Abstract: Complementary couplers useful in providing a coupling through which liquids may be transferred from a first storage reservoir or tank to a second storage reservoir or tank, which can be an on-board fuel tank of a motorized vehicle. There is a first coupling which is configured to be in fluid communication with the interior of a receiving vessel, fuel tank, etc. and a second coupling which is intended to be in fluid communication with the contents of a storage reservoir containing a chemical, liquid fuel, etc. The disclosure also includes a process for charging a fuel reservoir on board of a motorized vehicle from a remote reservoir, wherein the vapor in the fuel reservoir is displaced by an equal volume of fuel delivered from said remote reservoir, and wherein the vapor in said fuel reservoir is simultaneously caused to be transferred to said remote reservoir, thus permitting no escape of the vapor from said fuel reservoir to the surrounding atmosphere.

Abstract: Provided are nozzles useful for controllably transferring any fluid including without limitation liquids such as hydrocarbon fuels from a first reservoir to a second reservoir. Dispensing nozzles as provided herein have several advantages, including increased control by the technician who is transferring the fluids over the nozzle itself by virtue of greater physical control and less operator fatigue. In addition, a small amount of force applied to the dispensing lever results in a relatively large opening of the control valve mechanism. Further, when line pressure is zero or near zero, it is not possible for un-metered fluid leakage to occur, which provides cost advantages to large volume vendors of liquids such as hydrocarbon fuels which are dispensed on a routine basis, such as at airports. Safety is also greatly enhanced, since latent quantities of fuel cannot flow out from lines equipped with the nozzles provided when supply lines are not pressurized.

Abstract: Complementary couplers useful in providing a coupling through which liquids may be transferred from a first storage reservoir or tank to a second storage reservoir or tank, which can be an on-board fuel tank of a motorized vehicle. There is a first coupling which is configured to be in fluid communication with the interior of a receiving vessel, fuel tank, etc. and a second coupling which is intended to be in fluid communication with the contents of a storage reservoir containing a chemical, liquid fuel, etc. The disclosure also includes a process for charging a fuel reservoir on board of a motorized vehicle from a remote reservoir, wherein the vapor in the fuel reservoir is displaced by an equal volume of fuel delivered from said remote reservoir, and wherein the vapor in said fuel reservoir is simultaneously caused to be transferred to said remote reservoir, thus permitting no escape of the vapor from said fuel reservoir to the surrounding atmosphere.