chair

Abstract

When adjusting the front-rear angle of the backrest, the backrest frame is warped to prevent the lumbar from moving away from the user's waist, thereby enabling the entire backrest to support the user's weight, and dispersing the user's weight applied to the backrest, thereby improving the seating comfort. [Solution] To this end, the chair according to the present invention includes a backrest frame that supports the backrest, a back panel post to which the lower end of the backrest frame is hinged and which can rotate back and forth around the lower end as the center of rotation, a back panel slider that is connected to the back panel post above the hinge so that it can slide up and down, and a back panel connector that connects the backrest frame and the back panel slider, and the back panel connector moves the backrest frame in the direction in which the user's weight acts.

Description

[Technical Field]

[0001] The present invention relates to a chair, and more particularly to a chair with a backrest that can be tilted backward. [Background technology]

[0002] Generally, chairs with a reclining backrest allow the user to tilt the chair (adjusting the angle of the backrest) by leaning their back against the backrest after sitting in the chair.

[0003] Korean Patent Publication No. 10-1980343 (published on August 28, 2019) (hereinafter referred to as "Prior Art") discloses a "chair with improved lumbar support," which is a chair with a backrest that bends backward.

[0004] In the conventional technology, a back seat frame is provided as a support structure for the backrest, and a lumbar is provided in the back seat frame as a structure for supporting the user's lower back.

[0005] However, in the conventional technology, when a user leans their back against the backrest and tilts, the shape of the backrest does not change and they simply arch back. Therefore, when a user sits on a chair and tilts, even if they lean their back against the lumbar, the angle of their legs and buttocks remains the same and only their back moves.

[0006] In this case, the lower back is separated from the lumbar, creating a gap so that the lumbar cannot support the user's lower back, and only a part of the back comes into contact with the backrest, causing pressure to be applied only to the part of the back that comes into contact with the back. Summary of the Invention [Problem to be solved by the invention]

[0007] The technical object of the present invention is to provide a chair that can support the weight of the user with the entire backrest by bending the backrest frame when adjusting the front-to-back angle of the backrest to prevent the lumbar from moving away from the user's waist, thereby distributing the user's weight applied to the backrest and improving seating comfort.

[0008] Another technical object of the present invention is to provide a chair in which, when the backrest is bent backward, the lumbar cover applies a force downward so that the lumbar presses against the user's lower back.

[0009] Yet another technical object of the present invention is to provide a chair that allows the backrest to move when the user moves their body from side to side, so that the backboard and the user's body can move organically without separating.

[0010] The technical problems of the present invention are not limited to those mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description. [Means for solving the problem]

[0011] In order to achieve the above object, the chair of the present invention comprises a backrest frame, a backboard post, a backboard slider, and a backboard connector. The backrest frame supports the backrest. The lower end of the backrest frame is hingedly connected to the backboard post. The backboard post can rotate back and forth around the lower end as the center of rotation. The backboard slider is connected to the backboard post above the hinge so as to be slidable up and down. The backboard connector connects the backrest frame and the backboard slider. The backboard connector moves the backrest frame in the direction in which the user's weight acts.

[0012] The back plate connector may be made of a soft material that is deformable by the weight of the user.

[0013] A connector insertion portion may be protruded from the front surface of the back panel slider. The connector insertion portion may have an insertion space with an open front surface. The back panel connector may be composed of a connector ring, a rear connector, and a front connector. The connector ring may have a through-hole formed therethrough in the front and rear direction, into which a front end of the connector insertion portion is inserted. The rear end of the rear connector may be inserted into the insertion space. The front end of the rear connector may protrude forward of the connector insertion portion and be positioned within the through-hole. The front connector may be connectable to a front end of the connector ring. The front connector may be fastenable to a front end of the rear connector. The front connector may be fastenable to the backrest frame.

[0014] The front connector may have an insertion groove formed on a rear surface thereof into which a front end portion of the rear connector is inserted.

[0015] The back panel slider may have a first fastening hole passing through the center of the insertion space. A second fastening hole passing through the front and rear may be formed in the center of the front connector. A third fastening hole passing through the front and rear may be formed in the center of the rear connector. The third fastening hole may have a rear end with a larger diameter than the front end. The chair according to the present invention may further include a female fastening member and a male fastening member. The female fastening member may have a first head and a female stem. The first head may be able to contact the rear surface of the back panel slider. The female stem may be protruding from a front surface of the first head. The female stem may pass through the first fastening hole and be inserted into a rear end of the third fastening hole. The male fastening member may have a second head and a male stem. The second head may be able to contact the front surface of the front connector. The male stem may be protruding from a rear surface of the second head. The male stem may be inserted into the third fastening hole through the second fastening hole and fastened to the female stem.

[0016] A second head cover may be formed to protrude from the center of the front surface of the front connector and surround the second head.

[0017] A first flange to be inserted into the insertion groove may be formed to protrude in the radial direction on the outer peripheral surface of the front end of the rear connector. A second flange may be formed to protrude in the radial direction on the outer peripheral surface of the front end of the connector ring. A third flange insertion groove may be formed on the inner peripheral surface of the front end of the connector ring. A third flange may be formed to protrude in the radial direction on the outer peripheral surface of the rear end of the front connector. The third flange may be inserted into the third flange insertion groove.

[0018] The front connector may have a fourth fastening hole formed therethrough, passing through the front and rear of the front connector. A fastening member to be fastened to the backrest frame may pass through the fourth fastening hole. The rear connector may have a fastening groove formed on a front surface thereof. An end of the fastening member may be inserted into the fastening groove.

[0019] An insertion groove having a vertical length longer than the vertical length of the back plate slider may be formed on the front surface of the upper end of the back plate post. A slide coupling protrusion may be formed on the rear surface of the back plate slider. A slide coupling groove portion having a vertical length longer than the vertical length of the slide coupling protrusion and into which the slide coupling protrusion is inserted may be formed within the insertion groove of the back plate post. Slide protrusions may be formed on both left and right sides of the slide coupling protrusion, respectively, to be inserted into slide grooves formed on both left and right sides of the slide coupling groove portion and arranged to be vertically movable.

[0020] The backrest frame may include a backrest plate, a lumbar, and a lumbar cover. The back panel connector may be connectable to the backrest plate. The lumbar may be disposed on the front surface of the lower end of the backrest plate. The lumbar may support the user's lower back. The lumbar cover may be connectable to the rear surface of the lower end of the backrest plate. The lumbar cover may support the weight of the user's lower back applied to the lumbar. A hinge connection portion to be connected to the hinge may be protruded from the lower end of the lumbar cover at the center in the left-right direction.

[0021] The hinge coupling portion may be formed to protrude downward from a lower end of the backrest plate.

[0022] The hinge joint may be made of an elastic material.

[0023] The backrest plate may be made of an elastic material. The backrest plate may have a plurality of slits formed therein that run from front to back and are elongated in the left-right direction.

[0024] The backrest portion may further include a backrest cushion. The backrest cushion may be disposed in front of the backrest plate. The backrest cushion may have a cushioning force. The lumbar may be disposed between the backrest cushion and the backrest plate.

[0025] A plurality of stiffening ribs may be formed to protrude from the front surface of the upper end of the backrest plate above the lumbar.

[0026] When the user leans his / her back against the backrest and bends the backboard post backward, the backboard slider slides downward, and the backrest frame bends while rotating around the hinge as the center of rotation, so that the upper part moves backward and the lower part moves forward.

[0027] Further details of the embodiments are included in the detailed description and drawings. [Effects of the Invention]

[0028] When tilting (adjusting the backrest angle), the chair of the present invention has the effect of improving seating comfort by allowing the lumbar support part to move forward and fill the empty space between the back and the body, so that the entire body comes into contact with the backrest, dispersing the load and preventing localized pressure.

[0029] In addition, when the chair of the present invention is tilted, the back panel connector moves the backrest frame in the direction of the user's weight, so that the left and right sides of the backrest can always be attached to the user's back. This also has the effect of improving the seating comfort because the body moves together with the backrest when working or moving the body in the chair.

[0030] Furthermore, when the chair according to the present invention is tilted, the lumbar cover exerts a downward force depending on the angle of the backrest plate, and the lumbar presses against the user's lower back.

[0031] Furthermore, in the chair of the present invention, the backrest naturally descends and moves with the back when tilted, which has the effect of preventing clothes from rolling up due to friction with the backrest.

[0032] The effects of the present invention are not limited to those mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims. [Brief explanation of the drawings]

[0033] [Figure 1] 1 is a front perspective view of a chair according to an embodiment of the present invention; [Figure 2] FIG. 1 is a rear perspective view of a chair according to an embodiment of the present invention. [Figure 3] 1 is an exploded view of the main components of a chair according to an embodiment of the present invention. [Figure 4]FIG. 4 is a side cross-sectional view schematically showing the backrest portion shown in FIGS. 1 to 3. [Figure 5] FIG. 4 is a front perspective view showing the backrest frame and backboard post shown in FIGS. 1 to 3. [Figure 6] FIG. 4 is a rear perspective view showing the backrest frame and the backboard post shown in FIGS. 1 to 3. [Figure 7] FIG. 5 is a side view specifically showing the backrest frame shown in FIG. 4. [Figure 8] FIG. 10 is an exploded perspective view showing the upper end of the backer plate post, the backer plate slider, and the backer plate connector. [Figure 9] FIG. 9 is a rear perspective view of FIG. 8. [Figure 10] 10 is a side cross-sectional view showing the state in which the back frame is connected to the upper end of the back post by the back slider and the back connector. FIG. [Figure 11] FIG. 10 is an exploded perspective view showing the lower end of the backrest frame and the backboard post. [Figure 12] FIG. 12 is a rear perspective view of FIG. [Figure 13] FIG. 10 is a side cross-sectional view showing the state in which the lower end of the backrest frame is hinged to the backboard post. [Figure 14] 10A and 10B are diagrams showing the action when a user bends the backboard post backward while leaning their back against the backrest portion. DETAILED DESCRIPTION OF THE INVENTION

[0034] Hereinafter, a chair according to an embodiment of the present invention will be described with reference to the drawings.

[0035] FIG. 1 is a front perspective view showing a chair according to an embodiment of the present invention, and FIG. 2 is a rear perspective view showing a chair according to an embodiment of the present invention.

[0036] 1 and 2, a chair 1 according to an embodiment of the present invention may include a chair body 100, an adjustment device 200, legs 300, a backboard post 400, and armrests 510, 520.

[0037] The chair body 100 may include a seat portion 110, a backrest portion 120, and a headrest portion 130. The seat portion 110, the backrest portion 120, and the headrest portion 130 may be formed in a substantially rectangular shape.

[0038] The seat portion 110 can extend in the front and rear directions. The seat portion 110 can be a portion where a user sits. The seat portion 110 can support the user's buttocks and the thighs of each of the user's legs.

[0039] Of the upper surface of the seat 110, the rear portion, which supports the user's buttocks, may be formed to be slightly recessed downward, and the front portion, which supports the user's thighs, may be formed to be inclined so that it approaches the lower side as it goes forward.

[0040] The backrest 120 can extend vertically and can extend such that its lower end is located further forward than its upper end. The lower end of the backrest 120 can be connected to the backboard post 400 via a hinge (H, see FIG. 13). The hinge H can include a horizontal shaft (not shown) that is long in the left-right direction. The backrest 120 can also be formed as a separate structure from the seat 110.

[0041] The head receiving portion 130 can extend vertically. The head receiving portion 130 can be connected to the front upper end portion of the backrest portion 120. The head receiving portion 130 may be formed integrally with the backrest portion 120, or the lower end portion of the head receiving portion 130 may be connected to the front upper end portion of the backrest portion 120 so as to be rotatable about a horizontal shaft (not shown) that extends laterally.

[0042] The seat part 110 may include a seat cushion 111 and a seat plate 112. The seat cushion 111 may be disposed above the seat plate 112. The seat cushion 111 is made of a material having cushioning properties to provide a cushioned feeling to the user, and the seat plate 112 is made of a material harder than the seat cushion 111 to support the seat cushion 111.

[0043] The backrest 120 may be a portion that supports the back of the user. The backrest 120 may include a backrest cushion 121 and a backrest frame 122. The backrest cushion 121 may be disposed in front of the backrest frame 122. The backrest cushion 121 is made of a material having cushioning properties to provide a cushioned feeling to the user, and the backrest frame 122 is made of a material that is harder than the backrest cushion 121 to support the backrest cushion 121.

[0044] The back frame 122 can include a back plate 123, a lumbar (125, see FIGS. 4 and 5), and a lumbar cover 124.

[0045] The backrest plate 123 can support the weight of the user's back and waist. A back plate connector (700, see FIG. 3) described later can be connected to the rear surface of the backrest plate 123.

[0046] When a user sits on the chair 1, the lower end of the backrest plate 123 may be disposed opposite the user's waist. The lumbar 125 may be disposed on the front surface of the lower end of the backrest plate 123 to support the user's waist. The lumbar 125 may be formed in a plate shape with a concave front surface and a convex rear surface so as to surround the user's waist. The lumbar cover 124 may be coupled to the rear surface of the lower end of the backrest plate 123 to support the weight of the user's waist applied to the lumbar 125.

[0047] The head support portion 130 may be a portion that supports the head of the user. The head support portion 130 may include a head support cushion 131 and a head support plate 132. The head support cushion 131 may be disposed in front of the head support plate 132. The head support cushion 131 is made of a material having cushioning properties to provide a cushioned feeling to the user, and the head support plate 132 is made of a material that is harder than the head support cushion 131 to support the head support cushion 131.

[0048] The seat cushion 111, the backrest cushion 121 and the headrest cushion 131 may be made of the same material, and the seat plate 112, the backrest frame 122 and the headrest plate 132 may be made of the same material.

[0049] The seat plate 112 and the head support plate 132 are formed to be slightly flexible, and can be slightly deformed by the weight of a user sitting on the chair 1.

[0050] In particular, the backrest plate 123 is made of an elastic material and is elastically deformed by the weight of the user acting on the backrest portion 120, thereby improving the seating comfort of the user sitting on the chair 1.

[0051] The adjustment device 200 may be disposed under the seat 110. The adjustment device 200 can be coupled to the underside of the seat plate 112 of the seat 110. The adjustment device 200 can adjust the height of the chair body 100 and can also adjust the front-to-back angle of the backboard post 400.

[0052] The adjustment device 200 may include two levers 210 and 220 that are operated by a user. Of the two levers 210 and 220, the first lever 210 may be a lever that protrudes from the right side of the adjustment device 200 and adjusts the height of the chair body 100 by the user's operation, and the second lever 220 may be a lever that protrudes from the left side of the adjustment device 200 and adjusts the forward / backward angle of the backrest post 400 by the user's operation.

[0053] A cylinder device 350 for adjusting the height of the chair body 100 may be provided at the center of the leg 300. The cylinder device 350 may be arranged vertically. The cylinder device 350 may include a cylinder and a piston rod. The cylinder may be inserted into a hole formed vertically through the center of the leg 300 to be connected to the center of the leg 300, and the upper end of the piston rod may be connected to the adjustment device 200. When a user sits on the chair body 100 and pulls the first lever 210 upward, the piston rod is pulled out of the cylinder through a hole formed at the upper end of the cylinder and moves upward, thereby allowing the user to adjust the height of the chair body 100.

[0054] The leg 300 may be disposed below the adjustment device 200. The leg 300 may support the adjustment device 200. The leg 300 may include a plurality of leg bodies 310 arranged radially. In this embodiment, the plurality of leg bodies 310 is formed in five pieces, but it is also possible to form the plurality of leg bodies 310 in three pieces or more. A wheel 320 may be rotatably coupled to the end of each of the plurality of leg bodies 310.

[0055] The back plate post 400 can support the backrest portion 120. The upper portion of the back plate post 400 can extend vertically, and the lower portion of the back plate post 400 can be bent forward from the lower end of the upper portion of the back plate post 400 and extend forward. The upper end of the back plate post 400 can be located below the upper end of the backrest portion 120. The upper end of the back plate post 400 can be located below the upper end of the backrest plate 123. The left-right width of the back plate post 400 can be narrower than the left-right width of the backrest portion 120. The left-right width of the back plate post 400 can be narrower than the left-right width of the backrest plate 123. The upper portion of the back plate post 400 can be located opposite the left-right center of the backrest portion 120 on the rear surface of the backrest portion 120. The upper portion of the backboard post 400 may be disposed on the rear surface of the backrest plate 123, facing the center of the backrest plate 123 in the left-right direction.

[0056] The armrests 510, 520 can support the left and right arms of a user. The armrests 510, 520 can include a left armrest 510 that supports the user's left arm and a right armrest 520 that supports the user's right arm. The left armrest 510 and the right armrest 520 can be formed with the same structure.

[0057] The left armrest portion 510 may include a left armrest post 511 and a left armrest 512 .

[0058] The upper portion of the left armrest post 511 can extend vertically, and the lower portion of the left armrest post 511 can be bent to the right side from the upper lower end of the left armrest post 511 and extend to the right side. The lower end of the left armrest post 511 can be connected to the left side of the lower end portion of the backboard post 400.

[0059] The left armrest 512 may be a portion that substantially supports the user's left arm. A left pad, which is the topmost component of the left armrest 512, may come into contact with the user's left arm. A left rod may be coupled to the underside of the left pad of the left armrest 512. The left rod is inserted into the left armrest post 511 through a hole formed at the top end of the left armrest post 511, and the height can be adjusted by being pulled out or inserted into the left armrest post 511 by the user's operation. In addition, the left pad may be configured so that its front-to-back position can be adjusted with respect to the left rod.

[0060] The upper portion of the right armrest post 521 may extend vertically, and the lower portion of the right armrest post 521 may be bent to the left from the upper lower end of the right armrest post 521 and extend to the left. The lower end of the right armrest post 521 may be connected to the right side of the lower end portion of the backboard post 400.

[0061] The right armrest 522 may be a portion that substantially supports the user's right arm. A right pad, which is the topmost component of the right armrest 522, may come into contact with the user's right arm. A right rod may be coupled to the underside of the right pad of the right armrest 522. The right rod is inserted into the right armrest post 521 through a hole formed at the top end of the right armrest post 521, and the height can be adjusted by being pulled out or inserted into the right armrest post 521 by the user's operation. In addition, the right pad may be configured so that its front-to-rear position can be adjusted relative to the right rod.

[0062] FIG. 3 is an exploded view of the main components of a chair according to an embodiment of the present invention.

[0063] Referring to FIG. 3, the lower end of the back panel post 400 is arranged to be rotatable around a horizontal axis (not shown) that is long in the left-right direction, and the back panel post 400 can be tilted (adjusted in front-to-back angle) by rotating around the lower end.

[0064] That is, the adjustment device 200 may include a pair of tilting bridges 250 formed long in the front-to-rear direction, and the lower end of the back panel post 400 may be rotatably connected to the rear end of the tilting bridge 250 around a horizontal axis (not shown) as the rotation center, and the front end of the tilting bridge 250 may be connected to the adjustment device 200.

[0065] A hole may be formed at the rear end of the tilting bridge 250 to which the lower end of the back plate post 400 is rotatably coupled via a horizontal shaft (not shown) that is long in the left-right direction. Here, the hole may be formed long in the front-rear direction.

[0066] On the other hand, when a user sits on the chair 1 and leans his / her back against the backrest portion 120, the backrest frame 122 can bend backward while the backrest portion 120 remains in close contact with the user's back and waist.

[0067] For this purpose, the lower end of the backrest frame 122 can be connected to the back plate post 400 via a hinge (H, see Figure 13), and the upper end of the backrest frame 122 can be connected to the upper end of the back plate post 400 via a back plate slider 600 and a back plate connector 700.

[0068] The back plate slider 600 may be coupled to the back plate post 400 above the hinge H so as to be able to slide up and down, and the back plate connector 700 can connect the back plate slider 600 and the backrest frame 122 together.

[0069] When the user leans their back against the backrest 120 and bends the backboard post 400 backward, the backboard slider 600 can slide downward, causing the backrest frame 122 to bend while rotating around the hinge H, maintaining the upper and lower parts of the backrest 120 in close contact with the user's back and waist. At this time, the backboard connector 700 moves the backrest frame 122 in the direction in which the user's weight acts, maintaining the left and right sides of the backrest 120 in close contact with the user's back and waist.

[0070] In this way, it is preferable that the back panel connector 700 is formed of a soft material that can be deformed by the user's weight so that the back panel connector 700 can move the back panel frame 122 in the direction in which the user's weight acts when the user tilts the back panel 120. In other words, when the user tilts the back panel 120, the back panel connector 700 can deform by the user's weight and move the back panel frame 122 in the direction in which the user's weight acts.

[0071] The action when the user tilts the backrest 120 will be described in detail later with reference to Figure 14, and the detailed structures of the backrest frame 122, back panel slider 600 and back panel connector 700 will be described first below.

[0072] Figure 4 is a side cross-sectional view showing a schematic representation of the backrest portion shown in Figures 1 to 3, Figure 5 is a front oblique view showing the backrest frame and back panel post shown in Figures 1 to 3, Figure 6 is a rear oblique view showing the backrest frame and back panel post shown in Figures 1 to 3, and Figure 7 is a side view showing in detail the backrest frame shown in Figure 4.

[0073] 4 to 7, as described above, the backrest frame 122 can include the backrest plate 123, the lumbar 125, and the lumbar cover .

[0074] A backrest cushion 121 having cushioning force can be connected to the front surface of the backrest plate 123. The backplate connector 700 described above can be connected to the rear surface of the backrest plate 123. A fabric cover may be placed on the outside of the backplate plate 123, and the backplate plate 123 may be placed inside the fabric cover.

[0075] The lumbar cover 124 can be attached to the rear surface of the lower end of the backrest plate 123. A lumbar 125 for supporting the user's lower back can be attached to the front surface of the lumbar cover 124, and the lumbar 125 may be disposed on the front surface of the lower end of the backrest plate 123. The lumbar 125 is disposed between the backrest cushion 121 and the backrest plate 123 to support the user's lower back leaning against the backrest cushion 121. The lumbar 125 can be attached to the lumbar cover 124 through a hole formed in the lower end of the backrest plate 123. The lumbar cover 124 is attached to the rear surface of the lower end of the backrest plate 123 to support the weight of the user's lower back applied to the lumbar 125.

[0076] A hinge coupling part 127 to be coupled with a hinge (H, see FIG. 13) may be formed to protrude downward from the lower end of the center in the left-right direction of the lumbar cover 124. The hinge coupling part 127 may be formed to protrude downward from the lower end of the backrest plate 123. The hinge coupling part 127 is made of an elastic material and can be elastically deformed when the user tilts the backrest part 120.

[0077] A plurality of rigid reinforcing ribs 123A may be formed to protrude from the front surface of the upper end of the backrest plate 123. The plurality of rigid reinforcing ribs 123A may be formed in a portion of the front surface of the upper end of the backrest plate 123 above the lumbar 125. The lumbar 125 may be disposed in the front surface of the lower end of the backrest plate 123, which is a portion of the front surface of the backrest plate 123 where the plurality of rigid reinforcing ribs 123A are not formed.

[0078] The plurality of rigid reinforcing ribs 123A ensure that the backrest plate 123 has the strength to support the weight of the user's back and also ensure that the backrest plate 123 has the strength to bend elastically due to the weight of the user's back.

[0079] The multiple rigid reinforcing ribs 123A can include a circular rib formed in the center of the front surface of the backrest plate 123, a first arc-shaped rib surrounding the outside of the circular rib, a second arc-shaped rib surrounding the outside of the first arc-shaped rib, multiple lattice-shaped ribs formed across the entire front surface of the upper end of the backrest plate 123, and multiple linear ribs arranged radially to connect the circular rib, the first arc-shaped rib, the second arc-shaped rib, and the multiple lattice-shaped ribs.

[0080] The backrest plate 123 is made of an elastic material and can be elastically deformed when the user tilts the backrest portion 120. The backrest plate 123 has a plurality of slits 126 that run from front to back and are long in the left to right direction, so that the backrest plate 123 can be easily deformed by the weight of the user's back and waist.

[0081] Figure 8 is an exploded perspective view showing the upper end of the back panel post, the back panel slider, and the back panel connector, Figure 9 is a rear perspective view of Figure 8, and Figure 10 is a side cross-sectional view showing the backrest frame connected to the upper end of the back panel post by the back panel slider and the back panel connector.

[0082] 8 to 10, the back plate slider 600 can be coupled to the front surface of the upper end of the back plate post 400 so as to be slidable back and forth. An insertion groove 410 into which the back plate slider 600 is inserted may be formed on the front surface of the upper end of the back plate post 400. The vertical length of the insertion groove 410 may be longer than the vertical length of the back plate slider 600. The back plate slider 600 can slide up and down within a range from when the upper end of the back plate slider 600 contacts the upper side of the insertion groove 410 to when the lower end of the back plate slider 600 contacts the lower side of the insertion groove 410.

[0083] The back slider 600 may be formed in a rectangular shape that is long in the vertical direction. A slide coupling protrusion 615 may be formed to protrude from the rear surface of the back slider 600. The edge of the slide coupling protrusion 615 may be formed in a rectangular shape that is long in the horizontal direction, and a plurality of spaces may be formed inside the slide coupling protrusion 615.

[0084] A slide coupling groove 415 into which the slide coupling protrusion 615 is inserted may be formed in the insertion groove 410 of the back plate post 400. The vertical length of the slide coupling groove 415 may be longer than the vertical length of the slide coupling protrusion 615. The back plate slider 600 can move up and down within a range from when the upper end of the slide coupling protrusion 615 contacts the upper side of the slide coupling groove 415 to when the lower end of the slide coupling protrusion 615 contacts the lower side of the slide coupling groove 415.

[0085] Slide protrusions 616 and 617 may be formed on both the left and right sides of the slide coupling protrusion 615. The slide protrusions 616 and 617 may include a first slide protrusion 616 formed on the left side of the slide coupling protrusion 615 and a second slide protrusion 617 formed on the right side of the slide coupling protrusion 615. The first slide protrusions 616 may be formed in pair on the left side of the slide coupling protrusion 615, or at least one first slide protrusion 616 may be formed on the left side of the slide coupling protrusion 615. The second slide protrusions 617 may be formed in pair on the right side of the slide coupling protrusion 615, or at least one second slide protrusion 617 may be formed on the right side of the slide coupling protrusion 615.

[0086] It is preferable that slide grooves (not shown) are formed on both the left and right sides of the slide coupling groove portion 415, and the slide protrusions 616 and 617 are inserted into the slide grooves to be arranged to be movable up and down.

[0087] A connector insertion portion 620 may be formed to protrude from the front surface of the back plate slider 600. An insertion space 621 with an open front surface may be formed in the connector insertion portion 620. The connector insertion portion 620 may be formed in a cylindrical shape with an open front surface. The vertical cross section of the connector insertion portion 620 may be formed in an elliptical shape. However, the vertical cross section of the connector insertion portion 620 may be formed in a circular shape or a polygonal shape.

[0088] The back slider 600 may have a first fastening hole 622 formed therein, the first fastening hole 622 passing through the center of the insertion space 621 .

[0089] The backplate connector 700 may include a connector ring 710, a rear connector 720, and a front connector 730. The connector ring 710, the rear connector 720, and the front connector 730 may be formed in a shape corresponding to the connector insertion portion 620. That is, the vertical cross section of each of the connector ring 710, the rear connector 720, and the front connector 730 may be formed in an elliptical shape.

[0090] The connector ring 710 may have a through-hole 711 formed therethrough in the front-to-rear direction, into which the front end of the connector insertion portion 620 is inserted.

[0091] The rear end of the rear connector 720 may be inserted into the insertion space 621 of the connector insertion portion 620. The front end of the rear connector 720 may protrude forward of the connector insertion portion 620 and be disposed in the through-hole 711 of the connector ring 710.

[0092] The front connector 730 can be coupled to a front end of the connector ring 710. The front connector 730 can be fastened to a front end of the rear connector 720. An insertion groove 731 into which the front end of the rear connector 720 is inserted may be formed on the rear surface of the front connector 730.

[0093] A second fastening hole 732 passing through the front and rear may be formed in the center of the front connector 730. A third fastening hole 722 passing through the front and rear may be formed in the center of the rear connector 720. The third fastening hole 722 may be formed so that a rear end 722A has a larger diameter than a front end.

[0094] The connector ring 710, the rear connector 720, the front connector 730, and the back plate slider 600 can be fastened together via female fastening members 740 and male fastening members 750. That is, the back plate connector 700 can be fastened to the back plate slider 600 via the female fastening members 740 and the male fastening members 750.

[0095] The female fastening member 740 may have a first head 741 and a female stem 742. The first head 741 may contact the rear surface of the back plate slider 600. The female stem 742 may be formed to protrude from the front surface of the first head 741. The female stem 742 may pass through the first fastening hole 622 and be inserted into the rear end 722A of the third fastening hole 722.

[0096] The male fastening member 750 may have a second head 751 and a male stem 752. The second head 751 can contact the front surface of the front connector 730. The male stem 752 may be formed to protrude from the rear surface of the second head 751. The male stem 752 can be inserted through the second fastening hole 732 and into the third fastening hole 722 to fasten with the female stem 742.

[0097] The inner peripheral surface of the female stem portion 742 may be threaded, and the outer peripheral surface of the male stem portion 752 may be threaded to engage with the threads formed on the inner peripheral surface of the female stem portion 742.

[0098] The female stem portion 742 and the male stem portion 752 are fastenable within the rear end 722A of the third fastening hole 722.

[0099] A second head cover 733 may be formed to protrude from the center of the front of the front connector 730 and surround the second head 751. A second fastening hole 732 may be formed in the center of the internal space of the second head cover 733 so as to pass through the front and rear.

[0100] The inner peripheral surface of the second head cover 733 may be formed as a first curved surface that is concave rearward, and the rear surface of the second head 751 may be formed as a second curved surface that bulges rearward to match the first curved surface.

[0101] A first flange 725 may be formed on the outer peripheral surface of the front end of the rear connector 720 to protrude in the radial direction and be inserted into an insertion groove 731 formed on the rear surface of the front connector 730 .

[0102] A second flange 715 may be formed to protrude radially from the outer peripheral surface of the front end of the connector ring 710. A third flange insertion groove (716, see FIG. 10) may be formed in the inner peripheral surface of the front end of the connector ring 710.

[0103] A third flange 735 may be formed to protrude in the radial direction on the outer circumferential surface of the rear end of the front connector 730. The third flange 735 may be inserted into the third flange insertion groove 716.

[0104] The front connector 730 may have a fourth fastening hole 737 formed therethrough, passing through the front and rear. A fastening member (e.g., a bolt, not shown) for fastening to the backrest plate 123 of the backrest frame 122 may pass through the fourth fastening hole 737. A fastening groove 727 may be formed on the front surface of the rear connector 720. An end of the fastening member passing through the fourth fastening hole 737 may be inserted into the fastening groove 727. That is, the back plate connector 700 can be fastened to the backrest plate 123 of the backrest frame 122 via the fastening member.

[0105] The fourth fastening hole 737 may be disposed outside the second head cover 733. A plurality of fourth fastening holes 737 and a plurality of fastening grooves 727 may be provided, or in this embodiment, a pair of the fourth fastening holes 737 and a pair of the fastening holes 727 may be provided.

[0106] Figure 11 is an exploded perspective view showing the lower end of the backrest frame and the back panel post, Figure 12 is a rear perspective view of Figure 11, and Figure 13 is a side cross-sectional view showing the state in which the lower end of the backrest frame is hingedly connected to the back panel post.

[0107] 11 to 13, as described above, the lower end of the lumbar cover 124 may have a protruding hinge coupling portion 127 that is hinge-coupled to the back plate post 400 via a hinge H.

[0108] The hinge coupling portion 127 may be branched into two portions, including a left hinge coupling portion 127A disposed on the left side and a right hinge coupling portion 127B disposed on the right side.

[0109] A pair of first hinge protrusions 128 spaced apart from each other in the left-right direction may be formed on the rear surface of the lower end of the left hinge coupling part 127A. A first hinge hole 128A passing through in the left-right direction may be formed in each of the pair of first hinge protrusions 128.

[0110] A pair of second hinge protrusions 129 spaced apart from each other in the left-right direction may be formed on the rear surface of the lower end of the right hinge coupling part 127B. A second hinge hole 129A passing through in the left-right direction may be formed in each of the pair of second hinge protrusions 129.

[0111] A first hinge groove 420 into which the pair of first hinge protrusions 128 are inserted and a second hinge groove 430 into which the pair of second hinge protrusions 129 are inserted may be formed on the front surface of the back plate post 400. The first hinge groove 420 and the second hinge groove 430 may be arranged on the left and right.

[0112] A first insertion protrusion 421 may be formed in the first hinge groove 420 and inserted between the pair of first hinge protrusions 128. First coupling protrusions 422 may be formed on left and right sides of the first insertion protrusion 421 and inserted into first hinge holes 128A formed in each of the pair of first hinge protrusions 128, respectively, and rotatably coupled to the pair of first hinge protrusions 128.

[0113] A second insertion protrusion 431 may be formed in the second hinge groove 430 and inserted between the pair of second hinge protrusions 129. Second coupling protrusions 432 may be formed on left and right sides of the second insertion protrusion 431 and inserted into second hinge holes 129A formed in the pair of second hinge protrusions 129, respectively, and rotatably coupled to the pair of second hinge protrusions 129.

[0114] The pair of first hinge protrusions 128, the pair of second hinge protrusions 129, the first coupling protrusions 422 formed on both the left and right sides of the first insertion protrusion 421, and the second coupling protrusions 432 formed on both the left and right sides of the second insertion protrusion 431 may be substantially configured to be hinge-H coupled.

[0115] The operation of the chair according to the embodiment of the present invention configured as above will be explained as follows.

[0116] FIG. 14 is a diagram showing the action when the user bends the backboard post backward while leaning his / her back against the backrest portion.

[0117] 13 and 14, when a user leans their back against the backrest 120 and bends the backboard post 400 backward, the backboard slider 600 slides downward, and the backrest frame 122 bends while rotating around the hinge H, with the upper portion moving backward and the lower portion moving forward. Therefore, the user's back can be kept in close contact with the upper portion of the backrest 120, and the user's waist can also be kept in close contact with the lower portion of the backrest 120.

[0118] Furthermore, when the user leans their back against the backrest 120 and bends the backboard post 400 backward, the backboard connector 700 is deformed by the load acting on the backboard connector 700, and moves the backrest frame 122 in the direction of the load of the user. Therefore, the left and right sides of the backrest 120 can be kept in close contact with the back of the user.

[0119] In this way, when the chair 1 according to the embodiment of the present invention is tilted (adjusting the front and rear angle of the backrest), the lower part of the backrest 120, which is the lumbar support part, moves forward to fill the empty space between the back and the waist, and the entire body comes into contact with the backrest 120, dispersing the load and preventing localized pressure, thereby improving the sitting comfort.

[0120] In addition, when the chair 1 according to the embodiment of the present invention is tilted, the back panel connector 700 moves the back frame 122 in the direction in which the user's weight acts, so that the left and right sides of the back 120 can always be attached to the user's back. When working or moving the body in the chair, the body moves together with the back 120, improving the sitting comfort.

[0121] In addition, when the chair 1 according to the embodiment of the present invention is tilted, the lumbar cover 124 applies a force downward depending on the angle of the backrest plate 123, and the lumbar 125 can press the user's lower back.

[0122] Furthermore, in the chair 1 according to the embodiment of the present invention, the backrest 120 naturally descends and moves together with the chair when tilting, so that it is possible to prevent clothes from rolling up due to friction with the backrest 120.

[0123] Those skilled in the art will understand that the present invention can be embodied in other specific forms without changing the technical spirit or essential characteristics thereof. Therefore, the above-described embodiments should be understood to be illustrative in all respects and not limiting. The scope of the present invention is defined by the claims that follow rather than the above detailed description, and all modifications and variations that fall within the meaning and scope of the claims and their equivalents should be construed as being within the scope of the present invention. [Industrial Applicability]

[0124] To provide a chair capable of supporting the weight of a user with the entire backrest by preventing the lumbar from moving away from the user's waist by bending the backrest frame when adjusting the front-rear angle of the backrest, and distributing the weight of the user applied to the backrest to improve the sitting comfort. [Explanation of symbols]

[0125] 120 Backrest 121 Backrest Cushion 122 Backrest frame 123 Backrest Plate 123A Rigid reinforcement rib 124 Lumbar Cover 125 Lumber 126 Slit 127 Hinge joint 400 Backboard Post 410 Insertion groove 415 Slide coupling groove 600 Backboard Slider 615 Slide joint protrusion 616 Slide protrusion 620 Connector insertion part 621 Insertion Space 622 First Closing Hole 700 Backplate Connector 710 Connector Ring 711 Through Hole 715 Second flange 716 Third flange insertion groove 720 rear connector 722 3rd Concluding Hole 725 First flange 727 Fastening groove 730 Front Connector 731 Insertion groove 732 2nd Closing Hole 733 Second head cover 735 Third flange 737 4th Closing Hole 740 Female fastening member 741 Head 1 742 Female stem 750 Male fastener 751 2nd head 752 Male stem H hinge

Claims

1. a backrest frame that supports the backrest; a back panel post to which a lower end of the backrest frame is hinged and which can rotate back and forth around the lower end as a rotation center; a back plate slider coupled to the back plate post above the hinge so as to be slidable up and down; a back panel connector that connects the backrest frame and the back panel slider, The back panel connector moves the backrest frame in a direction in which the load of the user acts, A connector insertion portion having an insertion space with an open front surface is protruded from the front surface of the back slider, The backplate connector is a connector ring having a through hole formed therethrough in the front-rear direction, into which the front end of the connector insertion portion is inserted; a rear connector having a rear end inserted into the insertion space and a front end protruding forward of the connector insertion portion and disposed within the through-hole; a front connector coupled to a front end of the connector ring, fastened to a front end of the rear connector, and fastened to the backrest frame.

2. The chair of claim 1 , wherein the back panel connector is formed of a soft material that is deformable under the load of the user.

3. The chair according to claim 1, wherein an insertion groove into which a front end of the rear connector is inserted is formed on a rear surface of the front connector.

4. The back plate slider has a first fastening hole passing through the center of the insertion space, A second fastening hole is formed at the center of the front connector, passing through the front and rear. A third fastening hole is formed at the center of the rear connector, passing through the front and rear. The third fastening hole has a rear end with a larger diameter than a front end, a female fastening member having a first head portion contacting a rear surface of the back plate slider, and a female stem portion protruding from a front surface of the first head portion, passing through the first fastening hole, and inserted into a rear end portion of the third fastening hole; 4. The chair of claim 3, further comprising: a male fastening member having a second head that contacts the front surface of the front connector; and a male stem portion that protrudes from the rear surface of the second head, passes through the second fastening hole, and is inserted into the third fastening hole to fasten with the female stem portion.

5. The chair according to claim 4, wherein a second head cover surrounding the second head portion is formed to protrude from the center of the front surface of the front connector.

6. a first flange to be inserted into the insertion groove is formed on the outer peripheral surface of the front end of the rear connector and protrudes in the radial direction; A second flange is formed on the outer peripheral surface of the front end of the connector ring so as to protrude in the radial direction, and a third flange insertion groove is formed on the inner peripheral surface of the front end of the connector ring, The chair according to claim 4, wherein a third flange to be inserted into the third flange insertion groove is formed on the outer peripheral surface of the rear end of the front connector so as to protrude in the radial direction.

7. The front connector has a fourth fastening hole formed therein, through which a fastening member to be fastened to the backrest frame passes, the fourth fastening hole being formed in the front and rear directions. The chair according to claim 4, wherein a fastening groove into which an end of the fastening member is inserted is formed on a front surface of the rear connector.

8. An insertion groove having a vertical length longer than the vertical length of the back plate slider is formed on the front surface of the upper end of the back plate post, A slide coupling protrusion is formed on the rear surface of the back slider, A slide coupling groove portion having a vertical length longer than the vertical length of the slide coupling protrusion portion and into which the slide coupling protrusion portion is inserted is formed within the insertion groove of the back plate post, The chair according to claim 1, wherein a slide protrusion is formed on each of the left and right sides of the slide coupling protrusion portion, and is inserted into a slide groove formed on each of the left and right sides of the slide coupling groove portion, and is arranged to be movable up and down.

9. A backrest frame that supports the backrest; a back panel post to which a lower end of the backrest frame is hinged and which can rotate back and forth around the lower end as a rotation center; a back plate slider coupled to the back plate post above the hinge so as to be slidable up and down; a back panel connector that connects the backrest frame and the back panel slider, The back panel connector moves the backrest frame in a direction in which the load of the user acts, The backrest frame is a backrest plate to which the backplate connector is coupled; a lumbar support member disposed in front of the lower end of the backrest plate and supporting the user's lower back; a lumbar cover coupled to a rear surface of a lower end of the backrest plate to support a load of the user's lower back applied to the lumbar; The lumbar cover has a hinge joint portion protruding from a lower end of the center in the left-right direction thereof, to be hinged.

10. The chair according to claim 9, wherein the hinge joint is made of an elastic material and protrudes downward from the lower end of the backrest plate.

11. The backrest plate is formed of an elastic material, The chair according to claim 9, wherein the backrest plate is formed with a plurality of slits that run from front to back and are elongated in the left-right direction.

12. The backrest portion further includes a backrest cushion disposed on a front surface of the backrest plate and having a cushioning force; 10. The chair of claim 9, wherein the lumbar is disposed between the back cushion and the back plate.

13. 10. The chair according to claim 9, wherein a plurality of rigid reinforcing ribs are formed to protrude from the front surface of the upper end of the backrest plate above the lumbar.

14. 2. The chair according to claim 1, wherein when the user leans their back against the backrest portion and bends the backboard post backward, the backboard slider slides downward, causing the backrest frame to bend while rotating around the hinge as a center of rotation, with the upper portion moving backward and the lower portion moving forward.