Fluid Metering/Administering for Surgical Application

[MeritRD]

i'm looking for a solution that could come in one of two ways. (please excuse the lack of technical knowledge and wording.)

1. i need a normally off straight through valve that, when activated manually, will allow a given volume of fluid to pass, and then turn off again. schematics and cutaways would be very helpful.

the volume is about 3 ml the incoming tubing has an ID of about 3 mm. there is a pressure of abot 300 mm Hg (6 psi) that would be pushing the fluid when needed. the activation could be anything like a push-button or a lever.

2. the second solution (although not as desirable) would be some way of giving visual feedback for flow of a clear liquid with above sizing characteristics. maybe a ball in a chamber that goes back an forth for each ml. can anyone point me to an existing product like this?

a solution already used in larger applications (like pipes with IDs of feet or one that is actuated electronically) is still very helpful because i'm going to probably have to create my own mold to produce these things instead of buying them. we are a producer of disposable medical products, so we already mold lots of stuff. being that i probably won't be able to find something that is exactly what we need, and disposable, just seeing other solutions to this kind of fluid metering/administering in any application will help a great deal.

thanks,

dan

 

[jmw]

Three examples of possible solutions which may give you some ideas are:
1) water powered attachement for a garden hose by Hozelok; it has a dial to enter the required volume and a lever to operate the valve. Once a certain amount has passed it autpomatically closes. A bit like a kitchen timer except with a paddle or similar instead of a spring.
2) fawcet/tap in a washroom; this might be too simplistic as it can be held open but Tylors (now part of SolartronMobrey) used to manufacture a water saving valve for Africa called a "waste-not" valve. The lever operates a two part plunger where both parts lift of the seat together. The valve closes if the lever is released at any time but if held open the pluger slowly drops from the carrier to shut of the flow.
All very basic ideas and should adapt well to your application.

JMW

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[Rod23]

It sounds like you are really seeking a meter or a metering pump rather than a valve. Think in terms of a positive displacent meter, e.g., a piston. It's similar to a hypodermic with a preset stroke and an inlet with a check valve to close when "injecting".

Rod23

 

[MeritRD]

actually, i've come up with and roughly protoyped something that is pretty much what you described, but with a special "flow diverter" stopcock so that it works with one motion. the piston i used is a double-ended syringe plunger inside of syringe bodies bonded back to back. i appreciate the answer, though. if anyone is interested in what i came up with, i could post some pics or an explanation.

thanks,

dan