Pressure gauge for vehicle tires

• US 6,374,666 B1
• Filed: 03/10/2000
• Issued: 04/23/2002
• Est. Priority Date: 03/10/2000
• Status: Expired due to Fees

• Current Assignee: The Tire Chef Inc.
• Original Assignee: The Tire Chef Inc.
• Inventors: Anthony, Michael M., Lemberger, Gary
• Primary Examiner(s): Oen, William
• Assistant Examiner(s): AW MUSSE, ABDULLAHI H
• Application Number:
  US09/523,470
• Time in Patent Office: 774 Days
• Field of Search: 731/468, 731/462, 731/465, 737/15, 116/30.R, 137/224, 137/225
• US Class Current: 73/146.8
• CPC Class Codes: B60C 23/0496 Valve stem attachments positioned outside of the tyre chamber

Abstract

A tire pressure gauge apparatus for securing to a vehicle tire valve stem mounted to a tire valve stem port in a vehicle tire, the valve stem including a tubular stem body containing a valve assembly having a valve opening mechanism, the stem body having a stem connection end fitting sealingly to the tire valve stem port, and having a stem air receiving end, the apparatus including a housing for placement in fluid communication with received air from within the tire contained within the tire valve stem; a structure for opening the valve opening mechanism; and a pressure equilibration structure dividing the housing into a received air chamber and a biasing air chamber and including a pressure indicator element, the pressure equilibration structure and the pressure indicator element being movable relative to the housing, and the pressure indicator element displaying a pressure reading of received air from within the tire which varies with the position of the pressure equilibration structure relative to the housing; so that alteration of the pressure of received air within the received air chamber from the valve stem causes movement of the equilibration structure within the housing to re-establish pressure equilibrium between biasing air sealed within the biasing air chamber and received air within the received air chamber, and movement of the equilibration structure causes the indicator element to move relative to the housing to provide a received air pressure reading.

Claims

1. A tire pressure gauge apparatus for securing to a vehicle tire valve stem mounted to a tire valve stem port in a vehicle tire, the valve stem including a tubular stem body containing a valve assembly having a valve opening means, the stem body having a stem connection end fitting sealingly to the tire valve stem port, and having a stem air receiving end, the apparatus comprising:

a housing for placement in fluid communication with received air from within the tire contained within the tire valve stem;

means for opening said valve opening means;

and a pressure equilibration structure dividing said housing into a received air chamber and a biasing air chamber and comprising a pressure indicator element, said pressure equilibration structure and said pressure indicator element being progressively movable relative to said housing and thereby substantially continuously maintaining and re-establishing pressure equilibrium between air within said received air chamber and air within said biasing air chamber, and said pressure indicator element displaying a pressure reading of received air from within the tire which varies with the position of said pressure equilibration structure relative to said housing;

such that alteration of the pressure of received air within said received air chamber from the valve stem causes movement of said equilibration structure within said housing to re-establish pressure equilibrium between biasing air sealed within said biasing air chamber and received air within said received air chamber, and movement of said equilibration structure causes said indicator element to move relative to said housing to provide a received air pressure reading.

2. A tire pressure gauge apparatus for securing to a vehicle tire valve stem mounted to a valve stem port in a vehicle tire, the valve stem including a tubular stem body containing a valve assembly having an outwardly biased valve opening shaft, the stem body having a stem connection end with a circumferential groove for fitting sealingly into an edge of the tire valve stem port, and having a stem air receiving end having external threads for affixation of a valve stem cap and having internal threads into which the valve assembly is screwed, the apparatus comprising:

a housing for placement in fluid communication with received air from within the tire contained within the tire valve stem;

means for depressing said valve opening shaft and thereby opening said valve assembly, said means for depressing being connected to said housing;

and a pressure equilibration structure dividing said housing into a received air chamber and a biasing air chamber and comprising a pressure indicator element, said pressure equilibration structure and said pressure indicator element being progressively movable relative to said housing, and thereby substantially continuously maintaining and re-establishing pressure equilibrium between air within said received air chamber and air within said biasing air chamber and said pressure indicator element displaying a pressure reading of received air from within the tire which varies with the position of said pressure equilibration structure relative to said housing;

such that alteration of the pressure of received air within the received air chamber from the valve stem causes movement of said equilibration structure within the housing to re-establish pressure equilibrium between biasing air sealed within said biasing air chamber and received air within said received air chamber, and movement of said equilibration structure causes said indicator element to move relative to said housing to provide a received air pressure reading.

3. The gauge apparatus of claim 2, wherein said housing is a tubular housing having an open connection end and a closed indicator display end, said biasing air chamber including an indicator display window and terminating in an integral housing end wall;

and wherein said pressure equilibration structure comprises a diaphragm panel and said indicator element comprises an indicator cylinder marked with calibrations and secured to said diaphragm panel and extending into said biasing air chamber and passing adjacent to said indicator display window, said diaphragm panel being sized in diameter to fit within said housing and being sealingly and circumferentially joined to the inner surface of said housing;

means for sealingly securing said diaphragm panel to said step;

valve opening shaft depression means for depressing the valve opening shaft to release air from within the tire into said received air chamber;

means for securing the valve stem body to and in fluid communication with said received air chamber;

such that the apparatus is screwed onto the stem air receiving end to create a seal between said received air chamber and the valve stem body, and such that the valve opening shaft depression means depresses the valve opening shaft to an extent which opens the valve assembly to pass air from within the tire into said received air chamber and against said diaphragm panel; and

such that pressure of received air from within the tire deflects said diaphragm panel toward said biasing air chamber, thereby compressing the biasing air until the pressure of the biasing air rises to equal the pressure of the received air within the received air chamber, whereupon the attached indicator cylinder comes to rest to indicate the pressure of air contained within said received air chamber and within the tire.

4. The gauge apparatus of claim 3, wherein said calibrations are circumferential color bands.

5. The gauge apparatus of claim 3, wherein said calibrations are lines labeled with pressure reading figures.

6. The gauge apparatus of claim 2, wherein said housing is a tubular housing having an open connection end and a closed indicator display end, said biasing air chamber including an indicator display window and an integral housing end wall;

and wherein said indicator element comprises an indicator cylinder dividing said biasing air chamber from said received air chamber and being slidably mounted within said housing to slide into and out of said biasing air chamber, said indicator cylinder being marked with calibrations and passing adjacent to said indicator display window;

valve opening shaft depression means for depressing the valve opening shaft to release air from within the tire into said received air chamber;

means for securing the valve stem body to and in fluid communication with said received air chamber;

such that the apparatus is screwed onto the stem air receiving end to create a seal between said received air chamber and the valve stem body, and such that the valve opening shaft depression means depresses the valve opening shaft to an extent which opens the valve assembly to pass air from within the tire into said received air chamber and against said indicator cylinder; and

such that pressure of received air from within the tire slides said indicator cylinder into said biasing air chamber, thereby compressing the biasing air until the pressure of the biasing air within the biasing air chamber rises to equal the pressure of the received air within the received air chamber, whereupon the indicator cylinder comes to rest to indicate the pressure of air contained within said received air chamber and within the tire.

7. The gauge apparatus of claim 2, wherein said housing is a tubular housing having an open connection end and a closed indicator display end, said biasing air chamber including an indicator display window and terminating in an integral housing end wall;

and wherein said pressure equilibration structure comprises a partition wall having a partition wall air passing port and an indicator bellows secured to said partition wall over said partition wall air passing port and extending into said biasing air chamber, said indicator bellows being axially expandable into said biasing air chamber, said indicator bellows being marked with calibrations and passing adjacent to said indicator display window;

valve opening shaft depression means for depressing the valve opening shaft to release air from within the tire into said received air chamber and into said indicator bellows;

means for securing the valve stem body to and in fluid communication with said received air chamber;

such that the apparatus is screwed onto the stem air receiving end to create a seal between said received air chamber and the valve stem body, and such that the valve opening shaft depression means depresses the valve opening shaft to an extent which opens the valve assembly to pass air from within the tire into said received air chamber and into said indicator bellows; and

such that pressure of received air from within the tire expands said indicator bellows into said biasing air chamber, thereby compressing the biasing air until the pressure of the biasing air within said biasing air chamber rises to equal the pressure of the received air within said received air chamber, whereupon the attached indicator bellows ceases to expand, and indicates the pressure of air contained within said received air chamber and tire.

18. The apparatus of claim 3, wherein said tubular housing comprises an abrupt reduction in diameter between said connection end and said indicator display end defining a housing step forming a housing shoulder, such that said housing connection end is a wider housing tube segment defining said received air chamber and said housing indicator display end is a narrower housing tube segment defining said biasing air chamber;

and wherein said diaphragm panel is secured sealingly against said housing shoulder.

19. The apparatus of claim 6, wherein said tubular housing comprises an abrupt reduction in diameter between said connection end and said indicator display end defining a housing step, such that said housing connection end is a wider housing tube segment defining said received air chamber and said housing indicator display end is a narrower housing tube segment defining said biasing air chamber.

8. A tire pressure gauge and valve stem apparatus for securing into a valve stem port in a vehicle tire, comprising:

a vehicle tire valve stem comprising a tubular stem body containing a valve assembly, said stem body having a stem connection end with means for fitting sealingly into a tire valve stem port, and having a stem air receiving end;

a gauge housing secured to said valve stem body in fluid communication with received air contained within said valve stem body through a valve stem body lateral opening;

and a pressure equilibration structure dividing said housing into a received air chamber and a biasing air chamber and comprising a pressure indicator element, said pressure equilibration structure and pressure indicator element being progressively movable relative to said housing and thereby substantially continuously maintaining and re-establishing pressure equilibrium between air within said received air chamber and air within said biasing air chamber and displaying a pressure reading of received air from within the tire which varies with the position of the pressure equilibration structure relative to the housing;

such that alteration of the pressure of received air within the received air chamber causes movement of said pressure equilibration structure within the housing to re-establish pressure equilibrium between biasing air sealed within said biasing air chamber and received air within said received air chamber, and movement of said equilibration structure causes said indicator element to move relative to said housing to provide a received air pressure reading.

9. The apparatus of claim 8, wherein said housing is a tubular housing having a connection end secured to a side of said valve stem body and a closed indicator display end, said biasing air chamber including an indicator display window and terminating in an integral housing end wall;

and wherein said pressure equilibration structure comprises a diaphragm panel and said indicator element comprises an indicator cylinder marked with calibrations and secured to said diaphragm panel and extending into said biasing air chamber and passing adjacent to said indicator display window, said diaphragm panel being sized in diameter to fit within said housing and being sealingly and circumferentially joined to the inner surface of said housing;

and means for sealingly securing said diaphragm panel to said step;

such that pressure of received air from within the tire deflects said diaphragm panel toward said biasing air chamber, thereby compressing the biasing air until the pressure of the biasing air within the biasing air chamber rises to equal the pressure of the received air within the received air chamber, whereupon the attached indicator cylinder comes to rest to indicate the pressure of air contained within said received air chamber and within the tire.

10. The gauge apparatus of claim 9, wherein said calibrations are circumferential color bands.

11. The gauge apparatus of claim 9, wherein said calibrations are lines labeled with pressure reading figures.

12. The gauge apparatus of claim 8, wherein said housing is a tubular housing having a connection end secured to a side of said valve stem body and a closed indicator display end, said biasing air chamber including an indicator display window and terminating in an integral housing end wall;

and wherein said indicator element comprises an indicator cylinder dividing said biasing air chamber from said received air chamber and being slidably mounted within said housing to slide into and out of said biasing air chamber, said indicator cylinder being marked with calibrations and passing adjacent to said indicator display window;

such that pressure of received air from within the tire slides said indicator cylinder into said biasing air chamber, thereby compressing the biasing air until the pressure of the biasing air within the biasing air chamber rises to equal the pressure of the received air within the received air chamber, whereupon the indicator cylinder comes to rest to indicate the pressure of air contained within said received air chamber and within the tire.

13. The gauge apparatus of claim 12, wherein said calibrations are circumferential color bands.

14. The gauge apparatus of claim 12, wherein said calibrations are lines labeled with pressure reading figures.

15. The gauge apparatus of claim 8, wherein said housing is a tubular housing having a connection end and a closed indicator display end, said biasing air chamber including an indicator display window and terminating in an integral housing end wall;

and wherein said pressure equilibration structure comprises a partition wall having a partition wall air passing port and an indicator bellows secured to said partition wall over said partition wall air passing port and extending into said biasing air chamber, said indicator bellows being axially expandable into said biasing air chamber, said indicator bellows being marked with calibrations and passing adjacent to said indicator display window;

such that pressure of received air from within the tire expands said indicator bellows into said biasing air chamber, thereby compressing the biasing air until the pressure of the biasing air within said biasing air chamber rises to equal the pressure of the received air within said received air chamber, whereupon the attached indicator bellows ceases to expand and achieves a substantially fixed position relative to said housing to indicate the pressure of air contained within said received air chamber and within the tire.

20. The apparatus of claim 9, wherein said tubular housing comprises an abrupt reduction in diameter between said connection end and said indicator display end defining a housing step forming a housing shoulder, such that said housing connection end is a wider housing tube segment defining said received air chamber and said housing indicator display end is a narrower housing tube segment defining said biasing air chamber;

and wherein said diaphragm panel is secured sealingly against said housing shoulder.

16. A tire pressure gauge and valve stem apparatus for securing into a valve stem port in a vehicle tire, comprising:

a vehicle tire valve stem comprising a tubular stem body containing a valve assembly, said stem body having an outer surface and having a stem connection end with means for fitting sealingly into a tire valve stem port, and having a stem air receiving end;

a gauge housing comprising a housing circumferential wall formed of a translucent material and bowed outwardly from said circumferential wall along the longitudinal axis of said housing circumferential wall and wrapped sealingly and circumferentially around said valve stem body; and

wherein said equilibration structure is an elastic bladder contained within said housing circumferential wall and wrapped circumferentially around and sealingly secured to the outer surface of said tubular stem body;

a stem branch passageway extending laterally from the interior of said stem body and opening within said bladder;

and a substantially opaque liquid contained within an annular space defined between said bladder and said housing circumferential wall together with a certain quantity of biasing air;

the quantity and pressure of the biasing air and the elastic resistance of said bladder in relation to the minimum adequate tire air pressure being such that a tire air pressure of at least a certain magnitude which is deemed adequate causes said bladder to expand radially, to compress the biasing air and to displace said substantially opaque liquid and bear against the inner surface of said housing circumferential wall, making a portion of said bladder visible through said housing circumferential wall, and such that a tire air pressure of less than the certain magnitude deemed adequate permits the elasticity of said bladder and the pressure of said biasing air to retract said bladder from contact with said housing circumferential wall and said substantially opaque liquid to flow between said bladder and said circumferential wall to obscure said bladder from view.

17. The apparatus of claim 16, wherein said bladder is brightly pigmented and wherein said opaque liquid is darkly pigmented for increased visual contrast between said bladder and said opaque liquid for greater bladder visibility when said bladder bears against said housing circumferential wall.