Abstract: An exhaust system for a motor vehicle internal combustion engine is described in which the lower end of the exhaust manifold (10) and the upper end of the down pipe (12a, 12b) each comprise two or more conduits which are sector shaped in cross section and are arranged to form a complete circle split by radial walls. The circumference of the down pipe is sealed by a flexible ball joint (14) against the circumference of the manifold (10) and the radial walls (16c) of the down pipe (12a, 12b) are spaced from the radial walls (10a) of the manifold by a small gap sufficient to permit pivoting of the down pipe relative to the manifold. The down pipe (12a, 12b) is urged against the manifold (10) by clamping bolts (20) the heads of which are pivotable relative to the exhaust system about an axis passing through the pivotal center of the flexible ball joint.

Abstract: A pressure operated valve is arranged so that it switches over rapidly between two opposite end positions. The valve has a pressure chamber closed by a diaphragm. Between the diaphragm and the valve member, there is a snap-action spring which continues to hold the valve member in one end position during a first phase of diaphragm movement, and at a preset point snaps over to a condition where it accelerates the valve member into its opposite end position, and holds it there. A biasing spring may oppose the force exerted on the diaphragm by pressure (normally vacuum) in the pressure chamber. The valve has use in EGR systems, as well as engine decelerating systems.

Abstract: A engine intake system includes a deceleration valve (10) which is biased in one direction by idle vacuum and in the opposite direction by manifold vacuum. Idle vacuum is admitted to and stored in a pressure chamber (30) in the valve each time the engine idles. When the engine is not idling, manifold vacuum is admitted to another pressure chamber (28) in the valve. A diaphragm (24) separates the two chambers and is connected to a valve member (18) which opens and closes the deceleration passage (12).

Abstract: A vacuum limiting arrangement uses a three-port, two-position valve in conjunction with a vacuum sustaining valve to limit the vacuum applied to a vacuum driven device. A source of vacuum, such as engine intake manifold vacuum, is connected to one of two end ports. The device is connected to a central port, and the other end port is vented. The device can thus be connected either to the vacuum source in one position of the control valve or to vent. A control port that is effective to switch the control valve is connected into a vacuum line between the control valve and the device. The sustaining valve allows free flow of air from the device to the control valve, but only a restricted flow in the opposite direction to provide a hysterises to the system for controlling the shifting of the control valve, which is accomplished automatically as a function of the vacuum level at the device and in the control port.