The present invention relates to means for connecting at least one breathing gas cylinder to a face mask or the like in breathing equipment of the kind used by firemen and divers, for instance.

Very high requirements are placed on breathing equipment of the kind normally used in difficult and dangerous circum- stances. In particular, such breathing equipment must be easy to handle and to be safe and reliable in use. Such equipment shall also be capable of withstanding rough treatment and must be flexible in solving problems that arise in emergency situations.

The breathing gas is normally obtained from a back-carried gas cylinder which when full can have a pressure of 300 bars. The equipment includes one or more pressure regulators by means of which the air pressure is lowered to an overpressure corresponding to about 25 millimeters water column when entering a face mask, mouthpiece or the like.

Depending on the type of working operation concerned, the user of the equipment will carry either one single air supply cylinder or two mutually connected cylinders, this latter in order to extend the working capacity of the equipment. When only a single cylinder is used, it is desirable to be able to quickly refill the cylinder as the need arises with the cylinder constantly connected to the breathing equipment. When using a single gas tube, it should be possible in emergency situations to connect the cylinder temporarily to corresponding breathing equipment carried by another person. When using two cylinders, the cylinders will preferably be mutually connected with the aid of a device which will permit the relative positions of the cylinders to change and enable cylinders of mutually different diameters to be used.

The main object of the present invention is to provide simple and reliable means for connecting at least one gas cylinder to a face mask or like device, said means being constructed to fulfil the aforesaid requirements, among others. The connector means shall also be relatively insensitive to external forces.

In accordance with the invention, a connector means of the kind defined in the introductory paragraph is mainly charac- terized in that it includes a three-way coupling in which at least one of the coupling connections is comprised of a hose connector which can be adjusted angularly in relation to the two remaining connections.

The fact that not all connections are fixed enables the connector means to be connected-up more easily when two cylinders are both to be connected commonly to a breathing mask. Among other things, the cylinders need not necessarily be fully parallel with one another or located at precisely the same height. The inventive connector means also enables cylinders of different diameters to be used together. Furthermore, the connector means also provides from a safety aspect the very important advantage of enabling abrupt movements of the gas cylinders to be taken up by the connec- tor means with no risk of leakage that would otherwise occur if the cylinders were to be rigidly connected together. Such abrupt movement of the cylinders may be the result of careless handling of the cylinders, for instance dropping the cylinders onto the floor so as to cause the cylinders to shift relative to one another.

When only one single gas cylinder is connected to the air supply system and the additional angularly adjustable pipe connection is intended to be used to quickly replenish the cylinder or to enable further breathing equipment to be connected to the cylinder, the ability of being able to pivot said pipe connection to a protected parking position when not

used for the aforesaid purpose is of great benefit.

Particularly advantageous embodiments of a connector means defined in the main Claim are set forth in the Claims appended thereto.

The invention will now be described in more detail with reference to exemplifying embodiments thereof and also with reference to the accompanying drawings, in which

Fig. 1 illustrates a fireman using breathing equipment which includes an inventive connector means;

Figs. 2 and 3 illustrate the inventive means in two different operational states; and

Figs. 4 and 5 illustrate the connector means of Figs. 2 and 3 from beneath and partly in section.

The fireman shown in Fig. l wears breathing equipment which includes a face mask 1 to which breathing gas is supplied through a hose 2 from two gas cylinders 3 and 4 connected to the hose in parallel. The gas cylinders are connected to the hose 2 through the medium of a T-coupling 5 having separate valves 6 and 7 for respective cylinders.

The T-coupling used includes two hose connectors 9 and 10 which project out from a tubular main body 8, see Figs. 2-5. The hose connector 10 can be adjusted angularly with relation to the other hose connector 9.

When using two gas cylinders 3, 4 in accordance with Fig. 1, each cylinder is connected to its associated hose connection 9 or 10, these hose connections then being in the positions shown in Figs. 2 and 4. Because one of the hose connectors is pivotal, i.e. the hose connector 10, the cylinders can be readily connected to the breathing air system even when the

cylinders are not fully parallel with one another -or are not positioned at precisely the same heights. The coupling means also enables cylinders of mutually different diameters to be connected together. A fixed T-coupling would not afford these advantages, but would require the use of flexible hoses to this end. The use of hoses, however, is risky because the hoses become worn and age.

Fig. 2 illustrates a manner in which the fixed hose connector 9 can be connected to the gas cylinder 4 through the medium of a coupling 11, and also illustrates a manner in which the movable hose connector 10 can be connected to the gas cylinder 3 through the medium of a further coupling 12.

Another important advantage afforded by the use of at least one movable hose connector is that the coupling means is less sensitive to careless handling. For instance, if the cylin¬ ders are dropped onto the floor while mutually connected by a fixed T-coupling, leakage is likely to occur. When using an inventive coupling means, such damage is likely to be avoided in such cases by virtue of any movement between the cylinders being taken-up by pivotal or rotary movement of the movable hose connector.

As will be seen from Figs. 2 and 3, the tubular main body 8 of the illustrated embodiment is connected to a first pressure reducer 15 through the medium of a fixed pipe connection 13 and a connection piece 14. The pressure reducer 15 is connected to the face mask 1 through the medium of a hose 16 and a second pressure reducer (not shown) , such that breathing gas will be delivered to the face mask at a pressure corresponding to about 25 millimeters water column. The reference numeral 17 identifies a conductor which can be used to deliver pressure signals and warning signals when the pressure in the gas cylinder or cylinders connected thereto falls to a given value.

The inventive coupling means has been described in the aforegoing with reference to the use of two gas cylinders. It will be understood, however, that the inventive coupling means also affords important advantages when only one cylinder is used, which is then conveniently connected to the fixed hose connector 9. The movable hose connector 10 can then be used to quickly replenish the single gas cylinder without needing to disconnect said cylinder from the breath¬ ing gas system. For instance, the movable hose connector can be used to quickly recharge the gas cylinder while briefly interrupting a working operation which will take longer to complete than the time allowed by the gas content of a single cylinder.

When using only one cylinder, the free hose coupling means enables a further face mask to be connected to the same cylinder in an emergency and when so required.

Because the free hose connector 10 is pivotal, it can be rotated to a parking position in which it is protected from external influences when not in use, see Figs. 3 and 5. This facility is highly significant, since the breathing equipment is often used under difficult conditions in which an outward¬ ly projecting hose connector of a fixed T-coupling may easily be damaged.

In the illustrated embodiment, the movable hose connector 10 can be rotated or pivoted through about 110 ^" about an axis which defines an acute angle with the longitudinal axis of the hose connector. As a result, the parking position will be located beneath and obliquely inwardly of the tubular main body 8, where it is well protected.

Figs. 4 and 5 illustrate a manner in which the coupling means 5 may be constructed to achieve the aforedescribed functions.

In the illustrated case, the hose connector 9 is fixed on the

tubular main body 8, wherein the centre passageway 18 of the connector 9 is connected to the centre passageway 19 of the tubular body by a radial passage 20.

The movable hose connector 10 is pivotal about the longitudi¬ nal axis of the main body 8, wherein the centre passageway 21 of the hose coupling means is connected with a space which surrounds the centre body and is sealed with two O-rings 22, 23 and which communicates with the central passage 19 of said centre body through the medium of a radially extending passage 24.

Because the two hose connectors 9 and 10 define an acute angle with the longitudinal axis of the main body 8, as shown in Fig. 4, two diametrically opposed hose couplings can be connected to the main body with the hose connections 9 and 10 spaced apart at an angle of 180". As described above, the hose connector 10 can also be rotated relative to the main body 8 in this position, while maintaining communication with the centre passage 19 of said main body.

When the movable hose connector 10 is not to be used, the connector can be turned through 110 ^" to the protective parking position, as illustrated in Fig. 5.

Although the invention has been described in the aforegoing with reference to an illustrated exemplifying embodiment thereof, it will be understood that several modifications can be made within the scope of the following Claims. For instance, both of the hose connectors can be made movable in relation to the main body if so desired. Furthermore, other types of swivel couplings can be used to achieve the desired mobility of one or both hose connectors.