JPS5830669Y2 - Heater with water cooling - Google Patents

Description

[Detailed description of the invention] The heater attached to the extrusion cylinder of a synthetic resin extrusion molding machine has a structure that can be cooled by air cooling or water cooling in order to prevent the extrusion cylinder from overheating.

Some of the water-cooled heaters mentioned above have a structure in which heating wires and water-cooled pipes are cast into the thickness of the heat exchanger plate when the heat exchanger plate is shaped to contact the outer peripheral surface of the extruded cylinder. In this water-cooled heater, the heat exchanger plate expands due to the heat emitted from the heating wire, while the water-cooled pipe is cooled by the cooling water and contracts in the opposite way to the heat exchanger plate.
The disadvantage is that the pipe wall is strained, causing cracks and breakage.

Therefore, if a pipe with a thick pipe wall is used as a water-cooled pipe, the above drawback may be solved, but in that case, the pipe has to be bent in order to be cast into the heat exchanger plate in a meandering manner. It has the disadvantage that it is difficult to apply and is not practical.

The present invention aims to provide a water-cooled heater that can eliminate the various drawbacks of the conventional heater by constructing the water-cooled pipe with a double-walled pipe.

The embodiments of the present invention will be described below based on the drawings.
is a heat transfer plate, which is formed into a semicircular shape using a material that easily conducts heat such as aluminum, brass, filler metal, or iron, and has a pair of integrally formed flanges 2°2 at each end. The plate pieces 3, 3 are butted together in a cylindrical shape, and the entire inner wall thereof is molded so as to be in contact with the outer peripheral surface of an extrusion cylinder in a synthetic resin extrusion molding machine.

Reference numerals 4 and 4 indicate through holes drilled in the flanges 2 and 2 of each plate piece 3, 3, and by inserting a screw bottle into these holes and screwing a nut into the hole, the plate pieces 3, 3 can be integrated. join to.

Reference numerals 5 and 5 denote heating wires such as sheathed wires that are cast in a meandering manner within the thickness of each plate piece 3, 3, and connect the power supply connection end from the end face of one flange 2 of each plate piece 3, 3. 6,6 stands out.

Reference numerals 7 and 7 designate water cooling pipes that are cast in a meandering manner within the thickness of each plate piece 3, 3, and are connected to the water inlet 8 from the upper side of one of the flange edges 2 of each plate piece 3, 3. Exit 9 is protruding.

This water cooling pipe 7.7 is connected to the outer pipe 10 as shown in the third figure.
It consists of a double-walled pipe with an inner pipe 11 inserted into it.

Next, to explain how to use the water-cooled heater constructed as described above, the outer peripheral surface of the extrusion cylinder is
, 3, butt the plate pieces 3 and 3 together in a cylindrical shape,
The installation of the heater is completed by tightening the flanges 2, 2 with threaded bolts and nuts.

Then, the heating wires 5, 5 are energized, and the generated electric heat is transferred from the heat exchanger plate 1 to the extrusion cylinder, where it is heated and extruded.

When the extrusion cylinder is overheated beyond a predetermined temperature, the temperature detection device is activated to cool it by passing water through the water cooling pipe 7.7, and when the extrusion cylinder has been cooled to the predetermined temperature, the temperature detection device is activated. Stop water flow.

Note that the heat transfer plate 1 may be formed by tightening a pair of plate pieces each having a semicircular bottom shape into a cylindrical shape using a tightening band.

Further, the shape of the heat exchanger plate is not limited to the shape shown in the above embodiments, but can be changed as appropriate depending on the object to be heated.

As mentioned above, the present invention takes advantage of the double-walled water-cooled pipe by casting it into the heat exchanger plate, so the pipe wall is reinforced.
Since it can withstand the effects of temperature differences between heating and cooling, it can prevent water cooling pipes from cracking or breaking.

In addition, the pipe walls of the outer pipe and the inner pipe can be made thinner, and when bent, both the inner and outer pipes are appropriately shifted, so it has advantages such as being much easier to bend than a single pipe.

[Brief explanation of the drawing]

Figure 1 is a front view of the heater with water cooling according to the present invention, Figure 2
The figure is a partially sectional plan view of FIG. 1, and FIG. 3 is a partially enlarged sectional view of FIG. 1...Heat exchange plate, 2...Brim edge, 3...
... Plate piece, 5 ... Heating wire, 7 ...
Water cooling pipe, 8... Inlet, 9... Outlet, 10... Outer pipe, 11... Inner pipe.

Claims (1)

[Scope of utility model registration request] In a heater with water cooling, in which a heating wire such as a sheathed wire and a water cooling pipe for passing cooling water are cast into a heat transfer plate attached to an extrusion cylinder or other heated object in a synthetic resin extrusion molding machine, the water cooling pipe is connected to the outer pipe. A heater with water cooling characterized by being composed of a double-walled pipe with an inner pipe inserted.