Tire-mounted air pressure gauge assembly

• US 4,924,697 A
• Filed: 10/05/1988
• Issued: 05/15/1990
• Est. Priority Date: 01/11/1988
• Status: Expired due to Term

• Current Assignee: John F. Mcdaniel
• Original Assignee: Permanent Tire Gauge Company Incorporated
• Inventors: McDaniel, John F., Hunt, Glen R.
• Primary Examiner(s): WOODIEL, DONALD
• Application Number:
  US07/253,976
• Time in Patent Office: 587 Days
• Field of Search: 73/146.8, 73/146.5, 73/146.2, 73/146, 73/741, 73/742, 73/743, 137/227, 137/228, 137/229
• US Class Current: 73/146.8
• CPC Class Codes: B60C 23/007 having multiple wheels arranged side by side
• CPC Class Codes: B60C 23/0405 Mechanically generated visible signals, e.g. by using a gauge needle
• CPC Class Codes: B60C 23/0496 Valve stem attachments positioned outside of the tyre chamber

Abstract

The present invention is an improvement to a tire mounted air pressure gauge for use on vehicles having inflatable tires. The air pressure gauge has a dial face, with a coiled pressure responsive spring expandable to indicate the pressure detected by the gauge. The gauge is mounted directly onto the valve stem of a tire to detect the pressure in the tire, or is mounted onto the valve steam via an L-shaped conduit. The conduit contains a lug adapted to depress the conventional valve core of the valve stem and release air pressure within the valve stem and tire. An arc-shaped or cylindrical retainer is provided on the dial face to limit radial expansion of the coiled spring due to centrifugal forces of the rotating tire and other jarring forces exerted on the pressure gauge during use of the tire.

Claims

1. A tire-mounted air pressure gauge assembly for use on vehicles having inflatable tires wherein each tire has a valve stem with a conventional valve core therein, the pressure gauge assembly comprising:

an air pressure gauge having a dial face with a light-reflective background which covers substantially the entire dial face and has contrasting pressure indicia thereon for indicating the air pressure detected by the gauge; and

an adapter having means for affixing the gauge to the valve stem with an airtight connection, including means for depressing the valve core of the valve stem to allow air and pressure from the tire to pass through the adapter and to the gauge, with the adapter shaped to present the dial face in direction away from that portion of the tire adjacent the valve stem.

2. In combination with a tire pressure gauge and a wheel having an inflatable tire mounted thereon, the tire having a valve stem with a conventionally depressible valve core therein, the valve stem extending longitudinally from a first side of said tire in direction generally parallel to the tire'"'"'s rotational axis, toward a second opposite side of said tire and through an aperture in the wheel, the improvement which comprises:

the gauge being a dial-type gauge having a dial face with a light-reflective background which covers substantially the entire dial face and has contrasting pressure indicia thereon and a pressure responsive indicator needle pivotally mounted with respect to the dial face; and

an air pressure conduit threadably and sealably mounted at a first end thereof onto the valve stem and sealably connected at a second end thereof to the tire pressure gauge, the first end of the conduit having means for continuously depressing the valve core of the valve stem to allow air pressure from the tire to bleed through the conduit to the tire pressure gauge, and the conduit formed and aligned to readably present the dial face of the tire pressure gauge through said aperture in the wheel to an operator positioned on the first side of the tire.

3. The invention of claim 2 wherein the indicator needle is mounted on a coiled pressure responsive spring which expands under pressure, and wherein the pressure gauge has retainer means for limiting radial expansion of the coiled spring beyond a desired radial expansion limit.

4. For use with a tire-mounted air pressure gauge which has a spring chamber, a coiled spring responsive to tire air pressure mounted within the spring chamber and a pressure indicator needle mounted on the outer end of the coiled spring to extend radially outwardly therefrom, the improvement which comprises:

arc-shaped wall means mounted within the spring chamber, the wall means being aligned between the coiled spring and an inner wall surface of the spring chamber for engaging an arcuate portion of the coiled spring to prevent radial expansion of the coiled spring beyond a predetermined radius and thus prevent the pressure indicator needle from contacting the inner wall surface of the spring chamber.

5. The invention of claim 4 wherein the arc-shaped wall means traverses an arc of at least 180°

.

7. The invention of claim 4 wherein the arc-shaped wall means comprises a cylindrical wall coaxially aligned about the coiled spring.

6. For use with a tire-mounted air pressure gauge which has a coiled spring responsive to tire air pressure, a dial face and a transparent cover portion thereover, the improvement which comprises:

arc-shaped wall means formed integrally with the cover portion, with the arc-shaped wall means radially spaced from a most outward section of the coiled spring of the gauge for engaging an arcuate portion of the coiled spring to prevent radial expansion of the coiled spring beyond a predetermined radius.

8. For use with a tire-mounted air pressure gauge which has a coiled spring with a pressure indicator needle mounted thereon, wherein the coiled spring is responsive to tire air pressure, the improvement which comprises:

arc-shaped wall means, having first and second ends, radially spaced from a most outward section of the coiled spring of the gauge for engaging an arcuate portion of the coiled spring to prevent radial expansion of the coiled spring beyond a predetermined radius; and

a radially extending wing portion secured to each end of the wall means to extend outwardly therefrom in position to engage the pressure indicator needle.

9. An air pressure gauge for use on an inflatable tire which has a valve stem with a conventionally depressible valve core therein, the pressure gauge comprising:

a base portion threadably and sealably mounted on a valve stem;

means for depressing the valve core of the valve stem when the base portion is mounted on the valve stem;

a gauge housing mounted with respect to the base portion and having a spring chamber defined therein;

a coiled pressure responsive tube mounted within the spring chamber of the housing for communication with the valve stem through the base portion, the coiled tube being expandable under pressure; and

arc-shaped retainer means mounted coaxially with respect to the coiled tube and aligned between the coiled spring and an inner wall surface of the spring chamber for limiting radial expansion of the coiled tube beyond a desired radial expansion limit defined by the radius of the arc-shaped retainer means.

10. For use with a tire-mounted air pressure gauge of the type having a coiled spring responsive to tire air pressure and an indicator needle secured to a radially outward end of the coiled spring, the improvement comprising:

retainer means for preventing expansion of the coiled spring beyond a predetermined radius, the retainer means including an arc-shaped wall radially spaced from a most outward section of the coiled spring of the gauge for limiting radial expansion of the coiled spring, and first and second wing portions integrally formed with the annular wall and extending generally radially outward from the wall for engaging the indicator needle.

11. For use with a tire-mounted air pressure gauge of the type having a spring chamber and a coiled spring responsive to tire air pressure mounted within the spring chamber, the improvement comprising:

cylindrical retainer wall means coaxially positioned with respect to the coiled spring and aligned between the coiled spring on an inner wall surface of the spring chamber for engaging the coiled spring when a predetermined radial expansion limit thereof has been reached, thereby preventing unlimited radial expansion and operative distortion of the coiled spring.

12. For use with a tire-mounted air pressure gauge which as a coiled spring with a pressure indicator needle mounted thereon, wherein the coiled spring is responsive to tire air pressure, the improvement which comprises:

arc-shaped wall means, having first and second ends, radially spaced from a most outward section of the coiled spring of the gauge for engaging an arcuate portion of the coiled spring to prevent radial expansion of the coiled spring beyond a predetermined radius; and

a radially extending wing portion secured to one end of the wall means to extend outwardly therefrom in position to engage the pressure indicator needle.