Fluid handling – Self-proportioning or correlating systems – Self-proportioning flow systems
Patent
1987-11-30
1989-06-13
Nilson, Robert G.
Fluid handling
Self-proportioning or correlating systems
Self-proportioning flow systems
417345, 417394, A01C 2304, A01M 700, F04B 1302
Patent
active
048382973
DESCRIPTION:
BRIEF SUMMARY
The invention relates to an apparatus permitting the injection of a fluid into a distribution network. The invention is applied in particular for the injection of liquid or solid fertilizer, or phytosanitary products into irrigation or adduction networks, or even for the injection of maintenance solutions into micro-irrigation networks.
Several types of apparatus for meeting this objective are presently available on the market.
A first apparatus operates dosing pumps which permit injecting a quantity of solution proportional to the flow of fluid to be treated, and continuously while the fluids are available. However, these dosing pumps have a major disadvantage of requiring a supply of electricity. In effect, other than the costs of investment and exploitation, the need for a feed source of electric power makes problematic the use of dosing pumps in the many regions which are completely void of electric distribution networks. Moreover, these dosing pumps comprise a significant number of moving parts (flap valves, pistons . . . ) which are subject to premature wear and which calls for a permanent stock of replacement parts and qualified personnel.
To overcome these inconveniences, several types of apparatus operating without electricity have been developed.
The most rudimentary apparatus comprises a venturi nozzle having divergent cones inserted into the conduit system for the fluid to be treated. This nozzle creates a reduced pressure which permits obtaining, at a given level in the cone, a pressure in the piping system less than atmospheric, and may thus allow the aspiration of the solution to be injected, if the feed conduits for the solution is judiciously connected. This apparatus presents the advantage of not having any moving pieces. However, it presents two major disadvantages. First, the dilution ratio is proportional to the square of the speed of the principal fluid and not to the flow of this fluid, and is therefor not constant. This apparatus creates, furthermore, very significant pressure drops which may absorb up to 70% of the energy of the fluid to be treated. More elaborate devices have thus been developed, for overcoming these drawbacks.
One of these devices comprises a hydraulic injector for which the proportion of the solution to be injected is constant and is obtained by the alternating movement of a volumetric hydraulic piston. The cadence of the piston and thus the hourly volume of solution injected are controlled by means of a micrometer screw. This apparatus, besides its autonomy, permits injection of a solution, continuously, while the motive fluids are available. However, the quantity of fluid injected into the principal network is constant (except for the manual intervention acting on the micrometer screw) and do not take into account the variations in pressure or in flow rate of the principal fluid. Further, this apparatus comprises numerous moving pieces which are subject to premature wear.
For overcoming the first inconvenience of this apparatus (non-constant dilution ratio), there is also available on the market a proportional doser comprising a primary piston provided with two flag valves alternatively closed and opened during movement of the piston. This doser being inserted into the piping system of the fluid to be treated, the cadence of the piston is thus a function of the flow of this fluid. In other words, this piston includes in its prolongation, a small pump comprising a plunger piston which permits aspirating and introducing the treatment product into the piping system of the fluid to be treated. The strokes of the principal piston and therefor the plunger piston are thus proportional to the flow rate and the dilution ratio remains constant. However, while this type of apparatus appears to perform for installations having low flow, it presents numerous disadvantages when it is used for significantly sized installations. In effect, a large flow entails a very rapid cadence of the piston and as a result problems of wear, significant loss of pressure, and finally a poor
REFERENCES:
patent: 2653552 (1953-09-01), Geeraert
patent: 3256908 (1966-06-01), Mann
patent: 3524714 (1970-08-01), Grove
patent: 3590846 (1971-07-01), Eisele
patent: 3791768 (1974-02-01), Wanner
patent: 3815621 (1974-06-01), Robinson
patent: 4394870 (1983-07-01), Macphee
Dutton, Jr. Harold H.
Nilson Robert G.
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