Extrusion blow molding mold, molding machine, and molding method

Abstract

The present invention relates to a mold (1) for production by extrusion blow molding, comprising two parts (1a, 1b), the parts being at least one first section (3) having a first molding surface (11, 11a, 11b) including at least one primary bearing area (5a) configured to form, by compression, a fixation zone for at least one internal component (30) inside a parison (20), and a second section (4) having a second molding surface (12, 12a, 12b), the second section (4) of the part (1a, 1b) of the mold (1) being attached to the part (1a, 1b) of the mold (1). The mold includes a second section (4) that moves relative to at least one first section (3, 3a, 3b), and at least one third section (18, 18a, 18b) that moves relative to the at least one first section (3, 3a, 3b) associated with a portion (1a, 1b) of the mold (1), the at least one third section (18, 18a, 18b) having a third molding surface (19, 19a, 19b) that includes at least one secondary support area (5b) configured to compressively reduce a predetermined volume within the parison (20).

Description

[Technical Field]

[0001] The present invention relates to a mold for extrusion blow molding a hollow body of a plastic tank for an automobile from a parison, the tank including at least one internal component fixed inside the parison during molding of the hollow body. More specifically, the present invention relates to a mold including two parts including multiple sections defining a cavity therein including the entire molding surface for reproducing the predetermined shape of the hollow body to be manufactured.

[0002] The invention also relates to a machine for extrusion blow molding hollow bodies of plastic tanks for automobiles from parisons.

[0003] The invention further relates to a method for extrusion blow molding a hollow body of a plastic tank for an automobile from a parison, the tank comprising at least one internal component that is fixed inside the parison during molding of the hollow body. [Background technology]

[0004] In US Patent No. 5,629,599, the applicant describes a mold for manufacturing a fuel tank with an internal component. The mold cavity includes a plurality of movable rods, each with a support surface at its free end, for locally pressing the molten parison into contact with a specific zone of the internal component and fixing the internal component inside the parison by compression. Another example is described in US Patent No. 5,629,599.

[0005] The support surface of the moving rod is limited to its cross section, so the more zones of the internal components that need to be fixed, the more moving rods must be provided. The free end of the moving rod is typically about 4000 mm 2The support surface of the mold is 100 mm, which occupies less than 2% of the total mold area. Six rods occupy less than 12% of the total mold area. Similarly, the more internal components an internal component assembly contains, the more moving rods must be provided. This is unsatisfactory because it increases the mold design complexity and manufacturing costs.

[0006] Furthermore, as confirmed by the applicant, where the parison is pushed by the movable rod towards a specific zone of the internal component, the material of the parison is stretched towards this anchoring zone, resulting in a reduction in the thickness of the parison at the anchoring point. This is undesirable, as a reduction in the material thickness at the anchoring point may result in a failure of the internal component to be anchored. Furthermore, a reduction in thickness at the anchoring point often also results in another deformation: the material rippling around the anchoring point. This is also undesirable, as the more the tank is deformed during manufacturing, the lower the mechanical durability of the resulting tank. The above-mentioned risk naturally increases as the number of movable rods increases.

[0007] Furthermore, as confirmed by the applicant, the movable rods are not included in the cooling circuit of the mold, so increasing the number of movable rods will impair the uniformity of the cooling temperature of the mold, which may cause deformation of the tank during manufacturing, and this is not satisfactory.

[0008] Another disadvantage of the above mold is that as the number of movable rods increases, the number of drive mechanisms for the movable rods also increases, which makes the extrusion blow molding machine equipped with this type of mold more complex and larger in size.

[0009] Thus, it will be appreciated that the manufacturing costs of a tank with one or more internal components increases with the number of movable rods required to secure the one or more internal components.

[0010] Patent Document 1 discloses a method for manufacturing a "saddle tank" type fuel tank, which includes a recess (also called the "tunnel" of the tank) for accommodating the drive shaft of a vehicle equipped with this type of tank. During the manufacturing of this type of tank, a parison is compressed between two mold cavities to reduce its internal volume, thereby forming the recess of the saddle tank. The internal volume of the parison is reduced during the closing of a mold having two mold cavities. In other words, the recess is necessarily formed simultaneously with the rest of the saddle tank. Forming the recess simultaneously with the rest of the saddle tank is not necessarily desirable, and this is unsatisfactory from the perspective of flexibility in the manufacturing process. In fact, in Patent Document 1, the internal components are supported by supports, which must be retracted before the mold is fully closed to avoid interference between the mold and the supports. Thus, the manufacturing process described in Patent Document 1 does not allow for fixing internal components located only in the upper part of the mold, for example. This is because the mold would have to be closed on the supports, which could destroy the mold and / or the supports. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] International Publication No. 2008 / 138869 [Patent Document 2] US Patent No. 2014 / 265052 Summary of the Invention [Problem to be solved by the invention]

[0012] The main object of the present invention is to provide a mold that ensures the production of tanks containing one or more internal components at low cost and without deformation, regardless of the number of fixing points of the one or more internal components inside the parison, while providing flexibility to the tank manufacturing process, thereby eliminating the above-mentioned disadvantages. [Means for solving the problem]

[0013] To this end, the present invention relates to a mold for extrusion blow molding a hollow plastic tank for an automobile from a parison, the tank comprising at least one internal component that is fixed inside the parison during molding of the hollow body, the mold comprising two parts that are movable relative to each other and that, when the two parts are closed relative to each other, define therein a total molding surface for reproducing the predetermined shape of the hollow body to be manufactured, and at least one part of the mold: - at least one first section having a first molding surface for a first portion of the hollow body to be produced, said first molding surface including at least one primary bearing area configured to form, by compression, a fixation zone for at least one of said internal components inside the parison; a second section having a second molding surface for a second portion of the hollow body to be produced, said second section of the mold part moving relative to at least one first section associated with the mold part between at least an intermediate closed position and a final closed position of the mold part; at least one third section having a third molding surface for a third portion of the hollow body to be produced, said third molding surface including at least one secondary bearing area, said at least one third section of the mold portion moving relative to at least one first section associated with said mold portion between at least an intermediate position and a final position in which the at least one secondary bearing area is configured to compressively reduce a predetermined volume inside the parison; and Includes.

[0014] According to the invention, the mold advantageously allows one or more internal components to be fixed without the need for multiple movable rods, which are replaced by at least one first section of the mold having a molding surface large enough to simultaneously press the parison against multiple zones that fix one or more internal components.

[0015] In addition to the cost advantages, the present invention also prevents localized deformation of the parison material when the parison is brought into contact with the various fixation zones of one or more internal components, by having the first molding surface extend between, i.e., include, various zones, such that the thickness of the material in each fixation zone is not reduced, thereby avoiding rippling of the material around the fixation zones.

[0016] Another advantage of the mold according to the invention is that it avoids the complexity and size of an extrusion blow molding machine equipped with a mold of this type, regardless of the number of fixation zones and the number of internal components of the finished tank.

[0017] Another advantage of the mold of the present invention is that the use of at least one third section of the mold allows the parison's interior volume to be compressed and reduced separately from the closing of the mold. Thus, deformation of the parison during reduction of the parison's interior volume is controlled at the reduction location, independently of deformation of the parison elsewhere in the parison. This is particularly advantageous for molds used to extrusion-blow mold hollow bodies for automotive plastic "saddle tanks" from parisons. In fact, the present invention eliminates the need to simultaneously form the saddle tank cavity with the rest of the saddle tank. Thus, deformation of the parison achieved by the third section of the mold during formation of the saddle tank cavity is controlled independently of deformation of the parison elsewhere in the parison. Furthermore, by clamping at least one internal component before forming the saddle tank cavity, it is possible to clamp at least one internal component located only in the upper part of the mold. In fact, forming the tank cavity after clamping at least one internal component, i.e., with a time lag, eliminates the possibility of interference between the mold and the support for at least one internal component.

[0018] The present invention may also include any one or more of the following features, either alone or in combination.

[0019] The first molding surface of the mold section includes a plurality of primary support areas configured to simultaneously form a plurality of fixation zones of at least one of the internal components to the interior of the parison upon compression. Thus, the first molding surface of the mold section can fix one or more internal components, each internal component having a plurality of fixation zones. Additionally, the first molding surface of the mold section can be modularly manufactured.

[0020] The first molding surfaces of the mold sections can be configured to extend along a circumscribing surface that includes a primary support area associated with the mold section, such that each section including the first molding surface has only one surface facing the parison in the intermediate closed position, and each primary support area distinct from the first molding surface simultaneously secures the parison according to a predetermined plurality of securement zones or all of the securement zones of at least one of the internal components of the mold section.

[0021] The circumscribing surface of the first molding surface of the mold section may include a predetermined margin distance at least around the primary bearing area of ​​at least one of the internal components associated with the mold section to reduce rippling of material around each fixation zone. It is thus understood that the first molding surface includes a wider, single surface around the fixation zone of at least one of the internal components to prevent significant irregularities near the fixation zone of the at least one internal component to the interior of the parison. The predetermined margin distance at least around the primary bearing area may be between 1 mm and 60 mm.

[0022] The circumscribing surface of the first molding surface of at least one portion of the mold is 15% or more of the total molding surface. It is readily understood that, according to this embodiment, i.e., when only one portion of the mold or both portions of the mold include at least one first section, the combined proportion of the at least one first section of the mold may be 15% or more or 30% or more, respectively, of the total molding surface. Preferably, the circumscribing surface of the first molding surface of at least one portion of the mold is 20% to 40% of the total molding surface. In some embodiments, the circumscribing surface of the first molding surface of at least one portion of the mold is, for example, 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.

[0023] The secondary support area or at least one secondary support area is configured to bring two opposing support areas of the parison into contact with each other for local welding when the third section of the mold part is in its final position. In this way, the two opposing support areas of the parison can be easily locally welded together, for example, to locally strengthen the tank or to provide a soundproof partition, as needed. This local welding is sometimes referred to in English as a "kiss off" or "kiss point." Preferably, each mold part includes at least one third section having at least one secondary support area, and the secondary support areas are configured to press the two opposing support areas of the parison together for local welding when the respective third sections of each mold part are in their final positions.

[0024] The third molding surface of the mold section includes a plurality of secondary bearing areas, such that the third molding surface of the mold section can be manufactured modularly.

[0025] The third molding surface of the mold section is configured such that the secondary bearing area simultaneously forms, by compression, multiple fixation zones of at least one internal component into the parison at the location of the predetermined volume reduction within the parison, thereby allowing one or more internal components to be fixed by the third molding surface of the mold section, each internal component having one or more fixation zones.

[0026] The third molding surface of the mold section is configured such that the secondary support areas simultaneously form, by compression, multiple fixation zones of the parison itself within the parison at predetermined volumetric reduction locations within the parison, thereby enabling the creation of a tank whose walls are internally fixed to the opposing walls by the third molding surface of the mold section.

[0027] At least one third section of the mold part is divided into a plurality of subsections that are separated from one another, and each secondary support region is supported by one subsection of the at least one third section, so that the plurality of secondary support regions can be independent of one another.

[0028] The subsections of the at least one third section are reciprocally movable between an intermediate position and a final position, such that deformation of the parison when reducing a predetermined volume within the parison is better controlled at the point of reduction and stretching of the parison is also reduced.

[0029] According to a first embodiment, each mold part can include at least one first section, second section, and at least one third section. According to a second embodiment, only one of the mold parts can include at least one first section, second section, and at least one third section. Typically, in the second embodiment, the first mold part can include at least one first section, second section, and at least one third section, and the second mold part can include only one integral section.

[0030] At least one first section of each mold part is preferably surrounded by an associated second section of the mold part in the final closed position, such that at least one of said internal components is fully enclosed within the hollow body.

[0031] At least one third section of each mold part is preferably surrounded by at least one first section associated with the mold part in the final closed position, thus making the mold more compact.

[0032] In a first embodiment, at least one first section of each mold portion can include at least one primary bearing area configured to press the parison against the same at least one internal component to form at least two different fixation zones for the same at least one internal component within the parison during molding of the hollow body. It is understood that the at least one primary bearing area of ​​the at least one first section of the first mold portion can be aligned, i.e., vertically positioned, with at least a portion of the primary bearing area of ​​the at least one first section of the second mold portion to simultaneously fix two substantially opposing regions of the internal component in two different regions within the parison. The first mold section thus acts like a vice for clamping the at least one internal component.

[0033] Regardless of the embodiment, at least one of the first and / or third sections of the mold parts, such as in particular one of the primary and / or secondary bearing areas, can include at least one suction element for sucking the parison when molding the hollow body, so that the parison adheres firmly to the first and / or third molding surface, thereby avoiding local deformation of the parison.

[0034] At least one of the first and / or third sections of the mold portion may include at least one of the internal components, selected from among a gripping element, a heating element, and a combined gripping and heating element for a part to be molded with the first and / or third portion of the hollow body, thereby joining the part to the first and / or third portion of the hollow body during molding. In one example, the gripping element is a gripper or suction element, and the heating element is an electric heater. In one example, the part is a metal fastener or a fiber reinforcement. In another example, the heating element is a hydroheater.

[0035] At least one of the first and / or third sections of the mold portion can include a blow tool for injecting pressurized gas into the parison. In one example, the blow tool is a blow needle. If a blow tool is required, this arrangement eliminates the need to install one in the second section of the mold, which can degrade the evaporative and mechanical performance of the resulting tank and increase the risk of deformation of the tank during production.

[0036] At least one of the first section and / or third section of the mold parts may include a first cooling device for cooling the first portion and / or the third portion of the hollow body, thereby preventing deformation of the first portion and / or the third portion of the hollow body during manufacturing.

[0037] The second section of the mold portion can include a second cooling device for cooling the second portion of the hollow body, thereby preventing deformation of the second portion of the hollow body during manufacturing.

[0038] Advantageously, the first and second cooling devices are included in the same cooling circuit, which allows the temperature of the mold to be kept uniform.

[0039] At least one of the first section and / or third section of the mold portion may include multiple first sections and / or third sections to increase the modularity of the mold.

[0040] The invention also relates to a machine for extrusion blow molding hollow bodies for plastic tanks for automobiles from parisons, characterized in that the machine includes a mold as described above, thus enjoying all the advantages of this mold.

[0041] Furthermore, the present invention also relates to a method for extrusion blow molding a hollow body of a plastic tank for an automobile from a parison, the tank comprising at least one internal component that is fixed inside the parison during the molding of the hollow body, the method comprising the following steps: a) inserting the at least one internal component and the molten parison into an open two-part mold such that the at least one internal component is surrounded by the parison, the at least one part of the mold including at least one first section, a second section, and at least one third section defining, respectively, a first molding surface, a second molding surface, and a third molding surface of the overall molding surface of the mold; b) moving at least one first section of the mold portions to an intermediate closed position in which the at least one first section of the mold portions presses the parison against the at least one internal component to secure the at least one internal component within the parison, the first molding surface being configured to simultaneously form multiple fixation zones of the at least one internal component to the interior of the parison by compression; c) moving a second section of the mold portion relative to a first section of at least one of the mold portions so that the mold is in a final closed position in which the two sections of the mold are closed to define therein a total molding surface that reproduces the predetermined shape of the hollow body to be produced; d) moving the at least one third section of the mold portion relative to the at least one first section of the mold portion so that the at least one third section is in a position where the third molding surface presses against the parison to reduce the predetermined volume within the parison; e) blowing the parison by using pressurized gas to force the parison against all molding surfaces of the mold; f) opening the mold to remove the produced hollow body; The present invention is characterized by comprising:

[0042] The steps a) to f) of the molding method according to the present invention are preferably carried out continuously.

[0043] The molding method according to the present invention preferably uses an extruded parison. According to the present invention, each internal component is enclosed by a parison either by extruding the parison around the internal component or by inserting the internal component into the parison. When the internal components are inserted into the parison, the parison is guided into the open mold using a robot.

[0044] The extruded parison can be stretched to allow for the insertion of internal components without risk of collision with the parison, which can be done by a suitable device. In one example, the molding method according to the invention uses a tool capable of stretching the parison to keep it open, such as the type shown in US Pat. No. 6,619,294. The tool can be a gripper, clip or gripper that can grab the edges of the parison and hold them apart. The tool can be operated by a robot.

[0045] The invention may also include any one or more of the following features taken alone or in combination.

[0046] Preferably, pressurized gas is injected into the parison between steps a) and b) to pre-blow the parison. This type of gas injection can be performed according to step b) of Patent Document 1, particularly for the purpose of expanding the parison while maintaining a uniform thickness. Injection of gas at a lower pressure than in step e) can be performed by various methods known to those skilled in the art. As a non-limiting example, gas injection for pre-blow can be performed by a blowing tool used to perform step e), a dedicated tool attached to the mold, a hollow support rod of an internal component, or a nozzle included in the extrusion head of the parison.

[0047] In step b), the at least one internal component may be fixed inside the parison by welding, riveting or mechanical fastening.

[0048] In a preferred embodiment of the method according to the present invention, at least one third section of the mold portion is divided into a plurality of subsections that move relative to one another between an intermediate position and a final position, and the third molding surface includes a plurality of secondary support areas, each of which is supported by a subsection of at least one of the third sections. This arrangement allows each secondary support area to be guided into contact with the parison at an intermediate position, thereby preventing the parison from expanding during, for example, a pre-blowing process and from unexpectedly stretching at a point where the predetermined volume inside the parison is reduced by compression. Furthermore, each secondary support area can be guided to a final position, where compression can reduce the predetermined volume inside the parison. This allows for better control of the parison's deformation and stretching at the point where the predetermined volume inside the parison is reduced.

[0049] Other characteristics and advantages of the invention will become apparent from the following description, given by way of non-limiting reference only, with reference to the accompanying drawings, in which: [Brief explanation of the drawings]

[0050] [Figure 1] FIG. 1 is a partial side perspective view of a mold according to a first embodiment of the present invention in an open position. [Figure 2] 1 is a partial side perspective view of a mold according to a first embodiment of the present invention in an intermediate closed position. FIG. [Figure 3] FIG. 2 is a front view of a portion of a mold according to a first embodiment of the invention in an open position. [Figure 4] 1 is a perspective view of a portion of a mold according to a first embodiment of the invention in an open position. FIG. [Figure 5] 1A-1D are schematic cross-sectional views of a first embodiment of a mold according to the invention in continuously varying positions; [Figure 6] 1A-1D are schematic cross-sectional views of a first embodiment of a mold according to the invention in continuously varying positions; [Figure 7] 1A-1D are schematic cross-sectional views of a first embodiment of a mold according to the invention in continuously varying positions; [Figure 8] 5A-5C are schematic cross-sectional views of a second embodiment of a mold according to the invention in continuously varying positions; [Figure 9] 5A-5C are schematic cross-sectional views of a second embodiment of a mold according to the invention in continuously varying positions; [Figure 10] 5A-5C are schematic cross-sectional views of a second embodiment of a mold according to the invention in continuously varying positions; [Figure 11] 1 is a cross-sectional view of a portion of a mold according to the present invention showing a suction element. [Figure 12] 1 is a cross-sectional view of a portion of a mold according to the present invention showing a blow tool. [Figure 13] 1 is a cross-sectional view of a portion of a mold according to the present invention showing the gripping elements in an inactivated state. [Figure 14] 1 is a cross-sectional view of a portion of a mold according to the present invention, showing the gripping elements in an activated state; [Figure 15] 1 is a cross-sectional view of a portion of a mold according to the present invention, showing the combined gripping and electrical heating element in an inactive state. [Figure 16] FIG. 1 is a cross-sectional view of a portion of a mold according to the present invention showing the combined gripping and oil heating elements in an inactive state. [Figure 17] 1 is a cross-sectional view of a portion of a mold according to the present invention showing a cooling device. [Figure 18] 5A-5C are schematic cross-sectional views of a third embodiment of a mold according to the invention in continuously varying positions; [Figure 19] 5A-5C are schematic cross-sectional views of a third embodiment of a mold according to the invention in continuously varying positions; [Figure 20] 5A-5C are schematic cross-sectional views of a third embodiment of a mold according to the invention in continuously varying positions; [Figure 21] 5A-5C are schematic cross-sectional views of a third embodiment of a mold according to the invention in continuously varying positions; [Figure 22] 5A-5C are schematic cross-sectional views of a fourth embodiment of a mold according to the invention in continuously varying positions; [Figure 23] 5A-5C are schematic cross-sectional views of a fourth embodiment of a mold according to the invention in continuously varying positions; [Figure 24] 5A-5C are schematic cross-sectional views of a fourth embodiment of a mold according to the invention in continuously varying positions; [Figure 25] 5A-5C are schematic cross-sectional views of a fourth embodiment of a mold according to the invention in continuously varying positions; [Figure 26] 5 is a cross-sectional schematic view of a fifth embodiment of a mold according to the invention in a cross section through a local weld in a final position. [Figure 27] 5 is a cross-sectional schematic view of a fifth embodiment of a mold according to the invention in a cross section through a local weld in a final position. DETAILED DESCRIPTION OF THE INVENTION

[0051] In each drawing, identical or similar elements are designated by the same reference numerals and, if necessary, by additional letters, so that the description of their structure or function is not automatically repeated.

[0052] In the following, directions refer to the directions of the respective drawings. In particular, the terms "upper", "lower", "left", "right", "upper", "lower", "forward" and "rearward" are generally understood relative to the directions shown in the respective drawings.

[0053] "Tank" refers to a sealed tank capable of storing a fluid under varying conditions of use and environment. The tank manufactured with the mold according to the present invention is realized with a wall made of a plastic material. The tank wall has an inner surface and an outer surface. The inner surface faces the interior volume of the tank, while the outer surface faces the exterior volume of the tank.

[0054] "Plastic material" refers to any material that contains at least one synthetic resin polymer. Any type of plastic material may be suitable. Particularly suitable plastic materials belong to the category of thermoplastic materials.

[0055] "Thermoplastic material" refers to any thermoplastic polymer, including thermoplastic elastomers and mixtures thereof. The term "polymer" refers to both homopolymers and copolymers (especially binary or ternary). Non-limiting examples of such copolymers include random copolymers, sequenced copolymers, block copolymers, and graft copolymers.

[0056] Any type of thermoplastic polymer or thermoplastic copolymer with a melting point below the thermal decomposition temperature is suitable. Synthetic thermoplastic materials with a melting range above 10 degrees Celsius (10°C) are particularly suitable. Examples of this type of material include those exhibiting polydispersity in molecular weight.

[0057] Polyolefins, thermoplastic polyesters, polyketones, polyamides, and copolymers thereof, among others, can be used. Mixtures of polymers or copolymers can also be used, as can mixtures of polymeric materials with inorganic, organic, and / or natural additives, such as, but not limited to, carbon, salts, and other inorganic derivatives, natural or polymeric fibers. Multilayer structures consisting of integrated laminates containing at least one of the above polymers or copolymers can also be used.

[0058] A commonly used polymer is polyethylene, with excellent results being obtained with high density polyethylene (HDPE).

[0059] In one example, the tank produced with the mold according to the invention is a fuel tank comprising a multi-layer structure including at least one thermoplastic material layer and at least one additional layer, advantageously made of a liquid and / or gas barrier material. Preferably, the type and thickness of the barrier layer are selected to maximize the inhibition of permeation of liquids and gases in contact with the tank wall. Preferably, this layer is based on a barrier material, i.e., a fuel-impermeable resin, such as EVOH (partially hydrolyzed ethylene vinyl acetate copolymer). Alternatively, the tank can be subjected to a surface treatment (fluorination or sulfonation) to impart fuel impermeability.

[0060] "Parison" means a substantially cylindrical one-piece preform, usually extruded, intended to form the wall of a tank after molding, i.e., after the molten parison is given the required shape and size using a mold to obtain the tank.

[0061] An "internal component" is a component that has a function to perform within a tank, such as ventilation, bracing, pumping fluid, measuring fluid level, reducing noise caused by fluid waves within the tank, etc. An example of an internal component is a bracing column connecting two opposing sides of the tank's interior.

[0062] The "first section," "second section," and "third section" of a mold are the first, second, and third molding elements, respectively, located in at least one portion of the mold.

[0063] The term "first molding surface" refers to the inner surface of at least one first section of a mold that defines the molding space for the first portion of the hollow body. This inner surface includes a bottom and a portion that protrudes from the bottom.

[0064] The "second molding surface" refers to the interior surface of the second section of the mold that defines the molding space for the second portion of the hollow body. This interior surface includes the bottom and the portion that protrudes from the bottom.

[0065] The term "third molding surface" refers to the inner surface of the third section of the mold that defines the molding space for the third portion of the hollow body. This inner surface includes the bottom and the portion that protrudes from the bottom.

[0066] "The first molding surface is 15% or more of the total molding surface" means that the first molding surface area is 15% or more of the total molding surface area, and is strictly less than 100% of the total molding surface area.

[0067] Advantageously, the sum of the forming surfaces of the two parts of the mold is equal to the total forming surface of the mold, so that these two parts of the mold are sufficient to produce the entire hollow body of the tank.

[0068] "Plastic welding" refers to a general term for techniques used to weld two thermoplastic components together. One example of plastic welding involves compressing the primary bearing areas of at least one first section of a mold to apply contact pressure to the interface between the molten interior of the parison and the fixation zone of at least one of the internal components, provided that the materials of the internal component and the parison are suitable for welding. To facilitate plastic welding, the fixation zone of at least one of the internal components is preferably preheated to soften and melt it.

[0069] "Riveting" refers to a general technique used to fasten an internal component to a parison, particularly when the internal component and the parison are made of materials that are not suitable for welding, by compressing the primary support areas of at least one first section of the mold so that a portion of the parison creeps into a cutout in the internal component. The riveting prevents the component from slipping out of the parison after hardening due to the shape of the cutout. Examples of the hardened shape of the parison and the cutout in the component are shown in Figures 1 and 2 of WO 2007 / 090453, denoted by reference numerals 5 and 3, respectively.

[0070] "Mechanical fixation" refers to any technique used to fix an internal component to a parison, particularly when the internal component and parison are made of materials that are not suitable for welding. The technique involves compressing the primary support areas of at least one first section of the mold so that a portion of the internal component creeps into the parison due to parison creep. Mechanical fixation prevents the internal component from slipping out of the hardened parison due to the shape of the internal component encased within the parison as the parison hardens. Examples of the hardened shape of the parison and the encased portion of the internal component are shown in Figure 10 of EP 1211196, denoted by reference numerals 116 and 102, respectively.

[0071] Unless otherwise specified, the present specification uses conventional extrusion blow molding components known to those skilled in the art, and therefore does not generally describe conventional components such as support members (e.g., rods) for the internal components, blowing means, parison production means, parison separating and guiding means around the internal components, or parison sealing means for pre-blowing, as described, for example, in U.S. Pat. No. 5,613,299 (see, inter alia, references 3, 6, 7, and 7').

[0072] The following embodiments are exemplary. Although the specification refers to one or more embodiments, this does not necessarily mean that each reference numeral refers to the same embodiment or that each feature applies to only one embodiment. Individual features of various embodiments may be combined and / or interchanged to provide further embodiments.

[0073] In this specification, some elements or parameters may be numbered, e.g., a first element or a second element, a first parameter and a second parameter, or a first criterion and a second criterion. In this case, the numbering is merely used to distinguish and name similar but not identical elements, parameters, or criteria. This numbering does not indicate the priority of any element, parameter, or criterion over another, and such names can be easily interchanged without departing from the framework of this specification. This numbering also does not indicate, for example, a chronological order for evaluating any criteria.

[0074] Figures 1 to 17 show only the first and second sections, while Figures 18 to 25 show the third section.

[0075] Figures 1 and 2 show a mold 1 for extrusion blow molding a hollow body 10 of a plastic automotive tank from a parison 20, the tank including at least one internal component 30 that is secured within the parison during molding of the hollow body. More specifically, Figure 1 shows mold 1 in an open position, and Figure 2 shows the mold in an intermediate closed position. As explained below, hollow body 10 is obtained when mold 1 is in its final closed position (shown in Figures 7 and 10).

[0076] The mold 1 comprises two parts 1a and 1b which are movable relative to one another and which, when closed together (as shown in Figures 7 and 10), define therein a total molding surface, or cavity 2, for reproducing the predetermined shape of the hollow body 10 to be produced.

[0077] According to the present invention, at least one of the parts 1a, 1b of the mold 1 is at least one first section 3, 3a, 3b having a first moulding surface 11, 11a, 11b of a first part of the hollow body 10 to be produced, said first moulding surface 11, 11a, 11b including at least one primary bearing area 5a adapted to form, by compression, a fixing zone of at least one internal component 30 inside the parison 20; a second section 4, 4a, 4b with a second molding surface 12, 12a, 12b for a second part of the hollow body 10 to be produced; Includes.

[0078] The second sections 4, 4a, 4b of the parts 1a, 1b of the mold 1 move relative to the at least one first section 3, 3a, 3b associated with the parts 1a, 1b of the mold 1 between at least an intermediate closed position of the parts 1a, 1b of the mold 1 (shown in Figures 2, 6 and 9) and a final closed position of the parts 1a, 1b of the mold 1 (shown in Figures 7 and 10).

[0079] According to the present invention, advantageously, the first molding surfaces 11, 11a, 11b of the parts 1a, 1b of the mold 1 include a plurality of primary support areas 5a, as shown in Figures 3 and 4, which are configured to simultaneously form a plurality of fixation zones of at least one of the internal components 30 into the parison 20 by compression.

[0080] Thus, as shown in Figure 3, the first molding surfaces 11, 11a, 11b of the parts 1a, 1b of the mold 1 can be configured to extend along a circumscribing surface Sc (shown by a dotted line in Figure 3) that includes the primary bearing areas 5a of the parts 1a, 1b of the mold 1 and, in turn, all the primary bearing areas 5a associated with the parts 1a, 1b of the mold 1. Of course, the circumscribing surface Sc shown by the dotted line in Figure 3 is only an example, and the primary bearing areas 5a, instead of being connected to each other by straight segments, can also be connected by curved segments without departing from the framework of the invention.

[0081] Thus, each part 1a, 1b including the first molding surface 11, 11a, 11b has only one surface facing the parison 20 in the intermediate closed position (shown in Figures 2, 6 and 9), and each primary support area 5a, distinct from the first molding surface 11, 11a, 11b, simultaneously fixes the parison 20 according to a predetermined plurality of fixation zones or all fixation zones of at least one of said internal components 30 of the parts 1a, 1b of the mold 1.

[0082] The circumscribing surface Sc of each first molding surface 11, 11a, 11b may include a predetermined margin distance at least around the primary bearing area 5a of at least one of the internal components 30 associated with the mold 1 portion to reduce waviness of material around each fixation zone. The predetermined margin distance at least around the primary bearing area 5a may be between 1 mm and 60 mm. Of course, the predetermined margin distance is not necessarily constant for each primary bearing area 5a or between each primary bearing area. While FIG. 3 shows an example of a first surface 11, the predetermined margin is not constant around another example of the circumscribing surface Sc, as shown by the dotted line, and the invention is not limited in this respect.

[0083] The circumscribing surface Sc of the first molding surface 11, 11a, 11b of at least one part 1a, 1b of the mold 1 is preferably 15% or more of the total molding surface. It is immediately understood that according to this embodiment, i.e. when only one part 1a, 1b of the mold 1 or both parts 1a, 1b of the mold 1 comprise at least one first section 3, 3a, 3b, the total proportion of the at least one first section 3, 3a, 3b of the mold 1 amounts to 15% or more or 30% or more, respectively, of the total molding surface. Preferably, the circumscribing surface Sc of the first moulding surface 11, 11a, 11b of the mould part 1a, 1b is between 20% and 40% of the total moulding surface, i.e. for example 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39% or 40%.

[0084] 5 to 7 show a machine 100 for extrusion blow molding a hollow body 10 of a plastic tank for an automobile from a parison 20. The molding machine 100 includes a mold 1 based on the first embodiment introduced above. Fig. 5 shows the mold 1 in an open position (open mold 1), Fig. 6 shows the mold in an intermediate closed position, and Fig. 7 shows the mold in a final closed position.

[0085] In the intermediate closed position, at least one first section 3, 3a, 3b of the mold 1 protrudes from a second section 4, 4a, 4b of the mold 1. In the final closed position, the second section 4, 4a, 4b of the mold 1 surrounds the at least one first section 3, 3a, 3b of the mold 1, which does not change position.

[0086] At least one first section 3, 3a, 3b of the mold 1 includes a primary support area 5a configured to press the parison 20 against at least one internal component 30 to form at least two different fixation zones of the same at least one internal component 30 for the purpose of fixing the at least one internal component 30 inside the parison 20 during molding of the hollow body 10.

[0087] Advantageously, each primary bearing area 5a is configured to allow welding, riveting, or mechanical fastening for the purpose of securing at least one of the internal components 30 within the parison 20 during molding of the hollow body 10. Thus, each primary bearing area can include geometries, mechanical features, and / or materials that facilitate welding, riveting, or mechanical fastening. By way of example and not limitation, the primary bearing area 5a can include a flat surface made of a material with a higher melting point than the fixation zones of the parison and the internal component, such that compression of the primary bearing area results in the formation of at least one fixation zone between the parison and the internal component by welding. Of course, the primary bearing area can additionally or alternatively include protrusions that facilitate riveting and / or recesses that facilitate mechanical fastening.

[0088] The first part 1a of the mold 1 includes at least one first section 3a of the mold 1, and the second part 1b of the mold 1 includes at least one other first section 3b of the mold 1. The at least one first section 3a of the mold 1 moves relative to the at least one other first section 3b of the mold 1 between an open position and an intermediate closed position of the mold 1. The at least one first section 3a, 3b of each part 1a, 1b of the mold 1 includes a first actuator 6 for moving from the open position to the intermediate closed position and vice versa.

[0089] The first part 1a of the mold 1 includes a second section 4a of the mold 1, and the second part 1b of the mold 1 includes another second section 4b of the mold 1. The second sections 4a, 4b of the mold 1 move relative to one another between an intermediate closed position and a final closed position of the mold 1. Each second section 4a, 4b of the mold 1 includes a second actuator 7 for moving from the intermediate closed position to the final closed position and vice versa.

[0090] 11, at least one first section 3 of the mold includes at least one suction element 14b in at least one primary support region 5a for sucking the parison 20 during molding of the hollow body 10. It can also be seen that the bottom of the first molding surface 11 also includes at least one suction element 14a. Furthermore, it can also be seen that the multiple suction elements 14a are connected to one another and communicate with a suction device (not shown), such as a vacuum device, via communication channels 14c. In this way, the parison 20 adheres firmly to the first molding surface 11, preventing localized deformation of the parison 20.

[0091] In the examples shown in Figures 13 to 16, at least one first section 3 of the mold 1 includes elements selected from among gripping elements 15, heating elements 16, 16', and combined gripping and heating elements 16, 16' of a part 31 to be molded together with the first portion of the hollow body 10, regardless of whether it is at least one of the internal components 30. The gripping elements can be, for example, grippers 15a or suction elements. In the examples of Figures 13 and 14, the grippers 15a can be moved from an open position (Figure 13) to a closed position (Figure 14) by means of an actuator 15b to apply a parison 20 to the part 31, as described, for example, in EP 3946905. The heating element 16 in the example of Figure 15 is an electric heater 16a, and the heating element 16' in the example of Figure 16 is a hydroheater 16' for locally heating at least the parison 20. According to one example, the part 31 is a metal fastener or a fiber reinforcement.

[0092] In the example shown in Figure 12, at least one first section 3 of the mold 1 includes a blow tool 13 for injecting pressurized gas into the parison 20. As can be seen in Figure 12, the blow tool 13 includes a blow needle 13a that can penetrate the parison 20 to perform step d). It can also be seen that the blow needle 13a is movably attached to the first molding surface 11 by means of an actuator 13b for moving the blow needle 13a from a position retracted within the at least one first section 3 to a position protruding from the bottom of the first molding surface 11, and vice versa.

[0093] In the example shown in Figure 17, at least one first section 3 and / or second section 4 of part 1a of mould 1 comprises a cooling device 17 for cooling a region of hollow body 10. At least one first section 3a of mould 1 comprises a cooling element 17a for cooling a first region of hollow body 10. At least one second section 4a of mould 1 comprises a cooling element 17b for cooling a second region of hollow body 10. Of course, cooling elements 17a, 17b can be part of the same hydrocircuit of cooling device 17.

[0094] 8 to 10 show a second embodiment of the mold 1. The second embodiment differs from the first embodiment in that the second part 1b of the mold 1 forms an integral section 8. In other words, the integral section 8 of FIGS. 8 to 10 replaces at least one of the first section 3b and the second section 4b of the part 1b of the mold 1 compared to the first embodiment of FIGS. 5 to 7. This allows the number of parts required to construct the mold 1 to be reduced, thereby simplifying the mold 1.

[0095] 18 to 21 show a third embodiment of the mold 1. The third embodiment differs from the first embodiment in that the mold 1 is a mold for extrusion blow molding a hollow body 10 of a plastic "saddle tank" for an automobile from a parison 20.

[0096] The mold portion 1a includes at least one third section 18, 18a having a third molding surface 19, 19a for a third portion of the hollow body 10 to be produced. The third molding surface 19, 19a includes at least one secondary bearing area 5b. The at least one third section 18, 18a of the mold portion 1a moves relative to the at least one first section 3, 3a associated with the mold portion 1a between at least an intermediate position and a final position. In the final position, the at least one secondary bearing area 5b is configured to compress and reduce a predetermined volume within the parison 20.

[0097] 18-25, the third molding surface 19, 19a of the portion 1a of the mold 1 includes a plurality of secondary bearing regions 5b. In these examples, the first portion 1a of the mold 1 includes at least one first section 3a, a second section 4a, and at least one third section 18a, and the second portion 1b of the mold 1 includes the second section 4b and a single integral section that combines the at least one first section 3b and the at least one third section 18b.

[0098] Figures 18 to 21 also show a portion of a machine 100 for extrusion blow molding hollow bodies 10 of plastic automotive saddle tanks from parisons 20. The molding machine 100 includes a mold 1 based on the third embodiment introduced above. Figure 18 shows the mold 1 in an open position (open mold 1), Figure 19 shows the mold 1 in an intermediate closed position, and Figure 20 shows the mold 1 in a final closed position. Figure 20 also shows at least one third section 18 of part 1a of mold 1 in the intermediate position, and Figure 21 shows at least one third section 18 of part 1a of mold 1 in the final position.

[0099] In the example shown above, the second sections 4, 4a, 4b of the mold 1 surround at least one first section 3, 3a, 3b of the mold 1 in the final closed position of the parts 1a, 1b of the mold 1, and the at least one first section 3, 3a, 3b of the mold 1 surrounds at least one third section 18, 18a, 18b, so that the first molding surfaces 11, 11a, 11b, the second molding surfaces 12, 12a, 12b and the third molding surfaces 19, 19a, 19b together form the total molding surface, or cavity 2.

[0100] 18 to 21 also show a method for extrusion blow molding a hollow body 10 of a plastic saddle tank for an automobile using a parison 20, the saddle tank including at least one internal component 30 fixed inside the parison 20 during molding of the hollow body 10, the method preferably comprising the following steps performed consecutively: a) inserting at least one of the internal components 30 and a molten parison 20 into an open mold 1 consisting of two parts 1 a, 1 b such that the at least one internal component 30 is surrounded by the parison 20, wherein the at least one mold 1 part 1 a, 1 b includes at least one first section 3, second section 4 and at least one third section 18, which define therein a first molding surface 11, a second molding surface 12 and a third molding surface 19 of the overall molding surface of the mold 1, respectively; b) moving at least one first section 3 of the parts 1 a, 1 b of the mold 1 so that the mold 1 is in an intermediate closed position in which the at least one first section 3 presses the parison 20 against the at least one internal component 30 to fix the at least one internal component inside the parison, the first molding surface 11 being configured to simultaneously form a plurality of fixation zones of the at least one internal component 30 inside the parison 20 by compression; c) moving the second section 4 of the mould 1 relative to the first section 3 of at least one of the mould parts 1a, 1b so that the mould 1 is in a final closed position in which the two mould parts 1a, 1b are closed and define therein a total moulding surface which reproduces the predetermined shape of the hollow body 10 to be produced; d) moving at least one third section 18 of the mold 1 parts 1 a, 1 b relative to the at least one first section 3 of the mold parts 1 a, 1 b so that the at least one third section 18 is in a position where a third molding surface 19 presses the parison 20 to reduce a predetermined volume inside the parison 20; e) a step of blowing the parison 20 by pressing the parison 20 against the entire molding surface of the mold 1 using pressurized gas; f) opening the mold 1 to remove the produced hollow body 10; Includes.

[0101] Preferably, pressurized gas is injected into the parison 20 between steps a) and b) to pre-blow the parison 20. This type of gas injection can be performed according to step b) of Patent Document 1, particularly to expand the parison while maintaining a uniform thickness. Injecting gas at a lower pressure than in step e) can be performed by various methods known to those skilled in the art. As a non-limiting example, gas injection for pre-blow can be performed by a blowing tool used to perform step e), a dedicated tool attached to the mold, a hollow support rod of an internal component, or a nozzle included in the extrusion head of the parison.

[0102] Advantageously, in step b), said at least one internal component 30 is fixed inside the parison 20 by welding, riveting or mechanical fastening.

[0103] The blowing in step e) is carried out in the final closed position of the mould 1 at a blowing pressure of about 10 bar (1 MPa).

[0104] Preferably, at least one third section 18 of parts 1a, 1b of mold 1 is divided into a plurality of subsections that move relative to one another between intermediate and final positions, and the third molding surface 19 includes a plurality of secondary support areas 5b, each secondary support area 5b being supported by at least one subsection of the third section 18.

[0105] 22 to 25 show a fourth embodiment of the mold 1. The fourth embodiment differs from the third embodiment in that at least one third section 18, 18a of part 1a of the mold 1 is divided into a plurality of subsections that are separated from one another, and each secondary bearing area 5b is supported by a subsection of at least one third section 18, 18a of part 1a of the mold 1.

[0106] According to the invention, advantageously the subsections of at least one third section 18, 18a of part 1a of mould 1 are mutually movable between an intermediate position and a final position.

[0107] 26 and 27 show a fifth embodiment of the mold 1 in its final position. The fifth embodiment differs from the third embodiment in that the secondary support area 5b is configured to bring two opposing support areas of the parison 20 into contact with each other for local welding when the third sections 18, 18a, and 18b of the mold parts 1a and 1b are in their final positions. This local weld 22, sometimes referred to as a "kiss off" or "kiss point," can locally reinforce a hollow body, for example. More specifically, according to this particular embodiment, each mold part 1a and 1b includes at least one secondary support area 5b. The secondary support area 5b is configured to press the two opposing support areas of the parison 20 together for local welding when the third sections 18a and 18b of the mold parts 1a and 1b are in their final positions. In this way, local welds 22 can easily be formed, which can reinforce a hollow body, for example. It will be appreciated that the secondary bearing area 5b has a special shape that allows the two opposing bearing areas of the parison 20 to come into contact in order to allow for localized welding 22. This shape may vary depending on the embodiment, for example depending on the desired contact surface between the two opposing bearing areas of the parison 20.

[0108] 26 and 27 show cross sections through the local weld 22 of the mold 1 in its final position. In this case, it can be seen that the local weld 22 locally joins both walls of the parison 20 to form the top and bottom walls of the hollow body 10.

[0109] 27 also shows the internal component 30 to be fixed. In this example, the internal component 30 includes a fuel line 33 that connects two opposing parts of the internal component 30. Note that the fuel line 33 is not located in a cross section passing through the local weld 22, but in another plane parallel to this cross section.

[0110] The present invention is not limited to the illustrated embodiment and variations, and other embodiments and variations will be apparent to those skilled in the art. Thus, the above-described embodiments are exemplary. Although the specification refers to one or more embodiments, this does not necessarily mean that each reference numeral refers to the same embodiment or that each feature applies only to one embodiment. Individual features of various embodiments may be combined and / or interchanged to provide further embodiments. Without limitation, in the second embodiment, to further simplify the molding machine 100, it is also conceivable to use only one actuator 7 to move the second section 4a toward the integral section 8 (i.e., stationary). Similarly, although FIGS. 1 through 17 show only one first section 3a, 3b of the portions 1a, 1b of the mold 1, it is also conceivable that at least one first section 3a, 3b of the mold 1 includes multiple first sections 3a, 3b, e.g., 2, 3, 4, 5, 6, 7, 8, 9, or 10 first sections 3a, 3b. [Explanation of symbols]

[0111] 1. Mold 1a First part of the mold 1b Second part of the mold 2. Mold cavity 3, 3a, 3b First section of the mold 4, 4a, 4b Second section of the mold 5a Primary bearing area 5b Secondary bearing area 6 First Actuator 7 Second Actuator 8 integral sections 9 Support Plate 10 Hollow body 11, 11a, 11b First molding surface 12, 12a, 12b Second molding surface 13 Blowing Tools 13a Insufflation needle 13b Insufflation needle actuator 14 Suction element 14a Bottom suction element 14b suction element of primary bearing area 5a 14c Connection to suction device 15 Gripping elements 15a Gripper 15b Actuator 16, 16´ heating element 16a Electric heater 16b Hydro heater 17 Cooling device 17a Cooling element of first section 3a 17b Cooling element of second section 4a 18, 18a, 18b Third section of the mold 19, 19a, 19b third molding surface 20 parison 21 Moving parts of the parison bottom sealing device 22 Localized welding 30 Internal Components 31 parts 32 Internal component support rod 33 Fuel line 100 Extrusion Blow Molding Machine, Extrusion Blow Molding Machine

Claims

1. A mold (1) for extrusion blow molding a hollow body (10) of a plastic tank for an automobile from a parison (20), the tank including at least one internal component (30) fixed inside the parison (20) during molding of the hollow body (10), the mold (1) including two parts (1a, 1b) movable relative to each other, which, when closed to each other, define an entire molding surface therein for reproducing a predetermined shape of the hollow body (10) to be manufactured, and at least one of the parts (1a, 1b) of the mold (1) at least one first section (3, 3a, 3b) having a first moulding surface (11, 11a, 11b) of a first part of the hollow body (10) to be produced, said first moulding surface (11, 11a, 11b) including at least one primary bearing area (5a) adapted to form, by compression, a fixation zone for at least one internal component (30) inside the parison (20); a second section (4, 4a, 4b) having a second molding surface (12, 12a, 12b) of a second part of the hollow body (10) to be produced, the second section (4, 4a, 4b) of the part (1a, 1b) of the mould (1) moving relative to at least one first section (3, 3a, 3b) associated with the part (1a, 1b) of the mould (1) between at least an intermediate closing position and a final closing position of the part (1a, 1b) of the mould (1); at least one third section (18, 18a, 18b) having a third moulding surface (19, 19a, 19b) of a third part of the hollow body (10) to be produced, said third moulding surface (19, 19a, 19b) comprising at least one secondary bearing area (5b), said at least one third section (18, 18a, 18b) of said part (1a, 1b) of the mould (1) being movable relative to at least one first section (3, 3a, 3b) associated with said part (1a, 1b) of the mould (1) between at least an intermediate position and a final position in which said at least one secondary bearing area (5b) is configured to compressively reduce a predetermined volume inside the parison (20); Including the mold.

2. 2. The mold according to claim 1, wherein the first molding surface (11, 11a, 11b) of the part (1a, 1b) of the mold (1) is configured to extend along a circumscribing surface that includes the primary bearing area (5a) associated with the part (1a, 1b) of the mold (1).

3. 3. The mold according to claim 2, wherein the circumscribing surface of the first molding surface (11, 11a, 11b) of the part (1a, 1b) of the mold (1) includes a predetermined margin distance at least around the primary bearing area (5a) of at least one internal component (30) associated with the part (1a, 1b) of the mold (1) to suppress waviness of material around each fixation zone.

4. The mold of claim 3 , wherein the predetermined margin distance at least around the periphery of the fixation zone is between 1 mm and 60 mm.

5. 5. The mold according to claim 2, wherein the circumscribing surface of the first molding surface (11, 11a, 11b) of the at least one portion (1a, 1b) of the mold (1) is 15% or more of the total molding surface.

6. 6. A mold according to any one of claims 1 to 5, wherein the or at least one secondary bearing area (5b) is configured to bring two opposing bearing areas of the parison (20) into contact for local welding together when the third section (18, 18a, 18b) of the part (1a, 1b) of the mold (1) is in its final position.

7. 7. A mold according to any one of claims 1 to 6, wherein the third molding surface (19, 19a, 19b) of the part (1a, 1b) of the mold (1) comprises a plurality of secondary bearing areas (5b).

8. 8. The mold according to claim 7, wherein the third section (18, 18a, 18b) of at least one of the parts (1a, 1b) of the mold (1) is divided into a plurality of subsections separated from one another, and each secondary support area (5b) is supported by one subsection of the third section (18, 18a, 18b) of the part (1a, 1b) of the mold (1).

9. 9. A mold according to claim 8, wherein the subsections of the third section (18, 18a, 18b) of at least one of the parts (1a, 1b) of the mold (1) are mutually movable between the intermediate position and the final position.

10. 10. A mold according to any one of claims 1 to 9, wherein each part (1a, 1b) of the mold (1) comprises at least one first section (3, 3a, 3b), a second section (4, 4a, 4b) and at least one third section (18, 18a, 18b).

11. 11. The mold according to claim 10, wherein at least one of the first sections (3, 3a, 3b) of the mold (1) of each part (1a, 1b) of the mold (1) comprises at least one primary support area (5a) configured to press the parison (20) against the same at least one internal component (30) to form at least two different fixation zones of the same at least one internal component (30) for the purpose of fixing the same at least one internal component (30) inside the parison (20) during molding of the hollow body (10).

12. 10. The mold according to any one of claims 1 to 9, wherein only one of the portions (1a, 1b) of the mold (1) comprises at least one first section (3, 3a, 3b), second section (4, 4a, 4b) and at least one third section (18, 18a, 18b).

13. 13. A mold according to any one of claims 1 to 12, wherein at least one first section (3, 3a, 3b) of the mold of each part (1a, 1b) of the mold (1) is surrounded by a second section (4, 4a, 4b) associated with said part (1a, 1b) of the mold (1) in the final closed position.

14. 14. A mold according to any one of claims 1 to 13, wherein at least one third section (18, 18a, 18b) of the mold of each part (1a, 1b) of the mold (1) is surrounded by at least one first section (3, 3a, 3b) associated with said part (1a, 1b) of the mold (1) in the final closed position.

15. 15. The mold according to any one of claims 1 to 14, wherein at least one of the first sections (3, 3a, 3b) and / or third sections (18, 18a, 18b) of the parts (1a, 1b) of the mold (1) comprises a plurality of first sections (3, 3a, 3b) and / or third sections (18, 18a, 18b).

16. A machine for extrusion blow moulding hollow bodies (10) of plastic tanks for automobiles from parisons, characterized in that it comprises a mould (1) according to any one of claims 1 to 15.

17. A method for extrusion blow molding a hollow body (10) of a plastic tank for an automobile using a parison (20), the tank comprising at least one internal component (30) fixed inside the parison (20) during molding of the hollow body (10), the method comprising the following steps: a) inserting at least one of the internal components (30) and the molten parison (20) into an open mold (1) consisting of two parts (1 a, 1 b) such that the at least one internal component (30) is surrounded by the parison (20), wherein at least one of the parts (1 a, 1 b) of the mold (1) comprises at least one first section (3), a second section (4) and at least one third section (18) that define therein a first molding surface (11), a second molding surface (12) and a third molding surface (19) of the overall molding surface of the mold (1), respectively; b) moving at least one first section (3) of said parts (1 a, 1 b) of said mold (1) to an intermediate closed position in which said at least one first section (3) of said parts (1 a, 1 b) of said mold (1) presses said parison (20) against at least one internal component (30) to fix said at least one internal component (30) inside said parison (20), said first molding surface (11) being configured to form a plurality of fixation zones of said at least one internal component (30) inside said parison (20) by compression; c) moving the second section (4) of the parts (1a, 1b) of the mold (1) relative to the first section (3) of at least one of the parts (1a, 1b) of the mold (1) so that the mold (1) is in a final closed position in which the two parts (1a, 1b) of the mold (1) are closed and define therein the entire molding surface reproducing the predetermined shape of the hollow body (10) to be produced; d) moving at least one third section (18) of said part (1a, 1b) of said mould (1) relative to at least one first section (3) of said part (1a, 1b) of said mould (1) so that said at least one third section (18) is in a position where said third moulding surface (19) presses said parison (20) to reduce the predetermined volume inside said parison (20); e) blowing the parison (20) by pressing it against all molding surfaces of the mold (1) using pressurized gas; f) opening the mold (1) to remove the produced hollow body (10); A method comprising:

18. 18. The molding method according to claim 17, wherein pressurized gas is injected into the interior of the parison (20) to perform pre-blowing of the parison (20) between the steps a) and b).

19. 19. The molding method according to claim 17 or 18, wherein in step b) at least one of the internal components (30) is fixed inside the parison (20) by welding, riveting or mechanical fastening.

Images