JPH06190846A - Slush molding die and heater therefor - Google Patents

Abstract

PURPOSE:To freely control a mold temperature at an arbitrary position without complicating facilities by a method wherein a means for partially changing a degree of mold temperature increase is provided on a rear surface of a mold. CONSTITUTION:On the rear surface of a slush mold B, areas of different infrared ray absorption amount are partially provided. A hot air generating machine 11 is provided for heating the slush mold B by hot air. Infrared heaters 21 are provided for heating the slush mold B by emitting infrared rays to the rear surface of the mold.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a slush molding die and a heating device therefor, and more particularly to a measure for controlling a mold temperature.

[0002]

2. Description of the Related Art Generally, uniform heating of the entire slush molding die is necessary for molding a sheet-like material such as a skin material having a uniform thickness. Therefore, as disclosed in, for example, Japanese Patent Application Laid-Open No. 4-176613, heating is performed while rotating a slush molding die in a heating furnace.

[0003]

However, in the slush molding die, there are portions where the heat is difficult to reach and where the die thickness is large due to the die structure, and these portions are generally difficult to heat up. Even if the slush molding die is rotated as described above, it is difficult to uniformly heat the entire die. Further, in the case of the above-mentioned publication example, a rotating device is required and the equipment becomes complicated.

On the other hand, depending on the purpose, not only the case where the entire mold is heated uniformly, but there is a case where it is desired to partially raise the temperature to a higher temperature than other places. For example, this is the case where it is desired to partially thicken the sheet-shaped material.

However, also in this case, it is difficult to heat a desired portion to a desired temperature for the same reason as above. Further, the mold temperature cannot be partially controlled by the method of the above-mentioned publication example.

The present invention has been made in view of the above points, and an object of the present invention is to complicate the equipment by providing a means on the back surface of the mold for partially varying the degree of increase in the mold temperature. It is to try and control the mold temperature at any place without any control.

[0007]

In order to achieve the above-mentioned object, a first solution means of the present invention is characterized in that a region having a different infrared absorption amount is partially provided on the back surface of the mold.

A second solution of the present invention is to heat the slush molding die to a predetermined temperature in the process of conveying the slush molding die in which a region having a different infrared absorption amount is partially provided on the back surface of the die. In the heating device, hot air heating means for heating the slush molding die from the molding surface side with hot air is provided. Furthermore, an infrared heating means for irradiating the back surface of the mold with infrared rays to heat the slush molding die is provided.

[0009]

With the above construction, in the first and second solving means of the present invention, the slush molding die is heated by the hot air of the hot air heating means in the conveying process, and then is heated by the infrared rays emitted from the infrared heating means. The degree to which the mold temperature rises differs between the area that is heated and partially provided on the back surface of the mold and has a different amount of infrared absorption, and the other area.

Therefore, if the infrared ray absorption amount is increased in a portion where the heat is hard to reach due to a shadow or a portion where the die thickness is large, these portions tend to be heated and the difference in die temperature with other portions is reduced, and the entire die is reduced. Is heated quickly and uniformly.

On the other hand, for example, when it is desired to partially thicken the sheet-like material, the mold temperature needs to be partly higher than the other parts. In this case, the mold temperature is partly increased. By providing a region capable of absorbing a large amount of infrared rays in a place where the temperature is desired to be higher than that in other places, the desired place can be easily heated to the desired temperature.

Further, since it is only necessary to partially provide an area for varying the absorption amount of infrared rays on the back surface of the slush molding die and to additionally provide infrared heating means, the rotating device as in the publication is unnecessary. The equipment becomes simple.

[0013]

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

FIGS. 1 and 2 show a form A which is framed in a box shape.
3 shows a slush molding die B according to an embodiment of the present invention set to FIG. The slush molding die B has a molding surface b1 corresponding to the shape of the sheet-like material to be molded, and the mold back surface b2 of the slush molding die B opposite to the molding surface b1.
Are formed in an uneven shape corresponding to the shape of the molding surface b1.

As a feature of the present invention, the first coat layers c1 and c as regions for making the infrared ray absorption amount different near the outer periphery of the mold back surface b2 of the slush molding mold B and in the middle thereof.
1 (areas shown with meshes in FIG. 1) are partially formed, and each of the first coat layers c1 is formed by applying heat-resistant black paint or the like on the mold back surface b2. This is an area that is easily absorbed. In addition, a second surface is formed on the mold back surface b2 of the slush molding mold B except for the first coat layers c1.
The coat layers c2 and c2 are formed, and the respective second coat layers c2 are formed.
Is formed, for example, by applying a heat resistant white paint or the like to the back surface b2 of the mold, and is an area in which infrared rays are difficult to be absorbed. That is, since the area of each of the first coat layers c1 is shaded by hot air heating and heat is hard to reach, the infrared absorption degree of the area is set to the second degree.
It is higher than the area of the coat layer c2.

The slush molding die B thus constructed is set on the mold A with the molding surface b1 facing downward, and is heated to a predetermined temperature by the heating device D shown in FIG.

In FIG. 3, reference numeral 1 is a heating furnace, 3 is a transfer device installed in the heating furnace 1, and the transfer device 3 is
A total of eight sprocket wheels 5, 5, ... with four on each side (four in front are visible in Fig. 3), and two chains 7, 7 (one in front is visible in Fig. 3) , A plurality of hangers 9, 9, ... Are attached to the chains 7, 7 at predetermined intervals, and the engaging protrusions a1, a1 of the mold A are attached to the hangers 9, respectively. The slush molding dies B are suspended and supported by being engaged with each other, and a plurality of slush molding dies B are
.. are conveyed in the heating furnace 1 to heat them to a predetermined temperature.

A hot air generator 11 as a hot air heating means is installed outside the upper wall of the heating furnace 1. The hot air generator 11 is connected to the blower 13 and the duct 15 and is provided in the heating furnace 1. .. are blown into the heating furnace 1 to heat the slush molding die B from the molding surface b1 side by the hot air. Then, the heated hot air is returned to the hot air generator 11 through the suction port 19 provided on the upper side of the heating furnace 1 and is circulated and used.

Infrared heaters 21, 21, ... As infrared heating means are installed inside the upper wall of the heating furnace 1 on the downstream side (the left end side in FIG. 3) of the hot air generator 11 in the die conveying direction.
Each infrared heater 21 is provided on the mold back surface b2 of each slush molding mold B heated by the hot air of the hot air generator 11.
Infrared rays are radiated to heat each slush molding die B so that the infrared absorption of the first coat layers c1 and c1 is higher than that of the second coat layers c2 and c2.

In FIG. 3, reference numeral 23 is a mold take-out space for carrying the heated slush molding die B into the resin raw material supplying step which is the next step, and 25 is a demolding step for demolding the molded product. It is a die mounting space for delivering the subsequent slush molding die B to the transfer device 3 in order to carry it into the die heating step.

As described above, in this embodiment, the first coat layers c1 and c1 having a high degree of infrared absorption are formed on the mold back surface b2 in the area shaded by the hot air heating of the slush molding die B, and the hot air generator 11 is used. Infrared heater 2 after heating with hot air
Since infrared radiation heating is performed by 1, 2, ..., The mold temperature of each first coating layer c1 that is shaded by hot air heating is the second
Although it is lower than the mold temperature of the coat layer c2, this mold temperature difference can be eliminated by increasing the mold temperature of each of the first coat layers c1 by infrared irradiation heating, and the entire mold can be heated quickly and uniformly. can do.

In the above embodiment, the first coat layers c1 and the second coat layers c2 are formed on the mold back surface b2 of the slush molding die B, and the infrared heaters 21 and 2 are used.
Since it is only necessary to attach 1, ..., It is not necessary to install the rotating device as in the publication example, and the equipment can be simplified accordingly.

In the above embodiment, the case where the mold temperature of the slush molding die B is made uniform throughout is shown.
For example, when it is desired to partially thicken the sheet-like material, it is necessary to partially set the mold temperature to be higher than that of other portions. In this case, a region (first coat layer c1) capable of absorbing a large amount of infrared rays may be provided at a position where the mold temperature is to be made partially higher than that at other positions, whereby the desired position can be easily obtained. Can be heated to the desired temperature. Further, although the infrared heating means is provided on the downstream side of the hot air heating means in the die conveying direction, it may be provided at the same position so that both heating means act on the die at the same time.

[0024]

As described above, according to the present invention as set forth in claims 1 and 2, the slush molding die is provided with a partial region on the back surface of the slush molding die for varying the amount of absorption of infrared rays. Since the mold was heated by the hot air heating means and the infrared heating means, it is possible to increase the infrared absorption amount in the place where heat is difficult to reach due to the hot air heating or the place where the mold thickness is large. The mold temperature difference can be reduced and the entire mold can be heated quickly and uniformly. Further, for example, even when it is desired to partially thicken the sheet-shaped material, the mold temperature can be partially raised to a higher temperature than other portions. Furthermore, since it is only necessary to partially provide an area for varying the amount of absorption of infrared rays on the back surface of the slush molding die and to additionally provide infrared heating means, simplifying the equipment without the rotating device as in the publication example. Can be planned.

[Brief description of drawings]

FIG. 1 is a perspective view of a slush molding die set in a mold.

FIG. 2 is a vertical cross-sectional view of a slush molding die set in a mold.

FIG. 3 is a vertical cross-sectional view of a heating device.

[Explanation of symbols]

11 hot air generator (hot air heating means) 21 infrared heater (infrared heating means) B slush molding die b2 mold back surface c1 first coat layer (area for varying infrared absorption amount) D heating device

Claims (2)

[Claims] 1. A slush molding die, wherein a region for varying the amount of absorption of infrared rays is partially provided on the back surface of the die. 2. A heating device for heating a slush molding die to a predetermined temperature in the process of transporting the slush molding die in which a region having a different amount of absorption of infrared rays is provided on the back surface of the die, the heating device comprising: A slush molding die comprising a hot air heating means for heating the slush molding die from the molding surface side with hot air, and an infrared heating means for irradiating the slush molding die with infrared rays on the back surface of the die for heating. Heating device.