EP0724530B1

EP0724530B1 - Container of thermoformable material with a closing lid integral therewith

Info

Publication number: EP0724530B1
Application number: EP94931552A
Authority: EP
Inventors: Pietro Padovani
Original assignee: Isap OMV Group SpA
Current assignee: Isap OMV Group SpA
Priority date: 1993-10-29
Filing date: 1994-10-26
Publication date: 1997-12-10
Anticipated expiration: 2014-10-26
Also published as: WO1995011834A1; ES2109738T3; IT231600Y1; EP0724530A1; ITVR930043V0; AU8060294A; DE69407307D1; DE69407307T2; ITVR930043U1; ATE160994T1

Abstract

A container of thermoformable material equipped with a closing lid integral therewith comprises a hollow container body (2), a lid (3) and a hinge portion or strip (4) which is integral with the container body (2) on the one side and the lid (3) on the other. The said container has guide means (13) for the lid (3) provided on the container body (2) which slidably engage one edge (15) of the lid (3) close to the said hinge portion or strip (4) when the lid (3) is closed.

Description

This invention relates to a container of thermoformable material with a closing lid integral therewith, which is particularly indicated for the packaging of food produce such as fruit, vegetables and the like.
A container of thermoformable material having a container body connected to a lid by means of a connecting portion or strip in which two longitudinal recesses acting as a double fold or hinge line are made by thermoforming so that the lid can be placed in a closed position above the container merely by folding over the lid has already been disclosed e.g. in GB- PS 2 195 318 (ISAP S.p.a.). Both the lid and the container are equipped with press-stud retaining means to hold the lid in the closed position.
In FR-A-2546855 there is disclosed a container of thermoformable material equipped with a closing lid integral therewith which incorporates a hollow container body, a lid and a hinge portion or strip integral with the body on one side and the lid on the other side, guide means being provided on the body to slidably engage one edge of the lid close to the hinge portion or strip when the container is closed.
In automatic packaging plants, once the container has been filled the lid is generally caused to close by means of a mechanical arm. It may however, happen that because of the rigidity of the material of which the interconnecting strip between the container and the lid is made and the inevitable asymmetrical thrust forces applied by the arm to the lid as it closes, the lid is caused to follow an incorrect or crooked closure trajectory with respect to the container body, which may result in defective closure and in some cases failure of the lid to engage with the retention means provided on the container. When this circumstance arises an operator must take action, resulting in additional costs and even a slowing in the operating speed of the packaging plant with a consequent fall in productivity.
The principal object of this invention is to eliminate or drastically reduce the above-mentioned inconvenience by providing a container with a lid integral therewith which is constructed in such a say as to ensure perfect mating of the lid with the container during the closure stage at all times.
Another object of this invention is to provide a container of the above-mentioned type which is equipped with great structural stability, which can be stacked stably when filled with produce and which can be manufactured at a competitive cost.
According to the present invention there is provided a container of thermoformable material having a closing lid integral therewith, which comprises a hollow container body, the lid arranged to be brought either in a closed position on the container body and to be retained thereon, or to an open position by being turned up, a flexible hinge portion or strip which is integral with the near edge of both the container body and the lid, guide means for the lid while being closed, and designed to releasably engage the lid to the container body when in the closed position, said guide means comprising at least two tapering projections emerging, respectively, from the container body and the lid and said hinge portion or strip having a pair of parallel recesses acting as lines of weakness, characterised in that the tapering projections on the lid are arranged to slidably engage in the form of inclined planes with respective projection(s) on the container body to prevent both excessive forward displacement and lateral displacements of the lid while being moved to its closed position, and in that said pair of parallel recesses have a trough configuration so as to taper out at the ends of said hinged portion or strip.
The invention is further described below with reference to the appended drawings, in which:

Figure 1 is a side view in elevation of a container with a lid in a completely open position folded back by 180° with respect to the container body,
Figure 2 illustrates a plan view of the container in Figure 1,
Figure 3 shows a detail of Figure 2 on a magnified scale,
Figures 4 to 7 are each side views in elevation of the container in Figures 1 and 2 with the lid positioned at various angles of partial closure and in the completely closed position,
Figure 8 is a side view in elevation of a variant of the container according to the invention,
Figure 9 illustrates a plan view of the container in Figure 8,
Figure 10 illustrates a cross-sectional view along the line X-X in Figure 9,
Figure 11 is a side view in elevation of another variant of the container according to the invention, and
Figure 12 illustrates a plan view of the container in Figure 11.

In the appended drawings identical or similar parts or components are identified by means of the same reference numbers.
With reference first to container 1 illustrated in Figures 1 to 7, it will be noted that this comprises a container body 2, a lid 3 and a hinge portion or strip 4 which is integral with the rear upper edge 5 of the container body on one side and with the rear edge 6 of the lid on the other.
Container body 2 and lid 3 (which is preferably slightly box-shaped) are substantially rectangular in plan with their two corresponding rear corners rounded and the front corners trimmed, indicated by 7 on the container body and 8 on the lid. Each trimmed portion 7 and 8 forms a relatively rigid section of wall on the front of which is provided a portion of male and female retaining means. Typically trimmed corners 7 of the container body have a female connection 9, preferably with an undercut edge, which is designed to engage releasably with a corresponding projection 10 in the lid to form "press-stud" retaining means.
Both the container body and the lid have outwardly projecting ribs 11 and 12 in both the base part and the side walls. Ribs 11 and 12 extend partly (for example those indicated by 11) in planes parallel to one direction, e.g. the front to back direction, and partly (those indicated by 12) in parallel planes in a direction perpendicular to the former. Also the ribs provided in container body 2 are slightly offset with respect to those provided in lid 3 so that when packed containers 1 are closed they stack together, and the fact that the various ribs of the lid of the container beneath engage the corresponding offset ribs in the container body of the container above prevents mutual displacements between the containers in the stack or pile.
At the rear rounded edges of container body 2 there is provided a corresponding arched top projection 13 which follows the curvature of the corner and corresponds to the lower edge of the container body and extends partly along the edge of the side wall adjacent to it. Preferably each projection 13 has a rearward-facing back or surface configured substantially as an inclined plane (Figure 3).
Correspondingly cover 3 has an arched projection 15 at its own rear rounded corners which follows the curvature of the corresponding corner and extends either along the rear edge of the lid or along the side wall adjacent to it, but with a radius of curvature which is slightly greater than that of the corresponding projection 13 on the container body.
Advantageously internal wall 16 of each projection 15 is inclined to complement the inclination of the corresponding flat inclined wall of adjacent projection 13.
With this arrangement and construction of the parts and components of the container, once lid 3 approaches the container body at a predetermined angle, e.g. approximately 60°, Figure 5, as it is closed, its projections 15 begin to abut against and slidably engage corresponding projections 13 on the container body and ensure a guided rotational movement of the lid towards the container, preventing both uncontrolled forward displacements and lateral displacements of the lid. In this way lid 3 is guided safely to engage accurately with the container body (Figure 7) and in particular projections 10 are inserted accurately into the corresponding receiving seat 9 provided in the container body, as clearly shown in the operating sequence illustrated in Figures 5 to 7.
To allow correct bending of hinge portion or strip 4 the latter incorporates two substantially trough- shaped recesses 17 and 18, which constitute lines of weakness and preferential folding for a correct approach by the lid to the container body as it closes. Recesses 17 and 18 are of decreasing depth towards their ends so that they finally become flush with the plane of strip 4, as illustrated in Figure 3.
In the variant embodiment illustrated in Figures 8 to 10, hinge portion or strip 4 has an intermediate opening 20 which is used to lighten hinge strip 4 in order to make it yield and fold more easily. This arrangement is particularly advantageous when relatively rigid materials are used to construct the container or if portion 4 has a substantial thickness.
Figure 10 in particular shows the trough configuration of a recess 17 which is bevelled down to the plane of portion 4.
Figures 11 and 12 illustrate a variant in which projections 13 and 15 are replaced by lateral projections, 13a and 15a respectively, and by rear projections, 13b and 15b respectively. Projections 13a are designed to be slidably engaged by a corresponding projection 15a to guide the lid when it closes so as to prevent lateral slippage thereof, while projections 13b act as engaging members for corresponding projections 15a to ensure that the lid does not advance excessively, but are also guided in a front to rear direction so that they ensure that projections 10 are centred sufficiently accurately on the corresponding receiving seats 9 in the container body.
As may be seen, a container having the features described above is capable of effectively accomplishing all the objects specified at the start of this description both in respect of the accuracy of the mating between the lid and the container body during closure and as regards the simplicity of its structure.
A container according to this invention allows modifications and variants within the scope of the protection defined by the contents of the following claims.
Materials and dimensions may vary according to requirements.

Claims

A container (1) of thermoformable material having a closing lid (3) integral therewith, which comprises a hollow container body (2), the lid (3) arranged to be brought either in a closed position on the container body (2) and to be retained thereon, or to an open position by being turned up, a flexible hinge portion or strip (4) which is integral with the near edge of both the container body (2) and the lid (3), guide means (13, 15) for the lid (3) while being closed, and designed to releasably engage the lid (3) to the container body (12) when in the closed position, said guide means comprising at least two tapering projections (13, 15) emerging, respectively, from the container body (2) and the lid (3) and said hinge portion or strip (4) having a pair of parallel recesses (17, 18) acting as lines of weakness, characterised in that the tapering projections (13, 15) on the lid (3) are arranged to slidably engage in the form of inclined planes with respective projection(s) on the container body (2) to prevent both excessive forward displacement and lateral displacements of the lid (3) while being moved to its closed position, and in that said pair of parallel recesses (17, 18) have a trough configuration so as to taper out at the ends of said hinged portion or strip (4).
A container as claimed in claim 1, characterised in that the said hinge portion or strip (4) has at least one weakening opening or window (20).
A container as claimed in claim 1 or 2, characterised in that both the container body (2) and the lid (3) have outwardly projecting ribs (11,12) in both the base part and the side walls thereof, part of the ribs(11,12) extending in planes parallel to one direction and part of them in planes at right angles thereto.
A container as claimed in claim 3, characterised in that the ribs on the container body (2) are slightly offset with respect to those on the lid (3), thereby preventing mutual displacements between closed containers (1) in a stock or pile.