US 12,226,027 B2
Unit chair
Sang Yong Park, Goyang-si (KR)
Assigned to OSSTEMIMPLANT CO., LTD., Seoul (KR)
Appl. No. 17/761,266
Filed by OSSTEMIMPLANT CO., LTD., Seoul (KR)
PCT Filed Sep. 11, 2020, PCT No. PCT/KR2020/012344
§ 371(c)(1), (2) Date Mar. 17, 2022,
PCT Pub. No. WO2021/054685, PCT Pub. Date Mar. 25, 2021.
Claims priority of application No. 10-2019-0114189 (KR), filed on Sep. 17, 2019; application No. 10-2019-0114205 (KR), filed on Sep. 17, 2019; and application No. 10-2019-0114225 (KR), filed on Sep. 17, 2019.
Prior Publication US 2022/0370277 A1, Nov. 24, 2022
Int. Cl. A47C 7/38 (2006.01); A47C 1/00 (2006.01); A61G 15/02 (2006.01); A61G 15/12 (2006.01)
CPC A47C 7/38 (2013.01) [A47C 1/00 (2013.01); A61G 15/02 (2013.01); A61G 15/125 (2013.01)] 42 Claims
OG exemplary drawing
 
1. A unit chair comprising a link unit for adjusting a posture of a headrest, wherein the link unit includes:
a first link member fixed to a backrest portion of the unit chair;
a second link member having one end portion hinged to the first link member by a first hinge pin; and
a first ratchet member formed on one surface of at least one of the first link member and the second link member and constraining motion of the second link member so that the second link member is rotatable only in one direction about a central axis line of the first hinge pin,
wherein the first ratchet member includes
a first ratchet base portion including a plurality of saw teeth formed on one surface, the plurality of saw teeth arranged in a ring shape centered on the central axis line of the first hinge pin, protruding in a direction parallel to the central axis line, and inclined only in one rotational direction, and the ratchet base portion having an opposite surface fixed to the first link member; and
a first ratchet rotating portion including a plurality of saw teeth formed on one surface and at least partially engaged with at least some of the saw teeth of the first ratchet base portion and having an opposite surface fixed to the second link member, wherein
the second link member includes a first release portion transmitting an external force to the first ratchet member to release the motion constraint state of the second link member, and
wherein the first release portion includes:
a first button protruding from an external side surface of the second link member and receiving an external force applied thereto; and
a first operating member formed inside the second link member and supported by a first elastic member, having one surface to which the first button and the first ratchet rotating portion are fixed, and integrally moving together with the first button and the first ratchet rotating portion to separate the first ratchet rotating portion from the first ratchet base portion when an external force is applied to the first button.