The present invention is wrapped around in a row As a feature of the structure, at a predetermined interval in the longitudinal direction on the outer surface of the barrel relates to a heating device for heating the barrel of the injection machine, and a heating wire for heating the barrel to the inner structure, the inner surface the outer surface portion of the outer barrel and the communication path providing cooling grooves are arranged in a semicircle ring-shaped heat insulators in which the to; Thermal insulation board and the insulation, and the heat insulating cover attached to the outer surface of the insulating board, the hinge and the ring cicada to induce de-attached to the barrel on both sides engaging with each other wherein the insulating cover is bonded to fit the outer surface of the heat insulators composed of; One end of the heat insulator on the outer surface of the barrel is wrapped around to be sealed with the outside, is provided with a cooling booth which communicates with the cooling grooves in the inner surface, the is in communication with the cooling booth with the outer surface leading to joints connector is projected to cool the cover; It comprises; and a cooling pump to suck the fluid to be cooled barrel is connected to the cover and the cooling pipe.
In the present invention, it is not to by attaching a separate insulating cover or cooling device implements the functionality effects that the device itself can significantly improve the overall heat insulation and the cooling performance improves with a structure having a heat insulating and cooling along.