Pneumatic module and process for supplying a consumer with a pressure surge-free stream of medical gases or medical air

A ventilation system for supplying a patient with a breathing gas, the ventilation system comprising:

• a ventilator comprising a compressor for providing an air and/or gas stream at a ventilator outlet;
• a hose system configured to feed the air and/or gas stream at least partially to a patient;
• and
• a pneumatic module comprising:
• a module inlet connected at least indirectly to the ventilator outlet:
• a module outlet connected to a hose system inlet of the hose system;
• a main flow duct from the module inlet to the module outlet;
• a flow valve connected to the main flow duct and configured to set a volume flow of a breathing gas stream flowing downstream of the flow valve;
• a pressure relief valve pneumatically connected to the main flow duct downstream of the flow valve and configured to vent the main flow duct upon a pressure in the main flow duct exceeding a permissible maximum pressure, the pressure relief valve having a control port;
• a control duct connected to the control port and branching off from the main flow duct at a branch upstream of the flow valve;
• a pressure control unit connected to the control duct and configured to set a flow value, indicative of a control flow, which flows through the control duct and which acts on the control port, for setting the permissible maximum pressure;
• and
• a compensating element configured to provide a compensating volume for the control duct, wherein the control port is connected to the compensating element, the compensating element comprising an elastically deformable element at least indirectly functionally connected with the control port, the elastically deformable element comprising an elastic expansion bellows, the compensating element being configured to receive fluid from the control port, wherein the control duct comprises a control duct outlet downstream of the pressure control unit, via which the control flow can be released into a surrounding area under an atmospheric pressure prevailing in the surrounding area, the compensating element being connected to the control duct at a position located between the control duct outlet and the control port, the compensating element, the control port and the outlet being located on one side of the pressure relief valve.

A process for supplying a consumer with a pressure surge-free stream of a medical gas and/or medical air, the process comprising the steps of:

• providing a stream of a medical gas and/or medical air into a main flow duct at an inlet of the main flow duct;
• sending a first part of the stream of a medical gas and/or medical air in the main flow duct to a flow valve, via which a volume flow of a breathing gas stream flowing downstream of the flow valve is set;
• venting the main flow duct by means of a pressure relief valve upon a permissible maximum pressure being exceeded;
• and
• branching off a second part of the provided stream of a medical gas and/or medical air into a control duct upstream of the flow valve and sending the second part of the provided stream of a medical gas and/or medical air in the control duct to a pressure control unit configured to set a flow value indicative of a control flow, which flows through the control duct and acts on a control port of the pressure relief valve for setting the permissible maximum pressure
• compensating or absorbing pressure surges and air and/or gas volumes displaced thereby, which occur at the control port of the pressure relief valve, in a compensating volume, which is generated by an at least partially elastic deformation of a compensating element, which compensating element is operatively connected to the control port, the compensating element comprising an elastically deformable element at least indirectly functionally connected with the control port, the elastically deformable element comprising an elastic expansion bellows, the compensating element being configured to receive fluid from the control port, wherein the control flow is released from the control duct via an outlet into a surrounding area under an atmospheric pressure prevailing in the surrounding area, the compensating element being connected to the control duct at a position located between the outlet and the control port, the control port, the compensating element and the outlet being located on one side of the pressure relief valve.