Abstract: An airless spray pump system and method for spraying a binder solution having suspended particles which are non-abrasive for coating a product therewith is described. A reservoir contains a supply of the binder solution and is continuously mixed to maintain the solution in a homogeneous state. An inlet check valve is connected to the reservoir and the check valve has an outlet port which is connected to a pump. The check valve is operated by an upstroke of a piston of the pump to draw a volume of a solution through the check valve and into the pump while the pump supplies, under high pressure, a solution in a transfer chamber thereof to a pressure control unit of a spray apparatus. When the piston of the pump is in a return stroke, it forces the check valve to close under pressure and simultaneously operates a transfer check valve of the pump to open to transfer solution into the transfer chamber and forces a portion of the solution to the pressure control unit.

Abstract: An airless spray pump system and method for spraying a binder solution having suspended particles which are non-abrasive for coating a product therewith is described. A reservoir contains a supply of the binder solution and is continuously mixed to maintain the solution in a homogeneous state. An inlet check valve is connected to the reservoir and the check valve has an outlet port which is connected to a pump. The check valve is operated by an upstroke of a piston of the pump to draw a volume of a solution through the check valve and into the pump while the pump supplies, under high pressure, a solution in a transfer chamber thereof to a pressure control unit of a spray apparatus. When the piston of the pump is in a return stroke, it forces the check valve to close under pressure and simultaneously operates a transfer check valve of the pump to open to transfer solution into the transfer chamber and forces a portion of the solution to the pressure control unit.