Patent Publication Number: US-2006005590-A1

Title: Mechanical door handle switch assembly with a dampening mechanism

Description:
BACKGROUND OF INVENTION  
      The present application relates to another application entitled “MECHANICAL HANDLE SWITCH ASSEMBLY,” filed concurrently herewith the specification of which is hereby incorporated by reference.  
      The present invention relates generally to a door handle switch, and more particularly to a mechanical door handle switch having a simple robust construction for ease of manufacture, efficient installation, low power consumption, and substantially lower costs associated therewith.  
      Passive entry systems for providing access to the interior of a vehicle are well known. A typical passive entry system utilizes radio frequency identification technology. One known passive entry system includes a vehicle-based transceiver and a portable transponder, which is carried by an authorized user. This system typically includes an electronic sensor for detecting the actuation of a door handle by an individual who intends to enter the vehicle. In this regard, the electronic sensor can detect door handle acutation and trigger the vehicle-based transceiver to transmit a challenge signal or random number to the portable transponder. The portable transponder typically utilizes an encryption key for encrypting the random number and producing a challenge response signal for transmission to the vehicle-based transceiver.  
      While the portable transponder processes the challenge signal, the vehicle-based transceiver typically utilizes an encryption key for encrypting the same random number, and producing an expected response. In this way, the vehicle-based transceiver typically receives the challenge response signal from the portable transponder and compares the challenge response signal to the expected response. If the challenge response signal matches the expected response, then the vehicle-based transceiver typically actuates a locking mechanism for unlocking the vehicle door.  
      It would therefore be desirable to provide a door handle switch assembly having a simple robust construction for ease of manufacture, efficient installation, low power consumption, and substantially low costs associated therewith.  
     SUMMARY OF INVENTION  
      In one advantageous embodiment of the claimed invention, a mechanical handle switch assembly (“switch assembly”) is provided for actuating a vehicle-based system. The switch assembly includes a door handle, which is coupled to a vehicle door. This door handle is movable a predetermined travel distance, which includes a switch-triggering distance for actuating the vehicle-based system and an unlatching distance for unlatching the vehicle door. The door handle is coupled to a drive train mechanism and utilized for actuating the drive train mechanism. The drive train mechanism is operatively coupled to a switch device for selectively closing the switch device and actuating the vehicle-based system.  
      One advantage of the present invention is that a switch assembly is provided that can detect actuation of a door handle within a substantially short period of time so as to trigger a vehicle-based system and provide the vehicle-based system with sufficient processing time for performing an action.  
      Another advantage of the present invention is that a switch assembly is provided that has a robust construction for substantially decreasing the risk of malfunction.  
      Yet another advantage of the present invention is that a switch assembly is provided that does not require electrical power for detecting actuation of a door handle and therefore is energy efficient.  
      Still another advantage of the present invention is that a mechanical handle switch assembly is provided that has a simple construction for providing ease of manufacture and installation and for decreasing costs associated therewith.  
      Other advantages of the present invention will become apparent when viewed in light of the detailed description of the invention when taken in conjunction with the attached drawings and appended claims. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS  
      For a more complete understanding of this invention, reference should now be made to the embodiments illustrated in greater detail in the accompanying drawings and described below by way of examples of the invention:  
       FIG. 1  is a perspective view of a vehicle having a vehicle based system with a mechanical handle switch assembly (“switch assembly”) integrated within a vehicle door, according to one advantageous embodiment of the claimed invention;  
       FIG. 2  is a side elevation view of the switch assembly shown in  FIG. 1 , as taken along line  2 - 2 , illustrating the switch assembly having a lift configuration and being disposed in a rest position;  
       FIG. 3A  is a side elevation view of the switch assembly shown in  FIG. 1 , as taken along line  2 - 2 , illustrating the switch assembly having a lift configuration and being moved to a switch-triggering position for triggering the vehicle-based system;  
       FIG. 3B  is a side elevation of the switch assembly shown in  FIG. 1 , as taken along line  2 - 2 , illustrating the switch assembly having a lift configuration and being moved to an unlatching position for unlatching the door;  
       FIG. 4  is a top elevation view of the switch assembly shown in  FIG. 1 , as taken along perspective arrow  4 , illustrating the switch assembly having a pull configuration and being disposed in a rest position, according to another embodiment of the claimed invention;  
       FIG. 5A  is a top elevation view of the switch assembly shown in  FIG. 1 , as taken along perspective arrow  4 , illustrating the switch assembly having a pull configuration and being moved to a switch-triggering position for triggering the vehicle-based system, according to another embodiment of the invention;  
       FIG. 5B  is a top elevation view of the switch assembly shown in  FIG. 1 , as taken along perspective arrow  4 , illustrating the switch assembly having a pull configuration and being moved to an unlatching position for unlatching the door, according to another embodiment of the invention;  
       FIG. 6  is a top cutaway view of the switch assembly shown in  FIG. 4 , illustrating the switch assembly having a dampening mechanism with gas compression coupling, according to another advantageous embodiment of the claimed invention; and  
       FIG. 7  is a top cutaway view of the switch assembly shown in  FIG. 4 , illustrating the switch assembly having a dampening mechanism with a viscous fluid coupling, according to yet another advantageous embodiment of the claimed invention. 
    
    
     DETAILED DESCRIPTION  
      In the following figures, the same reference numerals are used to identify the same components in the various views. The illustrated embodiments described herein employ features where the context permits, e.g. when a specific result or advantage of the claimed invention is desired. Specifically, the embodiments described herein utilize a mechanical handle switch assembly (“switch assembly”) for a passive entry system of a vehicle. However, it is contemplated that the switch assembly can be utilized for various other systems and other structures instead of vehicles, e.g. buildings. In other words, a variety of embodiments are contemplated having different combinations of the described features, having features other than those described herein, or lacking one or more of those features. For these reasons, it is understood that the invention can be carried out in various suitable modes.  
      Referring to  FIG. 1 , there is shown a perspective view of a vehicle  10  having a passive entry system  12  with a switch assembly  14 , according to one advantageous embodiment of the claimed invention. The passive entry system  12  further includes a controller  16 , which is coupled to and actuated by the switch device  18 . The controller  16  utilizes a transceiver  20  for transmitting a challenge signal or random number to a portable transponder  22  that is carried by an authorized user. The portable transponder  22  utilizes an encryption key to encrypt the challenge signal so as to produce a challenge response signal for transmission to the transceiver  20 . Likewise, the controller  16  utilizes an encryption key to encrypt the challenge signal and produce an expected response. The controller  16  determines whether the challenge response signal matches the expected response. If the challenge response signal matches the expected response, then the controller  16  actuates a locking mechanism  24  to unlock the vehicle door  26  and allow the door handle  28  to unlatch the vehicle door from its closed position. However, if the challenge response signal does not match the expected response, then the locking mechanism  24  maintains the vehicle door  26  in a latched and locked state.  
      It will be appreciated that the passive entry system  12  requires a minimum processing time period for performing the aforementioned steps and authorizing a person to access the interior of vehicle. As detailed in the description for  FIGS. 2-5B , the switch assembly  14  is utilized for providing the passive entry system  12  with sufficient processing time to unlock the vehicle door  26  before the person moves the door handle  28  to the unlatched position.  
      Referring now to  FIGS. 2-3B , there are shown side elevation views of the switch assembly  14  shown in  FIG. 1 , illustrating a sequence of operating the switch assembly  14 .  FIG. 2  illustrates the switch assembly  14  in a rest position. Additionally,  FIGS. 3A and 3B  show the switch assembly  14  being moved respectively to a switch-triggering position for actuating the vehicle-based system  30  and an unlatching position for unlatching the vehicle door  26 .  
      The switch assembly  14  includes a door handle  28  coupled to a vehicle door  26 . In this embodiment, the door handle  28  has a lift configuration for being pivoted upward. However, as detailed in the description for  FIGS. 4A-5B , the door handle  28  can have various other suitable configurations, e.g. a pull configuration for being pulled outboard from the vehicle door  26 . Referring to  FIG. 3 , the door handle  28  is biased to a latched position via a biasing member  32 . This biasing member  32  is a torsional spring. However, it is understood that the biasing member  32  can instead be a variety of other suitable biasing members as desired.  
      The door handle  28  is coupled to a drive train mechanism  34  for actuating the drive train mechanism  34  when a user moves the door handle  28 . Furthermore, the drive train mechanism  34  is coupled to a normally open switch device  18  for contacting and closing the switch device  18  when the drive train mechanism  34  is actuated by the door handle  28 . Moreover, this switch device  18  is coupled to the passive entry system  12  for triggering the passive entry system  12  when the switch device  18  is closed. In this way, it will be appreciated that operating the door handle  28  triggers the switch device  18  and actuates the passive entry system  12 . One skilled in the art will understand that this simple construction is beneficial for providing ease of manufacture and installation within a vehicle door, as well as minimizing costs associated therewith. In addition, the robust construction substantially decreases the risk of malfunction and does not require an electrical source of power for detecting handle operation by a user.  
      In the embodiment shown in  FIGS. 2-3B , the drive train mechanism  34  is comprised of a first gear member  36  coupled to the door handle  28 , a second gear member  38  operatively coupled to the first gear member  36 , and a cam member  40  integrated within the second gear member  38 . However, as exemplified in  FIGS. 4A-5B , it will be appreciated that the drive train  42  can have various other suitable constructions as desired.  
      As best shown in  FIG. 3A , the gear ratio between the first gear member  36  and the second gear member  38  is sufficiently high for triggering the switch device  18  with substantially little movement of the door handle  28 . Specifically, the door handle  28  is movable a predetermined travel distance, which includes a switch triggering distance (shown in  FIG. 3A ) and an unlatching distance (shown in  FIG. 3B ). Moving the door handle  28  by the switch-triggering distance closes the switch device  18  and triggers the passive entry system  12 . Moreover, moving the door handle  28  by the unlatching distance causes the door  26  to be unlatched and swung open. In this embodiment, the unlatching distance is substantially greater than the switch-triggering distance. One skilled in the art will understand that this feature provides a substantially high amount of time from the moment from when the switch device  18  is triggered to the moment when the vehicle door  26  is unlatched. This feature is beneficial for providing the passive entry system  12  with sufficient processing time for verifying the authorization of the user and actuating the locking device  44  to unlock the vehicle door  26  before the user moves the door handle  28  to the unlatching position.  
      Referring now to  FIGS. 4-5B , there is shown the switch assembly  14 , according to another embodiment of the claimed invention. As mentioned hereinabove, this switch assembly  14  includes a door handle  28  with a pull configuration where the handle is movable in a substantially outboard direction of the vehicle. In addition, the drive train mechanism  34  is a lever arm  46  having a force arm portion  48  coupled to the door handle  28 , a resistance arm portion  52  operatively coupled to a normally closed switch device  18 , and a fulcrum portion  52  disposed between the force arm portion  48  and the resistance arm portion  52 . One skilled in the art will understand that in the rest position (as shown in  FIG. 4 ) a biasing member  32  actuates the lever  46  to contact the switch device  18  and open the normally-closed switch device. Moreover, actuation of the door handle  28  moves the lever  46  away from the switch device  18  thereby allowing the normally-closed switch device  18  to close.  
      The force arm portion  48  is substantially shorter than the resistance arm portion  52 . In this way, the lever  46  triggers the switch device  18  with substantially little movement of the door handle  28 . In other words, the switch assembly  14  provides a substantially high amount of time between the moment the switch device  18  is triggered and the moment the vehicle door  26  is unlatched. This feature is beneficial for providing the passive entry system  12  with sufficient processing time for verifying the authorization of the user and actuating the locking device to unlock the vehicle door  26  before the user moves the door handle  28  to the unlatching position.  
      Referring now to  FIG. 6 , there is shown a top view of the switch assembly  14  shown in  FIG. 4 , according to yet another advantageous embodiment of the claimed invention. This switch assembly  14  includes a dampening mechanism  56  coupled to the door handle  28  for decreasing the speed by which the door handle  28  is moved by the user. In this regard, the dampening mechanism  56  further increases the amount of time required to move the handle  28  from the switch-triggering position to the unlatching position. In this regard, the passive entry system  12  has additional processing time for verifying the authorization of the user and actuating the locking mechanism  24  to unlock the door  58  before the user moves the handle  60  to the unlatched position.  
      In the embodiment shown in  FIG. 6 , the dampening mechanism  56  is a gas compression device. However, as exemplified in  FIG. 7 , the dampening mechanism  56  can instead be a viscous fluid coupling or various other suitable dampening mechanisms as desired.  
      In addition, it will be appreciated that the dampening mechanism  56  can be configured to resist movement of the door handle  28  only between the switch-triggering position and the unlatching position.  
      While particular embodiments of the invention have been shown and described, numerous variations and alternate embodiments will occur to those skilled in the art. Accordingly, it is intended that the invention be limited only in terms of the appended claims.