Angle adjusting device for back plate of transfusion chair

The utility model discloses an angle adjusting device for a back plate of a transfusion chair. The angle adjusting device has an very simple and convenient adjusting mode and comprises the back plate, wherein the two sides of the lower end of the back plate are hinged with a seat bracket respectively; the seat bracket is provided with handrails; the tail part of a controllable air spring is hinged with the lower end of the back plate; the front end of a piston rod of the controllable air spring is fixedly connected with a wrench bracket; the wrench bracket is fixedly arranged at the bottom of the seat bracket; the wrench bracket is movably provided with a wrench; the wrench is connected with a driving device; the wrench can be pulled by the driving device to wrench towards one side of the controllable air spring, and a valve ejection rod on the end part of the piston rod is pushed to move towards the interior of the piston rod, so that an internal space of the controllable air spring is opened to unlock the l