Abstract: The plunger of the pump has a hollow, depending projection at its lower end which engages the ball valve when the plunger is locked down in a fully depressed position for shipment, the projection thereby holding the ball firmly seated against the inlet to the interior of the body so as to prevent leakage should the container be laid on its side or inverted during shipment. During the down stroke of the plunger for normal operation, the product enters the tubular plunger through orifices in the ball hold-down projection, and such orifices are located on the side of the projection, separated by slender, axially extending legs so that as the product enters the projection, it is split into a plurality of turbulent streams by the legs and recombined internally of the projection, thereby imparting a mixing action to the product to aid in keeping the constituents in a homogeneous condition.

Abstract: The collar of the pump clamps the top wall of a closure against an underlying, external flange on the pump body, and although the collar is always a fixed, predetermined distance from the flange, a variety of closures with differing top wall thicknesses may be accommodated by the collar because of the yieldable nature of an integrally depending element at a lower periphery of the collar that makes the actual clamping engagement of the collar with the closure. Such element may be defined by an annular series of separate, deflectable segments around the periphery of the collar or by a continuous annular surface capable of deflecting away from the lip but maintaining forcible engagement with the top wall of the closure at all times.

Abstract: When the plunger is fully depressed, radially projecting lugs carried by the plunger adjacent its normally upper end may be received within corresponding notches in a collar through which the plunger reciprocates, whereupon rotation of the plunger in a clockwise direction moves the lugs under overhanging shoulders of the collar so as to prevent extension of the plunger until it is intentionally unlocked from the collar. A total of three lugs are utilized so as to provide three-point, stabilized retention of the plunger in its locked-down condition, and one of the lugs and its corresponding notch is smaller than the other two so that the plunger can be locked only when it is in a certain, predetermined rotative position relative to the collar aligning the down-sized lug and notch.

Abstract: The hand-operated pump has a piston which is reciprocated within the hollow pump body by a plunger which itself is reciprocated through an opening in a collar at one end of the pump body. When the plunger is in a fully extended condition at one end of a stroke, a direct seal is obtained between an annular projection on the plunger and an annular groove on the collar which receives said projection. Thus, leakage is prevented along the interface between the plunger and the collar through the opening during shipment or accidental inversion of the pump at other times.

Abstract: The plunger may be locked down after a full depression stroke so that the overall height of the pump assembly and the container with which it is associated can be significantly reduced. A special valve component loosely encircling the plunger and slidable with friction along the interior surface of the barrel is initially positioned during factory assembly in a closed position covering vents in the sidewall of the barrel, thereby blocking the undesirable ingress of liquid into the barrel above the piston should the container be laid on its side during shipment or other handling. Upon the first unlocking upstroke of the plunger to its extended position, a shoulder on the plunger lifts the valve to an open position so the vents can function properly to introduce ambient air into the container replacing pumped-out product.

Abstract: The plunger may be releasably locked in a fully extended condition against depression by an annular locking disc which receives the plunger and has a series of radially inwardly projecting, circumferentially spaced, plunger-engaging teeth snapped into a notch on the plunger. The teeth are slightly outwardly inclined in the direction of plunger extension, and stationary structure on the pump adjacent the plunger cooperates with the teeth to prevent them from being reversely flexed when depression of the plunger is attempted, thereby securely locking the same in its upwardly extended position. By gripping a tab on the disc and flexing it upwardly so as to reversely flex at least certain of the teeth, attempted depression of the plunger while the teeth are in that condition will release the plunger so that full depression may continue.

Abstract: The discharge orifice on a fine mist sprayer has a hole through which streams of liquid particles are swirled at high speeds so as to fully atomize the liquid by the time it reaches the exit end of the hole. At that location an annular launching surface for the liquid particles flares outwardly from the hole wall through a curve extending at least 90.degree. from a tangent point on the wall. As a result of this construction, the swirling streams progressively increase in diameter as they approach the exit and encounter the flared launching surface and depart at random locations from the surface to thereby produce a spray pattern of substantially circular configuration and uniform particle distribution throughout.