Gas mixing apparatus particularly for respirators and medical devices

• US 3,896,837 A
• Filed: 10/03/1973
• Issued: 07/29/1975
• Est. Priority Date: 10/13/1972
• Status: Expired due to Term

• Current Assignee: Holmer Rohling
• Original Assignee: Holmer Rohling
• Inventors: Rohling, Holmer
• Primary Examiner(s): Nilson, Robert G.
• Application Number:
  US05/402,886
• Time in Patent Office: 664 Days
• Field of Search: 137/88,110,113,89 128/210
• US Class Current: 137/110
• CPC Class Codes: A61M 16/1015 using a gas flush valve, e.g. oxygen flush valve
• CPC Class Codes: A61M 16/12 by mixing different gases
• CPC Class Codes: B01F 23/191 characterised by the construction of the controlling means
• CPC Class Codes: Y10T 137/2562 Dividing and recombining
• CPC Class Codes: Y10T 137/2569 Control by depletion of source

Abstract

A gas mixing apparatus for gases under pressure particularly for respirators and medical devices which has a plurality of compressed gas supply lines which are connected to a mixing device for delivery into a mixed gas delivery line includes at least one by pass connected from at least one compressed gas supply line to the delivery line. The by pass line includes an automatically pressure operated shut off valve which is responsive to a drop off in pressure to feed gas through the by pass line to the delivery line. The shut off valve includes a settable spring biased diaphragm which carries a movable valve member which is urged against the valve seat at pressure conditions which are set for the normal operation of the device. The by pass line is open to deliver gas from the compressed air lines to the delivery line whenever the delivery line pressure drops off. A warning signal may also be arranged in the connection and in some instances a compressed gas connection to the by pass line provides means for feeding gas from a separate compressed gas supply in the event delivery pressure drops off.

Claims

1. A gas mixing apparatus for gases under pressure, particularly for respirators and medical devices, comprising a gas mixer device, a plurality of compressed gas supply lines connected to said gas mixer device, at least one mixed gas delivery line extending out of said gas mixer device for the discharge of a mixture of gases from said compresSed gas supply lines from said gas mixer device, and at least one by pass line connected from a compressed gas supply line to said delivery line and having an automatic pressure operated shutoff valve therein responsive to a drop in pressure in said delivery line to feed gas through said by pass line to said delivery line whenever the pressure therein drops below a predetermined value, said at least one by pass line comprising a by pass line connected to each of said supply lines each having an automatically operable pressure operated shutoff valve.

2. A gas mixing apparatus according to claim 1, wherein said automatically operable pressure operated shutoff valve includes means for adjusting said valve to vary the pressure in which it opens.

3. Gas mixing apparatus, according to claim 1, wherein the opening pressures of said shutoff valves are set distinctly.

4. Gas mixing apparatus, according to claim 1, including a warning signal arrangement which indicates when the pressure drops below a definite pressure, is connected to said mixed gas delivery line.

5. Gas mixing apparatus according to claim 4, characterized in that the warning signal arrangement is an acoustic warning signal arrangement.

6. Gas mixing apparatus according to claim 5, including a signal conduit leading to the warning signal arrangement 10 having a shutoff signal valve which opens automatically when the pressure in the mixed gas delivery line drops below a predetermined pressure.

7. A gas mixing apparatus for gases under pressure, particularly for respirators and medical devices, comprising a gas mixer device, a plurality of compressed gas supply lines connected to said gas mixer device, at least one mixed gas delivery line extending out of said gas mixer device for the discharge of a mixture of gases from said compressed gas supply lines from said gas mixer device, and at least one by pass line connected from a compressed gas supply line to said delivery line and having an automatic pressure operated shutoff valve therein responsive to a drop in pressure in said delivery line to feed gas through said by pass line to said delivery line whenever the pressure therein drops below a predetermined value, said plurality of compressed air gas supply lines comprising two sets of supply lines said at least one by pass line including a by pass line connected to each separate supply line, each by pass line having a pressure operated shutoff valve including a valve housing having aa diaphragm extending thereacross, adjustable spring means biasing one side of said diaphragm, a movable valve member carried by the other side of said diaphragm, said other side of said diaphragm being connected to said by pass line, said by pass line having a valve seat which is closed by said movable valve member, said diaphragm being movable with said movable valve member upon the reduction of pressure in said delivery line to move said movable valve member off said valve seat and to communicate gas from said gas supply line through said by pass line to said mixed gas delivery line.

8. A mixing apparatus according to claim 7, including a warning signal connected in said by pass line having a movable diaphragm operated valve member which is openable by a reduction of pressure in said delivery line to actuate said warning signal.