JPH0462248B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical field to which the invention pertains] The present invention relates to a method for controlling the mold clamping speed of a mold clamping cylinder using a link mechanism.

[Prior art and its problems]

In general, in link-type mold clamping devices, increasing the moving speed of the mold clamping cylinder increases the impact and noise of the mold, shortening the life of not only the mold but also the mold clamping device. It is necessary to reduce the moving speed of the tightening cylinder. From this point of view, in the past, a limit switch was used to set the switching position of the moving speed of the mold clamping cylinder, and the position detection signal of this limit switch was used to switch the hydraulic control valve to reduce the moving speed of the mold clamping cylinder. The method of doing so was adopted. However, with this conventional method, it takes a lot of time to repeat trial and error to set the limit switch at the optimal position, and since the speed changes in two stages, smooth deceleration cannot be achieved and shocks can occur. There were some difficulties, such as not being able to sufficiently alleviate the situation.

[Purpose of the invention]

The purpose of the present invention is to omit the limit switch conventionally used for detecting the position of the mold clamping cylinder, and to output a non-contact and appropriate mold clamping cylinder speed switching signal to smoothly control the mold clamping cylinder speed. An object of the present invention is to provide a mold clamping speed control method for a link type mold clamping device.

[Key points of the invention]

A mold clamping speed control method of a link type mold clamping device according to the present invention is a mold clamping speed control method of a link type mold clamping device configured such that a mold clamping cylinder performs a mold clamping operation on a movable die with respect to a fixed die via a link mechanism. In the control method, a load meter is provided between the fixed die and the tie bar, and when a predetermined load output signal generated by the load meter reaches a predetermined value during the mold clamping operation of the movable die, a signal is sent to the mold clamping speed control actuator. The present invention is characterized in that it is configured to issue a command to reduce the speed of the mold clamping cylinder.

In the mold clamping speed control method of the link type mold clamping device, it is preferable that the load meter is configured to detect the elongation applied between the tie bar and the fixed die as an electrical displacement after the movable die contacts the fixed die. It is.

In addition, the load output signal of the load meter and the set value signal that sets the load signal suitable for switching the speed of the mold clamping cylinder are input to the comparator, and when these signals match, the high speed mold clamping speed command is It is preferable to configure it so that a predetermined constant mold clamping speed command is output.

[Embodiments of the invention]

Next, an embodiment of a mold clamping speed control method for a link type mold clamping device according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic diagram of a link type mold clamping device that implements the mold clamping speed control method of the present invention. That is, in FIG. 1, reference numeral 10 indicates a fixed frame, and a fixed die 1 is mounted on this fixed frame 10.
2. The movable die 14 and the link housing 16 are arranged to face each other along the axis of the tie bar 18. Note that a link mechanism 20 is provided between the movable die 14 and the link housing 16, and this link mechanism 20 advances the movable die 14 relative to the fixed die 12 under the action of a mold clamping cylinder 22 to achieve the required mold clamping. configured to do the following.

However, in the present invention, the tie bar 1
A load meter 24 for detecting mold clamping force is provided on the fixed die side of No. 8. This load meter 24 is
For example, a conventionally known device configured as shown in FIGS. 2 and 3 may be employed. That is, a shaft hole 26 is bored at the center of the fixed die 12 of the tie bar 18 from the outer end thereof, and the differential secondary winding is placed on both sides of the primary winding 28 in the center on the inner circumference of the shaft hole 26. 3
0 and 32 are arranged in parallel in the axial direction, and furthermore, the opening end of the shaft hole 26 is appropriately closed and fixed with a holding lid 34, and each of the windings 28, 32 is arranged in the shaft hole 26.
30 and 32, one end of which is elastically held by a spring 36, and an iron core 38 that is displaceable in the axial direction in response to expansion and contraction of the tie bar 18 is housed. When the movable die 14 is tightened with respect to the fixed die 12 and stress is generated in the tie bar 18, the load meter 24 configured in this way is used to control the distance between the fixed die 12 side and the tie bar 18 side based on this. elongation occurs, and the iron core 38 moves and displaces in accordance with this elongation, which generates a differential output in the output circuit between the secondary windings 30 and 32, which is appropriately controlled by an external indicator via a conductor wire to indicate stress. Measurement display can be performed.

However, the load meter 24 indicates that when the movable die 14 is clamped by the mold clamping cylinder 22 via the link mechanism 20, the movable die 14 moves forward and the taping line (the movable die 14 and the fixed die 12 contact each other). position), a predetermined load output is generated. In this way, since the movable die 14 is moved by the link mechanism 20, the mold clamping cylinder 2
2 has a sufficient distance to decelerate after reaching the taping line until reaching the mold clamping limit. Therefore, in the present invention, as shown in FIG. It is compared with the load setting value, and when these signals and the setting value match, a predetermined output signal is generated from the comparator 42, and this output signal is used as a mold clamping speed switching signal to the mold clamping speed control actuator 46 of the mold clamping device. and configured to provide speed control.

In the present invention, based on the control system shown in FIG. 4, the operation of the comparator 42 and the operation of the mold clamping speed control actuator 46 are configured to implement a mold clamping processing routine as shown in the flowchart of FIG. do. That is, when the required load output for detecting that the movable die 14 has reached the parting line is obtained from the load meter 24, and when it matches the value set by the setting device 44, the comparator 42 outputs a predetermined reliability signal. If this is obtained, the actuator 46 is controlled to switch from the high speed mold clamping command to the constant speed mold clamping command or the deceleration mold clamping command. In such mold clamping speed control, the load output signal and mold clamping speed signal are transmitted to the mold clamping cylinder 2.
If shown in relation to the stroke of No. 2, the characteristics shown in FIG. 6 can be obtained.

〔Effect of the invention〕

As is clear from the above embodiment, in the parting line where the movable die contacts the fixed die, a load meter installed between the fixed die and the tie bar detects the required load output signal, and the movement is performed based on this signal. By controlling the speed of the link mechanism that moves the die in a predetermined manner until the die reaches its clamping limit, it is possible to not only achieve smooth mold clamping control without contact, but also to reduce the generation of shock and noise, and to improve the performance of the equipment. It has many excellent advantages such as being able to significantly improve the overall lifespan.

The preferred embodiments of the present invention have been described above, but for example, load meters etc. are not limited to this embodiment, and can detect the load output generated between the movable die and the fixed die during mold clamping. It goes without saying that any other structure may be used as long as it is configured as such, and that various other design changes may be made without departing from the spirit of the present invention.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a link-type mold clamping device that implements the mold clamping speed control method according to the present invention, FIG. 2 is a sectional view showing the configuration and arrangement of the load meter shown in FIG. 1, and FIG. The electrical system diagram of the load meter shown in the figure,
FIG. 4 is a control system diagram showing an embodiment of the mold clamping speed control method according to the present invention, FIG. 5 is a flowchart diagram of the mold clamping speed control method according to the present invention, and FIG. 6 is a mold clamping speed control method according to the present invention. FIG. 3 is a characteristic diagram showing the relationship between a mold clamping load output signal from a load meter and a mold clamping speed signal in a speed control method. 10...Fixed frame, 12...Fixed die, 1
4...Moving die, 16...Link housing, 1
8... Tie bar, 20... Link mechanism, 22...
Mold clamping cylinder, 24...Load meter, 26...
Shaft hole, 28...Primary winding, 30, 32...Differential secondary winding, 34...Press cover, 36...Spring,
38... Iron core.

Claims (1)

[Claims] 1. A mold clamping speed control method of a link type mold clamping device configured to perform a mold clamping operation on a movable die with respect to a fixed die via a link mechanism by a mold clamping cylinder, in which A load meter is provided in between, and when a predetermined load output signal generated by this load meter reaches a predetermined value during the mold clamping operation of the movable die, a command is given to the mold clamping speed control actuator to reduce the speed of the mold clamping cylinder. A mold clamping speed control method for a link type mold clamping device, characterized in that it is configured as follows. 2. In the method for controlling the mold clamping speed of a link type mold clamping device according to claim 1, the load meter converts the elongation between the tie bar and the fixed die into electrical displacement after the movable die contacts the fixed die. A mold clamping speed control method for a link type mold clamping device configured to detect as follows. 3. In the mold clamping speed control method of a link type mold clamping device according to claim 1, a set value that sets a load signal suitable for switching between the load output signal of the load meter and the speed of the mold clamping cylinder. A mold clamping speed control method for a link type mold clamping device, comprising inputting signals to a comparator and outputting a predetermined low speed mold clamping speed command from a high speed mold clamping speed command when these signals match.