JP3504492B2 - Manufacturing equipment for cast polyamide resin moldings - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for producing a cast polyamide resin molded article, and more particularly to an apparatus for producing a cast polyamide resin molded article that eliminates voids inside the plate-shaped article and sink marks on the surface. is there.

[0002]

2. Description of the Related Art As shown in FIG. 7, a mold 50 used in an apparatus for producing a cast polyamide resin molding has a corner portion 53 between a pair of side plates 51, 51 made of aluminum, iron or the like.
A spacer 52 having a right angle is interposed, and a packing 54 for preventing liquid leakage is attached to the spacer 52 to form a cavity 55. Then, the mold 50 is heated in a hot air oven to a temperature set to 180 to 190 ° C,
After taking out the mold having a predetermined temperature from the furnace, the polymerizable lactam liquid was poured into the mold, and the mold was put in the hot air oven again to carry out polymerization.

The distance from the product surface 57 of the spacer 52 to the packing 54 needs to be several millimeters in terms of the structure, and a gap of several mm is provided between the side board surface 58 and the spacer surface 59. Burrs occurred on the part.

[0004]

However, the polymerizable lactam solution shrinks at the polymerization and crystallization stages, but this burr interferes with the polymerization and prevents the polymer from freely shrinking, resulting in voids near the spacer of the polymer. Surface sink marks were often generated in the thickness direction. The present invention solves such problems, and an object of the present invention is to provide an apparatus for producing a cast polyamide resin molded body that eliminates voids inside the plate-shaped molded body and sink marks on the surface.

[0005]

That is, in the invention according to claim 1 of the present application, a cavity is formed between a pair of side panels with a spacer interposed, and a polymerizable lactam liquid is cast into the cavity. In an apparatus for producing a plate-shaped body of cast polyamide resin by anionic polymerization by means of anion polymerization, packing for preventing leakage of the polymerizable lactam liquid is interposed between the side plate and the spacer, and part of the cavity surface is It is used in the manufacturing equipment for cast polyamide resin moldings in which the corners of the spacer to be formed are tapered to the side panel, and the corner of the spacer that forms part of the cavity surface is tapered to the side panel at a specified angle. By making it a surface, there is no obstruction to the shrinkage of the molded body due to the entrapment of burrs, the molded body can shrink freely, and voids near the spacer and surface sink in the thickness direction Camphor can be.

According to the second aspect of the present invention, there is provided a casting polyamide resin molded body manufacturing apparatus in which at least one of the side panels is movable and the spacers can be clamped and fixed to be opened.

According to the invention of claim 3 of the present application, at least one of the pair of side panels, at least one of which is movable and whose temperature is adjustable, is capable of adjusting the temperature.
Place more than one middle board, insert a spacer between each pair of side boards and middle boards, move one side board to the other side board, and clamp and fix each board and spacer integrally Then, there is provided an apparatus for producing a cast polyamide resin molded body having a cavity for casting a polymerizable lactam liquid. With this device, the molded body can shrink freely, eliminating voids near the spacer and surface sink marks in the thickness direction.
Since the heat medium oil is caused to flow inside the member forming the cavity to control the temperature, it is possible to manufacture a molded body having a large thickness and no cavity defect. The temperature control and temperature control of the mold from the time of casting the polymerizable lactam liquid to the demolding of the molded body can be accurately controlled, and heat loss is small.

In the invention according to claim 4 of the present application, the angle of the tapered surface formed on the inner peripheral surface of the spacer is 10 to 50 degrees, which is an angle at which the molded body can freely shrink.

According to a fifth aspect of the present invention, in the method for producing a cast polyamide resin molded body, the spacer is a frame body having one side open, and the frame body has a passage through which the heat transfer oil flows. is there.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a front view of an apparatus for producing a cast polyamide resin molded product according to the present invention, FIG. 2 is a plan view showing a state at the time of molding in FIG. 1, and FIG. 3 is a manufacturing process shown in FIG. FIG. 4 is a front view of the spacer used for the apparatus with a part notched, FIG. 4 is a front view of the spacer, FIG. 5 is a sectional view taken along line AA of FIG. 2, and FIG.

A casting polyamide resin molded body manufacturing apparatus 1 according to the present invention includes a stationary member 2 having a side panel 4 mounted thereon, a movable member 3 having a side panel 4 similarly mounted thereon, the stationary member 2 and the movable member. It is composed of a heat medium oil circulation device 6 and a spacer 5 which is interposed between the spacers 3 to form a cavity 7.

In the fixing member 2, a heat insulating plate 11 is vertically fixed to a supporting plate 10 arranged horizontally on the leg portion 9, and a heat insulating material 12 such as rock wool is attached to the entire back surface of the heat insulating plate 11. Further, the side plate 4 is held on a front surface of the heat insulating plate 11 by a frame 13 protruding therefrom and mechanically fixed.

As shown in FIG. 3, the side board 4 is a hollow body formed of a plate made of metal such as aluminum or iron. Inside the sealed interior, bars 15 extending in the width direction are provided at regular intervals. The
It has a communicating oil passage 16 for flowing the heat transfer oil. When the heat transfer oil enters from the oil port 17 provided on the lower side of the side panel 4, it flows through the communicating oil passage 16 to heat the inside of the side panel 4 evenly and discharges it from the oil outlet 18 provided on the upper side. , To the heat medium oil circulation device 6 via the pipe 19 and circulates between them.

In the moving member 3, a heat insulating plate 11 is vertically fixed to a horizontally arranged support plate 10 like the fixed member 2, and a heat insulating material 12 is attached to the entire back surface of the heat insulating plate 11 . At the same time, the side panel 4 is held on a front surface of the heat insulating plate 11 by a frame 13 and is mechanically fixed. However, the moving member 3 is provided with the carriage 20 on the support plate 10, and can be manually or automatically moved to the fixed mold body 2 side on the rail 22 provided on the substrate 21 and can be separated from it. The side panel 4 has the same structure as that mounted on the fixing member 2.

As shown in FIG. 4, the spacer 5 is a U-shaped frame body having one side open, and through holes 25 through which bolts are inserted are provided at regular intervals on each side. There is an oil passage (not shown) for passing the heat transfer oil inside the frame, and the heat transfer oil passes through the oil passage 27 provided on the lower side and exits the oil outlet 28 provided on the upper side. Then, the spacer 5 is heated. The spacer 5
Is a frame 13 provided on the fixed member 2 or the movable member 3.
It is installed in and mechanically fixed. However, spacer 5
In order to enhance the sealing effect between the side panel 4 and the side panel 4, a packing 30 made of a rubber elastic body such as urethane or silicon rubber may be attached to both surfaces of the frame body of the spacer 5. In this case, it is not necessary to mechanically fix the spacer 5 to the fixed mold body 2 or the moving member 3.

The heat transfer oil circulating device 6 is provided with a heating device for heating the heat transfer oil contained in the tank and a pump for circulating the heat transfer oil, and is connected to the fixed member 2 and the moving member 3 via the pipe 19. It is connected to the mounted side panel 4 and spacer 5.

Further, in the apparatus of the present invention, a pair of side panels 4, 4 may be fixed, and a spacer 5 may be interposed therebetween to form a cavity 7. Of course, each side panel 4,
It is possible to control the temperature of the heat exchanger 4 and the spacer 5 by the heat medium oil circulation device 6. Furthermore, a pair of side panels 4 with adjustable temperature,
4, at least one or more middle plates (not shown) capable of temperature control are arranged, and a spacer is interposed between each pair of side plates 4 and the middle plates. May be moved to the other side panel 4 to sandwich and fix each panel and the spacer 5 integrally to form a plurality of cavities 7.

Therefore, in the present invention, as shown in FIGS. 5 and 6, the packing 30 for preventing the leakage of the polymerizable lactam liquid is interposed between the pair of side plates 4, 4 and the spacer 5, and the cavity surface is formed. The corner portion 32 of the spacer 5 forming a part of 31 is formed with a taper surface 34 having an angle θ of 10 to 50 degrees with respect to the side board surface 33. For this reason,
There is no obstruction to the shrinkage of the molded body due to burr entrapment,
The molded body can freely shrink, and voids near the spacer 5 and surface sink marks in the thickness direction can be eliminated.

When the angle θ of the tapered surface 34 is less than 10 degrees, the shrinkage of the molded body is hindered and voids near the spacers 5 and surface sinks in the thickness direction are apt to occur. On the other hand, 50 degrees. When it exceeds, the wall strength of the packing groove 35 is lowered and this portion is easily deformed during use. Further, a release agent such as silicone oil may be applied to the tapered surface 34 in order to shrink the molded body freely.

Next, a method for producing a cast polyamide resin molded article using the production apparatus according to the present invention will be described below. First, after the spacer 5 having a predetermined thickness in which the angle θ of the corner portion 32 is set to 25 degrees is installed so as to be in contact with the side panel 4 mounted on the fixed member 2, the moving member 3 is moved to separate the spacer 5 into two pieces. A cavity 7 for sandwiching the side plates 4 and 4 and for casting a polymerizable lactam liquid is formed. At this time, the spacer 5 and the two side panels 4 and 4 are mechanically fixed by a bolt or a clamp device in place of this, and the heat medium oil is introduced from the heat medium oil circulation device 6 to 130 to 160 ° C.
Adjust temperature and preheat.

Then, the polymerizable lactam liquid is added to the cavity 7.
It is cast into and polymerized anionically in a closed state. The polymerization time is 20 to 100 minutes, and when this is completed, the spacer 5
After mechanically opening the two side boards 4 and 4, the moving member 3 is moved to the original position. The cast polyamide resin molding obtained can be easily taken out of the mold. The molded body can be freely shrunk, and voids near the spacer and surface sink marks in the thickness direction can be eliminated.

The polymerizable lactam liquid is an ω-lactam to which an anionic polymerization catalyst and an anionic polymerization initiator are added. The ω-lactam is substantially anhydrous α-piperidone, ε-caprolactam, ω-lauro. A lactam or a mixture of two or more thereof, and industrially advantageous lactams are ε-caprolactam and ω-laurolactam.

As the anionic polymerization catalyst, known ω-lactam polymerization catalysts such as sodium hydride, lithium hydride, sodium and potassium can be used, and the addition amount thereof is 0. It is 1 to 2.0 mol%. And as the anionic polymerization initiator, for example, N-acetyl-ε-caprolactam, isocyanate,
It is a diisocyanate, a urea derivative, a urethane, or an isocyanurate derivative, and the addition amount thereof is preferably in the range of 0.05 to 1.0 mol% with respect to the ω-lactam.

In the above manufacturing method, the anionic polymerization catalyst is ω
-A method of adding an initiator for anionic polymerization to a lactam and dissolving it, and then adding and mixing it at the time of casting, or ω-containing an anionic polymerization catalyst and ω-containing an anionic polymerization initiator-
It is adjusted by the method of adding and mixing lactam and lactam at the time of casting.

In carrying out the method of the present invention, in addition to the above-mentioned components, oils which do not inhibit polymerization, waxes, lubricants such as zinc stearate and calcium stearate, and reinforcing materials such as carbon fibers and glass fibers are added. Is also possible.

[0026]

As described above, in the invention described in each claim of the present application, the packing for preventing the leakage of the polymerizable lactam liquid is interposed between the side panel and the spacer, and a part of the cavity surface is formed. In a manufacturing apparatus for cast polyamide resin moldings in which the corners of the spacer are tapered to the side panel, the corner of the spacer forming a part of the cavity surface is a tapered surface at a predetermined angle to the side panel. By doing so, there is no hindrance to the contraction of the molded body due to the entrapment of burrs, the molded body can freely shrink, and there is an effect of eliminating voids near the spacer and surface sink marks in the thickness direction.

[Brief description of drawings]

FIG. 1 is a front view of an apparatus for producing a cast polyamide resin molded body according to the present invention.

FIG. 2 is a front view showing a state at the time of molding in FIG.

3 is a partially cutaway front view of a side panel used in the manufacturing apparatus shown in FIG.

FIG. 4 is a front view of a spacer.

5 is a cross-sectional view taken along the line AA of FIG.

FIG. 6 is an enlarged view of part B in FIG.

FIG. 7 is a cross-sectional view of a mold used in a conventional casting polyamide resin molded body manufacturing apparatus.

[Explanation of symbols]

2 fixing members 3 moving members 4 side panel 5 spacers 7 cavities 30 packing 32 corner 33 Side panel 34 Tapered surface 35 packing groove

Claims (5)

(57) [Claims] 1. A plate-shaped body of a cast polyamide resin is formed by forming a cavity between a pair of side panels with a spacer interposed, and casting a polymerizable lactam liquid in the cavity to perform anionic polymerization. In the manufacturing apparatus, a packing for preventing leakage of the polymerizable lactam liquid is interposed between the side panel and the spacer, and a corner portion of the spacer forming a part of the cavity surface is tapered with respect to the side panel surface. An apparatus for producing a cast polyamide resin molded article, which is characterized in that 2. The apparatus for producing a cast polyamide resin molded article according to claim 1, wherein at least one of the side panels is movable. 3. At least one middle plate capable of temperature adjustment is disposed between a pair of side plates capable of moving at least one of them and capable of temperature adjustment. A spacer is interposed between each board, and one side board is moved to the other side board to form a cavity for casting the polymerizable lactam liquid by sandwiching and fixing each board and the spacer integrally. Item 1. An apparatus for producing a cast polyamide resin molded article according to item 1. 4. The angle of the tapered surface formed at the corner portion of the spacer is 10 to 50 degrees.
An apparatus for producing the cast polyamide resin molding described. 5. The spacer is a frame body whose one side is open,
4. A frame having a passage for allowing a heat transfer oil to flow therein.
Or the apparatus for producing a cast polyamide resin molded article according to 4.