Gas flow controller and a valve pin for a gas flow controller

Patent metadata

Field	Value
Publication number	US-2020353202-A1
Application number	US-201916961095-A
Country	US
Kind code	A1
Filing date	Jan 10, 2019
Priority date	Jan 10, 2018
Publication date	Nov 12, 2020
Grant date	—

Abstract

The invention relates to gas flow controllers, for example to gas blender units such as an air/oxygen blender (2) for healthcare use, and to a valve (8) and valve pin (20,120) suitable for use in such a flow controller (20). In particular, a medical gas blender (2) is provided that avoids the need for pre-regulation by incorporating one or more flow control valves (8) having a high turndown ratio. Valves suitable for use in such a blender, or otherflow controller (2), are also disclosed.

First claim

1 . A medical gas blender comprising:
a first inlet for connection to a first gas supply, a second inlet for connection to a second gas supply; a mixing chamber; a first flow regulation valve located between the first inlet and the mixing chamber for controlling the flow of a first gas to the mixing chamber; a second flow regulation valve located between the second inlet and the mixing chamber for controlling the flow of a second gas to the mixing chamber; an outlet; and control hardware for controlling the operation of at least one of the first and second flow regulation valves; wherein the first and second flow regulations valves have a turndown ratio in excess of 1000:1.

2 . A medical gas blender according to claim 1 , wherein the control hardware is configured to perform a measuring step, in which a gas flow is measured, and a comparison step, in which the measured gas flow is compared with a target flow.

3 . A medical gas blender according to claim 2 , wherein the control hardware is configured to select a gas flow prior to the measuring step.

4 . A medical gas blender according to claim 2 or 3 , wherein the control hardware is configured to additionally measure oxygen content and calculate individual gas flows as part of the measuring step.

5 . A medical gas blender according to claim 4 , wherein at least one of the first and second flow regulation valves comprises a valve member driven by a motor, and wherein the control hardware is configured to move the motor a number of steps based on the outcome of the comparison step.

6 . A medical gas blender according to claim 5 , wherein the valve member comprises a valve pin.

7 . A medical gas blender according to claim 6 , wherein the valve pin comprises an elongate body with a first end and a second, free, end remote from the first end, an outer sealing surface and a tapered part tapering towards the second end of the body, wherein a sealing position is provided towards the first end of the valve body, and wherein the valve pin is shaped to increase the flow area of the valve close to the sealing position.

8 . A medical gas blender according to claim 7 , wherein a recess is provided in the outer sealing surface of the body close to the sealing position.

9 . A medical gas blender according to claim 8 , wherein the recess comprises an elongate channel or slit, the length of the slit being aligned with the length of the elongate body.

10 . A medical gas blender according to claim 9 , wherein the depth of the elongate slit varies along the length of the slit.

11 . A medical gas blender according to claim 10 , wherein the outer sealing surface has a substantially constant cross-section, and the tapered part of the body is provided by the variation in depth of the elongate slit.

12 . A medical gas blender according to claim 11 , wherein the elongate slit is flared towards the free end of the body.

13 . A medical gas blender according to claim 12 , wherein the slit provides an open end section at the free end of the body.

14 . A medical gas blender according to any of claims 8 to 10 , wherein the tapered part of the body is provided by a tapering of the outer sealing surface at the second end such that the body of the valve pin has a first portion of substantially constant cross-section and a second separate portion tapered towards the free end, the sealing position being provided on the first portion.

15 . A medical gas blender according to any of claims 8 to 14 , wherein first and second elongate slits are provided.

16 . A medical gas blender according to claim 15 , wherein the length of the first elongate slit is greater than the length of the second elongate slit.

17 . A medical gas blender according to claims 1 to 5 , wherein the valve member comprises rotating discs.

18 . A gas flow controller comprising an inlet for connection to a gas supply, an outlet, and a flow regulation valve between the inlet and the outlet for controlling flow of gas from a gas supply to the outlet, wherein the flow regulation valve comprises a valve pin and a sealing element surrounding the valve pin to provide a seal between the sealing element and the valve pin at a sealing position on the valve pin, and wherein relative movement of the valve pin and the sealing element away from the sealing position provides a variable flow area between the sealing element and the valve pin to adjust the gas flow at the outlet through a range of flow rates or pressures.

19 . A gas flow controller according to claim 18 , wherein the valve pin is shaped to increase the flow area of the valve close to the sealing position.

20 . A gas flow controller according to claim 19 , wherein an outer surface of the valve pin comprises a recess to increase the flow area close to the sealing position.

21 . A gas flow controller according to claim 20 , wherein the recess comprises an elongate slit.

22 . A gas flow controller according to claim 21 , wherein the elongate slit is aligned with a plane passing through a central axis of the valve pin.

23 . A gas flow controller according to claim 21 or 22 , wherein the depth of the elongate slit varies along the length of the slit.

24 . A gas flow controller according to claim any of claims 21 to 23 , wherein the slit is provided between a free end of the valve pin and the sealing position.

25 . A gas flow controller according to claim 24 , wherein the depth of the elongate slit reduces from the free end of the valve pin towards the sealing position.

26 . A gas flow controller according to any of claims 21 to 25 , wherein the width of the elongate slit is constant along the length of the slit.

27 . A gas flow controller according to any of claims 18 to 26 , further comprising a linear stepper motor connected to the valve pin for moving the valve pin relative to the sealing element.

28 . A gas flow controller according to any of claims 18 to 27 , wherein the valve pin has a taper towards a free end of the pin.

29 . A gas flow controller according to any of claims 18 to 28 , wherein the valve pin has a first un-tapered section and a second tapered section towards a free end of the pin.

30 . A gas flow controller according to claim 29 , wherein the sealing position is on the first section of the valve pin.

31 . A gas flow controller according to claim 29 or 30 , wherein the first section of the valve pin is shaped to increase the flow area of the valve close to the sealing position.

32 . A medical gas flow controller according to any of claims 18 to 31 .

33 . A medical gas blender comprising a medical gas flow controller according to claim 32 , and further comprising a mixing chamber, wherein the flow regulation valve is located between an inlet and the mixing chamber for controlling the flow of gas to the mixing chamber.

34 . A medical gas blender according to claim 33 , wherein two flow regulation valves are provided, each flow regulation valve being located between an inlet and the mixing chamber, and each flow regulation valve comprising a valve pin and a sealing element surrounding the valve pin to provide a seal between the sealing element and the valve pin at a sealing position on the valve pin, and wherein relative move

Assignees

• Intersurgical Ag

Inventors

• Miller Andrew
• Browne Mark
• Dixon Philip

Classifications

• A61M16/204

  used for inhalation control · CPC title

• A61M16/203

  Proportional · CPC title

• A61M16/20 Primary

  Valves specially adapted to medical respiratory devices · CPC title

• F16K31/04

  using a motor · CPC title

• A61M2016/0039

  in the inspiratory circuit · CPC title