GUINDANI, Francesco (Via 1850, 203, SAREZZO, I-25068, IT)
| CLAIMS 1. A structure for wheels with high mechanical resistance against impulse type loads, of the type that comprises a plate (2) for fixing to a carcase to be supported, a fork (3) for the idle support of the actual wheel, and suitable pivoting means (4) that are interposed between said plate (2) and said fork (3), characterised in that said pivoting means (4) comprise a substantially vertical shaft (5) that is rigidly coupled to a substantially central hole (6) of said plate (2), at least one bell-shaped housing (7), which is integral with the shaft (5) and which is associated with the portion of said shaft (5) that protrudes downwards from the plate (2), said bell-shaped housing (7) being provided with a seat (8) for respective rolling organs (9), and at least one cover (10), which is counter-shaped with respect to said bell- shaped housing (7) and which faces it, and which is also provided with a seat (1 1) for respective rolling organs (9), said cover ( 10) being stably associated with said fork (3) for its rotatable operative support. 2. The structure for wheels according to claim 1 , characterised in that between the lower surface of said plate (2) and the upper surface of said bell- shaped housing (7) there is an elastically deformable unit (12) for cushioning and contrasting the approach of the upper surface of said bell-shaped housing (7) to the lower surface of the said plate (2) in the event of impact or of dropping of the carcase to be supported. 3. The structure for wheels according to claim 2, characterised in that said unit ( 12) is a disc in rubber type material. 4. The structure for wheels according to claim 3, characterised in that said disc in rubber type material is made of a polymeric material, irrespectively in a compact or expanded version, selected from polyurethane, polyamide, polyethylene, polyvinylchloride, polytetrafluoroethylene, polyethylene terephthalate, polycarbonate, polyester, polystyrene, acetate, methacrylate, elastomer, polypropylene and combinations thereof. 5. The structure for wheels according to claim 3, characterised in that said disc in rubber type material is made of a polymeric material that has a hardness value comprised between 40 and 100 Shore A, with a preferred value of 90 Shore A. 6. The structure for wheels according to claim 1 , characterised in that said unit (12) is a spring of a type that is selected between helicoid springs, Belleville spring washers, gas springs and laminar springs. 7. The structure for wheels according to one or more of the preceding claims, characterised in that it comprises, below said cover (10), a respective raceway (13) that is stably associated with the end of said shaft (5), said raceway (13) facing toward and being proximate to a respective lower shaping (14) of said cover ( 10), between said raceway (13) and said shaping (14) of said cover (10) rolling organs (9) being interposed. 8. The structure for wheels according to one or more of the preceding claims, characterised in that said cover (10) is scarved between said bell- shaped housing (7) and said raceway ( 13), with the interposition of respective layers of rolling organs (9), following the tightening of a respective threaded sleeve (15) onto the end of said shaft (5), said sleeve (15) being provided with an abutment rim (16) for said cover (13) and said bell-shaped housing (7). 9. The structure for wheels according to one or more of the preceding claims, characterised in that between said abutment rim (16) and said raceway (13) and said bell-shaped housing (7), respective layers of elastically deformable material are interposed. 10. The structure for wheels according to one or more of the preceding claims, characterised in that, between said upper plate (2) and said carcase to be supported, at least one sheet of elastically deformable material is interposed. |
Technical Field
The present invention relates to a structure for wheels with high mechanical resistance against impulse type loads.
Background Art
The adoption of idle wheels, generally pivoting, under the bottoms of bins and items of furniture is widely known, in order to make it easier for operators to move them.
In particular, bins for refuse collection must be easily movable in order to correctly align them with the vehicle that is used to periodically empty them.
Similarly, one can think to the items of furniture used to set up trade fair stands (cabinets, but also outfitted partition walls), which need to be easily installed and just as easily removed: in this case the transfer on wheels facilitates operations.
Often, wheels are damaged as a result of an impulse type load: for example, for bins, it can happen that the vehicle, after performing the emptying operation, unloads the bin too quickly and, therefore, at the moment of impact, the wheel is subjected to the entire weight of the bin (in some cases it almost equates to the free-falling of the bin). For an item of furniture, instead, it can happen that during the transfer, the wheel may encounter steps or holes in the terrain: if these are encountered at speed, the impact is often massive and sufficient to damage the wheel beyond repair.
The use of greatly over-dimensioned wheels, to ensure that such stresses are easily withstood, is widely known.
Such construction choice brings an increase in manufacturing costs and, often, a dimensional incompatibility with wheels of standardised dimensions for the specific destination application.
Without doubt this brings with it a greater applicative difficulty because it is not possible to replace only the damaged wheel but it is necessary to replace the entire train of wheels that are mounted on the same structure (be it a bin or other receptacle, or an item of furniture).
Moreover, the increase in the weight burdens the wheel even further when the vehicle releases the bin: in fact, the greater weight of the entire bin translates to a greater force of impact for the wheels on the ground.
Disclosure of the invention
The aim of the present invention is to solve the above mentioned drawbacks, by providing a structure for wheels with high mechanical resistance against impulse type loads that has reduced size and weight.
Within this aim, an object of the invention is to provide a structure for wheels with high mechanical resistance against impulse type loads that is adapted to tolerate impacts, including high intensity impacts, against rigid surfaces without undergoing permanent deformations.
Another object of the invention is to provide a structure for wheels with high mechanical resistance against impulse type loads that is adapted to be applied to any bin or other receptacle or item of furniture, also as a replacement for traditional types of wheel.
A further object of the present invention is to provide a structure for wheels with high mechanical resistance against impulse type loads that has a low cost, is easily and practically implemented, and safely applied.
This aim, as well as these and other objects which will become better evident hereinafter, are achieved by a structure for wheels with high mechanical resistance against impulse type loads, of the type that comprises a plate for fixing to a carcase to be supported, a fork for the idle support of the actual wheel, and suitable pivoting means that are interposed between said plate and said fork, characterised in that said pivoting means comprise a substantially vertical shaft that is rigidly coupled to a substantially central hole of said plate, at least one bell-shaped housing, which is integral with the shaft and which is associated with the portion of said shaft that protrudes downwards from the plate, said bell-shaped housing being provided with a seat for respective rolling organs, and at least one cover, which is counter- shaped with respect to said bell-shaped housing and which faces it, and which is also provided with a seat for respective rolling organs, said cover being stably associated with said fork for its rotatable operative support.
Brief description of the drawings
Further characteristics and advantages of the invention will become better apparent from the description of a preferred, but not exclusive, embodiment of the structure for wheels with high mechanical resistance against impulse type loads according to the invention, illustrated by way of a non-limiting example in the accompanying drawings, wherein:
Figure 1 is an exploded perspective view of a structure for wheels with high mechanical resistance against impulse type loads according to the invention;
Figure 2 is a front view of a structure for wheels with high mechanical resistance against impulse type loads according to the invention;
Figure 3 is a sectional view, taken along the line III-III of Figure 2, of a structure for wheels with high mechanical resistance against impulse type loads according to the invention;
Figure 4 is a perspective view of a structure for wheels with high mechanical resistance against impulse type loads according to the invention.
Ways of carrying out the invention
With reference to the figures, the reference numeral 1 generally designates a structure for wheels with high mechanical resistance against impulse type loads.
The structure 1 comprises a plate 2 for fixing to a carcase or structure to be supported, a fork 3 for the idle support of the actual wheel and suitable pivoting means 4 that are interposed between the plate 2 and the fork 3.
The pivoting means 4 comprise a shaft 5 that is substantially vertical (when the structure 1 is in the configuration for use) and which is rigidly coupled to a substantially central hole 6 of the plate 2.
The head of the shaft 5 is enlarged, with a shape that is substantially complementary to a perimetric groove of the hole 6: in the assembly configuration the head of the shaft 5 is accommodated inside such groove and is rigidly locked in it, while the cylindrical body of the shaft 5 protrudes downwards to the plate 2, passing through it by means of the hole 6.
At least one bell-shaped housing 7, which is integral with the shaft 5, is associated with the portion of such shaft that protrudes downwards from the plate 2; the bell-shaped housing 7 is provided with a seat 8 for respective rolling organs (in the embodiments shown in the accompanying figures, these are spheres 9, but the adoption of different rolling elements is not, however, excluded).
At least one cover 10, which is counter-shaped with respect to the bell-shaped housing 7 and which faces it, is also provided with a seat 1 1 for respective rolling organs (for example the spheres 9).
The cover 10 is in turn stably associated with the fork 3 for its rotatable operative support.
In particular, according to the embodiment shown in the accompanying figures, the cover 10 and the fork 3 are made monolithically by mechanical deformation (and/or other equivalent processing techniques) of the top of the fork 3.
According to an embodiment that is of undoubted practical and applicative interest, between the lower surface of the plate 2 and the upper surface of the bell-shaped housing 7 there is an elastically deformable unit 12 for cushioning and contrasting the approach of the upper surface of the bell-shaped housing 7 to the lower surface of the plate 2 in the event of impact or of dropping of the carcase to be supported.
The unit 12, according to an embodiment that is of undoubted practical and applicative interest, and which is shown purely for the purposes of example in the accompanying figures, is a disc made of rubber type material.
In particular, such disc in rubber type material is made of a polymeric material, irrespectively in a compact or expanded version, preferably selected from polyurethane, polyamide, polyethylene, polyvinylchloride, polytetrafluoroethylene, polyethylene terephthalate, polycarbonate, polyester, polystyrene, acetate, methacrylate, elastomer, polypropylene and combinations thereof.
However, the adoption is not excluded of discs that are constituted by a stacking of layers of different materials so as to selectively exploit the mechanical properties of each of them.
It should be noted that the disc in rubber type material is preferably made of a polymeric material that has a hardness value comprised between 40 and 100 Shore A (the value of 100 Shore A constitutes the upper limit of hardness identified by this scale): in a possible practical application that is adapted to the provision of structures 1 for wheels that are particularly solid and resistant, the polymeric material adopted to provide the unit has a preferred hardness value that is substantially equal to 90 Shore A.
According to a possible alternative embodiment, the unit can be constituted by a spring of a type that is preferably selected from helicoid springs, Belleville spring washers, gas springs and laminar springs.
However, the possibility is not excluded of adopting a unit that is composed of a polymeric disc and a spring that are coaxial with each other, and which cooperate in the phase of dampening the mechanical stresses to which the wheel and hence the structure 1 are subjected.
The structure 1 , moreover, comprises, below the cover 10, a respective raceway 13 which is stably associated with the end (the lower end, in the assembly configuration) of the shaft 5.
The raceway 13 faces and is proximate to a respective lower shaping 14 of the cover 10.
In order to minimise the friction during the rotation of the structure 1 with respect to the shaft 5, between the raceway 13 and the shaping 14 of the cover 10, suitable rolling organs (for example the spheres 9) are interposed.
The cover 10, in the assembly configuration, is scarved between the bell-shaped housing 7 and the raceway 13, with the interposition of respective layers of rolling organs 9, following the tightening of a respective threaded sleeve 15 onto the end of the shaft 5.
The sleeve 15, in order to achieve such tightening, is provided with an abutment rim 16 for the raceway 13 and the bell-shaped housing 7.
It should be pointed out that, positively, respective layers of elastically deformable material can be interposed between the abutment rim 16 and the raceway 13 and between the rim 16 and the bell-shaped housing 7: this embodiment ensures a further dampening of vibrations and of impulse type mechanical stresses.
Similarly, between the upper plate 2 and the carcase to be supported, at least one sheet of elastically deformable material can be usefully interposed: this sheet also ensures a dampening of impulse type stresses.
The fact that the bell-shaped housing 7 is separated from the plate 2, unlike what happens in all the structures for wheels of known types, ensures that the intrinsic elasticity of these two components, during any impulse type stress, dampens the extent of such stress which will then be discharged onto the shaft 5 and onto the carcase (in particular, onto the respective elements for fixing the plate 2 to the carcase).
Then, by interposing the unit 12, the separation of the plate 2 and the bell-shaped housing 7, in terms of transmission of mechanical stresses, will be further increased, so ensuring that only a part of the energy of the impulse type stress is transferred to the shaft 5 and to the elements for fixing the plate 2 to the carcase.
In practice it has been found that the invention achieves the above aim and objects, by providing a structure 1 for wheels with high mechanical resistance against impulse type loads that has reduced size and weight. Advantageously, the structure 1 is adapted to tolerate impacts, including high intensity impacts, against rigid surfaces without undergoing permanent deformations.
Positively, the structure 1 is adapted to be applied to any bin or other receptacle or item of furniture, also as a replacement for traditional types of wheel.
It is important to emphasise that the structure 1 is of low cost and is at the same time relatively simple in terms of practical implementation: it is therefore a component that can be effectively and safely applied.
The invention thus conceived is susceptible of numerous modifications and variations, all of which are within the scope of the inventive concept. Moreover, all the details may be substituted by other, technically equivalent elements.
In the embodiments illustrated, individual characteristics shown in relation to specific examples may in reality be interchanged with other, different characteristics, existing in other embodiments.
In addition, it should be noted that anything found to be already known during the patenting process is understood not to be claimed and to be the subject of a disclaimer.
In practice the materials employed, as well as the dimensions, may be any according to requirements and to the state of the art.
Where the technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly, such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.