GB2136104A

GB2136104A - Steel cylinder for a drink dispenser

Info

Publication number: GB2136104A
Application number: GB08404264A
Authority: GB
Inventors: Karl Hansmann
Original assignee: HAHN METALLBAU GmbH
Current assignee: HAHN METALLBAU GmbH
Priority date: 1983-02-25
Filing date: 1984-02-17
Publication date: 1984-09-12
Also published as: ZA84899B; GB2136104B; FR2541746B1; LU85226A1; DE3306626A1; DE3306626C2; GB8404264D0; FR2541746A1

Abstract

The steel cylinder is provided for a drink dispenser for introducing a gas under pressure into a liquid, in particular, for mixing water with carbon dioxide. Screwed onto the cylinder neck is a valve via which the gas can be filled into the cylinder interior along slots 13 in the screw. For withdrawing the gas a valve pin is axially displaced against the force of a spring. As a safety measure against excess pressure a bursting disk 36 is provided. <IMAGE>

Description

SPECIFICATION Steel cylinder for a drink dispenser The invention relates to a steel cylinder for a drink dispenser having the features of the preamble of claim 1.

In known steel bottles or cylinders of this type the valve is fitted to the cylinder neck at an external connecting thread. The sealing is effected by a sharp edge formed at the outlet mouth of the cylinder. To avoid damage to the sharp edge and thus leakage the assembly of the valve on the outer connecting thread of the cylinder neck must be carried out extremely carefully. At the end of the valve remote from the cylinder neck an outer thread is provided with which the valve with the connected cylinder is screwed into the drink machine. In addition, on the valve a safety means with a bursting disk is formed which is held via a securing screw which is disposed perpendicularly to the withdrawal flow path and which comprises a radial withdrawal passage and perpendicularly thereto diametrical outlet openings for the gas discharge.If for example by the action of heat the pressure in the cylinder becomes so high that a predetermined limit value of about 250 bar is exceeded, the bursting disk is destroyed and the compressed gas in'the cylinder can escape. Due to the valve screwed onto the cylinder neck a disturbingly great overall height results which correspondingly limits the volume of the steel cylinder for given space conditions in the drink dispenser. During transport of a steel bottle with the valve screwed on because of the projecting valve there is a danger of damage to the valve itself and to the unit as a whole. Also, the valve screwed into the cylinder neck comprising the laterally disposed bursting disk and the connecting thread for the cylinder neck as well as the connecting thread for the drink dispenser is necessarily made relatively large.Another disadvantage is that the securing screw is at the outer periphery of the valve and consequently' there is a danger of clogging of the outlet openings for example by soiling or dirt. In addition, due to the two connecting threads there is a danger that both when the compressed gas bottle or cylinder is screwed with the valve into the drink dispenser and also when it is screwed out, tilting can occur which can lead to unintentional detaching of the connection between the valve and the cylinder neck.

The problem underlying the invention is to improve a steel cylinder for a drink dispenser having the features of the preamble in such a manner that a compact steel cylinder unit with integrated valve and greater safety is obtained.

This problem is solved according to the invention by the characterising features of claim 1.

Preferred constructional forms and further developments as well as further advantages and essential details of the invention are apparent from the features of the subsidiary claims, the following description and the drawings, which show schematically preferred embodiments by way of example. In the drawings: FIG. 1 is a sectional side view of the upper part of a steel cylinder according to the invention with integrated valve in a closure position; and FIG. 2 is a sectional side view of the upper part of the steel cylinder according to Fig. 1 , but with the valve projecting somewhat from the cylinder neck for filling the gas cylinder with pressurised gas.

The steel bottle or cylinder 1 illustrated in the drawings is intended for use in a drink dispenser which serves for example in a household for instance for introducing carbon dioxide into water.

For this purpose the carbon dioxide is introduced into the steel cylinder 1. The carbon dioxide is thus as it were packaged under high pressure in the steel cylinder 1 which is then screwed as a whole with the valve 3 integrated in the cylinder neck 2 into the drink dispenser via the cylinder neck outer thread 4. By opening the valve 3 the CO2 is released and supplied to the liquid to be mixed.

The valve 3 is actuated by a push member in the drink dispenser. The valve 3 is mareover so constructed that refilling of the valuable steel cylinder 1 is possible at any time without problems.

Formed in the cylinder neck 2 is an inner thread 5 whose length proceeding from the end face 6 of the cylinder neck 2 is substantially exactly as long as the cylinder neck outer thread 4. At the end of the inner thread 5 facing the cylinder interior, in the neck 2 a sealing edge 7 is formed whose sealing face is aligned perpendicularly to the longitudinal axis of the steel cylinder 1 or of the valve 3. On the sealing edge 7 there rests a sealing ring 8 against which in the example of embodiment of Fig. 1 a sealing shoulder 9 of a valve screw 11 provided with an outer thread 10 and screwed into the inner thread 5 of the cylinder neck 2 is firmly pressed. It may also be advantageous instead of the loose sealing ring 8 to form a sharp edge sealing ring immediately on the sealing edge 7.

It is apparent from Fig. 1 that the valve 3 is integrated practically completely in the steel cylinder 1, i.e. the neck 2. The arrangement is such that the outer end face 12 of the valve screw 11 extends substantially in one and the same plane as the end face 6 of the cylinder neck 2 or projects only very slightly beyond said end face 6.

In Fig. 2 the valve 3 is screwed somewhat further out of the cylinder neck 2 so that between the sealing shoulder 9 of the valve screw 11 and the sealing ring 8 a free space is present. It is further apparent that the valve screw 11 comprises 2 filling slots 13. Said filling slots 13 extend from the outer end face 12 of the valve screw 11 up to the sealing shoulder 9. The filling slots 1 3 are formed as longitudinal grooves in the region of the outer thread 10 and extend parallel to the longitudinal axis of the valve. On filling the cylinder 1 the carbon dioxide passes through the filling slots 1 3 via the free space beneath the sealing shoulder 9 and an annular gap 14 between the sealing ring 8 and a projection 1 5 of the valve screw 11 into the cylinder interior.After the filling of the steel cylinder 1 the valve screw 11 is screwed into the cylinder neck 2 to such an extent that in accordance with the illustration in Fig. it bears in completely sealed manner on the sealing ring 8.

Formed in the valve screw 11 is a recess 1 6 extending from the outer end face 12 into the step portion or projection 1 5. This recess 1 6 has in the upper region of the valve screw 11 a widening 17 of correspondingly greater diameter. In the recess widening 17 there is the head portion 1 8 of a valve pin 19 constructed as push member.

Beneath the head portion 18 the valve pin 19 has a peripheral turned down portion 20 so that in this region the valve pin 19 has a smaller diameter. In the region of the turned down portion 20 a helical pressure spring 21 is provided which is supported between the head portion 18 and the bottom 22 of the recess 16. The head portion 18 projects into the recess 1 6. The diameter of the head portion 18 of the valve pin 1 9 and the diameter of the helical pressure spring 21 are so dimensioned that they are substantially equal. The head portion 1 8 and the helical pressure spring 21 are however somewhat smaller in diameter than the inner diameter of the recess 1 6 so that all round a small gap is formed for the passage of gas.

The valve stem or pin 1 9 passes with a reduced-diameter guide portion 23 through the bottom 22 of the valve screw 11 and a valve seat 24 formed on the latter and constructed as thin wall tubular extension. Between the bore wall in the valve seat and the guide portion 23 of the valve pin 19 by suitable diameter proportions a flow passage 25 is formed.

At the lower end of the guide portion 23 there is a threaded portion 26 which is screwed into a blind threaded hole of a closure member 27 constructed as closure screw. The closure member 27 comprises a sleeve-like or tubular collar 28 which engages over the valve seat 24. Within said collar 28 there is a sealing ring 29 which is traversed by the guide portion 23 of the valve pin 19 and is pressed with one end face by the force of the helical pressure spring 21 against the valve seat 24. Beneath the collar 28 the closure member 27 comprises a thread 30. The end wall 31 of the closure member 27 has an opening in the form of a bore.

Screwed over the thread 30 of the closure member 27 is a cap nut 33 having in its base wall 34 a hole 35. In the cap nut 33 there is a thin bursting disk 36 which covers the hole 35. The bursting disk 36 is disposed at a distance from the opening 32; between the end wall 31 of the closure member 27 and the bursting disk 36 at the base wall 34 within the cap nut 33 is a tubular spacer sealing ring 37 which maintains the spacing.

It is apparent that all parts of the valve 3 are made substantially coaxial to each other and disposed so that preferably an economical production on automatic lathes is possible. In addition, because of the design according to the invention the valve 3 can be made relatively small and this also reduces costs. In the longitudinal axis direction the valve pin 19 is traversed by a passage bore 38 which is coaxial with respect to the opening 32 and the hole 35.

With the steel cylinder 1 according to the invention having the valve 3 integrated within the cylinder neck 2 the necessary overall length is reduced so that the total overall length is available for a greater cylinder filling or for a shortening of the drink dispenser. In addition, the valve 3 made compact according to the invention, usually from a softer material, for example brass, is accommodated in protected manner within the cylinder neck 3. This largely eliminates any danger of transport damage. In addition, the valve 3 can be fitted very simply because only components which all lie in the screwing direction or axial direction of the cylinder 1 are provided.

Furthermore, there is the advantage that the escape path for the gas in the event of excess pressure extends only in the one axial direction and no deflection of the escaping compressed gas takes place.

Nor can any damage as with a securing screw previously disposed laterally occur. In addition, the valve 3 constructed according to the invention has the advantage that by the arrangement of the filling slots 1 3 immediately in the vicinity of the valve screw 11 the filling of the steel cylinder 1 is quicker and simpler than hitherto because the filling no longer takes place via the discharge opening of the valve 3. Also, due to the formation of the filling siot 1 3 directly at the valve screw 11 the fitting to the filling appliance itself is simplified. Since with filling through the filling slots 1 3 the gas passes over a flow path which lies outside the actual valve or discharge opening, during this type of filling the inner parts of the valve 3 are largely free from stresses so that a long operating life and high safety are guaranteed.

For withdrawal of the compressed gas in the drink dispenser the valve pin 1 9 is pressed downwardly by a push member against the force of the helical pressure spring 21. The closure member 27 with the sealing ring 29 is lifted downwardly off the valve seat 24 so that whe gas can flow through the passage 25 in the valve seat 24 upwardly into the recess 1 6 past the head portion 1 8 through the recess widening 1 7 into the drink dispenser.

Claims

1. Steel cylinder for a drink dispenser for introducing a pressurised gas into a liquid, in particular for mixing water with carbon dioxide, comprising a valve which is screwed to a cylinder neck and via which the gas can be introduced into the cylinder interior and which comprises a valve pin which for withdrawal of the gas is axially displaceable against the force of a spring, and a bursting disk as safety means against excess pressure, characterised in that the valve (3) is disposed at an inner thread (5) in the cylinder neck (2) with a valve screw (11) which has an outer thread (10) and with the valve seat (24) of which there is associated in the cylinder interior a closure member (27) secured to the valve pin (19) and with the bursting disk (36) disposed thereon.

2. Steel cylinder according to claim 1, characterised in that the valve (3) with the valve screw (11), the spring-loaded valve pin (19), the valve seat (24), the closure member (27) and the bursting disk (36) is located in the region of the cylinder interior in such a manner that the outer end face (12) of the valve screw (11) lies substantially in a plane with the end face (6) of the cylinder neck (2).

3. Steel cylinder according to any one of claims 1 and 2, characterised in that the bursting disk (36) is disposed in the discharge direction of the gas coaxially in front of the closure member (27) secured to the valve pin (19), and that the bursting disk (36) is arranged spaced in front of an opening (32) traversing an end wall (31) of the closure member (27).

4. Steel cylinder according to any one of claims 1 to 3, characterised in that the bursting disk (36) is disposed in a cap nut (33) which is screwed onto a thread (30) of the closure member (27) at the base wall (34) of said nut over a hole (35), and that between the bursting disk (36) and the end wall (31) of the closure member (27) a spacing sealing ring (37) is provided.

5. Steel cylinder according to any one of claims 1 to 4, characterised in that the valve pin (19) is screwed with a threaded portion (26) into the closure member (27) and in the longitudinal direction comprises a bore (38) coaxial with the opening (32) of the closure member (27), and that preferably in a collar (28) of the closure member (27) a sealing ring (29) is disposed which blocks the valve seat (24) and is traversed by the valve pin (19).

6. Steel cylinder according to any one of claims 1 to 5, characterised in that between a guide portion (23) of the valve pin (1 9) and a bore wall of the valve seat (24) a flow passage (25) is formed and that the valve pin (19) comprises an upper head portion (18) whose diameter is greater than the diameter of the guide portion (23), and that furthermore the valve pin (1 9) passes through a helical pressure spring (21) which is mounted in a recess (16) of the valve screw (11).

7. Steel cylinder according to claim 6, characterised in that the valve pin (19) has a peripheral turned down portion (20) in which the helical pressure spring (21) is guided between the head portion (18) and the bottom (22) of the recess (1 6) and the diameter of the head portion (18) of the valve pin (19) and the outer diameter of the helical pressure spring (21) preferably being substantially equal and to form a gap being made somewhat smaller than the inner diameter of the recess (16) the diameter of the head portion furthermore an upper end section of the head portion (18) is disposed in the region of a recess widening (17) in the valve screw (11).

8. Steel cylinder according to any one of claims 1 to 7, characterised in that at the end of the inner thread (5) facing the interior of the cylinder in the cylinder neck (2) a sealing edge (7) is formed against which a sealing shoulder (9) of the valve screw (11) is adapted to be pressed, a sealing ring (8) being disposed between the sealing shoulder (9) and the sealing edge (7) in the cylinder neck (2).

9. Steel cylinder according to any one of claims 1 to 8, characterised in that between a projection (15) of the valve screw (11) carrying the valve seat (24) and the sealing edge (7) and/or sealing ring (8) in the cylinder neck (2) an annular gap (4) is formed.

1 0. Steel cylinder according to any one of claims 1 to 9, characterised in that the valve screw (11) comprises at least one filling slot (13) which extends from the outer end face (12) to the sealing shoulder (9) and which is formed preferably parallel to the longitudinal axis of the valve screw (11) in the region of the outer thread (10).

11. Steel cylinder according to any one of claims 1 to 10, characterised in that the inner thread (5) in the cylinder neck (2) starting from the end face (6) thereof is substantially exactly as long as a cylinder neck outer thread (4).

12. Steel cylinder for a drink dispenser for introducing a pressurised gas into a liquid substantially as described with reference to the drawings.