FR2736329A1 - CAPPING CAPE PROVIDED WITH A DEGASSING DEVICE, METHOD FOR MANUFACTURING SUCH A CAPE AND DEVICE FOR CARRYING OUT SAID METHOD - Google Patents

Abstract

A venting closure (1) with a hinged cover (5) has a degassing device provided by a chimney (8) which extends inwardly from the end (3) of the body (2) of the cap. At its inner end the chimney is closed by an inclined semi-permeable membrane (9), whereas the outer end of the chimney, in the plane of the cap end (3), is permanently closed by a hinged lid (10) formed with vent holes (11). The lid (10) is moulded in one-piece with the cap. It is moulded open, and is closed in the mould at the same time as the cover is closed. For that purpose the cover has an inwardly extending rib (13) which engages it as the cover closes. The mould also has provision for cutting the membrane (9) from a parent strip, and for positioning it in the mould cavity prior to the injection of synthetic material.

Description

 An object of the present invention is a closure cap provided with a degassing device.

 Such a cap comprises a tubular body intended to cooperate with the neck of a container, a bottom provided with an opening allowing the product contained in the container to exit from the latter and a cap articulated on the body comprising cooperating plugging means. with the opening made in the bottom of the cape.

 It is known to provide such a cap with a degassing device. The latter can be a valve which mechanically lets the gases trapped inside the container pass when a certain overpressure prevails inside the latter.

 There are also degassing devices comprising a membrane. The latter is permeable to gases, but impermeable to liquids. A second opening is then provided in the bottom of the cape.

The semi-permeable membrane separates this second opening from the interior of the container. Generally, this membrane is protected from the outside in that the second opening is of reduced size or in that this second opening consists of a plurality of small holes.

 The invention also relates to a method for manufacturing a closure cap provided with a degassing device, as well as a device for implementing this method.

 The main drawback of known closure caps provided with a degassing device and known methods for manufacturing these caps is that it is necessary to attach the degassing device to a cap in order to produce the final product. Therefore, the sealing cap is manufactured on one side and the degassing device on the other side and the two sub-assemblies are assembled to form the final product.

 All these operations increase the cost price of a closure cap provided with a degassing device. Indeed two injection molds and two injection stages, one for the cap and the other for the degassing device, as well as numerous manipulations of the intermediate parts are necessary.

 The object of the invention is therefore to propose a new sealing cap incorporating a degassing device, as well as a method of manufacturing such a cap and a device for implementing this method, so that the device of degassing is integrated into the closure cap and forms therewith only one assembly.

 To this end, the closure cap which it offers is made of synthetic material and comprises a tubular body intended to cooperate with a neck of a container, a bottom provided with an opening allowing the product contained in the container to exit from this last and a cap articulated on the body and comprising plugging means cooperating with the opening made in the bottom.

According to the invention, the bottom has
- a chimney extending with respect to the bottom on the same side as the body and closed by a semi-permeable membrane, impermeable to liquids and permeable to gases,
a cover hinged in the plane of the bottom on one edge of the chimney and having at least one passage allowing gases to escape, and
means ensuring that the cover is kept in the closed position, and
the cap has, on the side facing the bottom, a rib intended to cooperate with the cover to close the latter when the cap is closed for the first time.

 This closure cap therefore includes a degassing device integrated into the bottom of the closure cap. When the cap is closed, liquid contained in the container cannot flow, because the opening allowing the exit of the liquid is blocked and the membrane closing the chimney is impermeable to liquids. However, the gases present in the container can escape by first passing through the membrane, then by evacuating through the chimney and the passage provided in the cover.

 In an advantageous embodiment, allowing a good closing of the cover, the base of the chimney placed in the plane of the bottom of the cape is in the shape of a semicircle, oriented so that the rectilinear part of this base is located from the side of the joint between the bottom and the cap and is substantially parallel to this joint, and the cover is articulated on the straight edge of the chimney.

 Preferably, the cover is kept in the closed position on the bottom of the cape by an irreversible snap-fastening. This ensures that the cover remains closed after its first closure.

The invention also provides a method for manufacturing a cape such as that described above. This process includes the following steps
- cutting of a membrane in a strip of semipermeable material,
- placement of the cut membrane in a mold, so that the membrane rests against a wall of the mold1
- closing the mold,
- injection of synthetic material, with imprisonment of the periphery of the membrane,
- opening of the mold after cooling of the injected material,
closing of the cap of the cap thus molded, and simultaneously closing of the cover, and
- ejection from the mold.

 Advantageously, a part of the mold comprises a central core, which forms the tool used for cutting the strip of semi-permeable material, axially displaceable, which crosses the joint plane of the mold, then moves in the opposite direction, carrying with him the cut membrane, until the latter occupies its place in the mold, the central core then constituting an integral part of the mold during the injection of synthetic material.

 This procedure avoids many manipulations of the membrane to perform its cutting and its transfer into the mold. Here, only one manipulation is necessary.

 The invention finally proposes a device for implementing this method.

 This device is of the type comprising a mold in at least two parts, a synthetic material injection device, a device for closing the cap of the closure cap and a device for ejecting the part from the mold.

 According to the invention, it further comprises a device for passing a strip of semi-permeable synthetic material and a tool for cutting the membrane.

 To be faster and avoid manipulation during the cutting and transfer of the membrane, a part of the mold has a central core which forms the membrane cutting tool, movable axially perpendicular to the joint plane of the mold, at the level from the place provided to form the chimney of the closure cap carrying the membrane. In addition, this central core includes a device for retaining the cut membrane, and serves as a mold wall supporting the membrane during the injection of synthetic material.

 Finally, advantageously, the device for closing the cap of the closure cap and the device for passing the strip of semi-permeable material are mounted on the same support.

 In any case, the invention will be clearly understood with the aid of the description which follows, with reference to the appended schematic drawing representing a closure cap according to the invention, a device making it possible to manufacture such a closure cap, this drawing illustrating also a method of manufacturing such a cape.

FIG. 1 is a sectional view of a closure cap before it is closed for the first time,
FIG. 2 is a view similar to the view in the preceding figure, the closure cap being closed,
Figure 3 is a top view of Figure 1,
FIG. 4 shows in section, on a reduced scale, a part of the mold for producing a closure cap as shown in the preceding figures,
FIG. 5 is a sectional view, on an enlarged scale with respect to FIG. 4, of this part of the mold in the closed position, and
Figure 6 shows a sealing cap before leaving the mold.

 A closure cap 1 is shown in FIGS. 1 and 2.

It is intended to close a container (not shown). In known manner, it comprises a tubular body 2, a bottom 3, an opening 4 and a cap articulated on the body 2.

 The tubular body 2 is of generally circular cylindrical shape. It has an internal thread 6 on its internal wall, so that it can be screwed onto the neck of the container for which it is intended.

 The bottom 3 has a first opening 4 through which the product contained in the container can exit. It can, for example, be a cleaning product. This opening 4 is placed near the edge of the bottom 3, near the body 2, on the side opposite the articulation between the body 2 and the cap 5.

 A second opening 7 is made in the bottom 3. It forms the base of a chimney 8 extending perpendicular to the bottom 3, on the same side of the latter as the body 2. This opening 7 is in the shape of a semicircle , the rectilinear part of this semicircle being on the side of the articulation between the body 2 and the cap 5 and being parallel to this articulation (Figure 3).

 The chimney 8 is closed at its end opposite to the opening 7 by a semi-permeable membrane 9 fixed to the wall of the chimney. The membrane 9 is located in an inclined plane relative to the bottom 3.

 The membrane 9 is made of a material permeable to gases, but impermeable to liquids, in particular to liquids intended to fill the container on which the closure cap 1 is mounted. Such materials are known and are within the reach of ordinary skill in the art. job.

 On the edge of the second opening 7, at the base of the chimney 8, on the side of the articulation between the body 2 and the cap 5, is a cover 10 mounted in an articulated manner by a film hinge. This cover 10 is placed on the rectilinear side of the opening 7. Its edge opposite its articulation is slightly inclined, as is the corresponding edge of the opening 7, so that this cover can snap onto the bottom 3.

 Notches 11 of small section are provided in the cover 10 to allow the gases initially contained in the container to escape and which pass through the membrane 9.

 The cap 5 comprises, in a manner known per se, a stud 12 cooperating with the first opening 4 in order to close the latter in leaktight manner when the cap 3 is closed (FIG. 2).

 The cap 5 also includes a rectilinear rib 13.

The latter is, like the stud 12, placed on the face of the cap located on the side of the bottom 3 in the closed position. This rib 13 is placed so that by closing the cap 5, the rib 13 drives the cover 10 in its movement and closes it. The cover 10 snaps onto the bottom 3 and remains closed. It is therefore permanently closed by the rib 13 when the cap 5 is closed for the first time.

 FIG. 5 represents a device for manufacturing a closure cap, such as that shown in FIGS. 1 and 2. This device comprises a lower part of the mold 50, an upper part of the mold 51, a device for the injection of synthetic material 52 used to manufacture the closure cap 1, a device 53 for passing a strip 54 of material to form the membrane 9, as well as a device 56 for closing the cap 5 of the cap 1.

 The lower part of the mold 50 is equipped with a device making it possible to release the plugging cap 1 once molded out of the mold (50, 51). This part of the mold 50 is provided with a thread 57 of shape complementary to the internal thread 6 of the closure cap. This thread 57 is produced on a cylindrical tubular core 58 which can be rotated by a device not shown in the drawing and not described here, because such a device is known to those skilled in the art. Once the part is molded, the tubular core 58 is unscrewed and the part can then be ejected.

 The lower part of the mold 50 can move in translation to approach or move away from the upper part 51 which is fixed. The device for injecting synthetic material 52 is connected to the upper part of the mold 51.

 The scrolling device 53 and the closing device 56 of the cap are mounted on the same support 59, integral with the lower part 50 of the mold. These two devices 53, 56 are placed between the lower 50 and upper 51 parts of the mold when these are distant from one another.

 The lower part of the mold 50 has a central core 55 which can be moved axially. This central core 55 can cross the joint plane of the mold. The end of this central core 55 is shaped as a cutting tool for cutting the strip 54 running on the device 53. This central core 55 is also coupled to a vacuum pump (not shown) by a channel 60 so as to be able to maintain the cut membrane 9 and transfer it to the lower part 50 of the mold. The mechanism allowing the displacement of the core 55 has not been shown in the drawing. The end of the core 55 is also designed to serve as a mold wall and a membrane support 9 during the injection of synthetic material into the mold.

 The manufacturing method according to the invention of a closure cap 1, such as for example that shown in FIGS. 1 and 2 is described below with reference to FIGS. 4 to 6.

 In Figure 4, the mold is open. The scrolling device 53 is placed between the two parts 50, 51 of the mold, so that the strip 54 is located in the axis of the core 55. The mold is empty.

 The central core 55 moves first of all towards the strip 54 and cuts the latter to form the membrane 9. Thanks to the channel 60 connected to a vacuum pump, the membrane 9 is held at the end of the core 55. This the latter regains the position drawn in solid lines in FIGS. 4 to 6 to serve as a support for the cut membrane 9 and to constitute an integral part of the wall of the lower mold 50.

 After removal of the scrolling device 53 from the strip 54, the lower part of the mold 50 rises and joins the upper part 51 of the mold in order to close the latter. Synthetic material is injected. It may for example be a polyethylene or a polypropylene. Note in Figure 5 that the upper part of the mold 51 is provided so that the membrane 9 is not covered with injected material. Only the edge of this membrane is covered. The temperature of the injected material is sufficient to thus ensure the bonding of the membrane 9 to the chimney 8.

It can also be seen (FIG. 5) that the cover 10 is molded in the open position.

 When the injection is complete and the injected material has cooled, the mold is opened. The support 59, mounted on the lower part of the mold 50 advances towards the space left free between the two parts 50, 51 of the mold. The tubular core 58 carrying the thread 57 is rotated to release the sealing cap 1. The cap 5 comes out of the lower part 50 of the mold.

 Once the cap 5 has left the mold, the closing device 56 comes to close it. This device 56 is mounted on the support 59 by means of a jack 61 (FIG. 4). The head of this device is fitted with a roller 62.

 The mold, and in particular its lower part 50, and the closure device 56 of the cap are placed relative to each other so that, when the jack 61 moves the closure device 56 towards the closure cap 1 , the caster 62 first meets the cap 5.

Continuing its course, the device 56 closes the cap 5 and, thanks to the roller 62, no scratching is likely to be made.

 During the closing of the cap 5, the rectilinear rib 13 placed inside of it comes to meet the cover 10. This rib 13 is shaped so that, when the cap 5 is fully closed, the cover 10 is snapped onto the bottom 3 of the sealing cap 1.

 This device and this method therefore make it possible, as shown above, to produce a closure cap 1 provided with a degassing device by making only one injection and without assembly operation requiring numerous manipulations.

 It goes without saying that the invention is not limited to the sealing cap, nor to the process for manufacturing the same, nor to the device for implementing this process, described above by way of examples. not limiting; on the contrary, it embraces all its variants.

 Thus, for example, the notches made in the cover can be replaced by one or more holes. The rectilinear rib can be replaced by a curved, semi-circular or even circular rib. The shape of the chimney can be quite different and present for example a circular or polygonal section.

Claims (8)

 1. Clogging cap made of synthetic material provided with a degassing device comprising a tubular body (2) intended to cooperate with a neck of a container, a bottom (3) provided with an opening (4) allowing the product contained in the container to come out of the latter and a cap (5) articulated on the body (2) and comprising closure means (12) cooperating with the opening (4) made in the bottom (3), characterized in that the bottom (3) presents  - a chimney (8) extending, relative to the bottom (3), on the same side as the body (2) and closed by a membrane (9) semipermeable, impermeable to liquids and permeable to gases,  - a hinged cover (10) in the plane of the bottom on one edge of the chimney (8) and having at least one passage allowing gases to escape, and  - means ensuring that the cover (10) is kept in the closed position,  and in that the cap (5) has, on the side facing the bottom (3), a rib (13) intended to cooperate with the cover (10) to close the latter during the first closure of the cap (5) .  2. Clogging cap according to claim 1, characterized in that the base of the chimney (8) placed in the plane of the bottom (3) of the cap is in the shape of a semicircle, oriented so that the rectilinear part of this base is located on the side of the joint between the bottom (3) and the cap (5) and is substantially parallel to this joint, and in that the cover (10) is articulated on the straight edge of the chimney.  3. Clogging cap according to claim 1 or 2, characterized in that the cover (10) is held in the closed position on the bottom (3) of the cap by an irreversible snap-fastening.  4. Method for manufacturing a closure cap (1) according to one of claims 1 to 3, characterized in that it comprises the following steps  - cutting a membrane (9) in a strip (54) of semi-permeable material,  - placement of the membrane (9) cut from a mold (50, 51), so that the membrane rests against a wall of the mold,  - closing the mold,  - injection of synthetic material, with trapping of the periphery of the membrane (9),  - opening of the mold after cooling of the injected material,  closing of the cap (5) of the cap (1) thus molded, and simultaneously closing of the cover (10), and  - ejection from the mold.  5. Method according to claim 4, characterized in that a part of the mold (50) comprises a central core (55), which forms the tool used for cutting the strip of semi-permeable material (54), movable axially, which crosses the joint plane of the mold, then moves in the opposite direction, taking with it the cut membrane (9), until the latter occupies its place in the mold, the central core (55) then constituting an integral part of the mold during the injection of synthetic material.  6. Device for implementing the method according to claim 4 or 5 comprising a mold in at least two parts (50, 51), an injection device (52) of synthetic material, a device (56) for closing the cap (5) of the closure cap and a device for ejecting the part (1) from the mold, characterized in that it further comprises a device (53) for passing a strip (54) of semi-synthetic material permeable and a tool (55) for cutting the membrane (9).  7. Device according to claim 6, characterized in that a part of the mold (50) comprises a central core (55) which forms the tool for cutting the membrane, displaceable axially perpendicular to the joint plane of the mold, at the level from the place provided for forming the chimney (8) of the closure cap carrying the membrane, and in that this central core (55) comprises a device (60) for retaining the cut membrane (9), and serves as a mold wall supporting the membrane (9) during the injection of synthetic material.  8. Device according to one of claims 6 or 7, characterized in that the closure device (56) of the cap (5) of the closure cap and the device for scrolling (53) the strip of semipermeable material are mounted on the same support (59).