely blocked and the second adjust screw is then adjustable by the user only over a predetermined range.

Abstract: A construction for protecting a member, such as an adjusting screw or fixing bolt, fitted to a base, from being tampered with, including a wall formed generally in the shape of a hollow tube, attached by one of its ends to the base, and surrounding the member to be protected, and a plug inserted into the other end of the wall so as to be wedged into it, with a slot being formed in the wall, extending along the axial direction of the wall from the end of the wall remote from the base, to a slot bottom at an axial position between the free end of the wall and the base, the slot bottom being closer to the base than is the part of the plug which is closest to the base, so that a gap is left between the bottom of the slot and the bottom wall of the plug for a removing tool to be inserted to lever the plug out of the end of the wall.

Abstract: A fuel pump for an internal combustion engine including a casing wherein partition walls divide the upper space of said casing into a fuel drawing chamber receiving fuel from a fuel tank, a fuel chamber discharging the fuel to a carburetor and a vapor separating chamber communicating with the fuel tank. A space between the fuel chamber and the vapor separating chamber enables the communication of the fuel chamber with the vapor separating chamber, so that a large portion of the vapor produced in the fuel chamber removes to the vapor separating chamber and can be returned to the fuel tank, with the result that fuel substantially free from vapor can be supplied to the carburetor.

Abstract: This discloses an ignition timing adjusting system for spark-ignition internal combustion engines, which realizes an advance in ignition timing in relation to altitude or vertical height at which an engine is operating. This system comprises vacuum advance means responsive to a vacuum produced by the vacuum in the intake tube of the engine for advancing the ignition timing of the engine, and means for controlling the level of said vacuum produced by said intake tube vacuum in relation to the engine operating altitude. When the engine is operating at a higher altitude than that for which the ignition timing was originally set, the timing is advanced, under control of said vacuum level controlling means, to a position which is proper for the operation of the engine at such an altitude.

Abstract: Disclosed is an apparatus having an air control valve for introducing an amount of air into the intake system of an internal combustion engine when the engine begins to decelerate, for preventing after-fire of an unburnt air-fuel mixture in the catalytic converter arranged in an exhaust pipe of the engine. The apparatus further includes a temperature detecting valve adapted for stopping the operation of the flow control valve during engine warm-up operations. Therefore, introduction of air into the intake system is stopped even if the engine begins to decelerate and, also, a proper engine warm-up operation can be carried out.

Abstract: A throttle positioner to ensure a predetermined minimum opening of a throttle valve when an engine is abruptly decelerated from a relatively high speed condition, said positioner being adapted to be switched over between operating and non-operating conditions by alternating the introduction of intake tube vacuum or atmospheric pressure into a diaphragm means, wherein a combination of a check valve and constricting means is provided to optionally determine the time constant of said switching over operation.

Abstract: In an automatic choke valve for an internal combustion engine the extent to which the choke valve is opened is controlled by a bimetal member located in a casing separate from the carburetor through which air is passed whose temperature is determined by the temperature of the engine. In addition, a heater unit is positioned in the casing for supplying heat to the bimetal member and the heater unit is controlled by switches operated by the engine temperature and by the atmospheric pressure around the engine.

Abstract: A carburetor for minimizing the variation in the ratio of fuel contained in the fuel-air mixture due to fuel evaporation within the float chamber. The carburetor has an air passage providing communication between the float chamber and the air intake pipe at a location upstream of the throttle valve. A further air passage provides communication between the float chamber and the air intake pipe at a location disposed downstream of the throttle valve, which further air passage contains a throttle therein for controlling the flow therethrough.