JPS6232822Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The disclosed technology belongs to a technical field in which an undercut portion is formed during injection molding.

This invention relates to a mold structure in which a slide core facing a cavity formed by clamping forms an irregularly shaped part such as an undercut on a molded product, and in particular,
A fixed mold is supported by a stopper on a locking block fixed to an inclined pin that moves the slide core by concave-convex fitting, while the slide core is made to be slidably connected to the movable mold via a spring. and a locking block with mutually slidable sloped surfaces, so that when the mold is opened, the slide core follows and retreats as the movable mold moves. It is an idea.

<Prior Art> As is well known, for example, when injection molding is used to mold a molded product having a U-shaped cross section as shown in FIG. From this point of view, it is generally done at the same time as molding.

Conventionally, as shown in FIG. 2, a mold 5 consisting of a movable mold 3 and a fixed mold 4 is clamped, and a molten resin is injected into a cavity 6 formed. When the movable mold 3 is lowered to open the mold after solidification, the hole 2 on the end side surface follows.
A slide core 8 having a protrusion 7 at its tip that forms a
As the movable mold 3 descends, the movable mold 3 slides onto a pin 9 projecting obliquely from the fixed mold 4 and retreats, and is moved back to a connecting rod 11 equipped with an elastic spring 10 as a rear ammunition. I am drawn back.

Therefore, the protrusion 7 is separated from the cavity 6, and the molded product 1 in which the hole 2 is formed can be taken out.

<Problems to be solved by the invention> By the way, in the fixed mold 4, the tap hole of the screwing part must be drilled diagonally by the inclination of the pin 9.
There are disadvantages in that positioning during machining is cumbersome, increases the number of setup steps, increases mold manufacturing costs, and requires skill in machining.

Furthermore, if the pin 9 is unexpectedly deformed by external force during operation, the threaded part will naturally be damaged, so it is not possible to replace only the pin 9, and as a result, the mold The inconvenience was that the whole thing needed to be repaired.

On the other hand, a connecting rod 11 provided with an elastic spring 10
Since it is provided at the rear of the slide core 8 and protrudes, there is a problem that the overall space occupation rate of the mold 5 is high.

In order to deal with such problems, for example,
The device disclosed in Japanese Patent Publication No. 39-17437 was also developed, and a fixed type with an inclined guide rod that fits together.
The movable mold is installed so that it can freely slide laterally using an elastic spring, but due to repeated use over time, there is a risk that the inclined guide rod may become loose and fall off from the fixed mold due to the frequent action of clamping and opening the mold. There is a problem that there is.

In addition, because the fixed mold is separated by bolts, when the movable mold rattles due to increased injection pressure, it shifts outward, resulting in burrs and molding defects called waste in the product. There was a problem that resulted in non-defective products.

The purpose of this invention was to solve the problems of the mold structure based on the conventional technology mentioned above, and to make mold manufacturing accurate and inexpensive, maintainability and durability, and make use of limited space. The purpose of the present invention is to provide an excellent molding die structure that can be utilized in the field of molding technology in the machinery parts manufacturing industry.

<Means/effects for solving the problem> In accordance with the above-mentioned purpose, the structure of this invention, which is summarized in the above-mentioned utility model registration claims, is such that the inclined pin is supported via a stopper in order to solve the above-mentioned problem. The locking block of the fixed type has a positioning part with a concave-convex fitting type, and is attached removably based on this as a reference.On the other hand, the movable type has a slide core with a hole through which an inclined pin is inserted through an elastic machine. Put it on,
In the mold-clamped state, the tilted pin, the tilted surface of the locking block inside the tilted pin, and the slide core are positioned by the tilted surface, and the tip protrusion is held in the cavity against the bullet. It is a technical measure that makes it possible to face the situation.

<Example> Next, an example of this invention will be described with reference to FIG.
The explanation will be as follows based on FIGS. 3 and 4.

Reference numeral 5' denotes an injection mold as a molding mold which forms the center of the gist of this invention, and a locking block 14 fixed with a bolt 13 to a fixed mold 12 vertically mounted on a frame (not shown) is connected to the fixed mold. The positioning part on the 12 side and the convex part 14' as a positioning part opposite to the recessed part 12' as a slip prevention part are fitted, and the slope is formed at a set angle with the downward direction outward toward the inner end surface of the mold. An inclined pin 18 is fitted and supported in a hole 17 which is formed with a surface 15 and has a counterbore 16 in the upper part which is parallel to the tapered surface 15 in the middle.

The flange 19 at the proximal end of the inclined pin 18 is hooked to the counterbore 16 as a stopper to prevent it from falling off, and its head is held in contact with the fixed die 12, so that the shank of the inclined pin 18 at the lower part thereof is held in place. A portion is fitted into the hole 17 so as to be relatively slidable, and the tip extends downward.

On the other hand, 22 is a movable type connected to an elevating device (not shown), and forms a cavity 6 in a clamped state facing the fixed mold 12, and forms an end side surface of the molded product 1 having a U-shaped cross section as shown in FIG. hole 6' formed in
A slide core 24 with a protrusion 23 as a tip protrusion faces an elastic spring 25 as a bullet.
The movable mold 22 and the guide plates 20 on both sides thereof are sandwiched between the movable mold 22 and the guide plates 20 on both sides of the movable mold 22 so as to be slidably engaged therewith.

Further, the slide core 24 has an inclined surface 26 in surface contact with the inclined surface 15 of the locking block 14, and
An inclined pin 18 is inserted into an inclined hole 27 formed to be slidable and bored at the rear thereof.

In addition, 28 is a relief for the tip of the inclined pin 18 which is recessed in the tip of the inclined pin 18 in the cavity,
Further, 29 is a stopper that restricts the slide back of the slide core 24 at the stroke end.

In the above configuration, the inclined pin 18 is machined in advance on a lathe, and is inserted into the counterbore 16 of the locking block 14 from its tip and fitted into the hole 17 for support, and the flange 19 is attached to the counterbore 16. By attaching the locking block 14 to the fixed mold 12 with bolts 13 in the latched position, the protrusion 14' of the locking block 14 is removed.
is fitted into the recess 12' of the fixed mold 12 and positioned, while the flange 19 of the tilting pin 18 is in contact with and held by the fixed mold 12.

Then, molten resin is injected into the cavity 6 formed by clamping the mold to perform injection molding, and after molding and solidifying a predetermined molded product 1, when the movable mold 22 is lowered to open the mold, it follows the molding process. Then, the slide core 24 slides with the hole 27 and the shank of the inclined pin 18 in contact with each other, and is guided by the guide plate 20 of the slide core 24 attached to the movable mold 22, and moves laterally in the direction of the arrow. Moving.

Then, the slide core 24 is activated by the elastic spring 2.
5, the inclined surfaces 15 and 26 slide back in a state of surface pressure contact, and the protrusion 23 at the tip comes out of the hole 2 of the molded product 1, and at the lower end of the movable mold 22, the rear end It comes into contact with the stopper 29, reaches the end of the stroke, and stops moving backward.

Therefore, the molded product 1 after opening can be easily taken out.

On the other hand, if the inclined pin 18 is unexpectedly deformed or damaged during the above-mentioned molding process, the locking block 14 is removed via the bolt 13, a new inclined pin 18 is replaced outside the system, and then reinstalled. Just do it.

During repeated molding, the inclined pin 18 is fixed to the locking block 14 as a stopper via the flange 19, so that it is prevented from falling, and the locking block 14 is moved into the recess 12' of the fixed mold 12. Since the convex portion 14' is fitted and fixed by convex-concave engagement, the locking block 14 is prevented from shifting or rattling.

Then, the inclined pin 18 is connected to the locking block 1.
Since the head is internally held and held in the counterbore portion 16 of the flange 19, the vertical direction is restricted in the same way as the stopper action of the flange 19, thereby preventing play from occurring.

It goes without saying that the embodiment of this invention is not limited to the above-mentioned embodiment. For example, the tip of the inclined pin may be formed into a tapered shape to improve the fit with the slide core during mold clamping. Various embodiments can be adopted, and the target is not limited to injection molds, but may also be cast molds.

<Effects of the Invention> According to this invention, basically, in the molding die structure, the inclined pin is supported by a locking block that is fixed to the fixed die in a manner that allows it to be detached freely, so that even if unexpected deformation or damage occurs, it can be easily replaced, resulting in a significant improvement in maintainability.

In addition, there is no need to drill tapped holes in order to screw the inclined pin into the fixed mold as in the past, reducing setup and processing man-hours, and reducing mold manufacturing costs. The excellent effect of being able to do this is achieved.

Furthermore, since the locking block is fixed to the fixed mold through concave-convex fitting, it has the effect of not rattling or shifting even when the mold is repeatedly closed and opened. Even in the event of wear or unexpected damage to the tilting pin, the locking block has a kind of positioning function and can be smoothly attached to the fixed mold, which is an excellent effect.

In addition, since the head of the locking block mounted on the fixed mold is interposed with an inclined pin and is provided via a stopper such as a flange, repeated mold clamping and mold opening are not required. The effect is that the tilting pin will not fall off the locking block even if the locking block is moved.

Furthermore, since the ammunition is interposed between the movable mold and the slide core, there is an advantage that the mold can be made compact and the space obtained can be used effectively.

In addition, since the hole into which the inclined pin is fitted and the tapered surface where the slide core makes sliding contact are formed in one locking block, indexing from the reference surface during machining is easy and provides good parallelism and dimensional accuracy. It has the effect of being able to make molds.

Further, when assembling, the fixed mold and the locking block are positioned simply by fitting the positioning portions into each other, so there is an advantage that no jig or the like is required and the assembly is easy.

Therefore, depending on the design, standardization of locking blocks can provide compatibility, which in some cases can lead to a significant increase in the efficiency of the CAD/CAM system. There are also physical benefits.

[Brief explanation of the drawing]

Figure 1 is a schematic partially cutaway perspective view of a molded product with holes;
2 is a schematic partial cross-sectional view of a molding die based on the prior art, FIG. 3 is a schematic cross-sectional view of one embodiment of this invention, and FIG. 4 is a partially cutaway side view of FIG. 3. 22... Movable type, 12... Fixed type, 6... Cavity, 24... Slide core, 18... Inclined pin, 5'... Molding die, 14... Locking block, 25... Bullet machine.

Claims (1)

[Scope of utility model registration request] Molding in which a slide core provided on the movable mold is slidably inserted into a tilted pin protruding from the fixed mold so as to be freely retractable toward a cavity formed by clamping a movable mold and a fixed mold. In the mold structure, the tilting pin is supported via a stopper on a locking block that is releasably fixed to the fixed mold by a concave-convex fit, and a bullet is connected between the slide core and the movable mold. A molding die structure characterized by being interposed between.