TOOTH AND ADAPTOR FOR DREDGING MACHINE

Abstract

The tooth and adaptor for dredging machines. The tooth, attached to an adaptor, creates an assembly to deepen and clean the beds of ports, rivers, channels, etc., removing therefrom sludge, stones, sand, etc. The adaptor when attached to the blades forms the cutter head of the dredging machine. The constructive features of the coupling between the tooth and the adaptor allow improved stability between both elements, among other advantages.

Claims

1. An adaptor for attaching a tooth to the arm of a cutter head in a dredging machine, comprising a rear coupling end and a front coupling end, said front coupling end further comprising a main cavity with: a bottom end and an open end, said main cavity comprising a first upper surface, a first lower surface and two side surfaces joining both upper and lower surfaces, with the distance between the first upper surface and first lower surface decreasing towards the bottom end, side grooves, and upper and lower segments, wherein each side surface of the main cavity comprises a respective one of the side grooves with a second upper surface parallel to a second lower surface, and said second upper surface of each side groove is approximately parallel to the lower segment adjacent to the bottom end on the first lower surface and the second lower surface of the side grooves is approximately parallel to the upper segment adjacent to the bottom end on the first upper surface, and wherein a distance between the second upper surface and the second lower surface of each groove is smaller than a distance between the upper segment and the lower segment of the main cavity.

2. Adaptor, in accordance with claim 1, wherein the second upper surface is at the same level as the upper segment of the first upper surface of the cavity.

3. Adaptor, in accordance with claim 1, wherein the side walls of the cavity comprise V-shaped sides.

Description

DETAILED DESCRIPTION OF THE DRAWINGS

[0066] To complement the description being made and for the purpose of aiding to better understand the features of the invention, according to a preferred practical embodiment thereof, a set of drawings is attached as an integral part of said description which show the following with an illustrative and non-limiting character:

[0067] FIG. 1 shows a perspective view of a tooth and an adaptor prior to their coupling.

[0068] FIG. 2 shows a side view of a tooth and an adaptor prior to their coupling.

[0069] FIG. 3 shows a perspective view of a tooth.

[0070] FIG. 4 shows a plan view of a tooth.

[0071] FIG. 5 shows a side view of a tooth.

[0072] FIG. 6 shows a front view of a tooth.

[0073] FIG. 7 shows another side view of a tooth.

[0074] FIG. 8a shows a section, according to A-A, of the tooth of FIG. 7.

[0075] FIG. 8b shows a section, according to B-B, of the tooth of FIG. 7.

[0076] FIG. 8c shows a section, according to C-C, of the tooth of FIG. 7.

[0077] FIG. 9 shows a perspective view of an adaptor.

[0078] FIG. 10 shows a plan view of an adaptor. FIG. 11 shows a section, according to B-B of the adaptor of FIG. 10.

[0079] FIG. 12 shows a side view of a tooth coupled to and adaptor.

[0080] FIG. 13a shows a section, according to A-A, of the assembly of FIG. 12.

[0081] FIG. 13b shows a section, according to B-B, of the assembly of FIG. 12.

[0082] FIG. 13c shows a section, according to C-C, of the assembly of FIG. 12.

[0083] FIG. 14 shows a plan view of a tooth coupled to an adaptor.

[0084] FIG. 15 shows a section, according to A-A, of the assembly of FIG. 14.

[0085] FIG. 16 shows a section, according to B-B, of the assembly of FIG. 14.

[0086] FIG. 17 shows a tooth coupled to an adaptor showing the forces (normal, FN, and positive tangential, FT) to which the assembly might be subjected during the work of the tooth in a determined cutter turn direction.

[0087] FIG. 18 shows a prior art tooth subjected to a negative tangential force (?FT) and the reactions on the tooth to said force. The reactions on the tooth to a positive tangential force (FT) are also indicated.

[0088] FIG. 19 shows a tooth subjected to a negative tangential force (?FT) and the reactions on the tooth to said force. The reactions on the tooth to a positive tangential force (FT) are also indicated.

DESCRIPTION OF A PREFERRED EMBODIMENT

[0089] As observed in FIGS. 1 and 2, the objects of the present application, tooth and adaptor for dredging, is formed by an interchangeable tooth 10, an adaptor 20 coupled to an arm of a cutter head (not shown) of a dredging machine, and a retaining member 30 responsible for assuring the connection between the tooth and the adaptor. Said retaining member or pin 30 enters the adaptor 20 through a hole 23 and enters the tooth through a hole 13. The pin 30 goes through the tooth 10 and the adaptor 20 and is placed in a housing.

[0090] As can be observed in FIGS. 3 to 8, the tooth 10 comprises a front wear part 11 or tip of the tooth responsible for the task of tearing out the terrain, in contact with the ground and stones, and a rear coupling part or nose 12 intended for being housed in a cavity 29 arranged in an adaptor 20.

[0091] The rear coupling part 12 of the tooth 10 comprises a rear free end 16 and a forward end 19, being this forward end 19 bounded to the front wear part 11 of the tooth 10. The rear coupling part 12 has a first upper surface 123, a first lower surface 122 and two side surfaces 121 joining both upper 123 and lower 122 surfaces. Said first upper surface 123 and said first lower surface 122 comprise each at least a segment 1230, 1220 on its surface 123, 122 where both segments 1230, 1220 are approximately parallel between them. Said approximately parallel segments 1230, 1220, an upper segment 1230 on the first upper surface 123 and a lower segment 1220 on the first lower surface 122, are preferably placed adjacent to the free end 16 of the rear coupling part 12.

[0092] The nose or rear coupling part 12 of the tooth 10 is formed by a main body and an upper rib 15 centered on the upper surface 123 of said main body, increasing the section of the rear coupling part 12 where the hole 13 for the pin 30 goes through the nose 12, and being the part of the tooth that more efforts has to resist. Said rib 15 extends between a point from the upper surface 123 of the main body of the rear coupling part 12 and the place where said part 12 binds the front wear part 11. The separation between the front wear part 11 and the rear coupling part 12 is determined by two inclined planes U, D, forming an angle smaller than 90? between both and therefore determining a V shape, where the corner of the V is placed towards the tip front wear part 11 of the tooth 10, on the opposite side of the free end 16 of the rear coupling part or nose 12.

[0093] According to the previous definition of the axis x, y and z, it should be mentioned that inclined planes U and D cross themselves in axis x.

[0094] As previously explained, the upper rib 15 of the nose 12 of the tooth 10 has a shape that increases the section of the nose 12 towards the forward end 19, having the upper rib 15 a triangular or trapezoidal longitudinal section, preferably. The rib 15 will not extend along the whole distance of the nose 12 of the tooth 10, it will be shorter. The rib 15 can be narrower, smaller width, or have the same width, than the first upper surface 123 of the first main body of the nose 12 and it is centered with respect to said main body 12. The height of said rib 15 is nil in an area close to the free end 16 of the nose 12, preferably when the upper segment 1230 adjacent to the free end starts, and its height gradually increases until it reaches the wear part of the tooth 11.

[0095] On both side surfaces 121 of the main body 12, continuous side projections 14 are placed. Said projections 14 have a second upper surface 141 and a second lower surface 142 that are approximately parallel between them. The purpose of these projections 14 is help to optimize the complete stabilization of the coupling between the tooth 10 when coupled to an adaptor 20 when the same is subjected to Inverse forces. These projections 14 have its second upper surfaces 141 parallel to the lower segment 1220 on the first lower surface 122 of the main body 12 approximately and its second lower surfaces 142 approximately parallel to the upper segment on the first upper surface 1230 of the main body 12. The thickness or distance between the second upper 141 and lower 142 surfaces of the projections 14 is smaller than the distance between the upper segment 1230 of the first upper surface 123 of the main body 12 and the lower segment 1220 of the first lower surface 122 of the main body 12.

[0096] The second upper surfaces 141 of the projections 14 are preferably placed as an extension of the first upper surface 123 of the main body 12, meaning that the second upper surface 141 of the projection 14 and the first upper surface 123 of the main body 12 are placed at the same level. Anyway, instead of coinciding the upper surfaces 141 of the projections 14 with the upper surfaces 123 of the main body 12, it would be possible that the second lower surfaces 142 do coincide with the lower surface 122 of the main body 12, or even that none of the upper nor lower surfaces coincide, being in this last case the side projections 14 placed between the first upper 123 and lower 122 surfaces of the main body 12.

[0097] In the present description, when the term approximately parallel is used, it should be understood that the lines, planes or surfaces referred, could not be exactly parallel but a difference between 0? and 8? could exist between them. This difference will mainly be due to construction or fabrication restrictions that prevent the exact parallelism between the lines, planes or surfaces.

[0098] The tooth preferably comprises a stopper, with the shape of a collar, flange or perimeter projection, located on the perimeter of the tooth 10 where the front wear part 11 and the rear coupling part 12 bind. The stopper has two V-shaped sides on both sides of the tooth 10, each with a superior part 17 and a lower part 18, that coincide with the inclination of the previously mentioned planes U and D. The width between the V-shaped sides 17, 18 of the stopper is preferably larger than the distance between the sides of the projections 14 and the height or distance between the upper and lower sides of said stopper coincides with the maximum distance between the upper surface of the upper rib 15 on the main body 12 and the lower surface 122 of the main body 12. The thickness or width of said collar varies depending on the area of the tooth it surrounds and depending on the stresses to which said area is subjected.

[0099] FIG. 8a shows a section of the tooth 10 at the segment (1220 o 1230) of the nose 12, FIG. 8b shows a section of the tooth 10 at the hole 13 for the pin 30, and FIG. 8c shows a section of the tooth 10 showing the side projections 14 on the side surfaces 121 of the nose 12.

[0100] The adaptor 20, shown in FIGS. 9 to 11 is formed by a body having a rear coupling 200 at one end to be attached to an arm of the cutter head of a dredging machine and at the opposite end it has an open end 210 with a cavity 29 for receiving the rear coupling part or nose 12 of a tooth 10, which is inserted in said cavity 29. The inner surfaces, of said cavity 29 of the adaptor 20 are complementary to the surfaces of the rear coupling part or nose 12 of the tooth 10. In other words, said cavity 29 is formed by an open end 210, a bottom end 26 opposite to the previous one and bounded to the rear coupling end 200, a first lower surface 222, a first upper surface 223, and two side surfaces 221 joining both upper 223 and lower 222 surfaces. The shape of said open end 210 of the cavity 29 is defined by the shape of the two side surfaces 221 belonging to the lateral or side walls of the adaptor 20, which have an V shape with a superior part 27 and a lower part 28. Said V shape coincide with the two inclined planes U and D.

[0101] As previously described, the inner surfaces of the cavity 29 are complementary to the surfaces of the rear coupling part or nose 12 of the tooth 10.

[0102] Each of the side surfaces 221 of the cavity 29 comprises a groove 24 that extends from the open end 210 of the cavity 29 to nearly the first segment 2220, 2230 of the cavity 29, being the second upper surface 242 of the groove 24 parallel to the first segment 2220 of the first lower surface 222 of the cavity 29 and the second lower surface 241 of the groove 24 parallel to the first segment 2230 of the first upper surface 223 of the cavity 29. The distance between the second upper 242 and lower 241 surfaces of the grooves 24 is smaller than the distance between the first upper 2230 and lower 2220 segments of the cavity 29. The second upper surface 242 of the groove 24 is preferably an extension of the first upper surface 223 of the cavity 29. Anyway the grooves 24 could be placed at any level of the side surfaces 221.

[0103] As shown in FIGS. 12 to 16, the tooth 10 and adaptor 20 are coupled together by inserting the rear coupling part or nose 12 of the tooth 10 into the cavity 29 of the adaptor 20, the different complementary surfaces of the nose 12 and of the cavity 29 coming into contact with one another.

[0104] In FIGS. 13a to 13c, the matching of the different contact surfaces along the rear coupling part or nose 12 of the tooth 10 and the cavity 29 of the adaptor 20 can be seen. FIG. 13a shows a section where it can be seen the coupling between the projections 14, with its upper 141 and lower 142 surfaces, and the grooves 24, with its upper 242 and lower 241 surfaces.

[0105] FIG. 13b shows a section of the assembly where the pin goes through both members.

[0106] FIG. 13c shows the section near to the free end 16 of the nose 12, where the first segment 1230, 1220 of the first upper 123 and lower 122 surfaces of the nose 12 of the tooth 10 are parallel with the first segment 2230, 2220 of the first upper 223 and lower 222 surfaces of the cavity 29 of the adaptor 20. The side surfaces 121 of the nose 12 are parallel to the side surfaces 221 of the cavity 29.

[0107] FIGS. 15 and 16 show different longitudinal sections of the coupling between a tooth 10 and an adaptor 20 according to the present invention. In particular it can be seen the different contact surfaces between both members and in FIG. 16 it can be seen that the second upper surface 141 of the projection 14 is at the same level of the first segment 1230 of the first upper surface 123 of the nose 12 of the tooth. The same happens with the complementary surfaces of the groove and the segment 2230 of the upper surface 223 of the cavity 29.

[0108] Once the adaptor 20 has been attached through its rear coupling end 200 in the arm of the cutter head of the suction cutting dredger, the tooth 10 is coupled to the adaptor using for that purpose a preferably hammerless retaining member 30, i.e. a member that does not require the action of a mallet or hammer for removing it from or inserting it in the housings intended for such purpose in the tooth and in the adaptor. The retaining system is preferably vertical, being inserted and removed through the upper part of the tooth and of the adaptor, going through the rear coupling part or nose 12 of the tooth 10 and the adaptor 20 through respective through holes 13, 23.

[0109] Once the assembly is coupled, as previously describe, and during the working operations, the tooth 10 is subjected at its tip to different forces. Said forces make that reactions forces with orthogonal components appear on said tip: [0110] Normal force or radial force: in a same direction of the imaginary line between the center line of the cutter head and the point of the tooth, applied on a normal surface. [0111] Tangential force: perpendicular to the normal force and applied on the working surface of the tooth. Parallel to the ground. [0112] Lateral force: Mainly caused by the interaction of neighboring cuts.

[0113] As already described, the teeth and adaptors are ready to be stabilized to resist the normal, and tangential forces. The unexpected inverse forces in prior art solutions make some of the components of the assembly move or even break, therefore showing that the assembly is not completely stabilized against all the possible reaction forces.

[0114] Once the tooth and the adaptor have been coupled the assembly is ready to work on the cutter head. When the point of the tooth is subjected to tangential forces, the surfaces where reactions are created, to equilibrate said forces, are the first segment on the lower surface of the tooth and the upper surface of the main body of the nose, near the forward end 19 of the main body. With these contact surfaces between the tooth and the adaptor the tangential forces are counteracted to resist the efforts and diminish the strain in critical points of the assembly as well as in the pin.

[0115] However, when the unexpected inverse forces appear, usually when working on hard soil, it is necessary to counteract the same and the reactions are translated to the first segment on the upper surface of the nose of the tooth and on the lower surface of the projections (FIG. 19).

[0116] Due to the projections on the tooth (and the grooves in the adaptor) placed near the center of both members, the maximum effort that has to be resisted by the coupling is placed in the neutral part of said coupling.