JP3477014B2 - Folding chair - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a folding chair which can be folded flat when not in use. 2. Description of the Related Art For example, folding chairs are sometimes prepared in a conference room or the like in case the number of participants increases, and when the chairs are not used, they are folded flat and accommodated. Something is left in the corner of the room. Usually, a folding chair has a front leg member having an upper portion formed on a backrest, and a front end side of a seat body is rotatably connected to a middle portion of the front leg member. An intermediate portion of a rear leg member is pivotally connected to a rear end side of the seat body via a link. The upper end of the rear leg member is pivotally connected to a middle part of the front leg member. Accordingly, by rotating the front end side of the seat body upward, the front leg member, the rear leg member and the seat body can be folded flat so as to be joined. However, according to the folding chair having such a structure, the lower surface of the seat is exposed to the front side when folded, so that the appearance of the folded state is extremely poor. [0006] The chair is used in such a manner that the seat body is horizontally lowered by opening the front leg member with respect to the rear leg member. In use, the seat body in the lying state is not held at all in that state. [0007] Therefore, depending on the sitting state, not only the seat body in the lying state may turn in the upright direction and the stability is poor, but also when a large load is applied to the rear end side of the seat body, the front legs may be damaged. While the member and the rear leg member are closed, the seat body rapidly rotates to the upright state, and there is a risk that a finger may be pinched between the front leg member and the rear leg member. Further, in the folding chair having the above structure, the front leg member, the rear leg member, and the seat member are not securely held in the joined state in the folded state. However, there are cases in which the seat body falls down due to the opening, so that it was sometimes difficult to handle. [0009] As described above, in the conventional folding chair, the lower surface of the seat is exposed to the front side in the folded state, so that the appearance in the folded state may be reduced. In addition, since the seat body is not securely held in each state at the time of use or at the time of non-use when folded, it is difficult to use or inconvenient to carry. [0010] An object of the present invention is to provide a folding chair in which the lower surface of the seat body is not exposed to the front side when folded, and the seat body can be securely held when used or not used. It is in. According to a first aspect of the present invention, there is provided a folding chair which can be folded flat when not in use. The folding chair has a backrest formed on an upper part and a lower part formed on a rear leg. a guide groove respectively in the vertical direction is formed along its upper end and the lower end to the middle portion upper engaging recess <br/> portion and the lower engaging recess formed in the rear leg member, the lower A front leg member formed on the front leg and having an upper portion rotatably connected to an upper end portion of the rear leg member; and a seat body having a front end side lower surface rotatably connected to a vertically intermediate portion of the front leg member. The seat body is elastically urged in the axial direction toward the rear end of the lower surface of the seat body and is slidably engaged with the guide groove. When in the state, it engages with the lower engagement recess and when in the upright state, it A slide shaft to prevent rotation of the seat body engages with the upper engaging recess, is formed in the vertically intermediate portion of the guide groove
While making the lower side of this guide groove deeper than the upper side,
Due to the load in the upright direction applied to the seat body, the slide
When the slide shaft is disengaged from the lower engagement recess, the slide
Shaft engages to prevent the seat body from rotating in the upright direction.
And a stepped portion . According to the first aspect of the present invention, when the pair of leg members is closed, the seat body slides in the ascending direction at the rear end side with the front end side as a fulcrum, and the upper surface of the seat body is folded in the folded state. Since it is on the front side, the lower surface is not exposed, and the slide shaft is formed at the lower end of the guide groove and the upper part in the lower part of the guide groove at the time of use when the seat body is folded down and when not in use when standing upright Since the seats are engaged with the upper engaging recesses respectively formed in the above, the seat body is reliably held in the lying state when used and the standing state when not in use. [0013] Moreover, the lower the intermediate portion of the guide groove by forming the stepped portion deeper than the upper, for example, the seat body guide shaft is inadvertently disengaged from the lower engagement recess upright direction during use Even if the user tries to rotate, the guide groove engages with the stepped portion, so that the seat body is prevented from rotating in the upright direction. An embodiment of the present invention will be described below with reference to the drawings. Folding chair 1 shown in FIGS. 1 and 2
Has a rear leg member 2 and a front leg member 3. The rear leg member 2
As shown in FIGS. 1 (a) and 1 (b), the lower ends of a pair of first strips 4 which are spaced apart in parallel at a predetermined interval are connected by a connecting bar 5, and the lower part is a rear leg 6, A backrest 7 is attached to the upper end. The first band plate 4 is formed by bending a plywood so as to protrude forward, and a guide groove 8 is formed along an up-down direction on an inner side surface of an intermediate portion thereof. FIGS. 5A and 5B show an intermediate portion of the guide groove 8 in the vertical direction.
As shown in FIG. 7, a step 8a is formed to make the lower part of the guide groove 8 deeper than the upper part, a lower engaging concave part 8b is formed at the lower end, and an upper engaging concave part 8c is formed at the upper end. . An inclined portion 8d is formed between the step portion 8a and the lower engaging concave portion 8b to gradually reduce the depth of the guide groove 8 toward the lower end. Therefore, even if the step 8 is formed in the middle of the guide groove 8, the lower engaging recess 8b can be set to the same depth as the upper engaging recess 8c. The front leg member 3 comprises a pair of second strips 11 located on both sides of the rear leg member 2. The second band plate 11, like the first band plate 4, is formed by bending a plywood so as to protrude forward. Then, the second band plate 11
The lower part is a front leg 12, and the upper end part is rotatably connected to a bracket 9 (shown in FIG. 3A) embedded on both sides in the width direction of the backrest 7 by a support shaft 13. As shown in FIG. 4, the connecting portions 14a at both ends of the connecting fitting 14 bent into a crank shape are connected. The intermediate portion 14b of the connection fitting 14 is biased toward the front side of the chair 1, which is one end side in the thickness direction of the second band plate 11. Note that a connection support portion between the bracket 9 and the support shaft 13 is a first connection point A. FIG. 4 shows a connecting portion 14a of the connecting fitting 14.
The tongue piece 15 is provided as shown in FIG.
Are rotatably connected by a support shaft 17. This connecting portion is referred to as a second connecting point B. A lower surface on the front end side of a rectangular plate-shaped seat 18 is connected and fixed to the upper surface of the mounting bracket 16. A bracket 19 located between the pair of first strips 4 is attached to a middle portion in the width direction on the rear end side of the lower surface of the seat body 18. As shown in FIG. 6, the bracket 19 is provided with a cylindrical bearing 21 along the width direction of the seat body 18. A pair of slide shafts 22 are slidably inserted into the bearing 21. A pair of slide shafts 22
A spring 23 is provided between one end of the spring. This spring 23
The other end of the pair of slide shafts 22 is
Biased in a direction to protrude therefrom. A pair of long holes 24 are formed in the bearing 21 along the axial direction. A knob 25 is attached to the slide shaft 22 from each long hole 24. Therefore, each slide shaft 22 is slidable in the axial direction within a range in which the knob 25 can move in the long hole 24. That is, the slide shaft 22 is connected to the spring 23
The other end is not disengaged from the guide groove 8 by the urging force of the above, and the other end is disengaged from the guide groove 8 by engagement with the lower engagement recess 8b and the upper engagement recess 8c formed at the lower end and the upper end of the guide groove 8. It can slide between the immersion position. The slide center of the slide shaft 22,
That is, the axis of the slide shaft 22 is set as the support point C of the seat body 18. The lower engaging recess 8b and the upper engaging recess 8
c is formed at the same depth as each of the engagement recesses 8.
The slide shaft 22 can be reliably engaged with the b and 8c. In the folding chair 1 having the above structure, as shown in FIG. 2A, the rear leg member 2 and the front leg member 3 are opened with the first connection point A as a fulcrum, and the slide shaft 22 is connected to the guide groove 21. , The second connection point B and the support point C are substantially at the same height, and the seat body 18 is supported substantially horizontally.
When the user sits on the seat body 18 in this state, the load is applied to the first and second strips 4 and 1 of the rear leg member 2 and the front leg member 3.
Join 1 The strips 4 and 11 are formed so as to be convex toward the front side. Therefore, each of the strips 4 and 11 exhibits high rigidity with respect to the load going from the convex side to the concave side, and conversely, has elasticity with respect to the load going from the concave side to the convex side. Therefore, the folding chair 1 has sufficient strength against a load. Further, even if the user sits on the front end side of the seat body 18, even if a rotational moment in which the rear end rises with the front end side as a fulcrum occurs in the seat body 18, the slide shaft 22 can be used. Is engaged with the lower engaging recess 8b, so that the seat body 18 does not rotate in the upright direction. That is,
It can be used stably with the seat body 18 lying down. If the slide shaft 22 and the engaging recess 8b of the guide groove 8 are accidentally disengaged during use, the seat 1
When a large load is applied to the front end side of P8 as shown by P in FIGS. 1A and 2A, the seat body 18 may suddenly turn in the upright direction. However, since the step portion 8a whose lower side is deeper than the upper side is formed in the middle portion of the guide groove 8, the slide shaft 22 is attached to the step portion 8a.
a. Therefore, the rotation of the seat body 18 in the upright direction is achieved by the engagement of the slide shaft 22 with the step 8a.
As shown by the chain line in FIG. 2 (a), the user's hips are blocked in the state of being slightly inclined from the horizontal state. It is possible to prevent fingers or the like from being sandwiched between the front leg member 2 and the front leg member 3. The folding chair 1 is folded when not in use. In the case of folding, the slide shaft 22 is
After being disengaged from the lower engagement recess 8b by sliding in the immersion direction against the urging force of the above, the rear leg member 2 is rotated toward the front leg member 3 with the first connection point A as a fulcrum. As a result, the slide shaft 21, which slidably supports the rear end of the seat member 18 in the guide groove 8 of the rear leg member 2, slides upward from the lower end of the guide groove 8. Rotates in a direction toward the front side of the chair 1 whose upper surface is folded. When the slide shaft 21 slides to the upper end of the guide groove 8 and engages with the upper engagement recess 8c, the rear leg member 2 enters between the pair of second strips 11 of the front leg member 3, and As shown in FIG. 4, the front surface of the first band plate 4 abuts on the intermediate portion 14b of the connection fitting 14. As a result, the first leg member 2 and the second leg member 3 are folded flat with a minimum thickness. Further, at this time, the seat body 18 faces the front side of the chair 1 whose upper surface is folded. For example, if the back side of the chair 1 is leaned toward the wall surface side, the lower surface of the seat body 18 is It is not necessary to expose unsightly portions such as the back of the backrest 7 and the like, so that the appearance is good. Further, the slide shaft 22 is connected to the upper engaging recess 8.
By engaging with c, the folded state of the chair 1 is maintained, so that the rear leg member 2 and the front leg member 3 do not open during carrying or the like, and the seat body 18 does not fall down. Further, when the rear leg member 2 is rotated with respect to the front leg member 3 until the opening angle thereof becomes zero, a slide shaft 21 slidably supporting the rear end of the seat body 18 is provided.
A support point C, which is an axis of the first connection point, connects a first connection point A connecting the pair of leg members 2 and 3 to a connection point B connecting the lower surface of the front end of the seat body 18 to the front leg member 3. The straight line X is reversed from the back side to the front side. The reversal dimension is indicated by Z in FIG. When the support point C is inverted with respect to the straight line X, it is difficult to return to the opposite direction. That is, since there is a resistance at the time of inversion, it is difficult to return from the inverted state to the opposite direction due to the resistance. Therefore, the chair 1 in the folded state
Since the rear leg member 2 does not rotate with respect to the front leg member 3 unless a force equal to or greater than the resistance at the time of reversal is applied, this also allows the pair of leg members 2, There is no rattling when 3 opens. In the above-described embodiment, the band plates of the first and second leg members are formed of plywood, but instead of plywood, aluminum or stainless steel is used.
It may be formed of metal such as metal. According to the first aspect of the present invention, when the pair of leg members are closed, the seat body slides in the ascending direction at the rear end side with the front end side as a fulcrum. Since the upper surface of the seat body is on the front side and the lower surface is not exposed on the front side, the folded appearance is good. Further, when the seat body is used in an upside down state and when the seat body is not upright, the slide shafts are respectively inserted into a lower engaging recess formed at the lower end of the guide groove and an upper engaging recess formed at the upper part. for engaging said seat body inclined state and standing state when not in use at the time of use is securely held. This prevents the seat body from rotating in the upright direction during use, and prevents the pair of leg members from opening and the seat body from falling down when not in use. Further, a step is formed in the middle of the guide groove so that the lower side is deeper than the upper side. Therefore, for example, even when the guide shaft is inadvertently disengaged from the lower engagement concave portion during use and the seat body tries to rotate in the upright direction, the guide groove engages with the step portion, so that the seat body rapidly Is prevented from rotating in the upright direction.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1A and 1B show an embodiment of the present invention, wherein FIG. 1A is a perspective view of a used state, and FIG. 1B is a perspective view of a folded state. 2 (a) is a side view of the same use state, and FIG. 2 (b) is an explanatory view showing the movement when folding from the use state. 3A is a front view of the rear leg member, and FIG. 3B is a cross-sectional view of the rear leg member taken along line AA of FIG. 3A. FIG. 4 is a perspective view showing the lower surface side of the seat body. 5A is a perspective view of a portion of the rear leg member where a guide groove is formed, and FIG. 5B is a sectional view of the same. FIG. 6 is a partially broken perspective view of a bracket attached to the rear end of the lower surface of the seat body. [Description of Reference Numerals] 2 rear leg member 3 front leg member 8 guide groove 8a step 8b lower engaging recess 8c upper engaging recess 18 seat body 22 slide shaft 23 spring

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) A47C 4/04 A47C 5/10

Claims (1)

(1) A folding chair that can be folded flat when not in use, a rear leg member having an upper portion formed with a backrest and a lower portion formed on a rear leg, and the rear leg member. A guide groove having an upper engaging recess and a lower engaging recess formed at an upper end portion and a lower end portion thereof along a vertical direction in a middle portion, and a lower portion formed on a front leg and an upper portion formed on a front leg. A front leg member rotatably connected to an upper end portion of the rear leg member, a seat body having a front end side lower surface rotatably connected to a vertically intermediate portion of the front leg member, When the seat body is laid down in a state in which it is elastically urged in the axial direction toward the rear end of the lower surface and is slidably engaged with the guide groove and is urged in the axial direction, the lower engagement When it is engaged with the engagement recess and is standing, it engages with the upper engagement recess. A slide shaft for preventing rotation of the seat body, and a guide groove formed at a vertically intermediate portion of the guide groove.
With the lower side deeper than the upper side, and
The lower part of the slide shaft engages with the slide shaft due to the
When the engagement with the recess is released, the slide shaft engages
And a step for preventing the seat body from rotating in the upright direction .