GB1559848A - Valves - Google Patents

Description

(54) VALVES (71) We, THE BRITISH PETROLEUM COMPANY LIMITED, of Britannic House, Moor Lane, London, EC2Y 9BU, a British Company, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed to be particularly described in and by the following statement:- The present invention relates to a valve closing mechanism used for automatic sampling of liquids.

Automatic sampling techniques are preferable whenever it is necessary to take samples continuously at fixed intervals or of fixed volumes over a period of time. Conventionally, this has been achieved by mechanised means, e.g. by having the sample containers mounted on a revolving drum which is operated by a clockwork mechanism. This method is efficient especially for sampling from chromatographic analysers and such like usually installed in laboratories. However, the method requires a power source to operate the drums and/or the clockwork mechanism. In the absence of a convenient power source this method becomes uneconomic, inefficient and cumbersome if samples have to be taken from, for example, a remotely located station, e.g. a river, to monitor the extent of its pollution.

It would, therefore, be desirable to have a system which could be adapted efficiently and economically for both indoor and outdoor sampling purposes.

Accordingly, the present invention is a non-return valve for use with a container for liquids comprising a liquid inlet to the valve, a liquid outlet through the valve to the container and forming a valve seat, a float extending through and beyond the valve and being adapted to be placed in sealing en engagement with the valve seat with rise of liquid level in the container and magnetic means to hold said float in sealing engage- ment on closure, said magnetic means being a ferromagnetic armature attached rigidly to the float and positioned in proximity to a magnet at the valve inlet.

The float is suitably positioned at the valve outlet to a sample container so that when the desired amount of the sample is collected in the container, the float moves up and closes the valve against the valve seat, thus preventing further flow. The closure action is augmented by a magnetic system which prevents leakages through the valves usually found with float valves which do not form a perfect seal.

The magnet may be a permanent magnet for sampling of liquids at remote parts where no power source is available. However, if a power source is available this may be replaced by an electromagnet.

The distance between the ferromagnetic armature and the magnet is so adjusted that, prior to sampling, the armature is outside the field of influence of the magnet. When the desired amount of sample has been collected in the sample container, the buoyancy of the float in the collected sample moves the armature rigidly attached thereto in the magnetic field enabling it to be attracted by the magnet and thus closing the valve shut.

This is an important feature of the invention since valve closures operated by the buoyancy of the float alone rarely give a perfect seal due to the very gradual movement of the float in such cases. This allows attainment of an equilibrium pressure on each side of the valve which prevents complete sealing.

The valve may be formed by the float itself linking up with the mouth of the sample container like a ball and socket joint, with a stem from the float at the valve outlet extending through the valve onto the other side, i.e. the valve inlet, where it is attached to the armature.

The invention is further illustrated with reference to the drawing accompanying the Provisional Specification.

In the drawing, a receptacle (1) is provided with an inlet (9) and an overflow (10).

The armature (2) positioned in proximity to the magnet (8) but outside its field, is inserted into the valve housing (7) and is rigidly connected by means of stem (3) to the float (4) positioned inside the sample container (5). The valve housing (7) has a valve seat (6) which is matching with the shape of the float (4) to form a ball and socket joint, and centralising lugs (11) to keep the float (4) and armature (2) aligned.

The valve housing forms an air tight seal with the sample container (5). In operation, the sample enters through the inlet (9)1 and passes through the valve into the sample container (5). When the desired amount of liquid has been collected in the container, the buoyancy of the float (4) enables it to move towards the valve seat (6). This movement also brings the armature (2) into the magnetic field of magnet (8). The attraction of the armature hastens and augments the movement of the float (4) towards the valve seat (6) and closes it shut, preventing further egress of sample liquid into the container (5).Any further liquid entering the receptacle (1) from the inlet (9) is discharged through the overflow (10) which acts as the inlet for the liquid into a second sampling receptacle which is provided with its own valve, armature, magnet, float, sample container and overflow. By duplicating these units several times, the sampling devices can be used for continuous and automatic collection of samples.

WHAT WE CLAIM IS: 1. A non-return valve for use with a container for liquids comprising a liquid inlet to the valve, a liquid outlet through the valve to the container and forming a valve seat, a float extending through and beyond the valve and being adapted to be placed in sealing engagement with the valve seat with rise in liquid level in the container and magnetic means to hold said float in sealing engagement on closure, said magnetic means being a ferromagnetic armature attached rigidly. to the float and positioned in proximity to a magnet at the valve inlet.

2. A valve according to claim 1 wherein the magnet is a permanent magnet.

3. A valve according to claim 1 as hereinbefore described with reference to the drawings accompanying the Provisional Specification.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (3)

**WARNING** start of CLMS field may overlap end of DESC **. Provisional Specification. In the drawing, a receptacle (1) is provided with an inlet (9) and an overflow (10). The armature (2) positioned in proximity to the magnet (8) but outside its field, is inserted into the valve housing (7) and is rigidly connected by means of stem (3) to the float (4) positioned inside the sample container (5). The valve housing (7) has a valve seat (6) which is matching with the shape of the float (4) to form a ball and socket joint, and centralising lugs (11) to keep the float (4) and armature (2) aligned. The valve housing forms an air tight seal with the sample container (5). In operation, the sample enters through the inlet (9)1 and passes through the valve into the sample container (5). When the desired amount of liquid has been collected in the container, the buoyancy of the float (4) enables it to move towards the valve seat (6). This movement also brings the armature (2) into the magnetic field of magnet (8). The attraction of the armature hastens and augments the movement of the float (4) towards the valve seat (6) and closes it shut, preventing further egress of sample liquid into the container (5).Any further liquid entering the receptacle (1) from the inlet (9) is discharged through the overflow (10) which acts as the inlet for the liquid into a second sampling receptacle which is provided with its own valve, armature, magnet, float, sample container and overflow. By duplicating these units several times, the sampling devices can be used for continuous and automatic collection of samples. WHAT WE CLAIM IS:

1. A non-return valve for use with a container for liquids comprising a liquid inlet to the valve, a liquid outlet through the valve to the container and forming a valve seat, a float extending through and beyond the valve and being adapted to be placed in sealing engagement with the valve seat with rise in liquid level in the container and magnetic means to hold said float in sealing engagement on closure, said magnetic means being a ferromagnetic armature attached rigidly. to the float and positioned in proximity to a magnet at the valve inlet.

2. A valve according to claim 1 wherein the magnet is a permanent magnet.

3. A valve according to claim 1 as hereinbefore described with reference to the drawings accompanying the Provisional Specification.