Abstract: The apparatus is an automatic changeover system for a vehicle exhaust ventilating pipe. The exhaust pipe on a vehicle is fed into a valve which changes its output to either the conventional vehicle mounted exhaust outlet pipe or a bypass pipe low on the chassis to which a ventilating hose can easily be attached. The activating arm of an electrical switch is located at the end of the bypass pipe where it is held down by the ventilating hose when the hose is installed. Thus, when the vehicle is moved and the ventilating hose pulled off, the switch arm is released, and the switch activates a powered activator which moves the valve to close the bypass and open the output to the exhaust outlet pipe for normal operation.

Abstract: The apparatus is a device for removing vehicle exhaust gases from a building. A sealed duct is installed under the floor of a building, and the duct includes a structure for supporting and guiding a hose dolly, a part of which travels within the duct. A flat seal is formed at the top of the duct at the level of the floor by flexible overlapping flaps which are raised and separated by the shape of the hose dolly as it moves along the sunken duct. An air cooled tail pipe coupling permits a hose connection between the hose dolly and a vehicle tail pipe without damage to the hose.