JPH0436898Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention is used in the field of plastic molding machinery and equipment, and relates to the structure of a hot chip nozzle with an electric heater.

[Conventional technology]

Previous nozzles had an extremely simple assembly in which heating was achieved by spirally wrapping a capillary heater around the side of the nozzle. Since the thin tube heater is simply wrapped around the nozzle, there are some areas where the heat conduction to the nozzle is insufficient, and the thin tube heater in those areas does not dissipate heat sufficiently, causing overheating, disconnection, and rapid oxidation corrosion. etc. occur frequently, and the lifespan of the tube heater is short, making it impossible to fully expect stable work efficiency.Furthermore, since the tube heater is often fixed to the outer circumferential surface of the nozzle by welding, etc., the failure of the heater is a problem. In some cases, replacement of the cause required repair and replacement along with the nozzle, resulting in high parts replacement costs.

[Problem that the invention attempts to solve]

As mentioned above, simply wrapping the heater around the nozzle will not provide stable heat conduction and will not be able to withstand long-term use.Also, if the thin tube heater is wrapped around the outer circumference of the nozzle and fixed by welding, the heater will fail. Therefore, we aim to provide a nozzle that eliminates these factors as much as possible by eliminating such factors as poor heat radiation, poor heat resistance, extreme thermal oxidation corrosion, etc. of the thin tube heater. The problem is that it can be eliminated and maintained freely.

[Means to try to solve problems]

In order to solve such problems, conventionally the nozzle was heated by wrapping a thin tube heater around the outer circumferential surface of the hot chip nozzle in a coil shape and fixing it by metal welding etc., but in this application, the nozzle is heated by Instead of simply winding (not shown), which is the cause of the problem, the outer peripheral surface forms a male tapered part, a slotted part for tightening is formed on the side wall, and a tightening screw part is formed at the end of the side wall. An electric heating element is embedded inside a cylindrical fitting that is inserted into the hot chip nozzle and fixed therein, and a cylindrical good heat conductive member that has a female tapered inner surface that is inserted into the male tapered part. A heat-generating part whose surface is made of a heat-resistant material having poorer heat conductivity than the heat-conducting member, and a heat-generating part formed of a pair of assembled bodies, and configured to be attached to and detachable from the nozzle using a tightening fitting, and to be attached to the nozzle. Close fixation or replacement is extremely easy and flexible, making these arrangements a solution to such problems.

[Example of idea]

1 to 4 are cross-sectional views of one embodiment of the present invention. FIG. 1 is a side sectional view of the tip of the hot chip nozzle 1. FIG. In the conventional case, a thin tube heater is coiled around the outer peripheral surface of the side wall of the nozzle 1 and fixed by metal welding (not shown) to directly heat the nozzle 1. FIG. 2 is a side sectional view of the fitting 2 for mounting the heat generating part 3 on the nozzle 1. The cylindrical mounting fitting 2 has a male tapered part 2a formed on the outer peripheral surface of the side wall, a slot 2b formed in the side wall, and a tightening screw part 2c formed at the end of the side wall. The female tapered part 3d of the heat generating part 3 is inserted into the mounting bracket 2, and the heat generating part 3 forms a pair of assembled bodies by tightening the fastener nut 4. FIG. 3 is a side sectional view of the heat generating section 3. FIG.

The heat generating part 3 is covered with an exterior part 3a made of a heat-resistant material with low thermal conductivity to make it difficult to conduct the heat of the electric heat generating element 3b to the outside, and a member 3c in which the heat generating element 3b is buried. is a material that is a better heat conductor than the exterior part 3a and is softer than the material of the mounting fitting 2, and due to thermal expansion, it is brought into close contact with the outside part 3a to improve heat conduction. FIG. 4 is a side sectional view of the tightening metal fitting 4 nut. When the above-mentioned pair of assembled bodies inserted into the nozzle 1 are further tightened by the tightening screw part 2c of the tightening fitting 2 and the tightening fitting nut 4, the female tapered part 3d is tightened with respect to the male tapered part 2a. With this structure, the heat generating part 3 is moved to the nozzle 1 through the fitting 2 by compressing the fitting 2 to narrow the open state of the slot 2b and tightening it against the nozzle 1. Fixation or detachment is extremely flexible.

[Effect of idea]

As described above, according to an embodiment of the present invention, the configuration allows the heat generating part to be extremely easily fixed to or removed from the nozzle, and stable heat conduction can be obtained, making it easy to replace the heater due to breakage, etc. The cost is low, and the heat generating part can be replaced without modifying the expensive nozzle.

[Brief explanation of the drawing]

FIGS. 1 to 4 are side sectional views of an embodiment of the present invention. 1...Nozzle. 2...Mounting metal fittings. 2a...
Male taper part. 2b... Sliding part. 2c...Tightening screw part. 3... Heat generating part. 3a...exterior part.
...3b heating element. 3c... Good heat conductive member. 3d...
...Female taper part. 4...Tightening metal fittings, nuts.

Claims (1)

[Scope of utility model registration request] In a heater for a hot chip nozzle for a synthetic resin mold, the outer peripheral surface forms a male taper part, a slotted part for tightening is formed on the side wall, and a tightening screw part is formed at the end of the side wall. An electric heating element is buried inside a cylindrical fitting that is inserted and fixed into the hot chip nozzle, and a cylindrical good heat conductive member that has a female tapered inner surface that is inserted into the male tapered part. A nozzle characterized in that the heat generating part is sheathed with a heat resistant member whose outer peripheral surface is a heat resistant member having poorer heat conduction than the heat conductive member, and the nozzle forms a pair of assembled bodies, and is fixed to the nozzle with a tightening fitting and can be detached from the nozzle at will. heater structure.