Patent Publication Number: US-6213524-B1

Title: Rotary link deadbolt locking actuator and method

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to automotive door locks, and in particular is concerned with a deadbolt locking actuator for a power door latch. 
     2. Description of the Related Art 
     Power door lock systems for vehicles are well-known. For additional security, some vehicles utilize a “deadbolt locking system” to prevent unwanted unlocking of a power door latch by moving a manual lock operator. Only when a predetermined signal (e.g., a key inserted and rotated in a key cylinder) is generated in such a system will a deadbolt actuator permit a door latch to be unlocked. 
     SUMMARY OF THE INVENTION 
     The present invention includes a deadbolt locking actuator for an automotive door latch. The deadbolt actuator is used in a locking system to prevent the unlocking of a door latch when a key has not been inserted and rotated in a selected door, e.g., the driver door. The locking system may include deadbolt actuators for all door latches. 
     In a preferred embodiment, a deadbolt locking actuator includes a housing mounting a reversible motor. A worm is fitted on an output shaft of the motor and meshed with a worm gear. A rotary arm is provided outside of the housing and coupled to the worm gear, A pin on the rotary arm is received in an elongated slot of a link connected to a manual locking lever of a door latch. A control circuit operates the drive unit and link between deadbolt and non-deadbolt positions. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a schematic side view of a preferred embodiment of a deadbolt locking actuator coupled to a partially illustrated door latch by a link, wherein an upper portion of the actuator housing has been removed to illustrate a drive unit. 
     FIG. 2 is a top view of the deadbolt locking actuator and door latch of FIG.  1 . 
     FIG. 3 is a schematic side view of the deadbolt locking actuator in a non-deadbolt position and the manual locking lever in an unlocked position. 
     FIG. 4 is a schematic side view of the deadbolt locking actuator in a deadbolt position and the manual locking lever in a locked position. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     A deadbolt locking actuator is indicated generally at  10  in FIGS. 1-4. The actuator  10  is connected to a conventional door latch  12 , which is only partially illustrated in the figures. Examples of suitable conventional door latches are found in U.S. Pat. Nos. 5,054,827, 5,046,769, and 4,969,673, all of which are assigned to the present assignee and hereby incorporated by reference. 
     The door latch  12  includes a manual locking lever  14  which rotates between unlocked and locked positions as described below. The manual locking lever  14  is conventionally coupled to an inside garnish button, lever, or other inside lock operator, none of which are illustrated in the figures. A conventional integral actuator (not illustrated) is combined with the door latch  12  to operate a power lock actuator arm (not illustrated) in a well-known manner. 
     A link  16  is pivotally connected at a first end to the manual locking lever  14 . At the opposite end, the link  16  includes an elongated slot  18 . As described below, the link  16  is rotated by the actuator  10  to move the manual locking lever  14  between unlocked and locked positions. 
     The actuator  10  includes a housing  20  mounting a drive unit powered via an electrical connector (not illustrated) positioned in a neck  21  of the housing  20 . In FIG. 1, an upper portion of the housing  20  has been removed for clarity of illustration. A worm  22  is fitted on an output shaft  24  of a reversible electric motor  26 . The worm  22  is meshed with a worm gear  28  rotatably mounted on a shaft  30 . A rotary arm  32  having an upstanding pin  34  is provided outside of the housing  20  and coupled to the worm gear  28 . When the motor  26  is operated, the rotary arm  32  rotates with the worm gear  28 . The pin  34  is received in the slot  18  of the link  16 . A bracket  36  connects the housing  20  to the door latch  12 . 
     Preferably, the actuator  10  is controlled by an automotive locking circuit  3 a including a switch activated by a key cylinder (not illustrated). In FIG. 3, a schematic illustration of the actuator  10  includes the upper portion of the housing  20  (which was removed in FIG. 1) illustrating a stop  40  mounted on an outer surface of the housing  20 . The stop  40  is positioned to engage the rotary arm  32 . The actuator  10  is shown in a non-deadbolt state in FIG.  3  and the manual locking lever  14  is rotated clockwise from its position of FIG. 1 to an unlatched position. In this state, the manual locking lever  14  is free to move between the locked and unlocked positions. As the lever  14  is moved, the link  16  is permitted to follow since pin  34  travels in slot  18 . 
     To place the actuator  10  in a deadbolt state, an operator inserts and rotates a key in a driver door key cylinder to close a deadbolt switch, thereby energizing a relay module to power an actuator  10  at each door to the deadbolt state. The motor  26  is powered so that the worm  22  on the output shaft  24  turns the worm gear  28  and rotates the rotary arm  32  clockwise to engage the stop  40  as illustrated in FIG.  4 . The manual locking lever  14  is rotated counterclockwise and blocked in the locked position by the position of the link  16 . The lever  14  cannot be moved from this locked position since the pin  34  cannot travel in the slot  18 . 
     When the driver door key is reinserted and rotated, the driver door is mechanically undeadbolted. The deadbolt switch is opened, which signals the relay module to power the other deadbolt actuators  10  out of the deadbolt state. The motor  26  is powered in the opposite direction to rotate the rotary arm  32  counterclockwise back to the nondeadbolt position illustrated in FIG.  3 . The manual locking lever  16  is now free again to move from the locked to unlocked position due to the pin  34  movement in the slot  18 . 
     Although the present invention has been described with reference to a preferred embodiment, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.