Breating apparatus with closed circuit

The present invention relates to a closed circuit breathing apparatus.

Closing devices with closed circuit and electrical control allow to maintain the oxygen level of the respiratory air conducted in the circuit, depending on the ambient pressure, for example when used as a diving breathing apparatus, and with the required normal fraction of about 21%. However, it must be ensured that the device can continue to function even in the event of accidental interruption of the respiratory gas control, or that it can in any case return to its starting base.

In a known closed-circuit breathing apparatus that can be worn on the back, the partial oxygen pressure in the circuit is maintained at the desired value by an electronic device.

In a first embodiment of the apparatus, the circuit comprises a breathing apparatus connection with a mouthpiece and directional outlets for two breathing bags, one on the inhalation and one on the exhalation side, which are connected to each other via a carbon dioxide absorption cartridge. The necessary oxygen is supplied from the cylinder via a parallel connection of the hand-adjustable valve and the maagneic valve on the inlet side of the absorption cartridge, which is closed when it is at rest. An electrochemical oxygen sensor is provided on the outlet side of the absorption cartridge, which controls the partial oxygen pressure in the circuit to an adjustable setpoint by means of an electronic galvanic device and the associated magnitude. The measured oxygen partial pressure value is indicated on an indicator device arranged on the wristband. The wearable venn-il is configured to provide the oxygen supply necessary for the survivor. The standard delivery is then ensured by means of diagnosis venous.

In a second embodiment, the oxygen uptake is effected via a series arrangement of the solid venous and mBaltic valve controlled by a control device, open in a coded state in the direction of the breathing bag connected on the inhalation side. In the event of a fault, for example, a failure of the valve, if the sensor signal does not reach the limit value, an optical and / or acoustic warning signal is given. The bypass of the magnetic venous is then manually engaged and oxygen is continuously fed through the solid oennil.

It is disadvantageous that, in the event of a failure of the apparatus in the first embodiment, an emergency oxygen supply is maintained, but this is not sufficient for a normal need, which may also be necessary for the user to return. If the fault is not resolved by constant observation of the indicating device, it may nevertheless lead to a dangerous reduction in the risk of frost. of oxygen in the circuit. In the second embodiment, manual switching is necessary in the event of a failure. This implies early detection of the failure by observing the indicating device or the alarm signal and then retaining the user's ability to do so - U.S. Patent No. 32,525,458.

In the known breathing apparatus with circuit, in particular for underwater work, a one-way controlled gas is supplied. They were flapped from the mixing chamber through the mouthpiece, possibly also in mm, to the user and from there through the blower bag and the carbon dioxide receiver back to the mixing chamber. The safety outside on the breathing bag puts any overpressure into the eye. The cylinder is mixed with inert gas and oxygen and is connected to the circuit via a pressure regulating valve, a pressure equalizing valve, and a pressure regulating valve. The oxygen is connected via a pressure regulating valve and a manually operable hook is discharged through the chamber. In parallel to the pushbutton of the valve, there are mutually disconnected oennil and sagneic oennil disconnectors which are actuated by an electric current circuit. The current circuit is connected to two sensors arranged. in one chamber, one indicating total pressure and the other partial oxygen pressure. The circuit connection is further controlled by controlling the oxygen flow so that either a constant partial pressure of oxygen or a predetermined percentage of oxygen is maintained in the circuit. If the oxygen partial pressure exceeds the limit, harmful to health, the circuit of the current circuit closes the megnotic isolator out! until the oxygen partial pressure drops again and indicates that it is exceeded by the warning alarm. In addition, on the warning lamps arranged inside the mask, the oxygen content is indicated here in the desired range, above or below it. To increase safety, it is suggested to use a second identical wiring in case a failure occurs in the first. As an additional control device, a third sensor, operating without the use of external energy, is arranged in the measuring chamber, which measures the partial pressure of oxygen without connection to the current circuit and indicates it on an independent metering device. In the event of a malfunction, the user may initiate the emergency power supply manually by means of the two push-button valves from the oxygen cylinder or by inert gas and oxygen.

The disadvantage is that despite the high cost of the electronics and mechanical parts of the device, the user is forced to detect the fault by observing the data and signals and then while monitoring the values ​​indicated by the device, continuous manual control that limits it for emergency power supply - NSR published application No. 26 08 546.

These drawbacks of the known closed-circuit breathing apparatuses are overcome by the breathing apparatus according to the invention, the subtype of which is based on the invention. wherein the oxygen supply line is connected via a pressure reducer to a transfer valve which is connected via a second control device to a second oxygen sensor in a breathing bag, the transfer valve being further in the first flow path via an electromagnetic valve connected to the first control device with the first oxygen sensor in the breathing bag, connected by a duct to the breathing bag, and in the second flow path, by a transfer duct, which is directly connected to the respiratory bag by a branch with a dispenser, connected to a pulmonary automat.

It is advantageous if the control devices are provided with separate power sources for the supply of energy and are connected to the operating convenience indicators.

The oxygen sensors are preferably electrochemical and the second differential element control device is connected to the first control device by a connecting line.

A new and higher effect of the invention is that the breathing apparatus is automatically switched to the additional supply of respiratory air in the event of a malfunctioning operation by means of a maagee valve.

With the loss of control with the maageeic venOil, it stops the oxygen supply to the breathing circuit. The user of the device is due to a self-switching solution and other supply path of the breathing apparatus. further supplied with respirable respiratory gas.

The solution consists in a switching valve controlled by a second oxygen sensor, which, after switching to a new path, provides oxygen to the breathing apparatus circuit. Proven devices such as the basic metering nozzle and pulmonary dispenser are used to compensate for peak demand. The oxygen demand is maintained as low as possible even after a normal power failure. This allows the user of the device not only to return but also to execute the intended task.

An exemplary embodiment of the invention is shown in the drawing and described below. In the drawing, the breathing apparatus is shown schematically.

the SCBA operates on a circuit basis. Coortruction is shown by the excretion * es. The circuit in the flow direction in the inhalation section consists of a breathing bag 2, an inhalation valve 1, an inhalation hose 4 and a breathing apparatus connection 2. The inhaled air is then passed through the exhalation hose 6, the exhalation outlet 1 and the absorption cartridge 8 in which the oxygen is bound. it returns to the breathing bag 2 of the breathing apparatus. The oxygen consumed is replenished from the reservoir. For this purpose, an oxygen cylinder 2 is provided, provided with a shut-off valve 10. A shut-off valve 11 is connected to the shut-off valve 11. The rear pressure connection is connected to the electrically controlled transfer valve 17 via the inlet duct 13. pressure reducing valve Ц.

The first flow path leads through the solenoid valve 18 through a line 24 to the breathing apparatus. The solenoid valve 18 is part of the first regulating device 22 and is controlled by the first regulating device 22 according to the first oxygen sensor 20 in the breathing bag 2 of the breathing apparatus. .

A second flow path leads from the switch valve 17 via line 25, on the one hand through a branch, 26 with a dispenser 19, to the breathing bag 2 of the breathing apparatus 1 and, on the other hand, via the transfer line 14 to the pulmonary device 15.

The switching valve 17 is controlled by the second regulating device 23 according to the data of the second oxygen sensor 21 in the breathing bag 2 of the breathing apparatus.

The two regulating devices 22, 23 each have one power source 27, 28 for supplying power and are connected to the operating standby or operation indicators.

During normal operation, the breathing apparatus 8 and thus the user of the apparatus are supplied with the necessary oxygen by the first current path. By consuming oxygen through the first oxygen sensor 20, the consumed oxygen is fed to the breathing circuit via the electromagnetic outlet 18. In the event of a failure during normal operation and hence the electromagnetic venous 18, the oxygen content of the breathing circuit is reduced. It could also happen that, for example, the oxygen content of the first oxygen sensor 80 is too high or the electromagnetic venous 18 fails. In both cases, once the oxygen concentration limits are reached, the transfer valve 17 is switched to the second flow path via the second oxygen sensor 21 and the second regulating device 33. Thus, the oxygen then flows in a known manner at a basic rate through the dispenser 19 into the breathing bag 2 of the breathing apparatus 4, and to compensate for the peak demand controlled by the automated furnace 15 via the switch line 14 to the breathing apparatus user.