Abstract:
A seatback-associated ottoman device includes: a memory mechanism that mechanically memorizes an unfolded angle position of an ottoman and cancels the memorized unfolded angle position when the unfolded angle of the ottoman is adjusted by the angle adjustment mechanism; and a prohibition mechanism that prohibits the canceling the memorized unfolded angle position of the memory mechanism when the ottoman is placed at the stored position.

Description:
INCORPORATION BY REFERENCE 
       [0001]    The disclosure of Japanese Patent Application No. 2013-024151 filed on Feb. 12, 2013 including the specification, drawings and abstract is incorporated herein by reference in its entirety. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The invention relates to a seat for a vehicle such as an automobile, an electric railcar, and an airplane, and particularly to a seatback-associated ottoman device in which an ottoman provided in front of a seat cushion of a vehicle seat is moved between an unfolded position and a stored position in association with an angle adjustment of a seatback with respect to the seat cushion. 
         [0004]    2. Description of Related Art 
         [0005]    There has been developed an ottoman-associated seat in which, when a seatback is tilted backward, a seat cushion is pressed forward and an ottoman is unfolded in front of the seat cushion, so that an occupant sitting on a seat is able to take a comfortable posture (see Japanese Utility Model Publication No. 3-45748 (JP3-45748 U)). Further, in such an ottoman-associated seat, a technique in which an unfolded angle of the ottoman is adjustable to a given angle has been also developed. In a seat that employs the latter technique, an adjusted unfolded angle of an ottoman is mechanically memorized, and when a seatback is subsequently tilted backward again so as to unfold the ottoman forward from a stored position, the ottoman is unfolded to an angle that is adjusted previously and then memorized. 
       SUMMARY OF THE INVENTION 
       [0006]    In the meantime, a memory of an unfolded angle position of the ottoman is cancelable at any time. For example, in a state where the seatback is placed at a normal usage position (an angle position to which the seatback is adjusted at the time of normal sitting) and the ottoman is placed at a stored position, if an operation to cancel the memory of the unfolded angle position of the ottoman is performed by mistake, a locking mechanism that memorizes an unfolded angle of the ottoman is unlocked, and that unfolded angle of the ottoman which is adjusted and stored previously is canceled. On that account, the unfolded angle of the ottoman at the time when the seatback is tilted backward next time to unfold the ottoman forward is different from the angle that an occupant adjusted earlier. The invention provides a vehicle seat and a seatback-associated ottoman device in each of which a memory canceled of an unfolded angle position of an ottoman is not performable except for a state where the ottoman is unfolded forward, so as to prevent the memory canceled of the unfolded angle position of the ottoman from being performed against the will of an occupant. 
         [0007]    A seatback-associated ottoman device according to a first aspect of the invention is a seatback-associated ottoman device for a vehicle seat in which an angle of a seatback is adjustable with respect to a seat cushion and which includes an ottoman provided in front of the seat cushion, and the seatback-associated ottoman device includes: an association mechanism that operates the seatback and the ottoman in association with each other, wherein when the seatback is placed at a normal usage position suitable for sitting, the association mechanism causes the ottoman to be stored in a stored position in a front lower portion of the seat cushion, and when the seatback is tilted backward from the normal usage position, the association mechanism moves the ottoman from the stored position to an unfolded position in front of the seat cushion so as to support legs of an occupant from a lower side; an angle adjustment mechanism that adjusts, to a given angle, an unfolded angle of the ottoman placed at the unfolded position; a memory mechanism that mechanically memorizes an unfolded angle position of the ottoman and cancels the memorized unfolded angle position when the unfolded angle of the ottoman is adjusted by the angle adjustment mechanism; and a prohibition mechanism that prohibits the canceling the memorized unfolded angle position of the memory mechanism when the ottoman is placed at the stored position. According to the first aspect, when the ottoman is placed at the stored position, canceling the memorized unfolded angle position of the ottoman which is memorized by the memory mechanism is prohibited by the prohibition mechanism regardless of an adjustment operation of the unfolded angle of the ottoman by the angle adjustment mechanism. On that account, in a state where the ottoman is placed at the stored position, even if the angle adjustment operation of the ottoman is performed by mistake, that unfolded angle position of the ottoman which is adjusted previously is not canceled, but kept memorized. 
         [0008]    Further, in the first aspect, the association mechanism may include a pivot link which is pivotally fixed to a base member supporting the vehicle seat and which is connected to the ottoman, a forward-backward moving member to be moved in a front-rear direction according to an angle adjustment of the seatback, and a connecting body that connects the forward-backward moving member to the pivot link so as to transmit their respective movements to each other, the connecting body being capable of changing a connecting position of the forward-backward moving member with respect to the pivot link; the angle adjustment mechanism may include a ratchet connected to the connecting body, and a locking mechanism that locks or unlocks the ratchet or the connecting body with respect to the forward-backward moving member, the locking mechanism being unlocked when the ottoman is placed at the unfolded position and the unfolded angle thereof is adjusted and when the angle adjustment of the seatback is performed; the memory mechanism may include a memory piece engaging with the ratchet while the angle adjustment of the seatback is performed, so as to memorize the unfolded angle of the ottoman, and a stopper that stops unfolding of the ottoman when the memory piece abuts therewith, the stopper being provided on a path of a movement of the memory piece that moves in association with a movement of the ratchet that moves along with a movement of the ottoman in an unfolded direction; and the prohibition mechanism may be a prohibition member that presses the memory piece so as to prevent the memory piece from being disengaged from the ratchet when the ottoman is placed at the stored position. According to the above configuration, when the locking mechanism is unlocked, the ratchet is freely movable together with the ottoman and the connecting body. At this time, if the angle adjustment of the seatback is not performed and the memory piece does not engage with the ratchet, the ratchet solely moves independently from the memory piece, so that the unfolded angle position of the ottoman is adjustable freely. After that, when the locking mechanism is locked, that unfolded angle position of the ottoman which is adjusted at that time is locked. On the other hand, when the angle adjustment of the seatback is performed, the locking mechanism is unlocked, and the ratchet moves along with the unfolding movement of the ottoman according to a backward tilting of the seatback. However, at this time, the memory piece engages with the ratchet and moves together with the ratchet, and therefore, that unfolded angle position of the ottoman which is adjusted previously is memorized, the ottoman is unfolded along with the backward tilting of the seatback, and the unfolding of the ottoman is stopped at a position where the memory piece abuts with the stopper, namely, the unfolded angle position memorized previously. However, when the ottoman is placed at the stored position, an engagement state of the memory piece with respect to the ratchet is maintained by the prohibition member in a state where the memory piece engages with the ratchet. Accordingly, even if the locking mechanism is unlocked, the memory of that unfolded angle position of the ottoman which is adjusted previously is not canceled at this time. When the seatback is tilted backward subsequently and the ottoman is unfolded in association therewith, the ottoman is maintained at the unfolded angle position that is set before the ottoman is moved from the unfolded position to the stored position. Accordingly, even if the locking mechanism is unlocked by mistake in the state where the ottoman is placed at the stored position, it is possible to prevent that unfolded angle position of the ottoman which is memorized previously, from being canceled against the will. 
         [0009]    A vehicle seat according to a second aspect of the invention is a vehicle seat in which an angle of a seatback is adjustable with respect to a seat cushion, and the vehicle seat includes: an ottoman provided in front of the seat cushion; and a seatback-associated ottoman device including: an association mechanism that operates the seatback and the ottoman in association with each other, wherein when the seatback is placed at a normal usage position suitable for sitting, the association mechanism causes the ottoman to be stored in a stored position in a front lower portion of the seat cushion, and when the seatback is tilted backward from the normal usage position, the association mechanism moves the ottoman from the stored position to an unfolded position in front of the seat cushion so as to support legs of an occupant from a lower side; an angle adjustment mechanism that adjusts, to a given angle, an unfolded angle of the ottoman placed at the unfolded position; a memory mechanism that mechanically memorizes an unfolded angle position of the ottoman and cancels the memorized unfolded angle position when the unfolded angle of the ottoman is adjusted by the angle adjustment mechanism; and a prohibition mechanism that prohibits the canceling the memorized unfolded angle position of the memory mechanism when the ottoman is placed at the stored position. 
         [0010]    Further, in the second aspect, the association mechanism may include a pivot link which is pivotally fixed to a base member supporting the vehicle seat and which is connected to the ottoman, a forward-backward moving member to be moved in a front-rear direction according to an angle adjustment of the seatback, and a connecting body that connects the forward-backward moving member to the pivot link so as to transmit their respective movements to each other, the connecting body being capable of changing a connecting position of the forward-backward moving member with respect to the pivot link; the angle adjustment mechanism may include a ratchet connected to the connecting body, and a locking mechanism that locks or unlocks the ratchet or the connecting body with respect to the forward-backward moving member, the locking mechanism being unlocked when the ottoman is placed at the unfolded position and the unfolded angle thereof is adjusted and when the angle adjustment of the seatback is performed; the memory mechanism may include a memory piece engaging with the ratchet while the angle adjustment of the seatback is performed, so as to memorize the unfolded angle of the ottoman, and a stopper that stops unfolding of the ottoman when the memory piece abuts therewith, the stopper being provided on a path of a movement of the memory piece that moves in association with a movement of the ratchet that moves along with a movement of the ottoman in an unfolded direction; and the prohibition mechanism may be a prohibition member that presses the memory piece so as to prevent the memory piece from being disengaged from the ratchet when the ottoman is placed at the stored position. According to the second aspect, it is possible to obtain the same effect as in the first aspect. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]    Features, advantages, and technical and industrial significance of exemplary embodiments of the invention will be described below with reference to the accompanying drawings, in which like numerals denote like elements, and wherein: 
           [0012]      FIG. 1  is a perspective view illustrating an appearance of a vehicle seat according to a first embodiment of the invention; 
           [0013]      FIG. 2  is a schematic view of an association mechanism for a seatback and an ottoman according to the first embodiment, and is a side view of a case where the ottoman is in a stored-position state; 
           [0014]      FIG. 3  is a schematic view similar to  FIG. 2  and is a side view of a case where the ottoman is in an unfolded-position state; 
           [0015]      FIG. 4  is an explanatory view illustrating a front end portion in the schematic view of  FIG. 3  and illustrating a change in an operation in a case where an unfolded position of the ottoman is adjusted by a link connection configuration; 
           [0016]      FIG. 5  is an explanatory view illustrating the front end portion in the schematic view of  FIG. 2  and illustrating an operating state in a state where the ottoman is placed at a stored position; 
           [0017]      FIG. 6  is an explanatory view around a front end portion of the seat cushion, illustrating a state where the seatback is tilted backward to a predetermined angle in an example that exemplifies the above embodiment; 
           [0018]      FIG. 7  is an explanatory view similar to  FIG. 6 , illustrating a state where the seatback is put back to a normal usage position in the above example; 
           [0019]      FIG. 8  is an explanatory view illustrating a state where the seatback is put back to the normal usage position similarly to  FIG. 7 , and a connecting body moves downward; 
           [0020]      FIG. 9  is an explanatory view similar to  FIG. 6 , illustrating a state where the seatback is tilted backward to an angle beyond the predetermined angle in the above example; 
           [0021]      FIG. 10  is an explanatory view illustrating a state where the seatback is tilted backward to the angle beyond the predetermined angle similarly to  FIG. 9  and the seatback is locked by a locking mechanism at this position; 
           [0022]      FIG. 11  is an explanatory view similar to  FIG. 6 , illustrating a state where an unfolded angle of the ottoman is adjusted in the above example; 
           [0023]      FIG. 12  is an enlarged explanatory view extracting and illustrating a configuration around the locking mechanism in the above example; 
           [0024]      FIG. 13  is an explanatory view to describe a movement state of the connecting body in the above example; 
           [0025]      FIG. 14A  is an enlarged sectional view taken along a line A-A in  FIG. 12  at a meshing position of gears; and 
           [0026]      FIG. 14B  is an enlarged sectional view taken along the line A-A in  FIG. 12  at a meshing-released position of the gears. 
       
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
       [0027]      FIGS. 1 to 5  illustrate a configuration of a vehicle seat  10  according to one embodiment. As illustrated in  FIG. 1 , the vehicle seat  10  has a configuration of, what is called, a single captain seat disposed in the second row in a vehicle including three rows of sheets, and includes a seatback  16  serving as a backrest for a sitting occupant, and a seat cushion  18  serving as a seat portion. In a front portion of the seat cushion  18 , an ottoman  14  that the sitting occupant is able to use as a foot rest is provided. In the present specification, unless especially noted, a front-rear direction is such that a “front” indicates a front-face direction that an occupant sitting on the seat cushion  18  with the seatback  16  as a backrest faces and a “rear” indicates its opposite direction. Further, a right and left direction of the occupant is regarded as a right and left direction, and an up-and-down direction of the occupant is similarly regarded as an up-and-down direction. In  FIG. 1 , a position change state is illustrated by a continuous line and a virtual line. A continuous-line position state indicates a normal usage position state that is a normal sitting state, and a virtual-line position state indicates a comfortable-posture position state. 
         [0028]    At the time when the seatback  16  illustrated in the continuous line is in the normal usage position state in which the seatback  16  is set upright so as to be used as a backrest, the ottoman  14  is in a stored-position state in which the ottoman  14  is folded in a front lower portion of the seat cushion  18 . When the seatback  16  is tilted from the normal usage position to a backward tilting position at which the occupant has a comfortable posture as illustrated in the virtual line, the ottoman  14  is changed to an unfolded-position state where the ottoman  14  is raised upward in association with that operation of the seatback  16 , so that the ottoman  14  is usable as a foot rest. In this embodiment, in a position state illustrated in the virtual line, it is possible to adjust, to a given position, a position of the ottoman  14  only in an unfolded state. In any unfolded-position state of the ottoman  14  thus adjusted, it is possible to perform a returning operation to put the ottoman  14  back into the stored-position state in association with an operation to raise the seatback  16  from the backward tilting position to its normal upright position. When the ottoman  14  is set to the unfolded-position state again due to an associated operation with the seatback  16  from a state where the ottoman  14  is put back to the stored position, the ottoman  14  is set to the same unfolded position as a previous unfolded position where the ottoman  14  had been set before the ottoman  14  was put back to the stored position. That is, a so-called memory function works. 
         [0029]    As described above, in the vehicle seat  10  according to the present embodiment, it is possible to perform a storing-unfolding operation on the ottoman  14  in association with an operation of the seatback  16 , and it is also possible to adjust, to a given position, a position state of the ottoman  14  thus set in the unfolded state in association with the operation of the seatback  16 . Further, it is possible to perform the returning operation to put the ottoman  14  back into the stored-position state in association with the seatback  16  while keeping the position state thus adjusted. Moreover, since the so-called memory function works, when the ottoman is moved to an unfolded position again in an associated manner, the ottoman is set to the same unfolded position as a previous position where the ottoman had been placed before the returning operation was performed. Thus, it is possible to improve convenience of the ottoman  14 . 
         [0030]    The following more specifically describes a configuration of each portion of the vehicle seat  10 . As illustrated in  FIG. 1 , the vehicle seat  10  includes a seat main body  12  including the seatback  16  and the seat cushion  18  as previously described, and the ottoman  14  is disposed in the front lower portion of the seat cushion  18 . The ottoman  14  is pivotally supported so as to be pivotally movable relative to the seat cushion  18  so that the ottoman  14  is able to take the stored position illustrated in the continuous line or the unfolded position illustrated in the virtual line. On an upper portion of the seatback  16 , a headrest  20  for supporting a head of a sitting occupant is disposed such that the headrest  20  is movable upward and downward in the up-and-down direction. Side walls  22  provided upright from a floor are disposed on right and left side portions of the seat main body  12 , and the seat main body  12  is connected to base frames  24 A of cushion frames  24  (described later) provided in the side walls  22  so that the seat main body  12  is supported by the base frames  24 A. The base frames  24 A are an example of a base member in the invention. Note that the vehicle seat  10  provided on the floor of the vehicle is provided on the floor via a slide rail (not illustrated herein), so that the vehicle seat  10  is movable slidably in the front-rear direction. As the slide rail, it is possible to use a well-known slide rail as described in Japanese Patent Application Publication No. 2010-221935 (JP2010-221935 A) or the like. Note that each of the side walls  22  on respective sides is configured such that its top face is set as an arm rest  22 A that a sitting occupant is able to use as an arm rest. 
         [0031]    A backward tilting operation from a continuous-line position of the seatback  16  illustrated in  FIG. 1  to a virtual-line position thereof relative to the seat cushion  18  is performed by a recliner (not shown) provided in a connection portion between the seat cushion  18  and the seatback  16 . Note that as a basic structure of the recliner, one described in Japanese Patent Application Publication No. 2011-116303 (JP2011-116303 A) or the like is usable, and a specific description thereof is omitted. The recliner includes a locking structure, and the locking structure is released by a pulling operation of a reclining lever (not shown) provided on a side face of the side wall  22  or the like. A spring force is also continuously given to the reclining lever in a direction to maintain the recliner in a locked state. In view of this, when the pulling operation of the reclining lever is canceled, the recliner is locked so as to maintain a position state where the seatback  16  is set. 
         [0032]    Next will be described an associated-operation configuration of the seatback  16  and the ottoman  14 , based on  FIGS. 2 to 5 . These figures schematically illustrate a configuration of a side view of the vehicle seat  10 .  FIGS. 2 and 5  illustrate an association position relationship in which the seatback  16  is in a normal upright position state and the ottoman  14  is in the stored-position state.  FIG. 3  illustrates an association position relationship in which the seatback  16  is tilted backward so as to be in the comfortable-posture position state and the ottoman  14  is in the unfolded-position state.  FIG. 4  illustrates an operating state in a case where only the unfolded-position state of the ottoman  14  is adjusted in a predetermined association position state in  FIG. 3 . Initially, the following describes the associated-operation configuration based on  FIG. 2 . The cushion frame  24  disposed in the seat cushion  18  is constituted by the base frame  24 A and a slide frame  24 B. The base frame  24 A and the slide frame  24 B are disposed in a sitting direction so as to be arranged in parallel with each other. The slide frame  24 B is disposed so as to be movable relative to the base frame  24 A in the front-rear direction, in  FIG. 2 . In view of this, a guide slot  50  having a shape of an elongated hole in the front-rear direction is formed in the base frame  24 A, and a slide pin  52  is integrally provided in the slide frame  24 B. The slide pin  52  engages with the guide slot  50  and slides so as to guide the slide frame  24 B while regulating a forward and backward movement of the slide frame  24 B. The slide frame  24 B is an example of a forward-backward moving member in the invention. A rear end portion (a right end portion in  FIG. 2 ) of the slide frame  24 B is rotatably connected, by a pin connection  48 , to a lower end portion of a side frame  16 A of the seatback  16 . The side frame  16 A of the seatback  16  is connected, by a pivotal support connection  46 , to a projecting portion  24 Aa, which is a rear portion of the base frame  24 A and is provided so as to extend upward, and the seatback  16  is tilted in the front-rear direction around the pivotal support connection  46 . Accordingly, when that upper portion of the seatback  16  which is above the pivotal support connection  46  is tilted backward so as to be in a comfortable posture state, this movement is transmitted to the slide frame  24 B via the pin connection  48  as a forward slide movement. On the other hand, a movement of the seatback  16  to be tilted forward from the backward tilting position, which is the comfortable posture state, is transmitted to the slide frame  24 B as a backward slide movement. Although not illustrated herein, the recliner is provided in a part  46  where the side frame  16 A of the seatback  16  is rotatably and pivotally supported by the projecting portion  24 Aa of the base frame  24 A. A front end portion (a left end portion in  FIG. 2 ) of the slide frame  24 B is connected, by a pivotal support connection  44 , to one end of a support frame member  14 A of the ottoman  14 , and the ottoman  14  is disposed at a position of the front lower portion of the seat cushion  18  in a state where the ottoman  14  is pivotally movable around the pivotal support connection  44 . Accordingly, the ottoman  14  also moves forward and backward along with the forward and backward movement of the slide frame  24 B. Note that a position state where the ottoman  14  hangs downward as illustrated in  FIG. 2  is the stored-position state, and the ottoman  14  is stored in the front lower portion of the seat cushion  18 . The unfolded state thereof is a state as illustrated in  FIG. 3 , which is a position state where the other end portion of the ottoman  14  pivots upward. The base frame  24 A is provided so as to be slidably movable relative to the floor via a slide rail (not shown). Because of this, the whole vehicle seat is provided so as to be movable forward and backward relative to the floor in the present embodiment. Note that a cushion pad constituting a seat portion of the seat cushion  18  is placed on the slide frame  24 B. Hereby, a sitting surface on a top face of the seat cushion  18  is provided integrally with the slide frame  24 B, and moves forward and backward along with the forward and backward movement of the slide frame  24 B. Accordingly, along with a backward tilting of the seatback  16 , the slide frame  24 B moves in the forward direction, and the sitting surface of the seat cushion  18  also moves in the forward direction. 
         [0033]    A front end portion (a left end portion in  FIG. 2 ) of the base frame  24 A and the ottoman  14  are connected by a first link member  26  (an example of a pivot link of the present invention). The first link member  26  is configured such that two elongated tabular link member A  28  and link member B  30  (examples of a moving member of the present invention) are connected by a pin connection  34 . One end of the link member A  28  is relatively pivotally connected, by a pin connection  32 , to the front end portion of the base frame  24 A, and similarly, the other end thereof is relatively pivotally connected, by the pin connection  34 , to one end of the link member B  30 . The other end of the link member B  30  is relatively pivotally connected, by a pin connection  36 , to a substantially central position (see  FIG. 2 ) of the support frame member  14 A of the ottoman  14 . In the front end portion of the slide frame  24 B, a slide portion  24 Ba is formed integrally therewith so as to extend downward, as illustrated in  FIG. 2 . The link member A  28  of the first link member  26  is disposed in a position state where surfaces of the link member A  28  and the slide portion  24 Ba are overlapped with each other. The slide portion  24 Ba and the link member A  28  disposed in such an overlapped position state include respective guide slots  38 ,  40  having a shape of an elongated hole and formed in a linear shape. The respective guide slots  38 ,  40  are disposed in such a relationship that when the ottoman  14  is placed in the stored-position state as illustrated in  FIG. 2 , respective members are provided and connected to each other so that respective axes X1, X2 of the respective guide slots  38 ,  40  coincide with each other. Note that an axis of the guide slot  40  formed in the slide portion  24 Ba is X1, and an axis of the guide slot  38  formed in the link member A  28  is X2. A common connecting pin member  42  (an example of a connecting body of the present invention) is passed through the respective guide slots  38 ,  40  so as to engage therewith. The connecting pin member  42  is slidably movable relative to the respective guide slots  38 ,  40 , and is able to change an unfolded angle of the ottoman  14  by changing a relative positional relationship of the connecting pin member  42  with respect to the guide slots  38 ,  40 . Note that, between the connecting pin member  42  and the slide portion  24 Ba, a locking mechanism (which will be described later in detail) for fixing an engaged position state of the connecting pin member  42  with respect to the guide slot  40  is provided. 
         [0034]    Next will be described an associated operation in the aforementioned associated-operation configuration of the seatback  16  and the ottoman  14 , based on FIGS.  2  to  5 . The state in  FIG. 2  illustrates a case where the vehicle seat  10  illustrated in  FIG. 1  is in the normal usage position state for a normal sitting posture illustrated in the continuous line. In this state, the seatback  16  is in a state where the seatback  16  stands upright and the ottoman  14  is the stored-position state where the ottoman  14  is stored in the front lower portion of the seat cushion  18 . In this state, the side frame  16 A of the seatback  16  is set upright in a state where the side frame  16 A is connected, by the pivotal support connection  46 , to the projecting portion  24 Aa of the base frame  24 A, and the slide frame  24 B connected, by the pin connection  48 , to the lower end portion of the side frame  16 A is placed at a relatively backward position with respect to the base frame  24 A. In this position state of the frames  24 A,  24 B, an engagement relationship between the slide pin  52  provided in the slide frame  24 B and the guide slot  50  provided in the base frame  24 A is in a state where the slide pin  52  engages with a rear portion of the guide slot  50 , in  FIG. 2 . Such an operation position state of the slide frame  24 B is transmitted to the ottoman  14  connected to the front end portion of the slide frame  24 B by the pivotal support connection  44 . A position control on the ottoman  14  is performed according to a control by the first link member  26  provided between the ottoman  14  and the front end portion of the base frame  24 A. The link member A  28  of the first link member  26  is connected, by the pin connection  32 , to the front end portion of the base frame  24 A in a pivotally movable manner. The pivoting thereof is performed along with a movement of the slide portion  24 Ba in the front-rear direction. This is because the connecting pin member  42  fixed to the slide portion  24 Ba of the slide frame  24 B by the locking mechanism (not shown) engages with the guide slot  38  provided in the link member A  28 , in a slidable manner in a direction along the axis X2. In the state illustrated in  FIG. 2 , the slide portion  24 Ba, i.e., the slide frame  24 B is placed at a most backward position, so that a lower end of the other end of the link member A  28  is also placed at a most backward position. This position state is transmitted, via the link member B  30  connected to the link member A  28  by the pin connection  34 , to that support frame member  14 A of the ottoman  14  which is connected to the link member B  30  by the pin connection  36 , thereby maintaining the ottoman  14  in the stored position state. 
         [0035]    The following describes a moving operation in which the seatback  16  is tilted backward as illustrated in the virtual line from the upright position state of the seatback  16  as illustrated in the continuous line in  FIG. 1 , thereby causing the ottoman  14  to be in the comfortable posture state where the ottoman  14  is unfolded upward.  FIG. 3  illustrates an operating state of the comfortable posture state. Along with a backward tilting of the seatback  16 , the side frame  16 A of the seatback  16  pivots clockwise around the pivotal support connection  46  as a pivot axis, so that the slide frame  24 B connected to the lower end portion thereof by the pin connection  48  is caused to slide forward. That is, the slide frame  24 B slides forward relative to the base frame  24 A. In this position state of the frames  24 A,  24 B, an engagement relationship between the slide pin  52  provided in the slide frame  24 B and the guide slot  50  provided in the base frame  24 A is in a state where the slide pin  52  engages with a front end of the guide slot  50 , in  FIG. 3 . Along with the forward movement of the slide frame  24 B as illustrated in  FIG. 3 , the slide portion  24 Ba formed integrally therewith also moves forward. Along with this, the connecting pin member  42  fixed to the slide portion  24 Ba pivots the link member A  28  clockwise around, as a pivot axis, a portion connected to the front end portion of the base frame  24 A by the pin connection  32  (in  FIG. 3 ), so as to move forward the lower end of the other end of the link member A  28 . The movement of the lower end of the link member A  28  is transmitted to the support frame member  14 A of the ottoman  14  via the link member B  30  connected by the pin connections  34 ,  36 , so as to pivot the ottoman  14  clockwise around, as a pivot axis, a portion connected to the slide frame  24 B by the pivotal support connection  44 , so that the ottoman  14  is unfolded upward. At this time, that portion of the ottoman  14  which is connected by the pivotal support connection  44  also moves forward, and thus, an unfolding operation of the ottoman  14  is performed while the ottoman  14  itself is moving forward. The pivoting of the link member A  28  around the pin connection  32  as a pivot axis at the time when the ottoman  14  pivots to be unfolded is performed such that, along with the forward movement of the connecting pin member  42 , the connecting pin member  42  slides inside the guide slot  38  of the link member A  28  in a direction toward the lower end of the link member A  28 . As such, in the present embodiment, the associated operation of the seatback  16  and the ottoman  14  is performed, so that the normal posture state as illustrated in  FIG. 2  is changed to the comfortable posture state as illustrated in  FIG. 3 . Note that the comfortable posture state as illustrated in  FIG. 3  is changed to the normal posture state as illustrated in  FIG. 2  by performing an operation reverse to the aforementioned operation. 
         [0036]    In the present embodiment, in the comfortable posture state in which the ottoman  14  pivots to be unfolded due to the associated operation along with the backward tilting of the seatback  16  as illustrated in  FIG. 3 , it is possible to adjust only an unfolded angle state of the ottoman  14  to a given angle in conformity to a preference of the sitting person, without changing a posture state of the seatback  16 . That is, while the seatback and the ottoman are operated in association with each other, a relative positional relationship between the seatback and the ottoman in the associated operation is adjustable. This operation is described below with reference to  FIG. 4 . That unfolded angle position of the ottoman  14  which is illustrated in a continuous line in  FIG. 4  is assumed a position Y1 at which the ottoman  14  is unfolded by pivoting in advance due to the associated operation with the seatback  16 . Adjustment of the position Y1 by pivoting the ottoman  14  so as to be changed to positions Y2, Y3 illustrated in virtual lines is performable in such a manner that the connecting pin member  42  fixed to the slide portion  24 Ba by the locking mechanism (not shown) is released so that the connecting pin member  42  slides inside the guide slot  40  formed in the slide portion  24 Ba. When the ottoman  14  is adjusted to the rotating position Y2, the connecting pin member  42  is released from the fixation to the slide portion  24 Ba so as to slide from a position t1 to a position t2, and the connecting pin member  42  is fixed again to the slide portion  24 Ba. Further, when the ottoman  14  is adjusted to the rotating position Y3, a fixation position of the connecting pin member  42  with respect to the slide portion  24 Ba is similarly moved from the position t1 to a position t3 in the guide slot  40 . At this time, along with the change of the rotating position of the ottoman  14 , the engaged position state of the connecting pin member  42  with respect to the guide slot  38  of the link member A  28  is also changed by sliding. Even in a case where the position of the connecting pin member  42  with respect to the slide portion  24 Ba is changed as such so as to change the unfolded angle of the ottoman  14 , when the seatback  16  is put back to a normal posture position and the ottoman  14  is put back to the stored position, the position of the ottoman  14  does not change regardless of the position of the connecting pin member  42 , and the ottoman  14  is placed at the stored position. This state is illustrated in  FIG. 5 . As described above, even in a case where the position of the connecting pin member  42  is changed to t1, t2, t3, when the ottoman  14  is placed at the stored position, the guide slot  40  of the slide portion  24 Ba and the guide slot  38  of the link member A  28 , in each of which the connecting pin member  42  slides, are placed at positions where the guide slot  40  and the guide slot  38  are overlapped with each other. Accordingly, the position of the link member A  28  does not change regardless of the position of the connecting pin member  42 . 
         [0037]    In  FIGS. 2 to 5 , one embodiment of the present invention is described based on schematic views. However, the following describes examples that realize the embodiment, based on  FIGS. 6 to 14 . Note that  FIGS. 6 to 11  illustrate only a layout of each part on a plane, and a three-dimensional positional relationship is ignored.  FIG. 6  illustrates a configuration around an ottoman operation portion at the time when the seatback is tilted backward by only a predetermined angle (e.g., a torso angle=40 degrees) from the normal usage position like  FIG. 3 , that is, a configuration around the front end portion of the seat cushion. In the descriptions of  FIGS. 2 to 5 , the connecting pin member  42  engages with the guide slot  40  of the slide portion  24 Ba. However, in  FIG. 6 , the connecting pin member  42  is supported by a slider  24 Bd, so that the slider  24 Bd is slidable along a guide rail  24 Bc of the slide portion  24 Ba. Here, the guide rail  24 Bc is provided so as to correspond to the guide slot  40  in  FIGS. 2 to 5 . Further, as enlarged and illustrated in  FIG. 12 , the connecting pin member  42  is also supported by the connecting link  56 B, and the connecting link  56 B is pivotally connected to a tip of a ratchet  56 A.  FIGS. 6 ,  12  illustrate the locking mechanism  54  that is not illustrated in  FIGS. 2 to 5 . Further, a memory mechanism  56  is provided adjacent to the locking mechanism  54 . The ratchet  56 A of  FIG. 12  is part of the memory mechanism  56 . When the locking mechanism  54  locks a position of the ratchet  56 A of the memory mechanism  56 , the position of the connecting pin member  42  is eventually locked via the connecting link  56 B. 
         [0038]    As illustrated in  FIG. 12 , the locking mechanism  54  is constituted by combining a cable link  54 B, a driving link  54 D, a stopper link  54 C, and a lock plate  54 E. The cable link  54 B is connected to a cable (not shown) that is operated when the unfolded angle of the ottoman is adjusted, and a cable (not shown) from the reclining lever (not shown) that is operated when a tilted position of the seatback is adjusted. The cable link  54 B is connected to the slide portion  24 Ba pivotally around a connecting shaft  54 Ba via which the cable link  54 B is connected to the driving link  54 D. The driving link  54 D is integrally connected to the cable link  54 B via the connecting shaft  54 Ba, and when the cable link  54 B is pivoted, the driving link  54 D is also pivoted together. The driving link  54 D is configured to have a triangular shape. The connecting shaft  54 Ba is provided in one of vertices of the triangular shape, and the stopper link  54 C and the lock plate  54 E are connected respectively to the other two vertices via connecting pins  54 Da,  54 Db in a relatively pivotal manner. The stopper link  54 C is pivotally fixed to the slide portion  24 Ba around a pivot shaft  54 Ca provided in an end portion of the stopper link  54 C. The lock plate  54 E is configured to have a triangular shape. One of vertices of the triangular shape is connected to the connecting pin  54 Db, one of the other two vertices is pivotally fixed to the slide portion  24 Ba around a pivot shaft  54 Ea, and the other one of the other two vertices includes a lock pin  54 Eb. Moving ranges of the connecting pins  54 Da,  54 Db, the lock pin  54 Eb, and the connecting shaft  54 Ba are regulated respectively by guide slots  25 A,  25 B,  25 C, and  25 D.  FIG. 12  illustrates positions of the connecting pins  54 Da,  54 Db, the lock pin  54 Eb, and the connecting shaft  54 Ba at the time when a cable (not shown) for adjusting the unfolded angle of the ottoman is pulled so that the cable link  54 B is pivoted as shown in a continuous line. When an operation of the cable is canceled and the cable link  54 B is put back from a pivoting state and set to a position as shown in a virtual line, the connecting pins  54 Da,  54 Db, the lock pin  54 Eb, and the connecting shaft  54 Ba move to respective positions opposite to positions illustrated in  FIG. 12  within the guide slots  25 A,  25 B,  25 C, and  25 D. Note that the guide slots  25 A,  25 B,  25 C and  25 D are provided in a cover (not shown) provided so as to entirely cover the slide portion  24 Ba. 
         [0039]    As illustrated in  FIG. 12 , when the ottoman  14  is placed at the stored position, a tip of an unlock bracket  54 A is placed at a position where the tip abuts with the connecting pin  54 Da. At this time, even in a case where the operation of the cable is canceled and the cable link  54 B is placed at the position shown in the virtual line, when the connecting pin  54 Da is pressed by the unlock bracket  54 A, the cable link  54 B is pivoted via the driving link  54 D so as to be placed at the position shown in the continuous line. On that account, when the ottoman  14  is placed at the stored position, the locking mechanism  54  forcibly enters an unlock state regardless of the operation of the cable. Although not illustrated herein, the unlock bracket  54 A is fixed to the base frame  24 A (see  FIG. 2 ), and its position does not change regardless of the tilted position of the seatback. In a state illustrated in  FIG. 12 , a lock pin  54 Eb of the locking mechanism  54  does not mesh with a gear portion  56 Aa of the ratchet  56 A of the memory mechanism  56 . On this account, the locking mechanism  54  does not lock the position of the ratchet  56 A of the memory mechanism  56 . In a state where the operation of the cable is canceled or the ottoman  14  is placed at the unfolded position, the cable link  54 B is placed at the position shown in the virtual line, and the links  54 D,  54 C and the lock plate  54 E pivot, so that the lock pin  54 Eb of the locking mechanism  54  mesh with the gear portion  56 Aa of the ratchet  56 A of the memory mechanism  56 , thereby resulting in that the locking mechanism  54  locks the position of the ratchet  56 A of the memory mechanism  56 . As a result, the position of the connecting pin member  42  with respect to the slide portion  24 Ba is locked. 
         [0040]      FIG. 7  illustrates a state when the seatback is placed at the normal usage position. Note that the following description refers to  FIGS. 12 ,  13  to facilitate understanding. At this time, the ottoman  14  is placed at the stored position, and unlike the above description, the locking mechanism  54  does not lock the position of the ratchet  56 A of the memory mechanism  56 . Further, the guide slot  38  of the link member A  28  is parallel to the guide rail  24 Bc of the slide portion  24 Ba, and a path of movement of the connecting pin member  42  by the guide slot  38  coincides with a path of movement of the connecting pin member  42  by the guide rail  24 Bc. In the meantime, a tension spring  56 Ab (an example of a moving mechanism of the present invention) is provided over between the ratchet  56 A and the base frame  24 A (see  FIG. 2 ). On that account, the ratchet  56 A is biased counterclockwise around a pivot shaft  56 Ac by a tensile force of the tension spring  56 Ab. As a result, as illustrated in  FIG. 7 , when the seatback is placed at the normal usage position and the ottoman  14  is placed at the stored position, the connecting pin member  42  is moved from a position as illustrated in  FIGS. 7 ,  12  to a position as illustrated in  FIGS. 8 ,  13  by the tensile force of the tension spring  56 Ab. When the connecting pin member  42  is moved to a position away from the pin connection  32  of the guide slot  38  of the link member A  28  as such, a torque required to pivot the link member A  28  by the connecting pin member  42  is reduced. This is because a moment arm at the time of pivoting the link member A  28  becomes long. This makes it possible to reduce an operating force at the time of tilting the seatback backward to move the ottoman  14  to the unfolded position, from the state where the seatback is placed at the normal usage position and the ottoman  14  is placed at the stored position. 
         [0041]      FIG. 9  illustrates a state where the seatback is tilted backward largely beyond the above-mentioned predetermined angle (e.g., a torso angle=51 degrees). At this time, as described above, the link member A  28  is pivoted clockwise via the connecting pin member  42  due to a forward movement of the slide frame  24 B (see  FIG. 3 ) and the slide portion  24 Ba, the ottoman  14  is unfolded forward via the link member B  30 . Further, the support frame member  14 A of the ottoman  14  moves the ottoman  14  forward in  FIG. 9 , as compared with a case where the ottoman  14  is placed at the stored position as illustrated in  FIGS. 7 ,  8 . This is because the support frame member  14 A includes a mechanism for moving the ottoman  14  forward as the unfolded angle of the ottoman  14  increases. Note that  FIG. 9  assumes that the connecting pin member  42  is placed in the upper end portion of the slide portion  24 Ba.  FIG. 10  illustrates a state where an operation to tilt the seatback backward is stopped in a state where the seatback is tilted largely backward similarly to  FIG. 9 . At this time, an operation of the reclining lever (not shown) that is operated to tilt the seatback backward is canceled, so that the lock pin  54 Eb of the locking mechanism  54  meshes with the gear portion  56 Aa of the ratchet  56 A of the memory mechanism  56  and the locking mechanism  54  locks the position of the ratchet  56 A of the memory mechanism  56 . 
         [0042]      FIG. 11  illustrates a state where the seatback is tilted largely backward similarly to  FIG. 10  and only the angle of the ottoman  14  is adjusted without changing a tilted position of the seatback. Note that, in  FIG. 11 , a configuration of the memory mechanism  56  is simplified. In order to adjust the angle of the ottoman  14  as such, a cable (not shown) for operating the locking mechanism  54  is operated as described above to unlock the locking mechanism  54 , and in this state, the angle of the ottoman  14  is adjusted to a given angle. The angle adjustment of the ottoman  14  is performable by adjusting a gravity to be added to the ottoman  14  by legs put on the ottoman  14 . A tension spring  14 B (an example of a biasing mechanism of the present invention) is provided over between the pivotal support connection  44 , which is a rotating center of the ottoman  14 , and the link member B  30 , so that the ottoman  14  is biased by a tensile force of the tension spring  14 B from the stored position to the unfolded position. As described based on  FIG. 7 , the tension spring  56 Ab is provided over between the ratchet  56 A and the base frame  24 A (see  FIG. 2 ). The ratchet  56 A is biased counterclockwise around the pivot shaft  56 Ac by the tensile force of the tension spring  56 Ab. Here, the tension spring  14 B is set so that the tensile force is larger than that of the tension spring  56 Ab. As a result, in a state where the locking mechanism  54  is unlocked, the ottoman  14  is biased by the tensile force of the tension spring  14 B in a direction where the unfolded angle is increased. Accordingly, by adjusting the force to be added to the ottoman  14  as described above, it is possible to adjust the unfolded angle of the ottoman  14 . When the locking mechanism  54  is unlocked so as to adjust the angle of the ottoman  14  as such, the connecting pin member  42  moves along the guide rail  24 Bc and the position of the connecting pin member  42  within the guide slot  38  of the link member A  28  is changed. That is, a distance between the pin connection  32  and the connecting pin member  42  is changed. As this distance is shorter, a force to be added to the link member A  28  via the link member B  30  is amplified by a principle of a “lever” and transmitted to the connecting pin member  42 . Accordingly, when the unfolded angle of the ottoman  14  is set to be large, it is possible to amplify the force to be added to the ottoman  14  from the legs and to transmit it to the slide portion  24 Ba, thereby making it possible to decrease an operating force at the time when the seatback is raised toward the normal usage position from a state where the seatback is tilted backward. Note that in a state where the ottoman  14  is placed at the stored position like  FIGS. 7 ,  8 , the tension spring  14 B is placed at a position where the link member A  28  does not receive or hardly receives a rotation moment due to the tensile force of the tension spring  14 B, so that the ottoman  14  is not biased toward the unfolded position. On that account, as described based on  FIG. 8 , when the ottoman  14  is placed at the stored position, the connecting pin member  42  is moved by the tensile force of the tension spring  56 Ab to a position away from the pin connection  32 . However, the tensile force of the tension spring  14 B does not affect the movement. 
         [0043]    Next will be described the memory mechanism  56 . As illustrated in  FIG. 12 , the gear portion  56 Aa is provided along an arc around the pivot shaft  56 Ac, at a position apart from the pivot shaft  56 Ac of the ratchet  56 A, and gears are formed on both an outer peripheral side and an inner peripheral side of the arc of the gear portion  56 Aa. The gear on the outer peripheral side is formed so that the lock pin  54 Eb of the locking mechanism  54  meshes therewith, and a memory plate  56 F is provided so as to mesh with the gear on the inner peripheral side. As illustrated in  FIG. 14 , the memory plate  56 F engages with the gear portion  56 Aa, and is movable between a position where the gear on the inner peripheral side of the gear portion  56 Aa meshes with that gear (not shown) of the memory plate  56 F which is provided opposed to the gear as illustrated in  FIG. 14A  and a position where the gear of the memory plate  56 F is away from the gear on the inner peripheral side of the gear portion  56 Aa so that their meshing is released as illustrated in  FIG. 14B . A cam  56 C is provided adjacent to the memory plate  56 F. When the memory plate  56 F is pushed by the cam  56 C, the memory plate  56 F moves to a position where the memory plate  56 F meshes with the gear on the inner peripheral side of the gear portion  56 Aa. A tension spring  56 Fa is provided over between the memory plate  56 F and the pivot shaft  56 Ac of the ratchet  56 A, and when the memory plate  56 F is not pushed by the cam  56 C, the memory plate  56 F is separated from the gear on the inner peripheral side of the gear portion  56 Aa. A stopper  56 D and a guide  56 E are provided respectively at positions corresponding to respective ends of the memory plate  56 F. The stopper  56 D regulates a range in which the memory plate  56 F moves along its arc shape together with the gear portion  56 Aa. The guide  56 E is configured as follows: when the memory plate  56 F meshes with the gear on the inner peripheral side of the gear portion  56 Aa, the guide  56 E allows the memory plate  56 F to move along its arc shape; and when the memory plate  56 F is separated from the gear on the inner peripheral side of the gear portion  56 Aa, the guide  56 E regulates the memory plate  56 F from moving along its arc shape. Accordingly, in a state where the memory plate  56 F does not mesh with the gear on the inner peripheral side of the gear portion  56 Aa, the stopper  56 D and the guide  56 E prevent the memory plate  56 F from moving in either of front and back directions along the arc shape. In the meantime, in a state where the memory plate  56 F meshes with the gear on the inner peripheral side of the gear portion  56 Aa, the stopper  56 D and the guide  56 E move the memory plate  56 F along the guide  56 E together with the gear portion  56 Aa of the ratchet  56 A, but do not allow the memory plate  56 F to move forward from the stopper  56 D. The stopper  56 D and the guide  56 E are formed on an inner wall of the abovementioned cover (not shown) of the slide portion  24 Ba. Further, the cam  56 C is connected to the cable  58 . When the reclining lever (not shown) that is operated to adjust the tilted position of the seatback is operated, the cable  58  pulls the cam  56 C as illustrated in  FIG. 12 , so as to pivot the cam  56 C around its pivot shaft  56 Cb. At this time, the cam  56 C pushes the memory plate  56 F so as to move the memory plate  56 F to the position where the memory plate  56 F meshes with the gear on the inner peripheral side of the gear portion  56 Aa. When the operation on the reclining lever (not shown) is ended, the cable  58  is put back and the cam  56 C is pulled by the tension spring  56 Ca and pivots, thereby removing the press against the memory plate  56 F, so that the memory plate  56 F is separated from the gear on the inner peripheral side of the gear portion  56 Aa. 
         [0044]    Next will be described an action of the memory mechanism  56 . In a state where the seatback is tilted backward from the normal usage position and the ottoman  14  is placed at the unfolded position, when the cable (not shown) is operated to unlock the locking mechanism  54  and the unfolded angle of the ottoman  14  is adjusted to a given angle as described above, the connecting pin member  42  is moved to a position according to the unfolded angle of the ottoman  14 . At this time, the ratchet  56 A connected to the connecting pin member  42  is also moved together with the gear portion  56 Aa. That is, the gear portion  56 Aa is moved along a lower surface of the guide  56 E. On the other hand, in a state where the reclining lever (not shown) is not operated, the cam  56 C does not press the memory plate  56 F. Accordingly, even if the memory plate  56 F is separated from the meshing state with the gear portion  56 Aa and the gear portion  56 Aa moves along the lower surface of the guide  56 E, the memory plate  56 F is stopped by the guide  56 E and does not move together with the gear portion  56 Aa. When the adjustment of the unfolded angle of the ottoman  14  is completed and the operation of the cable (not shown) is ended, the lock pin  54 Eb of the locking mechanism  54  meshes with the gear on the outer peripheral side of the gear portion  56 Aa, and the unfolded angle of the ottoman  14  is locked. When the seatback is put back to the normal usage position or the backward tilting angle of the seatback is changed after that, the cable  58  is pulled so as to pivot the cam  56 C at the time of operating the reclining lever (not shown), so that the memory plate  56 F is placed to a position where the memory plate  56 F meshes with the gear portion  56 Aa. In view of this, even in a case where the locking mechanism  54  is unlocked along with the operation of the reclining lever, when the ratchet  56 A moves along with changes of the unfolded angle of the ottoman  14 , the memory plate  56 F also moves together. Thus, a previously adjusted position of the ottoman  14  is memorized and maintained as the unfolded angle position of the ottoman  14  along with the backward tilting of the seatback. As described earlier, when the seatback is placed at the normal usage position and the ottoman  14  is placed at the stored position, the locking mechanism  54  is unlocked. Accordingly, the connecting pin member  42  moves downward along the guide slot  38 , and the ratchet  56 A also pivots so that the gear portion  56 Aa moves below the guide  56 E. At this time, the gear portion  56 Aa moves together with the memory plate  56 F, and thus, that unfolded angle of the ottoman  14  which is adjusted is kept memorized. Accordingly, in this state, even if the locking mechanism  54  is unlocked, a memory of the unfolded angle position of the ottoman is not canceled. On that account, when the reclining lever is operated subsequently to tilt the seatback backward and the link member A  28  is accordingly pushed by the connecting pin member  42  so that the ottoman  14  is moved from the stored position to the unfolded position, the tension spring  14 B overcomes a biasing force of the tension spring  56 Ab so as to unfold the ottoman  14  by adjustment of the gravity of the legs as described above, so that the unfolded angle is determined at a position where an end portion of the memory plate  56 F abuts with the stopper  56 D. This unfolded angle is an angle memorized when the memory plate  56 F meshes with the gear portion  56 Aa as described above, and thus, the unfolded angle of the ottoman  14  is set to an angle memorized by the memory mechanism  56 . Note that an unfolded operation of the ottoman  14  is stopped at the position where the end portion of the memory plate  56 F abuts with the stopper  56 D, but it is still possible to continue the backward tilting operation of the seatback. 
         [0045]    Specific embodiments have been described above, but the invention is not limited to the appearances and the configurations described in the above embodiments, and various modifications, additions, and deletes are performable as far as they do not change a gist of the invention. For example, 1. a prohibition mechanism is not limited to one described in the above example which is configured such that when the ottoman is placed at the stored position, the ratchet moves so that the memory plate is pressed by the guide serving as a prohibition member, thereby preventing the memory plate from being separated from the gear portion of the ratchet. The prohibition mechanism may be configured such that the ratchet does not move and the memory plate is pressed by the gear portion of the ratchet due to the prohibition member.