Load cell for metallic silos
Disclosed is a device in the field of systems for measuring the weight of an object and in more detail concerns a load cell for metallic silos, or tanks and hoppers. The load cell for metallic silos includes: a bottom base plate for supporting it on a ground surface; a top plate for receiving and supporting a portion of a metallic silo to be weighed; a flexible element including at least one extensometer; and a spacer interposed between the bottom plate and the flexible element. Advantageously, the load cell includes a monobloc structure, substantially parallelepiped in shape, including the bottom plate, the top plate and the flexible element.
1. A load cell for metallic silos, comprising:
a bottom base plate configured to support the load call on a ground surface;
a top plate configured to receive support a portion of a metallic silo to be weighed;
a flexible element comprising at least one extensometer;
a spacer interposed between said bottom plate and said flexible element, wherein said load cell comprises a monobloc structure, comprising said bottom plate, said top plate and said flexible element,
wherein said monobloc structure comprises ground fastening means comprising four holes, arranged respectively in proximity of the four corners of said monobloc structure, and four corresponding screws, adapted to co-act stably with four corresponding threaded bushings provided in holes produced in said ground surface, and
wherein said monobloc structure is substantially parallelepiped in shape, having two longer sides and two shorter sides, and two of said four holes extend to intercept a same side of said monobloc structure, so that the load cell is easily removable from below the silos by removing only two of the screws.
2. The load cell according to claim 1 , wherein said monobloc structure comprises a first upper central portion raised in height with respect to two lateral edge strips, where said first raised upper central portion produces said top plate for receiving and supporting a portion of a metallic silo to be weighed.
3. The load cell according to claim 2 , wherein said monobloc structure comprises a first and a second groove delimiting said lateral edge strips with respect to said first raised upper central portion.
4. The load cell according to claim 1 , wherein said monobloc structure comprises a second lower central portion recessed with respect to two lateral edge strips, where said two lateral edge strips produce said bottom base plate for supporting it on said ground surface.
5. The load cell according to claim 4 , wherein said monobloc structure comprises a third and a fourth groove delimiting said lateral edge strips with respect to said second recessed lower central portion.
6. The load cell according to claim 4 , wherein the variation of height between said second recessed lower central portion and said ground surface produces said spacer.
7. The load cell according to claim 1 , wherein said monobloc structure comprises fastening means to said portion of metallic silo to be weighed comprising a plate provided with a hole, where said fastening means to said portion of metallic silo to be weighed comprise a threaded blind hole provided at the center of said first raised upper central portion and a corresponding screw, adapted to co-act with said corresponding hole provided in said plate positioned at one end of said portion of metallic silo to be weighed.
8. A load cell for metallic silos, comprising:
a flexible element comprising a raised upper central portion and a recessed lower central portion;
at least one extensometer arranged within the flexible element;
lower lateral edge strips arranged at respective opposite ends of the flexible element, the lower lateral edge strips being configured to make contact with a ground surface to which the load cell is to be secured, the recessed lower central portion being arranged between respective said lower lateral edge strips, the recessed lower central portion being recessed with respect to the lower lateral edge strips so that with the lower lateral edge strips in contact with the ground surface, the recessed lower central portion is separated from the ground surface by a space between the lower lateral edge strips; and
upper lateral edge strips arranged at respective opposite ends of the flexible element, the upper lateral edge strips being arranged on an upper side of the load cell opposite the lower lateral edge strips, the raised upper central portion being arranged between respective said upper lateral edge strips, the raised upper central portion extending to a height greater than a height of the upper lateral edge strips;
wherein with the lower lateral edge strips in contact with the ground surface, a load applied to the raised upper central portion can cause the flexible element to deflect into the space between the lower lateral edge strips, which deflection is measurable by the at least one extensometer.
9. The load cell of claim 8 , further comprising two upper grooves, each defining a boundary between a respective said upper lateral edge strip and the raised upper central portion, each of the upper grooves extending below an upper surface of the upper lateral edge strips.
10. The load cell of claim 9 , further comprising two lower grooves, each defining a boundary between a respective said lower lateral edge strip and the recessed lower central portion, each of the lower grooves extending above a lower surface of the recessed lower central portion.
11. The load cell of claim 10 , comprising two said extensometers disposed in the flexible portion, each of the extensometers being arranged at a respective end of the flexible portion, between one of the upper grooves and one of the lower grooves.
12. The load cell of claim 10 , further comprising four holes arranged respectively at four corners of the load cell, two of the holes passing through each of the upper and lower lateral edge strips, each of the holes being configured to accept a screw to secure the load cell to the ground surface by threading into a respective threaded bushing in the ground surface.
13. The load cell of claim 12 , wherein two of the holes are in the form of slots open to one side of the load cell, thereby allowing the load cell to be secured into an operating position or removed from the operating position by loosening but not fully removing two of the screws arranged in the slots, and fully removing the screws arranged in holes that are not in the form of slots.
14. The load cell of claim 8 , further comprising four holes arranged respectively at four corners of the load cell, two of the holes passing through each of the upper and lower lateral edge strips, each of the holes being configured to accept a screw to secure the load cell to the ground surface by threading into a respective threaded bushing in the ground surface.
15. The load cell of claim 14 , wherein two of the holes are in the form of slots open to one side of the load cell, thereby allowing the load cell to be secured into an operating position or removed from the operating position by loosening but not fully removing two of the screws arranged in the slots, and fully removing the screws arranged in holes that are not in the form of slots.
16. The load cell of claim 8 , wherein the overall load cell is configured as a monobloc structure having a substantially parallelepiped shape with two longer sides and two shorter sides, the upper and lower lateral edge strips being arranged along the shorter sides.
17. The load cell of claim 16 , further comprising:
two upper grooves parallel to the shorter sides of the load cell, each defining a boundary between a respective said upper lateral edge strip and the raised upper central portion, each of the upper grooves extending below an upper surface of the upper lateral edge strips; and
two lower grooves parallel to the shorter sides of the load cell, each defining a boundary between a respective said lower lateral edge strip and the recessed lower central portion, each of the lower grooves extending above a lower surface of the recessed lower central portion.
18. The load cell of claim 16 , further comprising four holes arranged respectively at four corners of the load cell, two of the holes passing through each of the upper and lower lateral edge strips, each of the holes being configured to accept a screw to secure the load cell to the ground surface by threading into a respective threaded bushing in the ground surface.
19. The load cell of claim 18 , wherein two of the holes are in the form of slots open to one side of the load cell, thereby allowing the load cell to be secured into an operating position or removed from the operating position by loosening but not fully removing two of the screws arranged in the slots, and fully removing the screws arranged in holes that are not in the form of slots.