Tire pressure monitor system with side entry pressure port

A tire pressure monitor system is provided including a sensor housing forming an internal housing mount chamber. An air inlet port is formed on a housing side surface and is orientated parallel to the wheel rim rotational axis. A sensor assembly including an air pressure sensor element is mounted within the internal housing mount chamber. A filter element and a gasket element are positioned between the air pressure sensor element and the air inlet port. A potting material fills the internal housing mount chamber. The filter element and the gasket element creating an air pressure flow path from the air inlet port to the air pressure sensor element.

TECHNICAL FIELD

The present invention relates generally to a tire pressure monitor system and more particularly to tire pressure monitor system with side entry pressure port for moisture intrusion protection.

BACKGROUND OF THE INVENTION

Automotive design and manufacturing has included an increasing quantity of consumer and performance features. These features provide a range of information regarding vehicle performance and function. Wherein many of these systems were traditionally either accomplished manually or required a physical wire connection to vehicle computers, more systems within the vehicle now operate through wireless transmission.

A feature that provides considerable challenges involves the monitoring of vehicle tire pressure. Correct tire pressure is highly desirable as it impacts vehicle handling, fuel economy, tire wear, etc. In order to properly monitor tire pressure, systems are commonly mounted within the tire and attached to either the valve stem or the wheel rim. These systems include pressure sensors and wireless transmitters to transmit individual pressures to a central computer. As the sensor assemblies are mounted within the wheel during vehicle operations, these systems must be extremely robust. Tire impact, high rotational speeds, and quick momentum shifts must all be accommodated. Therefore it is highly desirable for the sensor assemblies to be designed for extreme conditions.

Although momentum based stressors are of considerable concern, so additionally are environmental stressors. Vehicle wheel assemblies often are exposed to considerable environmental changes. Water or other fluids may accumulate within the wheel during routine operations. When the wheel is at a twelve o'clock or six o'clock position, such accumulation may adversely effect the sensor assembly if such fluid is allowed to enter the pressure inlet port of the sensor assembly. The sensor element itself may be permanently damaged should such fluid be allowed to contact the electronics. Therefore, it is highly desirable to have a tire pressure monitor assembly that was extremely robust and was resistant to fluid intrusion. Such a monitoring assembly would increase lifespan and reduce warranty costs.

SUMMARY OF THE INVENTION

In accordance with the desires of the present invention a tire pressure monitor system is provided including a sensor housing forming all internal housing mount chamber. An air inlet port is formed on a housing side surface and is orientated parallel to the wheel rim rotational axis. A sensor assembly including an air pressure sensor element is mounted within the internal housing mount chamber. A filter element and a gasket element are positioned between the air pressure sensor element and the air inlet port. A potting material fills the internal housing mount chamber. The filter element and the gasket element creating an air pressure flow path from the air inlet port to the air pressure sensor element.

Other objects and features of the present invention will become apparent when viewed in light of the detailed description and preferred embodiment when taken in conjunction with the attached drawings and claims.

DESCRIPTION OF PREFERRED EMBODIMENTS

Referring now toFIGS. 1 and 2, which is are illustrations of an tire pressure monitor system10in accordance with the present invention. It is contemplated that the tire pressure monitor system10is for use in automotive vehicles, although a variety of tire based applications may be obvious in light of the present disclosure. The tire pressure monitor system10is intended for installation into a wheel rim12having a wheel rim inner surface14and a wheel rim rotational axis16(seeFIG. 6). Although the tire pressure monitor system10may be installed onto the wheel rim12using a variety of methodologies, it is preferably contemplated that the system10is installed using a band attachment methodologies.

The tire pressure monitor system10includes a sensor housing18having an arched configuration suitable for engaging the wheel rim inner surface14. The sensor housing18is preferably molded to generate a housing upper surface20, a first housing end surface22, a second housing end surface24, a first housing side surface26and a second housing side surface28. The molded sensor housing18additionally generate an internal housing mount chamber30(seeFIG. 3). An air inlet port32is formed into the first housing side surface26and is configured such that upon installation of the tire pressure monitor system10, the air inlet port32will be orientated parallel to the wheel rim rotational axis16. This orientation prevents fluids accumulated around the wheel rim inner surface14from pooling and entering the air inlet port32. Additional, in at least one embodiment it is contemplated that the air inlet port32include a plurality of beveled inlet sidewalls34that further encourage moisture and fluids to flow away from the air inlet port32.

A sensor assembly36is mounted within the internal housing mount chamber30. The sensor assembly36is secured by a plurality of mount posts38formed within the internal housing mount chamber30. The sensor assembly36preferably is comprised of a circuit board40configured to house a battery element42and an air pressure sensor element44. Although a variety of air pressure sensor elements44are contemplated, one embodiment contemplates the use of a top port pressures sensor. In between the sensor element44and the air inlet port32is positioned a filter element46and a gasket element48. The filter element46is preferably pressed up against and in immediate contact with the air inlet port32. The gasket48, in turn, is pressed between the filter element46and the air pressure sensor element44. After these components are assembled, a potting material50is injected into the interior housing mount chamber30and cured. The potting material50surrounds the sensor assembly36, the filter element46and gasket48. The potting material50, however, cannot penetrate the filter element46or gasket48. Therefore, as the potting material50hardens, the filter element46and gasket48form an air pressure flow path52from the air inlet port32to the air pressure sensor element. A housing base54may be further utilized to encapsulate the sensor assembly36and potting material50within the internal housing mount chamber30.

Although the filter element46has been described generically, it is contemplated that the filter element46be comprised of a symmetrical filter element for ease of installation. It is additionally contemplated that in at least one embodiment, the filter element46be comprised of micro porous polytetrafluoroethylene. It is further contemplated that the filter element46may be comprised of a cross-shaped filter element46, seeFIG. 4, including a plurality of cross-arm portions56. By forming lead-in chamfers57on the cross-arm portions56the filter element46generates a slight interference with a housing filter chamber58formed in the internal housing mount chamber30to provide a seal against potting50leakage. In at least one embodiment, the gasket48works in combination with the housing filter chamber58to further reduce potting leakage.

The present invention further contemplates the use of a band mount brace60. The mount brace60is comprised of a first brace end62and a second brace end64. A plurality of hinge arms66are preferably formed in the first brace end62while a lock slot68is preferably formed in the second brace end64. These components are configured to mate with a plurality of hinge slots70formed on the first housing end surface22and at least one lock element72formed on the second housing end surface24. In this fashion, the first housing end surface22rotatably engages the first brace end62. The sensor housing18is rotated down until the lock element72engages the lock slot68and the sensor housing18is thereby secured to the band mount brace60. A position lock element74can then be inserted into a position chamber76formed in the sensor housing18to prevent disengagement of the lock element72from the lock slot68.

A first brace inlet78and a second brace inlet80are formed in the first brace end62and second brace end64respectively. These allow a band element82to be threaded through these inlets78,80and used to secure the tire pressure mount system10to the wheel rim inner surface14(seeFIG. 6). The orientation of the air inlet port32in combination with the beveled inlet sidewalls34prevents fluid intrusion through the inlet port32. The insertion and curing of the potting material50allows the filter element46and gasket48to automatically form internal plumbing for distribution of air from the air inlet port32to the air pressure sensor44.