JPH07164507A - Mold block and cooling thereof - Google Patents

Abstract

PURPOSE:To uniformize the resin raw material extruded into the cavity space formed between the mold block and a mandrel by measuring the temps. of a plurality of mold blocks connected in a belt like state to cool the blocks to almost predetermined temp. by air cooling. CONSTITUTION:Many mold blocks 11 are connected in a belt like state to constitute a pipe making apparatus 1 equipped with two split mold groups 14, 15. The split mold group 14 is cooled by a first blower 5a while the split mold group 15 is cooled by a second blower 5b. At this time, in order to uniformly cool the mold blocks 11, the temps. of the mold blocks at the time of the making of a pipe are measured and the quantity or temp. of blown air is adjusted to control the temps. of the mold blocks. By this constitution, a resin raw material is uniformly extruded into the cavity spaces between the mold blocks 11 and a mandrel 12 and a product not lowered in appearance and physical properties and having a desired shape can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold block cooling method and a mold block used for producing a synthetic resin pipe such as a ribbed pipe.

[0002]

2. Description of the Related Art A plurality of mold blocks connected in a belt shape surrounds a mandrel, and a resin material is extruded into a cavity space formed between the mold block and the mandrel, and the mold blocks are sequentially sent out for circulation. It is known to form a tubular body by doing so (Japanese Patent Laid-Open No. 4-351522).

In order to cool the mold block, it is also known to apply air to a part of the resin contact surface of the mold block to cool the mold block.

[0004]

However, in the method of cooling the mold block by applying air to a part of the resin contact surface of the mold block, the temperature of the part other than the part exposed to the air does not decrease, and the mold block is not cooled. The surface temperature of the resin contact surface varies. Therefore, the amount of melted resin that flows into the rib molding portion of the cavity space of the mold block varies, and the rib molding portion of the cavity space of the mold block cannot be completely filled. Therefore, there is a problem that the appearance and physical properties of the product are deteriorated, a desired shape cannot be obtained, and a product defect occurs.

The present invention solves the above problems and an object thereof is to prevent deterioration of the appearance and physical properties of products.

[0006]

A method of cooling a mold block according to a first aspect of the present invention (hereinafter referred to as the present invention 1) includes a plurality of mold blocks connected in a belt shape so as to surround the mandrel to form a mold block. And a mandrel, and a step of extruding a resin raw material into a cavity space formed between the mandrel, a step of sequentially feeding and circulating a mold block to form a tubular body, and a step of adjusting the temperature of the mold block. A method for cooling a mold block used in the method, comprising measuring a temperature of the mold block and cooling the mold block to a substantially predetermined temperature by air cooling.

The mold block according to claim 2 (hereinafter referred to as the present invention 2) is a mold block used in the method for cooling a mold block according to the present invention 1, wherein fins are provided upright on the outer surface of the mold block. It is configured as follows.

A mold block according to claim 3 (hereinafter referred to as the present invention 3) is a mold block used in the method for cooling a mold block according to the present invention 1, wherein cooling holes are provided through the mold block. And

As a method of cooling the mold block, it is preferable to provide a plurality of blow ports or to expand the blow port in a tapered shape so that the air contacts the entire resin contact surface of the mold block. It is also preferable to measure the temperature of the mold block during pipe manufacturing, adjust the air flow rate and the air temperature, and adjust the mold block to a substantially predetermined temperature for cooling.

In the second aspect of the present invention, fins are provided upright on the outer surface of the mold block. As fins, it is preferable to provide a plurality of thin plate-like objects on the surfaces of the mold block excluding the resin contact surface and the connection surface. Further, it is preferable to measure the temperature of the mold block during pipe manufacturing and provide the fins at positions where the temperature of the mold block becomes uniform. Further, it is preferable to blow air to the fins to forcibly cool them. Further, it is preferable to provide holes in the fins to increase the surface area and improve efficiency. The width of the fin is 10 to 30 mm
Is preferred.

According to the third aspect of the present invention, cooling holes are provided through the mold block. As cooling holes, it is preferable to force air to flow through the holes for cooling. Further, it is preferable to measure the temperature of the mold block at the time of pipe making and to provide the cooling hole through the position such that the temperature of the mold block becomes a predetermined temperature. 1 to 3 cooling holes are provided, and the diameter is 10
-20 mm is preferable. Further, the passage of the cooling hole inside the mold block is preferably provided in a semicircular shape so as to pass through the same distance as the semicircular resin contact surface.

In the step of cooling to a substantially predetermined temperature, when it is cooled too much, it is preferable to raise the temperature with a heater, hot water or the like to adjust the slide base which is connected in contact with the mold block.

[0013]

In the method of cooling the mold block according to the first aspect of the present invention, the temperature of the mold block is measured and cooled to a substantially predetermined temperature by air cooling, so that the temperature of the mold block becomes substantially uniform and the temperature between the mold block and the mandrel is reduced. The resin raw material is uniformly extruded into the cavity space formed in.

In the mold block of the second aspect of the present invention, since the fins are provided on the outer surface, the heat dissipation area is increased, the fins are cooled, and the mold block is indirectly cooled.
Efficiently and uniformly cooled.

The mold block of the third aspect of the present invention is provided with the cooling holes, so that the heat radiation area is increased and the mold block is cooled from the inside thereof, so that the mold block is efficiently and uniformly cooled.

[0016]

Embodiments of the present invention will be described with reference to the drawings. 1 and 2 show a pipe manufacturing apparatus 1 of the present invention. FIG. 3 shows a manufacturing line using the pipe manufacturing apparatus 1.
FIG. 4 shows a mold block of the second invention. Figure 5
Shows a mold block of the third invention.

First, the pipe manufacturing method of the present invention will be described. The pipe manufacturing apparatus 1 for the ribbed pipe 2 includes a mandrel 12 by a plurality of mold blocks 11 connected in a belt shape.
The resin material 4 is extruded into the cavity space 3 formed between the mold block 11 and the mandrel 12, and the mold block 11 is sequentially sent out and circulated to form the ribbed tube 2. ing.

The mold block 11 includes a ribbed tube 2
A tube body molding portion 131 for molding a portion corresponding to the tube body 21 and a portion 132 corresponding to the rib 22 of the ribbed tube 2 are formed.

The mold block 11 thus constructed is
Two or more split mold groups 14 and 1 are connected in a belt shape.
The pipe manufacturing apparatus 1 having the number 5 is configured. That is, the split mold groups 14 and 15 are attached to the outer peripheral surfaces of the first slide base 16 and the second slide base 17 such that the mold surfaces 11 of the multiple mold blocks 11 face outward. And a part of the linear area 14
A first split mold group 14 formed by connecting in a ring having a and a second split mold group 15 having the same configuration as the first split mold group 14 are configured.

These first and second split mold groups 14, 15
Are arranged such that the respective mold blocks 11 and 11 face each other in a linear region of each other, and the second split mold group 15 is biased in the mold clamping direction with respect to the first split mold group 14. ing.

In the pipe manufacturing apparatus 1 thus configured, the first split mold group 14 and the second split mold group 15 are opposite to each other at a predetermined speed, that is, the first split mold group 14 in FIG. The second split mold group 15 circulates in the clockwise direction and in the counterclockwise direction, whereby each mold block 11, 11 of each group 14, 15 and the mandrel 12 have a cavity space 3 therebetween. The horizontal movement is performed in the same direction (rightward in the figure) in the state of forming.

Then, the molten resin material 4 extruded from the extruder 7 through the extrusion die 6 is fed into the cavity space 3 and cooled by the split die groups 14 and 15 to produce the ribbed pipe 2. .

Next, the cooling method of the present invention will be described. After manufacturing the ribbed pipe 2, the split mold groups 14, 15
Due to the high temperature of the molten resin material 4,
It is cooled by the blower 5. The first split mold group 14 that circulates and faces downward is cooled by the first blower 5a. The second split mold group 15 that circulates and faces downward is cooled by the second blower 5b. At this time, in order to uniformly cool the mold block 11, the temperature of the mold block at the time of pipe manufacturing is measured, and the air volume of the blown air and the temperature of the air are adjusted to adjust the temperature. In addition, the blower 5 is provided with three taper-shaped blower openings to blow the entire mold block 11. When it is cooled too much, hot water is poured into the slide base that is in contact with and connected to the mold block to raise the temperature for adjustment.

The size of the mold block 11 depends on the diameter of the ribbed tube 2, and the diameter of the ribbed tube 2 is 25.
In case of 0 mm, height 200 mm, length 350 mm, width 1
It is 50 mm. The material is aluminum.

Reference numeral 111 is a fin, and seven thin plate-like objects are provided on the surfaces of the mold block 11 excluding the resin contact surface and the connecting surface, that is, both lateral side surfaces. Also, the fin 11
1 is blown with air by the blower 5 to be forcibly cooled. The thickness of the fin 111 is 20 mm.

Reference numeral 112 is a cooling hole, and two holes communicating with the outside are provided inside the mold block. Air is blown into the cooling holes 112 by an air blowing nozzle to cool them. The air blowing nozzles are provided near both lateral sides of the mold block 11. Since both the blowing operation and the blowing operation are performed by one hole, the positions of the air blowing nozzles are alternately changed to the left and right. The diameter of the cooling hole 112 is 15 mm.

[0027]

According to the method of cooling a mold block of the present invention, since the temperature of the mold block is measured and the cooling is performed uniformly by air cooling, the temperature of the mold block becomes approximately a predetermined temperature, and the temperature between the mold block and the mandrel is reduced. The resin raw material is uniformly extruded into the cavity space formed in. Therefore, the appearance and physical properties of the product are not deteriorated, a desired shape is obtained, and product defects do not occur.

[Brief description of drawings]

FIG. 1 is a side view of a partially broken view showing an outline of a main part of a pipe manufacturing apparatus of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a schematic view showing a production line using a pipe producing apparatus.

FIG. 4 is a perspective view showing a mold block of the second invention.

FIG. 5 is a perspective view showing a mold block of the third invention.

[Explanation of symbols]

 1 Pipe Making Device 11 Mold Block 12 Mandrel 2 Pipe with Rib 3 Cavity 4 Resin Material 5 Blower 111 Fin 112 Cooling Hole

Claims (3)

[Claims] 1. A step of surrounding a mandrel with a plurality of mold blocks connected in a belt shape and extruding a resin raw material into a cavity space formed between the mold block and the mandrel, and sequentially sending the mold blocks. A method of cooling a mold block used in a pipe manufacturing method, comprising: a step of circulating the tube to form a tube; and a step of adjusting the temperature of the mold block, wherein the temperature of the mold block is measured and air-cooled. A method of cooling a mold block, characterized in that the mold block is cooled to a substantially predetermined temperature. 2. A mold block used in the method for cooling a mold block according to claim 1, wherein fins are provided upright on an outer surface of the mold block. 3. A mold block used in the method for cooling a mold block according to claim 1, wherein a cooling hole is provided through the mold block.