Patent Application
20210355716
The present disclosure relates generally to automotive door latches, and more particularly, to a power door latch assembly equipped with a power release/power reset motor control to regulate energization and de-energization of a power motor.
This section provides background information related to automotive door latches and is not necessarily prior art to the concepts associated with the present disclosure.
A vehicle closure panel, such as a side door for a vehicle passenger compartment, is hinged to swing between open and closed positions and includes a latch assembly mounted to the door. The latch assembly functions in a well-known manner to latch the door when it is closed, lock the door in its closed position, and unlatch and release the door to permit subsequent movement of the door to its open position. As is also well known, the latch assembly is configured to include a latch mechanism for latching the door, a lock mechanism interacting with the latch mechanism for locking the door, and a release mechanism interacting with the lock mechanism for unlocking and unlatching the door. These mechanisms can be manually-operated via an inside and outside door handle and/or power-operated to provide the desired level of standard features. In known latch assemblies, if the latch mechanism is both power and mechanically actuatable, the ability to utilize power and mechanical release and reset mechanisms continuously coexist, such that the user can use either the power or mechanical mechanism at any time to actuate the latch mechanism. Accordingly, the latch mechanism can be unlatched via power or mechanical actuation of the inside and outside doors handle by the user at any time.
During powered actuation of latch mechanism, both during release and reset operations, it is known to regulate the powered movement of a gear(s) driven by the motor via hard stop features and by sensors configured in direct communication with a driven gear. Such hard stop features can be formed integrally with a housing of the latch mechanism, fixed thereto, or to some other latch component. Upon the gear or feature associate therewith, including a lever associated with latch mechanism, coming into direct physical contact with the hard stop feature, the motor is typically signaled and de-energized. During impact of the gear or feature with the hard stop feature, undesirable noise is generated. Further yet, the energization/de-energization of the motor can be facilitated via detection of the position of the driven gear with the sensor. However, upon de-energizing the motor, the driven gear can continue to rotate via inertia, and thus, the position of driven gear relative to the sensor in communication therewith can be other than desired.
Thus, there remains a need to develop alternative arrangements for latch mechanisms for use in vehicular side door latches which regulate the energization and de-energization of a powered motor without generating noise from stop features associated therewith and also that results in accurate, repeatable and reliable positioning of the driven gear and associated latch components.
This section provides a general summary of the disclosure, and is not intended to be a comprehensive and exhaustive listing of all of its features or its full scope.
It is an object of the present disclosure to provide a power latch assembly for motor vehicle closure applications that overcomes at least those drawbacks discussed above associated with known power latch assemblies.
It is another object of the present disclosure to provide a power latch assembly for motor vehicle closure applications that has a motor that is de-energized without need of hard stop features, thereby resulting in reduced noise operation.
It is another object of the present disclosure to provide a power latch assembly for motor vehicle closure applications that results in accurate, repeatable and reliable positioning of a driven gear and associated latch components.
In accordance with the above objects, one aspect of the disclosure provides a power latch assembly for a vehicle door including a ratchet configured for movement between striker capture and striker release positions and being biased toward the striker release position. The power latch assembly includes a pawl configured for movement between a ratchet holding position whereat the pawl maintains the ratchet in the striker capture position and a ratchet releasing position whereat the pawl releases the ratchet to the striker release position. A pawl release lever is configured to selectively move the pawl between the ratchet holding position and the ratchet releasing position. A powered actuator is energizable to control movement of the pawl release lever to move the pawl from the ratchet holding position to the ratchet releasing position, wherein upon the pawl reaching the ratchet releasing position, the powered actuator is automatically de-energized without a hard stop feature.
According to another aspect of the present disclosure, the power latch assembly further includes an activation/deactivation device configured in operable communication with the pawl release lever. The activation/deactivation device is configured to be in an activated state while the pawl release lever is in a home position, whereat the power release actuator can be selectively energized. The activation/deactivation device is configured to be moved to a deactivated state in response to the pawl being moved to the ratchet releasing position, whereat the power release actuator is automatically de-energized, thereby negating the need for a hard stop feature to stop movement of latch components.
According to another aspect of the present disclosure, the power latch assembly further includes a drive gear driven by the power release actuator, with the drive gear being in meshed engagement with a driven gear having a release cam fixed thereto. The release cam is configured to engage a cam driving surface of the pawl release lever to move the pawl release lever between the home position and the pawl release position in response to the driven gear being driven from a driven gear home position by the drive gear. The release cam is configured for lost-motion movement with the pawl release lever after the pawl release lever reaches the pawl release position, thereby, in combination with the power release actuator being de-energized, negating the need for a hard stop feature to stop movement of latch components.
According to another aspect of the present disclosure, the release cam is configured to travel along a first radii of curvature relative to a rotational axis of the driven gear in response to movement of the driven gear. The pawl release lever has a lost-motion cam surface extending from the cam driving surface. The lost-motion cam surface has a second radii of curvature relative to the rotation axis, wherein the first radii of curvature is substantially the same as the second radii of curvature such that the release cam moves relative to the pawl release lever along the lost-motion cam surface.
According to another aspect of the present disclosure, the pawl release lever can remain stationary as the release cam moves along the lost-motion cam surface, thereby preventing the pawl release lever from moving beyond the pawl release position.
According to another aspect of the present disclosure, the activation/deactivation device can remain in the deactivated state when the pawl release lever is in the pawl release position.
According to another aspect of the present disclosure, the pawl release lever can be provided having a lug configured to trigger the activation/deactivation device to change the activation/deactivation device between the activated and deactivated states.
According to another aspect of the present disclosure, the lug can be configured to return into engagement with the activation/deactivation device to move the activation/deactivation device to the activated state as the pawl release lever returns toward the home position.
According to another aspect of the present disclosure, the power latch assembly can further include a magnet fixed to the pawl and a sensor configured in operable communication with the magnet to detect the position of the pawl, such as when the pawl is in the ratchet releasing position. The sensor is configured in operable communication with the power release actuator to automatically reverse the direction of movement of the power release actuator after detecting the pawl being in the ratchet release position to allow the pawl release lever to return to the home position.
According to another aspect of the present disclosure, the driven gear returns to the driven gear home position without use of a hard stop, thereby reducing the potential for the generation of noise.
According to another aspect of the present disclosure, the driven gear returns to the driven gear home position without use of a sensor detecting the position of the driven gear, thereby reducing complexity and cost.
According to another aspect of the present disclosure, the activation/deactivation device can be provided as one of a physically actuatable/deactuatable switch or proximity sensor configured to determine when the pawl release lever is in the home position and the pawl release position, wherein the activation/deactivation device is configured in operable communication with the power release actuator to allow the power release actuator to be energized when the pawl release lever is in the home position and to be automatically de-energized when the pawl release lever is moved to the pawl release position.
According to another aspect of the present disclosure, the activation/deactivation device can be configured in operable communication with the power release actuator via an electric control unit (ECU), wherein the ECU signals the power release actuator to automatically reverse the direction of movement of the power release actuator upon the pawl release lever reaching its pawl release position, thereby allowing the pawl release lever to return to its home position.
According to another aspect of the present disclosure, a sensor can be configured to detect when the pawl is in the ratchet releasing position, wherein the sensor is configured in operable communication with the power release actuator, such as via ECU, to automatically reverse the direction of movement of the power release actuator after detecting the pawl being moved to the ratchet release position, thereby allowing the pawl release lever to return to the home position.
According to another aspect of the present disclosure, a power latch assembly for a vehicle door includes a ratchet configured for movement between a striker capture position and a striker release position and being biased toward the striker release position. A pawl is configured for movement between a ratchet holding position, whereat the pawl maintains the ratchet in the striker capture position, and a ratchet releasing position, whereat the pawl releases the ratchet for movement of the ratchet to the striker release position. A pawl release lever is configured for movement between a home position and a pawl release position to selectively move the pawl from the ratchet holding position to the ratchet releasing position. A power release actuator is configured to move the pawl release lever between the home position and the pawl release position to move the pawl from the ratchet holding position to the ratchet releasing position. A drive gear is driven by the power release actuator, wherein the drive gear is configured in operable driving engagement with a driven gear having a release cam fixed thereto. The release cam is configured to engage a cam driving surface of the pawl release lever to move the pawl release lever between the home position and the pawl release position in response to the driven gear being driven from a driven gear home position by the drive gear. The release cam is configured for lost-motion movement with the pawl release lever after the pawl release lever reaches the pawl release position, thereby preventing unwanted over-travel of the pawl release lever and negating the need for a hard stop feature to stop movement of the pawl beyond the desired ratchet releasing position, which ultimately results in a quiet, reduced noise operation of power latch assembly.
According to another aspect of the present disclosure, a method of constructing a power latch assembly for a vehicle door is provided. The method includes configuring a ratchet for movement between a striker capture position and a striker release position and being biased toward said striker release position. Configuring a pawl for movement between a ratchet holding position, whereat the pawl maintains the ratchet in the striker capture position, and a ratchet releasing position, whereat the pawl releases the ratchet for movement of the ratchet to the striker release position. Configuring a pawl release lever for movement between a home position and a pawl release position to selectively move the pawl from the ratchet holding position to the ratchet releasing position. Configuring a power release actuator to be energized to move the pawl release lever between the home position and the pawl release position to move the pawl from the ratchet holding position to the ratchet releasing position. Configuring the power release actuator to be de-energized when the pawl release lever reaches the pawl release position to stop the pawl at the ratchet releasing position without use of a hard, positive stop.
According to another aspect of the present disclosure, the method can further include configuring an activation/deactivation device in operable communication with the pawl release lever and configuring the activation/deactivation device to allow the power release device to be energized while the pawl release lever is in the home position and to cause the power release device to be de-energized in response to the pawl being moved to the ratchet releasing position.
According to another aspect of the present disclosure, the method can further include providing the activation/deactivation device as a switch having a closed position while the pawl release lever is in the home position, whereat the power release device can be energized, and an open position while the pawl release lever is in the pawl release position, whereat the power release device is de-energized.
According to another aspect of the present disclosure, the method can further include providing the activation/deactivation device as a proximity sensor configured to detect when the pawl release lever is in the home position, whereat the power release device can be energized, and when the pawl release lever is in the pawl release position, whereat the power release device is de-energized.
According to another aspect of the present disclosure, the method can further include configuring an electronic control unit in operable communication with the proximity sensor and the power operated actuator and configuring the ECU to receive a signal from the proximity sensor indicating the pawl release lever is in its pawl release position and to send a signal to the power release actuator to reverse the direction of movement of the power release actuator in response to the pawl release lever being in its pawl release position, thereby allowing the pawl release lever to return to its home position.
According to another aspect of the present disclosure, the method can further include providing a drive gear to be driven by the power release actuator and configuring the drive gear in operable driving engagement with a driven gear having a release cam fixed thereto, and configuring the release cam to engage a cam driving surface of the pawl release lever to move the pawl release lever from the home position to the pawl release position in response to the driven gear being driven by the drive gear, and configuring the release cam for lost-motion movement with the pawl release lever after the pawl release lever reaches the pawl release position and while the driven gear is moving relative to the pawl release lever.
According to another aspect of the present disclosure, a power latch assembly for a vehicle door, including a ratchet configured for movement between a striker capture position and a striker release position and being biased toward the striker release position, a pawl configured for movement between a ratchet holding position, whereat the pawl maintains the ratchet in the striker capture position, and a ratchet releasing position, whereat the pawl releases the ratchet for movement of the ratchet to the striker release position, a power release actuator operably coupled to the pawl to move the pawl from the ratchet holding position to the ratchet releasing position, and an activation/deactivation device configured in operable communication with the power release actuator, the activation/deactivation device being in an activated state while power release actuator is in a reset position, whereat the power release actuator can be selectively energized, the activation/deactivation device being changed from the activated state to a deactivated state in response to the power release actuator shifting from the reset position to a release position, where the pawl is moved to the ratchet releasing position, whereat the power release actuator is automatically de-energized, is provided. In a related aspect, when the power release actuator is automatically de-energized, the power release actuator is not in a stall condition. In a related aspect, when the power release actuator is automatically de-energized, the power release actuator is displaced from a hard stop, or displaced from contact with a hardstop. In a related aspect, when the power release actuator is automatically de-energized, the power release actuator inertia is dissipated before the power release actuator motion is ceased by contact of the power release actuator with a hard stop.
Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.
These and other aspects, features, and advantages of the present disclosure will be readily appreciated, as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:
Corresponding reference numerals are used throughout all of the drawings to indicate corresponding parts.
One or more example embodiments of a latch assembly of the type well-suited for use in motor vehicle closure systems will now be described with reference to the accompany drawings. However, these example embodiments are only provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail, as they will be readily understood by a skilled artisan.
The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed.
When an element or layer is referred to as being “on,” “engaged to,” “connected to,” or “coupled to” another element or layer, it may be directly on, engaged, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to,” “directly connected to,” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.
Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.
Spatially relative terms, such as “inner,” “outer,” “beneath,” “below,” “lower,” “above,” “upper,” “top”, “bottom”, and the like, may be used herein for ease of description to describe one element's or feature's relationship to another element(s) or feature(s) as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the example term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated degrees or at other orientations) and the spatially relative descriptions used herein interpreted accordingly.
Referring initially to
Referring to
Pawl release lever 34 is operatively (directly or indirectly via another component, such as an intermediate or secondary pawl release lever, and shown as directly, by way of example and without limitation) connected to pawl 32 and is movable between a deployed position, also referred to as pawl release position, whereat pawl release lever 34 moves pawl 32 to its ratchet releasing position, and a non-deployed position, also referred to as home position, whereat pawl release lever 34 permits pawl 32 to be in its ratchet holding position. A release lever biasing member 49, such as a suitable spring, can be provided to normally bias pawl release lever 34 toward its home position.
Pawl release lever 34 can be moved to its pawl release position by several components, such as, for example, by power release actuator system 38, by release lever 36. Power release actuator system 38 includes a first motor, also referred to as first actuator or power release motor 50, having an output shaft 52, with a drive gear, also referred to as power release gear, shown as a power release worm gear 54 mounted on output shaft 52, by way of example and without limitation, and a driven gear, also referred to as power release gear 56. Power release worm gear 54 is configured for operable driving engagement with power release gear 56, and can be configured in direct meshed engagement with power release gear 56, if desired. A power release cam, referred to hereafter as cam 58, is connected in fixed relation for conjoint rotation with power release gear 56 and is rotatable between a pawl release range of positions and a pawl non-release range of positions. In
Power release actuator system 38 can be used as part of a conventional passive keyless entry feature. When a person approaches vehicle 14 with electronic key fob 28 (
To facilitate noise reduction of latch assembly 10 during release and reset operations, and to enhance optimal functionality of latch assembly 10, including repeatable, reliable and accurate performance and positioning of components of latch assembly between repeated use, including precisely controlling the position of driven gear 56, which is ultimately responsible for driving pawl release lever 34, which in turn is ultimately responsible for movement of pawl 32 from its ratchet holding position to its ratchet releasing position, an activation/deactivation device having activated and deactivated states, wherein activation/deactivation device can include a sensor or switch 70, by way of example and without limitation, configured to be triggered or moved between a closed position corresponding to the activated state and an open position corresponding to the deactivated state, is configured in operable communication with the pawl release lever 34 to selectively and desirably regulate power supply to the power release actuator 50. By regulating the power supply to power release actuator 50, driven gear 56 is only rotated when desired, with unwanted over-travel or under-travel thereof being minimized or negated. To further facilitate noise reduction and optimal functionality of latch assembly 10, including repeatable, reliable and accurate performance and positioning of components of latch assembly, including precisely controlling the position of driven gear 56, cam 58 and pawl release lever 34 are configured to produce only intended, desired movement of pawl release lever 34, a lost-motion connection mechanism 72 between cam 58 and pawl release lever 34 is provided. The lost-motion connection mechanism 72 limits the range of movement of pawl 32, such that pawl 32 does not move beyond its intended ratchet release position, and thus, a hard stop feature is not needed to stop the travel of pawl 32, thereby eliminating a potential source of noise. Lost-motion connection 72 allows relative movement between cam 58 and pawl release lever 34 upon pawl release lever 34 reaching its pawl release position and pawl 32 reaching its ratchet release position, such that cam 58 can continue to move rotatably to an over-travel position 74, while pawl release lever 34 remains stationary or substantially stationary (meaning pawl release lever 34 does not move nearly to the extent as release cam 58, such that pawl release lever 34 may move about 1 degree for every 10 degrees of movement of release cam 58) upon pawl release lever 34 moving to the pawl release position and bringing pawl 32 to the ratchet release position. As such, pawl release lever 34 and pawl 32 do not require nor benefit from a hard stop feature, thus, eliminating noise that would otherwise result from impact with a hard stop feature.
Lost-motion connection 72 is established via release cam 58 moving out of engagement with cam driving surface 60 and moving along a lost-motion cam surface 78 of pawl release lever 34. Release cam 58 is configured to travel along a constant first radii of curvature r1 relative to a rotational axis A of the driven gear 56 in response to movement of the driven gear 56. Lost-motion cam surface 78 extends from cam driving surface 60 and has a second radii of curvature r2 relative to the rotation axis A. The first radii of curvature r1 along which an outermost surface of release cam 58 travels is the same or substantially the same as the second radii of curvature r2 of lost-motion cam surface 78. Thus, as release cam 58 moves along lost-motion cam surface 78 (
In the embodiment illustrated in
Switch 70 is shown being fixed, such as to a surface 29′ of housing 29, by way of example and without limitation. Switch 70 is positioned relative to pawl release lever 34 so that the switch 70 is maintained in the closed position (activated state) by a lug 76 of pawl release lever 34 being brought into triggering engagement or triggering close proximity with switch 70 while the pawl release lever 34 is in its home position (
To further facilitate operation of latch assembly 10 without need of hard stop features, a magnet 80 as illustrated in
In accordance with another aspect, as shown in
According to another aspect of the present disclosure, the method can further include a step 1350 of configuring an activation/deactivation device in operable communication with the pawl release lever and configuring the activation/deactivation device to allow the power release device to be energized while the pawl release lever is in the home position and to cause the power release device to be de-energized in response to the pawl being moved to the ratchet releasing position.
According to another aspect of the present disclosure, the method can further include a step 1400 of providing the activation/deactivation device as a switch having a closed position while the pawl release lever is in the home position, whereat the power release device can be energized, and an open position while the pawl release lever is in the pawl release position, whereat the power release device is de-energized.
According to another aspect of the present disclosure, the method can further include a step 1450 of providing the activation/deactivation device as a proximity sensor configured to detect when the pawl release lever is in the home position, whereat the power release device can be energized, and when the pawl release lever is in the pawl release position, whereat the power release device is de-energized.
According to another aspect of the present disclosure, the method can further include a step 1500 of configuring an electronic control unit in operable communication with the proximity sensor and the power operated actuator and configuring the ECU to receive a signal from the proximity sensor indicating the pawl release lever is in its pawl release position and to send a signal to the power release actuator to reverse the direction of movement of the power release actuator in response to the pawl release lever being in its pawl release position, thereby allowing the pawl release lever to return to its home position.
According to another aspect of the present disclosure, the method can further include a step 1550 of providing a drive gear to be driven by the power release actuator and configuring the drive gear in operable driving engagement with a driven gear having a release cam fixed thereto, and configuring the release cam to engage a cam driving surface of the pawl release lever to move the pawl release lever from the home position to the pawl release position in response to the driven gear being driven by the drive gear, and configuring the release cam for lost-motion movement with the pawl release lever after the pawl release lever reaches the pawl release position and while the driven gear is moving relative to the pawl release lever.
The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.
This application claims the benefit of U.S. Provisional Application Ser. No. 63/026,691, filed May 18, 2020, which is incorporated herein by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 63026691 | May 2020 | US |
