JPH0129063Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a safety device in a mold clamping device of an injection molding machine.

[Prior Art] As is well known, an injection molding machine is provided with a fixed plate and a movable plate each having a mold attached thereto, which are arranged opposite to each other via tie rods, and the movable plate has a space between the fixed plate and the clamp cylinder. The movable platen is configured to be able to move forward and backward via a connecting tie rod, and when the movable platen is moved by a drive cylinder and approaches the fixed platen, the molds attached to the respective plates are fitted and clamped. After that, resin is injected at high pressure by the injection mechanism to fill the cavity in the mold, and after being cooled for a certain period of time in the mold clamping state, the mold clamping state is released and the respective molds are separated. The molded product is taken out.

In this case, while the molds for the movable platen and fixed platen are fitted and clamped, the safety gate is closed to shield the movable platen and fixed platen from both sides. As a safety device for the safety gate that is used in the injection molding machine, a method is adopted in which a part of the hydraulic circuit applied to the main body of the injection molding machine is installed in the interlock circuit, and a method is adopted in which the interlock is electrically incorporated into the sequence circuit. .

However, with the above-mentioned safety device, there is a high possibility that the interlock circuit may be closed due to some disturbance or equipment failure, and reliability is insufficient in terms of safety.

In response, mechanical safety devices have been proposed that place emphasis on safety.

For example, a movable platen is provided with a stopping rod, and a fixed platen is provided with a guide block with a hole passing through the stopping rod, so that mold clamping operation is possible only when the safety door of the injection molding machine is closed. There is a safety device that is constructed such that when the safety door is open, a baffle plate closes the hole and prevents movement of the stop rod, in other words, movement of the movable platen.

[Problems to be solved by the invention] However, in the safety device using the above-mentioned stopping rod, it is necessary to adjust the position of the stopping rod in response to changes in the clamp stroke due to changes in the mold, etc. In some cases, if the main body of an injection molding machine becomes large, the operating points will inevitably be in a high place.
There were problems such as dangerous work.

This invention does not have the above-mentioned deficiencies, and not only fully demonstrates its function as a safety device, but also has a mechanical safety structure that can be applied even if the clamp stroke of the injection molding machine itself is changed. The purpose is to provide equipment.

[Means for Solving the Problems] In order to achieve the above object, the safety device in the mold clamping device of the injection molding machine of the present invention includes two or more tie rods connecting the fixed platen and the clamp cylinder, and a fixed An injection machine equipped with a movable platen guided by tie rods placed opposite the platen, a mold that can be opened and closed on each of the fixed platen and movable platen, and a hydraulic mechanism that allows the movable platen to move forward and backward relative to the fixed platen. In the safety device of the mold clamping device of a molding machine, a safety rod having multiple locking grooves is fixedly installed on the side between the clamp cylinder and the fixed platen, and the safety rod is hooked into and removed from the locking grooves of the safety rod on the movable platen. It has a fixed and flexible latching mechanism.

[Function] A safety rod with multiple latching grooves has a latching mechanism fixed to the movable platen that can be freely engaged and removed in any of the latching grooves in response to changes in the clamp stroke due to changes in molds, etc. It latches and works to mechanically prevent the movable platen.

[Example] Hereinafter, the present invention will be described in detail based on the illustrated example.

Figure 1 is a front view of the device of the present invention attached to the main body of an injection molding machine, Figure 2 is a plan view of the same, Figure 3 is a front view showing the safety rod and the latching mechanism, and Figure 4 is the latching mechanism. FIG. 3 is a system diagram showing a drive system of the mechanism.

The overall structure will be explained with reference to FIGS. 1 and 2, but since the specific structure of the injection molding machine body is a well-known structure, its explanation will be omitted.

1 and 2, a support frame 21 for supporting the stationary platen 1 is installed on the base frame 20 of the injection molding machine main body, a mold 1a is attached to the support frame 21, and then The injection part mechanism 30 inside the injection molding machine main body is provided at the injection molding machine body.

On the other hand, tie rods 23, 23 are provided in parallel arrangement on the fixed platen support frame 21, and the movable platen 3 is provided on these tie rods 23, 23 so as to be movable forward and backward by a hydraulic mechanism (not shown).

Reference numeral 4 denotes a mold attached to the movable platen 3, which faces the mold 1a of the fixed platen 1, so that the molds 1a and 4 are brought into close contact with each other by moving the movable plate back and forth. We are making it compatible. Note that 6 is a limit switch that detects the closed state of the safety door 40.

Reference numeral 10 denotes a safety rod having a plurality of step-shaped locking grooves 9 carved on its upper surface, and includes a safety block 5 attached to the upper part of the fixed platen 1 and the movable platen 3.
The clamp cylinder 7 is fixed to the upper side between the clamp cylinder 7 and the stationary plate 1 via a support 8 provided at the upper end of the clamp cylinder 7 attached to the clamp cylinder 7 .

Reference numeral 11 denotes a locking mechanism attached to a holding plate 12 provided on the upper part of the movable platen 4, and as shown in an enlarged view in FIG. A holding block 11b having a holding block 11a is fixed to the holding block 12 on the movable platen 3, and a cylinder 11c for air or the like is provided on the upper part of the holding block 11b. 11e, a compression coil spring 11 is attached to the piston rod 11d.
f is attached, and the locking piece 11e is pressed against the locking groove 9.

Port terminals 11g and 11h connected to the control circuit of the drive system shown in FIG. 4 are attached to the outside of the cylinder 11c.

Note that the locking groove 9 carved on the upper surface of the safety rod 10 forms a stepped groove inclined in one direction, and the locking piece 11e of the locking mechanism is locked in the locking groove 9. It is designed so that it does not come off when it is closed.

To explain the operation of the latch mechanism using the drive system diagram shown in Fig. 4, air is supplied from an air supply source A via a manual switching valve B, is purified by a filter C, is once depressurized by a pressure reducing valve P, and then a solenoid valve Port 11h provided on the outside of cylinder 11C of the locking mechanism by switching with E
Alternatively, the port 11g is configured as a closed circuit.

In addition, S is a silencer, which is a muffler used when exhausting air from the solenoid valve E.

When using a safety device, as shown in FIG. 4, when the mold clamping is completed and the safety door 40 is opened, the solenoid valve E is energized to supply air from the air supply source A to the port 11g. The piston rod 11d in the locking mechanism is lowered, and the locking piece 11e at the tip is secured to the safety rod 10.
It is latched into the latching groove 9 to be in a fixed state.

On the other hand, when the injection molding machine is clamped,
The solenoid valve E is demagnetized and operated to open the cylinder 11c.
The internal pressure source is discharged from the port 11h, the piston rod 11d of the latching mechanism is raised, and the latching piece 11e latched to the latching groove 9 of the safety rod 10 is removed to release the latching state. do.

The latching groove is not limited to a stepped groove, and the latching mechanism is not limited to a latching piece, but may be a latching groove or a latching mechanism of other structure.

[Effects of the invention] As described above, in the present invention, a safety rod having a plurality of latching grooves is fixed on the side between a clamp cylinder and a fixed platen, and the safety rod is latched to the latching grooves of the safety rod on the movable platen. A removable latching mechanism is fixedly installed on the movable platen, and the removable latching mechanism fixed to the movable platen can be latched to either of the latching grooves in response to changes in the clamp stroke due to changes in the mold, etc. Since the movable platen is mechanically blocked, there is no need to make adjustments even if the clamp stroke is changed due to changes in molds, etc., and is not only easy to manufacture and assemble, but also has safety features. However, it has very good advantages of sufficient reliability.

[Brief explanation of the drawing]

Fig. 1 is a front view showing the main body of an injection molding machine equipped with the device of the present invention, Fig. 2 is a plan view showing the main body of the injection molding machine equipped with the device of the present invention, and Fig. 3 is a safety rod and latching. FIG. 4, an enlarged front view showing the mechanism, is a system diagram showing the drive system of the latching mechanism. 1...Fixed plate, 3...Movable plate, 1a, 4...Mold, 7...Clamp cylinder, 9...Latching groove, 1
0... Safety rod, 11... Latching mechanism, 23...
Tyrotsud.

Claims (1)

[Scope of claim for utility model registration] Two or more tie rods connecting a fixed platen and a clamp cylinder, a movable platen facing the fixed platen and guided by the tie rods, and an opening/closing device attached to each of the fixed platen and movable platen. In the safety device of the mold clamping device of an injection molding machine that is equipped with a flexible mold and a hydraulic mechanism that allows the movable platen to move forward and backward relative to the fixed platen, multiple hooks are installed on the sides between the clamp cylinder and the fixed platen. A safety device in a mold clamping device for an injection molding machine, characterized in that a safety rod having a stop groove is fixedly installed, and a locking mechanism that can be freely hooked and detached from the locking groove of the safety rod is fixed to a movable platen. .