EP3802055A1

EP3802055A1 - Grip device for containers

Info

Publication number: EP3802055A1
Application number: EP19731346.3A
Authority: EP
Inventors: Nicola ANDREATTA; Arnaldo BERTUOL
Original assignee: Sacmi Imola SC
Current assignee: Sacmi Imola SC
Priority date: 2018-05-29
Filing date: 2019-05-23
Publication date: 2021-04-14
Also published as: WO2019229595A1; CA3101779A1; IT201800005793A1

Abstract

A grip device (1) for containers, in particular for preforms (10) of plastic containers, which comprises at least one elongated body (2) which has, at a first end (2a), a supporting body (3) and, at the opposite end, a radially expandable element (4) in order to pass, on command, between a retracted condition which is adapted to allow the insertion and the withdrawal of at least one portion of the elongated body (2) into or out of a cavity (10a) which is defined in a respective container (10), and an expanded condition in which the expandable element (4) is engaged against the inner surface of the cavity so as to allow the gripping and the movement of the respective container (10); the expandable element (4) has a plurality of longitudinal elements (5) which are arranged around an axis of extension and of movement (100) and are provided in a single piece with the supporting body (3); the grip device (1) comprises an actuation body (20) which is arranged internally with respect to the expandable element (4) and can move, on command, longitudinally in order to engage with an inner coupling surface (6) which is defined on the longitudinal elements (5) in order to cause their radial expansion, the longitudinal elements (5) being elastically radially expandable and retractable in order to autonomously return to the retracted condition.

Description

GRIP DEVICE FOR CONTAINERS

The present invention relates to a grip device for containers such as the preforms and, in particular, for extracting preforms from the cooling plates of injection molding presses.

Picking up preforms from the cooling plates of injection molding presses is nowadays substantially done in two ways.

A first type of gripping devices comprises nozzles that create a vacuum inside the preform body, while applying a seal on the upper rim.

A second type involves the use of grippers which, by expanding, apply a grip at the inner surface of the neck of the preform.

Such solution optionally also makes it possible to create an overpressure inside the preform, such as for example disclosed in US7887320.

Both solutions described briefly above have a number of drawbacks. With reference to the solution with nozzles, it should be noted that this may result in an ineffective grip if there are defects in the neck of the preform.

Such solution further causes a higher energy consumption than in other solutions, both if a vacuum pump is used, and if systems based on the Venturi effect are used.

Furthermore, if some cavities of the mold are closed off, the respective nozzle must be stoppered in order not to nullify the operation of all the others.

Finally, it should be noted that such solution makes it possible to obtain, on average, a lesser force to hold the preform.

Considering the solution that uses the gripper, it should be noted that the dimensions of the latter depend on the dimensions of the neck, with the consequent need to change the gripper as the dimensions of the preform vary.

A grip element made of rubber is further subject to wear and can leave traces of rubber inside the preform.

Furthermore, such solution is mechanically rather complex, since the grippers are, effectively, pistons made up of ten or so different parts.

Lastly, there is a certain difficulty of disassembly in the event of breakage, or during the operations to change the elastic elements, an intervention that is usually necessary after 6-9 months of continuous operation.

The aim of the present invention is to provide a grip device for containers which is capable of improving the known art in one or more of the above mentioned aspects.

Within this aim, an object of the invention is to reduce the maintenance and changes of the elastic elements.

Another object of the invention is to provide a grip device that is highly reliable, easy to implement and of low cost.

This aim and these and other objects which will become better apparent hereinafter are achieved by a grip device according to claim 1, optionally provided with one or more of the characteristics of the dependent claims.

Further characteristics and advantages of the invention will become better apparent from the detailed description that follows of a preferred, but not exclusive, embodiment of the grip device according to the invention, which is illustrated for the purposes of non-limiting example in the accompanying drawings wherein:

Figure 1 is a perspective view of the grip device according to the invention;

Figure 2 is a longitudinally cross-sectional perspective view of the grip device;

Figure 3 is a longitudinal cross-sectional view of the grip device with the expandable element in the expanded condition.

With reference to the figures, the grip device for containers according to the invention, generally designated by the reference numeral 1, comprises, in particular, a grip device 1 for preforms 10 of plastic containers.

The grip device 1 comprises at least one elongated body 2 which has, at a first end 2a, a supporting body 3 and, at the opposite end 2b, a radially expandable element 4 in order to pass, on command, between a retracted condition which is adapted to allow the insertion and the withdrawal of at least one portion of the elongated body 2 into or out of a cavity 10a which is defined in a respective container 10, and an expanded condition in which the expandable element 4 is engaged against the inner surface of the cavity 10a so as to allow the gripping and the movement of the respective container 10.

According to the present invention, the expandable element 4 has a plurality of longitudinal elements 5 which are arranged about an axis of extension and of movement 100.

The longitudinal elements 5 are provided in a single piece with the supporting body 3.

In this regard, the longitudinal elements 5 can be welded or locked mechanically to the supporting body 3 in order to provide a single body.

The grip device 1 further comprises an actuation body 20, which is arranged internally with respect to the expandable element 4.

The actuation body 20 can move, on command, longitudinally, i.e. parallel to the axis of extension and of movement 100, in order to engage with an inner coupling surface 6 which is defined on the longitudinal elements 5.

The movement of the actuation body 20 causes the expansion in a radial direction of the longitudinal elements 5, which are elastically radially expandable and retractable in order to autonomously return to the retracted condition.

Conveniently, the longitudinal elements 5 have a connecting portion 5a for connecting to the supporting body 2 and a contact portion 5b which is intended to come into contact, in the expanded condition, with the inner surface of a respective cavity 10a.

Conveniently the longitudinal elements 5 extend, transversely, along a respective circular arc around the axis of extension and of movement 100.

Advantageously, the connecting portion 5a has a transverse extension that is shorter with respect to the contact portion 5b.

Such implementation choice makes it possible to optimize the radial elasticity of the longitudinal elements 5, thus providing for a more evenly - applied stress.

Preferably, but not necessarily, the contact portion 5b is cask-shaped.

Such cask shape of the contact portion 5b makes it possible to have a grip zone even if the diameter of the cavity 10a varies.

The inner coupling surface 6 comprises, conveniently, an inclined lip 7 which is connected, at a connection section, with the surface directed toward the inside of the contact portion.

In particular, the lip is elastically yielding in a radial direction with respect to the respective contact portion when a predetermined stress is exceeded.

This makes it possible to absorb any excessive stresses while avoiding possible overloads between the contact portion 5b and the cavity 10a which could damage the preform 10 in some way.

According to a preferred embodiment, the actuation body 20 is adapted to engage with the inner coupling surface 6 in order to produce the transition of the expandable element 4 from the retracted condition to the extended condition following a pushing movement in the direction of the second end 2b.

The gripping devices 1 can be associated with a chain or a strap for support and movement, with a plate for movement and/or extraction, etc. .

Use of the grip device 1, according to the invention, is evident from the foregoing description.

In practice it has been found that the invention fully achieves the intended aim and objects.

The invention, thus conceived, is susceptible of numerous modifications and variations, all of which are within the scope of the appended claims. Moreover, all the details may be substituted by other, technically equivalent elements.

In practice the materials employed, provided they are compatible with the specific use, and the contingent dimensions and shapes, may be any according to requirements and to the state of the art.

The disclosures in Italian Patent Application No. 102018000005793 from which this application claims priority are incorporated herein by reference.

Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly, such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.

Claims

1. A grip device (1) for containers, in particular for preforms (10) of plastic containers, which comprises at least one elongated body (2) which has, at a first end (2a), a supporting body (3) and, at the opposite end, a radially expandable element (4) in order to pass, on command, between a retracted condition which is adapted to allow the insertion and the withdrawal of at least one portion of said elongated body (2) into or out of a cavity (10a) which is defined in a respective container (10), and an expanded condition in which said expandable element (4) is engaged against the inner surface of said cavity so as to allow the gripping and the movement of the respective container (10), characterized in that said expandable element (4) has a plurality of longitudinal elements (5) which are arranged around an axis of extension and of movement (100) and are provided in a single piece with said supporting body (3), said grip device (1) comprising an actuation body (20) which is arranged internally with respect to said expandable element (4) and can move, on command, longitudinally in order to engage with an inner coupling surface (6) which is defined on said longitudinal elements (5) in order to cause their radial expansion, said longitudinal elements (5) being elastically radially expandable and retractable in order to autonomously return to the retracted condition.

2. The grip device (1) according to claim 1, characterized in that said longitudinal elements (5) have a connecting portion (5a) for connecting to said supporting body and a contact portion which is intended to come into contact, in the expanded condition, with the inner surface of a respective cavity.

3. The grip device (1) according to one or more of the preceding claims, characterized in that said longitudinal elements extend, transversely, along a respective circular arc around the longitudinal axis of said elongated body.

4. The grip device (1) according to one or more of the preceding claims, characterized in that said connecting portion has a transverse extension that is shorter with respect to said contact portion.

5. The grip device (1) according to one or more of the preceding claims, characterized in that said contact portion is cask-shaped.

6. The grip device (1) according to one or more of the preceding claims, characterized in that said inner coupling surface (6) comprises an inclined lip which is connected, at a connection section, with the surface directed toward the inside of said contact portion.

7. The grip device (1) according to one or more of the preceding claims, characterized in that said lip is elastically yielding in a radial direction with respect to the respective contact portion when a predetermined stress is exceeded.

8. The grip device (1) according to one or more of the preceding claims, characterized in that said actuation body is adapted to engage with said inner coupling surface in order to produce the passage of said expandable element from said retracted condition to said extended condition following a pushing movement in the direction of said second end.