Mould, moulding machine and moulding method for the extrusion blow moulding

Abstract

The present invention relates to a mold (1) for manufacturing by extrusion blow molding, said mold comprising two parts (1a, 1b), said parts comprising: at least one first section (3) having a first molding surface (11, 11a, 11b) comprising at least one primary abutment zone (5) configured for forming, by pressing, a securing zone for securing at least one inner component (30) inside a parison (20); a second section (4) having a second molding surface, the second section (4) of the part (1a, 1b) of the mold (1) being movable relative to the associated at least one first section (3, 3a, 3b) of the part (1a, 1b) of the mold (1); and at least one third section (18, 18a, 18b) having a third molding surface 10 (11, 11a, 11b) comprising at least one secondary abutment zone (5b) configured for reducing, by pressing, a predetermined volume inside the parison (20), the at least one third section (18, 18a, 18b) being movable relative to the associated at least one first section (3, 3a, 3b) of the part (1a, 1b) of the mold (1).

Description

[0001] Technical field of the invention

[0002] The present invention relates to a mold for manufacturing, from a parison, by extrusion blow molding, a hollow body of a tank made of plastic material for a motor vehicle, the tank comprising at least one internal component which is fixed inside the parison when the hollow body is molded. More particularly, the present invention relates to a mold comprising two parts comprising a plurality of sections which internally delimit a molding cavity comprising a total molding surface which is intended to reproduce a predetermined shape of the hollow body to be manufactured.

[0003] The present invention also relates to a molding machine for molding, from a parison, by extrusion blow molding, a hollow body of a tank made of plastic material for a motor vehicle.

[0004] Finally, the present invention relates to a molding method for molding, from a parison, by extrusion blow molding, a hollow body of a tank made of plastic material for a motor vehicle, the tank comprising at least one internal component which is fixed inside the parison when the hollow body is molded.

[0005] BACKGROUND OF THE INVENTION

[0006] In document WO 2008 / 138869, the applicant describes a mold for manufacturing a fuel tank equipped with an internal component. The mold cavity of this mold comprises a plurality of movable bars, a bearing surface being provided at the free end of each movable bar for locally pushing the parison in a molten state and bringing it into contact with a zone of the internal component, in order to form, by pressing, the fixing of the internal component inside the parison. Another example is described in document US 2014 / 265052.

[0007] Since the bearing surface of the movable bars is limited by their cross section, the more zones of the internal component that have to be fixed, the more movable bars have to be provided. The free end of the movable bars generally has a bearing surface of about 4000 mm 2 , which represents less than 2% of the total surface of the mold. With six movable bars, it is also less than 12% of the total surface of the mold. Similarly, the more internal components the internal component as a whole comprises, the more movable bars have to be provided. This is not satisfactory since the design of the mold becomes more complex and its manufacture becomes more expensive.

[0008] Furthermore, the Applicant has found that, at the point where the parison is pushed by the movable rods towards the inner part region, the material of the parison is stretched towards the fixing region, so that the parison has a reduced thickness at the fixing. This is not desirable, because the reduction of the material thickness at the fixing can lead to an insufficient fixing of the inner part. Moreover, the reduction of thickness observed at the fixing is usually accompanied by a further deformation. This further deformation is a corrugation of the material around the fixing. This is also not desirable, because the more deformations the tank is subjected to during its manufacturing, the lower the mechanical resistance of the obtained tank. The above risks are obviously exacerbated by the multiplication of the movable rods.

[0009] The Applicant has also found that, since the movable rods are not part of the mold cooling circuit, the multiplication of the movable rods leads to a worsening of the uniformity of the mold cooling temperature. This is not satisfactory, because a worsening of the uniformity of the mold cooling temperature is liable to cause deformations of the tank during its manufacturing.

[0010] A further drawback of the above mold is that the multiplication of the movable rods leads to a multiplication of the mechanisms for moving the movable rods, which leads to an increase in size and complexity of the extrusion blow molding machine equipped with such a mold.

[0011] Therefore, it can be understood that the manufacturing cost of a tank equipped with one (or more) inner part increases with the number of movable rods needed to fix the inner part.

[0012] Furthermore, the document WO 2008 / 138869 illustrates a manufacturing process of a fuel tank of the "saddle tank" type, comprising a recess (also called "tunnel" of the tank) for the passage of a transmission shaft of a motor vehicle equipped with such a tank. In manufacturing a tank of this type, in order to reduce the predetermined volume inside the parison, the parison is pressed between the two cavities of the mold so as to subsequently form the recess of the saddle tank. The predetermined volume inside the parison is reduced during the closing of the mold carrying the two cavities of the mold. In other words, the recess must be formed at the same time as the rest of the saddle tank. This is not satisfactory in terms of flexibility of the manufacturing process, because it is not always desirable to form the recess at the same time as the rest of the saddle tank. Indeed, in the document WO 2008 / 138869, the inner part is carried by a support which must be stowed before the mold is completely closed, in order to avoid interference between the mold and the support. Therefore, the manufacturing process described in the document WO 2008 / 138869 does not allow to fix an inner part which is located, for example, only on the upper part of the mold, because in this case the mold must be closed on the support, which would lead to damage of the mold and / or of the support. SUMMARY

[0013] The object of the present invention is in particular to overcome the aforementioned drawbacks by providing a mold which ensures the manufacturing, without deformation and at low cost, of a tank comprising one (or more) internal component, regardless of the fixed number of internal components inside the parison, while providing flexibility in the manufacturing process of the tank.

[0014] To this end, the present invention relates to a mold for manufacturing, from a parison by extrusion blow molding, a hollow body of a tank made of plastic material for a motor vehicle, said tank comprising at least one internal component fixed inside the parison at the time of molding the hollow body, said mold comprising two parts movable relative to each other, said two parts internally delimiting a total molding surface when they are closed against each other, said total molding surface being intended to reproduce the predetermined shape of the hollow body to be manufactured, at least one of the parts of the mold comprising:

[0015] - at least one first section having a first molding surface for molding a first portion of the hollow body to be manufactured, said first molding surface comprising at least one main abutment zone configured for forming, by pressing, a fixing zone for fixing the at least one internal component inside the parison;

[0016] - a second section having a second molding surface for molding a second portion of the hollow body to be manufactured, said second section of the part of the mold being movable relative to the associated at least one first section of the part of the mold at least between an intermediate closed position and a final closed position of the part of the mold; and

[0017] - at least one third section having a third molding surface for molding a third portion of the hollow body to be manufactured, said third molding surface comprising at least one secondary abutment zone, said at least one third section of the part of the mold being movable relative to the associated at least one first section of the part of the mold at least between an intermediate position and a final position in which said at least one secondary abutment zone is configured to reduce, by pressing, a predetermined volume inside the parison.

[0018] Advantageously, according to the invention, the mold makes it possible to fix one or more internal components without the need to use a plurality of movable rods, these movable rods being replaced by the at least one first section of the mold, which has a molding surface large enough to be able to simultaneously press the parison against a plurality of fixing zones of the one or more internal components.

[0019] In addition to the cost savings, the application makes it possible to avoid local deformation of the material of the parison when bringing the parison into contact with the zones to be fixed, since the first molding surface extends between the different fixing zones for fixing one or more internal components inside the parison, i.e. notably comprises the different fixing zones for fixing one or more internal components inside the parison. Thanks to this arrangement, the thickness of the material at each fixing zone is not reduced and the material waviness around this fixing zone is avoided.

[0020] Another advantage of the mold according to the application is that it makes it possible to avoid an increase in the size and complexity of the extrusion blow molding machine equipped with such a mold, whatever the number of fixing zones of the future tank and the number of internal components.

[0021] Another advantage of the mold according to the application is that it makes it possible to reduce the predetermined volume inside the parison by using the pressing of at least one third portion of the mold, independently of the closing of the mold. Thus, when reducing the predetermined volume inside the parison, the deformation of the parison at the reduction can be controlled independently of the deformations to which the parison is subjected at other locations of the parison. This is particularly advantageous for a mold for manufacturing a hollow main body of a "saddle tank" made of plastic material for a motor vehicle by extrusion blow molding. Indeed, thanks to the application, the recess of the saddle tank does not have to be formed at the same time as the rest of the saddle tank. Thus, the deformation of the parison achieved by the third portion of the mold at the formation of the recess of the saddle tank is controlled and this control is independent of the deformations to which the parison is subjected at other locations of the parison. Moreover, fixing said at least one internal component before forming the recess of the saddle tank makes it possible to fix at least one internal component located in the upper portion of the mold only. Indeed, by forming the recess of said tank after fixing said at least one internal component and not at the same time, the possibility of interference between the mold and the support of said at least one internal component can be eliminated.

[0022] The application can also comprise one or more of the following optional features, alone or in combination.

[0023] The first molding surface of the portion of the mold comprises a plurality of main abutment zones and is configured so that the main abutment zones form, by pressing, simultaneously a plurality of fixing zones for fixing said at least one internal component inside the parison. Thus, the first molding surface of the portion of the mold allows fixing one or more internal components, each having a plurality of fixing zones. Moreover, the first molding surface of this portion of the mold can be modularly configured.

[0024] The first molding surface of the portion of the mold can be configured to extend along an external surface comprising the main contact area associated with the portion of the mold. Thus, each portion comprising a first molding surface has a single surface facing the parison in the intermediate closed position, so as to simultaneously fix the parison according to the predetermined fixing areas or all the fixing areas of the at least one internal part by means of the respective discrete main contact areas of the first molding surface of the portion of the mold.

[0025] The external surface of the first molding surface of the portion of the mold can comprise a predetermined edge distance (margin) around at least the main contact area of the at least one internal part associated with the portion of the mold, so as to limit the undulation of the material around each fixing area. Thus, it should be understood that the first molding surface comprises a single surface which is wider around the fixing areas of the at least one internal part, so as to avoid too pronounced undulation differences in the vicinity of the fixing areas of the at least one internal part inside the parison. Said predetermined margin around at least the main contact area can be comprised between 1 mm and 60 mm.

[0026] The external surface of the first molding surface of at least one portion of the mold is at least equal to 15% of the total molding surface. Obviously, according to the embodiment, i.e. if one portion of the mold or two portions of the mold comprise at least one first sub-portion, the total percentage of this at least one first sub-portion of the mold will be at least equal to 15% of the total molding surface or at least equal to 30% of the total molding surface, respectively. Preferably, the external surface of the first molding surface of the portion of the mold is comprised between 20% and 40% of the total molding surface. According to the embodiment, the external surface of the first molding surface of at least one of the portions of the mold is for example equal to 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39% or 40% of the total molding surface.

[0027] Said secondary abutment zones or at least one of them are configured for contacting two opposite regions of the parison so as to locally weld them to each other when the third portion of the mold part is in the final position. Thus, it is possible to easily locally weld two opposite regions of the parison when necessary, for example to locally reinforce a tank or to create a noise-proof bulkhead. This local welding is sometimes referred to in English by the terms "kiss off" or "kiss point". Preferably, each part of the mold comprises at least one third portion having at least one secondary abutment zone configured for pressing two opposite regions of the parison between them so as to locally weld them to each other when the corresponding third portion of each mold part is in the final position.

[0028] The third molding surface of the part of the mold comprises a plurality of secondary abutment zones. Thus, the third molding surface of the part of the mold can be configured in a modular manner.

[0029] The third molding surface of the part of the mold is configured so that the secondary abutment zones form, by pressing, a plurality of fixing zones of at least one internal component inside the parison at predetermined volume reductions of the parison. Thus, the third molding surface of the part of the mold allows fixing one or more internal components, each having one or more fixing zones.

[0030] The third molding surface of the part of the mold is configured so that the secondary abutment zones form, by pressing, a plurality of fixing zones of the parison to itself inside the parison at predetermined volume reductions of the parison inside. Thus, the third molding surface of the part of the mold allows creating such a tank in which one wall is fixed to an opposite wall.

[0031] Said at least one third portion of the part of the mold is divided into a plurality of sub-portions separated from each other and each secondary abutment zone is carried by one of the sub-portions of said at least one third portion. Thus, it is possible to make the plurality of secondary abutment zones independent of each other.

[0032] The sub-portions of said at least one third portion are movable relative to each other between an intermediate position and a final position. Thus, it is possible to better control the deformation of the parison at the volume reductions and to limit the stretching of the parison when reducing the predetermined volume inside the parison.

[0033] According to a first embodiment, each portion of the mold can comprise at least one first sub-portion, a second sub-portion and at least one third sub-portion. According to a second embodiment, only one of the portions of the mold comprises at least one first sub-portion, a second sub-portion and at least one third sub-portion. Typically, in the second embodiment, a first portion of the mold can comprise at least one first sub-portion, a second sub-portion and at least one third sub-portion, and a second portion of the mold can comprise a single monolithic sub-portion.

[0034] In the final closed position, the at least one first mold sub-portion of each portion of the mold is preferably surrounded by the associated second mold sub-portion of this portion of the mold. Thus, the at least one internal component is completely enclosed in the hollow body.

[0035] In the final closed position, the at least one third mold sub-portion of each portion of the mold is preferably surrounded by the associated at least one first sub-portion of this portion of the mold. Thus, the mold is more compact.

[0036] In the first embodiment, the at least one first mold sub-portion of each portion of the mold can comprise at least one main abutment zone configured for pressing the parison against the same at least one internal component to form at least two distinct anchoring zones of the same at least one internal component in order to anchor the same at least one internal component inside the parison when the hollow body is molded. It will be understood that the at least one main abutment zone of the at least one first sub-portion of the first portion of the mold can thus be aligned, i.e. directly below, at least one portion of the main abutment zone of the at least one first sub-portion of the second portion of the mold in order to simultaneously anchor two approximately opposite zones of the internal component in two separate zones inside the parison. Thus, the first mold sub-portion acts as a vice for fastening the at least one internal component.

[0037] Regardless of the embodiment, the at least one first and / or third sub-portion of the portion of the mold can comprise at least one suction element, in particular in one of the main abutment zone and / or the secondary abutment zone, which is intended to suck the parison when the hollow body is molded. Thus, the parison is better adapted to the first and / or third molding surface, which also avoids local deformations of the parison.

[0038] At least one first and / or third subpart of the part of the mold can comprise a piece of element chosen from among the following elements: a gripping element, a heating element, a combined gripping and heating element. This piece, intended to be molded with the first and / or third part of the hollow body, can or can not be the at least one internal component. Thus, the piece can be connected to the first and / or third part of the hollow body when the hollow body is molded. In one example, the gripping element is a clamp or a suction element, while the heating element is an electric heater. In one example, the piece is a metal fastener or a fiber reinforcement. In another example, the heating element is a hydraulic heater.

[0039] At least one first and / or third subpart of the part of the mold can comprise a blowing tool intended to introduce a pressurized gas inside the parison. In one example, this blowing tool is a blowing needle. In the case where a blowing tool is needed, this arrangement makes it possible to avoid placing the blowing tool in the second mold subpart, since this would lead to a decrease in the evaporative and mechanical performance of the tank obtained, and also increases the risk of the tank undergoing deformations during its manufacture.

[0040] At least one first and / or third subpart of the part of the mold can comprise first cooling means intended to cool the first and / or third part of the hollow body. This makes it possible to avoid any deformation of the first and / or third part of the hollow body during its manufacture.

[0041] The second subpart of the part of the mold can comprise second cooling means intended to cool the second part of the hollow body. This allows any deformation of the second part of the hollow body during its manufacture to be avoided.

[0042] Advantageously, the first cooling means and the second cooling means belong to the same cooling circuit. This makes it possible to homogenize the temperature of the mold.

[0043] At least one first and / or third subpart of the part of the mold can comprise a plurality of first and / or third subparts in order to improve the modularity of the mold.

[0044] The application also relates to a molding machine for molding a hollow body of a tank made of plastic material for a motor vehicle from a parison by extrusion blow molding, characterized in that the molding machine comprises a mold as described above. The molding machine thus benefits from all the advantages associated with the mold.

[0045] Finally, the application relates to a molding method for molding, from a parison by extrusion blow molding, a hollow body of a tank made of plastic material for a motor vehicle, said tank comprising at least one internal component which is fixed inside the parison when the hollow body is molded, characterized in that it comprises the following steps:

[0046] a) introducing the at least one internal component and the parison in a molten state into a mold opened into two parts, so that the at least one internal component is surrounded by the parison, at least one of the parts of the mold comprising at least one first part, a second part and at least one third part, which respectively internally delimit a first molding surface, a second molding surface and a third molding surface of a total molding surface of the mold;

[0047] b) moving the at least one first part of the parts of the mold so that the mold is in an intermediate closed position in which the at least one first part of the parts of the mold presses the parison against the at least one internal component to fix the at least one internal component inside the parison, the first molding surface being configured for simultaneously forming, by pressing, a plurality of fixing zones of the at least one internal component inside the parison;

[0048] c) moving the second part of the parts of the mold relative to the at least one first part of the parts of the mold so that the mold is in a final closed position in which the two parts of the mold are closed against each other to internally delimit the total molding surface intended to reproduce a predetermined shape of the hollow body to be manufactured;

[0049] d) moving the at least one third part of the parts of the mold relative to the at least one first part of the parts of the mold so that the at least one third part is in a position in which the third molding surface presses the parison to reduce a predetermined volume inside the parison;

[0050] e) making the parison conform to the total molding surface of the mold by means of a pressurized gas, thereby implementing a blow molding of the parison;

[0051] f) opening the mold to extract the hollow body manufactured.

[0052] Preferably, the steps a) to f) of the molding method according to the application are carried out sequentially.

[0053] The molding method according to the application preferably uses an extruded parison. According to the application, each internal part is surrounded by a parison, either by extruding the parison around each internal part or by inserting each internal part into a parison. In the case where the internal part is inserted into the parison, the parison can be introduced into the open mold by a robot.

[0054] The extruded parison can be stretched so as to not risk colliding with the internal part when it is inserted, which can be achieved by suitable means. In one example, the molding method according to the application uses a tool capable of stretching the parison so as to keep it open, such as the tool of the type referenced as 6 in document WO 2008 / 138869, for example. This tool can comprise clamps, pincers or claws that easily take hold of the edges of the parison and keep these edges apart. This tool can be controlled by a robot.

[0055] The application can also comprise one or more of the following optional features, alone or in combination.

[0056] Preferably, a pressurized gas is introduced inside the parison so as to pre-blow the parison between the step a) and the step b). This introduction of gas can be carried out according to the step b) of document WO 2008 / 138869, so as to expand the parison, in particular by homogenizing the thickness of the parison. By way of non-limiting example, the introduction of gas for pre-blowing can be obtained by the blowing tool used to carry out the step e), by a dedicated tool mounted on the mold, by a hollow support rod of the internal part or by a nozzle comprised in the extrusion head of the parison.

[0057] In the step b), the at least one internal part can be fixed inside the parison by welding, bouterollage or mechanical anchoring.

[0058] In a preferred embodiment of the method according to the application, the at least one third portion of the portion of the mold is divided into a plurality of sub-portions, the plurality of sub-portions being movable relative to each other between an intermediate position and a final position, and the third molding surface comprises a plurality of secondary abutment areas, each secondary abutment area being carried by one sub-portion of the at least one third portion. By means of this arrangement, in the intermediate position, each secondary abutment area can be brought into contact with the parison so as to prevent the parison from expanding and stretching in an uncontrolled manner at the location where the predetermined volume inside the parison is reduced by pressing, for example during a pre-blowing step. Furthermore, each secondary abutment area can be guided to the final position so as to reduce the predetermined volume inside the parison by pressing. Thus, as the predetermined volume inside the parison is reduced, the deformation and stretching of the parison at the location of the reduction are also better controlled.

[0059] BRIEF DESCRIPTION OF DRAWINGS

[0060] Other features and advantages of the present application will appear clearly from the following description, made by way of non-limiting example, with reference to the appended drawings in which:

[0061] - Figure 1 is a partial transparent side view of a mould according to a first embodiment of the application in the open position;

[0062] - Figure 2 is a partial transparent side view of a mould according to a first embodiment of the application in the intermediate closed position;

[0063] - Figure 3 is a front view of a portion of a mould according to a first embodiment of the application in the open position;

[0064] - Figure 4 is a perspective view of a portion of a mould according to a first embodiment of the application in the open position;

[0065] - Figures 5 to 7 is a schematic sectional view of a first embodiment of a mould according to the application in different successive positions;

[0066] - Figures 8 to 10 is a schematic sectional view of a second embodiment of a mould according to the application in different successive positions;

[0067] - Figure 11 is a sectional view of a portion of a mould according to the application showing a suction element;

[0068] - Figure 12 is a sectional view of a portion of a mould according to the application showing a blow tool;

[0069] - Figure 13 is a sectional view of a portion of a mould according to the application showing a holding element in a non-actuated state;

[0070] - Figure 14 is a sectional view of a portion of a mould according to the application showing a holding element in an actuated state;

[0071] - Figure 15 is a sectional view of a portion of a mould according to the application showing a holding and electric heating combined element in a non-actuated state;

[0072] - Figure 16 is a sectional view of a portion of a mould according to the application showing a holding and hydraulic heating combined element in a non-actuated state;

[0073] - Figure 17 is a sectional view of a portion of a mould according to the application showing a cooling device;

[0074] - Figures 18 to 21 is a schematic cross-sectional view of a third embodiment of a mould according to the present application in different consecutive positions;

[0075] - Figures 22 to 25 is a schematic cross-sectional view of a fourth embodiment of a mould according to the present application in different consecutive positions;

[0076] - Figure 26 and Figure 27 is a schematic cross-sectional view of a fifth embodiment of a mould according to the present application in a final position, the cross-section being taken through the partial weld.

[0077] Detailed description of at least one embodiment of the present application

[0078] In the different figures, identical or similar elements have the same reference signs and possibly an index added. Therefore, the description of their structure and function is not systematically repeated.

[0079] In the following, the orientation is that of the figures. In particular, the terms "upper", "lower", "left", "right", "above", "below", "forward" and "backward" are generally understood with respect to the direction represented by the figures.

[0080] By "tank" is meant a sealed tank suitable for storing a fluid under various different conditions of use and environment. The tank made with the mould according to the present application is made of a wall of plastic material. The tank wall has an inner surface and an outer surface. The inner surface is the surface facing the inner volume of the tank, while the outer surface is the surface facing the outer volume of the tank.

[0081] By "plastic material" is meant any material comprising at least one polymer made of synthetic resin. All types of plastic material can be suitable. Very suitable plastic materials belong to the category of thermoplastic materials.

[0082] By "thermoplastic material" is meant any thermoplastic polymer, including thermoplastic elastomers and mixtures thereof. The term "polymer" refers both to homopolymers and to copolymers (in particular binary or ternary copolymers). Examples of such copolymers are random copolymers, sequential copolymers, block copolymers and graft copolymers, but are not limited thereto.

[0083] Any type of thermoplastic polymer or copolymer having a melting temperature lower than a decomposition temperature is suitable. Synthetic thermoplastic materials spanning at least 10 degrees Celsius (10 °C) in the melting range are particularly suitable. As examples of such materials, materials having a molecular weight polydispersity can be found.

[0084] In particular, polyolefins, thermoplastic polyesters, polyketones, polyamides and copolymers thereof can be used. Mixtures of polymers or copolymers can also be used, as well as mixtures of polymeric materials with inorganic, organic and / or natural fillers, such as, but not limited to, carbon, salts and other inorganic derivatives, natural or polymeric fibres. Multilayer structures consisting of a plurality of stacked and connected layers can also be used, the structure comprising at least one of the above-mentioned polymers or copolymers.

[0085] A frequently used polymer is polyethylene. Excellent results have been obtained using high-density polyethylene (HDPE).

[0086] In one example, the tank manufactured using the mould according to the present application is a fuel tank comprising a multilayer structure comprising at least one layer of thermoplastic material and at least one additional layer, which can advantageously be made of a material having a barrier effect with respect to liquids and / or gases. Preferably, the properties and thickness of the barrier layer are chosen so as to limit the permeability of the liquids and gases in contact with the tank wall to the greatest extent possible. Preferably, the layer is based on a barrier material, i.e. a fuel-impermeable resin, such as EVOH (ethylene-vinyl acetate copolymer partially hydrolysed). Alternatively, the tank can be surface-treated (fluorinated or sulphonated) with the aim of making it impermeable to fuel.

[0087] By "preform" is meant a preform of a single piece, generally extruded and substantially tubular in shape, which is intended to constitute the tank wall after moulding, i.e. after the operation intended to give the preform in the molten state the shape and dimensions required for the tank to be made by means of the mould.

[0088] By "internal component" is meant a component intended to perform a function in the tank, such as venting, stiffening, pumping a fluid, measuring the position of a fluid, reducing the noise associated with the fluid waves in the tank. In one example, the internal component is a stiffening column connecting opposite sides of the inner surface of the tank.

[0089] By "first part", "second part" and "third part" of the mould are meant respectively a first moulding element, a second moulding element and a third moulding element located in at least one portion of the mould.

[0090] By "first moulding surface" is meant the inner surface of the at least one first part of the mould, which delimits a moulding space for moulding the first portion of the hollow body. The inner surface comprises a base and portions projecting on the base.

[0091] By "second moulding surface" is meant the inner surface of the second part of the mould, which delimits a moulding space for moulding the second portion of the hollow body. The inner surface comprises a base and portions projecting on the base.

[0092] By "third molding surface" is meant the inner surface of the third portion of the mold which delimits a molding space for molding the third part of the hollow body. This inner surface comprises a bottom and a portion protruding on this bottom.

[0093] By "first molding surface is at least equal to 15% of the total molding surface" is meant that the area of the first molding surface is greater than or equal to 15% of the area of the total molding surface, while being strictly less than 100% of the area of the total molding surface.

[0094] Advantageously, the sum of the molding surfaces of the two portions of the mold is equal to the total molding surface. Thus, the two portions of the mold are sufficient to manufacture the entire tank hollow body.

[0095] By "plastic welding" is meant a set of techniques for welding two parts made of thermoplastic material. As an example, in the case where the materials of the internal part and of the parison are compatible with welding, plastic welding can be applied by pressing, through the pressing of each main bearing area of the at least one first portion of the mold, a contact pressure at the interface between the inside of the parison in a molten state and the region to be fixed of the at least one internal part. In order to facilitate plastic welding, the region to be fixed of the at least one internal part is preferably preheated to soften and melt.

[0096] By "bouterollage" is meant a set of techniques for fixing an internal part to a parison, especially in the case where the materials of the internal part and of the parison are not compatible with welding, by pressing, through the pressing of each main bearing area of the at least one first portion of the mold, a portion of the parison into a recess (évidement) of the internal part by creep of the parison. After solidification of the parison, the bouterollage can prevent the part from detaching from the solidified parison due to the shape of the recess. In documents WO2007 / 090453 and WO2010 / 066593, examples of a part recess and of a solidified shape of the parison are respectively designated by reference signs 3 and 5. Figure 1 and Figure 2 In documents WO2007 / 090453 and WO2010 / 066593, examples of a part recess and of a solidified shape of the parison are respectively designated by reference signs 3 and 5.

[0097] By "mechanical anchoring" is meant a set of techniques for fixing an internal part to a parison, especially in the case where the materials of the internal part and of the parison are not compatible with welding, by pressing, through the pressing of each main bearing area of the at least one first portion of the mold, a portion of the internal part into the parison by creep of the parison. After solidification of the parison, the mechanical anchoring can prevent the internal part from detaching from the solidified parison due to the shape of the internal part entering the parison. In document EP1211196, examples of an entering portion of the internal part and of a solidified shape of the parison are respectively designated by reference signs 102 and 116. Figure 10

[0098] ​The extrusion blow-molded parts are used in a conventional manner known to the person skilled in the art, except as indicated in the present description. Thus, the conventional parts are not systematically described in the present description, such as internal part supports (e.g. rods), blow-molding devices, parison manufacturing devices, parison separation and guiding devices around the internal parts, or parison sealing devices for carrying out pre-blowing, as explained in for example document WO 2008 / 138869 (see in particular references 3, 6, 7 and 7’).

[0099] The following embodiments are all examples. Although the description makes reference to one or more embodiments, this does not necessarily mean that each reference sign relates to the same embodiment, or that a feature is only applicable to a single embodiment. Simple features of different embodiments can also be combined and / or interchanged to provide other embodiments.

[0100] In the present description, certain elements or parameters can be indexed by a first or second element, and a first and second parameter, or a first and second criterion, etc. In this case, this is a simple index for distinguishing and naming similar but not identical elements or parameters or criteria. This index does not imply a priority of one element, parameter or criterion over another, and the names can be easily interchanged without departing from the scope of the present description. This index also does not imply a chronological order, for example for evaluating a certain criterion.

[0101] Figures 1 to 17 Only the first and second sections are shown. The third section is shown in Figures 18 to 25 .

[0102] Figure 1 and Figure 2 A mold 1 is shown for manufacturing, by extrusion blow-molding of a parison 20, a hollow body 10 of a tank made of plastic material for a motor vehicle, the tank comprising at least one internal part 30 fixed inside the parison when the hollow body is molded. More particularly, Figure 1 The mold 1 is shown in an open position, Figure 2 The mold is shown in an intermediate closed position. As described hereafter, when the mold 1 is in a final closed position, the hollow body 10 is obtained (as Figure 7 and Figure 10 ).

[0103] The mold 1 comprises two parts 1a and 1b that are movable relative to each other, when they are closed against each other (as can be seen in Figure 7 and Figure 10 , they internally delimit a total molding surface or mold cavity 2 that is intended to reproduce the predetermined shape of the hollow body 10 to be manufactured.

[0104] According to the application, at least one of the portions 1a, 1b of the mold 1 comprises:

[0105] - at least one first sub-portion 3a, 3b having a first molding surface 11, 11a, 11b for molding a first portion of the hollow body 10 to be manufactured, said first molding surface 11, 11a, 11b comprising at least one main abutment zone 5a configured to form, by pressing, a fixing zone for fixing the interior of the parison 20 with said at least one internal component 30;

[0106] - a second sub-portion 4, 4a, 4b having a second molding surface 12, 12a, 12b for molding a second portion of the hollow body 10 to be manufactured.

[0107] The second sub-portion 4, 4a, 4b of the portion 1a, 1b of the mold 1 is movable with respect to the associated at least one first sub-portion 3, 3a, 3b of this portion 1a, 1b of the mold 1 between an intermediate closing position (shown in Figure 2 , Figure 6 and Figure 9 of the two portions 1a, 1b of the mold 1 (shown in Figure 7 and Figure 10 ) of the two portions 1a, 1b of the mold 1.

[0108] Advantageously, according to the application, the first molding surface 11, 11a, 11b of this portion 1a, 1b of the mold 1 comprises a plurality of main abutment zones 5a, as shown in Figure 3 and Figure 4 and is configured so that these main abutment zones 5a simultaneously form, by pressing, a plurality of fixing zones for fixing said at least one internal component 30 to the interior of the parison 20.

[0109] As shown in Figure 3 , the first molding surface 11, 11a, 11b of this portion 1a, 1b of the mold 1 can thus be configured to extend along an envelope surface Sc (shown in dashed lines in Figure 3 containing the main abutment zones 5a of this portion 1a, 1b of the mold 1, or even all the main abutment zones 5a associated with this portion 1a, 1b of the mold 1. Of course, Figure 3 the envelope surface Sc shown in dashed lines in

[0110] Thus, each portion 1a, 1b comprising a first molding surface 11, 11a, 11b in the intermediate closing position (as shown inFigure 2 , Figure 6 and Figure 9 the first molding surface 11, 11a, 11b of this portion la, lb of the mold 1 has a unique surface facing the parison 20 so as to simultaneously fix the parison 20 according to a plurality of predetermined fixing zones or all the fixing zones of said at least one internal part 30 by means of each discrete main abutment zone 5a of the first molding surface 11, 11a, 11b of this portion la, lb of the mold 1.

[0111] The circumscribed surface Sc of each first molding surface 11, 11a, 11b can comprise a predetermined margin around the main abutment zone 5a of said at least one internal part 30 associated with this portion of the mold 1 to limit the material undulations around each fixing zone. This predetermined margin around at least the main abutment zone 5a can be between 1 mm and 60 mm. Of course, this predetermined margin is not necessarily constant with respect to each main abutment zone 5a or between each main abutment zone. Figure 3 An example of a first surface 11 is thus shown, the predetermined margin of which is not constant around another example of a circumscribed surface Sc shown in dotted line, but the application is not limited thereto.

[0112] The circumscribed surface Sc of the first molding surface 11, 11a, 11b of at least one of the portions la, lb of the mold 1 is preferably at least equal to 15% of the total molding surface. Obviously, according to the different embodiments, i.e. if a single portion la, lb of the mold 1 or two portions la, lb of the mold 1 comprise at least one first sub-portion 3, 3a, 3b, the total percentage of this at least one first sub-portion 3, 3a, 3b of the mold 1 will be at least equal to 15% of the total molding surface or at least equal to 30% of the total molding surface, respectively. Preferably, the circumscribed surface Sc of the first molding surface 11, 11a, 11b of this portion la, lb of the mold is between 20% and 40% of the total molding surface, i.e. equal to 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39% or 40%, for example.

[0113] Figures 5 to 7 A molding machine 100 is shown for molding a hollow body 10 of a plastic material tank for motor vehicles from a parison 20 by extrusion blow molding. This machine 100 comprises the above-described mold 1 according to the first embodiment. Figure 5 The mold 1 is shown in the open position (the mold 1 is open), Figure 6 The mold 1 is shown in the intermediate closed position, Figure 7 The mold is shown in the final closed position.

[0114] In the intermediate closed position, the at least one first part 3, 3a, 3b of the mold 1 is extended with respect to the second part 4, 4a, 4b of the mold 1. In the final closed position, the second part 4, 4a, 4b of the mold 1 surrounds the at least one first part 3, 3a, 3b of the mold 1 which is in an unchanged position.

[0115] The at least one first part 3, 3a, 3b of the mold 1 comprises a main abutment zone 5a configured to press the parison 20 against said at least one internal part 30 to form at least two distinct anchoring zones to anchor the same said at least one internal part 30, so as to anchor the same said at least one internal part 30 inside the parison 20 when the hollow body 10 is molded.

[0116] Advantageously, each main abutment zone 5a is configured to allow a welding, a press-in anchoring or a mechanical anchoring to anchor said at least one internal part 30 inside the parison 20 when the hollow body 10 is molded. Thus, each main abutment zone can comprise a geometry, mechanical properties and / or a material intended to facilitate the welding, the press-in anchoring or the mechanical anchoring. As a non-limiting example, the main abutment zone 5a can comprise a flat surface whose material has a melting temperature higher than the melting temperature of the parison and of the region of the internal part to be anchored, so that at least one welding anchoring zone is formed between the parison and the region of the internal part to be anchored by pressing of the main abutment zone. Of course, the main abutment zone can also comprise, in addition or alternatively, a relief intended to facilitate the press-in anchoring and / or a recess intended to facilitate the mechanical anchoring.

[0117] The first part 1a of the mold 1 comprises at least one first part 3a of the mold 1, while the second part 1b of the mold 1 comprises at least one other first part 3b of the mold 1. The at least one first part 3a of the mold 1 is movable with respect to the at least one other first part 3b of the mold 1 between the open position and the intermediate closed position of the mold 1. The at least one first part 3a, 3b of each part 1a, 1b of the mold 1 comprises a first actuator 6 for the transition from the open position to the intermediate closed position and vice versa.

[0118] The first part 1a of the mold 1 comprises a second part 4a of the mold 1, while the second part 1b of the mold 1 comprises another second part 4b of the mold 1. The second parts 4a, 4b of the mold 1 are movable with respect to each other between the intermediate closed position and the final closed position of the mold 1. Each second part 4a, 4b of the mold 1 comprises a second actuator 7 for the transition from the intermediate closed position to the final closed position and vice versa.

[0119] In the intermediate closed position, the at least one first part 3, 3a, 3b of the mold 1 is extended with respect to the second part 4, 4a, 4b of the mold 1. In the final closed position, the second part 4, 4a, 4b of the mold 1 surrounds the at least one first part 3, 3a, 3b of the mold 1 which is in an unchanged position. Figure 11In the example shown, the at least one first part 3 of the mold comprises at least one suction element 14b in the at least one main bearing area 5a for suctioning (sucking) the parison 20 when molding the hollow body 10. It can also be seen that the bottom of the first molding surface 11 also comprises at least one suction element 14a. It can also be seen that the plurality of suction elements 14a are connected to each other and communicate via a connection 14c that connects a suction device (not shown), for example a vacuum machine. Thus, the parison 20 can better adhere to the first molding surface 11, which also avoids local deformations of the parison 20.

[0120] In Figures 13 to 16 the example shown, the at least one first part 3 of the mold 1 comprises an element of the part 31 selected from the following: a gripping element 15, a heating element 16, 16', and a combined element of gripping 15 and heating 16, 16'. The part 31 intended to be molded with the first portion of the hollow body 10 can or can not be said at least one internal component 30. The gripping element can thus be a clamp 15a or a suction element. In Figures 13 to 14 the example, the clamp 15a can be converted from an open position Figure 13 to a closed position Figure 14 in order to press the parison 20 against the part 31, as described for example in document EP3946905. Figure 15 The heating element 16 in the example is an electric heater 16a, while Figure 16 the heating element 16' in the example is a hydraulic heater 16'a for locally reheating at least the parison 20. According to one example, the part 31 is a metal fastener or a fiber reinforcement.

[0121] In Figure 12 the example shown, the at least one first part 3 of the mold 1 comprises a blow tool 13 intended to introduce pressurized gas inside the parison 20. As Figure 12 can be seen, the blow tool 13 comprises a blow needle 13a capable of piercing the parison 20 to perform step d). It can be seen that the blow needle 13a is mounted so as to be movable with respect to the first molding surface 11 by means of an actuator 13b, to pass from a retracted position in the at least one first part 3 to an extended position protruding from the bottom of the first molding surface 11 and vice versa.

[0122] In Figure 17In the example shown, at least one first portion 3 and / or second portion 4 of part 1a of mold 1 includes a cooling device 17 for cooling a portion of the hollow body 10. The at least one first portion 3a of mold 1 includes a cooling element 17a for cooling a first portion of the hollow body 10. The second portion 4a of mold 1 includes a cooling element 17b for cooling a second portion of the hollow body 10. Of course, cooling elements 17a and 17b may belong to the same hydraulic circuit as the cooling device 17.

[0123] Figures 8 to 10 A second embodiment of mold 1 is shown. This second embodiment differs from the first embodiment in that the second portion 1b of mold 1 is formed as a single-piece segment 8. In other words, relative to... Figures 5 to 7 In the first embodiment, Figures 8 to 10 The single-unit section 8 replaces at least one first section 3b and the second section 4b of section 1b of mold 1. This allows for simplification of mold 1 by reducing the number of parts required for its construction.

[0124] Figures 18 to 21 A third embodiment of mold 1 is shown. The difference between this third embodiment and the first embodiment is that mold 1 is a mold for manufacturing the hollow body 10 of a "saddle-shaped storage tank" made of plastic material for motor vehicles from a preform 20 by extrusion blow molding.

[0125] A portion 1a of mold 1 includes at least one third portion 18, 18a having third molding surfaces 19, 19a for molding a third portion of the hollow body 10 to be manufactured. The third molding surfaces 19, 19a include at least one secondary abutment region 5b. The at least one third portion 18, 18a of portion 1a of mold 1 is movable relative to the associated at least one first portion 3, 3a of portion 1a of mold 1, at least between an intermediate position and a final position. In the final position, the at least one secondary abutment region 5b is configured to reduce a predetermined volume inside the preform 20 by pressing.

[0126] exist Figures 18 to 25 In the examples shown, the third molding surfaces 19, 19a of portion 1a of mold 1 include a plurality of secondary abutment regions 5b. In these examples, the first portion 1a of mold 1 includes at least one first segment 3a, a second segment 4a and at least one third segment 18a, and the second portion 1b of mold 1 includes a second segment 4b and a single monolithic segment that incorporates the at least one first segment 3b and the at least one third segment 18b.

[0127] Figures 18 to 21Also shown is a portion of a molding machine 100 which molds a hollow body 10 of a saddle-shaped tank made of plastic material for motor vehicles from a parison 20 by extrusion blow molding. The machine 100 comprises the mold 1 described above according to the third embodiment. Figure 18 The mold 1 is shown in the open position (mold 1 open), Figure 19 The mold 1 is shown in the intermediate closed position, Figure 20 The mold 1 is shown in the final closed position. Figure 20 Also shown is the at least one third portion 18 of the portion la of the mold 1 in the intermediate position, Figure 21 The at least one third portion 18 of the portion la of the mold 1 is shown in the final position.

[0128] In the final closed position of the two portions la, lb of the mold 1 in the above-described example, the second portions 4, 4a, 4b of the mold 1 surround the at least one first portion 3, 3a, 3b of the mold 1 and the at least one first portion 3, 3a, 3b of the mold 1 surrounds the at least one third portion 18, 18a, 18b, so that the first molding surface 11, 11a, 11b and the second molding surface 12, 12a, 12b and the third molding surface 19, 19a, 19b are joined to form the total molding surface or mold cavity 2.

[0129] Figures 18 to 21 Also shown is a method of molding a hollow body 10 of a saddle-shaped tank made of plastic material for motor vehicles from a parison 20 by extrusion blow molding, the saddle-shaped tank comprising at least one internal component 30 which is fixed inside the parison 20 when the hollow body 10 is molded, the method comprising the following steps, preferably in this order:

[0130] a) introducing the at least one internal component 30 and the parison 20 in a molten state into a mold 1 which is open in two portions la, lb so that the at least one internal component 30 is surrounded by the parison 20, at least one portion la, lb of the mold 1 comprising at least one first portion 3, a second portion 4 and at least one third portion 18 which internally delimit a first molding surface 11, a second molding surface 12 and a third molding surface 19 of the total molding surface of the mold 1, respectively;

[0131] b) moving the at least one first portion 3 of the portion la, lb of the mold 1 so that the mold 1 is in an intermediate closed position in which the at least one first portion 3 presses the parison 20 against the at least one internal component 30 so as to fix the at least one internal component 30 inside the parison 20, the first molding surface 11 being configured for simultaneously forming, by pressing, a plurality of fixing regions which fix the at least one internal component 30 inside the parison 20;

[0132] c) moving the second portion 4 of the portion la, lb of the mold 1 with respect to the at least one first portion 3 of the portion la, lb of the mold 1 to bring the mold 1 in a final closed position in which the two portions la, lb of the mold 1 are closed against each other, thus delimiting internally a total molding surface of a predetermined shape intended to reproduce the hollow body 10 to be manufactured;

[0133] d) moving the at least one third portion 18 of the portion la, lb of the mold 1 with respect to the at least one first portion 3 of the portion la, lb of the mold 1 to bring the at least one third portion 18 in a position in which the third molding surface 19 presses the parison 20 to reduce the predetermined volume inside the parison 20;

[0134] e) making said parison 20 adhere to the total molding surface of the mold 1 by means of a pressurized gas, thus realizing the blow molding of the parison 20;

[0135] f) opening the mold 1 to extract the manufactured hollow body 10.

[0136] Preferably, a pressurized gas is introduced inside the parison 20 to pre-blow said parison 20 between step a) and step b). This gas introduction can be carried out according to step b) of document WO 2008 / 138869 to expand the parison, in particular by homogenizing the thickness of the parison. The gas introduction at a lower pressure than in step e) can be realized by various means known to the person skilled in the art. As a non-limiting example, the gas introduction for the pre-blowing can be obtained by the blowing tool used to carry out step e), by a dedicated tool mounted on the mold, by a hollow support rod of the internal part or by a nozzle comprised in the extrusion head of the parison.

[0137] Advantageously, in step b), said at least one internal part 30 is fixed inside the parison 20 by welding, press-fitting or mechanical anchoring.

[0138] In the final closed position of the mold 1, the blow molding of step e) is carried out at a blowing pressure of about 10 bars (1 MPa).

[0139] Preferably, the at least one third portion 18 of the portion la, lb of the mold 1 is divided into a plurality of sub-portions movable with respect to each other between an intermediate position and a final position, and the third molding surface 19 comprises a plurality of secondary abutment areas 5b, each secondary abutment area 5b being carried by one sub-portion of the at least one third portion 18.

[0140] Figures 22 to 25A fourth embodiment of the mold 1 is shown. This fourth embodiment differs from the third embodiment in that the at least one third portion 18, 18a of the portion la of the mold 1 is divided into a plurality of sub-portions separate from each other, and each secondary abutment zone 5b is carried by one of the sub-portions of the at least one third portion 18, 18a of the portion la of the mold 1.

[0141] Advantageously, according to the application, the sub-portions of the at least one third portion 18, 18a of the portion la of the mold 1 are movable relative to each other between the intermediate position and the final position.

[0142] Figure 26 and Figure 27 A fifth embodiment of the mold 1 is shown, in which the mold 1 is in the final position. The fifth embodiment differs from the third embodiment in that the secondary abutment zones 5b are configured for contacting two opposite regions of the parison 20, for locally welding them to each other, when the third portions 18, 18a, 18b of the portions la, lb of the mold 1 are in the final position. This local weld 22 is sometimes denoted by the English term "kiss off" or "kiss point", and allows for example to locally reinforce the hollow body. More particularly, and especially according to this embodiment, each portion la, lb of the mold 1 comprises at least one secondary abutment zone 5b, which is configured for pressing two opposite regions of the parison 20 between them, for locally welding them to each other, when the respective third portion 18a, 18b of each portion la, lb of the mold 1 is in the final position. Thus, it is possible to easily produce a local weld 22 which allows for example to reinforce the hollow body. It can be understood that the secondary abutment zones 5b have a particular shape which is able to contact two opposite regions of the parison 20, to allow the local weld 22. This shape varies according to the embodiment, for example according to the desired contact surface between the two opposite regions of the parison 20.

[0143] Figure 26 and Figure 27 A mold 1 in the final position is shown along a section plane passing through the local weld 22. In the current case, it is observed that this local weld 22 is able to locally connect the walls of the parison 20 which are intended to form the upper and lower walls of the hollow body 10.

[0144] Figure 27 An internal component 30 to be fixed is also shown. In this example, the internal component 30 comprises a fuel line 33 connecting two opposite portions of the internal component 30. It should be noted that the fuel line 33 is not located in the section plane passing through the local weld 22, but in another plane parallel to this section plane.

[0145] The present invention is not limited to the illustrated embodiments and variants, and other embodiments and variants will be apparent to those skilled in the art. The above-described embodiments are therefore merely examples. Although the description refers to one or more embodiments, this does not necessarily mean that each reference sign relates to the same embodiment or that a feature is only applicable to a single embodiment. Simple features of different embodiments can also be combined and / or interchanged to provide other embodiments. As a non-limiting example, in the second embodiment, it is conceivable to use a single actuator 7 to move the second part 4a towards the monolithic part 8 (so that the monolithic part 8 is stationary), to further simplify the molding machine 100. Likewise, although the description refers to the first and second embodiments, it is conceivable to combine the features of the first and second embodiments to provide a third embodiment. Figures 1 to 17 It is shown that the portions la, lb of the mold 1 present a single first part 3a, 3b, but it is conceivable that the at least one first part 3a, 3b of the mold 1 comprises a plurality of first parts 3a, 3b, for example two, three, four, five, six, seven, eight, nine or ten first parts 3a, 3b.

[0146] List of reference signs

[0147] 1 : mold

[0148] 1 a: first portion of the mold

[0149] 1 b: second portion of the mold

[0150] 2: mold cavity

[0151] 3, 3a, 3b: first part of the mold

[0152] 4, 4a, 4b: second part of the mold

[0153] 5a: main abutment area

[0154] 5b: secondary abutment area

[0155] 6: first actuator

[0156] 7: second actuator

[0157] 8: monolithic part

[0158] 9: support plate

[0159] 10: hollow body

[0160] 11, 11a, 11b: first molding surface

[0161] 12, 12a, 12b: second molding surface

[0162] 13: blow tool

[0163] 13a: blow pin

[0164] 13b: actuator of the blowing needle

[0165] 14: suction element

[0166] 14a: bottom suction element

[0167] 14b: suction element of the main abutment area 5a

[0168] 14c: connection to the suction device

[0169] 15: holding element

[0170] 15a: clamp

[0171] 15b: actuator

[0172] 16, 16': heating element

[0173] 16a: electric heater

[0174] 16b: hydraulic heater

[0175] 17: cooling device

[0176] 17a: cooling element of the first section 3a

[0177] 17b: cooling element of the second section 4b

[0178] 18, 18a, 18b: third section of the mold

[0179] 19, 19a, 19b: third molding surface

[0180] 20: parison

[0181] 21: movable part of the lower sealing device of the parison

[0182] 22: local weld

[0183] 30: inner part

[0184] 31: piece

[0185] 32: support rod of the inner part

[0186] 33: fuel line

[0187] 100: extrusion blow molding machine

Claims

1. A mold (1) for manufacturing a hollow body (10) of a storage tank made of plastic material for a motor vehicle from a preform (20) by extrusion blow molding, the storage tank including at least one internal component (30) fixed inside the preform (20) during molding of the hollow body (10), the mold (1) comprising two portions (1a, 1b) movable relative to each other, the two portions (1a, 1b) internally defining a total molding surface when closed abutting each other, the total molding surface being designed to replicate a predetermined shape of the hollow body (10) to be manufactured, at least one of the portions (1a, 1b) of the mold (1) comprising: - At least one first portion (3, 3a, 3b) having a first molding surface (11, 11a, 11b) for molding a first part of the hollow body (10) to be manufactured, the first molding surface (11, 11a, 11b) including at least one main abutment region (5a) configured to form a fixing region for fixing the at least one internal component (30) inside the preform (20) by pressing; - Second division (4, 4a, 4b), the second division (4, 4a, 4b) having a second molding surface (12, 12a, 12b) for molding a second part of the hollow body (10) to be manufactured, the second division (4, 4a, 4b) of the part (1a, 1b) of the mold (1) being movable relative to the at least one first division (3, 3a, 3b) associated with the part (1a, 1b) of the mold (1) at least between an intermediate closed position and a final closed position of the part (1a, 1b) of the mold (1); as well as - At least one third portion (18, 18a, 18b) having a third molding surface (19, 19a, 19b) for molding a third part of a hollow body (10) to be manufactured, the third molding surface (19, 19a, 19b) including at least one secondary abutment region (5b), the at least one third portion (18, 18a, 18b) of the portion (1a, 1b) of the mold (1) being movable relative to the associated at least one first portion (3, 3a, 3b) of the portion (1a, 1b) of the mold (1) between at least a middle position and a final position of the third portion, the at least one secondary abutment region (5b) of the third portion being configured to reduce a predetermined volume inside the preform (20) by pressing.

2. The mold (1) according to claim 1, wherein, The first molding surface (11, 11a, 11b) of the portion (1a, 1b) of the mold (1) is configured to extend along an outer surface that includes the main abutment region (5a) associated with the portion (1a, 1b) of the mold (1).

3. The mold (1) according to claim 2, wherein, The outer surface of the first molding surface (11, 11a, 11b) of the portion (1a, 1b) of the mold (1) includes a predetermined edge distance around the main abutment area (5a) of the at least one internal component (30) associated with the portion (1a, 1b) of the mold (1) to avoid material ripples around each fixed area.

4. The mold (1) according to claim 3, wherein, The distance between the predetermined edge of the fixed region is at least between 1 mm and 60 mm.

5. The mold (1) according to any one of claims 2 to 4, wherein, The outer surface of the first molding surface (11, 11a, 11b) of at least one portion of the mold (1) is at least 15% of the total molding surface.

6. The mold (1) according to any one of claims 1 to 4, wherein, The secondary contact area (5b) or at least one of the secondary contact areas (5b) is configured to: when the third portion (18, 18a, 18b) of the portion (1a, 1b) of the mold (1) is in the final position of the third portion, bring two opposing regions of the preform (20) into contact to partially weld the two opposing regions to each other.

7. The mold (1) according to any one of claims 1 to 4, wherein, The third molding surface (19, 19a, 19b) of the portion (1a, 1b) of the mold (1) includes a plurality of secondary abutment areas (5b).

8. The mold (1) according to claim 7, wherein, The at least one third portion (18, 18a, 18b) of the portion (1a, 1b) of the mold (1) is divided into a plurality of separate sub-parts, and each secondary abutment area (5b) is carried by a sub-part of the at least one third portion (18, 18a, 18b) of the portion (1a, 1b) of the mold (1).

9. The mold (1) according to claim 8, wherein, The sub-parts of at least one third portion (18, 18a, 18b) of the portion (1a, 1b) of the mold (1) are movable relative to each other between the intermediate position of the sub-part and the final position of the sub-part.

10. The mold (1) according to any one of claims 1 to 4, wherein, Each part (1a, 1b) of the mold (1) includes at least one first part (3, 3a, 3b), a second part (4, 4a, 4b) and at least one third part (18, 18a, 18b).

11. The mold (1) according to claim 10, wherein, Each portion (1a, 1b) of the mold (1) includes at least one first portion (3, 3a, 3b) comprising at least one main abutment region (5a) configured to press the preform (20) against the at least one internal component (30) to form at least two distinct fixing regions to fix the at least one internal component (30) inside the preform (20) during molding of the hollow body (10).

12. The mold (1) according to any one of claims 1 to 4, wherein, Only one of the portions (1a, 1b) of the mold (1) includes at least one first portion (3, 3a, 3b), a second portion (4, 4a, 4b) and at least one third portion (18, 18a, 18b).

13. The mold (1) according to any one of claims 1 to 4, wherein, In the final closed position, at least one first portion (3, 3a, 3b) of each part (1a, 1b) of the mold (1) is surrounded by an associated second portion (4, 4a, 4b) of the part (1a, 1b) of the mold (1).

14. The mold (1) according to any one of claims 1 to 4, wherein, In the final closed position, at least one third portion (18, 18a, 18b) of each part (1a, 1b) of the mold (1) is surrounded by at least one associated first portion (3, 3a, 3b) of the part (1a, 1b) of the mold (1).

15. The mold (1) according to any one of claims 1 to 4, wherein, The at least one first portion (3, 3a, 3b) of the portion (1a, 1b) of the mold (1) includes a plurality of first portions (3, 3a, 3b), and / or the at least one third portion (18, 18a, 18b) of the portion (1a, 1b) of the mold (1) includes a plurality of third portions (18, 18a, 18b).

16. A molding machine (100) for molding a hollow body (10) of a storage tank made of plastic material for a motor vehicle from a preform by extrusion blow molding, characterized in that, The molding machine includes a mold (1) according to any one of claims 1 to 15.

17. A molding method for molding a hollow body (10) of a storage tank made of plastic material for a motor vehicle from a preform (20) by extrusion blow molding, the storage tank including at least one internal component (30) fixed inside the preform (20) during molding of the hollow body (10), characterized in that, The method uses the mold (1) as described in any one of claims 1 to 15 to perform the following steps: Step a): Introduce the at least one internal component (30) and the molten preform (20) into a mold (1) that is opened into two parts (1a, 1b) such that the at least one internal component (30) is surrounded by the preform (20), and at least one part (1a, 1b) of the mold (1) includes at least one first part (3), a second part (4) and at least one third part (18), which respectively internally define a first molding surface (11), a second molding surface (12) and a third molding surface (19) of the total molding surface of the mold (1). Step b): Move at least one first portion (3) of part (1a, 1b) of the mold (1) to place the mold (1) in a closed position, in which the at least one first portion (3) of part (1a, 1b) of the mold (1) presses the preform (20) against the at least one internal component (30) to fix the at least one internal component (30) inside the preform (20), the first molding surface (11) being configured to simultaneously form a plurality of fixing areas for fixing the at least one internal component (30) inside the preform (20) by pressing; Step c): Move the second portion (4) of the portion (1a, 1b) of the mold (1) relative to the at least one first portion (3) of the portion (1a, 1b) of the mold (1) so that the mold (1) is in a final closed position where the two portions (1a, 1b) of the mold (1) close together against each other to internally define the total molding surface intended to replicate the predetermined shape of the hollow body (10) to be manufactured; Step d): Move at least one third portion (18) of the portion (1a, 1b) of the mold (1) relative to at least one first portion (3) of the portion (1a, 1b) of the mold (1) so that the at least one third portion (18) is in a position where the third molding surface (19) presses the preform (20) to reduce the predetermined volume inside the preform (20); Step e): The preform (20) is bonded to the overall molding surface of the mold (1) by means of pressurized gas, thereby realizing the blow molding of the preform (20); Step f): Open the mold (1) to remove the manufactured hollow body (10).

18. The molding method according to claim 17, wherein, Between step a) and step b), pressurized gas is introduced into the preform (20) to pre-blow mold the preform (20).

19. The molding method according to claim 17 or 18, wherein, In step b), the at least one internal component (30) is fixed inside the blank (20) by welding, press-fitting or mechanical anchoring.

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