JP2002225063A - Material supply apparatus in compression molding machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attempt the evening of material resin full in a cavity by the forward/rearward movement of a material feeder and the removal of burrs falling on a parting surface outside a mold by installing material levelling plates in the feeder. SOLUTION: An oblong material feeder 22 is installed on the lower side of a material hopper installed in parallel to a vertical mold clamping device to be freely movable forward/rearward to/from the mold clamping device. A feeder hopper 23 reciprocating between the falling port of the material hopper 21 and the cavity 12a of a lower mold 12 is installed in the material feeder 22. The material levelling plates 26 and 27 of a pair by an elastic material are fitted in front and in the rear of the feeder hopper 23 to make the rear side somewhat higher than the front side. The material levelling plate 26 on the front side is used for removing the burrs.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a material supply apparatus in a compression molding machine for compressing a thermosetting resin in a mold to form a product having a desired shape.

[0002]

A typical compression molding machine is:
A material hopper is juxtaposed to a vertical mold clamping device having a mold up and down, a horizontally long material feeder having a feeder hopper is arranged below the material hopper, and the feeder hopper is moved by moving the material feeder forward and backward. By reciprocating between the dropping port of the material hopper and the cavity of the lower mold, powdery or granular material resin is supplied to the cavity.

In such a material supply, after a feeder hopper is positioned right above a cavity, a shutter at the bottom is opened and the measured material resin in the feeder hopper is quickly dropped into the cavity. It becomes heaping and dead space is generated around it. This dead space causes unevenness of the material resin at the time of compression molding. With a material resin having a high melt viscosity, unevenness occurs in the material flow and the compression force in the cavity, and it becomes difficult to mold a product having a uniform thickness distribution. Also, a large amount of burrs is likely to occur.

Therefore, the shape of the falling port of the feeder hopper is adjusted to the opening of the cavity, and the opening speed of the shutter is increased.
When the shutter is fully opened, control is performed so that the entire amount of the metering resin falls into the cavity, and after the shutter is opened, the retreat speed of the material feeder is similarly controlled, so that the material is uniformly supplied so that it does not peak. Like that. In such a supply unit, since the opening speed of the shutter and the retreat speed of the material feeder are necessarily set to a low speed, the material supply time in the molding process is lengthened, the molding cycle time is shortened, and the productivity is improved. In order to achieve this, new means are needed to supply the material in a very short time.

In a compression molding machine, a product adheres to a core mold of an upper mold opened upward and is released, and burrs are removed upward together with the product. When the product is released from the core mold by the take-out device, the product may come into strong contact with the hanging burr, and the burr may fall on the parting surface of the lower mold. An air blow device is used as a means for removing the burrs. However, since the burrs are heavy, large burrs cannot be removed by air blow, and there are problems such as deterioration of the working environment due to rising of dust.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a material feeder provided in a conventional material supply apparatus, in which a dead space can be reduced by leveling a heap of material resin in a cavity, and a drop burr on a parting surface can be reduced. An object of the present invention is to provide a material supply device in a compression molding machine having a new configuration that can solve the above-described conventional problem by providing a material leveling plate that can be removed outside the mold.

[0007]

SUMMARY OF THE INVENTION According to the present invention, there is provided a material hopper arranged in parallel with a vertical mold clamping device having a mold at the top and bottom, and a movable lower and upper side of the material hopper with respect to the mold clamping device. And a feeder hopper provided in the material feeder and reciprocating between a drop port of the material hopper and a cavity of the lower mold. Are mounted with a slight height difference between them.

Further, according to the present invention, the pair of material leveling plates are formed of an elastic material, and the front material leveling plate is attached to the tip of the material feeder at a height in contact with the parting surface of the lower mold. That is.

In the above configuration, a pair of material leveling plates are attached to the front and rear of the material hopper of the material feeder, and the forward and backward movement of the material feeder is controlled, so that the level of the material resin dropped and injected into the cavity is leveled. Since it can be performed by the front and rear material leveling plates and the burr can be removed by the front material leveling plate, it can be immediately applied to the conventional material supply apparatus. In addition, the removal of burrs by the material leveling plate on the front side is based on the push-out due to the forward speed of the material feeder, so there is no dust soaring, and the speed of moving the material feeder is set to a high speed, shortening the time required for material supply, It is also possible to improve the molding cycle time.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the drawings, reference numeral 1 denotes a vertical mold clamping device, and 2 denotes a material supply device adjacent to the mold clamping device 1. The mold clamping device 1 includes a lower mold 12 having a normal structure having a cavity on the upper surface of a mold placing plate 11, and an upper mold 14 having a lower structure of a movable plate 13 above the lower structure having a core for compression. Is attached.

The material supply device 2 has a horizontally long material feeder 22 provided below the material hopper 21 juxtaposed to the mold clamping device 1 so as to be able to advance and retreat with respect to the mold clamping device 1. And a feeder hopper 23 that reciprocates between a drop port of the material hopper 21 and the cavity of the lower mold 12, and is disposed between a drop port of the feeder hopper 23 and the material hopper 21. Measuring device 24.

The material feeder 22 is a feeder hopper 2
A shutter opening / closing device 25 including an air cylinder for opening and closing the shutter 23a of the feeder hopper 23 and a piston rod is provided at a front portion where the shutter 3 is installed. Further, a plate made of an elastic material such as hard rubber or plastic is provided between the front and rear of the feeder hopper 23, in the figure, at the tip of the material feeder 22 and the mounting portion of the shutter opening / closing device 25.
It is attached as 6,27.

The material leveling plates 26 and 27 are provided on the front side so that the top of the material resin protruding from the parting surface of the lower mold 12 on the heap can be leveled twice back and forth. Reference numeral 26 denotes a height at which the material is slid in contact with the parting surface, and a material leveling plate 27 on the rear side is mounted at a slightly higher height with a difference in height.

Such a pair of material leveling plates 26, 2
The material feeder 22 to which the rotator 7 is attached fits the rotators 28, 28, which are attached to the front and rear and upper and lower sides on both sides of the rear part, on the guide rails 29 on both sides erected above the machine base 3 toward the mold clamping device 1. A rear end portion is connected to a slider 31 of a rodless cylinder device 30 provided in parallel on the machine base 3 between the guide rails 29, and provided on the machine base 3 so as to be able to advance and retreat with respect to the mold clamping device 1. Have been.

FIG. 3 shows the supply state of the powdery or granular material resin by the material feeder 22.
1 are omitted and shown in order. First, the feeder hopper 2 is moved from the material hopper 21 to the retracted position shown in FIG.
3 is supplied with a fixed amount of material resin, the material feeder 22
By the operation of the rodless cylinder device 30, the feeder hopper 23 moves forward to a position just above the cavity 12 a of the lower mold 12 and stops.

FIG. 3A shows the state of the shutter 23 after stopping.
a is released, and the material resin of the feeder hopper 23 is
It is thrown into the cavity 12a by dropping from the bottom opening and rises in a mountain shape, and the top of the shallow cavity protrudes from the parting surface. In such a supply state, when the movable platen 13 was lowered and the core 14a of the upper mold 14 was fitted into the cavity 12a to compress the material resin, the resin was applied around the lower mold 12 due to the surrounding dead space. The melting of the material resin by the heating means tends to cause unevenness in temperature, and defective products and burrs are likely to occur. Therefore, the material resin is leveled.

In FIG. 3B, the leveling is first stopped by re-advancing the material feeder 22 until the rear material leveling plate 27 reaches the far end of the cavity 12a. As a result, the lower edge of the material leveling plate 27 is pushed away so as to cut the top of the material resin, and the material is dropped to the dead pace.

FIG. 3C, the material feeder 22 after re-advancing.
To the rodless cylinder device 3 until the feeder hopper 23 is located at the drop port of the material hopper 21.
When 0 is moved back, the material leveling plate 26 on the front side scrapes off the remaining portion protruding from the parting surface in the process of moving backward and drops it into the dead space just before the cavity 12a.

As a result, the peak of the material resin in the cavity 12a is leveled down to the parting surface, and the material resin is relatively uniformly settled in the cavity 12a, and the dead space becomes small. Even with a material resin having a uniform melting and a high melt viscosity, the product 4 flows evenly in the cavity, and a product 4 having a good thickness distribution and a good molding state can be obtained, and burrs are reduced.

Further, in the material feeder 22 having the front material leveling plate 26 attached to the front end so that the lower edge is in contact with the parting surface of the lower mold 12, the mold 4 is opened together with the product 4 to form the upper mold 14 side. If the burrs 4a attached to the lower mold 12 fall onto the parting surface of the lower mold 12, the material leveling plate 26 pushes the burrs 4a out of the mold from the parting surface due to the forward movement during material feeding. It also serves as a member to be removed.

The drop of the burr onto the parting surface is as follows:
In most cases, this is caused by interference of a product take-out device (not shown) that enters and exits the upper mold 14 after the mold is opened. It rarely falls on the parting surface in front of the cavity 12a on the side. But,
The burrs are also thrown away by the material leveling plate 26 as the material feeder 22 advances, so that the burrs are removed from the mold without falling into the cavity 12a. For this reason, the burr removing device using air blow, which has been employed so far, becomes unnecessary, and the parting surface can be cleaned every time the material is supplied.

In the above embodiment, the material leveling plate 27 on the rear side is mounted slightly higher than the material leveling plate 26 on the front side, but is omitted in the drawing. 26 may be mounted slightly higher. In this case, the feeder hopper 23 moves forward to a position just above the cavity 12a and stops there. First leveling is performed from the material leveling plate 26 of FIG. Next, it is only necessary to re-advance to perform the secondary leveling by the material leveling plate 27 on the rear side. By this re-advancing, the burr can be removed by the material leveling plate 26 on the front side.

[Brief description of the drawings]

FIG. 1 is a side view of a compression molding machine provided with a material supply device according to the present invention.

FIG. 2 is a longitudinal sectional side view of the same material feeder.

FIG. 3 is an explanatory diagram showing supply of material resin and removal of burrs by a material feeder in order of process.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 mold clamping device 2 material supply device 3 machine base 4 product 12 lower die 12 a cavity 14 upper die 14 a core die 21 material hopper 22 material feeder 23 feeder hopper 25 shutter opening and closing device 26 front leveling plate 27 rear leveling Plate 30 Rodless cylinder 31 Slider

Claims (2)

[Claims] 1. A material hopper juxtaposed to a vertical mold clamping device having a mold at the top and bottom, a horizontally long material feeder provided below the material hopper so as to be able to advance and retreat with respect to the mold clamping device, and a material for the material hopper. A feeder hopper that is provided in the feeder and reciprocates between a dropping port of the material hopper and a cavity of the lower mold. A material supply device in a compression molding machine, characterized in that the material supply device is attached with a holding member. 2. The method according to claim 1, wherein the pair of material leveling plates are formed of an elastic material, and the front material leveling plate is attached to the tip of the material feeder at a height in contact with the parting surface of the lower mold. The material supply device in the compression molding machine according to claim 1, wherein