JPH0335097B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a vacuum forming apparatus that can reduce the waiting time for cooling a molded product to be vacuum formed and increase productivity.

[Background technology]

Heating a synthetic resin sheet made of thermoplastic resin,
Vacuum forming apparatuses are often used to form a molded product having a shape that fits the mold by softening the material and vacuum adsorbing it to the mold.

In addition, in this vacuum forming, the molded product must be cooled down to a hardness suitable for removal after vacuum suction, and then removed from the molding die. On the other hand, in the conventional apparatus, the molded product was cooled each time after vacuum forming and was taken out after cooling, which resulted in a long waiting time for cooling and poor workability.

[Purpose of the invention]

An object of the present invention is to provide a vacuum forming apparatus that can reduce the waiting time for cooling and improve productivity by arranging molding molds back to back and performing vacuum forming and cooling alternately. It is said that

[Disclosure of the invention]

An embodiment of the present invention will be described below based on the drawings.

In the figure, a vacuum forming apparatus 1 includes a forming mold 2,
3 are placed back to back, and are provided with opening/closing valves 9 that alternately open and close the vacuum vent holes 6..., 7... of each molding die 2, 3 as the molds 3 are turned back to back. , and in this example,
The molding molds 2 and 3 are used to mold a decorative cover 10 that covers one side of the door, as shown in FIG. The decorative cover 10 has a flat plate shape, and has a base 12 that covers one side of a door frame 11 in which frame materials are arranged in a rectangular shape, and a peripheral wall 13 extending along the periphery of the door frame 11. Further, the base 12 is provided with a protrusion 15 that protrudes toward the rectangular hole of the door frame 11 through a plurality of steps 14 .

The mating mold 4 is attached to rotating rods 22 and 23 provided on the frame 21, and the frame 21 is also attached with a sheet pressing plate 25 and a heating plate 27.

The frame 21 has side plates 30 and 31 whose rear end portions are raised on both sides of the bottom plate 29, and the rotating rods 22 and 23 are oriented at the front edges of the upper ends of the side plates 30 and 31, respectively. It has a square shaft shape arranged together,
Further, mounting grooves 33, 33 are provided on the opposing surfaces.

The molding molds 2 and 3 have a rectangular plate-like substrate 36.
A raised part 15A with multiple steps for forming the protruding part 15 is provided with a groove part between it and the standing wall 13A for forming the peripheral wall 13 of the decorative cover 10, leaving the peripheral edge part 37, and Each corner has its back 2
The air vent holes 6..., 7... communicating with A, 3A are formed.

Further, the peripheral portion 37 has bolt holes 39 at its four corners and at an intermediate position into which bolts can be inserted by sinking their heads.
Further, recesses 40 are provided in parallel between the bolt holes 39.

Further, the molding molds 2 and 3 have the vacuum holes 6..., 7.
The bolt holes 3
are screwed back to back using bolts passing through 9,
The square hole 41 forms a gap 43 between the back surfaces of the molding molds 2 and 3, in which the vacuum vent holes 6, 7, and so on are opened.

Furthermore, the mounting plate 42 has guide pieces 4 provided on both sides thereof.
5, 45, mounting groove 3 of rotating rod 22, 23
3, 33 and can be bolted.

The rotating rod 22, as shown in FIG.
Hollow output shaft 47 of rotary seal 46 provided at 0
The center of the flange is bolted to the center of the flange, and a guide hole 4 that can be aligned with the output shaft 47 is provided at the center.
9 will be provided. Note that a seal fitting 51 is attached to the guide hole 49 and is urged forward by a spring 50. By inserting the mounting plate 42, the seal fitting 51 can be electrically connected to the gap 43 through a horizontal hole 52 provided at the center of the mounting plate 42.

Note that the electric rotary seal 46 is connected to a vacuum device 53.
Connect to via hose.

Further, the rotating rod 23 is pivotally supported by the output shaft of a deceleration motor M on the side plate 31, and the deceleration motor M is connected to a mating type 4
Then, the matching mold 4 is inverted by 180 degrees so that the molding molds 2 and 3 are positioned vertically and horizontally, respectively. Further, as shown in FIG. 3, the side plates 30 and 31 have locks that engage with the locking holes 55 on the sides of the rotating rods 22 and 23 in each horizontal state to hold the mating mold 4 in the horizontal state. Positioning tools 57, 57 each having a stopper piece 56 that can move forward and backward are provided.

In this example, the on-off valve 9 includes a valve body 59 that fits into the gap 43.

The valve body 59 is a relatively heavy plate with smooth front and back surfaces, and is positioned on the back surfaces 2A and 3A of the molding dies 2 and 3 located below, thereby making it possible to protect the molding dies 2 and 3 located below. 2, 3 vacuum vent holes 6..., 7
… is closed against vacuum pressure. Further, the valve body 59 falls every time the molding molds 2 and 3 are turned upside down, alternately closing the vacuum vent holes 6, 7, and opening the vacuum vent holes 6 located above.

The sheet holding plate 25 is connected to the side plates 30 and 31.
It is provided with a rectangular ring body 60 that is attached to a support shaft that spans over and has approximately the same shape as the peripheral edge portion 37. A cylinder 63 is pivotally supported on the support shaft via an arm 62 on its protrusion, and its expansion and contraction causes the lower surface of the ring body 60 to be aligned with the molding molds 2 and 3 in a horizontal state.
The synthetic resin sheet S placed on the peripheral edge 37 can be pressed and flipped upward. The ring body 60 is provided with a holding piece 64 using a bolt that can be fitted into the recess 40 of the peripheral portion 37.
...is being planted.

Further, the heating plate 27 is pivotally supported at the rear end portions of the side plates 30 and 31. As schematically shown in FIG. 6, the heating plate 27 has, for example, electric heaters 67 placed within a rectangular annular outer frame 66.
A reflecting plate 69 is attached above 7. Also heating plate 27
is connected to a reduction motor M1 attached to the side plate 30, thereby tilting between a horizontal state and a raised state.

[Effect]

As shown in FIG. 5, the synthetic resin sheet S is placed on the peripheral edge 37 of the mold 2 of the mating mold 4 which is stationary with the mold 2 in the upper position.
Further, the sheet presser plate 25 is tilted by the extension of the cylinder 63, and the synthetic resin sheet S is pressed by the presser piece 64 thereof. Further, the heating plate 27 is laid down horizontally, and the synthetic resin sheet S is heated using the heater 67.

When the synthetic resin sheet S is heated to a predetermined temperature and softened, the switching valve of the vacuum device 53 is opened. As shown in FIG. 6, the on-off valve 9 in the gap 43 falls downward and closes the vacuum vent hole 7 of the mold 3 below, so that the vacuum pressure is transferred to the rotary seal 46 and the output shaft. 47, guide hole 49, horizontal hole 5
The synthetic resin sheet S is molded along the molding die 2 by acting on the gap 43 from the vacuum hole 6 and suctioning air from the vacuum vent holes 6, and the decorative cover 10 having the flange-like ears is formed. It is formed.

After molding, the sheet pressing plate 25 and the heating plate 27 are
bounce up. Further, the mating mold 4 is turned over by the reduction motor M, and the molding mold 3 is held upward and horizontally. The synthetic resin sheet S is placed on the molding die 3, fastened and heated using the sheet presser plate 25 and the heating plate 27, and vacuum forming is performed. When the mating die 4 is reversed, the opening/closing valve 9 closes the vacuum vent hole 6 of the molding die 2 located below. Also, during the molding with the molding die 3, the decorative cover 10 is molded with the molding die 2 which is turned downward.
is cooled to a hardness suitable for removal. Therefore, the mating molds 4 can sequentially mold the decorative covers 10 without requiring any waiting time for cooling.

In the vacuum forming apparatus 1 of the present invention, the gap 43 is divided into two spaces facing the forming molds 2 and 3, and the vacuum forming apparatus 5 is connected to each space.
The device of the present invention can be modified in various ways, such as forming an on-off valve 9 that selectively opens and closes each vacuum vent hole 6 . . . , 7 .

〔Effect of the invention〕

In this way, the vacuum forming apparatus of the present invention has a pair of forming molds placed back to back and supports the combined mold in a reversible manner, and is provided with an on-off valve that alternately opens and closes the vacuum vent hole of each mold as the molds are reversed. Because
After vacuum forming using one mold, by inverting the mold, it can be cooled to a hardness suitable for taking out the molded product from the inverted mold during vacuum forming with the other mold, and therefore cooling is possible. It can have many effects such as eliminating waiting time, shortening the vacuum forming cycle, and increasing the productivity of the device.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing one embodiment of the present invention;
The figure is an enlarged cross-sectional view of the main parts, FIG. 3 is a cross-sectional view illustrating the positioning tool, FIG. FIG. 7 is a perspective view illustrating a molded product. 2, 3... Molding mold, 2A, 3A... Back, 4
... Matching mold, 6, 7 ... Vacuum vent hole, 9 ... Opening/closing valve, 22, 23 ... Rotating rod, 25 ... Sheet holding plate, 27 ... Warming plate, 43 ... Gap, 59 ... …
Valve body.

Claims (1)

[Scope of Claims] 1. A pair of molds for vacuum forming reversibly supports a pair of molds arranged back to back, and when the molds are inverted, each mold is evacuated. A vacuum forming device equipped with an on-off valve that alternately opens and closes holes. 2 The above-mentioned mating mold is inverted vertically, and
The on-off valve is a plate that is formed between the molding molds and is installed in the gap where the vacuum vent hole opens on the back side of each mold mold, so that it falls when the mating mold is reversed and alternately closes the vacuum vent hole. 2. The vacuum forming apparatus according to claim 1, wherein the valve body has a shape.