Pressure control device for maintaining a constant predetermined pressure in a container

• US 7,467,733 B2
• Filed: 09/09/2003
• Issued: 12/23/2008
• Est. Priority Date: 05/29/1998
• Status: Expired due to Fees

• Current Assignee: Ips Patent S.A.
• Original Assignee: Packaging Technology Holding S.A.
• Inventors: van't Hoff, Jaap Herman
• Primary Examiner(s): RIVELL, JOHN A
• Application Number:
  US10/657,250
• Publication Number:
  US 20040045986A1
• Time in Patent Office: 1,932 Days
• Field of Search: 137/505.41, 137/906, 137/571, 222/389, 222/399
• US Class Current: 222/389
• CPC Class Codes: B65D 83/64 by piston
• CPC Class Codes: B65D 83/663 at least a portion of the propellant being separated from the product and incrementally released by means of a pressure regulator
• CPC Class Codes: F16K 15/063 the valve being loaded by a spring
• CPC Class Codes: Y10T 137/7905 Plural biasing means
• CPC Class Codes: Y10T 137/7929 Spring coaxial with valve

Abstract

A pressure control device for maintaining a constant predetermined pressure in a container which is arranged for dispensing a fluid contained in the container from the container at said pressure, the pressure control device comprising a first chamber and a second chamber, as well as at least one closing member movable relative to the second chamber for releasing and closing a fluid connection between the first chamber and the container depending on the position of the closing member relative to the second chamber. The first chamber is filled with a gas which, in use, has a higher pressure than the pressure in the container. The second chamber is located outside the first chamber.

Claims

1. A pressure control device for maintaining a constant predetermined excess pressure in a fluid dispensing container, which device comprises a first chamber, a fluid connection between the first chamber and the container, wherein the fluid connection comprises a first opening in the sidewall of the first chamber, a valve with a closing member for releasing and closing said fluid connection and a resilient pressure element exerting said predetermined excess pressure onto the closing member in a closing direction, the resilient pressure element comprising a second chamber being filled with a gas at the predetermined excess pressure and relative to which the closing member is movable, wherein the second chamber is provided with a second opening, the closing member extending from the first chamber through the first and second opening to the second chamber, a first subsurface of the closing member being situated in the first chamber and a second subsurface of the closing member being situated in the second chamber, the first chamber being filled with a gas at a pressure higher than said predetermined excess pressure, the size of the first subsurface is substantially smaller than the size of the second subsurface, such that the gas pressure in the first chamber results in that the force on the first subsurface is smaller than the force on the second subsurface resulting from the predetermined excess pressure, while in use the first opening is released if the fluid pressure in the container drops below the predetermined excess pressure, so that gas flows from the first chamber to the container and the pressure in the container increases until the first opening is closed again by the closing member as a result of the increased pressure in the container, wherein the second chamber consists of a cylinder which is closed at a first end and of which a second end constitutes said second opening, and the closing member comprises a plunger movable in axial direction of the cylinder so as to change the volume of the second chamber, and wherein the closing member is movable in a reciprocated manner between a first extreme position and a second extreme position, whereby the fluid connection is closed, which first and second extreme positions are defined by an axial extend of a circumferential recess in the valve and the release position of the closing member is defined between the first and second closing positions and wherein the second subsurface forms a cavity in the plunger of the closing member;

and

wherein the device is arranged to be received in a cylindrical container, the first chamber being designed as a plunger which is arranged to be received, in use, in the container so as to be movable in an axial direction of the container, the first chamber dividing the container into an upper and a lower part, the fluid connection terminating in the lower part of the container, while the upper part of the container is filled with the fluid to be dispensed, and in use, when the pressure in the upper part of the container decreases below the predetermined pressure, the pressure in the lower part of the container will likewise decrease because the first chamber designed as a plunger will move such that the volume of the upper part of the container will decrease whereas the volume of the lower part of the container will increase, whereby also the fluid connection between the first chamber and the lower part of the container is released, so that gas flows from the first chamber to the lower part of the container and the pressure in the lower part of the container as well as the pressure in the upper part of the container will rise again, while the chamber designed as a plunger moves further upwards until the fluid connection is closed again by the closing member as a result of the increased pressure in the lower part of the container.

2. A device according to claim 1, wherein at the first and second extreme positions, a gas seal is formed by contact between a first sealing ring and an outer edge of the closing member.

3. A device according to claim 1, wherein the closing member comprises a stem with the circumferential recess.

4. A device according to claim 1, wherein the plunger is sealed by an outer second sealing ring with respect to the inner wall of the second chamber.

5. A device according to claim 1, wherein the second chamber is located outside the first chamber.

6. A device according to claim 5, wherein the closing member is located substantially outside the first chamber.

7. A device according to claim 1, wherein the volume of the first chamber is substantially greater than the volume of the second chamber.

8. A device according to claim 1, wherein the second chamber extends substantially in the lower part of the container.

9. A container provided with a device according to claim 1.

10. A pressure control device for maintaining a constant predetermined excess pressure in a fluid dispensing container, which device comprises a first chamber, a fluid connection between the first chamber and the container, wherein the fluid connection comprises a first opening in the sidewall of the first chamber, a valve with a closing member for releasing and closing said fluid connection and a resilient pressure element exerting said predetermined excess pressure onto the closing member in a closing direction, the resilient pressure element comprising a second chamber being filled with a gas at the predetermined excess pressure and relative to which the closing member is movable, wherein the second chamber is provided with a second opening, the closing member extending from the first chamber through the first and second opening to the second chamber, a first subsurface of the closing member being situated in the first chamber and a second subsurface of the closing member being situated in the second chamber, the first chamber being filled with a gas at a pressure higher than said predetermined excess pressure, the size of the first subsurface is substantially smaller than the size of the second subsurface, such that the gas pressure in the first chamber results in that the force on the first subsurface is smaller than the force on the second subsurface resulting from the predetermined excess pressure, while in use the first opening is released if the fluid pressure in the container drops below the predetermined excess pressure, so that gas flows from the first chamber to the container and the pressure in the container increases until the first opening is closed again by the closing member as a result of the increased pressure in the container, wherein the second chamber consists of a cylinder which is closed at a first end and of which a second end constitutes said second opening, and the closing member comprises a plunger movable in axial direction of the cylinder so as to change the volume of the second chamber, and wherein the closing member is movable in a reciprocated manner between a first extreme position and a second extreme position, whereby the fluid connection is closed, which first and second extreme positions are defined by an axial extend of a circumferential recess in the valve and the release position of the closing member is defined between the first and second closing positions and wherein the second subsurface forms a cavity in the plunger of the closing member;

and

wherein the device is arranged to be received in a cylindrical container, the first chamber being of cylindrical design having an outside diameter corresponding to the inside diameter of the container, so that the first chamber can be positioned adjacent the bottom of the container, while the second chamber is situated above the first chamber and in an inner space of the container located above the first chamber, which inner space, in use, is filled with the product to be dispensed.

11. A device according to claim 10, wherein at the first and second extreme positions, a gas seal is formed by contact between a first sealing ring and an outer edge of the closing member.

12. A device according to claim 10, wherein the closing member comprises a stem with the circumferential recess.

13. A device according to claim 10, wherein the plunger is sealed by an outer second sealing ring with respect to the inner wall of the second chamber.

14. A device according to claim 10, wherein the second chamber is located outside the first chamber.

15. A device according to claim 14, wherein the closing member is located substantially outside the first chamber.

16. A device according to claim 10, wherein the volume of the first chamber is substantially greater than the volume of the second chamber.

17. A container provided with a device according to claim 10.