the pump is deactivated to avoid causing the diaphragm to take a set toward either extreme of travel when parked for an extended time one embodiment incorporates a multiple piece actuator assembly having a diaphragm sandwiched between components another embodiment uses a single piece actuator having a circumferential groove with the diaphragm having a toroid configuration and attaching within the groove application_number US 80531010 A description the present invention comprises various embodiments of a pulse pump for delivering quantities of a fluid from a reservoir to a selected site the pump is particularly well suited for dispensing a predetermined quantity of a biodegradation agent into the under floor drain lines and drain tubes of beverage dispensers in restaurants and other locations where such dispensers are typically used but may be applied to a number of other environments and industries where periodic transfer of a predetermined quantity of fluid is required fig1 illustrates the pulse pump assembly 10 with fig2 providing an exploded perspective view of the major components of the pump assembly the pump assembly 10 comprises an electric motor 12 speed reduction gear system 14 reciprocating or oscillating pump actuation mechanism 16 diaphragm assembly 18 pump body 20 inlet check valve 22 outlet check valve 24 an inlet tube connector 26 an outlet tube connector 28 connecting tubes 30 and 32 an electrical power switch e g on off switch 34 a control module 36 with an indicator light 54 a reservoir 42 and a battery holder 40 contained within a housing or case 44 pump body.