JPH02141206A - Mold clamping apparatus - Google Patents

Abstract

PURPOSE:To facilitate maintenance, and enable the weight of guide rods to be reduced around 60%, and also make an installation space therefor to be small by arranging guide rods, being accommodated symmetrically in holding a piston rod so as to be parallel to the axis of the piston rod, in the vicinity of both ends of a link housing. CONSTITUTION:A cross head 7 is fixed to the top of the piston rod 9 of a mold clamping provided on the outer end surface of the approximately central part of a link housing 1. Furthermore, guide rods 10 for guiding the cross head 7 smoothly and freely coming in and out are arranged in a manner such that they are accommodated symmetrically within the link housing 1 in holding the piston rod 9. And, both ends of the guide rods 10 are fixed by being accommodated with the link housing 1 after they passed through the through holes of the cross head 7, and they conduct smoothly coming in and out movement of a movable disc 3 passed through the column via a telescopic movement of a toggle mechanism 6.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a tuple toggle type mold clamping device used in an injection molding machine or the like.

[Prior Art] Fig. 4 is a vertical cross-sectional view showing a conventionally known mold clamping device, in which the half above the center line shows the state before mold closing starts, and the half below the center line shows the state when mold closing is completed. Indicates the status of each.

The mold clamping device in FIG. 4 includes a link housing 1, a fixed platen 2. Movable plate 3. Mold 4. bed 5. Toggle mechanism6. Crosshead 7. The mold clamping cylinder consists of an 8° piston rod 9 and a guide rod 10.

In the double toggle mold clamping device of an injection molding machine, as shown in FIG. A mold clamping cylinder 8 is attached to the mold clamping cylinder 8, the tip of the piston rod 9 of the cylinder 8 is attached to the cross head 7, and the rod 7 is moved forward and backward along the guide rod 10 inserted into the cross so as to be freely movable forward and backward. The toggle mechanism 6 is actuated via the rod 7, and the movable a3 is inserted into a column (not shown) with respect to the fixed platen 2, and then the mold is attached so as to be swingable back and forth to open and close the mold.

It is designed to perform a mold clamping operation.

[Problem that Hatsu 1 Town is trying to solve] However, the piston rod 8 is located on the side opposite to the fixed plate 2 of the movable a3.
One end of the mold is fixed, and the other end is inserted through the insertion hole of the crosshead 7 and the link housing l so that it can move forward and backward, so that the movable platen 3 can be moved from the bent backward position of the mold opening of the toggle mechanism to the mold clamping position. Therefore, the long guide rod 10 is safe, especially in the mold opening state where the toggle mechanism is bent as shown in FIG. will protrude symmetrically across the piston rod 9, so
Installation of the injection molding machine requires a large space, and it is difficult to connect the extrusion pin between the link housing 1 and the movable Ci 3 and to maintain the lubricating piping for the toggle mechanism 6.

The present invention was made in order to solve the problems of the conventional double toggle type mold clamping device.
The aim is to significantly shorten the overall length of the

[Means to solve the problem] In the present invention, in order to eliminate the above-mentioned drawbacks.

In a double toggle type mold clamping device, two sets of toggle mechanisms are provided between the movable platen and the link housing, and the movable platen is moved forward relative to the fixed platen by the operation of the toggle mechanism to perform the mold clamping operation. A guide rod is inserted into the insertion hole of a crosshead that is fixed perpendicularly to the piston rod, and is housed near both ends in the link housing, so that the axis of the guide rod and the axis of the piston rod are parallel to each other. The guide rods were arranged symmetrically with the piston rod in between.

In the above configuration, the guide rods are housed symmetrically with the piston rod in between so as to be parallel to the axis of the piston rod near both ends of the link housing. When pressure oil is supplied to the rear chamber or front chamber of the tightening cylinder, the toggle mechanism is expanded and contracted as the piston rod moves back and forth, thereby performing mold clamping and mold opening. By housing the guide rod in the link housing, a pair of kite rods are arranged with the piston rod in between, and the kite rods are shortened. This creates a space where maintenance is easy. Also.

The weight of the kite rod is reduced by about 60% compared to the conventional model, which has great advantages in terms of cost.
Since the guide rod does not protrude to the rear of the link housing even under the closed condition, the installation space for the mold clamping device can be small.

[Example] Example 1 Figure 1 shows a link housing in which a guide rod is housed symmetrically with a piston rod in between, and the end of a third toggle link is placed at an eccentric position of the second toggle link. This is an overall view of the rotatably connected mold clamping device with a partial cross-section of the side.
The upper half of the center line in Figure 1 is the mold opening position, and the first
The lower half of the figure represents the mold closing position.

Embodiment 1 of the present invention will be described using Figure 5f.

The symbol 1 is a link housing, 2 is a fixed plate, and 3 is a movable plate. The link housing 1 and the stationary platen 3 are installed on the bed 5 with a predetermined spacing between them.

6 is a j-glue mechanism, and is a first toggle link 6a.

Consisting of a second toggle link 6b and a third toggle link 6C, the end of the third toggle link 6C is rotatably connected to the eccentric position of the second toggle link 6b, and the third
The first toggle link 6a and the second toggle link 6C
An unpaired toggle mechanism is formed by connecting the toggle links 6b to each other with a toggle pin so that they can be bent. One end of the second toggle link 6b is pivotally connected to the surface of the link housing 1 facing the movable platen 3, and the end of the other first toggle link 6a is pivoted to the surface of the movable platen 3 facing the link housing 1. The second toggle link 6b
The piston rod 9 of the mold clamping cylinder 8 is connected to the cross rod 7 through the third toggle link 6C, and the cross rod 7 is provided on the outer end surface of the approximately central portion of the link housing l. It sticks to the tip of the. Further, a guide rod 10 that guides the rod 7 smoothly forward and backward to the cross, which is one of the connecting members for making the toggle mechanism 6 extend and retract, is housed symmetrically in the link housing l with the piston rod 9 in between. After passing both ends of the guide rod 10 through the insertion holes of the rod 7, the guide rod 10 is housed and fixed in the link housing 1, and is connected to a column (not shown) through the slow expansion and contraction movement of the toggle mechanism 6. Movable plate 3 inserted into
It is designed to move forward and backward smoothly. Note that the center portions of both side surfaces of the link housing l are provided with protrusions for fixing the guide rods 10 at both ends. The piston rod 9 is located in the rear chamber 8a of the mold clamping cylinder 8.
When the toggle link 6a is pressurized in the forward direction by supplying pressure oil to the toggle link 6a.

6b is pressed, and on the other hand, when pressed in the backward direction, it exhibits the action of pulling back. Symbols 4a and 4b are molds,
They are respectively attached to opposing surfaces of the fixed platen 2 and the movable platen 3.

Next, the mold opening/closing and mold clamping operations will be explained.

In the mold open state shown in the upper half of the center line in Figure 1,
When pressure oil is supplied to the rear chamber 8a of the mold clamping cylinder 8, the piston rod 9 moves forward and is stretched to the cross via the third toggle link 6C rotatably connected to the rad 7.
Furthermore, the stretching force is applied to the tip of the third toggle link 6C.
It is transmitted to the second toggle link 6b and the first toggle link 6a via a toggle pin located approximately in the central region B of the second toggle link 6b. Further, since the movable platen 3 pivotally connected to the first toggle link 6a is in a free state, the first toggle link 6a is pushed and extended by the rotational force of the second toggle link 6b, and the movable platen 3 starts moving forward. . moreover,
As shown in the lower half of the center line of FIG. 1, the third toggle link 6C, the first toggle link 6a, and the second toggle link 6b extend straight, and the movable platen 3 is connected to the mold 4a,
4b is closed and the mold is in a clamped state. In this state, the cavities in the molds 4a and 4b are injected and filled with molten metal or molten resin, and then pressure holding and cooling steps are performed. next,
Under such a mold clamping condition, the front chamber 8 of the mold clamping cylinder 8
When pressure oil is supplied to b and the piston rod 9 is moved slightly backward, the rad 7 moves straight back to the cross attached to the tip of the piston rod 9, and the third toggle link rotatably connected to the cross hend door. As 6C bends and retreats, both the first toggle link 6a and the second toggle link 6b bend and retreat, making them movable! R3 also moves straight backwards and mold opening begins there.

Further, as the piston rod 9 moves backward significantly, the second toggle link 6b is pulled by the third toggle link 6C and rotates inward. As a result, the third toggle link 6C bends inward from the connecting portion of the first toggle link 6a and the second toggle link 6b using the connecting portion on the movable platen 3 side as a fulcrum and shortens, and the movable platen 3 also retreats accordingly. Eventually, the mold opens until the mold opens, resulting in the state shown half way from the center line in FIG. In this way, one mold clamping cylinder 8 can continuously perform mold opening or mold clamping.

As a result 1, as in Embodiment 1 of the present invention, the guide rod 1
0 is housed in the link housing 1, it becomes very easy to connect the push-out pin (not shown) and maintain the lubricating piping of the toggle mechanism. Furthermore, even in the mold open state as shown in the upper half of the center line in FIG. 1, the guide rod 10 is housed in the link housing l and does not protrude rearward from the link housing l, so that it does not interfere with the mold clamping device. Donations will improve and safety will be maintained. Also,
Since the guide rod 10 is shortened, the weight is reduced by about 60% compared to the conventional example shown in FIG. 4, resulting in a significant cost reduction.

Embodiment 2 In Fig. 2, guide rods are arranged symmetrically with the piston rod in between in the link housing l, and the end of the third toggle link is placed approximately in the central area of the second toggle link. This is an overall partially sectional side view of the rotatably connected mold clamping device, with the upper half of the center line in Figure 2 showing the mold opening position, and the half below the center line in Figure 2 showing the mold closing position. Representing each.

Embodiment 2 of the present invention will be explained with reference to FIG.

Similar to Embodiment 1, the link housing 1 has a protrusion at the center of both sides and both ends of the guide rod 10 are fixed, and a third toggle link 6 is attached as the link mechanism 6 to this.
Rotatably attach the toggle pin to any position B (hereinafter referred to as approximately the center) from the end of C and the center of the long sleeve of the second toggle link 6b to the protrusion in one direction on the mounting side of the third toggle link 6C on the short axis. Because it is a combination of connected things.

The toggle mechanism 6 shortened to the bent state at the start of mold closing is
The movement stroke when operating in the extension direction to move the nf moving platen to mold closing, and conversely, the movement stroke when operating the toggle mechanism 6 from the extended state at the start of mold opening to move the iii moving platen 3 to mold opening. Compared with the conventional example shown in FIG. 4, the movement stroke is xo longer than the distance required for opening and closing the mold. Furthermore, the connection of push-out pins (not shown) and the maintenance of the simple piping of the toggle mechanism 6 are made very easy.

Furthermore, even when the mold is opened half way from the center line in FIG. 2, the guide rod 10 is housed in the link housing 1 and does not protrude to the rear of the link housing 1. Donations will be made easier and safety will be maintained. Furthermore, since the guide rod IO is shortened, the weight is reduced by about 60% compared to the conventional example shown in FIG. 4, resulting in a significant cost reduction. Furthermore, by rotatably connecting the end portion of the third toggle link 6C to the substantially central region B of the second toggle link 6b of the toggle mechanism 6, the following effects can be considered. This will be explained in a standard JIY manner while comparing FIGS. 2 and 4.

In FIG. 2, approximately central area B of the second toggle link 6b
The movement stroke when the crosshead 7 is moved from the mold opening limit position to the mold clamping position with the state IE rotatably connected to the end of the third toggle link 6C is defined as Ll. on the other hand,
As shown in FIG. 4, using the same device, the end of the third toggle link 6C is rotatably connected to the eccentric position A of the second toggle link 6b, and the a-shead 7 is moved to the mold opening position. The movement stroke when moving from position to mold clamping position is Ll
.

Then, L is 40.7Lbi, and the movement stroke of the crosshead 7 in FIG. 2 of the present invention is about 30% shorter than that of the conventional example shown in FIG.

Therefore, along with this, the piston row and do, which are installed at right angles to the crosshen door, are also about 30% shorter than in the conventional example, and the mold clamping cylinder 8 that houses the piston rod is also about 30% shorter than in the conventional example. It will be short and good. However, when the end of the third toggle link 6C is rotatably connected to the approximately center area B of the second total link 6b as shown in FIG. 2, the mold clamping force in the mold clamping cylinder 8 is reduced. If the supply of pressure oil to the mold clamping cylinder 8 is the same as in the conventional example, as a result, the inner diameter of the mold clamping cylinder 8 and the outer diameter of the piston rod 9 will be approximately 41 mm compared to the conventional example. % or more, the movement stroke of the movable platen 3 is the same in the present invention and the conventional example as LQ=LQ' in FIGS. 2 and 4, but
Since the mold clamping cylinder stroke of the present invention is about 30% shorter than that of the conventional example, the oil, y, +, supplied to the mold clamping cylinder 8 can be reduced by about 0%, and therefore the mold opening/closing time is reduced by about 0%. becomes 1υ. Furthermore, the length from the outer end of the mold clamping cylinder 8 to the end of the mold attachment of the movable platen is L2, respectively, as shown in FIGS. 2 and 4.

If L2' is L2-0.85L2°, the device of the present invention shown in FIG. 2 is approximately 15% shorter than the conventional example shown in FIG. This means that the space may be small.

[Effects of the Invention] As is clear from the above embodiments 1 and 2, the third toggle link is located at an arbitrary position in one direction on the third toggle link mounting side of the short axis from the long sleeve center of the second toggle link of the toggle mechanism. The toggle link is rotatably connected with a toggle pin, and the guide rod is fixed and stored after passing through the crosshead insertion hole in the link housing symmetrically with the piston rod in between, so the weight of the guide rod is the same as that of the conventional model. Approximately 6
0% reduction, the guide rod does not protrude from the link housing even when the mold is open, increasing safety, and creating a space where people can easily enter and exit between the cross and the rad and the movable platen when the mold is closed. This makes maintenance easier. Also, the length of the crosshead movement stroke is approximately 3
Since the mold can be shortened by 0%, the product cycle is increased, and since the mold clamping cylinder is shorter, the overall length of the mold clamping device is also shortened by approximately 15%, allowing for efficient installation in a narrow space.

[Brief explanation of the drawing]

1 and 2 are longitudinal cross-sectional views showing different embodiments of the present invention, FIG. 3 is a vertical cross-sectional view from m to ■ of FIG.
The figure shows a longitudinal sectional view of a conventional example similar to the present invention. In Figures 1.2.4, the two halves of each figure show the mold open state, and the lower half shows the mold-clamping fly. l...Link housing, 2...Fixed plate. 3...Movable plate, 4...Mold, 5...
Bed, 6... Tokuru mechanism. 7...Crosshead, 8...Mold clamping cylinder,
9...Piston rod, IO...Kite rod. Patent applicant: Ube Industries, Ltd.

Claims (1)

[Claims] In a double toggle type mold clamping device, two sets of toggle mechanisms are provided between the movable platen and the link housing, and the movable platen is moved forward relative to the fixed platen by the operation of the toggle mechanism to perform the mold clamping operation. The guide rod, which is inserted into the insertion hole of the cruise head fixed perpendicularly to the piston rod so that it can move forward and backward, is housed near both ends of the link housing, so that the axis of the guide rod and the axis of the piston rod are parallel to each other. A mold clamping device characterized in that guide rods are arranged symmetrically with a piston rod in between.