Patent Application
20190128019
The present disclosure relates generally to latching systems for compartment closure assemblies of motor vehicles. More specifically, aspects of this disclosure relate to memory levers for single-position latch assemblies of tailgates, liftgates, engine hoods, trunk lids, etc.
Many current production motor vehicles, such as the modern-day automobile, are originally equipped with compartment closure assemblies that are movably mounted to the vehicle body to provide access to the vehicle's various compartments. In automotive applications, driver-side and passenger-side vehicle doors, for example, can be opened and closed to allow user access for entering and exiting the passenger compartment. In contrast, the engine hood (or “bonnet” in some countries) extends over and covers the vehicle's engine compartment to prevent theft or damage of the engine components. A traditional trunk compartment, on the other hand, is a large storage bin located at the rear of the vehicle and covered by a trunk lid that is hinged underneath the passenger compartment's rear deck. By comparison, pickup trucks and other cargo transport vehicles (e.g., sport utility vehicles (SUV), cargo vans, box trucks, etc.) may be typified by a rear cargo compartment that is closed off at the tail end by a hinged liftgate, tailgate, or door assembly. Some automobiles—more commonly referred to as “convertibles”—are equipped with a collapsible roof, while some offer as optional equipment a sunroof panel in the vehicle roof, both of which can be opened for extra sunlight and ventilation for the passenger compartment.
Disclosed herein are memory levers with ajar switch status-retention features for latch mechanisms of vehicle compartment closure assemblies, methods for making and methods for using such latch mechanisms, and motor vehicles equipped with a latch mechanism employing a memory lever for reliably sensing latching and unlatching of a compartment closure assembly. By way of example, there is presented a novel switch memory lever to help accurately indicate a full-unlatched “ajar” status of a single-position latch mechanism. In this latch mechanism, when the striker is disengaged from a forkbolt, a detent lever disengages the forkbolt and engages an ajar switch that responsively outputs an electronic signal indicating an ajar state of the latch. The memory lever engages with the detent to hold the detent lifted when the forkbolt is disengaged from the striker. This memory lever, which is spring-biased against the detent and deactivated off of the forkbolt, has a catch feature that engages a projection of the detent at a position between latch release and full engagement, but within the zone of switch activation. When the forkbolt moves away from the full-latch position, the memory lever engages the detent to hold it lifted in the absence of support from the forkbolt. As the forkbolt returns to the full-latched position, it temporarily lifts the detent off of the memory lever—holding the detent in engagement with the ajar switch—while moving the memory lever out of position, allowing the detent to drop into locking engagement with the forkbolt.
Attendant benefits for at least some of the disclosed concepts include compartment closure latch mechanisms that provide robust ajar switch sensing yet require reduced packaging space over available counterparts. Disclosed latch designs offer more reliable latch status information, especially for multi-latch tailgate and liftgate systems, helping to reduce or otherwise eliminate false-positive “ajar” status warnings. For multi-function tailgates and liftgates, disclosed latch assemblies maintain a reduced footprint which, in turn, offers greater freedom to incorporate larger lamp assemblies without unnecessarily increasing vehicle width or compromising gate opening.
Aspects of the present disclosure are directed to memory levers with ajar switch status-retention features for latch mechanisms of vehicle compartment closure assemblies. For instance, there is presented a latch mechanism for a compartment closure assembly of a motor vehicle. This compartment closure assembly, which may be in the nature of an engine hood, trunk lid, liftgate, tailgate, driver-side or passenger-side door, etc., is movably mounted to the vehicle body to transition back-and-forth between open and closed positions. The latch mechanism includes a forkbolt that attaches, directly or indirectly, to the vehicle body, and moves back-and-forth between latched and unlatched positions. When in the latched position, the forkbolt engages a striker and thereby latches the compartment closure assembly in the closed position. In contrast, when moved to the unlatched position, the forkbolt disengages the striker such that the closure assembly is movable to the open position.
The latch mechanism of this example also includes a detent lever that attaches, directly or indirectly, to the vehicle body adjacent the forkbolt. This detent lever selectively moves back-and-forth between a locked position, whereat the detent lever engages and locks the forkbolt in the latched position, and an unlocked position, whereat the detent lever disengages and releases the forkbolt. A memory lever attaches, directly or indirectly, to the vehicle body adjacent the forkbolt to selectively move back-and-forth between catching and releasing positions. When moved to the catching position, the memory lever engages and retains the detent lever in the unlocked position. Conversely, when moved to the releasing position, the memory lever disengages and frees the detent lever. The forkbolt, when moving from the unlatched position to the latched position, disengages the detent lever from the memory lever and concurrently moves the memory lever from the catching to the releasing position.
Other aspects of the present disclosure are directed to motor vehicles equipped with a latch and lock system for latching closed and governing the opening of a compartment closure assembly. As used herein, the term “motor vehicle” may include any relevant vehicle platform, such as passenger vehicles (internal combustion engine, hybrid electric, full electric, fuel cell, fuel cell hybrid, fully or partially autonomous, etc.), commercial vehicles, industrial vehicles, tracked vehicles, off-road and all-terrain vehicles (ATV), farm equipment, boats, airplanes, etc. A motor vehicle is presented that includes a vehicle body with a passenger compartment for or aft of an interior compartment (e.g., engine bay, trunk, trailer, etc.). Covering an access opening to this interior compartment is a closure assembly that is pivotably mounted to the vehicle body. This closure assembly is manually and/or automatically movable between an open position, providing access to the interior compartment, and a closed position, obstructing access to the interior compartment. A striker, which may include a striker bolt or a U-shaped striker pin, is supported on a striker plate attached to the vehicle body (e.g., in a tailgate or liftgate application) or to the compartment closure assembly (e.g., in a hood latch application).
Continuing with the above example, the motor vehicle is equipped with a latch mechanism operatively connected to a release mechanism, which is located inside the passenger compartment and selectively actuable to disengage the latch mechanism. This latch mechanism includes a latch housing that is mounted to the vehicle body. A forkbolt is rotatably mounted to the latch housing to selectively transition between a latched position, engaging the striker and thereby latching the closure assembly in the closed position, and an unlatched position, disengaging the striker such that the closure assembly is movable to the open position. A detent lever is rotatably mounted to the latch housing adjacent the forkbolt to transition between a locked position, engaging and locking the forkbolt in the latched position, and an unlocked position, whereat the release mechanism disengages the detent lever from the forkbolt. A memory lever is rotatably mounted to the latch housing adjacent the detent lever to transition between catching and releasing positions. The memory lever, when in the catching position, engages and retains the detent lever in the unlocked position. When moved to the releasing position, the memory lever disengages the detent lever. The forkbolt, when moved to the latched position, disengages the detent lever from the memory lever and concurrently moves the memory lever to the releasing position.
Additional aspects of this disclosure are directed to methods for making and methods for using any of the herein depicted or described vehicle latch assemblies. For instance, a method is presented for assembling a compartment closure latch mechanism of a motor vehicle. The representative method includes, in any order and in any combination with any of the disclosed features and options: attaching a forkbolt to the vehicle body to selectively move between a latched position, whereat the forkbolt engages the striker and thereby latches the compartment closure assembly in the closed position, and an unlatched position, whereat the forkbolt disengages the striker such that the closure assembly is movable to the open position; attaching a detent lever to the vehicle body adjacent the forkbolt to selectively move between a locked position, whereat the detent lever engages and locks the forkbolt in the latched position, and an unlocked position, whereat the detent lever disengages and frees the forkbolt; and, attaching a memory lever to the vehicle body adjacent the forkbolt to move between a catching position, whereat the memory lever engages and catches the detent lever in the unlocked position, and a releasing position, whereat the memory lever disengages the detent lever. The forkbolt, when moving from the unlatched position to the latched position, moves the memory lever from the catching position to the releasing position.
The above summary is not intended to represent every embodiment or every aspect of the present disclosure. Rather, the foregoing summary merely provides an exemplification of some of the novel concepts and features set forth herein. The above features and advantages, and other features and advantages of this disclosure, will be readily apparent from the following detailed description of illustrative embodiments and representative modes for carrying out the present disclosure when taken in connection with the accompanying drawings and the appended claims. Moreover, this disclosure expressly includes any and all combinations and subcombinations of the elements and features presented above and below.
The present disclosure is amenable to various modifications and alternative forms, and some representative embodiments have been shown by way of example in the drawings and will be described in detail herein. It should be understood, however, that the novel aspects of this disclosure are not limited to the particular forms illustrated in the appended drawings. Rather, the disclosure is to cover all modifications, equivalents, combinations, subcombinations, permutations, groupings, and alternatives falling within the scope of this disclosure as defined by the appended claims.
This disclosure is susceptible of embodiment in many different forms. There are shown in the drawings and will herein be described in detail representative embodiments of the disclosure with the understanding that these illustrated examples are provided as an exemplification of the disclosed principles, not limitations of the broad aspects of the disclosure. To that extent, elements and limitations that are described, for example, in the Abstract, Summary, and Detailed Description sections, but not explicitly set forth in the claims, should not be incorporated into the claims, singly or collectively, by implication, inference or otherwise.
For purposes of the present detailed description, unless specifically disclaimed: the singular includes the plural and vice versa; the words “and” and “or” shall be both conjunctive and disjunctive; the word “all” means “any and all”; the word “any” means “any and all”; and the words “including” and “comprising” and “having” mean “including without limitation.” Moreover, words of approximation, such as “about,” “almost,” “substantially,” “approximately,” and the like, may be used herein in the sense of “at, near, or nearly at,” or “within 0-5% of,” or “within acceptable manufacturing tolerances,” or any logical combination thereof, for example. Lastly, directional adjectives and adverbs, such as fore, aft, inboard, outboard, starboard, port, vertical, horizontal, upward, downward, front, back, etc., are with respect to a motor vehicle, such as a forward driving direction of a motor vehicle when the vehicle is operatively oriented on a normal driving surface, for example.
Aspects of the present disclosure provide a memory lever with an ajar switch status-retention feature that holds the detent in a lifted position when the forkbolt disengages the striker pin, which functions to reliably retain activated the ajar switch. As the forkbolt moves towards the latched position, e.g., under the force of a moving striker, the forkbolt pushes the memory lever out of engagement with the detent while driving the detent up slightly to lift it over an edge of an engagement surface of the forkbolt. The detent is thereby allowed to drop into engagement with the forkbolt; when this occurs, the ajar switch output signal changes from open to closed (e.g., switch itself changes from “on” (closed) to “off” (open)). The differential position of the detent between the just-released condition and the full-open condition helps to ensure a seamless interaction between the detent, memory lever, and fork bolt. For example, if the latch mechanism is released, but the compartment closure does not move sufficiently within the release pulse, the detent will be dropped either onto a forkbolt surface or a memory lever surface; in either case, it will be supported in a position that activates the ajar switch. If the detent drops onto the forkbolt first, as the closure is opened, it will drop further onto the retaining notch of the memory lever. Conversely, as the gate is closed, the forkbolt lifts the detent while simultaneously pushing the memory lever out of engagement with the detent. Thus, the detent is prevented from moving into an undesirable position that would give a false latch signal. In addition, the latch mechanism architecture helps to ensure that the memory lever cannot interfere with the ability of the latch to be re-engaged.
Referring now to the drawings, wherein like reference numbers refer to like features throughout the several views, there is shown in
Engine hood assembly 18 of
Presented in the inset view of
Housing cover 28 is constructed to conceal and protect a servo motor and gear components (none of which are visible in the views provided) for selectively disengaging a forkbolt 40 from a striker 15 through cooperative operation between the forkbolt 40, a detent lever 42 and a memory lever 44, as will be described in extensive detail hereinbelow. The aforementioned motor and gear components, as well as an electronic ajar switch 46, are mechanically supported on the lower housing bracket 30. Functional support for the forkbolt 40, detent lever 42 and memory lever 44, as well as a pair of bias members 48 and 50, is provided by the housing cover plate 32. Shifting of the forkbolt 40 may be accomplished by an internal drive architecture comprised of a two-way (“reversible”) electric servomotor that transfers driving power through a gear train (e.g., worm gear engaging a spur gear) to synchronously rotate the detent lever 42. Operation of this motor is accomplished through electronic command signals from a vehicle controller or dedicated control module, which are generated responsive to activation of the release mechanism 24. In so doing, the detent lever 42 disengages from the forkbolt 40, allowing the forkbolt 40 to disengage from a striker pin 17 that is mounted to the hood assembly 18 via a striker plate 19.
With continuing reference to
According to the illustrated architecture, the forkbolt 40 is fabricated with a single-piece, J-shaped forkbolt body 51 (
During operation of the latch mechanism 22, cam surface 49 rotates with the detent body 57 around axis A2 to slidably engage with and actuate the ajar switch 46 as the detent lever 42 is moved from the locked to the unlocked position (e.g., from
Conversely, when the forkbolt 40 rotates from the unlatched to the latched position during transition of the latch mechanism 22 to the full-closed state (e.g., from
Aspects of the present disclosure have been described in detail with reference to the illustrated embodiments; those skilled in the art will recognize, however, that many modifications may be made thereto without departing from the scope of the present disclosure. The present disclosure is not limited to the precise construction and compositions disclosed herein; any and all modifications, changes, and variations apparent from the foregoing descriptions are within the scope of the disclosure as defined by the appended claims. Moreover, the present concepts expressly include any and all combinations and subcombinations of the preceding elements and features.
