JPS6222347Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a molding machine such as a plastic molding machine, and particularly to a cover structure for covering a tie bar that guides a movable plate in the molding machine.

Plastic products (molded products) in various shapes
A plastic molding machine as shown in FIG. 1 is known as a machine for manufacturing plastic molding machines. This molding machine has a fixed plate (fixed platen) 2 vertically disposed at the center of the upper surface of a machine stand 1. As shown in FIG. 3, a fixed mold 3 is attached to one side of the fixed plate 2, and an extruder barrel 4 is connected to the other side.
The extruder barrel 4 is adapted to melt and inject the molding material contained in the material hopper 5 of the extruder barrel 4 into the fixed mold 3. In addition, the fixed mold 3
As shown in FIG. 2, a movable plate (movable platen) 7 to which a movable mold 6 is mounted is loosely fitted into a tie bar 8 vertically disposed on the fixed plate 2. Furthermore, the movable plate 7 is connected to a hydraulic cylinder 1 attached to a fixed plate 9 that supports the tip of the tie bar 8.
The movable mold 6 is fixed to the rod 11 of 0, moves forward as the rod 11 moves forward, and the movable mold 6 is clamped to the fixed mold 3. Further, as the rod 11 retreats, the movable mold 6 is separated from the fixed mold 3 and opened. A molding material is injected into the fixed/movable molds 3 and 6 during mold clamping, and after the molding material hardens, the mold is opened and the molded product 12 is taken out.

In this molding machine, a bush 13 is incorporated in the sliding portion of the tie bar 8 so that the movable plate 7 can move smoothly, and a sufficient amount of lubricating oil is applied or supplied to the tie bar 8. This prevents operational problems such as seizure.

By the way, since both the molds 3 and 6 are located inside the four tie bars 8, the tie bars 8 are exposed when the molds are open, and the molded product 12 easily comes into contact with the tie bars 8. For example, when the molded product 12 falls when the mold is opened, the molded product 12 occasionally comes into contact with the tie bars 8, and the lubricating oil adhering to the tie bars 8 adheres thereto. Therefore, there is a problem that the molded product gets dirty. Furthermore, even if the molded product 12 does not come into direct contact with the tie bar 8, the lubricating oil that adheres to the tie bar 8, which has become easily fluid due to the heat of sliding friction due to the strong impact when the mold is opened and closed, may drip and fall. Or the molded product 12 may be scattered.
It is undesirable because it may adhere to the surface.

Therefore, an object of the present invention is to provide a molding machine that does not stain molded products with lubricating oil.

In order to achieve such an object, the present invention provides a molding machine having a movable plate that is loosely fitted to a tie bar attached to a fixed plate and moves toward the fixed plate using the tie bar as a guide. One end of each is fixed, and a retractable cover is provided to cover the tie bar portion between a fixed plate to which a mold is attached and a movable plate to which a mold to be matched with the mold is attached, The present invention will be explained below with reference to Examples.

FIGS. 4a and 4b show a tie bar structure in a molding machine according to an embodiment of the present invention. In this embodiment, a telescopic bellows 14 made of a rubber material is inserted into each tie bar 8 fixed to a fixed plate (fixed platen) 2 so as to cover the tie bar 8. This bellows 1
Flanges 15 and 16 are provided at both ends of 4, and one flange 15 is fixed to a fixed plate (fixed platen) 2 to which a fixed mold is attached,
The other flange 16 is fixed to a movable plate (movable platen) 7 to which a movable mold is attached. By the movement of the movable plate 7, the bellows 14 contracts as shown in Figure a when the mold is closed, and expands as shown in Figure b when the mold is opened. The tie bar part located on the side is always bellows 14
covered by

According to this embodiment, the tie bar portion around the mold is covered by the bellows 14, and as a result, the lubricating oil adhering to the tie bar 8 may splash and adhere to the mold or the molded product, or the lubricant may adhere to the mold or the molded product. does not come into direct contact with the tie bar 8. Therefore, the molded product is not contaminated with lubricating oil.

Note that the present invention is not limited to the above embodiments. For example, a cover having the structure shown in FIGS. 5a and 5b and 6a and 6b may be used instead of the bellows.
This cover has a structure in which four sliding cylinders 17 each consisting of a truncated conical cylinder are stacked. The large diameter end of the first slide cylinder 18 having the smallest diameter of the slide cylinder 17 is bent outward to form a flange 19, and is fixed to the fixed plate 2 by this flange 19. Further, the small diameter end of the first slide cylinder 18 is also bent outward to form an outer stopper 20. Also, a second slide cylinder 21 is inserted into the outside of the first slide cylinder 18, a third slide cylinder 22 is fitted into the outside of the second slide cylinder 21, and a third slide cylinder 22 is fitted into the outside of the first slide cylinder 18.
The fourth slide cylinder 2 with the largest diameter is inserted into the outside of the
The large-diameter ends of No. 3 are bent inward to form inner stoppers 24, respectively. Also, the second
The small-diameter ends of the three-slide cylinders 21 and 22 are each bent outward to form an outer stopper 20. Further, the small diameter end of the fourth slide cylinder 23 is bent outward to form a flange 25. This flange 25 is fixed to the movable plate 7.
Then, when the mold is clamped, the first
~The fourth slide cylinder overlaps each other and covers the tie bar between the fixed plate 2 and the movable plate 7 while shrinking, and when the mold is opened, as shown in FIG.
~The fourth slide cylinder has an outer stopper 20 and an inner stopper 24 that are hooked to each other to form a single cylinder structure that covers the tie bar portion. As a result, the molded article is not contaminated by lubricating oil.

In addition, for covers with a sliding cylinder structure,
By cutting out along its axis, this cover can also be installed on existing plastic molding machines.

Furthermore, the present invention can be applied to machines and devices having sliding parts other than plastic molding machines, such as injection molding machines and blow molding machines.

As described above, according to the present invention, the tie bars to which lubricating oil adheres are not exposed on the path through which the molded product falls, so that manufactured products such as molded products are not contaminated with lubricating oil or the like.

[Brief explanation of the drawing]

Figure 1 is a front view of a conventional plastic molding machine.
Fig. 2 is a cross-sectional view showing the tie bar structure of the mold and movable plate, etc. Fig. 3 is a cross-sectional view of the mold attached to the fixed plate, and Fig. 4 a and b are one embodiment of the present invention. 5A and 5B are sectional views showing a tie bar structure according to another embodiment in each operating state, and FIGS. 6A and 6B are sectional views of the cover and FIG. 2... Fixed plate, 3... Fixed mold, 6... Movable mold, 7... Movable plate, 8... Tie bar, 12... Molded product, 14... Bellows, 17... Slide cylinder.

Claims (1)

[Claims for Utility Model Registration] (1) In a molding machine having a movable plate that is loosely fitted to a tie bar attached to a fixed plate and moves toward the fixed plate using the tie bar as a guide, one end of the fixed plate and the movable plate are respectively attached. What is claimed is: 1. A molding machine having a telescopic cover that covers a tie bar between a fixed plate to which a mold is attached and a movable plate to which a mold to be matched with the mold is attached. (2) The molding machine according to claim 1, wherein the cover has a bellows structure. (3) The molding machine according to claim 1, wherein the cover has a multilayered structure of a plurality of truncated conical cylinders and is slidably extendable and retractable.