The present invention generally relates to door latches for motor vehicles, and in particular to a latch having an inertial lock feature that locks the latch in the event of a side impact.
In a typical motor vehicle, a door latch is mounted to a vehicle door. The door latch includes a fork-bolt that engages or grasps a striker mounted on the vehicle body structure. A latch release mechanism includes a releasable pawl member that selectively engages the fork-bolt/latch to prevent disengagement of the fork-bolt from the striker. An exterior handle is mounted on an outer side of the door, and an interior handle is mounted on an inner side of the door. The exterior and interior handles are connected to the latch mechanism utilizing a rod, Bowden cable, interfacing cam surfaces, or other suitable mechanical linkage. The purpose of the door handles is to transfer motion and force from the vehicle operator to the latch release mechanism (e.g. pawl) within the latch to release the fork-bolt/latch from the striker. Once the fork-bolt/latch is released from the striker, the door is free to open.
Vehicle door latch mechanisms typically include a locking mechanism that may be within the latch mechanism. The purpose of the locking mechanism is to mechanically couple or de-couple the handles from the pawl.
When an automobile door latch mechanism is in an unlocked state, the exterior handle is connected to the pawl. When the exterior handle is operated (i.e. manually moved by a user), the pawl is operated, and the fork-bolt/latch releases from the striker, allowing the door to be opened. When the automobile door latch is in the unlocked state, the interior release (typically a movable handle or lever) is mechanically connected to the latch release mechanism. Thus, when the interior handle is operated (moved), the fork-bolt/latch will release from the striker.
When a vehicle door latch mechanism is in the locked state, the exterior handle is mechanically disconnected from the latch release mechanism. When the exterior handle is operated, no motion is transferred to the pawl, and the fork-bolt/latch will not release from the striker. Depending upon the requirements for a particular vehicle, the interior handle may be connected or disconnected from the latch release mechanism when the latch is in the locked stated. Thus, movement of the interior handle will release the fork-bolt/latch from the striker in some vehicles even though the door latch is in a locked state. However, in other vehicles, the interior handle is disconnected when the door latch is in a locked state such that actuation/movement of the interior handle does not cause the fork-bolt/latch to release from the striker.
Vehicle door latch mechanisms can be locked/unlocked in various ways. For example, the vehicle door may include a key cylinder on an exterior of the vehicle that is mechanically connected to the locking mechanism within the latch such that rotation of the key cylinder locks/unlocks the locking mechanism. Vehicle doors may include a moveable lock member such as a lever on an interior side of the door that is mechanically connected to the locking mechanism within the latch. Movement of the interior lock member causes the locking mechanism within the latch to lock/unlock. Vehicles may include an interior and/or exterior power lock control, whereby an electrical or pneumatic actuator operates the lock mechanism inside the latch to thereby lock/unlock the lock mechanism. Powered door locks may be actuated by buttons or the like inside a vehicle, or by a remote fob.
A known type of vehicle door latch mechanism includes a lever internal to the latch that connects (unlock state) or disconnects (lock state) the exterior door handle from the latch release mechanism/pawl. The internal lock lever is directly or indirectly connected to an over-center spring such that the lock lever resides in either the lock or unlock state/position. The lock lever can be moved between the locked and unlocked state/position by operation of a key cylinder on an exterior of the vehicle, operation of a mechanical interior lock member, and/or operating an interior or exterior power lock control button or switch. In known door latch mechanisms, the lock lever only moves between the locked and unlocked positions/states in response to a user input or “request” to change the lock state/position of the lock lever. The user request may comprise actuation of a mechanical lock member, power lock control button/switch inside the vehicle, or actuation of a wireless fob. In this type of door latch system, the lock lever does not normally change state (lock or unlock), if the vehicle is subject to a side impact causing a transverse acceleration to the side.
One aspect of the present invention is a vehicle door including a door structure having inner and outer sides. The vehicle door includes a latch mechanism including a latch member or fork-bolt that is moveably mounted to the door structure. The fork-bolt is configured to engage a striker on a vehicle structure to retain the vehicle door in a closed position when the fork-bolt is in a latched position. The fork-bolt is moveable to an unlatched position in which the fork-bolt can be disengaged from a striker to permit the vehicle door to be opened. The latch mechanism includes a latch release mechanism such as a pawl that moves between engaged and released positions. The pawl prevents movement of the fork-bolt from its latched position to its unlatched position when the pawl is in its engaged position. The pawl permits movement of the fork-bolt from its latched position to its unlatched position when the pawl is in its released position. The vehicle door includes an outside door handle that is moveably mounted to the outer side of the door structure. The vehicle door includes an outside release lever that is moveable from a rest position to a released position. The outside release lever is operably connected to the outside door handle by a flexible cable, linkage, or the like. Movement of the outside door handle causes the outside release lever to move from its rest position to its released position. The vehicle door includes an inside door handle or release member that is moveably mounted to the door structure. The door further includes a moveable pawl operating lever assembly that is configured to engage the pawl and move the pawl from its engaged position to its released position. An outside intermediate linkage defines a first configuration wherein the outside intermediate linkage interconnects the pawl operating lever assembly to the outside release lever such that movement of the outside release lever causes the pawl operating lever assembly to engage the pawl and move the pawl from its engaged position to its released position. The outside intermediate linkage defines a second configuration wherein movement of the outside release lever does not cause the pawl operating lever assembly to engage the pawl. The latch mechanism includes a lock lever that rotates between an unlocked position and a locked position about an axis. The lock lever causes the outside intermediate linkage to shift from the first configuration to the second configuration upon movement of the lock lever from the unlocked position to the locked position. The lock lever defines a center of mass that is spaced apart from the axis such that acceleration from a side impact causes the lock lever to rotate from the unlocked position to the locked position. When the lock lever is in the locked position, movement of the outside door handle does not cause the pawl to move from its engaged position to its released position.
Another aspect of the present assembly is a latch assembly for vehicle doors. The latch assembly includes a fork-bolt that is moveable between an engaged position and a disengaged position. The fork-bolt is configured to engage (grasp) a striker on a vehicle body structure when the fork-bolt is in the engaged position to retain a vehicle door in a closed position. The latch assembly includes a latch release mechanism having a pawl member that prevents movement of the fork-bolt from the engaged position to the disengaged position when the pawl member engages the fork-bolt. The latch assembly also includes a moveable pawl operating lever assembly that selectively engages the pawl member and disengages the pawl member from the fork-bolt to permit movement of the fork-bolt from its engaged position to its disengaged position. The latch assembly further includes an outside release member, and an internal lock member that rotates about an axis between locked and unlocked positions. Movement of the outside release member causes the pawl operating lever assembly to engage the pawl member and disengage the pawl member from the fork-bolt when the internal lock member is in the unlocked position. When the internal lock member is in the locked position, movement of the outside release member does not cause the pawl operating lever assembly to engage the pawl member such that the fork-bolt remains in the engaged position. The internal lock member defines a center of mass that is offset from the axis about which the internal lock member rotates such that a transverse acceleration due to a side impact on a vehicle door to which the latch assembly is installed causes the internal lock member to rotate from its unlocked position to its locked position. Thus, movement of the outside release member due to the impact does not cause the pawl member to disengage from the fork-bolt.
These and other aspects, objects, and features of the present invention will be understood and appreciated by those skilled in the art upon studying the following specification, claims, and appended drawings.
In the drawings:
For purposes of description herein, the terms “upper,” “lower,” “right,” “left,” “rear,” “front,” “vertical,” “horizontal,” and derivatives thereof shall relate to the invention as oriented in
With reference to
The door 5 includes an exterior door handle 8 that is movably mounted to a door structure 7 for movement between a rest position and an open position. In
Exterior door handle 8 is operably connected to a door latch mechanism 10 by linkage 12 such that movement of exterior door handle 8 from the closed position to the actuated position unlatches the door latch mechanism 10, unless the door latch mechanism 10 is in a locked state. When the door latch mechanism 10 is in a locked state, movement of the exterior door handle 8 does not unlatch the door latch mechanism 10. As discussed in more detail below, door latch mechanism 10 includes a latch member or fork-bolt 14 (
The vehicle door 5 also includes an interior door handle 18 on an inner side of the door 5. The interior door handle 18 may comprise a lever 20 or other suitable moveable member that is connected to the door latch mechanism 10 by a second linkage 22. Second linkage 22 may comprise mechanical links, cables, or the like. Movement of the lever 20 shifts the second linkage 22 to thereby unlatch the door latch mechanism 10 to thereby permit the vehicle door 5 to be opened. Door 5 may also include a lock cylinder 24 that is connected to the door latch mechanism 10 by linkage 26 to lock/unlock the door latch mechanism 10. Door 5 may also include an interior unlock feature 28 disposed on an interior side of the door. The interior unlock feature 28 can be actuated by a user from inside the vehicle 1 to unlock the door latch mechanism 10. Unlock feature 28 may comprise a push button or switch that is operably connected to a powered actuator 32 by an electrical line 30 to thereby provide powered unlocking of door latch mechanism 10. Alternatively, interior unlock feature 28 may comprise a lever or the like that is mechanically connected to the door latch mechanism 10 by a mechanical linkage of a known type to thereby unlock the door latch mechanism 10 upon actuation of the interior unlock feature 28. A remote fob 34 or the like may also be utilized to actuate the powered actuator 32 to unlock the door latch mechanism 10.
With further reference to
With further reference to
Referring again to
The door latch mechanism 10 also includes an internal lock lever 82 having an opening 84 that rotatably supports the internal lock lever 82 on axle 84 for rotation about the axis A2. As discussed in more detail below, the internal lock lever 82 rotates between locked and unlocked positions to thereby lock and unlock the door latch mechanism 10. Lock lever 82 may be directly or indirectly connected to an over center spring 83 that engages an opening 39 in a cover/housing 37. Over center spring 83 comprises a known spring whereby the internal lock lever 82 is spring-biased for rotation to the unlocked position (
In contrast to known internal lock levers, internal lock lever 82 includes a mass 86 that is offset from the axis of rotation A2. Internal lock lever 82 has a center of mass 87 that is spaced apart from axis A2 such that the internal lock lever 82 rotates from its unlocked position to its locked position when the latch experiences an inward acceleration during a side impact on vehicle 1. It will be understood that a separate mass 86 is not necessarily required to provide a center of mass 87 that is spaced apart from axis A2. For example, internal lock lever 82 may comprise a one piece member that is shaped to provide an offset center of mass 87.
Referring again to
Referring again to
Referring again to
Internal lock lever 82 can be rotated in a clockwise direction from the unlocked position of
As the internal lock lever 82 rotates from the unlocked position of
Rotation of internal lock lever 82 to the locked position of
Referring again to
The mass 86, internal lock lever 82, and other components are preferably configured such that internal lock lever 82 rotates from its unlocked position to its locked position if a horizontal acceleration of at least 20 g occurs. In general, the moment acting on internal lock lever 82 must be sufficient to overcome the over-center spring 83 and other forces tending to keep the internal lock lever 82 in its unlocked position. However, other design criteria (e.g. at least about 10 g or at least about 30 g) may also be utilized as a minimum “lock” acceleration, and the configurations of the components may be designed to meet other such criteria as may be required.
It is to be understood that variations and modifications can be made on the aforementioned structure without departing from the concepts of the present invention, and further it is to be understood that such concepts are intended to be covered by the following claims unless these claims by their language expressly state otherwise. For example, although the axes A1, A2, and A3 preferably extend in a horizontal fore-aft direction, the present invention is not limited to this specific arrangement, and the axes A1, A2, and/or A3 may be oriented in other directions.