JPH0641154B2 - Sprue cutting device - Google Patents

Description

TECHNICAL FIELD The present invention relates to an apparatus for cutting and removing a sprue part of a molded product molded by injection molding means.

[Conventional technology]

In injection molding of thermoplastic synthetic resin products, sprues, runners, gates, etc. are usually used as resin passages to the mold cavity, but the resin solidified here is also molded in a state associated with the molded product body. In order to obtain the final product, the part (hereinafter simply referred to as sprue) must be cut and removed from the main body after being taken out from the mold. Usually cut by hand with a nipper, knife, etc.,
Various methods and devices have been proposed for cutting a molded product when it is ejected from a mold or when the mold is opened.

The method of cutting with a nipper or the like requires a cooling and curing time until cutting, resulting in poor manufacturing efficiency. Further, the latter method of automatically performing the process when the mold is removed from the mold shortens the molding cycle but complicates the mold structure and apparatus, and is not preferable especially for large-sized molded products such as pallets.

[Problems to be Solved by the Invention]

Under these circumstances, sprues are large in the case of large-sized molded products, so after removing the molded product from the molding die, fix it on a fixing device and place the cutter at the position corresponding to the sprue along the surface of the molded product. It is preferable to slide and cut from the root of the sprue. However, since the sprue is large and the number of sprue is large and the root is thick, a strong force is required for cutting, so that the blade of the cutter is easily damaged and the cut sprue is scattered.

The object of the present invention is to solve such problems, reduce mechanical force, extend the life of the cutter blade, and smoothly and efficiently remove sprue, and are particularly suitable for processing large molded products. To provide.

[Means for Solving the Problems]

That is, according to the present invention, a product molded by an ordinary injection molding apparatus is fixed to a fixed base as it is, and a sprue part is formed by sliding a cutter along the surface of the molded product at a position corresponding to the sprue part of the molded product. In the device for cutting and removing, the sprue pressing member (9) is provided on the mount (5a) of the cutter blade (5) slightly below the cutting edge line of the cutter blade (5) to provide the above-mentioned object. Has been achieved.

The fixed base of the molded product is usually fixed horizontally with the sprue side of the molded product as the lower surface, and the cutter device is arranged on the lower surface. The cutter device has a cutter blade fixed to the upper surface of a mounting base (5a) that moves horizontally along the lower surface of the molded product, and the sprue protruding on the lower surface of the molded product is cut by the movement. There is.

In the present invention, a sprue pressing member (9) is provided on the table (5a) to which the cutter blade is attached, and the pressing member (9) is located at the center of the sprue before the cutter blade contacts the root of the sprue. Set to the position where it abuts on the tip. That is, when the cutting edge comes into contact with the root of the sprue and is cut,
The sprue is bent in the direction of movement of the cutting edge, and it is essential that cutting is performed in this state. A plurality of the pressing members (9) may be provided so as to correspond to the individual sprues, but if the rod-shaped member is provided in parallel with the line of the cutting edge of the cutter, one pressing member may be provided for each of the plurality of sprues that are present side by side. The rod-shaped bodies can act simultaneously. Note that the member is not limited to the rod-shaped body, and a member having an appropriate shape may be provided so as to project.

Cutter mount (5a) is a cylinder for driving the cutter (7)
It is preferable that it is mounted so as to be adjustable up and down through a cylinder (8).

As the injection-molded product targeted by the present invention, large-sized molded products such as pallets, crates, containers and containers are advantageous. Further, such molded products are commercialized in the form of bulk molded products made of polyethylene, polypropylene, polystyrene, ABS resin or the like, low foam molded products, high foam molded products, and filler-containing molded products.

[Action]

Since it is configured as described above, the injection-molded product (1) fixed to the fixing base (2) along the surface on which the sprue exists, as shown in FIG. 1, toward the sprue (1a), Mounting base
When the cutter composed of the cutter blade (5) attached to (5a) is slid by the drive cylinder (7),
First, the pressing member (9) provided on the mounting base (5a) is a sprue.
It contacts below (1a). When the cutter further advances, the pressing member (9) gradually bends the sprue (1a) in the advancing direction of the cutter into a curved state, and a force to push it forward is exerted. At this time, the cutting edge of the cutter blade (5) is sprue
It reaches the root of (1a) and is then cut. In this way, since the root is cut from the rear in a state in which the sprue is bent forward, the force on the cutting edge is significantly reduced as compared with the case where a cutter blade is used without a pressing member to strongly cut the sprue. At the same time, the impact at the time of cutting is mitigated, and the cutting and separation are performed naturally, so that the phenomenon that the cut sprue scatters vigorously is prevented.

〔Example〕

Explaining a specific embodiment by exemplifying it in the drawings, FIG. 1 is a side view showing an essential part of the device of the present invention. Reference numeral 1 denotes an injection molded product, which is a pallet in this case, 1a is a sprue portion thereof, 2 is a pedestal for fixing the molded product, and the molded product 1 placed on the pedestal is formed by a holding tool 3 and a holding plate 4. Fixed from the side and above. A cutter blade 5 is fixed to the upper surface of the mounting base 5a, and the mounting base 5a is connected to a mounting portion 6 of a cylinder 7 which is driven in the horizontal direction to cut the sprue 1a.

The cutter mounting base 5a and the mounting portion 6 may be connected by ordinary fixing means, but if they are connected via the cylinder 8 as shown in the drawing, the proximity adjustment to the upper molded product 1 is easy. Reference numeral 9 denotes a sprue pressing member provided on the cutter blade mounting base 5a, which is provided slightly ahead of the cutting edge of the cutter blade 5 and in contact with the center or tip of the sprue 1a in the longitudinal direction. In this example, as shown in the front view of FIG. 2, the rod-shaped body is provided in parallel with the cutting edge of the cutter blade. When the pressing member 9 is fixed, it is preferable that the position can be changed and adjusted each time according to the size of the sprue. For example, in FIG.
It is preferable that the front and rear can be adjusted in FIG. Reference numeral 10 is a cooling air blowing pipe, which is particularly effective for cooling when the cutter blade after cutting is kept in close contact with the main body side cut of the molded product when applied to sprue cutting of the foamed molded product.

〔The invention's effect〕

According to the present invention, since the sprue is cut from the rear while being bent forward, the mechanical force at the time of cutting is reduced, the life of the cutter blade is extended, and the impact at the time of cutting is mitigated. Since the cut sprue is smoothly cut without spattering, it is extremely useful especially for pallets and other large-sized molded products.

[Brief description of drawings]

FIG. 1 is a side view of a main part in an embodiment of the present invention, and FIG.
The figure is a front view of the cutter blade mounting portion. 1 …… Injection molded product, 1a …… Molded product sprue part 2 …… Molded product fixing base 3.4 …… Holder 5 …… Cutter blade 7 …… Cutter drive cylinder 9 …… Sprue pressing member 10… ... Blowing pipe for cooling air

Claims (1)

[Claims] Claim: What is claimed is: 1. An apparatus for fixing an injection-molded article, and cutting and removing the sprue section by sliding a cutter along the surface of the molded article at a position corresponding to the sprue section of the molded article. A sprue cutting device for injection-molded articles, characterized in that a sprue pressing member (9) is provided on the mounting base (5a) slightly below the cutting edge line of the cutter blade (5).