JPH11235725A - Apparatus for producing cast type polyamide resin molded object - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the producing apparatus with which voids in a plate-shaped molded object or the like on the surface thereof are eliminated. SOLUTION: A spacer 5 is interposed between a pair of side panels 4, 4 to from a cavity 7 and a polymerizable lactam soln. is injected into the cavity 7 to be anionically polymerized to produce a plate-shaped product of a cast polyamide resin. In this apparatus, packings 30 preventing the leak of the polymerizable lactam soln. are interposed between the side plates 4 and the spacer 5 and the corner parts 32 of the spacer 5 forming a part of a cavity surface 31 are formed into taper surfaces 34 with respect to side plate surfaces 33.

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 in which voids and sink marks on a plate-shaped molded article are eliminated. is there.

[0002]

2. Description of the Related Art As shown in FIG. 7, a mold 50 used in an apparatus for manufacturing a cast polyamide resin molded body has a corner 53 between a pair of side plates 51, 51 made of aluminum, iron or the like.
A cavity 55 is formed by interposing a right angled spacer 52 and attaching a packing 54 for preventing liquid leakage to the spacer 52. Then, the mold 50 is heated in a hot blast stove to a temperature set at 180 to 190 ° C.,
After the mold at the predetermined temperature was taken out of the furnace, a polymerizable lactam solution was poured into the mold, and the mold was placed in a hot-blast furnace again for polymerization.

Since the distance from the product surface 57 of the spacer 52 to the packing 54 must be several millimeters in structure, and the side panel surface 58 and the spacer surface 59 have a gap of several millimeters. Burrs occurred on the part.

[0004]

However, the polymerizable lactam solution shrinks during the polymerization and crystallization stages, but the burrs hinder the polymer from shrinking freely. Surface sinks in the thickness direction often occurred. The present invention has been made to solve such a problem, and an object of the present invention is to provide an apparatus for producing a cast polyamide resin molded article in which voids and sink marks on the surface of the plate-shaped molded article are eliminated.

[0005]

That is, according to the first aspect of the present invention, a cavity is formed between a pair of side panels with a spacer interposed therebetween, and a polymerizable lactam liquid is poured into the cavity. In an apparatus for producing a plate-shaped body of cast polyamide resin by anionic polymerization, a packing for preventing leakage of the polymerizable lactam liquid is interposed between the side plate and the spacer, and a part of the cavity surface is formed. In the apparatus for manufacturing a cast polyamide resin molded article in which a corner portion of a spacer to be formed is a tapered surface with respect to a side plate surface, the corner portion of the spacer forming a part of the cavity surface is tapered at a predetermined angle with respect to the side plate surface. The surface makes it possible to prevent shrinkage of the molded body due to pinching of burrs, so that the molded body can be freely shrunk, and voids near the spacers and surface sinks in the thickness direction can be reduced. Camphor can be.

According to a second aspect of the present invention, there is provided an apparatus for manufacturing a cast polyamide resin molded article in which at least one of the side panels is movable, and a spacer is sandwiched and fixed so as to be opened.

[0007] In the invention according to claim 3 of the present application, at least one of the pair of side panels, at least one of which can be moved and the temperature of which can be adjusted, is at least one of which can adjust the temperature.
More than one middle board is arranged, a spacer is interposed between each pair of side boards and the middle board, one side board is moved to the other side board, and each board and spacer are integrally clamped and fixed And forming a cavity for casting a polymerizable lactam liquid. With this device, the molded product can be freely shrunk, and not only can voids near the spacers and surface sinks in the thickness direction be eliminated,
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 article having a large thickness and having no cavity defects. In addition, temperature control and temperature control of the mold from the time of casting the polymerizable lactam liquid to the time of 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 contract.

According to a fifth aspect of the present invention, there is provided a method for manufacturing a cast polyamide resin molded article, wherein the spacer is a frame having one side open, and the frame has a passage for flowing the heat transfer oil. is there.

[0010]

FIG. 1 is a front view of an apparatus for producing a cast polyamide resin molded article according to the present invention, FIG. 2 is a plan view showing a state of molding in FIG. 1, and FIG. 3 is a production view shown in FIG. FIG. 4 is a front view of a spacer, FIG. 4 is a front view of a spacer, FIG. 5 is a sectional view taken along line AA of FIG. 2, and FIG. 6 is an enlarged view of a portion B of FIG.

An apparatus 1 for manufacturing a cast polyamide resin molded article according to the present invention comprises: a fixed member 2 having a side plate 4 mounted thereon; It comprises a spacer 5 interposed between members 3 to form a cavity 7, and a heat medium oil circulation device 6.

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

As shown in FIG. 3, the side panel 4 is a hollow body made of a metal plate such as aluminum or iron. And
An oil passage 16 is provided for communicating the heat transfer oil. When the heat medium oil enters from an oil port 17 provided on the lower side of the side panel 4, it flows through a communicating oil path 16, and is discharged from an oil outlet 18 provided on the upper side while uniformly heating the inside of the side panel 4. Via the pipe 19 to the heat medium oil circulating device 6 and circulates therebetween.

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

As shown in FIG. 4, the spacer 5 is a U-shaped frame having one side open, and a through hole 25 for passing a bolt at a constant interval is provided on each side. An oil passage (not shown) through which the heat medium oil passes is provided inside the frame body. The heat medium oil passes through an oil passage from an oil port 27 provided on the lower side and exits an 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 moving member 3
And mechanically fixed. However, spacer 5
In order to increase the sealing effect between the spacer 5 and the side panel 4, a packing 30 made of a rubber elastic material such as urethane or silicon rubber may be attached to both surfaces of the frame 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 medium oil circulation device 6 includes a heating device for heating the heat medium oil put in the tank and a pump for circulating the heat medium oil. It is connected to the mounted side panel 4 and the spacer 5.

In the apparatus of the present invention, a pair of side panels 4 may be fixed, and a cavity 7 may be formed with a spacer 5 interposed therebetween. Of course, each side panel 4,
The temperature of the heat transfer medium 4 and the spacer 5 can be adjusted by the heat medium oil circulation device 6. Further, a pair of side panels 4 which can be adjusted in temperature,
4, at least one or more middle panels (not shown) capable of controlling the temperature are arranged, a spacer is interposed between the pair of side panels 4 and each panel including the middle panel, and one side panel 4 is provided. May be moved to the other side panel 4, and the plurality of cavities 7 may be formed by integrally clamping and fixing each panel and the spacer 5.

According to the present invention, as shown in FIGS. 5 and 6, a packing 30 for preventing leakage of the polymerizable lactam liquid is interposed between the pair of side panels 4, 4 and the spacer 5, and the cavity surface is provided. A corner portion 32 of the spacer 5 forming a part of the base 31 has a tapered surface 34 having an angle θ of 10 to 50 degrees with respect to the side panel surface 33. For this reason,
The inhibition of shrinkage of the molded body due to pinching of burrs is eliminated,
The molded body can freely shrink, and voids near the spacer 5 and surface sinks in the thickness direction can be eliminated.

If the angle θ of the tapered surface 34 is less than 10 degrees, the shrinkage of the molded body is hindered, so that voids near the spacer 5 and surface sinks in the thickness direction are liable to occur. Is exceeded, the wall strength of the packing groove 35 decreases, and this portion is easily deformed during use. Further, a release agent such as silicone oil can be applied to the tapered surface 34 in order to freely shrink the molded body.

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, a 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 attached to the fixed member 2, and then the moving member 3 is moved to separate the spacer 5 into two. A cavity 7 for casting the polymerizable lactam liquid is formed between the side plates 4 and 4. At this time, the spacer 5 and the two side plates 4 and 4 are mechanically fixed by bolts or clamps instead of the bolts.
Temperature and preheat.

Thereafter, the polymerizable lactam solution is added to the cavity 7
And anionically polymerized 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 panels 4, 4, the moving member 3 is moved to the original position. The obtained cast polyamide resin molded article can be easily removed from the mold. The molded body can be freely shrunk, and voids near the spacer and surface sinks in the thickness direction can be eliminated.

The polymerizable lactam solution is obtained by adding an anionic polymerization catalyst and an anionic polymerization initiator to ω-lactam, and the ω-lactam is substantially anhydrous α-piperidone, ε-caprolactam, ω-lauro. Lactam or a mixture of two or more of these, 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. 1 to 2.0 mol%. And, as the initiator for anionic polymerization, for example, N-acetyl-ε-caprolactam, isocyanate,
Diisocyanates, urea derivatives, urethanes, and isocyanurate derivatives, and the added amount thereof is preferably in the range of 0.05 to 1.0 mol% based on ω-lactam.

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

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

[0026]

As described above, in the invention described in each claim of the present application, a packing for preventing leakage of the polymerizable lactam liquid is interposed between the side plate and the spacer, and a part of the cavity surface is formed. In the apparatus for manufacturing a cast polyamide resin molded article in which the corner portion of the spacer to be formed is tapered with respect to the side plate surface, the corner portion of the spacer forming a part of the cavity surface is tapered at a predetermined angle with respect to the side plate surface. By doing so, the inhibition of shrinkage of the molded body due to pinching of burrs is eliminated, and the molded body can be freely shrunk, which has the effect of eliminating voids near the spacer and surface sinks in the thickness direction.

[Brief description of the drawings]

FIG. 1 is a front view of an apparatus for producing a cast polyamide resin molded article 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.

FIG. 5 is a sectional view taken along line AA of FIG. 2;

FIG. 6 is an enlarged view of a portion B in FIG. 5;

FIG. 7 is a sectional view of a mold used in a conventional apparatus for manufacturing a cast polyamide resin molded article.

[Explanation of symbols]

 2 Fixed member 3 Moving member 4 Side panel 5 Spacer 7 Cavity 30 Packing 32 Corner part 33 Side panel surface 34 Tapered surface 35 Packing groove

Claims (5)

[Claims] A cavity is formed between a pair of side panels with a spacer interposed therebetween, and a polymerizable lactam solution is cast into the cavity and anion-polymerized to form a cast polyamide resin plate. In the apparatus to be manufactured, packing for preventing leakage of the polymerizable lactam liquid was interposed between the side plate and the spacer, and the corner portion of the spacer forming a part of the cavity surface was tapered with respect to the side plate surface. An apparatus for producing a cast polyamide resin molded product, 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 or more middle panels whose temperature can be adjusted are arranged between a pair of side panels whose temperature can be adjusted while at least one of them can be moved. A spacer is interposed between each panel, and one side panel is moved to the other side panel, and each panel and the spacer are integrally sandwiched and fixed to form a cavity for casting a polymerizable lactam liquid. Item 2. An apparatus for producing a cast polyamide resin molded article according to Item 1. 4. The angle of a tapered surface formed at a corner of a spacer is 10 to 50 degrees.
An apparatus for producing the cast polyamide resin molded article according to the above. 5. A frame body in which the spacer is open on one side,
4. The device according to claim 3, further comprising a passage through which the heat medium oil flows in the frame.
Or an apparatus for producing a cast polyamide resin molded article according to 4.