JP3386388B2 - Molding machine equipped with multiple clamping cylinders and injection devices - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is intended for simultaneous molding of a plurality of molded products made of different resins, and is provided with two sets of molds, a plurality of mold clamping cylinders corresponding to the molds, and an injection device. The present invention relates to a machine, particularly a mold clamping mechanism.

[0002]

A fixed plate and a mold clamping cylinder installation plate, which are oppositely installed on the machine base by connecting four corners by a tie bar, and a movable plate which is inserted and supported by the tie bar, are formed in a rectangular shape. , A mold clamping device having a pair of left and right mold mounting surfaces on the surface facing the movable plate and one fixed plate, and a plurality of mold clamping cylinders and injection devices for each mold. In the injection molding machine having the above arrangement, since the fixed plate and the movable plate are rectangular, the span between the tie bars on one side is inevitably long and easily bent.

Further, since the two sets of dies are arranged separately on both sides of the mounting surface, the force points of the mold clamping force on the fixed plate and the movable plate are also two places on the left and right, and the stress due to the mold clamping force from both of them. Will be concentrated in the center of the fixed platen. Furthermore, since the tensile force acts on both sides supported by the tie bars on the fixed plate side, the rectangular fixed plate and movable plate are more easily bent than the square plate in terms of structure, and therefore movable with the fixed plate side. It becomes difficult to maintain the mold clamping parallelism (the parallelism of the mold closing surfaces of the pair of molds) of the molds separately mounted on the board side, and the following molding problems occur.

A deviation occurs in the mutual closing of the split molds, which causes burrs on the center side of the molds.・ Galling etc. occurs in a mold with a small draft taper.・ Pressing pins and other parts may break in precision molding dies.・ When a single molded product is molded with different molding materials by exchanging molds, if there is a difference in the mold clamping parallelism between the left and right molds, the primary molded product will fit into the replacement mold as designed. Otherwise, it becomes difficult to mold a good product.

A solution to such a problem is to form the fixed platen and the movable platen thick to make them difficult to bend. However, such a means causes an increase in the weight and size of the molding machine, resulting in processing. This is not preferable because it also increases the cost.

The present invention has been conceived in order to solve the above-mentioned conventional problems, and an object thereof is to adopt a power shaft without forming the fixed platen and the movable platen to be thicker than in the conventional case. It is an object of the present invention to provide a molding machine equipped with a plurality of new mold clamping cylinders and an injection device capable of maintaining the mold clamping parallelism by increasing the durability of the central portion of the stationary platen.

[0007]

SUMMARY OF THE INVENTION According to the present invention according to the above object, there are provided a fixed platen and a mold clamping cylinder installation plate, which are oppositely installed on a machine base by connecting four corners by a tie bar, and a movable plate inserted and supported by the tie bar. Is formed into a rectangular shape, and the opposing surfaces of the movable platen and the fixed platen are used as the mounting surfaces of the pair of left and right molds, and a plurality of mold clamping cylinders and an injection device are arranged for each mold. In, the fixed platen and the center part of the installation plate are connected by a power shaft having a required diameter, and the center part of the movable plate is inserted into the power shaft to maintain the mold clamping parallelism. is there.

Further, according to the present invention, the movable plate is provided with a rotary plate for exchanging molds on a surface facing the fixed plate, and the rotary plate is integrated with a hollow rotary shaft supported in the central portion of the movable plate, It also means that the power shaft is provided so as to extend through the rotation shaft and extend over the central portions of the fixed platen and the installation platen, and the power shaft is made of a tubular body that also serves as piping.

In such a structure, the power shaft serves as a supporting point at the center of the fixed platen and the movable platen, and the mold clamping force acting on the rectangular fixed platen and the movable platen is supported by the center part and both side parts. As in the past, even if the span of one side is long, it will be able to withstand the mold clamping force sufficiently and not bend. As a result,
Since the mold clamping parallelism is maintained, burrs and galling as in the past have been eliminated, the pressing pins in the mold for precision molding are prevented from being broken, and the mold clamping of the left and right molds is prevented. The inconvenience of fitting the primary molded product in the replacement mold due to the difference in parallelism is improved, and the non-defective molding of a single molded product of different materials can be easily performed by the mold replacement.

Further, although the molded product is apt to be limited to a thin product due to the occurrence of bending, it is possible to form a deep molded product by preventing the power shaft from generating the bending, and the number of molded products is increased. Even in such a case, the life of the mold is extended, the mold structure is relatively simple, and the wall thickness of the movable platen can be reduced depending on the mold clamping force.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the drawings, 1 is a fixed platen, 2 is a movable platen and 3 is a movable platen.
Is an installation board of the mold clamping cylinder 4, which is composed of a horizontally long rectangular board.

The fixed board 1 and the installation board 3 are connected to each other at their four corners by tie bars 5 and 5, and are installed opposite to each other on the machine base 6.
The movable plate 2 is inserted into and supported by the tie bars 5 and 5. The facing surface of the movable platen 2 and the fixed platen 1 is a mounting surface for the pair of left and right molds 7, 8, and one of them is a fixed mold 7a, 8a and the other is a movable mold 7b, 8b. 7 and 8 are attached to both boards.

The mold clamping cylinder 4 for the molds 7 and 8 and the injection device 9 are disposed on the installation board 3 and the machine base on the center line of the mold mounting surface. The mold clamping cylinder 4 is attached to the rear surface of the installation board 3, and its mold clamping ram 10 is connected to the movable board. The injection device 9 is mounted on the machine base.

Reference numeral 11 denotes a power shaft for maintaining the mold clamping parallelism of the mold. The power shaft 11 is provided so as to be connected to the central portions of the fixed plate 1 and the installation plate 3, and the central portion of the movable plate 2 is inserted into the power shaft 11. I am doing it. The diameter of the power shaft 11 is arbitrarily set depending on the plate thickness and the span of the fixed platen 1, but is preferably larger than the tie bar 5. Further, the power shaft 11 may be a tubular body, and in this case, the power shaft 11 is a movable die 7 on the movable platen 2 side.
It can also be used as piping for cooling water to b and 8b.

A clamp nut 12 is used to connect the power shaft 11, and the amount of bending of the fixed platen 1 is adjusted by the tightening degree of the power shaft 11 by the clamp nut 12, and the mold 7 attached at a predetermined position is used. 8 Adjust the proper mold parallelism to maintain a good condition at all times.

In FIGS. 3 and 4, a rotary plate 13 is provided on the surface of the movable plate 2 facing the fixed plate 1, and a pair of the molds 7 and 8 are attached to the left and right plate surfaces of the rotary plate 13 and the rear plate is provided. Gears 14, 1
By the reciprocating rotation (180 °) of the rotary plate 13 by 5, the fixed molds 7a and 8a and the movable molds 7b and 8b are alternately exchanged to form a single molded product of different molding materials. It shows a case of a different material injection molding machine.

The rotary plate 13 is integrally connected to a hollow rotary shaft 16 supported in the central portion of the rectangular movable plate 2, and the power shaft 11 penetrates the rotary shaft 16 to form a rectangular shape. The fixed platen 1 and the installation platen 3 are provided over the central portion thereof. A clearance is provided between the power shaft 11 and the rotary shaft 16 and
Is reciprocally rotated together with the rotary plate 13 regardless of the power shaft 11 to exchange the mold.

Therefore, even in a mold clamping device in which the movable platen 2 formed in a rectangular shape together with the fixed platen 1 is provided with the rotary plate 13 for mold replacement, the mold is clamped by the power shaft 11 provided at the center. The bending due to the force is prevented, and the mold clamping parallelism is maintained. As a result, the inconvenience caused by the difference in the mold clamping parallelism between the left and right molds 7 and 8 is improved, and the mold clamping parallelism is maintained when molding two-color molded products, waterproof connectors, bottle caps, etc. by replacing the molds. It is also easy to mold non-defective products made of different materials that are strongly required.

[Brief description of drawings]

FIG. 1 is a plan view of a molding machine including a plurality of mold clamping cylinders and an injection device according to the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a plan view of a mold exchange type molding machine including a plurality of mold clamping cylinders and an injection device according to the present invention.

4 is a sectional view taken along line BB of FIG.

[Explanation of symbols]

1 Fixed board 2 movable plate 3 installation boards 4 mold clamping cylinder 5 tie bars 6 machines 7,8 mold 9 injection device 10 Mold clamping ram 11 power shaft 12 Clamp nut 13 rotating plate 14 and 15 gears 16 rotation axes

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Claims (3)

(57) [Claims] 1. A fixed board and a mold clamping cylinder installation board, which are connected to each other on the machine base by connecting four corners by tie bars, and a movable board inserted and supported by the tie bar, are formed in a rectangular shape. An injection molding machine in which a surface facing a fixed plate is a mounting surface for a pair of left and right molds, and a plurality of mold clamping cylinders and an injection device are arranged for each mold, the center of the fixed plate and the installation plate. A plurality of mold clamping cylinders and an injection device, characterized in that the parts are connected by a power shaft having a required diameter, and the center part of the movable plate is inserted through the power shaft to maintain the mold clamping parallelism. A molding machine equipped with. 2. The movable plate is provided with a rotary plate for mold replacement on a surface facing the fixed plate, and the rotary plate is integrated with a hollow rotary shaft supported in the central portion of the movable plate to rotate the rotary plate. 2. A molding machine comprising a plurality of mold clamping cylinders and an injection device according to claim 1, wherein the power shaft is provided so as to extend through a shaft and extend over the central portions of a fixed platen and an installation platen. 3. The molding machine having a plurality of mold clamping cylinders and an injection device according to claim 1, wherein the power shaft is made of a tubular body which also serves as a pipe.