JPH06278198A - Rotary blow molding device - Google Patents

Abstract

PURPOSE:To improve a mold to have a high opening and closing speed, a high productivity, and a small size. CONSTITUTION:A rotary blow molding device is provided with a split type mold 4 to be mold closed, mold clamped and mold opened by a plurality of mold clamping mechanisms disposed along the periphery of a rotating ring 3. A mold clamping mechanism comprises first to third slide components 10, 11 and 12 guided by a slide shaft 8a of a table 8 and moved reciprocatingly, and the first and second slide components 10 and 12 are connected together by a connecting component 9 and moved reciprocatingly and integrally, while a rack section 14a of the third component 11 between the above-said two components is communicated and connected with a rack section 14b of the second slide component 12 through a pinion 15, and moved reciprocatingly in the reverse direction each other to open and close a mold. A mold lock mechanism consisting of lock pieces 24a and 25b to be brought into contact with each other when communicating plates 22 and 23 moved by lock cam mechanisms 20 and 21 are lifted up to the locking positions is provided between the second slide component 12 and the third slide component 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary blow molding apparatus for continuously blow molding hollow molded articles such as plastic containers.

[0002]

2. Description of the Related Art Heretofore, as a rotary blow molding apparatus of this type, the following (a) and (b) are known.

(A) As shown in FIG. 6, a plurality of split molds 101 that can be opened and closed are arranged at equal intervals around a rotor that rotates about a rotation axis, and a mold clamping mechanism for the split molds 101 is provided. As a cam mechanism 1 arranged on both sides of the split mold 101
A mold is clamped by opening and closing by a toggle mechanism 104 driven by 05 and 106, and pressing one mold attached to the mold plate 102 by the hydraulic cylinder 103 toward the other mold (Japanese Patent Laid-Open No. Sho 63-63). -297025
Issue).

(B) As shown in FIG. 7, in a rotary blow molding machine in which a plurality of split molds 209 that can be freely opened and closed are arranged at equal intervals around a rotor 202 that rotates about a rotary shaft 201, As a tightening mechanism, a pair of left and right toggles driven by a cam mechanism including a cam 203 that fixes the split mold 209 to a machine frame and a cam follower 204 that reciprocates in the radial direction of the rotor 202 following the cam surface thereof. One that is opened and closed by a mechanism 206, and one mold attached to one holder 210 is pressed toward the other mold by a hydraulic cylinder 208 provided on one slider 207 to perform mold clamping (JP-A-2-6119). (See the official gazette).

[0005]

Among the above-mentioned conventional techniques, (a) uses a pair of cams as a mold clamping mechanism of the mold, so that if the shape accuracy of both cams is incorrect, the mold will be damaged. Blow molding cannot be performed smoothly because the opening and closing timing is shifted. Therefore, there is a problem in that the shape accuracy of both cams must be high, the number of parts is large, and the manufacturing cost is high.

Further, in (b), although the above-mentioned problem of (a) is solved, since it is necessary to lock the mold at or near the dead point of the toggle mechanism, the speed of opening and closing of the mold is increased. It becomes extremely late near the dead center. As a result, there is a problem that the productivity of the rotary blow molding machine becomes low.

Furthermore, the toggle mechanism of the above conventional one is
Although the directions of the points of action are different from each other, if the mold clamping mechanism is operated at high speed, the movement itself becomes unreasonable, and there is a problem in that it does not operate smoothly.

The present invention has been made in view of the problems of the above-mentioned prior art, and realizes a rotary blow molding apparatus which has a high mold opening / closing speed, high productivity, and can be miniaturized. The purpose is to do.

[0009]

In order to achieve the above object, a rotary blow molding apparatus of the present invention comprises a rotary wheel rotated about a rotary shaft and a plurality of sets arranged around the rotary wheel. In a rotary blow molding machine including a mold clamping mechanism and a split mold for sequentially closing, mold clamping and opening by the mold clamping mechanism, the mold clamping mechanisms are integrally coupled to each other with a gap. A first and a second slide member, and a third slide member disposed between them, and the pair of slide members and the third slide member are driven by a reciprocating drive means. The structure is configured to open and close the mold by reciprocating in opposite directions by an and pinion mechanism, and one of the third slide member and the first and second slide members. It is characterized in that the mold locking mechanism disposed between.

Further, it is effective to dispose a cylinder operated by a pressurized gas for clamping the mold in one of the first and second slide members.

Further, the die lock mechanism includes an interlocking plate reciprocally moved in a direction perpendicular to the opening / closing direction of the die by the locking cam mechanism, one of the first and second slide members and the third slide member. And a locking groove projecting from the slide member so as to oppose each other, and the interlocking plate is configured to be engaged and locked between the leading edges of the locking piece, or the interlocking plate is a guide groove provided in the guide plate. It is preferable that the interlocking plate is configured to move by being guided by, or the interlocking plate is made up of a plurality of plate members of two or more, and lock pieces are provided corresponding to each plate member.

[0012]

The first and second slide members and the third slide member disposed between the first and second slide members are reciprocally moved in opposite directions by the rack and pinion mechanism, so that the mold can be operated at high speed. It can be opened and closed. Also, since it is locked by the mold locking mechanism when clamping the mold,
The reaction force of the mold clamping force does not directly act on the reciprocating drive means of the and pinion mechanism.

[0013]

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a front view of a rotary blow molding apparatus according to an embodiment of the present invention.

The rotary 1 has a rotary wheel 3 integrally provided on a rotary shaft 2, a plurality of sets of mold clamping mechanisms arranged on the outer peripheral surface of the rotary wheel 3 at equal intervals, and a mold clamping mechanism. The mold 4 is provided with a split-type mold 4 that is closed, clamped, and opened, and is rotated by a motor (not shown) to a parison 6 that is extruded from an extrusion head 5 of an extruder. The hollow mold is continuously blow-molded by sequentially closing the mold, closing the mold, and opening the mold.

As shown in FIG. 2, the mold clamping mechanism includes a rotary wheel 3
Of the U-shaped base plate 8 fixed to the peripheral surface of the base plate and a pair of slide shafts 8a parallel to the rotary shaft 2 fixed to the base plate 8 and reciprocating in the axial direction. 3 slide members 10, 11 and 12, and the first and second slide members 10 and 12 on both sides are integrally connected to each other by a connecting member 9 and reciprocally move integrally, and the third slide member 10 between them. The rack member 14a of the slide member 11 of FIG.
It is interlocked and connected to the rack portion 14b of the second slide member 12 through 5, and is configured to reciprocate in the opposite direction to the first and second slide members 10 and 12.

Four support rods 13a projecting from the platen 13 are slidably fitted into the four guide holes of the first slide member 10, and the support rods 13a and the first slides are slidably inserted. Spring 13b interposed between the outer surface of member 10 and
Thus, the platen 13 and the first slide member 10 are constantly urged so as to come into close contact with each other. Further, the first slide member 10 is attached with an air cylinder 7 as a cylinder operated by a pressurized gas for clamping the die 4, and its rod is connected to the platen 13. .

Furthermore, the second slide member 12 reciprocates in the same direction as the slide shaft 8a following the cam surface of the cam 16 as a reciprocating drive means for driving the rack and pinion mechanism. One end side of the cam follower 17 is connected.

Next, the mold lock mechanism will be described.

As shown in FIGS. 2 and 3, the mold locking mechanism is constructed as follows.

A lock cam mechanism comprising a lock cam 20 and a lock cam follower 21 that follows the shape of the cam surface, and a pair of upper and lower interlocking plates 22 and 23 fixed to the lock cam follower 21. The interlocking plates 22 and 23 are provided with slits 22a formed at their four corners,
A pair of guide plates 18 and 19 of which 23a is projected on the second slide member 12 and a pair of guide plates 26 and 27 which are projected on the third slide member 11 are loosely fitted. The guide plates 26, 2 are provided in the slits 22a, 23a, respectively.
A pin (not shown) projecting from 7 is projected, and the pin is engaged with a pair of upper and lower L-shaped guide grooves 25a, 25b formed in each guide plate 18, 19, 26, 27.
Needless to say, the guide grooves 25a and 25b are such that when the interlocking plates 22 and 23 are pulled up to the lock position, the end faces at the four corners of the interlocking plates 22 and 23 are a pair of upper and lower lock pieces 24a, respectively. The guide is provided so as to come into contact with the leading edge of 25b.

The number of interlocking plates is not limited to two, and one or three or more can be provided, and lock pieces can be provided corresponding to each plate, but two or more interlocking plates can be provided around the center of the mold. It is possible to obtain a locked state that is efficient to place. Also, the interlocking plate 4
Instead of contacting the end faces of the corners with the leading edges of the lock pieces, lock blocks are fixed between the guide plates, and the leading edge of the center part of the interlocking plate contacts the surface. You can also do it.

Next, the operation of this embodiment will be described.

FIG. 3 is a cross-sectional view of a main part showing a state where the mold 4 is opened.

As the rotary 1 rotates from the mold open state shown in FIG. 3, the cam follower 17 follows the shape of the cam 16 and moves to the right in the figure, and the second slide member 12 is moved.
And the 1st slide member 10 integrated with this is moved to the right in the figure. At this time, the rack portion 14 b of the second slide member 12 and the rack portion 14 of the third slide member 11
The third slide member 11 is moved leftward in the drawing by a rack and pinion mechanism including a and a pinion 15. That is, the mold is closed, and as shown in FIG.
It reaches a position where a slight gap is formed between the one die 4a and the other die 4b.

When the lock position shown in FIG. 4 is reached, the lock cam follower 21 follows the lock cam 20 and is pulled up.
23 is guided by the guide grooves 25a and 25b and pulled up, and the leading edges of the four corners of the interlocking plates 22 and 23 are set to the lock pieces 2 respectively.
4a, 24b engaged with the front edge of each slide member 10,
11 and 12 are locked.

Next, as shown in FIG. 5, the air cylinder 7 is actuated to resist the elastic force of the spring 13b and the platen 13 together with one mold 4a and the other mold 4a.
Press to b and clamp.

On the other hand, when the mold is opened, the pressure applied by the air cylinder 7 is first released, and the lock cam follower 21 is pushed downward by the cam surface of the lock cam 20 to push up the interlocking plates 22 and 23 to lock the lock pieces. To disengage from.

Then, by moving the cam follower 17 in the opposite direction (left side in the drawing) from the cam surface of the cam 16, the respective slide members are moved in the opposite direction to that in the mold clamping and one of the metal members is moved. The mold 4a and the other mold 4b are separated from each other, and the mold is opened.

[0030]

Since the present invention is configured as described above, it has the following effects.

Since the mold is locked by the mold locking mechanism during mold clamping, the reaction force of the mold clamping force does not act on the reciprocating drive means for driving the rack and pinion mechanism. In addition, since the direction of the force applied to each slide member or the like at the time of opening and closing the mold and closing the mold is only one direction, the mechanical strength calculation can be rigorous, and each part can be downsized.

Further, since the rack-and-pinion mechanism is used as the mold clamping mechanism, the mold can be opened and closed more quickly and smoothly as compared with the toggle mechanism, and the productivity of the rotary blow molding machine is improved.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of a rotary blow molding apparatus of the present invention.

FIG. 2 is a partial perspective view of a main part of the rotary blow molding apparatus according to the present invention.

FIG. 3 is a cross-sectional view showing a part of the rotary blow molding apparatus according to the present invention and showing a state where the mold is opened.

FIG. 4 is a sectional view showing a part of the rotary blow molding apparatus according to the present invention, showing a state immediately before the mold is closed and clamped.

FIG. 5 is a cross-sectional view showing a part of the rotary blow molding apparatus according to the present invention and showing a state where the mold is clamped.

FIG. 6 is an explanatory diagram showing a main part of an example of a conventional rotary blow molding apparatus.

FIG. 7 is an explanatory diagram showing a main part of another example of a conventional rotary blow molding device.

[Explanation of symbols]

 1 Rotary 2 Rotating Shaft 3 Rotating Wheel 4 Mold 5 Extrusion Head 7 Air Cylinder 8 Platform 8a Slide Shaft 9 Connecting Member 10 First Sliding Member 11 Third Sliding Member 12 Second Sliding Member 13 Platen 14a, 14b Rack Part 15 Pinion 16 Cam 17 Cam follower 18, 19 Guide plate 18a, 18b Guide groove 20 Locking cam 21 Locking cam follower 22, 23 Interlocking plate

Claims (7)

[Claims] 1. A rotary wheel rotated about a rotary shaft, a plurality of sets of mold clamping mechanisms arranged around the rotary wheel, and mold closing, mold clamping and mold opening sequentially by the mold clamping mechanism. In a rotary blow molding machine provided with a split-type mold, the mold clamping mechanism includes a first and a second slide member that are integrally connected to each other at a distance, and a third slide member that is disposed between the first and second slide members. The pair of slide members and the third slide member are reciprocally moved in opposite directions by a rack and pinion mechanism driven by a reciprocating drive means to open and close the mold. And a mold lock mechanism disposed between the third slide member and one of the first and second slide members. 2. A cylinder, which is operated by a pressurized gas for clamping a mold, is provided on either one of the first and second slide members. Rotary blow molding equipment. 3. The interlocking plate reciprocally moved in a direction perpendicular to the opening / closing direction of the die by a locking cam mechanism, one of the first and second slide members, and a third die locking mechanism. 3. A rotary member according to claim 1 or 2, wherein the rotary member is composed of a lock piece projecting oppositely from the slide member, and is configured to engage and lock the interlocking plate between the front edges of the lock piece. Blow molding equipment. 4. The rotary blow molding apparatus according to claim 3, wherein the interlocking plate is configured to move while being guided by a guide groove provided in the guide plate. 5. The rotary blow molding apparatus according to claim 4, wherein the guide groove is formed in an L shape. 6. The rotary blower according to claim 3, wherein the interlocking plate is composed of a plurality of two or more plate bodies, and lock pieces are provided corresponding to the respective plate bodies. Molding equipment. 7. The rotary blow molding apparatus according to claim 1, wherein the reciprocating driving means is a cam mechanism.