Apparatus for blow molding containers

Abstract

To provide an apparatus (1) for blow molding a container, provided with a support frame (2) for a station (3) that blow-molds a preform to obtain the container.SOLUTION: A blow molding station includes two lateral bodies (3a, 3b) and a bottom (3c). The lateral body is movable with respect to a support frame and is provided with means (60) for cyclically determining a movement of the bottom. The cyclic opening / closing means includes an actuation body (20) supported by a connecting link mechanism (11), the connecting link mechanism is kinematically connected to the movable lateral body and connected by a connecting assembly (50) to a movable undulating body (12), the undulating body defines a cam-shaped profile (13) that is engaged by an engagement element (14) supported by the bottom, the connecting assembly includes an actuating attachment (51), the actuating attachment supports a tangent body (52), and a sliding seat is incident to a travel track and extended along a sliding direction (104).SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to an apparatus for blow molding containers made of plastic, particularly those made of PET, PE, PEN, and similar materials.

Background Art

[0002] Plants for blow molding plastic containers are known, and these plants include an apparatus for blow molding preforms having a blow molding station disposed on a rotating advance wheel and a mold support hinged along one edge.

[0003] Apparatuses in which the blow molding station is fixed (particularly suitable for accommodating cavities for forming containers) are also known, and in this case, as the mold support, plates arranged parallel to each other are usually used.

[0004] The execution of operations for opening and closing the blow molding station and the execution of operations for lifting the base (or bottom) are usually mechanically actuated.

[0005] In a blow molding station disposed on a rotating advance wheel, a curved segment (cam) is particularly used, arranged to be fixed on the frame of the machine, and a cam follower is connected to an element driven and moved along the segment.

[0006] WO2007 / 012309 describes a blow molding station in which the base is moved longitudinally relative to the blow molding station, one mold support is fixed, and the other mold support is movable.

[0007] FR2841495, instead, describes a mold having a base that can move axially relative to a lateral support of the mold.

[0008] WO2006 / 029585 describes a blow molding station in which a mechanical bond is provided between the lateral support and base of the mold.

[0009] To achieve high compactness, it is preferable to use a solution in which one lateral support of the mold is fixed and the other lateral support is movable. However, in this case, since it is essential to obtain a shape that fits between the lateral support of the mold and the base in order to ensure optimal blow molding, controlling the movement to lift the base or bottom becomes a problem.

[0010] EP 2144742 B1 under the name KHS CORPOPLAST describes an apparatus for blow molding containers, in which the blow molding station is positioned on a support structure for molding preforms.

[0011] In this case, the blow molding station comprises two side walls of the mold and a base or bottom.

[0012] One side wall can be fixed, while the other can be oriented relative to the support structure. The bottom can be moved relative to each of the two side walls of the mold.

[0013] Specifically, the side walls of the mold are mechanically coupled to each other to perform positioning operations, and the bottom has a trajectory that has both a component extending longitudinally and a component extending transversely to the longitudinal direction relative to the side walls.

[0014] The solution proposed above has a certain structural complexity due to the movement trajectory of the bottom.

[0015] EP 3380300 B1 in the name of the present applicant describes an apparatus for blow molding a container, having a support frame for at least one station for blow molding a preform to obtain a container, the apparatus comprising two side bodies and a bottom adapted to provide at least one container by blow molding, at least one of the two side bodies being movable relative to the support frame about an articulated axis by means for periodic opening and closing in response to a command.

[0016] The device comprises means for a kinematic connection between the movable lateral body and the base, which is adapted to periodically cause movement of the base along a direction of movement substantially parallel to the axis of joint motion.

[0017] The means for periodic opening and closing includes an actuator supported by a connecting link mechanism, the connecting link mechanism being able to move relative to a support frame around a hinge axis substantially parallel to the joint axis of motion; the connecting link mechanism is kinematically connected to a movable lateral body and rotatably associated with a ripple body, the ripple body being able to move along a straight trajectory and forming a cam-like profile that can be engaged by an engaging element supported by the bottom.

[0018] While this solution is valid from a conceptual standpoint, it has several limitations. In particular, to ensure the possibility of moving the raised section along a straight trajectory, an operating connecting rod and an interconnecting rod, which are hinged to the raised section, are provided.

[0019] Firstly, it should be noted that the presence of interconnecting rods introduces certain difficulties in assembly and necessitates higher assembly precision in an attempt to reduce play.

[0020] Furthermore, the practical implementation of this solution requires the use of bearings at the ends of the interconnecting rods.

[0021] Another drawback of this solution relates to the fact that by rotatably coupling the ends of the interconnecting rod to the actuating connecting rod and the undulating body respectively, a constraint is formed against the movement of the interconnecting rod along the axis that is vertical during use, complicating the grooving of the actuating connecting rod and, if necessary, acting on the mold parts.

Prior Art Documents

Patent Documents

[0022]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Summary of the Invention

Problems to be Solved by the Invention

[0023] An object of the present invention is to provide a blow molding apparatus for plastic containers that solves the above problems, eliminates the above drawbacks, and is extremely easy to use and practical.

[0024] Within the scope of this object, an object of the present invention is to provide an apparatus for blow molding plastic containers that is extremely simple from a constructional point of view and enables optimal management of the process.

[0025] Another object of the present invention is to provide a blow molding apparatus that is flexible in its use.

Means for Solving the Problems

[0026] This objective, as well as these and other objectives which will become clearer below, is achieved by the apparatus for blow molding plastic containers according to claim 1.

[0027] Further features and advantages of the present invention will become more apparent from the description of some preferred but non-exclusive embodiments of the apparatus for blow molding plastic containers according to the present invention, as shown by non-limiting examples in the accompanying drawings. [Brief explanation of the drawing]

[0028] [Figure 1] This is a perspective view of the apparatus for blow molding a plastic container according to the present invention, in the open state. [Figure 2] This diagram is similar to Figure 1, showing the blow molding apparatus in the closed position. [Figure 3] This is a perspective view of the blow molding apparatus in its open state, from a different viewpoint. [Figure 4] This diagram is similar to Figure 3, showing the blow molding apparatus in the closed position. [Figure 5] This is a perspective view of a blow molding apparatus in a closed state. [Figure 6] This is a bottom view of the apparatus for blow molding plastic containers according to the present invention, in the open state. [Figure 7] This diagram is similar to Figure 6, showing the blow molding apparatus in the closed position. [Modes for carrying out the invention]

[0029] In the following embodiments, individual characteristics given in relation to a particular example may actually be interchangeable with other different characteristics present in other embodiments.

[0030] Referring to the drawings, the present invention relates to an apparatus for blow molding containers, generally indicated by reference no. 1, comprising a support frame 2 for at least one station 3 for blow molding a preform to obtain a container.

[0031] The blow molding station 3 includes two side bodies 3a, 3b and a bottom 3c, which are adapted to provide at least one container by blow molding.

[0032] At least one of the two lateral bodies 3a, 3b is movable by means of a mechanism for periodically opening and closing relative to the support frame 2 around an articulation axis 101 substantially parallel to the axis of the at least one container, in response to a command.

[0033] Preferably, both lateral bodies 3a and 3b can move around the joint axis in response to a command.

[0034] The blow molding apparatus 1 includes means 60 for a kinematic connection between at least one movable lateral body 3 and a base 3c, which is adapted to periodically cause movement of the base 3c along a direction of movement 200 that is substantially parallel to the joint axis of motion 101.

[0035] The periodic opening and closing mechanism includes an actuator 20 supported by a connecting link mechanism 11 that can move with respect to the support frame 2 about a pivot axis 100 which is substantially parallel to the joint motion axis 101.

[0036] Advantageously, the joint motion axis 101 is parallel to and spaced apart from the rotation axis 100.

[0037] However, the pivot axis 100 may coincide with the joint motion axis 101. The connecting link mechanism 11 is kinematically connected to the movable side column 3a or both side columns 3a, 3b, and is connected to the undulating body 12 by the connecting assembly 50.

[0038] The undulating body 12 can move along a substantially straight-line movement trajectory 103 relative to the support frame 2.

[0039] Conveniently, the support frame 2 supports the sliding guide 12b, which extends longitudinally parallel to the direction of movement 103, and a longitudinal profile 12a, which is integral with the undulating body 12, is slidably coupled to it.

[0040] The undulating body 12 forms a cam-shaped profile 13 that can be engaged by at least one engaging element 14 supported by the bottom 3c.

[0041] According to the present invention, the connecting assembly 50 includes an actuation attachment 51 that rotates integrally with the connecting link mechanism 11 around the pivot axis 100.

[0042] The operating attachment 51 supports a contact body 52 that slides into a sliding seat portion 53, which is integrated with the undulating body 12.

[0043] The sliding seat portion 53 is incident on the moving track 103 and extends along a sliding direction 104 that is substantially perpendicular to the pivot axis 100.

[0044] According to a preferred embodiment, the sliding direction 104 is substantially perpendicular to the moving track 103.

[0045] Preferably, the contact body 52 includes a roller 52a having a roller axis 105 substantially parallel to the pivot axis 100.

[0046] In particular, the roller 52a can be freely attached to the operating attachment 51. Conveniently, the sliding seat portion 53 is formed between two parallel and spaced-apart contact shoulder portions 53a and 53b.

[0047] According to one preferred embodiment, the distance between the two contact shoulders 53a, 53b substantially corresponds to the diameter of the roller 52a.

[0048] The sliding seat portion 53 is substantially U-shaped and forms an open end portion 53a that is oriented in the opposite direction to the undulating body 12.

[0049] Conveniently, the operating lever system includes a connecting link mechanism 11, which connects to the movable side block 3a.

[0050] Referring to the embodiment shown in the figure, the kinematic connection means 60 includes an actuation lever system 61 that connects the connecting link mechanism 11 to at least one movable side block 3a.

[0051] The operating lever system 61 acts particularly between the connecting link mechanism 11 and the movable side block 3a.

[0052] Furthermore, an additional lever allows the movable side block 3a to be connected to the other side block 3b, thereby enabling opening and closing movements for both side blocks 3a and 3b.

[0053] Conveniently, the kinematic connection means is configured to determine the rotation of the other lateral parallelepiped 3b by a second angular range around the joint axis 101 as a result of the rotation of the movable lateral parallelepiped 3a by a first angular range around the joint axis 101.

[0054] Preferably, the second angular range is greater than the first angular range. Advantageously, the engaging element 14 includes a free roller.

[0055] Apparatus 1 includes footings (both not shown) associated with a rotary rack, the rotary rack being able to rotate with respect to the footings about a rotary rack axis which is substantially parallel to the articulated axis 101, and supporting a plurality of blow molding stations 3.

[0056] The footing supports at least one engagement track for the actuator 20 so as the blow molding station 3 rotates around the rotary rack axis, the respective connecting link mechanisms 11 rotate around their respective pivot axes 100.

[0057] The operation of the apparatus according to the present invention is clear from the above description. In practice, the movement of the connecting link mechanism 11 with respect to the support frame 2 around the pivot axis 100 periodically generates movement of the bottom portion 3c along the direction of movement 102 and opening and closing of the movable lateral body 3a due to rotation around the joint motion axis 101.

[0058] The rotation caused by the oscillating motion of the connecting link mechanism 11 around each pivot axis 100 results in the opening and closing of the side bodies 3a and 3b through the intervention of the operating lever system 61, as well as the raising and lowering of the bottom 3c through the action of the undulating body 12.

[0059] The present invention, as conceived in this manner, is subject to numerous modifications and variations, all of which remain within the scope of the concept of the present invention.

[0060] The specific configuration of the connecting assembly 50 ensures the effective transmission of motion from the connecting link mechanism 11 to the undulating body 12.

[0061] Specifically, by disengaging the contact body 52 from the undulating body 12, it becomes possible to control any play and misalignment between the various components of the connecting assembly 50.

[0062] Furthermore, the specific shape of the sliding seat portion 53 allows the connecting link mechanism 11 to be easily disengaged from the undulating body 12, facilitating maintenance and formatting changes.

[0063] In practice, the materials used can be any, in accordance with the requirements, as long as they are suitable for the specific application, as well as their dimensions and shape.

[0064] All details may be further replaced with other technically equivalent elements. [Explanation of Symbols]

[0065] 1 Apparatus for blow molding a container, 2 Support frame, 3 Blow molding station, 3a, 3b Side parallelepipes, 3c Bottom, 11 Connecting link mechanism, 12 Relief body, 13 Cam-shaped profile, 14 Engaging element, 20 Actuator, 50 Connecting assembly, 51 Actuator attachment, 52 Contact body, 53 Sliding seat, 60 Means, 100 Swivel axis, 101 Joint motion axis, 102 Direction of movement, 103 Movement trajectory, 104 Sliding direction.

Claims

1. An apparatus (1) for blow molding a container, comprising a support frame (2) for at least one station (3) for blow molding a preform to obtain a container, wherein the blow molding station (3) includes two side bodies (3a, 3b) and a bottom (3c) adapted to provide at least one container by blow molding, and at least one of the two side bodies (3a, 3b) is, in response to a command, positioned relative to the support frame (2) and axially to the at least one container The support is movable by means for periodically opening and closing around a substantially parallel joint axis of motion (101), and means (60) are provided for a kinematic connection between the at least one movable side body (3a) and the bottom (3c), the means (60) being adapted to periodically determine the movement of the bottom (3c) along a direction of movement (102) substantially parallel to the joint axis of motion (101), and the means for periodic opening and closing is provided around a pivot axis (100) substantially parallel to the joint axis of motion (101) The system includes an actuator (20) supported by a connecting link mechanism (11) that can move relative to a frame (2), the connecting link mechanism (11) being kinematically connected to at least one movable lateral body (3a) and connected by a connecting assembly (50) to a ripple (12) that can move relative to the support frame (2) along a substantially linear movement trajectory (103), the ripple (12) being engaged by at least one engaging element (14) supported by the bottom (3c). Apparatus (1), characterized in that a cam-shaped profile (13) is defined, the connecting assembly (50) includes an actuating attachment (51) which is integral with the connecting link mechanism (11) during rotation around the pivot axis (100), the actuating attachment (51) supports a contact body (52) which slides into a sliding seat portion (53) which is integral with the undulating body (12), and the sliding seat portion (53) extends along a sliding direction (104) which is incident to the movement trajectory (103) and substantially perpendicular to the pivot axis (100).

2. The apparatus (1) according to claim 1, characterized in that the sliding direction (104) is substantially perpendicular to the moving track (103).

3. The apparatus (1) according to claim 1 or 2, wherein the contact body (52) includes a roller (52a) having a roller axis (105) substantially parallel to the pivot axis (100), and the roller (52a) is freely mounted on the operating attachment (51).

4. The apparatus (1) according to claim 3, characterized in that the sliding seat portion (53) is formed between two parallel and spaced-apart contact shoulder portions (53a, 53b).

5. The apparatus (1) according to claim 4, characterized in that the distance between the two contact shoulders (53a, 53b) substantially corresponds to the diameter of the roller (52a).

6. The apparatus (1) according to claim 1, characterized in that the sliding seat portion (53) is substantially U-shaped and forms an open end portion (53a) facing away from the undulating body (12).

7. The apparatus (1) according to claim 1, characterized in that the kinematic connecting means (60) includes at least one operating lever system (61) that connects the connecting link mechanism (11) to the at least one movable side block (3a).

8. The apparatus according to claim 1, characterized in that the at least one engaging element (14) includes a free roller.

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