JPH0732025Y2 - Mold clamping device in injection molding machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a mold clamping device provided in an injection molding machine.

[Conventional technology]

Conventionally, as a mold clamping device of an injection molding machine, those shown in FIGS. 8 and 9 are known.

That is, the mold clamping device shown in FIG. 8 is called a direct pressure type, and the movable plate 4 slidably provided on the tie bar 3 connecting the fixed plate 1 and the end plate 2 to the mold provided on the end plate 2. It is configured to be moved directly along the tie bar 3 by the tightening cylinder 5, and the moving side mold 6 attached to the moving plate 4 is pressed against the fixed side mold 7 attached to the fixed plate 1 to clamp the mold.

The mold clamping device shown in FIG. 9 is of a toggle type, and is configured to move the moving plate 4 by a mold clamping cylinder 5 provided on the end plate 2 via a toggle mechanism 8 to perform mold clamping. ing.

Separately from the above, the fixed plate is provided with a mold clamping cylinder that moves the tie bar, and an opening / closing cylinder that moves the moving plate along the tie bar. After closing the mold, a mold clamping device has been proposed in which the tie bar is fastened to the piston rod of the mold clamping cylinder with a lock member, and the movable plate is moved together with the tie bar by the mold clamping cylinder to clamp the mold (Japanese Patent Laid-Open No. 2000-242242). 63-42827).

[Problems to be solved by the device]

Both of the conventional mold clamping devices shown in FIGS. 8 and 9 are
Since the mold clamping cylinder 5 largely projects to the outside of the end plate 2, a wide installation space is required. Especially when using an injection molding machine in a clean room as represented by disk molding, a clean space is required. However, there is a problem in that it cannot be used effectively.

Further, the above-mentioned tie bar lock system requires a lock member for fastening the tie bar to the piston rod of the die clamping cylinder at the time of mold clamping, and moreover, the lock member operates to fasten the tie bar to the piston rod, and There is a problem that it takes time to release the fastening.

It is an object of the present invention to provide a mold clamping device which is compact and does not take up space, does not waste time opening and closing a mold, and is particularly suitable for an injection molding machine used in a clean room.

[Means for Solving the Problems]

In order to achieve the above object, the present invention provides a plurality of tie bars having a piston at one end and a feed screw at the other end, a moving plate including a fixed plate having a fixed side mold and a movable side mold. The piston is inserted into a mold clamping cylinder formed on one of the first plates of the plates, and the feed screw is screwed into a feed nut provided on the outer surface of the other second plate, and the first screw is inserted. A transmission member that is installed between the plate and the second plate and that synchronizes the rotations of the plurality of feed nuts with each other is provided on the outer surface of the second plate provided with the feed nut. The protective plate, which is attached to the outer side surface by a bolt via a space regulating member, is provided so as to be sandwiched together with the plurality of feed nuts. The rotary drive for rotating the respective feed nut through the provided was a structure provided with airtight means over said tie bars of the inner surface and the portions on the outer surface of the protection plate of the second plate.

[Action]

To perform mold clamping, first, the rotary drive device is operated to rotate the feed nut. As a result, the moving plate moves toward the fixed plate to bring the moving side mold into contact with the fixed side mold.

Then, the mold clamping cylinder is operated to strongly press the moving side mold against the fixed side mold to clamp the mold.

Further, in order to open the moving side mold away from the fixed side mold, the mold clamping cylinder and the rotation driving device are moved in the opposite direction to move the moving plate in the direction away from the fixed plate.

In the mold clamping device of the present invention, a mold opening / closing mechanism mainly composed of a rotary driving device and a feed nut, and a mold clamping cylinder for finally clamping the mold are separately incorporated into a fixed plate and a movable plate. Therefore, it can be compactly assembled when it is manufactured, so that it does not take up a lot of space and does not require a large installation space.

Further, the protect plate sandwiching the feed nut and the transmission member between the second plates has a supporting function of the rotation drive device, and has a cover airtight function of the feed nut and the transmission member.
It is rational because it can add the bearing function of the feed nut.

〔Example〕

1 to 7 show an embodiment of the mold clamping device according to the present invention, in which the reference numeral 11 is a fixed plate. This fixing plate 11 is fixed to a base 12 with bolts 13, fixed-side molds 14 are attached to the center of the fixing plate 11, and the opposite sides of the shaft holes 15 (Fig. 6) are attached to the cylinder cover 16 at the four corners. A mold clamping cylinder 17 closed by is provided. The cylinder cover 16 is fixed to the fixing plate 11 with a plurality of bolts 18 (only one is shown in FIG. 6 and the like).
And a seal member 19 is fitted in the shaft hole 15.

Further, reference numeral 21 is a tie bar, which has a piston 22 at one end and a feed screw 23 at the other end, and the piston 22 is inserted into the mold clamping cylinder 17 to fix the fixing plate 11.
The shaft hole 15 is movably inserted in the axial direction while the free rotation in the circumferential direction is stopped by an appropriate means. A pair of working fluid flow holes 24, 25 are formed in the fixed plate 11 so as to open in the left and right cylinder chambers A, B of the piston 22, and a working fluid is passed through one side by a pump (not shown). Through the hole 24, as shown by the arrow in FIG.
6, the tie bar 21 moves to the right in FIG. 6, and when the working fluid is sent from the other flow hole 25 into the cylinder chamber B as shown in FIG. 7, the tie bar 21 moves to the left in FIG. It is configured to move.

A moving plate 28 having a feed nut 26 (Fig. 4 etc.) and a slide bush 27 is inserted into the tie bar 21, and the feed screw 23 of the tie bar 21 is inserted into the slide bush 27, and the feed nut 23 is attached to the feed screw 23. Are attached by screwing through a large number of balls 29. And moving plate 28
A movable mold 30 is attached to the fixed mold 14 so as to face the fixed mold 14. The feed nut 26, ring gear (transmission member) 31, and drive gear 32 are movable plates.
28 and the protect plate 36 which is attached to the moving plate 28 via a distance collar 34 (FIG. 5) via a distance collar 34 (FIG. 5), and is provided so as to be separated from the moving plate 28. It has been blocked.

The ring gear 31 meshes with each feed nut 26 and rotates them in synchronization with each other.
It is bearing on both 28 and protect plate 36.
The drive gear 32 is attached to a rotary shaft 37 of a rotary drive device 33 with a key 38 and meshed with a ring gear 31.

The rotation drive device 33 rotates the feed nut 26 via the ring gear 31 and the drive gear 32, and is composed of an electric motor, a hydraulic motor, and the like that can rotate in the forward and reverse directions.
Is supported on the outer surface (the surface opposite to the moving plate 28).

Therefore, in the above configuration, when the rotation drive device 33 is operated, the feed nut 26 rotates with respect to the feed screw 23, and the moving plate 28 moves along the tie bar 21. Although the moving plate 28 is configured to move on the base 12 by the rollers 41, it may be configured to simply slide.

Then, reference numeral 39 is a bellows (airtight means), one end of which is fixed to the moving plate 28 and the other end of which is fixed to the tie bar 21 to hermetically seal between them. 40 is a protect plate
An airtight tube (airtight means) attached to 36, which airtightly covers the protruding portion of the tie bar 21.

Next, the operation of the mold clamping device in the injection molding machine according to the present invention configured as described above will be described.

FIG. 1 shows the mold open state in which the movable side mold 30 is separated from the fixed side mold 14, and in order to clamp the mold from this state, the rotary drive device 33 is operated to rotate the feed nut 26. , Move the moving plate 28 to the right in FIG.
The movable mold 30 is brought into contact with the fixed mold 14 of the fixed plate 11 by approaching the fixed mold 11. When the fixed side mold 14 and the moving side mold 30 are combined in this way, as shown in FIG. 6, the working fluid is press-fitted into the cylinder chamber A of the mold clamping cylinder 17 from the flow hole 24 and the tie bar 21 is moved to the right. Then, the moving plate 28 together with the tie bar 21 is moved toward the fixed plate 11 and the mold is clamped. During the mold clamping movement of the moving plate 28, the bellows 39 contracts and the free end of the tie bar 21 projects from the moving plate 28, but since the bellows 39 and the airtight tube 40 keep the part airtight, dust is generated. It does not leak and pollute the working room.

Further, in order to open the mold from the mold clamped state, the working fluid is sent into the cylinder chamber B from the circulation hole 25 to move the tie bar 21 to the seventh position.
While moving to the left in the figure, the rotation driving device 33 is operated in the opposite direction to reversely rotate the feed nut 26, and the moving plate 28 is moved away from the fixed plate 11.
In this case, the tie bar 21 is pulled out from the slide bush 27 of the moving plate 28 to the fixed plate 11 side, but the bellows
As 39 stretches out and maintains airtightness, dust is prevented from leaking out as in mold clamping.

In addition, the mold clamping device of the embodiment shown in the figure does not have the end plate as in the conventional case, and the feed screw of the tie bar 21 is not provided.
The end on the 23 side is in a free state, but if necessary, the end plate 42 can be provided as shown by the dashed line in FIG. In this case, if the rotation driving device 33 comes into contact with the end plate 42 to prevent the size reduction, a hole is formed in the end plate 42 to avoid the contact of the rotation driving device 33. Further, although the feed screw 23 and the feed nut 26 in the drawing have a ball screw structure, the feed screw 23 may be directly screwed into the feed nut 26 without using the ball 29.

Furthermore, in the mold clamping device shown in the figure, a mold clamping cylinder 17 is provided on the fixed plate 11 and a feed nut is provided on the moving plate 28 side.
26 and rotary drive 33 are provided, but fixed plate
The feed nut 26 and the rotation driving device 33 may be provided on the 11 side, and the mold clamping cylinder 17 may be provided on the moving plate 28. Ring gear 31 is omitted, drive gear 32 is fed nut
It is also possible to carry out by directly engaging with 26.

[Effect of device]

As described above, in the mold clamping device of the injection molding machine of the present invention, the plurality of tie bars having the piston at one end and the feed screw formed at the other end includes the fixed plate having the fixed side mold and the movable side metal mold. The piston is inserted into the mold clamping cylinder formed on one of the first plates of the moving plate provided with the mold, and the feed screw is screwed into the feed nut provided on the outer surface of the other second plate. And is installed between the first plate and the second plate,
A transmission member for synchronizing the rotations of the plurality of feed nuts with each other is provided on an outer surface of the second plate provided with the feed nut, and a bolt is provided between the second plate and the outer surface of the second plate via a space regulating member. The protective plate is attached between the plurality of feed nuts, and the protect plate is provided with a rotary drive device that rotates each feed nut via the transmission member. An airtight means is provided on the inner surface of the second plate and the outer surface of the protect plate so as to cover the tie bars of those portions, and a mold opening / closing mechanism mainly composed of a rotation drive device and a feed nut. And, the mold clamping cylinder that finally clamps the mold is divided into a fixed plate and a moving plate and built in them, so the whole can be compactly assembled. It is possible. Further, the protect plate, which sandwiches the feed nut and the transmission member between the second plates, has a function of supporting the rotary drive device, and has a cover airtight function of the feed nut and the transmission member and a bearing function of the feed nut. Therefore, it is rational, and it is easier to simplify the structure to make it compact.
Further, unlike the conventional mold clamping device in which the tie bar is fastened to and released from the piston rod of the mold clamping cylinder by the lock member, no wasted time is required for opening and closing the mold.
Therefore, when a large installation space is unnecessary and the disk is exclusively manufactured in a clean room, the valuable clean space can be effectively used.

[Brief description of drawings]

1 to 7 show an embodiment of the present invention.
1 is a front view of the entire mold clamping device, FIG. 2 is a side view, FIG. 3 is a sectional view taken along line (III-III) of FIG. 1, and FIG. 4 is (IV) of FIG. -IV) line sectional view, FIG. 5 is a sectional view of the same (VV) line portion, and FIGS. 6 and 7 are sectional views showing the operation of the mold clamping cylinder. FIG. 8 is a partially broken front view of a conventional direct pressure type mold clamping device, and FIG. 9 is a partially broken front view of a conventional toggle type mold clamping device. 11 ... Fixed plate, 14 ... Fixed side mold, 17 ... Mold clamping cylinder, 21 ... Tie bar, 22 ... Piston, 23 ... Feed screw, 26 ...
Feed nut, 28 ... moving plate, 30 ... moving side mold, 33 ...
Rotary drive.

Claims (1)

[Scope of utility model registration request] 1. A plurality of tie bars (21) having a piston (22) at one end and a feed screw (23) at the other end.
Is a mold clamp formed on the first plate (11) of either the fixed plate (11) having the fixed mold (14) or the moving plate (28) having the movable mold (30). The piston (22) is inserted into the cylinder (17), and the feed screw (23) is screwed into the feed nut (26) provided on the outer surface of the other second plate (28) to attach the first screw to the first plate. The plurality of feed nuts (26) are rotated on the outer surface of the second plate (28) which is installed between the plate (11) and the second plate (28) and provided with the feed nut (26). A protective plate (36) in which a transmission member (31) for synchronizing with each other is attached to the second plate (28) and an outer surface of the second plate (28) by a bolt (35) via a gap regulating member (34). It is sandwiched between the feed nuts (26) and The rate (36) is provided with a rotation driving device (33) for rotating each feed nut via the transmission member (31), and the rotation driving device (33) is provided between the inner surface of the second plate (28) and the protect plate (36). A mold clamping device in an injection molding machine, characterized in that airtight means (39, 40) is provided on the outer surface of the tie bar (21) in those portions.