JPH06335925A - Plastic molded item and method for finishing the same - Google Patents

Abstract

PURPOSE:To provide a plastic molded item and a method for finishing the same wherein the workability and finishing accuracy are excellent and the gloss is not developed on the guide butting face and a corner part is made into an R face or a C face, if it is necessary. CONSTITUTION:Parting burrs produced by a parting line P.L of a mold are cut and removed. The ridge part of a product is made to coincide with the parting lines P.L and the parting burrs are completely removed and a channel is formed. A guide is constituted of a resin raw material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plastic molded article which is finished in a good appearance by cutting a parting burr generated by a parting line of a plastic molding die and a finishing method thereof.

[0002]

2. Description of the Related Art FIG. 10 is a structural diagram of a conventional plastic molded product at the time of finishing.

A plastic molded product 1 is movably placed on a table 2, and one side face (right end face) is abutted against a metal guide 4 of a chamfering finisher 3. Further, the chamfering and finishing machine 3 has an electric cutter 5 on the upper portion of the guide 4 which rotates about an axis.

Generally, most of the parting is formed on a corner portion, and when cutting off a parting burr generated here, as shown in FIG. 10, a cap-shaped cutter 5 is faced to the corner portion to form a plastic molding. While the product 1 is abutted on the guide 4, the shade cutter 5 is rotated to chamfer the corner portion.

Regarding the technique for removing the burrs generated at the corners by using the cap-like cutter, see Japanese Utility Model Laid-Open No. 64-4623.
There is a gazette.

[0006]

However, in the plastic molded product in which the parting burrs applied to the corners are cut off and the finishing method thereof, the deburring surface at the corners becomes thicker or thinner, Since it is a particularly prominent part, it did not look good. Further, the corner portion is not formed, but has a chamfered finish (C-face finish) with cutting, which is disadvantageous in that a curved surface (R-face) which is excellent in touch and the like and which is aesthetically superior cannot be formed.

Further, in the conventional guide, since the width of the contact surface with the plastic molded product is narrow, the stability of the contact surface is poor, there is a problem in finishing accuracy, and the working efficiency is poor. Further, stress concentrates on that portion, and since it is made of metal and has high hardness, there is a problem that gloss is generated at the guide abutting portion of the plastic molded product, which impairs aesthetics.

The present invention has been made in view of such a background, is excellent in workability and finishing accuracy, eliminates the gloss of the guide abutting surface, and further rounds the corner portion if necessary.
An object of the present invention is to provide a plastic molded article which can be a surface or a C surface and a finishing method thereof.

[0009]

In order to achieve the above object, the invention according to claim 1 is such that a parting burr generated by a parting line of a molding die is cut off by a flat rotary blade. The invention according to claim 2 is
The parting line of the mold is made to coincide with the ridge line portion formed by the tapered surface and the tapered surface or another finished surface.

According to the third aspect of the invention, the parting burr generated by the parting line of the molding die is cut off with a flat rotary blade.

According to a fourth aspect of the present invention, the ridge line portion formed by the tapered surface and the tapered surface or other finished surface is formed by a forming die having a parting line of the forming die, and the ridge line portion is formed. The parting burr that occurs is removed.

According to the invention of claim 5, in the invention of claim 4, the parting burr is cut off so as to form a groove with a flat rotary blade.

According to the invention of claim 6, in the invention of claim 4, the tapered surface is brought into contact with and guided by a guide made of a resin material.

[0014]

In the present invention, since the flat rotary blade has a constant blade width and is narrow and can be cut along the parting burr, even if the parting burr is formed into a flat surface, a concave surface or a convex surface, it can be cut off with a good appearance. Since the finished surface comes off the corner, C and R surfaces as formed can be formed. Since the parting line of the molding die coincides with the ridge portion, a parting burr is generated here, and the burr can be easily removed. Finishing to the extent that grooves can be made with a flat rotary blade gives a uniform width and good appearance.

By matching the taper of the side surface of the plastic molded product and the taper of the guide so that they are in wide surface contact, the burr of the parting line formed on the part other than the corner portion is surely guided in the state where the plastic molded product is guided. To remove.

At this time, if it is desired to finish the corner portion with the R surface, a parting line may be formed at the end of the R surface. Similarly, if it is desired to finish the C-face of the corner by molding, a parting line may be formed at the end of the C-face.

[0017]

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

FIG. 1 is a longitudinal sectional view of a main part of a plastic molded product formed so that the parting line of the mold is located at the end of the R surface, and FIG. 2 is such that the parting line of the mold is located at the end of the C surface. And FIG. 3 is a similar view formed so that the parting line of the molding die is located at the connection point of the two tapers.

As shown in FIG. 1, a tapered surface 1a is formed on one side surface of a plastic molded product 1 made by blow molding, injection molding or the like at an angle θ, and the tapered surface 1a and the lower corner are formed. The parting line P. of the mold is formed on the ridge portion formed by the R surface 1b formed on the portion. It is formed so that L matches. 6 is a parting burr,
Depending on the type of molding, such as blow molding or injection molding, it is one that continues on the ridge line in a strip shape at the root of the figure, and a large part is made on it as shown in the figure.

Further, in FIG. 2, a tapered surface 1a,
The parting line P. of the forming die is formed on the ridgeline formed by the C surface 1c formed on the lower corner. It is formed so that L matches.

Further, in FIG. 3, two tapered surfaces 1a, 1a symmetrically provided with a vertical center line therebetween are provided.
At the ridge line portion (taper apex) formed by the above, that is, at the upper and lower center positions. It is formed so that L matches.

As described above, in the present invention, the parting line P. L is the tapered surface 1a and the tapered surface 1
It is formed so as to coincide with the ridge line portion formed by a or the other finished surfaces 1b, 1c.

FIG. 4 is a block diagram of the plastic molded product shown in FIG. 1 during finishing.

The guide 7 is made of a resin material having a low hardness, has the same inclination angle as the taper surface 1a of the plastic molded product 1, and is a taper surface which makes a wide range of surface contact with the taper surface 1a. 7a. Further, the flat rotary blade 8 having teeth on its disk-shaped peripheral side surface is arranged below the tapered surface 7 a of the guide 7 so as to be vertically movable.

With such a structure, at the time of finishing, the plastic molded product 1 on the table 2 is the same as described above.
The taper surface 1a of the guide 7 is abutted against the taper surface 7a of the guide 7 for positioning, and the flat rotary blade 8 is moved up and down to move the parting line P.P. By moving along the L, the parting burr 6 at the end of the R surface 1b is cut off while moving the plastic molded product 1. When the R surface 1b is formed at the corner of the plastic molded product 1 used for a storage case of equipment, the touch surface has a better feel than the C surface 1c.

Similarly, as shown in FIG. 3, the tapered surfaces 1a,
Also when cutting the parting burr 6 formed at the apex of the lathe 1a, as shown in FIG. 5, the tapered surface 1a and the tapered surface 7a are butted against each other and the flat rotary blade 8 is moved upward to move the parting line P.I. According to L, the parting burr 6 is removed while the plastic molded product 1 is moved by the guide of the guide 7.

In the above description, the parting burr 6
The case was described in which the ridges are formed on the bulging portion (convex surface) such as tapered surfaces. Needless to say, if the flat rotary blade 8 is used, it is possible to cut even a valley portion or a flat surface portion having a slight concave surface.

The chips falling down are absorbed by a dust collector (not shown).

FIG. 6 is a diagram showing the construction of a plastic molded product having irregularities at the time of finishing.

When the lower surface of the plastic molded product 1 has irregularities as described above, the tray 9 fitted to a part of the shape is formed.
Is movably placed on the table 2, the plastic molded product 1 is stably held by the tray 9, and finishing processing is performed in the same manner as described above.

FIG. 7 is an overall perspective view of a plastic molded product during finishing.

For example, the taper surface 1a of the plastic molded product 1 is pressed against a guide 7 fixed on the table 2 to slide, and the flat rotary blade 8 has a parting line P in a fixed relationship with the guide 7. ． Move on L and remove the parting burr. The flat rotary blade 8 is driven by a motor 10 arranged below the table 2, and the motor 1 fixed to the table 2
0 is stored in the motor cover 11. A dust collecting duct 12 is formed on the side of the motor cover 11 so that the above-mentioned chips can be sucked to the outside. Here, the guide 7 is hollow, a peripheral wall thereof has a window (not shown), and the blade of the flat rotary blade 8 is projected from this window.

FIG. 8 is a vertical cross-sectional view of a main part of a plastic molded product showing a state where the depth of the finished surface up to the width of the flat rotary blade 8 is zero, and FIG. 9 is a state where the depth of the finished surface is negative (from the surface). It is a principal part longitudinal cross-sectional view of a plastic molded product showing a state in which the finished surface has been bitten inward.

As shown in FIG. 8, the finished surface after the burr is cut off becomes the blade width of the flat rotary blade 8 and becomes a smooth side surface by the both tapered surfaces 1a. From the viewpoint of the processing accuracy and the relationship with the guide 7, the finishing surface may be slightly indented as shown in FIG. In such a case, if the width of the flat rotary blade 8 is narrowed (for example, about 2 to 2.5 mm), the groove 13 caused by the biting of the finished surface can be made inconspicuous in appearance. The groove 13 can be used as a molding mounting groove.

Further, since no special structure is adopted for carrying out the finishing method of this embodiment, the structure can be made inexpensive and the structure with less burr scattering.

As the plastic molded product, there are the storage case of the above-mentioned equipment and the feet of the electronic piano.

The plastic molded product 1 is formed by blow molding in which a parison is formed between a pair of molds and air is blown when the mold is closed, but it may be molded by injection molding. At this time, the mold alignment position is the parting line P. Parting Bali 6 with L
Is formed. The parting burr 6 is cut off in the same manner as described above.

[0038]

As described above, claims 1 and 3
According to the invention, since the parting burr is cut off by the flat rotary blade, it is possible to provide a product in which only the burr that has to be removed is cut off in a good appearance. According to the inventions of claims 2 and 4, since the finished surface is located outside the corner, the R surface and C surface can be obtained as they are molded, and the feel and aesthetics are excellent, and the finished surface has a good appearance. Moreover, since it is on the ridgeline, the workability of deburring is good.

According to the invention of claim 5 in which the groove is formed, the width of the cutting surface for burr excision becomes uniform and the appearance is improved,
Further, by using the groove as a molding mounting groove, it is possible to upgrade.

According to the invention of claim 6 in which the guide is made of a resin material, no scratch or change in gloss is given to the molded product.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view of a main part of a plastic molded product formed so that a parting line of a molding die is aligned with an end of an R surface.

FIG. 2 is a vertical cross-sectional view of a main part of a plastic molded product formed so that a parting line of a molding die is aligned with a C-plane end.

FIG. 3 is a longitudinal sectional view of a main part of a plastic molded product formed so that a parting line of a molding die is aligned with a connection point of two tapers.

FIG. 4 is a configuration diagram of the plastic molded product shown in FIG. 1 during finishing.

5 is a configuration diagram of the plastic molded product shown in FIG. 3 during finishing.

FIG. 6 is a configuration diagram at the time of finishing processing of a plastic molded product having irregularities.

FIG. 7 is an overall perspective view of a plastic molded product during finishing.

FIG. 8 is a longitudinal cross-sectional view of a main part of a plastic molded product showing a state where the finished surface has a depth of zero.

FIG. 9 is a longitudinal cross-sectional view of a main part of a plastic molded product showing a state where the finished surface is a groove.

FIG. 10 is a configuration diagram at the time of finishing processing of a plastic molded product according to a conventional example.

[Explanation of symbols]

 1 Plastic molded product 1a Tapered surface 2 Table 6 Parting burr 7 Guide 8 Flat rotary blade P. L parting line

Claims (6)

[Claims] 1. A plastic molded product, wherein a parting burr generated by a parting line of a molding die is cut off with a flat rotary blade. 2. The plastic molded product according to claim 1, wherein a parting line of the molding die is aligned with a ridge line portion formed by the tapered surface and the tapered surface or another finished surface. 3. A method for finishing a plastic molded product, characterized by cutting off a parting burr generated by a parting line of a molding die with a flat rotary blade. 4. A molding die in which a parting line of the molding die coincides with a ridge portion formed by a tapered surface and a tapered surface or another finished surface, and a parting burr generated on the ridge portion is cut off. 4. The method according to claim 3, wherein
A method for finishing a plastic molded article as described. 5. The method for finishing a plastic molded product according to claim 4, wherein the parting burr is cut off so as to form a groove with a flat rotary blade. 6. The method for finishing a plastic molded product according to claim 4, wherein the tapered surface is brought into contact with and guided by a guide made of a resin material.