Abstract: The timing (program) cam is driven at timing speed through a gear train which includes a clutch. When a delayed start is desired the timing cam must be positioned at the start of a cycle so a lever sensing the cam position will move a tiltable jackshaft to an active position in which the worm gear on the shaft can be engaged by a manually set ratchet segment while a cam moving with the segment de-clutches the timing speed drive. The worm gear rotation drives the ratchet back to zero at which time the clutch is engaged and normal timing begins. The number of ratchet teeth engaged with the worm gear determines the length of the time delay.

Abstract: The novelty is the low cost, versatile manner of mounting an evaporator pressure regulator valve (EPR) on a thermostatic expansion valve (TXV) to provide a compact combination valve. The TXV controls refrigerant flow to the evaporator in accordance with the pressure acting below the diaphragm and the temperature influencing the temperature responsive charged space above the diaphragm. The rider pin connecting the diaphragm to the valve is hollowed out so that the bottom of the hole in the rider pin is in the refrigerant return flow path. A restrictor is placed in the upper end of the rider pin to prevent migration of condensed refrigerant to the head chamber in the event the valve is mounted upside down. A sleeve of low thermal conductivity positioned around the rider pin where it passes through the return conduit damps temperature changes and reduces valve hunting. The EPR threads into the TXV outlet.

Abstract: The four-way reversing valve is utilized in refrigerating systems for heat pump applications to interchange the heating and cooling effects of the evaporator and condenser. The three-way pilot valve controls application of high or low system pressure to the end of the chamber adjacent the large piston. The different areas of the two pistons result in movement of the slide valve to the left (both modifications) when high pressure is applied and to the right when low pressure is applied.