Retractable Footrest for Chair

A chair comprising:

• a base;
• a seat disposed above the base, wherein the seat includes a first pivotal portion at a rear end thereof, wherein a first shaft is pivotably connected to the first pivotal portion and includes a first connecting portion and a second connecting portion, wherein the seat further includes a third connecting portion, and wherein the seat further includes a front end having two sides each having a fourth connecting portion;
• a backrest connected to the rear end of the seat;
• an operating unit including a transmission member, a spring, and a first motor, wherein an end of the transmission member is connected to the first connecting portion of the seat, wherein an end of the spring is connected to another end of the transmission member, wherein another end of the spring is connected to the third connecting portion, wherein the first motor is disposed on the seat and has an end connected to the second connecting portion;
• a footrest pivotably connected to the front end of the seat, wherein the footrest incudes a second shaft interlocked with the transmission member, wherein the first motor is operable in a direction to cause pivotal movement of the first shaft and to displace the transmission member to cause pivotal movement of the second shaft while stretching the spring, thereby moving the footrest to an extended position, and wherein the first motor is operable in a reverse direction to move the first shaft, the transmission member, and the second shaft in a reverse direction, and the footrest is returned to a retracted position under a returning force of the spring.