WO2020095265A1

WO2020095265A1 - Self-leveling support structure and related container

Info

Publication number: WO2020095265A1
Application number: PCT/IB2019/059618
Authority: WO
Inventors: Valentino Orrigoni
Original assignee: Dante Bertoni S.R.L.
Priority date: 2018-11-09
Filing date: 2019-11-08
Publication date: 2020-05-14
Also published as: IT201800010203A1

Abstract

The present disclosure provides a structure of self-leveling support comprising a base (1) of elongated shape with a greater longitudinal dimension of a transverse dimension, at least two lower rods (2) hinged on the base in longitudinally opposite positions of the base, longitudinally oriented to the base so as to remain projectively above the base, an upper platform (3), having said elongated shape, defining a support surface for objects and/or loose materials, at least two upper rods (4), hinged at longitudinally opposite positions of the upper platform at an opposite surface to said supporting surface, and at least two torsion springs (5), wherein each lower rod of said lower rods is hinged to a respective upper rod of said upper rods by means of a respective torsion spring of said torsion springs. This support structure can be incorporated in an external body (6) to make a container or a trolley with a self-leveling platform..

Description

SELF-LEVELING SUPPORT STRUCTURE AND RELATED CONTAINER

TECHNICAL FIELD

The present disclosure relates in general to trolleys and more particularly to an internal structure with a self-leveling upper platform for a containing trolley with a self-leveling sliding internal platform.

TECHNOLOGICAL BACKGROUND

In industrial establishments such as, for example, industrial laundries, textile factories and the like, the use of trolleys for transporting materials is known. These trolleys generally comprise a base and a perimetric wall connected thereto. The trolleys for transporting materials are also generally provided with a plurality of fixed or orientable wheels, mounted under the base.

A trolley for transporting materials may have different shapes depending on the intended use, for example a polygonal or cylindrical shape. Still according to use, the various parts of the trolley may be made with different materials, such as, for example, galvanized sheet metal, aluminum, thermoplastic materials, and so on. Thermoplastic materials are currently widespread because they are very cheap and resistant.

Trolleys for the transport of structurally similar materials are also commonly used in hotels, hospitals and communities, for example for transporting linen to floors or in airplanes for the delivery and collection of various materials such as pillows and blankets, or even for storing stacked dishes or glasses and cups in respective baskets superimposed on each other.

The so-called self-leveling trolleys, for example those used in kitchens as dish dispensers, have a lifting platform which is raised or lowered automatically as objects are stacked on top of it or are removed, so that the object at the top of the stack is practically at the same level as the top edge of the trolley. Typically these trolleys, especially those with a simpler structure, have an upper platform, possibly perforated, which defines a support surface of objects, and which is supported by at least one moll in that, at rest, supports it at a distance from the base. To guide the up and down movements of the upper platform, there are pantograph mechanisms fixed on the sides of the platform. As objects are deposited on the upper platform, the weight of the objects makes the platform lower by folding the pantograph mechanisms. Vice versa, by removing objects from the upper platform, the load is lightened and the spring lifts the platform, making the pantograph mechanisms unfold.

A drawback of this type of trolleys is that it is not expedient to realize them so as to have an upper platform of oblong shape, for example rectangular with two opposite sides much shorter than the other two sides. Indeed, the pantograph mechanisms connected to the shorter sides must necessarily have shorter rods and in greater number than the pantograph mechanisms connected to the longer sides, so as not to get stuck against the external walls of the trolley. Consequently, when they are in a completely folded configuration, the greater the number of arms that compose these pantograph mechanisms, the greater their minimum height. This minimum height reduces the useful stroke of the upper platform and consequently the actual capacity of the trolley. For this reason, generally the trolleys of this type, with a pantograph mechanism, have a self- leveling upper platform of substantially squat shape, so as to limit, as far as possible, the reduction in capacity due to the minimum height of the pantograph mechanisms when completely folded.

Unfortunately, in textile factories it would be preferable to use trolleys with an elongated self-leveling upper platform, which are better suited to collect a semi-finished or finished product, which can be deposited on an elongated platform with a simple alternative movement, whereas instead a semi-finished or finished product should be carefully distributed to evenly weigh on a squat-shaped platform.

It would be desirable to have a cart with an elongated self-leveling upper platform, made using simple pantograph elevator mechanisms, not burdened however by limitations to the capacity of the trolley due to the minimum height of the pantograph in the folded configuration.

SUMMARY

To obviate these drawbacks, a self-leveling support structure has been devised which has a base, rods, preferably in the form of tubular elements, and springs, and a platform which defines a supporting surface which may be lowered until it rests on the base, thus minimizing the footprint of the structure at full load.

More precisely, the structure comprises a base of elongated shape with a greater longitudinal dimension than a transverse dimension, at least two lower rods hinged to the base in longitudinally opposite positions of the base, oriented along the longitudinal direction of the base so as to remain projectively over the base, an upper platform of elongated shape, defining a support surface for objects and/or loose materials, at least two upper rods, hinged in longitudinally opposite positions of the upper platform at a surface opposite the supporting surface, and at least two torsion spring, wherein each lower rod is hinged to a respective upper rod by means of a respective torsion spring. According to one aspect, the rods are in the form either of tubular elements or solid bars.

This support structure may be incorporated in an outer shell to make a container or a trolley with a self-leveling platform.

Preferred embodiments are defined in the dependent claims.

All claims as filed are an integral part of this description and are herein incorporated by reference.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a profile view of a structure with a self-leveling platform according to this disclosure.

Figure 2 corresponds to Figure 1 with the platform represented in semi-transparency. Figure 3 is a side view of the structure of Figure 2 with the platform shown in semi transparency.

Figure 4 shows a container incorporating the structure of Figure 2 with the platform, shown in semi-transparency, which emerges beyond the edges of the external body of the container.

Figure 5 shows a container incorporating the structure of Figure 2 with the platform, shown in semi-transparency, at about half of the useful stroke.

Figure 6 shows a container incorporating the structure of Figure 2 with the platform, shown in semi-transparency, lying on the bottom of the container and hiding under it the rods (the tubular elements) of the structure.

DETAILED DESCRIPTION

A structure with a self-leveling platform for a container according to this disclosure is schematically shown in Figure 1 and in the semi-transparent views of Figures 2 and 3. It substantially comprises a base 1 of substantially elongated shape, for example rectangular, with a longitudinal dimension greater than a transverse dimension. Above the base 1 two lower rods 2 have respective first ends hinged at diametrically opposite positions of the base 1, oriented in the longitudinal direction so as to be able to have a relatively great length without colliding against the walls of the shell of the container in which the structure will be installed.

The structure has an upper platform 3 on which the objects to be transported will be placed. Below the upper platform 3, two upper rods 4 are hinged, in diametrically opposite positions of the upper platform 3 substantially in front of the respective lower rods 2. A second end opposite the respective first end of each lower rod 2 is connected to a second end opposite the respective first end of the respective upper rod 4 by means of a respective torsion spring 5. The torsion spring 5 may be obtained for example by spirally curving a piece of steel wire. The two opposite free ends of the spirally curved steel wire of a torsion spring 5 may be respectively fixed to a respective lower rod 2 and to the corresponding upper rod 4.

According to one aspect, the lower rods 2 and the upper rods 4 are in the form of a tubular element, which typically are lighter than solid bars. In this case, a lower tubular element 2 and the corresponding upper tubular element 4 may be hinged by inserting in the lower tubular element 2 and in the corresponding upper tubular element 4 the two opposite terminal ends of the spirally curved steel wire of a torsion spring 5.

Since it is more convenient to constrain the lower tubular elements 2 to the corresponding upper tubular elements 4 by inserting therein the free ends of the respective torsion springs 5, reference will be made hereinafter to such an embodiment in which the lower rods 2 and the upper rods 4 are in the form of tubular elements. It is understood that what will be said can be repeated, mutatis mutandis , if instead of lower tubular elements 2 and upper tubular elements 4 lower solid bars 2 and upper solid bars 4 are used.

A structure of Figure 1 inserted in the shell of a container is shown in figures 4 to 6. The shell 6 of the container is shown in semi -transparency as well as the upper platform 3 to show how the configuration of the structure changes with a self-leveling platform. When the platform 3 is unloaded, the structure assumes the configuration illustrated in Figure 4, with the torsion springs 5 configured to support the weight of the platform 3. By pressing from above the upper platform 3, the platform 3 is lowered (Figures 5 and 6) reducing the angle formed between the upper tubular element 4 with the respective lower tubular element 3 and loading the respective torsion springs 5, which are biased to sustain the upper platform 3.

Conveniently, the torsion springs 5 will be configured so as to be substantially at rest when the upper platform 3 is at a nominal distance from the base 1, corresponding to the height of the shell 6 of the container.

In order to make easier to lift the platform 3, a pulling device 8, which can be for example a spring in tension as shown in the figure or a piston, for example an oil or gas piston, which binds together the lower tubular elements 2 (or alternatively the upper tubular elements 4), at ends opposite to those constrained to the base 1 of the structure. The pulling device 8, for example the pulling spring 8 shown in the figures, will be more distended by adding weight on the platform 3 when the latter is relatively high, i.e. when the torsion springs 5 that connect the tubular elements 2 and 4 are almost unloaded, and will be distended less by adding weight when the platform 3 is close to the lower end-of-stroke and contrasts the forces in the longitudinal direction supported by the tubular elements. In the latter situation, the torsion springs 5 that connect the lower tubular elements 2 to the respective upper tubular elements 4 are fully loaded and this avoids that the platform 3 remains stuck on the base 1 at the bottom of the container.

Unlike common pantograph mechanisms, in the structure with self-leveling platform of the present disclosure there is no need for the upper tubular elements 4 to be hinged directly between them and the lower tubular elements 2 to be hinged directly between them, but it is sufficient that the upper tubular elements 4 are hinged to respective lower tubular elements 2 by means of respective torsion springs 5, for example with free ends threaded in the tubular elements 2 and 4. An advantage of this configuration consists in the fact that, when the upper platform 3 is pushed downwards by the weight of the material placed above it, the lower tubular elements 2 and the upper tubular elements 4 recline one next to the other without overlapping as in the pantograph mechanisms, whereby the height of the stroke that the upper platform 3 can perform is maximized. In addition, it is possible to adapt the structure by simply changing the type of torsion spring 5, so as to be always self-leveling depending on the specific weight of the material to be deposited on the upper platform 3.

More in detail, the platform 3 must always be lowered by a same nominal height when a same nominal volume is placed on the platform, so that the deposited material is contained in the container and stays at the level of the upper edge of the shell 6 of the container. If on the platform 3 material with relatively small specific weight must be deposited, then the torsion springs 5 that connect the lower tubular elements 2 to the upper tubular elements 4 must have a small elastic constant so that the platform 3 is lowered to such a nominal height under the relatively low weight of the nominal volume of deposited material. Similarly, if on the platform 3 must be deposited material with a relatively great specific weight, then the torsion springs 5 that connect the lower tubular elements 2 to the upper tubular elements 4 must have an elastic constant correspondingly great so that the platform 3 is lowered always by this nominal height, this time however under the relatively great weight of the nominal volume of deposited material.

Given that the torsion springs 5 are conveniently threaded into the tubular elements 2 and 4, it becomes easy to turn a self-leveling structure intended to support materials having a great specific weight in a self-leveling structure for materials having a small specific weight, and vice versa, simply by replacing the torsion springs 5.

In order to avoid that the two torsion springs 5 may escape from the tubular elements 2 and 4, the latter will be conveniently shaped so as to end with a C-shaped yoke 7, as shown in Figure 3, so as to hold the coils of the torsion spring 5 preventing that the respective free end threaded in the tubular element can escape accidentally.

For reasons of rigidity and lightness of the structure, the upper platform 3 will preferably be made with a platform, which for example may be made of metal sheet or rigid plastic, with the edges bent downwards, as shown in the figures, so as to resist more to bending. In this case, the height of the folded side edge of the platform 3 will reduce the capacity of the container useful for containing material therein. However, this reduction is practically unavoidable since it serves to give rigidity to the platform 3 and to prevent it from bending under the weight of objects or material deposited above it. Furthermore, a reduction in the useful capacity of the container is unavoidable, as the tubular elements 2 and 4 are always below the platform 3.

Conveniently, in the container of the present disclosure the tubular elements 2 and 4, completely folded as shown in Figure 6 when the container is loaded, are thin enough to be accommodated in the space below the upper platform 3, remaining hidden under it. Preferably, the upper tubular elements 4 and lower tubular elements 2 are made of a rigid material, such as metal, preferably steel, or rigid plastic or fiber.

Conveniently, the torsion springs 5 that connect the lower tubular elements 2 to the respective upper tubular elements 4 are helical springs, as shown in figures.

A self-leveling elevating container of this disclosure can be obtained by mounting a self-leveling structure, like the one described above, inside the shell 6 of a container, so that the upper platform 3 can slide guided by the inner walls of the shell 6 fixed to the base 1.

The upper platform 3 can be made of a folded plate. The tubular elements may be of a rigid and light material, to limit the overall weight of the structure, for example of steel or of aluminum.

Thanks to the disclosed structure, it is possible to produce self-leveling elevating trolleys having an oblong shape which, with the same capacity as the current squat- shaped trolleys, are easier to store side by side and are easier to fill with produced continuously material, as in the textile industry, by depositing the material with a reciprocating movement back and forth, being certain of completely covering the lifting platform without leaving empty spaces. They can be validly used also for transporting crockery, getting rid of the current constraints that impose a squat shape on the trolleys, for example triangular equilateral or squared.

Finally, the possibility of changing the springs allows to quickly adapt the same structure according to the specific weight of the materials to be stored/transported.

Claims

1. A self-leveling support structure, including:

a base (1) having an elongated shape with a longitudinal dimension greater than a transverse dimension;

at least two lower rods (2) having respective first ends hinged on the base (1) at longitudinally opposite positions of the base (1), said lower rods (2) being oriented longitudinally to the base (1) so as to remain projectively above the base (1);

an upper platform (3), having said elongated shape, defining a supporting surface for objects and/or loose materials;

at least two upper rods (4), having respective first ends hinged at longitudinally opposite positions of the upper platform (3) on a surface opposite to said supporting surface;

at least two torsion springs (5), wherein a second end opposite to the first end of each lower rod of said lower rods (2) is hinged to a second end opposite to the respective first end of a respective upper rod of said upper rods (4) by means of a respective torsion spring of said torsion springs (5).

2. The structure according to claim 1, comprising a pulling device (8) mounted so as to bind together either:

- said second ends of said lower rods (2) not hinged on said base (1), or

- said second ends of said upper rods (4) not hinged on said upper platform (3).

3. The structure according to claim 2, wherein said pulling device (8) is a pulling spring or a piston, preferably a gas or oil piston.

4. The structure according to one of the preceding claims, wherein each of said torsion spring of said springs (5):

- is realized with a spirally curved metal wire with two opposite ends;

- each one of the two opposite ends of the spiral curved metal wire is fixed to a respective lower rod of said lower rods (2) and to a corresponding upper rod of said upper rods (4), respectively.

5. The structure according to claim 4, wherein:

- said lower rods and upper rods are in the form of lower tubular element and upper tubular element, respectively; - each of the two opposite ends of the metal wire of each torsion spring (5) is respectively threaded into a respective lower tubular element of said lower tubular elements (2) and into a corresponding upper tubular element of said upper tubular element (4).

6. The structure according to claim 4 or 5, wherein each of said lower rods (2) and of said upper rods (4) has the respective second end not hinged on said base (1) or on said platform (3), and has a respective C-shaped yoke (7) inside which coils of one of said torsion springs (5) are housed.

7. The structure according to one of the previous claims, wherein said upper platform (3) is made of a plate defining said supporting surface with folded edges, the folded edges defining a height of a housing below the support surface in which to hide said rods (2, 4) and said torsion springs (5).

8. The structure according to the previous claim, wherein said plate is made of metal sheet or of rigid plastic.

9. The structure according to one of the preceding claims, wherein said upper rods

(4) and said lower rods (2) are made of a rigid material, preferably of metal, or of plastic, or of fiber, or of steel.

10. A container with self-leveling platform, including

a self-leveling support structure according to one of the previous claims;

an outer shell (6) defining containment walls, fixed perimetrically to the base (1) of the self-leveling support structure so as to surround it and so that the platform (3) of the self-leveling support structure can be raised and lowered while remaining surrounded by the outer shell (6) and guided by said containment walls.