EP3268570B1

EP3268570B1 - Excavating head

Info

Publication number: EP3268570B1
Application number: EP16717704.7A
Authority: EP
Inventors: Silvano PALMIERI
Original assignee: Palmieri SpA
Current assignee: Palmieri SpA
Priority date: 2015-03-12
Filing date: 2016-03-11
Publication date: 2019-05-08
Anticipated expiration: 2036-03-11
Also published as: EP3268570A1; WO2016142908A1

Description

Technical Field

The present invention relates to an excavating head.

Background Art

With reference to the sector of the construction of large works such as tunnels, mines, ventilation shafts and mineral passages and the like, excavating heads are known designed to work in an ascending direction.
The heads of known type are usually operated in rotation by means of a driving machine, which makes them rotate around a vertical axis gradually as the excavation progresses upwards, and are called "raise boring".
In detail, heads are in use having a plate-shaped body with an upper face with a plurality of excavation tools arranged staggered with respect to the latter, i.e., which are mounted on the plate-shaped body projecting upwards.
Each excavation tool is idly mounted on the plate-shaped body and driven in rotation, by means of the movement and the pressure of the plate-shaped body itself, against the material to be excavated.
However, these heads of known type have some drawbacks among which must be included the fact that the excavated material accumulates in the space between the upper face of the plate-shaped body and the lower portion of the excavation tools, resulting in the stop and/or rapid wear of the excavation tools themselves.
It is easy to understand how any maintenance and replacement operations involving the excavation tools, due to the rapid wear of the latter, imply additional costs which are not negligible.
At the same time, it is also easy to understand that the heads of known type are characterized by a not very high productivity, due to the stop of the excavation tools, which greatly affects the overall speed of excavation and which leads to long working times.
Others excavating heads are known from WO 80/01587 , WO2014/078660 , WO 98/03765 , US4 784 438 and AU 747 836 .

Description of the Invention

The main aim of the present invention is to devise an excavating head which allows reducing the wear of the excavation tools and consequently cutting maintenance and replacement costs. This aim is achieved by means of an excavating head provided with the features specified in claim 1.
Another object of the present invention is to devise an excavating head which allows increasing the overall speed of excavation, considerably reducing working times and increasing productivity.
A further object of the present invention is to devise an excavating head which allows to overcome the mentioned drawbacks of the prior art within the ambit of a simple, rational, easy, effective to use and affordable solution.
The above mentioned objects are achieved by the present excavating head having the characteristics of claim 1.

Brief Description of the Drawings

Other characteristics and advantages of the present invention will become better evident from the description of a preferred, but not exclusive, embodiment of an excavating head, illustrated by way of an indicative but non-limiting example in the accompanying drawings, wherein:

Figure 1 is an exploded view of the head according to the invention;
Figure 2 is an exploded view from another angle of the head according to the invention;
Figure 3 is an axonometric view from above of the head according to the invention;
Figure 4 is an axonometric view from below of the head according to the invention;
Figure 5 is a front view of the head according to the invention.

Embodiments of the Invention

With particular reference to such figures, reference number 1 globally indicates an excavating head.
The head 1, in particular, allows performing dry excavations.
In the context of this treatise by "dry excavations" are meant excavations that take place in the absence of water, or in terrestrial conditions in the absence of water tables.
The head 1 comprises a plate-shaped body 2 having a first main face 3 and a second main face 4 opposite to each other.
With reference to the particular embodiment shown in the illustrations, the first main face 3 is facing to the excavation front.
In the context of this treatise by "excavation front" is meant the margin defined by the material to be excavated, along the direction of excavation 5 defined by a central axis 6 of the head 1.
Preferably, the central axis 6 is vertical and the direction of excavation is upwards.
Advantageously, the plate-shaped body 2 is substantially perpendicular to the central axis 6.
Furthermore, it is specified that in the present treatise expressions such as "high", "low", "upper", "lower", "above", "below" and the like, are to be deemed with reference to an operative configuration wherein the head 1 is used for upward vertical excavations.
However, it cannot be ruled out that the direction of excavation 5 be horizontal, in which case the head 1 is used in an operative configuration wherein the central axis 6 is horizontal.
In the operative configuration, shown in the illustrations, wherein the central axis 6 is vertical, the plate-shaped body 2 is substantially horizontal and the first main face 3 is above the second main face 4.
With reference to the particular embodiment shown in the illustrations, the plate-shaped body 2 has a substantially circular perimeter.
It is specified that, in the present treatise, by the term "perimeter" is meant an imaginary circumference arranged on the margin 7 of the plate-shaped body 2. The head 1 comprises an attachment element 8 to a driving machine to place the head itself in rotation.
The placing in rotation of the head 1 takes place along the direction of excavation 5, around the central axis 6.
With reference to the particular embodiment shown in the illustrations, the attachment element 8 has a substantially tubular shape and coincides with the central axis 6.
Advantageously, the attachment element 8 has a first extremity 9 for the connection to the driving machine and a second extremity 10 joining to the plate-shaped body 2.
In the present case, the first extremity 9 can be coupled to a corresponding coupling element 11, such as, e.g., a telescopic arm, equipping the driving machine.
The second extremity 10 comprises a flanged plate that is connectable to an attachment flange 12 associated with the second main face 4.
In this regard, it is pointed out that the first main face 3 is directed towards the first extremity 9 and the second main face 4 is directed towards the second extremity 10.
In detail, the flanged plate 10 is connected to the attachment flange 12 by means of joining elements 13 of the type of screws, bolts or the like, which can be fitted into corresponding bolting holes 14 equipping the attachment flange 12. Conveniently, the attachment flange 12 is associated with the second main face 4 by interposition of a plurality of reinforcing ribs 15.
Furthermore, the head 1 comprises a central hole 16 crossing the plate-shaped body 2 between the first main face 3 and the second main face 4.
With reference to the particular embodiment shown in the illustrations, the attachment element 8 is housed at least partly in the central hole 16 so as to cross the plate-shaped body 2 from side to side, so that the first extremity 9 emerges from the first main face 3 and the second extremity 10 emerges from the second main face 4.
The head 1 comprises at least an excavation tool 17 associated with the plate-shaped body 2 so as to protrude at least in part from the first main face 3. Advantageously, the plate-shaped body 2 comprises a plurality of excavation tools 17.
The excavation tools 17 have variable shape and size according to the type and dimensions of the excavation.
With reference to the particular embodiment shown in the illustrations, the excavation tools 17 are composed of a substantially cylindrical or frusto-conical body having a sharp or abrasive outer surface.
Conveniently, the excavation tools 17 are mounted idle on the plate-shaped body 2.
In the present case, each excavation tool 17 is associated with the plate-shaped body 2 by means of axial pins 18 separate and parallel to each other which allow its free rotation around a central axis of symmetry of the excavation tool 17.
With reference to the particular embodiment shown in the illustrations, the excavation tools 17 are arranged symmetrically with respect to the central axis 6 and have rotation axes with different inclinations according to their position on the plate-shaped body 2.
It cannot however be ruled out that the aforementioned excavation tools 17 be arranged asymmetrically with respect to the central axis 6.
Advantageously, the excavation tools 17 define an excavation plane 19 tangent to the excavation tools themselves.
The excavation plane 19, in practice, consists in an imaginary plane which, in the operative configuration of the head 1, is substantially horizontal and tangent to the upper part of each excavation tool 17.
Furthermore, the head 1 comprises at least a through opening 20 and crossing the plate-shaped body 2 between the first main face 3 and the second main face 4, within which a corresponding excavation tool 17 is at least partially housed. Advantageously, the head 1 which comprises a plurality of excavation tools 17, also comprises a plurality of through openings 20, wherein each excavation tool 17 is at least partially housed within one of the through openings 20.
In particular, each excavation tool 17 is at least partially housed within one and only one corresponding through opening 20 and emerges (i.e. protrudes) from the first main face 3 for at least one-twentieth of its volume.
Advantageously, the axial pins 18 of the excavation tools 17 are arranged inside the through openings 20 and the material excavated by the excavation tools 17 is able to cross the plate-shaped body 2, passing in the space defined between the excavation tools 17 and the inner walls of the through openings 20.
It is easy to appreciate how the presence of the through openings 20 in which the excavation tools 17 are housed facilitates the fall of the excavated material, determining an increase in the flow rate of the exiting material and an increase in the speed of excavation, in addition to averting the risk of the excavated material accumulating between the excavation tools 17 and the plate-shaped body 2.
The head 1 comprises at least a through slot 21a, 21b crossing the plate-shaped body 2 between the first main face 3 and the second main face 4 and which is shaped by the excavation tools 17.
Advantageously, the head 1 comprises a plurality of through slots 21a, 21b.
With reference to the particular embodiment shown in the illustrations for example, the through slots 21a, 21b comprise a plurality of first through slots 21a having a substantially open first edge 22a and a plurality of second through slots 21b having a substantially closed second edge 22b.
Advantageously, the first through slots 21a are formed on the perimeter of the plate-shaped body 2, whereas the second through slots 21b are spaced apart with respect to the perimeter of the plate-shaped body 2.
With reference to the particular embodiment shown in the illustrations, the first through slots 21a are obtained from a recess of the substantially circular perimeter of the plate-shaped body 2, whereas the second through slots 21b have a substantially circular shape.
Advantageously, the through slots 21a, 21b are arranged symmetrically with respect to the central axis 6.
Nonetheless, alternative embodiments cannot be ruled out wherein the above-mentioned through slots 21a, 21b are asymmetrically arranged with respect to the central axis 6.
It is easy to appreciate how the presence of the through slots 21a, 21b contributes to obtaining a fast evacuation of the excavated material and facilitates its expulsion by gravity.
The operation of the present invention is as follows.
The head 1 is made to rotate by the operation of the driving machine.
The excavation tools 17 are operated in rotation by means of the pressure of the head 1 against the excavation front.
Simultaneously the excavated material, passing through the through openings 20 and the through slots 21a, 21b comes out by gravity downwards in the direction opposite the direction of excavation 5.
It has in practice been ascertained how the described invention achieves the intended objects.
In particular, the fact is underlined that the particular solution of providing a plurality of through openings, formed through the plate-shaped body and housing the excavation tools, permits increasing the amount of material exiting in the unit of time and greatly increases the productivity of the excavating head.

Claims

Excavating head (1) comprising:
- at least an attachment element (8) to a driving machine to place said head (1) in rotation;

- at least a plate-shaped body (2) connected to said attachment element (8) and having at least a first main face (3) and at least a second main face (4) opposite to each other, said first main face (3) being facing to the excavation front; and

- at least an excavation tool (17) associated with said plate-shaped body (2) so as to protrude at least in part from said first main face (3);

- least a through opening (20) and crossing said plate-shaped body (2) between said first main face (3) and said second main face (4), said excavation tool (17) being at least partially housed within said through opening (20);
characterized by the fact that said attachment element (8) has a first extremity (9) for the connection to said driving machine, said first main face (3) being directed towards said first extremity (9).
Head (1) according to claim 1, characterized by the fact that said excavation tool (17) emerges from said first main face (3) for at least one-twentieth of its volume.
Head (1) according to one or more of the preceding claims, characterized by the fact that it comprises a plurality of said through openings (20) and a plurality of said excavation tools (17), each of which is at least partially housed within one of said through openings (20).
Head (1) according to one or more of the preceding claims, characterized by the fact that said plate-shaped body (2) has a substantially circular perimeter and is substantially perpendicular to a central axis (6).
Head (1) according to one or more of the preceding claims, characterized by the fact that said attachment element (8) has a substantially tubular shape and coincides with said central axis (6).
Head (1) according to one or more of the preceding claims, characterized by the fact that said attachment element (8) has a second extremity (10) joining to said plate-shaped body (2), said second main face (4) being directed towards said second extremity (10).
Head (1) according to one or more of the preceding claims, characterized by the fact that said second extremity (10) comprises a flanged plate that is connectable to an attachment flange (12) associated with said second main face (4).
Head (1) according to one or more of the preceding claims, characterized by the fact that said attachment flange (12) is associated with said second main face (4) by interposition of a plurality of reinforcing ribs (15).
Head (1) according to one or more of the preceding claims, characterized by the fact that it comprises a central hole (16) and crossing said plate-shaped body (2) between said first main face (3) and said second main face (4), said attachment element (8) being housed at least partly in said central hole (16) so as to cross from side to side said plate-shaped body (2) with said first extremity (9) that emerges from said first main face (3) and said second extremity (10) that emerges from said second main face (4).
Head (1) according to one or more of the preceding claims, characterized by the fact that it comprises at least a through slot (21a, 21b) and crossing said plate-shaped body (2) between said first main face (3) and said second main face (4), said through slot (21a, 21b) being clear of said excavation tools (17).
Head (1) according to one or more of the preceding claims, characterized by the fact that said through slot (21a, 21b) has a substantially open edge and is formed on said perimeter of the plate-shaped body (2).
Head (1) according to one or more of the preceding claims, characterized by the fact that said through slot (21a, 21b) has a substantially closed edge and is spaced apart with respect to said perimeter of the plate-shaped body (2).