Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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VEHICLE EASY ENTRY SEAT LATCHING MECHANISM
.
e invention relates to an adjustable seat assembly
for an automotive vehicle, and more particularly to a novel
latching mechanism for a seat back inertia latch system
providing easy entry of passenger6 to the rear seat area of
the vehicle.
BACKGR3U~D OF THE INVENTION
The U.S. Patent 4,440,44~ to Drouillard et al discloses
a seat position control mechanism with an inboard slave
track and outboard control track arrangement having a pair
o the same track assemblies arranged in vertically stacked
relationship. One of the outboard track assemblies provides
for horizontal adjustment of the seat and the other provides
for movement of the seat to and from an easy entry position.
A contrcl cable arrangement interconnects a tilting seat
ack and latch mechanism for the other outboard track
assembly to release a latch mechanism and permit movement of
the seat to the easy entry position.
SUMMARY OF THE PRESET INVENTION
The seat position control mechanism of this invention
rovides an easy entry vehicle seat arrangement having a
ual acting seat back latch mechanisL incorporating both
orizontal teat cushion track adjustment and resilient
orwardly locked positioning of the seat back to
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an easy entry position. The ceat assembly i8 adjUEted for
easy entry by initially manually pivoting the upright teat
back forwardly toward a tilted and latched position. The
initial forward tilting uove~ent of a teat back self
actuating resilient latch mechanism unlatches the teat
track. Subsequent tilting of the seat back causes the latch
mechani6m to lock the seat back in a forward tilted
poBition. The fieat assembly it thu3 free for horizontal
ovement in a forward direction on the unlQcked track for
asy entry with the seat back held in its forwardly tilted
locked position.
To return the seat assembly to a selected horizontal
osition the operator slides the tilted seat back and teat
cushion assembly rearwardly on the unlocked track. When the
rearward sliding effort on the seat exceeds the seat back
latch spring bias, the seat back unlocks allowing the
operator to return the teat back to its upright position.
The unlocking of the seat back causes the track latching
assembly to relock the track. Thus, by selecting the point
uring the rearward txavel of the seat cushion at which the
seat bacX is returned to its upright position the operator
selects the horizontal location of the seat cushion. With
the seat back in its upright position the operator may also
ye the track control handle to horizontally adjust lo teat
u~hion in a conventional manner.
It is thus a feature of the present invention to
rovide the improved vehicle seat assembly described above
aving a dual self-actuating latch mechanism which permits
easy rear seat entry by an operator pivoting the uprisht
seat back to a forwardly tilted and latched position thereby
initially unlocking the seat cushion track and subsequently
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locking the seat back in a forward tilted mode enablying
the seat to be moved to an easy entry position.
A further object of the prlesent invention iB to provide
an easy entry seat latch mechanism wherein the teat
cushion can only be occupied by a passenger with the seat
cushion horizontal adjustment track latched and the teat
back in itB normal upright position.
It is still another object of the present invention to
allow either an operator standing outside the vehicle or a
rear set passenger to readily control the horizontal
adjustment of the seat cushion by varying the position at
which the operator exerts a force on the forwardly latched
seat back when returning the seat assembly to a selected
horizontal position.
hese and other objects, features and advantages of the
invention will be apparent rom the accompanying drawings
and the detailed description of the preferred embodiment of
the invention.
B EF DESCRIPTION OF THE DRAWINGS
Fig. 1 is a perspective view of an automotive seat
assembly embodying the easy entry seat back latch
arrangements of the invention;
Fig. 2 is a perspective view of the vehicle teat
latching mechanism of Fig. l;
Fig 3 it an enlarged elevational view of the seat back
latch of Fig. 2 shown unlatched and with the seat back in
the normal upright position;
Fig. 3A is a fragmentary view of the seat back latch of
Fig. 3 in its intermediate position;
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at
Pig. 4 iB Yiew six r to Fig 3 with the seat back
latch shown latched and with the seat back tilted forward;
Fig. 5 it a partial perspecitve YieW of the carrier
latch portion of the track latchlng mechanism in itB
unlatched mode,
Fig. 6 i5 a fragmentary end elevational view taken of
substantially on the line 6-6 of Fix 4;
Fig. 7 i6 a partially schematic side elevational view
of the teat assembly of Fig. 1 shown in its normal aft
position with the teat back pivoted forward from its dashed-
line normal position to its latched tilted position;
Fig. 8 is a view similar to Fig. 7 showing the seat
assembly roved forward to its track unlocked easy enter
position;
Fig. 9 is a view similar to Pig. 7 showing the seat
cushion returned to it normal position from its dashed-line
forward position with the seat back maintained in its
latched tilted rode; and
Fig. 10 is a view fiimilar to Fig. 7 showing the seat
assembly in its normal track locked position and the seat
back returned to its unlatched upright rode with the track
relatched.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
_ . _
Referring to Fig. 1 a vehicle seat 10 according to the
invention i5 shown positioned in the front or forward
portion of the passenger compartment of a motor vehicle on
the driver's side. Thus, the near side of the teat assembly
in Fis. 1 is the outboard side of the vehicle. The vehicle
~"~ as to
teat 10 comprises teat cu~hio~ 11 aecured to the Yehicle
floor 12, and a teat back 14.
The seat back 14 includes a frame structure, not shown,
supporting the spring and fabric portions of the Nat. The
seat back frame structure provides a sheet metal Bide hinge
member 16. In Fiy. 2 the hinge member i8 shown with an
upper arm 18 fixed to the teat back 14 and a lower arn 20
fixed to a petal fitting portion 22 of the teat cushion
frame. As seen in Figs. 3 and 4 the lower end of the upper
hinge arm 18 is pinned at 24 to the lower hinge arm 20.
A suitable coiled torsion spring reclining mechanist is
generally indicated in phantom outline at 26 in Fig. 2. An
example of a typical recliner mechanism it shown in U.S.
Patent 4,337,978, and reference Jay be had to that patent
for an explanation thereof. The hinge member 16 may also
include an inertia latch system that permits Eree movement
of the seat back 14 while preventing it forward movement
when a predetermined relative acceleration occurs. As the
inertia latch mechanism forms no part of the present
invention it has been deleted from the drawings for the
purpose of clarity. An example of one type of inertia latch
system suitable for use with the present invention is shown
in U.S. Patent 4,358,155 issued November 9, 198~ to
Osterhold et al.
A similar hinge member (not shown) is provided at the
inboard side of the seat back 14. The hinge arms 18 and 20
coact to mount the seat back 14 for pivotal movement
relative to the seat cushion 11. The seat back pivots about
a generally horizontal axis of the hinge pin 24 between the
upright seating position of Figs. 1, 2 and 3 and the
forwardly tilted and latched position oi Fig. 4.
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Seat 10 iB supported on the vehicle for ~ove~ent to a
plurality of horizontally ad justed positions by a
conventional track mechanism ~8 which includes An upper
track member 30 and a lower track member 32. The seat
cushion 10 i6 connected to the upper C-sectioned track
member 30 and i8 slidable on the owe U-sectioned track
member 32. Track ~e~ber 32 is mounted on the vehicle floor
12 by fore and aft brackets 34 and 35~ respectively. The
upper track 30 has a latch menber 37 pivotally mounted on
the top thereof by means of a vertically extending pivot pin
38 located in latch plate 39 and track member 30. A
manually operable control means in the form of a track lever
40, having a handle portion 42, is fixedly attached to latch
plate offset portion 44 (Fig. 5~ by rivets 45. The latch
offset portion 44 ha6 a locking tab 46 extending laterally
therefrom.
Upon manual rotation of the tracX lever 40 latch member
37 pivots about the pivot pin 38 in a counter clockwise
direction indicated by the arrow 47 in Fig. 2. As a result
the tab 46 is released from one of a series of lock openillgs
48 lanced in side flange 49 of the stationary lower track
member 32. A coil tension fipring 50 has one hooked end 5not
shown) connected to the aft end of the upper track ~e~ber 30
and itB other hooked end 51 connected to latch offset
portion 44. The spring 50 i operative to urge or bias the
lock tab 46 into engagement with one of the lock openings
I.
The latch plate 39 has one end of a pull rod 52
connected thereto by a hook portion 53. one rod S2
extends rearwardly with its aft end 54 connected to the
lower portion of a seat actuating lever 55. The actuating
f s
lever 55 it pivotally connected to the lower Beat arn 20 by
pivot pin 56 for pivotal movement about a transver3e a
AB teen in Fiy. 2 the upper end of the actuating lever 55
has a latch pin 58 extending transversely inboard therefrom
parallel. to the axis of the pivot pin 56.
Fig. shows the upper hinge art 18 with a seat back
latch ~echani6~ generally indicated at 60~ The latch
mechanism 60 compri3e~ a hook :latch plate 62 and a striker
plate 64 mounted in flush relationship. The striker plate
64 i3 fixedly secured to the upper hinge arm 13 by a
fastener 66 and a transverse pivot pin 68. The latch plate
62 i5 supported by pivot pin 68 for pivotal movement thereon
relative to the striker plate 64.
As best seen in Figs. 3, 4 and 6 spring means, in the
for of a wire torsion spring 70, urges the latch plate 62
to its spring biased clockwise rotational position. The
biasing spring 70 has one end 72 hooked on fastener 66 and
its other end formed with an L-shaped bend providing
transverse finger portion 74 engaging an arcuate recess 76
in the latch plate 62.
The striker plate forward end has an obtuse angled
notch defined by contact surfaces 78 and 80 providi.ng a nose
portion 82 with an inclined cay surface 84. The latch plate
~2 iB located inboard of the actuating lever 55 with the cay
surface 84 it oriented rearwardly in fipaced relation to the
latch pin 58. I$ will be observed in Figs. 3 and 6. toe
inclined cam surface 84 engages the latch pin 58 when the
seat back 14 is initially roved forward. Upon the cam
surface 84 engaging the latch pin 58 the actuating lever 55
is rotated counter-clockwise about pin 56 causing the latch
pin 58 .o engage arcuate hook portion 86 of the latch plate
62.
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A8 teen in Fig. 3A the latch plate 62 it rotated
counter-clockwi~e about pin 68 against the force of biasing
spring 70. The camming of the hook portion 86 below the
contact eurface 80 allows the pin 58 to slide into
engagement with the striker plate contact surface 78 as
shown in Fig. 4. The seat back i8 thus latched in a forward
titlted mode by virtue of the apring 70 returning the hook
portion 86 to its biased position. It will be noted that a
top pin 87 is located in latch plate 62 and engages the
striker plate 64, as seen in Fig. 3, to limit the biasing
position of the latch plate.
The initial forward tilting of the seat back results in
counter-clockwise pivotal rotation of the actuating lever
55. As a consequence the pullrod 52 pivots the latch plate
39 and unlatches the upper track member 30 from the lower
track member 32. Thus, the tilting of the seat back allows
the seat 10 to slide forward from its Fig. 7 normal upright
position to its Fig. 8 easy entry position with the seat
back forwardly latched as shown in Fig. 4.
To return the seat 10 to its seat back upright mode the
operator moves the seat back 14 aft causing the teat çushion
and its upper track member 30 to slide rearwardly to a
selected seating position shown in Fig. 9. When the track
sliding effort on the moving seat exceeds the torsion spring
70 biasing force the latch plate 62 rotates counter
clockwise about pivot pin 68 unlocking and releasing latch
pin 58. The unlocking of the seat back releases tension on
the track latch coil spring 50 biasing the track latch
member 37 clockwise to relatch the upper and lower track
members With the seat back 14 returned to its upright
seating mode of Fig. 10 the operator assumes a seated
3~
position. The operator quay lien uRe the track lever
handle 4~ to ad just the teat 10 horizontally far and nt in
a conventional teat ad justing manner.
WHAT IS CLAIMED IS:
