JPH042032Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a device for removing a screw head in a synthetic resin injection molding machine, compression molding machine, etc.

(Prior art) As shown in FIG. 3, a conventional injection molding device has a cylinder head 1 at the tip of a heating cylinder 1.
A is attached with bolt means 8, 8, and a screw head 3 is attached to the center of the heating cylinder 1 with a reverse screw 3.
A screw 2 connected via a is inserted rotatably or slidably in the axial direction. In the figure, 4 is a ring valve to prevent backflow.
5 is a wear plate. Screw head 3
To remove the cylinder head 1a from the screw 2 for replacement or cleaning, remove the cylinder head 1a from the heating cylinder, advance the screw 2 as far as it will go, and then secure the screw 2 in some way and adjust the screw head 3 accordingly. This is done by rotating it using a manual jig.

(Problem to be solved by the invention) In conventional devices, rotating the screw head 3 with a manual jig while fixing the screw 2 itself is difficult because the two are firmly connected by the wedge action of the screw. Therefore, it requires strength and skill to release it.

In the present invention, the screw head is fixed to the cylinder side and the screw is driven in reverse to separate the screw and the screw head.
A removable screw head removal device is provided.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides an annular cylinder having an axial guide means on the inner circumferential wall for removably attaching it to the tip of the heating cylinder from which the cylinder head has been removed. and an inner jig having engagement means for engaging with a notch formed on the outer periphery of the screw head in the inner circumferential wall, the inner jig being slidably attached to the guide means of the outer jig. It is composed of.

(Function) Since the present invention has the above configuration, the engaging means of the inner jig is engaged by using the notch formed on the outer periphery of the screw head for sending the molten resin to the cylinder head. This fixes the cylinder head to the heating cylinder side, and in this state, the screw between the screw and the screw head is tightened by rotating the screw in the opposite direction (generally, rotating clockwise when viewed from the molten resin supply side). Loosen the
The screw head can be removed.

(Example) Embodiments of the present invention will be described based on the drawings.

In describing the embodiment, the same reference numerals will be used for the same members as those of the conventional device described in FIG.

As shown in FIGS. 1 and 2, the device of the present invention consists of an inner jig 6 and an outer jig 7.

The outer jig 7 is a collar-shaped or annular body having a plurality of grooves (guide means) 7b extending in the axial direction on its inner circumferential wall 7a.

The inner jig 6 is a collar-shaped or annular body having a plurality of protrusions (guide means) 6a extending in the axial direction on its outer circumferential wall, and a plurality of protrusions (engaging means) 6b on its inner circumferential wall. be. Projection 6a of inner jig 6
is loosely fitted into the groove 7b of the outer jig 7. Of course, the relationship between the protrusions and the grooves may be reversed. The protrusions 6b of the inner jig 6 engage with notches 3a provided on the outer periphery of the screw head 3, which serve as flow paths for feeding the molten resin.

At the rear end of the screw head 3, there is a screw 2.
Since the screw means 3a is provided in the direction opposite to the normal rotation direction (generally the left rotation direction when viewed from the molten resin supply side) and is connected to the screw 2, the screw 2 can be advanced as far as possible to tighten the cylinder. The outer jig 7 is fixed to the heating cylinder 1 from which the head has been removed using bolt means 8, the protrusion 6d of the inner jig 6 is engaged with the notch 3a of the screw head 3, and the screw 2 is driven in reverse. , Screw head 3
The connection between the screw and the screw 2 can be easily released.

The rotation of the screw 2 is generally driven by a hydraulic motor, and by reversing the flow direction of the hydraulic oil, the screw 2 can be easily driven in reverse.

(Effects) Since the present invention has the above configuration,
It can be easily attached to the tip of the cylinder head using the fixing screw, and the screw can be driven in reverse with the screw head fixed, so even one worker can remove the screw head. This has the advantage that the work can be done quickly and easily without requiring any force or skill to turn the screw.

[Brief explanation of the drawing]

Fig. 1 is a vertical sectional view of the present invention in its implementation state, Fig. 2 is a left side view of Fig. 1, and Fig. 3 is a longitudinal sectional view of a conventional injection molding machine with a cylinder head installed. be. 1... Heating cylinder, 2... Screw, 3...
...Screw head, 6...Inner jig, 7...Outer jig.

Claims (1)

[Scope of utility model registration request] a substantially annular outer jig having an axial guide means on the inner circumferential wall for removably attaching the cylinder head to the tip of the heating cylinder from which the cylinder head has been removed; ,
1. A screw head removal device comprising an inner jig having an engaging means for engaging a notch formed on the outer periphery of the screw head in an inner circumferential wall.