JP2003039537A - Mold clamping device of hollow holding machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mold clamping device of a hollow molding machine which efficiently imparts a mold clamping force and a dwell pressure required for a molding tool to a mold in compliance with the size and shape of the molding tool. SOLUTION: This mold clamping device of a hollow molding machine is constituted of a plurality of tie bars 14, 15 and 16 inserted through an appropriate movable table 13, a forward platen support plate 2, a rear support plate 3 and a pair of platens 4 and 5 with a pair of fitted mutually counter-facing molding tools 6 and 7 and a mold clamping drive mechanism 9 which makes a pair of molding tools perform actions such as the clamping, dwelling and opening of a mold. The forward platen 4 is fitted, in a freely rotating manner, to the upper end part of the forward platen support plate 2, with the help of a leg-shape forward bracket 40 which is hinged to the upper end part and has an upper and a lower support 402. Further, the rear platen 5 is fitted, in a freely rotating manner, to a link arm 91 positioned forward of the mold clamping drive mechanism 9, with the help of a leg-shape rear bracket 50 which is hinged to the link arm 91 and has an upper and a lower support 502.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold clamping device for a hollow molding machine, and more particularly, to a mold clamping force and holding pressure required for the mold corresponding to the shape of the mold. TECHNICAL FIELD The present invention relates to a mold clamping device of a hollow molding machine that can be imparted to the mold.

[0002]

2. Description of the Related Art A hollow molding machine for molding a hollow molded article introduces a parison discharged from an extruder die into a molding die and blows air into the parison to engrave the inner surface of the molding die. A hollow molded product is molded by the cavity described above, and a mold clamping device for closing or opening the mold is provided.

The mold clamping device includes a plurality of tie bars inserted into an appropriate movable table, a front platen support plate and a rear support plate fixed to the tie bars, and a slide collar slidably inserted into the tie bars. And a parting line holding mechanism that moves the pair of platens at equal distances to each other and holds them, and a pair of molding dies facing each other closes and holds
It is composed of a mold clamping drive mechanism for performing a mold opening operation.

In this mold clamping device, a guide rail is laid on the upper surface of a slide base fixedly installed on a main body base, and an appropriate movable base is slidably mounted on the guide rail, and a plurality of, for example, 3 units are mounted on the movable base. The book tie bars are inserted and supported horizontally in an inverted triangular arrangement so that they can move axially, and the front platen support plate is fixed to one end of these tie bars, and the rear support plate is fixed to the other end thereof at right angles. I am doing it.

Of the pair of platens, the front platen is connected to the front slide collar slidably inserted in the tie bar, and rotatably connected to the upper end of the front platen support plate via a shaft. It is attached by making surface contact with the bracket. Further, the rear platen is connected to a rear slide collar slidably inserted in the tie bar, and a surface of a bracket rotatably connected to a front link arm of a mold clamping drive mechanism described later through a shaft. Contacted and attached. A pair of molding dies are attached to the front platen and the rear platen so as to face each other.

In the parting line holding mechanism, plate-shaped or bar-shaped racks are horizontally extended through slides on the slide collars of the front and rear platens, and the racks are rotatably mounted on a movable table. The pinion is supported and meshes with it. Therefore, when the pinion rotates, the racks move in the left-right direction (directions of the front platen and the rear platen) at equal lengths, respectively, and as a result, the pair of platens and the molding dies attached to the platens are mutually centered. Parting line P. L
It has a mechanism to move toward.

Between the rear platen and the rear support plate, a mold clamping drive mechanism for interposing a pair of molding dies facing each other for performing mold closing, pressure holding and mold opening operations is connected.

The mold clamping drive mechanism is composed of a slide block composed of a disk rotated by an electric motor connected to a drive shaft and a pair of link arms rotatably connected to the disk so as to face each other in the diametrical direction. . The disk is rotatably supported by a slide block about an axis, and the slide block is uprightly connected to a slide collar that is horizontally movably inserted through a tie bar.

One end of one link arm is rotatably connected to the disk via a shaft, and the other end is rotatably connected via a bracket attached to the rear surface of the rear platen. Further, one end of the other link arm is rotatably connected to the shaft via a shaft that is diametrically opposed to the shaft, and a mold clamping force generating mechanism is provided at the other end. The mold clamping force generating mechanism rotatably connects the shaft to the other end of the other link arm via a shaft, and the shaft is axially movably inserted into a cylinder provided at the upper end of the rear support plate. In the cylinder, a plurality of disc springs penetrating the shaft are arranged and housed with their concave surfaces facing each other so that they can be compressed.

[0010]

In the mold clamping device of such a hollow molding machine, the mounting of the molding die on the platen is usually performed by the surplus portion () of the parison generated in the hollow molded product to be molded. The upper surface of the molding die is mounted flush with the upper surface of the platen in order to reduce the burrs and to minimize the required parison length.

Further, the attachment of the front platen support plate to the front platen and the attachment of the link arm to the rear platen are usually positioned slightly above the vertical center of the front platen and the rear platen so that a larger force acts. In addition, a planar bracket is configured to be in surface contact without a gap with or without a flat plate or the like. Therefore, when the vertical center of the molding die matches the vertical mounting position of the front platen support plate with respect to the front platen and the vertical mounting position of the link arm with respect to the rear platen, respectively The tightening force / holding force is most effective.

However, depending on the shape of the hollow molded product to be molded, the molding die may become smaller or larger in the vertical direction.

When the molding die is downsized in the vertical direction, the bottom of the molding die is above the front platen and the rear platen, and depending on the shape of the hollow molding, the bottom of the molding die is a bracket for the front platen and the rear platen. This is a mode in which the position is higher than the mounting position of. In this case, when the molding die containing the hollow molded product obtained by bulging the parison is clamped, the action point of the mold clamping force / holding force becomes unbalanced between the upper and lower parts of the molding die, and the action point. Since the lower part of the molding die becomes stronger, the mold clamping force and holding pressure required for the upper part of the molding die will not be applied, and phenomena such as deformation at the upper part of the hollow molded product, such as a slight opening of the plug part, will occur. Therefore, the surplus part (burrs) of the parison may not be eaten (cut) sufficiently.

When the molding die becomes large vertically, the bottom of the molding die is below the front platen and the rear platen, and depending on the shape of the hollow molding, the bottom of the molding die is the front platen and the rear platen. It becomes a mode in which it is located in the lower part of the platen. In this case, when the molding die containing the hollow molded product obtained by bulging the parison is clamped, the action points of the mold clamping force and the holding pressure are unbalanced between the upper and lower positions like the former, and the action point is Since the upper part of the molding die becomes stronger, the clamping force / holding force of the lower part of the molding die becomes weaker by that amount, and the excess part (burr) of the parison at the lower part of the hollow molded product is sufficiently cut (pushed). It happens that you don't.

The present invention is a hollow molding process in which the points of action of the mold clamping force and holding pressure are worked in a well-balanced manner in accordance with the size and shape of the molding mold to mold a hollow molded product of good quality. To provide a mold clamping device for a machine.

[0016]

In order to solve the above-mentioned conventional technical problems, the invention according to claim 1 is such that a tie bar movably inserted in a movable table in a horizontal direction and a front end of the tie bar. A fixed front platen support plate,
A rear support plate fixed to the rear end of the tie bar, a front platen and a rear platen slidably inserted into the tie bar via a slide collar, and having a molding die attached thereto, and the front and rear platens. Part line holding mechanism for moving and holding the same at a predetermined parting line with respect to each other, and a mold clamping drive mechanism movably inserted in the tie bar via a slide collar between the rear platen and the rear support plate. A mold clamping device for a hollow molding machine comprising: a front platen, which is rotatably supported by an upper bracket of a front platen support plate, and a leg-shaped front bracket having at least upper and lower support parts pivotally attached to the front platen. Attach the rear platen to the front link arm of the mold clamping Behind the bracket legs shape having a lifting portion, it is characterized in that it has attached rotatably.

According to a second aspect of the present invention, in the mold clamping device for a hollow molding machine according to the first aspect, the front and rear brackets have upper and lower support portions, and the distance between the support portions in the vertical direction is small. It is characterized by being variable.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a mold clamping device of a hollow molding machine according to the present invention will be described in detail below with reference to the drawings.

That is, the mold clamping device of this hollow molding machine is
As shown in FIG. 1, a plurality of tie bars 14, 15, 16 inserted into an appropriate movable base 13 and tie bars 14, 15,
The front platen support plate 2 and the rear support plate 3 fixed to 16 and the slide collars 42, 43, 52 and 53 slidably inserted in the tie bars 14, 15 and 16 are connected to each other to form a pair of molding dies 6. , 7 attached to the front platen 4 and the rear platen 5, a parting line holding mechanism 8 for moving and holding the front platen 4 and the rear platen 5 at equal distances from each other, and a pair of molding dies 6 and 7 facing each other. Is composed of a mold clamping drive mechanism 9 for performing mold closing, pressure holding, and mold opening operations.

In this mold clamping device, a guide rail 12 is laid on the upper surface of a slide base 11 fixedly installed on the main body base 1, an appropriate movable base 13 is slidably mounted on the guide rail 12, and this movable base is mounted. A plurality of, for example, three tie bars 14, 15 and 16 are inserted into and supported by 13 in an inverted triangular arrangement so as to be movable horizontally and axially.
The front platen support plate 2 is orthogonally fixed to one end of the back plate 4, 15, 16 and the rear support plate 3 is attached to the other end thereof.
Are orthogonally fixed.

The front platen 4 is connected to front slide collars 42 and 43 slidably inserted in the tie bars 14 and 15, and a shaft 21 is attached to an upper end portion of the front platen support plate 2.
Upper and lower support parts 402, 40 rotatably connected via
It is attached by being supported / contacted to a leg-shaped bracket 40 having two.

The rear platen 5 includes a tie bar 14,
15. A rear slide collar 52 slidably inserted in 15,
53, and is supported by a leg-shaped bracket 50 having upper and lower support portions 502, 502 that are rotatably connected to a front link arm 91 of a mold clamping drive mechanism 9 described later in detail via a shaft 911. Contacted and attached.
A pair of molding dies 6 and 7 are attached to the front platen 4 and the rear platen 5 so as to face each other. 6
Reference numerals 1 and 71 are stoppers and are provided so as not to be cantilever when a small forming die is used.

In the parting line holding mechanism 8, a pair of plate-shaped or bar-shaped racks 81, 81 are horizontally arranged on the slide collars 42, 43, 52, 53 of the front platen 4 and the rear platen 5 via supports. It is provided by extending,
The pair of racks 81 and 81 face and mesh with a pinion 82 that is rotatably supported by the movable base 13.

With these, the mold clamping drive mechanism 9 to be described later
When the electric motor (not shown) is controlled and rotated, the drive shaft 93 rotates, and this rotation causes the disk 94 to rotate and move the pair of link arms 91 and 92 so as to face each other horizontally. As a result, the front platen 4, the front platen support plate 2, and the rear support plate 3 move leftward in the figure, and at the same time, the rear platen 5 moves rightward in the figure.

By moving the front platen 4 to the left and moving the rear platen 5 to the right, the pair of racks 81, 81 connected to the platens 4, 5 move to the right and left, respectively. The pinion 82 rotates, and as a result, the molding dies 6 and 7 attached to the platens 4 and 5 are separated from each other by the parting line P. It will move toward L.

The mold clamping drive mechanism 9 is interposed and connected between the rear platen 5 and the rear support plate 3, and a pair of molding dies 6 and 7 facing each other perform mold closing, pressure holding, and mold opening operations. Is something that

The mold clamping drive mechanism 9 is rotated by an electric motor (not shown) connected to a drive shaft 93.
4 and a pair of link arms 91 and 92 which are diametrically opposed to each other and are rotatably connected to each other. The disk 94 is rotatably supported by a slide block 95 about a shaft 93, and the slide block 95 is uprightly connected to a slide collar 96 which is inserted through the tie bars 14 and 15 so as to be horizontally movable. .

One end of one link arm 91 is rotatably connected to the disk 94 via a shaft, and the other end thereof is rotatably connected via a bracket 50 attached to the rear surface of the rear platen 5. It is connected. Further, one end of the other link arm 92 is rotatably connected to the shaft via a shaft that is diametrically opposed to the shaft, and a mold clamping force generating mechanism 10 is provided at the other end of the link arm 92.

The mold clamping force generating mechanism 10 rotatably connects a shaft 97 to the other end of the other link arm 92 via a shaft 921, and the shaft 97 is attached to the rear support plate 3.
A plurality of disc springs 100 inserted into a cylinder 101 provided at the upper end of the cylinder 101 so as to be movable in the axial direction and penetrating the shaft 97 are arranged and housed with their concave surfaces facing each other so that they can be compressed. .

The leg-shaped brackets 40 and 50 having upper and lower supporting portions are provided on the rear surface of the platens 4 and 5 (molding die 6,
7 and the upper and lower support portions 402 having a supporting surface sufficient to transmit the mold clamping force / holding force at the time of mold clamping as shown in FIG. , 50
2 is formed of a leg-shaped metal rectangular parallelepiped 40 having a predetermined width.
1,501. This metal rectangular parallelepiped 401, 50
1 or a plurality of 1 and 2 to 4 as one set according to the platen and the molding die, with appropriate intervals, at the center position in the width direction of the platens 4 and 5 and the center in the height direction. The brackets 40 and 50 are used at a slightly higher position.

This bracket may be in a form in which a plurality of leg-shaped metal rectangular parallelepipeds each having a predetermined width are integrally connected by a connecting member with an appropriate interval.

403 and 503 are bolt holes for attaching the brackets 40 and 50 to the platens 4,5 from the platen 4,5 side, and 404 and 504 are front platen support plate 2 and rear support plate 3 respectively. It is a through hole for inserting the shaft 21 and the shaft 911.

The operation of this mold clamping device will be described below.

First, the parison (not shown) discharged from the die of the extruder is introduced into the molding dies 6 and 7, and after the parison is introduced, the molding dies 6 and 7 are electrically driven by the mold clamping drive mechanism 9. A motor (not shown) is driven to apply a mold clamping force / holding pressure to the molding dies 6 and 7, and the molds are closed.
Air is blown into the parison in 7 to form a hollow molded product by the cavity formed in the inner surfaces of the molding dies 6 and 7. After holding the molding dies 6 and 7 in a closed state for a predetermined time, the molding dies 6 and 7 are opened.

In this embodiment, the front platen 4 and the rear platen 5 are at least vertically supported by the support portion 40.
Since it is rotatably attached by the leg-shaped brackets 40, 50 having 2, 502, the molding dies 6, 7 which are small in the vertical direction are formed by the front platen 4 and the rear platen 5 as shown in FIG. Mounted above the
As shown in FIG. 3, the mold clamping force / holding force applied to the center points of the brackets 40 and 50 is divided into a component force R1 and a component force R2, and the component force R1 is a force F × length L2 × 1. / (Length L
From the relationship of 1 + length L2), if L2 is increased, R1 is increased and the mold clamping force can be effectively used. In addition, the amount of vertical deflection of the platens 4 and 5 can be reduced compared to the case where a conventional bracket that is attached by surface contact is used. Depending on the allowable amount of deflection, the thickness of the platen can be reduced. The platen can be quantified.

That is, the imbalance of the action points of the mold clamping force and the holding pressure, which occurs when the molding die becomes small in size in the vertical direction, is alleviated, and a phenomenon such as deformation at the upper portion of the hollow molding product, such as a plug. A hollow molded article of good quality can be molded by preventing a phenomenon such as a slight opening of the parison and not sufficiently cutting (cutting) the surplus portion (burr) of the parison.

Further, when a large molding die is arranged in the vertical direction to a position substantially below the front and rear platens and attached, the mold clamping force applied to the center point of a leg-shaped bracket having upper and lower supporting portions.・ The holding pressure is divided into the upper and lower support parts by being divided into components as in the above, and the mold clamping force can be effectively used. Relief (loss) such as mold clamping force due to deformation is reduced and mold clamping force etc. is required at the upper and bottom parts of hollow molded products where mold clamping force is more required. Therefore, the hollow molded product of good quality can be molded by sufficiently cutting (pushing) excess portions (burrs) at the upper part and the bottom of the hollow molded product.

FIG. 4 shows another embodiment of the present invention. FIG. 4 shows a main part of the mold clamping device, which is inserted into an appropriate movable table (not shown). Front platen support plate 2 fixed to the plurality of tie bars 14, 15, 16 (not shown) and slide collars 42, 43, 52, 5 slidably inserted into the tie bars 14, 15.
A mold for connecting the front platen 4 and the rear platen 5 to which the pair of molding dies 6 and 7 are attached, and the pair of molding dies 6 and 7 facing each other to perform mold closing, pressure holding, and mold opening operations. It is composed of a tightening drive mechanism 9. The other parts of the mold clamping device have substantially the same structure as the above-mentioned embodiment.

As shown in FIG. 4, the front bracket 41 for mounting the front platen 4 on the front platen support plate 2 and the rear bracket 51 for mounting the rear platen on the link arm 91 of the mold clamping drive mechanism 9 have upper and lower support portions as shown in FIG. It has a leg shape, and the upper support part has a support surface and is fixed support parts 412 and 512 that are integrated with the bracket body, and the lower support part has a support surface and in the vertical direction thereof. The variable support parts 411 and 511 have adjustable positions.

In FIG. 4, in the front bracket 41 and the rear bracket 51, the variable support portions 411 and 511 are T-groove-shaped or dovetail grooves formed in the lower side surfaces of the fixed support portions 412 and 512 in the vertical direction. Can be slid vertically by being fitted in the concave groove, and the vertical position can be adjusted by position adjusting rods 413, 513 such as bolts provided on the fixed support portions 412, 512. . After the positions of the brackets 41 and 51 are adjusted, the brackets 41 and 51 are attached to the platens 4 and 5 by bolts inserted into the long holes.

In contrast to the above, the upper supporting portion of the bracket may be a variable supporting body and the lower supporting portion of the bracket may be a fixed supporting portion, and the upper supporting portion and the lower supporting portion of the bracket may be different. Both of them are variable supports that are slidably fitted in concave grooves formed in the bracket body,
This may be attached to the platen with bolts or the like so that the position can be adjusted.

In short, the front bracket and the rear bracket have support portions formed above and below,
It suffices that the vertical positions of the upper support and the lower support can be adjusted, and the distance between the upper support and the lower support can be changed. The operation of this mold clamping device will be described.

Prior to the hollow molding, the lower variable support parts 411, 511 mounted on the front bracket 41 and the rear bracket 51 are fitted to the sizes of the molding dies 6, 7.
Is adjusted in the vertical direction by the bolt-shaped position adjusting rods 413 and 513.

When using a small molding die in the vertical direction,
The positions of the variable support portions 411 and 511 of the front bracket 41 and the rear bracket 51 are set to the bolt-shaped position adjustment rod 41.
3, 513 moves and adjusts downward according to the positions of the stoppers 62, 72 and the bottoms of the molding dies 6, 7.

In this state, the parison (not shown) discharged from the die of the extruder is introduced into the molding dies 6 and 7,
After introducing the parison, the molding dies 6 and 7 are driven by an electric motor (not shown) of a mold clamping drive mechanism to apply a mold clamping force / holding pressure to the molding dies 6 and 7 to perform mold clamping. Air is blown into the parison in the molding dies 6 and 7 to form the molding dies 6 and 7.
A hollow molded product is molded by the cavity engraved on the inner surface of the. After holding the molding dies 6 and 7 in a clamped state for a predetermined time, the molding dies 6 and 7 are opened. In the present embodiment, the positions of the variable support portions 411 and 511 below the front bracket 41 and the rear bracket 51 are adjusted according to the sizes of the molding dies 6 and 7, so that the front bracket 41 and The mold clamping force / holding force applied to the fulcrum of the rear bracket 51 is divided by the upper fixed support portions 412 and 512 and the lower variable support portions 411 and 511, and is passed through the front platen 4 and the rear platen 5 to form the molding dies 6. 7
This effectively alleviates the bias of the action point to the lower side of the molding die as in the conventional case, so that the clamping force of the molding dies 6 and 7 can be effectively used.

That is, the balance of the action points of the mold clamping force / holding force and the lack of the mold clamping force, which occur when the molding die becomes smaller in size in the vertical direction, are eliminated, and the hollow molding product is deformed in the upper part. Phenomenon For example, the mouth plug is molded in a slightly open state,
A hollow molded article of good quality can be molded by preventing a phenomenon such as not sufficiently cutting (pushing) the surplus portion (burr) of the parison.

When a large molding die is used, the stoppers attached to it are removed, and the variable support portions of the front bracket and the rear bracket are attached to the upper or lower positions of the molding die. Move or adjust upwards or downwards according to the position where the excess part (burr) of the parison or shoulder or bottom parison is cut (pushed).

As a result, the mold clamping force / holding pressure applied to the center points of the front bracket and the rear bracket is divided by the upper fixed (or variable) support portion and the lower variable (or fixed) support portion in the same manner as described above. As a force, it is effectively applied to the part of the mold that requires mold clamping force / holding force through the front platen and the rear platen, and it is prevented from being biased to one side of the mold and the mold clamping force of the mold is prevented.・ The holding pressure can be used effectively.

That is, the balance of the action points of the mold clamping force / holding force and the lack of the mold clamping force that occur when the molding die becomes large in the vertical direction are eliminated, so that the upper or lower part of the hollow molded product is eliminated. In addition, a phenomenon such as deformation is prevented, for example, a phenomenon in which the surplus portion (burr) of the parison is not sufficiently cut (pushed), and a hollow molded product of good quality can be molded.

[0050]

INDUSTRIAL APPLICABILITY According to the present invention, the action points of the mold clamping force and the holding pressure of the molding die work in a well-balanced manner in accordance with the size and shape of the molding die to form a hollow molded product of good quality. be able to.

[Brief description of drawings]

FIG. 1 is a front view of a mold clamping device of the present invention.

FIG. 2 is a perspective view of the bracket of the present invention.

FIG. 3 is a partially enlarged front view of the mold clamping device of the present invention.

FIG. 4 is a partially enlarged front view of another mold clamping device of the present invention.

[Explanation of symbols]

1 ... Main body base 2 ... Front platen support plate 3 ... Rear support plate 4 ... Front platen 5 ... Rear platen 6,7 ... Mold 8: Parting retention mechanism 9 ... Mold clamping drive mechanism 10 ... Mold clamping mechanism 13 ... Movable platform 14, 15, 16 ... Tie bar 40, 41 ... Front bracket 42, 43 ... Front slide collar 50, 51 ... Rear bracket 52, 53 ... Rear slide collar 91, 92 ... Link arm 401, 501 ... Metal rectangular parallelepiped 402, 502 ... Support section 411, 511 ... Variable support section 412, 512 ... Fixed support portion 413, 513 ... Position adjusting rod PL: Parting line

Claims (2)

[Claims] 1. A tie bar movably inserted through a movable table in a horizontal direction, a front platen support plate fixed to a front end of the tie bar, a rear support plate fixed to a rear end of the tie bar, and the tie bar. A front platen and a rear platen, which are slidably inserted through a slide collar and to which a molding die is attached, and a party which moves the front and rear platens to a predetermined parting line at equal distances from each other and holds them. A mold clamping device of a hollow molding machine, comprising: a clamping line holding mechanism, and a mold clamping drive mechanism that is movably inserted into a tie bar via a slide collar between a rear platen and a rear support plate. , A leg-shaped front bra having at least upper and lower support portions pivotally attached to the upper end portion of the front platen support plate. Rotatably, and the rear platen can be rotatably attached to the front link arm of the mold clamping drive mechanism by a leg-shaped rear bracket having at least upper and lower support portions pivotally attached to the front plate arm. A mold clamping device for a hollow molding machine, characterized in that 2. The mold clamping device for a hollow molding machine according to claim 1, wherein the front and rear brackets have upper and lower support portions, and a vertical distance between the support portions is variable. Clamping device for hollow molding machine.