Key fob seal structure with pressure release capability

The invention relates to automotive key fobs for remote keyless entry and, in particular, to a fob that releases internal pressure build-up due to environmental heating.

Conventional key fobs for remote keyless entry include an elastomeric seal to prevent liquids (e.g., water) from entering the fob. Due to the seal, pressure can build-up inside the fob due to environmental heating, such as by sun exposure, which may cause inadvertent opening of the fob.

Thus, there is a need to provide a fob that allows air to escape upon pressure build-up.

An object of the invention is to fulfill the needs referred to above. In accordance with the principles of the present invention, this objective is obtained by providing a self-venting device that includes a first component having an interior, a second component coupled to the first component so as to close the interior, and seal structure engaged between the first and second components in a sealed state so as to seal the interior from external agents. The seal structure includes a plurality of seal members, each having a resilient seal tip extending therefrom. The seal tips are constructed and arranged such that 1) when pressure inside the interior is equal to pressure outside of the device, the seal tips are compressed between the first and second components in the sealed state, and 2) when pressure in the interior is greater than the pressure outside of the device causing the second component to move away from the first component, the seal tips move to an unsealed state, permitting air to exit from the interior.

In accordance with another aspect of a disclosed embodiment, a method vents a device having a first component and second component. The method provides seal structure engaged between the first and second components in a sealed state so as to seal the interior from external agents, such that when pressure inside the interior is equal to pressure outside of the device, a resilient portion of the seal structure is compressed between the first and second components in the sealed state. When pressure in the interior is greater than the pressure outside of the device causing the second component to move away from the first component, the method ensures that the resilient portion of the seal structure moves to an unsealed state, permitting air to exit from the interior.

Other objects, features and characteristics of the present invention, as well as the methods of operation and the functions of the related elements of the structure, the combination of parts and economics of manufacture will become more apparent upon consideration of the following detailed description and appended claims with reference to the accompanying drawings, all of which form a part of this specification.

The invention will be better understood from the following detailed description of the preferred embodiments thereof, taken in conjunction with the accompanying drawings, wherein like reference numerals refer to like parts, in which:

FIG. 1 is a cross-sectional view of a key fob for a vehicle, shown with a cover removed from a body and with seal structure, in a relaxed state, provided in accordance with an embodiment.

FIG. 2 is a view of the key fob of FIG. 1 , but shown with the cover coupled to the body and compressing seal tips of the seal structure.

FIG. 3 is a view of the key fop of FIG. 2 , but shown with pressure increase in an interior of the fob causing the seal tips of the seal structure move to an unsealed state, thereby permitting air to exit the interior.

FIG. 4 is a view of a key fob having seal structure provided in accordance with another embodiment.

With reference to FIG. 1 , a self-venting device in the form of a key fob is shown generally indicated at 10 , for remote keyless entry of a vehicle. The fob 10 includes a first component in the form of a body 12 having an interior 14 . A second component in the form of a cover 16 is attached to the body 12 so as to close the interior 14 . The cover 16 is removable from the body 12 to gain access to the interior 14 of the fob, for example, to change a battery therein. In FIG. 1 , the cover 16 is shown removed from the body 12 .

In accordance with an embodiment, seal structure, generally indicated at 18 , is provided between and engaged with a portion of the cover 16 and a portion of the body 12 in a sealed state to provide an axial airtight seal for the interior 14 against external environmental agents. The seal structure 18 is preferably an elastomer O-ring, having a plurality of seal members, generally indicated at 19 , with each seal member including a resilient seal tip 20 that extends from a base 22 in a cantilever manner. FIG. 1 shows the seal tips 20 in a relaxed state. In the embodiment, in cross-section, each seal member 19 is of generally triangular shape, with the seal tip 20 defining an apex. A plurality of adjacent seal members 19 define a generally saw-tooth structure.

With reference to FIG. 2 , the seal tips 20 are constructed and arranged such that when pressure inside the interior 14 is equal to pressure outside of the fob 10 , the seal tips 20 are compressed (e.g., bent) between the body 12 and the cover 16 to maintain the sealed state between the body 12 and the cover 16 . With reference to FIG. 3 , when pressure in the interior 14 is greater than the pressure outside of the fob 10 (e.g., from exposure to the heat of the sun) causing the cover 16 to move away from the body 12 , the seal tips 20 automatically move minutely to an unsealed state (a state of less or no compression), permitting air to exit from the interior 14 by escaping around the perimeter of the seal structure 18 . Once the pressure build-up in the interior 14 is relieved, the cover 16 automatically moves back to its normal position, compressing the seal tips 20 , returning the seal structure 18 to its sealed state.

FIG. 4 shows another embodiment of a key fob 10 ′ with the seal structure 18 ′ providing a radial seal between the cover 16 ′ and the body 12 ′.

Thus, the seal structure 18 provides self-venting (pressure relief) of the key fob 10 in addition to providing highly reliable sealing at no additional cost.

The foregoing preferred embodiments have been shown and described for the purposes of illustrating the structural and functional principles of the present invention, as well as illustrating the methods of employing the preferred embodiments and are subject to change without departing from such principles. Therefore, this invention includes all modifications encompassed within the spirit of the following claims.