MASSAGE UNIT FOR A BACKREST, INCLUDING A BACKREST OF A CHAIR AND A PORTABLE BACKREST
A massage unit wherein at least some of the massage heads are pivotally moveable in an arc about an axis in a plane generally parallel to the front face of the massage unit and the massage heads are independently moveable in a direction generally perpendicular to the front face.
1 . A massage unit comprising:
(a) a front face;
(b) an arm pivotally mounted about an axis defined by a driveshaft, the arm pivotal in an arc about the axis in a plane generally parallel to the front face;
(c) at least one massage head mounted to the arm;
(d) a motor drivingly coupled to the arm;
(e) the draft shaft is rotatably mounted to the massage unit and moveable in a direction generally perpendicular to the front face; and,
(f) a depth adjustment motor drivingly coupled to the driveshaft.
2 . The massage unit of claim 1 , wherein the front face has an opening through which the massage head extends and rotation of the driveshaft in one direction moves the massage head outwardly with respect to the opening.
3 . The massage unit of claim 1 , further comprising another massage head mounted to the arm.
4 . The massage unit of claim 3 , wherein the arm has a midpoint, the arm is rotatably mounted on the driveshaft at the midpoint and a massage head is provided at opposed ends of the arm.
5 . The massage unit of claim 1 , wherein the massage unit comprises a plurality of arms, a plurality of driveshafts, and a plurality of depth adjustment motors, each of the arms is rotatably mounted on one of the driveshafts, and each of the driveshafts is drivenly coupled to one of the depth adjustment motors.
6 . The massage unit of claim 5 , wherein each arm is independently movable in a direction generally perpendicular to the front face.
7 . The massage unit of claim 1 , further comprising a speed reduction gear driven by the depth adjustment motor and having an inner threaded opening, and the driveshaft has a mating threaded outer surface that is rotatably received in the inner threaded opening of the speed reduction gear.
8 . The massage unit of claim 1 , further comprising a plurality of speed reduction gears provided between the driveshaft and the depth adjustment motor.
9 . The massage unit of claim 1 , wherein the depth adjustment motor is secured at a fixed location to the massage unit.
10 . The massage unit of claim 1 , wherein the motor coupled to the arm to move the arm in the plane substantially parallel to the back of the user causes to arm to oscillate.
11 . The massage unit of claim 1 , wherein the massage unit is built into a chairback of a chair.
12 . The massage unit of claim 1 , wherein the massage unit is portable and is adapted to be mounted on a chair back of a chair.