Note: Descriptions are shown in the official language in which they were submitted.
3 1 7 9
- . RO'rATABLE: 51~T FOR AN AVTOMOTIVE VEEIICLE
~3AC~SG}~UND OP THE INV:13NTI ON
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The present invention relates to a rotatable seat
for an automotive vehicle, such as van or micrc~bus and so
forth. More specifically, the invention relates to a
rotating mechanism and locking or latch mechanism in the
rotatable seat.
Recently, rotatable seats to be facilitated on
the automotive vehicle, particularly on van or micro-bus
type vehicle, have been developed. Generally, such
rotatable seat is provided with a rotation or pivot
mechanism and a latch mechanism. The rotation mechanism
comprises a vertical axle rotatably received within a boss
formed on the vehicle floor panel. The latch mechanism
usually provided adjacent the rotation mechanism and
prevents the vertical axle from rotating. -The latch
mechanism has a latch member engageable with the vertical
axle or other appropriate section o the rotation mechanism
so that it may prevent the vertical axle and thus the
- rotatable seat from rotating.
Since the rotational force due to remarkable
inertia caused by collision of the vehicle or abrupt
deceleration is applied to the vehicle not only at the
pivoted portin but also the portion apart from the pivot,
the conventional latch mechanism must be provided an enough
force in order to prevent the seat rom rotating. However,
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due to lacking of space below the seat, there could not be
provided an appropriate mechanism having enough resistance
against the rotational force applied to the portion apart
from the pivot. Furthermore, according to the typical
construction of the conventional rotatable seat, the latch
member is urged to latching position by a spring. This
bias spring provided for the latch member has insufficient
bias force for completely preventing the seat from
accidentally rotating. On the other hand, bet~een the
bottom of the seat and the vehicle floor panel, is provided
not enough clearance for providing with powerful spring for
biasing the latch member to latching position. Assuming it
is possible to provide a spring having enough force to
prevent the seat from accidentally rotating, this may cause
difficulty of releasing from latching position when the
seat is to be rotated.
Preventing the seat from accidentally rotating
may be accompIished by providing the l-atch mechanism at the
portion aparting from the pivot, where greater rotational
~orce with respect to the pivot will be applied. This may
require less biasing force than the latsh mechanism
provided adjacent the pivot. Therefore/ releasing of the
latch mechanism from latching position may require smaller
power to permit ea~y operation of seat rotation when the
seat is to be rotated.
SUMMARY OF THE;IRV~NTION
There~ore, it is an object of the present
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invention to provide a rotatable seat having a lock or
latch mechanism which can e~fectively prevent the rotatable
seat from accidentally rotating and requires less
operatîonal power for releasing the latch mechanism from
5 latching position when rotation of the seat is desired.
To accomplish the above-mentioned and other
objects, there is provided a rotatable seat for an
automotive vehicle which has a rotation mechanism and a
latch mechanism independent of the rotational mechanism.
The rotation mechanism includes means for vertically moving
the seat between a first position in which seat is
prevented from rotating and a second position in which the
seat is permitted to rotate about the vertical axis
thereof. The latch mechanism includes means for providing
latch-and-hook engagement at both the front and the rear of
the seat. The latch-and-hook engagement is releasable from
the engaged condition by operating a manual lever.
According to the present invention, the rotation
mechanism further includes means for ca~sing rotational
movement of the seat at the second position due to the
seat's own weight.
Further, accordlng to another aspect of the
invention, the rotatable seat is further provided with a
holding mechanism to hold the seat at the second position.
The holding mechanism includes means for releasing the seat
from the held position after seat rotation is completed.
According to a further aspect of the invention,
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.the rotatable seat is provided with a saEety mechanism
which prevents inadvertent release of the latch-and-hook
engagement whi.~e passengers are sitting thereon.
According to the invention, as broadly claimed,
there is provided a rotatable seat for an automotive
vehicIe comprising a seat rotatably supported on a vehicle
floor with a rotational pivot which permits the seat to
rotate in the horizontal plane thereabout, a rotation
mechanism for moving the seat between a first position in
which the seat is prevented from rotating and a second
position in which the seat is permitted to rotate.about the
rotational pivot, a latch mechanim for latching the seat.
in a position facing either forward or back with respect to
the vehicle, the latch mechanism having first and second
. latching assemblies provlded at the front and the rear of
the seat,. which first and second latching assemblies being
movable between a third position in which the seat is
prevented from rotating and a fourth position in which the
seat is permitted to rotate about the rotational pivot and
20~ an actuating lever to operate said rotation mechanism to
: ~ move the seat from the first position to second positin and
said:: first and the latching assemblies from the third
. position to the fourth position to permit seat rotation.
BRI~3? D335CRIPTION OF T}~E RA~INGS
: . : 25 The present invention will be understood more
~ ~ fully from the detaiIed description give herebelow and from
:~ . the accompanying drawings of the preferred embodimènts of
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the present invention, which, however, should be taken as
limitative to the invention but for elucidation and
explanation only.
In the drawings:
Fig. 1 is a plane view of a micro-bus type
automotive vehicle having a rotatable seat according to the
present invention;
Fig. 2 is a side elevation of the micro-bus type
automotive vehicle of Fig. l;
Fig. 3 is a sectional view of the first
embodiment of a rotatable seat according to the present
invention;
Fig. 4 is an enlarged sectional view of a
rotational mechanism of the rotatable seat of Fig. 3, which
is taken along line IV-IV of Fig. 3;
Fig. 5 is a perspective view of the rotation
mechanism of the rotatable seat of Fig. 3;
Fig. 6 is a similar view to Fig. 3 but showing
the seat in a position lifted up for rotation;
Fig. 7 is an illustration of the rotation
mechanism which detalls the relative dimensions of a cam
member, supporting roller and lifting roller;
Fig. 8 is a perspective view of the second
embodiment of the rotatable seat according to the present
invention;
Fig. 9 is a sectional view of the rotatable seat
of Fig. 8 showing detail of the construction thereof;
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Fi~. 10 is a perspective view showing the
relationship between the lifting lever and the holding
lever~in the rotatable seat construction of Fig. 9;
Fig. ll is a perspective view showing an
actuating lever of the ro~atable seat of Fig. 9;
Fig. 12 is a side elevation view of the holding
lever showing movement thereof;
Fig. 13 is a side elevation view of the actuating
lever showing operation thereof;
Fig. 14 is a side elevation view of the rotatable
seat according to a modification of the second embodiment
of Fig. 9;
Fig. 15 is a perspective view of the rotatable
seat of Fig. 14;
I5 Fig. 16 is a perspective view of a blocking lever
in the interlock mechanism provided in the rotatable seat
of Fig. 14; and
Fig. 17 is a plan view of the blocking lever
showing operation thereof.
; 20 DESCRIPTION O~ T~ P~EFERRED EMBODIMENT
Referring now to the drawings, particularly to
Flgs. l and 2, there is illustrated a van or micro-bus type
automotive vehicle. In the passenger compartment, three or
more vehicle seats, generally of the bench type, are
installed parallelly with respect to one another. A
rotatable seat 20 is positioned between a driver's seat 22
and a rear seat 24. The rotatable seat 20 is rotatable
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about its vertical axis to alternate the direction in which
the seat faces between forward and backward, as shown in
Figs. 1 and 2. A pair of front and rear legs 26 and 28 are
provided for the rotatable seat 20 and are mounted on a
seat support 30. A rotation mechanism 32 is inter-
positioned between the bottom of the rotatable seat 20 and
the upper surface of ~he seat support 30. The rotation
mechanism 32 permits rotation of the rotatable seat about
its vertical axis for alternating seat direction. A latch
mechanism 34, which is shown in Fig. 3 and is also
interpositioned between the bottom of the rotatable seat
and the upper surface of the seat support, holds the seat
20 in either of two positions in which the rotatable seat
is directed either forward or backward.
Figs. 3 and 4 show the first embodiment of the
rotatable seat strl~cture according to the present invention
and detailed construction of the-rotation mechanism 32 and
latch mechanism 34 o the rotatable seat. Generally, the
rotatable seat comprises a seat cushion 36 and a seat back
38. A seat cushion 36 has a seat support frame 40 at the
bottom thereof. A rotational axle 42 vertically extends
rom the seat support frame 40 at the center of the seat.
The rotational axle 42 is fixed to the seat support frame
40 with fastening means such as fastening bolts 44.
Surrounding the rotational axle 42, an annular cam member
46 is fitted to the center of the seat support frame 40.
~he cam member 46 has cam faces 50 and 52 on the lower edge
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thereof. The cam member 46 is also formed with a pair of
diametrically-opposed rounded c~t outs 54. Two support
rollers 56 are each rotatably supported at one end of a
corresponding shaft 58, the other end of which is secured
to brackets 50 projected from the upper surface of the seat
support 30. The cut outs 54 simultaneously receive the
support rollers 56 when the rotatable seat 20 is latched at
a position facing either forward or backward.
As shown in Fig. 5, liting rollers 62 and -64
abut the lower surfaces 66 of diametrically-opposed
laterally-extending portions 68 of the cam member 46. The
lifting rollers 62 and 64 are rotatable about shafts 70.
The shafts 70 are secured to the ends of lifting levers 72
and 74. The lifting lever 74 is horizontally angled and
has a circular hole 76 at the other end thereof and the
llfting lever 72 is horizontally and vertically angled and
has a circular hole 78 at an intermediate portion thereof.
The holes 76 and 78 of the levers 74 and 72 receive either
end of a rotational a~le 80. The axle 80 is rotatably
supported by brackets 82 projecting from the upper`surface
of the seat support 30, The axle 80 is secured to each of
the holes 76 and 78 so that the levers 72 and 74 rotate with
each other according to rotation of the axle 80.
The lower end of the lifting lever 72 is
connected to a linking lever 84 via a connecting rod 86.
The connecting rod 86 connects the lifting lever 72 to the
linking lever 84 so that the lifting lever 72 and the
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. lifting lever 74 can be rotated about the horizontal
axle 80 thereof in response to rotation of the linking
lever 84. The linking lever 84 is secured to a shaft 86
which is rotatably supported by the seat support 30. A
manually~operable lift-up lever 88 is also secured to the
shaft 86 for rotation with the linking lever 84. The lift-
up lever 88 has at the free end thereof a handle 90 for
comfortable gripping therefor. The lifting lever 72 is, in
turn, biased by a spring 92 in the direction in which the
lifting roller 62 is.moved downwards about the horizontal
- axle 80. One end of the spring 92 is secured to the seat
support 30.
The rotational axle 42 is received through a
cylindrical boss 94 inserted into an bore 96 formed in the
seat support 30. The seat support 30 has a recess 98 at a
position housing the free end of the rotational axle 42. A
pair of bushings 100 and 102 are inserted into opposite
ends of the boss 94. Each of the bushings 100 and 102 has a
flange portion 104 and 106 and a cylindrical portion 108
and 110 respectively which engage with the ends of the
boss. The bushings 100 and 102 serve to pre~ent rotational
friction between the rotational axle 42 and the inner
~ periphery of the boss 94.
: As shown in Fig. 3, the latch mechanism 34
: : 25 generally comprises a pair of hooks 112 and 114 secured to
the seat support frame 40 near the front and rear ends of
: the seat cushion 36, and a pair of latches 116 and 118
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releasably engaged with the hooks. The upper end of each
latch 116 and 118 has a hook portion 121 and 123 which is
engageable with the hook 112 and 114 respectively. The
latches 116 and 118 are respectively secured to shafts 120
and 122 rotatably supported by the seat support 30. A
portion of the latch 116 above the shaft 120 is connected
to a portion of the latch 118 below the shaft 122 via a
connecting rod 124 for co-ordinated movement therewith. A
manually-operable release lever 126 is secured to the shaft
120 in order to rotate the shaft 120 and the latch 116. The
latch 118 is connected to one end of a bias spring 128. Thé
other end of the bias spring l28 is engaged with the seat
support 30 in order to provide a spring force biasing the
latch 118 in the direction in which the hook portion 123
engages with the hook 114. Similar to the lift-up
- lever 88, the release lever 126 has a handle 130 or
comfortable operation thereof.
In operation, when the release lever 126 is
pulled to rotate the shaft 122 clockwise as shown in
Fig. 3, the latch 116 is thus rotated clockwise so that the
hook portion 121 and the hook 112 disengage. At the same
time, the Iatch 118 rotates counterclockwise according to
the rotation of the latch 116 so that the hook portion 123
and the hook 114 disengage. In this position, when the
lift-up lever 88 is pulled to rotate the shaft 86 together
with linking lever 84 clockwise in Fig. 3, the rotation of
the linking lever 84 is transmitted to the lifting lever 72
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to rotate the latter with the other lifting lever 74. Due
to the rotation of the lifting levers 72 and 74, the
lifting rollers 62 and 64 come to contact with the lower
surfaces 66 of the laterally-extending portions 68 of the
cam member 46 to push the seat 20 upwards. The seat 20 is
thus raised. Due to the upward movement o~ the seat 20,
the support rollers 56 are released from the cut outs 54 of
the cam member 46 as shown by the arrows in FigO 7.
Therefore, the seat 20 can horizontally rotate about the
vertical axis of the rotational axle 42. At a position in
` which the seat is slightly rotated, the support rollers 56
come into contact with the cam faces 50, as shown in
; Fig. 7.
At this position, when the release lever lZ6 and
the lift-up lever 88 are released by the user~ they return
~ to their respective initial positions. Although the
- release lever 126 and lift-up lever 88 return to their
respective initial positions, the seat 20 with the cam
member 46 is held in the unlatched and raised position by
the supporting rollers 56. The seat 20 is thus permitted
to rotate about the vertical axis of the rotational axle 42
in order to alternate the seat facing. In this position,
~ the weight of the seat 20 is vertically applied to the
; ~ contact points C between the support rollers 56 and the cam
face 50.- ~ince the cam face 50 is inclined with respect to
the horizontal plane and the force due to gravity is
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applied perpendicular to the cam face, i.e., in the
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direction of moment, there exists a horizontal component of
the reacting moment against gravity, and thus the seat 20
rotates about its vertical rotational axis by itself
without requiring application of an external force. During
rotation of the seat, the support rollers 56 remain in a
:; position abutting the cam faces 50 and 52 so that the seat
20 and the cam member 46 are kept in the raised position.
As the seat 20 approaches the desired forward or
backward position, the support rollers 56 reach the end of
the appropriate cam face 50 or 52 and drop into the cut-
outs 56, i.e., the seat 20 returns to the normal lowered
position. At the same time, the hooks 112 and 114 are
lowered over the ends 121 and 123 of the latchs 116 and
118. As the hooks pass over the hooked ends 121 and 123,
the latches 116 and 118 are displaced slightly from and
then returned to the initial positions thereof, now firmly
engaged with the hooks 112 and 114. Due to the engagement
of the support rollers 56 and the -cut outs 54 and the
engagement of the latches 116 and 118 and the hooks 112 and
114, the seat 20 is prevented from rotating.
The relationship between the support roller 56,
lifting roller 62 and 64, and cam member 46 will be
described in further detail with reference to Fig. 7. In
the initial position, the support rollers 56 are placed
within the cut outs 54 with a clearance dl from the bottom
of the cut out. Also, the lifting rollers 62 and 64 are
placed away from the lower surface 66 of the extending
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portion 68 at a distance d2. These clearances aremaintained in the lowered position by the length of the
front and rear legs 26 and 28. The vertical motion
distance of the lifting roller 6~ and 64 is determined in
correspondence with to the depth d4 of the cut-outs 54 and
in correspondence with the required vertical displacement
of the cam member 46 with respect to the support rollers
56. The circumferential extent of the extending portion 68
is greater than the horizontal displacement distance d5 of
the lifting rollers 62 and 64, caused by operation of the
lifting levers 72 and 74.
In the initial position, the horizontal axis P
of the support rollers 56 is placed at the center of the
circle of the rounded bottom of the cut-outs 54. Each
roller 62, 64 and 56 has diameter rl which is smaller than
that r2 of the rounded bottom of the cut out 54 so that it
may provide clearance dl between the upper end of the
roller 56 and the circumference of the cut-outs 54. This
will aid smooth engagement of the support rollers 56 and
the cut-outs 54 at the end of seat rotation.
Figs. 8 to 13 show the second embodiment of the
rotatable seat according to the present invention. In this
embodiment, the rotation mechanism 32 and latch mechanism
- 34 in the foregoing embodiment are cooperatively combined
so that they can be operated with a single actuating lever.
Further, the present embodiment of the rotatable seat is
provided with a holding mechanism for holding the seat at
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the raised position.
Fig. 9 is a fragmentary perspective view of the
- rotatable seat 140 in which the combined rotation mechanism
142 and latch mechanism 144 with the holding mechanism 146
is illustrated. As can be seen from Fig. 9, the rotational
seat 140 has pivot means similar to that of the foregoing
- embodiment, about which the seat rotates. As shown in
Fig. 10, the pivot means comprises a rotational axle 148
received with a cylindrical boss 150. The boss 150 is
inserted into a through opening formed in a seat support
152. The rotational axle 148 is rotatable about thé
vertical axis of the boss for permitting rotation of the
seat 140. Likewise to the first embodiment, a cam member
154 surrounds the rotational axle 148. A pair of lifting
rollers 156 and 158 are movably provided adjacent the cam
member 154. The li~ting rollers 156 and 158 are rotatably
mounted at one end of lifting levers 160 and 162 so that
the lifting roller lift up the cam member 154 with the
rotatable seat 140 by rotational movement of the lifting
levers 160 and 162.
The lifting lever 160 is connected to an
actuating lever 164 via a connecting rod 166. The
actuating lever 164 is arranged so that it can also release
latches 168 and 170 respectively engageable with hooks 172
and 174. The actuating lever 164 further operates a
holding mechanism 146 which comprises a holding lever 176
pivotable between positions corresponding to latching and
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unlatching in response to the movement of the actuating
lever.
Now, referring to Figs. 10 to 14, the rotation
mechanism 142, the latch mechanism 144 and the holding
mechanism 146 will be described in detail. Similarly to
- the oregoing first embodiment, the cam member 154
encircles the top of the rotational axle 148 and has cam
faces 178 and 180 at the lower end thereof. Also, the cam
member 148 has diametrically-opposed cut-outs 182 with
rounded ends. Support rollers 184 rotatably supported by
shafts 187 at the upper ends of brackets 186 are received
in the cut-outs in the initial position of the seat 140.
The lifting rollers 156 and 158 oppose the lower surface of
extending portions 188 laterally extending from the outer
periphery of the cam member 148 along the underside of the
seat 140. The lifting roller 156 is rotatable about an
axle 192 projecting from one end of the lifting lever 160~
Likewise, the lifting roller 158 is rotatably mounted on an
axle 194 projecting from one end of the lifting 7ever 162.
As shown in Fig. 10, the lifting lever 160 is horizontally
and vertically angled and secured onto one end of a shaft
196 at its vertical corner 198. On the other hand, the
li~ting lever 162 is horizontally angled and secured onto
the other end of the shaf:t 196 at the end opposite the
llfting roller 158. The shaft 196 is rotatably supported
by a pair of brackets 200 projecting from the upper surface
of the seat support 152. A bias spring 199 is connected to
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the lifting lever 160 to that it biases the latter to an
initial position displaced from the cam member 148 as shown
in Fig. 9.
Through a connecting rod 166 and a connecting
lever 204, the lower end of the lifting lever 160 is
connected to a fan-shaped cam lever 206 secured to a
rotatable shaft 208 together with the actuating lever 164.
As particularly shown in Fig. 11, front side edge of the
fan-shaped cam lever 206 opposes a contact pin 210
projecting from a contact lever 212 which is secured to a
rotatable shaft 214, to which, the latch 168 is also
secured. The contact lever 212 is connected with the latch
170 via a connecting rod 216. The latch 170 is biased
toward an initial position, in which the latch 170 engages
with the hook 172 or 174 by a bias spring 217.
The holding lever 176 is pivotably supported by a
: shaft 218. The holding lever 176 is biased upwards by a
sprln~ 220 so that the portion 222 thereof constantly
: ~: contacts with the underside of a pin 224 projecting from
the side surface of the lifting lever 160. Thus~ ~he pin
: 224 limits rotation of the holding lever 176 about the
shaft 2180 A roller 226 is rotatably mounted ~n a shaft
230 at:the top of a portion 228 of the holding lever 176.
The:holding lever 176 has a cut-out 232 at the end of the
portion 222. The cut-out 232 is engageable with the pin
~: 224 a~t the extreme position of rotation of the holding
lever 176. The roller 226 opposes a cam plate 234 with a
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cam face 236 so that it contacts the latter during rotation
of the seat 140.
~ In the initial position where the rotatable seat
140 is directed forward or backward and locked to be
prevented from rotating, the latches 168 and 170 engage the
hooks 172 and 174 to maintain the seat 140 in the latched
position~ At this position, the support rollers 184 are
disposed within the cut-outs 182 to prevent the seat from
rotating in cooperation with the latch-and-hook
engagement. The pin 224 of the lifting lever 160 pushes
the holding le~ver downwardly against the spring force of
the spring 220 in order to displace the roller 226 from the
cam face 236 of the cam plate 234. Also, the lifting
rollers 156 and 158 are disposed in an initial position
displaced from the lower surface of the extending portions
188 and 190 at a distance dl. In this position, front and
rear legs 238 and 240 extending from the bo~tom of the
rotatable seat 140 rest on the upper surface of the seat
support 152.
In operation, when the actuating lever 164 is
rotated about its rotation axis in the clockwise direction,
the cam lever 206 coaxially secured to the shaft 208 is
thus rotated clockwise to force the pin 210 of the contact
~ lever 212 clockwise. By rotation of the contact lever 212
about the axis thereof, the latch 168 is rotated clockwise
to disengage from the hook 172. Corresponding to the
rotation of the contact lever 212, the latch 170 rotates
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counterclockwise to disengage from the hook 174.
According to the rotation of the actuating lever
164, the cam lever 206 rotates clockwise in Figs. 9 and 12.
The rotational force of the cam lever 206 is transmitted to
the lifting lever 160 via the connecting lever 204 and the
connecting rod 166. The lifting lever 160 is thus rotated
- with the lifting lever 162 to bring the lifting rollers 156
and 158 into contact with the lower surfaces of the
extending portions 188 and 190 to raise the seat 140.
During lifting lever rotation, holding lever 176 rotates
about the axis of the shaft 187 to engage the cut-out 232
with the pin 224. The profile of the cut-out 232 does not
easily permit release of the pin 224. Thus, the holding
lever 176 maintains the lifting lever 160, and therefore
the seat 140~ in the raised position. In this position,
due to the weight of~ the seat, the support rollers 184
moves along the cam faces 180 and 182 of the cam member to
rotate the seat 140 as described with respect to the firs~
embodiment. During seat rotation, the cam face 236 of the
cam plate 234 contacts the roller 226 to push the latter
downward. The holding lever 176 rotates counterclockwise
in response to the downward force to release ~he pin 224
from the cut-out 232. Thus, the holding lever 176 returns
- to its initial position, as shown in phantom line in
Fig. 12. By releasing the pin 224 from the cut out 232-,
the lifting lever 160 together with the lifting lever 162
is allowed ~o return the initial position thereof.
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Simultaneously, the latch 168 and 170 engage with the hooks
172 and 174 again in order to prevent the seat from
rota~ing.
~eferring to Fig. 14, there is il~ustrated a
modification of the second embodiment. In this
modification, an interlock mechanism is provided in order
to prevent passenger from subjecting themselves danger due
to sitting in the rotatable seat when it is unlatched. The
interlock mechanism therefore inhibits sitting while the
rotatable seat is in the raised position.
The interlock mechanism 250 comprises a blocking
lever 252 located immediately clockwise of the latch 168 so
that one end 254 thereof abuts the back of the latch in the
normal position. The blocking lever 252 is connected to a
lever 256 secured on the side of the pivotable seat back
258. The Iever 256 is integral with a pivotable piece 259
of a hinge mechanism 260. The hinge mechanism 260 includes
a stationary piece 262 secured to the seat cushion 264 and
an outer casing 266 covering the end of the axle of the
hinge mechanism 260. The outer casing 266 has a cut-out
268 on its circumference.
A locking lever 270 with an angled end 272 is
pivotably supported on the side of the seat cushion 264
near the outer casing 266. A bias spring 27~ has one end
secured to the stationary piece 262 of the hinge mechanism
and the other end attached to the locking lever 270 so as
to urge the lo~king lever 270 toward the outer casing 266.
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.The end 272 of the locking lever 270 in contact with the
outer casing 266 is angled toward the outer casing 266 so
that -it may engage ~ith the cut-out 268 when the seat back
258 is pivoted sufficient far toward the seat cushion 264.
A coaxial inner and outer cables 276 and 278 are
interposed between the blocking lever 252 and the lever
256. The outer cable 278 is secured to the bottom of the
seat cushion 264 by a bracket 280. The inner cable 276 is
movable through the outer cable according to the movement
of the lever 256. .The blocking lever 252 is pivotably
supported by a pivot 282 so that it can rotate hori~ontally
thereabout. As shown in Fig. 16, the blocking lever 252
has a forked end 284.: A connector pin 286 spans the space
288 between the arms 290 and 292-of the forked end 284. The.
connector pin 286 pivotably engages the end of the inner
cable 276. The inner cable 276 is movable through the
outer cable 278 according to movement of the lever 256.
I~ the normal position, the end 254 of the
blocking lever 252 prevents release of the latch 168.
Therefore, the actuating lever 164 cannot rotate about its
rotational axisO To enable the actuating lever 164 to be
operated, the seat back 258 must be held as illustrated by
: : phantom lines in Fig. 14. According to the rotation of the
: seat back 258 and thus the rotatable piece 259, the
lever 256 pivots counterclockwise in Fig. 14. The inner
cable 276 thus slides through the outer cable 278 so that
the blocking lever 252 is pulled to rotate about the
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pivot 282 to a position displaced from the latch 168 as
illustrated by phantom lines in Fig. 17. Thus, the
latch 168 is permitted to rotate to allow the actuating
lever 164 to be operated.
During the rotation of the seat back 258 about
the hinge axle, the cut out 268 of the outer casing 256 is
moved into opposition with the angled end 272 of the
locking lever 270 so as to engage the angled end 272. Due
to the engagement of the locking lever and the outer
casing, the seat back 258 is prevented from rotatiny back
to the normal position. The locking lever 270 is
maintained in this position by the force of the bias
spriny 274. The rotatable seat 140 can rotate normally
- about its rotational axis as described previously. When
the seat reaches the desired position, the seat 140 is
lowered to the initial position thereof. In this position,
the free end of the locking lever 270 abuts against the
upper surface o the seat support 152. The loclcing
lever 270 is thus rotated clockwise against the biasing
force of the spring 274 to disengage the angled end of
locking lever 270 ~and the cut out 268 of the outer
casing 266. This permits the seat back 258 to return to
the normal position.
As understood hereabove, the present invention
fulfills all of the objects and advantages sought therefor.
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