Vehicle latch

A latch assembly is provided, the latch assembly having a fork bolt movably secured thereto for movement between a latched position and an unlatched position. A detent lever is also provided. The detent lever is capable of movement between an engaged position and a disengaged position, wherein the detent lever retains the fork bolt in the latched position when the detent lever is in the engaged position. The detent lever has a stop member and a guide member each protruding away from a surface of the detent lever and the stop member is in a spaced relationship with respect to the guide member. The latch assembly also includes an actuator for moving the detent lever from the engaged position to the disengaged position by contacting the guide member while the stop member is positioned so that the actuator will contact the stop member and prevent further movement of the actuator when the fork bolt is in the unlatched position and the detent lever is in the disengaged position.

BACKGROUND

Exemplary embodiments of the present invention relate to door, lift gate, glass window and movable panel latches and, more particularly, to latches for vehicles.

A vehicle frequently includes displaceable panels such as doors, windows, hood, trunk lid, hatch and the like which are affixed for hinged or sliding engagement with a host vehicle body. Cooperating systems of latches and strikers are typically provided to ensure that such panels remain secured in their fully closed position when the same is closed.

A latch typically includes a fork bolt that is pivoted between an unlatched position and a primary latched position when the door is closed to latch the door in the closed position. The fork bolt is typically held in the primary latched position by a detent lever that pivots between an engaged position and a disengaged position. The detent lever holds the fork bolt in the primary latched position when in the engaged position and releases the fork bolt when in the disengaged position so that the door can be opened.

The fork bolt is pivoted to the primary latched position by a striker attached to, for example, an associated doorjamb, lift gate, moveable member such as a window etc., when the same is closed. Once in the primary latched position, the detent lever engages the fork bolt to ensure the assembly remains latched.

Accordingly, it is desirable to provide an automatically operated door latch assembly. More specifically, it is desirable to provide an automatically operated door latch assembly that employs a device or motor to move the detent lever from the engaged position to the disengaged position in order to release the striker from the fork bolt.

SUMMARY OF THE INVENTION

In accordance with an exemplary embodiment of the invention, a latch assembly is provided. The latch assembly has a fork bolt movably secured thereto for movement between a latched position and an unlatched position. A detent lever is also provided. The detent lever is capable of movement between an engaged position and a disengaged position, wherein the detent lever retains the fork bolt in the latched position when the detent lever is in the engaged position. The detent lever has a stop member and a guide member each protruding away from a surface of the detent lever. The stop member is in a spaced relationship with respect to the guide member. The latch assembly also includes an actuator for moving the detent lever from the engaged position to the disengaged position by contacting the guide member while the stop member is positioned so that the actuator will contact the stop member and prevent further movement of the actuator when the fork bolt is in the unlatched position and the detent lever is in the disengaged position.

In accordance with another exemplary embodiment of the present invention, a method of operating a latch assembly is provided, the method comprising: rotating a fork bolt into a latched position from an unlatched position; engaging a detent lever with the fork bolt when the fork bolt is in the latched position; releasing the detent lever from the fork bolt by rotating an actuator until it engages a guide member of the detent lever and moves the detent lever into the a disengaged position with respect to the fork bolt; rotating the fork bolt from the latched position to the unlatched position; and preventing the actuator from contacting the guide member by locating a stop member on the detent lever such that rotation of the actuator in a first direction is limited by the stop member when the detent lever is in the disengaged position.

Additional features and advantages of the various aspects of exemplary embodiments of the present invention will become more readily apparent from the following detailed description in conjunction with the drawings wherein like reference numerals refer to corresponding parts in the several views.

Although the drawings represent varied embodiments and features of the present invention, the drawings are not necessarily to scale and certain features may be exaggerated in order to illustrate and explain exemplary embodiments the present invention. The exemplification set forth herein illustrates several aspects of the invention, in one form, and such exemplification is not to be construed as limiting the scope of the invention in any manner.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Exemplary embodiments of the present invention relate to an apparatus and method for providing a latch assembly. Furthermore, exemplary embodiments are directed to a latch assembly having a fork bolt movably secured thereto for movement between a latched position and an unlatched position. The latch assembly further comprises a detent lever capable of movement between an engaged position and a disengaged position, wherein the detent lever retains the fork bolt in the latched position when the detent lever is in the engaged position. The detent lever has a stop member and a guide member each protruding away from a surface of the detent lever and the stop member is in a spaced relationship with respect to the guide member. The latch assembly also includes an actuator for moving the detent lever from the engaged position to the disengaged position by contacting the guide member. The stop member is positioned so that the actuator will contact the stop member and prevent further movement of the actuator when the fork bolt is in the unlatched position and the detent lever is in the disengaged position.

References made to the following U.S. patents: U.S. Pat. Nos. 5,934,717; 6,076,868; 6,565,132; and 7,192,066 the contents each of which are incorporated herein by reference thereto.

Referring now toFIGS. 1-2Da vehicle compartment latch or latch assembly10in accordance with an exemplary embodiment of the present invention is illustrated. In one embodiment, vehicle compartment latch10comprises a housing or support12that is adapted for fastening to a vehicle proximate to a compartment closure.

A fork bolt16is pivotally or rotationally mounted to support12about a pivot pin that is received within a pivot pin opening18of the fork bolt. Fork bolt16is capable of rotational movement between an open or unlatched position shown inFIG. 1and a closed or latched position shown inFIG. 2, wherein the fork bolt rotates in the direction of arrows20.

Vehicle compartment latch10is attached to a vehicle structure such that fork bolt16is moved between the open position shown inFIG. 1and the closed position shown inFIG. 2when a door, window, lift gate, etc. is opened and closed and fork bolt16engages a striker22(illustrated schematically) that is attached to the door, window, lift gate, etc. Alternatively, the vehicle compartment latch10is secured to the door, window, lift gate, etc. and the striker is secured to the vehicle body at an opening into which the door, window, lift gate, etc. is received. The cooperation of a fork bolt and striker is well known and need not be described in detail.

Vehicle compartment latch10further comprises a detent lever24that pivots on support12about a pivot pin received within a pivot pin opening26in the detent lever. The detent lever cooperates with fork bolt16in a well known manner to retain fork bolt16in the closed position shown inFIG. 2or release the fork bolt16for return to the open position shown inFIG. 1. That is, detent lever24pivots between a closed or engaged detent position shown inFIG. 2and a release or disengaged detent position shown inFIG. 1in the direction of arrows28. In accordance with an exemplary embodiment of the present invention, fork bolt16is spring biased clockwise to the open position shown inFIG. 1or in the direction of arrow20aby a biasing member (e.g., coil spring or other equivalent member) that has one end attached to fork bolt16and the other end attached to the housing or other equivalent location. Alternatively and/or in combination with the spring biasing force, the fork bolt can be rotated into the open position by the pulling of the striker as the enclosure of window is opened.

Similarly, a biasing member or spring will also bias the detent lever in the direction of arrow28A counterclockwise against a face of fork bolt16as shown in the FIGS.

In accordance with exemplary embodiments of the present invention, the fork bolt has a surface30that slides along a complimentary surface32of the detent when the fork bolt rotates from the open position (FIG.1) to the closed position (FIG. 2). Once in the closed position (FIG. 2), a shoulder portion34of the fork bolt engages a shoulder portion36of the detent lever thus engaging the fork bolt and securing it into the closed position when the striker is secured in a receiving opening38of the fork bolt. Once the latch is in the closed position the detent lever is spring biased in the direction of arrow28A and shoulder36engages shoulder34such that the fork bolt cannot rotate into the open position unless the detent lever is moved back to the release or disengaged detent position (e.g., moving shoulder36away from shoulder34allowing the fork bolt to rotate in the direction of arrow20A into the open position.

In order to overcome the biasing force in the direction of arrow28A a motor assembly40is provided. Motor assembly40includes a motor42for driving a worm gear44configured and positioned to drive a gear or actuator46. In accordance with an exemplary embodiment of the present invention, motor42is a unidirectional motor such that activation of the motor causes gear or actuator46to rotate in a single direction namely that of arrow48(e.g., clockwise). Gear46has a protrusion50that makes contact with a stop member52and/or a guide member54each protruding away from a surface of the detent lever. The stop member is in a spaced relationship with respect to the guide member. The stop member and the guide member are positioned such that when the fork bolt is in the open position illustrated inFIG. 1and accordingly the detent lever is in the disengaged position rotation of gear or actuator46in the direction of arrow48will cause protrusion50to contact a top surface56of stop member52. This contact (e.g., protrusion50hitting top surface56) prevents gear or actuator46from further rotation in the direction of arrow48. Accordingly and even if the motor is still energized, gear or actuator46cannot rotate once it has made contact with stop member52.

Once the fork bolt rotates into the closed position illustrated inFIG. 2detent lever24rotates in the direction of arrow28A and shoulder portion36of the detent lever engages a complementary shoulder portion34of the fork bolt retaining the fork bolt in the closed position. In addition and now that the detent lever has rotated in the direction of arrow28A, protrusion50is now located in the gap between stop member52and guide member54. Accordingly, rotation of the gear or actuator in the direction of arrow48will now cause the protrusion to contact the guide member as the gear is rotated in the direction of arrow48. This rotation will cause releasable movement of the latch assembly.

This release movement is illustrated inFIGS. 2A-2Dwherein rotation of the gear in the direction of arrow48will cause the protrusion to contact the guide member (FIG. 2A), overcome the biasing force applied to the detent lever and rotate the detent lever in a direction opposite arrow28A such that shoulder36no longer contacts shoulder34of the fork bolt (FIG. 2B) and the spring biasing force applied to the fork bolt causes the same to rotate into the open position from the closed position (FIGS. 1 and 2D). Furthermore, additional rotation of the gear or actuator in the direction of arrow48causes protrusion50to no longer contact guide member54and the biasing force applied to the detent lever in the direction of arrow28A causes the detent lever to rotate back towards the fork bolt however shoulders (34,36) are no longer aligned and surface32makes contact with surface30(FIG. 1or2D). As illustrated, once the fork bolt is in the open position and the detent lever is biased back such that surface32contacts surface30(disengaged position) stop member32and its top surface are positioned such that further rotation of gear or actuator46in the direction of arrow48will cause protrusion50to contact top surface56. The positioning of stop member52prevents protrusion50from continued rotation in the direction of arrow48and further movement of detent lever in a direction opposite of arrow28A is prevented. In accordance with an exemplary embodiment of the present invention the detent lever and the fork bolt rotate in a similar plane or planes parallel or substantially parallel to each other while gear or actuator46rotates in a different plane, which in one non-limiting exemplary embodiment is perpendicular to the plane in which the fork bolt and the detent lever rotate.

FIG. 3provides an enlarged perspective view of detent lever24. As illustrated, stop member52and guide member54protrude from a surface of the detent lever and a gap is provided therebetween so that protrusion50can rotate therein, when the detent lever is in the engaged position contact of the protrusion with the guide member will rotate the detent lever into the disengaged position. In accordance with an exemplary embodiment of the present invention, the stop member provides a limit of travel for the protrusion of the actuator or gear while also providing a means for limiting the amount of energy impacting the detent lever when the protrusion50is rotated and contact top surface56as will be discussed below. Furthermore, the guide member54provides a means for transferring the rotational force of the actuator or gear to the detent lever in order to overcome the biasing force provided to the detent lever.

Referring now toFIGS. 1,4A and4B, rebounding movement of gear or actuator46is illustrated. During operation and as the gear is rotated in the direction of arrow48, protrusion50will contact the top surface of stop member52if the fork bolt is in the open position and the detent lever is in the disengaged position. Further driving of the gear in the direction of arrow48may be limited by a microswitch62(illustrated schematically) that provides a signal to a controller64of the latch as will be described herein. Microswitch62is positioned to engage a cam surface70of the fork bolt such that rotation of the fork bolt from the closed position to the open position causes microswitch62to be actuated by the cam surface moving away and a signal is sent to the controller that controls the motor42. In other words, during operation and when the motor drives the worm gear, rotates the actuator and protrusion50contacts guide member54the detent lever24is rotated from the engaged position to the disengaged position and fork bolt16rotates from the closed position to the open position, this rotation of the fork bolt causes the cam surface to either engage or no longer engage the microswitch which in turn causes the controller to turn the motor off as further driving of the actuator in the direction of arrow48will cause protrusion50to contact stop member52.

Once the motor is the energized, gear member or actuator46is capable of rebounding back from stop member52in a direction opposite to arrow48wherein protrusion50no longer contacts the top surface of stop member52. Two possible locations of protrusion50are illustrated inFIG. 4A. As illustrated, a range of rotation of actuator or gear member46is shown, one limit of this range of rotation is defined by protrusion50contacting stop member52and the other limit of this range of rotation is defined by protrusion50contacting guide member54. Accordingly and if gear or actuator46rotates in a direction opposite to arrow48wherein protrusion50contacts a top surface72of the guide member thus limiting movement of the gear or actuator. In accordance with an exemplary embodiment of the present invention stop member52and guide member54and protrusion50are configured and positioned such that rotation of the gear member or actuator into the positions illustrated inFIG. 4Awhen detent lever is in the disengaged position, the protrusion50will contact the top surface of either stop member or the guide member.

Referring now toFIG. 4B, detent lever24is illustrated in the engaged position and fork bolt16is illustrated in the closed position such that shoulder portions36and34are engaged. Once again and when the motor is de-energized, gear member or actuator46is capable of rebounding back from its position between the stop member and the guide member wherein protrusion50is no longer positioned between the stop member and the guide member however, this range of movement is limited by the top surface of the guide member and a guide surface78of the guide member. Two possible locations of protrusion50are illustrated inFIG. 4B. As illustrated, a range of rotation of actuator or gear member of46is illustrated wherein one limit of the range of rotation is defined by the top surface72of guide member54and the other limit of the range of rotation is defined by a guide surface78of the guide member. In accordance with an exemplary embodiment of the present invention, stop member52and guide member54and protrusion50are configured and positioned such that rotation of the gear member or actuator into the positions illustrated inFIG. 4Bwhen detent lever is in the engaged position the protrusion50will contact the top surface or guide surface of the guide member. Accordingly and when the motor is energized to drive the actuator or gear in the direction of arrow48protrusion50is free to rotate until it contacts guide surface78and moves the detent lever from the engaged position to the disengaged position.

Referring now toFIG. 4C, yet another feature of an exemplary embodiment of the present invention is illustrated. Here gear or actuator46is illustrated in a position wherein protrusion50has not fully traveled past guide member54and detent lever is in the disengaged position. In order to prevent protrusion50and gear member46from being stuck in this position, a cam surface80is position between guide surface78and top surface72of guide member54. Furthermore, protrusion50is configured to have a “kidney” shape such that a curved exterior surface82will contact cam surface80and the biasing force in a direction of arrow28A will cause gear or actuator46to rotate in the direction of arrow48such that protrusion50is not stuck in the position illustrated inFIG. 4C.

Referring now toFIGS. 5A-5B, alternative exemplary embodiments of the present invention are illustrated. Here a lower surface of the detent lever is illustrated. Since the fork bolt and the detent lever rotate in a similar plane or planes that are parallel to each other while the actuator or gear rotates in a plane that is not parallel to the plane in which the fork bolt and the detent lever rotate (e.g., perpendicular or otherwise), rotational forces of the actuator may be imparted to the detent lever and accordingly stabilizing features may be required. InFIG. 5A, the lower surface of detent lever24further comprises a stabilizing feature90that extends from the bottom surface of detent lever24and is in a facing spaced relationship with respect to a surface92of support12such that during rotational movement of the detent lever24stabilizing feature90does not contact surface92however, if the detent lever is in the disengaged position (e.g., fork bolt in the open position) protrusion50may contact the top surface of stop member52as discussed above. In order to prevent the power driven gear member and protrusion50from continuously forcing the detent lever downward in a direction of arrow94such that detent lever24may be damaged or permanently deflected, stabilizing feature90is positioned such that minimal movement of the detent lever downward in the direction of arrow94will cause the same to contact surface92thus causing the applied forces of protrusion50to be directly applied to support12as opposed to damaging detent lever24.

Referring now toFIG. 5Bthe support is configured to have a protrusion or feature96that protrudes away from surface92of the support. This feature will also provide stabilization or support when protrusion50pushes against detent lever24downward in the direction of arrow94. Accordingly, stabilizing feature90and protrusion96provide a means for providing a load path from protrusion50to support12without adversely affecting the rotational plane upon which detent lever24rotates. It being understood that stabilizing feature90and protrusion96may be used together or alone or with the aforementioned embodiments. Moreover, feature90and protrusion96can be aligned with each other or off set from each other. Alternatively, the latch assembly is constructed without feature90and96.

Referring back now toFIGS. 1 and 2and when the latch assembly is opened, the movement of the gear or actuator is limited by a physical stop located in the detent lever (e.g., the top surface of the stop member). At this position and if the motor of the latch assembly is turned on, the gear or actuator won't be able to move since the protrusion50will contact the top surface of the stop member. When the latch assembly is in the closed position, the detent lever will rotate clockwise (FIG. 2) and the physical stop will move so that it is no longer in a blocking position with respect to the protrusion of the gear and the motor of the latch assembly can now be turned on wherein the gear will rotate and the protrusion will advance until it contacts the guide member thereby moving the detent lever from the engaged position to the disengaged position. This movement of the detent lever releases the fork bolt and the same is now capable of rotating from the closed position to the open position. Once again with the fork bolt in the open position in the detent lever and the disengaged position, the physical stop or stop member of the detent will block further rotation of the gear or actuator.

As used herein, the terms “first,” “second,” and the like, herein do not denote any order, quantity, or importance, but rather are used to distinguish one element from another, and the terms “a” and “an” herein do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item. In addition, it is noted that the terms “bottom” and “top” are used herein, unless otherwise noted, merely for convenience of description, and are not limited to any one position or spatial orientation.

The modifier “about” used in connection with a quantity is inclusive of the stated value and has the meaning dictated by the context (e.g., includes the degree of error associated with measurement of the particular quantity).