JPS60189411A - Mold assembly - Google Patents

Abstract

PURPOSE:To make a flow of resin into a well-ballanced state, by a method wherein a movable shaft is incorporated into a runner part of a gate part and a cross-sectional area of the runner is varied freely from the outside of a mold by interlocking a rotary driving shaft with the movable shaft. CONSTITUTION:Injected resin passes through a runner 2 from a sprue bushing 13 and flows in each cavity from a gate. In this instance, as for adjusting action in case of dealy in filling a plurality of pieces of cavities 1b with the resin as compared with that of a plurality of pieces of cavities 1a, when a rotary shaft 20 of a gate balance unit 23a of a cavity 1a side whose filling is early is driven by a handle 24 from the outside of the mold, the rotary shaft connected with a screw block 21 secured to a main body makes a movable shaft 19 advance and a quantity of a flow of the resin delay. The titled mold assembly, therefore, can correspond immediately in the midst of molding and microscopic adjustment also becomes easy.

Description

[Detailed description of the invention] Industrial applications.

The present invention uses gate balance to uniformly fill resin into multiple cavities during precision injection molding.

This relates to a mold device for molding.

The structure of the conventional example and its problems The conventional gate balance has molded parts (cavities) 1-a and 1- as the specific structure is shown in FIGS. 1 and 2.
In order to balance the flow of resin in b, the resin flowing from runner 2 is squeezed in advance at the entrance of the cavity as shown in 2-c, and the mold is closed as shown in gate 2-d of the cavity where the flow is slow. Expand by scraping or gate thickness f
The method used was to set it small like 2-e and enlarge it like 2-f.

However, with the above method, in order to balance the filling of resin into the cavity during the molding process, it is necessary to remove the mold from the molding machine and scrape off the gate in the cavity where the flow is slow. It takes a lot of time and effort to balance the individual cavities, which has the disadvantage of delaying the start of mass production.

Purpose of the Invention In view of the above-mentioned drawbacks, the present invention provides a method for forming a plurality of 3.
.

To provide a mold device that quickly and accurately balances resin filling into a cavity without removing the mold from a molding machine.

Structure of the Invention The mold device of the present invention incorporates a moving shaft for restricting the flow rate of resin in the runner (runner) section in front of the gate section of a plurality of cavities, and allows manual or automatic (not shown) operation from outside the mold. The cross-sectional area of the runner can be freely changed by interlocking the rotational drive and the moving axis, and the cross-sectional area of the runner can be changed freely depending on the filling state of the cavity during the molding process when the mold is attached to the molding machine. It has the unique effect of being able to balance the flow of resin at the appropriate time and quickly responding to mass production of precision molded products.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings. In Fig. 3, 1a is the cavity, 3 is the fixed side mounting plate, 4 is the fixed side mold plate that holds the cavity insert, 5 is the movable side template that holds the movable side insert, and 6 is the movable side insert surface. 7 is the protrusion pin of the runner, 8 is the spacer block, 9.10 is the ejector plate that holds the runner and the protrusion pin of the molded product, 11 is the ejector plate that protrudes the movable insert, 12 is the Movable side mounting plate, 13
1411″j is a sprue bush, 1411″j is a support that holds the pressure by passing the pressure on the movable side through the receiving plate, 15 is a connecting bolt that connects the movable side insert 18 and the ejector plate 9, and 16 is an ejector turbine that projects the molded product. , 17 is an insert on the fixed side.

In Figures 4, 5, 6, and 7, 19 is a moving shaft that controls the flow of resin in a part of the runner, and 2° is connected to the aforementioned moving shaft, and the moving axis moves back and forth from rotational motion. A rotating shaft to be slid, 21 a screw block engaged with the rotating shaft and fixed to the main body, 22 a locking nut, and 23 a unit main body for integrating the gate balance section.

The operation of the mold device configured as described above will be described below.

5 Vane First, the resin injected from the molding machine sprue bushes 13
Pass through Runner 2 from Game) 2-c.

Resin flows into each cavity from 2-d. At this time, the flow balance of multiple cavities is disrupted, and if the filling of the resin is delayed compared to 1-a, the adjustment operation is to fill quickly. When the rotating shaft 2o of the gate balance unit 23-a on the side of the cavity 1-a is driven by the nondle 24 from the outside of the mold, the rotating shaft that is engaged with the screw block 1 fixed to the main body will be driven by the thickness of the runner 2. The moving shaft 19 intersecting the runner at the same height is advanced, narrowing the cross section of the runner and slowing down the flow rate of the resin. Through the above operation, the gate balance is completed and when the optimum condition is reached, tighten the locking nut 22 and move the moving shaft 19.
to be fixed. Next, after a certain amount of cooling of the filled molded products, the mold opening process begins, and the ejector plate 1
3 and the bolt 16 set on the movable insert 18, the molded product is projected out of the mold while being in close contact with the movable insert. Furthermore, the movable side insert is tightly attached to the 61
, 7 The molded product is separated from the movable insert by the ejector turbine 16 incorporated in the ejector plates 8 and 9, and the molded product is completely taken out of the mold and entered into the next cycle.

As described above, according to this embodiment, unlike the conventional example, there is no need to remove the mold from the molding machine in order to balance the gate, and it is not necessary to take the trouble of repeatedly cutting the mold body. Not only can we respond immediately, but we can also easily make fine adjustments, so we can quickly secure precision molded products.

Effects of the Invention As described above, the mold device of the present invention maintains the molding state by providing a gate balance unit at the front of each cavity to balance the resin filling of a plurality of cavities, while maintaining precision from the outside of the mold. The severe gate balance required for molded products can be performed easily and accurately at an early stage, which has great practical effects.

[Brief explanation of drawings]

FIG. 1 is a plan view showing a conventional gate balance, 7 vanes FIG. In the overall view of Part 1, the gate balance unit (D) is a partial cross-sectional view, Figure 5 is a cross-sectional view, Figure 6 is a detailed cross-sectional view of the unit viewed from the plane, Fig. 7 is a detailed longitudinal cross-sectional view. 2-c...Gate width, 2-e...Gate thickness, 23-b...Kate balance unit, 24...
····handle. Name of agent Patent attorney Toshio Nakao and one other person

Claims (2)

[Claims] (1) The flow rate is regulated in the multiple cavities, the runner in the mold until the resin injected from a separate molding machine is filled into the cavities, and the front part of the gate where the resin flows into each cavity. A mold device that includes a flow rate adjustment mechanism and a starter that operates the flow rate adjustment mechanism from the outer periphery of the mold. (2) The flow rate adjustment mechanism has a moving shaft that is at the same height as the runner and can slide in the phase change direction with the runner, and a threaded part that is connected to this moving shaft and can move in the axial direction by rotation. The mold device according to claim 1, comprising a rotating shaft and a fixed block that is connected to the rotating shaft through a threaded portion.