Patent attributes
A pre-compression pump (10) dispenses microdoses of fluid (F). The pump minimizes pulsing due to pressure fluctuations. The pump is provided with the following to limit pulsing: a low force slow return velocity return spring (46); enlarged fluid passage (58); elastic bumper (74); and, a ratchet tooth (76) bearing against the stem (44). Further, a deflectable diaphragm (90), a splined (70) stem (44), no dip tube, and an off-center, gravitational low-point pump inlet (62) assist in priming the pump. The pump includes a stem (44) with delfectable fingers (92) to ensure sufficient momentum in pump operation. Detents (118) and grooves (120) selectively lock a nozzle cap (14) in an inoperative position. To ensure cleanliness, nozzle (60) cleaning is provided, wiping of the nozzle to remove meniscus (M) therefrom, cuts (104) formed in a shroud (98) assist in drawing excess fluid from the nozzle, and an empty volume (108) for collecting fluid run-off from the nozzle. A handle (H) is mounted to the pump providing a grip.
