Respiration system
View Patent ↗A respiration system feeds an anesthetic gas having, a density ρ gas , with a Y-piece for connection to a patient, with a respiration circuit having an inspiration branch and an expiration branch, which extend away from the Y-piece. A first supply line from a branch in the expiration branch leads to an anesthetic gas discharge valve and a second supply line from the branch leads to a reservoir. A too high pressure, opposing expiration, cannot build up in the expiration branch and losses of anesthetic gas are kept to a minimum. A prestressing device exerts a prestressing force onto the valve body of the anesthetic gas discharge valve against the effect of gravity. The mass m valve and the prestressing force determine a threshold pressure in the anesthetic gas discharge line that results in an opening of the anesthetic gas discharge valve.
1. A respiration system for feeding an anesthetic gas having a density ρ gas , the system comprising:
a Y-piece for connection to a patient;
a respiration circuit with an inspiration branch and an expiration branch, which extend away from the Y-piece;
a branching in the expiration branch;
an anesthetic gas discharge valve;
a first supply line connected from the branching and leading to the anesthetic gas discharge valve;
a reservoir;
a second supply line connected from the branching and leading to the reservoir, said second supply line having a cross-sectional area A supply line 2 and a length l supply line 2 , wherein:
the anesthetic gas discharge valve comprises a valve body having a mass which is pressed, by means of the effect of gravity, towards the first supply line against a circular-ring-shaped valve seat having a diameter; and
the anesthetic gas discharge valve includes a prestressing means for exerting a prestressing force onto the valve body against the effect of gravity, so that the mass and the prestressing force determine a threshold pressure about which the pressure in the first supply line has to lie at least above that on the side of the anesthetic gas discharge valve facing away from the first supply line to open the anesthetic gas discharge valve.
2. A respiration system in accordance with claim 1 , wherein the mass m valve of the valve body is selected such that
m
valve
>
2
·
π
2
·
l
supplyline
2
2
·
V
.
intersection
·
ρ
gas
2
·
d
valve
3
·
(
Δ
P
-
Δ
P
threshold
)
8
·
A
supplyline
2
2
·
Δ
P
2
·
ρ
gas
Δ
P
applies, whereby {dot over (V)} intersection ≧10 L/min, ΔP=5 mbar and ΔP threshold =1.1 mbar and a density ρ gas of a fluid in the respiration system is between 1.12 kg/m 3 and 2.19 kg/m 3 .
3. A respiration system in accordance with claim 2 , whereby {dot over (V)} intersection ≧60 L/min applies.
4. A respiration system in accordance with claim 1 , wherein the reservoir is embodied as a flexible manual respiration bag with a variable volume.
5. A respiration system in accordance with claim 4 , whereby the prestressing means comprises a coil spring lying against the valve body with a first end, which presses on the valve body against the effect of gravity and which is arranged on a side of the valve body pointing in the direction of the gravity.
6. A respiration system in accordance with claim 5 , further comprising:
an adjusting screw mounted axially adjustably in the valve housing, wherein a second end of the coil spring is supported against the adjusting screw.
7. A respiration system in accordance with claim 1 , wherein:
the anesthetic gas discharge valve has a valve housing, in which the valve seat is provided;
the valve seat extends in a seat plane running at right angles to the direction of gravity and points in a direction opposite the direction of gravity; and
the valve body is arranged such that it lies on valve seat under the effect of gravity.
8. A respiration system for feeding an anesthetic gas having a density ρ gas , the system comprising:
a Y-piece for connection to a patient;
a respiration circuit with an inspiration branch and an expiration branch, which extend away from the Y-piece;
a branching in the expiration branch;
a reservoir;
a reservoir line connected from the branching and leading to the reservoir, said second supply line having a cross-sectional area A supply line 2 and a length l supply line 2 ;
an anesthetic gas discharge line connected from the branching;
an anesthetic gas discharge valve connected to the anesthetic gas discharge line, the anesthetic gas discharge valve comprises a circular-ring-shaped valve seat having a dimension, a valve body having a mass which is pressed, by means of the effect of gravity toward the circular-ring-shaped valve seat, the valve body being acted on by fluid pressure in the anesthetic gas discharge line in a direction against the effect of gravity and being acted on by atmospheric pressure in a direction of the effect of gravity and a prestressing means for exerting a prestressing force onto the valve body against the effect of gravity, so that the mass and the prestressing force determine a threshold pressure of the fluid pressure in the anesthetic gas discharge line that results in an opening of the anesthetic gas discharge valve.
9. A respiration system in accordance with claim 8 , wherein the mass m valve of the valve body is selected such that
m
valve
>
2
·
π
2
·
l
supplyline
2
2
·
V
.
intersection
·
ρ
gas
2
·
d
valve
3
·
(
Δ
P
-
Δ
P
threshold
)
8
·
A
supplyline
2
2
·
Δ
P
2
·
ρ
gas
Δ
P
wherein A supply line 2 is a cross-sectional area of said second supply line and l supply line 2 is a length of said second supply line and {dot over (V)} intersection ≧10 L/min, ΔP=5 mbar and ΔP threshold =1.1 mbar and a density ρ gas of a fluid in the respiration system is between 1.12 kg/m 3 and 2.19 kg/m 3 .
10. A respiration system in accordance with claim 9 , whereby {dot over (V)} intersection ≧60 L/min.
11. A respiration system in accordance with claim 8 , wherein the reservoir is embodied as a flexible manual respiration bag with a variable volume.
12. A respiration system in accordance with claim 8 , wherein:
the anesthetic gas discharge valve has a valve housing, in which the valve seat is provided;
the valve seat extends in a seat plane running at right angles to the direction of gravity and points in a direction opposite the direction of gravity; and
the valve body is arranged such that it lies on valve seat under the effect of gravity.
13. A respiration system in accordance with claim 12 , whereby said prestressing means comprises a coil spring lying against the valve body with a first end, which presses on the valve body against the effect of gravity and which is arranged on a side of the valve body pointing in the direction of the gravity.
14. A respiration system in accordance with claim 13 , further comprising:
an adjusting screw mounted axially adjustably in the valve housing, wherein a second end of the coil spring is supported against the adjusting screw.
15. A respiration system for feeding an anesthetic gas having a density ρ gas , the system comprising:
a Y-piece for connection to a patient;
a respiration circuit with an inspiration branch and an expiration branch, which extend away from the Y-piece;
a branching in the expiration branch;
a reservoir;
a reservoir line connected from the branching and leading to the reservoir, said second supply line having a cross-sectional area A supply line 2 and a length l supply line 2 ;
an anesthetic gas discharge line connected from the branching;
an anesthetic gas discharge valve connected to the anesthetic gas discharge line, said anesthetic gas discharge valve comprising a circular-ring-shaped valve seat having a dimension, a valve body having a mass which is pressed, by means of the effect of gravity toward the circular-ring-shaped valve seat, the valve body being acted on by fluid pressure in the anesthetic gas discharge line in a direction against the effect of gravity and being acted on by atmospheric pressure in a direction of the effect of gravity and a prestressing means for exerting a prestressing force onto the valve body against the effect of gravity, so that the mass and the prestressing force determine a threshold pressure of the fluid pressure in the anesthetic gas discharge line that results in an opening of the anesthetic gas discharge valve, said valve body having a valve body surface facing in the direction of the effect of gravity, said prestressing means engaging said valve body surface.
16. A respiration system in accordance with claim 15 , wherein said threshold pressure is exclusively defined by said mass of said valve body and said prestressing force.
17. A respiration system in accordance with claim 15 , wherein the mass m valve of the valve body is selected such that
m
valve
>
2
·
π
2
·
l
supplyline
2
2
·
V
.
intersection
·
ρ
gas
2
·
d
valve
3
·
(
Δ
P
-
Δ
P
threshold
)
8
·
A
supplyline
2
2
·
Δ
P
2
·
ρ
gas
Δ
P
applies, whereby {dot over (V)} intersection ≧10 L/min, ΔP=5 mbar and ΔP threshold =1.1 mbar and a density ρ gas of a fluid in the respiration system is between 1.12 kg/m 3 and 2.19 kg/m 3 , d corresponding to a diameter of the valve body, wherein the diameter of the valve body, the cross-sectional area A supply line 2 and the length l supply line 2 are greater than zero.
18. A respiration system in accordance with claim 17 , whereby {dot over (V)} intersection ≧60 L/min applies.
19. A respiration system in accordance with claim 15 , wherein the reservoir is embodied as a flexible manual respiration bag with a variable volume.
20. A respiration system in accordance with claim 15 , wherein:
the anesthetic gas discharge valve has a valve housing, in which the valve seat is provided;
the valve seat extends in a seat plane running at right angles to the direction of gravity and points in a direction opposite the direction of gravity; and
the valve body is arranged such that it lies on valve seat under the effect of gravity.