JPH10100215A - Waste heat utilization device in injection molding machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively utilize waste heat emitted from a cylinder and to prevent quality of a molded article from being fluctuated and to improve appearance of the molded article and transferring properties. SOLUTION: A cylindrical cylinder cover 10 both ends of which in the axial direction reaches the back end part of the cylinder from the outer face 3a of a fixed stage 3 is arranged on the cylinder side so as to surround the cylinder 2 and a cylinder heat retaining zone 20 is formed by a space part between the inner wall face of the cylinder cover 10 and the outer wall face of the cylinder 2. A cylindrical mold cover 13 both ends of which in the axial direction reaches the facing wall faces of the fixed stage 3 and a movable stage 4 is arranged on the mold side so as to surround the mold and a mold heat retaining zone 21 is formed by a space part between the inner wall face of the mold cover 13 and the outer wall face of the mold 7. In addition, the cylinder heat retaining zone 20 and the mold heat retaining zone 21 are communicated with each other by an air flow path 16 through existence of a fan 16a and a vent path 18 provided with a vent fan 19 is communicated with the mold cover 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for utilizing waste heat in an injection molding machine, which can effectively utilize waste heat radiated from a cylinder heated by a heating means.

[0002]

2. Description of the Related Art Conventionally, an injection molding machine has been arranged in a state of being entirely exposed to an atmosphere in a molding factory, and waste heat radiated from a cylinder heated by a heating means can be effectively used. Instead, heat is radiated into the atmosphere in the molding factory.

[0003]

In the above prior art,
Since not only the cylinder but also the mold part is exposed to the atmosphere in the molding factory, it is directly affected by the temperature change of the atmosphere in the molding factory, and the temperature of the cylinder and the mold fluctuates during the molding process and molding is performed. Variations in product quality occur.
Further, the waste heat radiated from the cylinder is not effectively used, so that there is a problem that wasteful energy is consumed correspondingly.

The present invention has been made in view of the above-mentioned problems of the prior art, and can effectively utilize waste heat radiated from a cylinder and does not cause variation in the quality of a molded product. Further, it is an object of the present invention to realize a waste heat utilization device in an injection molding machine that maintains a mold surface temperature at a high temperature by using the waste heat and improves the surface appearance and transferability of a molded product. .

[0005]

In order to achieve the above object, an apparatus for utilizing waste heat in an injection molding machine according to the present invention comprises a fixed mold and a movable mold attached to a fixed plate and a movable plate, respectively. An injection molding machine provided with an injection device for injection-filling a molding material into a cavity of a mold comprising: a cylinder cover surrounding a cylinder of the injection device; a mold cover surrounding the mold; and the cylinder cover. And a cylinder heat insulating zone, which is a space surrounding the cylinder formed by the mold cover, and a mold heat insulating zone, which is a space surrounding the mold formed by the mold cover. The mold heat insulation zone is communicated with an air passage provided with a fan, and the mold heat insulation zone is communicated with the other end of an exhaust passage provided with an exhaust fan at one end. It is characterized in.

It is preferable that the cylinder cover is extendable and contractable in the axial direction of the cylinder, and the mold cover is extendable and contractable in the mold opening and closing direction.

[0007]

The air in the cylinder insulation zone, which is the space defined by the cylinder cover, becomes hot due to the waste heat radiated from the outer wall surface of the cylinder. As a result, the amount of heat radiation from the outer wall surface of the cylinder is reduced, and the fluctuation of the outside air temperature does not directly affect the cylinder, so that the temperature of the cylinder and the molding material in the cylinder is stabilized.

When the air temperature in the mold heat insulating zone, which is a space defined by the mold cover, is lower than a set temperature suitable for molding conditions, the fan provided in the air passage is started. By blowing the high-temperature air in the cylinder thermal zone into the mold thermal zone, the air temperature in the mold thermal zone can be raised to the set temperature. Conversely, when the air temperature in the mold heat retaining zone is higher than the set temperature, the fan is stopped and the exhaust fan is started to exhaust high-temperature air in the mold heat retaining zone through the exhaust passage. By doing so, low-temperature outside air can be introduced into the mold warming zone, and the air in the mold warming zone can be lowered to the set temperature.

[0009]

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is an explanatory view showing one embodiment of a waste heat utilizing apparatus in an injection molding machine according to the present invention.

An injection device E is provided on the right side of the drawing with a fixed platen 3 fixed on the bed 1 therebetween, and a movable platen 4 guided by a plurality of tie bars 5 is provided on the left side of the drawing. Has been established.

The injection device E includes a cylinder 2 which is heated by a heating means 2a such as a band heater mounted on the outer wall surface, an injection nozzle 2b mounted on the tip of the cylinder 2, and a rear end side of the cylinder 2. Hopper 6 provided in
A screw (not shown) is disposed in the cylinder 2 so as to be rotatable and movable in the axial direction. The molding material supplied from the hopper 6 is kneaded and melted, and the fixed nozzle 3 is fixed by the injection nozzle 2b. And a mold (not shown) of a mold 7 composed of a fixed mold and a movable mold attached to the movable platen 4, respectively.

In this embodiment, on the cylinder side, a cylindrical cylinder cover 10 whose both ends in the axial direction reach the rear end of the cylinder from the outer surface 3a of the fixed platen 3 is arranged so as to surround the cylinder 2. A space between the inner wall surface of the cylinder cover 10 and the outer wall surface of the cylinder 2 forms a cylinder heat insulating zone 20.

On the mold side, a fixed platen 3 is provided at both axial ends.
And a cylindrical mold cover 1 reaching the opposing wall surface of the movable platen 4
The mold 3 is disposed so as to surround the mold 7, and a mold insulation zone 21 is formed by a space between the inner wall surface of the mold cover 13 and the outer wall surface of the mold 7.

An upper portion of the wall surface of the cylinder cover 10 and a lower portion of the wall surface of the mold cover 13 are communicated with each other through an air passage 16 such as a duct. A fan 16a for blowing air toward 21 is interposed.

An exhaust path 18 for exhausting air in the mold heat insulating zone 21 is provided above the wall surface of the mold cover 13.
Is connected to one end, and an exhaust fan 19 is provided at the other end of the exhaust path 18.

In this embodiment, the cylinder cover 10
Is made of a heat-insulating structural material in which a bellows-like portion 11 is partially provided at an end of the fixed platen so as to be able to expand and contract in the axial direction of the cylinder 2 and a heat insulating material 12 is laminated on an inner wall surface thereof. Thereby, the heat insulating property of the cylinder heat insulating zone 20 is improved.

On the other hand, the mold cover 13 is provided with a bellows-like portion 14 at the center thereof so as to be expandable and contractible in the mold opening and closing direction and has a heat insulating material 15 laminated on the inner wall surface. By being made of a material, the heat insulation of the mold heat insulation zone 21 is improved. A temperature sensor 17 is provided at an appropriate position in the mold cover 13, and an opening (not shown) for dropping the molded product when the molded product is taken out is formed on a lower wall surface thereof. .

Next, the operation of this embodiment will be described.

The waste heat radiated from the outer wall surface of the cylinder 2 including the heating means 2a heats the air in the cylinder heat insulating zone 20 by the cylinder cover 10 to a high temperature. As a result, the outer wall surface of the cylinder 2 including the heating unit 2a is surrounded by the high-temperature air in the cylinder heat insulating zone 20, and the amount of heat radiation from the outer wall surface of the cylinder 2 including the heating unit 2a is reduced. At the same time, the fluctuation of the outside air temperature does not affect the outer wall surface of the cylinder 2 provided with the heating means 2a, and the temperatures of the cylinder 2 and the molding material in the cylinder are stabilized.

Also, the mold insulation zone 2 by the mold cover 13.
1 is detected by the temperature sensor 17, and when the air temperature in the mold heat insulating zone 21 detected by the temperature sensor 17 is lower than a set temperature suitable for molding conditions,
The fan 16a is activated to blow high-temperature air in the cylinder heat insulating zone 20 into the mold heat insulating zone 21 to increase the temperature to the set temperature.

Conversely, if the temperature detected by the temperature sensor 17 is higher than the set temperature, the fan 16
a, the exhaust fan 19 is started, and the high-temperature air in the mold heat insulating zone 21 is discharged from the exhaust path 18, and the low-temperature outside air is supplied from an opening (not shown) provided at the lower part of the wall of the mold cover 13. To lower the air temperature in the mold heat insulating zone 21 to the set temperature.

As a result, the mold insulation zone 2 surrounding the mold 7
The mold temperature can be maintained at a constant temperature by maintaining the air temperature in the mold 1 at the set temperature, and the mold temperature does not fluctuate even when the outside air temperature fluctuates. Disappears.

[0024]

Since the present invention is configured as described above, the following effects can be obtained.

Since the amount of heat radiated from the cylinder is reduced, energy can be saved, and even if the outside air temperature fluctuates, the surface temperature of the mold and the temperature of the cylinder and the molding material in the cylinder are stabilized. Variations in the quality of the product do not occur.

Further, even if the outside air temperature fluctuates, the temperature of the air in the mold heat insulating zone surrounding the mold formed by the mold cover can be maintained at a set temperature suitable for the molding conditions. The quality is improved.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a waste heat utilization device in an injection molding machine according to the present invention.

[Explanation of symbols]

 Reference Signs List 1 Bed 2 Cylinder 2a Heating means 2b Injection nozzle 3 Fixed plate 4 Movable plate 5 Tie bar 6 Hopper 7 Mold 10 Cylinder cover 11,14 Bellows 12,15 Insulation material 13 Mold cover 16 Ventilation path 16a Fan 17 Temperature sensor 18 Exhaust path 19 Exhaust fan 20 Cylinder insulation zone 21 Mold insulation zone

Claims (2)

[Claims] An injection device for injecting and filling a molding material into a cavity of a mold (7) comprising a fixed mold and a movable mold attached respectively to a fixed board (3) and a movable board (4). (E), a cylinder cover (10) surrounding the cylinder (2) of the injection device (E), a mold cover (13) surrounding the mold (7), A cylinder heat insulating zone (20), which is a space surrounding the cylinder (2) formed by the cylinder cover (10), and a space surrounding the mold (7) formed by the mold cover (13). And a cylinder heat insulating zone (21).
0) and the mold warm zone (21) are communicated by an air passage (16) interposed with a fan (16a), and the mold warm zone (21) has an exhaust fan (19) at one end. ) Is connected to the other end side of the exhaust path (18) provided with the waste heat. 2. The mold cover (13), wherein the cylinder cover (10) is extendable and contractable in the axial direction of the cylinder (2).
The waste heat utilization device in an injection molding machine according to claim 1, wherein the device is capable of expanding and contracting in a mold opening and closing direction.