The present invention refers to filling valves, intended for the filling of gas tubes or containers with gas from compressors or pressure containers, however, preferably from air compressors wit connection to the compressor unit by means of the inlet of the filling valve.

Hitherto needle valves have been used at the filling of gas containers. Gas containers of this kind often are such ones that are used by the personnel in the fire brigades, which for their firemen equipped with smoke helmets among other things, use respirators connected to the gas containers. The air, or in case the gas mixture that is used for breathing purposes, must be completely dry as well as completely clean.

The filling of gas containers is a daily work taking place at filling stations and the demand for rapidity and safety iji the- filling operations must be set high. The demands for safety of the service personnel, handling the containers or the tubes at the filling rampes, must as well be consider¬ ed, so that damages do not occur on individuals and mater- ials, owing to not reliable valves. It is important that for exemple, at hose breaks, at the filling of gas under pressures, the risk of damages can be eliminated.

Needle valves, which have been used at the filling of air on gas containers, have a tendency to be worn too fast, and in that case principally in the threads, resulting in un¬ acceptable untightness.

A needle valve provided with threads demands for its goor function at the opening- and closing moments that soπe l.ind of lubricating takes place, otherwise the threads will seize. When the valve is forced to function in dry air, not having any lubricating properties, a too fast worn out of the valve takes place, and the valve will become unuseable. As a con¬ sequence thereof, it will be large costs for the replacements of needle valves, as their lifes are too short. For a filling operation, two needle valves are necessary to use. As safety

in the filling operation is an essential demand, and the draw¬ backs with initialed leakage already after approx, 200 fil¬ ling operations are evident, it is important to find a better technical solution of the problem to fill gas containers. To use other types of valves, intended for the filling of other mediums then air, for exemple, filling valves for lique¬ fied petroleum gas are not poεrsible. The Swedish patent spe¬ cification number 350 824 that just relates to such a valve, does not prove to show such constructional features and em- bodiments that are demanded, as it has a ball-shaped valve body, and without small seat- and cone areas, which are neces¬ sary at work with high pressure. This filling valve has no simi¬ larities in other respects with the filling valve according to the invention, as it furthermore is intended for the filling of liquefied petroleum gas and not for the filling of dry gas, as for exemple air.

Also other technical solutions as ball valves provided with throttle nozzles hav been tested at the filling of air in tubes and containers. In this case, however, it is necessary to use two valves of that kind for the filling operation. This contri¬ butes to the fact that the work turns to be heavy as it results in a number of hand grips.The working moments do not either come in a logical succession, obviously being a drawback.

The life is not either especially great, but better than for needle valves. The valves function up to approx. 1000 filling operations.

With the knowledge about the drawbacks associated with valves of said kind, the filling valve according to the invention has been designed according to other "outlines. When it concerns to meet, the demand for reliability, it is essential that no parts are worn out quickly and unpredictable. As the valve will work under high pressure, great forces will be transferred to valve cones and seats included. It is an object of the invention to eliminate this drawback. Within the frame of the invention this is solved by means of giving small dimensions to the tightening seats and the contact surfaces, so that the parts of the valve

do not be loaded with two great forces at high pressures against these surfaces.

At the same time, the valve is intended to be smooth and ea¬ sy and simple to handle manually. With the filling valve ac- cording to the invention, this is possible by means of the working operations: opening, closing and venting, taking place in a logical .succession at a filling ramp for a number of containers or tubes.

It is essential that the working operation runs quickly with- out the risk for error in the manoevering of the valve, and that closing and exchange of gas tubes can take place con¬ tinuously. If risk exists for hose break, for exemple, at over-filling of containers with gas under pressure being high, or by other reasons, hose breaks occur, the present valve can allow that the air flowing from the compressor will have a reduced velocity of discha ge, by means of a ^• throttle nozzle put in the inlet port of the valve. At hose break, otherwise the piece of the hose that conveys the high pressure (working ^' pressure 300 bars) of ^' compressor air would "whipe" around, a ^* nd make it difficult for anyone of the ser¬ vice personnel to reach the shut-off cock at the ramp, with¬ out being damaged by the hose. As a hose break cannot be pre¬ dictable, it can happen that service personnel, that quite naturally must stay near the filling valves, completely un- prepared will be hit by a "whiping" hose stump or piece of hose at hose break. This has happened in practice, and a stroke from a hose under high pressure can give damages on the person being hit.

The valve completes in a way of safety the system, in which it forms a part, viz. that which includes a sliding filling coupling with a safety valve for hose breaks in the form of a resetting valve provided between the gas container and the filling valve. The resetting valve allows, however, that a small flow of approx. 50 litres per minute can pass at vent- ing, and discharges, under these circumstances, the filling valve and the coupling attached to the container or the tube

An object of the present invention is to achieve a valve that eliminates in high degree the inconveniences that are evident at known valves, in the respect that it has a longer life, and in connection with this a better safety in function. This is achieved by means of a filling valve that according to the invention has the features stated in the accompanying claims.

Within the frame of the invention the valve can be connected to a compressor, but at the filling of a number of containers simultaneously, it is to prefer that a filling valve needed for each container is connected to a ramp, which has a common feeding conduit from a compressor. Necessary manometers are connected to the valve by practical reasons for measuring of the current pressure used at the containers in question. These and other details and advantages characterizing the in¬ vention will be explained closer with reference to the at-, tached drawings, that show- the filling valve inserted in its context, and the d ^' iffere-nt- positions that included movable components will take at opening,- closing- and venting occa- tions.

Fig. 1 shows schematically a picture of a filling operation with gas on a container.

Fig. 2 shows partially in section a filling valve in closed position, but still under pressure, if not venting has taken place in an earlier moment.

Fig. 3 shows partially in section the filling valve in an opening position.

Fig. 4 shows partially in section the filling valve in a vent¬ ing position. The valve showed in Figures 2 - 4 has a valve housing 10 com¬ prising a solid body of metal. An inlet 11 for threaded con¬ nection 42 to the compressor conduit is provided in a valve body 43, threaded to the lower part of the valve housing. An outlet 12 for compressed air from compressor is provided in the side of the valve housing, and is in connection with a gas container by means of a threaded attachment- and hose coupling

and hose coupling.

In the end of the valve housing, faced opposite to the inlet 11, a piston housing 26 is provided, as an opening for an ope¬ rating piston 22, that opening being circular, and formed to a straight piston bore 25, extending some length into the val¬ ve housing. In the bottom of this piston bore 25, in the cent¬ re of the bottom, a circular opening passage 27 is provided for a spindle 28, which up to approx. 2/3 of its length is hollow drilled with a channel 28A for the passage of venting air.

In the lower part of the piston bore, in its wall, i.e. in the piston housing 26, a circular channel opening 13 is provided perpendicular out to the side facing from the outlet opening 12 of the valve housing 10, whereby this channel convey ven- ting air out from the valve housing via a threaded opening provided in the valve housing, to which opening a fitting 15 is connected, coπiprrsing a noise-suppression device including a sinter filter 14, through which venting air can pass out in the open atmosphere, and this without unpleasant noise for the service personnel.

The operating piston 22 is displacable in its bore by means of a pivotable lever 16 arranged straight above the operating piston. The lever 16 can be set i _ three distinct positions by manually be moved to pivoting around its fixed pivot C, ar- ranged in a plane perpendicular to the vertical plane, A fixed pivot 18, arranged in this plane, runs through a through hole, oriented in the end of the lever being in contact with the o- perating piston 22, so that the centre of the trough hole co¬ incides with the fixed pivot C. The lever is so attached on the pivot 18 that a moving of the lever can take place, with freedom from play, into three distinct positions ifi the ver¬ tical plane. These positions are set, when a cam 17, shaped at the end of the lever, for cam-controlling, is in contact with the horizontal top-surface of the operating piston 22 in a con* tact position, corresponding to venting, with the land surface 19 of the cam 17, and in shut-off position and in filling po¬ sition resp. , when cam 17 is in contact with the top-surface of the control piston with the land surfaces 20 and 21 respec-

tivel .

The operating piston 22 has, in its end faced from the top- surface, a plate enclosed in that end, in the centre of which a valve-point 23 has such dimensions that it fully tightens against the small seat 24, arranged at the upper end of a spindle 28 that is displacable into the bottom of the piston bore 25, through the passage 27. It is essential that the contact surfaces between valve-point and seat are small, and do not give rise to the fact that great forces at high pres- sures will arise and wear on included part in the valve. Re¬ peated contacts beween the surfaces at daily and several fil¬ lings demand that the material in the valve-point and spind¬ le seat has good resistance to wear in combination with good assumptions to fit-up tightened against each other. The spindle 28 extends down into a channel centrically lo¬ cated in the centre of tfte. valve, so that said channel is in alignment with and meets the channel 40, arranged in the valve body 43 for the inflow of compressor air, and the con¬ tinuation of said channel 40 in the cone bore 39. In the bottom of the drilled hole 28A a through hole of 1 mm in diameter is arranged, perpendicular to the spindle wall for the inflow of air, which wall pass out from the cavities of the valve after closing of gas container and out from the inflow channel connected to the threaded coupling attach- ed to the spindle 28, facing down against the inflow channel, transforms into a solid part and has a somewhat smaller dia¬ meter . The end of the spindle extends to a position, which is located in such adjusted distance to the top of the cone 37, that at the position of the lever for closing, the end of the spindle has sufficient play to the top of the cone that a furthermore displacement of the spindle, correspond¬ ing an opening position, the spindle end pushes against the top of the cone, and against the action of the spring 38 in the cone bore 39, and thereby presses down the cone 37 enough to create necessary free passage of compressed air from the compressor through the valve seat 36.

The solid lower third part of the spindle 28 passes through a hollow, lose circular washer" 30, which is fitted-up against the end surface 30A of the spindle and there serves as sup¬ port for the resetting spring 32. This resetting spring is carried over the solid end of the spindle and has its oppo¬ site support in the valve seat 36 of the cone 37. The washer 30 is located in a guiding sleeve 31, surrounding the lower part of the spindle 28, just before this is transformed into a smaller diameter. Above the guiding sleev 31, which is penetrated by the spind¬ le 28, a circular hollow sealing element 33 is arranged and said sealing element seals direct against the envelope sur¬ face of the spindle. The valve seat 36 is closely connected to the valve body 43 by means of a gasket ring 34.

It is important that sealing elements, and especially the sealing element 33, have long life and a surface enough-re¬ sistant to wear. Such an element has been found in a sealing ring of teflon "with selflubricating properties, which makes it possible to reach good function.

In the inlet 40 for compressed air a throttle sleeve 41 is arranged, through which air passes into during the filling operation carried out with an appropriate filling velocity. This is achieved by means of setting the diameter of the channel of the throttle sleeve to 1,6 mm.

For the passage of compressed air into the gas container a connection channel 44 is arranged in the outlet opening 12 of the valve housing 10, wherefrom it concentrically extends perpendicular to the channel, wherein the solid part of the spindle 28 together with the resetting spring 32 are dis- placeably arranged.

The filling of gas tubes with gas from compressor takes place by using the filling valve according to the invention in the following manner.

In the starting point of the filling operation the lever 16 is placed in its centre position. The gas container, which

still is unopened, is coupled to the outlet 12 via a valve reducing the effects of hose breaks, in the form of a check valve, and the connection of the inlet 11 of the valve to a feeding conduit of the compressor is made by means a conven- tional threaded fitting attachment in a reliable way. (Fig.l).

The cam 17 of the lever with the land surface 20 pushes down the operating piston" 22 inclusive the valve-point 33 to tigh¬ tened fit-up against the valve seat 24 of the spindle 28. At the same time the spindle is displaced a short distance down. A play arises according to Fig. 2 between the narrow part of the spindle, in that the upper wall section being part of the guide channel of the spindle in the filling valve. By the ac¬ tion of the resetting spring 32 against the spindle 28, via the washer 30 and the fixed support of the resetting spring against the land surface of the valve seat 36, a sealant blocking of the concentrically channel, drilled hollow takes place at the seat 24.

The valve of- the gas container will now be opened and sets the filling valve under pressure with remaining pressure from the container, if any, but the hollow drill ^' ed channel still is sealingly blocked as mentioned above, and the teflon ring 33 seals between the envelope surface of the spindle and the wall of its guiding channel.

The lever 16 is moved to opening position for filling of air on the gas container, and the control cam 17 contacts with the land surface 21 and pushes thereby piston and spindle further a short distance down in the replacement channel of the spindle to a contact with the solid spindle and against the valve cone 37, which against the ^" action of the resetting spring is moved from its sealing position in the valve seat 36 and allows free passage for compressed air to flow in and fill the container via the valve cone bore, the cavity of the resetting spring 32 and the connection channel 44 to the con¬ tainer . When the container is filled to desired pressure, the lever 16 again is moved to the middle position, a shut-off position for the filling valve, by means of the spindle that returns

to closed position by assistance of the force of the resett¬ ing spring 32, and by that a displacement is achieved upwards of that spindle, which now again seals against the valve point 23. Simultaneously with this, the fit-up pressure against the top of the valve 37 is discharged, when the end of the spindle is displaced up from the channel of the seat 36. The valve cone 37 returns to ^' closed position by means of the resetting spring 38 and the compression pressure.

The valve of the gas container is closed and the lever is mo- ved to venting position, so that the contact of the cam 17 against the operating piston 22 will be changed, by that the land surface 19 will be contacted and the operating piston 22 will be pressed upwards by the remaining pressure in the val¬ ve.The valve point 23 leaves in consequence hereby the seat 24. The admitting port 29 and the hole 28A drilled hollow will then be in communication with the inlet- and outlet channel 44 of the gas container, and the included air, between filling valve and gas container, is vented to- he atmosphere via the venting channel 13 and the sound damper 14. The throttle nozzle 41 in the inlet 11 of the filling valve allows appropriate filling velocity as mentioned, but also allows that it protects against too rapidly discharged gas, if for exemple, break of hose takes place a A according to Fig. 1. At the filling of a number of containers at the same time from a ramp the valve of the gas container is left open, if time not permits shut-off. By this, over-filling of the rest of the containers is avoided. The valves are closed first when all the containers' have been filled.

The present invention makes it possible to achieve safety for the service personnel and reliability in the function of the valve that practical tests during quite a long time ha¬ ve proved. At demonting and measuring of dimentions of mov¬ able components, no noticeable wear has been possible to ob- serve after approx. 10 000 working cycles by the valve accor¬ ding the invention.