JPS5852465B2 - Toggle type mold clamping device for die casting machines, etc. - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a toggle type mold clamping device for a die casting machine or the like.

More specifically, in a die casting machine or the like in which a toggle mechanism is interposed between a fixed platen and a movable platen, and a mold is opened and closed by a movable mold clamping cylinder, the fulcrum on the fixed platen side of the toggle link is connected to the mold clamping cylinder device. The cylinder device operates at a mold clamping force higher than the set mold clamping force, and the cylinder device is connected to an accumulation rake set at a predetermined pressure. This invention relates to a toggle type mold clamping device that can automatically absorb and adjust pressure by absorbing it into an accumulator.

In general, toggle-type mold clamping devices are convenient because they can easily speed up mold opening and closing movements, and are preferable for shortening cycle time and improving work efficiency. Fine adjustment of mold thickness is required.

That is, unless fine adjustments are made to changes in mold thickness caused by temperature changes in the mold, there is a risk of damage to the tie bars or tie bar nuts.

Therefore, conventionally, the dieper nut is adjusted each time by rotating the die-hide adjusting device or the like at the initial stage of the mold temperature and when the mold temperature is not constant.

In such conventional adjustment methods, the adjustment work is complicated and troublesome;
This requires a lot of time, which is unfavorable in terms of work efficiency.

The present inventor has devised the present invention in order to rationally and effectively solve the above-mentioned problems in adjusting for changes in mold thickness. In a die casting machine, etc., in which the mold is opened and closed via a toggle mechanism with a movable mold clamping cylinder device, the fulcrum of the toggle link supported on the fixed platen side is supported by the mold clamping cylinder device, and the cylinder device The object of the present invention is to provide a toggle type mold clamping device for a die casting machine or the like which operates at a mold clamping force higher than a set mold clamping force and is connected to an accumulator set at a predetermined pressure.

Therefore, in the present invention, when a pressure greater than a predetermined pressure is applied to the mold clamping cylinder device due to a change in mold thickness while clamping the mold at a predetermined pressure, the cylinder device is activated to release pressure to the accumulator to absorb the change in mold thickness. The mold clamping force is maintained at the predetermined mold clamping force, and also serves as an overload prevention device to absorb and adjust pressure increases, eliminating the troublesome and complicated adjustment work that was previously required. It has the advantage of being able to clean the area, improve work efficiency, and perform efficient casting.

Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

The drawing is an overall cutaway view of the main parts of a die casting machine having a mold clamping device according to the present invention, with columns 2...
is erected, and a lower mold (hard mold) 3 is placed between them.
A movable platen 4 is fitted and supported in the columns 2 so as to be movable up and down, and an upper mold (movable mold) 5 is supported on the lower surface of the platen 4.

A fixed platen 6 is fixedly supported at the upper end of the column 2... A toggle mechanism 7 is interposed between the fixed platen 6 and the movable platen 4 directly below this, and the lower fulcrum 8 of this mechanism is connected to the movable platen. The upper support point 9 is pivotally connected to the four corners of the lower surface of the fixed platen 6, and the links 10 and 4 are connected between the support points.
...is provided.

A mold clamping movable cylinder unit 11 is installed above the center of the fixed platen 6, and its rod 12 is connected to a part of the link 10 of the toggle mechanism T, and the cylinder unit 11 movably clamps the mold. The above is known.

In the above, the mold clamping cylinder units 13 are arranged at each of the four corners of the fixed platen 6, the pistons 15 are vertically inserted into the cylinders 14 installed vertically on the platen 6, and the brackets 16 are suspended below the pistons 15. A fulcrum 9 is pivotally mounted on this bracket 16, and a part of the link 103 of the toggle mechanism 7 is pivotally supported by the fulcrum 9.

Pressure oil is interposed between the upper surface of the piston 15 and the space 17 of the cylinder 14, and this pressure is maintained at the set mold clamping pressure, and when a pressure higher than this pressure acts on the unit 13 via the toggle mechanism, the piston 15 is activated.

In the illustrated example, four cylinder units are attached, and each unit bears the mold clamping pressure by dividing it into four equal parts.

The space 17 of each cylinder 14 described above is connected to each of the accumulators 18 disposed on the platen 6,
Each accumulator 18 is set to a predetermined pressure, and is set to absorb the pressure in the space 17 above this pressure.

Next, to explain its function and effect, the mold is clamped by the drive of the mold clamping movable cylinder unit 11 of the toggle mechanism 7, but the mold clamping pressure is transmitted to the movable platen 4 by the mold clamping cylinder unit 13 at the four corners. , perform mold clamping.

However, due to changes in mold temperature, the thickness of the mold changes at the initial stage and when the mold temperature is not constant, and increases as the mold temperature rises.

On the other hand, the mold is pressurized by the mold clamping cylinder unit 13, and an increase in the mold thickness is caused by an increase in pressure between the movable platen 4 and the toggle mechanism 7.
, the piston 1 of the cylinder unit 13 via the fulcrum 9
5, the pressure in the space 17 increases, and when this reaches a set value or higher, the balance with the accumulation rake 18 is lost and the pressure is absorbed by the accumulator 18.

When the mold thickness stops changing and becomes constant, the pressure also becomes constant, the pressure between the space 17 and the accumulator 18 is balanced, and the adjustment movement is stopped while the mold is clamped at the set pressure.

In this way, changes in mold thickness are automatically followed, absorbed and adjusted as changes in pressure.

The above mechanism not only absorbs changes in mold thickness, but also maintains the mold clamping force at a set pressure, and also serves as an overload protection device.

Since the accumulator is set at a predetermined pressure when the mold is opened, the pressure in the cylinder unit 13 decreases and returns to the unit 13 side for the next turn when the pressure is balanced.

Although the above embodiments were implemented on a die-casting machine, the application may be carried out freely, and the invention is not limited to the vertical type as shown in the drawings.

As is clear from the above, according to the present invention, changes in mold thickness caused by temperature changes can be automatically absorbed and adjusted, eliminating the need for troublesome and complicated work such as adjusting tie bar nuts in the past. It is possible to improve efficiency and production efficiency, and to prevent overload by maintaining the specified mold clamping force, it is also possible to install a cylinder unit or an accumulator at the fulcrum of the toggle mechanism. It has many advantages such as simple structure because it is only attached.

[Brief explanation of the drawing]

The drawing is an overall front view with main parts broken away, showing one embodiment of the present invention. In the drawing, 4 is a movable platen, 6 is a fixed platen, 7 is a toggle mechanism, 9 is a fulcrum, 11 is a mold clamping movable cylinder device, 1
3 is a mold clamping cylinder unit, and 18 is an accumulator.

Claims (1)

[Claims] 1. In a die casting machine, etc., in which a toggle mechanism is interposed between the fixed platen and the movable platen, and the mold is opened and closed via the toggle mechanism by a mold clamping movable cylinder device attached to the fixed platen, the fixed platen side of the toggle link The fulcrum is connected to a mold clamping cylinder device that operates at a mold clamping force or higher than a set mold clamping force, and the mold clamping cylinder device is set at a predetermined pressure, and absorbs the operation of the cylinder device that exceeds the pressure to prevent the mold from changing due to temperature changes. A toggle-type mold clamping device for a die-casting machine, etc., characterized in that it is connected to an accumulation rake that absorbs and adjusts thickness changes.