Abstract: A lifting structure for an armrest mounted on a left side or a right side of a chair contains: an accommodation sleeve, a fixer, a swing arm retained in one of multiple recesses of the fixer via a slidable seat, an extension located between two drive members of the swing arm and accommodated inside a receiving tab of the slidable seat, and a connection plate covered on the accommodation sleeve so that the fixer is connected with a holder, and the connection plate is coupled with an armrest seat, thus connecting the armrest. The accommodation sleeve includes two concave seats. The fixer includes a groove and two closed slots. The slidable seat includes the receiving tab, two ribs extending, two cutouts, and two elongated orifices. The swing arm includes a coupling rod, an oblique hole, a locking projection, a column, and an indentation.

Abstract: An adjustable lifting structure for a chair back contains: a first adjustment unit and a second adjustment unit. The first adjustment unit mates with the second adjustment unit via a transmission cable, and the first adjustment unit includes a longitudinally hollow chamber for slidably accommodating a guide plate connected on a seat. The first adjustment unit includes a body and two covering assemblies. A drive block includes a locking space, a slit, two deformable chambers, a trough, and two projections. The guide plate includes a conducting element and a rail having multiple teeth and multiple cutouts. The second adjustment unit includes an adjuster, an operation cavity, a first aperture, a connecting room, and two stop segments. A transmission cable includes a first transmitting segment and a second transmitting segment, wherein the first transmitting segment has a first defining portion, and the second transmitting segment has a second defining portion.

Abstract: An adjustable lifting structure for a chair back contains: a first adjustment unit and a second adjustment unit. The first adjustment unit mates with the second adjustment unit via a transmission cable, and the first adjustment unit includes a longitudinally hollow chamber for slidably accommodating a guide plate connected on a seat. The first adjustment unit includes a body and two covering assemblies. A drive block includes a locking space, a slit, two deformable chambers, a trough, and two projections. The guide plate includes a conducting element and a rail having multiple teeth and multiple cutouts. The second adjustment unit includes an adjuster, an operation cavity, a first aperture, a connecting room, and two stop segments. A transmission cable includes a first transmitting segment and a second transmitting segment, wherein the first transmitting segment has a first defining portion, and the second transmitting segment has a second defining portion.

Abstract: A rotating device for an armrest is connected with a fixing mount disc on a top surface of an armrest seat and is rotatably coupled with a rotary plate on a bottom surface of the support plate. The fixing mount disc includes a conical groove and a threaded orifice formed on the conical groove, and the conical groove has a toothed slot. The rotary plate includes a post corresponding to the conical groove and the toothed slot, the rotary plate also includes an extending fringe extending outwardly from an outer side thereof to contact with a peripheral side of the fixing mount disc, wherein the post has two recesses, each recess extends outwardly from each of two sides of the post to accommodate each of two slidable retainers, and each slidable retainer is pushed by a spring and has a locking tab for retaining with the toothed slot.

Abstract: A rotating device for an armrest is connected with a fixing mount disc on a top surface of an armrest seat and is rotatably coupled with a rotary plate on a bottom surface of the support plate. The fixing mount disc includes a conical groove and a threaded orifice formed on the conical groove, and the conical groove has a toothed slot. The rotary plate includes a post corresponding to the conical groove and the toothed slot, the rotary plate also includes an extending fringe extending outwardly from an outer side thereof to contact with a peripheral side of the fixing mount disc, wherein the post has two recesses, each recess extends outwardly from each of two sides of the post to accommodate each of two slidable retainers, and each slidable retainer is pushed by a spring and has a locking tab for retaining with the toothed slot.

Abstract: A booster structure of legs contains a support plate including four posts disposed at four corners of a bottom end thereof respectively. Each post includes a plurality of recesses having a vertical sliding section and a number of horizontal retaining sections perpendicular to the vertical sliding section. Each of a plurality of vertical moving units, including includes an inner stem and an outer stem, with the outer stem including a bottom cover. A bolt element is inserted and slides between the inner and outer stems. The bolt element includes a straight sliding section and a number of engaging sections perpendicular to the straight sliding section and includes a resilient element, a button, and a lip. The button is disposed on one side of the outer stem so that the bolt element is forced by the button to slide horizontally and return to its original position.

Abstract: A pillow support structure of a chair contains a fixing unit including a body and a back cover, wherein the body includes a longitudinal groove having a laterally through slot and a limiting piece with a tilted guide recess and a defining end; the longitudinal groove includes a resilient swinging rib with a tooth portion and an abutting tab; a vertical moving unit including a moving member and a sliding panel having a stop element, a plurality of peripheral teeth, and includes a side rim biased against the abutting tab; an inserting member including a biasing end and a pressing segment, such that the stop element of the sliding panel of the moving member is capable of preventing from contacting with the defining end of the body so that the sliding panel of the moving member disengages from the body smoothly.

Abstract: A pillow support structure of a chair contains a fixing unit including a body and a back cover, wherein the body includes a longitudinal groove having a laterally through slot and a limiting piece with a tilted guide recess and a defining end; the longitudinal groove includes a resilient swinging rib with a tooth portion and an abutting tab; a vertical moving unit including a moving member and a sliding panel having a stop element, a plurality of peripheral teeth, and includes a side rim biased against the abutting tab; an inserting member including a biasing end and a pressing segment, such that the stop element of the sliding panel of the moving member is capable of preventing from contacting with the defining end of the body so that the sliding panel of the moving member disengages from the body smoothly.

Abstract: A booster structure of legs contains a support plate including four posts disposed at four corners of a bottom end thereof respectively, wherein each post includes a plurality of recesses having a vertical sliding section and a number of horizontal retaining sections perpendicular to the vertical sliding section; a plurality of vertical moving units, each including an inner stem and an outer stem, the outer stem including a bottom cover, the bolt element being inserted and sliding between the inner and the outer stems, and the bolt element including a straight sliding section and a number of engaging sections perpendicular to the straight sliding section, the bolt element including a resilient element, a button, and a lip, the button is disposed on one side of the outer stem so that the bolt element is forced by the button to slide horizontally and return its original position.