EP4045430A1 - Pallet container - Google Patents

Abstract

The present invention relates to a pallet container (10) for storing and transporting liquid or free-flowing filling materials, having a thin-walled, rigid inner plastic container (12) made of thermoplastic, having a tubular lattice frame (14), which tightly encloses the inner plastic container (12) as a supporting jacket and which is made of welded-together horizontal and vertical tubular rods (18, 20), and having a base pallet (16) on which the inner plastic container (12) rests and to which the tubular lattice frame (14) is firmly connected, wherein at least two rod-shaped crossbeams (22) are provided above the inner plastic container (12), the two ends of which are fastened to two opposing lateral walls in the upper region of the tubular lattice frame (14). In order to protect the upper region of the tubular lattice frame (14) against adverse effects of impact stresses and transport vibrations, according to the invention, the crossbeams (22) are designed as resilient spring elements (24).

Description

Pallet container

The present invention relates to a pallet container for the storage and transport of liquid or flowable products with a thin-walled rigid inner container made of thermoplastic material, with a tubular lattice frame that tightly encloses the plastic inner container as a support jacket made of horizontal and vertical tubular rods welded together, and with a floor pallet on which the plastic inner container rests and with which the tubular lattice frame is firmly connected, with two rod-shaped cross members being provided above the plastic inner container, the two ends of which are located on two opposite side walls in the upper region of the tubular lattice frame are attached.

The rod-shaped crossbars are intended to prevent excessive bulging of the plastic inner container or its top floor with a central screw cap, especially in the event of transport vibrations and dynamic vibrations, and also serve, among other things, to keep the plastic inner container in the tubular lattice frame on the floor pallet in the event of the pallet container accidentally tipping over to hold and to prevent slipping out of the tubular lattice frame. In order to enable the plastic inner container to be easily exchanged for multiple use of the pallet container, the two ends of the cross members are releasably fastened in the upper area of the tubular lattice frame, usually screwed.

Such a pallet container with two parallel cross members is z. B. from the publication WO 2012085940 A2. In a pallet container described in DE 44 25 630 A1, four cross members are provided, two cross members crossing at an angle each covering one half of the plastic inner container.

Problem:

If pallet containers are used for the storage and transport of dangerous liquid filling goods such as B. aggressive chemicals are to be used, then these pallet containers require a so-called hazardous goods approval from a national official testing agency, in Germany this is the BAM (Federal Institute for Materials Testing). To a

CONFIRMATION COPY To obtain such dangerous goods approval, the different types of pallet containers are subject to a special type test with different load conditions such as z. B. subjected to an internal pressure test, drop test and vibration test. In the vibration test, heavy transport loads (shocks, shocks) are simulated on a filled pallet container. The liquid column in the plastic inner container can get into strong dynamic vibrations. These vibrations cause strong alternating loads on the side walls of the plastic inner container and are transmitted directly to the tubular lattice frame which tightly encloses the plastic inner container as a support jacket. Since a pallet container usually has two longer and two shorter side walls, the two longer opposing side walls are loaded to a greater extent and are therefore stabilized by the cross-members that extend over them. Likewise, the top of the plastic inner container carries out strong dynamic up and down vibrations, which act on the cross members. If the top floor bulges up, the well-known straight, parallel crossbars are pushed upwards and strong tensile stresses act on the two attachment points of the crossbars on the pipe lattice frame between the opposing side walls of the pipe lattice frame, whereby the upper area of the pipe Grid frame is pulled inwards. When the top floor is lowered, the opposite side walls of the plastic inner container and of the tubular lattice frame bulge outwards, with the upper area of the tubular lattice frame also being pressed outwards. In this case, the cross members with their two fastening points are again subjected to a high tensile load. This alternating load is repeated at high frequency over a long period of time and has a grueling effect on the corresponding components of a pallet container.

Task:

It is the object of the present invention to reduce these disadvantageous tensile stresses and to intercept the effect of tensile loads on the fastening points of the crossbars and accordingly on the upper area of the tubular lattice frame and to alleviate stress peaks. Solution:

The intended reduction of disadvantageous tensile stresses is achieved in that the two rod-shaped cross members are designed as elastic spring elements. Due to the elastic design of the two crossbars as spring elements, the rigid connection of the previously common linear, straight crossbars with the opposite side walls of the tubular lattice frame is dissolved and a limited elasticity is "built into" the upper level of the tubular lattice frame. If the top floor bulges upwards, the tensile forces that occur on the two fastening points of the crossbars are softened and the upper area of the tubular lattice frame is less drawn inwards. In the event of a lateral bulging of the plastic inner container and the associated bulging of the opposite side walls of the tubular lattice frame outwards, the tensile forces occurring in the upper area of the tubular lattice frame are considerably reduced by the cross members designed as elastic spring elements and the operational safety of filled pallet containers with dynamic Transport loads increased noticeably.

According to the present invention, it is provided that the cross members, which are designed as elastic spring elements, are not designed to run linearly, but rather each have one or more arcuate sections. The actual length of the crossbars between their two fastening points is greater than the direct distance between the two fastening points at the ends of the crossbars in the upper region of the tubular lattice frame. Due to this structural design, on the one hand the cross members are flexible in their horizontal longitudinal direction under tensile load - when the tubular lattice frame bulges outwards - and on the other hand they are also flexible in the case of lateral pressure load - due to an upward bulging of the top of the plastic inner container - in designed flexible in the vertical direction.

In an embodiment of the invention, this is realized in that the cross members between their two fastening points are not linear, but rather arcuate and have a comparatively large curve. The formation of the two cross members as elastic spring elements is achieved in a preferred design by means of an arched, curved shape with a large molded-in arch. The cross members - viewed in the installed state - are curved in the horizontal plane, the arches each having a comparatively large radius and directed outwards in the direction of the two opposite shorter side walls of the tubular lattice frame. In the installed state, the arched, curved cross members lie flat on the top of the plastic inner container, the arches of the two cross members being oriented away from one another.

The two cross members are expediently guided through a holding device in the form of a closed holding eyelet formed from the top of the plastic inner container. In a modified form, the holding devices formed from the top of the plastic inner container can also be designed as support pins that are open on one side. These support pins, which are open on one side, are also referred to below as hook eyes.

The closed eyelets or the support pins open on one side are arranged laterally next to the central filling opening of the plastic inner container, which can be closed by means of a screw cap, and the center of the arch of the two crossbars is located exactly under a retaining eyelet or under a support pin. The cross members with their curved shape can on the one hand with a bulging of the topsoil up and down - z. B. also with an internal pressure or drop test - yield elastically in the vertical direction and adapt to the bulge, they practically “follow” the shape of the topsoil.

In another embodiment of the invention, the cross members, as elastic spring elements, can also be equipped with two or three smaller arches with comparatively smaller radii.

The fastening points of the curved, arched crossbars are - compared to the straight crossbars that have been customary up to now - shifted further towards the middle of the upper area of the tubular lattice frame, where the largest bulges with the greatest tensile loads occur and are to be absorbed. During the vibration test, the curved cross member acts like an elastic spring. During the vibration, the top of the inner container swings up and down. In their upper and lower end points, these vibrations cause an elastic upward and downward bending of the straight crossbars that were customary up to now, which is converted directly into a shortening of the distance between the fastening points. As a result of this shortening of the distance, the tubular lattice frame in the upper area is pulled significantly inwards with each stroke. With the new “spring solution”, which is also flexible in the longitudinal direction, on the other hand, a significantly reduced deformation is achieved at the upper edge of the tubular lattice frame and thus a reduced load on the pallet container.

In order to obtain optimal elasticity and spring action of the crossbars, it is provided that the length of the crossbars is made between 1% and 5% greater than the direct distance (corresponding to a chord) between the two fastening points, according to their arc line between their two fastening points. As a result, the size of the arch and the arched, curved shape of the crossbars are implemented as an elastic spring element.

In a preferred embodiment of the invention it is provided that the two ends of the cross members are strongly squeezed in the radial direction, a corresponding internal thread, z. B. M8 is molded and the two ends of the crossbars are screwed tightly at the end to an upper horizontal or vertical tubular rod of the tubular lattice frame. For this design variant, the procedure is that the two ends of the cross members are each screwed on the front side at the upper end of two adjacent vertical tubular rods.

In another embodiment of the invention it is provided that a screw nut with an internal thread is firmly inserted into the two ends of the crossbars and the crossbars are firmly screwed onto an upper horizontal or vertical tubular bar of the tubular lattice frame at the front side - in the axial direction, so to speak. The screw nut, which is firmly and non-detachably inserted into the cross member, which is designed as a hollow tube profile, can simply be pressed in, squeezed or welded.

The invention is explained and described in more detail below with reference to the exemplary embodiments shown in the drawings. Show it: Figure 1 is a perspective view of a pallet container according to the invention,

FIG. 2 shows an enlarged partial view of the upper area of the pallet container according to the invention according to FIG. 1,

FIG. 3 shows a plan view of a cross member designed as a spring element,

Figure 4 is a side view of another embodiment of a cross member,

Figure 5 is an enlarged partial view of the left end area of the cross member according to Figure 4,

FIG. 6 shows an enlarged partial view with the connection of a cross member to the upper area of a tubular lattice frame,

FIG. 7 shows, in an enlarged partial view, the right end area of a cross member with an inserted screw nut,

FIG. 8 is an enlarged partial cross-sectional view with an end face

Screw connection of a cross member to the upper area of the tubular lattice frame,

FIG. 9 shows a partial view of a flaken eyelet (support pin) which is formed from the top of the plastic inner container and grips over a transverse traverse

FIG. 10 shows an enlarged partial cross-sectional view with a conventional connection of a cross member to the upper region of the tubular lattice frame

FIG. 1 shows a pallet container 10 according to the invention (also referred to as “IBC” = intermediate bulk container) for storing and transporting liquid or flowable filling goods. The pallet container 10 comprises a thin-walled, rigid plastic inner container 12 made of thermoplastic material, a tubular lattice frame 14 made of horizontal and vertical tubular rods 18, 20 welded to one another and which tightly encloses the plastic inner container 12 as a support jacket Floor pallet 16 on which the plastic inner container 12 rests and with which the tubular lattice frame 14 is firmly connected. Above the plastic inner container 12, two rod-shaped cross members 22 are provided, which are fastened with their two ends to two opposite side walls of the upper tubular lattice frame 14. The two cross members 22 are designed as elastic spring elements 24 in an arcuate shape. The particular structural configuration of the cross members 22 is characterized in that they are not straight or linear, but are arcuate between their two fastening points 26, 28 and have a comparatively large arc 34. The length of the crossbars 22 between their two fastening points 26, 28 is, in a completely unusual way, greater than the direct distance between the two fastening points 26, 28 at the ends of the crossbars 22. In the present embodiment, the fastening points 26, 28 are at the ends the crossbars 22 each arranged on two vertical bars just below the topmost horizontally circumferential tubular rod 18 between two opposing side walls of the tubular lattice frame 14.

In the specific case, the length of the cross members 22 between their two fastening points 26, 28 is between 1% and 5%, preferably 3%, greater than the direct distance between the two fastening points 26, 28.

For standard pallet containers with a filling volume of 600, 1000 or 1200 liters that have the same width and length dimensions, the distance between the two fastening points 26, 28 is approx. 960 mm and the effective length of the crossbars 22 is approx. 993 mm. For the same standard pallet container, the curved cross members 22 should have a large arc radius between 300 mm and 700 mm, preferably 500 mm.

The structural configuration of the invention described above can be seen in greater detail in FIG. 2 in an enlarged section. It becomes clear that the curved cross members 22 - when installed - lie flat in the horizontal plane on the top floor 38 of the plastic inner container 12, the large arches 34 of the two cross members 22 pointing away from each other. In a modified embodiment it can be provided that the cross members 22 are designed as elastic spring elements with two or three smaller arches aligned in the horizontal plane with comparatively smaller radii.

In any case, the curved cross members 22 - in the installed state - are each guided through a holding eyelet 40 formed from the top floor 38 of the plastic inner container 12, the holding eyelets 40 being arranged overlapping in the center of the built-in arcuate cross members 22 (a different shape the retaining eyelets is shown in Figure 9).

FIG. 3 shows a plan view of an arcuate cross-member 22 designed as a spring element with a large arc radius of approximately 500 mm. The cross members can be designed as a hollow tube with a round or square cross-section.

In a preferred embodiment, the cross members 22, 42 have a round tubular profile with a diameter between 16 mm and 24 mm, preferably 20 mm, and a wall thickness between 0.8 mm and 1.2 mm, preferably 0.9 mm.

According to another design, the cross members 22, 42 can also have a square tubular profile with a side length between 14 mm and 20 mm, preferably 16 mm, and a wall thickness between 0.8 mm and 1.2 mm, preferably 0.9 mm .

FIG. 4 shows a side view of another embodiment of a cross member with two arches 42, which in their end regions - viewed in the installed state - each have a downwardly shaped small arch 36 with a comparatively small radius and ends pointing upwards and (as in FIG FIG. 8 can be seen in detail) are each screwed on the front side from below against the uppermost circumferential horizontal tubular rod 18. One end of the cross member with 2 arcs 42 with small arcs 36 formed downwards with a small radius is shown in an enlarged partial view in FIG. A screw nut 30 with an internal thread 44 (for example M8 or M10) is firmly inserted in each of the open ends of the hollow tube profile of the cross member with 2 arches 42 (see also FIG. 7). The non-detachably inserted screw nut 30 can simply be pressed in, squeezed or welded in. A fastening option in which a threaded screw 48 is screwed into the end of the hollow tube profile of the cross member 22 can be seen in FIG. The cross member 22 is fixed just below the uppermost horizontal tubular rod 18 by means of the threaded screw 48 screwed in at the end from the outside - in the horizontal direction - on the upper flattened ends of two opposite vertical tubular rods 20.

Figure 7 shows in a corresponding manner the open end of the hollow tube profile of the cross member 22 (with only one large arch) with firmly inserted screw nut 30 with internal thread 44. The cross member with 2 arches 42 is as described above at the front from below against the uppermost circumferential horizontal tubular rod 18 of the tubular lattice frame firmly but releasably screwed on again.

Another fastening option with frontal screwing of the cross member with 2 arches 42 is shown in an enlarged illustration in FIG. Here, the two ends of the cross members are strongly squeezed in the radial direction with two arches 42, with a corresponding internal thread 46 being molded directly into the squeezes 32. The crossbars with 2 arches 42 with the smaller arches at their end areas are fixed at the front from below against the uppermost horizontal tubular rod 18 by means of a threaded screw 48 screwed in from above - in the vertical direction. The uppermost horizontal tubular rod 18 is expediently sunk somewhat at the top of the borehole and the threaded screw 48 is designed as a flat head, countersunk head or pan head screw so that it does not protrude upwards. The squeezes 32 with a correspondingly formed internal thread 46 can of course also be implemented in the transverse traverse 22 (with only one large arc). The screw connections on the face also have the advantage that the screw tip sits completely in the hollow tube profile of the crossbars 22, 42 and is covered, so that no more injuries can occur as a result, as is often the case with open screw connections with protruding screw tips was.

Straight traverses that have been customary up to now cannot be screwed directly into the central axis with screws on the front side. When the screws are tightened, the traverse rotates with them and must be fixed for assembly. This fixation is not necessary with the curved shape of the crossbars. As mentioned above, the curved cross members 22 - in the installed state - are each guided through a holding eyelet 40 formed from the top floor 38 of the plastic inner container 12. In another embodiment, the retaining eyelets 40 can also be designed as support pins 50 open on one side (also referred to as hook eyelets), as shown in FIG. In this case, the arcuate cross members 22 are overlapped and fixed centrally from the outside to the inside by the support pins 50, which are solidly formed by thickening of the material.

The differently designed versions of the crossbars 22, 42 allow a different design of the attachment of the two ends of the crossbars 22, 42 on the upper tubular lattice frame 14. In addition to the front attachments described, the ends 52 of the crossbars 22, 42 - in a manner known per se - Also flattened, placed around the topmost horizontal bar of the tubular lattice frame 14 and screwed by means of a threaded screw 54 below the topmost horizontal tubular bar 8, as can be seen in FIG.

In a combined form, the cross members 22, 42 can also be designed as elastic spring elements with two smaller arches aligned in the vertical plane with comparatively smaller radii and one, two or three smaller arches aligned in the horizontal plane with comparatively smaller radii. Such a formation can be of interest for a torque-neutral design. The described embodiments of the cross members and the fastening options can be easily combined with one another or exchanged for one another within the scope of the present invention - as far as technically possible.

Conclusion: Due to the inventive design of the cross members 22, 42 as elastic spring elements, the upper area of the tubular lattice frame 14 in a pallet container 10 can be protected against the adverse effects of transport vibrations and dynamic shock loads in a comparatively simple manner and the operational safety when handling filled pallet containers are increased. Reference number list

Pallet container

Plastic inner container

Tube lattice frame

Floor pallet horizontal tube bars (14) vertical tube bars (14)

Cross member spring element (22)

Fastening point (22) opposite fastening point (22) screw nut (22)

Pinching (22) large arch (22) small arch (22)

Topsoil (12)

Retaining eyelet (38)

Cross beam 2-arch internal thread (30)

Internal thread (32)

Threaded screw (30, 32)

Hook eye or lifting pin (38, 12)

End of cross member (22, 42) Threaded screw (22, 42)

Claims

Claims 1.) Pallet container (10) for the storage and transport of liquid or flowable filling goods with a thin-walled rigid plastic inner container (12) made of thermoplastic material, with a tubular lattice frame (14) that tightly encloses the plastic inner container (12) as a support jacket made of horizontal and vertical tubular rods (18, 20) welded to one another, and with a floor pallet (16) on which the plastic inner container (12) rests and to which the tubular lattice frame (14) is firmly connected, with above the plastic Inner container (12) two rod-shaped cross members (22) are provided, which are attached with their two ends to two opposite side walls in the upper region of the tubular lattice frame (14), characterized in that the two rod-shaped cross members (22, 42) as elastic spring elements (24) are formed. 2.) Pallet container (10) according to claim 1, characterized in that the two cross members (22, 42) designed as elastic spring elements (24) are not formed to run linearly, but each have one or more arcuate sections. 3.) Pallet container (10) according to claim 1 or 2, characterized in that the length of the cross members (22, 42) between their two fastening points (26, 28) is greater than the direct distance between the two fastening points (26, 28) the cross members (22, 42) at their ends in the upper region of the tubular lattice frame (14). 4.) Pallet container (10) according to claim 1, 2 or 3, characterized in that the cross members (22) between their two fastening points (26, 28) are non-linear but are arcuate and have a comparatively large arc (34). 5.) Pallet container (10) according to claim 1, 2, 3 or 4, characterized in that the cross members (22) - viewed in the installed state - are bent in the horizontal plane, the large arches (34) each outward in the direction of two opposite shorter side walls of the tubular lattice frame (14) are directed, the arched curved cross members (22) lying flat on the top (38) of the plastic inner container (12) and the large arches (34) of the two cross members (22 ) are aligned facing away from each other. 6.) Pallet container (10) according to claim 1, 2, 3, 4 or 5, characterized in that the length of the cross members (22) between their two attachment points (26, 28) between 1% and 5%, preferably 3% greater is designed as the direct distance between the two fastening points (26, 28). 7.) Pallet container (10) according to claim 1, 2, 3, 4, 5 or 6, characterized in that the distance between the two fastening points (26, 28) for standard pallet containers with a filling volume of 600, 1000 or 1200 liters approx 960 mm and the effective length of the crossbars (22) is approximately 993 mm. 8.) Pallet container (10) according to claim 1, 2, 3, 4, 5, 6 or 7, characterized in that the curved cross members (22) for standard pallet containers with a filling volume of 600, 1000 or 1200 liters a large Curve radius between 300 mm and 700 mm, preferably 500 mm, have. 9.) Pallet container (10) according to one of the preceding claims 1 to 8, characterized in that the two ends of the cross members (22, 42) are strongly squeezed and an internal thread (46) is formed directly in the squeezes (32) and the both ends the crossbars (22, 42) are firmly screwed on the end face to an upper horizontal or vertical tubular rod (18) of the tubular lattice frame (14). 10.) Pallet container (10) according to one of the preceding claims 1 to 9, characterized in that a screw nut (30) with an internal thread (44) is inserted at the end of the two ends of the cross members (22, 42) and at the end of an upper one horizontal or vertical tubular rod (18) of the tubular lattice frame (14) are firmly screwed. 11.) Pallet container (10) according to one of the preceding claims 1 to 10, characterized in that the two ends of the cross members (22, 42) are each screwed on the front side on the upper region of two adjacent vertical tubular rods (20). 12.) Pallet container (10) according to claim 1, 2, 3, 6 or 7, characterized in that the cross members with two arches (42) between their two attachment points (26, 28) are not linear and each have one at their two ends - viewed in the installed state - have downwardly formed small arches (36) with a comparatively small radius and are each screwed on the front side from below against the uppermost circumferential horizontal tubular rod (18). 13.) Pallet container (10) according to one of the preceding claims 1 to 12, characterized in that the cross members (22, 42) have a round tubular profile with a diameter between 16 mm and 24 mm, preferably 20 mm, and a wall thickness between 0.8 mm and 1.2 mm, preferably 0.9 mm. 14.) Pallet container (10) according to one of the preceding claims 1 to 13, characterized in that the cross members (22, 42) have a square tubular profile with a side length between 14 mm and 20 mm, preferably 16 mm, and a wall thickness between 0, 8 mm and 1.2 mm, preferably 0.9 mm. 15.) Pallet container (10) according to one of the preceding claims 1 to 3, 6, 7, 9-11 and 13, characterized in that the cross members (22) as elastic spring elements with two or three smaller arches aligned in the horizontal plane with comparatively smaller ones Radii are formed. 16.) Pallet container (10) according to one of the preceding claims 1 to 3, 6, 7, 9-11, 13 and 15, characterized in that the cross members (42) as elastic spring elements with two smaller arches aligned in the vertical plane with comparatively smaller ones Radii and two or three smaller arcs aligned in the horizontal plane are formed with comparatively smaller radii. 17.) Pallet container (10) according to one of the preceding claims 1 to 16, characterized in that the curved cross members (22, 42) - in the installed state - each by one from the top (38) of the plastic inner container (12) shaped retaining eyelets (40) are guided and the retaining eyelets (40) are arranged in the middle of the curved cross members (22, 42). 18.) Pallet container (10) according to one of the preceding claims 1 to 16, characterized in that the curved cross members (22, 42) - in the installed state - each below one of the top (38) of the plastic inner container (12) shaped hook eye (50) and the hook eye (50) are arranged in the middle of the curved cross members (22, 42).