Patent Application
20080252129
1. Field of the Invention
The present invention relates to seat fold actuators.
2. Background Art
Actuators and triggers are devices that cause or otherwise induce an apparatus to operate or execute a related function. Latches are devices that are used to grasp or lock an object, as with a catch and a lever, or the like. An actuator may be used to release or engage a latch. Some actuators may be remotely connected to a latch to allow for operation of the latch from a distance.
Latches are used in a wide variety of applications. For example, latches may be provided as a part of a machine, on building doors or windows, or in vehicles. Latches that can be reset have the advantage that they can be used repeatedly. One way to provide a latch that can be reset is to provide an actuator that operates a motor and gear reducer to release the latch by forward rotation of the motor and reset the latch by reverse rotation of the motor. While this approach is effective, the cost of a motor and gear reducer may be uneconomical in many applications.
In some applications, it may be desirable to provide a manual actuator and a power actuator for a latch that may be alternatively used to operate the latch. Dual mode actuators may be provided to allow a latch to be manually operated or power operated. One problem with such dual actuation latches is that one mode of actuation may interfere with the other mode. In addition, resetting the dual mode actuator may be complicated if both modes of actuation are not accommodated by the reset mechanism.
One exemplary application for a dual mode remotely actuated latch is a vehicle seat back folding apparatus. Vehicle seat backs may be folded over the seat base to facilitate ingress and egress. Prior art actuators have been developed that use a motor that drives a gear reducer in one direction to release a latch and driven in the opposite direction to reset the actuator for reuse after the latch is engaged. Seat folding latches may also be specified to be manually actuated in the event that a user wishes to operate the latch manually or if power is not available for the power actuation system. While these types of systems have been developed, the cost of the motor and gear reducer may make such systems uneconomical.
The present invention is pointed out with particularity in the appended claims. However, other features of the present invention will become more apparent and the present invention will be best understood by referring to the following detailed description in conjunction with the accompany drawings in which:
a-7f illustrate the actuator in accordance with one non-limiting aspect of the present invention; and
The vehicle seat 10 may include a seat bottom 12 and seat back 14. The seat back 14 may be positioned relative to the seat bottom 12 to support an occupant. Front and rear floor supports 16-18 may be included to facilitate supporting the seat bottom 12 relative to a vehicle floor or other surface upon which the seat 140 may rest. The front support 16 may include a pivot and spring arrangement 20 or other similar arrangement that allows the seat bottom 12, and thereby, the seat back 14 to automatically rotate about the pivot 20. The rear support 18 may include a releasable floor latch 22 configured to secure the rear portion of the seat bottom 12 to the rear floor support 18 when locked and to permit disengage from the rear support 18 and rotation about the front support 16 when unlocked. These features are shown for exemplary purposes only and the present invention fully contemplates the seat 10 including more or less of these features, depending its configuration and desired operation.
A latch system 40 may be used to restrict rotation of the seat back 14 about the pivot 38, and thereby, rotation of the seat back 14 about the seat bottom 12. The latch system 40 may include a latch 42 operating in cooperation with a cam 44. The cam 44 may be attached to the back bracket 36 and configured to rotate about the pivot 38 when the latch 42 is lowered away from the cam 44 and to be restrained from rotating about the pivot 38 when the latch 42 is engaged with the cam 44. A latch handle 46 may be included and configured to rotate about a latch pivot 48 to control positioning of the latch 42. An rear portion of the handle 46 may be moved in an upward direction to cause the latch 42 to rotate away from the cam 44 and permit rotation of the seat back 14 about the pivot 38. A handle spring 50 may be include to oppose the handle 46 rotation so as to facilitate re-engaging the latches when the seat is folded back from the tumble or fold-flat positions to the upright position.
A cable 52 may be included on the handle 46 to release the floor latch 22 once the rear portion of the handle 46 is rotate upwardly a sufficient distance (see
The seat 10 may further include an actuator 60 to facilitate automatically actuating the handle 46 or other feature of the seat 10 associated with controlling or otherwise facilitating the seat folding operations describe above. The actuator 60, for exemplary purposes only and without intending to limit the scope and contemplation of the present invention, may be configured to actuate the handle 46 between the various positions associated with controlling the seat 10 to actuate from the upright position, to the fold-flat position, and onto the tumble position. The actuator 60 may be configured to rotate the handle 46 to a first position associated with releasing the seat back latch (fold-flat) and then onto a second position associated with releasing the floor latch (tumble). The actuator 60 may operate in cooperation with manual actuation of the seat handle 46 such that seat 10 may be folded with either manual seat handle actuation or automotive actuator provided seat handle actuation.
a-7f illustrate the actuator 60 in accordance with one non-limiting aspect of the present invention. The actuator 60 may include a rod 62 generally configured to move linearly/axially relative to first and second release mechanisms 64-66. One end of the rod 62 may be connected to the seat back bracket 36 or other portion of the seat back 14 and an other end may be free to slide within the second release mechanism 66. The handle release mechanism 66, may be connected to a front portion of the latch handle 46 by way of a handle collar 68.
The rod 62 may move with the trigger release mechanism 64 and the handle release mechanisms 66 may move with the latch handle 46 to facilitate actuating the latch handle 46 and controlling movement of the seat 10 in accordance with the present invention. The first release mechanism 64 may fire to facilitate moving the handle release mechanism in a leftwardly direction to facilitate moving the handle from the A position to the B position, as described below in more detail. The second release mechanism 66 may similarly fire to facilitate moving the mechanism 66 in a rightwardly direction to facilitate moving the handle from the C position to the A position.
The trigger release mechanism 64 may include a reference collar 72, a slide collar 74, and a collar actuator 76, such as but not limited to the type described in U.S. patent application entitled “Rotational Based Actuator Configured to Impart Linear Movement,” filed on Apr. 13, 2007 and assigned Ser. No. ______, the disclosure of which is hereby incorporated in its entirety. The collar actuator 76 may be fired, through electrical stimulation or other control, to slide the slide collar 74 in a rightwardly direction to free a ball bearing 80 from the reference collar 72. As shown, a disk 82 within a housing 84 of the collar actuator 76 slides rightwardly in response to electrical stimulation and as described in the application noted above.
A spring 86 biased between the seat back connected end of the rod 62, upon freeing of the ball bearing 80, slides the trigger release mechanism 64 and a push collar 88 in a leftwardly direction along the rod 62. The push collar 88 contacts the handle release mechanism 66 to move the handle release mechanism 66 leftwardly by a similar distance. The leftward motion of the handle release mechanism 66 moves the handle 46 from the A position (
After the trigger release mechanism 64 is fired and while the rod 62 remains in the upright position or close to it, the trigger release mechanism 64 is moved leftwardly of ball bearing receipt grooves 92 included in the rod 62. This allows the rod 62 to slide with in the trigger and handle release mechanisms 64-66. As the seat back 14 begins to rotate from the upright position, the rod 62 begins to slide within these features and move leftwardly as the seat back 14 rotates until the grooves 92 realign with the ball bearings 80. The realigned ball bearings 80 then drop back into the grooves 92 to re-lock the rod 62 with the trigger release mechanism 64, as shown in
The folded-flat position corresponds with the handle 46 being located in the B position with the seat back latch 46 being disengaged and the floor latch 22 being engaged. The handle 46 must be moved from the B position to the C position in order to disengage the floor latch 22 and allow the seat 10 to continue moving to the tumble position. The spring 86 used to move the handle release mechanism 66 from the A position to the B position may be unable to apply sufficient force to continue moving the handle release mechanism 66 to the C position. The present invention contemplates this and relies on the ball bearings 80 to re-lock with the rod 62 and form the hard-bar linkage such that the seat back 14 in combination with the hard-bar linkage forms a momentum arm having sufficient force to continue moving the handle release mechanism 66 form the B position onto the C position, and thereby, disengage the floor latch 22 and allow the seat 10 to reach the tumble position.
d corresponds with the hard-bar linkage and the seat back momentum causing the rod 62 to continue to move leftwardly to a compressed position where the handle release mechanism 64 is pushed by the push collar 88 to the C position to allow the seat 10 to rotate forwardly to the tumble position. From the tumble position, the seat 10 may then be folded back to the fold-flat or upright positions. In order to return to either one of these positions, the floor latch 22 must be re-engaged, i.e., the handle 46 must be returned to the B position. The handle spring 50 (which for reference is shown in phantom) may provide sufficient force to reset the handle 46 to the A or B positions as the seat back 14 is folded back to those positions.
One problem contemplated by the present invention relates to activation of the collar actuator 76 while attempting to return the seat 10 from the tumble position. Activation of the collar actuator 76 during this time period can result in the first slide collar 74 freeing the first ball bearing 80 such that the spring is free to move the rod 62. This can lead to an imbalanced state. The present invention is able to prevent such an imbalanced state by preventing firing of the collar actuator 76. Turning to
The rightward movement of the handle release mechanism 66 causes a tab 104 on the handle collar 66 to contact a control collar 106 on the collar actuator 76. This causes the control collar 106 to move rightwardly to electrically disconnect the disk 82 used to slide the first slide collar 74. The electrical disconnect of the disk 82 prevents firing of the trigger release mechanism 64, and thereby, the imbalanced state. Once the handle release mechanism 66 is fired, the seat back 14 can continue to be rotated to either one of the fold-flat or upright position. The rod 62 keeps moving rightwardly as the seat back 14 is folded to the upright position until it reaches the upright position, as shown in
As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. The figures are not necessarily to scale, some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for the claims and/or as a representative basis for teaching one skilled in the art to variously employ the present invention.
While embodiments of the invention have been illustrated and described, it is not intended that these embodiments illustrate and describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention.
