| 摘要 |
Provided is a cartridge type linear dental electric syringe wherein the advance drive of a push rod is attained by a simple mechanism by arranging in a straight line the drive shaft of a motor with a reduction gear (geared motor), serving as a prime mover, and the push rod. The cartridge type linear dental electric syringe comprises an externally-threaded push rod (32) arranged non-rotatably and movably in the longitudinal direction so as to be in line with the drive shaft of a motor with a reduction gear (geared motor) (28), a rotary tube (40) being rotated by the drive shaft, a nut (57) pivotally attached to the rotary tube and consisting of a pair of nut halves (56) that are in the shape of an arm and arranged opposite to each other and have internal threads (68) meshing with the external thread (34) of the push rod (32), a lock ring (70) arranged rotatably and movably, in the longitudinal direction, between a backward position where the internal thread of the nut half in the shape of an arm meshes with the external thread of the push rod and a front position where the meshing is released, a pusher pin (75) that is inserted into a cylindrical space (24) and pushed by the end face of a cartridge holder (22) that is coupled with the space (24) in order to move the lock ring (70) from the front position to the backward position, and a coil spring (80) for pushing the lock ring (70) back to the front position when the cartridge holder (22) is not inserted into the cylindrical space, wherein the nut (57) is rotated around the push rod (32) by the rotation of the rotary tube (40) and thereby the push rod (32) is advanced by a screw action. |
