Abstract: A suction apparatus seal for portable paint spray guns having a suction apparatus received via mating conical surfaces in a salient inlet port, the seal formed of resilient, low-density polyethylene and having a radially inwardly directed lip sized to seal around the suction apparatus and a cylindrical mediate section sized to seal around the salient inlet port and a radially outwardly flared flange to aid in installing the seal on the inlet port of the spray gun. The seal also provides positive engagement of the suction apparatus when it is initially loosely engaged with the paint inlet of the gun.

Abstract: A twin tube locking assembly for a hand-held spray gun using an extended suction set of a hose and fitting the assembly including a ring having a body with a cylindrical skirt portion and a planar wall retaining a flange of the fitting of the suction set to a pump housing of the gun. The ring is positionable to a first position permitting engagement and disengagement of the ring to the pump housing and a second position retaining the extended suction set to the pump housing by the interaction of a margin of a fan shaped aperture in the planar wall of the ring urging a flange of a fitting of the extended suction set towards the pump housing when a plurality of lips on the housing engage and retain respective lugs on the ring. A detent member on the ring is movable past a stop member on the housing to secure the ring in the engaged position. The planar wall is deformed when the ring is engaged with the housing to secure the fitting against the housing.

Abstract: An improved check valve assembly of the type having a relatively flexible disc member retained between relatively rigid inflow and outflow housing portions. The inflow and outflow housing portions are removably threadably interengaged to permit serviceability of the check valve and the relatively flexible disc member has a generally perpendicular stem extending into the bore of one of the housing portions to avoid misalignment of the disc with the housing. A tongue and groove means circumferentially seals the housing portions together by deforming to a common taper angle between the tongue and groove to provide sealing therebetween.

Abstract: An improved shaft sealing ring for a portable paint gun of the type having an axially movable control shaft for controlling a supply of pressurized air to atomize a stream of paint. The sealing ring has a truncated frustro-conical surface tapering from a radially extending retaining surface toward a front end of the sealing ring and a radially extending flange at a back end of the sealing ring with an outer peripheral groove in an outer surface of the ring body between the flange and the retaining surface. The ring is installed by urging the front face through an opening having a diameter smaller than that of the face, the opening defined by a wall extending radially inwardly as a part of the gun housing. The flange is resiliently deflected to form a seal when the ring is installed. A central bore of the seal is sized to receive the shaft with a seal between the shaft and the ring provided by a ridge extending radially into the bore of the ring at the back end thereof.

Abstract: An improved control shaft seal and air valve for a portable paint gun with the seal having a radial clearance with the shaft except at a shaft sealing surface of limited axial length. The shaft seal has a conical surface radially outward of the shaft sealing surface to provide a sealing surface and also to provide transfer of axial forces at that surface to a radial direction to provide a force to urge the shaft sealing surface against the control shaft. A second conical surface of the seal provides for retention of the seal on an air valve spring when the paint gun is disassembled. An improved air valve for portable paint guns is also disclosed having a rigid axial hub and radial support carrying a relatively flexible rim portion adapted to engage a tapered seating surface in the gun.