JP2629118B2 - Mold thickness adjustment device for hollow molding machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold thickness adjusting device for a hollow molding machine, and more particularly to an apparatus for variably adjusting a mold thickness adjustment for a mold by an elastic member provided in a toggle mechanism. Regarding new improvements.

[0002]

2. Description of the Related Art Conventionally, a mold thickness adjusting device of this kind of a hollow molding machine is generally known as shown in FIGS.
Has been adopted. That is, what is indicated by reference numeral 1 in FIGS. 3 and 4 is a mold that can be opened and closed and includes a first mold part 2 and a second mold part 3.
In the cavity 1a, a parison 6 hanging from a crosshead 5 of the extruder 4 is supplied.

The second mold part 3 is connected to a toggle mechanism 9 having a pair of bendable first and second toggle pieces 7 and 8 via a first mold holder 10. A guide block 12 for holding a shaft support 11 to which the toggle pieces 7 and 8 are flexibly connected includes a pair of center positioning guide bars 1.
It is configured to be guided by 3,14.

The guide block 12 is configured to be able to reciprocate in the axial direction by a feed screw 16 such as a ball screw which is rotated by an electric motor 15.
Is provided with a second mold holder 17.

A pair of rods 19, 20 are connected to a rear plate 18 connected to the second toggle piece 8, and each rod 19, 20 is a first connector connected to the second mold holder 17. 21, the second mold part 3 is connected to the first toggle piece 7 via the first clevis 7a, and the second toggle piece 8 is connected to the rear plate via the second clevis 8a. 18. Accordingly, the toggle mechanism 9 is constituted by the above-described toggle pieces 7 and 8, the clevises 7a and 8a, and the rear plate 18.

Accordingly, in the above-described configuration, the electric motor 1
5 is operated to move the guide block 12 with the feed screw 16, so that the toggle pieces 7, 8 become linear or bent along the positions indicated by the dotted and solid lines as shown in FIG. In the case, the mold parts 2 and 3 move in the closing direction via the rods 19 and 20 to be closed, and in the case of a bent shape, the mold parts 2 and 3
3 move in the direction to open each other and open. Further, when the mold 1 is replaced with another mold having a different thickness, the first mold is replaced with the first mold.
Insert the first spacer S ₁ of required thickness between the first clevis 7a and the second die holder 10 of the toggle piece 7, further
The second clevis 8a of the second toggle piece 8 and the rear plate 18
The second spacer S ₂ having a required thickness was inserted between the mold and the mold 1 to adjust the mold clamping force.

[0007]

The mold thickness adjusting device of the conventional hollow molding machine has been configured as described above.
The following issues existed. In other words, since a very large force is output immediately before each toggle piece is fully extended, the amount of movement before the fully extended piece is small, and a large change in the compression force of the mold due to a slight dimensional difference when the mold is replaced. In order to avoid the problem, the thickness dimension of the mold has to be corrected by inserting a spacer having a different thickness every time the mold is replaced. Since the work of attaching and detaching the spacer must be performed in accordance with the thickness dimension of the mold, it takes a long time, and the necessary holding force is often not obtained due to poor adjustment. Further, it was not possible to easily cope with a difference in thickness of a mold having a variation of a certain dimension or more (large dimensional difference).

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and in particular, the thickness of the mold relative to the mold is variably adjusted by an elastic body connected to a toggle mechanism. An object of the present invention is to provide a mold thickness adjusting device for a hollow molding machine.

[0009]

SUMMARY OF THE INVENTION According to the present invention, there is provided a mold thickness adjusting device for a hollow molding machine, wherein a mold is opened and closed and a mold thickness is adjusted via a toggle mechanism which expands and contracts by an electric motor. In a mold thickness adjusting device of a molding machine, a mold thickness adjusting portion including a gap formed between a rear plate of the toggle mechanism and a second clevis, and an elasticity provided between the rear plate and the second clevis. And a fastening unit for fastening the rear plate and the second clevis via the elastic body.

[0010] More specifically, the elastic body is held by a clevis recess formed in the second clevis and a rear plate recess formed in the rear plate.

[0011] More specifically, the elastic body is constituted by a disc spring.

More specifically, a guide pin provided on the second clevis is inserted into a guide hole of a guide member provided on the rear plate, and when the second clevis and the rear plate move, positioning guides are provided. Is performed by the guide pin and the guide member.

[0013]

In the mold thickness adjusting device for a hollow molding machine according to the present invention, the gap formed between the second clevis and the rear plate by the elastic body provided between the second clevis of the toggle mechanism and the rear plate. By variably adjusting the mold thickness adjustment amount consisting of the fastening means, the mold thickness adjustment amount is freely adjusted according to the dimensional difference of various molds generated at the time of mold exchange, A sufficient compressive force can be obtained when the mold is closed.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a mold thickness adjusting device for a blow molding machine according to the present invention will be described below in detail with reference to the drawings. Note that the same or equivalent parts as those in the conventional example will be described using the same reference numerals. 1 and 2 show a mold thickness adjusting device of a hollow molding machine according to the present invention. FIG. 1 is a configuration diagram showing an entire configuration, and FIG. 2 is an enlarged configuration diagram showing a main part of FIG.

The configuration shown in FIG. 1 is almost the same as the configuration shown in FIGS. 3 and 4 of the conventional example, and the parts omitted in FIG. 1 are the same as those shown in FIGS. And In FIG. 1, reference numeral 1 denotes a first mold part 2.
And a second mold part 3 which is openable and closable. The parison 6 hanging from the crosshead 5 of the extruder 4 is supplied into the cavity 1 a of the mold 1. .

The second mold part 3 is connected to a toggle mechanism 9 having a pair of bendable first and second toggle pieces 7, 8 via a first mold holder 10 and a first clevis 7a. A guide block 12 holding a shaft support 11 to which the toggle pieces 7 and 8 are connected in a freely bendable manner is configured to be guided by a pair of center positioning guide bars 13 and 14.

The guide block 12 is configured to be rotated by an electric motor 15 and reciprocated in the axial direction by a feed screw 16 such as a ball screw screwed into a screw hole 12a of the guide block 12, and the first mold is provided. The part 2 is provided with a second mold holder 17.

A pair of rods 19 and 20 are connected to a rear plate 18 connected to the second toggle piece 8 via a second clevis 8a.
It is fixedly connected to the first connection body 21 connected to the mold holder 17.

In a pair of clevis recesses 8aA formed in the second clevis 8a and a pair of rear plate recesses 18a formed in the rear plate 18, an elastic body 30 made of a disc spring is provided in a compressed state. The second clevis 8a and the rear plate 18 are urged in a direction away from each other by a restoring force due to the elastic force of the elastic body 30 to have a mold thickness adjustment D consisting of a gap.

A pair of bolts 31 provided on the second clevis 8a are connected to the clevis recess 8aA, the elastic body 30,
The second clevis 8a and the rear plate are formed by penetrating the rear plate recess 18a and the rear plate 18 and projecting outward from the rear plate 18. 18
Are connected to each other via the mold thickness adjustment D. Accordingly, the fastening means 40 is constituted by the bolt 31 and the nut 32, and by rotating the nut 32, the mold thickness adjustment D can be freely adjusted.

A guide pin 33 is provided at a position between the bolts 31 in the second clevis 8a. The guide pin 33 is inserted into a guide hole 34a of a guide member 34 provided in the rear plate 18. Yes, second
The positioning guide when the clevis 8a and the rear plate 18 move are achieved by the guide pins 33 and the guide members 34.

Accordingly, in the above configuration, the electric motor 1
5 and the guide block 12 is moved by the feed screw 16 so that the toggle pieces 7, 8 are positioned as shown by the dotted and solid lines as shown in FIG. The mold portions 2 and 3 are closed in the case of a straight shape, and the mold portions 2 and 3 are opened in the case of a bent shape.

When the mold 1 is replaced with another mold having a different thickness, it can be adjusted freely within the range of the adjustment D by the deformation of the elastic body 30. Furthermore, bolt 31
By adjusting the nut 32, the size of the adjustment D can be arbitrarily adjusted within a predetermined elastic force holding range of the elastic body 30. In the above-described embodiment, the case where a disc spring is used as the elastic body 30 has been described. In addition, fastening means 4
In the case of 0, the case where the bolt 31 and the nut 32 are used has been described, but other configurations can be used.

[0024]

The apparatus for adjusting the thickness of a mold of a blow molding machine according to the present invention is constructed as described above, so that the following effects can be obtained. In other words, instead of replacing the spacer each time for the difference in the thickness of the mold that occurs at the time of mold replacement, the mold thickness adjustment is simply variably absorbed by the elastic body and the fastening means. Adjustment can be performed, and prevention of molding errors due to insufficient compression force due to poor adjustment can be effectively achieved.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a mold thickness adjusting device of a blow molding machine according to the present invention.

FIG. 2 is an enlarged configuration diagram showing a main part of FIG.

FIG. 3 is a configuration diagram showing a mold thickness adjusting device of a conventional hollow molding machine.

FIG. 4 is a plan view of FIG. 3;

[Explanation of symbols]

 1 Mold D Mold thickness adjustment 8a Second clevis 8aA Clevis recess 9 Toggle mechanism 15 Electric motor 18 Rear plate 18a Rear plate recess 30 Elastic body 40 Fastening means

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-256420 (JP, A) "Plastic Molding Processing Course Blow Molding" Plastics Age (February 20, 1970), pp. 46 and 47 page

Claims (4)

(57) [Claims] 1. A mold thickness adjusting device for a hollow molding machine wherein opening and closing of a mold (1) and adjustment of the mold thickness are performed via a toggle mechanism (9) which expands and contracts by an electric motor (15). The rear plate (18) of the toggle mechanism (9) and the second clevis (8a)
A mold thickness adjustment part (D) comprising a gap formed therebetween, an elastic body (30) provided between the rear plate (18) and the second clevis (8a), and the rear plate (18). And the second clevis (8
a) and fastening means for fastening via the elastic body (30)
(40) A mold thickness adjusting device for a hollow molding machine, comprising: 2. The elastic body (30) is held by a clevis recess (8aA) formed in the second clevis (8a) and a rear plate recess (18a) formed in the rear plate (18). The mold thickness adjusting device for a blow molding machine according to claim 1, wherein: 3. The apparatus according to claim 1, wherein said elastic body (30) is formed of a disc spring. 4. A guide pin (33) provided on the second clevis (8a) is inserted into a guide hole (34a) of a guide member (34) provided on the rear plate (18), and 4. The apparatus according to claim 1, wherein when the two clevises (8a) and the rear plate (18) move, positioning guide is performed by the guide pins (33) and the guide members (34). A mold thickness adjusting device for the hollow molding machine as described in the above.