WO2008129993A1

WO2008129993A1 - Chair

Info

Publication number: WO2008129993A1
Application number: PCT/JP2008/057386
Authority: WO
Inventors: Kiyoyuki Okuyama; Seiji Otsuka
Original assignee: France Bed Co., Ltd.
Priority date: 2007-04-16
Filing date: 2008-04-09
Publication date: 2008-10-30
Also published as: JP2008264034A

Abstract

A chair, which is reclinable, comprises a chair main body (2), a leg body (6), which is disposed on a back surface of the chair main body, movable along a vertical direction of the chair main body, and holds the chair main body at an inclination by a first end, first drive means (26) for driving the leg body along the vertical direction of the chair main body, and a seat body rotatably connected to a first end of the chair main body on a front surface thereof.

Description

D E S C R I P T I O N

CHAIR

Technical Field

The present invention relates to a reclining chair, which can change the angle of holding the upper body of the user.

Background Art A type of chairs, a reclining chair that can change the angle of holding the upper body of the user, is known. The reclining chair has a seat portion on which the user sits and a back portion on which the upper body of the user leans. The back portion is rotatable with respect to the seat portion, and can be held at a specified angle. Therefore, when the user sits on the seat portion and reclines on the back portion, the angle of the upper body can be changed in" accordance with the angle of the back portion. Patent Document 1 discloses a reclining chair of the configuration as described above. The chair disclosed in Patent Document 1 has a leg body and a seat member provided substantially horizontally on the leg body. A leg base is rotatably attached to a front end of the seat member. A back rest member is rotatably connected at its lower end to a rear end of the seat member. An extension part is slidably connected to the back rest member. The extension part and the leg body are rotatably connected by a link respectively at one end and the other end of the link. Accordingly, when the back rest member is tilted back, the link rotates about the other end connected to the leg body in accordance with the tilt-back angle, while the extension part to which one end of the link is connected is sliding from the back rest member in the projecting direction. Thus, the leaned back upper body of the user can be held by the back rest member and the extension part.

[Patent Document 1] Jpn. Pat. Appln. KOKAI Publication No. 7-194450.

According to the chair disclosed in Patent Document 1, the back rest member is rotatably connected at its lower end to the rear end of the leg body. Therefore, the leg body supports the back rest member in the same condition both when the back rest member is upright and when it is tilted back. When the user tilts the back rest member backward, so that the extension part is slid in the projecting direction, the position in which the upper body is erect is changed to the reclining position in which the upper body is tilted back and supported by the back rest member and the extension part. In this time, the center of gravity of the user on the leg body is significantly shifted backward from the leg body. Therefore, in the reclining position in which the upper body of the user is tilted back, the leg body may easily fall backward. For example, if the user moves a lower limb or an upper limb in the state where the upper body is tilted back, the set condition of the leg body may be unstable and rattled. If the center of gravity is shifted excessively, the chair may overturn backward.

To prevent the chair from overturning backward, the dimension in the fore-and-aft direction of the leg body may be increased. However, if the dimension in the fore-and-aft direction of the leg body is increased, the chair as a whole may be large-sized or may look unattractive. Disclosure of Invention

An object of the present invention is to provide a chair, which keeps an improved stability of the chair main body by changing the support position of the chair main body backward in accordance with the shift of the center of gravity of the user, when the user' s position is changed from the state of erecting the upper body to the reclining state.

To achieve the above object, there is provided a chair, which is reclinable, comprising: a chair, which is reclinable, comprising: a chair main body; a leg body, which is disposed on a back surface of the chair main body, movable along a vertical direction of the chair main body, and holds the chair main body at an inclination by a first end; first drive means for driving the leg body along the vertical direction of the chair main body; and a seat body rotatably connected to a first end of the chair main body on a front surface thereof.

Brief Description of Drawings

FIG. 1 is a perspective view of a chair in an upright position according to an embodiment of the present invention, wherein a footrest body is rotated to a state in which groove portions are not visible. FIG. 2 is a perspective view of a chair in the upright position, wherein the footrest body is rotated to a state in which groove portions are exposed to a front surface.

FIG. 3 is a perspective view of a chair in a reclining position, wherein the footrest body is rotated to a state in which groove portions are located on an upper surface.

FIG. 4 is a perspective view of a chair in a reclining position, wherein the footrest body is rotated to a state in which groove portions are located on a lower surface. FIG. 5 is a back view showing a chair.

FIG. 6 is a side view of the chair in the upright position. FIG. 7 is a side view of the chair in the reclining position.

FIG. 8 is a front view showing a frame disposed in a chair main body. FIG. 9 is an explanatory view showing positions of a leg body with respect to the frame of the chair main body in the standing position and the reclining position.

FIG. 1OA is a partially omitted side view of the chair in the upright position, showing an angle of a seat body.

FIG. 1OB is an explanatory view of the chair in the upright position, showing drive means.

FIG. HA is a partially omitted side view of the chair in a reclining position, showing an angle of the seat body.

FIG. HB is an explanatory view of the chair in the reclining position, showing the drive means.

FIG. 12A is a front view of the leg body. FIG. 12B is a side view of the leg body.

FIG. 13 is a plan view of a first drive source which drives the leg body.

FIG. 14A is a plan view of a pair of guide rollers of the leg body provided in a first guide rail. FIG. 14B is a front view of the leg body shown in

FIG. 14A.

FIG. 14C is a side view of the leg body shown in FIG. 14A.

FIG. 15 is a block diagram of a control system.

Best Mode for Carrying Out the Invention An embodiment of the present invention will now be described with reference to the drawings.

A chair 1 shown in FIGS. 1 to 7 comprises a chair main body 2. The chair main body 2 has a curved shape, the back surface of which is convex and the front surface of which is concave. A pair of armrests 3, having a triangular cross section, is provided on the front surface of the chair main body 2 at the ends in the width direction of the chair main body 2. A seat body 4 and a footrest 5 are disposed between the armrests 3. The seat body 4 and the footrest 5 are rotatable, as will be described later.

A leg body 6 is attached to the back surface of the chair main body 2 so as to be movable in the vertical direction of the chair main body 2. The leg body 6 is movable steplessly between one end and the other end of the chair main body 2 indicated by chain lines and solid lines in FIG. 9. According to the position of the leg body 6, the angle of supporting the chair main body 2 can be changed. The angle of supporting the chair main body 2 shown in FIGS. 1, 2 and 6 corresponds to an upright position, and the angle of supporting the chair main body 2 shown in FIGS. 3, 4 and 7 corresponds to a reclining position. The chair main body 2 contains a frame 11, having a rectangular shape in a front view, as shown in FIG. 8. A pair of first guide rails 12, extending along the length of the frame 11 in the vertical direction, is provided at the end portions in the width direction of the frame 11. Each of the guide rails 12 has a U-shaped cross section with an open side directed inward in the width direction of the frame 11.

The leg body 6 is movably attached to the first guide rails 12. As shown in FIGS. 12A, 12B and 14A to 14C, the leg body 6 has a lateral rod 13, attachment plates 15 attached to the ends of the lateral rod 13, a pair of guide rollers 14 rotatably attached to each of the attachment plates 15 via support shafts 14a, an inverted Y-shaped leg member 16, one end of which is connected to a middle portion of the lateral rod 13, and a pair of casters 17 rotatably attached to the distal ends of the two branch portions of the leg member 16. The left and right pairs of guide rollers 14 of the leg body 6 are rotatably fitted in the respective first guide rails 12, and the leg member 16 is projected out of a slit 18 (shown in FIG. 5) formed in the back surface of the chair main body 2 and extending in the vertical direction (longitudinal direction) . As shown in FIGS. 9 and 14A to 14C, a U-shaped attachment part 20 having a cover plate 20a on its open side is inserted in and fixed to each of one end (the lower end) and the other end (the upper end) of each first guide rail 12, such that the cover plate 20a faces inward in the width direction of the chair main body 2. A support shaft 21a having a sprocket 21 is rotatably supported by each attachment part 20, with an axial line thereof being horizontal. A chain 22 is extended over the sprockets 21 in the upper and lower ends of the first guide rail 12. As shown in FIGS. 14A and 14B, a connecting element 23 is attached to each of the support shafts 14a, which rotatably support the guide rollers 14. One end and the other end of the chain 22 are connected to the connecting elements 23 attached to the paired support shafts 14a.

As shown in FIG. 13, each of the left and right sprockets 21 provided at one end of the first guide rail 12 is driven by a first drive source 26, integrally formed of a motor 24 and a decelerator 25, which constitute first drive means. The sprockets 21 are driven by the pair of left and right first drive sources 26 (only one of which is shown in FIG. 13), so that the chains 22 run along the pair of first guide rails 12. Thus, the leg body 6 moves along the first guide rails 12 via the connecting elements 23 to which the chains 22 are connected.

As a result, the chair main body 2 can be supported in the upright position as shown in FIGS. 1 and 2 or the reclining position as shown in FIGS. 3 and 4.

As shown in FIG. 8, the frame 11 contains a pair of second guide rails 28 extending in the vertical direction in an inner area between the first guide rails 12 in the width direction. A massage unit 29 is movably supported by the pair of second guide rails 28 via guide rollers 30 shown in FIGS. 1OA and HA. The massage unit 29 has a unit main body 31. Support members 32 are swingably disposed on the respective ends in the width direction of the unit main body 31. A pair of massage rollers 33 is rotatably mounted on the support members 32. A nut body (not shown) is provided on the back surface of the unit main body 31, and a screw shaft 34 shown in FIG. 8 is screwed into the nut body. The screw shaft 34 extends along the vertical direction inside the chair main body 2. A fourth drive source 35, as fourth drive means, which rotates the screw shaft 34, is disposed at one end, i.e., the lower end of the chair main body 2.

When the screw shaft 34 is rotated by the fourth drive source 35, the massage unit 29 moves from the one end (the lower end) to the other end (the upper end) or in the opposite direction along the second guide rails 28 inside the chair main body 2. In other words, the massage unit 29 is configured to reciprocate in the vertical direction inside the chair main body 2.

As shown in FIGS. 8 to HB, both side portions Ha of the frame 11 are shorter than the first guide rails 12. A seat frame 37 constituting the seat body 4 is located under the side portions, and side ends of the seat frame 37 in the width direction thereof is rotatably supported by the lower ends of the side portions Ha via support shafts 38. A seat cushion 38 is placed on the upper surface of the seat frame 37.

A second drive source 41, constituting second drive means, is rotatably supported between the ends of the pair of first guide rails 12 in one end of the chair main body 2. The second drive source 41 has a drive shaft 42, which is reciprocated in the axial direction. The distal end of the drive shaft 42 is pivotally connected to the other end (the front end) of the seat frame 37.

With the above configuration, when the drive shaft 42 is moved in the forward direction as shown in

FIG. 1OB, the seat body 4 forms a specified angle with respect to the front surface of the chair main body 2, and is maintained at an upright position. When the drive shaft 42 is moved in the backward direction as shown in FIG. HB, the seat body 4 becomes nearly parallel to the front surface of the chair main body 2 and is maintained in a flat position. As shown in FIGS. 1OA, 1OB, HA and HB, the seat body 4 has a support shaft 43, extending along the entire width of the frame 37 of the seat body 4 and rotatably connected to the other end of the frame 37. A side member 45, constituting the footrest 5, is connected to each of the ends of the support shaft 43 that project from the sides of the frame 37. As shown in FIG. 9, the side member 45 has a polygonal main portion 45a and an arm portion 45b extending from one side of the main portion 45a. A distal end of the arm portion 45b is connected to an end of the support shaft 43.

A footrest main body 46, having a cross section smaller than the main portion 45a, is disposed between the paired side members 45 such that it can be rotated and maintained at a specified angle by a click mechanism (not shown) . As shown in FIGS. 1 and 4, one of the four surfaces of the footrest main body 46 is a flat surface 46a. As shown in FIGS. 2 and 3, the other three surfaces have a pair of grooves 47, in which the calves of the lower limbs of the user are inserted. A leg massager 46b, schematically shown in FIGS. 1OA and HA, is incorporated in the footrest main body 46, so that the calves of the user inserted in the grooves 47 can be massaged.

As shown in FIGS. 1OB and HB, a third drive source 48, constituting third drive means, is pivotally connected at one end thereof to the lower surface of the seat frame 37. The third drive source 48 has a drive shaft 48, which is reciprocated. One end of a link 50 is pivotally connected to the distal end of the drive shaft 49. The other end of the link 50 is pivotally connected to the support shaft 43 extending at the front end of the seat frame 37.

With the above configuration, when the drive shaft 49 of the third drive source 48 is reciprocated, the support shaft 43 is rotated by the drive shaft 49.

Thus, the side member 45 of the footrest 5 is moved in association with the rotation.

As shown in FIG. 9, a tape-like pressure sensitive switch 51 is attached to the peripheral surface of the side member 45. When the rising angle of the chair main body 2 is changed, that is, when the position of the chair main body 2 is changed from the reclining position shown in FIG. 7 to the upright position shown in FIG. 6, the peripheral surface of the side member 45 is brought into contact with the floor. When the peripheral surface of the side member 45 is brought into contact with the floor, the pressure sensitive switch 51 detects the contact.

The pressure sensitive switch 51 outputs a detection signal to a control device 53 shown in

FIG. 15. While the signal from the sensitive switch 51 is being input to the control device 53, the control device 53 operates the second drive source 41, and drives the seat body 4 in the direction of rotating the front end upward about the one end pivotally connected to the frame 11. As a result, the footrest 5 is raised along with the seat body 4. Accordingly, the chair main body 2 is changed from the reclining position to the upright position without hindrance by the footrest 5.

As shown in FIGS. 1 and 2, side cushions 54, covered with a covering, are attached to the respective sides of the frame 11. Further, the front surface and the back surface of the frame 11 are covered with a covering 55. The lower end of each side cushion 54 has a curved surface. The curved surface, in contact with the floor, supports the one end (lower end) of the chair main body 2.

The covering 55 loosely covers the front surface of the frame 11, so that the user's back can securely fit on the massage rollers 33 of the massage unit 29 via the covering 55.

The first drive source 26, the second drive source 41, the third drive source 48 and the fourth drive source 35 control the drive by a remote controller 57 connected to the control device 53 as shown in FIG. 15. With the chair 1 with the above configuration, when the chair main body 2 is held in the upright position by the leg body 6 as shown in FIGS. 1, 2 and 10, the seat body 4 is maintained at a specified angle with respect to the chair main body 2.

When the chair body 2 is changed from the upright position shown in FIGS. 1 and 2 to the reclining position shown in FIGS. 3 and 4, the first drive source 26 is operated by means of the remote controller 57 connected to the control device 53 to move the leg body 6 upward from a middle portion of the back surface of the chair main body 2. As a result, the chair main body 2 is rotated about the one end in the direction of tilting the other end portion backward. Since the other end portion is supported by the leg body 6, the chair main body 2 can be changed from the upright position to the reclining position.

After the chair main body 2 has been changed to the reclining position, the angle of the seat body 4 with respect to the chair main body 2 can be changed suitably so that the user can comfortably sit on the seat body 4 in that state by operating the second drive source 41 by means of the remote controller 57.

When the first drive source 26 is operated by means of the remote controller 57 and the leg body 6 is moved along the first guide rails 12 to change the angle of holding the chair main body 2, the second drive source 41 may be automatically operated to change the angle of the seat body 4 with respect to the chair main body 2 to a suitable angle at which the user can sit comfortably.

When the chair main body 2 is in the reclining position as shown in FIGS. 3 and 4, and the user sits on the seat body 4 and tilts the upper body backward in that state, the center of gravity of the user on the chair main body 2 is shifted to an upper side as compared to the case of the upright position shown in FIGS. 1 and 2. However, since the shift of the center of gravity of the user on the chair main body 2 is associated with the shift of the leg body 6 which supports the chair main body 2, the center of gravity of the user does not excessively deviate from the leg body 6 to an upper side of the chair main body 2. Consequently, when the chair main body 2 is changed from the upright position to the reclining position, the support of the chair main body 2 by the lag body 6 is kept stable. Therefore, it is possible to prevent the chair main body 2 from being unstable or falling down backward due to a slight movement of the user.

In the upright position shown in FIG. 1 or the reclining position shown in FIG. 3, when the fourth drive source 35 is operated by means of the remote controller 57 to move the massage unit 29 in the frame 11 along the vertical direction of the chair main body 2, the back of the user, who sits down on the seat body 4, can be massaged.

When the footrest main body 46 of the footrest 5 is rotated to direct the grooves 47 frontward or upward as shown in FIG. 2 or 3, the user sitting on the seat body 4 can insert the calves of the lower limbs in the grooves 47. In this state, the leg massager 46b provided in the footrest main body 46 is operated by means of the remote controller 57, the user can subject both the back and the leg portions to massage simultaneously.

Alternatively, the user can selectively subject either the back or leg portions to massage.

In the reclining position, if the rotation angle of the footrest main body 46 is manually set such that the flat surface 46a of the footrest main body 46 of the footrest 5 faces up as shown in FIG. 4, the user can stretch the legs on the flat surface 46a. Thus, the user can take a relaxed posture.

In the upright position, if the footrest main body 46 is rotated such that the flat surface 46a of the footrest main body 46 of the footrest 5 faces frontward as shown in FIG. 1, the grooves 47 are not exposed and the chair is visually simplified.

To change the chair main body 2 from the reclining position shown in FIG. 7 to the upright position shown in FIG. 6, the leg body 6 is moved from the other end to the one end of the chair main body 2, with the result that the chair main body 6 is gradually raised from the tilted-back state.

In the reclining position, the angle formed between the seat body 4 and the chair main body 2 is small. Therefore, when the chair main body 2 is being raised, the peripheral surface of the side member 45 of the footrest 5 is brought into contact with the floor. The pressure sensitive switch 51, provided on the peripheral surface of the side member 5, detects that the peripheral surface of the side member 45 is brought into contact with the floor.

The pressure sensitive switch 51 outputs a detection signal to the control device 53. While the signal from the sensitive switch 51 is being input to the control device 53, the control device 53 outputs a drive signal to the second drive source 41 to moves the seat body 4 upward.

As a result, since the footrest 5 moves up along with the seat body 4, the chair main body 2 can smoothly be moved to the upright position, while the footrest 5 is being prevented from too strong hit against the floor. Then, when the chair main body 2 is brought to the upright position as shown in FIG. 6, the seat body 4 is kept at such an angle with respect to the chair main body 2 that allows the user to comfortably sit thereon.

In the embodiment described above, the control device 53 is configured such that the seat body 4 is moved upward only in a period when the pressure sensitive switch 51 is outputting the detection signal after detecting that the footrest 5 is brought into contact with the floor. However, the control device 53 may be configured to drive the seat body 4 upward by a predetermined angle when the pressure sensitive switch 51 outputs the detection signal.

Further, when the leg body 6 is moved to raise or tilt back the chair main body 2, the seat body 4 may be driven in association with the movement of the leg body 6. In other words, the first drive source 26 and the second drive source 41 may be synchronously controlled such that the second drive source 41 is operated in association with the first drive source 26.

In the above embodiment, the chair main body 2 has the curved shape, the back surface of which is convex and the front surface of which is concave. However, the chair main body 2 is not limited to the curved shape, but may have a substantially straight side surface .

Although the massage unit 29, which is reciprocated in the vertical direction of the chair main body, is disposed inside of the chair main body 2 in the above embodiment, the massage unit 29 is not necessarily provided in the chair main body 2. Industrial Applicability

According to this invention, the leg body is movable along the vertical direction on the back surface of the chair main body. When the chair main body is tilted backward to the reclining position, the leg body is moved from the lower portion to the upper portion on the back surface of the chair main body.

Therefore, when the chair main body is tilted back to the reclining position, the leg body supporting the chair main body also moves in accordance with the shift of the center of gravity of the user. Accordingly, the chair can be used in a stable condition.

Claims

C L A I M S

1. A chair, which is reclinable, comprising: a chair main body; a leg body, which is disposed on a back surface of the chair main body, movable along a vertical direction of the chair main body, and holds the chair main body at an inclination by a first end of the chair main body;

^"* first drive means for driving the leg body along the vertical direction of the chair main body; and a seat body rotatably connected to the first end of the chair main body on a front surface thereof.

2. The chair according to claim 1, further comprising second drive means for driving the seat body to a specified angle in accordance with the inclination of the chair main body.

3. The chair according to claim 1, wherein the chair main body has a pair of guide rails, which are spaced at a predetermined distance along a width direction crossing the vertical direction; and the leg body has guide rollers at a first end, the guide rollers being rotatably fit in the guide rails, and has a pair of casters at a second end, the casters being spaced at a predetermined distance along the width direction of the chair main body.

4. The chair according to claim 1, wherein the seat body is rotatably connected to a first end of the chair main body and a second end of the seat body is provided with a footrest, which is rotatable about the second end, the chair further comprising third drive means for driving the footrest to rotate about the second end of the seat body.

5. The chair according to claim 4, wherein the footrest includes a pair of side members rotatably connected to the second end of the seat body and rotated by the third drive means, and a footrest main body disposed between the pair of side members and configured to be rotatable and kept at a specified rotation angle, and the footrest main body also functions as a leg massager.

6. The chair according to claim 4, further comprising a pressure sensitive switch, which is provided on a peripheral surface of the footrest and detects a contact between the footrest and a floor, wherein when the chair main body is rotated from a reclining position to an upright position and the pressure sensitive switch detects the contact, the pressure sensitive switch outputs a detection signal and the seat body is moved in reply to the detection signal in a direction of raising the second end of the seat body.

7. The chair according to claim 1, wherein the chair main body includes a massage unit, which is movable along the vertical direction, the chair further comprising fourth drive means for driving the massage unit to reciprocate along the vertical direction.

8. The chair according to claim 1, wherein the chair main body has a curved shape, the back surface of which is convex.