An angle adjuster comprising: a support; a rotating shaft supported at one end of the support so as not to be rotatable; a winding and tightening member in pressure contact with an outer peripheral surface of the rotating shaft; and a rocking body having an attachment portion on one end, the attachment portion being connected to the rotating shaft via the winding and tightening member, wherein the winding and tightening member includes a winding and tightening member body in pressure contact with the rotating shaft, a winding and tightening portion having a substantially J shape, extending from the winding and tightening member body, and in pressure contact with the outer peripheral surface of the rotating shaft, and a support portion extending from a free end of the winding and tightening portion and connected to an attachment portion of the rocking body, a rotation of the rocking body in a forward rotation direction reduces a tightening force of the winding and tightening member to the outer peripheral surface of the rotating shaft and reduces a frictional force due to contact between the outer peripheral surface of the rotating shaft and an inner surface of the winding and tightening portion of the winding and tightening member, and thus the rotation of the rocking body in the forward rotation direction is allowed, a rotation of the rocking body in a reverse rotation direction increases the tightening force of the winding and tightening member to the outer peripheral surface of the rotating shaft and increases the frictional force due to the contact between the outer peripheral surface of the rotating shaft and the inner surface of the winding and tightening portion of the winding and tightening member, and thus the rotation of the rocking body in the reverse rotation direction is blocked, and when an overload is applied to the rocking body in the reverse rotation direction, an increase in the frictional force of the winding and tightening member to the outer peripheral surface of the rotating shaft is restricted, and the overload causes the winding and tightening member to slide on the outer peripheral surface of the rotating shaft and rotate, characterized in that a winding and tightening restraining shaft provided on the attachment portion of the rocking body abuts on a position restraining protrusion provided on the winding and tightening member body to restrain the rotation of the rocking body and restrict an increase in the frictional force of the winding and tightening member to the outer peripheral surface of the rotating shaft, and the overload causes the winding and tightening member to slide on the outer peripheral surface of the rotating shaft and rotate. a support; a rotating shaft supported at one end of the support so as not to be rotatable; a winding and tightening member in pressure contact with an outer peripheral surface of the rotating shaft; and a rocking body having an attachment portion on one end, the attachment portion being connected to the rotating shaft via the winding and tightening member, wherein the winding and tightening member includes a winding and tightening member body in pressure contact with the rotating shaft, a winding and tightening portion having a substantially J shape, extending from the winding and tightening member body, and in pressure contact with the outer peripheral surface of the rotating shaft, and a support portion extending from a free end of the winding and tightening portion and connected to an attachment portion of the rocking body, a rotation of the rocking body in a forward rotation direction reduces a tightening force of the winding and tightening member to the outer peripheral surface of the rotating shaft and reduces a frictional force due to contact between the outer peripheral surface of the rotating shaft and an inner surface of the winding and tightening portion of the winding and tightening member, and thus the rotation of the rocking body in the forward rotation direction is allowed, a rotation of the rocking body in a reverse rotation direction increases the tightening force of the winding and tightening member to the outer peripheral surface of the rotating shaft and increases the frictional force due to the contact between the outer peripheral surface of the rotating shaft and the inner surface of the winding and tightening portion of the winding and tightening member, and thus the rotation of the rocking body in the reverse rotation direction is blocked, and when an overload is applied to the rocking body in the reverse rotation direction, an increase in the frictional force of the winding and tightening member to the outer peripheral surface of the rotating shaft is restricted, and the overload causes the winding and tightening member to slide on the outer peripheral surface of the rotating shaft and rotate, characterized in that a winding and tightening restraining shaft provided on the attachment portion of the rocking body abuts on a position restraining protrusion provided on the winding and tightening member body to restrain the rotation of the rocking body and restrict an increase in the frictional force of the winding and tightening member to the outer peripheral surface of the rotating shaft, and the overload causes the winding and tightening member to slide on the outer peripheral surface of the rotating shaft and rotate.