Pressure relief device for an inflatable tire

• US 20070169818A1
• Filed: 11/04/2004
• Published: 07/26/2007
• Est. Priority Date: 11/04/2003
• Status: Abandoned Application

• Current Assignee: Opfinderfabrikken APS
• Original Assignee: Opfinderfabrikken APS
• Inventors: Badstue, Soren
• Application Number:
  US10/577,738
• Publication Number:
  US 20070169818A1
• Time in Patent Office: Days
• US Class Current: 137/225
• CPC Class Codes: B60C 29/06 Accessories for tyre-inflating valves, e.g. housings, guards, covers for valve caps, locks, not otherwise provided for B60C23/0496 takes precedence; tools for screwing and unscrewing valve caps B25B27/0057; pump connectors F04B33/005
• CPC Class Codes: B60C 29/068 Pressure relief devices, i.e. safety devices for overpressure
• CPC Class Codes: F16K 15/207 and combined with other valves, e.g. safety valves
• CPC Class Codes: Y10T 137/3631 Diaphragm, bellows or expansible tube

Abstract

A pressure relief device (100; 200, 300; 400; 400) for an inflatable tire comprises a body (102; 202; 302; 402; 502) having a chamber (124; 228; 324; 424; 524) with an inflation valve arranged in the body. An overpressure valve in the body releases air when the air pressure in the chamber exceeds a predetermined threshold pressure level. The overpressure valve includes at least one air conduit (128; 228; 328; 428; 528) extending from the chamber through the body in order to provide a passage to a surrounding atmosphere. A ring-shaped resilient member (130; 230; 330; 420; 530) is contractively fitted around an outer surface portion of the body, so as to keep the air conduit in a normally closed state. The properties and dimension of the resilient member are such that it is stretched when the air pressure in the chamber exceeds the predetermined pressure level, so as to provide an air passage from the conduit to the surrounding atmosphere. A plurality of pressure relief devices may be included in a kit, wherein the devices define different predetermined pressure levels.

Claims

1. A pressure relief device for an inflatable tire, comprising:

a body having a chamber therein and defining a circumferential outer surface portion;

an inflation valve arranged in the body;

an overpressure valve arranged in the body for releasing air when the air pressure in the chamber exceeds a first predetermined pressure level, said overpressure valve comprising;

at least one air conduit extending from said chamber through the body to said circumferential outer surface portion;

a ring-shaped resilient member which is contractively fitted around the circumferential outer surface portion, so as to keep the air conduit in a normally closed state;

the properties and dimensions of the resilient member being such that it is stretched when the air pressure in the chamber exceeds the first predetermined pressure level, so as to provide an air passage from the conduit to an exterior environment wherein a bottom portion of the body defines a cavity for receiving a valve of the tire centrally within the body, the cavity defining a threaded portion for screwing the device onto a threaded portion of a tire valve.

2. A device according to claim 1, wherein the resilient member is arranged in a reduced diameter section of the outer surface portion.

3. A device according to claim 1, wherein the overpressure valve further comprises a spring element arranged in the housing, the spring element exerting a closing force on a closure element, so that the closure element opens at a second predetermined pressure level.

4. A device according to claim 1, wherein the body comprises a weakened section, the properties of which are such that it breaks at a pressure which is higher than at least one of said first and second predetermined pressure level.

5. A device according to claim 1, further comprising a pin for releasing a stem of a tire valve, the pin being arranged to be able to slide axially in a first passageway in the body between a first position in which it cannot release the stem of the tire and a second position, in which it can release the stem, the body further defining a bypass passageway through which air may pass during inflation of the tire.

6. A device according to claim 1, further comprising a pin for releasing a stem of a tire valve, the pin being arranged to be able to slide axially in a first passageway in the body between a first position in which it cannot release the stem of the tire and a second position, in which it can release the stem, the pin having a head portion at that end of the device which is remote from the tire when the device is mounted to the tire, the head portion being arranged such that it abuts an inner collar portion of the body when the pin is in its first position.

7. A device according to claim 1, wherein a bottom portion of the body defines a cavity for receiving a valve of the tire centrally within the body, and wherein a top portion of the body is adapted to be connected to an inflation device, the air conduit being arranged radially displaced with respect to said cavity near the bottom portion.

8. A device according to claim 1, further comprising a protective cover for covering at least the top portion of the body, the cover being releasably connected to the cover.

9. A device according to claim 1, further comprising a pressure adjusting system for varying at least one of the first and the second predetermined pressure level.

10. A device according to claim 9, wherein the pressure adjusting system comprises means for varying a cross-sectional area of the air conduit.

11. A device according to claim 9, wherein the pressure adjusting system comprises means for varying a distortion of the resilient member.

12. A device according to claim 1, further comprising means for emitting an acoustic signal when the air pressure in the chamber exceeds at least one of the first and second predetermined pressure level.

13. A device according to claim 1, further comprising means for emitting an optical signal when the air pressure in the chamber exceeds at least one of the first and second predetermined pressure level.

14. A kit comprising a plurality of pressure relief devices according to claim 1, wherein the devices define different predetermined first and/or second pressure levels.

15. A kit according to claim 14, wherein each resilient member defines a coloured outer surface portion, and wherein the outer surface portions of the respective resilient members of the devices are coloured differently, the kit further comprising a list of colours and corresponding pressure levels.

16. A combination of a pressure relief device according to claim 1 and an inflatable tire.

17. A valve for inflation of a tire, the valve being integrated with a pressure relief device according to claim 1, so that the valve and the pressure relief device form one integrated unit.

18. A rim for an inflatable tire, the rim comprising a pressure relief device according to claim 1.

19. A rim according to claim 18, further comprising a valve for inflation of the tire, the valve being integrated with the pressure relief device, so that the valve and the pressure relief device form one integrated unit.

20. A wheel comprising a rim according to claim 18 and an inflatable tire.