Fluid Dose Dispensing Apparatus

Abstract

An apparatus for dosing a fluid flow system with a treatment fluid / chemicals is described. The apparatus includes: a vessel; an inlet pipe and an outlet pipe for coupling to the system so that fluid from the system may flow into the vessel and return into the system to flush chemicals from within the vessel into the system. The vessel has a piston within it and the vessel wall defines a cylinder in which the piston moves under pressure of incoming fluid from a first position at which the vessel contains fluid to be dispensed into the system to a second position corresponding to substantially complete emptying of the vessel. The piston has a bypass passage through or around it that opens when the piston substantially reaches the second position so that fluid from the system may flow passed the piston when the piston is at the second position.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application is a continuation if part of International Application PCT / GB2011 / 001111, with an international filing date of Jul. 22, 2011 and entitled Fluid Dose Dispensing Apparatus.FIELD OF THE INVENTION[0002]The present invention concerns improvements in and relating to apparatus for dispensing doses of fluids. In one aspect it concerns apparatus for dosing a fluid-filled, eg water-filled, system with a dose of one or more chemicals / treatment fluid. The invention may have applicability to treating central heating systems with rust inhibitor liquids or applicability to a wide range of other uses including but not limited to treating fluid-filled systems as diverse as scientific or industrial laboratory flow systems, medical systems such as drips / circulatory feeds for patients or automotive / transport or other industrial flow systems wherever there is a need for dosing the fluid in the system with treatment fluids / chemicals (ie fluid ...

AI Technical Summary

Benefits of technology

This patent describes an apparatus for dosing a fluid / water-filled system with treatment chemicals / fluid. The apparatus has a vessel with a piston that moves under pressure of incoming fluid to dispense the chemicals. The apparatus has a bypass passage that opens when the piston reaches its second position to allow fluid to flow passed the piston and prevent back pressure buildup. The vessel allows viewing of the piston movement, and there is a pressure gauge to monitor the pressure in the vessel and ensure correct operation. The dose of chemicals can be easily and reliably administered with minimal wastage.

Problems solved by technology

When dealing with a pressurised central heating system the process is made substantially more difficult by the very fact of pressurization.

However, the delivery of the water and chemicals is inefficient and relies on a sufficient flow of water to have passed through the vessel to transfer substantially the whole dose of chemical into the system before the vessel and hoses can be uncoupled from the system.

For a plumber / service-engineer on the clock this can be a significant waste of his time (and the client's money).

Furthermore, this can be wasteful of water and incur extra water meterage charges for the customer.

A further set of problems arise with regard to piston-operated devices for dispensing fluids, and especially dosing or administering two or more doses of the same or different materials at least one of which is fluid (the materials may both be fluid or be one liquid and the other a solid soluble or transportable in the fluid) materials which should be unmixed / kept apart prior to or during delivery.

Existing syringes that deliver multiple materials generally do so in parallel or provide little control over mixing of the materials and generally fail to provide an effective way of dispensing two materials sequentially with a single plunger or in a staged controlled manner.

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