Abstract: An electronic circuit for controlling the heating or air conditioning apparatus in an automobile permits the capability of heating the vehicle without the heat surges which can occur after short periods of ignition turn off and permitting manual on-off control of the heating system even if the thermostat fails. A second circuit for controlling the device activating the valve controls the flow of heating or cooling medium independently of the ignition switch and contains a timer to keep the valve closed for a predetermined time after ignition switch-off. Two limit switches are also present for permitting the valve to be set at an open or closed position independently of both the ignition switch and the timer.

Abstract: A multiple pump assembly consisting of a series of two or more coaxial pumps the first of which is invariably a radial piston pump. The shaft of the prime mover drives the first pump by way of an Oldham coupling and an extension of this shaft extends through an axial bore of the pintle in the first pump to drive the rotary element of the second pump as well as any further pump of the assembly. If the second pump is also a radial piston pump, the two pumps may but need not have a common pintle. The slide block of each radial piston pump can be adjusted to change the rate of delivery of pressurized fluid. The fluid admitting and evacuating channels in the pintle or pintles may be formed by an electrochemical process, or the entire pintle may constitute a casting. The housing for the multiple pump assembly may include a discrete annular section for each pump or a single annular section for all of the pumps and cover members at the axial ends of the single section.