An adjustment mechanism for armrests which disposed on top of an armrest support comprising:
- an armrest plane, a lower plate, a base, a removable block, a rectangular piece, a disc, a locating ring as well as a corresponding elastic member, a locating pin and a corresponding elastic member, wherein the armrest plane is fastened with the lower plate so as to form a rectangular space between the armrest plane and the lower plate for accommodation of adjustment members;
- the lower plate having two linear locating slots, formed by a plurality of curved slots, symmetrically mounted on right and left sides on one end of an inner part thereof;
- the removable block is mounted inside the lower plate and with length shorter than the length of the inner part of the lower plate;
- two symmetrical slots are arranged on right and left sides of one end of the removable block for accommodation of a locating ring as well as an elastic member that presses the locating ring;
- the slots correspond to the locating slots of the lower plate so that the removable block slides forward and backward inside the lower plate and the removable block is located by the locating ring elastically mounting into one of the curved slots of the locating slots;
- a rectangular slot is set near a middle part of the removable block while a transverse slot is disposed near the middle part inside the rectangular slot and a slot is set on one side of the rectangular slot for accommodating a locating ring as well as an elastic member that presses the locating ring so that the locating ring presses elastically toward an inner part of the rectangular slot;
- the rectangular piece whose width is smaller than the width of an inner part of the rectangular slot is mounted inside the rectangular slot of the removable block;
- a plurality of curved slots, corresponding to the slot of the removable block, is arranged linearly on one side of the rectangular piece so that the rectangular piece is located inside the rectangular slot by the locating ring inside the slot elastically matching one of the curved slots while sliding transversely therein;
- a round slot with a central hole on the bottom thereof is disposed near a middle part of the rectangular piece;
- a slot is disposed on circumference of the round slot for accommodating a locating pin and an elastic member that presses the locating pin so that the locating pin elastically presses an inner part of the round slot;
- the disc is assembled inside the round slot of the rectangular piece;
- a step-like collar is formed on bottom of the disc, corresponding to and assembling with the central hole on bottom of the round slot;
- a rectangular hole is arranged on a bottom of the collar, corresponding to and secured with a fastening seat on the base;
- a plurality of locating slots corresponding to the slot of the rectangular piece is disposed on circumference of the disc so that while rotating inside the round slot, the disc is located by the locating pin inside the slot elastically matching with the locating slot;
- by a fastening member inserting through a central hole on the disc, the rectangular piece, and the transverse slot on bottom of the removable block, the disc is secured on a fastening hole of the fastening seat of the base;
- the base attaches on the bottom of the lower plate and having a fastening seat and a fastening hole on the fastening seat for securing the disc with the base while a lock hole is respectively arranged on two sides of the base for fastening the base with the armrest support;
- thereby, the armrest plane is fastened with the lower plate to form an armrest while the disc, the base and the armrest support are integrated with one another;
- wherein the lower plate slides forwards and backwards, relative to the removable block, the removable block is able to move transversely, relative to the rectangular piece and the rectangular piece rotates in a certain angle relative to the disc so that rotation angle, longitudinal displacement and transverse displacement of the armrest is adjustable.