JPH06352B2 - Rotary injection molding machine - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a rotary injection molding machine capable of intermittently circulating and moving a plurality of metals to perform injection molding of rubber, synthetic resin or the like. Is.

[Prior Art] A conventional molding machine of this type has a machine base 1 as shown in FIG.
A pressure receiving plate 2 is provided above the base plate by being supported by a tie bar 3 and a support column 4 at the center of the machine base, and a rotating plate
6 are provided in parallel, and the upper mold holding plate 8 and the lower mold clamping plate 9 are vertically movably inserted into a plurality of tie bars 7, 7 provided over the upper and lower rotating plates 5, 6 to clamp the mold. Make up the unit.

An opening / closing rod 10 is provided below the mold clamping plate 9, and a cam follower 12 that moves in contact with a track rail 11 on the machine base is provided on a side portion of the opening / closing rod 10, and the upper rotating plate 5 and the mold holding plate are provided. 8, a spring 13 for holding the mold closed is provided so that the mold 14 is not opened during the rotational movement.

In such a rotary molding machine, after the mold is clamped through the open / close rod 10 by the mold clamping cylinder 15 provided in the machine base, injection is performed from the side of the mold. Further, the mold opening is performed by the hook 16a at the tip of the piston of the mold opening cylinder 16 in the machine base.
Then, the cam follower 12 is locked.

[Problems to be Solved by the Invention] In the above-described conventional technique, the cam follower 12 receives the force of the spring 13 and rolls on the track rail 11. Therefore, the service life of the cam follower 12 and the track rail 11 is short, and the mold is closed for long-term use. The retention is impaired, and burrs are likely to occur.

Further, since the position of the cam follower 12 is displaced from the center of the mold clamping, an eccentric load is applied to the mold clamping plate, the tie bar bush is worn quickly, the mold closing accuracy is impaired, and a product with high molding accuracy cannot be obtained. .

Furthermore, since the mold clamping unit is configured by using the upper and lower turntables, it is difficult to perform maintenance, and in some cases, the turntables may have to be disassembled.

The present invention has been conceived in order to solve the above-described conventional problems, and an object thereof is to perform mold closing and holding by using a cam follower, and mold closing and holding by spring pressure can be surely performed. It is to provide a rotary injection molding machine that can be easily maintained.

[Means for Solving the Problem] A feature of the present invention according to the above-mentioned object is to provide a mold clamping fixing plate in which a mold clamping cylinder is provided above a mold clamping position of a pressure receiving plate on a machine base.
It is supported and provided by a tie bar and a column in the center of the pressure receiving plate, and a rotary table is supported and supported by bearings on the pressure receiving plate, and a lower fixing plate and an upper fixing plate are integrally formed by a tie bar at a predetermined position of the rotating table. Install multiple mold clamping units vertically with the lower fixed plate attached.
The mold clamping unit includes a mold clamping plate having a pressure receiving rod and a central opening / closing rod located immediately below the ram of the mold clamping cylinder, and a plurality of spring members interposed below the mold clamping plate so that the mold clamping unit is movable. A die mounting plate connected to the tie bar is provided so as to be vertically movable, and a shutter plate of a pressure receiving rod is slidably provided under the upper fixed plate.

[Operation] In the above configuration, the mold clamping unit rotates together with the rotary table by a predetermined angle. At the mold clamping position, the clamping plate is pressed through the mold opening / closing rod by the operation of the mold clamping cylinder, and the mold is clamped.

The mold clamping force after injection molding is the spring member between the mold clamping plate and the mold mounting plate until the shutter plate that restrains the pressure receiving rod and receives the reaction force of the spring member is removed from the top end of the pressure receiving rod. It is held moderately by the resilience of.

[Embodiment] Hereinafter, a rotary injection molding machine of the present invention will be described with reference to Figs.
This will be described in detail with reference to the embodiment shown in the figure.

In the figure, reference numeral 21 denotes a pressure receiving plate provided on the stepped portion of the machine base 22. Above the mold clamping position of the pressure receiving plate 21, a mold clamping fixing plate 24 in which a mold clamping cylinder 23 is installed is provided. It is provided so as to be supported by the column 26 of the.

On the pressure receiving plate 21, a donut-shaped rotary table 28 integrally having a large-diameter annular gear 27 on the back side is fitted and supported by a bearing 24 fixed on the pressure receiving plate to rotate. It is provided freely.

An annular gear 27 of the rotary table 28 meshes with a gear 30 of a motor 29 for intermittent rotation mounted on the pressure receiving plate 21,
The motor 29 causes the rotary table 28 to rotate in one direction while repeatedly stopping at 90 ° intervals.

31 is a mold clamping unit which includes a lower fixing plate 32 and an upper fixing plate 3.
3 are integrally connected by tie bars 34 at respective corners, and the tie bars 34 are overlapped with a mold clamping plate 35 and a plurality of spring members 36 below the mold clamping plate, as shown in FIG. , An opening / closing rod 39 which is vertically movably inserted through a mold mounting plate 38 movably connected by pins 37, and which penetrates through the upper fixing plate 33 at the center and both sides of the upper part of the mold clamping plate 35. And a pressure receiving rod 40, and the shutter plate 41 of the pressure receiving rod 40 is attached to the upper fixing plate 3
3 has a structure in which a guide plate 42 is provided on the lower side and slidably provided.

The mold clamping unit 31 is vertically installed by fixing the lower fixing plates 32 to the four sides on the rotary table 28, and the upper fixing plate 33 is rotatably attached to the column 26. A member 44 is connected to the fitted retaining ring 43 with each other.

Reference numeral 45 denotes a mold opening / closing cylinder, which is attached downward to a frame 46 provided above the mold clamping unit stop position adjacent to the mold clamping position. At the lower end of the piston of the mold opening / closing cylinder 45, a member 47 into which the neck 39a of the upper end of the opening / closing rod is laterally introduced and fitted is provided with a guide rod 48.

Reference numeral 49 denotes an opening cylinder of the shutter plate 41, which is horizontally attached to the support column 26, and an engaging element 50 with the rear end of the shutter plate is attached to the tip of the piston.

Reference numeral 51 is a mold, which is a lower fixing plate 32 of the mold clamping unit 31.
And the die mounting plate 38. Further, although omitted in the drawing, in the mold 51, the side portion of the upper mold is formed in a recess together with the mold clamping plate 35 and the mold mounting plate 38, and the nozzle portion of the injection cylinder 52 is provided in the recess from the side. After inserting as shown in the figure, the piston 54 of the cylinder 53 on the nozzle portion is abutted against the receiving member 55 of the upper fixing plate 33, and the nozzle is touched by its reaction force.

In the above structure, each mold clamping unit 31 rotates 90 ° together with the rotary table 28. At the mold clamping position, the ram 23a of the mold clamping cylinder 23 presses the mold clamping plate 35 via the mold opening / closing rod 39 to clamp the mold 51.

After the injection is completed, when the injection cylinder 52 retracts and separates from the mold 51, the ram 23a rises to the original position for rotation,
Although the pressing force is removed, the mold clamping force of the mold 51 is reduced by the spring member 36.
It is held moderately by the elastic force of. This elastic force is maintained until the mold clamping unit 31 reaches the mold opening / closing position, and the shutter plate 41 that restrains the pressure receiving rod 40 and receives the reaction force of the spring member 36 is opened by the opening cylinder 49 at the mold opening / closing position. The pressure receiving rod 40 is removed from the top end of the pressure receiving rod.
Is released when is free.

After that, the open / close rod 39 is moved by the mold open / close cylinder 45,
The mold 51 is pulled up as shown and the mold 51 is opened. After the molded product is taken out, the mold is closed by the opening / closing cylinder 45, and the shutter plate 41 is pushed in by the opening cylinder 49, so that the pressure receiving rod 40 is restrained again. Then, the mold clamping unit 31 in the mold opening position is transferred to the mold clamping position by the rotary table 28.

Therefore, in molding rubber or the like, strong mold clamping is required only during injection molding, and a small mold clamping force is sufficient during vulcanization and curing, so that the time until the mold is opened can be appropriately maintained by the spring pressure.

[Effects of the Invention] As described above, according to the present invention, the mold clamping fixing plate 24 in which the mold clamping cylinder 23 is provided above the mold clamping position of the pressure receiving plate 21 on the machine base.
Is supported by a tie bar and a column 26 at the center of the pressure receiving plate, and a rotary table 28 is supported by bearings on the pressure receiving plate, and a lower fixing plate 32 and an upper fixing plate are provided at predetermined positions on the rotating table 28. 33 and a plurality of mold clamping units 31 integrally connected by a tie bar 34,
Since the lower fixing plate 32 is fixedly installed vertically and clamped vertically from above, the mold clamping force is received by the entire lower fixing plate, and the pressure on the mold clamping unit is equalized. Therefore, unlike the conventional case, an eccentric load does not occur during mold clamping.

Further, a mold clamping plate 35 having a pressure receiving rod 40 and a central opening / closing rod 39 located immediately below the ram of the mold clamping cylinder 23 installed in the upper part, and a plurality of spring members 36 interposed below the mold clamping plate 35 are movable. The die mounting plate 38 connected to the tie bar 34
The shutter plate 41 of the pressure receiving rod 40 is slidably provided on the lower side of the upper fixed plate 33 so as to form the mold clamping unit 31, and mold clamping other than during injection molding is performed.
Since it is done by the spring member between the mold clamping plate and the mold mounting plate, the interval of the spring member can be set arbitrarily according to the mold, and even when the vulcanization and curing time is long in the molding of rubber, etc. The mold can be held in good balance by pressure and with an appropriate force.

Furthermore, since the mold clamping unit is only installed on the rotary table, the mold opening interval can be set sufficiently, so the mold is not limited to one with a constant mold thickness as before, and maintenance is also possible. It has features such as easy operation.

[Brief description of drawings]

1 to 4 show an embodiment of a rotary injection molding machine according to the present invention. FIG. 1 is a side view of the I-I line developed in FIG. 2, FIG. 2 is a plan view, and FIG. Figure is a plan view of the shirt plate, Figure 4 is a vertical cross-sectional view of the mold clamping plate and mold mounting plate,
FIG. 5 is a schematic vertical sectional side view of a conventional rotary injection molding machine. 21 ……… Pressure receiving board 22 ………… Machine stand 23 ………… Clamping cylinder 24 ………… Clamping fixed board 25 ………… Tie bar 26 ………… Supporter 27 ………… Annulus gear 28 ………… Rotary table 29 Motor for intermittent rotation 31 Mold clamping unit 32 Lower fixing plate 33 Upper fixing plate 34 Tie bar 35 Mold clamping plate 36 Spring member 38 ... Mold mounting plate 39 ... Opening / closing rod 40 ... ... Pressure receiving rod 41 ... Shirt plate 51 ... Mold

Claims (1)

[Claims] 1. A mold clamping fixed plate having a mold clamping cylinder therein is provided above the mold clamping position of the pressure receiving plate on the machine base while being supported by a tie bar and a column at the center of the pressure receiving plate, and on the pressure receiving plate. A rotary table is supported by bearings, and a plurality of mold clamping units, in which a lower fixing plate and an upper fixing plate are integrally connected by tie bars, are attached at predetermined locations on the rotating table. Installed, the mold clamping unit,
A mold clamping plate in which a pressure receiving rod and a central opening / closing rod located immediately below the ram of the mold clamping cylinder are placed in the upper part, and a mold mounting plate movably connected to the lower side of which a plurality of spring members are interposed. A rotary injection molding machine characterized in that the shutter plate of the pressure receiving rod is slidably provided on the lower side of the upper fixed plate by being inserted through a tie bar so as to be vertically movable.