WO2015036242A1

WO2015036242A1 - Multi-part blow mould, in particular for producing plastic bottles

Info

Publication number: WO2015036242A1
Application number: PCT/EP2014/068156
Authority: WO
Inventors: Dmitrij Sokolov
Original assignee: Röders Gmbh
Priority date: 2013-09-12
Filing date: 2014-08-27
Publication date: 2015-03-19
Also published as: EP3043978A1; DE102013218282A1

Abstract

The invention relates to a multi-part blow mould for the production of blow-moulded workpieces consisting of plastic, with at least one locking mechanism for the releasable locking of an exchangeable insert (1) in a blow mould (2), wherein the locking mechanism comprises multiple clamping pieces (3), which are movable transversely in relation to a longitudinal axis (4) of the exchangeable insert (1) between a release position and a locking position, characterized in that, to allow them to be moved, the clamping pieces (3) are coupled to a slide (5), which is mounted on the blow mould (2) and is movable along the longitudinal axis (4) of the exchangeable insert (1).

Description

Multi-part blow mold, in particular for the production of plastic bottles

description

In the production of blown bottles, e.g. From PET, blow molds are often used in which the forming parts of the blow molds are realized as so-called interchangeable inserts. Such a system is e.g. known from EP 0 821 641 B1. The interchangeable inserts are easily attached and held in a mother mold (blow mold). The aim of this set of blow molds with inserts is a simple and quick change of the forming parts of the blow mold to quickly change from one bottle product to another.

As can be seen from EP 0 821 641 B1, the interchangeable inserts are usually fastened with screws, by means of which the insert is held in the mother mold by means of washers which can be displaced via a slotted hole or washers designed as eccentrics. To replace the exchangeable inserts, the retaining screws only need to be loosened slightly, and then the washers are pushed away or turned away, so that the interchangeable inserts can be removed from the parent mold.

A disadvantage of this type of attachment of the interchangeable inserts in the parent mold is that at least on one side of the parent mold at least 2 screws solved and the associated washers must be moved or rotated to perform the change of the inserts. The US 5 968 560 A shows a construction in which the backup of the exchange insert by means of clamping pieces, which are transversely displaceable to the longitudinal axis of the exchange insert. The individual clamping pieces are each fixed by means of a screw. After loosening the screw, the clamping pieces must each be manually moved individually before they are fixed by means of the screw, in particular in the locking position. This procedure is impractical and error-prone and requires a very high effort to change the exchange insert. The invention has for its object to provide a multi-part blow mold and in particular a quick-release system for quickly changing a replacement insert, which are quick, easy and reliable operable with a simple structure and simple, cost manufacturability. According to the invention the object is achieved by the feature combination of claim 1, the dependent claims show further advantageous embodiments of the invention.

According to the invention, it is thus provided that the locking mechanism for locking the exchange insert of the blow mold comprises a plurality of clamping pieces, which are displaceable transversely to a longitudinal axis of the exchange insert from a release position to a locking position and vice versa. It is provided in particular according to the invention that the clamping pieces are coupled to the displacement of a slider which is movable along the longitudinal axis of the removable insert and mounted on the blow mold.

Due to the inventive design of the locking mechanism, it is thus possible to move by a simple longitudinal movement of the slider several clamping pieces to bring them either in a release position or a locking position. It is therefore not necessary to operate the individual clamping pieces themselves directly. Rather, the shift of the slide, which is operatively connected to the clamping pieces extends. Through this operating connection, a conversion of the longitudinal movement of the disk takes place in each case in a transverse movement of the individual clamping pieces. The embodiment of the invention has a simple, inexpensive construction and in particular requires only very little space. This is especially important for blow molds or exchangeable insert holders, which only provide a limited installation space.

Another, significant advantage of the solution according to the invention is that the individual clamping pieces can be moved simultaneously and synchronously. As a result, operating errors are excluded, since only a longitudinal displacement of the slider is required. This longitudinal displacement of the slider can be done in a very short period of time, so that the time required to replace the replacement insert and to fix another replacement insert can be very short.

In a particularly favorable development of the invention it is provided that the clamping pieces are coupled by means of a sliding guide with the slider. Such link guide is inexpensive and easy to manufacture and has a high level of reliability. The slide guide serves for a positive coupling between the clamping pieces and the slide, so that the longitudinal displacement of the slide is converted directly into a transverse movement of the clamping pieces.

For the design of the slide guide, it is particularly advantageous if these sliding elements comprises, which are arranged at an angle to the direction of displacement of the clamping pieces and the direction of movement of the disk. These sliding elements may for example be designed in the form of ribs, which cooperate with corresponding grooves. Such a configuration is simple and inexpensive and is characterized by a robust, durable construction.

For safe storage of the slide, it is particularly advantageous if it is mounted on a bridge attached to the blow mold. This bridge ensures the longitudinal displacement of the slider, protects it from damage and serves to absorb the required displacement forces for the movement of the slider. It is particularly advantageous if an actuator is arranged between the slide and the blow mold. This can be formed in a favorable embodiment of the invention in the form of an eccentric, which provided with tool engagement means. Thus, it is possible to rotate by means of a tool, for example a hexagonal tool, the eccentric element, in order to move the slider relative to the bridge in this way. In order to securely lock the interchangeable insert on the blow mold, it is particularly advantageous if the clamping piece has a conical cross-sectional area and if, in a favorable development, the bridge is provided with a conical contact surface at least in the region of the clamping pieces. Due to the conical cross-sectional area of the clamping piece this is clamped in the locking position against the changeover insert to lock this free of play with a sufficient biasing force and to fix. By optionally provided on the bridge additional conical contact surface can be carried out an additional jamming and biasing of the clamping pieces. The eccentric element is preferably positively lockable in the bridge drehsicherbar. It may prove to be beneficial to bias the eccentric by means of a spring in the direction of its axis of rotation and to provide suitable recesses in the bridge, in which the eccentric can engage in the respective end position of the displacement of the slider. This prevents the eccentric element from coming off due to vibrations. At the same time, a visual control of the exact positioning of the slider in one of its two end positions can be made to ensure that the clamping pieces are each in the release position or in the locking position. In the following the invention will be described by means of an embodiment in conjunction with the drawing. Showing:

1 is a partial exploded view of a blow mold with interchangeable insert and the locking mechanism according to the invention,

2 is a view similar to FIG. 1 in a modified arrangement,

Fig. 3 is a further exploded view of the arrangement of Figs. 1 and 2 in

changed presentation, Fig. 4 is a detail exploded view of the invention

Locking mechanism, Fig. 5 to 8 detailed views, in sectional view, of the locking mechanism in the closed locking position, and

Fig. 9 to 12 detailed views analogous to FIGS. 5 to 8 in the open release position. FIGS. 1 to 3 each show a perspective view of a part of a blow mold 2 or a transfer carrier. Furthermore, a part of a removable insert 1 is shown, which forms a cavity for the production of a bottle. On the presentation of other components, such as the formation of the bottom of the bottle, was omitted for reasons of clarity. The reference numeral 4 shows a longitudinal axis of the exchange insert 1 and the blow mold second

The blow mold 2 has an edge region 13, on which the locking mechanism according to the invention to be described below is arranged. Recesses 14 are formed on side regions of the interchangeable insert 1, by means of which clamping surfaces 15 are formed, against which clamping pieces 3 to be described below can be applied.

At the edge region 13, a bridge 8 is mounted according to the invention. This has fastening holes 16 through which screws, not shown, are feasible to firmly connect the bridge 8 with the blow mold 2.

As can be seen in particular from the perspective view of FIG. 3, the bridge 8 has a U-shaped cross-section and forms an interior in which a slide 5 extending in the longitudinal direction of the bridge 5 is received in a longitudinally displaceable manner. The bridge 8 further wäest pocket-like recesses 7, in which the subsequently described to be described clamping pieces 3 and transversely to the longitudinal direction of the bridge 8 are displaced. The pocket-like recess 17 is in each case provided with a conical contact surface 12, as will be described below. The bridge 8 furthermore has an eccentric recess 18, in which an eccentric element 9, which is provided with tool engagement means 10 (hexagonal recess or the like), is rotatably arranged. Analogously, the slide 5 has an eccentric recess 19, in which the other part of the eccentric element 9 is received and guided. By a rotation of the eccentric 9 thus takes place a longitudinal displacement of the slider 5 relative to the bridge 8 and to the blow mold 2. As is apparent in particular from the illustration of FIG. 4, the slide 5 sliding elements in the form of grooves 6, which are arranged at an angle to the longitudinal axis of the slider 5. The angle is for example 45 °. Matching the grooves 6, the clamping pieces 3 are provided with rib-shaped sliding elements 7. These ribs 7 are accurately mounted in the respective groove 6. By a longitudinal displacement of the slider 5 thus takes place a transverse movement of the clamping pieces 3. It is thus a positive coupling in the form of a slide guide before.

5 to 8 each show sectional views, partly in detail, perpendicular to the longitudinal axis 4, wherein in FIGS. 5 to 8 each show a closed position or locking position. Fig. 5 shows the eccentric 9 in the locked position. It can be seen that the clamping pieces 3 each have a conical or chamfered cross-section (conical cross-sectional area 11) which abuts against the conical contact surface 12 of the bridge 8. Thus, a clamping of the clamping pieces 3, in order to apply a clamping force on the removable insert 1 can.

By a rotation of the eccentric 9 and a displacement of the slider 5 caused thereby, the clamping pieces 3 are brought from the locking position shown in FIGS. 5 to 8 in the release position shown in FIGS. 9 to 12 or opened position. In this position, the clamping pieces 3 a game on the conical cross-sectional area 11 and have been forcibly withdrawn into the interior of the recess of the bridge 8 by the interaction of the groove 6 with the rib 7. The invention is not limited to the embodiment shown. Rather, arise in particular with regard to the Vorspannmöglichkeit the clamping pieces 3 and the design of the slider 5 and the bridge 8 and the operation of the slide 5 different Abwandlungs- and modification options.

LIST OF REFERENCES

1 change insert

2 blow mold

3 clamping piece

4 longitudinal axis

5 slides

6 groove

7 rib

8 bridge

9 eccentric element

10 tool interventions

11 conical cross-sectional area

12 conical contact surface

13 border area

14 recess

15 clamping surface

16 mounting hole

17 recess

18 eccentric recess

19 eccentric recess

Claims

claims

A multi-part blow mold for the production of blown, made of plastic workpieces, with at least one locking mechanism for releasably locking a removable insert (1) in a blow mold (2), wherein the

Locking mechanism comprises a plurality of clamping pieces (3) which are displaceable transversely to a longitudinal axis (4) of the exchange insert (1) between a release position and a locking position, characterized in that the clamping pieces (3) for their displacement with one along the longitudinal axis (4) the removable insert (1) movable and mounted on the blow mold (2)

Slider (5) are coupled.

2. blow mold according to claim 1, characterized in that the clamping pieces (3) by means of a sliding guide with the slider (5) are coupled.

3. Blow mold according to claim 2, characterized in that the slotted guide sliding elements (6, 7) which are arranged at an angle to the direction of displacement of the clamping pieces (3) and the direction of movement of the slide (5).

4. Blow mold according to one of claims 1 to 3, characterized in that the slide (5) is mounted on a fixed to the blow mold bridge (8).

5. Blow mold according to one of claims 1 to 4, characterized in that the slide (5) by means of an eccentric element (9) is movable, which is provided with tool engagement means (10).

6. Blow mold according to one of claims 1 to 5, characterized in that the clamping piece (3) has a conical cross-sectional area (11).

7. blow mold according to claim 6, characterized in that the bridge (8) is provided at least in the region of the clamping pieces (3) with a conical contact surface (12). Blow mold according to one of claims 5 to 7, characterized in that the eccentric element (9) is positively lockable in the bridge (8) drehsicherbar.