Patent Application
20060202881
The present invention relates to remote keyless entry systems for vehicles, and in particular to a key fob of a remote keyless entry system.
Remote keyless entry (RKE) systems for vehicles enjoy wide use today, with RKE systems adding additional functions over and above the more conventional lock/unlock, trunk release and alarm functions. Such functions may include, for example, power door open/close and remote engine start. Typically, the conventional key fob transmits a vehicle function request whenever a button is pressed, whether inadvertent or not.
In addition, some RKE systems employ a passive key fob where certain vehicle functions are performed based on, for example, the proximity and direction of movement of the key fob relative to the vehicle, rather than only reacting to the actuation of a button. While most functions are performed on these passive devices without the need to press a button, there may be buttons on them for the infrequent occasion when the user wishes to activate a vehicle function outside of the normal passive activation parameters. But again, inadvertent pressing of a button can cause a vehicle function to be performed even when the operator does not wish it to be.
For some, a RKE function being performed when a button is inadvertently pressed is a significant annoyance. For example, when a key fob is in ones pocket or purse, an alarm or trunk release button may be inadvertently pressed, causing the key fob to transmit the requested vehicle function even if not desired by the one carrying the key fob. One may then have to pull out the key fob and press the button again or go over to the vehicle to counteract the inadvertent vehicle function performed.
Thus, it is desirable to provide a way to limit the potential for inadvertently actuating the buttons on a key fob while still allowing for quick and easy access to the buttons when desired by the user.
An embodiment of the present invention contemplates a key fob for use in a remote keyless entry system of a vehicle. The key fob may include a transmitter housing having one or more user operable buttons thereon indicative of a remote keyless entry function associated with the vehicle for transmitting a function request when the user operable button is depressed. The key fob may also include a cover retained on the transmitter housing and slidably movable between an open position exposing the one or more buttons and a closed position wherein the one or more buttons are covered by the cover. A biaser is coupled between the transmitter housing and the cover such that the biaser urges the cover toward the open position, and a catch mechanism selectively and releasably secures the cover in the closed position against the bias of the biaser.
An advantage of an embodiment of the present invention is that the key fob includes a cover for protecting user operable buttons from inadvertent actuation, while also providing a simple, convenient, automatic cover release for quick and easy access to the buttons when desired.
A further advantage of an embodiment of the present invention is that the quick and easy access to the user operable buttons on the key fob are provided while still retaining the cover to the transmitter housing at all times, thus avoiding the potential for the cover to become separated from the housing and lost. Moreover, once the user no longer needs access to the buttons, the cover is easily moved to and retained in its closed position until the next time the user wishes to access the buttons.
An additional advantage of an embodiment of the present invention is that the catch mechanism, for holding the cover in its closed position, the automatic release, for biasing the cover to its open position, and the stop, for retaining the cover to the housing, are all relatively inexpensive to fabricate and assemble, thus minimizing the cost of the key fob.
The RKE system 20 also includes a key fob 22. The term “key fob” as used herein includes both a conventional key fob—where a signal is only transmitted to the vehicle when a button is pressed—as well as a passive remote keyless entry, remote start, keyless ignition, etc. type transmitter (also called passive remote function actuator)—where certain functions may be performed without any user input based on, for example, the proximity and motion of the device relative to the vehicle. For the latter type of key fob this invention may be particularly advantageous since the user buttons on the key fob may be rarely used.
The key fob 22 has a transmitter housing 24. Within the transmitter housing 24, the key fob 22 may include a fob controller (not shown), powered by a battery (not shown), and a transmitter (not shown), capable of transmitting a radio frequency (RF) signal that can be received by the receiver in the vehicle. The transmitter of course may be a transceiver if the RKE system 20 includes two-way communication, and may transmit the signal by wireless means other than by RF transmission, if so desired. The details of the fob controller, transmitter and other electronic circuitry of the key fob 22 will not be discussed in detail herein since they are known to those skilled in the art.
The transmitter housing 24 has a front side 26 and a back side 28, and also has a recessed portion 30 that has smaller dimensions than a main portion 31. On the front side 26 of the main portion 31 is a first user release location 46, with the general size and position shown in phantom in
On the front side 26, in the recessed portion 30 of the housing 24, first 32, second 34, and third 36 user operable buttons are located. The vehicle functions associated with these buttons 32, 34, 36, may include, for example, door lock, door unlock, trunk release, engine start, door open, door close, alarm, etc. as is desired for the particular vehicle and RKE system 20. The operation of these vehicle functions will not be discussed as they are known to those skilled in the art. This recessed portion 30 may also have a light emitting diode (LED) 37 located therein that may be activated, for example, to indicate a particular function is being performed, to indicate a low battery condition, etc.
Also located in and extending outward from the recessed portion 30 of the housing 24 are a lock rib 38 and a stop pin 40. The lock rib 38 extends widthwise across the recessed portion 30 adjacent to the main portion 31 of the housing 24. The stop pin 40 is positioned so that it will be located under and in contact with a cover 50, whether the cover 50 is in its closed or open position. The recessed portion 30 of the housing 24 also includes a pair of spring retention recesses 42, within which are mounted a pair of compression springs 44. While two springs 44 are illustrated, the key fob 22 may incorporate only one spring 44 and one spring retention recess 42 instead, if so desired. Also, other means of providing a biasing force similar to the springs may be employed instead of the springs, if so desired.
The cover 50 of the key fob 22 fits over and is slidable relative to the transmitter housing 24. The cover 50 has a front wall 52, which extends across the front side 26 of the recessed portion 30, a pair of side walls 54 and a back wall 58, which help to maintain the orientation of the cover 50 when sliding between the open and closed position, and an end wall 56, which is in surface contact with the springs 44.
The front wall 52 of the cover 50 includes a lock catch 60 and a stop slot 62, and may include a LED viewing window 64. The lock catch 60 is a recess in the front wall 52 that is sized slightly longer and slightly wider than the lock rib 38, and is located so that it aligns with the lock rib 38 when the cover 50 is in its closed position. The lock rib 38 extends outward sufficiently from the front side 26 of the recessed portion 30 that it will extend into the lock catch 60 when the two are aligned. Accordingly, with the lock rib 38 engaged in the lock catch 60, the cover 50 can be held closed against the bias of the springs 44.
The stop slot 62 is a recess in the front wall 52 that has a width about the diameter of the stop pin 40 and a length that is at least as long as the diameter of the stop pin 40 plus the distance traveled by the cover 50 between its closed and open positions. The stop slot 62 includes a stop end 66 that is located to engage with the stop pin 40 when the cover 50 is in its open position. Thus, the engagement of the stop pin 40 with the stop end 66 of the stop slot 62 acts as a travel limiter 67, preventing the cover 50 from being pushed all of the way off the end of the housing 24 by the springs 44. As an alternative, the stop pin may be located on and extending from the cover while the stop slot is located on the housing.
The LED viewing window 64 is located to align with the LED when the cover 50 is in the closed position and may be just a hole through the front wall 52 or may also include a transparent material covering the hole. Thus, even though the buttons 32, 34, 36 are covered when the cover 50 is in its closed position, the user of the key fob 22 can still see when the LED is lit.
While the lock catch 60 and stop slot 62 are illustrated as slots recessed in the cover front wall 52, either or both may instead be formed from flanges extending outwardly from the cover front wall 52 that partially or fully surround the lock rib 38 and stop pin 40, respectively. Also, while the cover 50 is shown completely wrapping around the front and back sides 26, 28 of the housing 24, it may also wrap only partially around the back 28, if so desired. And, while the cover 50 is shown sliding over the recessed portion 30 of the housing 24 in order to provide a smooth surface when closed, the housing 24 may be the same size along its length (i.e., no recess) with the cover 50 being larger and sticking out somewhat from the housing 24.
The operation of the key fob 22 will now be described. In operation, when the user desires to access the user operable buttons 32, 34, 36, the user merely squeezes on the front and back sides 26, 28 of the transmitter housing 24 in proximity to the edge of the cover 50 near the center of each side 26, 28. That is, the transmitter housing 24 is squeezed at about the first and second user release locations 46, 48. There is a gap (not shown) between the front side 26 and back side 28 so, when squeezed, the front side 26 will flex. This flexing will cause the lock rib 38 to release from the lock catch 60, thus allowing the compression springs 44 to automatically slide the cover 50 from its closed to its open position. The stop pin 40 will hit the stop end 66 of the stop slot 62, thus preventing the springs 44 from shooting the cover 50 all of the way off the end of the housing 24. With the cover 50 in its open position, the user has full access to all of the user operable buttons 32, 34, 36.
After the user is done using the buttons 32, 34, 36, he merely slides the cover 50 against the bias of the springs 44 back into its closed position where the lock catch 60 will automatically engage the lock rib 38 and hold the cover 50 in its closed position against the bias of the springs 44. Preferably, the lock rib 38 is sized and located relative to the lock catch 60 so that it will snap into the lock catch 60 sufficient to cause audible and tactile feedback for the user to confirm that the cover 50 is locked in its closed position. With the cover 50 now in its closed position, the buttons 32, 34, 36 cannot be inadvertently actuated by the user.
While certain embodiments of the present invention have been described in detail, those familiar with the art to which this invention relates will recognize various alternative designs and embodiments for practicing the invention as defined by the following claims.
