Blow mould, box and use thereof and method for stretch blow moulding

Abstract

The invention relates to a device with which the production of plastic containers having a handle that can be clamped on by stretch blow molding can be improved. To this end, the invention provides, in one aspect, a box (100) for insertion into an opening (111; 127; 6) of a wall (5) of a blow mold part (3) of a blow mold (1), the box being used for stretch blow molding of PET containers having a handle holder for a handle that can be clamped therein, wherein the handle holder comprises at least one undercut in the plastic hollow body for accommodating a complementarily configured handle element, and wherein the box (100) comprises the following: - a box housing, - at least one opening arranged in the box housing (101) and capable of being opened through the box housing (101); A forming element (102) is guided forward from the box housing (101) through an opening (110, 127, 6) and can be guided back into the box housing (101) for forming the at least one undercut in the thermoplastically deformable wall material of the PET container, and at least one fluid cylinder (103, 131) is arranged in the box housing (101) and mechanically coupled to the at least one forming element (102), wherein the at least one forming element (102) can be at least partially guided forward from the box housing (101) and can be guided back into the box housing (101) by means of the fluid cylinder (103).

Description

Technical Field

[0001] The invention relates to a blow mould for stretch blow moulding of PET containers having a handle holder for a handle that can be clamped therein, and to a box for use in such a blow mould. The invention also relates to a method for producing a PET container having a handle that can be clamped therein. Background Art

[0002] It is known that in particular larger plastic containers, which are to be filled with liquids such as juice, water, sauces etc., are provided with handles for better handling. Various methods exist here in order to achieve a gripping possibility in plastic containers.

[0003] When stretch blow molding plastic containers made of thermoplastics, gripping openings can be produced, for example, by deforming the wall material of the bottle so that it forms a handle. EP 3 272 497 B1 describes, for example, a method in which two inserts, such as die blocks, arranged in recesses in the side walls of the blow mold can be moved radially into the interior of the blow mold and toward each other in order to produce an opening in the soft plastic material during the stretch blow molding process, which opening can be used as a handle. In the method described in EP 3 112 280 B1, in a similar manner, a portion of the soft bottle material is shaped during stretch blow molding by means of an insert that can be pushed into the blow mold so that a lateral handle is formed thereby.

[0004] JP2006-103003A describes a method in which a separate handle can be inserted into a blow mold by means of a gripping arm that can be inserted laterally through an opening in the blow mold wall so that the handle is molded into the bottle wall during stretch blow molding. Similarly, EP3124202A1 also discloses a blow mold for manufacturing a plastic container with a handle, in which a separate handle is introduced into the blow mold by means of two movable handle holders through an opening between two blow mold halves so that it can be molded onto the plastic container during stretch blow molding.

[0005] In addition, in order to manufacture plastic containers with handles by means of stretch blow molding, it is known that a bracket with an undercut or the like is formed in the wall material of the plastic container during stretch blow molding, and an external handle with a complementary shaped handle portion can be clamped into the bracket after the container is formed. In JPH11314268A, for example, a blow mold with an insert in its lateral wall is described. The insert protrudes into the interior of the blow mold so as to produce a groove in the plastic container formed by stretch blow molding, and the insert includes a lever with a protrusion, which can be pushed into the interior of the blow mold in a vertical direction toward the plastic container through an opening in the protruding part of the insert, so as to produce an undercut in the soft plastic material, and the handle can be subsequently clamped into the undercut. In WO95 / 15250, a blow mold is disclosed, which has an area of ​​the side wall protruding into the interior of the mold, wherein a dome can be pushed in the vertical direction in the area through the opening in the side wall, so as to construct an undercut in the plastic container that has not yet hardened, so as to install the handle later. Summary of the invention

[0006] The object of the present invention is to improve the production of plastic containers with grippable handles after stretch blow molding. In particular, the object of the present invention is to provide a device that makes the production of such plastic containers less prone to disruption and easier to maintain, in order to avoid longer production interruptions.

[0007] In a first aspect, the object is achieved by a box for insertion into an opening in a wall of a blow mold part of a blow mold, the box being used for stretch blow molding of PET containers having a handle holder for a handle that can be clamped therein, wherein the handle holder comprises at least one undercut in the plastic hollow body for accommodating a complementarily configured handle element, and wherein the box comprises the following:

[0008] - box housing,

[0009] at least one shaping element which is arranged in the box housing and can be guided forward from the box housing through an opening in the box housing and can be guided back into the box housing for shaping the at least one undercut in the thermoplastically deformable wall material of the PET container, and

[0010] at least one fluid cylinder, which is arranged in the cartridge housing and is mechanically coupled to the at least one forming element,

[0011] Therein, the at least one shaping element can be guided at least partially forward from the cassette housing by means of the fluid cylinder and can be guided back into the cassette housing.

[0012] A "box" is understood here to be a container which is preferably closed on all sides. The term "closed on all sides" means that there are lateral, upper and lower as well as front and rear container walls which enclose the container interior, but does not exclude the possibility that one or more openings may be present in one or more walls. The term "box module" is used here synonymously with the term "box" if necessary.

[0013] A "blow mold" is understood to be a mold for producing a plastic hollow body by means of blow molding. In the stretch blow molding of such PET containers, for example plastic bottles, a preform is heated, for example, by means of an IR heat radiator and introduced into a hollow mold, the inner wall of which surrounds a cavity, which has the outer shape of the PET container to be formed. The inner wall of the hollow mold predetermines the contour of the wall of the PET container to be formed. The heated preform, which is thermoplastically deformable in this way, is expanded, for example, by means of a gas, for example air, introduced into the preform, until it rests against the inner wall of the blow mold and has its contour. The plastic hollow body formed in this way can then be removed from the mold and fed to other processes. Such a blow mold can include, for example, two or more blow mold parts, for example, lateral mold halves of two half shells and a bottom mold part.

[0014] When referring to a "radial direction" herein, unless the context indicates otherwise, this refers to a direction perpendicular to the longitudinal axis of the blow mold. For example, in the case of a generally cylindrical blow mold, the longitudinal axis means the axis of rotation.

[0015] A "preform" is a preform made of thermoplastic for subsequent blow molding, which can be produced by injection molding. For example, it can be a hollow body made of polyethylene naphthalate (PET), which is usually cylindrical with a bottom and an opposing bottle thread. The preform is first heated to a suitable processing temperature so that the plastic transitions to a viscous state and during the subsequent blow molding is formed, i.e. inflated, into the final product, for example a bottle, by means of a shaped blow mold so that it fits onto the contour of the blow mold.

[0016] A “PET container” is understood here to be a hollow body which is lined or provided with a plastic wall made of polyethylene terephthalate (PET), for example a bottle for liquids, such as juice, water, sauces, etc. PET is a thermoplastic.

[0017] A "handle support" is understood here to be a part or region of a PET container which is designed to accommodate a handle. For example, it can be a region in the side wall of the PET container which is provided with an undercut, with which the handle can engage with a complementary handle element, for example a correspondingly designed projection. The handle support can also include, for example, a groove-like recess in the side wall which has an undercut.

[0018] The term "undercut" is used here to refer to a recess, notch, groove, recess, depression, etc. in the wall of a PET container, which can engage with a complementary element of the handle, such as a projection. The above terms are used here synonymously.

[0019] When the term "complementary" is used herein in relation to elements of the blow mould, the box or the PET container to be produced, this refers to the respective elements having a spatial-volume relationship with one another in which the first element has a "positive" characteristic value and the complementary element has a "negative" characteristic value, or vice versa. For example, the blow mould can have an internal contour that is complementary to the container surface, i.e., an internal (negative) contour that corresponds to the (positive) contour of the wall of the container to be formed by means of the blow mould.

[0020] The expression "clampable" about the handle means that the handle can be connected to the handle support of the plastic body by means of a positive locking snap connection. For this purpose, the handle has, for example, a handle element, such as a projection, which can engage with the undercut of the handle support.

[0021] A "forming element" is understood here to mean an element by which an undercut can be mechanically formed into the wall of the PET container by the element being pushed onto the heated and thereby plastically deformable wall and the wall being pressed in, wherein the soft wall material at least partially surrounds the forming element. If necessary, the terms "slider element" or "embossing element" are also used here synonymously for the forming element.

[0022] The statement that the forming element is "at least partially guided forward from the box housing into the box housing and can be guided back" means that the forming element can be guided forward from the box housing into the box housing and can be guided back with at least a part of it, such as an end section, a protrusion, a leg, etc.

[0023] A "fluid cylinder" is understood here to be a fluid-based drive element for linear motion. A fluid cylinder comprises a piston, the movement of which is transmitted to the component to be moved via a piston rod. The piston is moved by means of a fluid, which can be a gas or a liquid. The term "hydraulic cylinder" includes the terms "pneumatic cylinder" and "hydraulic cylinder". The expression "fluidically actuated" means the actuation of the fluid cylinder by means of a fluid, for example pneumatically or hydraulically.

[0024] The expression that the at least one forming element is mechanically coupled to the at least one fluid cylinder means that the at least one forming element is mechanically coupled to the at least one fluid cylinder in such a way that when the fluid cylinder is actuated, the forming element is also actuated, that is to say the at least one forming element or a part thereof is guided forward from the cartridge housing into the cartridge housing or guided back. The mechanical coupling can be realized, for example, by means of a connecting member that can be rotatably supported on a shaft.

[0025] The statement that the box is "detachably arranged" in an opening in the wall of one of the blow mold parts means that the box is arranged so that it can be removed from the opening without destruction. This includes fixing the box in the opening, for example by means of a screw connection or in another suitable manner, so as to prevent the box from accidentally moving or coming loose from the opening during the use of the blow mold as required. The statement that the box "closes the opening" means that the box fills the opening in the installed state at least in the axial direction and the circumferential direction with respect to the blow mold. For this purpose, the box housing is dimensioned so that the box housing rests on the soffit of the opening with its side walls all around. Preferably, the box also fills the opening in the radial direction of the blow mold.

[0026] Box according to the present invention (which is also referred to as "slider box" when necessary, because it includes at least one forming element, which can be pushed into the wall material of the plastic container that is thermoplastically deformable by heating) includes at least one forming element arranged therein, which can be at least partially guided forward from the box housing into the box housing and guided back, so as to form an undercut in the thermoplastically deformable wall material of the PET container. If there are multiple forming elements, these forming elements can be constructed identically, so that they are symmetrically arranged in the box housing. This reduces the number of required components, thereby making manufacturing costs more favorable. In addition, at least one fluid cylinder is arranged in the box housing, which is mechanically coupled with the forming element, and the forming element can be manipulated by means of the fluid cylinder, that is to say, can be guided forward and guided back. The box contains the mechanical components required for manipulating the forming element, and can therefore be replaced, for example, in a modular manner. It is thus possible, for example, to simply replace the components provided for forming an undercut in a plastic body, for example, in the case of a fault or for other geometric structures of a handle support and / or an undercut that should be realized. Simple removal or replacement of the cartridge also facilitates maintenance of the blow mould designed to house the cartridge according to the invention.

[0027] In a particularly preferred embodiment, in the installed state, the box according to the present invention has at least one opening for connecting a fluid line oriented toward the wall of the blow mold part for fluidly manipulating the at least one fluid cylinder. For example, it can involve an opening arranged laterally on the box housing. In the case of a single-acting fluid cylinder, the opening is sufficient to provide two openings in the case of a double-acting cylinder, through which fluid can be conveyed. In the case of a preferred design with two double-acting fluid cylinders, the double-acting fluid cylinders are mechanically coupled to the forming element, preferably with four openings for the fluid supply of the two fluid cylinders, wherein two openings can be provided on the housing side and two openings can be provided on the opposite housing side. In this design, the one or more fluid cylinders can be advantageously supplied with fluid and manipulated via the fluid line in the blow mold wall. Therefore, the box module can be replaced in a simple manner with another box module equipped with a corresponding fluid interface without having to remove the fluid supply line before.

[0028] In a preferred design, the box is dimensioned so that the box does not extend beyond the outer surface of the wall of the blow mold part when it is mounted with the box housing. The outer surface is also referred to as "the surface of the back side of the blow mold wall" or "the back side of the blow mold part" when necessary. The outer surface of the wall of the blow mold part refers to that surface of the blow mold part that faces away from the cavity of the blow mold, that is, the surface of the wall of the blow mold part that is located outside, which is opposite to the surface of the contour of the blow mold part facing the inner cavity and pre-given the plastic container. Here, the face pointing to the cavity is called the inner surface of the blow mold part, which contacts its outer wall when the PET container is formed. In the embodiment, the box is designed so that it, for example, does not extend beyond the back side of the blow mold part relative to the blow mold in the radial direction in the case of a generally cylindrical blow mold.

[0029] Preferably, the box is fully integrated into the wall of the blow mold, and the face of the back side of the box housing is preferably aligned with the face of the back side of the blow mold wall. Here, the box housing can be designed so that it makes the outer peripheral wall surface of the blow mold complete with its rear wall in the installed state, for the maximum container shape provided in the region of the opening. Here, the blow mold provided for smaller containers has the same size as the blow mold for the container provided with the maximum. Therefore, the box is arranged deeper in the blow mold in this case and no longer aligned with the outer peripheral wall surface of the blow mold. In addition, in the blow mold of smaller containers, the box can be moved closer to the bottleneck. The usability of the box for the container of multiple sizes has the advantage that the same components can be used for the box of these container sizes, and these components are cheaper in manufacturing thus. In addition, this has the advantage that many replacement boxes from other blow molds are available when a malfunction occurs. Therefore, even when a plurality of boxes malfunction, because it is not necessary to manufacture or provide spare boxes immediately, production interruption is avoided.

[0030] For example, in the case of a generally cylindrical blow mold, the rear wall of the box is preferably curved in a circular arc in cross section so that it completes the concrete outer wall of the blow mold in the opening area of ​​the blow mold accordingly. In the preferred embodiment, the box is dimensioned and designed so that the box closes the opening so that the back side of the box becomes part of the outer surface of the blow mold part for the container of the maximum setting. Other designs are also possible, such as a rear wall that is not curved and configured flatly.

[0031] In a preferred embodiment of the cassette according to the invention, the at least one fluid cylinder is a pneumatic cylinder and the at least one shaped element is pneumatically actuatable, ie can be guided forwards from the cassette housing into the cassette housing and back.

[0032] In a preferred embodiment of the box according to the invention, the box housing has a rear base part and a front part protruding relative to the base part, wherein the front part or at least one of its regions preferably has an outer contour complementary to the contour of at least a part of the handle support, and wherein the front part has at least one opening, through which the at least one forming element can be guided forward from the box housing into the box housing and guided back. In the embodiment, the box housing can be arranged in the wall of the blow mold part with its rear base part in the installed state and fixed to the wall of the blow mold molded part by means of corresponding fixing devices (e.g., screw connections) as necessary, while the front part protruding relative to the base part at least protrudes into the cavity of the blow mold with a part. The front part protruding into the cavity of the blow mold is used to mold the handle support or the area with a handle arranged thereafter in the plastic hollow body to be molded, such as a groove in the wall of a PET container. The front part can also include ribs that further protrude in the direction of the cavity relative to its front side pointing toward the cavity of the blow mold. In the front part, the box housing has at least one opening, through which the shaped element or a part thereof can be guided forward and back by means of the at least one fluid cylinder, for example a pneumatic cylinder. Preferably, at least two openings are arranged in the front part, through which a respective shaped element or a part thereof can be guided forward and back by means of a fluid cylinder, for example a pneumatic cylinder. The openings are preferably spaced apart from one another in the axial direction relative to the blow mold and are preferably also open in the axial direction, so that when the fluid cylinder is actuated, the shaped element or a part thereof is pushed into the cavity in the axial direction.

[0033] In a preferred embodiment, the box comprises two forming elements and two fluid cylinders, wherein each fluid cylinder is mechanically connected to only one associated forming element. Thus, each forming element is assigned a fluid cylinder.

[0034] In one embodiment of the box according to the invention, (a) the two forming elements can be arranged in a common second plane of the box housing in a mirror-symmetrical manner with respect to the first plane and spaced apart from each other in a direction perpendicular to the first plane, and / or (b) the two fluid cylinders are arranged with their longitudinal axes at an angle to the respectively associated forming elements and with their longitudinal axes crossing each other. In addition, the fluid cylinders can be arranged spaced apart from each other in a direction perpendicular to the second plane. In this way, a particularly compact design can be achieved with good force transmission, which makes it possible to fully accommodate the mechanical components for forming the undercut into the box housing and at the same time achieve the required path length for the forming elements in the direction of the cavity.

[0035] In a further embodiment, the two shaped elements can each be guided from the cassette housing forward into the cassette housing and back in different, preferably mutually opposite directions.

[0036] In another embodiment, the fluid cylinders can each have a rear wall for connection to a fluid line, wherein the rear wall has an angle between 90° and 0°, preferably between 80° and 10°, further preferably between 70° and 20°, further preferably between 60° and 30°, further preferably between 50° and 40°, and most preferably 45°.

[0037] In a further aspect, the invention provides a blow mold for stretch blow molding of PET containers having a handle holder for a handle that can be clamped therein, wherein the handle holder comprises at least one undercut in the plastic hollow body for accommodating a complementarily configured handle element, the blow mold comprising:

[0038] a) at least two blow mould parts which, close to one another, form a cavity having the outer shape of the PET container to be formed, wherein the wall of at least one of the two blow mould parts has an opening, and

[0039] b) A box according to the above-mentioned first aspect of the invention that is detachably arranged in the opening and closes the opening.

[0040] In a particularly preferred embodiment of the blow mold according to the present invention, the box does not extend out relative to the external face of the wall of the blow mold in the direction away from the cavity of the blow mold. In the embodiment, the box is dimensioned so that the box does not extend beyond the wall of the blow mold. The box is preferably fully integrated into the wall of the blow mold. In addition, the face of the back side of the box housing can preferably be aligned with the face of the back side of the blow mold wall. It is preferred that the box housing is designed so that it completes the peripheral wall surface of the outside of the blow mold with its rear wall in the region of the opening in the installed state. For example, in the case of a generally cylindrical blow mold, the rear wall of the box is preferably constructed in a circular arc shape in the cross section so that it completes the external face of the blow mold part according to the cylindrical shape. In the preferred embodiment, the box is dimensioned and designed so that the box closes the opening so that the face of the back side of the box completes the external face of the blow mold part in the region of the opening.

[0041] In another example, the box can be embedded in the wall. In this case, the box is further arranged inside the blow mold. This can occur, for example, when the box is used to form a handle on a container used on the same device as a larger container. The outer dimensions of the blow mold are the same for large and small containers. Correspondingly, the smaller container is arranged deeper in the blow mold, so that the box must therefore be positioned deeper in the blow mold in order to be able to mold a handle holder on the container.

[0042] In another aspect, the invention relates to a method for stretch blow molding a PET container in a blow molding mold, the PET container having a handle holder for a clampable handle according to stretch blow molding, wherein the handle holder comprises at least one undercut in a plastic hollow body for accommodating a complementarily constructed handle element, the method comprising the steps of: a) introducing a preheated preform made of thermoplastic plastic material into the blow molding mold according to the invention, and b) stretch blow molding the preform with the aid of the box construction undercut.

[0043] In the method according to the invention, a preform heated to a temperature suitable for stretch blow molding in a suitable manner known to a person skilled in the art is introduced into a blow mold according to the invention. The preform is formed into a plastic hollow body with a contour predetermined by the blow mold by means of stretch blow molding. In the still soft plastic of a PET container, such as a PET bottle, an undercut is introduced into the handle holder of the PET container or the area of ​​the wall surrounding the handle holder by means of a box. After the PET container is removed from the mold, the handle can be clamped into the undercut of the handle holder by means of a complementary gripping element.

[0044] In yet another aspect, the invention relates to the use of a blow mould according to the invention or a box according to the invention for producing a PET container with a handle holder for a clampable handle. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The invention is explained in more detail below with reference to exemplary drawings, purely for illustrative purposes.

[0046] Figure 1 A schematic sectional view of a part of an embodiment of a blow mould according to the invention is shown with an inserted cartridge according to the invention.

[0047] Figure 2 Shown in Figure 1 Simplified schematic cross-sectional view of a blow mould shown in , with an inserted cassette.

[0048] Figure 3A spatial view from the side, viewed from the front, of one embodiment of a cassette according to the invention is shown.

[0049] Figure 4 The box according to the present invention is shown in Figure 3 A top view of the embodiment shown in FIG.

[0050] Figure 5 The box according to the invention is shown in the case where the housing halves are omitted. Figure 3 A side view of the embodiment shown in FIG.

[0051] Figure 6 The box according to the invention is shown in the case where the housing halves are omitted. Figure 3 A spatial view of the embodiment shown in FIG. 1 , viewed laterally from the front.

[0052] Figure 7 The box according to the present invention is shown in Figure 3 A side view of a portion of the embodiment shown in FIG.

[0053] Figure 8 The box according to the present invention is shown in Figure 7 A spatial view of the part shown in FIG. 1 , viewed laterally from the front. DETAILED DESCRIPTION

[0054] exist Figure 1, a simplified schematic cross-sectional view of a portion of an embodiment of a blow mold 1 according to the invention is shown with an inserted box 100 according to the invention. A longitudinal section of a generally cylindrical blow mold 1 with blow mold parts 2, 3, which are close to each other to form a cavity 4, wherein parts of the inner faces of the blow mold parts 2, 3 that are not in the section plane are also shown together for better illustration. The contour of the inner face 7 of the wall 5 of the blow mold part 2, 3 is designed to complement the contour of the PET container formed by means of the blow mold 1. An opening 6 is arranged in one of the blow mold parts 2, 3, into which the box 100 according to the invention (optionally also referred to as a slider box) is removably inserted. The box 100 comprises a box housing 101, the rear wall 114 of which is aligned with the outer face 8 of the blow mold part 3 with its outer face 115. Therefore, the box housing 101 of the box 100 does not protrude beyond the outer face 8 of the blow mold wall 5 in the radial direction. Box housing 101 comprises a basic part 113 and a front part 112 pointing to the cavity 4, and box housing 101 is with this front part relative to the basic part 113 and protrudes into the cavity 4. The profile of the front part 112 is designed so that the handle support can be formed in the plastic hollow body to be formed. Two forming elements 102 and two fluid cylinders 103 are arranged in the box housing 101, and they are configured as pneumatic cylinders at this. Each forming element 102 is assigned to a fluid cylinder 103. In this diagram, only one fluid cylinder 103 is visible. Forming element 102 is generally designed in L shape at this and is rotatably supported on the first shaft 107 in the region of the basic part 113. In the region of the front part 112, forming element 102 is respectively supported on the second shaft 108 and mechanically coupled with the piston rod 122 of the corresponding fluid cylinder 103 by connecting member 110, and the connecting member is rotatably supported on the second shaft 108 and on the shaft 109 connected with the piston rod 122 of the fluid cylinder 103. When the fluid cylinder 103 is actuated, the linear movement of the piston 123 is converted into a rotational movement of the forming element 102 via the piston rod 122 and the connecting element 110. The forming element 102 is generally constructed in an L-shaped or hook-shaped manner in this embodiment of the box 100 according to the invention. The legs 106 of the forming element 102 are arranged in the area of ​​the opening 111 in the front part 112 of the box housing 101 and are guided forward from the opening 111 in the direction of the cavity 4 or guided back in the direction of the box housing when the fluid cylinder 103 is actuated. In the case of a double-acting fluid cylinder 103, the forming element 102 can be pushed in and pulled back with the aid of the fluid cylinder 103 with its legs 106. In the case of a single-acting fluid cylinder 103, for example, a spring mechanism can be provided, which pushes the forming element 102 in and out of the housing. An embodiment with a double-acting fluid cylinder 103 is preferred. In Figure 1In the embodiment shown here, the legs 106 of the forming element 102 are pushed forward from the opening 111 in the direction of the cavity 4. In the embodiment of the blow mold 1 according to the invention, the two forming elements 102 are arranged in a common plane in a mirror-symmetrical manner along the axial direction of the blow mold 1. The opening 111 points to the cavity 4 in the axial direction in the protruding front part 112 of the box housing 101. When the forming element 103 is manipulated, the legs 106 are also pushed forward from the box housing 101 through the opening 111 in the axial direction and pulled back again. In the embodiment shown here, the opening 104 for approaching the forming element 102 and the opening 120 for accessing the fluid cylinder 103 or the threaded connection for the fluid cylinder 131 are provided in the rear wall 114 of the box housing 101, which are basically used for maintenance purposes.

[0055] Figure 2 1 shows a simplified schematic cross-sectional view of an embodiment of a blow mould 1 according to the invention. The blow mould parts 2, 3 are shown here only schematically. Figure 2 It can be seen that the rear wall 114 is curved so that it matches the outer shape of the blow mold 1. The rear wall 114 of the box 100 is a circular arc in cross section, which corresponds to the circular arc of the blow mold part 3 that is not otherwise semicircular in the region of the opening 6. Here, the front part 112 of the box 100 that protrudes relative to the base part 113 has a central rib 118 that extends in the axial direction relative to the blow mold 1, which further protrudes into the cavity 4 and serves to form a region of the PET container that serves to accommodate the base of the handle to be clamped.

[0056] Figure 3 A spatial view of an embodiment of a box 100 according to the invention, viewed from the front and sideways, is shown. "Front" here means the part of the box 100 that points toward the cavity 4 of the blow mold 1 in the installed state. The box housing 101 here comprises two housing halves 125, 126, which are connected to each other by means of a threaded connection 121. The box housing 101 can be made of metal or a suitable plastic, for example. In the side wall 119 of the box 100, openings 116, 117 are provided for connecting to a fluid line (for example a pneumatic line) in the wall 5 of the blow mold 1. Here, two openings 116, 117 for the double-acting fluid cylinder 103 are respectively provided. Two other openings 116, 117 are located on the opposite side wall 119 (see FIG. 1 ) which is not visible here. Figure 4 ). At least one further opening 127 is used to connect the box 100 to the blow mould 1. Here, the connection can be achieved by means of a cylindrical bolt. Thus, during the forming process of the container in the blow mould 1, the box 100 is fixed to resist the pressure applied thereto.

[0057] The basic part 113 of the box 100 is generally square here, and the front part 112 protruding relative to the basic part 113 is generally prismatic, wherein the basic part of the front part 112 is smaller than the basic part 113 in the axial direction. The front part 112 is arranged on the basic part 113 in the center. The front angle and edge of the box housing 101 are rounded. A protruding rib 118 is arranged in the center of the front face of the front part 112, which is suitable for forming a cavity in the plastic hollow body to be formed, and the cavity accommodates the base of the handle to be clamped. The legs 106 of the forming element 102 can be guided forward and guided back from the box housing 101 through the opening 111, which are arranged in the central rib 118 and point to the cavity 4 of the blow mold 1 in the axial direction in the installed state. The legs 106 shown here as the advanced state extend substantially parallel to the rear wall 114 and therefore extend relative to the blow mold 1 in the axial direction in the installed state.

[0058] exist Figure 3 The embodiment of the box 100 according to the present invention shown in Figure 4 Here, openings 116 , 117 for connection to fluid lines in the blow mold wall 5 , which are provided in the two side walls 119 of the box 100 and through which the two fluid cylinders 103 can be fluidically actuated, can be seen.

[0059] The arched rear wall 114 of the box 100 is also visible here. In the installed state, the contour of the rear wall 114 thus follows the contour of the outer face 8 of the wall 5 of the blow mold 1. In addition, in the installed state, the contour does not protrude relative to the outer face 8 of the wall 5 of the blow mold 1.

[0060] Figure 5 and Figure 6 A diagram is shown in Figure 3 An embodiment of a cassette 100 according to the invention is shown in , with the mold halves 125 , 126 removed for a better overview. Figure 5 Showing a side view, Figure 6 Shown is a spatial view observed from the front side. It can be clearly seen here how each fluid cylinder 103 is mechanically coupled to the forming element 102, and the mechanical components for operating the forming element 102, that is, the combination of the fluid cylinder 103, the forming element 102 and the coupling element for mechanically coupling the fluid cylinder 103 and the forming element 102 is completely placed in the box housing 101. Here, the hole 129 as part of the fluid delivery for advancing the piston 123 of the double-acting fluid cylinder 103 and the threaded connection 131 of the fluid cylinder can also be seen. The connecting element 110 is molded on the sleeve 130, which is rotatably supported concentrically on the shaft 109 connected to the piston rod 122.

[0061] For a better overview, Figure 7 and Figure 8 Only shown in Figure 3 1 is an embodiment of a box 100 according to the present invention shown in the figure, for manipulating the arrangement of mechanical elements of the forming element 102. In the embodiment shown here, the two forming elements 102 are arranged mirror-symmetrically with respect to a first plane, and are arranged in a common second plane spaced apart from each other in a direction perpendicular to the first plane. However, this is optional, so that in other embodiments the forming elements 102 are not arranged mirror-symmetrically.

[0062] The two fluid cylinders 103 are arranged with their longitudinal axes at an angle and cross each other relative to the respective forming elements 102. The fluid cylinders can further be optionally arranged spaced apart from each other in a direction perpendicular to the second plane. In the installed state, the forming elements 102 are stacked in the axial direction of the blow mold, wherein the legs 106 of the forming elements 102 extend in opposite directions in the axial direction. With respect to the plastic hollow body to be formed, such as a bottle, the forming element 102 forms an upper and lower undercut in the cavity formed by the front part 112 of the box 100 in the wall of the PET container, in particular, and a handle with a correspondingly complementary protrusion can be clamped into the upper and lower undercut. Here, the fluid cylinders 103 are arranged on both sides of the plane where the forming elements 102 are arranged, so that the forming elements 102 are located between the fluid cylinders 103. The fluid cylinders 103 are arranged so that their longitudinal axes intersect or extend at an angle to each other in a side view. Thus, with respect to the cartridge housing 101, the piston 123 of the first fluid cylinder 103 is arranged in a part of the base part 113, while the piston 123 of the second fluid cylinder 103 is arranged in the opposite part, which is relative to the installation state in the blow mold 1, for example, in the upper part and the lower part of the base part 113. Here, the fluid cylinder 103 (whose piston 123 is arranged in the upper part of the base part 113) is mechanically coupled with the lower forming element 102 by its piston rod 122, and the fluid cylinder 103 (whose piston 123 is arranged in the lower part of the base part 113) is mechanically coupled with the upper forming element 102 by its piston rod 122. This arrangement enables a compact structural mode of the cartridge 100. At the same time, the distance required for being able to form a sufficient undercut in the plastic hollow body can be achieved.

Claims

1. A box (100) for a blow mould (1), which is inserted into an opening (6) in a wall (5) of a blow mould part (2, 3) of the blow mould (1), for stretch blow moulding PET containers having a handle holder for a handle which can be clamped therein, wherein: The handle holder comprises at least one undercut in the plastic hollow body for accommodating a complementarily configured handle element, and wherein the box (100) comprises the following: - a box housing (101), at least one shaping element (102) which is arranged in the box housing (101) and can be guided forward from the box housing (101) through an opening (110) in the box housing (101) and can be guided back into the box housing (101) for shaping the at least one undercut in the thermoplastically deformable wall material of the PET container, and - at least one fluid cylinder (103) arranged in the box housing (101) and mechanically coupled to the at least one forming element (102), wherein the at least one forming element (102) can be at least partially guided forward from the box housing (101) and can be guided back into the box housing by means of the fluid cylinder (103), wherein the box (100) comprises two forming elements (102) and two fluid cylinders (103), wherein each fluid cylinder (103) is mechanically connected to only one of its respective forming elements (102), and wherein the two fluid cylinders (103) are arranged with their longitudinal axes at an angle to the respective forming elements (102) and with their longitudinal axes intersecting each other.

2. The box (100) according to claim 1, wherein In the installed state, the cassette (100) has at least one opening (116, 117) oriented toward the wall of the blow mold part (2, 3) for connecting a fluid line for fluidically actuating the at least one fluid cylinder (103).

3. The box (100) according to claim 1 or 2, wherein: The box (100) is dimensioned in such a way that, when mounted with the box housing (101), it does not project beyond the outer surface (8) of the wall (5) of the blow mold parts (2, 3).

4. The box (100) according to claim 1 or 2, wherein: The fluid cylinder (103) is a pneumatic cylinder and the at least one forming element (102) can be pneumatically guided forwards and back.

5. The box (100) according to claim 1 or 2, wherein: The box housing (101) has a rear base part (113) and a front part (112) protruding relative to the base part (113), the front part (112) or a region thereof having an outer contour complementary to the contour of at least a part of the handle support, and the front part (112) having at least one opening (111), and the at least one forming element (102) can be guided forward from the box housing (101) into the box housing (101) and guided back through the opening (111) of the front part (112).

6. The box (100) according to claim 1 or 2, wherein: The two shaped elements (102) can each be guided forward from the cassette housing (101) into the cassette housing (101) and back in different directions.

7. The box (100) according to claim 6, wherein The two shaped elements (102) can be guided forward from the cassette housing (101) into the cassette housing (101) and back in opposite directions.

8. The box (100) according to claim 1 or 2, wherein: The fluid cylinders (103) each have a rear wall for connecting to a fluid line, wherein the rear wall has an angle between 90° and 0°.

9. The box (100) according to claim 1 or 2, wherein: The fluid cylinders (103) each have a rear wall for connection to a fluid line, wherein the rear wall has an angle between 80° and 10°.

10. The box (100) according to claim 1 or 2, wherein: The fluid cylinders (103) each have a rear wall for connection to a fluid line, wherein the rear wall has an angle between 70° and 20°.

11. The box (100) according to claim 1 or 2, wherein: The fluid cylinders (103) each have a rear wall for connecting to a fluid pipeline, wherein the rear wall has an angle of 60° to 30°.

12. The box (100) according to claim 1 or 2, wherein: The fluid cylinders (103) each have a rear wall for connecting to a fluid line, wherein the rear wall has an angle between 50° and 40°.

13. The box (100) according to claim 1 or 2, wherein: The fluid cylinders (103) each have a rear wall for connecting to a fluid pipeline, wherein the rear wall has an angle of 45°.

14. A blow mould (1) for the stretch blow moulding of PET containers, the PET containers having a handle holder for a handle which can be clamped therein, wherein: The handle holder comprises at least one undercut in the plastic hollow body for accommodating a complementarily configured handle element, the blow mold comprising: a) at least two blow mould parts (2, 3) which, close to one another, form a cavity (4) having the outer shape of the PET container to be formed, wherein the wall (5) of at least one of the two blow mould parts (2, 3) has an opening (6), and b) Cassette (100) according to any of the preceding claims, wherein the cassette (100) is detachably arranged in an opening (6) of a wall (5) and closes the opening (6) of the wall (5).

15. The blow mould (1) according to claim 14, wherein The box (100) does not protrude relative to the outer surface (8) of the wall (5) of the blow mould part (2, 3) in a direction facing away from the cavity (4).

16. The blow mould (1) according to claim 14 or 15, wherein: The at least one fluid cylinder (103) is connected to a fluid line in the wall of the blow mould part (2, 3).

17. The blow mould (1) according to claim 14 or 15, wherein: The box (100) protrudes into the cavity (4) with a front part (112), and there is at least one opening (111) leading to the cavity (4) in the front part (112), and the at least one forming element (102) can be guided forward and back in the direction of the cavity (4) through the opening (111) of the front part (112).

18. A method for stretch blow moulding a PET container having a handle holder for a handle which can be clamped therein, wherein: The handle holder comprises at least one undercut in the PET container for accommodating a complementarily constructed handle element, the method comprising the steps of: a) introducing a preheated preform made of a thermoplastic plastic material into a blow mold (1) according to any one of claims 14 to 17, and b) stretch blow molding the preform while constructing the undercut with the aid of the box (100).

19. Use of a blow mould (1) according to any one of claims 14 to 17 or a cartridge (100) according to any one of claims 1 to 13 for producing a PET container having a handle holder for a clampable handle.

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