Abstract:
A seat tilt mechanism comprising a cam connected to a lever wherein the lever moves horizontally from a first position to a second position to actuate the cam; a latch configured to engage with the at least one detent and disengage with the cam when the lever is in the first position and configured to engage with the cam and disengage with the at least one detent when the lever is in the second position; said detent includes at least two positions which can be selectively engaged by the latch; and a seat rod configured for attachment between a seat frame and the at least one detent such that when the latch is engaged with the selected position, the tilt of the seat is defined.

Description:
BACKGROUND 
     The present disclosure relates to a mechanism used to tilt a seat and more particularly to a horizontal acting mechanism used to tilt a seat in a vehicle. 
     Many vehicle seats are equipped with a seat tilt adjustment that allows a passenger to adjust the incline of the seat. Often these adjustment mechanisms are located under the front of the seat or on the side of the lower seat cushion. One common type of seat tilt mechanism requires the passenger to reach between their legs and squeeze the vertical acting adjustment handle located on the seat bottom in order to actuate the seat tilt mechanism. This can be difficult because the seat tilt mechanism handle is often located just underneath the seat cushion and the weight of the passenger can cause the seat cushion to encroach on the handle making it difficult to squeeze the handle and actuate the mechanism. Moreover, the weight of the passenger can make it difficult to adjust the seat tilt to the desired position as the passenger&#39;s weight must be accounted for when adjusting the tilt. There is a need, therefore, for seat tilt mechanisms that can be easily accessed and actuated by passengers while they are seated. 
     SUMMARY 
     In one aspect, a seat tilt mechanism comprises a cam connected to a horizontally acting lever that moves from a first position to a second position to actuate a cam. The seat tilt mechanism also includes a latch configured to engage with a detent when the lever is in the first position and to disengage with the detent when the lever is in the second position. The detent includes at least two positions that can be selectively engaged by the latch. The seat tilt mechanism also includes a seat rod configured to attach between a seat and the detent such that the tilt of the seat is defined by the selected position of the detent. 
     In another embodiment, a bezel is configured to engage with a seat and receive a lever therethrough wherein the bezel prevents encroachment of the seat into the lever. 
     The above-described features and advantages, as well as others, will become more readily apparent to those of ordinary skill in the art by reference to the following detailed description and accompanying drawings. While it would be desirable to provide a seat tilt mechanism that includes one or more of these advantageous features, the teachings disclosed herein extend to those embodiments which fall within the scope of the appended claims, regardless of whether they accomplish one or more of the above-mentioned advantages. 
    
    
     
       DESCRIPTION OF THE FIGURES 
         FIG. 1  is a perspective view of the seat tilt mechanism in accordance with the disclosure. 
         FIG. 2  is a perspective view of the underside seat tilt mechanism shown in  FIG. 1 . 
         FIG. 3  is a perspective view of the seat tilt mechanism shown in  FIG. 2  with the lever in a second position. 
         FIG. 4  is a perspective view of the seat tilt mechanism shown in  FIG. 2  and  FIG. 3  showing the lever in a first position. 
         FIG. 5  is a perspective view of the bezel portion of the seat tilt mechanism shown in  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION 
     For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and described in the following written specification. It is understood that no limitation to the scope of the invention is thereby intended. It is further understood that the present invention includes any alterations and modifications to the illustrated embodiments and includes further applications of the principles of the invention as would normally occur to one skilled in the art to which this invention pertains. 
     One type of seat tilt mechanism  10  is shown in  FIGS. 1 and 2 . The mechanism includes a base  12  and a seat rod  14 . The seat rod  14  is adapted for attachment to a seat frame (not shown) which is commonly known in the industry. The seat rod can be attached by any suitable type of attachment or coupling so long as the seat rod  14  is coupled such that the seat can tilt with respect to the seat frame in accordance with this disclosure. The seat rod  14  is mounted towards the front of a seat as best shown in  FIG. 1  to aid in the tilting of the seat but other placement or positioning is contemplated by this disclosure. The base  12  is adapted for attachment to the underside of a seat which typically is a metal or plastic seat pan (not shown). The base  12  can be attached with fasteners or any other suitable means of attachment. The mechanism further includes a lever arm  16  attached to a cam  18 . In one embodiment, lever arm  16  actuates horizontally and is in a locked position when the lever arm  16  is moved to one position. In the illustrations, the lever arm  16  is locked as shown in  FIG. 4 , and is unlocked when moved to another position as shown in  FIG. 3 . 
     The mechanism also includes a latch  20  which includes an engagement bar  22  and a hinge  24 . The seat tilt mechanism  10  also includes two detents  26 ,  28  which are spaced apart and connected by a detent arm  30 . Each detent is configured to include a number of slots  32  for receiving the engagement bar  22 . The detent arm  30  is attached to each detent  26 ,  28  to ensure that the slots  32  on each detent  26 ,  28  are aligned in pairs. The engagement bar  22  is then received by the paired slots  32   a ,  32   b ,  32   c  when the mechanism is locked. Other configurations of engagement between the latch  20  and the detents  26 ,  28  are contemplated by this disclosure. 
     In one embodiment, the mechanism includes three pairs of slots that correspond to three tilt positions. Each pair of slots  32   a ,  32   b ,  32   c  is configured to receive the engagement bar  22  as discussed above. It will be appreciated that when the engagement bar  22  is received in pair  32   a , that the seat rod  14  is displaced from the base  12  slightly and therefore the attached seat will be tilted slightly. As the lever arm  16  is actuated and the engagement bar  22  is received in slots  32   b  or  32   c , the seat rod  14  will be displaced a greater distance from the base  12  and therefore the attached seat will be tilted more. It will be appreciated that additional pairs of slots can increase the number of tilt positions and that three pairs of slots are shown here for illustrative purposes only. 
     Referring to  FIG. 2 , in one aspect of the disclosure the latch  20  is biased towards engagement with the slots  32  using biasing springs  36 . The biasing springs  36  can be connected to the base  12  at one end and to the ends of the engagement bar  22  at the opposite end such that the biasing springs  36  are preloaded or extended when the engagement bar  22  is engaged with the slots  32 . It will be appreciated that by preloading the biasing springs  36  while the latch  20  engaged with the slots  32 , the latch  20  is then biased towards engagement with the slots  32 . Other configurations are also contemplated for biasing the latch towards the slots  32 . 
     Referring now to  FIGS. 2 ,  3  and  4 , to actuate the mechanism, the lever arm  16  is moved to the unlocked position ( FIG. 3 ). As the lever arm  16  moves to the unlocked position, the cam  18  is rotated about its axis and contacts the engagement bar  22  of the latch  20 . The engagement bar  22  may include a contact surface  38  configured to ensure contact with cam  18 . As the cam  18  rotates, it pushes the engagement bar  22  away from engagement with the slots  32  by rotating the latch  20  about its hinge  24  (shown in  FIG. 2 ) which extends the biasing springs  36 . While the engagement bar  22  is disengaged from the slots  32 , the passenger is free to adjust the seat tilt to a desired position. In one embodiment, this adjustment can be further enabled by the use of a lifting rod  40 . The lifting rod  40  is configured to attach to the detents  26 ,  28  on the backside as shown in  FIG. 3 . The lifting rod  40  can be welded to the detents  26 ,  28  in grooves  42 ,  44  or can be attached to the detents  26 ,  28  in any other suitable manner. The ends of the lifting rod  40  are secured to the base  12  with lifting springs  46 . The lifting springs  46  are attached to the base  12  in such a manner as to load the springs so that they create a tension on the lifting rod  40 . It can be appreciated that when the latch  20  is disengaged from the slots  32  the detents  26 ,  28  will be biased to rotate around the axis of the detent arm  30  because of the force created by the lifting rod  40  as applied to the backside of the detents  26 ,  28 . It will be appreciated that a brake  48  ( FIG. 4 ) can be included on the backside of one or more of the detents  26 ,  28  to prohibit rotation of the detents  26 ,  28  beyond a range of desirable seat tilt positions. It will further be appreciated that the lifting rod  40  and lifting springs  46  are not necessary for the positioning of the seat tilt mechanism but provide a means of biasing the mechanism which can make it easier to position when there is weight on the seat. 
     As shown in  FIG. 4  after the desired tilt position has been selected, the lever arm  16  can be moved to the locked position, which will cause the cam  18  to rotate away from the engagement bar  22 . With the cam  18  no longer pushing on the engagement bar  22 , the tension from the biasing springs  36  will keep the engagement bar  22  positioned within the desired pair of slots  32 . 
     Referring to  FIG. 5 , in one embodiment, a bezel  50  is connected to the base  12  such that lever arm  16  extends through an opening  52  in the bezel  50 . The bezel  50  further includes a flange  54  that is configured to engage a seat or seat cushion. It can be appreciated that the flange  54  prevents the seat or seat cushion from encroaching on the lever arm  16  during actuation. 
     Although the present disclosure relates to a seat tilt mechanism, the features disclosed herein may be incorporated into other types of seat positioning devices. 
     The foregoing detailed description of one or more embodiments of the seat tilt mechanism with a horizontal actuation has been presented herein by way of example and not limitation. It will be recognized that there are advantages to certain individual features and functions described herein. Moreover, it will be recognized that various alternatives, modifications, variations or improvements of the above-disclosed embodiments and other features and functions, or alternatives thereof, may be desirably combined into many other different embodiments, systems or applications. Presently unforeseen or unanticipated alternatives, modifications, variations or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the appended claims.