GB1587607A - Protective breathing apparatus - Google Patents

Description

(54) IMPROVEMENTS IN OR RELATING TO PROTECTIVE BREATHING APPARATUS (71) We, AUERGESELLSCHAFT GMBH, a German Body Corporate, of 1-11 Thiemannstrasse, 1000 Berlin 44, Federal Republic of Germany, 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 protective breathing apparatus for two-way respiration, of the kind comprising a heat exchanger connected to a breathing hose, a canister connected to the latter which is filled with a chemical which generates oxygen, a breathing bag which encloses the breathing hose and which is arranged above the canister, and a second canister, enclosing the first canister, which second canister is connected to the breathing bag.

Hereinafter such breathing apparatus will be referred to as "of the kind described".

Apparatus of the kind described is already known which has a breathing bag which is arranged between a jacketed chemical canister and the connection to the mouth. With this known design, complicated connections are required for the functional units of the apparatus which have to be connected to one another, firstly to connect the connection to the mouth and its breathing hose to the chemical canister and secondly to connect the breathing bag to the jacket of the chemical canister. Thus, in the known design two connections are required to connect up the jacket of the chemical canister and one connection to connect up the chemical canister itself.It is clear that the breathing bag, which has to be provided with three connections, very much complicates the construction of the protective breathing apparatus as a whole and that in addition, because of the connections at three points between the breathing bag and the jacket of the chemical canister and the chemical canister itself, the bag makes construction complicated as far as assembly is concerned.

It is an object of the invention to provide a protective breathing apparatus of the kind described which allows the breathing bag to be connected to the second canister by providing the breathing bag and the second canister with only one connecting point each.

Accordingly the invention consists in protective breathing apparatus of the kind described, wherein a first connecting nozzle is arranged at the top of the second canister, said connecting nozzle acting as a connector between the breathing bag and the second canister, a second connecting nozzle, having an opening therethrough being arranged inside and concentric with the first connecting nozzle to act as a connector for the breathing hose and the chemical canister, a space being formed between the first connecting nozzle and the second connecting nozzle, and wherein a plurality of openings is provided in the part of the wall of the second canister between the first and second connecting nozzles at a suitable distance from one another.

The advantages achieved by the invention are in particular that the breathing bag and the second canister are connected together via only one connecting point each, so that in this way on the one hand the production of the breathing bag and the jacketing of the chemical canister are simplified and on the other hand instead of two connections only one has to be made and sealed. In addition to this, the breathing hose, which passes directly through the breathing bag, does not need to be sealed.

In order that the invention may be more clearly understood reference will now be made to the accompanying drawing which shows one embodiment thereof by way of example, partly in section and partly in plan.

Referring now to the drawing, the protective breathing apparatus shown comprises in essence a chemical canister 6 which generates oxygen, a second canister 1 in which the first canister 6 is inserted and which thus forms a kind of jacket therefor, a breathing bag 3 whose upper part is connected to a heat exchanger 11 and whose lower part is connected to the canister 1 and enclosing a breathing hose 5 whose lower end is connected to the canister 6, and a breathing hose extension 13 having a mouth piece 14, which is similarly connected to the heat exchanger 11 via a socket as shown.

To enable the breathing bag 3 and the breathing hose 5 to be connected to the canister 1, tubular connecting nozzles 2 and 4 are formed at the top of the canister 1, nozzle 4 being arranged inside and concentric with nozzle 2. This arrangement of the connecting nozzle produces a space 7.

To provide a connection between the spaces in the breathing bag 3 and the canister 1, a plurality of openings 8 for the stream of inhaled or exhaled air to travel through is provided in the wall of the second canister 1 at a suitable distance from one another. Because the connecting nozzles on the canister 1 on the one hand and the openings on the other hand are arranged in this way, the breathing bag need have only one connection opening 9, which is advantageous.

The breathing hose 5 is secured to the outer face of the connecting nozzle 4 by means of a clamping ring 15 while a connector 12 associated with the chemical canister 6 can be inserted against its inner face in such a way as to be held captive. The connecting nozzle 4 thus performs two connecting functions. Connector 12 is stepped at right angles towards the end and terminates parallel to its vertical wall. Inserted into this angle is a sealing ring 16 to seal off the space between the chemical canister 6 and the canister 1 from the breathing hose 5 connected to connecting nozzle 4.

The breathing bag 3 is secured to the connecting nozzle 2 by a clamping ring 15'.

In the breathing bag, opposite the connection opening 9, is provided a second connection opening 10 which is connected to the heat exchanger 11 by means of a clamping ring 15".

WHAT WE CLAIM IS:- 1. Protective breathing apparatus of the kind described, wherein a first connecting nozzle is arranged at the top of the second canister, said connecting nozzle acting as a connector between the breathing bag and the second canister, a second connecting nozzle, having an opening therethrough, being arranged inside and concentric with the first connecting nozzle to act as a connector for the breathing hose and the chemical canister, a space being formed between the first connecting nozzle and the second connecting nozzle and wherein a plurality of openings is provided in the part of the wall of the second canister between the first and second connecting nozzles at a suitable distance from one another.

2. Apparatus as claimed in claim 1, wherein the breathing bag has a connection opening for connection to the first connecting nozzle of the second canister, while a second connection opening is provided in the breathing bag opposite the first connection opening, for connection to the heat exchanger.

3. Apparatus as claimed in claim 1, wherein the second connecting nozzle of the second canister is so arranged that the breathing hose can be connected to its outer face and so that a connector on the chemical canister can be inserted against its inner face in such a way as to be held captive.

4. Protective breathing apparatus, substantially as hereinbefore described with reference to the accompanying drawing.

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

Claims (4)

**WARNING** start of CLMS field may overlap end of DESC **. part is connected to a heat exchanger 11 and whose lower part is connected to the canister 1 and enclosing a breathing hose 5 whose lower end is connected to the canister 6, and a breathing hose extension 13 having a mouth piece 14, which is similarly connected to the heat exchanger 11 via a socket as shown. To enable the breathing bag 3 and the breathing hose 5 to be connected to the canister 1, tubular connecting nozzles 2 and 4 are formed at the top of the canister 1, nozzle 4 being arranged inside and concentric with nozzle 2. This arrangement of the connecting nozzle produces a space 7. To provide a connection between the spaces in the breathing bag 3 and the canister 1, a plurality of openings 8 for the stream of inhaled or exhaled air to travel through is provided in the wall of the second canister 1 at a suitable distance from one another. Because the connecting nozzles on the canister 1 on the one hand and the openings on the other hand are arranged in this way, the breathing bag need have only one connection opening 9, which is advantageous. The breathing hose 5 is secured to the outer face of the connecting nozzle 4 by means of a clamping ring 15 while a connector 12 associated with the chemical canister 6 can be inserted against its inner face in such a way as to be held captive. The connecting nozzle 4 thus performs two connecting functions. Connector 12 is stepped at right angles towards the end and terminates parallel to its vertical wall. Inserted into this angle is a sealing ring 16 to seal off the space between the chemical canister 6 and the canister 1 from the breathing hose 5 connected to connecting nozzle 4. The breathing bag 3 is secured to the connecting nozzle 2 by a clamping ring 15'. In the breathing bag, opposite the connection opening 9, is provided a second connection opening 10 which is connected to the heat exchanger 11 by means of a clamping ring 15". WHAT WE CLAIM IS:-

1. Protective breathing apparatus of the kind described, wherein a first connecting nozzle is arranged at the top of the second canister, said connecting nozzle acting as a connector between the breathing bag and the second canister, a second connecting nozzle, having an opening therethrough, being arranged inside and concentric with the first connecting nozzle to act as a connector for the breathing hose and the chemical canister, a space being formed between the first connecting nozzle and the second connecting nozzle and wherein a plurality of openings is provided in the part of the wall of the second canister between the first and second connecting nozzles at a suitable distance from one another.

2. Apparatus as claimed in claim 1, wherein the breathing bag has a connection opening for connection to the first connecting nozzle of the second canister, while a second connection opening is provided in the breathing bag opposite the first connection opening, for connection to the heat exchanger.

3. Apparatus as claimed in claim 1, wherein the second connecting nozzle of the second canister is so arranged that the breathing hose can be connected to its outer face and so that a connector on the chemical canister can be inserted against its inner face in such a way as to be held captive.

4. Protective breathing apparatus, substantially as hereinbefore described with reference to the accompanying drawing.