Fluid delivery apparatus with bellows reservoir
A compact fluid dispenser for use in controllably dispensing fluid medicaments, such as, antibiotics, analgesics, and like medicinal agents from the device reservoir which is provided in the form of a novel bellows type assembly. The fluid dispenser includes a unique stored energy mechanism which takes the form of a constant force spring member of novel design that provides the force necessary to continuously and substantially uniformly expel fluid from the device reservoir. The device also includes novel adjustable flow rate control assembly that is disposed intermediate the fluid reservoir outlet and the outlet port of the device for precisely controlling the rate of fluid flow from the outlet port toward the patient.
1. A dispensing apparatus for dispensing fluids to a patient comprising:
(a) a housing having a fluid reservoir for containing fluid to be dispensed to the patient, said fluid reservoir comprising a bellows structure having an expandable and compressible, accordion-like, annular-shaped sidewall expandable from a first contracted configuration to a second expanded configuration, said housing being provided with an inlet for permitting fluid flow into said fluid reservoir and an outlet for permitting fluid flow from said fluid reservoir;
(b) pusher means disposed within said housing for movement between a first position and a second position to cause said annular-shaped sidewall to move toward a contracted configuration and to cause said fluid contained within said fluid reservoir to flow toward said outlet of said housing;
(c) stored energy means disposed within said housing for acting upon said pusher means to cause said pusher means to move toward said second position, said stored energy means comprising a constant force spring;
(d) fill means carried by said housing for filling said fluid reservoir with the fluid to be dispensed;
(e) flow control means carried by said housing for controlling fluid flow from said fluid reservoir to the patient, said flow control means comprising:
(i) first and second selector members rotatably mounted within said housing, each of said first and second selector members having a head portion having a plurality of circumferentially spaced indexing cavities and a body portion having an axially extending passageway and a plurality of radially extending flow control channels, each having an inlet port and an outlet port, said outlet port being in communication with said axially extending passageway; and
(ii) a flow rate control member mounted within said housing, said flow rate control member having a plurality of elongated fluidic flow control channels in communication with said plurality of radially extending flow control channels formed in said second selector member; and
(f) dispensing means connected to said housing, said axially extending passageways of said first and second selector members being in communication with said dispensing means.
2. The dispensing apparatus as defined in claim 1 in which said plurality of elongated fluidic flow control channels of said flow rate control member have a depth of approximately 10-100 μm.
3. A dispensing apparatus for dispensing fluids to a patient comprising:
(a) a housing having a fluid reservoir for containing fluid to be dispensed to the patient, said fluid reservoir comprising a bellows structure having an expandable and compressible, accordion-like, annular-shaped sidewall expandable from a first contracted configuration to a second expanded configuration, said housing being provided with an inlet for permitting fluid flow into said fluid reservoir and an outlet for permitting fluid flow from said fluid reservoir;
(b) fluid displacement means disposed within said housing for movement between a first position and a second position to cause said fluid contained within said fluid reservoir to flow toward said outlet;
(c) stored energy means disposed within said housing for acting upon said fluid displacement means to cause said fluid displacement means to move toward said second position, said stored energy means comprising a constant force spring;
(d) fill means carried by said housing for filling said fluid reservoir with the fluid to be dispensed;
(e) flow control means carried by said housing for controlling fluid flow from said fluid reservoir to the patient, said flow control means comprising:
(i) a selector member rotatably mounted within said housing, said selector member having a head portion having a plurality of circumferentially spaced indexing cavities and a body portion having an axially extending passageway and a plurality of radially extending flow control channels, each having an inlet port and an outlet port, said outlet port being in communication with said axially extending passageway; and
(ii) a flow rate control member mounted within said housing, said flow rate control member being constructed from a medical grade polymer and having a plurality of elongated fluidic flow control channels in communication with said plurality of radially extending flow control channels formed in said selector member, said fluidic flow control channels being made by injection molding techniques; and
(f) dispensing means connected to said housing and in communication with said plurality of fluid passageways formed in said selector member.