[0001] The present invention refers to a drilling machine provided with a device for guiding
the drill rods contained in a loading device.
[0002] In particular, the present invention relates to the characteristics of the device
which allows for guiding the drill rods in their right advance direction, determined
by the inclination of the drilling which has to be carried out.
[0003] Drilling machines comprise a supporting structure comprising a guide tower (called
mast), provided with a suitable rotating head for moving the drill rods, to which are
given both the movements of advance in the ground and of successive return and which
is able to directly provide and transmit the movements of rotation.
[0004] When provided for, drill rods can be positioned in batteries and housed inside the
loading devices associated to the supporting structure. A drilling battery is generally
composed of rods with a variable length (e.g. 1m; 1,5m; 2m; 3m; 6m) which are jointed
through threaded-type couplings, for obtaining increasing drilling depths.
[0005] As a matter of fact, the guide tower is normally limited in length for containing
the size of the drilling machine and are common strokes comprised between 4 and 7
meters.
[0006] A common request in projects of foundations is obtaining excavation performances
at 20-50 meters depths, whereas specific works in geognostic field, water wells, geothermics
can require excavation depths even higher than hundred meters deep.
[0007] The vertical drilling at high depths are carried out with drilling machines which
are supplied with continuity, through the use of lifting means, which favor the movements
of the rods making these maneuvers safe and ergonomic.
[0008] One of the maneuvers required with this type of drilling machines is for instance
the one which provides for manually centering the rod among the blocking elements
(vices) positioned at the base of the guide tower, which support the rods in the hole
and are used for retaining the battery hanging from the hole and for producing the
unscrewing of two adjacent rods.
[0009] The loading devices called "rod loading devices" are integral with the machine and
have the function of bringing the rod to be inserted into the battery in proximity
of the centerline of the hole.
[0010] These devices can have different shapes, but they are generally distinguishable into
two typologies: tongs-type loading systems and revolver-type loading systems.
[0011] In the first case the rod contained in a storage container, is drawn by a remote-controlled
arm which brings the rod in the centre of the hole where it is then screwed to the
rotating head kept in position by the same loading vices.
[0012] On the contrary, in the revolver-type loading systems, the rods are stored on a container,
normally rotating, and supported by supporting elements (goblets) and centering elements
(spacers or open-section springs) which keep them in guide, inside the structure of
the loading device. The loading device is brought in the centre of the hole by a remote-controlled
arm (generally of hydraulic type), which puts the rod during the loading step in the
centre hole, and which is drawn using the movements of the rotating head itself.
[0013] These types of loading devices are generally limited in their capacities, but safe
because the rod is always mechanically supported by the lower arm of the loading device,
unlike the preceding ones where the rod may fall if the vices are not correctly tightened
or not correctly working.
[0014] When the drillings are carried out with angular inclinations with respect to the
vertical line, the revolver-type loading devices must be coupled to guide devices
which keep the rod centered in the desired direction, as the weight force of the parts,
would tend to cause deviations such to make it impossible the centering between two
adjacent rods with the consequent non-possibility of screwing them and of continuing
the drilling without the aid of manual interventions.
[0015] The centering guide is normally fixed on the guide tower, generally in fixed position,
over the height corresponding to the zone interested by the movement of the lower
arm of the loading device.
[0016] Therefore, the guide positioned at a height forcedly distant with respect to the
base (area wherein are positioned the blocking elements of the rods, commonly named
"vices") limits the effective stroke of the rotating head which cannot move down further
than the minimal height, making it lose useful stroke.
[0017] This causes, as a consequence, the realization of guide towers with strokes higher
than the required, because in presence of revolver-type loading devices which work
in inclined conditions (up to the horizontal line or even further), it is necessary
to insert the guide for centering the rods.
[0018] Obviously, this solution brings to dimensioning of the total excavation equipment
much higher than the required, with proportional cost increasing.
[0019] The present invention proposes to obviate to the above mentioned inconvenients by
realizing a drilling machine provided with a device for guiding the drill rods which
is movable along said guide tower and whose position can be always controlled. In
this way, the device can be arranged in a higher working position, when a rod has
to be positioned using the loading device, and brought in a lower position of minimal
dimensions on the guide tower, during the operations of drilling.
[0020] An aspect of the present invention relates to a drilling machine having the characteristics
of the attached claim 1.
[0021] Other characteristics of the machine according to the present invention are contained
in the attached dependent claims.
[0022] The characteristics and the advantages of the drilling machine according to the present
invention will be clearer and better highlighted by the following description, exemplificative
and non-limiting, of a form of embodiment with reference to the attached figures in
which:
- Figure 1 schematically shows a perspective view of a supporting structure of a drilling
machine provided with guide tower, with revolver-type loading device and with guide
device for the rods according to the present invention;
- Figure 2 schematically shows a perspective view of the guide device for the rods according
to the present invention;
- Figure 3 shows in perspective view a particular of figure 1 wherein it is highlighted
the guide device for the rods in position of upper loading according to the present
invention;
- Figure 4 shows in perspective view the guide device for the rods in the lower position
of minimal dimensions associated to the rotating head during the its downward movement
along the guide tower according to the present invention;
- Figure 5a, 5b and 5c show respectively in as many lateral views the guide tower, the
rod loading device and the guide device for the rods, during the loading operations
of the rods on the tower according to the present invention;
- Figures 6a and 6b schematically show an anti-rotating group associated to the revolver-type
loading device according to the present invention.
[0023] With reference to the mentioned figures the drilling machine according to the present
invention comprises a guide tower 2 provided with elements for guiding sliding 21,
upon which at least a carriage 22 of a rotating head 23 moves. Furthermore, preferably
on the same guides at least also a guide device for the rods moves , in such a way
as to aid the respect of the drilling axis X of the rod A, in the centre of the hole.
[0024] Furthermore, the machine comprises a revolver-type loading device 3 having at least
a rotating container upon which the rods are stored, formed by a couple of rotating
plates one upper 31 and one lower 32, between which are arranged, preferably parallel
among them, the rods themselves.
[0025] Upon this lower plate is preferably provided a plurality of goblets 33 (which in
figure 3 are shown more simply as a holed plate with diameters of the holes suitable
for housing and guiding the rod contained) which support rods 34 and centring elements,
which keep them in guide inside the structure of the loading device.
[0026] The loading device or the device of loading is movable between an open position,
wherein rods 34 in the loading device are positioned at the maximum distance from
rod A in the centre of the hole and a closed position wherein the drilling axis X
coincides with the one of the rod contained on the rotating drum in position of loading
or unloading from it. This movement is obtained through a lower 35 and an upper 36
couple of arms which make it able to rotate with respect to the guide tower.
[0027] Guide device 4 for the rods comprises preferably a supporting frame 41, provided
with sliding means 42 adapted to slide upon guiding elements 21 for the sliding of
tower 2, possibly provided with elements 43 for cleaning the elements themselves generally
made of rubber and with guiding and centering elements 44 for the rod, advantageously
removable, in order to be adapted to the different diameter rods.
[0028] The guide device for the rods is also provided with blocking means of the device
itself, in a predetermined working position along the guide tower. This working position
corresponds to the loading or unloading step of the rods from the loading device,
wherein it is necessary to carry out the positioning and the orientation of the rod
in the correct direction of drilling.
[0029] The guide device comprises, furthermore, means adapted to fasten to rotating head
23 when the latter is moving downwards during the operation of drilling with the rod
and reaches the guide device in said predetermined working position. When the drilling
rotating head gets in contact with the guide device, it pushes this downwards, determining
the unlock of these blocking means, and contextually it hooks solidly the guide device
to the rolling head. In this way, the head itself and the device move together downwards
hooked the one to the other along the guide tower, till the guide device reaches a
lower position of minimal overall dimensions on the tower during the drilling operations
. During the successive reascending once reached again the predetermined position,
contrasting means positioned between the guide tower and the movable guide, determine
the release of the guide device from the head and its repositioning in the working
position.
[0030] These blocking means comprise preferably at least a mechanical stop 45 contrasting
with first elastic means 46 which push said stops to insert in at least a retaining
seat 24 realized on guide tower 2 in said predetermined working position (upper).
[0031] These seats and elastic means are opportunely sized for supporting the weight of
the guide and the working stresses.
[0032] These fastening means comprise preferably at least a hook 47 which acts in contrast
with second elastic means 48 adapted to hook at least one projecting element 25 integral
with carriage 22 (not shown in Fig. 2 but visible in Fig. 4) of rotating head 23 and
to transmit the movements of shifting given by it along the guide tower.
[0033] The contrasting means comprise at least a cam 26 which directly acts on at least
a shoulder 49 of the hook or on a roller free to rotate 49A for reducing the frictions
and the consumptions between the sliding parts (cam 26 and shoulder 49), determining
its rotation around the axis Y and its release from projecting element 25 fixed to
carriage 22.
[0034] The operations of drilling in the drilling machine proceed as follows.
[0035] The movable guide is initially blocked in upper working position S with stops 45
engaged into seats 24 of the guide tower.
[0036] In the step of rod loading, after having reached the maximum depth with the rods
in battery, the loading device is closed and brought in the center of the hole in
correspondence with the loading axis coincident with the one of the excavation X.
[0037] During the closing movement the loaded rod is supported by the lower arm of the loading
device and in proximity of the excavation axis X the guide means center the rod and
keep it in position through the guide elements and rod centering elements 44.
[0038] The rotating head screws the rod to be loaded and after having tightened it, it is
lifted up by the loading device.
[0039] As the rod is no more inserted in goblets 33,the loading device can be moved away
for returning in the rest configuration, away from the excavation axis while the rod
in this step remains hanging between the rotating head and centering element 44 on
the guide.
[0040] Guide 44 has an open shape for allowing the free movement of inserting and extracting
the rod from and to the loading device and provided with elastic means which keep
the rod tightened in position by closing itself at a diameter lower than the one of
the rod to be moved.
[0041] The rotating head, while moving downwards, screws the rod to the drilling battery
and makes the drilling restart. By approaching the guide, the carriage prepares to
drag it in the lower position of minimal overall dimensions B.
[0042] Hook 47 is kept in the raised position by cam 26. When the carriage of the rotating
head approaches the structure of the guide device and begins to push it, this action
releases stops 45 from their retaining seats 24 overcoming the strength of elastic
means 46 and contemporarily the hook engages projecting element 25 fixed to carriage
22 when descending from cam 26.
[0043] From this moment, the carriage solidly drags the guide device, by accompanying it
from an upper position to a lower one, controlling the position in both the movement
directions.
[0044] Having reached the lower position of minimal overall dimensions B the drilling is
completed and a new rod can be loaded.
[0045] After having removed the drilling battery from rotating head 23, by using the vices
and leaving it hanging from them, according to the standard and known practices, therefore
here not described, it can be started the reloading step of a new rod.
[0046] In the movement of return or reascending, the carriage brings back the guide device
toward upper position S. Stops 45 are the first to engage in retaining seats 24 and
then hook 47, pushed by the cam it lifts up releasing the guide device from carriage
22.
[0047] Now the guide device is released in upper position A remaining locked in this position
up to the successive loading. For the correct functioning of the mechanism it is essential
to position the elements integral with the guide tower (seats and cams), in such a
way that the sequence is the same as the one described.
[0048] For the steps for the unloading of the rod from the drilling battery to the loading
device, all the steps described can be understood as specularly valid.
[0049] In a preferred form of embodiment hook 47 is in coupling to the cam with a rotating
element 49A which reduces the frictions and the consumptions of the two elements.
As a matter of fact, for being sufficiently reactive in the movement, the hook needs
a very rigid return spring and this, by exerting a relevant pushing force, creates
a quick wear of the sliding surfaces, which is very relevant even for the quick movements.
By inserting a rolling element this inconvenient is solved.
[0050] According to another characteristics of the present invention, to the revolver-type
loading device 3 is associated a unique anti-rotating plate 6 positioned on arm 35
of the loading device which keeps locked in rotation the sole rod in loading and unloading.
[0051] In this way, the anti-rotating plate can be only one for the whole loading device,
instead of being one for each seat of rod and mounted in proximity of containment
33 and the whole system becomes more simplified.
[0052] Plate 6 comprises preferably a restraining tooth 61 (which can be advantageously
dismantled in order to be adapted for the different types of rod) pivoted on this
plate which constrains against suitable seats 34a obtained on the ending part of rod
34. The rotation of tooth 61 is barred by the action of a spring 62 preferably fixed
to a wall of the plate through a clamp 63 and which favors the contact among tooth
61 and blocking stops 34a obtained on rod 34.
[0053] By using a movable guide instead of a fixed one, it is recovered the stroke necessary
for the drilling and consequently the machines can be resized and cheaper. This is
an enormous advantage mainly for the machines developed for working with the guide
tower near to the horizontal line, wherein a higher length would influence very negatively
the lateral stability and the ground view dimensions which are required.
[0054] The use of mechanical devices in contrast to the elastic means allows to carry out
the loading steps in an automatic way, without having to actuate commands for giving
the single maneuvers.
[0055] The whole step for moving the guide is automatic despite of the systems controlled
by means of actuators (e.g. hydraulic-jacks) positioned between the movable guide
and the carriage which instead would be manually actuated. In this way, even the locking
of the rod does not require the manual intervention of the operator, but the rotating
head itself with the sole rotation is able to unscrew the rods by acting in contrast
with the anti-rotating plates.
[0056] In all the working steps and for all the containing capacity of the loading device,
it is not necessary to call the operator for carrying out manual adaptations necessary
for the centering, exposing him to potential risks in a very dangerous area.
[0057] Eventually, the continuous control of the position in all the movement steps between
upper position S and the one of minimal overall dimensions B, in any direction, allows
for operating in absolute safety without having uncontrollable movements which are
typical of the movable systems which use the simple gravity (usable within a limited
extent in vertical drillings or next to it, but leaving unchanged the safety risks
against possible blocks during the movements and successive fallings of the objects
from different heights and with dynamic impacts on the structures).
1. A drilling machine comprising:
- a supporting structure comprising a guide tower (2) provided with elements for guiding
the sliding (21), upon which a rotating head (23) for sequentially moving drill rods,
to which are given both the movement of rotation and the movements of advancement
in the ground and of successive return, slides,
- a loading device (3) associated to said guide tower, wherein a plurality of drill
rods in battery is positioned,
- a guide device (4) adapted to maintain centred the drill rod present in battery
and/or drawn from the loading device and associated to the rotating head in the desired
direction of drilling,
characterized in that said guide device slides along said guide tower and comprises
- blocking means of the device itself, in a predetermined working position along the
guide tower,
- means for coupling to the rotating head (23) when it moves down during the operation
of drilling with the rod and reaches the guide device in said predetermined position
and
- contrasting means that determine the release of the guide device from the rotating
head and its repositioning in the working position during the ascent of the driving
head itself.
2. A machine according to claim 1, wherein said blocking means comprise at least a mechanic
stop (45) contrasting with first elastic means (46), that push said stops to insert
in at least a retaining seat (24) made on the guide tower in said predetermined position.
3. A machine according to claim 1, wherein said means for coupling comprise at least
a hook (47) that acts in contrast with second elastic means (48), adapted to hook
to at least one projecting element (25) integral with the rotating head.
4. A machine according to claim 3, wherein the contrasting means comprise at least a
cam (26) that acts on at least a shoulder (49) of the hook, thus determining its release
from the projecting element (25).
5. A machine according to claim 3, wherein said guide device (4) slides on the same
guide elements (21) of the rotating head (23).
6. A machine according to claim 1, wherein the loading device (3) is adjustably constrained
to the guide tower by means of a couple of lower arms (35) and upper arms (36) and
is a revolver loading device and comprises a rotating container upon which the rods
are stored, formed by a couple of rotating supports, one upper (31) and one lower
(32), among which are positioned the rods themselves.
7. A machine according to claim 6, also comprising an anti-rotating plate (6) positioned
on the lower arm (35) of the loading device, that blocks in rotation the rod in charging
and discharging on the loading device.
8. A machine according to claim 7, wherein the plate (6) comprises a restraining tooth
(61) that constrains against stops (34A) present on the rod (34), pivoted on said
plate in contrast with elastic means (62) .
8. A machine according to claim 3, wherein the hook (47) is coupled with the cam by
means of a rotating element (49A) .