MANUFACTURING OF CARDBOARD CONTAINERS WITH CLAMPS FORMED BY SECTIONS OF THE SIDE WALLS OF SUCH CONTAINERS FOR THE INSERTION OF VERTICAL PROPS

Abstract

A forming machine (100) for cardboard containers (10) with clamps (11) formed from sectors (5, 6) of the side walls (1, 2) of such containers (10) in a flat-folded state, comprising a folded container loader (20), a deployment mechanism (30), and an operational space (39) delimited above by an upper tamper (91) movable by a tamper actuator (86) positioned in a higher position, delimited below by one or more lower surfaces (41, 42, 52) for pressing lower flaps (3, 4) of the bottom of the container (10) with the upper tamper (91) in a lower position, and delimited around its perimeter by a clamp forming mechanism (60), comprising four folding devices (61), each with a folding member (62), for folding the sectors (5, 6) into the container (10) forming clamps (11) with internal holes (12) for inserting vertical struts (15).

Description

MANUFACTURING OF CARDBOARD CONTAINERS WITH CLAMPS FORMED BY SECTIONS OF THE SIDE WALLS OF SUCH CONTAINERS FOR THE INSERTION OF VERTICAL PROPS TECHNICAL SECTOR The technical field of the present invention is the devices for forming boxes from semi-rigid sheet material, for example, cardboard. OBJECT OF THE INVENTION The object of the present invention is a machine for forming cardboard containers with clamps formed by sectors of the side walls of such containers, starting from such containers in a flat folded state, for the insertion of vertical struts. Cardboard will be understood as any type of semi-rigid, fibrous-based material with a tendency to maintain its shape under external stress, for example, cardboard of the type of cardboard, compact cardboard, laminated cardboard, tensioned cardboard, as well as corrugated cardboard, mixed cardboard (combination of layers of paper and plastic), cardboard with an internal and / or external plastic sheet attached, among other options. BACKGROUND OF THE INVENTION AND TECHNICAL PROBLEM TO BE SOLVED The manufacture of cardboard containers with clamps formed from portions / sectors of the container's own side walls for receiving vertical struts, starting from the initially folded state of the container, is done entirely manually. Containers with such clamps are disclosed in documents US3054505A, ES2169629A1 and ES1057509U. The documents US4170929A, ES1010585U, ES2660059A1 (see web link https: / / www.youtube.com / watch?v=OpKXogRnFoM&t=6s), FR3085881B1 (see web link https: / / www.youtube.com / watch?v=KHbLPn2FpXw) and EP3795345A1 disclose respective machines for forming cardboard containers, for forming a cardboard container from a flat folded state to a folded container state with four paired side walls, and four lower extension flaps of the side walls that form a bottom of the container by joining said lower flaps together. However, none of the documents and web links cited above address the problem of the automation, by machine, of such cardboard containers with clamps formed by folding integral portions of the side walls of the container itself, ready for the subsequent insertion of the vertical struts. The technical problem to be solved is the reduction of manufacturing costs of cardboard containers initially flattened with clamps formed from portions / sectors of the container's own side walls for the reception of vertical struts. EXPLANATION OF THE INVENTION To overcome the problems mentioned in the previous section, the present invention presents a cardboard container forming machine, configured to form four clamps, one located in each of the four corner areas of the container, configured to position a vertical strut passing through an interior gap of the clamp in each corner area. Throughout this document, the term "vertical strut" means column or post, that is, an elongated element in the vertical direction, additional to the container, which has an extension preferably corresponding to the distance between the upper opening of the container and the bottom of the container to reinforce the container against stresses, for example, compressive stresses. The container forming machine comprises a folded container loader that includes two side structures between which flat-folded containers can be inserted, with a plurality of side panels parallel to another plurality of side panels forming the side walls of the container. Similarly, the container forming machine comprises a deployment mechanism with a forming device, and a deployment actuator attached to at least one suction cup configured to move the individually folded containers against the forming device to deploy the container. Throughout this document, the term "actuator" refers to a device consisting of two parts with relative movement controllable by control signals, for example, with a control device, such as a control device based on relays and contactors, a control device that includes an automaton or programmable logic controller (PLC), or a combination of these options. The drive may include a pneumatic cylinder with two parts: body and rod with relative movement, and / or a rotary electric motor with two parts: motor stator and rotor fixed to an output shaft with relative movement, and / or a rotary pneumatic actuator with two parts: support and rotating shaft, among other multiple options. Likewise, the container forming machine comprises an operational space, sized to accommodate an unfolded container with two first vertical side walls opposite each other and two second vertical side walls opposite each other, joined one after the other by vertical folds and forming four corner zones of the container. Also, the container forming machine comprises one or more lower surfaces positioned below adjacent to the operational space. Similarly, the container forming machine comprises an upper tamper that is vertically movable by a tamper actuator, between an upper position and a lower position. In the upper position, the upper tamper is positioned superiorly adjacent to the operational space. In the lower position, the upper tamper is configured to press, against one or more lower surfaces, lower bottom flaps of the container arranged horizontally and connected by horizontal folds to the side walls. The container forming machine also includes a clamp forming mechanism comprising four folding devices positioned around the perimeter of the operational space. Each folding device comprises a folding member, positioned in a corner area of ​​the operational space below the upper tamper in the upper position and above one or more lower surfaces. Likewise, in the container forming machine, the four folding members are movable by folding actuators between respective retracted and folding positions. In retracted positions, the folding members are adjacent to or outside the operational space. In the folded positions, the folding members are at least partially inserted into the operational space, configured to fold, inwards, in each corner area, two sections of two adjacent side walls, connected by a portion of one of the vertical folds and delimited by two parallel horizontal cuts, to form the aforementioned four clamps. Each clamp includes the two folded sections around three vertical fold portions to position a vertical strut passing through an interior opening of the clamp in the corner area of ​​the container. The present invention provides an automated solution for the manufacture of containers with inwardly folded clamps in the corner areas, which originate from a pair of parallel horizontal cuts made in each of the four corner areas, which have been largely assembled manually until now. Thus, the container with its clamps is manufactured automatically, on a machine, from the feeding into the loader of the flat-folded containers. The present invention provides a solution that greatly saves production time and container forming costs with clamps. This container forming machine with clamps offers a very significant reduction in production costs: it is a compact and highly productive unit since the clamp forming mechanism is strategically positioned on the machine, with the folding devices around the operational space, making it possible to take advantage of the container's downtime in the operational space due to the vertical movement of the upper press relative to one or more lower surfaces, further reducing production times. Optionally, the strategic arrangement of the folding devices surrounding the operational space enables the inward folding of the clamp sectors with precision and reliability, with the upper tamper inserted into the inner volume of the container, positionally limiting the side walls of the container, for example immediately before, after and / or during the pressing of the lower bottom flaps by the upper tamper and / or by the lower surfaces. The struts may be inserted into the interior volume of the container manually, by machine, by a combination of these options, or in any other way, leaving the four vertical struts positioned in stable positions between the inner faces of the side walls and the gaps of the four clamps. Other optional features and their associated advantages will be described later, in relation to the figures, in the preferred embodiments section. BRIEF DESCRIPTION OF THE DRAWINGS The above and other advantages and features will be more fully understood from the following detailed relationships of embodiment examples with reference to the accompanying drawings, which are to be taken as illustrative and not limiting, in which: Fig. 1 is a top perspective view of a container deployed by the deployment mechanism of the container forming machine of the present invention; Fig. 2 is a top perspective view of a container obtained with the container forming machine of the present invention, and in which the struts that can be inserted manually or by machine are also shown; Fig. 3 is a top perspective view of the clamp forming mechanism, of any one of the container forming machine embodiments of the present invention, and in which a container has been placed in the operational space; Fig. 4 is a rear top perspective view of one of the four folding devices of the clamp forming mechanism of Fig. 3; Fig. 5 is a front top perspective view of Fig. 4; Fig. 6 is a plan view associated with Fig. 3, with the folding members now in a retracted position, and where some elements have been omitted for clarity; Fig. 7 is the plan view of Fig. 3, with the folding members in the folded position; Figures 8 and 9 are plan views of a first and second embodiment, respectively, of the container forming machine of the present invention; Fig. 10 is a top perspective view of a part of the container forming machine of Fig. 9; Figs. 11 and 12 are plan views of an embodiment of the clamp forming mechanism alternative to that shown in Figs. 3 to 10; Fig. 13 is a plan view of a third embodiment of the container forming machine of the present invention; Fig. 14 is a top perspective view of Fig. 13; Figure 15 shows a part of the machine from Figures 13 and 14; Fig. 16 is an analogous view to Fig. 15, now with the container located within the operational space; Fig. 17 is a top perspective view of the head, a head that integrates the upper ram, the clamp forming mechanism, and the clamp actuators, included in Fig. 15; Fig. 18 is a bottom perspective view of Fig. 17; Figs. 19 and 20 show, respectively, a side view and a bottom perspective view of the clamp forming mechanism of Figs. 13 to 18; Fig. 21 shows a front top perspective view of the container forming machine of Fig. 13, where some elements have been omitted for clarity; Fig. 22 is a front top perspective view of the folding and pressing device included in Figs. 21 and 15; Fig. 23 shows a rear top perspective view of Fig. 21; and Fig. 24 is a rear top perspective view of Fig. 23. DETAILED EXPOSURE OF PREFERRED ACHIEVEMENTS In the figures, reference 100 generically designates the cardboard container forming machine (100) of the present invention, configured to form containers (10) with four clamps (11), located one in each of the four corner areas of the container (10), to position four vertical struts (15) passing through respective inner holes (12) of the four clamps (11). The vertical strut (15) in the figures is a slender and elongated element along the vertical direction, which has an extension preferably corresponding to the vertical distance between the upper opening and the bottom of the container (10) to reinforce it against stresses, for example, compressive stresses and / or lateral stresses during handling and transport of the same. The vertical struts (15) can be of different shapes (circular, square or triangular cross-section) and materials (fiber base: for example, paper, cardboard, etc.; or plastic, among other options). Common to all embodiments, Figs. 8, 9, 13 and 14 show that the container forming machine (100) (10) comprises a folded container loader (20) that includes two side structures (23), for example, plates or bars, between which flat-folded containers (10) can be inserted, with a plurality of side panels parallel to another plurality of side panels forming the side walls (1, 2) of the container (10), for positioning. Preferably, Figs. 8, 9, 13 and 14 show that the folded container loader (20) further comprises a support surface (22) arranged between the two side structures (23) where the flat-folded containers (10) can rest. Continuing with all embodiments, Figs. 8, 9, 13 and 23 show that the container forming machine (100) comprises a deployment mechanism (30). The deployment mechanism (30) comprises a forming device (31) and a deployment actuator (32) attached to at least one suction cup (33). The deployment actuator (32) is configured to suction-drive the individually folded containers (10) against the forming device (31) to deploy the container (10). The forming device (31) may be a plate, bars or rollers, among others. In Figures 8, 9, 13 and 23, the deployment actuator (32) is a rotating electric motor that drives a belt or chain (36) mounted on two rotating elements. A carriage (35) is fixed to the belt or chain (36), and at least one suction cup (33) is mounted on it. Figs. 3, 6, 8 to 11 and 15 show that the container forming machine (100) for containers (10) comprises an operational space (39), sized to accommodate a container (10) unfolded with two first vertical side walls (1) facing each other and two second vertical side walls (2) facing each other, joined one after the other by vertical folds and forming four corner zones of the container (10). Also, Figs. 8 to 10, 15, 16 and 21 to 24 show that the container forming machine (100) comprises one or more lower surfaces (41, 42, 52) positioned below adjacent to the operational space (39). In the first embodiment of Fig. 8, the container forming machine (100) has two lower surfaces (42, 42) positioned below adjacent to the operational space (39). In the second embodiment of Figs. 9 and 10, the container forming machine (100) has a lower surface (52) positioned below adjacent to the operational space (39). In the third embodiment of Figs. 13 to 24, the container forming machine (100) has four mutually facing lower surfaces (41, 41, 42, 42) in pairs. Each of these achievements will be described in detail later. Continuing in all embodiments, Figs. 8 to 10, 15, 17 and 18 show that the container forming machine (100) comprises an upper ram (91) movable vertically by a ram actuator (86), between an upper position and a lower position. The upper tamper (91) in Figs. 8 to 10 consists of a plate, while the upper tamper (91) in Figs. 15 to 18 consists of four lower pressure surfaces integrated into four corner assemblies of a head (90) to accommodate the spacing between these corner assemblies for different cardboard qualities and / or container sizes (10), reducing production downtime and therefore production costs. The upper tamper (91) can have a varied geometry. The ram actuator (86) in the figures is a rotary electric motor or a servomotor, although alternatively it may be a vertical pneumatic cylinder (not shown in the figures), among other options. In Figs. 13 to 24, the clamp actuator (86) is a rotary electric motor coupled to a reducer, which moves a horizontal shaft gear (not shown) coupled to a respective vertical linear rack (87) fixed to the main support (75), so that the rotation of the reducer's output shaft causes the vertical displacement of the clamp forming mechanism (60). Alternatively, the clamp actuator (86) is a rotary electric motor coupled to a reducer, which moves a horizontal shaft toothed wheel coupled to a respective vertically arranged endless belt or chain (not shown) that is fixed to the main support (75), so that the rotation of the reducer's output shaft causes the vertical displacement of the clamp forming mechanism (60). In the upper position, as may be represented by Figs. 8 and 9, shown in Fig. 10, the upper tamper (91) is positioned superiorly adjacent to the operational space (39). In the lower position, as may be represented by Figs. 8 and 9, and shown in Fig. 15, the upper tamper (91) is configured to press, against one or more lower surfaces (41, 42, 52), lower flaps (3, 4) of the bottom of the container (10) arranged horizontally and connected by horizontal folds to the side walls (1, 2) shown in Figs. 1 and 6 to 9. Common to all embodiments, Figs. 3 to 12, 14 to 21 and 23 show that the container forming machine (100) (10) further comprises a clamp forming mechanism (60) comprising four folding devices (61) positioned around the perimeter of the operational space (39). Continuing with these figures, each folding device (61) comprises a folding member (62), positioned in a corner area of ​​the operational space (39) below the upper tamper (91) in the upper position and above one or more lower surfaces (41, 42, 52). Figures 3 to 12 and 15 to 20 show that the four folding members (62) are movable by folding actuators (65) between respective retracted and folded positions. In the retracted positions of Figs. 6, 8, 9 and 11, the folding members (62) are adjacent to or outside the operational space (39). In the folding positions of Figs. 3, 10, 12, 15 to 21 and 23, the folding members (62) are at least partially introduced into the operational space (39) configured to fold, towards the inside of the container (10), in each of the corner zones, two sectors (5, 6) of two adjacent side walls (1, 2), shown in detail in Figs. 1 to 3. Each of these sectors (5, 6) are articulated by a portion of one of the vertical folds (8) and delimited by two parallel horizontal cuts (7). Thus, after obtaining the container (10) of Fig. 3 with the container forming machine (100) of the present invention, the vertical struts (15) can be positioned between the inner faces side walls (1, 2) and the four clamps (11) as shown in Fig. 2, either manually, by machine, a combination of these, or in any other way. Thus, with the movement of the folding members (62) between the retracted and folded positions, the aforementioned four clamps (11) are formed, each of which includes the two sectors (5, 6) folded around three vertical folding portions (9, 8, 9) to enable the positioning of a vertical strut (15) passing through an inner gap (12) of the clamp (11) in the corner area of ​​the container (10), as detailed in Fig. 2. With this, the container forming machine (200) obtains the container (10) shown in Fig. 3, where the clamps (11) are formed from portions or sectors (5, 6) of the side walls (1, 2) of the container (10) itself, folded inwards in stable positions, where preferably one sector (5) is perpendicular to the other sector (6), for the subsequent reception of the vertical struts (15). Preferably, in Figs. 3 to 12 and 13 to 20, each folding device (61) comprises one of said folding actuators (65) operatively connected to the folding member (32). Thus, the clamp forming mechanism (60) comprises four folding actuators, individually actuated in each corner area of ​​the container (10), configured to perform independent folding strokes for each clamp (11), ensuring the correct folding of the four clamps (11), consequently reducing downtime and production costs of the containers (10) with clamps (11). Alternatively, in an option not shown in the figures, the clamp-forming mechanism (60) comprises two folding actuators (65), each folding actuator (65) being configured to move two folding members (62). This can be accomplished by means of a gear attached to a folding actuator (55) that meshes with two auxiliary racks, each auxiliary rack moving one folding member (62). Optionally, Figs. 3, 10 to 12, 15 to 21 and 23 show that the clamp-forming mechanism (60) further comprises at least two mutually facing side surfaces (66), the side surfaces (66) being opposite each other on two opposite sides of the cavity (39), one on each side. Each side surface (66) is oriented vertically, being at least part of a side wall (1, 2) of the container (10) likely to come into contact with it. The side surfaces (66) provide improved positioning of the container (10), centering it, to undertake the pressing operation of the lower flaps (3, 4) with the movement of the upper tamper (91) against one or more lower surfaces (41, 42, 52), while accurately positioning the container (10) to undertake the folding of the clamps (11) with the folding members (62). Optionally, following Figs. 3, 10 to 12, 15 to 21 and 23, the clamp forming mechanism (60) comprises four mutually facing side surfaces (66) in pairs, the side surfaces (66) being opposite each other on two opposite sides of the cavity (39), two on each side. Additionally, Figs. 3, 7, 10 to 12 and 20 show that the clamp forming mechanism (60) comprises four supports (67), each folding device (61) being mounted on a respective support (67). These four supports (67) enable the positioning of folding devices (61) relative to each other when there is a change in the shape, for example, and / or size of the containers (10), for example, containers (10) with four or eight side walls (1, 2), all in a reduced adjustment / regulation time, without waiting time for replacement parts, reducing production costs. Preferably, Figs. 3, 7, 10 to 12 and 20 show that the clamp forming mechanism (60) comprises four supports (67), each folding device (61) being mounted on a respective support (67). Each folding device (61) comprises one of said folding actuators (65) linked to the folding member (62), and a side surface (66), all supported on a respective support (67). Preferably, Figs. 3 to 7, 11, 12, 15 and 20 show that the four supports (67) are mounted on a main support (75). Additionally, each folding device (61) further comprises a lateral positioning device (70, 71) that includes a linear guide (70) and a locking and release element (71) of the support (67) to the main support (75) to position the support (67) in a desired position along the linear guide (70) towards or away from the operational space (39) according to the lateral direction (L). In the figures, the linear guide (70) is an elongated hole and the release fixing element (71) is a screw element with a changing position along the elongated hole. Alternatively, the linear guide (70) includes a plurality of holes (not shown) aligned along the lateral direction (L). Alternatively, the linear guide (70) may be a recess / protrusion (not shown) where a conjugate recess / protrusion is slidable along the recess / protrusion. Optionally, Figs. 3 and 20 show that each folding device (61) comprises a second lateral positioning device (71, 72) that includes a linear guide (73) and the fixing and release element (71) of the support (67) to the main support (75) to position the support (67) in a desired position along the second linear guide (73) parallel to one side of the operational space (39), according to the parallel direction (P) of Figs. 3 and 20. Additionally, Figs. 3 and 4 show that each folding device (61) further comprises a folding adjustment device (68, 69) which includes a second linear guide (68) and a second locking and release element (69) for changing the folding and / or retracted position of the folding member (62). In Figs. 3 and 4, with the release of the second locking and release element (69) and its change along the second linear guide, one of the two relative movement parts of the folding actuator (65) is changed along the second linear guide (68), thus changing the position of the folding member (62). The lateral positioning device (70, 71), and / or second lateral positioning device (71, 72) and / or the folding adjustment device (68, 69), each or in combination, provide precision in the positioning and adjustment of the folding members (62) and / or the lateral surfaces (66), avoiding production stops and reducing production costs, as it provides robustness against different qualities and thicknesses of cardboard to be folded, absorbs severe tolerances of the cardboard (curvatures and deformations thereof), and all this against variations in measurements and / or shapes of the containers (10). Optionally, Figs. 3 to 7 show that each folding device (61) further comprises a vertical joint (63) operatively attached to the folding member (62), the folding members (62) being movable between the retracted and folding positions by pivoting about the vertical joints (63). These four vertical joints (63) provide reliability and robustness in the folding of the clamps (11) by the folding members (62), avoiding production stops and reducing production costs, in the face of different qualities and thicknesses of cardboard to be folded, absorbing variations in tolerances of the cardboard (curvatures and deformations thereof), in the face of variations in measurements and / or shapes of the containers (10). In Figs. 3 to 7, each vertical joint (63) connects one of the folding actuators (65) to the folding member (65). In Figs. 3 to 5, each folding device (61) further comprises a bi-articulated lever (64), articulated by one axis to the folding actuator (65) and articulated by another axis to the folding member (62). In an alternative embodiment (not shown in the figures), in each folding device (61), one of the parts provided with relative movement of the folding actuator (65) is articulated to the support (67) and the other part (for example, the rod of a pneumatic cylinder) has a toothed rack fixed to it which engages with the teeth of a toothed wheel fixed to one of said vertical joints (63), the folding members (62) being movable between the retracted and folded positions by pivoting about the vertical joints (63) in response to the rotation of the toothed wheels by the forward / reverse movement of the racks. In the first embodiment of the container forming machine (100) of Fig. 8, the container (10) is deployed by the movement of at least one suction cup (33) driven by a deployment actuator (32), for example, a rotating electric motor, which interferes with the movement of the forming device (31). The movement of the suction cup (33) is from a position adjacent to the folded container loader (20), shown in Fig. 8 as a dashed line, to an adjacent position where the at least one suction cup (33), shown as a solid line in Fig. 8, is positioned on one side of an auxiliary operating space that has adjacent, mutually facing first folding surfaces (41, 41) below it. The movement of the suction cups (33) may be linear along the first direction (X), optionally horizontal, from the position of the suction cup (33) in dashed line to the position of the suction cup (33) in solid line of Fig. 8. Subsequently, in Fig. 8, the partially formed container (10) is moved from the auxiliary operational space with the first lower flaps (3) folded by an auxiliary transfer device that includes a transfer actuator (37a), for example, an electric motor, which moves a second set of suction cups (not shown but analogous to the suction cups (33)) in the second direction (Y). Thus, the container (10) can be positioned by the auxiliary transfer device in the operational space (39) shown in Fig. 8, which is delimited above by the upper tamper (91) in the upper position and delimited below by the lower counter-pressure surfaces (42, 42) for pressing the lower flaps (3, 4) of the container (10) together against the upper tamper (91) in the lower position. In Fig. 8, the one or more lower surfaces (41, 42, 52) referred to above is a plurality of lower surfaces (42, 42) movable by bottom actuators (43), between pressure positions, where they are positioned adjacent to the upper tamper (91) in the lower position configured to press the horizontally arranged lower flaps (3, 4), and rest positions, where a plurality of lower surfaces (42, 42) are moved away from the position of the upper tamper (91) in the lower position. In Fig. 8, while the container (10) is housed in the operational space (39) without displacement, the folding members (62) moved by the folding actuators (65) fold the sectors (5, 6) of Figs. 1 and 3 into the interior of container 10 as shown in Fig. 3. When the upper ram (91) is moved to the upper position, the containers (10) that are moved individually by the transfer actuator (37a) push the containers (10) with clamps (11) formed successively housed in the operational space (39), ejecting them from it. In Figs. 9 and 10, the container (10) is deployed by the deployment mechanism (30) from the folded container loader (20) into an auxiliary operational space that has adjacent, mutually facing first dedicated folding surfaces (46, 46). Each first dedicated folding surface (41) is movable by a bottom actuator (43), folding the first dedicated folding surfaces (46, 46) by folding the first lower flaps (3). Subsequently, in Figs. 9 and 10, the partially formed container (10) is moved by an auxiliary transfer device that includes a transfer actuator (37a) which moves a second set of suction cups (37) mounted on a second support carriage (38), preferably linearly along the second direction (Y), and optionally horizontally. Thus, the container (10) can be positioned in a second auxiliary operational space shown in Figs. 9 and 10, where two mutually facing second dedicated folding surfaces (42, 42), each movable by a bottom actuator (43), fold the second lower flaps (4). In Figs. 9 and 10, the second suction cups (37) moved by the transfer actuator (37a) position the container (10) with the lower flaps (3, 4) folded essentially horizontally over the surface of a conveyor belt (52). In the second embodiment of the container forming machine (100) of Figs. 9 and 10, it comprises a folding device formed by dedicated folding surfaces (46, 46, 47, 47) movable by bottom actuators (43), and wherein the one or more lower counter-pressure surfaces (41, 42, 52) of the upper ram (91) is a surface corresponding to the surface of a conveyor belt (52). The operational space (39) of Figs. 9 and 10 is delimited above by the upper tamper (91) in the upper position and delimited below by the counter-pressure conveyor belt (52) to press the lower flaps (3, 4) of the container (10) together against the upper tamper (91) in the lower position. After the clamps (11) of the container (10) are formed by the folding members (62) with the container (10) housed without displacement inside the operational space (39), the container (10) is moved by the conveyor belt (52) driven by a transport actuator (51), for example, a motor, according to a transport direction (T) for evacuation. The supports (67) may be fixed in fixed positions during the cyclic operation of the container forming machine (100) (10), as can be represented in Figs. 3 to 10. Alternatively, the supports (67) of Figs. 3 to 10 may be movable laterally in approach / away from the sides of the operational space (39) by auxiliary actuators (55) that move secondary supports (76), shown in Figs. 11 and 12, to perform each cycle of lower flap pressing (3, 4) and clamp folding (11). It is noticeable that the first realization of Fig. 8 occupies less space on the floor plan than the realization of Fig. 9, thus reducing production costs. As can be seen in Figs. 8, 9 and 13, the third realization of Fig. 13 described below occupies less space in the plant, reducing production costs, compared to the first (Fig. 8) and second realizations (Fig. 9) described above. In the three realizations, the container forming machine (100) (10) is configured to fold all parts of the containers (10) with clamps without vertical displacement of the container (10), reducing downtime and increasing production costs. In the third embodiment of the container forming machine (100) of Figs. 13 to 24, the one or more lower surfaces (41, 42, 52) are a plurality of lower surfaces (41, 41, 42, 42) comprised in a folding and pressing device (45) located below and adjacent to the operational space (39). The folding and pressing device (45) further comprises bottom actuators (43) operatively connected to the plurality of lower surfaces (41, 41, 42, 42) to fold the lower flaps (3, 4) to a horizontal position and press them against the upper press (91), as shown in Fig. 16. Figures 15 and 16 and 21 to 24 show that the folding and pressing device (45) comprises four lower surfaces (41, 41, 42, 42) for counter-pressure against the upper tamper (91), a first pair of lower surfaces (41, 41) being mutually facing and associated with two sides of the operational space (39) and another second pair of lower surfaces (42, 42) being mutually facing and associated with the other two sides of the operational space (39), to fold and press the lower flaps (3, 3, 4, 4) together forming the bottom of the container (10). Thus, for example, in Figs. 14 to 16 and 21 to 24, the first pair of lower surfaces (41, 41) folds the lower flaps (3) and subsequently the second pair of lower surfaces (42, 42) folds the lower flaps (4) and presses the lower flaps (3, 4) together against the upper tamper in the lower position. Continuing with these figures, each lower surface (41, 41, 42, 42) is movable by at least one bottom actuator (43), for example, a pneumatic cylinder. Optionally, on the sides where pressure is applied to join flaps together, each lower surface (42, 42) is movable by two bottom actuators (43). This improves the joining of the lower flaps (3, 4), for example, by gluing or interlocking, improving the positioning and formation of the clamps (11), facilitating the subsequent insertion of the struts (15) manually or automatically, thus obtaining a robust and reliable solution that mitigates production stoppages and reduces production costs. Optionally, Figs. 14 and 21 to 24 show that on the side of the operational space (39) facing the folded container loader (20), the folding and pressing device (45) further comprises a lifting actuator (44) that is attached to a lifting carriage (48), on which the two bottom actuators (43) are mounted, which are capable of moving the lower surface (42), optionally guided by fixed guides (49) and conjugate guide skids fixed to the lifting carriage (48). Additionally, Figs. 13, 14, 21 and 23 show that the deployment mechanism (30) is configured to position the deployed container (10) in a partially formed working position within the operational space (39) with at least one suction cup (33) positioned laterally adjacent to the operational space (39). Additionally, Figs. 13, 14, 21 and 23 show that the container forming machine (100) (10) further comprises tamper side surfaces (92) rigidly attached to the upper tamper (91). In these figures, the container forming machine (100) comprises a head (90) with four corner assemblies, the lateral surfaces of the tamper (92) being bolted to corner surfaces of the upper tamper (91). Optionally, the side surfaces of the tamper (92) and the upper tamper (91) may be movable horizontally along the lateral direction (L) by pneumatic cylinders (93) mounted on the head (90), shown in Fig. 18. Alternatively, the tamper side surfaces (92) and the upper tamper (91) of Figs. 15 to 18 may form part of a single piece, as shown in Figs. 8 to 10. Optionally, Figs. 13 to 24 show that the container forming machine (100) further comprises a secondary actuator (81) and a vertical guide (82). The secondary actuator (81) is configured to move the clamp forming mechanism (60) along the vertical guide (82), between a lower operating position, where the four folding devices (61) are positioned around the perimeter of the operating space (39), and an upper operating position, where the four folding devices (61) are above the operating space (39). The secondary actuator (81) in the figures is a rotary electric motor. The vertical guide (82) in the figures is a guide rail attached to a carriage element fixed at a structural point of the machine, for example, to the chassis of the machine. In Figs. 13 to 24, the secondary actuator (81) is a rotary electric motor coupled to a reducer, which moves a horizontal shaft toothed wheel coupled to a respective vertical rack (83) fixed to the main support (75), so that the rotation of the reducer's output shaft causes the vertical displacement of the clamp forming mechanism (60). Alternatively, the secondary actuator (81) is a rotary electric motor coupled to a reducer, which moves a horizontal shaft gear coupled to a respective vertically arranged endless belt or chain that is fixed to the main support (75), so that the rotation of the reducer's output shaft causes the vertical displacement of the clamp forming mechanism (60). In another option not shown, the secondary actuator (81) is a vertical fluid dynamic cylinder attached to the main support (75). Optionally, once the struts (15) are inserted into the clamps (11) of the container (10) resting on the bottom as shown in Fig. 2, either manually or by machine, the containers (10), for the formation of the upper reinforced mouth with upper reinforcement flaps (13, 14) initially vertically shown in Figs. 1 and 2 connected by horizontal slits to the upper part of the side walls (1, 2), can be formed by the upper forming device 240 for reinforced mouths of document ES1306046U of the same inventor as the present application: - either by installing the forming assemblies 245 on the main support (75) of the third embodiment of the forming machine (100) of Figs. 13 to 24 of the present invention, or - either by means of an additional machine to the present invention that incorporates the upper forming device 240 of said document ES1306046U. The scope of the present invention is defined by the following claims.

Claims

1. A cardboard container forming machine (100), comprising: a folded container loader (20) including two side structures (23) between which flat-folded containers (10) can be inserted, with a plurality of side panels parallel to another plurality of side panels, forming the side walls (1, 2) of the container (10); a deployment mechanism (30) with a forming device (31), and a deployment actuator (32) attached to at least one suction cup (33) configured to move the individually folded containers (10) against the forming device (31) to deploy the container (10); an operational space (39), dimensioned to accommodate an deployed container (10) with two first vertical side walls (1) opposite each other and two second vertical side walls (2) opposite each other,joined one after the other by vertical folds and forming four corner zones of the container (10); one or more lower surfaces (41, 42, 52) positioned below adjacent to the operational space (39); an upper tamper (91) movable vertically by a tamper actuator (86), between an upper position, in which the upper tamper (91) is positioned above adjacent to the operational space (39), and a lower position, in which the upper tamper (91) is configured to press, against the one or more lower surfaces (41, 42, 52), lower flaps (3, 4) at the bottom of the container (10) arranged horizontally and connected by horizontal folds to the side walls (1, 2); characterized in that it further comprises a clamp forming mechanism (60) comprising four folding devices (61) positioned around the perimeter of the operational space (39),each folding device (61) comprising a folding member (62), positioned in a corner zone of the operational space (39) below the upper foot (91) in the upper position and above one or more lower surfaces (41, 42, 52), and wherein the four folding members (62) are movable by folding actuators (65) between retracted positions, wherein the folding members (62) are adjacent to or outside the operational space (39), and folded positions, wherein the folding members (62) are at least partially inserted into the operational space (39), configured to fold in each of the corner zones, inwards into the container (10), two sections (5, 6) of two contiguous side walls (1, 2), articulated by a portion of one of the vertical folds (8) and bounded by two parallel horizontal cuts (7), to form four clamps (11),Each of which includes the two sectors (5, 6) folded around three vertical fold portions (9, 8, 9) to position a vertical strut (15) passing through an inner recess (12) of the clamp (11) in the corner area of ​​the container (10).

2. Forming machine (100) according to claim 1, wherein each folding device (61) comprises one of said folding actuators (65) operatively connected to the folding member (32).

3. Forming machine (100) according to claim 1 or 2, wherein the clamp forming mechanism (60) further comprises at least two mutually facing side surfaces (66) on two opposite sides of the cavity (39).

4. Forming machine (100) according to any one of the preceding claims, wherein the clamp forming mechanism (60) comprises four supports (67),5. Forming machine (100) according to the combination of claims 2, 3 and 4, wherein each folding device (61) comprises one of said folding actuators (65) and one of said side surfaces (66).

6. Forming machine (100) according to claim 4 or 5, wherein the four supports (67) are mounted on a main support (75), and wherein each folding device (61) further comprises a lateral positioning device (70, 71) including a linear guide (70) and a locking and release element (71) of the support (67) to the main support (75) to position the support (67) in a desired position along the linear guide (70) in approach to or away from the operational space (39).

7. Forming machine (100) according to claim 6, wherein each folding device (61) further comprises a folding adjustment device (68,69) which includes a second linear guide (68) and a second locking and release element (69) for changing the folding and / or retracted position of the folding member (62).

8. Forming machine (100) according to any one of the preceding claims, wherein each folding device (61) further comprises a vertical joint (63) operatively connected to the folding member (62), the folding members (62) being movable between the retracted and folded positions by pivoting about the vertical joints (63).

9. Forming machine (100) according to any one of claims 1 to 8, wherein the one or more lower surfaces (41, 42, 52) is a plurality of lower surfaces (42, 42) movable by bottom actuators (43), between pressing positions, wherein they are positioned adjacent to the upper press (91) in a lower position configured to press the horizontally arranged lower flaps (3, 4),and rest positions, wherein a plurality of lower surfaces (42, 42) are moved away from the position of the upper ram (91) in the lower position.

10. Forming machine (100) according to any one of claims 1 to 8, further comprising a folding device formed by dedicated folding surfaces (46, 46, 47, 47) movable by bottom actuators (43), and wherein one or more lower counter-pressure surfaces (41, 42, 52) of the upper ram (91) correspond to the surface of a conveyor belt (52).

11. Forming machine (100) according to any one of claims 1 to 8, wherein the one or more lower surfaces (41, 42, 52) is a plurality of lower surfaces (41, 41, 42, 42) comprising a folding and pressing device (45) located below adjacent to the operational space (39),further comprising bottom actuators (43) operatively connected to the plurality of lower surfaces (41, 41, 42, 42) for folding the lower flaps (3, 4) to a horizontal position and pressing them against the upper tamper (91).

12. Forming machine (100) according to claim 11, wherein the deployment mechanism (30) is configured to position the deployed container (10) in a partially formed working position within the operational space (39) with at least one suction cup (33) positioned laterally adjacent to the operational space (39).

13. Forming machine (100) according to any one of the preceding claims, further comprising lateral tamper surfaces (92) rigidly connected to the upper tamper (91).

14. Forming machine (100) according to claim 11, further comprising a secondary actuator (81) and a vertical guide (82),with the secondary actuator (81) configured to move the clamp forming mechanism (60) along the vertical guide (82), between a lower operating position, where the four folding devices (61) are positioned delimiting the perimeter of the operating space (39), and an upper operating position, where the four folding devices (61) are above the operating space (39).

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