GB2276700A - Automatic fluid trap and draining unit - Google Patents

Abstract

A self-contained device allows entry of fluid into the top of a gas-tight tank 4 and will then, by means of a float 5 and concentric shafts 6 and 10 assisted by toggle mechanisms 9 and 13 on the inner and outer shafts, automatically close the inlet valve 1 and open the outlet valve 2 to drain out the fluid. The float, shaft and toggle arrangement will then operate again, when the fluid level has fallen sufficiently, and will close the outlet valve and open the inlet valve. With the inlet valve open fluid can enter the unit again and the cycle is repeated. There is a bleed valve 3 to equalise the pressure inside and outside the tank to assist emptying. The toggle over-centre arrangements ensure that the valves are rapidly opened and closed. There is a filter arrangement 15 on the inlet. <IMAGE>

Description

AUTOMATIC FLUID TRAP AND DRAINING UNIT.

This invention relates to a device that will automatically and without requirement for additional power, remove fluids from pipes used to convey gaseous substances under pressure or vacuum conditions without exposing the gas to atmosphere.

Some industries convey gases laden with moisture, this moisture can present problems with the subsequent processing of the gases. Such a situation exists in the mining industry (coal) where there is currently no effective, automatic, self-powered method of removing condensed liquids from the gas system.

According to this invention there is provided an automatic fluid trap and draining unit comprising a gas-tight tank, a linked inlet and outlet valve arrangement, a bleed valve to assist emptying by equalising pressures,a float operating on an outer hollow shaft with spring toggle mechanism to accelerate movement, an outer hollow shaft operating on an inner spindle with spring toggle mechanism to maintain closing pressure on the valves during fill and empty cycles, automatic valve opening/closing when the tank is filled or drain to a specific level, powered only by the entry and exit of fluid, two (2) concentric shafts comprising an inner spindle and an outer hollow shaft, and a filter on the inlet to prevent the ingress of large and damaging pieces of debris.

A specific embodiment of the invention will now be described by way of example with reference to the accompanying drawing; Entry of the fluid, by gravity, is permitted at the start of a typical cycle by an open inlet valve 1 , the linked outlet valve 2 isclosed at this time. As the fluid level 14 rises in the tank 4 , the float 5 rises and comes into contact with an upper collar 7 on the outer hollow shaft 6 as the fluid level rises further the float now raises the outer hollow shaft and the primary toggle mechanism 9 begins to operate, at this time the opposing springs on the toggle are being compressed. When the float has raised the outer hollow shaft sufficiently the springs of the primary toggle mechanism pass the point where they are aligned and the spring force now causes the toggle mechanism to raise the outer hollow shaft independently of the effort from the float.The spring force is such that the outer hollow shaft rises very quickly and impacts on an upper collar 11 on the inner spindle 10. The force of this impact is such that the secondary toggle mechanism 13 on the spindle is overcome and the inlet valve is closed and at the same time the linked outlet valve is opened, also at the same time the bleed valve 3 is opened. Opening the bleed valve equalises the pressure inside and outside the tank to assist draining of the fluid.

The secondary toggle mechanism now holds the inlet closed and outlet open whilst the fluid is allowed to drain from the tank, as the fluid level falls so does the float and it contacts a lower collar 8 on the outer hollow shaft, the weight of the float is such that it makes the outer hollow shaft fall. When the outer hollow shaft has fallen sufficiently the springs of the primary toggle mechanism pass the point where they are aligned and the spring force now causes the toggle mechanism to lower the outer hollow shaft independent of the weight of the float. The spring force is such that the outer hollow shaft falls very quickly and impacts against a lower collar 12 on the inner spindle.

The force of this impact is such that the secondary toggle mechanism on the inner spindle is overcome and the outlet valve is closed and at the same time the linked inlet valve is opened, also at the same time the bleed valve is closed.

The cycle is now repeated indefinitely, as fluid can now enter the unit again.

The spring toggle mechanisms are similar in design and comprise a spindle linking the shaft to a trunnion, the trunnion is carried in a bracket that is in a fixed position within the tank. The spring acts between the shaft and the trunnion to give a toggle effect. Two of these assemblies are mounted diametrically opposite each other to balance the forces and obtain the desired type of motion.

The fluid enters the unit via a filter arrangement 15 in-the inlet pipe, which prevents the ingress of harmful debris.

All moving parts are within the walls of the tank, refer to drawing.

The inner spindle is located by an upper guide 16 and a lower guide 17.

Claims (11)

1. A fluid trap and emptying device comprising a gas-tight tank carrying the valve seats, an arrangement of two concentric shafts, inlet and outlet valve seals carried on an inner spindle, a toggle mechanism on each of the two concentric shafts, an annular float, inlet valve at the top, outlet valve at the bottom, bleed valve that operates in time with outlet valve, and a filter arrangement on the inlet to prevent the ingress of harmful debris.

2. Removal panel for access to all internal components.

3. A primary toggle mechanism on the outer hollow shaft that will overcome the mass of the shaft components and the resistance of the secondary toggle mechanism to operate the valves.

4. A secondary toggle mechanism on the inner spindle that will maintain the valves in the open and closed positions and will resist the mass of the components and the pressure or vacuum forces in the system.

5. A float that will have sufficient bouyancy to raise the outer hollow shaft and overcome the primary toggle mechanism.

6. A float that will have sufficient mass to lower the outer hollow shaft and overcome the primary toggle mechanism on the outer hollow shaft.

7. A bleed valve that will equalise the pressure inside and outside the tank toassist emptying of the fluid when the inlet valve has closed and the outlet valve has opened.

8. A self-contained unit requiring no power to be supplied.

9. An outer hollow shaft that acts as a slide hammer to close and open the valves accordingly.

CLAIMS continued

10. An inner spindle carrying the valves.

11. A means of guiding the inner spindle to seat the valves effectively.

11. A means of guiding the inner spindle to seat the valves effectively.

Amendments to the claims have been filed as follows

1. A fluid trap and emptying device that will remove fluids from gas pipes and vessels under vacuum (negative pressure) or positve pressure conditions, using the force of gravity as a means of power, independent of the pressure to which it is exposed (within its operating range; and will prevent fluid from leaving the unit by means of the outlet valve until a predetermined fluid level has been reached within the unit and comprising a gas-tight tank carrying the valve seats, an arrangement of two concentric shafts, inlet and outlet valve seals carried on an inner spindle, a toggle mechanism on each of the two concentric shafts, an annuiar float, inlet valve at the top, outlet valve at the bottom and a bleed valve that are linked in operation and a filter arrangement on the inlet to prevent the ingress of harmful debris and appropriate selection of the specific level of fluid required for operation will with the number of cycles known permit the volume and rate of fluid flow to be determined 2. Removable panel for access to all internal components.

3. A primary toggle mechanism on the outer hollow shaft that will overcome the mass of the shaft components and the resistance of the secondary toggle mechanism to operate the valves.

4. A secondary toggle mechanism on the inner spindle that will maintain the valves in the open or closed positions and will resist the mass of the components and the pressure or vacuum forces in the system.

5. A float that will have sufficient bouyancy to raise the outer hollow shaft and overcome the primary toggle mechanism.

6. A float that will have sufficient mass to lower the outer hollow shaft and overcome the primary toggle mechanism.

7. A bleed valve that will equalise the pressure inside and outside the tank to assist emptying of the fluid when the inlet valve has closed and the outlet valve has opened.

8. A self-contained unit requiring no power to be supplied.

9. An outer hollow shaft that acts as a slide hammer to close and open the valves accordingly.

10. An inner spindle carrying the valves.